Studies on the constituents of Xanthoceras sorbifolia Bunge. II. Major sapogenol and a prosapogenin from the fruits of Xanthoceras sorbifolia Bunge.

The main sapogenol and a prosapogenin from the fruits of Xanthoceras sorbifolia BUNGE (Sapindaceae) were examined. On the basis of chemical and spectral analyses, the structure of the new sapogenol obtained by acid hydrolysis of crude saponin fraction was established to be 21β, 22α-diangeloyloxy-3β, 15α, 16α, 28-tetrahydroxyolean-12-ene (=21, 22-di-O-angeloyl-R1-bar-rigenol) (1). The structure of the prosapogenin was identified as 21β-(3, 4-di-O-angeloyl-β-D-fucopyranosyl) oxy-3β, 16α, 22α, 24, 28-pentahydroxyolean-12-ene (napoleogenin B) (6) on the basis of spectral and X-ray crystal diffraction analyses.