GB881501A - Substituted pregnenes - Google Patents

Abstract

The invention comprises D 4-pregnenes having the general formula <FORM:0881501/IV (b)/1> in which R is a hydrogen atom or a lower alkanoyl radical having 1-6 carbon atoms, X is a halogen atom and X1 is the divalent radical -CO- or -CHOH-, and a process for the preparation thereof which comprises (a) treating a D 4,9(11)-steroid of the general formula <FORM:0881501/IV (b)/2> in which R is a hydrogen atom or a lower alkanoyl alkanoyl group and R1 is hydrogen, or the 16 and 17 position is bonded together to form the 16a ,17a -methylenedioxy steroid, and -Y-Z-is the following <FORM:0881501/IV (b)/3> to form the 9a -halo-11b -hydroxy derivative, and then doing the following in any desired sequence (b) if desired, when R and R1 are bonded together to form the 16a ,17a -methylenedioxy or where R is a lower-alkanoyl group, oxidising to convert the 11b -hydroxy group to an 11-keto group (c) when the 16,17 positions form a <FORM:0881501/IV (b)/4> group, hydrolysing the product produced in step (a) or step (b) to convert to a product in which R and R1 form a hydrogen atom, (d) and further, if desired, when R is hydrogen, alkanoylating to form the 16a -lower-alkanoyl steroid of formula I. Conversion to the 9a -halo-11b -hydroxy steroid in step (a) may be effected with N-bromosuccinimide or 1,3-dichloro-5,5-dimethylhydantoin in the presence of a solvent and then with perchloric acid when -Y-Z- represents <FORM:0881501/IV (b)/5> or with hydrohalic acid when -Y-Z- is <FORM:0881501/IV (b)/6> Illustrative products of the invention are 16a -acetoxy - 9a - bromo - 11b ,17a - dihydroxy - 4 - pregnene - 3,20 - dione, 16a - acetoxy - 9a - chloro - 11b ,17a - dihydroxy - 4 - pregnene - 3,20 - dione, 9a - fluoro - 11b ,16a ,17a - trihydroxy - 4 - pregnene - 3,20 - dione, 16a - acetoxy - 9a - fluoro-11b ,17a - dihydroxy - 4 - pregnene - 3,20 - dione and 9a - bromo - 11b ,16a ,17a - trihydroxy - 4 - pregnene-3,20-dione.