General procedure for the synthesis of 2-quinoxalinecarboxamide from methyl quinoxaline-2-carboxylate: freshly prepared saturated ammonia (20 mL) was mixed with methyl quinoxaline-2-carboxylate (115 mg, 0.612 mmol) and the reaction was stirred for 18 h at room temperature. After completion of the reaction, the solvent was removed by evaporation under reduced pressure to give an off-white solid product in quantitative yield. Elemental analysis results (C9H7N3O, molecular weight 173.06): calculated values C 62.40%, H 4.07%, N 24.26%; measured values C 62.40%, H 4.11%, N 23.94%. 1H NMR (400 MHz, d6-DMSO) data: δ 9.439 (s, 1H, H5), 8.237 (dd, J1- 2 = 8 Hz, J1-3 = 2 Hz, 1H, H1), 8.194 (dd, J4-3 = 8 Hz, J4-2 = 0.8 Hz, 1H, H4), 7.997 (q-br, J2/3-3/2/1/4 = 10 Hz, 2H, H2/3).
