5-Bromo-N-methylpyrazine-2-sulfonamide (147 mg, 0.58 mmol) synthesized in Example (128b) and 3-{5-[(5R)-5-(Hydroxylmethyl)-4,5-dihydro-1,3-oxazol-2-yl]-1H-pyrrol-2-yl}-5-[(1S)-2-methoxy-1-methylethoxy]phenol (262 mg, 0.76 mmol) synthesized in Example (125g) were dissolved in acetonitrile (6 mL), and potassium carbonate (161 mg, 1.17 mmol) was added, followed by stirring for 4 hours under nitrogen atmosphere. Water (20 mL) was added to the reaction solution, and extraction was carried out twice with ethyl acetate (20 mL). The organic layer was washed with saturated brine, and subsequently dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified using silica gel column chromatography (elution solvent: methanol/methylene chloride=0%-3.5%) to afford the desired compound (161 mg, yield 54%) as a white solid.
