New cytotoxic isoflavone from the root bark of Brosimum utile.

A new isoflavone 5,7,4'-trihydroxy-3'-(3-hydroxy-3-methylbutyl)isoflavone (isowigtheone hydrate) (1), together with six known isoflavones 2-7 and (-)epicatechin, were isolated from the root barks of Brosimum utile. Their structures were established on the basis of spectroscopic evidence. The in vitro cytotoxic activity of the new compound 1 was evaluated against cell lines MCF7 (human breast carcinoma), PC3 (human prostate carcinoma), HT29 (human colon cancer) and human dermis fibroblasts.