Four anthraquinones from Hedyotis diffusa

A new anthraquinone has been isolated from the 95% EtOH extract of Hedyotis diffusa and characterized as 2-hydroxy-3-methoxy-6-methyl-9,10-anthraquinone (1) by extensive spectral analysis. The known compounds isolated for the first time from this plant have been identified as 2-hydroxy-3-methoxy-7-methyl-9,10-anthraquinone (2), 2-hydroxy-6-methylanthraquinone (3), and 1,3-dimethoxy-2-hydroxy-9,10-anthraquinone (4).