3-Hydroxy-1,2-dimethoxy-anthraquinone

Anthragallol 1,2-dimethyl ether (compound 11) can be isolated from O. umbellata. Anthragallol 1,2-dimethyl ether has cytotoxicity, with IC50 values of 5.9 and 8.8 μg/ml against A549 cells and MDA-MB-231 cells, respectively.