/soquinoline Alkaloids Research 1972-1977 /soquinoline Alkaloids Research 1972-1977 Maurice Shamma and Jerome L. Moniot The Pennsylvania State University University Park, Pennsylvania Plenwn Press· New York and London Library of Congress Cataloging in Publication Data Shamma, Maurice, 1926- Isoquinoline alkaloids research, 1972-1977. Includes bibliographical references and index. 1. Alkaloids. 2. Isoquinoline. I. Moniot, Jerome L., joint author. II. Title. QD421.S543 547.72 77-26929 ISBN-13: 978-1-4615-8821-4 e-ISBN-13: 978-1-4615-8819-1 DOl: 10.1007/978-1-4615-8819-1 ©1978 Plenum Press, New York Softcover reprint of the hardcover 1s t edition 1978 A Division of Plenum Publishing Corporation 227 West 17th Street, New York, N.Y. 10011 All rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permission from the Publisher The authors who set out to say something that no one has said before are to be regarded with mistrust. Max J. Friedlander PREFACE Substantial advances in the realm of isoquinoline alkaloids have occurred since The Isoquinoline Alkaloids, Chemistry and Pharmacology, was published in 1972. The present volume represents an effort to describe important developments since that time. The organization of the present book is essentially the same as in The Isoquinoline Alkaloids. Each chapter begins with a discussion of structural elucidation and synthesis, a description of typical reactions then follows, and the chapter ends with coverage of biogenesis, pharmacology, and spectroscopy. New chapters have had to be added to describe the completely new alkaloidal types discovered since 1972. These include baluchistanamine (an isoquinolone benzylisoquinoline dimer), the aporphine-pavine dimers, the 4,5-dioxoapor phines, the secoberbines, the 3-arylisoquinolines, eupolauridine, and very recently imerubrine. Another new chapter discusses the chemistry of the aristolo chic acids and aristolactams, a group of substituted phenanthrenes, obviously of isoquinoline derivation in spite of the fact that they do not incorporate a basic nitrogen function. The aristolochic acids and aristolactams were not in cluded in The Isoquinoline Alkaloids even though they were known at the time that book was written. On the other hand, one group of alkaloids which was included in The Isoquinoline Alkaloids and nevertheless was deemed not to belong properly in the present work is the naphthalenoisoquinolines, which include ancistro cladine and its relatives. These bases do not originate biogenetically· from tyrosine, and beside incorporating tetrahydroisoquinoline moieties show no clear structural relationship to the more orthodox isoquinoline alkaloids. As with The Isoquinoline Alkaloids, not all known or new isoquinoline alkaloids have been presented. Rather, selected examples have been discussed to illustrate specific principles or methods. For a complete listing of the iso quinoline alkaloids, the reader is referred to T. Kametani's The Chemistry of the Isoquinoline Alkaloids, Vol. 2, * and also to the annual reviews on isoquinoline alkaloids and the aporphinoids included in Specialist Periodical Reports, The t A lkalo ids. * The Sendai Institute of Heterocyclic Chemistry, Sendai, Japan (1974). t The Chemical Society, London. vii viii PREFACE Percentage reaction yields are given in parentheses under the proper struc tures. Infrared absorptions are quoted both in terms of wavelength and fre quency. Ultraviolet log values are given in brackets following the values. € Amax The literature up to about mid-1977 has been covered. All nuclear magnetic resonance data are given in I) values, and were obtained in deuteriochloroform solution unless stated otherwise. A special effort was made to include C-13 nuclear magnetic resonance values where available. The term "tetrahydroiso quinoline" refers to the 1, 2,3,4-tetrahydro system, and the prefix" nor" relates solely to the N-nor series. The authors would like to thank Drs. A. Patra and A. S. Rothenberg, as well as Mr. P. Chinnasamy, for commenting on the completed manuscript. A special debt is due senior editor, Mr. Ellis Rosenberg, and assistant managing editor, Ms. Betty Bruhns, for a dedicated effort in facilitating our work. Maurice Shamma Jerome L. Moniot CONTENTS Chapter 1. The Simple Isoquinolines 1.1. Introduction 1 1.2. Synthesis 2 1.2.1. Pictet-Spengier Cyclization 2 1.2.2. Bischler-Napieralski Cyclization 4 1.2.3. Pomeranz-Fritsch Cyclization 6 1.2.4. Photocyclization of N-Chloroacetylbenzylamines 7 1.2.5. Amination of Benzopyrylium Salts 7 1.2.6. A New Isoquinoline Synthesis via Ortho-Substituted Benzylamines 8 1.2.7. Cyclization of Aralkenyl-Substituted Quaternary Ammonium Salts . 8 1.3. Some Reactions of Simple Isoquinolines . 8 1.3.1. Oxidation . 8 1.3.2. Alkylation and Acylation 10 1.3.3. Fluorophore-Forming Reactions 14 1.3.4. Electrolytic Oxidation . 15 1.3.5. Rearrangements of 1,2-Dihydroisoquinolines 17 1.4. Biogenesis . 18 1.5. Pharmacology 20 1.6. CMR Spectroscopy 22 References and Notes 23 Chapter 2. The Benzylisoquinolines 27 2.1. Introduction 27 2.2. Synthesis 28 2.2.1. The Use of Reissert Compounds 28 2.2.2. Friedel-Crafts Alkylation and Acylation 29 2.2.3. Pictet-Spengler Condensation 31 2.2.4. The Pomeranz-Fritsch/Reissert Approach 32 2.2.5. Cyclization of N-Sulfonylphenethylamines 33 2.3. Reactions of Benzylisoquinolines . 34 2.3.1. Oxidation . 34 2.3.2. Reduction and the Chemistry of the Reduction Products. 34 2.3.3. Photolysis . 36 2.3.4. Acetonylation at C-6' . 38 2.3.5. Fission of Ring B 38 2.3.6. Rearrangement of 1,2-Dihydroisoquinolines 40 2.3.7. Transformation of a-Ketobenzylisoquinolines. 41 ix x CONTENTS 2.3.8. Electrolytic Oxidation . 42 2.3.9. Oxidative Dimerization 43 2.4. Conversion of Benzylisoquinolines to Morphine 44 2.5. Cryptopleurospermine, an Unusual Natural a-Dione 46 2.6. Biogenesis . 47 2.7. Pharmacology 49 2.8. NMR Spectroscopy 51 2.9. UV Spectroscopy. 52 References and Notes 52 Chapter 3. The Isoquinolones 57 3.1. Introduction 57 3.2. Siamine 57 3.3. Synthesis and Reactions of Isoquinolones 58 References . 60 Chapter 4. The Pavines and Isopavines . 61 4.1. Synthesis 61 4.1.1. Pavines 61 4.1.2. Isopavines 64 4.2. Biogenesis . 68 4.3. Pharmacology 68 4.4. Spectroscopy and Crystallography . 68 References and Notes . 69 Chapter 5. The Bisbenzylisoquinolines 71 5.1. Introduction 71 5.2. Stepinonine, an Unusual Bisbenzylisoquinoline 81 5.3. Synthesis 84 5.3.1. The Cava Modification of the Ullmann Reaction 84 5.3.2. The Inubushi Synthesis of Obaberine and Trilobine 85 5.3.3. The Use of Reissert Compounds . 88 5.4. Controlled Oxidation 89 5.5. Some General Methods for Functional Group Modification of Isoquinoline Alkaloids. 91 5.5.1. Selective Removal of an Aromatic Methyleliedioxy Group 91 5.5.2. Deoxygenation of a Phenol . 91 5.5.3. N-Demethylation of Tertiary Amines 91 5.5.4. N-Demethylation and N-Debenzylation of Quaternary Ammonium Salts 92 5.5.5. O-Demethylation and O-Debenzylation of Aromatic Ethers 92 5.5.6. Methylenation of Catechols . 93 5.5.7. O-Methylation and Protection of Phenols 93 5.5.8. Aromatic Hydroxylation or Methoxylation 93 5.6. Biogenesis . 93 5.7. Pharmacology 97 CONTENTS xi 5.8. Spectral Measurements and CD Curves 97 5.9. X-Ray Diffraction 99 References and Notes . 100 Chapter 6. Baluchistanamine: An Isoquinolone-Benzylisoquinoline Dimer. 103 6.1. Structure Elucidation and Synthesis 103 6.2. PMR Spectroscopy 105 6.3. UY Spectroscopy and Circular Dichroism 105 References . 105 Chapter 7. The Cularines lO7 7.1. Synthesis 107 7.2. Absolute Configuration. 109 7.3. An Approach to the Synthesis of Cancentrine . 110 7.4. CMR Spectroscopy 111 References . 111 Chapter 8. The Dibenzopyrrocolines 113 8.1. Synthesis 113 8.1.1. Benzyne Intermediates. 113 8.1.2. Enzymic Processes 115 References . 116 Chapter 9. The Proaporphines 117 9.1. Introduction 117 9.2. Revision of Stereochemistry of the Reduced Proaporphines 117 9.3. Synthesis 118 9.4. Pharmacology 119 9.5. Spectral Studies 119 References and Notes 120 Chapter 10. The Aporphines . 123 10.1. Introduction 123 10.2. Synthesis . 123 10.2.1. Photolysis 123 10.2.2. The Use of YOCI 126 3 10.2.3. The Use of YOF -TFA 126 3 10.2.4. Electrolytic Oxidation 135 10.2.5. Oxidation with Cuprous Chloride and Oxygen 136 10.2.6. The Use of Lead Tetraacetate; Hydroxylation at C-4 . 137 10.2.7. Benzyne Intermediates 138 10.2.8. Enzymic Oxidative Coupling . 139 10.2.9. Reissert Intermediates 139 10.2.10. Improved Pschorr CycIizations 140 10.2.11. Coupling with Thallium Tristrifluoroacetate 140 xii CONTENTS 10.3. Reactions of Aporphines 141 10.3.1. Oxidation and Formation of Dehydroaporphines and Oxoaporphines 141 10.3.2. Selective Cleavage of the Methylenedioxy Substituent. 142 10.3.3. Dimerization. 144 10.304. Hofmann and Emde Degradations 144 10.3.5. O-Acetylation i44 10.3.6. Hydroxylation 145 10.3.7. Selective O-Demethylation and N-Demethylation 145 10.3.8. Protonation and Formylation of Dehydroaporphines . 146 lOA. Absolute Configuration 146 10.5. Biogenesis. 147 10.6. Pharmacology 150 10.7. NMR Spectroscopy 152 References and Notes. 154 Chapter II. Pakistanamine: A Proaporphine-Benzylisoquinoline Dimer. 157 11.1. Synthesis . 157 References and Notes . 158 Chapter 12. The Aporphine-Benzylisoquinoline Dimers . 159 12.1. Introduction 160 12.2. Structural Elucidation. 160 12.3. Synthesis . 161 12.4. Reactions . 162 12.5. Biogenesis. 163 12.6. Pharmacology 164 12.7. PMR Spectroscopy 165 References and Notes . 165 Chapter 13. The Aporphine-Pavine Dimers 167 13.1. Introduction 167 13.2. Structural Elucidation. 167- 13.3. UV and IR Spectroscopy 170 References. 171 Chapter 14. The Oxoaporphines 173 14.1. Introduction 173 14.2. Synthesis . 173 14.3. Pharmacology 175 14.4. Spectral Characteristics 175 References and Notes. 176 Chapter 15. The Phenanthrenes 179 15.1. Structural Elucidation and Synthesis 179 15.2. Pharmacology 180