N-Heterocyclic Carbene Silver(I) Complexes from Xanthines And
N-HETEROCYCLIC CARBENE SILVER(I) COMPLEXES FROM XANTHINES AND
THEIR ANTIMICROBIAL APPLICATIONS
A Dissertation
Presented to
The Graduate Faculty of the University of Akron
In Partial Fulfillment
of the Requirements for the Degree
Doctor of Philosophy
Aysegul Kascatan Nebioglu
May, 2007 N-HETEROCYCLIC CARBENE SILVER(I) COMPLEXES FROM XANTHINES AND
THEIR ANTIMICROBIAL APPLICATIONS
Aysegul Kascatan Nebioglu
Dissertation
Approved: Accepted:
______Advisor Department Chair Dr. Wiley J. Youngs Dr. Kim C. Calvo
______Co-Advisor Dean of the College Dr. Claire A. Tessier Dr. Ronald F. Levant
______Committee Member Dean of the Graduate School Dr. Michael Taschner Dr. George R. Newkome
______Committee Member Date Dr. Christopher J. Ziegler
______Committee Member Dr. Amy Milsted
ii ABSTRACT
This dissertation discusses a newly growing area of the synthesis from xanthine ligands of new silver(I) N- heterocyclic carbene (NHC) complexes and their potential antimicrobial use in cystic fibrosis lung infections. In chapter I, the ligand properties of
NHCs and the synthetic methods for the formation of silver(I) NHC complexes are outlined. An overview of silver antimicrobials and previously synthesized silver(I) NHC complexes from pyridine linked and tripodal imidazolium salts for the topical applications is discussed. Furthermore, a brief summary of cystic fibrosis is given.
Chapter II presents the introductory studies to explore the NHC silver(I) chemistry of caffeine. Formation and characterization of mono and dinuclear bis(NHC) silver(I) complexes from different methylated caffeine salts are given. Chapter III focuses on the formation of an NHC-silver(I) acetate complex from the iodide salt of methylated caffeine. This complex demonstrates a promising antimicrobial activity against numerous resistant respiratory pathogens including members of the Burkholderia cepacia complex which causes a high rate of mortality in patients with cystic fibrosis. Synthesis of NHC silver(I) complexes from theophylline derivatives is given in chapter IV. The antimicrobial activity of these complexes against the same pathogens used in chapter III is presented. In chapter V, the use of a bis(NHC) silver(I) complex from methylated caffeine as a carbene transfer agent is demonstrated and formation of a Rh(I) NHC
iii complex is outlined. Furthermore, the synthesis and characterization of Pt(II) and Pd(II)
NHC complexes of methylated caffeine are presented.
iv DEDICATION
To my beloved husband, Ahmet, for his exceptional support and love.
v ACKNOWLEDGEMENTS
I would like to express my sincere gratitude to my advisor, Professor Wiley J.
Youngs, for his guidance, encouragement and generous support. His kind and understanding approach made me motivated throughout my graduate study. I would also like to extend my thanks to my co-advisor Professor. Claire A. Tessier for her invaluable contributions, knowledge and encouragement.
I would like to thank Professor. Carolyn L. Cannon and her coworkers in
Washington University, Division of Allergy and Pulmonary Medicine for the in vitro and in vivo antimicrobial studies. I extend my thanks to Professor Amy Milsted and
Professor Daniel Ely for letting me use their facilities in Biology department. I also would like to thank Professor Seth D. Crosby for the microarray gene expression analysis. I would also like to extend my thanks to my committee members for their contributions. My appreciation is to National Science Foundation, National Cancer
Institute and National Institute of Allergy and Infectious Diseases for their financial support.
I would also to thank Dr. Jered C. Garrison, Dr. Matthew Panzner, Dr. Semih
Durmus and Doug Medvetz for the characterization of my crystals. I thank to Khadijah
Hindi for the toxicity studies and Dr. Abdulkareem Melaiye for teaching me antimicrobial tests. I would also like to thank all of the other Youngs group members:
vi Dr. Carol Quezada, Samittichai Seeyangnok, Tammy Siciliano, Paul Custer and Brian
Wright for their support and friendship. I appreciate all of the faculty and staff in the
Chemistry department for their assistance.
I would like to thank my parents; ùengül and Adem with all my heart. They
always made me feel their love and support. I was their little girl at all times. I would
also like to express my gratefulness and appreciation to my elder sister Dilek, and her
husband Mehmet Ali for their extraordinary support and encouragement.
Finally, I would like to express my gratitude to my lovely husband Ahmet. You
were always there for me in every step of the way with your love and support. Thank
you being the way you are. You complete me.
vii TABLE OF CONTENTS
Page
LIST OF TABLES ...... xi
LIST OF FIGURES...... xii
LIST OF SCHEMES ...... xiv
LIST OF ABBREVIATIONS AND ACRONYMS……………………………………..xv
CHAPTER
I. INTRODUCTION...... 1
1.1 N-Heterocyclic Carbenes (NHCs) and Silver(I) Complexes ...... 1
1.2 The Use of Silver Compounds as Antimicrobials ...... 6
1.3 Current Literature on the Antimicrobial Properties of Silver NHC Complexes ...... 10
1.4 Cystic Fibrosis...... 19
II. SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF BIS(N-HETEROCYCLIC CARBENE) COMPLEXES OF SILVER(I) FROM CAFFEINE...... 22
2.1 Introduction...... 22
2.2 Results and Discussion ...... 23
2.3 Conclusions...... 31
2.4 Experimental ...... 31
III. SYNTHESIS FROM CAFFEINE OF A MIXED N- HETEROCYCLIC CARBENE-SILVER ACETATE COMPLEX ACTIVE AGAINST RESISTANT RESPIRATORY PATHOGENS...... 37 viii 3.1 Introduction...... 37
3.2 Results and Discussion ...... 39
3.3 Conclusion ...... 53
3.4 Experimental ...... 54
IV. SYNTHESIS OF N- HETEROCYCLIC CARBENE SILVER ACETATE COMPLEXES FROM THEOPHYLLINE DERIVATIVES AND ANTIMICROBIAL ACTIVITY AGAINST RESISTANT RESPIRATORY PATHOGENS...... 63
4.1 Introduction...... 63
4.2 Results and Discussion ...... 66
4.3 Conclusions...... 77
4.4 Experimental ...... 78
V. SYNTHESIS AND CHARACTERIZATION OF N-HETEROCYCLIC CARBENE RHODIUM(I), PLATINUM(II) AND PALLADIUM(II) COMPLEXES FROM CAFFEINE ...... 87
5.1 Introduction...... 87
5.2 Results and Discussion ...... 88
5.3 Conclusions...... 95
5.4 Experimental ...... 96
VI CONCLUSION ...... 100
REFERENCES...... 103
APPENDICES...... 114
APPENDIX A: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C9H13F6N4O2P (CHAPTER II-1b)...... 115
APPENDIX B: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C18H24N8O4Ag, C7H8, PF6 (CHAPTER II-2b)...... 121
ix APPENDIX C: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C18H24Ag2N10O10 (CHAPTER II-2d) ...... 130
APPENDIX D: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C9H13N4O2I, H2O (CHAPTER III-1)...... 137
APPENDIX E: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C20H27AgN8O7, 3CH3OH (CHAPTER III-2)...... 144
APPENDIX F: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C11H15AgN4 O4, 2(H2O) (CHAPER III-4)...... 155
APPENDIX G: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C10H15IN4O3 (CHAPTER IV-1a)...... 164
APPENDIX H: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C11H17IN4O4 (CHAPTER IV-1b)...... 171
APPENDIX I: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C35H35BN4O4, H2O (CHAPTER IV-1c)...... 178
APPENDIX J: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C24H34N8O10Ag2, C2H6O (CHAPTER IV-2a)...... 190
APPENDIX K: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C13H19AgN4O6 (CHAPTER IV-2b)...... 202
APPENDIX L: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C13H15AgN4O6 (CHAPTER IV-2c)...... 209
APPENDIX M: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C19H30N4O3SRh, PF6 (CHAPTER V-1)...... 216
APPENDIX N: SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF C11H18Cl2N4O3PtS (CHAPTER V-2)...... 233
APPENDIX O: INSTITUTIONAL ANIMAL CARE AND USE COMMITTEE (IACUC), ANIMAL STUDIES PROTOCOL APPROVAL…………………………. 240
x LIST OF TABLES
Table Page
1.1 MIC Results of the Silver Compounds ...... 13
2.1 Selective bond lengths and angels for 1b, 2b and 2c...... 29
3.1 Selected bond lengths and angles for 1, 3 and 4...... 44
3.2 Micro-dilution MIC testing of complex 4...... 47
4.1 Selected bond lengths and angles of 2a, 2b and 2c ...... 73
4.2 Micro-dilution MIC testing of complex 2a ……………………………………….. 74
4.3 Micro-dilution MIC testing of complex 2b ………………………………………. .75
4.4 Micro-dilution MIC testing of complex 2c ………………………………………...76
xi LIST OF FIGURES
Figure Page
1.1 General representation of an NHC ...... 1
1.2 The resonance structures depicted on the diamino carbene part of NHC and the aromaticity...... 2
1.3 Bonding of NHCs to metal centers...... 2
1.4 Simplified drawing of silver sulfadiazine ...... 7
1.5 Molecular structure of 2a ...... 12
1.6 Molecular structure of 4...... 14
1.7 TEM images of 50% w 4-50% w Tecophilic® embedded into electrospun polymer mat...... 16
1.8 Kirby Bauer susceptibility test ...... 16
1.9 Transmission electron microscopy (TEM) image of electrospun fibers of 6...... 19
2.1 Methylated caffeine salts and silver(I) complexes ...... 23
2.2 Formation of 2a from 1a confirmed by 13C NMR...... 26
2.3 Molecular structure of the cationic part of 1b...... 28
2.4 Molecular structure of the cationic part of 2b...... 29
2.5 Molecular structure of 2d...... 30
3.1 Methylated caffeine iodide salt and silver complexes ...... 39
3.2 Molecular structure of 1...... 43
xii 3.3 Molecular structure of 3...... 43
3.4 Molecular structure of 4...... 44
3.5 A comparison of the MIC determinations in M-H broth versus LB of the pathogens tested in Table 3.2 ...... 49
3.6 Effects of complex 4 on respiratory pathogens ...... 50
3.7 Transcriptional profiling of murine tracheal epithelial cells (METCs) treated with complex 4 ...... 52
4.1 Theophylline and N-7 substituted derivatives...... 64
4.2 Methylated theophylline salts and silver(I) complexes ...... 65
4.3 Molecular structure of 1a ...... 68
4.4 Molecular structure of 1b...... 68
4.5 Molecular structure of cationic part of 1c ...... 69
4.6 Molecular structure of 2a ...... 71
4.7 Molecular structure of 2b...... 72
4.8 Molecular structure of 2c ...... 72
5.1 Rh(I), Pt(II) and Pd(II) complexes of methylated caffeine...... 88
5.2 13C NMR of complex 1 ...... 90
5.3 Molecular structure of the cationic part of 1 ...... 92
5.4 Molecular structure of 2...... 93
5.5 13C NMR of 3 ...... 95
xiii LIST OF SCHEMES
Scheme Page
1.1 Synthesis of the first Ag(I) NHC complex ...... 3
1.2 Formation of polymeric silver(I) NHC complex using silver(I) acetate...... 4
1.3 The first Ag(I) NHC complexes by Ag2O deprotonation ...... 4
1.4 Synthesis of Ag(I) NHC Complex using Ag2CO3 ...... 5
1.5 The first Pd(II) and Au(I) complexes using carbene transfer Ag(I) NHC complexes.6
1.6 Synthesis of 2a and 2b...... 10
1.7 Synthesis of 3 and 4 ...... 14
1.8 Formation of 5 and 6...... 18
2.2 Synthesis of 2a, 2b, 2c and 2d...... 25
3.1 Synthesis of 1 ...... 40
3.2 Formation of 3 and 4...... 41
3.3 The direct synthesis of 4 ...... 42
4.1 Synthesis of 1a, 1b and 1c ...... 66
4.2 Synthesis of 2a, 2b and 2c ...... 69
5.1 Synthesis of 1 by carbene transfer from B...... 89
5.2 Synthesis of 2 ...... 91
5.3 Synthesis of 3 ...... 93
xiv LIST OF ABBREVIATIONS AND ACCRONYMS
Å Angstrom MBC Minimum bactericidal concentration
Anal. Analysis MIC minimum inhibitory concentration
ȝg Microgram ȝL Microliter
ı bond referring to bonding p bond referring to bonding between sigma orbitals between pi orbitals
CFTR cystic fibrosis transmembrane CF cystic fibrosis regulator
Bcc Burkholderia cepacia complex LD50 lethal dosage concentration required to kill half population of animal
QAC quaternary ammonium compounds ALD approximate lethal dosage
DMF dimethyl formamide Wr2 weighted residual based on
ESI- electrospray ionization mass Fc calculated structure factor MS spectrometry
M-H Mueller-Hinton Fo observed structure factor
SEM Scanning electron microscopy TEM transmission electron microscopy
MTECs murine tracheal epithelial cells MEEBO mouse exonic evidence based oligonucleotide
xv NCCLS National Committee for Clinical ATCC American type culture Laboratory Standards collection
LB Luria broth S goodness of fit
CCD charge coupled device l crystallographic index
M Concentration in moles per dm3 w/v weight per volume
% wt weight percent h Hour
NHC N-heterocyclic carbine Ȝ wave length
U temperature factor K crystallographic index nJ nuclear spin-spin coupling I integrated intensity constant through bonds h crystallographic index Hz Hertz
Į crystallographic unit-cell angle a crystallographic unit cell between axes b and c axis a
ȕ crystallographic unit-cell angle b crystallographic unit cell between axes a and c axis b
ī crystallographic unit-cell angle c crystallographic unit cell between axes a and b axis c
ȍ angle (diffractometry) Ȍ angle (diffractometry)
ĭ angle (diffractometry) Ȥ angle (diffractometry)
0C degree celsius
xvi CHAPTER I
INTRODUCTION
1.1 N-Heterocyclic Carbenes (NHCs) and Silver(I) Complexes
N-heterocyclic carbenes (NHCs) are cyclic carbenes (Figure 1.1) that are usually derived from the deprotonation of imidazolium salts. NHC chemistry was first investigated by Wanzlick1,2,3 in the early 1960s leading to the synthesis of the first NHC transition metal complexes of chromium and mercury by Öfele4 and Wanzlick5 in 1968.
The following decades saw limited activity in this area, the most notable by Lappert and co-workers who synthesized several NHC metal complexes from electron- rich olefins.6,7,8 The isolation of the first stable NHC, 1,3-diadmantylimidazol-2-ylidene, by
Arduengo in 19919 was a breakthrough and led to significant interest in this field of chemistry. The coordination chemistry of NHC metal complexes continues to be actively studied, particularly for catalytic applications.10
R R N N
Figure 1.1 General representation of an NHC
1 NHCs are strong nucleophiles and bind to both main group and transition metals often with greater stability than phosphines.11 The carbene carbon atom of NHCs is
stabilized by the pp - pp electron donation of the two adjacent nitrogen atoms accounting
for a stabilization energy of approximately 70 kcal/mol. For unsaturated systems
aromaticity can contribute an additional 25 kcal/mol of stabilization (Figure 1.2).11,12 The
nitrogen atoms also stabilize the lone pair electrons of the carbene inductively.11,12
Although NHCs are viewed mainly as ı-donors, recent theoretical and structural studies13,14,15,16,17 suggest the existence of some ɉ-backbonding for certain metal centers
(Figure 1.3).18
N : N N : N N : : :
N : N : N N N
Figure 1.2 The resonance structures depicted on the diamino carbene part of NHC and the aromaticity. (Taken from reference 12)
N
M C
N
Figure 1.3 Bonding of NHCs to metal centers. (Taken from reference 18)
2 The first silver NHC complex was synthesized using a free carbene (Scheme
1.1).19 However, this method has been applied to the synthesis of only a limited number of silver NHC complexes20-22 due to the difficulty of generating most free carbenes, which have sensitivities to air, moisture and heat.18,23
KH N or N N N AgO SCF + - + KOtBu 3 3 Ag CF3SO3 N N N N
Scheme 1.1 Synthesis of the first Ag(I) NHC complex
The in situ deprotonation of imidazolium salts with basic silver precursors is the most commonly used method to synthesize silver NHC complexes. The most commonly utilized base is silver(I) oxide; other bases such as silver(I) acetate and silver(I) carbonate are also used. The first example of this method was the reaction of a triazolium salt and silver acetate by Bertrand and co- workers (Scheme 1.2).24,25 The reaction of dicationic triazolium salt with two equivalents of silver(I) acetate resulted in the formation of the first polymeric NHC silver(I) complex.
3 + 2+ R R2 1
N N AgOAc 2CF SO - - 3 3 Ag CF3SO3
N N N N R R n R1 R1 1 1
R1= CH3
CH3 R2= HC CH3
Scheme 1.2 Formation of polymeric silver(I) NHC complex using silver(I) acetate
The use of silver oxide to give silver complexes of 1, 3- diethylbenzimidazole- 2- ylidine was pioneered by Lin and co- workers (Scheme 1.3).26 More recently, Danapolous and
co-workers reported the use of silver carbonate to deprotonate imidazolium salts to give
silver NHC complexes (Scheme 1.4).27
N N N _ Ag2O + X Ag X = Br- N N Br N Ag
Ag2O Br - X = PF6
N N + _ Ag PF6 N N
Scheme 1.3 The first Ag(I) NHC complexes by Ag2O deprotonation
4 Br N R Ag N N Br N Ag CO 2 3 Ag N Br H N N R N N
R i R = 2,6-Pr2 C6H3
Scheme 1.4 Synthesis of Ag(I) NHC Complex using Ag2CO3
The use of silver oxide has made the synthesis of silver NHC complexes much easier.28,29 The reactions can be performed at ambient conditions, in a variety of solvents including water with little work up.30,31,32 The formation of silver complexes in water suggests that the deprotonation of the imidazolium salt and coordination to the metal center is a concerted process because free NHCs are water sensitive.23
Silver NHC complexes show various structures in the solid state. The amounts and nature of silver reagents and imidazolium salts used in the synthesis, counter anions, solvent and temperature can all affect the structure. A more detailed discussion on the synthesis, characterization and structural diversity of the silver NHC complexes can be found in reviews by Lin and Vasam and Garrison and Youngs.18,23
The lack of 107/109Ag-13Ccouplings in various silver NHC complexes suggests that the silver-carbene bond is labile, and has lead to their use as carbene transfer reagents.
This method was first used by Lin and coworkers to synthesize palladium and gold
5 complexes,26 and several transition metal complexes have been synthesized utilizing this
method (Scheme 1.5).34,35,36
Et Et Et Et Cl N N N N Pd(MeCN) Cl Ag 2 2 Pd N Br N N N Ag Cl Br Et Et Et Et
Et Et Et Et
N N N N Au(SMe2)Cl Ag PF6 Au PF6 N N N N
Et Et Et Et
Scheme 1.5 The first Pd(II) and Au(I) complexes using carbene transfer Ag(I) NHC complexes
1.2 The Use of Silver Compounds as Antimicrobials
Background on Silver Antimicrobials
The use of silver as an antimicrobial can be traced to ancient times. Early
civilizations used silver metal to purify and store drinking water.37 The antimicrobial properties of silver nitrate were well known long before the 1800s, and it was recognized as an antiseptic in wound care for more than 200 years.38 In the late nineteenth century, it was reported that at very low concentrations silver compounds killed certain microorganisms and the term oligodynamic, active with few ions, was used for the first time to explain this property.37,39 In 1881, Créde began the use of 2 % silver nitrate solution to prevent eye infections in newborns.40 Colloidal silver solutions were introduced in the early twentieth century to avoid the irritation associated with silver
6 nitrate and remained popular until the 1940s.41,42 Silver compounds then lost favor
following the discovery of penicillin and other new antibiotics.38 The use of 0.5 % silver
nitrate solution for the treatment of burn wounds by Moyer rekindled an interest in the
area.43 However, the true revival of the use of silver antibiotics came with the discovery
of silver sulfadiazine by Fox in 1968.44 Silver sulfadiazine (Figure 1.4) is used for the
treatment of burn wounds, and was designed to combine the antibiotic sulfonamide,
sulfadizine, with silver in order to obtain a wide spectrum antibiotic. It is a water
insoluble complex and is polymeric in the solid state.45 Silver sulfadiazine has been
shown to be effective against a number of gram-positive and gram-negative bacteria, and
is marketed as a water soluble cream, Silvadeneâ cream 1%. It remains one of the most
widely used antimicrobials for infections associated with burns.
Ag O N NH2 S N O N
Figure 1.4 Simplified drawing of silver sulfadiazine. (Taken from reference 50)
Silver has also been introduced into wound dressings in the form of organic and
inorganic silver compounds and as silver metal, usually in the nanocrystalline form.46
The aim of the silver containing dressings is not only the sustained release of silver to the
wound site creating a barrier for infection, but also ease of use, management of wound
exudates and provision of moisture required for optimal wound healing.38,46a Silver has
7 been impregnated in several different kinds of dressing materials including nylon fabrics, meshes, biodegradable collogens, low adherent materials, carbon fibers, and hydrofiber alginates. 38,46a Such silver containing dressings have been used in the treatment of acute
and chronic wounds, leg ulcers and several degrees of burn wounds.46
Mechanism of Action and Toxicity of Silver
Silver is effective against a broad range of gram negative and gram positive
bacteria, fungi and yeast. The pure metal is inactive; however, in the presence of
moisture, silver readily ionizes to give silver cations, which show antimicrobial
activity.47,34 As early as the 1800s, Von Nägeli reported that 10-5- 10-8 M of silver cations derived from metallic silver were effective to stop the growth of A. niger spores.39
The activity of silver cations depends on their bioavailability.48 For example,
recent studies have shown that in the presence of high concentrations of chloride anions,
– silver becomes more bioavailable forming soluble anionic AgCl2 compounds rather than precipitating as AgCl. Both sensitive and resistant bacteria show increased sensitivity to silver in the presence of chloride anions which is likely due to increased access of the
Ag+ ion to the cell membrane.49 Delivery methods, solubility and ionization of the silver sources can also affect the bioavailability. 48,50
The mechanism of action of silver cations is not yet completely understood.
Silver cations bind to bacteria cell surfaces, and interact with enzymes and proteins important for cell wall synthesis. Silver can also affect cell respiration, transport and metabolism, as well as DNA, RNA, and subcellular organelle structure.46,50 Evidence for the action of the silver cations on the cell wall of the yeast C. albicans has been
8 reported.51 It was found that silver cations bind to the cysteine residues of the essential enzyme phosphomannose isomerase used in the synthesis of the yeast cell wall resulting in loss of cell wall integrity. In addition to its antimicrobial activity, silver helps the healing process by blocking matrix metalloproteinases, which delay healing of chronic wounds.52,53
Silver antimicrobials have been known to cause a rarely seen cosmetic side effect
known as argyria. Argyria is a gray to blue discoloration of the skin due to the deposition
of silver sulfide and silver(0).54,55 It is an irreversible side effect resulting from chronic exposure to silver containing products. Silver taken into systematic circulation is excreted in the urine. The levels of silver in urine of burn patients treated with topical silver antimicrobials has been shown to increase.56,57 Some cytotoxicity studies have shown that silver salts affect the growth of keratin producing epidermal cells,58 bone
marrow,59 connective tissue cells,60 hepatocytes61 and lymphocytes62 by inhibiting
cellular respiration with the loss of ATP.60 However, other studies have reported no
observed cytotoxicity of silver.63-65 Therefore, the present literature is inconclusive
regarding the potential toxicitites of silver antimicrobials.
Bacterial resistance to silver has been rarely reported. Silver sulfadiazine
resistant strains of P. aeruginosa have arisen in burn units; the mechanism of resistance is currently unknown.66-68 In contrast, the mechanism of resistance of a Salmonella strain that resulted in numerous patient deaths and the closing of a burn ward69 has been well studied. This strain carries a plasmid, pMG101 that encodes a peri-plasmic silver binding protein (SilE) and two parallel efflux pumps (SilCBA and SilP).48,70 Subsequently,
9 plasmid-mediated resistance to silver has been identified in several other strains of bacteria.71,72,73
1.3 Current Literature on the Antimicrobial Properties of Silver NHC Complexes
Pyridine Linked Pincer NHC- Silver Complexes
Widely used topical antimicrobials such as silver sulfadiazine and silver nitrate
have been observed to kill bacteria quickly, but loose their effect in a short time causing
the wound site to be reinfected. Moreover, discoloration of the skin and development of
resistance of some organisms to sulfonamides limit the use of conventional silver
antibiotics.66- 68 The slow release of silver at the wound sites is essential for faster healing
and the prevention of infections.53,74 The strong binding ability of NHCs to silver can
result in more stable complexes that can slowly release silver ions, thus retaining the
antimicrobial effect over a longer period of time. The NHC silver(I) complexes 2a and
2b from pincer ligands 1a and 1b that are substituted by hydroxyethyl and hydroxypropyl groups were synthesized. The antimicrobial properties against clinically important microorganisms was investigated (Scheme 1.6).75
N 2X N N OH N N N N N N OH Ag O H H 2 * Ag Ag * N N CH3OH, RT N N N N
CH2 CH2 CH2 CH2 CH2 CH2 m m m m m m OH HO OH HO OH HO n 1a X = I, m = 2 2a, 2b 1b X = Br, m = 3
Scheme 1.6 Synthesis of 2a and 2b 10 The pyridine linked pincer ligands were synthesized from the reaction of 2,6- bis(imidazolemethyl)pyridine with iodoethanol and 3-bromopropanol respectively. The reaction of 1a and 1b with silver oxide in aqeous methanol gave the corresponding silver
NHC complexes, 2a and 2b. Complex 2a was observed to be a one dimensional polymer
in the solid state (Figure 1.5) with the carbene-silver-carbene bond angle between the
repeating units of 174.7(4)o and the silver carbene bond lengths of 2.108(11) and
2.060(13) Å. However, mass spectrometry suggested that 2a exists as a monomer in the gas phase.
Complexes 2a and 2b were tested against the clinically relevant bacteria, E. coli,
S. aureus and P. aeruginosa to determine the minimum inhibitory concentration (MIC).
MIC denotes the lowest concentration that inhibits the visible growth of the microorganism after overnight incubation76 and is accomplished through a standard serial dilution method. Upon dissolving the complexes in the culture medium (Luria-Bertani broth), both NHC silver complexes and silver nitrate precipitate a small amount of silver chloride. The precipitate was filtered and a dilution series of the complexes were prepared. Freshly grown organisms at a constant volume were added to the dilution series on a daily basis. As shown in Table 1.1, 2a and 2b showed better bacteriostatic effect (lower MIC value) than silver nitrate at about 2.7 times lower initial silver ion concentration. This result showed that although the theoretical amounts of the silver cations released from 2a and 2b were lower than silver nitrate, more silver cations were in the solution from 2a and 2b. Most of the silver cations from silver nitrate were precipitated as silver chloride and lost activity. The 0.1% chloride anion concentration in the culture medium is close to physiological concentrations of chloride (0.15 M sodium
11 chloride). Under these conditions, 2a and 2b were more stable than silver nitrate.
Moreover, when the solutions demonstrating the lowest MIC value were inoculated onto
agar plates, the growth of organisms treated with 2a and 2b was delayed for a longer time
than was the growth of organisms treated with silver nitrate. The observed results can be
explained by the slow decomposition of the silver NHC complexes in the aqueous culture
medium to imidazolim cation and biologically active silver species. Compounds 2a and
2b were observed to decompose over a period of weeks in deionized water.
Figure 1.5 Molecular structure of 2a. (Taken from reference 75)
12 Test Ag E. coli P. aeruginosa S. aureus compounds mg/mL day1 day 2 day1 day 2 day1 day 2 2a 1186 ------1DF - + - - - + 2DF - + - + + 3DF + + + 4DF + + + 2b 1125 ------1DF - + - + - + 2DF - + - + - 3DF + + + 4DF + + +
AgNO3 3176 - + - + + 1DF + + + 2DF + + + 3DF + + + 4DF + + +
Table 1.1 MIC Results of the Silver Compounds (silver chloride removed) DF = Dilution Factor (1 mL). Growth = + , no growth = – (Taken from reference 75)
Another pyridine linked pincer NHC precursor was obtained by the reaction of
2,6- bis(imidazolemethyl) pyridine with 1,3- dichloroacetone. The expected imidazolium salt was obtained as a gem-diol 3 instead of carbonyl linked cyclophane, which can be explained by an acid catalyzed process. The reaction of 3 with silver oxide in aqueous methanol gave complex 4 (scheme 1.7).77 The single crystals of 4 have silver carbene bond lengths ranging between 2.072(5) to 2.085(5) Å. There is a weak interaction between the silver centers at a distance of 3.375(10) Å, which is within the van der Waals distance (3.44 Å) for two silver atoms (Figure 1.6).
13 N N N N N CO(CH2Cl)2 Ag O 2OH N N N 2 2Cl N Ag N N CH3CN N Ag N N CH3OH N N N N N N
HO OH HO OH HO OH 3 4
Scheme 1.7 Synthesis of 3 and 4
Figure 1.6 Molecular structure of 4. (Taken from reference 77)
Complex 4 was encapsulated into an electrospun polymer mat and the antimicrobial activity of this mat was investigated against the bacteria E.coli, P. aeruginosa, S. aeureus and the fungi C. albicans, A. niger and S. cerevisiae. Electrospun polymer mats have found wide range of biomedical applications including wound dressings. The polymer mats are obtained by using electrically charged polymer solution or melt which creates fibers upon elongation. With the electrospinning process, nanofiber polymer composites can be easily produced.78 Complex 4 is slightly soluble in water, but
14 very soluble in ethanol and stable for more than 24 hours. Complex 4 was encapsulated into a medical grade polymer Tecophilic® (polyurethane), which can be electrospun from ethanol. Tecophilic® can absorb water up to 150% of its dry weight. Absorption of water by the polymer mat provides the required moisture for the slow release of the silver active species from the encapsulated complex and also provides essential moisture for wound healing.79 The fiber mat encapsulated with 4 was characterized with transmission electron microscopy (TEM). In dry conditions, a uniform mixing of 4 and the polymer fibers was observed. However, when the fiber mat was exposed to humidity, slow decomposition of 4 resulted in the deposition of nano sized silver particles in the fiber mats (Figure 1.7).
A susceptibility test to determine the bactericidal activity of encapsulated complex 4 was performed by using a modified Kirby Bauer method. Pure Tecophilic® fiber mat was used as the control agent. Fiber mats with a composition of 25% 4 by weight (25% w) and 75% Tecophilic® by weight (75% w) and 75% w 4 and 25% w
Tecophilic® were put on to LB agar plates containing a lawn of organisms. The plates were incubated at 35 oC overnight for the bacteria and at 25 oC for 48 h for fungi. Zones of inhibition around the fiber mats containing different silver complexes were observed
(Figure 1.8). However, this test was not a quantitative tool to evaluate the antimicrobial activity, because the diameters of the zones of inhibition were found to be in non-linear relationship to the amount of the silver complex encapsulated (25% w 4-75% w
Tecophilic®, 2.00 mm versus 75% w 4-25% w Tecophilic®, 4.00 mm).
15 Figure 1.7 TEM images of 50% w 4-50% w Tecophilic® embedded into electrospun polymer mat (a) before exposure to a high moisture environment (b) after exposure to a high moisture environment for 30 min (c) after exposure to a high moisture environment for 65 h. (Taken from reference 77)
Figure 1.8 Kirby Bauer susceptibility test a. 25% w 4-75% w Tecophilic® b. pure Tecophilic® c. 75% w 4-25% w Tecophilic® . (Taken from reference 77)
16 Complex 4 is sparingly soluble and decomposes quickly in water. Silver nitrate showed better antimicrobial activity (MIC of 433 ȝg/mL) than the unencapsulated complex (838 ȝg/mL) after a 2 day-incubation period. However when 4 was encapsulated, the polymer mat containing 25% w 4–75% w Tecophilic® having the lowest initial silver concentration of 140 ȝg/mL ([Ag+] = 140 ȝg/mL) showed a complete killing of bacteria for days with the addition of a constant volume of freshly grown organisms on a daily basis. Moreover, when the killing rate of the encapsulated complex was compared with the conventionally used 0.5% silver nitrate and 1% silver sulfadiazine cream (SSD) (in the culture environment on a constant amount of bacteria with respect to time) both polymer mats 75 % w 4- 25 % w Tecophilic® ([Ag+] = 424 ȝg/mL) and 25% w 4-75% w Tecophilic® ([Ag+] = 140 ȝg/mL) showed a better killing rate than SSD
([Ag+] = 3020 ȝg/mL). The fiber mat having about 8-fold lower silver concentration
([Ag+] = 424 ȝg/mL) than the silver nitrate ([Ag+] = 3176 ȝg/mL) showed almost the same kill rate.
Encapsulation of the silver NHC complex increased the antimicrobial activity by enabling a slower release of active silver species. The fibers of the polymeric mat also provided a greater surface area for the active silver species to be released and increased the efficiency of the silver. The deposition of the active silver species in the fiber mat helps the culture medium to retain its original color, unlike silver nitrate which changes the LB broth to dark brown. The active species released from the spun mat in the culture environment may include silver cations, nano sized silver particles, clusters of silver cations, and anionic silver chloride complexes.
17 Silver Tripodal N-Heterocyclic Carbene Complexes
A trinuclear silver(I) NHC complex 6 was synthesized from tris-imidazolium salt
of pentaerythritol 5 and silver(I) oxide in methanol (Scheme 1.8).50 Complex 6 showed a
13 doublet carbene peak centered at 182 ppm with a coupling constant JAg- Cs = 196 Hz
109 13 80 J 109 13 which is close to usually observed Ag- C coupling ( Ag- C = 204-220 Hz). Single
crystals of 6 could not be obtained. Therefore the exact nature of the anion of 6 was not
determined. Based on elemental analysis, mass spectrometry and x-ray energy dispersive
spectroscopy (XEDS), the presence of bromide was confirmed.
N R OH N R 3X 3Br N Ag N N N N R N Ag R HO Ag2O R N R CH OH N N N 3 R N N N N X = Br, OH, AgBr , Ag Xn Ag 2 n m R R= nC4H9 N OH
N R 5 6
Scheme 1.8 Formation of 5 and 6
Complex 6 was encapsulated in Techophilic® polymer and antimicrobial activity
of the polymer mat was tested against E. coli, P. aeruginosa, S. aureus, C. albicans, A.
niger, and S. cerevisiae on a lawn of organism in an agar plate. Complex 6 showed both
bactericidal and fungicidal activity creating a clear zone around the polymer mat.
18 The electrospun fibers of 6 showed an aggregation of silver particles in the range
of 50-100 nm in diameter when exposed to water (Figure 1.9). Formation of larger sized
silver particles than the ones from complex 4 (<20 nm) on the electrospun fiber surface
was thought to be due to the presence of bromide in the complex 6. Based on the 1H
NMR spectrum of 6 encapsulated in Techophilic®, most of the ligand 5 was observed to be kept in the polymer matrix of the mat while the complex slowly decomposes in water. The silver particles accumulate on the surface of the fibers.
A B
Figure 1.9 Transmission electron microscopy (TEM) image of electrospun fibers of 6 A. Uniform mixing of 6 and Techophilic. B. Silver particles accumulate on the fiber surface in the presence of water. (Taken from reference 50)
1.4 Cystic Fibrosis
Cystic fibrosis (CF) is the most common life-threatening, autosomal recessive disease seen mostly in Caucasian populations.81 It affects 30,000 people in the United States and 70,000 people worldwide.82 It is caused by the mutations in cystic fibrosis transmembrane conductance regulator (CFTR) gene found on chromosome 7.
Since the discovery of CFTR gene in 1989, more than 1,200 mutations of this gene have
19 been reported. This gene encodes a membrane protein, CFTR, expressed in the epithelial cells. CFTR protein is an integral membrane protein composed of 1480 amino acids. It functions as a chloride selective ion channel and is also known to have a regulatory influence on the other ion channels.83 Its activity is regulated by cyclic adenosine
monophosphate (c-AMP) and ATP hydrolysis is needed for channel gating. It is found in
several tissues producing mucus, sweat, saliva, tears, and digestive enzymes establishing
fluid consistency of these secretions.84
Although CF is a multi-organ disease, the most severe effects are seen in the
lungs.85 Most of the morbidity and the mortality is caused by the chronic infections and inflammation seen in the respiratory airways. The mechanism of how the defective
CFTR protein causes progressive lung disorders is not understood completely. Several possible theories have been proposed.81,84,86,87,88 According to a major theory81,84,87 malfunction of the CFTR protein decreases chloride release into the mucus layer on the airway surface. This causes excessive absorption of sodium and water from the mucus to the airway lining epithelial cells. A viscous mucus forms and traps bacteria.
The average survival age for CF patients is mid-30s and more than 90% of the patients die from respiratory failure.75 Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa) and Haemophilus influenzee (H. influenzee) are the most common pathogens causing chronic lung infections.89 The less common pathogens are a group of bacteria known as Burkholderia cepacia complex (Bcc) organisms.90 P. aeruginosa, S. aureus and Bcc organisms cause most of the morbidity and mortality.91
These bacteria form a protective matrix known as a biofilm and show enhanced resistance to antibiotics.83 Especially, Bcc organisms have an inherent antibiotic
20 resistance and cause more morbidity and mortality than P. aeruginosa. CF patients infected with Bcc organisms can have “cepacia syndrome” causing progressive loss of lung function and death in a short time. One of the recently emerging Bcc organisms, B. cepacia genomovar VI, known as B. dolosa, shows the most antibiotic resistance among the Bcc organisms causing a high rate of lung deterioration and death in
CF patients.90 Antibiotics play a key role in the improved survival for the CF patients.
The focus in this area is on the use of nebulized antibiotics.92,93,94
21 CHAPTER II
SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF
BIS(N-HETEROCYCLIC CARBENE) COMPLEXES OF SILVER(I) FROM
CAFFEINE
2.1 Introduction
Caffeine, 1,3,7-trimethylxanthine, is one of the xanthine derivatives that are generally used in medicines as diuretics, central nervous system stimulants and inhibitors of cyclic adenosine monophosphate (c-AMP) phosphodiesterase.95 It is the most popular methylxanthine due to its commercial availability, low cost, and low toxicity. The presence of the methylimidazole moiety in the structure of caffeine makes it a valuable candidate for the synthesis of an N-heterocyclic carbene. The first step is to obtain an imidazolium cation, such as 1,3,7,9-tetramethylxanthinium or methylated caffeine, from caffeine. Previously, formation of methylated caffeine with hydroxide,96 methylsulfate,95,97 tosylate,97 and iodide98 anions were reported. The physiological action of 1,3,7,9-tetramethylxanthinium hydroxide in frogs was explored.96 After introduction of the following work, another NHC precursor of methylated caffeine with tetraflouroborate anion was also reported by Herrmann and coworkers.99 Several silver(I) complexes of xanthines including caffeine in which xanthines are linked to silver(I)
22 via N-9 atom were synthesized.100 However, to the best of our knowledge formation of a silver(I) NHC complex from caffeine has not been reported. We have reported herein the synthesis and characterization of two bis(NHC) silver(I) complexes 2a, 2b from
methylated caffeine 1a, 1b and a dinuclear silver(I) bis(NHC) complex, 2d with the bridging nitrate units from nitrate salt of the methylated caffeine 1d (Figure 2.1).31
+ O CH3 O CH3 H3C O CH3 CH3 CH3 N N N N N N X Ag X N N O N NH O N N O
CH3 CH3 CH3 CH3 H3C CH3
1a X=CH3SO4 2a X= CH3SO4
1b X=PF6 2b X=PF6 1c X= I
1d X= NO3
O O O O CH3 H3C CH3 N CH3 N N N O N Ag Ag O N N O N N O CH3 N H3C CH3 O O CH3
2d Figure 2.1 Methylated caffeine salts and silver(I) complexes
2.2 Results and Discussion
Methylated caffeine, 1,3,7,9-tetramethylxanthinium 1a, was synthesized by the reaction of caffeine with dimethyl sulfate in a 1:2 molar ratio95 and converted to 1b by
23 1 13 ion exchange with NH4PF6 (Scheme 2.1). The H and C NMR spectra of 1a and 1b are similar and consistent with their molecular structures. In the 1H NMR spectra of 1a and
1b, the imidazolium protons appear at 8.93 and 9.25 ppm, respectively. This is consistent with the general C-H acidic proton shift of imidazolium salts (į = 8-10).11 The 13C NMR shift of the N-C-N sp2 carbons, that later become the carbene centers, appear at 139.8 and
139.4 ppm for 1a and 1b, respectively.
CH O CH3 O CH3 O 3 CH3 CH3 CH3 N N N N (CH3)2SO4 N NH4PF6 N CH3SO4 PF6 N N O N O N C6H5NO2 O N H2O N
CH CH3 CH3 CH3 3 CH3 Caffeine 1a 1b
CH3I/DMF
O CH3 O CH3 CH 3 CH3 N N N N I AgNO3 NO3 O N N CH3OH2 O N N
CH3 CH CH3 CH3 3
1c 1d
Scheme 2.1 Synthesis of 1a, 1b, 1c and 1d
The water soluble ligand 1a was reacted with Ag2O in water to form 2a.
Complex 2a is stable in water and in the dark for five days. Similarly, ligand 1b readily
o reacted with Ag2O in DMSO at 60 C to yield the silver NHC complex 2b in high yield
(Scheme 2.2). Complex 2b is stable in air and light up to its melting point and is only soluble in DMSO. It is stable in wet DMSO for months in the light. The formation of 2a
24 and 2b can be monitored by changes in the 1H NMR and 13C NMR spectra (Figure 2.2).
The disappearance of the resonance for the imidazolium protons of 1a and 1b and the
appearance of the resonance for the carbene carbon atoms at 187.1 and 186.6 ppm
respectively, shows the formation of expected NHC silver carbene complexes. The lack
of C-107Ag and C-109Ag couplings suggests fluxional behavior on the 13C NMR timescale as observed with many silver(I) complexes.101 It has been reported that silver-carbene complexes without Ag-carbene couplings are useful as carbene transfer reagents due to their dynamic behavior in solution.26,102 + CH O CH3 O 3 H3C O CH H C CH3 3 3 N N N 2 N Ag2O/H2O N N X Ag CH3SO4 N O N N N N O N X= CH3SO4 O CH CH CH3 3 H3C CH3 CH3 3 2a
Ag2O/DMSO X=PF6
+
O CH3 H3C O CH3 H3C N N N N Ag PF6 O N N N N O CH CH3 3 H3C CH3 2b
O CH3 O CH O O O CH 3 H3C CH3 3 N CH3 N N N N N 2 N Ag2O/CH3CN O X Ag Ag N O O N N X= NO O N N N O 3 CH 3 N H3C CH CH3 O O CH3 3 CH3
2d Scheme 2.2 Synthesis of 2a, 2b, 2c and 2d
25 Figure 2.2 Formation of 2a from 1a confirmed by 13C NMR
26 Methylation of caffeine was also performed with methyl iodide in boiling DMF in order to obtain an NHC precursor, 1c with a biologically relevant anion. The procedure for the synthesis of 1c, its reaction with silver(I) precursors and antimicrobial applications are given in detail in the next chapter. Compound 1c was dissolved in acetonitrile and one equivalent of AgNO3 was added (Scheme 2.1). The resulting silver(I) iodide precipitate was filtered off and solvent removed in vacuo to obtain 1d.
1H NMR and 13C NMR spectra of 1d are very similar to spectra of 1a and 1b. The imidazolium proton resonance for 1d appears at 9.33 ppm. ESI-MS analysis shows the
+ [M-NO3] cation by a m/z peak at 209.1. Elemental analysis of crystals of 1d obtained from the slow evaporation of concentrated methanol solution confirms the presence of nitrate anion. The reaction of 1d with silver(I) oxide in 2:1 ratio in acetonitrile did not result in formation of a silver(I) complex even by heating. Complex 2d was formed by the reaction of 1d with excess silver(I) oxide (1:1 ratio) in acetonitrile at room temperature (Scheme 2.2). 2d is a light stable solid and was observed to be stable in water for 36 days. 1H NMR and 13C NMR spectra of 2d are also very similar to spectra of 2a and 2b. Carbene carbon appearing at 187.1 ppm and ESI-MS spectrum show the
+ + existence of the [Ag(NHC)2] cation as well as [Ag(NHC)] . The molecular structure of complex 2d was revealed by X-ray diffraction studies.
Single crystals of 1b were obtained by the anion exchange of 1a in water. The asymmetric unit of this molecule consists of one methylated caffeine cation and one hexafluorophosphate counteranion. The ligand 1b has an N1-C1-N2 angle of 110.9(3)o.
The N1-C1 and N2-C1 bond lengths are 1.341(4) Å and 1.311(4) Å, respectively (Figure
2.3 and Table 2.1).
27 Figure 2.3 Molecular structure of the cationic part of 1b. Thermal ellipsoids are drawn at 50% probability.
Crystals of 2b suitable for single crystal x-ray diffraction studies were grown
from a concentrated solution of DMSO and toluene (Figure 2.4). The following
explanation about the crystal structure of 2b was written by Matthew Panzner. The
asymmetric unit contains one quarter of both the methylated caffeine silver complex and
the disordered hexafluorophosphate anion together with toluene as a noncoordinating
solvent molecule located on the (x, 0, z) mirror plane. The silver and phosphorus atoms
are on special positions (0, 0, z) and (0, 1/2, z), respectively, with both having mm2
symmetry. Complex 2b is a planar structure, crystallographically imposed, with a silver
carbene bond distance of 2.068(4) Å. The C1-Ag-C1A bond angle is 171.4(3)o that slightly deviates from the linear geometry expected for the complex (Table 2.1).
28 Figure 2.4 Molecular structure of the cationic part of 2b. Thermal ellipsoids are drawn at 50% probability. Hydrogen atoms have been omitted for clarity.
Bond Lenghts and Angles 1b 2b 2c N1-C1 1.341(4) Å 1.372(6) Å 1.354(4) Å N2-C1 1.311(4) Å 1.344(6) Å 1.381(5) Å N1-C1-N2 110.9(3)o 105.6(3)o 105.3(3) o C1-Ag - 2.068(4) Å 2.087(4) Å Ag1-O3 - - 2.328(2) Å Ag1A-O3 - - 2.374(2) Å C1-Ag-C1A - 171.4(3)o - C1-Ag1-O3 - - 149.45(12)o C1-Ag1-O3A - - 142.86(11)o O3-Ag1-O3A - - 64.98(10)o
Table 2.1 Selective bond lengths and angles for 1b, 2b and 2c
29 Figure 2.5 Molecular structure of 2d. Thermal ellipsoids are drawn at 50% probability.
Single crystals of 2d were grown from the concentrated 1:4 methanol/acetonitrile
solution (Figure 2.5). The two silver atoms are in distorted trigonal planar geometry with
the bond angles of 149.45(12)o, 142.86(11)o and 64.98(10)o. Silver carbene bond length is
2.087(4) Å. Nitrate molecules act bridging ligands between two silver atoms. The silver- oxygen bond lengths of 2.328(2) Å and 2.374(2) Å are consistent with those reported for silver(I) nitrate complexes in the literature (Table 2.1).103,104,105 The distance between two silver atoms is too long to have a non-bonding interaction (Ag…Ag distance of ~3.9 Å vs. van der Waals radii 3.44 Å106). Although several silver(I) NHC complexes with bridging halides have been characterized, to the best of our knowledge silver(I) NHC complexes with bridging nitrate anions are rare.18,107
30 2.3 Conclusions
The stability in aerobic conditions and relatively easy synthesis of methylated caffeine make it a very useful N-heterocyclic carbene precursor. We have synthesized bis(NHC) silver(I) complexes 2a, 2b and a dinuclear silver(I) bis(NHC) complex, 2d from different salts of methylated caffeine. These are the first examples of silver(I) NHC complexes derived from caffeine. The formation 2a in water suggests that the deprotonation of the imidazolium salt and coordination to the metal center is a concerted process. All the synthesized complexes show fluxional behavior in solution and can be used as carbene transfer reagents for the synthesis of other transition metal complexes.
2.4 Experimental
General Considerations
All manipulations were carried out in air. The compounds dimethyl sulfate and
Ag2O were purchased from Aldrich and used without further purification. Caffeine was purchased from Acros and used without further purification. 1H and 13C NMR data were recorded on a Gemini 300 MHz instrument and referenced to residual protons and 13C signals of deuterated solvents. Mass spectrometry data were collected on a Bruker
Daltons (Billerica, MA) Esquire-LC mass spectrometer equipped with ESI and VG
Autospec Tandem Mass Spectrometer equipped with FAB. Elemental analyses were performed by University of Illinois Micro Analysis Laboratory. Crystal structure analyses were done by Jered C. Garrison and Matthew Panzner.
31 Technical Details of the X-ray Structure Determinations
Crystal of 1b, 2b and 2d were coated in paraffin oil, mounted on a kryo loop and placed on a goniometer under a stream of nitrogen. X-ray data sets were collected on a
Bruker Apex CCD diffractometer with graphite-monochromated Mo KĮ radiation (Ȝ =
0.71073 Å). Unit cell determination was achieved by using reflections from three different orientations. An empirical absorption correction and other corrections were done using multi-scan SADABS. Structure solution, refinement and modeling were accomplished using the Bruker SHELXTL package.108 The structure was obtained by full-matrix least-squares refinement of F2 and the selection of appropriate atoms from the generated difference map.
Synthesis of 1,3,7,9-tetramethylxanthinium methyl sulfate95 (1a)
Caffeine (10.0 g, 51.5 mmol) was dissolved in nitrobenzene (150 mL) at 100oC for 1h. Dimethyl sulfate (10.5 mL) was added to the solution and the mixture was refluxed at 100oC for 24 h. The reaction mixture was cooled to room temperature, excess diethyl ether was added and the solvent was decanted. The residue was washed with diethyl ether several times and a white solid 1a (2.38 g, 7.43 mmol, 72 %) was obtained.
o 1 Mp: 175 C. H NMR (300 MHz, D2O): į 8.93 (s, 1H, NCHN), 4.17 (s, 3H, CH3), 4.05
13 1 (s, 3H, CH3), 3.73 (s, 3H, CH3 ), 3.35 (s, 3H, O3SOCH3 ), 3.27 (s, 3H, CH3). C { H}
NMR (75 MHz, D2O): į 154.9 (C=O), 151.8 (C=O), 140.1 (C=C), 139.8 (NCHN), 109.0
+ (C=C), 55.3 (O3SOCH3), 37.2, 36.0, 31.9, 28.8 (NCH3). ESI-MS: m/z [M ] calcd for
C10H16N4O6S 209.2, found 209.1.
32 Synthesis of 1,3,7,9-tetramethylxanthinium hexafluorophosphate (1b)
Compound 1a (1.44 g, 4.50 mmol) was dissolved in water and NH4PF6 (0.75 g,
4.6 mmol) was added. The white crystalline product 1b (1.20 g, 3.39 mmol, 76%) was
o obtained by filtration. Mp: 240 C. Anal. Calcd for C9H13F6N4O2P: C, 30.52; H, 3.70; N,
1 15.82. Found: C, 30.40; H, 3.71; N, 15.71. H NMR (300 MHz, d6-DMSO): į 9.25 (s,
1H, NCHN), 4.13 (s, 3H, CH3), 4.05 (s, 3H, CH3), 3.73 (s, 3H, CH3), 3.27 (s, 3H, CH3).
13 1 C { H} NMR (75 MHz, d6-DMSO): į 153.4 (C=O), 150.3 (C=O), 139.7 (C=C), 139.4
+ (NCHN), 107.9 (C=C), 36.8, 35.7, 31.4, 28.5 (NCH3). FAB-MS (m/z): [M ] calcd for
C9H13F6N4O2P, 209.2; found 209.0.
X-ray crystal structure analysis of 1b: formula C9H13F6N4O2P, Mw = 354.20, colorless crystal 0.20 x 0.10 x 0.02 mm, a = 12.776(1) Å, b = 6.4242(7) Å, c = 17.118(2)
Å, Į = 90°, ȕ = 111.836(2)°, Ȗ = 90°, V = 1304.1(3) Å3, Dcalc = 1.804 Mg cm-3, ȝ = 0.299
-1 mm , Z = 4, monoclinic, space group P21/c (No. 14), Ȝ = 0.71073Å, T = 100 K, Ȧ and ij scans, 8899 reflections collected, 2290 independent (Rint = 0.0236), 252 refined parameters, R1/wR2 (I 2ı(I)) = 0.0528 / 0.1249 and R1/wR2 (all data) = 0.0584 /
0.1285, maximum (minimum) residual electron density 0.779 (-0.366) e Å-3, hydrogen atoms were found from the difference map and their positions refined.
Synthesis of NHC silver(I) complex (2a)
Compound 1a (0.64 g, 2.0 mmol) was dissolved in water (72 mL) and Ag2O (0.46 g, 2.0 mmol) was added. The mixture was stirred at room temperature for 2.5 h. The brown suspension was filtered to give a colorless solution. The volatiles were removed in vacuo. Compound 2a (0.52 g, 0.82 mmol, 92%) was obtained as an off-white solid. Mp:
33 o 1 125 C. H NMR (300 MHz, D2O): į 4.21 (s, 6H, CH3), 4.13 (s, 6H, CH3), 3.82 (s, 6H,
13 1 CH3), 3.36 (s, 3H, O3SOCH3), 3.27 (s, 6H, CH3). C { H} NMR (75 MHz, D2O):į
187.1 (C-Ag), 155.0 (C=O), 152.1 (C=O), 141.1 (C=C), 110.1 (C=C), 55.6 (O3SOCH3),
+ 39.5, 38.2, 37.0, 35.9, 32.2, 31.9, 28.8 (d, CH3). ESI-MS (m/z): [M ] calcd for
C19H27AgN8O8S, 523.1; found 523.1.
Synthesis of NHC silver(I) complex (2b)
1b (1.4 g, 4.0 mmol) was dissolved in DMSO (144 mL) and Ag2O (0.93 g, 4.0 mmol) added. The mixture was stirred at 60 oC for 2.5 h to form a brown suspension.
After filtration a clear, pale brown solution was obtained. The volatile compounds were removed in vacuo to yield the brick red solid 2b (2.59 g, 3.87 mmol, 97%). Mp: 205 Co.
1 H NMR (300 MHz, d6-DMSO):į 4.15 (s, 6H, CH3), 4.01 (s, 6H, CH3), 3.72 (s, 6H,
13 1 CH3), 3.38 (s, 2H, H2O), 3.21 (s, 6H, CH3). C { H} NMR (75 MHz, d6-DMSO):į
186.6 (C-Ag), 153.0 (C=O), 150.3 (C=O), 140.2 (C=C), 108.6 (C=C), 40.1, 37.5, 31.2,
+ 27.9 (N-CH3). FAB-MS (m/z): [M ] calcd for C18H24AgF6N8O4P, 523; found 523.
X-ray crystal structure analysis of 2b: formula C32H40AgF6N8O4P, Mw = 853.56, colorless crystal 0.33 x 0.18 x 0.10 mm, a = 32.090(12) Å, b = 6.590(2) Å, c = 8.354(3)
Å, Į = 90°, ȕ = 90°, Ȗ = 90°, V = 1766.6(11) Å3, Dcalc = 1.605 Mg cm-3, ȝ = 0.697 mm-1,
Z = 2, orthorhombic, space group Imm2 (No. 44), Ȝ = 0.71073Å, T = 100 K, Ȧ and ij scans, 7814 reflections collected, 2332 independent (Rint = 0.0273), 174 refined parameters, R1/wR2 (I 2ı(I)) = 0.0294 / 0.0762 and R1/wR2 (all data) = 0.0307 /
0.0857, maximum (minimum) residual electron density 0.559 (-0.494) e Å-3, all hydrogen atoms were calculated and refined as riding atoms.
34 Synthesis of 1,3,7,9-tetramethylxanthinium nitrate (1d)
1,3,7,9- tetramethylxanthinium iodide (3.27 g, 9.72 mmol) was dissolved in 25
mL acetonitrile and AgNO3 (1.65 g, 9.72 mmol) was added. The mixture was stirred and
the yellow precipitate was filtered. After removal of the solvent, a white crystalline
product (1.56 g, 5.74 mmol, 85 %) was obtained. MP: 184- 186 oC. Anal. Calcd for
1 C9H13N4O2 : C, 39.85; H, 4.83; N, 25.82. Found: C, 39.75; H, 4.70; N, 26.14. H NMR
(300 MHz, d6-DMSO): į 9.33 (s, H, CH), 4.15 (s, 3H, CH3), 4.05 (s, 3H, CH3), 3.73 (s,
13 1 3H, CH3), 3.26 (s, 3H, CH3). C { H} NMR (75 MHz, d6-DMSO): į 153.3 (C=O),
150.2 (C=O), 139.7 (NCHN), 139.3 (C=C), 107.7 (C=C), 36.7, 35.5, 31.2, 28.3 (CH3).
ESI- MS (m/z): [M+] calcd for C9H13N4O2 209.1, found 209.1.
Synthesis of bis(1,3,7,9-tetramethylxanthine-8-ylidene)silver(I) complex with bridging nitrates (2d)
1,3,7,9-tetramethylxanthinium nitrate (1.56 g, 5.74 mmol) was dissolved in acetonitrile (100 mL) by stirring at 50- 60 oC and cooled to room temperature. Silver oxide (1.33 g, 5.74 mmol) was added. The mixture was stirred at room temperature for
2.5 h. and filtered. The volatiles were removed in vacuo. The colorless solid was recystallized in methanol/acetonitrile mixture (1:4 by volume) (0.70 g, 0.93 mmol, 32
o %). MP: 239- 241 C. Anal. Calcd for C18H24AgN10O10Ag2: C, 28.59; H, 3.20; N, 18.52.
1 Found: C, 28.58; H, 3.09; N, 18.74. H NMR (300 MHz, d6-DMSO): į 4.17 (s, 3H,
13 1 CH3), 4.02 (s, 3H, CH3), 3.74 (s, 3H, CH3), 3.24 (s, 3H, CH3). C { H} NMR (75 MHz, d6-DMSO): į 187.1 (C-Ag), 153.2 (C=O), 150.6 (C=O), 140.5 (C=C), 108.9 (C=C), 39.2,
+ + 37.8, 31.5, 28.2 (CH3). ESI- MS (m/z): 525.2 [C18H24AgN8O4] , 315.1 [C9H12AgN4O2] .
35 X-ray crystal structure analysis of 2d: formula C18H24Ag2N10O10, Mw = 756.21,
colorless crystal 0.38 x 0.11 x 0.09 mm, a = 8.4940(11) Å, b = 8.8197(12) Å, c =
9.1395(12) Å, Į = 73.089(2)°, ȕ = 66.525(2)°, Ȗ = 76.990(2)°, V = 596.18(14) Å3, Dcalc =
2.106 Mg cm-3, ȝ = 1.721 mm-1, Z = 1, triclinic, space group P-1, Ȝ = 0.71073Å, T = 100
K, Ȧ and ij scans, 5329 reflections collected, 2775 independent (Rint = 0.0274), 185 refined parameters, R1/wR2 (I 2ı(I)) = 0.0390 / 0.0982 and R1/wR2 (all data) = 0.0433
/ 0.1012, maximum (minimum) residual electron density 1.370 (-1.738) e Å-3.
36 CHAPTER III
SYNTHESIS FROM CAFFEINE OF A MIXED N- HETEROCYCLIC CARBENE-
SILVER ACETATE COMPLEX ACTIVE AGAINST RESISTANT RESPIRATORY
PATHOGENS
3.1 Introduction
Silver has been used in a variety of ways to control infections since ancient times.37 Low concentrations of silver ions kill or suppress the activity of a wide range of bacteria and fungi. This activity underlies the efficacy of silver containing products used in the treatment of burns and wounds.109 The therapeutic use of silver is well known in the form of inorganic salts and complexes, such as silver nitrate and silver sulfadiazaine and in combination with proteins.110 Elemental silver has also been used in the form of foils and nanocrystalline particles which can be found in recently developed silver-coated dressings.110,111
Silver itself has low toxicity and medically has only one rare cosmetic side effect.112,59 The toxicity of silver compounds can often be linked to the carrier molecules underscoring the importance of coordination of silver to other nontoxic molecules for the safe use as antimicrobials. Biologically relevant molecules known to have minimal in vivo toxicity, such as xanthine derivatives, may be excellent candidates for this purpose.
37 We are interested in the synthesis of silver xanthine complexes that have the potential to be used as a new class of antibiotics, particularly for the treatment of lung infections seen in cystic fibrosis (CF) patients. CF is a life threatening genetic disorder which results from mutations in the cystic fibrosis transmembrane regulator (CFTR) gene and affects approximately 60,000 people world wide. Chronic pulmonary infections with
Pseudomonas aeruginosa, Staphylococcus aureus and Burkholderia cepacia complex
(Bcc) organisms cause most of the morbidity and mortality in patients with CF.91
Xanthines have been used medicinally as diuretics, central nervous system stimulants and inhibitors of cyclic adenosine monophosphate (cAMP) phosphodiesterase resulting in airway smooth muscle relaxation.113 Caffeine is a xanthine derivative that is readily available and has low toxicity, and thus, is a good candidate for a carrier molecule for the delivery of silver cations to the lungs.
In the previous chapter, the synthesis of methylated caffeine with various counter ions, and the formation of its biscarbene silver complexes by in situ deprotonation with silver oxide was reported.31 The use of silver oxide to deprotonate imidazolium salts is one of the most common procedures used for the synthesis of NHC silver complexes.26
We have also shown the effective antimicrobial properties of NHC silver complexes obtained by this method.75,77 Herein we report the synthesis and characterization of the methylated caffeine 1 and silver complexes 3 and 4 derived from 1 and the antimicrobial properties of 1 and 4 (Figure 3.1).
38 CH O 3 O CH3 H3C O CH3 CH CH N 3 3 N N N O I- N N Ag O O N N O N N N N O O CH CH3 CH H C CH3 3 CH3 3 3 CH3
3 1
O CH3 CH3 O N N . Ag O C CH3 2H2O O N N CH CH3 3
4
Figure 3.1 Methylated caffeine iodide salt and silver complexes
3.2 Results and Discussion
Methylated caffeine, 1,3,7,9-tetramethylxanthinium iodide, 1, was synthesized by refluxing caffeine with an excess of methyl iodide in DMF using a modified literature procedure (Scheme 3.1).98 Compound 1 is a water-soluble solid and stable in air up to its melting point. In the 1H NMR spectrum, the imidazolium proton appears at 9.30 ppm, which is consistent with the general C-H acidic proton shift of imidazolium salts (d = 8-
10 ppm).11,12 The imidazolium carbon appears at 139.6 ppm as the most notable feature in the 13C NMR spectrum.
39 O CH3 O CH3 CH3 CH3 N N N CH3I N I- DMF O N N O N N CH CH3 CH3 3 1
Scheme 3.1 Synthesis of 1
Compound 1 was combined with an excess of silver oxide in methanol. In the 1H
NMR spectrum of the product, the lack of the resonance of the imidazolium proton and the downfield shifted methyl protons were observed as indications for the formation of an
NHC silver complex. However, the carbene carbon resonance, which is one of the most notable features for the formation of an NHC silver complex in the 13C NMR, was not observed. This can be attributed to the dynamic behavior of the complex in solution as well as the poor relaxation of the quaternary carbene carbon.18,23 There are several NHC silver complexes which exhibit this behavior that have been reported in the literature.13
ESI- MS data showed the bis(NHC) silver molecular cation at mass 523.1 and its related fragments in the positive mode but the iodide was not observed in the negative mode.
The single crystals grown from a concentrated methanol solution of this complex showed the formation of methyl carbonate anion, 3. This can be explained by the reaction of carbon dioxide in air with the methoxide created in the silver oxide methanol mixture
(Scheme 3.2). There are several literature examples that show bases promote the reaction of primary alcohols with carbon dioxide to give organic carbonates in high yields.114
40 CH O 3 H C CH3 O CH3 3 O CH CH N Ag O 3 3 N - 2 N N I X N N Ag - O N N CH3OH I O N N N N O CH CH3 3 CH H C CH3 3 3 CH3 1 2
Ag 2 O, C CH O 3 OH 2 O CH3 H3C O CH3 CH3 N N N N O Ag O O N N N N O O CH H C CH3 CH3 3 3 CH3
3
H2O/ CH3CO2C2H5
O CH3 CH3 O N N . Ag O C CH3 2H2O O N N CH CH3 3
4
Scheme 3.2 Formation of 3 and 4
When 3 was dissolved in ethanol, methanol or water and ethyl acetate, and the solvent mixture slowly allowed to evaporate, complex 4 was formed. This complex attracted our attention for several reasons. Complex 4 is composed of biologically relevant ligands and is water soluble. These properties make 4 a viable candidate for use as an internal antimicrobial. Furthermore, 4 is a relatively small molecule and may be
41 able to diffuse into the bacteria trapping thick mucus layer in the lungs of CF patients better than conventional larger antibiotics.115 For these reasons we explored the direct
synthesis of 4. In situ deprotonation of 1 with silver acetate24 in 1:2 ratio in methanol gave complex 4 (Scheme 3.3). The disappearance of the resonance for the imidazolium proton of 1 and the appearance of the resonance for the carbene carbon atom at 186.2 ppm together with carbonyl and methyl carbons of the acetate group at 176.2 ppm and
23.1 ppm, respectively showed the formation of the expected NHC silver acetate complex. Complex 4 has good stability in water. A water solution of 4 kept in the dark was observed to form silver(0) particles within 10 days.
CH O CH3 O 3 CH CH3 3 O N N AgCO2CH3 N N - . I Ag O C CH3 2H2O CH OH O N N 3 O N N
CH CH3 CH3 3 CH3
1 4
Scheme 3.3 The direct synthesis of 4
Single crystal X-ray diffraction data was collected for 1, 3 and 4. Single crystals of 1 were obtained by slow evaporation of a concentrated acetonitrile solution (Figure
3.2). Crystals of 3 suitable for single crystal x-ray diffraction studies were grown from a concentrated sample in methanol (Figure 3.3). The asymmetric unit contains the biscarbene methylated caffeine silver complex, a methyl carbonate anion and three solvent methanol molecules. The cation of complex 3 is planar with an average
42 silver carbene bond distance of 2.094(4)Å. The carbene-Ag-carbene bond angle is
170.83(15)° which deviates significantly from the linear geometry expected for the complex.
Figure 3.2 Molecular structure of 1. Thermal ellipsoids are drawn at 50% probability.
Figure 3.3 Molecular structure of 3. Thermal ellipsoids are drawn at 50% probability. Hydrogen atoms have been omitted for clarity
43 Colorless crystals of 4 were obtained from a concentrated sample in a water/ethyl acetate mixture (Figure 3.4). The asymmetric unit of this molecule contains the complex together with two molecules of water. The geometry around the silver atom deviates significantly from linearity with a C1-Ag1-O3 bond angle of 168.19(9)o. The Ag-carbene bond length, 2.067(3) Å in 4 is shorter than those in complex 3 (Table 3.1).
Figure 3.4 Molecular structure of 4. Thermal ellipsoids are drawn at 50% probability. Hydrogen atoms have been omitted for clarity
Bond Lengths 1 3 4 and Angles
N1-C1 1.317(2) Å 1.378(5) Å 1.343(3) Å
N2-C1 1.349(2) Å 1.334(5) Å 1.376(3) Å
N1-C1-N2 110.77(13)o 105.5(3)o 105.5(2)o
C1-Ag1 - 2.096(4) Å 2.067(3) Å
C1-Ag1-C10 - 170.83(15)o -
C1-Ag1-O3 - - 168.19(9) o
Table 3.1 Selected bond lengths and angles for 1, 3 and 4
44 The in vitro antimicrobial activity of methylated caffeine and its silver complex was evaluated against bacterial and fungal strains. The test organisms included
Escherichia coli and Pseudomonas aeruginosa as representative gram-negative bacteria, and Staphylococcus aureus as a gram-positive bacterium. Candida albicans, Aspergillus niger and Saccharomycetes cerevisiae were used as the representative fungi. Methylated caffeine 1 itself had a bacteriostatic effect on the chosen bacteria with minimal inhibitory concentrations (MIC) of 100 mg/mL for S. aureus and 50 mg/mL for both E. coli and P. aeruginosa by the broth macrodilution method. The fungistatic MIC values for 1 were found to be 150 mg/mL for C. albicans and S. cerevisiae, and 75 mg/mL for A. niger.
Several N,N’-disubstituted imidazolium salts, referred to as quaternary ammonium compounds (QAC), have already been shown to have antimicrobial properties.116 The silver complex 4 was found to be a very effective antimicrobial agent when tested on fungi. Against A. niger and S. cerevisiae, 4 was found to be effective with a fungicidal
MIC values of 13 mg/mL and 4 mg/mL. It shows a fungistatic effect on C. albicans with a MIC value of 4 mg/mL. Caffeine is a base analogue that is known to induce mutations in both fungi and bacteria by directly binding to DNA and through inhibition of normal cycle-cycle checkpoint functions through incompletely understood mechanisms. 117
The antimicrobial activity of the silver complex, 4, was evaluated against a variety of test organisms including a panel of highly resistant opportunistic pathogens recovered, primarily, from the respiratory tract of patients with cystic fibrosis (CF).
These studies were done by Lisa A. Hogue, Rebekah J. Mallett, Christine E. Hovis,
Marvin Coughenour and Carolyn L. Cannon in Washington University School of
45 Medicine. The following three paragraphs, tables and figures were provided by Carolyn
L. Cannon.
Using National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution methods, the MIC of complex 4 was found to range from 1 to 10 mg/mL for all bacterial strains tested (Table 3.2). As positive and negative controls, the MIC for complex 4 against E. coli J53 strains with and without the silver resistant plasmid pMG101 were tested. This plasmid contains open reading frames for silP, silA, silB, silC, silR, silS and silE silver resistance genes originally cloned from a silver nitrate resistant burn ward Salmonella isolate.48,70 The MIC for J53 lacking the plasmid was less than 1 mg/mL, whereas the MIC of 4 for J53 containing pMG101 was greater or equal to
5 mg/mL demonstrating again, that the antimicrobial activity of complex 4 is primarily due to the silver moiety.
46 Table 3.2 Micro-dilution MIC testing of complex 4. Micro-dilution. Strains kindly provided by a. American Type Culture Collection. b. Dr. Gerald Pier, Boston, MA. c. Dr. Thomas Ferkol, St. Louis, MO. d. Dr. John LiPuma, Ann Arbor, MI. eSt. Louis Children’s Hospital, Clinical Microbiology. f. Dr. Johannes Huebner, Boston, MA. g. Dr. Simon Silver, Chicago, IL. 47 The activity of complex 4 against the panel of respiratory pathogens tested in
Table 3.2 varied with the growth media of the bacteria (Figure 3.5). The mean MIC of complex 4 for this group of pathogens grown in Mueller-Hinton (M-H) was 3.1 ± 0.4 mg/mL (SEM), whereas the mean MIC for the same bacteria grown in Luria broth (LB) was 5.0 ± 0.5 mg/mL (SEM). This difference in MIC was not due to differences in the growth rate of the tested bacteria in the two different enriched media (data not shown).
Rather, the differences may be due to differences in the free Ag+ concentration in each of the media. Both M-H and LB are high ionic strength enriched media with reported conductivities of 102 and 112, respectively.118 The antimicrobial activity of the
aminoglycoside antibiotics is known to be exquisitely sensitive to the nature of the media
used to determine the MIC 119,120 with high ionic strength media acting to antagonize
aminoglycoside activity. Although not documented, one hypothesis used to explain the
observed differences in MICs in different media may be due to differences in the activity
of efflux pumps that extrude the aminoglycosides.118 Unidentified Ag+ efflux pumps in these respiratory pathogens may exhibit different activity in M-H versus LB. If such pumps exist, they may underlie the unstable silver sulfadiazine resistance seen in reported resistant burn ward P. aeruginosa isolates.121,67 Analogous P-type ATPase pumps have recently been identified that allow adaptation to copper stress by P. aeruginosa.122
Alternatively, the differences in MIC may be due to differences in either stability of the complex 4 molecule in each environment causing different rates of Ag+ release, or differences in complexation of Ag+ to protein components of the different media.
Whatever the explanation, the observed differences are modest and do not predict large differences in MIC in the in vivo setting.
48 ** 5
4
3
2
1
0 M-H LB Growth media Figure 3.5 A comparison of the MIC determinations in M-H broth versus LB of the pathogens tested in Table 3.2 excluding the E. coli control organisms, shows a statistically significant difference (two-tailed t test, **p = 0.0045, n = 34). Data are displayed as mean and SEM (Prism 4, GraphPad).
The mechanism of action of complex 4 is currently unknown, as is the
mechanism of action of silver cations. To begin to understand the mechanism of its
antimicrobial effects, complex 4 was applied to B. dolosa and transmission electron microscopy of the treated bacteria was compared with untreated cells. The complex 4 treated bacteria demonstrated disruption of the bacterial cell morphology characterized by cell “ghosts” devoid of cytoplasm. The “ghost” cell membranes were studded with numerous electron dense clusters likely representing outer membrane deposition of silver salts (Figure 3.6), as has been reported by Sondi and Salopek-Sondi after treatment of E. coli with silver nanoparticles.123 The jagged edges of the cell in the complex 4 treated bacteria may indicate breakdown of the structural integrity of the cell membrane or may simply be an artifact of the sectioning for TEM. Even if partially an artifact, none of the untreated cells exhibited this morphology implicating an effect of the complex 4 treatment.
49 A B
1 µm
Figure 3.6 Effects of complex 4 on respiratory pathogens. TEM of B. dolosa strain AU4459 before (A) and after (B) application of 5 mg/mL complex 4 in Luria broth for 1 hour at 37°C.
Preliminary in vitro toxicity studies were performed on primary cultures of murine tracheal epithelial cells (MTECs) in order to test the potential transcriptional effects of the Ag+ component of complex 4 as a nebulized antimicrobial as compared to those of the carrier compound 1. These studies were done and the following paragraph and figure was provided by Seth D. Crosby, Washington University, School Medicine.
In the first experiment, MTEC cultures were incubated for 24 hours with either 1 or 10 mg/mL complex 4, or 10 mg/mL compound 1 dissolved in media. The MTEC cells were lysed, RNA isolated, labeled (Genisphere A350) and samples to be compared were co-hybridized to microarray slides containing probes which represented the entire mouse transcriptome to allow for transcriptional profiling. The pairs of samples applied to the arrays were 1 mg/mL complex 4 co-hybridized with 10 mg/ml compound 1 and 10 mg/mL complex 4 co-hybridized with 10 mg/mL compound 1 with technical replicate per sample pair after dye swapping. Of the few genes that demonstrated >2-fold expression
50 difference (Figure 3.7A) 5 genes and 22 genes out of a possible 25K were significantly
(p<0.05) disregulated within the first and second pairs of samples, respectively. There was no overlap between these two sets of genes (Figure 3.6B). We performed a second experiment to produce a biological replicate and to look for effects at higher concentrations of complex 4. MTECs were incubated with either 10 mg/mL complex 4
again, 100 mg/mL complex 4 or 10 mg/mL compound 1, lysed, RNA isolated and labeled with a more sensitive dendrimer system (Genisphere A900) before co-hybridization to the spotted arrays. The 10 mg/mL complex 4 co-hybridized with 10 mg/ml compound 1
pair exhibited only 12 genes with expression changes greater than 2 fold. None of these
12 genes corresponded to any of the 22 genes that were seen in the first experiment with
the same concentration pair of 1 and 4 (Figure 3.7B). The 100 mg/mL complex 4 co-
hybridized with 10 mg/mL compound 1 pair resulted in 2-fold expression changes in 81
genes. One gene, Trim30 (Genbank NM_009099), was down regulated in this latter
pairing (fold change 0.39), as well as in the first experiment 10 mg/mL complex 4 versus
10 mg/mL compound 1 pair (fold change 0.49). However, this same gene was noted to be
down regulated in a 10 mg/mL methylated caffine compound 1 versus media alone pair
(fold change 0.397) and thus, is most likely due to an effect of the parent compound on
respiratory epithelial cells rather than an effect of silver cations. Thus, silver treatment of
MTECs caused no significant consistent transcriptional change at any concentration
tested. Nor were there any dose responsive genes among the small, likely insignificant,
number that did appear to be >2-fold altered.
51 Figure 3.7 Transcriptional profiling of murine tracheal epithelial cells (METCs) treated with complex 4 shows no significant gene expression changes. Murine tracheal epithelial cells (MTECs) isolated from C57Bl/6 animals and grown to confluency on Transwells were incubated with the indicated concentration of either the methylated caffeine parent compound 2 or the silver complex 4 for 24 hours. The RNA was harvested, cDNA synthesized and labeled. The labeled cDNA was hybridized to the MEEBO (Mouse Exonic Evidence Based Oligonucleotide) collection of probes124 representing over 25,000 mouse genes printed on glass slides. The slides were scanned and intensity values imported into GeneSpring 7.2 software for analysis. The intensity values correlate with expression levels of individual genes, which are displayed as dots on the log-scale scatter plots (A) that compare the expression level of each gene in the cells treated with either 1 mg/mL or 10 mg/mL complex 4 versus 10 mg/mL compound 2. The 10 mg/mL complex 4 treatment induced statistically significant (p<0.05) change in expression of 2-fold in only 22 genes. These gene expression changes were not reproduced in a second experiment, which showed changes in only 12 genes, all of which were different from the 22 found in the first experiment (B). Of the genes showing expression changes, most were repressed.
Preliminary toxicity studies on a small number of rats showed that methylated caffeine, 1, administered intravenously, has low toxicity with an LD50 (50 % lethal concentration) of 1068 mg/kg. The kidneys, livers, adrenals and hearts of the
52 experimental rats appeared normal upon autopsy. A study using the silver complex 4 was also performed. Because 4 decomposes in the presence of chloride ions, it was dissolved in water instead of saline. The amount injected was limited due to the solubility of the complex in water, which is 11.6 mg/mL. No adverse effects were noted after the injections.
3.3 Conclusion
We have synthesized a novel mixed N-heterocyclic carbene-acetate complex of silver from caffeine. We determined that both the silver complex and the methylated caffeine parent compound exhibit antimicrobial properties. In addition to its antifungal activity and activity against selected gram-negative and gram-positive bacteria, the NHC silver complex derived from methylated caffeine demonstrated antimicrobial activity against numerous resistant respiratory pathogens including members of the Burkholderia cepacia complex. Transcriptional profiling of murine tracheal epithelial cells treated with the silver complex and the methylated caffeine parent compound showed no significant gene expression changes. Preliminary in vivo toxicity studies demonstrated very low toxicity for both the parent methylated caffeine and the silver complex. Given the water solubility of this silver complex and its low toxicity, it may prove useful as a nebulized therapy in patients colonized with these resistant organisms. We are currently exploring the synthesis of other silver xanthine complexes having different groups on the imidazole ring to enable higher water solubility.
53 3.4 Experimental
General Methods
All manipulations were carried out in air. Caffeine and methyl iodide were purchased from Acros. Silver acetate was purchased from Aldrich. LB Broth, Miller and
Bactor agar were purchased from DIFCO. 1H and 13C NMR data were recorded on a
Gemini 300 MHz instrument and were referenced to residual protons and 13C signals of
deuterated solvents. 109Ag NMR data was recorded on a Unity Inova 750 MHz
instrument and AgNO3 in d6-DMSO was used as an external reference. Mass
spectrometry data were collected on a Bruker Daltons (Billerica, MA) Esquire-LC mass
spectrometer equipped with ESI. Elemental analyses were performed by University of
Illinois Micro Analysis Laboratory. Crystal structure analyses were done by Matthew
Panzner and Semih Durmus. Antimicrobial studies were performed by Lisa A. Hogue,
Rebekah J. Mallett, Christine E. Hovis, Marvin Coughenour and Carolyn L. Cannon,
Division of Allergy and Pulmonary Medicine, Department of Pediatrics, Washington
University School of Medicine, St. Louis. Transcriptional profiling of murine tracheal
epithelial cells was done by Seth D. Crosby, Genome Sequencing Center, Washington
University, School Medicine, St. Louis. LD50 studies were done by Khadijah Hindi in the
biology department, The University of Akron.
Technical Details of the X-ray Structure Determinations
Crystals of 1, 3 and 4 were coated in paraffin oil, mounted on a kryo loop and
placed on a goniometer under a stream of nitrogen. X-ray data sets were collected on a
Bruker Apex CCD diffractometer with graphite-monochromated Mo KĮ radiation (Ȝ =
54 0.71073 Å). Unit cell determination was achieved by using reflections from three different orientations. An empirical absorption correction and other corrections were done using multi-scan SADABS. Structure solution, refinement and modeling were accomplished using the Bruker SHELXTL package.108 The structure was obtained by full-matrix least-squares refinement of F2 and the selection of appropriate atoms from the generated difference map.
Synthesis of 1,3,7,9- tetramethylxanthinium iodide(1)
Caffeine (9.00 g, 46.4 mmol) was refluxed with methyl iodide (15 mL) in N, N’- dimethyl formamide (50 mL) at 145 oC for 20 hours. An excess amount of acetone was added to the clear solution obtained and the precipitate filtered and washed with acetone.
Crystallization from acetonitrile gave 1 as a yellowish white solid (19.4 mmol, 6.52 g, 42
o %). Mp: 187-190 C. Anal. Calcd for C9H13IN4O2.H2O: C, 30.52; H, 4.27; N, 15.82.
1 Found: C, 30.27; H, 4.18; N, 15.41. H NMR (300 MHz, d6-DMSO): į 9.30 (s, 1H,
13 NCHN), 4.16 (s, 3H, CH3), 4.06 (s, 3H, CH3), 3.75 (s, 3H, CH3), 3.28 (s, 3H, CH3). C
1 { H} NMR (75 MHz, d6-DMSO): į 153.3 (C=O), 150.2 (C=O), 139.6 (NCHN),
139.3(C=C), 107.8 (C=C), 36.9, 35.6, 31.4, 28.4 (NCH3). ESI-MS (m/z): 209
+ [C9H13N4O2 ]. X-ray crystal structure analysis of 1: formula C9H15IN4O3, Mw = 354.15, colorless crystal 0.40 x 0.40 x 0.30 mm, a = 7.8807(5) Å, b = 8.1331(6) Å, c =
10.8982(7) Å, Į = 96.4480(10)°, ȕ = 99.4090(10)°, Ȗ = 110.5710(10)°, V = 634.19(7) Å3,
Dcalc = 1.855 Mg.m-3, ȝ = 2.529 mm-1, Z = 2, triclinic, space group P-1, Ȝ = 0.71073 Å, T
= 100 K, Ȧ and ij scans, 5638 reflections collected, 2944 independent (Rint = 0.0123), 166
55 refined parameters, R1/wR2 (I 2ı(I)) = 0.0148/ 0.0372 and R1/wR2 (all data) = 0.0152/
0.0374, maximum (minimum) residual electron density 0.465(-0.291) e.Å-3.
Synthesis of bis(1,3,7,9-tetramethylxanthine-8-ylidene)silver methyl carbonate (3)
Compound 1 (0.68 g, 2.0 mmol) was dissolved in methanol (72 mL) and Ag2O
(0.70 g, 3.0 mmol) was added. The mixture was stirred at room temperature in the dark for 2 h 25 min. The dark gray suspension was filtered to give a colorless solution. The volatiles were removed in vacuo. Compound 3 (0.55 g, 0.85 mmol, 85 %) was obtained
o as a brownish solid. Mp: 120-123 C. Anal. Calcd for C20H27AgN8O7: C, 40.08; H, 4.54;
1 N, 18.70. Found: C, 39.39; H, 4.57; N, 19.06. H NMR (300 MHz, d6-DMSO): į 4.20 (s,
6H, CH3), 4.07 (s, 6H, CH3), 3.75 (s, 6H, CH3), 3.31 (s, 2H, H2O), 3.29 (s, 3H, CH3), 3.26
13 1 (s, 6H, CH3). C { H} NMR (75 MHz, d6-DMSO):į 161.0 (C=O), 152.3 (C=O), 150.4
(C=O), 140.4 (C=C), 108.7 (C=C), 54.4 (CH3 ), 36.9, 31.7, 30.2, 27.7 (CH3). ESI-MS
+ + + (m/z): 523.1 [C18H24AgN8O4 ], 314.8 [C9H12AgN4O2 ], 208.9 [C9H13N4O2 ]. X-ray crystal structure analysis of 3: formula C23H39AgN8O10, Mw = 695.49, colorless crystal
0.33 x 0.28 x 0.08 mm, a = 8.0385(10) Å, b = 9.1589(12) Å, c = 20.262(3) Å, Į =
88.876(2)°, ȕ = 78.611(2)°, Ȗ = 75.225(2)°, V = 1413.3(3) Å3, Dcalc = 1.634 Mg cm-3, ȝ
= 0.783 mm-1, Z = 2, triclinic, space group P-1 (No. 2), Ȝ = 0.71073Å, T = 100 K, Ȧ and
ij scans, 12637 reflections collected, 6599 independent (Rint= 0.0342), 394 refined parameters, R1/wR2 (I 2ı(I)) = 0.0568 / 0.1464 and R1/wR2 (all data) = 0.0638/
0.1512, maximum (minimum) residual electron density 2.330 (-1.920) e Å-3, all hydrogen atoms were calculated and refined as riding atoms.
56 Synthesis of (1,3,7,9-tetramethylxanthine-8-ylidene)silveracetate (4)
Compound 1 (4.00 mmol, 1.34 g) was dissolved in methanol (100 mL) and silver acetate (8.00 mmol, 1.34 g) was added. The mixture was stirred at room temperature for
40 min. The yellow silver iodide suspension was filtered to give a colorless solution. The volatiles were removed in vacuo. Compound 4 (1.22 mmol, 0.5 g, 30%) was obtained as a white solid after recrystallization from ethanol. Mp: 209-212oC. Anal. Calcd for
C11H15AgN4O4.2H2O: C, 32.11; H, 4.62; N, 13.62. Found: C, 31.95; H, 4.33; N, 13.18.
1 H NMR (300 MHz, D2O): į 4.19 (s, 3H, CH3), 4.07 (s, 3H, CH3), 3.82 (s, 3H, CH3),
13 1 3.34 (s, 3H, CH3), 1.91 (s, 3H, COCH3). C { H} NMR (75 MHz, DMSO):į 186.2 (C-
Ag), 176.2 (C=O), 153.9 (C=O), 151.3 (C=O), 141.2 (C=C), 109.6 (C=C), 37.8, 31.4,
109 29.7 (N-CH3), 23.1 (COCH3). Ag NMR: 409.53 (broad C-Ag). ESI-MS (m/z): 523
+ + + [C18H24AgN8O4 ], 315 [C9H12AgN4O2 ], 209 [C9H13N4O2 ]. X-ray crystal structure analysis of 4: formula C11N4O6H19Ag, Mw = 411.16, colorless crystal 0.21 x 0.18 x 0.03 mm, a = 8.4027(8)Å, b = 6.2961(6) Å, c = 14.1856(14) Å, Į = 90°, ȕ = 98.243(2)°, Ȗ =
90°, V = 742.73(12) Å3, Dcalc = 1.839 Mg.m-3,ȝ = 1.393 mm-1, Z = 2, monoclinic, space group P21/m, Ȝ = 0.71073Å, T = 100 K, Ȧ and ij scans, 6661 reflections collected, 1940 independent (Rint = 0.0200), 150 refined parameters, R1/wR2 (I 2ı(I)) = 0.0244/0.0598 and R1/wR2 (all data) = 0.0256/0.0604, maximum (minimum) residual electron density
1.593 (-0.229) e.Å-3.
In vitro antimicrobial activity
The MIC was determined by both the broth macro- and micro-dilution methods.
For the macro-dilution MIC testing of fungi, 5 mL of sterilized LB broth was inoculated
57 with stationary phase fungi and grown for 72 hours at room temperature without shaking.
Serial dilutions of freshly prepared 1 or 4 in culture tubes were inoculated with a constant
volume of the cultures of fungi and incubated for 72 hours at room temperature. The
MIC was determined by visual inspection of the tubes for growth.
The micro-broth dilution MIC determination was performed using a standard
NCCLS protocol.125,76 Bacteria are streaked from glycerol-frozen stocks onto blood agar plates and incubated overnight at 37°C. Cells from the fresh plates are suspended in either Luria broth or the NCCLS standard Mueller-Hinton broth to an OD650 of 0.25 and
8 grown in a shaking incubator until the OD650 is 0.4, which corresponds to ~2 x 10
CFU/mL, confirmed by plating serial dilutions. The bacteria are diluted in broth to a concentration corresponding to 105 CFU in 100 mL, which is added to triplicate well of a
96 well plate containing 100 mL of the complex 4 concentration to be tested. The plate is incubated for 18 hours at 37°C and MIC determined as the lowest concentration with clear wells.
Cell culture
We used a modification of the method published by You and colleagues to isolate primary murine airway epithelial cells and establish cultures.126 Briefly, immediately after CO2 euthanasia of the C57Bl/6J mice, tracheae were isolated and collected in Ham’s
F-12 medium with 100 U/ml penicillin and 100 µg/mL streptomycin (Ham’s F-12/pen- strep) held at 4°C. Each trachea was stripped of overlying tissue, cut lengthwise and rinsed twice with Ham’s F-12/pen-strep. Tracheae were placed in a clean 15 ml tube, pronase (Roche Molecular Biochemicals, Indianapolis, IN) was added (0.15%) to Ham’s
58 F-12/pen-strep and the tracheae were incubated overnight at 4°C. The tube was gently inverted several times to dislodge cells. Fetal calf serum (10%) was added to halt enzymatic digestion prior to more gentle agitation and wash steps to release cells. The cell suspensions pooled from all of the animals were pelleted at ~400 g for 10 min at 4°C, resuspended in Ham’s F-12/pen-strep with 0.5 mg/ml crude pancreatic DNase I (Sigma-
Aldrich) and incubated on ice for 5 minutes followed by centrifugation at ~400 g for 5 min at 4°C. Removed the supernatant and resuspended the cells in 1:1 DMEM:Ham’s
F12 medium (vol:vol) with 100 U/ml penicillin, 100 µg/mL streptomycin, 0.25 µg/mL fungizione, 15 mM HEPES, 4 mM L-glutamine and 3.6 mM NaHCO3 (MTEC Basic
medium) supplemented with 10 µg/mL insulin, 5 µg/mL transferrin, 0.1 µg/ml cholera
toxin, 25 ng/mL epidermal growth factor (Becton-Dickinson, Bedford, MA), 30 µg/mL
bovine pituitary extract and 5% fetal calf serum. The resuspended cells were seeded at
low density on semi-permeable membranes (Transwell) of 6 well plates coated with
collagen. Approximately 4 x 105 cells, recovered from ~2 trachea, were seeded per individual well, which were then placed in a humidified incubator at 37°C in 5% CO2 for
7 days. After the cells established tight junctions and a high trans-membrane resistance
(>1000 mOhms•cm2), media was removed from the upper chamber, along with any non- adherent cells and debris, to create an air-liquid interface (ALI). The medium in the bottom chamber was also removed, and replaced with MTEC Basic medium supplemented with 2% NuSerum(Becton-Dickinson) and 10-8 M retinoic acid. The medium was replaced twice weekly. Primary cultures remained viable for up to 80 days.
Cells became differentiated in this defined media under ALI conditions and developed
59 characteristics of epithelial cells in the airways including a ciliated and non-ciliated population. Multiple layers were present including basal cells.
Transmission electron microscopy
Bacteria to be examined by transmission electron microscopy (TEM) were pelleted, fixed in 2.5% glutaraldehyde in 0.1 M sodium cacodylate for one hour at 4°C, washed for 20 minutes three times in 0.1 M sodium cacodylate, and then incubated with
1.25% osmium tetroxide in PBS for 90 minutes at 25°C. Samples were further fixed in
4% uranyl acetate, thin-sectioned (90 nm) in Polybed 812 (Polysciences, Warrington,
PA), poststained in uranyl acetate and lead citrate, then visualized on a Zeiss
902 microscope (Zeiss, Thornwood, NY) and recorded on electron microscopy film.
Microarray gene expression analysis
The microarrays used were created from the publically available MEEBO (Mouse
Exonic Evidence Based Oligonucleotide) collection of probes representing greater than
25,000 mouse genes124 (Invitrogen) printed out of 3xSSC with 0.75 M betaine buffer onto epoxysilane slides (Corning). Murine tracheal epithelial cells (MTECs) isolated from
C57Bl/6 animals, grown to confluency and allowed to differentiate at an air liquid interface for 21 days were incubated at 37°C with either methylated caffeine, 1 or complex 4 in 1 ml of media applied to the apical surface for 24 hours. The inserts were rinsed with PBS and the total RNA isolated using the RNeasy Mini Kit (Qiagen). The
RNA was quantified spectrophotometrically and the RNA quality assured through visualization on glyoxyl gels and analysis on an Agilent bioanalyzer 2100. Starting with
2 or 8 µg of total RNA, first strand cDNA was generated by modified oligo(dT)-primed
60 reverse transcription (Superscript II; Invitrogen) utilizing the 3DNA Array 350 kit or the
3DNA Array 900 kit, respectively (Genisphere). The 3DNA dT primers bear a capture sequence on the 5' end. Two hybridizations were carried out in a sequential manner. The primary hybridization was performed by adding cDNA to the microarray which was incubated at 63°C for 16–20 h. A second hybridization was carried out using the fluorescent dendrimers (Genishpere) which contain oligos complementary to the capture sequence in the dT primers. To create technical replicates for each condition, RNAs were divided into two samples. These samples were independently labeled with each dye, either Cy5 or Cy3 to allow for dye-swapping. Thus, two DNA microarrays were scanned for each sample pair tested.
Slides were scanned immediately after hybridization in a PerkinElmer ScanArray
Express HT scanner to detect Cy3 and Cy5 fluorescence. Laser power was kept constant for the scans, and photomultiplier tube values were set for optimal intensity with minimal background. The intensity values are imported into GeneSpring 7.2 software (Agilent,
Redwood city, CA) for analysis. Local background intensity was subtracted from individual spot intensities. To account for the dye swap, the “signal” channel and
“control” channel measurements were reversed in those samples so that signal derived from methylated caffeine-treated RNA occupies the control channel and complex 4 treated RNA the signal channel. A Lowess curve was fit to the log-intensity versus log- ratio plot. 20.0% of the data was used to calculate the Lowess fit at each point. This curve was used to adjust the control value for each measurement. If the control channel was lower than 10 RFU then 10 was used instead. The mean signal to Lowess adjusted controlled ratios were calculated. The cross-chip averages were derived from the antilog
61 of the mean of the natural log ratios across the two microarrays. Oligonucleotide elements derived from mouse elements that received a "present" call (intensity > 200RFU or local signal-to-background > 2 in either channel) by the ScanArray software were identified and all others were excluded from the analysis. Data were filtered using a one- sample T-test (p<0.05) and a 2-fold cut-off.
Animal Studies
Male C57/Bl6 mice were housed in the Clinical Sciences Research building animal facility managed by veterinarians associated with Washington University School of Medicine. All procedures involving mice were approved by the Washington University
Animal Studies Committee.
Male Sprague Dawley (Harlan Sprague Dawley, Indianapolis, IN) adult rats (500 g average body weight) were housed in the University of Akron animal facility.
Temperature and humidity were held constant, and a standard light cycle (12 hours light/12 hours dark) was used. Food (Lab diet 5P00, Prolab, PMI nutrition, Intl.,
Bretwood, MO) and water were provided ad libitum. Animals were anesthetized with ether to inject the compound into the tail vein, using a 26 3/8 gauge syringe needle in a volume of 0.3 mL sterile saline. The concentrations of the ligand ranged from 5.3 mg/kg to 1068 mg/kg. At the end dosages of the experiment, animals were terminated, and the liver, lung, kidney, and heart tissues were removed and frozen at -70 °C for 24 hours.
Urine samples were collected using metabolic cages for later examination of the compound distribution.
62 CHAPTER IV
SYNTHESIS OF N- HETEROCYCLIC CARBENE SILVER ACETATE COMPLEXES
FROM THEOPHYLLINE DERIVATIVES AND ANTIMICROBIAL ACTIVITY
AGAINST RESISTANT RESPIRATORY PATHOGENS
4.1 Introduction
Theophylline is one of the xanthine derivatives which is similar to caffeine in
terms of both structure and pharmacological effects. It is the main xanthine used
clinically for chronic respiratory diseases such as asthma and chronic obstructive
pulmonary disease (COPD).127 It is known to have a bronchodilating and a mild anti- inflammatory effect and believed to nonselectively inhibit the activity of the enzymes called phosphodiesterases (PDE) which results in airway smooth muscle relaxation. 128,129
Several derivatives of theophylline such as ethylenediamine salt called aminophylline and
N-7 substituted derivatives have been also explored to increase the water solubility and
lessen the side effects associated with the narrow therapeutic window of theophylline.130
For example, 7-(2,3-dihydroxypropyl)theophylline, also known as dyphylline is less toxic than theophylline and used in the management of bronchial asthma.130b, 4d, 131
63 The promising activity of previously synthesized silver(I) acetate complex of methylated caffeine against resistant respiratory pathogens132 has encouraged us to look
for other methylxanthine derivatives as the potential carbon donor ligands. Among the
N-7 substituted derivatives of theophylline: 2-hydroxyethyl (A), 2,3-dihydroxypropyl
(B), and acetic acid methyl ester (C) substituted ones would be very good precursors to
synthesize NHC silver(I) acetate complexes having increased water solubility than the
methylated caffeine analogue (Figure 4.1). These derivatives are readily available
compounds. Particularly, A and B have been found to be less toxic than caffeine
130b,131,133 and can potentially be good molecules for carrying the silver cations to the lungs.
O H 6 5 H3C N 7 1N 8 O 2 4 N N3 9
CH3 Theophylline
CH OH OH O 3 O O O H C OH H3C N O 3 N H3C N N N N
O N O N N O N N N CH CH3 3 CH3 A B C
Figure 4.1 Theophylline and N-7 substituted derivatives
64 Formation of several methylated imidazolium cations from N-7 substituted theophyllines134 including C and from protonated theophylline with metallic
2- 2- 135 counteranions such as PtCl4 , PdBr4 have been reported. There are numerous reports which show the coordination of theophylline to silver(I) and other metal centers via N-
7136 with a few examples of coordination via N-9.137 A Ru(II)-NHC complex from protonated theophylline has also been reported.138 Ni(II), Co(II) and Pd(II) complexes of the acid form of C (theophylline-7-acetic acid) have been synthesized.139 In this chapter, we report the synthesis and characterization of the NHC silver(I) acetate complexes 2a,
2b and 2c from methylated A, B and C (1a, 1b and 1c) (Figure 4.2) and their antimicrobial activity against resistant respiratory pathogens.
O R O R H C H3C 3 N N O N N H X Ag O C CH3 N O N N O N CH3 CH3 CH3 CH3
- 1a: R= -CH2CH2OH, X= I 2a: R= -CH2CH2OH
- 1b: R=-CH2CHOHCH2OH, X= I 2b: R=-CH2CHOHCH2OH
- 1c: R=-CH2COOCH3, X= BPh4 2c: R=-CH2COOCH3
Figure 4.2 Methylated theophylline salts and silver(I) complexes
65 4.2 Results and Discussion
A and B were reacted with methyl iodide in a molar ratio of 1: ~7 in DMF under reflux conditions (Scheme 4.1). The resulting imidazolium salts, 1a and 1b, are water- soluble and air-stable solids. Formation of 2a and 2b were first confirmed by 1H NMR spectra of the salts. The imidazolium protons appeared at 9.34 and 9.32 ppm, respectively. In the 13C NMR, the imidazolium carbon atoms resonated at 139.4 and
139.5 ppm. These values are very close to the resonance of the imidazolium carbons of the methylated caffine.132,31
O R O R CH 3 CH3 N N N CH I N 3 H X DMF O N N O N N CH3 CH3 CH3
- - A: R= -CH2CH2OH, X= I 1a: R= -CH2CH2OH, X= I
- - B: R-CH2CHOHCH2OH, X= I 1b: R-CH2CHOHCH2OH, X= I
OH O O R O R CH CH CH3 3 O 3 N N 1.(CH3)2SO4 N N H SO N N 2 4 NO2 H X N O N N O N CH3OH N 2. NaBPh4 O N CH H2O 3 CH3 CH3 CH3
C: R= -CH2COOCH3 1c: R= -CH2COOCH3, X= BPh4
Scheme 4.1 Synthesis of 1a, 1b and 1c
66 C was synthesized through the acid catalyzed esterification of theophylline-7- acetic acid with methanol (Scheme 4.1).140 Methylation of C was tried with methyl iodide. However, even a reaction in a pressurized vessel for days gave only trace amount of the expected product. This can be explained by the decreased nucleophilicity of N-9 due to the presence of electron withdrawing ester group on the N-7. Therefore a stronger methylating agent, dimethyl sulfate, was used. Formation of several methylated imidazolium cations from -CH2CN, -CH2COC6H6, -CH2COC6H2Br4 substituted theophylline including C using methyl tosylate was also reported by Hori and coworkers.134 Methylation of C with dimethyl sulfate yielded a waxy solid which was became a white, water insoluble powder upon the addition of sodium tetraphenylborate to the water solution of the material (Scheme 4.1). The presence of the resonance at 9.31 ppm for the imidazolium proton and three resonances between ~7.20-6.75 ppm for the aromatic hydrogens in the 1HNMR spectrum were the most notable features indicating the formation of 1c. The imidazolium carbon appeared at 140.2 ppm in the 13C NMR spectrum.
Single crystals of 1a and 1b were obtained by slow evaporation of a concentrated methanol solution. The asymmetric units of 1a and 1b contain one methylated cation of each tehophylline derivatives and one iodide anion, respectively (Figure 4.3 and 4.4).
The colorless crystals of 1c were obtained from a concentrated sample in an acetonitrile/ water mixture (Figure 4.5). The asymmetric unit contains the methylated cation, tetraphenyl borate anion and one molecule of water. The selected N-C bond lengths and angles of 1a, 1b and 1c are similar.
67 Figure 4.3 Molecular structure of 1a. Thermal ellipsoids are drawn at 50% probability. Selected bond lengths (Å) and bond angles (°): N1-C1 = 1.351(4), N2-C1 = 1.322(5), N1- C1-N2 = 109.9(3).
Figure 4.4 Molecular structure of 1b. Thermal ellipsoids are drawn at 50% probability. Selected bond lengths (Å) and bond angles (°): N1-C4 = 1.322(7), N2-C4 = 1.340(7), N1- C4-N2 = 110.4(5).
68 Figure 4.5 Molecular structure of cationic part of 1c. Thermal ellipsoids are drawn at 50% probability. Selected bond lengths (Å) and bond angles (°): N1-C1 = 1.309(3), N2- C1 = 1.347(3), N1-C1-N2 = 110.7(2).
O O R R H3C N H3C N O N AgCO2CH3 N H X Ag O C CH3 CH3OH O N N O N N CH3 CH3 CH3 CH3
- 1a: R= -CH2CH2OH, X= I 2a: R= -CH2CH2OH - 1b: R=-CH2CHOHCH2OH, X= I 2b: R=-CH2CHOHCH2OH - 1c: R=-CH2COOCH3, X= BPh4 2c: R=-CH2COOCH3
Scheme 4.2 Synthesis of 2a, 2b and 2c
Silver(I) complexes, 2a and 2b, were synthesized through the deprotonation of 1a and 1b by silver(I) acetate in methanol in a molar ratio of 1:2 and 1.2:2, respectively
69 (Scheme 4.2). Similarly. the water insoluble imidazolium salt 1c was reacted with silver(I) acetate in acetonitrile in 1:2 ratio forming the complex 2c (Scheme 4.2). Loss of the imidazolium protons in the 1H NMR spectra and down field shifts of the imidazolium carbons to the carbene carbons at 187.3, 187.4 and 187.4 ppm in the 13C NMR spectra of
2a, 2b and 2c confirmed the formation of the expected silver(I) complexes. No 13C-107Ag and 13C-109Ag couplings were observed in the 13C NMR spectra of the three complexes.
Unlike the previously reported methylated caffeine silver(I) complexes which are already biscarbenes in the solid state31 and readily showed the same structure in the ESI-MS, complexes 2a, 2b and 2c were observed to rearrange in the gas phase and were detected as [NHC-Ag-NHC]+ by ESI- MS. This behavior was reported for many other silver(I)
NHC complexes of various motifs in the solid state.27,75,141 All three complexes are light stable solids with increased water solubility compared with the methylated caffeine analogue (11.6 mg/mL). Complexes 2a, 2b and 2c have the water solubility of 75.5 mg/mL, 82 mg/mL and 93 mg/mL, respectively. Based on the 1H NMR and 13C NMR studies, 2a and 2b were observed to decompose slowly in water in about same period of time (36 days, 39 days) on standing in the dark. The main decomposition product(s) could not be characterized but a small amount of imidazolium cations were able to be detected in 1H NMR spectra and the formation of the silver mirror was observed on surface of NMR tubes. Complex 2c was observed to decompose in 10 days on standing in the dark. Based on the 13C NMR and ESI-MS (sample let to decompose over 15 days and sodium chloride was added to precipitate Ag+), 2c was believed to decompose back to imidazolium cation.
70 Complexes 2a, 2b and 2c were characterized crystallographically. Single crystals of 2a were obtained by recrystalization in ethanol (Figure 4.6). The asymmetric unit contains two molecules of 2a with a weak Ag(I)….Ag(I) interaction of 3.3770(6) Å and one molecule of ethanol. Ag(I)- Ccarbene distances were found to be 2.061(3) Å and
2.060(3) Å, respectively. The geometry around the silver atom deviates significantly
o o from linearity with the Ccarbene-Ag- Oacetate angles of 164.65(11) and 163.85(11) . Single crystals of 2b and 2c were grown by slow evaporation of the solvents from the concentrated methanol and acetonitrile solutions, respectively (Figure 4.7 and 4.8).
Asymmetric units of 2b and 2c is composed of only one molecule of the respective silver(I) complexes. Ag(I)- Ccarbene bond lengths of 2.096(3) Å and 2.065(3) Å were observed for 2b and 2c, respectively (Table 4.1).
Figure 4.6 Molecular structure of 2a. Thermal ellipsoids are drawn at 50% probability. Hydrogen atoms were omitted and carbon atoms were not labeled for clarity.
71 Figure 4.7 Molecular structure of 2b.
Figure 4.8 Molecular structure of 2c.
72 Bond Lengths and Angles 2a 2b 2c
2.061(3) Å Ag-Ccarbene 2.096 Å 2.065(4) Å 2.060(3) Å
164.65(11)° Ag- Ccarbene- 171.44(9)° 176.88(14)° Oacetate 163.85(11)°
2.103(2) Å Ag-Oacetate 2.125(9) Å 2.115(3) Å 2.097(2) Å
Table 4.1 Selected bond lengths and angles of 2a, 2b and 2c
The in vitro antimicrobial activities of the silver complexes, 2a, 2b and 2c were evaluated against a variety of test organisms and a panel of highly resistant opportunistic pathogens recovered, primarily, from the respiratory tract of patients with cystic fibrosis
(CF) including members of the Burkholderia cepacia complex (Bcc). These studies were done by Lisa A. Hogue, Rebekah J. Mallett, Christine E. Hovis, Marvin Coughenour and
Carolyn L. Cannon in Washington University School of Medicine and listed in the tables
4.2, 4.3 and 4.4. All three complexes were found to show better antimicrobial activity than the methylated caffine silver(I) acetate complex. Using standard NCCLS broth microdilution methods, the MIC was found to range from 1 to 6 mg/mL for 2a, 1 to 8 mg/mL for 2b and 2c for the bacterial strains tested (Table 4.2, 4.3 and 4.4).
73 Table 4.2* Micro-dilution MIC testing of complex 2a
74 Table 4.3* Micro-dilution MIC testing of complex 2b
75 Table 4.4* Micro-dilution MIC testing of complex 2c
* Strains in Table 4.2, 4.3 and 4.4 kindly provided by aAmerican Type Culture Collection. bDr. Gerald Pier, Boston, MA. cDr. Thomas Ferkol, St. Louis, MO. dDr. John LiPuma, Ann Arbor, MI. eSt. Louis Children’s Hospital, Clinical Microbiology. fDr. Johannes Huebner, Boston, MA. gDr. Simon Silver, Chicago,IL.
76 Preliminary toxicity studies of 1a on a small number of rats showed that 1a, administered intravenously, has an approximate lethal dose (ALD) of 2100 mg/kg. The kidneys, livers, adrenals and hearts of the experimental rats appeared normal upon autopsy. ALD of 1b administered intraperitioneally was estimated to be 2250 mg/kg. The kidneys, livers, hearts and spleens appeared normal but the lungs were observed to be hemorrhagic upon autopsy. This could be because of a shock which causes a leakage in the capillaries of the lungs due to the high amount of 1b injected.
4.3 Conclusions
Three new NHC precursors from N-7 substituted theophyllines and their silver(I) acetate complexes were synthesized and showed better antimicrobial activity than the methylated caffeine analogue against highly resistant respiratory pathogens including members of the Burkholderia cepacia complex (Bcc). The presence of hydroxyl and ester groups on the imidazole moiety of the theophylline greatly enhanced the water solubility. Preliminary in vivo toxicity studies on the methylated ligands 1a and 1b showed that they are slightly less toxic than the methylated caffeine. In vivo toxicities of the silver complexes 2a, 2b and 2c have not been determined yet. Transcriptional and in vitro toxicity studies on murine tracheal epithelial cells are underway. Complex 2a, 2b and 2c may be potential candidates to be used as a nebulized therapy in CF patients colonized with resistant respiratory organisms.
77 4.4 Experimental
General Considerations
All manipulations were carried out in air. All compounds and solvents were used as received. 7-(2-hydroxyethy)theophylline and dimethyl sulfate were purchased form
Aldrich. 7-(2,3-dihydroxypropyl)theophylline, silver acetate and methyl iodide were purchased from Acros. Theophylline-7-acetic acid was purchased from Alfa Aesar. 1H
and 13C NMR data were recorded on a Gemini 300MHz instrument and were referenced
to residual protons and 13C signals of deuterated solvents. 109Ag NMR data was recorded on Unity Inova 750 MHz instrument and AgNO3 in d6- DMSO was used as an external
reference. Mass spectrometry data were collected on a Bruker Daltons (Billerica, MA)
Esquire-LC mass spectrometer equipped with ESI. Elemental analyses were performed
by University of Illinois Micro Analysis Laboratory. Crystal structure analysis of
compound 1a was done by Doug Medvetz. Antimicrobial studies were performed by
Lisa A. Hogue, Rebekah J. Mallett, Christine E. Hovis, Marvin Coughenour and Carolyn
L. Cannon, Division of Allergy and Pulmonary Medicine, Department of Pediatrics,
Washington University School of Medicine, St. Louis. ALD studies were done by
Khadijah Hindi in the biology department, The University of Akron.
Technical Details of the X-ray Structure Determinations
Crystals of 1a, 1b, 1c, 2a, 2b, and 2c were coated in paraffin oil, mounted on a
kryo loop and placed on a goniometer under a stream of nitrogen. X-ray crystallographic
data sets were collected on a Bruker Apex CCD diffractometer with graphite-
monochromated Mo KĮ radiation (Ȝ = 0.71073 Å). Unit cell determination was achieved
78 by using reflections from three different orientations. An empirical absorption correction and other corrections were done using multi-scan SADABS. Structure solution, refinement and modeling were accomplished using the Bruker SHELXTL package.108
The structure was obtained by full-matrix least-squares refinement of F2 and the selection of appropriate atoms from the generated difference map.
Synthesis of 7-(2-hydroxyethyl)-1,3,9-trimethylxanthinium iodide (1a)
Compound A (2.00 g, 8.92 mmol) was refluxed with methyl iodide (8.85 g, 62.3
mmol, 3.88 mL) in N, N’- dimethyl formamide (10 mL) at 150 oC for 22 hours. An excess amount of acetone was added to the resultant clear solution and the precipitate was filtered and washed with acetone. A white solid 1a (4.44 mmol, 1.62 g, 49.8 %) was
o obtained. Mp: 127-130 C. Anal. Calcd for C10H15 I N4O3: C, 32.80; H, 4.13; N, 15.30.
1 Found: C, 32.81; H, 4.04; N, 14.87. H NMR (300 MHz, d6-DMSO): į 9.34 (s, 1H,
NCHN), 5.22 (t, 1H, OH), 4.51 (t, 2H, CH2), 4.18 (s, 3H, NCH3), 3.75 (s, 5H, NCH2 and
13 1 NCH3 ), 3.28 (s, 3H, NCH3). C { H} NMR (75 MHz, d6-DMSO): į 153.1 (C=O),
150.0 (C=O), 139.4 (NCHN), 139.6 (C=C), 107.1 (C=C), 58.2 (CH2OH), 51.3 (NCH2),
+ 37.1, 31.5, 28.5 (NCH3). ESI-MS (m/z): [M ] calcd for C10H15 I N4O3, 239.1; found
239.1.
X-ray crystal structure analysis of 1a: formula C10H15 I N4O3, Mw = 366.16, colorless crystal 0.15 x 0.09 x 0.05 mm, a = 8.1744(12) Å, b = 12.8082(19) Å, c =
12.757(19) Å, Į = 90°, ȕ = 97.714(2)°, Ȗ = 90°, V = 1323.6(3) Å3, Dcalc = 1.548 Mg.m-3,
ȝ = 1.833 mm-1, Z = 4, monoclinic, space group P2(1)/c, Ȝ = 0.71073 Å, T = 100(2) K, Ȧ and ij scans, 11291 reflections collected, 3103 independent (Rint = 0.0257), 167 refined
79 parameters, R1/wR2 (I 2ı(I)) = 0.0389/ 0.0796 and R1/wR2 (all data) = 0.0433/ 0.0814, maximum (minimum) residual electron density 1.153(-0.963) e.Å-3.
Synthesis of 7-(2, 3-dihydroxypropyl)-1,3,9- trimethylxanthinium iodide (1b)
Compound B (5 g, 19.66 mmol) was refluxed with methyl iodide (8.8 mL, 20.06
g, 141.36 mmol) in DMF (20 mL) at 75- 77 oC for 5 hours. An excess amount of
acetone was added to the clear solution obtained to precipitate out the product . The
precipitate was filtered, washed with acetone and stirred in hot ethanol (70- 75oC) for 2- 3
hours. A white solid (9.97 mmol, 3.95 g, 50.7 %) was obtained. Mp: 163- 166oC. Anal.
Calcd for C11H17 I N4O4: C, 33.35; H, 4.33; N, 14.14. Found: C, 33.27; H, 4.18; N,
1 3 13.72. H NMR (300 MHz, d6-DMSO): į 9.32 (s, 1H, NCHN), 5.32 (d, 1H, OH, JHH =
3 2 5.1 Hz), 4.92 (t, 1H, OH, JHH = 5.7 Hz), 4.73 (d, H, NCH2A, JHH = 13.5 Hz ), 4.27 (d, H,
2 NCH2B, JHH = 13.5 Hz ), 4.18 (s, 3H, NCH3), 3.83 (m, 1H, CHOH), 3.74 (s, 3H, NCH3),
13 1 3.45(m, 2H, CH2OH), 3.27 (s, 3H, NCH3). C { H} NMR (75 MHz, d6-DMSO): į 153.2
(C=O), 150.1 (C=O), 139.7 (NCHN), 139.5 (C=C), 107.3 (C=C), 68.9 (CHOH), 63.5
1 13 (CH2OH), 51.9 (NCH2), 37.1, 31.5, 28.5 (NCH3). H- C NMR (Hetcor, 400 MHz,
D2O): 9.32-139.7, 4.73-52.0, 4.27- 52.0, 4.18- 37.1, 3.83- 68.9, 3.74- 31.5, 3.45- 63.5,
+ 3.27- 28.5. ESI-MS (m/z): [M ] calcd for C11H17I N4O4, 269.1; found 268.9.
X-ray crystal structure analysis of 1b: formula C11H17 I N4O4, Mw = 396.19, colorless crystal 0.26 x 0.23 x 0.07 mm, a = 7.6526(5) Å, b = 15.1108(9) Å, c =
24.4607(15) Å, Į = 90°, ȕ = 90°, Ȗ = 90°, V = 2828.6(3) Å3, Dcalc = 1.861 Mg.m-3, ȝ =
2.284 mm-1, Z = 8, orthorhombic, space group Pbca, Ȝ = 0.71073 Å, T = 100(2) K, Ȧ and
ij scans, 23382 reflections collected, 3426 independent (Rint = 0.0293), 186 refined
80 parameters, R1/wR2 (I 2ı(I)) = 0.0690/ 0.1291 and R1/wR2 (all data) = 0.0736/
0.01311, maximum (minimum) residual electron density 3.572(-1.296) e.Å-3.
Synthesis of 7-(methoxycarboxymethyl)-1,3-dimethylxanthine (C)
A mixture of theophylline-7-acetic acid (2.0 g, 8.39 mmol) and methanol (60.0
mL) containing concentrated sulfuric acid (~ 0.60 mL) was refluxed for 28 h. The clear
solution obtained was chilled to give white crystals of the product (1.18 g, 4.67 mmol, 56
o %). MP: 130-132 C. Anal. Calcd for C10H12O4N4: C, 47.62; H, 4.80; N, 22.21. Found:
1 C, 47.41; H, 4.80; N, 21.69. H NMR (300 MHz, d6-DMSO): į 8.06 (s, H, NCHN), 5.19
13 1 (s, 2H, NCH2), 3.70 (s, 3H, OCH3), 3.44 (s, 3H, NCH3), 3.20 (s, 3H, NCH3). C { H}
NMR (75 MHz, d6-DMSO): į 166.1 (C=O), 154.4 (C=O), 150.9 (C=O), 147.9 (C=C),
143.1 (NCHN), 106.3 (C=C), 52.5 (NCH2), 47.1 (OCH3), 29.5, 27.4 (CH3). ESI- MS
+ + (m/z): [M+H] calcd for C10H12N4O4 253.2, found 253.1. [M+Na] calcd for C10H12N4O4
275.2, found 275.1.
Synthesis of 7-(methoxycarboxymethyl)-1,3,9-trimethylxanthinium tetraphenylborate (1c)
Compound C (0.66 g, 2.63 mmol) was refluxed with dimethyl sulfate (0.5 mL,
5.26 mmol) in nitrobenzene (18 mL) at 130-140 oC for 5 h. Volatiles were removed in vacuo and the waxy brownish solid was dissolved in water. Sodium tetraphenyl borate
(0.90 g, 2.63 mmol) was added to give a white precipitate. The precipitate was filtered, washed with water and diethyl ether. White crystals of the product were obtained by layering the concentrated acetonitrile solution with water (1.27 g, 2.16 mmol, 82%). MP:
81 o 210- 212 C. Anal. Calcd for C35H35BN4O4: C, 71.68; H, 6.02; N, 9.55. Found: C, 70.69;
1 H, 5.91; N, 9.66. H NMR (300 MHz, d6-DMSO): į 9.31 (s, H, NCHN), 7.17 (d, 2H,
C6H5), 6.89 (t, 2H, C6H5), 6.78 (t, 1H, C6H5), 5.46 (s, 2H, NCH2), 4.21 (s, 3H, NCH3),
13 1 3.77 (s, 3H, OCH3), 3.75 (s, 3H, NCH3), 3.25 (s, 3H, NCH3). C { H} NMR (75 MHz, d6-DMSO): į 166.5 (C=O), 153.2 (C=O), 150.2 (C=O), 140.2 (NCHN), 139.4 (C=C,
C6H5), 135.6 (C=C, C6H5), 125.5 (C=C, C6H5), 121.7 (C=C, C6H5), 107.3 (C=C), 53.1
(NCH2), 49.2 (OCH3), 37.2, 31.4, 28.5 (CH3). ESI- MS (m/z): [M+] calcd for
- C35H35N4O4B 267.1, found 267.0. [M ] calcd for C35H37N4OB 319.2, found 319.1.
X-ray crystal structure analysis of 1c (cocrystallized with H2O): formula
C35H37BN4O5, Mw = 602.48, colorless crystal 0.43 x 0.16 x 0.11 mm, a = 15.9058(18)
Å, b = 18.200(2) Å, c = 21.116(3) Å, Į = 90°, ȕ = 90°, Ȗ = 90°, V = 6112.8(12) Å3, Dcalc
= 1.309 Mg.m-3, ȝ = 0.088 mm-1, Z = 8, orthorhombic, space group Pbca, Ȝ = 0.71073 Å,
T = 100(2) K, Ȧ and ij scans, 49968 reflections collected, 7330 independent (Rint =
0.0902), 410 refined parameters, R1/wR2 (I 2ı(I)) = 0.0704/ 0.1483 and R1/wR2 (all data) = 0.1403/ 0.1761, maximum (minimum) residual electron density 0.361(-0.558) e.Å-3.
Synthesis of (7-(2-hydroxyethyl)-1,3,9-trimethylxanthine-8-ylidene)silver(I) acetate (2a)
Compound 1a (7.34 mmol, 2.69 g) was dissolved in methanol (184 mL) and silver acetate (14.7 mmol, 2.45 g) added. The mixture was stirred at room temperature for 2 h.
The yellow silver iodide suspension was filtered to give a colorless solution. The volatiles were removed in vacuo. Compound 2a (2.37 mmol, 0.96 g, 32 %) was obtained as a white solid after recrystallization in ethanol. Mp: 174-177oC. Anal. Calcd for
82 1 C12H17AgN4O5: C, 35.57; H, 4.23; N, 13.83. Found: C, 35.66; H, 4.41; N, 12.87. H
NMR (300 MHz, D2O): į 4.95 (s, 1H, OH), 4.46 (t, 2H, CH2), 4.17 (s, 3H, NCH3), 3.75
13 1 (s, 5H, CH3 and NCH2), 3.24 (s, 3H, NCH3), 1.80 (s, 3H, COOCH3). C { H} NMR (75
MHz, DMSO):į 187.3 (C-Ag), 173.6 (C=O), 153.4 (C=O), 150.7 (C=O), 140.9 (C=C),
109 108.4 (C=C), 60.3 (CH2), 53.3 (NCH2), 39.2, 31.8, 28.5 (NCH3), 23.1 (COOCH3). Ag
+ + NMR: 276.15 (sharp). ESI-MS (m/z): 583.2 [C20H18AgN8O6 ], 345.0 [C10H14AgN4O3 ],
+ 239.1 [C10H15N4O3 ].
X-ray crystal structure analysis of 2a (with C2H6O cocrystallized): formula
C26H40N8O11Ag2, Mw= 856.39, colorless crystal 0.64 x 0.43 x 0.18 mm, a =
8.5766(11)Å, b = 12.5430(16) Å, c = 15.621(2) Å, Į = 104.634(2)° ȕ = 97.056(2)°, Ȗ =
95.866(2)°, V = 1598.0(4) Å3, Dcalc = 1.780 Mg.m-3,ȝ = 1.296 mm-1, Z = 4, triclinic, space group P-1, Ȝ = 0.71073Å, T = 100 K, Ȧ and ij scans, 14268 reflections collected,
7389 independent (Rint = 0.0307), 436 refined parameters, R1/wR2 (I 2ı(I)) = 0.0399/
0.0879 and R1/wR2 (all data) = 0.0506/ 0.0922, maximum (minimum) residual electron density 0.998(-0.798) e.Å-3.
Synthesis of (7-(2,3-dihydroxypropyl)-1,3,9-trimethylxanthine-8-ylidine)silver(I) acetate
(2b)
Compound 1b (0.73 mmol, 0.29 g) was dissolved in methanol (5 mL) and silver acetate (1.22 mmol, 0.20 g) added. The mixture was stirred at 60oC for 2 h. under refluxing conditions. The yellow silver iodide suspension was filtered to give a colorless solution. The volatiles were removed in vacuo. Compound 2b (0.32 mmol, 0.14 g, 44 %) was obtained as a white solid after washing the crude product with hot ethanol (70oC-
83 o o 75 C). Mp: 167-170 C. Anal. Calcd for C13H19AgN4O6: C, 35.88; H, 4.40; N, 12.87.
1 Found: C, 35.84; H, 4.36; N, 12.52. H NMR (400 MHz, d6-DMSO): 5.06 (broad s, 1H,
2 OH), 4.88 (broad s, 1H, OH), 4.51 (d, 1H, NCH2A, JHH = 13.2 Hz ), 4.31 (d, 1H, NCH2B,
2 JHH = 13.2 Hz ), 4.28 (s, 3H, NCH3), 3.83 (m, 1H, CHOH), 3.74 (s, 3H, NCH3), 3.41(m,
13 1 2H, CH2OH), 3.24 (s, 3H, NCH3), 1.80 (s, 3H, COOCH3). C { H} NMR (75 MHz, d6-
DMSO): į 187.4 (C-Ag), 174.1 (C=O), 153.3 (C=O), 150.6 (C=O), 140.7 (C=C), 108.7
(C=C), 70.74 (CH2OH), 63.5 (CHOH), 53.8 (NCH2), 39.5 (NCH3, under DMSO peak),
1 13 31.7, 28.4 (NCH3), 23.0 (COOCH3). H- CNMR (Hetcor, 400 MHz, d6-DMSO): 4.68-
54.0, 4.30- 54.0, 3.90- 69.0, 3.55- 65.9, 4.25- 38.0, 3.72- 31.7, 3.27- 29.2, 1.78- 24.0.
109 + Ag NMR (750 MHz, D2O): 324.109 (broad). ESI-MS (m/z): 645.0, [C22H32AgN8O8 ];
+ + 378.8, [C11H16AgN4O4 ]; 268.9, [C11H17N4O4 ].
X-ray crystal structure analysis of 2b: formula C13H19AgN4O6, Mw= 435.19, colorless crystal 0.34 x 0.34 x 0.22 mm, a = 8.9319(10) Å, b = 9.0361(10) Å, c =
10.9601(13) Å, Į = 90.103(2)° ȕ = 101.168(2)°, Ȗ = 114.159(2)°, V = 788.57(16) Å3,
Dcalc = 1.833 Mg.m-3,ȝ = 1.318 mm-1, Z = 2, triclinic, space group P-1, Ȝ = 0.71073Å, T
= 100 K, Ȧ and ij scans, 6767 reflections collected, 3539 independent (Rint = 0.0174), 223 refined parameters, R1/wR2 (I 2ı(I)) = 0.0298/ 0.0745 and R1/wR2 (all data) = 0.0309/
0.0753, maximum (minimum) residual electron density 1.686(-0.421) e.Å-3.
Synthesis of (7- methoxycarboxymethyl)-1, 3, 9- trimethylxanthine- 8- ylidene)silver(I)acetate (2c)
Compound 1c (1.42 g, 2.42 mmol) was dissolved in acetonitrile (120 mL) and silver acetate (0.80 g, 4.84 mmol) was added. The mixture was stirred at room
84 temperature for 2.5 h and filtered to a clear solution. The volume of the solution was reduced in vacuo and diethyl ether was added to precipitate a beige solid. The solid was filtered and stirred in diethyl ether yielding the product (0.76 g, 1.75 mmol, 73 %). MP:
o 204- 206 C. Anal. Calcd for C13H17O6N4Ag: C, 36.06; H, 3.84; N, 12.60. Found: C,
1 36.05; H, 3.96; N, 12.93. H NMR (300 MHz, d6-DMSO): į 5.31 (s, 2H, NCH2), 4.20 (s,
3H, NCH3), 3.75 (s, 3H, OCH3), 3.71 (s, 3H, NCH3), 3.21 (s, 3H, NCH3), 1.79 (s, 3H,
13 1 COOCH3). C { H} NMR (75 MHz, d6-DMSO): į 187.4 (C-Ag), 175.7 (C=O), 168.1
(C=O), 153.1 (C=O), 150.4 (C=O), 140.4 (C=C), 108.6 (C=C), 52.5 (NCH2), 51.4
(OCH3), 38.9, 31.5, 28.2 (NCH3), 23.4 (COOCH3). ESI- MS (m/z): 641.2
+ + + [C22H28AgN8O8] , 391.1 [C11H16AgN4O4+H2O] , 373.1 [C11H16AgN4O4] .
X-ray crystal structure analysis of 2c: formula C13H15AgN4O6, Mw= 433.18, colorless crystal 0.46 x 0.06 x 0.05 mm, a = 4.8968(9) Å, b = 10.5734(18) Å, c =
15.016(3) Å, Į = 100.474(3)° ȕ = 92.729(3)°, Ȗ = 98.084(3)°, V = 754.8(2) Å3, Dcalc =
1.906 Mg.m-3,ȝ = 1.376 mm-1, Z = 2, triclinic, space group P-1, Ȝ = 0.71073Å, T = 100 K,
Ȧ and ij scans, 6612 reflections collected, 3482 independent (Rint = 0.0255), 222 refined parameters, R1/wR2 (I 2ı(I)) = 0.0424/ 0.1013 and R1/wR2 (all data) = 0.0452/ 0.1038, maximum (minimum) residual electron density 2.079(-1.117) e.Å-3.
In vitro antimicrobial activity
The micro-broth dilution MIC determination was performed using a standard
NCCLS protocol.76,125 Bacteria are streaked from glycerol-frozen stocks onto blood agar plates and incubated overnight at 37°C. Cells from the fresh plates are suspended in either Luria broth or the NCCLS standard Mueller-Hinton broth to an OD650 of 0.25 and
85 8 grown in a shaking incubator until the OD650 is 0.4, which corresponds to ~2 x 10
CFU/mL, confirmed by plating serial dilutions. The bacteria are diluted in broth to a concentration corresponding to 105 CFU in 100 mL, which is added to triplicate well of a
96 well plate containing 100 mL of the complexes 2a, 2b and 2c concentration to be tested. The plate is incubated for 18 hours at 37°C and MIC determined as the lowest concentration with clear wells.
Animal Studies
Male Sprague Dawley (Harlan Sprague Dawley, Indianapolis, IN) adult rats (300 g average body weight) were housed in the University of Akron animal facility.
Temperature and humidity were held constant, and a standard light cycle (12 hours light/12 hours dark) was used. Food (Lab diet 5P00, Prolab, PMI nutrition, Intl.,
Bretwood, MO) and water were provided ad libitim. Animals were anesthetized with ether to inject the compound 1a into the tail vein, using a 26 3/8 gauge syringe needle in a volume of 0.3 mL sterile saline. The concentrations of the ligand ranged from 1000 mg/kg to 2200 mg/kg. Compound 1b injected intraperitioneally using a 26 3/8 gauge syringe needle in a volume of 1 mL sterile saline. The concentrations of the ligand depending on the weight of the individual rat ranged from 2000 mg/kg to 2500 mg/kg.
At the end dosages of the experiment, animals were terminated, and the liver, lung, kidney, and heart tissues were removed and frozen at -70 °C for 24 hours. Urine samples were collected using metabolic cages for later examination of the compound distribution.
86 CHAPTER V
SYNTHESIS AND CHARACTERIZATION OF N-HETEROCYCLIC CARBENE
RHODIUM(I), PLATINUM(II) AND PALLADIUM(II) COMPLEXES FROM
CAFFEINE
5.1 Introduction
The dynamic behavior characterized by the lack of C-107Ag and C-109Ag couplings in the 13CNMR of silver(I) NHC complexes of methylated caffeine makes them valuable candidates to be used as carbene transfer reagents. Carbene transfer from silver(I) NHC complexes to other transition metals provides mild reaction conditions without the use of a base and have become very popular142,29 after the synthesis of palladium(II) and gold(I) NHC complexes by Lin and coworkers.26
There are a relatively small number of NHC transition metal complexes of caffeine. Ru(II), Ru(III) and Os(III) complexes of protonated caffeine and a bis(NHC)
Hg(II) complex of methylated caffeine were the only NHC metal complexes known until
2004.143,144,145,146 After the synthesis of the first Rh(I) NHC complex of methylated caffeine31 by our group, other Rh(I) complexes containing two and four methylated caffeine units and Ir(I), Pd(II) complexes were reported.99,147,148
There have been several reports of the synthesis of Pd(II) NHC complexes using
87 palladium(II) acetate .149,150,151,152 However, Pt(II) NHC complexes are not attainable by this method. Recently, the use of platinum(II) halides in the presence of sodium acetate152,153 and the use of platinum(II) acetylacetonate154 as a commercially available basic metal precursor have made Pt(II) NHC complexes readily available. In this chapter, we report the synthesis of the first Rh(I), Pt(II) mono(NHC) complexes, 1 and 2, and
bis(NHC) Pd(II), 3, complex from methylated caffeine (Figure 5.1).
O + O CH3 CH3 H3C N H3C N N N N O O N Cl N PF6 N Rh CH3 Pt CH CH3 CH3 3 Cl SOC2H6 SOC2H6
1 2
O CH3 H3C O CH3 I CH3 N N N N Pd O N N N N O I CH H C CH3 3 3 CH3
3
Figure 5.1 Rh(I), Pt(II) and Pd(II) complexes of methylated caffeine
5.2 Results and Discussion
The bis(NHC)AgPF6, B, complex was synthesized from methylated caffeine
hexafluorophosphate, A, and silver(I) oxide as described in chapter II. This complex is a
88 light stable solid and only soluble in DMSO. The lack of C-107Ag and C-109Ag couplings in the 13CNMR spectrum suggests fluxional behavior in solution. The reaction of
o equimolar amounts of complex B and [Rh(COD)Cl]2 in wet DMSO at 60 C to give the corresponding Rh(I) complex, 1, shows the ability of B to serve as a carbene transfer reagent (Scheme 5.1). Complex 1 is stable in air up to its melting point and is soluble in acetone and DMSO. It was observed to be stable in wet DMSO in light for months. In
13 1 the C NMR spectrum, the carbene carbon appears as a doublet at 188.46 ppm ( JC-Rh=
43.8 Hz) (Figure 5.2) . The chemical shift of the carbene carbon and coupling constant are similar to those previously reported for other NHC rhodium complexes.155,156,157
+ O CH3 + O CH3 H3C O H3C N CH3 H3C N N N O N N [Rh(COD)Cl]2 N Ag PF6 N PF6 Rh O N N N N CH3 O DMSO CH3 CH SOC2H6 CH3 3 H3C CH3
B 1
Scheme 5.1 Synthesis of 1 by carbene transfer from B
89 + O CH3 H3C N N O N - N PF6 Rh CH3 CH3 SOC2H6
JRh-C = 43 Hz
Figure 5.2 13C NMR of complex 1
Deprotonation of A with sodium acetate (1:1.2 molar ratio) in wet DMSO at 90 oC
1 in the presence of PtCl2 produced complex 2 (Scheme 5.2). H NMR spectrum of 2 in d6-
DMSO revealed that the characteristic signal for the acidic proton in the imidazolium salt at 9.25 ppm for A disappeared. Furthermore the 13C NMR spectrum showed a significant shift for the carbonium atom at the carbenic carbon at 175.4 ppm. The chemical shift of the carbene carbon is comparable to those previously reported for other mono NHC platinum complexes.158 No 195Pt-13C coupling was distinguishable in the 13C NMR.
90 O CH3 H C 3 N O CH3 N CH3 O Cl N N N NaOAc N PF6 + PtCl2 Pt CH DMSO CH3 3 O N N Cl SOC2H6 CH CH3 3 2 A
Scheme 5.2 Synthesis of 2
Crystals of 1 suitable for single crystal X-ray diffraction studies were grown from a concentrated solution of acetone and cyclohexane (Figure 5.3). The following explanation for the crystal structure of 1 was written by Matthew Panzner. The asymmetric unit contains two Rh(I) NHC complexes in different conformations and two hexafluorophospahte anions. Each Rh(I) center is bound to a methylated caffeine,
DMSO and cyclooctadiene in a square planar fashion. The two Rh(I) NHC bonds are
2.034(3) Å and 2.035(3) Å, respectively, and are comparable with those found in other
NHC Rh complexes. 147,159,160 The bond angles about the Rh centers deviate slightly from
90o ranging from 86.1-93.0° with an average of 90.1°(Figure 5.3). The greatest deviation is associated with the COD-Rh-COD bond angle most likely due to the bidentate nature of the COD. Deviations for other substituents are likely a result of the space created by the acute angle of the COD-Rh-COD bond angle.
91 Figure 5.3 Molecular structure of the cationic part of 1. Hydrogen atoms have been omitted for clarity. Selected bond lengths (Å) and bond angles (°): Rh1-C1 = 2.034(3), Rh1-S1 = 2.2742(9), N1-C1 = 1.383(4), N2-C1 = 1.335(4), C1-Rh1-S1 = 91.75(9), C1- Rh1-C10 = 90.00(13), C1-Rh1-C11 = 91.96(13), S1-Rh1-C15 = 93.52, S1-Rh1-C14 = 88.43(10).
Complex 2 is soluble in polar solvents such as acetonitrile, acetone and DMSO.
Colorless crystals of 2 were grown from a concentrated sample in an acetonitrile/ ethanol
mixture (Figure 5.4). 2 is a neutral complex with two coordinating chlorides balancing
the charge of the metal. The platinum(II) center is bound in a square planar fashion to
methylated caffeine, two chlorides in cis configuration and one DMSO molecule. Pt-
152,153,161 Ccarbene bond length is 1.922(8) Å and comparable with other Pt NHC complexes.
The platinum chloride distance trans to NHC, Pt-Cl(2), is longer than the one trans to
DMSO, Pt-Cl(1), due to the trans influence of NHC ligand by its strong ı donor ability.
The bond angles about Pt center deviate slightly from 90o ranging from 87.4- 91.4°
(Figure 5.4).
92 Figure 5.4 Molecular structure of 2. Hydrogen atoms have been omitted for clarity. Selected bond lengths (Å) and bond angles (°): Pt-C1 = 1.922(8), Pt-Cl(1) = 2.284(2), Pt- Cl(2) = 2.298(2), Pt-S = 2.167(2), N1-C1 = 1.332(7), N1A-C1 = 1.332(7), S-Pt-C1 = 91.4(2), C1-Pt-Cl(1) = 87.4(2), Cl(2)-Pt-Cl(1) = 91.28(8), Cl(2)-Pt-S = 89.97(8).
The reaction of 2:1 molar amounts of iodide salt of the methylated caffeine, C,
and palladium(II) acetate in wet DMSO at 80-90 oC produced complex 3 (Scheme 5.3). 3 is an air stable, yellow powder. It is not soluble in common organic solvents but
CH3 O O CH3 H3C O CH3 CH I CH N Pd(OAc) 3 3 N 2 N N N N I Pd O N DMSO N O N N N N O CH I CH3 3 CH H C CH3 3 3 CH3
C 3
Scheme 5.3 Synthesis of 3
93 is soluble in DMF and DMSO. Disappearance of the imidazolium proton in the 1H NMR spectrum and the appearance of the carbene carbon resonance at 174 ppm in 13C NMR were the most notable features indicating the formation of 3 (Figure 5.5). Single crystals of 3 suitable for X-ray studies could not be obtained. However, the resonance of the carbene carbon at 174.0 ppm was an indication for the trans configuration of the NHC ligands around Pd(II) center. In the literature, the chemical shift for the carbene carbon of trans- NHC Pd complexes have been reported to be observed between 175-186 ppm in 13C NMR spectra.162,163 Raman spectrum of complex 3 showed only one Pd-I stretching band at a very low frequency, 139 cm-1 which is characteristic for trans- configuration of the palladium iodide bonds in square planar geometry.164,165,166 ESI-MS analysis showed the molecular cations, [M-I]+, [M-2I]+ ([M-2I] +2 + 1 electron) by m/z peaks at 648.1 and 522.1, respectively.
94 O c O CH3 H3C h H C i I i CH 3 d N N 3 N N a Pd g O N e N I N N O b f CH3 H3C CH3 CH3
h f
a g i d e c
Figure 5.5 13C NMR of 3
5.3 Conclusions
We have synthesized three new NHC-late transition metal complexes of methylated caffeine. The formation of an NHC rhodium(I) complex, 1, from previously synthesized bis(NHC) silver(I) complex, B demonstrates the ability of B to serve as a carbene transfer reagent in mild reaction conditions without the use of strong bases.
Similarly, Pt(II) and Pd(II) complexes, 2 and 3, are shown to be synthesized from easily available metal precursors in air using a conventional solvent.
95 5.4 Experimental
General Considerations
All manipulations were carried out in air. [Rh(COD)Cl]2 (COD=
cyclooctadiene), PtCl2 and Pd(OAc)2 were purchased from Strem and used without
further purification. Caffeine was purchased from Acros and used without further
purification. 1H and 13C NMR data were recorded on a Gemini 300 MHz instrument and
referenced to residual protons and 13C signals of deuterated solvents. Mass spectrometry
data were collected on a Bruker Daltons (Billerica, MA) Esquire-LC mass spectrometer
equipped with ESI. Raman spectrum in the 10-3500 cm-1 region of the solid material was
measured using a Jobin Yvon T64000 triple-monochromator with the excitation line Ȝ=
647.1 nm of a Krypton-ion Laser in the Department of Polymer Science, The University of Akron. Crystal structure analyses were done by Matthew Panzner and Jered C.
Garrison. Elemental analyses were performed by University of Illinois Micro Analysis
Laboratory.
Technical Details of the X-ray Structure Determinations
Crystal of 1 and 2 were coated in paraffin oil, mounted on a kryo loop and placed on a goniometer under a stream of nitrogen. X-ray data sets were collected on a Bruker
Apex CCD diffractometer with graphite-monochromated Mo KĮ radiation (Ȝ = 0.71073
Å). Unit cell determination was achieved by using reflections from three different orientations. An empirical absorption correction and other corrections were done using multi-scan SADABS. Structure solution, refinement and modeling were accomplished using the Bruker SHELXTL package.108 The structure was obtained by full-matrix least-
96 squares refinement of F2 and the selection of appropriate atoms from the generated
difference map.
Synthesis of NHC Rh(I) complex (1)
Complex B (0.67 g, 1.0 mmol) was dissolved in DMSO (40 ml) and
o [Rh(COD)Cl]2 (0.50 g, 1.0 mmol) added. The mixture was stirred at 60 C for 1 h to
form a suspension. After filtration a clear, brick red solution was obtained. The solvent
was removed in vacuo to yield 1 (0.63 g, 0.98 mmol, 99%). Mp: 157 oC. 1H NMR (300
MHz, d6-DMSO):į 4.23 (s, CH3), 3.72 (s, CH3), 3.50 (s, CH3), 3.22 (s, CH3), 2.50 (m,
6H, C2H6OS), 4.93 (m, 2H, CH(COD)), 4.44 (m, 2H, CH(COD)), 2.28 (m, 4H, CH2(COD)),
13 1 1 1.96 (m, 4H, CH2(COD)). C { H} NMR (75 MHz, d6-DMSO):į 188.4 (d, C-Rh, JRh-C=
1 43.8 Hz), 152.3 (C=O), 150.0 (C=O), 141.0 (C=C), 110.0 (C=C), 98.3 (CH(COD), JCH-Rh=
1 7.35 Hz), 97.8 (CH(COD), JCH-Rh= 7.35 Hz), 40.4, 37.1, 30.0, 27.9 (N-CH3), 30.6
+ (CH2(COD)), 29.0 (CH2(COD)). ESI-MS (m/z): [M ] calcd for C19H30RhF6N4O3PS, 419.0; found 419.1.
X-ray crystal structure analysis of 1: formula C19H30F6N4O3PRhS, Mw = 642.41, colorless crystal 0.16 x 0.11 x 0.07 mm, a = 12.4032(17) Å, b = 14.879(2) Å, c =
15.685(2) Å, Į = 81.515(2)°, ȕ = 68.783(2)°, Ȗ = 74.762(2)°, V = 2599.2(6) Å3, Dcalc =
1.642 Mg cm-3, ȝ = 0.870 mm-1, Z = 4, triclinic, space group P-1 (No. 2), Ȝ = 0.71073Å, T
= 100 K, Ȧ and ij scans, 18806 reflections collected, 9123 independent (Rint = 0.0327),
872 refined parameters, R1/wR2 (I 2ı(I)) = 0.0364 / 0.0909 and R1/wR2 (all data) =
0.0452 / 0.0940, maximum (minimum) residual electron density 0.955 (-0.902) e Å-3, hydrogen atoms were found from the difference map and their positions refined.
97 Synthesis of NHC Pt(II) complex (2)
A (0.80 g, 2.26 mmol) was dissolved in DMSO (55.0 ml), sodium acetate (0.37 g,
2.72 mmol) and PtCl2 (0.60 g, 2.26 mmol) were added. The mixture was stirred at 80-
90oC for 3 h. The solvent was removed in vacuo and the solid obtained dissolved in acetone. The white precipitate of excess sodium acetate was filtered and acetone removed. The white, sticky solid was stirred in ethanol until it turned to a fine powder
(1.04 g, 1.66 mmol, 73 %). MP: 252- 254 oC. Anal. Calcd for
. C11H18PtN4O3SCl2 DMSO: C, 24.77; H, 3.84; N, 8.89. Found: C, 24.81; H, 3.86; N,
1 8.23. H NMR (300 MHz, d6-DMSO): į 4.40 (s, 3H, CH3), 4.19 (s, 3H, CH3), 3.74 (s,
13 1 3H, CH3), 3.22 (s, 3H, CH3), 2.54 (s,6H, CH3). C { H} NMR (75 MHz, d6-DMSO): į
175.4 (C-Pt), 153.0 (C=O), 150.3 (C=O), 139.7 (C=C), 108.4 (C=C), 40.4, 36.4, 31.6,
+ 28.2 (CH3). ESI- MS (m/z): 575.0 [C11H18PtN4O3SCl2]Na .
X-ray crystal structure analysis of 2: formula C11H18N4O3PtSCl2, Mw = 552.34, colorless crystal 0.14 x 0.06 x 0.04 mm, a = 7.732(2) Å, b = 8.645(2) Å, c = 11.701(3) Å,
Į = 90°, ȕ = 102.142(4)°, Ȗ = 90°, V = 764.6(3) Å3, Dcalc = 2.399 Mg cm-3, ȝ = 9.678 mm-1, Z = 2, monoclinic, space group P2(1)/m, Ȝ = 0.71073Å, T = 100 K, Ȧ and ij scans,
6681 reflections collected, 1966 independent (Rint = 0.0445), 127 refined parameters,
R1/wR2 (I 2ı(I)) = 0.0361 / 0.0765 and R1/wR2 (all data) = 0.0500/ 0.0818, maximum
(minimum) residual electron density 2.507 (-1.257) e Å-3, hydrogen atoms were found from the difference map and their positions refined.
98 Synthesis of NHC Pd(II) complex (3)
C (2.50 g, 7.44 mmol) was dissolved in DMSO (60 ml) and Pd(OAc)2 (0.84 g,
3.72 mmol) was added. The mixture was stirred at 80oC-90 oC for 20 h. The yellow precipitate formed was filtered and stirred in diethyl ether to give a fine powder (1.16 g,
o 1.49 mmol, 40%). MP: 357-360 C. Anal. Calcd for C18H24I2N8O4Pd: C, 27.30; H, 2.84;
1 N, 13.51. Found: C, 27.81; H, 3.09; N, 14.42. H NMR (300 MHz, d6-DMSO): į 4.30
13 1 (s, 3H, CH3), 4.11 (s, 3H, CH3), 3.74 (s, 3H, CH3), 3.22 (s, 3H, CH3). C { H} NMR (75
MHz, d6-DMSO): į 174.0 (C-Pd), 152.8 (C=O), 150.2 (C=O), 140.4 (C=C), 109.3
+ + (C=C), 36.8, 31.4, 28.1 (CH3). ESI- MS (m/z): 648.1 [M-I] , 522.1 [M-2I] . Raman
(cm-1): 1706, 1664, 1536, 1431, 1398, 1324, 1255, 1098, 1046, 923, 571, 139.7.
99 CHAPTER VI
CONCLUSION
The presence of imidazole moieties in the structures of some biologically relevant molecules, such as xanthines, provides the opportunity for the synthesis of new NHC ligands. Thus far, there are only a handful of examples for the formation of NHC metal complexes from these ligands in the literature. Caffeine and theophylline derivatives are readily available, inexpensive methyl xanthines.
In this study, formation of different imidazolium salts of methylated caffeine with
- - - - CH 3SO 4 , PF6 , I and NO3 were first explored. The relatively easy synthesis of these salts made them very useful NHC precursors. The bis(NHC) silver(I) complexes 2a, 2b
(chapter II) and 3 (chapter III) and a dinuclear silver(I) bis(NHC) complex 2d (chapter II) were synthesized utilizing silver(I) oxide as a metal precursor. Free NHCs are water sensitive however complex 2a was successfully synthesized in water. Therefore, the deprotonation of the imidazolium salt and concerted coordination to the metal center were suggested. Complex 3 was observed to form with a methyl carbonate anion through the silver(I) oxide promoted reaction of methanol and carbon dioxide from air. The Ag-C bond lengths and angles around the Ag centers of 2b and 3 were observed to be comparable. However, complex 2d showed distorted trigonal planar geometry due to the
100 bridging nitrates. Formation of silver(I) NHC complexes with bridging nitrates are known to be rare.18,107
The lack of 107/109Ag-13C couplings in the 13C NMR spectra of these complexes suggested dynamic behavior in solution. Therefore, the carbene moiety in the complex
2b was successfully transferred to rhodium(I) providing an NHC rhodium(I) complex from methylated caffeine. Pt(II) and Pd(II) complexes were also synthesized from readily available metal precursors. In the crystal structure of Pt(II) complex, one of the most notable feature was the bond length differences in Pt-Cl bonds. The Pt-Cl bond trans to the methylated caffeine unit was observed to be longer than the one trans to the
coordinated solvent molecule. This could be explained by the stronger ı donor ability of
NHC ligand compared to solvent molecule.
Iodide salts of the methylated caffeine and other theophylline derivatives were
deprotonated with silver(I) acetate to synthesize mixed NHC silver(I) acetate complexes.
The presence of hydroxyl and ester groups on the imidazole moiety of the theophylline
derivatives 2a, 2b and 2c (chapter IV) greatly increased the water solubility compared to methylated caffeine silver(I) acetate complex, 4 (chapter II). These complexes showed fluxional behavior in 13C NMR time scale, and therefore they can be potentially used as carbene transfer reagents.
All of the synthesized NHC acetate complexes of silver from xanthines showed very promising antimicrobial activities against resistant respiratory pathogens including members of the multi drug resistance Burkholderia cepacia complex seen in cystic fibrosis patients. Because these complexes are composed of biologically relevant ligands, their relatively small size, water solubility and stability make them very
101 attractive complexes to be used as a nebulized therapy in the treatment of patients colonized with resistant bacteria and fungi.
102 REFERENCES
1 Wanzlick, H. –W.; Kleiner, H. –J. Angew. Chem. 1961, 73, 493.
2 Wanzlick, H. –W.; Angew. Chem. Int. Ed. Engl. 1962, 1, 75.
3 Wanzlick, H. –W.; Esser, F.; Kleiner, H. –J. Chem. Ber. 1963, 96, 1208.
4 K. J. Öfele, K. J. Organomet. Chem. 1968, 12, 42.
5 Wanzlick, H.-W.; Schönherr, H.-J. Angew. Chem. Int. Ed. Engl. 1968, 7, 141.
6 Lappert, M. F. J. Organomet. Chem. 1975, 100, 139.
7 Hitchcock, P. B.; Lappert, M. F. J. Organomet. Chem. 1982, 239, C26.
8 Lappert, M. F. J. Organomet. Chem. 1988, 358, 185.
9 Arduengo, A. J. III; Harlow, R. L.; Kline, M. J. Am. Chem. Soc. 1991, 113, 361.
10 a.Herrmann, W. A. Angew. Chem., Int. Ed. Engl. 2002, 41, 1290. b. Peris, E.; Crabtree, R. H. Coord. Chem. Rev. 2004, 248, 2239. c. Nanchen, S.; Pfaltz, A. Chemistry-Eur. J. 2006, 12, 4550. d. Lillo, V.; Mata, J.; Ramirez, J.; Peris, E.; Fernandez, E. Organometallics 2006, 25, 5829. e. Crudden, C. M.; Allen, D. P. Coord. Chem. Rev. 2004, 248, 2247.
11 Herrmann, W. A.; Angew. Chem., Int. Ed. Engl. 1997, 36, 2162.
12 Bourissou, D.; Guerret, O.; Gabbaï, F. P.; Bertrand, G.; Chem. Rev. 2000, 100, 39.
13 Lai, C-L.; Guo, W-H.; Lee, M-T.; Hu, C-H. J. Organomet. Chem. 2005, 690, 5867.
14 Nemcsok, D.; Wichmann, K.; Frenking, G. Organometallics 2004, 23, 3640.
15 Green, J. C.; Herbert, B. J. J. Chem. Soc., Dalton Trans. 2005, 7, 1214.
103 16 Mercs, L.; Labat, G.; Neels, A.; Ehlers, A.; Albrecht, M. Organometallics 2006, 25, 5648.
17 Cavallo, L.; Correa, A.; Costabile, C.; Jacobsen, H. J. Organomet. Chem. 2005, 690, 5407.
18 Garrison, J. C.; Youngs, W. J. Chem. Rev., 2005, 105, 3978.
19 Arduengo, A. J. III; Dias, H. V. R.; Calabrese, J.C.; Davidson, F. Organometallics 1993, 12, 3405.
20 Chung, M. Bull. Kor. Chem. Soc. 2002, 23, 921.
21 Fox, M. A.; Mahon, M. F.; Patmore, N. J.; Weller, A. S. Inorg. Chem. 2002, 41, 4567.
22 a. Caballero, A.; Diez- Barra, E.; Jalo'n, F. A.; Merino, S.; Tejeda, J. J. Organomet. Chem. 2001, 395, 617. b. Caballero, A.; Diez- Barra, E.; Jalo'n, F. A.; Merino, S.; Rodriguez, A. M.; Tejeda, J. J. Organomet. Chem. 2001, 627, 263.
23 Lin, I.J.B.; Vasam, C.S. Comment Inorg. Chem. 2004, 25, 75
24 Guerret, O.; Sole´, S.; Gornitzka, H.; Teichert, M.; Trinquier, G.; Bertrand, G. J. Am. Chem. Soc. 1997, 119, 6668.
25 Guerret, O, Sole´, S., Gornitzka, H.; Trinquier, G.; Bertrand, G. J. Organomet. Chem. 2000, 600, 112.
26 Wang, H. M. J.; Lin, I. J. B. Organometallics 1998, 17, 972.
27 Tulloch, A. A. D.; Danopoulos, A. A.; Winston, S.; Kleinhenz, S.; Eastham, G. J. Chem. Soc., Dalton Trans. 2000, 4499.
28 Some examples: a. Nielsen, D. J.; Cavell, K. J.; Skelton, B. W.; White, A. H. Organometallics 2006, 25, 4850. b. Lee, C. K.; Vasam, C. S.; Huang, T. W.; Wang, H. M. J.; Yang, R. Y.; Lee, C. S.; Lin, I. J. B. Organometallics 2006, 25, 3768. c. Lee, H. M.; Chiu, P. L.; Hu, C.–H.; Lai, C. –L.; Chou, Y.–C. J. Organomet. Chem. 2005, 690, 403.
29 Turkmen, H.; Sahin, O.; Buyukgungor, O.; Cetinkaya, B. Eur. J. Inorg. Chem. 2006, 23, 491.
30 Garrison, J. C.; Simons, R. S.; Tessier, C. A.; Youngs, W. J. J. Organomet. Chem. 2003, 673, 1.
104 31 Kascatan-Nebioglu, A.; Panzner, M. J.; Garrison, J. C.; Tessier, C. A.; Youngs, W. J. Organometallics 2004, 23, 1928.
32 Quezada, C. A.; Garrison, J. C.; Panzner, M. J.; Tessier, C. A.; Youngs, W. J. Organometallics 2004, 23, 4846.
34 Wang, R.; Zeng, Z.; Twamley, B.; Piekarski, M.M.; Shreeve, J. M. Eur. J. Org. Chem. 2007, 655.
35 Nishioka, T.; Shibata, T.; Kinoshita, I. Organometallics 2007, 26, 1126.
36 Poyatos, M.; Maisse-Francois, A.; Bellemin-Laponnaz, S.; Gade, L. H. Organometallics 2006, 25, 2634.
37 Russel, A. D.; Path, F. R., Hugo, W. B. Prog. Med. Chem. 1994, 31, 351. 38 Lansdown, A.B.G. Br. J. Nurs. 2004, 13, S6.
39 Von Naegelli, V. Deut. schr. Schweiz. Naturforsch. Ges. 33 (1893), 174.
40 Dunn, P. M. Arch. Dis. Child. Fetal Neonatal Ed. 2000, 83, 158.
41 Silver Colloids. http://www.silver-colloids.com/Book/SilverColloids-s.pdf (accessed July 2006).
42 Lansdown, A. B. G. Wound Repair Reagen. 2002, 10, 130.
43 Moyer, C.A. Arch Surg 1965, 90, 812.
44 Fox, C. Arch. Surg. 1968, 96, 1840.
45 Baenziger, N. C., Struss, A. W. Inorg. Chem. 1976, 15, 1807.
46 a. Graham, C. Br. J. Nurs. 2005, 14, S22. b. Nanocrystalline Silver. org. http://www.nanocrystallinesilver.org/nanomods/p1/sec3.htm (accessed July 2006).
47 Lansdown, A.B.G. J. Wound Care 2002, 11, 125.
48 Silver, S. FEMS Microbiol. Rev. 2003, 27, 341.
49 Gupta, A.; Maynes, M.; Silver, S. Appl. Environ. Microbiol. 1998, 64, 5042.
50 A. Melaiye, Synthesis and Antimicrobial Properties of Silver(I) N- Heterocyclic Carbene Complexes Ph. D. Thesis 2005.
105 51 Wells, T. N. C.; Scully, P.; Paravicini, G.; I Proudfoot, A. E.; Payton, M. A. Biochemistry 1995, 34, 7896.
52 Demling, R.; DeSanti, L. Wound. Suppl. 1998, 13, 5.
53 Lansdown, A.B.G.; Sampson, B.; Laupattarakasem, P.; Vuttivirojana, A. Br. J. Dermatol. 1997, 137, 728.
54 Morgan, D. Hospital Pharmacist 2002, 9, 261.
55 Kunkley, H.; Vogler, A. Inorg. Chem. Commun. 2007, 10, 226.
56 Lockhart, S. P.; Rushworth, A.; Azmy, A. A.; Raine, P. A. Burns Incl. Therm. Inj. 1983, 10, 9.
57 Maitre, S.; Michel, J. L.; Varlet, F.; Cambazard, F. Ann. Dermatol. Venereol. 2002, 129, 1038.
58 Fraser, J. F.; Leila, C.; Margit, K.; Kimble, R. M. ANZ J. Surg. 2004, 74, 139.
59 Hollinger, M. A. Crit. Rev. Toxicol. 1996, 26, 255.
60 Hidalgo, E.; Dominguez, C. Toxicol. Lett. 1998, 98, 169.
61 Liu, J.; Kershaw, W. C.; Klaassen, C. D. Toxicol. Appl. Pharmacol. 1991, 107, 27.
62 Hussain, S.; Anner, R. M.; Anner, B. M. Biochem. Biopphys. Res. Commun. 1992, 189, 1444.
63 Ghosh, S.; Banthia, A. K.; J. Biomed. Mater. Res. 2004, 71A, 1.
64 Bosetti, M.; Masse, A.; Tobin, E.; Cannas, M. Biomaterials 2002, 23, 887.
65 Alt, V.; Bechert, T.; Steinrücke, P.; Wagener, M.; Seideld, P.; Dingeldeind, E.; Domanne, E.; Schnettlera, R. Biomaterials 2004, 25, 4383.
66 Modak, S. M.; Stanford, J. W.; Bradshaw, W.; Fox C. L. J. Panminerva Med. 1983, 25, 181.
67 Pirnay, J. P.; De Vos, D.; Cochez, C.; Bilocq, F.; Pirson, J.; Struelens, M. ; Duinslaeger, L.; Cornelis, P.; Zizi, M.; Vanderkelen A. J. Clin. Microbiol. 2003, 41, 1192.
68 Modak, S.; Fox, C. L. J. J. Trauma 1985, 25, 27.
69 McHugh, S. L.; Moellering, R. C.; Hopkins, C. C.; Swartz, M. N. Lancet 1975, 1, 235. 106 70 Gupta, A.; Matsui, K.; Lo, J. F.; Silver, S. Nat. Med. 1999, 5, 183.
71 Deshpande, L. M.; Chopade, B. A. Biometals 1994, 7, 49.
72 Starodub, M. E.; Trevors, J. T. J. Med. Microbiol. 1989, 29, 101.
73 Gupta, L. K.; Jindal, R.; Beri, H. K.; Chhibber, S.; Folia Microbiol. 1992, 37, 245.
74 Drousou, A.; Falabella, A.; Kirsner, R. S. Wounds 2003, 15, 149.
75 Melaiye, A.; Simons, R. S.; Milsted, A.; Pingitore, F.; Wesdemiotis, C.; Tessier, C. A. Youngs, W. J. J. Med. Chem. 2004, 47, 973.
76 Andrews, J. M. J. Antimicrob. Chemother. 2001, 48, 5.
77 Melaiye, A.; Sun, Z.; Hindi, K.; Milsted, A.; Ely, D.; Reneker, D. H.; Tessier, C. A.; Youngs, W. J. J. Am. Chem. Soc. 2005, 127, 2285.
78 Reneker, D. H.; Yarin, A. L.; Fong, H.; Koombhongse, S. J. Appl. Phys. 2000, 87, 4531.
79 Atiyeh, B. S.; Ionnovich, J.; Al- Amm, C. A.; El- Musa, K. A. Curr. Pharm. Biotechnol. 2002, 3, 179.
80 Garrison, J.C.; Simons, R.S.; Kofron, W. G.; Tessier, C. A.; Youngs, W. J. Chem. Commun. 2001, 1780.
81 Ratjen, F.; Döring, G. Lancet 2003, 361, 681.
82 Cystic Fibrosis Foundation. http://www.cff.org/AboutCF/ (accessed January 2007).
83 McKone, E. F.; Aitken, M. L. Drug Discovery Today 2004, 1, 137.
84 Rowe, M. S.; Miller, S.; Sorscher, E. J. N. Engl. J. Med. 2005, 352, 1992.
85 McCarty, N. A. J. Exp. Biol. 2000, 203, 1947.
86 Rodgers, H. C.; Knox, A. J. Eur. Respir. J. 2001, 17, 1314.
87 Rosenstein, B. J.; Zeitlin, P. L. Lancet 1998, 351, 277.
88 Verkman, A. S.; Song, Y.; Thiagarajah, J. R. Am. J. Cell Physiol. 2003, 284, C2.
89 Saiman, L.; Siegel, J. Clin. Microbiol. Rev. 2004, 17, 57.
107 90 Kalish, L. A.; Waltz, D. A.; Dovey, M.; Potter-Bynoe, G.; Alexander J. McAdam, A. J.; LiPuma, J. J.; Craig Gerard, C.; Donald Goldmann, D. Am. J. Respir. Crit. Care Med. 2006, 173, 421.
91 Lyczak, J.B.; Cannon, C.L.; Pier, G.B. Clin. Microbiol Rev., 2002, 15, 194.
92 O’Riordan, T. G. Respir. Care 2000, 45, 837.
93 Moss, R. B. Chest 2001, 120, 107S.
94 Conway, S. P. Chronic Respir. Disease 2005, 2, 35.
95 Hori, M.; Kataoka, T.; Shimizu, H.; Imai, E.; Matsumoto, Y. Chem. Pharm. Bull. 1985, 33, 3681.
96 Paderi, C. Archivio di Farmacologia Sperimentale e Scienze Affini, 1926, 41, 92.
97 Bredereck, H.; Christmann, O.; Koser, W.; Schellenberg, P.; Nast, R. Chem.Ber. 1962, 95, 1812.
98 Ivanov, E.I.; Kalayanov, G.D.; Yaroshchenko, I.M.; Stepanov, D.E. Khimiya Geterotsiklicheskikh Soedinenii, 1989, 11, 1570.
99 Schütz, J.; Herrmann, W. A. J. Organomet. Chem. 2004, 689, 2995.
100 Colacio-Rodriguez, E.; Salas-Peregrin, J. M.; Lopez-Gonzalez, J. D.; Valenzuela Calahorro, C. Anales de Quimica, Serie B: Quimica Inorganica y Quimica Analitica, 1984, 80, 49.
101 Some recent examples: a. Simons, R. S.; Custer, P.; Tessier, C. A.; Youngs, W. J. Organometallics 2003, 22, 1979. b. Chianese, A. R.; Li, X.; Janzen, M. C.; Faller, J. W.; Crabtree, R. H. Organometallics 2003, 22, 1663. c. Chiu, P. L.; Lee, H. M. Organometallics 2005, 24, 1692. d. Flahaut, A.; Baltaze, J.-P.; Roland, S.; Mangeney, P. J. Organometal. Chem. 2006, 69, 3498.
102 Lee, K. M.; Wang, H. M. J.; Lin, I. J. B. J. Chem. Soc., Dalton Trans. 2002, 14, 2852.
103 Zhang, G.; Yang, G.; Chen, Q.; Ma, J. S. Cryst. Growth Des. 2005, 5, 661.
104 Bu, X. -H; Chen, W.; Hou, W. –F.; Du, M.; Zhang, R. –H.; Brisse, F. Inorg. Chem. 2002, 41, 3477.
105 Aslanidis, P.; Divanidis, S.; Cox, P. J.; Karagiannidis, P. Polyhedron 2005, 24, 853.
106 Bondi, A. J. Phys. Chem. 1964, 68, 441. 108 107 S. Durmus, Silver(I) and Gold(I) Rhodium N-Heterocyclic Carbene Complexes Ph. D. Thesis, The University of Akron, December 2006.
108 Sheldrick, G. M. SHELX97: Programs for Crystal Structural Analysis; University of Göttingen, Göttingen, Germany 1997.
109 Landsdown, A. B. G. British Journal of Nursing. 2004, 13, S6.
110 Landsdown, A. B. G. J. Wound Care, 2002, 11, 125.
111 Landsown, A. B; Williams, A. J. Wound Care, 2004, 13, 131.
112 Hostynek, J. J.; Hinz, R. S.; Lorence, C. Crit. Rev. Toxicol., 1993, 23, 171.
113 Cropp, G. J. Am. J. Med. 1996, 100(1A), 19S.
114 a. Hirao, I.; Kito, T.; Funamoto, T.; Murakami, T.; Usami, K. Bull. Chem. Soc. Jpn. 1976, 49, 2775. b. Casadei, M. A.; Cesa,S.; Rossi, L. Eur. J. Org. Chem. 2000, 2445. c. Verdecchia, M.; Feroci, M.; Palombi, L.; Rossi, L. J. Org. Chem. 2002, 67, 8287.
115 a. Bhat, P. G.; Flanagan, D. R.; Donovan, M. D. J. Pharm Sci. 1996 85, 624. b. Wesley, A. W.; Qureshi, A. R.; Forstner, G. G.; Forstner, J. F. In Mucus in Health and Disease; Chantler, E. N.; Elder, J. B.; Elstein, M.; Eds.; Plenum: New York, NY; 1982 2, 145.
116 a. Janssen, A. P. J.; Heeres, J.; Hermans, H. K. F. Imidazolium Salts. US Patent 3, 991, 202, 1976. b. Klötzer, W.; Link, H.; Müssner, R.; Schiestl, W.; Singewald, N. Antimicrobial 1,3- disubstituted/ imidazolium salts. US Patent 4,814,332, 1989. c. Pernak, J.: RogoĪa, J.; Mirska I. Eur. J. Med. Chem. 2001, 36, 313. d. Demberelnyamba, D.; Kim, K- S.; Choi, S.; Park, S- Y.; Lee, H.; Kim, C- J.; Yoo, I- D. Bioorg. Med. Chem. 2004, 12, 853. e. Pernak, J.; Sobaszkiewicz, K.; Foksowicz- Flaczyk, J. Chem. Eur. J. 2004, 10, 3479. 117 a. Osman, F; McCready, S. Mol. Gen. Genet. 1998, 260, 319. b. Abratt, V. R.; Peak, M. J.; Peak, J. G.; Santangelo, J. D.; Woods, D. R. Can. J. Microbiol. 1990, 36, 490. c. Selby, C. P.; Sancar, A. Prog. Clin. Biol. Res. 1990, 340A, 179.
118 Li, X. Z.; Poole, K.; Nikaido, H. Antimicrob. Agents Chemother. 2003, 47, 27.
119 Medeiros, A. A.; O'Brien, T. F.; Wacker, W. E.; Yulug, N. F. J. Infect. Dis. 1971, 124, Suppl. 56.
120 Rosenberg, E. Y.; Ma, D.; Nikaido, H. J. Bacteriol. 2000, 182, 1754.
109 121 Bridges, K.; Kidson, A.; Lowbury, E. J.; Wilkins, M. D. Br. Med. J. 1979, 1, 446- 449.
122 Teitzel, G. M.; Parsek, M. R. Appl. Environ. Microbiol. 2003, 69, 2313.
123 Sondi, I.; Salopek-Sondi, B. J. Colloid Interface Sci 2004, 275, 177.
124 Functional Genomics Custom Oligos. Mouse Exonic Evidence Based Oligonucleotide (MEEBO) http://arrays.ucsf.edu/meebo.html (accessed March 2006). 125 N.C.C.L. Standards; Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard - Sixth Edition & Performance Standards for Antimicrobial Susceptibility Testing; Fifteenth Informational Supplement. 2004.
126 You, Y.; Richer, E. J.; Huang, T; Brody, S. L. Am. J. Physiol. Lung Cell. Mol. Physiol, 2002, 283, L1315.
127 Barnes, W. J. Am. J. Respir. Crit. Care Med. 2003, 167, 813.
128 Rabe, K. F.; Magnussen, H.; Dent, G. Eur. Respir. J. 1995, 8, 637.
129 Ito, K.; Lim, S.; Caramori, G.; Cosio, B.; Chung, K. F.; Adcock, I. M. ; Barnes, P. J. Proc. Ntl. Acad. Sci. U. S. A. 2002, 99, 8921.
130 Some examples: a. Maney, P. V.; Jones, J. W.; Gross, E. G.; Korns, H. M. J. Am. Pharm. Assoc. (1912-1977) 1946, 35, 266. b. Ayres, J. W. Pharmacological Treatments with N-7-Substituted Derivatives of Theophylline. U.S. Patent 4,581,359, April 8, 1986. c. Zlatkov, A.; Peikov, P.; Danchev, N.; Ivanov, D.; Tsvetkova, B. Arch. Pharm. (Weinheim, Germany) 1998, 331, 313. d. Jindal, D. P.; Minu, M.; Chattopadhaya, R. Indian Drugs 2000, 37, 1.
131 DrugBank. http://redpoll.pharmacy.ualberta.ca/drugbank (accessed Dec 2006).
132 Kascatan-Nebioglu, A.; Melaiye, A.; Hindi, K.; Durmus, S.; Panzner, M. J.; Hogue, L. A.; Mallett, R. J.; Hovis, C. E.; Coughenour, M.; Crosby, S. D.; Milsted, A.; Ely, D. L.; Tessier, C. A.; Cannon, C. L.; Youngs, W. J. J. Med. Chem. 2006, 49, 6811.
133 a. McColl, J. D.; Parker, J. M.; Ferguson, J. K. W. J. Pharmacol. Exp. Ther. 1956, 116, 343. b. Jacobi, H.; Lange, A.; Pfleger, K. Arzneim.-Forsch. 1956, 6, 41. c. Franzone, J. S.; Cirillo, R.; Reboani, M. C. Meth. Find. Exp. Clin. Pharmacol. 1991, 13, 289. d. Jacobi, H.; Pfleger, K. Die Medizinische 1955, 321.
110 134 a. Hori, M.; Kataoka, T.; Shimizu, H.; Imai, E.; Matsumoto, Y.; Kawachi, M.; Kuratani, K.; Yokomoto, M. Chem. Pharm. Bull. 1986, 34, 1328. b. Hori, M.; Kataoka, T.; Shimizu, H.; Imai, E.; Matsumoto, Y.; Kawachi, M.; Kuratani, K.; Ogura, H.; Takayanagi, H. J. Chem. Soc., Perkin Trans.1 1987, 1211.
135 a. Salas, J. M.; Colacio, E.; Moreno, M. N.; Ruiz, J.; Debaerdemaeker, T.; Via, J.; Arriortua, M. I. J. Crystallogr. Spectrosc. Res. 1989, 19, 755. b. Griffith, E. H.; Amma, E. L. J. Chem. Soc., Chem. Commun. 1979, 322. c. Norris, A. R.; Kumar, R.; Buncel, E. J. Inorg. Biochem. 1984, 21, 277.
136 Some examples: a. Badura, D.; Vahrenkamp, H. Eur. J. Inorg. Chem. 2003, 3723. b. Cozak, D.; Mardhy, A.; Olivier, M. J.; Beauchamp, A. L. Inorg. Chem. 1986, 25, 2600. c. Sorrell, T.; Marzilli, L. G.; Kistenmacher, T. J. J. Am. Chem. 1976, 98, 2181. d. Andronic, L.; Vladuta, C. Bull. Transilv. Univ. Brasov Ser. B (N.S.) 2003, 10, 145. e. Salas Peregrin, J. M.; Colacio Rodriguez, E.; Moreno Carretero, M.; Lopez Gonzalez, An. Quim. B-Inorg. Anal. 1984, 80, 167. f. Tu, A. T.; Reinosa, J. A. Biochemistry 1966, 5, 3375.
137 a. Aoki, K.; Yamazaki, H. J. Chem. Soc., Chem. Commun. 1980, 186. b. Agnew, N. H.; Appleton, T. G.; Hall, J. R.; Kilmister, G. F.; McMahon, I. J. Chem. Soc., Chem. Commun. 1979, 324.
138 Lopes, L. G. F.; Wieraszko, A.; El-Sherif, Y.; Clarke, M. J. Inorg. Chim. Acta 2001, 312, 15.
139 a. Salas, J. M.; Quirȩs M.; Romero, M. A.; Sánchez, M. P.; Salas, M. A. Polyhedron 1995, 14, 611. b. Vijayanthimala, R.; Udupa, M. R. Inorg. Chim. Acta 1990, 175, 163.
140 Brunet, M. A.; Boucherle, A.; Badinand, A.; Vigier, J. Bull. Soc. Chim. Fr. 1966 1333.
141 Edworthy, I. S.; Rodden, M.; Mungur, S. A.; Davis, K. M.; Blake, A J.; Wilson, C.; Schroeder, M.; Arnold, P. L. J. Organomet. Chem. 2005, 690, 5710- 5719.
142 Recent examples: a. Herrmann, W. A.; Baskakov, D.; Herdtweck, E.; Hoffmann, S. D.; Bunlaksananusorn, T.; Rampf, F.; Rodefeld, L. Organometallics 2006, 25, 2449. b. Mas-Marza, E.; Sanau, M.; Peris, E. Inorg. Chem. 2005, 44, 9961.
143 Clarke, M. J.; Taube, H. J. Am. Chem. Soc. 1975, 97, 1397.
144 Krentzien, H. J.; Clarke, M. J.; Taube, H. Bioinorg. Chem. 1975, 4, 143.
145 Johnson, A.; O’Connell, L.A.; Clarke, M. J. Inorg. Chim. Acta 1993, 210, 151.
146 Beck, W.; Kottmair, N. Chem. Ber. 1976, 109, 970. 111 147 Herrmann, W. A.; Schütz, J.; Frey, G. D.; Herdtweck, E. Organometallics 2006, 25, 2437.
148 Frey, G. D.; Schütz, J.; Herrmann, W. A. J. Organomet. Chem. 2006, 691, 2403.
149 Tubaro, C.; Biffis, A.; Gonzato, C.; Zecca, M.; Basato, M. J. Mol. Catal. A: Chem. 2006, 248, 93.
150 Kang, T.; Feng, Q.; Luo, M. Synlett 2005, 15, 2305.
151 Viciu, M. S.; Stevens, E. D.; Petersen, J. L.; Nolan, S. P. Organometallics 2004, 23, 3752.
152 Muehlhofer, M.; Strassner, T.; Herrmann, W. A. J. Organomet. Chem. 2002, 660, 121.
153 Quezada, C. A.; Garrison, J. C.; Tessier, C. A.; Youngs, W. J. J. Organomet. Chem. 2003, 671, 183.
154 Ahrens, S.; Herdtweck, E.; Goutal,S.; Strassner, T. Eur. J. Inorg. Chem. 2006, 1268.
155 Praetorius, J. M.; Kotyk, M. W.; Webb, J. D.; Wang, R.; Crudden, C. M. Organometallics 2007, 26, 1057.
156 Baker, M. V.; Brown, D. H.; Simpson, P. V.; Skelton, B. W.; White, A. H.; Williams, C. C. J. Organomet. Chem. 2006, 691, 5845.
157 Frey, G. D.; Rentzsch, C. F.; von Preysing, D.; Scherg, T.; Muehlhofer, M.; Herdtweck, E.; Herrmann, W. A. J. Organomet. Chem. 2006, 691, 5725.
158 a. Berthon-Gelloz, G.; Buisine, O.; Briére J.-F.; Michaud, G.; Stérin, S.; Ge´rard Mignani, G.; Tinant, B.;, Jean-Paul Declercq, J.-P.; Chapon, D.; Marko´, I. E J. Organomet. Chem. 2005, 690, 6156. b. Ku, R.-Z.; Huang, J.-Y.; Cho, J.-Y.; Kiang, F.- M.; Reddy, R.; Chen, Y.-C.; Lee, K.-J.; Lee, J.-H, Lee, G.-H.; Peng, S.-M.; Liu, S.-T. Organometallics 1999, 18, 2145.
159 a. Poyatos, M.; Mas-MarĨa E.; Mata J. A.; Sanaú M.; Peris E. Eur. J. Inorg. Chem. 2003, 6, 1215-1221. b. Poyatos, M.; Sanaú M.; Peris E. Inorg. Chem. 2003, 42, 2572- 2576.
160 Chen, A. C.; Ren, L.; Decken, A.; Crudden, C. M. Organometallics 2000, 19, 3459- 3461.
161 Quezada, C. A. N-heterocyclic carbenes: From heterocyclynes to potential radiopharmaceuticals. Ph. D. Thesis, The University of Akron, May 2005.
112 162 McGuinness, D. S.; Cavell, K. J. Organometallics 2000, 19, 741.
163 Magill, A. M.; McGuinness, D. S.; Cavell, K. J.; Britovsek, G. J. P.; Gibson, V. C.; White, A. J. P.; Williams, D. J.; White, A. H.; Skelton, B. W. J. Organomet. Chem. 2001, 617-618, 546.
164 Efimenko, I. A.; Kurbakova, A. P.; Matoviü, Z. D.; Ponticelli, G. Transition Met. Chem. 1994, 19, 539.
165 Fergusson, J. E.; K. S. Loh Aust. J. Chem. 1973, 26, 2615.
166 Clark, R. J.; Williams, C. S. Inorg. Chem 1965, 4, 350.
113 APPENDICES
114 APPENDIX A
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C9H13F6N4O2P (CHAPTER II-1b)
Table 1. Crystal data and structure refinement for C9H13F6N4O2P.
Identification code C9H13F6N4O2P Empirical formula C9 H13 F6 N4 O2 P Formula weight 354.20 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Monoclinic Space group P2(1)/c Unit cell dimensions a = 12.7755(15) Å a= 90°. b = 6.4242(7) Å b= 111.836(2)°. c = 17.118(2) Å g = 90°. Volume 1304.1(3) Å3 Z 4 Density (calculated) 1.804 Mg/m3 Absorption coefficient 0.299 mm-1 F(000) 720 Crystal size 0.20 x 0.10 x 0.02 mm3 Theta range for data collection 2.50 to 25.00°. Index ranges -15 h 15, -7 k 7, -20 l 20 Reflections collected 8899 Independent reflections 2290 [R(int) = 0.0236] Completeness to theta = 25.00° 99.3 % 115 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.9940 and 0.9427 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 2290 / 0 / 252 Goodness-of-fit on F2 1.082 Final R indices [I>2sigma(I)] R1 = 0.0528, wR2 = 0.1244 R indices (all data) R1 = 0.0584, wR2 = 0.1279 Extinction coefficient 0.0000(11) Largest diff. peak and hole 0.778 and -0.366 e.Å-3
116 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C9H13F6N4O2P. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______P 3911(1) -158(1) 1010(1) 20(1) F(1) 3700(2) 2255(4) 1064(2) 60(1) F(2) 3277(2) -128(3) 21(1) 36(1) F(3) 5089(2) 277(4) 930(2) 42(1) F(4) 4551(2) -252(4) 2022(1) 47(1) F(5) 4149(2) -2606(3) 983(1) 33(1) F(6) 2760(2) -650(5) 1116(2) 54(1) O(1) -3(2) 2290(3) 4438(1) 22(1) O(2) 808(2) 6938(3) 2733(1) 22(1) N(1) 2628(2) 3922(4) 2729(2) 16(1) N(2) 3029(2) 1166(4) 3535(2) 15(1) N(3) 1532(2) 1566(4) 4118(1) 15(1) N(4) 462(2) 4670(4) 3644(1) 15(1) C(1) 2662(3) 5483(6) 2112(2) 23(1) C(2) 3292(2) 2300(5) 2976(2) 17(1) C(3) 3682(3) -678(5) 3955(2) 24(1) C(4) 2132(2) 2145(5) 3642(2) 14(1) C(5) 1784(3) -284(5) 4663(2) 19(1) C(6) 620(2) 2798(5) 4083(2) 15(1) C(7) -509(3) 5913(6) 3632(2) 22(1) C(8) 1024(2) 5324(5) 3129(2) 16(1) C(9) 1886(2) 3873(5) 3151(2) 14(1) ______
117 118 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C9H13F6N4O2P. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______P 19(1) 21(1) 22(1) -2(1) 9(1) 0(1) F(1) 67(2) 29(1) 65(2) -7(1) 2(1) 19(1) F(2) 38(1) 44(1) 23(1) 7(1) 7(1) 12(1) F(3) 25(1) 46(1) 55(1) 19(1) 15(1) -3(1) F(4) 46(1) 64(2) 24(1) -8(1) 6(1) 27(1) F(5) 31(1) 21(1) 38(1) 0(1) 1(1) 0(1) F(6) 28(1) 85(2) 58(2) 31(1) 26(1) 15(1) O(1) 19(1) 29(1) 21(1) 4(1) 12(1) 1(1) O(2) 27(1) 22(1) 21(1) 8(1) 12(1) 7(1) N(1) 14(1) 20(1) 15(1) -1(1) 7(1) -2(1) N(2) 11(1) 16(1) 17(1) -1(1) 5(1) 0(1) N(3) 15(1) 15(1) 15(1) 1(1) 6(1) -1(1) N(4) 15(1) 18(1) 12(1) 1(1) 5(1) 3(1) C(1) 24(2) 30(2) 19(2) 5(1) 12(1) 1(2) C(2) 12(1) 24(2) 16(1) -5(1) 6(1) -3(1) C(3) 21(2) 21(2) 34(2) 5(2) 13(2) 7(1) C(4) 12(1) 17(2) 12(1) -5(1) 2(1) -2(1) C(5) 20(2) 18(2) 19(2) 3(1) 8(1) 0(1) C(6) 14(1) 21(2) 10(1) -3(1) 3(1) -1(1) C(7) 20(2) 26(2) 20(2) 3(1) 9(1) 7(1) C(8) 16(1) 20(2) 11(1) -1(1) 3(1) -1(1) C(9) 14(1) 19(2) 10(1) -1(1) 4(1) -3(1) ______
119 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C9H13F6N4O2P. ______x y z U(eq) ______
H(1A) 2890(30) 6820(70) 2410(30) 44(11) H(1B) 1940(30) 5690(60) 1680(20) 29(10) H(1C) 3180(30) 5070(60) 1890(20) 37(11) H(2) 3850(30) 2030(50) 2820(20) 16(8) H(3A) 3220(30) -1890(60) 3860(20) 28(9) H(3B) 4290(30) -780(60) 3760(20) 25(9) H(3C) 4010(30) -460(60) 4580(30) 41(11) H(5A) 1220(30) -390(50) 4870(20) 18(8) H(5B) 1780(30) -1470(70) 4330(30) 39(11) H(5C) 2510(30) -130(50) 5120(20) 26(9) H(7A) -1150(30) 5300(60) 3280(30) 34(11) H(7B) -400(30) 7270(60) 3470(20) 26(9) H(7C) -460(30) 6040(60) 4210(30) 32(10) ______
120 APPENDIX B
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C18H24N8O4Ag, C7H8, PF6 (CHAPTER II-2b)
Table 1. Crystal data and structure refinement for C18H24N8O4Ag, C7H8, PF6.
Identification code C18H24N8O4Ag, C7H8, PF6 Empirical formula C32 H40 Ag F6 N8 O4 P Formula weight 853.56 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Orthorhombic Space group Imm2 Unit cell dimensions a = 32.090(12) Å a= 90°. b = 6.590(2) Å b= 90°. c = 8.354(3) Å g = 90°. Volume 1766.6(11) Å3 Z 2 Density (calculated) 1.605 Mg/m3 Absorption coefficient 0.697 mm-1 F(000) 872 Crystal size 0.33 x 0.18 x 0.10 mm3 Theta range for data collection 1.27 to 28.33°. Index ranges -42<=h<=41, -8<=k<=8, -11<=l<=11 Reflections collected 7814 Independent reflections 2332 [R(int) = 0.0273] Completeness to theta = 28.33° 97.1 % 121 Absorption correction Semi-empirical from equivalents Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 2332 / 1 / 174 Goodness-of-fit on F2 1.144 Final R indices [I>2sigma(I)] R1 = 0.0294, wR2 = 0.0762 R indices (all data) R1 = 0.0307, wR2 = 0.0857 Absolute structure parameter 0.99(3) Largest diff. peak and hole 0.559 and -0.494 e.Å-3
122 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C18H24N8O4Ag, C7H8, PF6. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag 0 0 -151(1) 19(1) P 10000 5000 5886(3) 25(1) F(1) 9503(1) 5000 5863(5) 49(1) F(2) 10000 5000 3940(20) 34(5) F(3) 10000 6470(30) 4520(20) 133(9) F(4) 10000 7358(11) 5657(18) 72(3) F(5) 10000 6820(20) 7100(30) 103(6) F(6) 10000 5000 7669(10) 142(9) O(1) 1603(1) 0 3705(3) 25(1) O(2) 2415(1) 0 -767(4) 28(1) N(1) 940(1) 0 -1145(5) 17(1) N(2) 854(1) 0 1424(4) 16(1) N(3) 2003(1) 0 1451(4) 18(1) N(4) 1716(1) 0 -1156(4) 16(1) C(1) 643(1) 0 35(7) 18(1) C(2) 1278(1) 0 1137(5) 16(1) C(3) 1330(1) 0 -474(4) 13(1) C(4) 2069(1) 0 -204(9) 18(1) C(5) 1624(1) 0 2245(5) 18(1) C(6) 818(2) 0 -2843(5) 23(1) C(7) 1784(2) 0 -2917(6) 30(1) C(8) 2372(1) 0 2480(5) 26(1) C(9) 659(2) 0 3020(6) 27(1) C(10) 3533(2) 0 9218(6) 35(1) C(11) 3610(2) 0 7422(6) 28(1) C(12) 4013(2) 0 6833(7) 30(1) C(13) 4084(2) 0 5189(6) 35(1) C(14) 3759(2) 0 4137(6) 37(1) C(15) 3350(2) 0 4757(11) 37(1) C(16) 3276(1) 0 6348(6) 28(1) ______123 Table 3. Bond lengths [Å] and angles [°] for C18H24N8O4Ag, C7H8, PF6. ______Ag-C(1) 2.068(4) Ag-C(1)#1 2.068(4) P-F(6) 1.489(9) P-F(3)#2 1.495(9) P-F(3) 1.495(9) P-F(4)#2 1.566(8) P-F(4) 1.566(8) P-F(5) 1.573(9) P-F(5)#2 1.573(9) P-F(1)#2 1.594(3) P-F(1) 1.594(3) P-F(2) 1.625(17) F(2)-F(3)#2 1.08(3) F(6)-F(5)#2 1.29(2) O(1)-C(5) 1.222(5) O(2)-C(4) 1.205(6) N(1)-C(1) 1.372(6) N(1)-C(3) 1.373(5) N(1)-C(6) 1.472(6) N(2)-C(1) 1.344(6) N(2)-C(2) 1.380(5) N(2)-C(9) 1.473(6) N(3)-C(5) 1.385(5) N(3)-C(4) 1.399(8) N(3)-C(8) 1.463(5) N(4)-C(3) 1.363(5) N(4)-C(4) 1.382(5) N(4)-C(7) 1.487(6) C(2)-C(3) 1.356(5) C(2)-C(5) 1.447(6) C(10)-C(11) 1.520(7) C(11)-C(12) 1.384(7)
124 C(11)-C(16) 1.398(7) C(12)-C(13) 1.392(7) C(13)-C(14) 1.364(8) C(14)-C(15) 1.410(9) C(15)-C(16) 1.350(11) C(1)-Ag-C(1)#1 171.4(3) F(6)-P-F(3)#2 139.7(10) F(6)-P-F(3) 139.7(10) F(3)#2-P-F(3) 81(2) F(6)-P-F(4)#2 97.0(6) F(3)#2-P-F(4)#2 42.7(8) F(3)-P-F(4)#2 123.3(14) F(6)-P-F(4) 97.0(6) F(3)#2-P-F(4) 123.3(14) F(3)-P-F(4) 42.7(8) F(4)#2-P-F(4) 166.0(11) F(6)-P-F(5) 49.8(9) F(3)#2-P-F(5) 170.5(15) F(3)-P-F(5) 89.8(11) F(4)#2-P-F(5) 146.9(13) F(4)-P-F(5) 47.2(8) F(6)-P-F(5)#2 49.8(9) F(3)#2-P-F(5)#2 89.8(11) F(3)-P-F(5)#2 170.5(15) F(4)#2-P-F(5)#2 47.2(8) F(4)-P-F(5)#2 146.9(13) F(5)-P-F(5)#2 99.7(18) F(6)-P-F(1)#2 90.70(18) F(3)#2-P-F(1)#2 89.46(14) F(3)-P-F(1)#2 89.46(14) F(4)#2-P-F(1)#2 89.91(2) F(4)-P-F(1)#2 89.91(3) F(5)-P-F(1)#2 90.45(12) F(5)#2-P-F(1)#2 90.45(12)
125 F(6)-P-F(1) 90.70(18) F(3)#2-P-F(1) 89.46(14) F(3)-P-F(1) 89.46(14) F(4)#2-P-F(1) 89.91(3) F(4)-P-F(1) 89.91(2) F(5)-P-F(1) 90.45(12) F(5)#2-P-F(1) 90.45(12) F(1)#2-P-F(1) 178.6(4) F(6)-P-F(2) 180.000(4) F(3)#2-P-F(2) 40.3(10) F(3)-P-F(2) 40.3(10) F(4)#2-P-F(2) 83.0(6) F(4)-P-F(2) 83.0(6) F(5)-P-F(2) 130.2(9) F(5)#2-P-F(2) 130.2(9) F(1)#2-P-F(2) 89.30(18) F(1)-P-F(2) 89.30(18) F(3)#2-F(2)-P 63.4(11) F(5)#2-F(6)-P 68.5(8) C(1)-N(1)-C(3) 109.9(3) C(1)-N(1)-C(6) 120.6(4) C(3)-N(1)-C(6) 129.5(4) C(1)-N(2)-C(2) 110.3(4) C(1)-N(2)-C(9) 124.5(4) C(2)-N(2)-C(9) 125.2(3) C(5)-N(3)-C(4) 127.3(3) C(5)-N(3)-C(8) 115.4(3) C(4)-N(3)-C(8) 117.3(3) C(3)-N(4)-C(4) 120.2(4) C(3)-N(4)-C(7) 123.1(3) C(4)-N(4)-C(7) 116.7(4) N(2)-C(1)-N(1) 105.6(3) N(2)-C(1)-Ag 124.6(4) N(1)-C(1)-Ag 129.7(4)
126 C(3)-C(2)-N(2) 107.2(3) C(3)-C(2)-C(5) 122.6(4) N(2)-C(2)-C(5) 130.2(4) C(2)-C(3)-N(4) 121.9(4) C(2)-C(3)-N(1) 106.9(3) N(4)-C(3)-N(1) 131.2(3) O(2)-C(4)-N(4) 121.9(6) O(2)-C(4)-N(3) 121.6(5) N(4)-C(4)-N(3) 116.4(4) O(1)-C(5)-N(3) 121.8(4) O(1)-C(5)-C(2) 126.5(4) N(3)-C(5)-C(2) 111.6(3) C(12)-C(11)-C(16) 119.2(5) C(12)-C(11)-C(10) 120.3(5) C(16)-C(11)-C(10) 120.5(5) C(11)-C(12)-C(13) 120.2(5) C(14)-C(13)-C(12) 120.7(5) C(13)-C(14)-C(15) 118.4(5) C(16)-C(15)-C(14) 121.6(5) C(15)-C(16)-C(11) 119.9(4) ______Symmetry transformations used to generate equivalent atoms: #1 -x,-y,z #2 -x+2,-y+1,z
127 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C18H24N8O4Ag, C7H8, PF6. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag 12(1) 20(1) 24(1) 0 0 0 P 20(1) 26(1) 30(1) 0 0 0 F(1) 17(1) 59(2) 71(2) 0 0(1) 0 F(2) 10(8) 72(15) 19(7) 0 0 0 F(3) 67(7) 190(18) 141(16) 158(15) 0 0 F(4) 37(3) 33(3) 146(11) 5(5) 0 0 F(5) 66(7) 92(9) 151(14) -99(11) 0 0 F(6) 56(6) 350(30) 16(3) 0 0 0 O(1) 29(2) 32(2) 12(1) 0 -5(1) 0 O(2) 15(1) 39(2) 29(1) 0 3(1) 0 N(1) 15(2) 17(1) 17(2) 0 -5(1) 0 N(2) 12(2) 19(2) 18(2) 0 -1(1) 0 N(3) 18(2) 18(1) 18(2) 0 -4(1) 0 N(4) 13(2) 23(2) 13(1) 0 -1(1) 0 C(1) 22(2) 15(1) 17(3) 0 -1(2) 0 C(2) 13(2) 18(2) 18(2) 0 3(1) 0 C(3) 14(2) 17(1) 7(2) 0 -4(1) 0 C(4) 17(1) 18(1) 19(2) 0 -5(3) 0 C(5) 25(2) 16(2) 13(2) 0 0(2) 0 C(6) 24(2) 30(2) 16(2) 0 -4(2) 0 C(7) 26(2) 47(3) 16(2) 0 6(2) 0 C(8) 17(2) 31(2) 29(2) 0 -7(2) 0 C(9) 25(2) 36(2) 21(2) 0 6(2) 0 C(10) 50(3) 29(2) 27(2) 0 4(2) 0 C(11) 42(2) 14(2) 28(2) 0 3(2) 0 C(12) 31(2) 19(2) 40(2) 0 -11(2) 0 C(13) 33(2) 18(2) 54(4) 0 10(2) 0 C(14) 62(4) 19(2) 29(2) 0 9(2) 0 C(15) 42(2) 17(2) 50(3) 0 -25(4) 0 C(16) 24(2) 16(2) 45(3) 0 4(2) 0 ______128 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C18H24N8O4Ag, C7H8, PF6. ______x y z U(eq) ______
H(6A) 1069 0 -3514 35 H(6B) 652 1214 -3074 35 H(6C) 652 -1214 -3074 35 H(7A) 1514 0 -3465 45 H(7B) 1941 -1214 -3223 45 H(7C) 1941 1214 -3223 45 H(8A) 2286 0 3604 38 H(8B) 2539 1214 2262 38 H(8C) 2539 -1214 2262 38 H(9A) 355 0 2903 41 H(9B) 746 1214 3609 41 H(9C) 746 -1214 3609 41 H(10A) 3800 0 9785 53 H(10B) 3374 -1214 9513 53 H(10C) 3374 1214 9513 53 H(12) 4242 0 7552 36 H(13) 4361 0 4794 42 H(14) 3806 0 3015 44 H(15) 3120 0 4037 44 H(16) 2998 0 6737 34 ______
129 APPENDIX C
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C18H24Ag2N10O10 (CHAPTER II-2d)
Table 1. Crystal data and structure refinement for C18H24Ag2N10O10.
Identification code C18H24Ag2N10O10 Empirical formula C18 H24 Ag2 N10 O10 Formula weight 756.21 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 8.4940(11) Å a= 73.089(2)°. b = 8.8197(12) Å b= 66.525(2)°. c = 9.1395(12) Å g = 76.990(2)°. Volume 596.18(14) Å3 Z 1 Density (calculated) 2.106 Mg/m3 Absorption coefficient 1.721 mm-1 F(000) 376 Crystal size 0.38 x 0.11 x 0.09 mm3 Theta range for data collection 2.43 to 28.28°. Index ranges -11 h 11, -11 k 11, -12 l 11 Reflections collected 5329 Independent reflections 2775 [R(int) = 0.0274] Completeness to theta = 26.30° 99.1 % 130 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.8605 and 0.5608 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 2775 / 0 / 185 Goodness-of-fit on F2 1.087 Final R indices [I>2sigma(I)] R1 = 0.0390, wR2 = 0.0982 R indices (all data) R1 = 0.0433, wR2 = 0.1012 Largest diff. peak and hole 1.370 and -1.738 e.Å-3
131 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C18H24Ag2N10O10. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 9882(1) 3819(1) 8510(1) 18(1) O(1) 10886(3) 1332(3) 650(3) 17(1) O(2) 6324(3) 902(3) 5514(3) 18(1) O(3) 8501(3) 4676(3) 10949(3) 17(1) O(4) 6014(3) 4226(3) 11136(3) 19(1) O(5) 6241(3) 4890(4) 13134(3) 25(1) N(1) 8383(4) 2415(3) 6664(3) 13(1) N(2) 11012(4) 2915(3) 5145(3) 13(1) N(3) 11211(4) 2046(3) 2702(3) 13(1) N(4) 8624(4) 1124(3) 3075(4) 13(1) N(5) 6861(4) 4586(3) 11773(4) 14(1) C(1) 9737(5) 2995(4) 6651(4) 14(1) C(2) 10422(4) 2311(4) 4256(4) 13(1) C(3) 10273(4) 1505(4) 2052(4) 14(1) C(4) 7756(4) 1304(4) 4693(4) 12(1) C(5) 8778(4) 1988(4) 5205(4) 13(1) C(6) 6732(4) 2286(4) 8035(4) 16(1) C(7) 12727(4) 3387(4) 4679(4) 17(1) C(8) 13008(4) 2333(4) 1665(4) 17(1) C(9) 7703(5) 529(4) 2328(4) 17(1) ______
132 Table 3. Bond lengths [Å] and angles [°] for C18H24Ag2N10O10. ______Ag(1)-C(1) 2.087(4) Ag(1)-O(3) 2.328(2) Ag(1)-O(3)#1 2.374(2) O(1)-C(3) 1.218(4) O(2)-C(4) 1.217(4) O(3)-N(5) 1.301(4) O(3)-Ag(1)#1 2.374(2) O(4)-N(5) 1.226(4) O(5)-N(5) 1.227(4) N(1)-C(1) 1.354(4) N(1)-C(5) 1.382(4) N(1)-C(6) 1.463(4) N(2)-C(2) 1.375(4) N(2)-C(1) 1.381(5) N(2)-C(7) 1.467(4) N(3)-C(2) 1.373(4) N(3)-C(3) 1.389(4) N(3)-C(8) 1.474(4) N(4)-C(3) 1.391(4) N(4)-C(4) 1.404(4) N(4)-C(9) 1.474(4) C(2)-C(5) 1.361(5) C(4)-C(5) 1.435(5)
C(1)-Ag(1)-O(3) 149.45(12) C(1)-Ag(1)-O(3)#1 142.86(11) O(3)-Ag(1)-O(3)#1 64.98(10) N(5)-O(3)-Ag(1) 121.0(2) N(5)-O(3)-Ag(1)#1 122.7(2) Ag(1)-O(3)-Ag(1)#1 115.02(10) C(1)-N(1)-C(5) 110.6(3) C(1)-N(1)-C(6) 124.1(3) C(5)-N(1)-C(6) 125.3(3) 133 C(2)-N(2)-C(1) 109.8(3) C(2)-N(2)-C(7) 128.2(3) C(1)-N(2)-C(7) 122.0(3) C(2)-N(3)-C(3) 118.8(3) C(2)-N(3)-C(8) 123.3(3) C(3)-N(3)-C(8) 117.8(3) C(3)-N(4)-C(4) 126.6(3) C(3)-N(4)-C(9) 115.2(3) C(4)-N(4)-C(9) 118.1(3) O(4)-N(5)-O(5) 123.5(3) O(4)-N(5)-O(3) 118.2(3) O(5)-N(5)-O(3) 118.3(3) N(1)-C(1)-N(2) 105.3(3) N(1)-C(1)-Ag(1) 127.5(3) N(2)-C(1)-Ag(1) 127.2(2) C(5)-C(2)-N(3) 122.1(3) C(5)-C(2)-N(2) 107.3(3) N(3)-C(2)-N(2) 130.6(3) O(1)-C(3)-N(3) 121.3(3) O(1)-C(3)-N(4) 121.1(3) N(3)-C(3)-N(4) 117.6(3) O(2)-C(4)-N(4) 122.2(3) O(2)-C(4)-C(5) 126.5(3) N(4)-C(4)-C(5) 111.4(3) C(2)-C(5)-N(1) 107.0(3) C(2)-C(5)-C(4) 123.2(3) N(1)-C(5)-C(4) 129.9(3) ______Symmetry transformations used to generate equivalent atoms: #1 -x+2,-y+1,-z+2
134 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C18H24Ag2N10O10. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 24(1) 20(1) 18(1) -8(1) -13(1) -1(1) O(1) 18(1) 23(1) 12(1) -8(1) -6(1) -1(1) O(2) 15(1) 23(1) 18(1) -5(1) -6(1) -6(1) O(3) 9(1) 26(1) 19(1) -10(1) -3(1) -5(1) O(4) 14(1) 26(1) 22(1) -8(1) -9(1) -5(1) O(5) 17(1) 42(2) 17(1) -16(1) -3(1) -5(1) N(1) 14(1) 16(1) 12(1) -3(1) -6(1) -2(1) N(2) 12(1) 18(2) 14(1) -5(1) -7(1) -2(1) N(3) 10(1) 18(1) 12(1) -4(1) -4(1) -2(1) N(4) 13(1) 15(1) 16(1) -3(1) -9(1) -4(1) N(5) 11(1) 14(1) 17(2) -4(1) -5(1) -1(1) C(1) 15(2) 11(2) 17(2) -2(1) -9(1) 0(1) C(2) 12(2) 12(2) 16(2) -3(1) -6(1) -1(1) C(3) 14(2) 12(2) 17(2) -3(1) -8(1) 1(1) C(4) 12(2) 11(2) 14(2) -2(1) -6(1) 0(1) C(5) 11(2) 16(2) 12(2) -3(1) -4(1) -1(1) C(6) 12(2) 20(2) 14(2) -8(1) -1(1) -1(1) C(7) 13(2) 23(2) 20(2) -7(1) -7(1) -6(1) C(8) 11(2) 24(2) 14(2) -5(1) -1(1) -4(1) C(9) 17(2) 19(2) 21(2) -7(1) -10(2) -2(1) ______
135 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C18H24Ag2N10O10. ______x y z U(eq) ______
H(5A) 6688 1177 8664 24 H(5B) 5781 2614 7616 24 H(5C) 6619 2980 8745 24 H(3A) 13603 2452 4535 25 H(3B) 12745 3826 5541 25 H(3C) 12977 4199 3650 25 H(6A) 13116 3466 1458 26 H(6B) 13311 2038 622 26 H(6C) 13790 1684 2225 26 H(8A) 7452 1385 1459 26 H(8B) 6617 178 3165 26 H(8C) 8428 -373 1863 26 ______
136 APPENDIX D
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE
OF C9H13N4O2I, H2O (CHAPTER III-1)
Table 1. Crystal data and structure refinement for C9H13N4O2I, H2O.
Identification code C9 H15 I N4 O3
Empirical formula C9 H15 I N4 O3 Formula weight 354.15 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 7.8807(5) Å a= 96.4480(10)°. b = 8.1331(6) Å b= 99.4090(10)°. c = 10.8982(7) Å g = 110.5710(10)°. Volume 634.19(7) Å3 Z 2 Density (calculated) 1.855 Mg/m3 Absorption coefficient 2.529 mm-1 F(000) 348 Crystal size 0.40 x 0.40 x 0.30 mm3 Theta range for data collection 1.93 to 28.27°. Index ranges -10 h 10, -10 k 10, -14 l 14 Reflections collected 5638 Independent reflections 2944 [R(int) = 0.0123]
137 Completeness to theta = 26.30° 99.1 % Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.5467 and 0.4311 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 2944 / 0 / 166 Goodness-of-fit on F2 1.090 Final R indices [I>2sigma(I)] R1 = 0.0148, wR2 = 0.0372 R indices (all data) R1 = 0.0152, wR2 = 0.0374 Largest diff. peak and hole 0.465 and -0.291 e.Å-3
138 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C9 H15 I N4 O3. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______I(1) 6827(1) 1994(1) 3494(1) 19(1) O(1) -3118(2) 5739(2) 1188(1) 18(1) O(2) -1189(2) 1174(2) 205(1) 22(1) O(3) 8301(2) 6531(2) 5205(1) 29(1) N(1) 781(2) 7800(2) 2748(1) 14(1) N(2) 2884(2) 6598(2) 2916(1) 15(1) N(3) 959(2) 3681(2) 1512(1) 15(1) N(4) -2097(2) 3500(2) 633(1) 13(1) C(1) 2507(2) 8055(2) 3264(1) 16(1) C(2) -28(2) 6094(2) 2027(1) 13(1) C(3) 1286(2) 5351(2) 2132(1) 13(1) C(4) -806(2) 2680(2) 759(1) 15(1) C(5) -1870(2) 5170(2) 1284(1) 13(1) C(6) 2384(2) 2888(2) 1593(2) 19(1) C(7) -3972(2) 2372(2) -107(2) 17(1) C(8) 4685(2) 6484(2) 3419(2) 20(1) C(9) -115(2) 9090(2) 2937(2) 20(1) ______
139 Table 3. Bond lengths [Å] and angles [°] for C9 H15 I N4 O3. ______O(1)-C(5) 1.2205(18) O(2)-C(4) 1.2125(19) N(1)-C(1) 1.317(2) N(1)-C(2) 1.3849(18) N(1)-C(9) 1.4701(19) N(2)-C(1) 1.349(2) N(2)-C(3) 1.3784(19) N(2)-C(8) 1.4743(19) N(3)-C(3) 1.3630(19) N(3)-C(4) 1.397(2) N(3)-C(6) 1.4748(18) N(4)-C(5) 1.3966(19) N(4)-C(4) 1.3972(18) N(4)-C(7) 1.4719(19) C(2)-C(3) 1.367(2) C(2)-C(5) 1.429(2)
C(1)-N(1)-C(2) 107.49(13) C(1)-N(1)-C(9) 125.67(13) C(2)-N(1)-C(9) 126.82(13) C(1)-N(2)-C(3) 106.90(13) C(1)-N(2)-C(8) 121.99(13) C(3)-N(2)-C(8) 130.97(13) C(3)-N(3)-C(4) 118.42(12) C(3)-N(3)-C(6) 123.09(13) C(4)-N(3)-C(6) 118.49(12) C(5)-N(4)-C(4) 126.50(12) C(5)-N(4)-C(7) 116.82(12) C(4)-N(4)-C(7) 115.95(12) N(1)-C(1)-N(2) 110.77(13) C(3)-C(2)-N(1) 107.44(13) C(3)-C(2)-C(5) 122.77(13) N(1)-C(2)-C(5) 129.79(13) 140 N(3)-C(3)-C(2) 122.74(13) N(3)-C(3)-N(2) 129.84(13) C(2)-C(3)-N(2) 107.40(13) O(2)-C(4)-N(3) 121.41(14) O(2)-C(4)-N(4) 121.09(14) N(3)-C(4)-N(4) 117.47(13) O(1)-C(5)-N(4) 122.48(14) O(1)-C(5)-C(2) 125.73(14) N(4)-C(5)-C(2) 111.77(12) ______Symmetry transformations used to generate equivalent atoms:
141 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C9 H15 I N4 O3. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______I(1) 18(1) 20(1) 17(1) 5(1) 4(1) 4(1) O(1) 16(1) 18(1) 20(1) 2(1) 2(1) 9(1) O(2) 22(1) 16(1) 26(1) -3(1) 1(1) 10(1) O(3) 20(1) 25(1) 38(1) 1(1) 2(1) 8(1) N(1) 15(1) 13(1) 14(1) 1(1) 3(1) 4(1) N(2) 12(1) 18(1) 14(1) 3(1) 3(1) 5(1) N(3) 14(1) 15(1) 17(1) 2(1) 3(1) 8(1) N(4) 12(1) 13(1) 14(1) 1(1) 2(1) 5(1) C(1) 16(1) 16(1) 15(1) 3(1) 5(1) 4(1) C(2) 14(1) 12(1) 14(1) 2(1) 4(1) 5(1) C(3) 13(1) 15(1) 13(1) 4(1) 5(1) 4(1) C(4) 16(1) 16(1) 15(1) 3(1) 4(1) 8(1) C(5) 15(1) 14(1) 13(1) 4(1) 5(1) 6(1) C(6) 15(1) 19(1) 26(1) 4(1) 5(1) 11(1) C(7) 13(1) 16(1) 17(1) 0(1) -1(1) 4(1) C(8) 13(1) 26(1) 20(1) 2(1) 1(1) 8(1) C(9) 21(1) 14(1) 26(1) 1(1) 5(1) 8(1) ______
142 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C9 H15 I N4 O3. ______x y z U(eq) ______
H(6) 3369 9120 3808 19 H(6A) 2750 2749 2467 28 H(6B) 3471 3671 1330 28 H(6C) 1877 1715 1036 28 H(7B) -4684 1655 436 25 H(7C) -3879 1579 -817 25 H(7A) -4601 3132 -431 25 H(8A) 5491 7598 4000 30 H(8B) 5274 6297 2719 30 H(8C) 4487 5482 3874 30 H(9A) 796 10209 3461 30 H(9B) -1139 8600 3361 30 H(9C) -600 9321 2115 30 H(3A) 9420(40) 6860(40) 5490(30) 49(8) H(3B) 8000(40) 5560(40) 4780(30) 53(8)
143 APPENDIX E
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE
OF C20H27AgN8O7, 3CH3OH (CHAPTER III-2)
Table 1. Crystal data and structure refinement for C20H27AgN8O7, 3CH3OH.
Identification code C23 H39 Ag N8 O10
Empirical formula C23 H39 Ag N8 O10 Formula weight 695.49 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 8.0385(10) Å a= 88.876(2)°. b = 9.1589(12) Å b= 78.611(2)°. c = 20.262(3) Å g = 75.225(2)°. Volume 1413.3(3) Å3 Z 2 Density (calculated) 1.634 Mg/m3 Absorption coefficient 0.783 mm-1 F(000) 720 Crystal size 0.33 x 0.28 x 0.08 mm3 Theta range for data collection 2.05 to 28.34°. Index ranges -10 h 10, -12 k 11, -27 l 27 Reflections collected 12637 Independent reflections 6599 [R(int) = 0.0342]
144 Completeness to theta = 26.30° 99.2 % Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.9400 and 0.7822 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 6599 / 0 / 394 Goodness-of-fit on F2 1.087 Final R indices [I>2sigma(I)] R1 = 0.0568, wR2 = 0.1464 R indices (all data) R1 = 0.0638, wR2 = 0.1512 Largest diff. peak and hole 2.330 and -1.920 e.Å-3
145 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C20H27AgN8O7, 3CH3OH. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 9519(1) 7282(1) 7483(1) 21(1) O(1) 7472(4) 13923(3) 10099(1) 24(1) O(2) 12612(3) 10332(3) 9430(1) 23(1) O(3) 6891(4) 4345(4) 5346(2) 27(1) O(4) 12258(4) 1067(3) 4638(2) 29(1) O(5) 8708(5) 1587(4) 6892(2) 38(1) O(6) 9842(5) 2662(4) 7594(2) 43(1) O(7) 6979(5) 3547(4) 7561(2) 40(1) O(8) 6500(4) 6376(3) 8093(2) 28(1) O(9) 713(5) 4735(4) 8266(2) 48(1) O(10) 3020(5) 868(5) 7028(2) 52(1) N(1) 7990(4) 10074(4) 8488(2) 18(1) N(2) 10740(4) 9099(4) 8477(2) 19(1) N(3) 7464(4) 12127(4) 9337(2) 18(1) N(4) 10021(4) 12132(4) 9758(2) 18(1) N(5) 8565(4) 5636(4) 6347(2) 20(1) N(6) 11330(4) 4788(4) 6355(2) 19(1) N(7) 9576(4) 2670(4) 5015(2) 23(1) N(8) 12069(4) 2807(4) 5450(2) 22(1) C(1) 9426(5) 8945(4) 8195(2) 20(1) C(2) 8445(5) 10904(4) 8938(2) 17(1) C(3) 8259(5) 12804(4) 9752(2) 18(1) C(4) 11094(5) 10858(4) 9374(2) 19(1) C(5) 10183(5) 10299(4) 8942(2) 18(1) C(6) 6276(5) 10252(5) 8302(2) 23(1) C(7) 5588(5) 12766(5) 9355(2) 26(1) C(8) 10823(5) 12854(5) 10207(2) 23(1) C(9) 12540(5) 8148(5) 8313(2) 24(1) C(10) 9824(5) 5822(4) 6663(2) 20(1)
146 C(11) 9236(5) 4491(4) 5861(2) 20(1) C(12) 8408(5) 3889(4) 5407(2) 21(1) C(13) 11347(5) 2121(5) 5015(2) 23(1) C(14) 10978(5) 3953(4) 5872(2) 18(1) C(15) 6729(5) 6474(5) 6526(2) 25(1) C(16) 8843(6) 1903(5) 4554(2) 27(1) C(17) 13959(5) 2307(5) 5415(2) 27(1) C(18) 12985(5) 4632(5) 6576(2) 28(1) C(19) 8465(6) 2687(5) 7380(2) 32(1) C(20) 7238(6) 1527(5) 6611(2) 31(1) C(21) 6403(6) 6353(5) 8799(2) 29(1) C(22) 2356(6) 3969(5) 8397(2) 32(1) C(23) 2918(7) -307(6) 6598(3) 39(1) ______
147 Table 3. Bond lengths [Å] and angles [°] for C20H27AgN8O7, 3CH3OH. ______Ag(1)-C(10) 2.091(4) Ag(1)-C(1) 2.096(4) O(1)-C(3) 1.211(5) O(2)-C(4) 1.219(5) O(3)-C(12) 1.215(5) O(4)-C(13) 1.224(5) O(5)-C(19) 1.377(6) O(5)-C(20) 1.422(6) O(6)-C(19) 1.260(6) O(7)-C(19) 1.241(6) O(8)-C(21) 1.418(5) O(9)-C(22) 1.401(5) O(10)-C(23) 1.426(6) N(1)-C(2) 1.358(5) N(1)-C(1) 1.378(5) N(1)-C(6) 1.468(5) N(2)-C(1) 1.334(5) N(2)-C(5) 1.387(5) N(2)-C(9) 1.463(5) N(3)-C(2) 1.364(5) N(3)-C(3) 1.392(5) N(3)-C(7) 1.465(5) N(4)-C(3) 1.395(5) N(4)-C(4) 1.403(5) N(4)-C(8) 1.469(5) N(5)-C(10) 1.345(5) N(5)-C(11) 1.380(5) N(5)-C(15) 1.456(5) N(6)-C(14) 1.368(5) N(6)-C(10) 1.375(5) N(6)-C(18) 1.459(5) N(7)-C(13) 1.384(5) N(7)-C(12) 1.402(5) 148 N(7)-C(16) 1.473(5) N(8)-C(14) 1.368(5) N(8)-C(13) 1.385(5) N(8)-C(17) 1.459(5) C(2)-C(5) 1.367(5) C(4)-C(5) 1.422(5) C(11)-C(14) 1.365(5) C(11)-C(12) 1.429(5) C(10)-Ag(1)-C(1) 170.83(15) C(19)-O(5)-C(20) 117.7(4) C(2)-N(1)-C(1) 110.0(3) C(2)-N(1)-C(6) 129.0(3) C(1)-N(1)-C(6) 121.0(3) C(1)-N(2)-C(5) 111.0(3) C(1)-N(2)-C(9) 124.9(3) C(5)-N(2)-C(9) 124.1(3) C(2)-N(3)-C(3) 119.3(3) C(2)-N(3)-C(7) 123.0(3) C(3)-N(3)-C(7) 117.7(3) C(3)-N(4)-C(4) 126.7(3) C(3)-N(4)-C(8) 116.0(3) C(4)-N(4)-C(8) 117.3(3) C(10)-N(5)-C(11) 110.7(3) C(10)-N(5)-C(15) 124.2(3) C(11)-N(5)-C(15) 125.1(3) C(14)-N(6)-C(10) 110.3(3) C(14)-N(6)-C(18) 128.5(3) C(10)-N(6)-C(18) 121.1(3) C(13)-N(7)-C(12) 126.7(3) C(13)-N(7)-C(16) 116.8(3) C(12)-N(7)-C(16) 116.6(3) C(14)-N(8)-C(13) 118.1(3) C(14)-N(8)-C(17) 123.7(3) C(13)-N(8)-C(17) 118.2(3) N(2)-C(1)-N(1) 105.5(3) 149 N(2)-C(1)-Ag(1) 126.9(3) N(1)-C(1)-Ag(1) 127.5(3) N(1)-C(2)-N(3) 130.4(3) N(1)-C(2)-C(5) 107.6(3) N(3)-C(2)-C(5) 122.1(3) O(1)-C(3)-N(3) 122.2(3) O(1)-C(3)-N(4) 120.7(3) N(3)-C(3)-N(4) 117.0(3) O(2)-C(4)-N(4) 121.5(4) O(2)-C(4)-C(5) 126.6(4) N(4)-C(4)-C(5) 111.8(3) C(2)-C(5)-N(2) 106.0(3) C(2)-C(5)-C(4) 123.0(4) N(2)-C(5)-C(4) 131.0(3) N(5)-C(10)-N(6) 105.3(3) N(5)-C(10)-Ag(1) 127.2(3) N(6)-C(10)-Ag(1) 127.4(3) C(14)-C(11)-N(5) 106.9(3) C(14)-C(11)-C(12) 122.3(4) N(5)-C(11)-C(12) 130.8(4) O(3)-C(12)-N(7) 121.9(4) O(3)-C(12)-C(11) 126.3(4) N(7)-C(12)-C(11) 111.7(3) O(4)-C(13)-N(7) 121.2(4) O(4)-C(13)-N(8) 120.8(4) N(7)-C(13)-N(8) 118.1(3) C(11)-C(14)-N(6) 106.8(3) C(11)-C(14)-N(8) 123.0(4) N(6)-C(14)-N(8) 130.2(3) O(7)-C(19)-O(6) 128.2(5) O(7)-C(19)-O(5) 118.6(4) O(6)-C(19)-O(5) 113.1(4)
______Symmetry transformations used to generate equivalent atoms:
150 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C20H27AgN8O7, 3CH3OH. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 14(1) 23(1) 26(1) -7(1) -2(1) -6(1) O(1) 19(1) 22(1) 30(2) -5(1) -3(1) -6(1) O(2) 11(1) 29(2) 31(2) -5(1) -5(1) -6(1) O(3) 18(1) 35(2) 31(2) 0(1) -7(1) -11(1) O(4) 28(2) 26(2) 32(2) -9(1) -2(1) -10(1) O(5) 31(2) 37(2) 47(2) -8(2) -9(2) -7(2) O(6) 40(2) 43(2) 54(2) 2(2) -19(2) -16(2) O(7) 31(2) 36(2) 52(2) -10(2) 0(2) -10(2) O(8) 24(2) 28(2) 31(2) -2(1) -2(1) -9(1) O(9) 30(2) 48(2) 63(2) -14(2) -24(2) 5(2) O(10) 37(2) 59(3) 64(3) -12(2) -6(2) -22(2) N(1) 11(1) 19(2) 25(2) -3(1) -2(1) -6(1) N(2) 10(1) 21(2) 24(2) -3(1) -2(1) -3(1) N(3) 8(1) 20(2) 26(2) -4(1) -2(1) -3(1) N(4) 13(2) 20(2) 23(2) -2(1) -5(1) -7(1) N(5) 13(2) 23(2) 24(2) -1(1) -1(1) -6(1) N(6) 11(1) 22(2) 24(2) -3(1) -2(1) -6(1) N(7) 19(2) 26(2) 26(2) -3(1) -3(1) -12(1) N(8) 16(2) 23(2) 26(2) -6(1) 0(1) -9(1) C(1) 10(2) 24(2) 27(2) 2(2) -2(1) -7(2) C(2) 11(2) 20(2) 22(2) 1(1) -2(1) -8(1) C(3) 14(2) 20(2) 21(2) 2(1) -3(1) -7(1) C(4) 14(2) 24(2) 22(2) 1(2) -2(1) -8(2) C(5) 12(2) 20(2) 22(2) -2(1) -2(1) -5(1) C(6) 10(2) 29(2) 30(2) -6(2) -3(1) -6(2) C(7) 11(2) 28(2) 40(2) -10(2) -6(2) -2(2) C(8) 17(2) 27(2) 27(2) -6(2) -4(2) -11(2) C(9) 13(2) 26(2) 30(2) -8(2) -2(2) -2(2) C(10) 13(2) 21(2) 26(2) -1(2) -1(1) -6(1)
151 C(11) 14(2) 23(2) 24(2) -1(2) -2(1) -8(2) C(12) 21(2) 21(2) 24(2) 1(2) -4(2) -12(2) C(13) 23(2) 22(2) 24(2) -1(2) 0(2) -13(2) C(14) 14(2) 20(2) 22(2) -1(1) 0(1) -8(1) C(15) 12(2) 29(2) 31(2) -5(2) -3(2) -3(2) C(16) 30(2) 28(2) 28(2) -2(2) -8(2) -16(2) C(17) 17(2) 24(2) 37(2) -9(2) -1(2) -2(2) C(18) 15(2) 33(2) 36(2) -12(2) -4(2) -8(2) C(19) 29(2) 32(2) 39(2) 0(2) -5(2) -14(2) C(20) 30(2) 35(2) 31(2) -2(2) -8(2) -12(2) C(21) 21(2) 36(2) 31(2) 3(2) -7(2) -9(2) C(22) 26(2) 31(2) 38(2) 2(2) -11(2) -3(2) C(23) 34(3) 38(3) 45(3) 1(2) -5(2) -11(2) ______
152 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C20H27AgN8O7, 3CH3OH. ______x y z U(eq) ______
H(8) 6752 5486 7937 42 H(9) 161 4105 8199 71 H(10) 2049 1188 7292 78 H(6A) 5403 10167 8703 34 H(6B) 6364 9462 7968 34 H(6C) 5919 11247 8110 34 H(7A) 5414 13115 8908 40 H(7B) 5141 13619 9681 40 H(7C) 4953 11991 9489 40 H(8A) 11210 13700 9981 34 H(8B) 11835 12115 10321 34 H(8C) 9959 13229 10620 34 H(9A) 12595 7315 8006 36 H(9B) 12904 7738 8727 36 H(9C) 13326 8754 8096 36 H(15A) 6036 5817 6765 37 H(15B) 6297 6820 6116 37 H(15C) 6621 7349 6818 37 H(16A) 9732 1551 4145 40 H(16B) 7815 2609 4434 40 H(16C) 8493 1036 4776 40 H(17A) 14485 3154 5294 41 H(17B) 14474 1489 5073 41 H(17C) 14189 1939 5854 41 H(18A) 13332 3637 6769 42 H(18B) 12839 5422 6918 42 H(18C) 13895 4731 6190 42 H(20A) 6409 1135 6943 47
153 H(20B) 7635 859 6208 47 H(20C) 6659 2544 6490 47 H(21A) 7502 5717 8897 43 H(21B) 5423 5942 9014 43 H(21C) 6217 7383 8975 43 H(22A) 3273 4021 8005 48 H(22B) 2374 2910 8485 48 H(22C) 2569 4442 8791 48 H(23A) 2639 -1140 6871 59 H(23B) 4048 -673 6288 59 H(23C) 1997 85 6340 59 ______P.S. Space group is changed from triclinic P1 to monoclinic P21/m by using Platon.
154 APPENDIX F
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C11H15AgN4 O4, 2(H2O) (CHAPER III-4)
Table 1. Crystal data and structure refinement for C11H15AgN4 O4, 2(H2O).
Identification code C11H15AgN4 O4, 2(H2O)
Empirical formula C11 H19 Ag N4 O6 Formula weight 411.16 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Monoclinic Space group P21/m Unit cell dimensions a = 8.4027(8) Å a= 90°. b = 6.2961(6) Å b= 98.243(2)°. c = 14.1856(14) Å g = 90°. Volume 742.73(12) Å3 Z 2 Density (calculated) 1.839 Mg/m3 Absorption coefficient 1.393 mm-1 F(000) 416 Crystal size 0.21 x 0.18 x 0.03 mm3 Theta range for data collection 2.45 to 28.29°. Index ranges -11 h 10, -8 k 8, -18 l 18 Reflections collected 6661 Independent reflections 1940 [R(int) = 0.0200] Completeness to theta = 28.29° 96.6 % 155 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.9594 and 0.7586 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 1940 / 0 / 150 Goodness-of-fit on F2 1.093 Final R indices [I>2sigma(I)] R1 = 0.0244, wR2 = 0.0598 R indices (all data) R1 = 0.0256, wR2 = 0.0604 Largest diff. peak and hole 1.593 and -0.229 e.Å-3
156 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C11H15AgN4 O4, 2(H2O). U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 1015(1) 2500 5930(1) 18(1) O(1) 888(2) 2500 474(1) 21(1) O(2) -3425(2) 2500 2097(1) 19(1) O(3) 2097(2) 2500 7375(1) 21(1) O(4) 4423(3) 2500 6794(2) 29(1) O(5) 2274(3) 7500 3240(2) 29(1) O(6) -257(3) 2500 8499(2) 31(1) N(1) -994(3) 2500 3909(2) 15(1) N(2) 1564(3) 2500 3846(2) 15(1) N(3) -1245(3) 2500 1290(2) 17(1) N(4) 1437(3) 2500 2085(2) 15(1) C(1) 442(3) 2500 4464(2) 17(1) C(2) -795(3) 2500 2957(2) 15(1) C(3) 818(3) 2500 2925(2) 14(1) C(4) -1969(3) 2500 2124(2) 16(1) C(5) 390(3) 2500 1240(2) 17(1) C(6) -2298(3) 2500 372(2) 22(1) C(7) 3168(3) 2500 2035(2) 20(1) C(8) 3306(3) 2500 4197(2) 20(1) C(9) -2540(3) 2500 4268(2) 19(1) C(10) 3640(4) 2500 7475(2) 21(1) C(11) 4478(4) 2500 8489(2) 26(1) ______
157 Table 3. Bond lengths [Å] and angles [°] for C11H15AgN4 O4, 2(H2O). ______Ag(1)-C(1) 2.067(3) Ag(1)-O(3) 2.1198(19) O(1)-C(5) 1.220(4) O(2)-C(4) 1.219(3) O(3)-C(10) 1.283(4) O(4)-C(10) 1.244(4) O(5)-H(5A) 0.83(5) O(5)-H(5B) 0.74(5) O(6)-H(6A') 0.81(6) O(6)-H(6B') 0.85(6) N(1)-C(1) 1.343(3) N(1)-C(2) 1.385(3) N(1)-C(9) 1.462(3) N(2)-C(3) 1.366(3) N(2)-C(1) 1.376(3) N(2)-C(8) 1.477(3) N(3)-C(5) 1.386(3) N(3)-C(4) 1.406(3) N(3)-C(6) 1.466(3) N(4)-C(3) 1.366(3) N(4)-C(5) 1.381(3) N(4)-C(7) 1.466(3) C(2)-C(3) 1.363(3) C(2)-C(4) 1.426(4) C(6)-H(6A) 0.9800 C(6)-H(6C) 0.9800 C(6)-H(6B) 0.9800 C(7)-H(7C) 0.9800 C(7)-H(7B) 0.9800 C(7)-H(7A) 0.9800 C(8)-H(8B) 0.9800 C(8)-H(8A) 0.9800 C(8)-H(8C) 0.9800 158 C(9)-H(9A) 0.9800 C(9)-H(9C) 0.9800 C(9)-H(9B) 0.9800 C(10)-C(11) 1.508(4) C(11)-H(11C) 0.9800 C(11)-H(11A) 0.9800 C(11)-H(11B) 0.9800
C(1)-Ag(1)-O(3) 168.19(9) C(10)-O(3)-Ag(1) 113.15(18) H(5A)-O(5)-H(5B) 98(4) H(6A')-O(6)-H(6B') 105(5) C(1)-N(1)-C(2) 110.4(2) C(1)-N(1)-C(9) 124.3(2) C(2)-N(1)-C(9) 125.3(2) C(3)-N(2)-C(1) 110.3(2) C(3)-N(2)-C(8) 128.2(2) C(1)-N(2)-C(8) 121.5(2) C(5)-N(3)-C(4) 126.4(2) C(5)-N(3)-C(6) 115.6(2) C(4)-N(3)-C(6) 118.0(2) C(3)-N(4)-C(5) 118.8(2) C(3)-N(4)-C(7) 123.1(2) C(5)-N(4)-C(7) 118.1(2) N(1)-C(1)-N(2) 105.5(2) N(1)-C(1)-Ag(1) 130.6(2) N(2)-C(1)-Ag(1) 123.99(19) C(3)-C(2)-N(1) 107.0(2) C(3)-C(2)-C(4) 123.1(2) N(1)-C(2)-C(4) 130.0(2) C(2)-C(3)-N(2) 106.9(2) C(2)-C(3)-N(4) 122.2(2) N(2)-C(3)-N(4) 130.9(2) O(2)-C(4)-N(3) 121.8(2) O(2)-C(4)-C(2) 126.7(3) 159 N(3)-C(4)-C(2) 111.5(2) O(1)-C(5)-N(4) 121.1(2) O(1)-C(5)-N(3) 120.9(2) N(4)-C(5)-N(3) 117.9(2) N(3)-C(6)-H(6A) 109.5 N(3)-C(6)-H(6C) 109.5 H(6A)-C(6)-H(6C) 109.5 N(3)-C(6)-H(6B) 109.5 H(6A)-C(6)-H(6B) 109.5 H(6C)-C(6)-H(6B) 109.5 N(4)-C(7)-H(7C) 109.5 N(4)-C(7)-H(7B) 109.5 H(7C)-C(7)-H(7B) 109.5 N(4)-C(7)-H(7A) 109.5 H(7C)-C(7)-H(7A) 109.5 H(7B)-C(7)-H(7A) 109.5 N(2)-C(8)-H(8B) 109.5 N(2)-C(8)-H(8A) 109.5 H(8B)-C(8)-H(8A) 109.5 N(2)-C(8)-H(8C) 109.5 H(8B)-C(8)-H(8C) 109.5 H(8A)-C(8)-H(8C) 109.5 N(1)-C(9)-H(9A) 109.5 N(1)-C(9)-H(9C) 109.5 H(9A)-C(9)-H(9C) 109.5 N(1)-C(9)-H(9B) 109.5 H(9A)-C(9)-H(9B) 109.5 H(9C)-C(9)-H(9B) 109.5 O(4)-C(10)-O(3) 123.5(3) O(4)-C(10)-C(11) 120.9(3) O(3)-C(10)-C(11) 115.5(3) C(10)-C(11)-H(11C) 109.5 C(10)-C(11)-H(11A) 109.5 H(11C)-C(11)-H(11A) 109.5 C(10)-C(11)-H(11B) 109.5 160 H(11C)-C(11)-H(11B) 109.5 H(11A)-C(11)-H(11B) 109.5 ______Symmetry transformations used to generate equivalent atoms:
161 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C11H15AgN4 O4, 2(H2O). The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 21(1) 18(1) 14(1) 0 1(1) 0 O(1) 19(1) 30(1) 15(1) 0 4(1) 0 O(2) 9(1) 25(1) 23(1) 0 2(1) 0 O(3) 22(1) 25(1) 15(1) 0 0(1) 0 O(4) 21(1) 42(1) 22(1) 0 1(1) 0 O(5) 27(1) 40(1) 19(1) 0 4(1) 0 O(6) 27(1) 47(2) 19(1) 0 4(1) 0 N(1) 11(1) 16(1) 18(1) 0 3(1) 0 N(2) 11(1) 16(1) 17(1) 0 1(1) 0 N(3) 13(1) 23(1) 14(1) 0 1(1) 0 N(4) 10(1) 19(1) 17(1) 0 4(1) 0 C(1) 16(1) 14(1) 20(1) 0 1(1) 0 C(2) 12(1) 15(1) 19(1) 0 4(1) 0 C(3) 13(1) 13(1) 17(1) 0 2(1) 0 C(4) 18(1) 13(1) 18(1) 0 3(1) 0 C(5) 15(1) 18(1) 19(1) 0 3(1) 0 C(6) 18(1) 31(2) 16(1) 0 -2(1) 0 C(7) 12(1) 26(1) 23(1) 0 7(1) 0 C(8) 13(1) 27(2) 19(1) 0 -1(1) 0 C(9) 14(1) 24(1) 20(1) 0 7(1) 0 C(10) 25(1) 19(1) 19(1) 0 -2(1) 0 C(11) 32(2) 24(2) 18(1) 0 -7(1) 0 ______
162 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C11H15AgN4 O4, 2(H2O). ______x y z U(eq) ______
H(6A) -2012 3692 -16 33 H(6C) -3419 2646 479 33 H(6B) -2165 1163 38 33 H(7C) 3342 2374 1369 30 H(7B) 3675 1297 2400 30 H(7A) 3643 3829 2302 30 H(8B) 3769 1131 4050 30 H(8A) 3478 2726 4887 30 H(8C) 3827 3643 3885 30 H(9A) -2358 2364 4964 28 H(9C) -3191 1303 3992 28 H(9B) -3106 3833 4091 28 H(11C) 4535 3956 8736 38 H(11A) 5568 1932 8508 38 H(11B) 3874 1612 8882 38 H(5A) 3230(60) 7500 3150(30) 42(12) H(6A') 40(70) 2500 9070(40) 68(17) H(5B) 1900(60) 7500 2740(40) 45(14) H(6B') 610(70) 2500 8250(40) 78(19) ______
163 APPENDIX G
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C10H15IN4O3 (CHAPTER IV-1a)
Table 1. Crystal data and structure refinement for C10 H15 I N4 O3.
Identification code C10 H15 I N4 O3
Empirical formula C10 H15 I N4 O3 Formula weight 366.16 Temperature 273(2) K Wavelength 0.71073 Å Crystal system Monoclinic Space group P2(1)/c Unit cell dimensions a = 8.1744(12) Å a= 90°. b = 12.8082(19) Å b= 97.714(2)°. c = 12.7571(19) Å g = 90°. Volume 1323.6(3) Å3 Z 4 Density (calculated) 1.548 Mg/m3 Absorption coefficient 1.833 mm-1 F(000) 615 Crystal size 0.15x 0.09 x 0.05 mm3 Theta range for data collection 2.26 to 28.31°. Index ranges -10 h 10, -16 k 16, -16 l 16 Reflections collected 11291 Independent reflections 3103 [R(int) = 0.0257] Completeness to theta = 28.31° 94.3 % 164 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.912 and 0.773 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 3103 / 0 / 167 Goodness-of-fit on F2 1.263 Final R indices [I>2sigma(I)] R1 = 0.0389, wR2 = 0.0796 R indices (all data) R1 = 0.0433, wR2 = 0.0814 Largest diff. peak and hole 1.153 and -0.963 e.Å-3
165 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C10 H15 I N4 O3. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______I(1) 7014(1) 1422(1) 3434(1) 23(1) N(3) -761(4) 3768(2) 4918(2) 18(1) N(4) 1930(4) 3567(2) 4434(2) 18(1) N(1) 1969(4) 3762(2) 2502(2) 16(1) N(2) -619(4) 4202(2) 2065(2) 16(1) O(1) -1189(4) 6145(2) 700(2) 25(1) C(7) 3662(5) 3509(3) 2329(3) 23(1) C(1) 791(4) 4020(3) 1698(3) 16(1) C(4) -1505(4) 4106(3) 3910(3) 16(1) C(5) 874(4) 3460(3) 5195(3) 17(1) C(2) 1256(4) 3789(3) 3420(3) 15(1) C(6) -2166(4) 4543(3) 1427(3) 21(1) C(3) -348(4) 4064(3) 3154(3) 15(1) C(8) -2276(5) 5718(3) 1366(3) 26(1) O(2) -2926(3) 4407(2) 3760(2) 22(1) O(3) 1380(3) 3158(2) 6084(2) 23(1) C(9) -1875(5) 3613(3) 5715(3) 23(1) C(10) 3703(4) 3408(3) 4777(3) 23(1) ______
166 Table 3. Bond lengths [Å] and angles [°] for C10 H15 I N4 O3. ______N(3)-C(5) 1.393(5) N(3)-C(4) 1.414(4) N(3)-C(9) 1.467(5) N(4)-C(2) 1.366(4) N(4)-C(5) 1.390(5) N(4)-C(10) 1.471(5) N(1)-C(1) 1.351(4) N(1)-C(2) 1.377(4) N(1)-C(7) 1.466(5) N(2)-C(1) 1.322(5) N(2)-C(3) 1.389(4) N(2)-C(6) 1.475(4) O(1)-C(8) 1.419(5) C(4)-O(2) 1.215(4) C(4)-C(3) 1.439(5) C(5)-O(3) 1.216(4) C(2)-C(3) 1.356(5) C(6)-C(8) 1.509(6)
C(5)-N(3)-C(4) 126.7(3) C(5)-N(3)-C(9) 116.7(3) C(4)-N(3)-C(9) 116.2(3) C(2)-N(4)-C(5) 118.2(3) C(2)-N(4)-C(10) 124.5(3) C(5)-N(4)-C(10) 117.2(3) C(1)-N(1)-C(2) 107.4(3) C(1)-N(1)-C(7) 122.1(3) C(2)-N(1)-C(7) 130.5(3) C(1)-N(2)-C(3) 107.6(3) C(1)-N(2)-C(6) 125.5(3) C(3)-N(2)-C(6) 126.8(3) N(2)-C(1)-N(1) 109.9(3) O(2)-C(4)-N(3) 121.7(3) 167 O(2)-C(4)-C(3) 127.4(3) N(3)-C(4)-C(3) 110.9(3) O(3)-C(5)-N(4) 121.1(3) O(3)-C(5)-N(3) 121.4(3) N(4)-C(5)-N(3) 117.4(3) C(3)-C(2)-N(4) 123.0(3) C(3)-C(2)-N(1) 107.4(3) N(4)-C(2)-N(1) 129.6(3) N(2)-C(6)-C(8) 111.4(3) C(2)-C(3)-N(2) 107.6(3) C(2)-C(3)-C(4) 122.8(3) N(2)-C(3)-C(4) 129.4(3) O(1)-C(8)-C(6) 112.2(3) ______Symmetry transformations used to generate equivalent atoms:
168 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C10 H15 I N4 O3. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______I(1) 27(1) 21(1) 21(1) 0(1) 6(1) 6(1) N(3) 22(2) 21(2) 11(1) -4(1) -2(1) -5(1) N(4) 18(1) 18(1) 18(1) 2(1) 0(1) -1(1) N(1) 18(1) 13(1) 17(1) 0(1) 3(1) 1(1) N(2) 18(1) 18(1) 13(1) 3(1) 0(1) -2(1) O(1) 29(2) 25(1) 21(1) 6(1) 0(1) 1(1) C(7) 21(2) 28(2) 23(2) -2(2) 6(1) 3(2) C(1) 20(2) 14(2) 15(2) -1(1) 2(1) -3(1) C(4) 20(2) 13(2) 16(2) 1(1) 1(1) -3(1) C(5) 21(2) 13(2) 17(2) -1(1) 1(1) -3(1) C(2) 20(2) 10(2) 15(2) 0(1) 2(1) -2(1) C(6) 18(2) 31(2) 13(2) 3(1) -2(1) -1(2) C(3) 20(2) 13(2) 14(2) 1(1) 1(1) -3(1) C(8) 25(2) 35(2) 17(2) 2(2) 0(2) 11(2) O(2) 22(1) 23(1) 20(1) 0(1) 3(1) 0(1) O(3) 31(2) 21(1) 15(1) 2(1) 0(1) 0(1) C(9) 26(2) 27(2) 17(2) 0(2) 6(1) -4(2) C(10) 17(2) 28(2) 22(2) 2(2) -1(1) 4(2) ______
169 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C10 H15 I N4 O3. ______x y z U(eq) ______
H(1) -268 6215 1037 38 H(7A) 3720 3472 1583 35 H(7B) 3975 2848 2650 35 H(7C) 4399 4042 2641 35 H(1A) 949 4064 990 19 H(6A) -3099 4273 1739 25 H(6B) -2219 4259 718 25 H(8A) -3399 5918 1100 31 H(8B) -2010 6006 2071 31 H(9A) -2477 2973 5572 34 H(9B) -2636 4186 5691 34 H(9C) -1242 3577 6405 34 H(10A) 3995 2701 4631 34 H(10B) 3944 3538 5523 34 H(10C) 4329 3880 4402 34 ______
170 APPENDIX H
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C11H17IN4O4 (CHAPTER IV-1b)
Table 1. Crystal data and structure refinement for C11 H17 I N4 O4.
Identification code C11 H17 I N4 O4
Empirical formula C11 H17 I N4 O4 Formula weight 396.19 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Orthorhombic Space group Pbca Unit cell dimensions a = 7.6526(5) Å a= 90°. b = 15.1108(9) Å b= 90°. c = 24.4607(15) Å g = 90°. Volume 2828.6(3) Å3 Z 8 Density (calculated) 1.861 Mg/m3 Absorption coefficient 2.284 mm-1 F(000) 1568 Crystal size 0.26 x 0.23 x 0.07 mm3 Theta range for data collection 1.67 to 28.27°. Index ranges -9 £h £9, -19 £k £20, -32 £l £32 Reflections collected 23382 Independent reflections 3426 [R(int) = 0.0293] Completeness to theta = 28.27° 97.7 % 171 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.8565 and 0.5881 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 3426 / 0 / 186 Goodness-of-fit on F2 1.228 Final R indices [I>2sigma(I)] R1 = 0.0690, wR2 = 0.1291 R indices (all data) R1 = 0.0736, wR2 = 0.1311 Largest diff. peak and hole 3.572 and -1.296 e.Å-3
172 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C11 H17 I N4 O4. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______I(1) 9983(1) 6486(1) 3763(1) 23(1) O(1) 9189(6) 8364(3) 4561(2) 24(1) O(2) 6519(6) 9660(3) 4485(2) 25(1) O(3) 4032(5) 7716(3) 3357(2) 18(1) O(4) 956(6) 9374(3) 2133(2) 26(1) N(1) 2967(6) 9068(3) 4205(2) 17(1) N(2) 1159(6) 10142(3) 4009(2) 16(1) N(3) 855(6) 9830(3) 3017(2) 18(1) N(4) 2358(6) 8512(3) 2755(2) 18(1) C(1) 7340(8) 8172(4) 4669(3) 21(1) C(2) 6126(8) 8767(4) 4341(2) 19(1) C(3) 4250(8) 8535(4) 4506(2) 17(1) C(4) 2132(7) 9766(4) 4401(2) 17(1) C(5) 113(8) 10936(4) 4109(3) 24(1) C(6) 1454(7) 9682(4) 3535(2) 15(1) C(7) 2564(8) 9001(4) 3655(2) 16(1) C(8) 3095(7) 8348(4) 3267(2) 16(1) C(9) 2796(9) 7884(5) 2312(3) 28(1) C(10) 1372(7) 9250(4) 2605(2) 18(1) C(11) -190(9) 10620(4) 2863(3) 25(1) ______
173 Table 3. Bond lengths [Å] and angles [°] for C11 H17 I N4 O4. ______O(1)-C(1) 1.468(7) O(2)-C(2) 1.426(7) O(3)-C(8) 1.215(7) O(4)-C(10) 1.212(7) N(1)-C(4) 1.322(7) N(1)-C(7) 1.385(7) N(1)-C(3) 1.468(7) N(2)-C(4) 1.340(7) N(2)-C(6) 1.371(7) N(2)-C(5) 1.463(7) N(3)-C(6) 1.365(7) N(3)-C(10) 1.394(7) N(3)-C(11) 1.485(7) N(4)-C(10) 1.396(7) N(4)-C(8) 1.397(7) N(4)-C(9) 1.478(7) C(1)-C(2) 1.522(8) C(2)-C(3) 1.532(8) C(6)-C(7) 1.366(8) C(7)-C(8) 1.428(8)
C(4)-N(1)-C(7) 107.6(5) C(4)-N(1)-C(3) 125.5(5) C(7)-N(1)-C(3) 126.6(5) C(4)-N(2)-C(6) 107.4(5) C(4)-N(2)-C(5) 122.2(5) C(6)-N(2)-C(5) 130.3(5) C(6)-N(3)-C(10) 118.2(5) C(6)-N(3)-C(11) 123.3(5) C(10)-N(3)-C(11) 118.3(5) C(10)-N(4)-C(8) 126.6(5) C(10)-N(4)-C(9) 116.2(5) C(8)-N(4)-C(9) 116.9(5) 174 O(1)-C(1)-C(2) 112.1(5) O(2)-C(2)-C(1) 107.5(5) O(2)-C(2)-C(3) 110.5(5) C(1)-C(2)-C(3) 107.3(4) N(1)-C(3)-C(2) 111.6(4) N(1)-C(4)-N(2) 110.4(5) N(3)-C(6)-C(7) 122.2(5) N(3)-C(6)-N(2) 130.3(5) C(7)-C(6)-N(2) 107.5(5) C(6)-C(7)-N(1) 107.1(5) C(6)-C(7)-C(8) 123.7(5) N(1)-C(7)-C(8) 129.2(5) O(3)-C(8)-N(4) 122.6(5) O(3)-C(8)-C(7) 126.3(5) N(4)-C(8)-C(7) 111.0(5) O(4)-C(10)-N(3) 121.1(5) O(4)-C(10)-N(4) 121.1(6) N(3)-C(10)-N(4) 117.8(5) ______Symmetry transformations used to generate equivalent atoms:
175 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C11 H17 I N4 O4. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______I(1) 20(1) 26(1) 24(1) 7(1) 0(1) 0(1) O(1) 23(2) 17(2) 31(2) -5(2) -3(2) 4(2) O(2) 33(2) 13(2) 30(2) 3(2) -7(2) -1(2) O(3) 13(2) 16(2) 24(2) -1(2) 2(2) 2(2) O(4) 31(2) 24(2) 23(2) -4(2) -12(2) -2(2) N(1) 16(2) 17(2) 18(2) 2(2) 0(2) 0(2) N(2) 16(2) 13(2) 19(2) 1(2) 2(2) 0(2) N(3) 14(2) 17(2) 21(2) -3(2) -5(2) 3(2) N(4) 15(2) 17(2) 23(2) -8(2) -6(2) 4(2) C(1) 17(3) 21(3) 24(3) 1(2) -3(2) -4(2) C(2) 23(3) 18(3) 16(3) 8(2) 3(2) 1(2) C(3) 25(3) 15(3) 11(2) 7(2) -3(2) 2(2) C(4) 16(3) 15(3) 20(3) 1(2) 4(2) -3(2) C(5) 18(3) 22(3) 33(3) 2(2) 5(3) 5(3) C(6) 15(3) 13(2) 18(3) 0(2) 0(2) -4(2) C(7) 17(3) 14(3) 15(2) 1(2) 0(2) -3(2) C(8) 13(2) 11(2) 24(3) -6(2) 0(2) -3(2) C(9) 23(3) 30(3) 31(3) -17(3) -11(3) 4(3) C(10) 11(3) 20(3) 22(3) -1(2) -6(2) -5(2) C(11) 30(3) 16(3) 29(3) -1(2) -11(3) 6(3) ______
176 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C11 H17 I N4 O4. ______x y z U(eq) ______
H(1) 9544 8041 4304 35 H(2) 6050 10004 4259 38 H(1A) 7104 8253 5064 25 H(1B) 7096 7546 4577 25 H(2A) 6301 8672 3941 23 H(3A) 4035 7900 4433 20 H(3B) 4101 8635 4903 20 H(4) 2210 9971 4767 20 H(5A) 2 11032 4504 36 H(5B) -1051 10859 3948 36 H(5C) 687 11449 3941 36 H(9A) 1771 7797 2078 42 H(9B) 3148 7316 2471 42 H(9C) 3759 8124 2093 42 H(11A) -1329 10596 3045 38 H(11B) -359 10629 2466 38 H(11C) 430 11158 2976 38 ______
177 APPENDIX I
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C35H35BN4O4, H2O (CHAPTER IV-1c)
Table 1. Crystal data and structure refinement for C35 H35 B N4 O4, H2O
Identification code C35 H35 B N4 O4, H2O
Empirical formula C35 H37 B N4 O5 Formula weight 602.48 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Orthorhombic Space group Pbca Unit cell dimensions a = 15.9058(18) Å a= 90°. b = 18.200(2) Å b= 90°. c = 21.116(3) Å g = 90°. Volume 6112.8(12) Å3 Z 8 Density (calculated) 1.309 Mg/m3 Absorption coefficient 0.088 mm-1 F(000) 2544 Crystal size 0.43 x 0.16 x 0.11 mm3 Theta range for data collection 1.93 to 28.30°. Index ranges -21<=h<=21, -23<=k<=23, -27<=l<=28 Reflections collected 49968 Independent reflections 7330 [R(int) = 0.0902] Completeness to theta = 28.30° 96.5 % 178 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.990 and 0.983 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 7330 / 0 / 410 Goodness-of-fit on F2 1.043 Final R indices [I>2sigma(I)] R1 = 0.0704, wR2 = 0.1483 R indices (all data) R1 = 0.1403, wR2 = 0.1761 Largest diff. peak and hole 0.361 and -0.558 e.Å-3
179 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C35 H35 B N4 O4, H2O. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______O(1) 2612(1) 405(1) 4780(1) 49(1) O(2) 729(1) 2033(1) 5622(1) 46(1) O(3) -1226(2) 3017(1) 5369(1) 71(1) O(4) -975(1) 2036(1) 4762(1) 43(1) O(5) 769(2) 9720(2) 264(2) 122(1) N(1) 454(1) 2570(1) 4282(1) 32(1) N(2) 1105(1) 2065(1) 3482(1) 30(1) N(3) 2014(1) 1214(1) 4095(1) 34(1) N(4) 1692(2) 1234(1) 5202(1) 37(1) C(1) 522(2) 2559(1) 3665(1) 31(1) C(2) 1423(2) 1762(1) 4025(1) 30(1) C(3) 1026(2) 2069(1) 4526(1) 31(1) C(4) 2140(2) 921(2) 4698(2) 39(1) C(5) 1112(2) 1811(1) 5163(1) 35(1) C(6) 1274(2) 1911(2) 2812(1) 36(1) C(7) 2507(2) 911(2) 3567(2) 47(1) C(8) 1797(2) 899(2) 5832(1) 45(1) C(9) -79(2) 3064(2) 4656(1) 38(1) C(10) -810(2) 2698(2) 4975(1) 42(1) C(11) -1671(2) 1642(2) 5041(2) 67(1) C(12) 743(2) 10178(1) 1889(1) 28(1) C(13) 316(2) 10767(1) 1605(1) 32(1) C(14) 721(2) 11352(2) 1316(1) 36(1) C(15) 1596(2) 11362(2) 1291(1) 41(1) C(16) 2041(2) 10796(2) 1571(1) 39(1) C(17) 1623(2) 10225(1) 1868(1) 32(1) C(18) 740(2) 8743(1) 2262(1) 28(1) C(19) 1239(2) 8527(1) 1747(1) 31(1) C(20) 1584(2) 7827(2) 1692(1) 35(1)
180 C(21) 1442(2) 7307(2) 2158(2) 37(1) C(22) 946(2) 7494(2) 2676(1) 35(1) C(23) 605(2) 8195(1) 2720(1) 32(1) C(24) -673(2) 9329(1) 1974(1) 28(1) C(25) -838(2) 9349(1) 1328(1) 34(1) C(26) -1574(2) 9051(2) 1067(2) 39(1) C(27) -2165(2) 8729(2) 1458(2) 43(1) C(28) -2033(2) 8717(2) 2099(2) 41(1) C(29) -1302(2) 9011(2) 2355(1) 35(1) C(30) 152(2) 9865(1) 3002(1) 28(1) C(31) 658(2) 9669(1) 3514(1) 33(1) C(32) 569(2) 9975(2) 4111(1) 35(1) C(33) -24(2) 10523(1) 4219(1) 31(1) C(34) -516(2) 10752(1) 3718(1) 31(1) C(35) -435(2) 10428(1) 3130(1) 30(1) B(1) 251(2) 9539(2) 2284(2) 28(1) ______
181 Table 3. Bond lengths [Å] and angles [°] for C35 H35 B N4 O4, H2O. ______O(1)-C(4) 1.215(3) O(2)-C(5) 1.214(3) O(3)-C(10) 1.211(4) O(4)-C(10) 1.313(4) O(4)-C(11) 1.444(4) N(1)-C(1) 1.309(3) N(1)-C(3) 1.386(3) N(1)-C(9) 1.466(3) N(2)-C(1) 1.347(3) N(2)-C(2) 1.369(3) N(2)-C(6) 1.467(3) N(3)-C(2) 1.378(3) N(3)-C(4) 1.396(4) N(3)-C(7) 1.470(4) N(4)-C(5) 1.400(4) N(4)-C(4) 1.400(4) N(4)-C(8) 1.472(4) C(2)-C(3) 1.353(4) C(3)-C(5) 1.433(4) C(9)-C(10) 1.501(4) C(12)-C(17) 1.403(4) C(12)-C(13) 1.404(4) C(12)-B(1) 1.632(4) C(13)-C(14) 1.386(4) C(14)-C(15) 1.393(4) C(15)-C(16) 1.382(4) C(16)-C(17) 1.384(4) C(18)-C(19) 1.402(4) C(18)-C(23) 1.406(4) C(18)-B(1) 1.646(4) C(19)-C(20) 1.393(4) C(20)-C(21) 1.383(4) C(21)-C(22) 1.391(4) 182 C(22)-C(23) 1.389(4) C(24)-C(25) 1.390(4) C(24)-C(29) 1.408(4) C(24)-B(1) 1.654(4) C(25)-C(26) 1.403(4) C(26)-C(27) 1.381(4) C(27)-C(28) 1.371(4) C(28)-C(29) 1.389(4) C(30)-C(31) 1.395(4) C(30)-C(35) 1.412(4) C(30)-B(1) 1.636(4) C(31)-C(32) 1.385(4) C(32)-C(33) 1.392(4) C(33)-C(34) 1.381(4) C(34)-C(35) 1.379(4)
C(10)-O(4)-C(11) 117.9(3) C(1)-N(1)-C(3) 107.8(2) C(1)-N(1)-C(9) 126.4(2) C(3)-N(1)-C(9) 125.6(2) C(1)-N(2)-C(2) 106.4(2) C(1)-N(2)-C(6) 122.0(2) C(2)-N(2)-C(6) 131.5(2) C(2)-N(3)-C(4) 118.1(2) C(2)-N(3)-C(7) 123.7(2) C(4)-N(3)-C(7) 118.2(2) C(5)-N(4)-C(4) 126.5(2) C(5)-N(4)-C(8) 115.9(2) C(4)-N(4)-C(8) 117.5(2) N(1)-C(1)-N(2) 110.7(2) C(3)-C(2)-N(2) 108.4(2) C(3)-C(2)-N(3) 122.3(3) N(2)-C(2)-N(3) 129.2(3) C(2)-C(3)-N(1) 106.7(2) C(2)-C(3)-C(5) 123.6(2) 183 N(1)-C(3)-C(5) 128.9(3) O(1)-C(4)-N(3) 120.9(3) O(1)-C(4)-N(4) 121.3(3) N(3)-C(4)-N(4) 117.7(2) O(2)-C(5)-N(4) 122.3(3) O(2)-C(5)-C(3) 126.3(3) N(4)-C(5)-C(3) 111.4(2) N(1)-C(9)-C(10) 114.7(2) O(3)-C(10)-O(4) 124.6(3) O(3)-C(10)-C(9) 121.3(3) O(4)-C(10)-C(9) 114.1(2) C(17)-C(12)-C(13) 115.1(2) C(17)-C(12)-B(1) 122.6(2) C(13)-C(12)-B(1) 122.0(2) C(14)-C(13)-C(12) 123.3(3) C(13)-C(14)-C(15) 119.5(3) C(16)-C(15)-C(14) 119.0(3) C(15)-C(16)-C(17) 120.6(3) C(16)-C(17)-C(12) 122.6(3) C(19)-C(18)-C(23) 115.0(2) C(19)-C(18)-B(1) 122.5(2) C(23)-C(18)-B(1) 122.1(2) C(20)-C(19)-C(18) 122.9(3) C(21)-C(20)-C(19) 120.1(3) C(20)-C(21)-C(22) 119.0(3) C(23)-C(22)-C(21) 119.9(3) C(22)-C(23)-C(18) 123.0(3) C(25)-C(24)-C(29) 115.9(2) C(25)-C(24)-B(1) 123.4(2) C(29)-C(24)-B(1) 120.0(2) C(24)-C(25)-C(26) 122.2(3) C(27)-C(26)-C(25) 119.8(3) C(28)-C(27)-C(26) 119.5(3) C(27)-C(28)-C(29) 120.4(3) C(28)-C(29)-C(24) 122.1(3) 184 C(31)-C(30)-C(35) 114.8(2) C(31)-C(30)-B(1) 124.7(2) C(35)-C(30)-B(1) 120.3(2) C(32)-C(31)-C(30) 122.8(3) C(31)-C(32)-C(33) 120.5(3) C(34)-C(33)-C(32) 118.2(3) C(35)-C(34)-C(33) 120.5(2) C(34)-C(35)-C(30) 123.0(3) C(12)-B(1)-C(30) 105.2(2) C(12)-B(1)-C(18) 112.7(2) C(30)-B(1)-C(18) 113.1(2) C(12)-B(1)-C(24) 112.9(2) C(30)-B(1)-C(24) 111.4(2) C(18)-B(1)-C(24) 101.8(2) ______Symmetry transformations used to generate equivalent atoms:
185 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C35 H35 B N4 O4, H2O. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______O(1) 37(1) 44(1) 66(2) 9(1) -6(1) 15(1) O(2) 64(1) 33(1) 40(1) -3(1) -2(1) 6(1) O(3) 64(2) 62(2) 88(2) -22(1) 31(2) 9(1) O(4) 39(1) 38(1) 52(1) 1(1) 11(1) 1(1) O(5) 72(2) 135(3) 160(4) 59(3) 16(2) 1(2) N(1) 32(1) 26(1) 38(1) -1(1) -1(1) 3(1) N(2) 26(1) 26(1) 38(1) 1(1) 0(1) -2(1) N(3) 25(1) 30(1) 48(2) 0(1) -2(1) 5(1) N(4) 36(1) 30(1) 44(2) 3(1) -8(1) -1(1) C(1) 28(1) 27(1) 39(2) 2(1) 0(1) -1(1) C(2) 26(1) 24(1) 41(2) 1(1) -3(1) -5(1) C(3) 31(1) 21(1) 40(2) 0(1) -4(1) -1(1) C(4) 31(2) 35(2) 50(2) 3(1) -7(1) -3(1) C(5) 40(2) 23(1) 41(2) -3(1) -3(1) -4(1) C(6) 35(2) 34(2) 39(2) 1(1) 3(1) 0(1) C(7) 40(2) 45(2) 56(2) 6(2) 8(2) 13(2) C(8) 51(2) 37(2) 48(2) 6(1) -15(2) 1(1) C(9) 43(2) 30(2) 41(2) -2(1) 2(1) 11(1) C(10) 49(2) 34(2) 43(2) -1(1) 5(1) 11(1) C(11) 57(2) 65(2) 78(3) 10(2) 20(2) 1(2) C(12) 29(1) 25(1) 31(2) -5(1) 1(1) 1(1) C(13) 31(1) 28(1) 36(2) -2(1) 0(1) 0(1) C(14) 44(2) 27(2) 36(2) 0(1) -2(1) -2(1) C(15) 50(2) 31(2) 43(2) -1(1) 10(1) -13(1) C(16) 30(1) 35(2) 50(2) -9(1) 7(1) -6(1) C(17) 28(1) 25(1) 43(2) -5(1) 2(1) -1(1) C(18) 21(1) 26(1) 38(2) -5(1) -4(1) -3(1) C(19) 24(1) 27(1) 41(2) -3(1) -2(1) -2(1) C(20) 25(1) 30(2) 51(2) -11(1) -1(1) -2(1)
186 C(21) 29(2) 23(1) 59(2) -7(1) -8(1) 1(1) C(22) 28(1) 25(1) 53(2) 3(1) -6(1) -3(1) C(23) 24(1) 29(1) 42(2) -3(1) -1(1) -3(1) C(24) 24(1) 20(1) 41(2) -2(1) 2(1) 4(1) C(25) 29(1) 27(1) 45(2) -2(1) -1(1) 2(1) C(26) 37(2) 34(2) 46(2) -6(1) -11(1) 8(1) C(27) 23(1) 35(2) 72(2) -9(2) -5(1) 3(1) C(28) 26(1) 32(2) 64(2) -9(1) 10(1) 0(1) C(29) 29(1) 30(1) 45(2) -4(1) 3(1) 2(1) C(30) 23(1) 23(1) 38(2) 2(1) 1(1) -4(1) C(31) 28(1) 26(1) 44(2) 0(1) -1(1) 1(1) C(32) 30(1) 32(2) 43(2) 2(1) -6(1) -1(1) C(33) 32(1) 28(1) 35(2) -5(1) 2(1) -7(1) C(34) 29(1) 24(1) 41(2) -2(1) 1(1) 2(1) C(35) 26(1) 27(1) 38(2) 3(1) -3(1) 0(1) B(1) 22(1) 26(2) 36(2) 2(1) -1(1) -1(1) ______
187 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C35 H35 B N4 O4, H2O. ______x y z U(eq) ______
H(1) 205 2857 3384 37 H(6A) 907 2215 2547 54 H(6B) 1164 1390 2725 54 H(6C) 1863 2023 2717 54 H(7A) 2137 629 3287 71 H(7B) 2947 588 3734 71 H(7C) 2765 1314 3329 71 H(8A) 1900 1285 6146 68 H(8B) 2274 559 5824 68 H(8C) 1285 630 5945 68 H(9A) -296 3455 4374 45 H(9B) 273 3303 4983 45 H(11A) -1525 1498 5474 100 H(11B) -1790 1202 4789 100 H(11C) -2168 1959 5048 100 H(13) -282 10764 1611 38 H(14) 405 11742 1136 43 H(15) 1883 11752 1084 49 H(16) 2638 10800 1560 46 H(17) 1945 9849 2065 38 H(19) 1345 8874 1420 37 H(20) 1919 7706 1334 42 H(21) 1679 6830 2125 45 H(22) 840 7143 2999 42 H(23) 265 8310 3077 38 H(25) -439 9572 1054 40 H(26) -1666 9071 623 47 H(27) -2659 8517 1283 52
188 H(28) -2444 8506 2370 49 H(29) -1225 8997 2801 42 H(31) 1083 9309 3451 39 H(32) 915 9810 4448 42 H(33) -89 10734 4628 38 H(34) -913 11136 3777 37 H(35) -789 10591 2797 36 ______
189 APPENDIX J
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C24H34N8O10Ag2, C2H6O (CHAPTER IV-2a)
Table 1. Crystal data and structure refinement for C24H34N8O10Ag2, C2H6O.
Identification code C24H34N8O10Ag2, C2H6O
Empirical formula C26 H40 Ag2 N8 O11 Formula weight 428.20 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 8.5766(11) Å a= 104.634(2)°. b = 12.5430(16) Å b= 97.056(2)°. c = 15.621(2) Å g = 95.866(2)°. Volume 1598.0(4) Å3 Z 4 Density (calculated) 1.780 Mg/m3 Absorption coefficient 1.296 mm-1 F(000) 868 Crystal size 0.64 x 0.43 x 0.18 mm3 Theta range for data collection 1.69 to 28.31°. Index ranges -11 h 10, -16 k 16, -20 l 20 Reflections collected 14268 Independent reflections 7389 [R(int) = 0.0307] Completeness to theta = 26.30° 99.2 % 190 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.792 and 0.517 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 7389 / 0 / 436 Goodness-of-fit on F2 1.065 Final R indices [I>2sigma(I)] R1 = 0.0399, wR2 = 0.0879 R indices (all data) R1 = 0.0506, wR2 = 0.0922 Largest diff. peak and hole 0.998 and -0.798 e.Å-3
191 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C24H34N8O10Ag2, C2H6O. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 856(1) 1246(1) 437(1) 19(1) Ag(2) 1090(1) 3889(1) 270(1) 20(1) O(1) 3148(3) -916(2) -719(2) 18(1) O(2) 4076(3) 1066(2) -2797(2) 25(1) O(3) -546(3) 1157(2) -4560(2) 32(1) O(4) 1589(3) 1623(2) 1828(2) 24(1) O(5) -851(3) 1876(2) 2105(2) 24(1) O(6) 1628(3) 6676(2) 1847(2) 24(1) O(7) -21(3) 5527(2) 4085(2) 26(1) O(8) -5318(3) 4235(2) 3407(2) 22(1) O(9) 3089(3) 3841(2) -382(2) 25(1) O(10) 1568(3) 3393(2) -1722(2) 27(1) O(11) 6863(3) 2198(3) 3195(2) 34(1) N(1) 2060(3) 970(2) -1334(2) 15(1) N(2) -489(3) 941(2) -1580(2) 15(1) N(3) 1740(3) 1111(2) -3672(2) 20(1) N(4) -760(3) 904(2) -3189(2) 19(1) N(5) 127(3) 4572(2) 2096(2) 15(1) N(6) -2007(3) 3805(2) 1155(2) 14(1) N(7) -3905(3) 3921(2) 2245(2) 15(1) N(8) -2689(3) 4930(2) 3722(2) 19(1) C(1) 4098(4) -219(3) -1096(2) 17(1) C(2) 3668(4) 948(3) -902(2) 17(1) C(3) 772(4) 1005(3) -924(2) 16(1) C(4) -2127(4) 940(3) -1384(2) 21(1) C(5) 55(4) 886(3) -2378(2) 16(1) C(6) 1645(4) 883(3) -2238(2) 15(1) C(7) 2647(4) 1013(3) -2888(2) 18(1) C(8) 2671(5) 1340(4) -4353(3) 33(1)
192 C(9) 118(4) 1065(3) -3853(2) 22(1) C(10) -2505(4) 756(3) -3391(2) 26(1) C(11) 605(4) 1911(3) 2351(2) 19(1) C(12) 1254(4) 2307(3) 3339(2) 27(1) C(13) 1956(4) 6342(3) 2639(2) 21(1) C(14) 1763(4) 5083(3) 2468(2) 18(1) C(15) -394(4) 4112(3) 1224(2) 16(1) C(16) -3019(4) 3374(3) 283(2) 18(1) C(17) -2446(4) 4078(3) 1994(2) 14(1) C(18) -1117(4) 4574(3) 2586(2) 15(1) C(19) -1144(4) 5044(3) 3515(2) 17(1) C(20) -2884(5) 5381(3) 4663(2) 30(1) C(21) -4049(4) 4344(3) 3143(2) 17(1) C(22) -5227(4) 3117(3) 1671(2) 20(1) C(23) 2886(4) 3653(3) -1234(2) 20(1) C(24) 4376(4) 3743(3) -1641(2) 24(1) C(25) 7328(5) 2147(4) 4077(3) 34(1) C(26) 5924(6) 2114(5) 4545(3) 49(1) ______
193 Table 3. Bond lengths [Å] and angles [°] for C24H34N8O10Ag2, C2H60. ______Ag(1)-C(3) 2.061(3) Ag(1)-O(4) 2.103(2) Ag(1)-Ag(1)#1 3.1947(6) Ag(1)-Ag(2) 3.3770(6) Ag(2)-C(15) 2.060(3) Ag(2)-O(9) 2.097(2) O(1)-C(1) 1.417(4) O(2)-C(7) 1.210(4) O(3)-C(9) 1.216(4) O(4)-C(11) 1.262(4) O(5)-C(11) 1.254(4) O(6)-C(13) 1.409(4) O(7)-C(19) 1.218(4) O(8)-C(21) 1.217(4) O(9)-C(23) 1.279(4) O(10)-C(23) 1.246(4) O(11)-C(25) 1.407(4) N(1)-C(3) 1.343(4) N(1)-C(6) 1.387(4) N(1)-C(2) 1.465(4) N(2)-C(5) 1.372(4) N(2)-C(3) 1.377(4) N(2)-C(4) 1.473(4) N(3)-C(9) 1.378(4) N(3)-C(7) 1.407(4) N(3)-C(8) 1.472(4) N(4)-C(5) 1.376(4) N(4)-C(9) 1.397(4) N(4)-C(10) 1.474(4) N(5)-C(15) 1.338(4) N(5)-C(18) 1.387(4) N(5)-C(14) 1.465(4) N(6)-C(17) 1.378(4) 194 N(6)-C(15) 1.381(4) N(6)-C(16) 1.464(4) N(7)-C(17) 1.367(4) N(7)-C(21) 1.394(4) N(7)-C(22) 1.472(4) N(8)-C(21) 1.396(4) N(8)-C(19) 1.403(4) N(8)-C(20) 1.473(4) C(1)-C(2) 1.512(5) C(5)-C(6) 1.355(4) C(6)-C(7) 1.438(5) C(11)-C(12) 1.511(5) C(13)-C(14) 1.521(5) C(17)-C(18) 1.358(4) C(18)-C(19) 1.426(4) C(23)-C(24) 1.501(5) C(25)-C(26) 1.485(6)
C(3)-Ag(1)-O(4) 164.65(11) C(3)-Ag(1)-Ag(1)#1 74.99(9) O(4)-Ag(1)-Ag(1)#1 113.86(7) C(3)-Ag(1)-Ag(2) 78.60(9) O(4)-Ag(1)-Ag(2) 97.40(7) Ag(1)#1-Ag(1)-Ag(2) 144.793(14) C(15)-Ag(2)-O(9) 163.85(11) C(15)-Ag(2)-Ag(1) 85.09(9) O(9)-Ag(2)-Ag(1) 96.17(7) C(11)-O(4)-Ag(1) 119.4(2) C(23)-O(9)-Ag(2) 118.8(2) C(3)-N(1)-C(6) 110.6(3) C(3)-N(1)-C(2) 124.8(3) C(6)-N(1)-C(2) 124.4(3) C(5)-N(2)-C(3) 109.3(3) C(5)-N(2)-C(4) 129.1(3) C(3)-N(2)-C(4) 121.6(3) 195 C(9)-N(3)-C(7) 127.9(3) C(9)-N(3)-C(8) 117.2(3) C(7)-N(3)-C(8) 114.8(3) C(5)-N(4)-C(9) 118.1(3) C(5)-N(4)-C(10) 123.3(3) C(9)-N(4)-C(10) 118.6(3) C(15)-N(5)-C(18) 110.6(3) C(15)-N(5)-C(14) 124.3(3) C(18)-N(5)-C(14) 124.9(3) C(17)-N(6)-C(15) 109.5(3) C(17)-N(6)-C(16) 128.7(3) C(15)-N(6)-C(16) 121.4(3) C(17)-N(7)-C(21) 118.4(3) C(17)-N(7)-C(22) 122.7(3) C(21)-N(7)-C(22) 117.4(3) C(21)-N(8)-C(19) 126.7(3) C(21)-N(8)-C(20) 115.9(3) C(19)-N(8)-C(20) 117.1(3) O(1)-C(1)-C(2) 112.1(3) N(1)-C(2)-C(1) 111.7(3) N(1)-C(3)-N(2) 105.7(3) N(1)-C(3)-Ag(1) 123.8(2) N(2)-C(3)-Ag(1) 130.3(2) C(6)-C(5)-N(2) 107.9(3) C(6)-C(5)-N(4) 122.6(3) N(2)-C(5)-N(4) 129.3(3) C(5)-C(6)-N(1) 106.3(3) C(5)-C(6)-C(7) 123.1(3) N(1)-C(6)-C(7) 129.2(3) O(2)-C(7)-N(3) 122.6(3) O(2)-C(7)-C(6) 126.8(3) N(3)-C(7)-C(6) 110.6(3) O(3)-C(9)-N(3) 122.3(3) O(3)-C(9)-N(4) 120.4(3) N(3)-C(9)-N(4) 117.3(3) 196 O(5)-C(11)-O(4) 124.4(3) O(5)-C(11)-C(12) 118.9(3) O(4)-C(11)-C(12) 116.7(3) O(6)-C(13)-C(14) 112.6(3) N(5)-C(14)-C(13) 111.9(3) N(5)-C(15)-N(6) 105.8(3) N(5)-C(15)-Ag(2) 123.0(2) N(6)-C(15)-Ag(2) 131.1(2) C(18)-C(17)-N(7) 123.0(3) C(18)-C(17)-N(6) 107.2(3) N(7)-C(17)-N(6) 129.8(3) C(17)-C(18)-N(5) 106.9(3) C(17)-C(18)-C(19) 122.8(3) N(5)-C(18)-C(19) 130.2(3) O(7)-C(19)-N(8) 121.4(3) O(7)-C(19)-C(18) 127.0(3) N(8)-C(19)-C(18) 111.5(3) O(8)-C(21)-N(7) 121.4(3) O(8)-C(21)-N(8) 121.3(3) N(7)-C(21)-N(8) 117.2(3) O(10)-C(23)-O(9) 124.3(3) O(10)-C(23)-C(24) 120.2(3) O(9)-C(23)-C(24) 115.5(3) O(11)-C(25)-C(26) 110.1(3) ______Symmetry transformations used to generate equivalent atoms: #1 -x,-y,-z
197 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C24H34N8O10Ag2, C2H6O. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 22(1) 23(1) 13(1) 5(1) 4(1) 1(1) Ag(2) 17(1) 26(1) 18(1) 5(1) 6(1) 1(1) O(1) 17(1) 18(1) 19(1) 6(1) 1(1) -2(1) O(2) 15(1) 38(2) 24(1) 11(1) 5(1) 2(1) O(3) 31(2) 49(2) 20(1) 14(1) 2(1) 9(1) O(4) 21(1) 31(1) 18(1) 4(1) 4(1) 0(1) O(5) 22(1) 27(1) 20(1) 4(1) 0(1) 3(1) O(6) 20(1) 27(1) 27(1) 12(1) 2(1) -1(1) O(7) 19(1) 38(2) 16(1) 2(1) -2(1) -4(1) O(8) 15(1) 32(1) 20(1) 6(1) 7(1) 7(1) O(9) 21(1) 32(2) 21(1) 5(1) 7(1) 1(1) O(10) 22(1) 25(1) 34(2) 10(1) 2(1) 5(1) O(11) 32(2) 49(2) 27(2) 17(1) 8(1) 16(1) N(1) 16(1) 16(1) 13(1) 4(1) 1(1) 0(1) N(2) 14(1) 17(1) 16(1) 4(1) 6(1) 2(1) N(3) 20(2) 29(2) 13(1) 6(1) 5(1) 2(1) N(4) 16(1) 24(2) 19(2) 7(1) 2(1) 5(1) N(5) 10(1) 18(1) 18(1) 7(1) 3(1) 1(1) N(6) 17(1) 14(1) 12(1) 4(1) 2(1) 0(1) N(7) 13(1) 18(1) 14(1) 5(1) 1(1) 2(1) N(8) 17(1) 26(2) 14(1) 3(1) 3(1) 3(1) C(1) 15(2) 25(2) 13(2) 6(1) 1(1) 3(1) C(2) 16(2) 19(2) 14(2) 5(1) 0(1) -1(1) C(3) 21(2) 11(2) 16(2) 6(1) 4(1) 0(1) C(4) 15(2) 24(2) 26(2) 8(2) 6(1) 5(1) C(5) 16(2) 15(2) 15(2) 3(1) 3(1) 1(1) C(6) 16(2) 16(2) 14(2) 6(1) 2(1) 2(1) C(7) 22(2) 17(2) 15(2) 4(1) 2(1) 1(1) C(8) 32(2) 52(3) 20(2) 16(2) 11(2) 0(2)
198 C(9) 26(2) 23(2) 17(2) 4(1) 3(1) 3(2) C(10) 16(2) 36(2) 26(2) 8(2) 0(2) 3(2) C(11) 24(2) 11(2) 19(2) 4(1) 2(1) -5(1) C(12) 27(2) 34(2) 17(2) 3(2) 1(2) -2(2) C(13) 12(2) 26(2) 22(2) 4(2) -1(1) -3(1) C(14) 9(2) 25(2) 20(2) 6(1) 0(1) 0(1) C(15) 16(2) 14(2) 20(2) 5(1) 5(1) 5(1) C(16) 21(2) 18(2) 12(2) 3(1) -1(1) 0(1) C(17) 15(2) 13(2) 14(2) 4(1) 4(1) 3(1) C(18) 14(2) 16(2) 16(2) 5(1) 2(1) 3(1) C(19) 16(2) 20(2) 17(2) 6(1) 2(1) 4(1) C(20) 30(2) 39(2) 17(2) 1(2) 4(2) 5(2) C(21) 21(2) 19(2) 14(2) 6(1) 3(1) 7(1) C(22) 17(2) 19(2) 21(2) 3(1) 3(1) -3(1) C(23) 20(2) 13(2) 29(2) 8(1) 6(2) 5(1) C(24) 25(2) 26(2) 26(2) 13(2) 10(2) 6(2) C(25) 37(2) 42(2) 27(2) 14(2) 5(2) 13(2) C(26) 43(3) 72(4) 43(3) 33(3) 13(2) 14(2) ______
199 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C24H34N8O10Ag2, C2H6O. ______x y z U(eq) ______
H(1) 2383 -1277 -1107 28 H(6) 648 6545 1664 36 H(11) 7659 2201 2931 50 H(1A) 3965 -542 -1752 21 H(1B) 5228 -189 -851 21 H(2A) 3746 1257 -247 20 H(2B) 4435 1424 -1119 20 H(4A) -2554 1586 -1517 32 H(4B) -2130 977 -750 32 H(4C) -2785 256 -1755 32 H(8A) 1951 1305 -4900 50 H(8B) 3394 785 -4485 50 H(8C) 3286 2084 -4126 50 H(10A) -2938 47 -3297 40 H(10B) -2829 753 -4015 40 H(10C) -2909 1368 -2994 40 H(12A) 804 2976 3611 41 H(12B) 2412 2480 3419 41 H(12C) 967 1722 3628 41 H(13A) 1233 6648 3057 25 H(13B) 3056 6656 2929 25 H(14A) 2479 4775 2046 22 H(14B) 2078 4895 3038 22 H(16A) -3430 2590 200 27 H(16B) -2398 3438 -193 27 H(16C) -3907 3804 257 27 H(20A) -3787 5802 4689 45 H(20B) -1918 5874 4990 45
200 H(20C) -3078 4768 4937 45 H(22A) -5734 3445 1221 30 H(22B) -6005 2931 2039 30 H(22C) -4822 2441 1371 30 H(24C) 4910 3090 -1634 35 H(24A) 5082 4418 -1294 35 H(24B) 4107 3779 -2260 35 H(25B) 8106 2807 4403 40 H(25A) 7843 1474 4068 40 H(26C) 5337 2728 4485 73 H(26B) 6275 2186 5180 73 H(26A) 5233 1404 4278 73 ______
201 APPENDIX K
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C13H19AgN4O6 (CHAPTER IV-2b)
Table 1. Crystal data and structure refinement for C13 H19 Ag N4 O6.
Identification code C13 H19 Ag N4 O6
Empirical formula C13 H19 Ag N4 O6 Formula weight 435.19 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 8.9319(10) Å a= 90.103(2)°. b = 9.0361(10) Å b= 101.168(2)°. c = 10.9601(13) Å g = 114.159(2)°. Volume 788.57(16) Å3 Z 2 Density (calculated) 1.833 Mg/m3 Absorption coefficient 1.318 mm-1 F(000) 440 Crystal size 0.34 x 0.34 x 0.22 mm3 Theta range for data collection 1.90 to 28.18°. Index ranges -11 £h £11, -11 £k £11, -14 £ l £14 Reflections collected 6767 Independent reflections 3539 [R(int) = 0.0174] Completeness to theta = 26.30° 98.8 % 202 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.7452 and 0.6496 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 3539 / 0 / 223 Goodness-of-fit on F2 1.110 Final R indices [I>2sigma(I)] R1 = 0.0298, wR2 = 0.0745 R indices (all data) R1 = 0.0309, wR2 = 0.0753 Largest diff. peak and hole 1.686 and -0.421 e.Å-3
203 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C13 H19 Ag N4 O6. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 10442(1) 11878(1) 632(1) 20(1) O(1) 15905(3) 9688(3) 3487(2) 31(1) O(2) 12709(3) 9057(3) 1775(2) 28(1) O(3) 5332(2) 4301(2) 3887(2) 26(1) O(4) 10826(2) 8036(2) 5294(2) 26(1) O(5) 11785(2) 13799(2) -385(2) 23(1) O(6) 9482(3) 14055(3) -1483(2) 32(1) N(1) 10308(3) 9754(3) 2875(2) 18(1) N(2) 7796(3) 8954(3) 1675(2) 18(1) N(3) 6280(3) 6526(3) 2761(2) 18(1) N(4) 8053(3) 6213(3) 4601(2) 19(1) C(1) 14993(3) 10693(3) 3477(3) 21(1) C(2) 13106(3) 9612(3) 3063(2) 19(1) C(3) 12153(3) 10630(3) 3348(3) 19(1) C(4) 9454(3) 10098(3) 1834(2) 19(1) C(5) 6462(3) 8964(4) 638(3) 25(1) C(6) 7661(3) 7888(3) 2598(2) 17(1) C(7) 9224(3) 8393(3) 3374(2) 18(1) C(8) 9506(3) 7605(3) 4491(2) 19(1) C(9) 8206(4) 5285(3) 5706(3) 25(1) C(10) 6475(3) 5594(3) 3758(2) 20(1) C(11) 4615(3) 5904(4) 1886(3) 28(1) C(12) 11037(3) 14544(3) -1098(2) 21(1) C(13) 12201(4) 16183(4) -1461(3) 29(1) ______
204 Table 3. Bond lengths [Å] and angles [°] for C13 H19 Ag N4 O6. ______Ag(1)-C(4) 2.096(3) Ag(1)-O(5) 2.1254(19) O(1)-C(1) 1.446(3) O(2)-C(2) 1.424(3) O(3)-C(10) 1.228(3) O(4)-C(8) 1.240(3) O(5)-C(12) 1.296(3) O(6)-C(12) 1.254(3) N(1)-C(4) 1.356(3) N(1)-C(7) 1.408(3) N(1)-C(3) 1.487(3) N(2)-C(6) 1.386(3) N(2)-C(4) 1.392(3) N(2)-C(5) 1.482(3) N(3)-C(6) 1.383(3) N(3)-C(10) 1.409(3) N(3)-C(11) 1.486(3) N(4)-C(10) 1.415(3) N(4)-C(8) 1.416(3) N(4)-C(9) 1.491(3) C(1)-C(2) 1.535(3) C(2)-C(3) 1.552(3) C(6)-C(7) 1.378(3) C(7)-C(8) 1.450(4) C(12)-C(13) 1.528(4)
C(4)-Ag(1)-O(5) 171.44(9) C(12)-O(5)-Ag(1) 121.12(17) C(4)-N(1)-C(7) 110.4(2) C(4)-N(1)-C(3) 123.8(2) C(7)-N(1)-C(3) 125.7(2) C(6)-N(2)-C(4) 109.7(2) C(6)-N(2)-C(5) 128.5(2) 205 C(4)-N(2)-C(5) 121.8(2) C(6)-N(3)-C(10) 118.8(2) C(6)-N(3)-C(11) 123.8(2) C(10)-N(3)-C(11) 117.3(2) C(10)-N(4)-C(8) 126.7(2) C(10)-N(4)-C(9) 116.5(2) C(8)-N(4)-C(9) 116.8(2) O(1)-C(1)-C(2) 108.9(2) O(2)-C(2)-C(1) 109.9(2) O(2)-C(2)-C(3) 112.6(2) C(1)-C(2)-C(3) 107.5(2) N(1)-C(3)-C(2) 112.2(2) N(1)-C(4)-N(2) 105.9(2) N(1)-C(4)-Ag(1) 127.34(18) N(2)-C(4)-Ag(1) 126.64(18) C(7)-C(6)-N(3) 123.1(2) C(7)-C(6)-N(2) 107.4(2) N(3)-C(6)-N(2) 129.4(2) C(6)-C(7)-N(1) 106.5(2) C(6)-C(7)-C(8) 121.9(2) N(1)-C(7)-C(8) 131.5(2) O(4)-C(8)-N(4) 121.0(2) O(4)-C(8)-C(7) 126.9(2) N(4)-C(8)-C(7) 112.1(2) O(3)-C(10)-N(3) 121.6(2) O(3)-C(10)-N(4) 121.5(2) N(3)-C(10)-N(4) 116.9(2) O(6)-C(12)-O(5) 126.1(3) O(6)-C(12)-C(13) 118.7(2) O(5)-C(12)-C(13) 115.1(2) ______Symmetry transformations used to generate equivalent atoms:
206 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C13 H19 Ag N4 O6. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 19(1) 21(1) 24(1) 8(1) 8(1) 9(1) O(1) 18(1) 33(1) 43(1) -8(1) 1(1) 12(1) O(2) 26(1) 29(1) 25(1) 3(1) 4(1) 9(1) O(3) 21(1) 20(1) 33(1) 6(1) 7(1) 5(1) O(4) 20(1) 28(1) 27(1) 6(1) 0(1) 9(1) O(5) 23(1) 22(1) 26(1) 6(1) 7(1) 10(1) O(6) 22(1) 30(1) 38(1) -4(1) -1(1) 7(1) N(1) 14(1) 17(1) 23(1) 4(1) 4(1) 7(1) N(2) 16(1) 20(1) 19(1) 4(1) 3(1) 10(1) N(3) 15(1) 18(1) 21(1) 3(1) 4(1) 6(1) N(4) 17(1) 18(1) 22(1) 6(1) 4(1) 8(1) C(1) 15(1) 22(1) 25(1) 2(1) 4(1) 8(1) C(2) 16(1) 19(1) 20(1) 2(1) 4(1) 7(1) C(3) 14(1) 17(1) 26(1) 4(1) 4(1) 6(1) C(4) 16(1) 19(1) 24(1) 2(1) 4(1) 10(1) C(5) 17(1) 31(1) 24(1) 10(1) 2(1) 9(1) C(6) 16(1) 17(1) 21(1) 1(1) 5(1) 8(1) C(7) 16(1) 15(1) 23(1) 2(1) 5(1) 6(1) C(8) 18(1) 18(1) 22(1) 2(1) 4(1) 9(1) C(9) 23(1) 25(1) 31(1) 13(1) 8(1) 12(1) C(10) 19(1) 18(1) 25(1) 3(1) 7(1) 10(1) C(11) 16(1) 29(1) 28(1) 6(1) -2(1) 2(1) C(12) 22(1) 21(1) 21(1) 0(1) 4(1) 9(1) C(13) 30(2) 27(1) 34(2) 11(1) 8(1) 14(1) ______
207 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C13 H19 Ag N4 O6. ______x y z U(eq) ______
H(1) 16937 10264 3743 47 H(2A) 11957 8101 1655 41 H(1A) 15347 11543 2894 25 H(1B) 15237 11237 4322 25 H(2) 12810 8648 3564 22 H(3A) 12389 10892 4262 23 H(3B) 12572 11669 2958 23 H(5A) 6016 7958 86 37 H(5B) 6932 9903 164 37 H(5C) 5556 9037 980 37 H(9A) 8840 4653 5580 38 H(9B) 7084 4545 5808 38 H(9C) 8796 6046 6456 38 H(11A) 4152 6719 1877 42 H(11B) 3851 4893 2160 42 H(11C) 4744 5690 1044 42 H(13A) 11651 16422 -2252 44 H(13B) 13249 16137 -1559 44 H(13C) 12449 17041 -807 44 ______
208 APPENDIX L
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C13H15AgN4O6 (CHAPTER IV-2c)
Table 1. Crystal data and structure refinement for C13 H15 Ag N4 O6.
Identification code C13 H15 Ag N4 O6
Empirical formula C13 H15 Ag N4 O6 Formula weight 433.18 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Triclinic Space group P-1 Unit cell dimensions a = 4.8968(9) Å a= 100.474(3)°. b = 10.5734(18) Å b= 92.729(3)°. c = 15.016(3) Å g = 98.084(3)°. Volume 754.8(2) Å3 Z 2 Density (calculated) 1.906 Mg/m3 Absorption coefficient 1.376 mm-1 F(000) 436 Crystal size 0.46 x 0.06 x 0.05 mm3 Theta range for data collection 1.38 to 28.29°. Index ranges -6£ h £6, -13£ k £ 14, -19£ l £19 Reflections collected 6612 Independent reflections 3482 [R(int) = 0.0255] Completeness to theta = 28.29° 92.5 % 209 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.9344 and 0.6301 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 3482 / 0 / 222 Goodness-of-fit on F2 1.156 Final R indices [I>2sigma(I)] R1 = 0.0424, wR2 = 0.1013 R indices (all data) R1 = 0.0452, wR2 = 0.1038 Largest diff. peak and hole 2.079 and -1.117 e.Å-3
210 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C13 H15 Ag N4 O6. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Ag(1) 13974(1) 553(1) 7502(1) 16(1) O(1) 10197(7) 1867(3) 10404(2) 25(1) O(2) 6912(6) 1464(3) 9247(2) 24(1) O(3) 3686(6) 5065(3) 6397(2) 27(1) O(4) 7302(6) 4724(3) 9189(2) 23(1) O(5) 16473(6) -925(3) 7494(2) 24(1) O(6) 16023(7) -1001(3) 6008(2) 25(1) N(1) 10465(7) 2698(3) 8185(2) 14(1) N(2) 10103(7) 2195(3) 6719(2) 16(1) N(3) 6869(7) 3692(3) 6420(2) 18(1) N(4) 5568(7) 4918(3) 7784(2) 20(1) C(1) 8457(10) 1051(4) 10898(3) 29(1) C(2) 9160(8) 1952(4) 9580(2) 17(1) C(3) 11306(8) 2738(4) 9134(2) 16(1) C(4) 11354(8) 1919(4) 7482(3) 16(1) C(5) 10486(9) 1481(4) 5803(3) 20(1) C(6) 8475(8) 3130(4) 6955(3) 16(1) C(7) 8648(8) 3444(4) 7875(2) 15(1) C(8) 7217(8) 4389(4) 8369(3) 19(1) C(9) 4113(10) 5967(4) 8211(3) 30(1) C(10) 5270(8) 4583(4) 6834(3) 20(1) C(11) 7088(10) 3571(4) 5441(3) 26(1) C(12) 16968(8) -1359(4) 6680(3) 18(1) C(13) 18896(9) -2370(4) 6564(3) 23(1) ______
211 Table 3. Bond lengths [Å] and angles [°] for C13 H15 Ag N4 O6. ______Ag(1)-C(4) 2.065(4) Ag(1)-O(5) 2.115(3) O(1)-C(2) 1.338(5) O(1)-C(1) 1.452(5) O(2)-C(2) 1.192(5) O(3)-C(10) 1.215(5) O(4)-C(8) 1.215(5) O(5)-C(12) 1.274(5) O(6)-C(12) 1.233(5) N(1)-C(4) 1.346(5) N(1)-C(7) 1.386(5) N(1)-C(3) 1.457(5) N(2)-C(6) 1.364(5) N(2)-C(4) 1.371(5) N(2)-C(5) 1.477(5) N(3)-C(6) 1.365(5) N(3)-C(10) 1.389(5) N(3)-C(11) 1.463(5) N(4)-C(10) 1.401(5) N(4)-C(8) 1.405(5) N(4)-C(9) 1.468(5) C(2)-C(3) 1.505(5) C(6)-C(7) 1.356(5) C(7)-C(8) 1.421(5) C(12)-C(13) 1.515(5)
C(4)-Ag(1)-O(5) 176.88(14) C(2)-O(1)-C(1) 116.1(4) C(12)-O(5)-Ag(1) 109.1(2) C(4)-N(1)-C(7) 110.4(3) C(4)-N(1)-C(3) 124.2(3) C(7)-N(1)-C(3) 125.4(3) C(6)-N(2)-C(4) 110.1(3) 212 C(6)-N(2)-C(5) 128.5(3) C(4)-N(2)-C(5) 121.3(3) C(6)-N(3)-C(10) 118.7(3) C(6)-N(3)-C(11) 123.0(3) C(10)-N(3)-C(11) 117.6(3) C(10)-N(4)-C(8) 126.5(3) C(10)-N(4)-C(9) 116.9(3) C(8)-N(4)-C(9) 116.5(4) O(2)-C(2)-O(1) 125.3(4) O(2)-C(2)-C(3) 125.6(3) O(1)-C(2)-C(3) 109.1(3) N(1)-C(3)-C(2) 111.6(3) N(1)-C(4)-N(2) 105.4(3) N(1)-C(4)-Ag(1) 128.9(3) N(2)-C(4)-Ag(1) 125.7(3) C(7)-C(6)-N(2) 107.5(3) C(7)-C(6)-N(3) 122.6(4) N(2)-C(6)-N(3) 129.9(4) C(6)-C(7)-N(1) 106.5(3) C(6)-C(7)-C(8) 123.6(4) N(1)-C(7)-C(8) 129.9(3) O(4)-C(8)-N(4) 121.8(4) O(4)-C(8)-C(7) 126.9(4) N(4)-C(8)-C(7) 111.3(3) O(3)-C(10)-N(3) 121.9(4) O(3)-C(10)-N(4) 120.8(4) N(3)-C(10)-N(4) 117.2(3) O(6)-C(12)-O(5) 124.5(4) O(6)-C(12)-C(13) 119.8(4) O(5)-C(12)-C(13) 115.6(3) ______Symmetry transformations used to generate equivalent atoms:
213 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C13 H15 Ag N4 O6. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Ag(1) 17(1) 16(1) 16(1) 3(1) 4(1) 9(1) O(1) 37(2) 26(2) 16(1) 8(1) 5(1) 9(1) O(2) 18(1) 29(2) 28(2) 8(1) 5(1) 6(1) O(3) 22(2) 27(2) 36(2) 13(1) -2(1) 8(1) O(4) 29(2) 24(1) 16(1) -4(1) 7(1) 9(1) O(5) 28(2) 28(2) 19(1) 4(1) 6(1) 16(1) O(6) 32(2) 26(2) 18(1) 4(1) 4(1) 11(1) N(1) 17(2) 14(1) 13(1) 2(1) 2(1) 7(1) N(2) 19(2) 15(1) 14(2) 1(1) 4(1) 6(1) N(3) 21(2) 20(2) 16(2) 6(1) 2(1) 7(1) N(4) 21(2) 17(2) 25(2) 3(1) 8(1) 11(1) C(1) 44(3) 28(2) 21(2) 10(2) 12(2) 12(2) C(2) 24(2) 16(2) 13(2) 2(1) 4(1) 11(2) C(3) 16(2) 22(2) 10(2) 0(1) 1(1) 6(1) C(4) 19(2) 13(2) 18(2) 2(1) 2(1) 4(1) C(5) 27(2) 22(2) 12(2) -1(2) 3(1) 10(2) C(6) 15(2) 16(2) 16(2) 5(1) 3(1) 3(1) C(7) 16(2) 14(2) 14(2) 1(1) 3(1) 5(1) C(8) 17(2) 16(2) 23(2) 3(2) 4(2) 5(1) C(9) 29(2) 25(2) 39(3) 5(2) 12(2) 17(2) C(10) 18(2) 17(2) 26(2) 7(2) 1(2) 3(2) C(11) 31(2) 29(2) 18(2) 6(2) -2(2) 8(2) C(12) 16(2) 17(2) 20(2) 4(2) 3(1) 3(1) C(13) 21(2) 22(2) 26(2) -3(2) 2(2) 7(2) ______
214 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C13 H15 Ag N4 O6. ______x y z U(eq) ______
H(1A) 6945 1502 11130 44 H(1B) 9563 868 11408 44 H(1C) 7688 231 10491 44 H(3A) 11613 3652 9464 19 H(3B) 13077 2392 9174 19 H(5A) 8688 1042 5508 30 H(5B) 11703 833 5855 30 H(5C) 11322 2094 5440 30 H(9A) 3732 5856 8830 44 H(9B) 2366 5936 7856 44 H(9C) 5270 6809 8234 44 H(11A) 9033 3775 5319 38 H(11B) 6021 4177 5211 38 H(11C) 6357 2678 5136 38 H(13A) 18138 -3086 6065 35 H(13B) 19080 -2706 7127 35 H(13C) 20717 -1971 6425 35 ______
215 APPENDIX M
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C19H30N4O3SRh, PF6 (CHAPTER V-1)
216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 APPENDIX N
SUPPLEMENTARY MATERIAL FOR THE X-RAY CRYSTAL STRUCTURE OF
C11H18Cl2N4O3PtS (CHAPTER V-2)
Table 1. Crystal data and structure refinement for C11H18Cl2N4O3PtS.
Identification code C11H18Cl2N4O3PtS Empirical formula C11 H18 Cl2 N4 O3 Pt S Formula weight 552.34 Temperature 100(2) K Wavelength 0.71073 Å Crystal system Monoclinic Space group P2(1)/m Unit cell dimensions a = 7.732(2) Å a= 90°. b = 8.645(2) Å b= 102.142(4)°. c = 11.701(3) Å g = 90°. Volume 764.6(3) Å3 Z 2 Density (calculated) 2.399 Mg/m3 Absorption coefficient 9.678 mm-1 F(000) 528 Crystal size 0.14 x 0.06 x 0.04 mm3 Theta range for data collection 1.78 to 28.24°. Index ranges -9 h 10, -11 k 11, -15 l 15 Reflections collected 6681 Independent reflections 1966 [R(int) = 0.0445] Completeness to theta = 28.24° 96.9 % 233 Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.6982 and 0.1326 Refinement method Full-matrix least-squares on F2 Data / restraints / parameters 1966 / 81 / 127 Goodness-of-fit on F2 1.103 Final R indices [I>2sigma(I)] R1 = 0.0361, wR2 = 0.0765 R indices (all data) R1 = 0.0500, wR2 = 0.0818 Largest diff. peak and hole 2.507 and -1.257 e.Å-3
234 Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
ij for C11H18Cl2N4O3PtS. U(eq) is defined as one third of the trace of the orthogonalized U tensor. ______x y z U(eq) ______Pt 8297(1) 2500 4197(1) 18(1) Cl(1) 6130(3) 2500 5256(2) 30(1) Cl(2) 10464(3) 2500 5876(2) 23(1) S 10309(3) 2500 3158(2) 19(1) O(1) 740(40) 970(30) -950(20) 38(6) O(2) 3250(20) -353(18) 449(16) 33(3) O(3) 9702(8) 2500 1912(5) 32(2) N(1) 5620(6) 1266(7) 2274(4) 26(1) N(2) 3168(7) 841(9) 559(5) 28(1) N(3) 1977(7) 1748(9) -234(5) 35(2) C(1) 6444(10) 2500 2815(7) 24(2) C(2) 6070(8) -301(8) 2648(6) 32(2) C(3) 4322(7) 1737(9) 1360(5) 28(1) C(4) 2990(30) -920(20) 570(20) 33(5) C(5) 1977(7) 1748(9) -234(5) 35(2) C(8) 11716(9) 930(8) 3543(7) 34(2) C(7) 3168(7) 841(9) 559(5) 28(1) C(6) 870(50) 930(70) -1070(40) 45(8) ______
235 Table 3. Bond lengths [Å] and angles [°] for C11H18Cl2N4O3PtS. ______Pt-C(1) 1.922(8) Pt-S 2.167(2) Pt-Cl(1) 2.284(2) Pt-Cl(2) 2.298(2) S-O(3) 1.435(6) S-C(8)#1 1.739(7) S-C(8) 1.739(7) N(1)-C(1) 1.332(7) N(1)-C(3) 1.366(8) N(1)-C(2) 1.444(9) N(2)-C(3) 1.387(9) N(2)-C(4) 1.532(19) N(3)-N(3)#1 1.300(15) N(3)-C(6) 1.36(4) C(1)-N(1)#1 1.332(7) C(3)-C(3)#1 1.319(15) C(1)-Pt-S 91.4(2) C(1)-Pt-Cl(1) 87.4(2) S-Pt-Cl(1) 178.76(8) C(1)-Pt-Cl(2) 178.7(2) S-Pt-Cl(2) 89.97(8) Cl(1)-Pt-Cl(2) 91.28(8) O(3)-S-C(8)#1 108.4(3) O(3)-S-C(8) 108.4(3) C(8)#1-S-C(8) 102.7(5) O(3)-S-Pt 116.8(3) C(8)#1-S-Pt 109.8(2) C(8)-S-Pt 109.8(2) C(1)-N(1)-C(3) 109.4(6) C(1)-N(1)-C(2) 123.2(5) C(3)-N(1)-C(2) 127.4(6) C(3)-N(2)-C(4) 126.6(11) N(3)#1-N(3)-C(6) 122(2) 236 N(1)-C(1)-N(1)#1 106.4(7) N(1)-C(1)-Pt 126.7(4) N(1)#1-C(1)-Pt 126.7(4) C(3)#1-C(3)-N(1) 107.3(4) C(3)#1-C(3)-N(2) 124.0(4) N(1)-C(3)-N(2) 128.7(7) ______Symmetry transformations used to generate equivalent atoms: #1 x,-y+1/2,z
237 2 3 Table 4. Anisotropic displacement parameters (Å x 10 ) for C11H18Cl2N4O3PtS. The anisotropic displacement factor exponent takes the form: -2p2[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______U11 U22 U33 U23 U13 U12 ______Pt 9(1) 29(1) 16(1) 0 2(1) 0 Cl(1) 15(1) 50(2) 26(1) 0 9(1) 0 Cl(2) 15(1) 32(1) 21(1) 0 0(1) 0 S 16(1) 22(1) 21(1) 0 7(1) 0 O(1) 33(9) 57(11) 27(9) -31(8) 12(6) -32(8) O(2) 24(7) 36(6) 34(6) -17(7) -1(5) -14(6) O(3) 30(3) 48(4) 16(3) 0 4(3) 0 N(1) 13(2) 45(4) 19(3) -1(2) 2(2) 11(2) N(2) 17(3) 43(4) 23(3) -12(3) 0(2) 1(3) N(3) 18(3) 71(4) 17(3) -4(3) 5(2) 7(3) C(1) 13(4) 43(6) 15(4) 0 2(3) 0 C(2) 22(3) 35(4) 35(4) -10(3) 1(3) 9(3) C(3) 14(3) 48(4) 22(3) -2(3) 6(2) 3(3) C(4) 10(7) 38(9) 48(12) -29(11) -4(6) -6(8) C(5) 18(3) 71(4) 17(3) -4(3) 5(2) 7(3) C(8) 29(3) 30(4) 50(4) 10(3) 26(3) 12(3) C(7) 17(3) 43(4) 23(3) -12(3) 0(2) 1(3) C(6) 14(9) 90(20) 27(11) -3(11) 4(7) -6(10) ______
238 Table 5. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 10 3) for C11H18Cl2N4O3PtS. ______x y z U(eq) ______
H(2A) 7057 -289 3328 47 H(2B) 6414 -878 2010 47 H(2C) 5043 -800 2860 47 H(4A) 3933 -1357 1181 50 H(4B) 3097 -1340 -192 50 H(4C) 1838 -1205 728 50 H(8A) 12623 935 3071 50 H(8B) 11033 -32 3402 50 H(8C) 12284 1001 4373 50 H(6A) 86 1635 -1588 67 H(6B) 161 223 -695 67 H(6C) 1566 324 -1521 67 ______
239 APPENDIX O
INSTITUTIONAL ANIMAL CARE AND USE COMMITTEE (IACUC), ANIMAL
STUDIES PROTOCOL APPROVAL
240 241 242 243 244 245