Enantioselective Total Synthesis of Marine Diterpenoid Clavulactone

摘要

Clavulactone (1) and clavirolides A-F (Scheme 1) are cytotoxic tricyclic diterpenoids of the dolabellane family, isolated from samples of the Pacific soft coral Clavularia viridis, which was collected off the Xisha Islands in the South China Sea. The unique molecular architecture of these compounds is characterized by a tans-bicyclo[9.3.0]-tetradecane core bearing a bridging α,β-unsaturated lactone, four stereogenic centers, including a quaternary carbon center, and a multisubstituted cycloundecanone moiety that has a position-variable C=C bond (except clavirohde C).