Enantiospecific total synthesis of (-)-bakkenolide III and formal total synthesis of (-)-bakkenolides B, C, H, L, V, and X.

A concise enantiospecific synthesis of (-)-bakkenolide III was accomplished from (S)-(+)-carvone. The key step involved radical cyclization of an iodoketone intermediate which afforded the cis-hydrindanone skeleton. Further synthetic transformations generated bakkenolide III, which also constitutes the formal total synthesis of (-)-bakkenolides, B, C, H, L, V, and X.