“…The mixture was stirred at rt for 15 min and then refluxed for 4 h. The volatiles were evaporated under reduced pressure, and the resulting residue was poured by portion in cold aq. 1 M HCl to give a yellow precipitate that was filtered and washed with water to afford a mixture of 2-( 5 [3,2-b]quinoxaline-3-carboxamide (26). Following the procedure used to prepare 76, a solution of 93 and 94 (5.0 g, 11.8 mmol) in sulfuric acid (50 mL) was stirred for 1 h at rt to provide a mixture of 2-amino-8-bromo-1-(3methoxy-2,6-dimethylphenyl)pyrrolo [3,2-b]quinoxaline-3-carboxamide and 2-amino-5-bromo-1-(3-methoxy-2,6-dimethylphenyl)pyrrolo [2,3-b]quinoxaline-3-carboxamide (5.2 g, quantitative yield, ESI MS m/z 442.0 [M + H] + ) as a yellow solid.…”