A General Approach to the Asymmetric Synthesis of Lignans: (-)-Methyl Piperitol, (-)-Sesamin, (-)-Aschantin, (+)-Yatein, (+)-Dihydroclusin, (+)-Burseran, and (-)-Isostegane
作者:Dieter Enders、Vivien Lausberg、Giuseppe Del Signore、Otto Mathias Berner
DOI:10.1055/s-2002-20967
日期:——
enantioselective route was developed to access a great variety of lignans. The asymmetric synthesis of the 2,3-disubstituted γ-butyrolactones 9a-c could be improved in the case of aldol reactions by employing 2.2 equivalents of LiCl as an additive to provide, after purification, highly diastereo- and enantioenriched starting materials for the synthesis of the furofuran lignans (-)-methyl piperitol, (-)-sesamin
开发了一种高效、非对映和对映选择性的途径来获得多种木脂素。2,3-二取代的 γ-丁内酯 9a-c 的不对称合成可以在醛醇反应的情况下通过使用 2.2 当量的 LiCl 作为添加剂来改进,以在纯化后提供高度非对映和对映富集的起始原料用于合成呋喃木脂素 (-)-甲基胡椒醇、(-)-芝麻素和 (-)-aschantin。此外,γ-丁内酯15被转化为二苄基丁内酯木脂素(+)-亚丁醇、二苄基丁二醇型(+)-二氢簇素、四氢呋喃型(+)-burseran和二苯并环辛二烯型(-)-异甜菊素。