Aim: To investigate the chemical constituents of the roots of Pulsatilla cernua (Thunb.) Bercht. et Opiz.
Methods: Column chromatography (including D101 macroporous resin, silica gel and ODS) and HPLC were used to separate the chemical constituents whose structures were elucidated by FAB-MS, NMR (1D and 2D) and hydrolysis methods.
Results: Six compounds were isolated and established as hederagenin 3-O-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranoside (pulsatilla saponin A, 1), hederagenin 3-O-beta-D-glucopyranosyl (1-->3)-alpha-L-rhamnopyranosyl (1-->2)-alpha-L- arabinopyranoside (2), hederagenin' 3-O-alpha-L-rhamnopyranosyl(1-->2)[beta-D- glucopyranosyl(1-->4)]-alpha-L-arabinopyranoside (pulsatilla saponin D, 3), 3-O-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl ester (dipsacoside B, 4), 3-O-alpha-L-rhamnopyranosyl(1-->2) [beta-D-glucopyranosyl(1-->4)]-alpha-L-arabinopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (cernuoside C, 5) and daucosterol (6), respectively.
Conclusion: Compound 5 is a new compound and named as cernuoside C. Compounds 2, 4 and 6 were isolated from Pulsatilla cernua for the first time.