A major triterpenoid saponin from Gypsophila oldhamiana

A new saponin, gypoldoside A (1), was isolated from the roots of Gypsophila oldhamiana. On the basis of in-depth NMR-spectroscopic and mass-spectrometric analysis, in combination with chemical evidence, its structure was established as 3-O-{beta-D-galactopyranosyl-(1-2)-(1 -> 2)-[beta-D-xylopyranosyl-(1 -> 3)]-beta-D-glucuronopyranosyl}quillaic acid 28-[alpha-L-arabinopyranosyl-(1 -> 2)-alpha-L-arabinopyranosyl-(1 -> 3)-beta-D-xylopyranosyl-(1 -> 4)-alpha-L-rhamnopyranosyl-(1 -> 2)-beta-D-fucopyranosyl] ester. Compound 1 was found to be highly active against three different human cancer cell lines, with IC50, values in the low micromolar range.