Unified Strategy to Monoterpene Indole Alkaloids: Total Syntheses of (±)-Goniomitine, (±)-1,2-Dehydroaspidospermidine, (±)-Aspidospermidine, (±)-Vincadifformine, and (±)-Kopsihainanine A
作者:Olivier Wagnières、Zhengren Xu、Qian Wang、Jieping Zhu
DOI:10.1021/ja509329x
日期:2014.10.22
Total syntheses of (±)-goniomitine, (±)-1,2-dehydroaspidospermidine, (±)-aspidospermidine, (±)-vincadifformine, and (±)-kopsihainanine A were achieved featuring two common key steps: (1) a palladium-catalyzed decarboxylative vinylation that provides quick access to cyclopentene intermediates containing all of the carbons present in the natural products and (2) an integrated oxidation/reduction/cyclization
(±)-goniomitine、(±)-1,2-dehydroaspidospermidine、(±)-aspidospermidine、(±)-vincadifformine 和 (±)-kopsihainanine A 的全合成是通过两个常见的关键步骤实现的:(1) a钯催化的脱羧乙烯基化,可快速获得包含天然产物中存在的所有碳的环戊烯中间体和 (2) 用于骨架重组的综合氧化/还原/环化 (iORC) 序列,将环戊烯转化为五环结构天然产品。通过对 iORC 底物加入几何约束,可以控制环化过程的化学选择性(C7 与 N1 环化)和立体选择性(反式与顺式稠环系统)。