A novel dimeric flavonol glycoside from subsp. .

A novel dimeric flavonol glycoside, Cynanflavoside A (), together with six analogues, kaempferol-3---L-rhamnopyranosyl-(1→2)--D-glucopyranoside (), quercetin-3---L-rhamnopyranosyl-(1→2)--D-glucopyranoside (), kaempferol-3---L-rhamnopyranosyl-(1→2)--D-xylopyranoside (), quercetin-3---L-rhamnopyranosyl-(1→2)--D-xylopyranoside , kaempferol-3---D-glucopyranosyl-7---L-rhamnopyranoside (), and quercetin-3--galactoside () were isolated from the -butyl alcohol extract of subsp. . Their structures were determined spectroscopically and compared with previously reported spectral data. All compounds were evaluated for their anti-complementary activity , and only compound exhibited anti-complement effects with CH value of 0.33 mM.