Ethyl (R)-2-methanesulfonyl-4-(3-methyl-1,1-dioxo-1λ6-isothiazolidin-2-yl)benzoate (361 mg) described in Preparation Example 28 was dissolved in ethanol (5 mL), 1N aqueous sodium hydroxide solution (1.5 mL) was added, and the mixture was stirred at 60° C. After completion of the reaction, the reaction mixture was neutralized with 1N hydrochloric acid (1.5 mL), 1-(5-cyclopropyl-3-methylpyridin-2-yl)piperazine hydrochloride (254 mg) described in Preparation Example 82, N-methylmorpholine (0.2 mL) and 4-(4,6-dimethoxy[1.3.5]triazin-2-yl)-4-methylmorpholinium chloride hydrate (277 mg) were added, and the mixture was stirred at room temperature overnight. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and the solvent was evaporated. The obtained residue was purified by silica gel column chromatography (ethyl acetate:hexane) to give the title compound (292 mg).
