Abstract: Two new triterpenoid saponins, namely prostratoside D and E, were isolated from the whole plants of Polycarpon prostratum (Forssk.)Aschers. et Schwein. ex Aschers.By spectroscopic methods, their structures were determined as 3-O-{β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→2)]-a-L-arabinopyranoside}-saikogeninD和3-O-{β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranoside}-saikogenin G,respectively.

Key words: Polycarpon prostratum