Acid-Base Properties of 5-Hydroxy-1,3,6-trimethyluracil in Aqueous Solutions

5-Hydroxy-1,3,6-trimethyluracil has been studied using 1H, 13C, and 15N NMR as well as UV spectroscopy. The constants and thermodynamic characteristics of its acid-base equilibrium in aqueous solutions have been determined. The stepwise mechanism of 5-hydroxy-6-methyluracil dissociation in aqueous solutions has been elucidated.