4-(5,6-Dimethyl-[2,2′]bipyridin-3-yloxy)-6-methoxy-quinolin-7-ol (compound 338) (80 mg) was dissolved in N,N-dimethylformamide (2 ml) to prepare a solution. Potassium carbonate (89 mg) and 2-bromoethanol (0.05 ml) were added to the solution, and the mixture was stirred at 70° C. overnight. The solvent was removed by distillation under the reduced pressure, water was then added to the residue, and the mixture was extracted with chloroform. The chloroform layer was washed with saturated brine and was dried over anhydrous sodium sulfate, the solvent was removed by distillation under the reduced pressure, and the residue was purified by thin layer chromatography using chloroform-methanol to give the title compound (77 mg, yield 88%).
