A Short Access to the Skeleton of Elisabethin A and Formal Syntheses of Elisapterosin B and Colombiasin A
作者:Johannes Preindl、Christian Leitner、Simon Baldauf、Johann Mulzer
DOI:10.1021/ol501998y
日期:2014.8.15
described, which opens a formal access to the diterpenes Elisapterosin B and Colombiasin A as well. Key reactions were an intermolecular endo-selective Diels–Alder reaction to generate the decalin part of the molecule, a chemo- and diastereoselective allylation of an aldehyde with allylzinc, a palladium ene annulation of the cyclopentane ring, and a novel sulfonium ylide induced fragmentation of a polycyclic
描述了Elisabethin A骨架4的简短立体选择性合成,这为二萜Elisapterosin B和Colombiasin A的正式开通提供了条件。关键反应是分子间内选择性Diels-Alder反应以生成分子的十氢萘部分,醛与烯丙基锌的化学和非对映选择性烯丙基化,环戊烷环的钯烯环化,以及新型sulf内鎓盐诱导的片段化多环酮。对于C-2的关键差向异构,已经获得了更多的见解。