Four new phenolic constituents from the roots of Rumex dentatus L.

Four new phenolic compounds, including two naphthalenes, musizin-8-O-β-D-(6'-O-malonyl-3''-methoxy)glucopyranoside (1) and 2-acetyl-3-methyl-1,4-naphtho-quinone-8-O-β-D-glucopyranoside (2), one chromone, (2'R)-7-hydroxy-2-(2'-hydroxypropyl)-5-methyl acetate chromone (3), and one xanthone, 2,8-dimethyl-3,6-dihydroxyxanthone (4) were isolated from the roots of Rumex dentatus L. (Polygonaceae). In addition, five known including four naphthalenes (5-8) and one chromone (9) were also obtained. Their structures were determined by means of extensive spectroscopic analysis and acidic hydrolysis. Compound 1 showed moderate antifungal activity against Epidermophyton floccosum, with inhibitory rate of 39.539 ± 0.412% at a concentration of 100 μM.