The reaction of N-alkyl(aryl)-1,2(1,3)-diaminoalkanes with formaldehyde and alcohols is accompanied by condensation-heterocyclization of corresponding 1,2(1,3)-diaminoalkanes with formation of 1-alkylhydroxymethyl-3-alkyl(aryl)-1,3-diazacycloalkanes. The obtained compounds are effective aminomethylating (alkylating) agents, which opens up opportunities for synthesis of new derivatives of 1,3-diazacycloalkanes. Microbiological tests have shown high antimicrobial activity of these compounds with respect to microorganisms that degrade oil products. The antimicrobial activity has been found to depend on the nature of the nitrogen-substituent and the number of carbon atoms in the hetrocycle.When fuels, lubricating oils, and lubricating-cooling fluids (LCF) are stored and used at elevated temperatures and in moist conditions, they suffer degradation by microorganisms [1,2]. The vital activity of the latter impairs the physicochemical and performance properties of these products. One way of preventing microbiological degradation is addition to the oil products of chemical compounds that possess antimicrobial effect. A multitude of various classes of compounds intended for prevention of biodeterioration has been described in the patent and periodical literature. But because of the ability of microorganisms to adapt to oil products, it is necessary to look for and synthesize new substances that hold promise as antimicrobial additives.Earlier, N-alkylhydroxymethyl-1,3-diheterocycloalkanes (N-alkylhydroxymethyl-1,3-oxazacycloalkanes a n d 1 , 3 -b i s -a l k y l h y d r o x y m e t h y l -1 , 3 -d i a z a c y c l o a l k a n e s ) w e r e o b t a i n e d f o r t h e f i r s t t i m e b y condensation-heterocyclization of alkanolamines (or alkylenediamines) with formaldehyde and hydroxyl-bearing compounds [3,4].In the microbiological tests, these compounds were noted to have a high antimicrobial activity in relation to microflora (aerobic and anaerobic bacteria and fungi), which degrades oil products. The antimicrobial activity was found to depend on the nature of the heteroatom in the heterocycle and on the length of the chain of the alkyl substituent in the N-alkylhydroxymethyl group.In the course of the investigations and synthesis of new derivatives of 1,3-diheterocycloalkanes, we studied the reaction between N-alkyl(aryl)-1,2(1,3)-diaminoalkanes, formaldehyde, and alcohols. The starting N-derivatives of diaminoalkanes were obtained from the corresponding aminoalcohols via the stage of formation of aminobromoalkanes I, followed by reaction of the latter with primary amines:
