Triethylamine (0.185 g) and benzenesulfonyl chloride (0.210 g) are added to a chloroform (10 ml) solution of 1-(4-aminobenzyl)-2-methyl-6-[(2-pyridylmethyl) carbamoyl]benzimidazole (0.340 g), and the solution is stirred for eight hours at room temperature. Water is added and the reaction is halted. A chloroform extraction is performed. An organic layer is washed with water (three times), and dried. After concentration, the residue is purified through silica gel column chromatography (eluate: ethyl acetate/methanol=100/0˜4/1), and thus, 1-[4-(benzenesulfonylamino)benzyl]-2-methyl-6-[(2-pyridylmethyl)carbamoyl]benzimidazole (263) (0.300 g) is obtained. 1H-NMR (CDCl3, δ): 2.53 (3H, s), 4.78 (2H, d, J=4.8 Hz), 5.28 (2H, s), 6.90 (2H, t, J=8.6 Hz), 6.99 (2H, d, J=8.5 Hz), 7.11 (1H, s), 7.23 (1H, dd, J=5.5 and 7.2 Hz), 7.34 (1H, d, J=7.7 Hz), 7.40 (2H, t, J=8.1 Hz), 7.50 (1H, t, J=7.5 Hz), 7.66-7.74 (6H, m), 7.92 (1H, s), 8.56 (1H, d, J=4.8 Hz).
