Reaction Steps
A solution of 1,1′-carbonyldiimidazole (80.1 mg, 0.494 mmol), 2-amino-1-methylbenzimidazole (70.8 mg, 0.481 mmol), and DIPEA (0.17 mL, 0.97 mmol) in DMF (5 mL) was stirred at room temperature for 2.5 h. To this solution was added DIPEA (0.17 mL, 0.97 mmol) and COMPOUND 249 (149 mg, 0.479 mmol), and the resultant solution was stirred at 60° C. overnight. The solution was concentrated to dryness, treated with saturated aqueous NaHCO3 (30 mL), and extracted with CH2Cl2 (3×15 mL). The combined organic extracts were dried (Na2SO4), filtered, and concentrated. Purification of the crude material by flash chromatography on silica gel (CH2Cl2/MeOH/NH4OH, 92:4:4) provided COMPOUND 290 (62 mg, 27%) as a white solid. 1H NMR (CDCl3) δ 1.63-1.76 (m, 2H), 1.80-2.05 (m, 2H), 2.10 (s, 6H), 2.43-2.80 (m, 3H), 3.54 (s, 3H), 3.83 (s, 4H), 4.61 (br s, 1H), 4.90 (br s, 1H), 7.04-7.20 (m, 6H), 7.36 (d, 2H, J=7.2 Hz), 8.35 (d, 2H, J=1.2 Hz); 13C NMR (CDCl3) 18.43, 27.22, 28.22, 42.96, 45.27, 55.07, 58.34, 108.42, 110.29, 122.33, 122.36, 122.72, 129.12, 131.10, 133.84, 138.37, 146.25, 154.51, 157.80, 163.72; ES-MS m/z 506 (M+Na). Anal. Calcd. for C28H33N7O.0.9H2O: C, 67.28; H, 7.02; N, 19.62. Found: C, 67.19; H, 6.97; N, 19.50.
