6-Bromo-4 (3H) qulnazdnone (I). It was prepared by direct bromination of 4 (3H) quinazolinone. 4 (3H)-Quinazolinone (1.46 g, 0.01 mol) was stirred overnight in 30 mL of water containing bromine (1.6 g, 0.01 mol) and KBr (1.19 g, 0.01 mol). The resulting orange white slurry was warmed until the orange color due to bromine disappeared. The reaction mixture was then cooled, filtered, washed with a little acetone, and dried in air. ...