Cytotoxic prenylated flavonoids from Morus alba.

A phytochemical fractionation of the methanol extract of the Morus alba leaves led to the isolation of eleven flavonoids (1-11). The structure of the new 3'-geranyl-3-prenyl-2',4',5,7-tetrahydroxyflavone (1) was elucidated by means of spectroscopic methods. The cytotoxicity of the isolated compounds against human cervical carcinoma HeLa, human breast carcinoma MCF-7, and human hepatocarcinoma Hep3B cells was evaluated. Of note, morusin (9) was the most potent with an IC(50) value of 0.64 μM against HeLa cells.