反应详情

To a 6 ml tetrahydrofuran suspension of 100 mg (0.283 mmol) of the compound obtained in Example 44, 48 μl (0.50 mmol) of ethyl chlorocarbonate and 98 μl (0.707 mmol) of triethylamine were added, and the mixture was stirred at room temperature for 3 hours. Further, 48 μl (0.50 mmol) of ethyl chlorocarbonate and 1 ml of pyridine were added, and the mixture was stirred at room temperature for 18 hours. Then, a 1M aqueous solution of sodium hydroxide was added to the reaction mixture, and the mixture was extracted with dichloromethane. The organic layer was washed with water and a saturated aqueous solution of sodium chloride. After the washed layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane=1/1˜2/1) to obtain 68 mg (57%) of the captioned compound.

1. additionwere added
2. stirringthe mixture was stirred at room temperature for 18 hours
3. extractionthe mixture was extracted with dichloromethane
4. washThe organic layer was washed with water
5. dry with materialAfter the washed layer was dried over anhydrous sodium sulfate
6. distillationthe solvent was distilled off under reduced pressure
7. customThe residue was purified by silica gel column chromatography (ethyl acetate/hexane=1/1˜2/1)