喹喔啉1，4-二氧化物的合成及抗菌活性

Synthesis and Antibacterial Activity of Quinoxalines 1,4-di-N-Oxide

邻硝基苯胺氧化闭环得到的苯并呋咱一氧化物,与β-二酮或β-酮酯直接进行Beirut反应缩合得到喹喔啉1,4-二氧化物1a～1c,分别进行羟醛缩合以及酯交换反应得到3或4。体外抗菌试验表明,1b与3的活性明显优于痢菌净,1c与4的活性与痢菌净相当。

Benzofurazan N-oxide was prepared from o-nitroaniline by oxidization and cyclization, and treated by Beirut reaction with β-diketone and β-ketoester to give quinoxalines 1,4-di-N-oxide （1a-1c）. Compounds 3 and 4 were obtained by aldol condensation or ester exchange, respectively. The results of the in vitro antibacterial test showed that the compound 1b and 3 had better activities than mequindox （1a）, 1c and 4 had the effect comparable to that of 1a.