Triterpene saponins from Clematis mandshurica and their antiproliferative activity.

Six new triterpene saponins, clematomandshurica saponins F-K (1-6), together with a known compound (7), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis. Compounds 5-7 exhibited antiproliferative effects against PC-3 human prostate cancer cells with GI50 values of 1.29, 1.50, and 0.71 µM, respectively. Georg Thieme Verlag KG Stuttgart · New York.