Prenylated stilbenes and flavonoids from the leaves of Cajanus cajan

Three new prenylated stilbenes, named as cajanusins A-C ( 1-3 ), and one new natural product cajanusin D ( 4 ), along with six known derivatives ( 5-10 ) were isolated from the leaves of Cajanus cajan. Their structures were fully elucidated by means of extensive spectroscopic methods and comparison with data in the reported literatures. The new compounds of 1 and 2 were evaluated for in vitro cytotoxic activities against a panel of human cancer cell lines.