Acid-Base Equilibrium of a 6-Methyluracil Derivative with 1,2,3-Triazole Fragment in Aqueous Solutions

The constants and thermodynamic characteristics of the acid-base equilibrium between the first synthesized 6-methyluracil derivative with a 1,2,3-triazole ring at the C(5) atom of the uracil ring—5-(1-pentyl-4-methyl-1,2,3-triazol-4-yl)-6-methyluracil ( 1 )—and its model compound 5,6-dimethyluracil were determined by potentiometric titration in aqueous solutions. It was shown that the 1,2,3-triazole ring does not significantly affect the acid-base properties of the uracil fragment in compound 1 . The deprotonation sites of compound 1 in aqueous alkaline and DMSO solutions were suggested. The structure of compound 1 was proved by NMR and IR spectroscopy and elemental analysis.