To 4-(5-(2-amino-pyridin-3-yl)-isoxazol-3-ylmethyl)-phenol (30 mg, 0.11 mmol) described in Manufacturing Example 5-1-1 were tetrahydrofuran (3 mL) and a 5N sodium hydroxide aqueous solution (22.4 μL, 0.11 mmol), which was dissolved by irradiating ultrasonic wave for 1 minute. The reaction solution was then concentrated under a reduced pressure, which gave a white solid. To a suspension of this solid in N,N-dimethylformamide (1 mL) was added an N,N-dimethylformamide (1 mL) solution of 3-methoxybenzyl chloride (21.0 mg, 0.13 mmol), which was stirred for 12 hours at 60° C. This mixture was cooled to room temperature and partitioned into water and ethyl acetate. The organic layer was separated, washed with water and saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under a reduced pressure, and this residue was purified by NH silica gel column chromatography (heptane: ethyl acetate=1:1) to obtain the title compound (35.1 mg, 81%).
