A Review Of The Literature Published Between September 1976 And August 1977

A Specialist Periodical Report Terpenoids and Steroids Volume 8 A Review of the Literature Published between September 1976 and August 1977 Senior Reporter J. R. Hanson, School of Molecular Sciences, University of Sussex Reporters G. Britton, University of Liverpool J. D. Connolly, University of Glasgow D.N. Kirk, Westfield College, London B. A. Marples, University of Technology, Loughborough T. Money, University of British Columbia, Vancouver, Canada R. B. b a t s , Bishop's University, Lennoxville, Quebec, Canada The Chemical Society Burlington House, London, WIV OBN ISBN 0-85186-326-4 ISSN 0300-5922 Library of Congress Catalog Card No. 74-615720 Copyright @ 1978 The Chemical Society All Rights Reserved No part of this book may be reproduced or transmitted in any form or by any means-graphic, electronic, including photocopying, recording, taping or information storage and retrieval systems-without written permission from The Chemical Society Set in Times on Linotron and printed offset by J. W. Arrowsmith Ltd., Bristol, England Made in Great Britain In trod uction During the year under review the number of known terpenoids has increased significantly, particularly amongst the sesqui- and di-terpenoids where a number of novel skeleta have been described. In a number of instances the novel diterpenoid skeleta are reminiscent of sesquiterpenoids. Marine organisms have provided the source of many new halogenated terpenoids. It is interesting to speculate o n the role of the halogen, particularly bromine, in the biosynthesis of these compounds. The sites of halogenation are in a number of instances those which would be expected if the halogen were playing a role in the cyclization of acyclic prenyl precursors. The format of these Reports has remained relatively constant from year t o year t o facilitate the location of subject matter. However, this year two changes have occurred. Firstly, as an experiment, the information on biosynthesis is contained within the chapters dealing with the individual group of terpenoids rather than as a separate chapter. Secondly, the steroid section has been recast t o minimize overlap. A report of the application of physical methods t o steroids forms o n e chapter whilst steroid reactions and partial syntheses are reported in the second. Total synthesis will be reviewed biennially. J. R. HANSON Contents Part I Terpenoids 3 Chapter 1 Monoterpenoids By R. 8.Yeats 1 Physical Measurements: Spectra etc.; Chirality 4 2 General Synthetic Reactions 9 3 Biogenesis, Occurrence, and Biological Activity 13 4 Acyclic Monoterpenoids 20 Terpenoid Synthesis from Isoprene 20 2,6-Dimethyloctanes 22 Halogenated Monoterpenoids 30 Artemisyl, Santolinyl, Lavandulyl, and Chrysanthemyl Derivatives 32 5 Monocyclic Monoterpenoids Cyclobutane Cyclopentanes, Iridoids p-Menthanes o-Menthanes m-Menthanes Tetramethy lcyclohexanes Dimethyleth ylcyclohexanes Cycloheptanes 35 35 35 39 46 46 6 Bicyclic Monoterpenoids Bicyclo[3,l,0]hexanes Bicyclo[2,2,l]heptanes Bicyclo[3,l ,l]heptanes Bicyclo[4,1,O]heptanes 48 7 Furanoid and Pyranoid Monoterpenoids 58 8 Cannabinoids and other Phenolic Monoterpenoids 61 46 47 48 48 49 53 56 V Contents vi Chapter 2 Sesquiterpenoids By T. Money 64 1 Farnesane 64 2 Mono- and Bi-cyclofarnesane 66 3 Bisabolane 67 4 Sesquipinane, Sesquicamphane, Sesquifenchane 71 5 Cuparane, Trichothecane, Laurane 73 6 Acorane, Cedrane, Carotane 76 7 Chamigrane, Widdrane, Thujopsane 79 8 Cadinane, Amorphane, Copacamp