摘要 |
<p>Process for the preparation of 1,4-dioxoquinoxalines (I) by reacting p-nitroso-N,N-dimethylaniline with 2-methyl-1,4-dioxoquinoxaline to give intermediate (III) which is reacted with the carbazate H2N-NHCOOR1 (II) (where R1 is methyl, ethyl, proply, isopropyl or opt. substd aryl). (I) are bactericides used as medicaments for humans and animals. They may be added to animal feeds as growth promoters. In an example, (I) (R1 is methyl) is prepd in 85% yield by reacting 1,4-dioxo-quinoxaline-2-methylene-p-phenylimino-dimethylaniline in isopropanol with methyl carbazate, acidifying and refluxing.</p> |