Three undescribed monoterpene rhamnosides from the aerial parts of Vangueria agrestis

Phytochemical investigation of the methanolic extract of Vangueria agrestis aerial parts led to the isolation and characterization of four monoterpene rhamnosides, two ursane saponins, and six flavonoid glycosides. Of these constituents, are three undescribed monoterpene glycosides, vangagrestosides A-C. The reported constituents comprise the monoterpene glycoside [(2E,6Z)-2,6-dimethyl-8-[O-alpha-L-rhamnopyranosyl-(1-->3)-alpha-L-rhamnopyranosy l)-oxy]-octadien-1-yl alpha-L-rhamnopyranoside], the saponins [3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]pomolic acid, and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl]pomolic acid], and the flavonoids [narcissoside, rutin, hyperoside, guajavarin, biorobin, and nicotifloroside].