Chemoenzymatic approach to the total synthesis of (+)-bourgeanic acid

Abstract

A highly stereoselective total synthesis of (+)-bourgeanic acid has been accomplished by an enzymatic desymmetrization approach to create two methyl chiral centers. Other key steps involved in this approach are a Wittig reaction, a Gilman reaction, and TEMPO/iodobenzene diacetate mediated selective oxidation of the 1,3-diol, Yamaguchi lactonization and lithium hydroxide mediated partial hydrolysis (saponification) of the eight-membered cyclic dilactone. © Georg Thieme Verlag Stuttgart · New York.