Asymmetric Total Synthesis of (+)‐Mannolide C

Abstract

+)-Mannolide C is a complex hexacyclic C 20 cephalotane-type diterpenoid featuring a highly strained 7/6/ 6/5 tetracyclic core containing eight consecutive stereocenters and two bridging lactones. The first asymmetric total synthesis of (+)-mannolide C has been accomplished by lipase-mediated resolution, Ru-complex-catalyzed double ring-closing metathesis (RCM) reactions, Ni II -catalyzed diastereoselective Michael addition, and Mn III -catalyzed allylic oxidation as the key transformations.