BIOCIDAL ACTIVITY OF AMINOMETHYL DERIVATIVES OF 2-MERCAPTOBENZOXAZOLE

The biocidal activity of the aminomethyl derivatives of 2-mercaptobenzoxazole synthesized by us and being of interest as potential antimicrobial additives to petroleum products and cutting fluids, was studied. The aminomethylation reaction proceeded with the participation of methylene-bis-amines. As a result, the appropriate N-substituted benzoxazolin-2-thiones were obtained. Their structure was proved by NMR 1H. Due to the poor solubility of the synthesized compounds in petroleum products, their salts with petroleum naphthenic acid were obtained for microbiological testing. The results of tests in lubricating oil M-8 show that the naphthenic salts of the synthesized compounds exhibit biocidal activity and their fungicidal properties are higher than bactericidal ones. The petroleum naphthenic acid used in the test in its pure form in the composition of the M-8 lubricating oil is not biostable and is affected by microorganisms. N-piperidinomethylbenzoxazolin-2-thione in the composition of the coolant proved to be a biocide, and its bactericidal properties are higher than fungicidal ones. The results of a microbiological study of an aqueous solution of this compound showed high bactericidal properties in the absence of effectiveness against mold fungi.