Stereoselective Total Synthesis of Marine Cyclodepsipeptide Calcaripeptides A–C

The first stereoselective total syntheses of marine cyclodepsipeptides, calcaripeptides A–C, have been accomplished. Emphasis was given particularly in identification of an efficient strategy for the macrocyclization. The notable features of our synthesis include Evans alkylation, Crimmins syn-aldol, Crimmins acetate aldol, Wittig olefination, and Shiina macrolactonization reactions. An anomaly in the 1H NMR of the proposed calcaripeptide B has been amended during this synthetic study.

海洋环酯肽（cyclodepsipeptides）类化合物钙肽A-C（calcaripeptides A–C）的首例立体选择性全合成已顺利完成。本研究重点聚焦于高效大环化（macrocyclization）策略的确立。本次合成的关键特色包括Evans烷基化反应、Crimmins顺式羟醛缩合反应、Crimmins乙酸酯羟醛缩合反应、Wittig烯化反应以及Shiina大环内酯化反应。在本合成研究过程中，我们修正了此前文献所报道的钙肽B的1H核磁共振（1H NMR）谱图异常问题。