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The Preparation and Reactions of Certain Quarternary Ammonium And
THE PREPARATION AND REACTIONS OF CERTAIN QUATERNARY AMMONIUM AND RELATED COMPOUNDS By CARL L MICHAELIS A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA August, 1953 ACKNOWLEDGMENTS The author wishes to express his sincere appreci- ation for the valuable assistance and inspiring direction of Dr. George B. Butler. Special thanks are due Dr. and Mrs. Armin Gropp for the help and encouragement in carrying out this investi- gation. The author also wishes to express his appreciation for the assistance and advice so readily given him by his fellow students, graduate and undergraduate alike. \ ii TABLE OF CONTENTS Page ACKNOWLEDGMENTS ii TABLE OF CONTENTS iii INTRODUCTION 1 A. Review of Literature and Statement of Problem 1 EXPERIMENTAL 14 A. General Discussion 14 B. Procedure 18 DISCUSSION . 51 SUMMARY 62 BIBLIOGRAPHY 64 BIOGRAPHICAL ITEMS 66 COMMITTEE REPORT 67 iii INTRODUCTION The need for compounds of good adrenergic blooking activity has been the object of extensive investigation in recent years. In order to get a better idea of the nature of adrenergic blocking activity, it might be best to under- stand first how an adrenergic compound functions. Certain compounds like epinephrine or adrenaline, are powerful agents in stimulating the sympathetic nervous system, that part of the nervous system springing from the thoracic lumbar cord. The substance epinephrine is much like, if not identical to, the substance called sympathin, which is produced at the ending of a nerve in the smooth muscle or gland when a nerve is stimulated. -
Designing Peptidomimetics
CORE Metadata, citation and similar papers at core.ac.uk Provided by UPCommons. Portal del coneixement obert de la UPC DESIGNING PEPTIDOMIMETICS Juan J. Perez Dept. of Chemical Engineering ETS d’Enginyeria Industrial Av. Diagonal, 647 08028 Barcelona, Spain 1 Abstract The concept of a peptidomimetic was coined about forty years ago. Since then, an enormous effort and interest has been devoted to mimic the properties of peptides with small molecules or pseudopeptides. The present report aims to review different approaches described in the past to succeed in this goal. Basically, there are two different approaches to design peptidomimetics: a medicinal chemistry approach, where parts of the peptide are successively replaced by non-peptide moieties until getting a non-peptide molecule and a biophysical approach, where a hypothesis of the bioactive form of the peptide is sketched and peptidomimetics are designed based on hanging the appropriate chemical moieties on diverse scaffolds. Although both approaches have been used in the past, the former has been more widely used to design peptidomimetics of secretory peptides, whereas the latter is nowadays getting momentum with the recent interest in designing protein-protein interaction inhibitors. The present report summarizes the relevance of the information gathered from structure-activity studies, together with a short review on the strategies used to design new peptide analogs and surrogates. In a following section there is a short discussion on the characterization of the bioactive conformation of a peptide, to continue describing the process of designing conformationally constrained analogs producing first and second generation peptidomimetics. Finally, there is a section devoted to review the use of organic scaffolds to design peptidomimetics based on the information available on the bioactive conformation of the peptide. -
Molecular Genetic Approaches to Decrease Mis-Incorporation of Non
Molecular genetic approaches to decrease mis-incorporation of non-canonical branched chain amino acids into a recombinant protein in Escherichia coli Ángel Córcoles García Molecular genetic approaches to decrease mis- incorporation of non-canonical branched chain amino acids into a recombinant protein in Escherichia coli Ángel Córcoles García - Dissertation Abstract II Molecular genetic approaches to decrease mis-incorporation of non-canonical branched chain amino acids into a recombinant protein in Escherichia coli vorgelegt von M. Sc. Ángel Córcoles García ORCID: 0000-0001-9300-5780 von der Fakultät III-Prozesswissenschaften der Technischen Universität Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften - Dr. rer. nat. - genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr. Juri Rappsilber, Institut für Biotechnologie, TU Berlin, Berlin Gutachter: Prof. Dr. Peter Neubauer, Institut für Biotechnologie, TU Berlin, Berlin Gutachter: Prof. Dr. Pau Ferrer, Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Spain Gutachter: Dr. Heinrich Decker, Sanofi-Aventis Deutschland GmbH, Frankfurt am Main Tag der wissenschaftlichen Aussprache: 11. Dezember 2019 Berlin 2020 Molecular genetic approaches to decrease mis-incorporation of non-canonical branched chain amino acids into a recombinant protein in Escherichia coli Ángel Córcoles García Abstract The incorporation of non-canonical branched chain amino acids (ncBCAA) such as norleucine, norvaline and β-methylnorleucine into recombinant proteins during E.coli production processes has become a crucial matter of contention in the pharmaceutical industry, since such mis-incorporation can lead to production of altered proteins, having non optimal characteristics. Hence, a need exists for novel strategies valuable for preventing the mis-incorporation of ncBCAA into recombinant proteins. This work presents the development of novel E. -
Polyketide Synthase Gene Coupled to the Peptide Synthetase Module Involved in the Biosynthesis of the Cyclic Heptapeptide Microcystinl
J. Biochem. 127, 779-789(2000) Polyketide Synthase Gene Coupled to the Peptide Synthetase Module Involved in the Biosynthesis of the Cyclic Heptapeptide Microcystinl Tomoyasu Nishizawa, Akiko Ueda, Munehiko Asayama,* Kiyonaga Fujii,•õ Ken-ichi Harada,i Kozo Ochi,•ö and Makoto Shirai*,•˜,2 * Division of Biotechnology, School ofAgriculture, Ibaraki University Ami , Ibaraki 300-0393; •õFaculty of Pharmacy, M eija University, Tempaku , Nagoya 468-8503, •öNational Food Research Institute, Tsukuba, Ibaraki 305-8642; and •˜ Gene Research Center, Ibaraki University, Ann, Ibaraki 300-0393 Received January 17, 2000; accepted February 11, 2000 The peptide synthetase gene operon, which consists of encyA, mcyB, and mcyC, for the activation and incorporation of the five amino acid constituents of microcystin has been identified [T. Nishizawa et al. (1999) J. Biochem. 126, 520-529] . By sequencing an addi tional 34 kb of DNA from microcystin-producing Microcystis aeruginosa K-139 , we identifi ed the residual microcystin synthetase gene operon, which consists of mcyD, mcyE, meyF, and mcyG, in the opposite orientation to the mcyABC operon. McyD consisted of two polyketide synthase modules, and McyE contained a polyketide synthase module at the N-terminus and a peptide synthetase module at the C-terminus. McyF was found to exhibit similarity to amino acid racemase. McyG consisted of a peptide synthetase mod ule at the N-terminus and a polyketide synthase at the C-terminus. The microcystin syn thetase gene cluster was conserved in another microcystin-producing strain, Microcystis sp. S-70, which produces Microcystin-LR, -RR, and -YR. Insertional mutagenesis of mcyA, mcyD, or meyE in Microcystis sp. -
5 Water, the Spring of Life
5 Water, the Spring of Life André Brack Primitive life probably appeared with the first chemical systems able to transfer their molecular information via self-reproduction and also to evolve. By analogy with con- temporary life, it is generally believed that life on Earth emerged in liquid water from the processing of organic molecules. Schematically, the premises of primitive life can be compared to parts of "chemical robots". By chance, some parts self-assembled to generate robots capable of assembling other parts to form identical robots. Sometimes, a minor error in the building generated more efficient robots, which became the domi- nant species. The number of parts required for the first robots as well as the nature of these chemical robots are still unknown. The traces of the primitive chemical robots have been probably erased for ever on Earth by the combined action of plate tectonics, the permanent presence of liquid water, the unshielded solar ultraviolet radiation and atmospheric oxygen. Despite its harmful ability to erase fossils, liquid water exhibits interesting peculiarities, which contributed to the birth of life on Earth. It is therefore generally considered as a prerequisite for terrestrial-type life to appear on a planet. Some possible contributions of water to the origin of life are presented here. 5.1 Water as a Diffusion Milieu Assembling parts of the primitive molecular robots must have occurred at a reasonable rate. Solid state life is generally discarded, the parts being unable to migrate and to be easily exchanged. A gaseous phase would allow fast diffusion of the parts, but the limited inventory of stable volatile organic molecules would constitute a severe re- striction. -
Interrupted Adenylation Domains: Unique Bifunctional Enzymes Involved in Nonribosomal Peptide Biosynthesis
Natural Product Reports Interrupted adenylation domains: unique bifunctional enzymes involved in nonribosomal peptide biosynthesis Journal: Natural Product Reports Manuscript ID: NP-REV-09-2014-000120.R1 Article Type: Highlight Date Submitted by the Author: 12-Jan-2015 Complete List of Authors: Labby, Kristin; Beloit College, Chemistry Watsula, Stoyan; University of Michigan, Medicinal Chemistry Garneau-Tsodikova, Sylvie; University of Kentucky, Pharmaceutical Sciences Page 1 of 11NPR Natural Product Reports Dynamic Article Links ► Cite this: DOI: 10.1039/c0xx00000x www.rsc.org/xxxxxx HIGHLIGHT Interrupted adenylation domains: unique bifunctional enzymes involved in nonribosomal peptide biosynthesis Kristin J. Labby, a Stoyan G. Watsula,b and Sylvie Garneau-Tsodikova* c Received (in XXX, XXX) Xth XXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX 5 DOI: 10.1039/b000000x Covering up to 2014 Nonribosomal peptides (NRPs) account for a large portion of drugs and drug leads currently available in the pharmaceutical industry. They are one of two main families of natural products biosynthesized on megaenzyme assembly-lines composed of multiple modules that are, in general, each comprised of three 10 core domains and on occasion of accompanying auxiliary domains. The core adenylation (A) domains are known to delineate the identity of the specific chemical components to be incorporated into the growing NRPs. Previously believed to be inactive, A domains interrupted by auxiliary enzymes have recently been proven to be active and capable of performing two distinct chemical reactions. This highlight summarizes current knowledge on A domains and presents the various interrupted A domains found in a number of 15 nonribosomal peptide synthetase (NRPS) assembly-lines, their predicted or proven dual functions, and their potential for manipulation and engineering for chemoenzymatic synthesis of new pharmaceutical agents with increased potency. -
Stability Toward High Energy Radiation of Non-Proteinogenic Amino Acids: Implications for the Origins of Life
Life 2013, 3, 449-473; doi:10.3390/life3030449 OPEN ACCESS life ISSN 2075-1729 www.mdpi.com/journal/life Article Stability toward High Energy Radiation of Non-Proteinogenic Amino Acids: Implications for the Origins of Life Franco Cataldo 1,2,*, Susana Iglesias-Groth 3, Giancarlo Angelini 4 and Yaser Hafez 5 1 Actinium Chemical Research srl, Via Casilina 1626A, Rome 00133, Italy 2 Astrophysical Observatory of Catania, Via S. Sofia 78, Catania 95123, Italy 3 Astrophysical Institute of Canary Islands, Via Lactea s/n, La Laguna 38200, Tenerife, Spain; E-Mail: [email protected] 4 Institute of Chemical Methodologies, CNR, Via Salaria Km 29,300, Monterotondo Stazione, Rome 00016, Italy; E-Mail: [email protected] 5 National Center for Astronomy, KACST, P.O. Box 6086, Riyad 11442, Saudi Arabia; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +39-06-9439-8230; Fax: +39-06-205-3393. Received: 8 May 2013; in revised form: 15 May 2013 / Accepted: 10 July 2013 / Published: 30 July 2013 Abstract: A series of non-proteinogenic amino acids, most of them found quite commonly in the meteorites known as carbonaceous chondrites, were subjected to solid state radiolysis in vacuum to a total radiation dose of 3.2 MGy corresponding to 23% of the total dose expected to be taken by organic molecules buried in asteroids and meteorites since the beginning of the solar system 4.6 × 109 years ago. The radiolyzed amino acids were studied by FT-IR spectroscopy, Differential Scanning Calorimetry (DSC) and by polarimety and Optical Rotatory Dispersion (ORD). -
Important Features of the Potential Energy Surface of the Methylamine Plus O(1D) Reaction
Physical Chemistry Chemical Physics Important Features of the Potential Energy Surface of the Methylamine Plus O(1D) Reaction Journal: Physical Chemistry Chemical Physics Manuscript ID CP-ART-09-2019-005039.R1 Article Type: Paper Date Submitted by the 17-Oct-2019 Author: Complete List of Authors: Wolf, Mark; University of Georgia , Center for Computational Quantum Chemsitry; Hoobler, Preston; Covenant College, Chemistry; University of Georgia Franklin College of Arts and Sciences, Center for Computational Quantum Chemistry Turney, Justin; University of Georgia, Center for Computational Chemistry Schaefer, Henry; University of Georgia, Computational Chemistry Page 1 of 13 Physical Chemistry Chemical Physics Journal Name Important Features of the Potential Energy Surface of the Methy- lamine Plus O(1D) Reaction † Mark E. Wolf, Preston R. Hoobler, Justin M. Turney, and Henry F. Schaefer III∗ This research presents an ab initio characterization of the potential energy surface for the methy- lamine plus 1D oxygen atom reaction, which may be relevant to interstellar chemistry. Ge- ometries and harmonic vibrational frequencies were determined for all stationary points at the CCSD(T)/aug-cc-pVTZ level of theory. The focal point method along with several additive correc- tions was used to obtain reliable CCSDT(Q)/CBS potential energy surface features. Extensive conformational analysis and intrinsic reaction coordinate computations were performed to ensure accurate chemical connectivity of the stationary points. Five minima were determined to be pos- sible products of this reaction and three novel transition states were found that were previously unreported or mislabeled in the literature. The pathways we present can be used to guide further searches for NH2 containing species in the interstellar medium. -
Is the Reaction Between Formic Acid and Protonated Aminomethanol a Possible Source of Glycine Precursors in the Interstellar Medium?
A&A 579, A125 (2015) Astronomy DOI: 10.1051/0004-6361/201526548 & c ESO 2015 Astrophysics Is the reaction between formic acid and protonated aminomethanol a possible source of glycine precursors in the interstellar medium? Pilar Redondo, Antonio Largo, and Carmen Barrientos Computational Chemistry Group, Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, 47011 Valladolid, Spain e-mail: [predondo;alargo;cbb]@qf.uva.es Received 18 May 2015 / Accepted 28 May 2015 ABSTRACT Context. One of the most interesting questions in interstellar chemistry concerns whether we can detect the basic building blocks of proteins in astronomical sources. In ascertaining whether amino acids could be possible interstellar molecules, a crucial point is how they could be synthesized in the interstellar medium. Aims. We do a theoretical study of the ion-molecule reaction involving protonated aminomethanol and formic acid to establish its viability in space. This ion-molecule reaction has been proposed by other authors as a possible way to produce glycine in the interstellar medium. Methods. The relevant stationary points on the potential energy surface of the reaction between protonated aminomethanol and formic acid have been theoretically studied by using ab initio methods. The second-order Moller-Plesset level was employed, in conjunction with the correlation-consistent polarized valence triple-zeta (cc-pVTZ) basis set. In addition, the electronic energies were refined by means of single-point calculations at the CCSD(T) level (coupled cluster single and double excitation model augmented with a non-iterative treatment of triple excitations) on the MP2/cc-pVTZ geometries with the aug-cc-pVTZ basis set. -
Structural Characterization of Microcystins by LC/MS/MS Under
J. Antibiot. 59(11): 710–719, 2006 THE JOURNAL OF ORIGINAL ARTICLE ANTIBIOTICS Structural Characterization of Microcystins by LC/MS/MS under Ion Trap Conditions Tsuyoshi Mayumi, Hajime Kato, Susumu Imanishi, Yoshito Kawasaki, Masateru Hasegawa, Ken-ichi Harada This article is dedicated in memory of Professor Kenneth L. Rinehart at the University of Illinois Received: May 16, 2006 / Accepted: November 2, 2006 © Japan Antibiotics Research Association Abstract LC/MS/MS under ion trap conditions was used cyclic peptide antibiotics such as bacitracin [1], colistin [2], to analyze microcystins produced by cyanobacteria. vancomycin [3] and micafungin [4], are widely used for Tandem mass spectrometry using MS2 was quite effective medical treatments. Moreover, cyclosporin [5] is an since ions arising from cleavage at a peptide bond provide immunosuppressive agent, which has been used for organ useful sequence information. The fragmentation was transplant rejection or bone marrow [6]. confirmed by a shifting technique using structurally-related For the structure determination of cyclic peptides, the microcystins and the resulting fragmentation pattern was following information is required: structures, absolute different from those determined by triple stage MS/MS and configurations and sequence of constituent amino acids. four sector MS/MS. Analysis of a mixture of microcystins Although partial acid hydrolysis had been used for the in a bloom sample was successfully performed and two structure determination of these cyclic peptides, it has been new microcystins were identified by LC/MS/MS under ion currently performed by instrumental methods such as 2D- trap conditions. Thus, LC/MS/MS under ion trap NMR (two dimensional nuclear magnetic resonance) and conditions is effective for the structural characterization of MS/MS (tandem mass spectrometry) techniques. -
Reaction of Several Aminopyrimidines with Formaldehyde Gerald L
JOURNAL OF RESEARCH of the National Bureau of Standards—A. Physics and Chemistry Vol. 66A, No. 1, January-February 1962 Reaction of Several Aminopyrimidines With Formaldehyde Gerald L. McLeod x (August 29, 1961) Formaldehyde has been shown to react with 2-aminopyrimidine (II) and 2-(methyl- amino)pyrimidine (V) at room temperature to give the corresponding methylol derivatives or the corresponding methylenebis(aminopyrimidines). The reaction of formaldehyde with 2-amino-4,6-dichloro-5-methylpyrimidine (VII) and also its failure to react with 2-(dimethylamino)pyrimidine (IX) are cited as evidence that the pyrimidine ring is not involved in the reaction. 1. Introduction methylol structure is supported by infrared analysis. The spectrum of 2-aminopyrimidine has two absorp- A number of investigations have been made on the tion bands near 3,320 and 3,170 cm"11 whichih are melamine-formaldehyde reaction, and several mech- 2 attributed to N—H asymmetric and symmetriy c anisms [1-5] have been suggested. The complex stretching modes [9]; the methylol compoundd, IIIIII, structures of the triamino-l,3,5-triazines made it shows one fairly broad band at 3,225 cm"1. The desirable to study simpler model compounds. A occurrence of both inter- and intra-molecular hydro- logical model compound, 2-amino-l,3,5~triazine (la), gen bonding in III could cause a lowering of the OH has been reported [6-8] not to give the usual amine stretching frequency, allowing it to overlap the reactions because it tautomerizes to the iminoid N—H stretching band. Treatment of the methylol structure (Ib). -
Microcystin-LR Toxicodynamics, Induced Pathology, and Immunohistochemical Localization in Livers of Blue-Green Algae Exposed Rainbow Trout (Oncorhynchus Mykiss)
Microcystin-LR Toxicodynamics, Induced Pathology, and Immunohistochemical Localization in Livers of Blue-Green Algae Exposed Rainbow Trout (Oncorhynchus mykiss) W. J. Fischer,* B. C. Hitzfeld,* F. Tencalla,† J. E. Eriksson,‡ A. Mikhailov,‡ and D. R. Dietrich*,1 *Environmental Toxicology, University of Konstanz, Konstanz, Germany; †Institute of Toxicology, Schwerzenbach, Switzerland; and ‡Turku Centre for Biotechnology, Turku, Finland Received June 29, 1999; accepted September 27, 1999 Microcystins (MC) constitute a family of toxins that are With this retrospective study, we investigated the temporal produced by several cyanobacterial taxa. These cyclic hep- pattern of toxin exposure and pathology, as well as the topical tapeptide molecules contain both L- and D-amino acids and an relationship between hepatotoxic injury and localization of micro- unusual hydrophobic C D-amino acid commonly termed cystin-LR, a potent hepatotoxin, tumor promoter, and inhibitor of 20 protein phosphatases-1 and -2A (PP), in livers of MC-gavaged ADDA (3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca- rainbow trout (Oncorhynchus mykiss) yearlings, using an immu- 4,6-dienoic acid). In most of the more-than-60 presently known nohistochemical detection method and MC-specific antibodies. toxin congeners, the 5 D-amino acid components are main- H&E stains of liver sections were used to determine pathological tained while the two L-amino acids are variable (Botes et al., changes. Nuclear morphology of hepatocytes and ISEL analysis 1985). Microcystin-LR, containing L-Leu and L-Arg, is one of were employed as endpoints to detect the advent of apoptotic cell the most commonly occurring (Watanabe et al., 1996) and at death in hepatocytes.