Synthesis and Biological Activity of Quinoid Compounds

The salts of quinone oximes were obtained in the reaction 4-(hydroxyimino)cyclohexa-2,5-dien-1-one, N,N'-cyclohexa-2,5-diene-1,4-diylidenedihydroxylamine and 1-(hydroxyimino)naphtalen-2(1H)-one with alkali metal hydroxides. The antimicrobial activity of these compounds was studied on test cultures of Escherichia coli, Staphylococcus aureus, Mycobacterium luteum, Candida tenuis, and Aspergillus niger. The diffusion method determined the degree of activity according to the diameter of growth inhibition zones of test cultures of microorganisms. The minimum inhibitory (MIC), bactericidal (MBC), and fungicidal (MFC) concentrations were determined by serial dilutions of the substance in a liquid nutrient medium. The alkali metal salts of 1-(hydroxyimino)naphthalene-2(1H)-one have shown the most activity against bacteria Staphylococcus aureus, Mycobacterium luteum, and fungi Candida tenuis, Aspergillus niger