5-amino-4-(3-aminobenzoyl)-1-(4-fluorophenyl)pyrazole (0.5 g, 1.6 mmol), 1-bromo-3-chloropropane (0.26 g, 1.6 mmol) and cesium carbonate (0.52 g, 1.6 mmol) in dimethylformamide (25 ml) was heated at 80° C. After 2 days, the reaction mixture was cooled to room temperature and diluted with ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography (elution gradient: 20% acetone/hexanes) to give 5-amino-4-[3-(3-chloropropylamino)benzoyl]-1-(4-fluorophenyl)pyrazole (0.2 g) as a solid.
