Patent GB-1000890-A (GB)
Title: Improvements in or relating to compounds of the androstane series
IPC: C07J1/00
Filed: 1964-06-18
Abstract: The invention comprises compounds of the general formula: <FORM:1000890/C2/1> wherein X and Z are each a carbonyl, b -hydroxymethylene, or b -alkanoyloxy-methylene radical and the alkanoyl groupings of X and Z each contain from 2-6 carbon atoms inclusive, and processes for the preparation thereof by contacting 5a - acetoxy - 6b ,19 - epoxyandrostene-3,17-dione with a mixture of zinc and zinc chioride.  5 - Acetoxy - 6b ,19 - epoxy androstene-3,17-kione may be obtained (a) by contacting a compound of the general formula <FORM:1000890/C2/2> wherein X1 is a carbonyl or b -alkanoyloxymethylene radical, and the 3b -alkanoyloxy radical and optional 17b -alkanoyloxy grouping each contain from 2-6 carbon atoms inclusive, with acetic acid in the presence of an acid catalyst, contacting the resulting 17-oxygenated 5a  - acetoxyandrostane - 3b ,6b  - diol 3-alkanoate with a heavy metal acetate, preferably lead tetracetate, to afford the corresponding 17 - oxygenated 5a  - acetoxy - 6b ,19 - epoxyandrostan -3b -ol 3-alkanoate; selectively hydrolysing the latter substance with an acidic or alkaline reagent; and contacting the resulting 17 - oxygenated 5a  - acetoxy - 6b ,19 - epoxy androstan - 3b  - ol with a chromium oxidizing agent in which the chromium exists in the +6 oxidation state, e.g. chromic acid, to afford the desired 5a  - acetoxy - 6b ,19 - epoxyandrostane-3, 17-dione; (b) by selectively hydrolysing a compound of the formula <FORM:1000890/C2/3> wherein X1 is a carbonyl or b -acetoxymethylene radical, by contacting that compound with an alkaline reagent in an anhydrous organic solvent medium; selectively acylating the resulting 17 - oxygenated 5a  - acetoxyandrostane-3b ,6b -diol with an acetylating agent, contacting the resulting 17-oxygenated androstane 3b ,5a ,6b -triol 3,5-diacetate with a heavy metal acetate preferably lead tetracetate, to afford the corresponding 17-oxygenated 6b ,19-epoxyandrostane - 3b ,5a  - diol 3,5 - diacetate; selectively hydrolysing the latter substance with an acidic or alkaline reagent; and contacting the resulting 17-oxygenated 5a -acetoxy-6b , 19 - epoxyandrostan - 3b  - ol with a chromium oxidizing agent in which the chromium exists in the +6 oxidation state, e.g. chromic acid, to afford the desired 5a -acetoxy-6b ,19-epoxyandrostane-3, 17 -dione; and (c) by contacting a compound of the formula <FORM:1000890/C2/4> wherein X1 is a carbonyl or b -alkanoyloxymethylene radical, and the 3b -alkanoyloxy radical and the optional 17b -alkanoyloxy grouping each contains from 2-6 carbon atoms, with a mixture of a heavy metal acetate, preferably lead tetracetate, and acetic acid to afford the corresponding 17-oxygenated 5a -acetoxy - 6b ,19 - epoxyandrostan - 3b  - ol 3 alkanoate; selectively hydrolysing the latter substance with an acidic or alkaline reagent; and contacting the resulting 17-oxygenated 5-acetoxy 6b ,19-epoxyandrostan-3b -ol with a chromium oxidizing agent in which the chromium exists in the +6 oxidation state, e.g. chromic acid, to afford the desired 5a -acetoxy-6b ,19-epoxyandrostane-3,17-dione.