反应详情

To a mixture of (2β,3α,5α)-21-chloro-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)pregnan-20-one methanesulfonate (1:1) salt (1.5 g) in methanol (63 ml) was added a solution of potassium thiocyanate (5.14 g) in water (32 ml). The resulting solution was stirred at room temperature for 72 h, then poured into water and sodium carbonate was added until the pH exceeded 9. The precipitated solid was filtered off, washed with water and dissolved in dichloromethane. The solution was dried over sodium sulfate and the solvent was removed under reduced pressure. The residue was chromatographed on silica gel and the purified product was crystallised from methanol and then from diethyl ether to give (2β,3α,5α)-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)-21-thiocyanatopregnan-20-one (497 mg). m.p. 165.5°-166.5° C.; [α]D +121.1° (c 1.3).

1. additionwas added until the pH
2. filtrationThe precipitated solid was filtered off
3. washwashed with water
4. dissolutiondissolved in dichloromethane
5. dry with materialThe solution was dried over sodium sulfate
6. customthe solvent was removed under reduced pressure
7. customThe residue was chromatographed on silica gel
8. customthe purified product was crystallised from methanol