反应详情

To a cold solution of 2-{(2S,3S)-2-[(R)-2-(4-acetylamino-phenyl)-2-tert-butoxycarbonylamino-acetylamino]-3-phenyl-butyryl-amino}-thiazole-4-carboxylic acid methyl ester (107 mg, 0.175 mmol) in dichloromethane (6 mL), was added trifluoroacetic acid (4 mL). The reaction mixture was stirred at room temperature for 45 minutes, followed by removal of volatiles in vacuo. To the residue was added diethyl ether (10 mL) and the resulting suspension was separated by centrifugation. The solid was dissolved in ethyl acetate and washed with saturated aqueous sodium bicarbonate. The aqueous layer was extracted with ethyl acetate (2×50 mL). The combined organic layers were dried over sodium sulfate, filtered and concentrated to give crude 2-{(2S,3S)-2-[(R)-2-(4-acetylamino-phenyl)-2-amino-acetylamino]-3-phenyl-butyrylamino}-thiazole-4-carboxylic acid methyl ester which was used immediately in the following step of the synthesis.

1. customfollowed by removal of volatiles in vacuo
2. additionTo the residue was added diethyl ether (10 mL)
3. customthe resulting suspension was separated by centrifugation
4. dissolutionThe solid was dissolved in ethyl acetate
5. washwashed with saturated aqueous sodium bicarbonate
6. extractionThe aqueous layer was extracted with ethyl acetate (2×50 mL)
7. dry with materialThe combined organic layers were dried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated