Studies on anthraquinones from the roots of rubia cordifolia l

Seven anthraquinones were isolated from the ethyl alcohol extracts of the roots ofRubia Cordifolia L.. By means of spectrometric data combined with physico-chemical properties, six ofthem wewre identified as 2-methyl-1, 3, 6-trihydroxy-9,10-anthraquinone (Ⅰ), 1-hydroxy-9, 10-anthraquinone (Ⅱ), 1, 2,4-trihydroxy-9, 1 0-anthrequinone (Ⅲ), 2-methyl-1, 3, 6-trihydroxy-9, 10-anthraquinone-3-O-β-D-glucoside(Ⅳ), 1, 2-dijhydroxy-9, 10-anthraquinone-2-O-β-D-xylosyl (1→6)-β-D-glucoside (Ⅴ) and 1,3-dihydroxy-2-hydroxymethy 1-9, 10-anthraquinone-3-O-β-D-xylosyl(1→6)-β-D-glucoside(Ⅵ). Ⅶ is a new compound. Its structure was elucidated to be 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-β-D-xylosyl (1→2)-β-D-(6'-O-acetyl)glucoside.