To a suspension of sodium hydride (60% in oil, 34 mg) in tetrahydrofuran (2 mL) were added tert-butyl {[4-fluoro-5-(2-fluoropyridin-3-yl)-1H-pyrrol-3-yl]methyl}methylcarbamate (226 mg), 15-crown-5 (185 mg) and a solution of 2-methylpyridine-3-sulfonyl chloride (174 mg) in tetrahydrofuran (1 mL) at room temperature, and the mixture was stirred for 18 hr. The reaction mixture was diluted with water and extracted with ethyl acetate. The separated aqueous layer was extracted again with ethyl acetate. Combined organic layers were washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=17:3→1:1) to give the title compound as a yellow oil (yield 288 mg, 86%).
