Enantioselective total synthesis of the marine toxin (-)-gymnodimine employing a barbier-type macrocyclization

Abstract

Sea the synthesis: At ambient temperature, tertbutyllithium promotes a Barbier-type macrocyclization in the first total synthesis of (-)-gymnodimine (Ts: toluene-4- sulfonyl; TBS: tert-butyldimethylsilyl), a member of the spirocyclic-imine family of marine toxins. The synthesis also features a vinylogous Mukaiyama aldol process to couple the labile butenolide moiety onto a macrocyclic ketone intermediate. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.