PROCESS FOR THE PREPARATION OF 2-METHYLENE- QUINOXALINE-1,4-DIOXIDE DERIVATIVES

摘要

The invention relates to a process for the praparaion of 2-methylene-1,4-dioxide derivatives of the general formula /I/ wherein A represents a hydroxyl or an amino group, or a group of the general formula -NH-COOR1, wherein R1 denotes a C1-4 alkyl group; or a group of the general formula -NH-CX-NH2, wherein X stands for oxygen or sulfur; or a group of the formula -NH-C/=NH/-NH2; or a group of the general formula -NH-R2, wherein R2 represents C1-6 alkyl, ohenyl, benzyl, hydroxyl or hydroxy-/C2-4 alkyl/; or a group of the general formula -NH-CO-R3, wherein R3 stands for a C1-20 alkyl group, a phenyl group optionally substituted by one, tno or three identical or different substituent/s/ selected from the group consisting of hydroxyl, amino, nitro, C1-4 alkyl, C1-4 alkoxy or halogen; a piperidyl, a pyridyl, a furyl, a nitrofuryl, a pyrazinyl, a pyrimidyl, a naphthyl, a hydroxynaphthyl, a phenylalkyl, an 1,2,4-triazinyl, an .alpha.,.alpha. -diphenyl-.alpha.-hydroxymethyl, a cyanomethyl, a halomethyl or a hydroxymethyl group, characterized by dehydrating a compound of the general formula /II/ wherein A has the same meanings as above. The compounds of the general formula /I/ possessing bactericidal and weight-gain increasing properties can be obtained in a high purity with an excellent yield by the process according to the invention.