Synthesis of the Racemate of the Stereoisomer at C-6a of BE-40644, a Bioactive Metabolite of Actinoplanes sp. with a Sesquiterpene-substituted p-Benzoquinone Structure

Abstract

BE-40644 is a tetracyclic metabolite of Actinoplanes sp. A 40644 possessing a sesquiterpene-substituted p-benzoquinone structure with cis-fused B/C ring stereochemistry that inhibits the human thioredoxin system as the well as the growth of several cancer cell lines. Its B/C trans-fused stereoisomer at C-6a was synthesized as a racemate starting from geranylacetone and 3,5-dihydroxybenzoic acid.