The synthesis and study of physicochemical properties of 1,2,4-triazole derivatives containing the phenethyl group in position 5

Abstract

During the last decade, national and foreign scientists have been constantly examining an example of studying the physicochemical and biological properties of nitrogen containing heterocycles, particularly with the nucleus of 1,2,4-triazole. The main advantage of such substances is to exhibit low levels of acute toxicity with a wide spectrum of pharmacological activity. To date, a large number of medicines on the basis of 1,2,4-triazole has been created, namely fluconazole, voriconazole, anastrozole, itraconazole, and letrozole. Therefore, the creation of new molecules based on 1,2,4-triazole and the search for new biologically active compounds among them is an urgent task of modern synthetic and pharmaceutical chemistry. Aim . To study some aspects of 5-phenethyl-1 H -1,2,4-triazole-3-amine reactivity and investigate the physicochemical properties of synthesized compounds. Results and discussion . A series of 1-alkyl(aryl)-N-(5-phenethyl-1 H -1,2,4-triazolе-3-yl)methanimines has been synthesized and the reaction of their reduction has been studied. The structure and purity of the synthesized compounds have been confirmed by the complex of modern instrumental methods of analysis – elemental analysis, IR, 1 H NMR spectroscopy, LC-MS. Experimental part . The reaction of 5-phenethyl-1 H -1,2,4-triazole-3-amine with aldehydes at the ambient temperature in acetic acid medium gave 1-alkyl(aryl)-N-(5-phenethyl-1 H -1,2,4-triazolе-3-yl)methanimines. At the next stage, the selective reduction of the exocyclic C=N-group of 1-alkyl(aryl)-N-(5-phenethyl-1 H -1,2,4-triazolе-3-yl)methanimines by the action of sodium borohydride in the dimethylformamide was carried out. Conclusions . 13 new 1,2,4-triazole derivatives, namely 1-alkyl(aryl)-N-(5-phenethyl-1 H -1,2,4-triazolе-3-yl)methanimines and arylmethyl-(5-phenethyl-1 H -1,2,4-triazolе-3-yl)amines, have been obtained. The both structure and purity of the obtained substances have been confirmed by the complex of modern instrumental methods of analysis. Received : 12.08.2019 Revised : 18.09.2019 Received after correction : 27.12.2019 Revised : 25.04.2020 Accepted : 29.05.2020