New flavonoid glycosides from Vernonia ferruginea.

Four new flavonoid glycosides, quercetin 3-O-beta-D-xylopyranosyl-(1-4)-beta-D-glucopyranoside, quercetin 3-O-beta-D-apiofuranosyl-(1-4)-beta-D-glucopyranoside, kaempferol 3-O-beta-D-apiofuranosyl-(1-4)-beta-D-glucopyranoside, and kaempferol 4'-methyl ether 3-O-beta-D-xylopyranoside, along with other known flavonoids and phenolic derivatives, were isolated from the leaves of Vernonia ferruginea Less. Their structures were established on the basis of detailed spectral analysis.