Abstract: To investigate saponins from the roots of Pulsatilla cernua (Thunb.) Bercht. et Opiz., two new compounds together with five known triterpenoid saponins were isolated. The structures of the two new triterpenoid saponins, named cernuasides A and B, were elucidated as 3-O-[β-D-xylopyranosyl(1→2)]-[α-L-rhamnopyranosyl(1→4)]-α-Larabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester (compound 1) and 3-O-[α-L-arabinopyranosyl(1→3)]-[α-L-rhamnopyranosyl (1→2)]-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester (compound 2) by 1D, 2D-NMR techniques, ESIMS analysis, as well as chemical methods.

Key words: cernuasides A and B, Pulsatilla cernua, Ranunculaceae, triterpenoid saponin.