The preparation of 2, 4-dimethyl-7, 9-dihydroxy-3-phenoxazone, 2, 4-dimethyJ-7-hydroxy-3- phenoxazone-9-carboxylic acid, and 9-hydroxy-5-benzo [a] phenoxazone-11-carboxylic acid by the reaction of corresponding nitrosophenols with phloroglucinol or 3, 5- dihydroxybenzoic acid in ethylene glycol solutions is described. The tautomerism in the prepared compounds is discussed on the basis of their acetylation and IR and PMR ...
