New Triterpenic Saponins from Cephalaria transsylvanica

Three new triterpenic saponins, 3-O-[b-D-xylopyranosyl (1 \to 4)-b-D-glucopyranosyl (1 \to 4)-b-D-glucopyranosyl (1 \to 3)-a-L-rhamnopyranosyl (1 \to 4)-b-D-xylopyranosyl] hederagenin 28-O-[b-D-glucopy\-ranosyl (1 \to 4)-b-D-glucopyranosyl] ester (1), 3-O-[b-D-glucopyranosyl (1 \to 4)-b-D-glucopyranosyl (1 \to 3)-a-L-rhamnopyranosyl (1 \to 4)-b-D-xylopyranosyl] hederagenin 28-O-[b -D-glucopyranosyl] ester (2) and 3-O-[b-D-glucopyranosyl (1 \to 3)-a-L-rhamnopyranosyl (1 \to 4)-b-D-xylopyranosyl] hederagenin(3) were isolated from Cephalaria transsylvanica. After cleavage of the ester-glycosidic linkage of the bisdesmosidic compounds, two new prosapogenins, 3-O-[b-D-xylopyranosyl (1 \to 4)-b-D-glucpyranosyl (1 \to 4)-b-D-glucopyranosyl (1 \to 3)-a-L-rhamnopyranosyl (1 \to 4)-b-D-xylopyranosyl] hederagenin (4) and 3-O-[b-D-glucopyranosyl (1 \to 4)- b-D-glucopyranosyl (1 \to 3)-a-L-rhamnopyranosyl (1 \to 4)-b-D-xylopyranosyl] hederagenin (5) were also isolated. The structures of the compounds were established by chemical and spectroscopic means.