To a solution of 3-{[(3-{[2-chloro-5-(methyloxy)phenyl]amino}quinoxalin-2-yl)amino]sulfonyl}benzoic acid (0.20 g, 0.42 mmol) in dimethylformamide (4 mL) were added 2-(7-Aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HATU, 0.32 g, 0.83 mmol) and N-ethyldiisopropylamine (DIEA, 0.13 g, 1.04 mmol) at room temperature. The reaction was stirred for 15 min before N,N-dimethylethane-1,2-diamine (73 mg, 0.83 mmol) was added. The reaction mixture was allowed to stir overnight. The reaction was diluted with ethyl acetate (200 mL) and washed with water (50 mL), saturated aqueous sodium bicarbonate (40 mL), 1.0 N aqueous hydrochloric acid (30 mL), and saturated aqueous sodium chloride (25 mL). The organic layer was dried over magnesium sulfate, filtered and concentrated at reduced pressure to afford 3-{[(3-{[2-chloro-5-(methyloxy)phenyl]amino}quinoxalin-2-yl)amino]sulfonyl}-N-[2-(dimethylamino)ethyl]benzamide (0.20 g, 87%) as yellow solid. MS (EI) for C26H27ClN6O4S: 555.1 (MH+).
