40 mg of 2-[6-fluoro-3-(4-fluorobenzyl)-3,4-dihydroisoquinolin-2(1H)-yl]ethanamine obtained in Example 180-b), 17 mg of 2-chloropyridine, and 36 mg of potassium carbonate were dissolved in 0.4 mL of DMF, followed by stirring at 120° C. overnight. After completion of the reaction, the reaction liquid was left to be cooled, and water was added thereto, followed by extraction with chloroform. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate and then concentrated under reduced pressure. The residue obtained was purified using silica gel chromatography (chloroform:ammonia saturated methanol=10:1) to obtain 6 mg (yield 13%) of a title compound as a light yellow oily substance.
