N1-Boc-N-(4-Methoxybenzyl)benzimidazol-5-amine (353 mg; 1 mmol; 1 eq.) was dissolved in DMF (5 ml), treated with K2CO3 (166 mg; 1.2 mmol; 1.2 eq.) and phenylpropylbromide (0.183 ml; 1.2 mmol; 1.2 eq.) and stirred at room temperature for 24 h. The mixture was diluted with water and extracted with ethyl acetate (3×25 ml). The combined organic layers were dried over Na2SO4 and evaporated. The remains were taken up with THF (5 ml), treated with 5 N NaOCH3 and stirred for 2 h at room temperature. The mixture was diluted with water and extracted with ethyl acetate (3×25 ml). The combined organic layers were dried over Na2SO4 and evaporated. The residue was purified by flash chromatography on silica using a CHCl3/MeOH gradient. Yield: 0.015 g (4.0%); MS m/z: 372.1 [M+H]+; 1H-NMR (500 MHz, DMSO d6): δ 1.84-1.90 (m, 2H); 2.62 (t, 2H, 3J=7.6 Hz); 3.39 (t, 2H, 3J=7.6 Hz); 3.39 (s, 3H); 4.45 (s, 2H); 6.71 (br s, 1H); 6.73 (dd, 1H, 4J=2.1 Hz, 3J=8.9 Hz); 6.83-6.85 (m, 2H); 7.12-7.14 (m, 2H); 7.16-7.19 (m, 3H); 7.24-7.27 (m, 2H); 7.36 (d, 1H, 3J=8.9 Hz); 8.08 (s, 1H); HPLC (METHOD [A]): rt 16.97 min (93.2%)
