Total Synthesis and Structural Revision of (-)-Sodagnitin E.

Abstract

We report the total synthesis of malabaricane triterpene sodagnitin E, marking the first synthesis of any malabaricane natural product to date. The enantioselective synthesis of two key fragments, followed by their coupling via a Mukaiyama aldol reaction delivered the triterpene framework in a convergent synthesis. A thorough analysis of the synthetic material led to the elucidation of a previously unassigned stereocenter (C17) as well as the reassignment of the configuration at C27. This enabled the structural revision of the relative configuration at the central lactol moiety.