Triterpenoid Saponins from Anemone flaccida.

From the rhizome of ANEMONE FLACCIDA Fr. Schmidt, used in Chinese folk medicine, four saponins of oleanolic acid-A,B,C,D were isolated. By means of spectroscopy and chemical transformation, saponins A, B, and D were identified as 3- O-[alpha- L-rhamnopyranosyl-(1-->2)-alpha- L-arabinopyrasyl]-oleanolic acid, 3- O-[alpha- L-rhamnopyranosyl-(1-->2)-beta- D-xylopyranosyl]-oleanolic acid, and 3- O-[alpha- L-rhamnopyranosyl-(1-->2)-beta- D-glucopyranosyl]-oleanolic acid. These three saponins are known compounds but isolated from ANEMONE plants for the first time. Saponin C was elucidated as 3- O-[beta- D-glucopyranosyl-(1-->2)-beta- D-xylopyranosy1]-oleanolic acid, which has not been reported in the literature before, and is named as flaccidoside I.