A solution of Intermediate 3 (4.2 g) in dimethoxyethane (50 ml) was added with 1-methyl-1H-indazol-5-ylboronic acid (rgt1, 4.3 g), potassium carbonate (4.5 g), water (50 ml), and tetrakistriphenylphosphinepalladium(0) [henceforth abbreviated as Pd(PPh3)4] (2.7 g, Nacarai), and stirred at 90° C. for 14 hours. This reaction mixture was added with 2 N aqueous sodium hydroxide (5 ml), and further stirred at 80° C. for 0.5 hour. The reaction mixture was added with 1 N aqueous hydrochloric acid (10 ml), and extracted with diethyl ether (30 ml×2), and then the aqueous layer was neutralized with 5 N aqueous hydrochloric acid, and extracted with ethyl acetate. The reaction mixture was washed with saturated aqueous sodium hydrogencarbonate, the organic layer was dried, and then the solvent was evaporated under reduced pressure to obtain the title compound (3.3 g).
