The alkaloids imperialine, imperialone, peumisine, petiline, petilidine, and the new bases petisine (I) and petisinine (III) have been isolated from bulbs of Petilium raddeana (Regl.) Vved. On the basis of spectral characteristics and passages to a known compound, the structure of 3β-hydroxy-Δ22(N)-22,26-iminocholestane-6,23-dione has been established for (I) and petisine 3β-glucopyranoside for (III). © 1982 Plenum Publishing Corporation.