Syntheses of azasteroids

The cyclization of compounds (120) and (121) led to isomeric quaternary salts, which were isolated in the form of the perchlorates (124) and (125). Saturated derivatives were obtained by the reduction of the latter. In this process, the cis-C/D isomer (125) formed both possible epimers (129) and (130), while the trans-C/D isomer (124) formed only the 9/S derivative (128). The configurations of compounds (128)-(130) at C9 were not shown rigidly. The method of synthesis considered does not offer the possibility of the stereo-directive preparation of 8-azasteroids with the nat- 

When 1,5-decalindione (4) is boiled with phenylhydrazine in acetic acid, in addition to other products, 6-aza-B-nor-D-homoequilenin derivatives (136) and (137) are formed [183]. 

Syntheses from 5 - Methoxy - 2 Tetralone. These total syntheses, carried out mainly by Johnson and his colleagues, take place in three main stages [98]  

The intermediates in the production of (140) were isolated when the formation of ring A was carried out under mild conditions (without boiling with sodium methoxide) which led through the diketone (139) to the epim-eric ketols (141). Rings A and B of these compounds form a bicyclo-[3,3,1]-nonane system [57] originally, these products were assigned the structure of compounds (142) epimeric at C5 with the decalin system of rings A and B [56]. The ratio of the isomers of ketol (141) formed depends on the reaction conditions and, in the first place, on the concentra- 

The catalytic hydrogenation of the cis-A/B ketone (151) gave the cis-syn-c is-isomer (152). The Birch reduction of the ketone (151) via the corresponding ethylene ketal led after hydrolysis to a mixture of the cis-anti-trans-isomer (154) and the cis-syn-trans-isomer (155) in a ratio of 2 1. The stereodirected synthesis of the isomer (154) was effected from the 3q -hydroxy derivative (153) by Birch reduction with subsequent oxidation of the 3ce-hydroxy group. 

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Syntheses of Azasteroids, Qxasteroids, and Thia-steroids. The AB route has been used to effect the total syn-... 

Syntheses of Azasteroids. Syntheses of 6-, 8-, and 9-aza-steroids have been carried out by the method of building up the steroid skeleton considered in this section (Schemes 92 and 93). 

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