反应详情

To (2β,3α,5α)-21-chloro-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)pregnane-11,20-dione (3.1 g) was added a solution of methanesulfonic acid (615 mg) in methanol (63 ml) and then a solution of potassium thiocyanate (12.4 g) in water (32 ml). The resulting solution was stirred at room temperature for 24 h, poured into water and sodium carbonate was then added until the pH exceeded 9. The precipitated solid was filtered off, washed with water and dissolved in dichloromethane. This 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 diethyl ether and then from methanol to give (2β,3α,5α)-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)-21-thiocyanatopregnane-11,20-dione (572 mg). m.p. 197°-198° C.; [α]D +99.3° (c 0.8).

1. additionwas then added until the pH
2. filtrationThe precipitated solid was filtered off
3. washwashed with water
4. dissolutiondissolved in dichloromethane
5. dry with materialThis 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 diethyl ether