The results of the photolysis of five steroidal 6-membered cyclic α-nitro ketones in ethanol are described. Irradiation with a Pyrex-filtered light of 2-nitro-5α-cholestan-3-one in ethanol, which exists exclusively in the enol form in the solvent, resulted in a new photorearrangement and gave 5α-cholestane-2,3-dione 3-oxime with the accompanying formation of the corresponding α-diketone. We propose