A new prenylated acetophenone from the root bark of Derris indica.

A new acetophenone, 1-[2,4-dihydroxy-5-(3-methylbut-2-enyl)phenyl]ethanone (1) was isolated from the root bark of Derris indica, along with 3,7,-dimethoxy-3',4'-methylenedioxyflavone (desmethoxykanugin) (2), 5-methoxyfurano[4",5":6,7]flavone (pinnatin) (3), and 3'-hydroxyfurano[4",5":7,8]flavone (pongol) (4). The structures of these compounds were established by means of chemical and spectral studies. The occurrence of this prenylated acetophenone in D. indica is of biogenetic and chemotaxonomic significance.