0.12 g of 60% sodium hydride (oil-based) and 0.56 g of methyl iodide were added to a mixture of 0.78 g of 2-ethylsulfanyl-4-trifluoromethyl-N-(5-trifluoromethyl-pyri din-2-yl)-benzamide and 5 mL of THF, and the mixture was stirred at room temperature for 2 hours. 1 g of methyl iodide was added to the reaction mixture, and the mixture was stirred at room temperature for 2 hours. 1 g of methyl iodide was further added to the reaction mixture, and the mixture was stirred at room temperature for 1 hour. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate and then concentrated under reduced pressure, and the resulting residue was applied to a silica gel column chromatography to obtain 0.59 g of 2-ethylsulfanyl-N-methyl-4-trifluoromethyl-N-(5-trifluoromethyl-pyridin-2-yl)-benzamide (hereinafter, referred to as Compound of Present Invention 2).
