抄録
A new steroidal sapogenin isolated from Heloniopsis orientalis (THUNB.) C. TANAKA was named “heloniogenin”. The chromic acid oxidation of this sapogenin yielded gentrogenin. Gentrogenin acetate was also obtained with the chromic acid oxidation heloniogenin 3-acetate. Of two isomers derived from gentrogenin with the metal hydride reduction, 3β, 12α-diol was identified with heloniogenin. The structure of heloniogenin was confirmed as 25D-spirost-5-ene-3β, 12α-diol.