DOCSLIB.ORG

Acid-Catalysed Hydroaminations

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Acid-Catalysed Hydroaminations Acid-Catalysed Hydroaminations A thesis submitted to Cardiff University by Laura Henderson MChem (Hons.) In candidature of the degree of Doctor of Philosophy School of Chemistry Cardiff University UMI Number: U557419 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. Dissertation Publishing UMI U557419 Published by ProQuest LLC 2013. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 Acknowledgments First of all I would like to thank Prof. David W. Knight, for all his support, great ideas and seemingly endless breadth of knowledge that made this project possible. Secondly, I would also like to thank Dr. Andrew C. Williams for all the support and advice he has given over the last three years. I am grateful to the many students whose have contributed towards this thesis; they were all a joy to work with. In particular, I want to thank Nena Christiansen, Jon Williams and Rhian Courtney for their work. I want to thank Dr Rob Jenkins, Robin Hicks and Dave Walker for all of their mass spec, and NMR support over the years. I also want to thank Dr John Brazier and Dr Jacky Yau for all the advice and help that they gave, and endless enthusiasm that they have shown. My time at Cardiff has been very enjoyable, mostly due to the wonderful people that work here. They have truly made coming to work every day a pleasure. Thank you very much to everyone in the playroom and in particular members of the Knight group: Andrew, Andy, Damian, Ian and Jess, for making the last three years fun. I would like to thank the EPSRC and Eli Lilly for the financial support and everyone at Eli Lilly who made my placement a highly enjoyable experience. And finally, I am incredibly grateful to the endless support and encouragement that my parents, Alan and Margaret, and my sister, Gemma, have given me. DECLARATION This work has not previously been accepted in substance for any degree and is not concurrently submitted in candidature for any degree. Signed . .0 7 ^ ^ 7 7 7 . ..... .................................. .. (candidate) Date ..S t.'/S C p . ...2 r Q .\?P STATEMENT 1 This thesis is being submitted in partial fulfilment of the requirements for the degree of PhD Signed . j0f7!rr77rr7 ... .v^~77rrr:. ................. (candidate) Date . .2 .0 1 0 STATEMENT 2 This thesis is the result of my own independent work/investigation, except where otherwise stated. Other sources are acknowledged by explicit references. (candidate) Date. STATEMENT 3 I hereby give consent for my thesis, if accepted, to be available for photocopying and for inter- library loan, and for the title and summary to be made available to outside organisations. Signed ... (candidate) Date Abstract The Knight group has for some time been utilising the acid-catalysed hydroamination to synthesise pyrrolidines 140. This method was also utilised to produce poly-cyclic systems, of either a spiro- 220 or a fused-nature 12, through cascade reactions using a sulfonamide as a terminator. This was examined further to establish some scope and limitation. In particular, we have shown that the reaction is not limited to the formation of tertiary carbenium ions but could be implemented for cyclisations via secondary carbenium ions 155. The hydroamination was also shown to be most successful at forming highly hindered, bridged compounds 194, which would be difficult to synthesise through other means. The hydroamination reaction was then investigated in terms of its potential as a variant of the classical Pictet-Spengler reaction towards dihydroisoindoles 363 and tetrahydroisoquinolines 361. This was briefly explored in terms of the type of remote functional groups that would be compatible with this method. The formation of the isoindoles and isoquinolines was successful and further investigations of compatible functional groups need to be performed. The synthesis of the trisubstituted piperidine 447 was attempted using the acid-catalysed hydroamination method, believing that this would be a simple extension of the pyrrolidine synthesis. Unfortunately, this was not successful; instead the corresponding pyrrolidine 449 was isolated. This led us to further investigate the sensitivity of sterically crowded piperidines towards acid. Successful synthesis of trisubstituted piperidine 501 was achieved by changing the JV-protecting group. Contents Chapter 1 - Introduction to Acid-Catalysed Hydroaminations 1 1.1 Hydroamination Development 2 1.2 Bronsted Acid-Catalyzed Hydroamination of Alkenes and Alkynes 3 1.2.1. Intermolecular Bronsted Acid-Catalyzed Hydroamination of Alkenes 3 1.2.2. Intramolecular Bronsted Acid-Catalyzed Hydroamination of Alkenes 5 1.3. Development of Acid-Catalysed Hydroamination in the Knight Group 7 1.4. Conclusion 10 Chapter 2 - Acid-Catalysed Hydroaminations - Model Studies 11 2.1. Introduction 12 2.1.1. Intermolecular Methods for Pyrrolidine Formation 12 2.1.2. Intramolecular Methods to Afford Pyrrolidines 17 2.1.3. Reaction of Amino Alkenes 21 2.2. Background to Current Work 25 2.3. Results and Discussion 26 2.3.1. Simple Pyrrolidines 26 2.3.2. Terminal Double Bonds - Secondary vs. Primary Carbenium Ions 30 2.3.3. Investigations into Ring Opening and Re-closure 34 2.3.3.1. Investigations of the Mechanism 39 2.3.4. Transannular Cyclisations 40 2.3.5. Cascade & Fused Systems 42 2.3.6. Indene 44 2.3.7. O-N Compounds 47 2.3.7.1. Isoxazolidine vs. Morpholine 47 2.3.12. Transannular Cyclisations 53 2.3.7.3. 5^z>o-Isoxazolidines 54 2.4. Conclusion 57 Chapter 3 - A Hydroamination Variant of the Pictet-Spengler Reaction 58 3.1. Introduction 59 3.1.1 Development of the Pictet-Spengler Reaction 59 3.1.2. Tetrahydroisoquinolines 59 3.1.3. Pictet-Spengler Reaction of Indoles 64 3.1.4. Conclusion 67 3.2. Hypothesis 69 3.3. Results and Discussion 70 3.3.1. Proposed Synthetic Route 70 3.3.2. Suzuki Reaction 71 3.3.3. Cyclisations 74 3.3.3.1. Dihydroisoindoles 74 3.3.3.2. Tetrahydroisoquinolines 79 3.4. Remote Functional Groups 83 3.4.1. Alternatives to Suzuki 84 3.5. Conclusion 90 Chapter 4 - Ring-Contraction of Piperidines 93 4.1. Introduction 94 4.2. Results and Discussion 99 4.2.1. Ring-Contraction of Piperidines 99 4.2.2. Synthesis towards Piperidines 110 4.3. Conclusion 115 Chapter 6 - Experimental 117 6.1. General Details 118 6.2. General Procedures 119 6.3. Experimental Data 120 References 206 Appendix 220 Abbreviations Abbreviations in this text are: Ac Acetyl APCI Atmospheric Pressure Chemical Ionisation Aq. Aqueous Ar Aromatic Boc Butoxycarbonyl 9-BBN 9-Borabicyclo[3.3.1]nonane Cone. Concentrated Cbz Benxyl carbamate DBU 1,8-Diazobicyclo[5.4.0]undec-7-ene DCM Dichloromethane d.e. Diastereomeric excess DIAD Diisopropyl azodicarboxylate DMAP Dimethylaminopyridine DMF A^A-Dimethylformamide dtbpf Di-fer/-butyl phosphine ferrocene e.e. Enantiomeric excess Eq. Equivalents El Electro Ionisation ES Electro Spray hr Hour hrs Hours HRMS High Resolution Mass Spectrometry IR Infra red LDA Lithium diisopropylamine LRMS Low Resolution Mass Spectrometry m.p. Melting point M Molar (moles L'1) mins Minutes MsCl Mesyl chloride/ methanesulfonyl chloride NMR Nuclear Magnetic Resonance Ns / nosyl para-N itrobenzenesulfonyl z-Pr fro-Propyl Ppm Parts per million Py Pyridine r.t. Room temperature Sat. Saturated TBAF tetra-H-Butylammonium fluoride TBS tert-Butylsilyl THF Tetrahydrofiiran TLC Thin Layer Chromatography TfOH Trifluoromethane sulfonic acid PCy3 Tricyclohexylphosphine TsNHBoc iV-(fer/-Butoxycarbonyl)-/?-toluenesulfonamide Ts / tosyl p -T oluenesulfonyl TsCl p-T oluenesulfonyl chloride Chapter 1 1 Chapter 1 Introduction to Acid-Catalysed Hydroamination “Hydroamination is a highly atom-economical process in which an amine N-Hfunctionality is added to an unsaturated carbon-carbon linkage."1 1.1. Hydroamination Development Nitrogen-containing saturated heterocyclic systems are important core structures in organic chemistry because of their presence in many natural products; making the development of simple procedures for the formation of heterocycles, such as pyrrolidines and piperidines, highly desirable. Other nitrogen containing compounds including amines, enamines and imines, are valuable and commercially important bulk chemicals, speciality chemicals and pharmaceuticals.4 Amongst various synthetic routes, hydroamination, the direct formation of a new carbon-nitrogen bond by addition of an amine to an unsaturated carbon-carbon bond, is of particular significance.5 The reaction offers a potentially atom-efficient pathway starting from readily accessible alkenes and alkynes. 6'7'w ° The hydroamination of alkenes is more difficult compared to that of alkynes because of the lower reactivity and electron density of carbon-carbon double bonds.11 A particular challenge is the reversal of stereochemistry to obtain the anti-Markovnikov product.12 During recent years, hydroamination became a widely explored operation in the synthesis of nitrogen heterocycles and complex nitrogenous molecules in general. The Markovnikov addition of protected amines to alkynes is also now an established synthetic strategy. In early studies, hydroaminations were mostly triggered by alkali and lanthanide metals, followed by a shift in focus to the use of zirconium, titanium5,13 and late transition metal catalysts.14 Most of these are employed as homogenous catalysts, though new strategies for the immobilisation of these have gained and will undoubtedly continue to gain increased importance.103 Acid-catalysed hydroaminations have been developed from related, well studied methods of carbon-oxygen bond formation using acid catalysts.
Load more

Recommended publications
  • Microgram Journal, Vol 3, Number 2
    MICROGRAM Laboratory Operations Division Office Of Science And Drug Abuse Prevention BUREAU OF NARCOTICS & DANGEROUS DRUGS / U.S. DEPARTMENT OF JUSTICE / WASHINGTION, D.C. 20537 Vol.III, No. 2 March-April, 1970 STP (4-Methyl-2,5-dimethoxyamphetamine) hydrochloride was found coating the inside of capsules sent to BNDDfrom Germany. The capsules were clear, hard gelatin, standard shape size No. o. Average weight was 114 milligrams. Each capsule had a white crystalline coating on inner surface of capsule body. Apparently a measu~ed amount of solution had been placedin the cap·sule body, after which it was rotated to spread the solution on the inner surface. The substance contained 8. 7 milli­ grams STP (DOM)HCl per ca·psule. · These were the first STP capsules of this type seen by our laboratory. A few years ago, capsules were ob­ tained in the U.S. similarly coated with LSD. STP (Free Base) on laboratory filter paper, also from Germany, was seen for the first time in our laboratory. The STP spots, containing approxi­ mately 8 miliigrams STP base each, were 5/8 to 3/4 inch in diameter. The paper was 1\ inches square. Phencyclidine (Free Base) was recently analyzed on parsley leaves. Called "Angel DUst, 11 the phencyclidine on two samples of leaves was 2.6% and 3.6%. Approximately thirty pounds of 94% pure powder was also analyzed. (For identification of phencyclidine base, see Microgram, II, 1, p.3 (Jan 1969). IMITATIONSof well-known drug products are examined frequently in our Special Testing and Research Laboratory. Many of these are well made preparations and closely resemble the imitated product.
    [Show full text]
  • Plants and Parts of Plants Used in Food Supplements: an Approach to Their
    370 ANN IST SUPER SANITÀ 2010 | VOL. 46, NO. 4: 370-388 DOI: 10.4415/ANN_10_04_05 ES I Plants and parts of plants used OLOG D in food supplements: an approach ETHO to their safety assessment M (a) (b) (b) (b) D Brunella Carratù , Elena Federici , Francesca R. Gallo , Andrea Geraci , N (a) (b) (b) (a) A Marco Guidotti , Giuseppina Multari , Giovanna Palazzino and Elisabetta Sanzini (a)Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare; RCH (b) A Dipartimento del Farmaco, Istituto Superiore di Sanità, Rome, Italy ESE R Summary. In Italy most herbal products are sold as food supplements and are subject only to food law. A list of about 1200 plants authorised for use in food supplements has been compiled by the Italian Ministry of Health. In order to review and possibly improve the Ministry’s list an ad hoc working group of Istituto Superiore di Sanità was requested to provide a technical and scientific opinion on plant safety. The listed plants were evaluated on the basis of their use in food, therapeu- tic activity, human toxicity and in no-alimentary fields. Toxicity was also assessed and plant limita- tions to use in food supplements were defined. Key words: food supplements, botanicals, herbal products, safety assessment. Riassunto (Piante o parti di piante usate negli integratori alimentari: un approccio per la valutazione della loro sicurezza d’uso). In Italia i prodotti a base di piante utilizzati a scopo salutistico sono in- tegratori alimentari e pertanto devono essere commercializzati secondo le normative degli alimenti. Le piante che possono essere impiegate sono raccolte in una “lista di piante ammesse” stabilita dal Ministero della Salute.
    [Show full text]
  • Food and Health in Europe: Europe: in Health and Food WHO Regional Publications
    Food and health in Europe: Food and health WHO Regional Publications European Series, No. 96 a new basis for action Food and health in Europe: a new basis for action 96 The World Health Organization was established in 1948 as a specialized agency of the United Nations serving as the directing and coordinating authority for international health matters and public health. One of WHO’s constitutional functions is to provide objective and reliable information and advice in the field of human health, a responsibility that it fulfils in part through its publications programmes. Through its publications, the Organization seeks to support national health strategies and address the most pressing public health concerns. The WHO Regional Office for Europe is one of six regional offices throughout the world, each with its own programme geared to the particular health problems of the countries it serves. The European Region embraces some 870 million people living in an area stretching from Greenland in the north and the Mediterranean in the south to the Pacific shores of the Russian Federation. The European programme of WHO therefore concentrates both on the problems associated with industrial and post-industrial society and on those faced by the emerging democracies of central and eastern Europe and the former USSR. To ensure the widest possible availability of authoritative information and guidance on health matters, WHO secures broad international distribution of its publications and encourages their translation and adaptation. By helping to promote and protect health and prevent and control disease, WHO’s books contribute to achieving the Organization’s principal objective – the attainment by all people of the highest possible level of health.
    [Show full text]
  • Towards a Molecular Understanding of the Biosynthesis of Amaryllidaceae Alkaloids in Support of Their Expanding Medical Use
    Int. J. Mol. Sci. 2013, 14, 11713-11741; doi:10.3390/ijms140611713 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 www.mdpi.com/journal/ijms Review Towards a Molecular Understanding of the Biosynthesis of Amaryllidaceae Alkaloids in Support of Their Expanding Medical Use Adam M. Takos and Fred Rook * Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +45-3533-3343; Fax: +45-3533-3300. Received: 28 April 2013; in revised form: 26 May 2013 / Accepted: 27 May 2013 / Published: 31 May 2013 Abstract: The alkaloids characteristically produced by the subfamily Amaryllidoideae of the Amaryllidaceae, bulbous plant species that include well know genera such as Narcissus (daffodils) and Galanthus (snowdrops), are a source of new pharmaceutical compounds. Presently, only the Amaryllidaceae alkaloid galanthamine, an acetylcholinesterase inhibitor used to treat symptoms of Alzheimer’s disease, is produced commercially as a drug from cultivated plants. However, several Amaryllidaceae alkaloids have shown great promise as anti-cancer drugs, but their further clinical development is restricted by their limited commercial availability. Amaryllidaceae species have a long history of cultivation and breeding as ornamental bulbs, and phytochemical research has focussed on the diversity in alkaloid content and composition. In contrast to the available pharmacological and phytochemical data, ecological, physiological and molecular aspects of the Amaryllidaceae and their alkaloids are much less explored and the identity of the alkaloid biosynthetic genes is presently unknown. An improved molecular understanding of Amaryllidaceae alkaloid biosynthesis would greatly benefit the rational design of breeding programs to produce cultivars optimised for the production of pharmaceutical compounds and enable biotechnology based approaches.
    [Show full text]
  • Botanical Medicine
    prohealth QUICK REFERENCE EVIDENCE INFORMED BOTANICAL MEDICINE ,ĞƌďƐ͕ŶƵƚƌŝƟŽŶ͕ŚŽƌŵŽŶĞƐΘŵĞĚŝĐĂƟŽŶƐ ƌ͘DĂƌŝƐĂDĂƌĐŝĂŶŽΘƌ͘EŝŬŝƚĂ͘sŝnjŶŝĂŬ Introduction ............... 1 Botanical Studying Tips ................. iii Plant Harvesting ............................ vi Intro Intro Food is Medicine ........7 3URWHLQIDW¿EHUFDUERK\GUDWHV .... 9 A Vitamins & minerals .......................14 B Actions ....................... 31 C Constituents............... 59 D Pharmacy ................... 73 E Monographs A-Z.... ..... 85 F Appendix .................... 370 G Toxicology, CIs & Safe Dosing .............370 +HUEVLQ3UHJQDQF\ ............................. 376 H +HUEVLQ3HGLDWULFV .............................. 377 I 13/(; ERDUGH[DPKHUEOLVW ............ 378 +HUEVE\)DPLO\ ................................... 379 J +HUE'UXJ1XWULHQW,QWHUDFWLRQV .......... 382 K Medications (drug & use) .....................386 L Index .......................... 403 +HUEVE\ODWLQQDPH ............................. 406 M +HUEVE\FRPPRQQDPH ..................... 407 N Congratulations RQPDNLQJWKHEHVWLQYHVWPHQWRI\RXUOLIH\RXURZQHGXFDWLRQDQG\RXU O FRQWLQXHGVHUYLFHWR\RXUSDWLHQW¶VTXDOLW\RIOLIH7RKHOSVXSSRUW\RXWKLVWH[WZDVFUHDWHG P DVWKHPRVWXSWRGDWHIXQFWLRQDODQGFRVWHIIHFWLYHFOLQLFDOWH[WDYDLODEOH&RXQWOHVVKRXUVRI UHVHDUFK GHVLJQZHUHVSHQWWRGHYHORSWKHFRQWHQW IRUPDW,QIRUPDWLRQVRXUFHVLQFOXGH Q KXQGUHGVRIRULJLQDOSHHUUHYLHZHGUHVHDUFKDUWLFOHVZLWKFXWWLQJHGJHLQIRUPDWLRQ GHFDGHVRI R HYLGHQFHLQIRUPHGEHVWSUDFWLFHV PXOWLGLVFLSOLQDU\FOLQLFDOH[SHULHQFHZLWKDIRFXVRQresults S based medicine. ,QRUGHUWRJHWWKHPRVWFOLQLFDOXWLOLW\IURPWKLVWH[WLWPXVWEHDYDLODEOHDWDOOWLPHVDVVXFK
    [Show full text]
  • Alkaloids Volume 1
    A Specialist Periodical Report The Alkaloids Volume 1 A Review of the Literature Published between January 1969 and June 1970 Senior Reporter J . E. Saxton, Department of Organic Chemistry, The University of Leeds Reporters A. R. Battersby, Cambridge University K. W. Bentley, Reckitt and Sons Ltd., Hull 0. E. Edwards, National Research Council of Canada, Ottawa R. Goutarel, Centre Nationale de la Recherche Scientifique, Gif-sur- Yvette, France A. Gorman, Manchester University R. B. Herbert, University of Leeds M. Hesse, University of Zurich W. H. Hopff, University of Zurich J. A. Joule, Manchester University E. Schlittler, Heidelberg University H. Schmid, University of Zurich V. A. Snieckus, University of Waterloo, Canada E. W. Warnhoff, University of Western Ontario, Canada P. G. Waser, University of Zurich SBN: 85186 257 8 0 Copyright 1971 The Chemical Society Burlington House, London, WIV OBN Set in Times on Monophoto Filmsetter and printed offset by J. W. Arrowsmith Ltd., Bristol, England Made in Great Britain Foreword This volume is the first in the series of annual Specialist Periodical Reports devoted to the chemistry of the Alkaloids. In preparing this first volume our aim has been not simply to record progress during a selected period, but also to include whatever background material and earlier references are necessary to enable the new work to be placed in perspective in its own particular area; in consequence we hope that the reader, whether the alkaloid specialist or the general reader, will be able to read and benefit from the discussions presented here with the minimum of reference to the standard monographs on the subject.
    [Show full text]
  • Appendix: Drug Dosing in Renal Failure
    44. Drug dosage in renal failure Appendix: Drug dosing in renal failure Abbreviations used: ACE: angiotensin-converting enzyme AV: atrioventricular BUN: blood urea nitrogen CCr: Creatinine clearance CAPD: continuous ambulatory peritoneal dialysis CHF: congestive heart failure CMV: cytomegalovirus CNS: central nervous system CRRT: continuous renal replacement therapy CSA/FK: cyclosporine A and tacrolimus CVD: cardiovascular disease CVVH: Continuous venovenous hemofiltration DVT: deep vein thrombosis ESRD: end-stage renal disease GI: gastrointestinal GFR: glomerular filtration rate HBV: hepatitis B virus HD: hemodialysis HDL: high-density lipoprotein HIT: heparin-induced thrombocytopenia HSV: herpes simplex virus INR: international normalized ratio IV: intravenous MI: myocardial infarction MMF: mycophenolate mofetil NA: not applicable NC: No data: no change required NSAIDs: nonsteroidal anti-inflammatory drugs TB: tuberculosis TDM: therapeutic drug monitoring VD: volume of distribution VZV: varicella zoster virus. 919 920 Table 2 . Antibacterial agents % of drug Dosage adjustment for renal failure with GFR Method of dosage adjustment Drug Normal dosage excreted (ml/min): Comments renally >50 10−50 <10 HD CAPD CVVH Aminoglycosides Group toxicity: all agents in this group are nephrotoxic and ototoxic; ototoxicity is worse when the patient is hyperbilirubinemic; measure serum levels for efficacy and toxicity; peritoneal absorption increases with presence of inflammation. V increases with edema, obesity, and ascites D Streptomycin 7.5 mg/kg q. 12 hr 60% q. 24 hr q. 24−72 hr q. 72−96 hr May be less nephrotoxic than other Half normal 20−40 mg/L/ Dose for GFR (1.0 g q. 24 hr members of class dose after day 10−50 ml/min; for TB) dialysis measure levels Kanamycin 7.5 mg/kg q.
    [Show full text]
  • Supporting Information
    Supporting Information © Copyright Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, 2007 How Many Traditional Chinese Medicine Components Have Been Recognized by Modern Western Medicine? A Chemoinformatic Analysis and Implications for Finding Multicomponent Drugs De-Xin Kong, Xue-Juan Li, Guang-Yan Tang and Hong-Yu Zhang Table S1. Common agents in TCMD and CMC database. TCMD TCMD Name CMC number CMC Name number 8793 Serotonine MCMC00000036 SEROTONIN 3033 Dulcitol MCMC00000037 SORBITOL 7311 Noradrenaline MCMC00000052 NOREPINEPHRINE 3016 Dopamine MCMC00000060 DOPAMINE 9994 Tyramine MCMC00000062 TYRAMINE 4072 Glycine MCMC00000134 GLYCINE 4065 Glycerol MCMC00000141 GLYCERIN 813 L-Aspartic acid MCMC00000142 ASPARTIC ACID 380 Allyl isothiocyanate MCMC00000148 ALLYL ISOTHIOCYANATE 9078 Stearic acid MCMC00000151 STEARIC ACID 10032 Urea MCMC00000152 UREA 1237 Caffeine MCMC00000179 CAFFEINE 6687 2-Methyl-1,4-naphthoquinone MCMC00000187 MENADIONE 7615 Papaverine MCMC00000198 PAPAVERINE 7221 Nicotinic acid MCMC00000223 NIACIN 993 Benzyl ethyl alcohol MCMC00000229 PHENYLETHYL ALCOHOL 8204 Pyridoxine MCMC00000287 PYRIDOXINE 965 Benzoic acid MCMC00000292 BENZOIC ACID 7481 Orotic acid MCMC00000293 OROTIC ACID 2591 Dicoumarin MCMC00000296 DICUMAROL 10205 Vitamin A MCMC00000318 RETINOL 6026 D-Mannitol MCMC00000331 MANNITOL 8564 Salicylic acid MCMC00000332 SALICYLIC ACID 1693 Citric acid MCMC00000419 CITRIC ACID 10208 Vitamin B5 MCMC00000432 PANTOTHENIC ACID 5467 Khellin MCMC00000452 KHELLIN 9626 Theobromine MCMC00000463 THEOBROMINE 7843 Phytic acid MCMC00000465
    [Show full text]
  • Introduction (Pdf)
    Dictionary of Natural Products on CD-ROM This introduction screen gives access to (a) a general introduction to the scope and content of DNP on CD-ROM, followed by (b) an extensive review of the different types of natural product and the way in which they are organised and categorised in DNP. You may access the section of your choice by clicking on the appropriate line below, or you may scroll through the text forwards or backwards from any point. Introduction to the DNP database page 3 Data presentation and organisation 3 Derivatives and variants 3 Chemical names and synonyms 4 CAS Registry Numbers 6 Diagrams 7 Stereochemical conventions 7 Molecular formula and molecular weight 8 Source 9 Importance/use 9 Type of Compound 9 Physical Data 9 Hazard and toxicity information 10 Bibliographic References 11 Journal abbreviations 12 Entry under review 12 Description of Natural Product Structures 13 Aliphatic natural products 15 Semiochemicals 15 Lipids 22 Polyketides 29 Carbohydrates 35 Oxygen heterocycles 44 Simple aromatic natural products 45 Benzofuranoids 48 Benzopyranoids 49 1 Flavonoids page 51 Tannins 60 Lignans 64 Polycyclic aromatic natural products 68 Terpenoids 72 Monoterpenoids 73 Sesquiterpenoids 77 Diterpenoids 101 Sesterterpenoids 118 Triterpenoids 121 Tetraterpenoids 131 Miscellaneous terpenoids 133 Meroterpenoids 133 Steroids 135 The sterols 140 Aminoacids and peptides 148 Aminoacids 148 Peptides 150 β-Lactams 151 Glycopeptides 153 Alkaloids 154 Alkaloids derived from ornithine 154 Alkaloids derived from lysine 156 Alkaloids
    [Show full text]
  • NAST 1993 Annual Report
    NAST Annual Report 1993 ATIONAL ACADEMY OF SCIENCE AND TECHNOLOGY Republic of the Philippines ~993 NAST Annual Report 1993 NATIONAL ACADEMY OF SCIENCE AND TECHNOWGY TAPI Bldg.• DOST Compound Bicutan. Taguig. Metro Manila FOREWORD The National Academy of Science and Technology, the recognition and advisory body on science and technology, presents this annual report on the Academy's programs and activities for Calendar Year 1993. YRIT, M.D. President CONTENTS NAST Recognition Function New Academicians ................................................................................................ 1 1993 Outstanding Young Scientist (OYS) Awards ............................................. 1 1993 NAST-TWAS Science Prize (Physics) ....................................................... 8 1993 Awards for Outstanding Published Papers ................................................. 8 Benefits of Academicians .................................................................................... 13 Advisory Function ...................................................................................................... 16 15th Annual Scientific Meeting Guidelines on Ethics for Researchers ................................................................ 16 Advice ................................................................................................ - ................. 19 Botanical Garden ................................................................................................. 20 International Linkages .................................................................................
    [Show full text]
  • Organic Seminar Abstracts
    LIB RA R.Y OF THE UN 1VERSITY or 1 LLI NOIS Q.541 pt.l Return this book on or before the Latest Date stamped below. Theft, mutilation, and underlining of books are reasons for disciplinary action and may result in dismissal from the University. University of Illinois Library L161— O-1096 Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/organicsemi1962631univ ORGANIC SEMINAR ABSTRACTS I962-I963 IVERSITY OF ILLINOIS LIBRARY Paging varies but this is complete. Department of Chemistry and Chemical Engineering University of Illinois ORGANIC SEMIHAR ABSTRACTS 1962-1963 Semester I Department of Chemistry and Chemical Engineering University of Illinois SEMINAR TOPICS I Semester 1962-I963 Introduction of Functionality in the Angular Position of Fused Ring; Systems G. E. Wilson, Jr 1 Dinitrocyclohexanes Philip C. Kelley ......... 7 it -Complexes of Transition Metals with Mono-olefins M. P. Dixon 16 Structural Studies of Macrocyclic Pentaene Antibiotics G. Leadbeiter ...... Recent Applications of the Wittig Reaction H. E. Dunn . 33 Chemistry of Cyclic Azo Compounds T. II. Fisher ho The Mechanism of the Benzidine Rearrangement Richard A. Laursen . k-S) Conformational Studies of Five-membered Rings R. L. Buckson 58 Structure of Catalposide Walter J. Musliner 67 Recent Investigations on Morphine and Related Compounds Richard F, Schimbor 7^- The Biosynthesis of Branched Chain Fatty Acids W. P. O'Neill G3 The Photolysis of Diazoketones T. M. Warne 92 Nuclear Magnetic Double Resonance John P. Petrovich ........ 100 Stereochemistry, Synthesis and Biogenesis of Tropanes Richard K. Olsen 109 cis -trans Isomerization Mechanisms in Acid Solution L.
    [Show full text]
  • Yam)—An Appraisal of Nutritional and Therapeutic Potentials
    foods Review The Dioscorea Genus (Yam)—An Appraisal of Nutritional and Therapeutic Potentials Jude E. Obidiegwu 1,* , Jessica B. Lyons 2 and Cynthia A. Chilaka 3 1 National Root Crops Research Institute, Umudike, Km 8 Umuahia-Ikot Ekpene Road, P.M.B 7006 Umuahia, Abia State, Nigeria 2 Department of Molecular and Cell Biology and Innovative Genomics Institute, University of California, Berkeley, 142 Weill Hall #3200, Berkeley, CA 94720-3200, USA; [email protected] 3 Institute of Pharmacology and Toxicology, Julius Maximilian University of Würzburg, Versbacher Straβe 9, 97078 Würzburg, Germany; [email protected] or [email protected] * Correspondence: [email protected] Received: 8 August 2020; Accepted: 12 September 2020; Published: 16 September 2020 Abstract: The quest for a food secure and safe world has led to continuous effort toward improvements of global food and health systems. While the developed countries seem to have these systems stabilized, some parts of the world still face enormous challenges. Yam (Dioscorea species) is an orphan crop, widely distributed globally; and has contributed enormously to food security especially in sub-Saharan Africa because of its role in providing nutritional benefits and income. Additionally, yam has non-nutritional components called bioactive compounds, which offer numerous health benefits ranging from prevention to treatment of degenerative diseases. Pharmaceutical application of diosgenin and dioscorin, among other compounds isolated from yam, has shown more prospects recently. Despite the benefits embedded in yam, reports on the nutritional and therapeutic potentials of yam have been fragmented and the diversity within the genus has led to much confusion. An overview of the nutritional and health importance of yam will harness the crop to meet its potential towards combating hunger and malnutrition, while improving global health.
    [Show full text]