Total synthesis and absolute configuration of malyngamide W

Abstract

A concise enantioselective synthesis of malyngamide W (1) and its 2′-epimer was described. The strategy was based on three key steps: (1) ozonolysis of compound 11 which was derived from (R)-(−)-carvone 8, followed by copper-iron-catalyzed rearrangement to give the key cyclohex-2-enone intermediate 5, (2) Nozaki–Hiyama–Kishi coupling reaction between aldehyde 4 and iodide 14 to afford alcohol 3, and (3) asymmetric (R)-CBS reduction of the ketone functionality in compound 21 to establish the C-2′ chiral center in the target compound 1. The absolute configuration of malyngamide W (1) was thus confirmed via the synthesis of 1 and 2′-epi-1.