Partial reduction of quinoxaline 1,4-dioxide derivatives with L-ascorbic acid

Abstract

Partial reduction of quinoxaline 1,4-dioxide derivatives with L-ascorbic acid has been elaborated. Quinoxaline 1,4-dioxide, 2,3-dimethylquinoxaline 1,4-dioxide, 2-methylquinoxaline 1,4-dioxide and 2-(N-(2-hydroxyethyl)carbamoyl)-3-methylquinoxaline 1,4-dioxide afforded monoxides. In the monomethyl derivatives the more distant N-O bond is reduced. In addition to the monoxide, quinoxaline 1,4-dioxide afforded small amount of quinoxaline. Structures of all the compounds have been confirmed by 1H and 13C NMR spectroscopy.