Isoflavonoids from roots of Astragalus membranaceus var. mongholicus

To study the isoflavonoid constituents of the roots of Astragalus membranaceus var. mongholicus.Such column chromatography methods as HPD-100 macroporous adsorption resin, silica gel, polyamide and Sephadex LH-20 gel were used for seperating and purifying isoflavonoids, and their structures were identified on the basis of spectral data.Fourteen compounds were separated and identified as: formononetin (1), ononin (2) calycosin (3), calycosin-7-O-beta-3-D-glucopyranoside (4), (6aR, 11aR)-3-hydroxy-9,10-dimethoxypterocarpan (5), (6aR, 11aR)-3-hydroxy-9,10-dimethoxypterocarpan-3-O-beta-D-glucopyranoside (6), (3R) -7,2'-dihydroxy-3', 4'-dimethoxyisoflavan (7), (3R) -7, 2'-dihydroxy-3', 4'-dimethoxyisoflavan-7-O-beta-D-glucopyranoside (8), 6"-O-acetyl-ononin (9), 6"-O-acetyl-(3R) -7, 2'-dihydroxy-3', 4'-dimethoxyisoflavan-7-O-beta-D-glucopyranoside (10), 6"-O-acetyl-(6aR, 11aR)-3-hydroxy-9, 10-dimethoxypterocarpan-3-O-beta-D-glucopyranoside (11), pratensein (12), sissotrin (13) and 5,7,4'-trihydroxy-3'-methoxyisoflavone (14).Compound 10 was a new compound. Compounds 9, 11, 13,14 were separated from A. membranaceus var. mongholicus for the first time.