6-Methylsulfanyl-[2,2′]bipyridin-3-ol (6 mg), 4-chloro-6,7-dimethoxyquinoline (18 mg), 4-dimethylaminopyridine (10 mg), and cesium carbonate (27 mg) were suspended in N,N-dimethyl sulfoxide (1 ml), and the suspension was stirred at 140° C. overnight. The reaction solution was cooled to room temperature, water was then added to the reaction solution, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was then washed with water and saturated brine and was dried over anhydrous magnesium sulfate. The solvent was removed by distillation under the reduced pressure, and the residue was purified by thin layer chromatography using acetone-hexane to give the title compound (1 mg, yield 8%).
