The invention comprises D 4-pregnene-6b , 20-diol-3-one and the 20-acylates thereof, allopregnan-20b -ol-3, 6-dione and the 20-acylates thereof, and D 4-pregnene-3b , 6, 20b -triol triacylates; a process for the preparation of D 4-pregnene-6b , 20b -diol-3-one or of its isomer allopregnan-20b -ol-3:6-dione or of 20-acylates thereof by selectively oxidizing the 3-hydroxy group of D 4-pregnene-3b , 6b , 20b -triol with manganese dioxide in an inert solvent and, if desired, separating the resulting oxidation products by recrystallization into the desired individual components whereupon, if desired, acylating the separated components to form the 20-acylate derivatives; and a process for the preparation of allopregnan-20b -ol-3:6-dione by isolating part of the D 4-pregnene-6b , 20b -diol-3-one from the reaction mixture of the previous process and then heating the remaining mixture with alkali or acid-preferably with an alcoholic alkali metal hydroxide solution, or by heating D 4-pregnene-6b , 20b -diol-3-one itself with alkali or acid. D 4-Pregnene-3b , 6b , 20b -triol and the above triacylates thereof, are prepared by reducing the corresponding 20-one with lithium aluminium hydride or sodium borohydride and, when required, acylating to form the triacylates.
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