Institute of Organic Chemistry, University of Konstanz, Universitätsstrasse 10, Konstanz 78464, Germany.
Org Lett. 2022 Jul 8;24(26):4717-4721. doi: 10.1021/acs.orglett.2c00961. Epub 2022 May 11.
Herein, we report an enantioselective and convergent total synthesis of (+)-pepluanol A, a structurally intriguing diterpenoid natural product featuring a 5/6/7/3-fused tetracyclic skeleton, from known building blocks in 11 steps. The successful strategy relies on a phenyl selenide-mediated Morita-Baylis-Hillman type reaction as a connective step, forging the precursor for the key intramolecular Diels-Alder reaction to construct the congested 5/6/7-tricyclic framework. A diastereoconvergent cascade starting with an acid-induced removal of the C1-MOM protecting group followed by a retro-aldol/aldol reaction resulted in the formation of a single diastereomer. This stereoconvergency allowed for the successful substrate-controlled diastereoselective cyclopropanation of an advanced intermediate to establish the full carboskeleton of (+)-pepluanol A ().
在此，我们报告了 (+)-pepluanol A 的对映选择性和收敛性全合成，这是一种结构有趣的二萜天然产物，具有 5/6/7/3 稠合四环骨架，由已知砌块通过 11 步反应得到。成功的策略依赖于苯硒醚介导的 Morita-Baylis-Hillman 型反应作为连接步骤，形成关键的分子内 Diels-Alder 反应的前体，构建拥挤的 5/6/7-三环骨架。从酸诱导的 C1-MOM 保护基去除开始的非对映收敛级联反应，然后进行 retro-aldol/aldol 反应，导致单一非对映异构体的形成。这种立体转化允许成功地对高级中间体进行底物控制的环丙烷化，以建立 (+)-pepluanol A 的完整碳骨架（）。
