Next, 2-bromoacetic acid N-[2-(1-adamantyl)ethyl]-N-pentylamide (1.3 g, 3.5 mmol) was dissolved in anhydrous N,N-dimethylformamide (30 ml), potassium carbonate (1.5 g, 11 mmol), methyl iodide (1.6 g, 11 mmol) and 4-(2-aminoethyl)pyridine (0.43 g, 3.5 mmol) were added to the solution, and the mixture was stirred at an external temperature of 75° C. overnight. Water (100 ml) and diethyl ether (100 ml) were added to the reaction mixture to distribute it. The diethyl ether layer was washed with water (70 ml) twice and a saturated aqueous sodium chloride solution (120 ml) once successively, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. Then the obtained concentrate was purified by silica gel column chromatography to give the target compound (0.6 g, 40%) as an oily matter.
