Aims: Detection of general patterns of the synthesis of quinazoline derivatives contains a fragment of 2-aminoalkylimidazole and studying their antimicrobial activity. Materials and Methods: Methods of organic synthesis; physical and physicochemical methods of analysis of organic compounds 1 Hydrogen nuclear magnetic resonance spectroscopy and elemental analysis were used. Results: To construct a focused library of compounds with potential antimicrobial and antifungal properties, we have chosen a strategy of combining quinazoline fragments with an imidazole residue in one molecule. The possibility of using 2-aminoalkylimidazoles as an amine component in the heterocyclization reaction with o-isothiocyanato esters was considered. 3-Substituted 2-thioxoquinazoline-4-ones were synthesized by the interaction of methyl esters of 4,5-substituted 2-isothiocyanatobenzoic acids with 2-(α,β,ω-aminoalkyl)imidazoles. Experimental study of antimicrobial activity was performed for the obtained substances, which according to the results of virtual screening showed the best results. Conclusions: A virtual library design with structural fragments of quinazoline and imidazole was made. The systematic series of 6,7-substituted 3-[2-(1H-imidazol-2-yl)-alkyl]-2-thioxo-2,3-dihydroquinazolin-4(1H)one were synthesized. According to the results of the study of the biological effects of the new derivatives of 3-N-(alkylimidazolyl-2) pyrimidine, a number of patterns of connection "chemical structure-antibacterial action" were established and the main directions of the purposeful modification of the structure for the search of new antimicrobial and antifungal agents were determined.