Damarane-type Saponins from Gynostemma Longipes and their Cytotoxic Activity

Two new damarane- type saponins, named gylongiposides II-III (1 and 2), along with one known compound, (23 S)-3β,20ζ,21ζ-trihydroxy-19-oxo-21,23-epoxydammar-24-ene 3- O-α-L-rhamnopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-α-L-arabinopyranoside, were isolated from the leaves of Gynostemma longipes C.Y.Wu. Their structures were determined by 1D- and 2D-NMR and HR-ESI-MS spectra. Compounds 1–3 exhibited moderate activity against four human cancer cell lines, A-549, HT-29, OVCAR, and MCF-7, with IC 50 values ranging from 9.8 ± 2.1 to 49.6 ± 2.6 μM.