Abstract
In connection with our studies to develop an assay method for 4-chloro-2-(o-chlorobenzoyl)-N-methyl-Nα-glycylglycinanilide (1), a colored substance formed by the reaction of 1 with the reagent 3, 5-dibromosalicylaldehyde (DBSA) was isolated and its chemical structure was investigated. Another colored substance formed by the same reaction of glycinemonomethylamide (3) with DBSA was also isolated, and the chromophoric structure was shown to be essentially the same as that of the compound formed in the reaction of 1 with DBSA. On the basis of spectrometric and chemical evidence, the colored compounds were determined to be N-substituted 5-(3, 5-dibromo-2-hydroxybenzylidene)-2-(3, 5-dibromo-2-hydroxyphenyl)-1-imidazoline-4-ones. The reaction mechanism of the coloration in the assay of 1 is discussed.
