From the total alkaloids isolated by chloroform extraction of the epigeal part of Rhinopetalum stenantherum a new base has been isolated - stenanzine - with mp 203-205°C, [α]D-44°, C27H43NO3. On the basis of a study of the IR, NMR, and mass spectra of stenanzine and its conversion products the configuration and structure of 3β,23α-dihydroxy-5α-veratr-12-enin-6-one have been established for this alkaloid. © 1983 Plenum Publishing Corporation.