Anthraquinones of Damnacanthus indicus

Abstract A new anthraquinone, 5-hydroxy-1,2-methylenedioxyanthraquinone, along with three known anthraquinones, damnacanthal, juzunol, and damnacanthol, and four artificial anthraquinones were isolated from the rhizomes of Damnacanthus indicus grown in Japan. The new anthraquinone was characterized as 5-hydroxy-1,2-methylenedioxyanthraquinone by comparison its methyl ether with synthetic 5-methoxy-1,2-methylenedioxyanthraquinone.