Microwave-assisted synthesis of some new derivatives of 4-substituted-3-(morpholinomethyl)-4H-1,2,4-triazole-5-thioles

Abstract

Objective: The purpose of this work is to synthesize new series of 4-((5-((cyclohexylmethyl)thio)-4-R1-4H-1,2,4-triazol-3-yl)methyl)morpholines and 4-((4-R1-5-(pyridin-2-ylthio)-4H-1,2,4-triazol-3-yl)methyl)morpholines using a microwave synthesis system. Material and Method: As starting compounds are used 4-R1-3-(morpholinomethyl)-4H-1,2,4-triazole-5-thioles (where, R1=H, methyl, ethyl, phenyl, amino). Synthesis was carried out using a microwave synthesis system Milestone Flexi Wave. The structure of synthesized compounds is confirmed by the use of modern methods of analysis 1H NMR, 13C NMR spectroscopy, elemental analysis and gas chromatography–mass spectrometry (GS/MS). Result and Discussion: As a result of the conducted experiment, the synthesis method is optimized for 4-((5-((cyclohexylmethyl)thio)-4-R1-4H-1,2,4-triazol-3-yl)methyl)morpholines and 4-((4-R1-5-(pyridin-2-ylthio)-4H-1,2,4-triazol-3-yl)methyl)morpholines by microwave irradiation. It was established that the reactions proceed to the end in all described conditions, but the reaction with the parameters t=10 min, T=160 оС is the most technologically optimal. This approach has allowed reducing energy costs and increasing the yield of target compounds. As a result, a class of new derivatives of 1,2,4-triazole has been obtained, which can be used in further pharmacological studies as valuable biological agents.