T. Inoue et al., STEROIDAL SAPONINS FROM THE TUBERS OF DICHELOSTEMMA-MULTIFLORUM AND THEIR INHIBITORY ACTIVITY ON CYCLIC-AMP PHOSPHODIESTERASE, Phytochemistry, 39(5), 1995, pp. 1103-1110
Phytochemical examination of the tubers of Dichelostemma multiflorum l
ed to the isolation of three new steroidal saponins together with two
known saponins. The structures of the new compounds were determined by
spectral data and a few chemical transformations to be (25R)-S alpha-
spirostane-1 beta,3 beta-diol (brisbagenin) 1-O-{O-alpha-L-rhamnopyran
osyl-(1 --> 3)-4-O-acetyl-alpha-L-arabinopyranoside}, brisbagenin 1-O-
{O-alpha-L-rhamnopyranosyl-(1 --> 2)-O-[alpha-L-rhamnopyranosyl-(1 -->
3)]-4-O-acetyl-alpha-L-arabinopyranoside} and (22S,25S)-5 alpha-spiro
stan-3 beta-ol 3-O-{O-beta-D-galactopyranosyl-(1 --> 2)-O-[beta-D-xylo
pyranosyl-(1 --> 3)]-O-beta-D-glucopyranosyl-(1 --> 4)-beta-D-galactop
yranoside}. The known compounds were identified as desglucolanatigonin
II and gitonin, with certain amounts of the corresponding C-25S isome
rs. Inhibitory activity of the isolated saponins and their derivatives
on cAMP phosphodiesterase was evaluated to identify new compounds wit
h medicinal potential.