Dimethylformamide → 1-tert-butyl-N-[3-({7-cyano-2-[(cyclopropylcarbonyl)amino]-1,3-benzothiazol-6-yl}oxy)phenyl]-5-cyclopropyl-1H-pyrazole-4-carboxamide

Participants

Reaction Steps

To a solution of 1-tert-butyl-5-cyclopropyl-1H-pyrazole-4-carboxylic acid (71 mg, 0.342 mmol) in tetrahydrofuran (2 mL) were added oxalyl chloride (36 μL, 0.420 mmol) and N,N-dimethylformamide (20 μL), and the mixture was stirred at room temperature for 1 hr. The reaction mixture was concentrated under reduced pressure, and the residue was dissolved in N,N-dimethylacetamide (2 mL). N-[6-(3-Aminophenoxy)-7-cyano-1,3-benzothiazol-2-yl]cyclopropanecarboxamide (100 mg, 0.29 mmol) produced in Example 3(vi) was added to the solution, and the mixture was stirred at room temperature for 12 hr. The reaction mixture was diluted with ethyl acetate (15 mL), washed successively with 5% aqueous sodium hydrogen carbonate solution (7 mL) and saturated brine (7 mL), and dried over anhydrous sodium sulfate. Insoluble material was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (ethyl acetate/n-hexane=50/50→100/0), and the obtained solution was concentrated under reduced pressure. The residue was recrystallized from ethyl acetate/n-hexane to give the title compound (111 mg, 72%) as a white powder.

Provenance & Evidence