Irradiation of two steroidal α-azido ketones gave N-acyl imines by formal acyl migration onto nitrogen. Spectroscopic characteristics (u.v., i.r., 1H n.m.r., and 13C n.m.r.) and chemistry of these is described. Similarly an α-azido γ-lactone gave a 5,6-dihydro-1,3-oxazin-2-one which added methanol readily to give a 4-methoxytetrahydro-1,3-oxazine-2-one. Possible mechanisms are considered for the observed rearrangements.