The synthesis of a number of 22, 26-epiminocholestanes and 22, 26-epiminocholest-22(N)-enes, and the assignment of their I3C n.m.r. spectra are described. The 13C n.m.r. spectra of the new 3β-amino steroidal alkaloids solacallinidine (12a) and soladunalinidine (11d), and some derivatives, are also assigned and the previously described spectra of the known 3β-amino alkaloids solanocapsine (13) and jurubidine (15) are reassigned. The assignments are based on deuterium labelling, paramagnetic broadening, chemical shift considerations and off-resonance decoupling. © 1979, CSIRO. All rights reserved.