A new protopanaxadiol-type ginsenoside from the roots of Panax notoginseng.

A new protopanaxadiol-type ginsenoside, 6-O-β-d-glucopyranosyl-20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol-3-one (1), along with three known compounds, was isolated from the roots of Panax notoginseng. Their structures were determined based on some pieces of spectroscopic and chemical evidence. Compound 1 exhibited cytotoxic activity against five human cancer cell lines, with IC50 values ranging from 5.4 to 8.6 μg/ml.