Hydrochloric Acid → 2-{(3S,4R)-4-{[(4-Chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-[(1-ethylpropyl)amino]piperidin-1-yl}-1,3-benzothiazole-7-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A 2 N aqueous lithium hydroxide solution (439 μL, 0.877 mmol) was added to a mixed solution of ethyl 2-{(3S,4R)-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-[(1-ethylpropyl)amino]piperidin-1-yl}-1,3-benzothiazole-7-carboxylate obtained in Example (202f) (48.0 mg, 0.088 mmol) in methanol (0.3 mL) and tetrahydrofuran (0.3 mL) at room temperature, and the mixture was stirred at 70° C. for two hours. The reaction solution was concentrated under reduced pressure and water was added. The aqueous layer was washed with diethyl ether. A 1 N aqueous hydrochloric acid solution (877 μL, 0.877 mmol) was added to the aqueous layer, followed by extraction with ethyl acetate. The resulting organic layer was washed with water and brine, and dried over anhydrous sodium sulfate, and then the insoluble matter was separated by filtration. The filtrate was concentrated under reduced pressure to obtain 42 mg of the title compound (92%) as a pale yellow solid.

Provenance & Evidence