HCID 19990456, compound → HCID 19990431, compound

Participants

Reaction Steps

A suspension of 7-ethoxalylaminosulfonyl-1-hydroxy-6-trifluoromethylquinoxaline-2,3(1H,4H)-dione (12.0 g, 28 mmol) in 150 ml of 1M hydrochloric acid was heated at reflux for 2 h with stirring. The cooled mixture was filtered and the isolated solid was washed with water and light petroleum. The crude product was recrystallized from water with decolourizing charcoal and dried in vacuo over phosphorous pentoxide for 3 h to give 7.1 g (77%) of the pure title compound. M.p. 296° C. decomp. (DSC); IR (KBr): 1700, 1615 cm-1 ; 1H-NMR (DMSO-d6): 7.67 (s, 1H, ArH), 7.77 (s, 2H, NH2), 8.26 (s, 1H, ArH), 12.2 (broad s, 2H, NH and OH); MS m/e: 325 (M+, 100%).

Provenance & Evidence