Asymmetric total synthesis of (-)-erogorgiaene and its C11 epimer and investigation of their antimycobacterial activity

A short, nine-step, highly enantioselective synthesis of (−)-erogorgiaene and its C-11 epimer is reported. The key stereochemistry controlling steps involve catalytic asymmetric crotylation, anionic oxy-Cope rearrangement and cationic cyclisation. (−)-Erogorgiaene exhibited promising antitubercular activity against multidrug-resistant strains of Mycobacterium tuberculosis