GB471908A - Process for the manufacture of trans-androsterone and its derivatives - Google Patents

Abstract

Dehydro-androsterone is converted into transandrosterone by the action of mild hydrogenating agents such as hydrogen in the presence of platinum black at room temperature or nacent hydrogen at a low temperature. Careful regulation of the reaction conditions particularly the temperature and pressure enables the hydrogenation of the nuclear double bond to take place without simultaneous reduction of the keto group. Instead of dehydro-androsterone itself, derivatives may be used, in which the hydroxyl group is replaced by an o-acyl group or an ether group such as o-alkyl or o-aryl. There is thus obtained corresponding derivatives of trans-androsterone. The dehydro-androsterone used for the process of this invention may be prepared as described in Specification 449,379. In examples: (1) Dehydroandrosterone is catalytically hydrogenated in glacial acetic acid solution in the presence of platinum black at room temperature. The hydrogenation is interrupted after 1 mol. of hydrogen has been absorbed, and the product poured into water and extracted with ether. The transandrosterone is recrystallized from alcohol; (2) Dehydroandrosterone acetate is hydrogenated under the conditions of example (1) to give trans-androsterone acetate. Specification 346,130, [Group VI], also is referred to. The Specification as open to inspection under Sect. 91 comprises also the hydrogenation of halogen derivatives of dehydroandrosterone to the corresponding halogen derivatives of trans-androsterone. This subject-matter does not appear in the Specification as accepted.