Steroid saponins from Solanum laxum.

Two new steroid saponins, named laxumins A and B, were isolated from the ethanolic extract of the aerial parts of Solanum laxum. These compounds were characterized, using mainly NMR spectroscopy, mass spectrometry and chemical methods, as (23S,25S)-spirost-5-en-3 beta, 15 alpha, 23-triol 3-O-{beta-D-glucopyranosyl-(1-->2)- beta-D-glucopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D- galactopyranoside} and 3-O-{beta-D-glucopyranosyl-(1--> 4)-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-galactopyranoside}, respectively.