Flavonoid constituents and biological screening of Astragalus bombycinus Boiss.

Two new flavonoid compounds were isolated from Astragalus bombycinus Boiss. and identified as quercetin-3,7-di-O-β-glucopyranoside 4'-O-α-rhamnopyranoside and 5,2',4'-trihydroxy-flavone-8-C-α-arabinopyranoside-7-O-β-glucopyranoside. In addition, apigenin, apigenin-7-O-β-glucopyranoside, apigenin 7-O-gentobioside, luteolin, luteolin-7-O-β-glucopyranoside, quercetin-3,7-di-O-β-glucopyranoside, quercetin-3-O-β-glucopyranoside-7-O-α-rhamnopyranoside and daidzein were also isolated and identified.

A new kaempferol triglycoside from Fagonia taeckholmiana: cytotoxic activity of its extracts.

In addition to apigenin, apigenin 7-O-glucoside, kaempferol 3-O-glucoside, kaempferol 3,7-di-O-rhamnoside, quercetin, and quercetin 3-O-glucoside, the methanolic extract of Fagonia taeckholmiana afforded a new compound identified as kaempferol 3-O-beta-l-arabinopyranosyl-(1-->4)-alpha-l-rhamnopyranoside-7-O-alpha-l-rhamnopyranoside. Identification of the isolated compounds was based on chemical and spectroscopic analyses including UV, FABMS, (1)H, (13)C and 2D NMR, and DEPT. The cytotoxic activities of the compounds against several cancer cell lines were determined.