PRENYLATED ISOFLAVANONE FROM ERYTHRINA-ERIOTRICHA

Bioassay-directed fractionation of a methylene chloride extract of the root bark of Erythrina eriotricha resulted in the isolation of a nove l isoflavanone, named eriotrichin B, and the five known pterocarpans, isoneorautenol, erybraedin A, erybraedin C, erybraedin D and erybraedi n E. The structure of the new compound has been investigated by extens ive spectroscopic studies, including 2D NMR and chemical evidence. The in vitro antimicrobial spectrum and potencies of the isolated compoun ds are also reported.