The synthesis of 3-methyl-6-R-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives

Abstract

Aim. To conduct the synthesis and confirm the structure of 3-methyl-6-R-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives as potential biologically active compounds. Results and discussion. It has been shown that the heterocyclization reaction of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol with carboxylic acids in the excess of phosphorus oxychloride yields 3-methyl-6-R-[1,2,4]-triazolo[3,4-b][1,3,4]thiadiazoles. Experimental part. The reaction of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol with the corresponding carboxylic acids was carried out in the excess of phosphorus oxychloride. The mixture was heated for 5 h with subsequent cooling and neutralization to pH 7 using ammonia solution. 1H NMR spectra of the compounds synthesized were recorded on a Varian Mercury VX-200 spectrometer operating at a frequency of 200 MHz, in DMSO-d6, using tetramethylsilane (TMS) as an internal standard. Melting points were measured using a MPA100 device. The elemental analysis was performed on a Elementar Vario EL Cube elemental analyzer. Agilent 1260 Infinity HPLC System equipped with Agilent 6120 mass spectrometer were used for registering LC-MS data. Conclusions.As a result of this study 10 new compounds of the 3-methyl-6-R-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole series have been obtained. The structure and purity of the products have been confirmed using 1Н NMR spectroscopy, LC-MS and elemental analysis.

Keywords

• synthesis
• triazoles
• physicochemical properties