Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland.
Angew Chem Int Ed Engl. 2021 May 25;60(22):12392-12395. doi: 10.1002/anie.202103580. Epub 2021 Apr 23.
We report herein the enantioselective total synthesis of three monoterpene indole alkaloids, namely, (+)-alstilobanine C, (+)-undulifoline, and (-)-alpneumine H. The key features of our synthesis include: a) introduction of chirality via enantioselective deprotonation of a prochiral 4-substituted cyclohexanone; b) use of methoxymethyl (MOM) ether as both a hydroxyl protective group and a latent oxonium species for the formation of bridged oxepane and c) domino double reductive cyclization to build both the indole and the piperidine ring at the end of the synthesis. The synthesis confirmed the absolute configuration of these natural products assigned based on the biogenetic hypothesis.
我们在此报告三种单萜吲哚生物碱，即（+）-阿尔替洛巴宁 C、（+）-波纹碱和（-）-阿尔诺明 H 的对映选择性全合成。我们合成的关键特点包括：a）通过手性前手性 4-取代环己酮的对映选择性去质子化引入手性；b）使用甲氧基甲基（MOM）醚作为羟基保护基和潜在的氧鎓物种，用于形成桥环环氧乙烷；c）串联双还原环化，在合成的最后构建吲哚和哌啶环。该合成证实了基于生物发生假设分配的这些天然产物的绝对构型。
