Soyasaponin Bh, a triterpene saponin containing a unique hemiacetal-functional five-membered ring from Glycine max (soybeans).

Soybeans (Glycine max L. Merill) and soy-based food products are major dietary sources of saponins. An oleanane triterpenoid saponin, soyasaponin Bh (1) containing a unique five-membered ring with a hemiacetal functionality together with seven known saponins were isolated from soybeans. Their structures were determined by chemical and spectroscopic analyses including HR-ESI-MS, 1D- and 2D-NMR. None of the isolated saponins showed any anti-cell proliferative activity in tumor cell lines. Soysaponin I showed a weak estrogenic effect in the yeast estrogen screen (YES) assay.