An efficient synthesis of the C27-C45 fragment of lagunamide A, a cyclodepsipeptide with potent cytotoxic and antimalarial properties

Abstract

An efficient and stereoselective synthesis of the entire C27-C45 moiety of lagunamide A has been achieved from 1-[(4S)-4-benzyl-2-thioxothiazolidin-3-yl]propan-1-one in six steps with 22% overall yield. The key step in the synthesis is an asymmetric acetal aldol reaction featuring the enantioselective addition of a chiral thiazolidinethione-derived titanium enolate to an acetal to establish the stereochemistry at C39. (C) 2013 Elsevier Ltd. All rights reserved.