New quassinoids from indonesian Picrasma javanica. Structures of javanicins E, F, G and M.

Abstract

Four new des-4-methylated picrasane type quassinoids, javanicins E, F, G and M, were isolated from the bark of Indonesian Picrasma javanica (Simaroubaceae). In addition, the known quassinoid, quassin, was also identified. The structures were determined by spectroscopic data and chemical evidence.