THE STRUCTURE OF ASTRACHRYSOSID A AND THE STUDY OF 2D-NMR ON ASTRASIEVERSIANIN XV AND 7, 2'-DIHYDROXY-3',4'-DIMETHOXY- ISOFLAVANE-7-O-β-D-GLYCOSIDE

Six compouns were isolated from the root of Astragalus chrysopterus Bunge. One of them was identified as a new triterpenoid glycoside, named astrachrysoside A. Its structure was elucidated as 3-O-α-L-rhamnopyranosyl (1→2) β-D-xylopyranosyl-cycloastragenol on the basis of physicochemical evidence and chemical reactions The others were shown to be known compounds, astrasieversianin ⅩⅤ (Ⅱ),7,2'-dihydroxy-3',4'-dimethoxy -isoflavane-7-O-β-D-glucoside (Ⅲ), soyasaponin Ⅰ, daucosterol and β-sitosterol. Full assignment of the chemical shift signals of Ⅱ and Ⅲ were estab-lished by various 2D-NMR techniques.