A mixture of (25R)-16-oxo-26-phthalimidocholesterol (5) (0.70 g, 1.32 mmoles), hydrazine monohydrate (5 ml, 102.8 mmoles), potassium hydroxide (2.85 g, 50.8 mmoles) and triethylene glycol (20 ml) was heated to 150° C. for 30 minutes, then heated to 200° C. over 2 hours during which time water vapor distilled out of the mixture. The reaction mixture was maintained at this temperature for about 16 hours, under nitrogen, until the reaction was complete as determined by thin layer chromatography. Thereafter, the reaction mixture was cooled, poured into water, and extracted with chloroform. The extract was washed with water, dried over sodium sulfate, and evaporated under reduced pressure. Chromatography of the residue on silica gel eluted with CHCl3 gave 0.34 g (66%) of (25R)-26-aminocholesterol. The product was recrystallized from methylene chloride-ether and was found to have a melting point of 150°-152° C.
