PS-Carbodiimide resin (1.3 g) and 1-hydroxy benzotriazole (HOBt) (230 mg) were added to acetonitrile and THF solution (4 ml+6 ml) of 1-methyl-6-{3-[(2-methylaminoethyl)pyridin-4-ylmethylamino]propoxy}-1H-quinolin-2-one (304 mg) and 2,3-dihydrobenzofuran-7-carboxylic acid (164 mg). The mixture was stirred at room temperature overnight. After the reaction mixture was filtrated and condensed under reduced pressure, the residue was purified by silica gel column chromatography (ethyl acetate:methanol=1:0→10:1). The purified product was condensed under reduced pressure. A 4N-hydrogen chloride ethyl acetate solution (0.35 ml) was added to an ethyl acetate solution of the residue. The precipitated insoluble matter was separated, washed with ethyl acetate, and dried to give the title compound (324.2 mg) as a white powder.
