Synthesis of solamin type mono-THF acetogenins using cross-metathesis

The total synthesis of mono-THF acetogenins, cis-solamin A and B, and reticulatacin, was accomplished starting with muricatacin. The backbone of the mono-THF acetogenins was constructed by olefin cross-metathesis between the tetrahydrofuran moiety and γ-lactone moiety. An enzymatic kinetic transesterification procedure was successfully applied to the synthesis of an optically pure γ-lactone moiety. Notably, cis-THF compounds were obtained without using protective groups.     

Synthesis of pyrrolidine analogues of solamin

A convergent synthesis of pyrrolidine analogues of solamin, which possessed a pyrrolidine in place of the tetrahydrofuran ring, was presented in a facile route from 2,5-trans-bis(methoxycarbonyl)pyrrolidine. The stereochemistry of pyrrolidine core unit was determined by ¹H NMR spectroscopic analysis.     

Total synthesis of cis-solamin A, a mono-tetrahydrofuran acetogenin isolated from Annona muricata

Total synthesis of cis-solamin A was accomplished without using protecting groups starting from (−)-muricatacin in 11 steps with an overall yield of 4.5%. The backbone of cis-solamin A was constructed by olefin cross-metathesis between the tetrahydrofuran moiety and γ-lactone moiety. An enzymatic kinetic transesterification procedure was successfully applied to the synthesis of an optically pure γ-lactone moiety.