To a solution of 2-amino-9H-pyrido[2,3-b]indole-3-carboxamide (5, 70 mg, 0.310 mmol) in DMF (2 mL) was added potassium tert-butoxide (84 mg, 0.749 mmol). The reaction mixture was stirred at room temperature for 10 min, then 1-(2-bromoethyl)-1H-pyrrole (162 mg, 0.930 mmol) and potassium iodide (164 mg, 0.930 mmol) were added and the mixture was stirred at room temperature overnight. The reaction was quenched with water (50 mL) and extracted with ethyl acetate (150 mL). The layers were separated and the organic layer washed with brine (100 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. The crude product was purified by silica gel chromatography (0-3% methanol in methylene chloride gradient) to yield material which was subsequently triturated with ether to give pure 2-amino-9-[2-(1H-pyrrol-1-yl)ethyl]-9H-pyrido[2,3-b]indole-3-carboxamide as a white powder (20, 25 mg, 25%). NH4OAc standard conditions. DAD Retention time =6.79 min. M+H=320. 1H NMR (300 MHz, DMSO-d6): Δ 8.71 (s, 1H), 7.97-7.89 (m, 1H), 7.79-7.69 (m, 1H), 7.67-7.50 (m, 2H), 7.24-7.04 (m, 4H), 6.62-6.59 (m, 2H), 5.88-5.82 (m, 2H), 4.57-4.47 (m, 2H), 4.34-4.24 (m, 2H).
