From roots of Rubia cordifolia L. four anthraquinones are isolated: 1-hydroxy 2-methoxy anthraquinone; 1,4-dihydroxy 2-methyl 5-methoxy anthraquinone or 1,4-dihydroxy 2-methyl 8-methoxy anthraquinone; 1,3-dimethoxy 2-carboxy anthraquinone and rubiadin.