Abstract: Two epimers of triterpenoid saponins, kajiichigoside F1 (R-8) and rosamultin (R-9) were isolated from the fruits of Rosa roxburghii Tratt. R-8 was obtained as white needle crystal with mp 205–207℃ and [a]D18 + 10.5˚ (C = 0.0953, absolute ethanol); R-9 was white crystal with mp 214–216℃ and [a]D18 + 9.5 (C=0.1050, absolute ethanol). The structures of the two compounds were elucidated on the basis of spectroscopic analysis ,(UV, IR, 1H-, 13C-NMR, MS) and chemical methods.

Key words: Rosa roxburghli Tratt, Triterpenoid saponin, Epimeride