Quinoxaline 1, 4-dioxide (XIIIa) with acetic anhydride gave 1-acetoxy-2 (1H)-quinoxalinone (XIVa) which was prone to facile hydrolysis to yield 1-hydroxy-2 (1H)-quinoxalinone (XVa). Both XIVa and XVa were isolated from the reaction mixture. On prolonged heating with acetic anhydride, XIIIa, XIVa, and XVa were converted slowly to the same end product, 2, 3 (1H, 4H)-quinoxalinedione (XXa). 6-Ethoxy-(XIIIb), 6-methoxy-(XIIIc), and 6- ...