Saponins from Fagonia glutinosa.

Twelve triterpenoid saponins, including six new, were isolated and identified from the aerial parts of Fagonia glutinosa. The new saponins were characterised as 3-O-[β-D-glucopyranosyl(1→2)][β-D-glucopyranosyl(1→3)]-α-L-ara-binopyranosyl-27-hydroxy oleanolic acid 28-O-β-D--glucopyranosyl ester, 3-O-[β-D-glucopyranosyl(1→3)]-α-L-arabinopyranosyl ursolic acid, 3-O-α-L-arabinopyranosyl ursolic acid 28-O-β-D-glucopyranosyl ester, 3-O-[β-D-xylopyranosyl(1→2)][β-D-glucopyranosyl(1→3)]-α-L-arabinopyranosyl ursolic acid, 3-O-[β-D-glucopyranosyl(1→2)][β-D-glucopyranosyl(1→3)]-α-L-arbinopyranosyl ursolic acid 28-O-β-D-glucopyranosyl ester and 3-O-[β-D-glucopyrano-syl(1→2)][β-D-glucopyranosyl(1→3)]-α-L-arabinopyranosyl-27-hydroxy ursolic acid 28-O-β-D-glucopyranosyl ester. The structures of the saponins were established by spectral and chemical evidences. The assignments of the NMR signals were performed by means of HOHAHA, 1 H- 1 H COSY, ROE, HMQC and HMBC experiments.