反应详情

A 4 N hydrochloric acid/ethyl acetate solution (0.96 mL, 3.82 mmol) was added to a solution of ethyl 2-{3-[(tert-butoxycarbonyl)amino]azetidin-1-yl}-4-methyl-1,3-thiazole-5-carboxylate obtained in Example (218a) (261 mg, 0.76 mmol) in 1,4-dioxane (8 mL) at 0° C., and the mixture was stirred at room temperature for 7.5 hours. Then, a 4 N hydrochloric acid/ethyl acetate solution (0.96 mL, 3.82 mmol) was added, and the mixture was further stirred for 45 hours. The reaction solution was concentrated, and saturated aqueous sodium bicarbonate solution was added to the resulting residue. Thereafter, the mixture was extracted with ethyl acetate, and the combined organic layers were dried over anhydrous magnesium sulfate. Following filtration, the solvent was evaporated under reduced pressure to obtain 146 mg of the title compound as a pale yellow oily substance (79%).

1. stirringthe mixture was further stirred for 45 hours
2. concentrationThe reaction solution was concentrated
3. additionsaturated aqueous sodium bicarbonate solution was added to the resulting residue
4. extractionThereafter, the mixture was extracted with ethyl acetate
5. dry with materialthe combined organic layers were dried over anhydrous magnesium sulfate
6. filtrationfiltration
7. customthe solvent was evaporated under reduced pressure