Summary. The photo-oxidation of the title compound (1) is described. The isolated productsIn recent times, the photo-oxidation of the enamine function has received considerable attention [Zj. These compounds suffer [Z + 21 siglet oxygen addition, with formation of unstable l,Z-dioxetanes, that ultimately yield carbonylic fragments. The decomposition of these dioxetanes are usually accompanied by luminiscence phenomena. On the other hand, oxidation products of enamides seem to play an important role in bioluminiscence phenomena [3]. For all this and considering the photoreactivity of the 4 5 double bond in compound 1 [l], it was thought of interest to study its bchaviour in photo-oxidation conditions. When 1, easily obtained from testosterone acetate [4], was irradiated during 12 h in benzene (Merck, analytical purity), with the light of a low-pressure Hg lamp, under a current of oxygen, a mixture of compounds was obtained, containing starting material (1, !I%), the hydroxy derivative 2 (5%), the diol 3 (16%), the dioxetane 4 (5%) and the keto-alcohol 5 (30%) (Scheme 7). All the structures were assigned on basis of the corresponding spectroscopic and analytical dataz). Scheme 1are the result of a [2+ 21 oxygen addition to the olefinic double bond of the cnamide.

Die Photooxidation des Azasteroids (I) in Benzol verläuft unter [2 + 2]‐Saue stoffaddition an die Enamid‐Bindung zu den Produkten (II), (III) und (IVa).