To a solution of N-[6-(3-amino-4-fluorophenoxy)imidazo[1,2-b]pyridazin-2-yl]cyclopropanecarboxamide (200 mg, 0.61 mmol) in N,N-dimethylacetamide (4.0 mL) was added 2,5-dimethyl-1,3-oxazole-4-carbonyl chloride (127 mg, 0.79 mmol), and the mixture was stirred at room temperature for 2 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate, washed with saturated brine, dried over anhydrous sodium sulfate, and filtrated. The solvent was evaporated under reduced pressure, and the residue was washed with ethanol to give the title compound (198 mg, 72%) as a white powder.
