Chemical constituents from ethyl acetate extract of Cynanchum otophyllum Schneid.

Fourteen compounds were isolated and purified from ethyl acetate extract of Cynanchum otophyllum Schneid. , and were identified as otophylloside A( 1 ), otophylloside B( 2 ), 2, 5-dihydroxyacetophenone( 3 ), methyl 2, 5-dihydroxy-benzoate( 4 ), vanillin( 5 ), arjunolic acid( 6 ), glycosmisic acid( 7 ), caudatin-3-O-β-D- cymaropyranosyl-(1→4)-β-D-oleandropyranosl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside( 8 ), penupogenin( 9 ), caudatin-3-O-β-D-glucopyranosyl-(1 →4)-β-D-oleandropyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside( 10 ), qingyangshengenin-3-O-β-D-oleandropyranosyl-(1→4)-β-D- cymaropyranosyl-(1→4)-β-D-digitoxopyranoside( 11 ), and kidjoranin-3-O-β-D- cymaropyranoside( 12 ), qingyangshengenin-3-O-β-D-cymaropyranosyl-(1→4)-β-D- digitoxopyranoside( 13 ), and kidjoranin-3-O-β-D-oleandropyranosyl-(1→4)-β-D- cymaropyranosyl-(1→4)-β-D-cymaropyranoside( 14 )by physicochemical properties and spectroscopic analyses. Among them, compounds 6-7 were firstly isolated from the genus Cynanchum, and compounds 3-5, 8-14 were isolated from this plant for the first time.