Triterpenoid Saponins from the Fruits of Symplocos lucida as ß-Glucuronidase Inhibitors.

A new triterpenoid saponin and five known ones were isolated from the fruits of Symplocos lucida (Thunb.) Siebold & Zucc. Their structures were determined based on the results of spectroscopy analysis, chemical conversions, and X-ray crystallographic analyses. The ß-glucuronidase-inhibitory effects of the isolated and semi-synthesized triterpenoid saponins were also examined.