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.

Dedicated to Professor Oskar Jeger on his 60th anniversary (2.11.78) SummaryThe irradiation of 17/j'-acetoxy-4-oxa-l, 5-androstadien-3-one (12) yielded the two stereoisomeric spiro-lactones 13 and 14, which result from a di-n-methane photorearrangement. A third product, the oxa-anthrasteroid 15, was also isolated (Scheme 3).

2545 erhitzt. Nach dem Abkiihlen wurdc mit 800 ml Dichlorathan vcrdunnt, mit Wasser und wasseriger Natriumcarbonatlosung gewaschen, uber wasserfreiem Natriumcarbonat getrocknet, eingedampft und an Kicselgel chromatographisch gcreinigt . Dic durch Dichlorathan/Diathylather 3 : 2 eluierten blauen Fraktionen wurden eingedamyft und der Ruckstand durch Einengen einer Liisung in Dichlormethan/Ligroin umkristallisiert. Das Diinnschichtchrornatogramm zeigt neben einer blauen Hauptzone eine zweite blaue Zone geringcr Intensitat, Smp. 190-195' (Zcrs.). Ausbeute 0,199 g C24HzoN208 mit 20 Mol.-Yo He0 Bcr. C 74,28 H 5,30 0 13,19 C1 O , O U~o (388,04) Gef. ,, 73,97 ,, 5,63 ,, 13,17 ,, 0,23%

Bei der Photolyse in Benzol erweist das Titelsteroid (I) eine besond re Reaktivität an der C‐5‐Doppelbindung, wobei die Derivate (II) und (III) erhalten werden.