GB829679A - Steroids - Google Patents

Abstract

The invention comprises cyclopentanophenanthrene compounds of the general formula <FORM:0829679/IV (b)/1> wherein R represents an acyl radical, and the 3-semicarbazones thereof, and the preparation thereof by reacting a 3,20-diketo-11b ,17a -dihydroxy - 21 - acyloxy - allopregnene such as the 21-acetoxy-, 21-propionoxy-, 21-heptanoyloxy or 21-benzoyloxy compound, with a halogenating agent that does not give halogen exclusively in the form of negative ions such as bromine, chlorine, N-bromo-amides, N-chloroamides and t-butyl-hypochlorite, to form a 2 - halo - 3,20 - diketo - 11b ,17a - dihydroxy - 21 - acyloxy-allopregnene and dehydrohalogenating the 2-halo compound. The 21-acyloxy radical may be a benzoyloxy radical or an alkanoyloxy radical such as the acetoxy radical. The dehydrohalogenating agent may be a tertiary amine such as pyridine or collidine. The dehydrohalogenation of the 2-halo compound may also be carried out by reaction with semicarbazide to form the 3-semicarbazones of the compounds of the above general formula which are then treated with pyruvic acid to form the desired 3-keto compounds. The compounds of the above general formula may be treated with methanolic potassium bicarbonate to form D 1 - 3,20 - triketo - 11b ,17a ,21 - trithydroxy - pregnene and may then be 21-esterified by treatment with an acylating agent-preferably a lower alkanoic anhydride such as acetic, propionic and heptanoic anhydride, benzoic anhydride, an alicyclic anhydride such as cyclopentylpropionic anhydride, an aliphatic dicarboxylic acid anhydride such as succinic, glutaric, b ,b -dimethylglutaric, maleic and adipic anhydride, and an aromatic dicarboxylic acid anhydride such as phthalic anhydride. Thus the 21-acetoxy, propionoxy, butyroxy, heptanoyloxy, benzoyloxy, hemisuccinate, hemi-b ,b - dimethylglutarate and cyclopentylpropionate of D 1 - 3,20 - diketo - 11b ,17a ,21 - trihydroxy-allopregnene may be prepared by the above esterification method. The product of the halogenation step may be 21-acetoxy-, 21-propionoxy- or 21-benzoyloxy-2-bromo-3,20-diketo-11b , 17a -dihydroxy-allopregnane. In the examples, D 1-3,20-diketo-11b ,17a -dihydroxy-21 - acetoxy - allopregnene 3 - semicarbazone, and D 1 - 3,20 - diketo - 11b ,17a ,21 - trihydroxy-allopregnene and the 21-acetate thereof are prepared. Specification 829,680 is referred to.