New Calycosin Glycosides from Astragalus mongholicus

Two new isoflavone glycosides 1 and 2 were isolated from roots of Astragalus mongholicus Bunge (A. membranaceus Fisch. ex Bunge, Fabaceae). The compounds were calycosin 7-O-(2′′-O-β-Dglucopyranosyl)-β-D-glucopyranoside (astramonghoside A, 1) and calycosin 7-O-(2′′-O-β-D-glucopyranosyl-6′′-O-malonyl)-β-D-glucopyranoside (astramonghoside B, 2) according to UV and NMR spectroscopy and mass spectrometry. Compounds 1 and 2 inhibited fungal tyrosinase.