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Heterocycles in Life and Society Heterocycles in Life and Society Heterocycles in Life and Society An Introduction to Heterocyclic Chemistry, Biochemistry and Applications Second Edition by ALEXANDER F. POZHARSKII Soros Professor of Chemistry, Southern Federal University, Russia ANATOLY T. SOLDATENKOV Professor of Chemistry, Russian People’s Friendship University, Russia ALAN R. KATRITZKY Kenan Professor of Chemistry, University of Florida, Gainesville, USA A John Wiley & Sons, Ltd., Publication This edition first published 2011 c 2011 John Wiley & Sons, Ltd Registered office John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, United Kingdom For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com. The right of the author to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. The publisher and the author make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of fitness for a particular purpose. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for every situation. In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of experimental reagents, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each chemical, piece of equipment, reagent, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. The fact that an organization or Website is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers should be aware that Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read. No warranty may be created or extended by any promotional statements for this work. Neither the publisher nor the author shall be liable for any damages arising herefrom. Library of Congress Cataloging-in-Publication Data Pozharskii, A. F. (Aleksandr Fedorovich) Heterocycles in life and society / Alexander F. Pozharskii, Alan R. Katritzky, Anatoly Soldatenkov. – 2nd ed. p. cm. ISBN 978-0-470-71411-9 (hardback) – ISBN 978-0-470-71410-2 (paper) 1. Heterocyclic chemistry. I. Katritzky, Alan R. II. Soldatenkov, A. T. (Anatoly Timofeevich) III. Title. QD400.P6713 2011 547.59–dc22 2010054024 A catalogue record for this book is available from the British Library. Print ISBN: 978-0-470-71411-9 (H/B) 978-0-470-71410-2 (P/B) ePDF ISBN: 978-1-119-99838-9 oBook ISBN: 978-1-119-99837-2 ePub ISBN: 978-1-119-97013-2 eMobi ISBN: 978-1-119-97014-9 Typeset in 9/11pt Times Roman by Laserwords Private Limited, Chennai, India Printed in Great Britain by Antony Rowe Ltd, Chippenham, Wiltshire Contents Preface to Second English Edition ix Preface to First English Edition xiii 1. Molecular Rings Studded With Jewels 1 1.1 From Homocycle to Heterocycle 1 1.2 Building Heterocycles From Benzene 2 1.3 Some More Kinds of Heterocycles 6 1.4 Problems 8 1.5 Suggested Reading 8 2. Why Nature Prefers Heterocycles 11 2.1 Reactions for all Tastes 11 2.2 Heterocycles as Acids and Bases 14 2.3 Heterocycles and Metals 15 2.4 ‘There are Subtle Ties of Power...’17 2.4.1 The van der Waals-London Interactions 18 2.4.2 Hydrogen Bonding 19 2.4.3 Electrostatic Interactions 21 2.4.4 Molecular Complexes 21 2.4.5 Hydrophobic Forces 25 2.5 Tautomerism: Heterocycles and Their ‘Masks’ 27 2.6 Problems 31 2.7 Suggested Reading 33 3. Heterocycles and Hereditary Information 35 3.1 Nucleic Acids 35 3.2 The Double Helix 38 3.3 How One DNA Doubles Itself 42 3.4 Protein Synthesis, Genetic Code and the Genome 45 3.5 What are Mutations? 50 3.6 Mysterious Telomeres 54 3.7 Gene Expression 55 3.8 Problems 60 3.9 Suggested Reading 61 4. Enzymes, Coenzymes and Vitamins 63 4.1 Molecular Robots 63 4.2 Coenzymes and Enzymes as ‘Joint Molecular Ventures’ 66 vi Contents 4.2.1 Oxidative–Reductive Coenzymes 67 4.2.2 Coenzymes as Carriers of Molecular Species 78 4.3 Vitamins, the ‘Molecules of Health’ 97 4.4 Ribozymes: Vestiges of an Ancient World 99 4.5 Problems 103 4.6 Suggested Reading 104 5. Heterocycles and Bioenergetics 107 5.1 ATP as the Universal Currency of Energy 108 5.2 Breathing 111 5.2.1 Glycolysis 112 5.2.2 The Krebs Cycle, or the ‘Molecular Merry-Go-Round’ 115 5.2.3 The Respiratory Chain 118 5.3 Problems 122 5.4 Suggested Reading 123 6. Heterocycles and Photosynthesis 125 6.1 Chlorophyll: Sunlight-Receiving Antenna and Energy Carrier 126 6.2 What Daylight can Achieve 130 6.3 Photosynthesis Without Light 135 6.4 Problems 138 6.5 Suggested Reading 138 7. Heterocycles and Health 139 7.1 Medicines From a Natural Storehouse 139 7.2 Heterocycles Versus Infectious Microbes 143 7.2.1 In Search of ‘Magic Bullets’ 143 7.2.2 Sulfanilamides and Heterocycles 144 7.2.3 Antibiotics 146 7.2.4 Antibiotics From the Ocean’s Depths 152 7.2.5 Heterocyclic Antifungal Agents 155 7.2.6 Heterocycles Against Parasitic Diseases 155 7.3 Heterocycles and Viral Infections 158 7.4 Heterocycles and the Diseases of Our Century 162 7.4.1 Heterocycles to Cure Stress, Brain Disorders and Pain 163 7.4.2 Heterocycles and Cardiovascular Diseases 169 7.4.3 Heterocycles and Malignant Tumors 173 7.5 Heterocyclic Molecules in Combat with Ulcers and Sexual Dysfunctions 178 7.6 Problems 181 7.7 Suggested Reading 182 8. Heterocycles in Agriculture 185 8.1 A Century of Chemical Warfare Against Weeds 186 8.2 Regulators of Plant Growth 190 8.3 The Struggle Against Voracious Insects 193 8.4 Resisting the Kingdoms of Mustiness and Rot 200 8.5 Heterocycles in Animal Husbandry 202 8.6 Combinatorial Chemistry and Functional Genomics in the Synthesis of Biologically Active Heterocyclic Compounds 202 Contents vii 8.7 Problems 205 8.8 Suggested Reading 207 9. Heterocycles in Industry and Technology 209 9.1 Heterocycles and Natural Colors 209 9.2 Dyes 211 9.2.1 From Imperial Cloaks to Jeans 211 9.2.2 ‘Cyanine’ Means Azure 214 9.2.3 Phthalocyanines: Sometimes Better than Porphyrins 215 9.2.4 The Anchoring of Dyes 217 9.3 Fluorescent Agents 218 9.3.1 Why They Shine 218 9.3.2 Safety and Aesthetics 219 9.3.3 How to Convert White into Snow White 220 9.3.4 Markers and Tracers 221 9.3.5 Imaging and Diagnostic Agents 222 9.3.6 Lasers Containing Heterocyclic Luminophores 226 9.4 Color Change Compounds 231 9.5 Fire Retardancy 233 9.6 Photographic Materials and Recorders of Information 235 9.7 Heterocycles as Food Additives 237 9.8 Heterocycles as Cosmetics and Perfumery Ingredients 241 9.9 Other Applications 243 9.10 Problems 245 9.11 Suggested Reading 246 10. Heterocycles and Supramolecular Chemistry 247 10.1 Molecular Recognition and Host–Guest Interactions 248 10.1.1 Cation Receptors 248 10.1.2 Anion-, Betaine- and Ionic Associated Receptors 257 10.1.3 Receptors for Neutral Molecules 259 10.1.4 Molecular Carcerands 261 10.1.5 Molecular Containers for the Proton 262 10.2 Self-Assembling Molecular Systems 267 10.3 Problems 272 10.4 Suggested Reading 274 11. Heterocycles and Twenty-First Century Challenges 275 11.1 Energy Problem 275 11.1.1 Biofuels 275 11.1.2 Hydrogen as a Fuel 276 11.1.3 Direct Use of Solar Energy 278 11.1.4 Conducting Materials 286 11.2 Ecology and Green Chemistry 293 11.3 Biotechnology and Related Problems 299 11.3.1 Enzyme Technologies 299 11.3.2 DNA Technologies 304 11.3.3 New Trends in Health Care 309 11.3.4 Heterocycles as Molecular Sensors 310 viii Contents 11.4 From Molecular Devices to Molecular Computer 315 11.5 Problems 321 11.6 Suggested Reading 322 12.
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