反应详情

Sodium borohydride (64 mg) was added to a mixture of 170 mg of 17α-acetoxy-6β-chloro-1ξ,7α-dihydroxy-2-oxa-4-pregnene-3,20-dione, 62 mg of sodium hydrogen carbonate, 4 ml of tetrahydrofuran, 9.2 ml of methanol and 8.2 ml of water. The reaction mixture was stirred at room temperature for 30 minutes, and 4 ml of 50% hyrochloric acid was added. The mixture was extracted with ethyl acetate, and the extract was washed with a saturated aqueous solution of sodium hydrogen carbonate and dried over anhydrous magnesium sulfate. The solvent was evaporated, and the crude product was purified by TLC [developing solvent: chloroform/acetone (9/1)] to give 154 mg of 17α-acetoxy-6β-chloro-7α-hydroxy-2-oxa-4-pregnene-3,20-dione. The 1H NMR spectrum of this compound was the same as that of the compound produced in Example 18.

1. extractionThe mixture was extracted with ethyl acetate
2. washthe extract was washed with a saturated aqueous solution of sodium hydrogen carbonate
3. dry with materialdried over anhydrous magnesium sulfate
4. customThe solvent was evaporated
5. customthe crude product was purified by TLC [developing solvent: chloroform/acetone (9/1)]