Triterpene saponins from Gynostemma cardiospermum

Six new dammarane glycosides (1-6) and four known compounds, rutin, kaempferol, quercetin, and linalool 3-O-beta-D-glucopyranoside, were isolated from an ethanol extract of the aerial parts of Gynostemma cardiospermum. The structures of 1-6 were elucidated by 1D and 2D NMR spectroscopic interpretation as well as by chemical degradation. Triterpene aglycons containing carbonyl groups at both C-21 and C-28, as found in compounds 1-5, are being reported in the family Cucurbitaceae for the first time.