Enantioselective Total Synthesis of (-)-Cephalotanin B

Angew Chem Int Ed Engl. 2023 Nov 20;62(47):e202312599. doi: 10.1002/anie.202312599. Epub 2023 Oct 19.

Abstract

Cephalotaxus diterpenoids are attractive natural products with intriguing molecular frameworks and promising biological features. As a structurally unusual member, (-)-cephalotanin B possesses an extraordinarily congested heptacyclic skeleton, three lactone units, and nine consecutive stereocenters. Herein, we report an enantioselective total synthesis of (-)-cephalotanin B based on a divergent asymmetric Michael addition reaction, a novel Pauson-Khand/deacyloxylation process discovered in the development of a second-generation stereoselective Pauson-Khand reaction protocol, and an epoxide-opening/elimination/dual-lactonization cascade to construct the challenging propeller-shaped A-B-C ring system as key transformations.

Keywords: We are grateful for financial support from the National Natural Science Foundation of China (21772153, 22071192) and the Science and Technology Department of Shaanxi Province (2019JM-151)..