A suspension of 1-(3-{[2-(1H-1,2,4-triazol-3-ylthio)ethyl]oxy}phenyl)methanamine obtained in Reference Example 3 (318 mg, 1.27 mmol), ethyl 6-fluoro-4-oxo-3,4-dihydroquinazoline-2-carboxylate obtained in Reference Example 52 (100 mg, 0.423 mmol) and diisopropylethylamine (0.442 mL, 2.54 mmol) in THF (9 mL)-ethanol (3 mL) was stirred at 90° C. for 2 days. The reaction solvent was evaporated under reduced pressure, and the residue was extracted with 0.1N hydrochloric acid and THF-ethyl acetate. The organic layer was washed with saturated brine, dried over sodium sulfate, and concentrated. The residue was crystallized from toluene-ethanol, and the obtained crude crystals were recrystallized from THF-IPE to give the title compound as a white powder (45.7 mg, 25%).
