摘要:
Various 14-membered macrocyclic trienes underwent transannular Diels-Alder reactions to yield tetracyclic structures that are streoisomers of steroids. Due to the complexity of the effects at work during these reactions, a thorough molecular modeling study was carried out. Thus, some molecular mechanics, semiempirical and db initio methods were compared and the results were finally used to rationalize the experimental results. (C) 1998 Elsevier Science Ltd. All rights reserved.