Methanol → 1-[5-(3-fluoropyridin-4-yl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine Fumarate

tert-Butyl{[5-(3-fluoropyridin-4-yl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]methyl}methylcarbamate (60 mg) was dissolved in methanol (5 mL), a 4 mol/L hydrogen chloride-ethyl acetate solution (1.5 mL) was added and the mixture was stirred at 70° C. for 30 min. The reaction mixture was concentrated under reduced pressure and a saturated aqueous sodium hydrogencarbonate solution was added. The mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was dissolved in ethyl acetate (8 mL), a solution of fumaric acid (58 mg) in methanol (2 mL) was added, and the obtained crystals were collected by filtration to give the title compound as colorless crystals (yield 45 mg, 72%).