Spirostanol sapogenins from the underground parts of Tupistra chinensis.

Chemical examination of the underground parts of Tupistra chinensis led to the isolation of two new 5beta-spirostane type steroidal sapogenins, tupichigenin B (1) and C (2), together with two known steroidal sapogenins, ranmogenin A (3) and delta25(27)-pentrogenin (4). The structures of 1 and 2 were established as spirost-25(27)-ene-1beta,3beta,4beta,5beta,6b eta-pentaol and 1beta,2beta,3beta,4beta,5beta-pentahydroxyspi rost-25(27)-en-6-one, respectively, on the basis of detailed analysis of their physical and spectral data.