The role of copper(II) ions in the oxidation of 5-hydroxy-6-methyluracil in the ground and electronically excited states with molecular oxygen in aqueous solutions


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

A spectral fluorescence study of photoinduced reactions in aqueous solutions has been carried out in order to examine the mechanisms of the oxidation of 5-hydroxy-6-methyluracil (I) in the ground and electronically excited states by molecular oxygen in the presence of copper(II) chloride. It has been found that 5,5,6-trihydroxy-6-methylpyrimidine-2,4-dione (II) is formed upon the photolysis of I. The spectral parameters (λmax) and the quantum yields (φ) of fluorescence (FL) of compounds I (φ = 8 × 10–4; λmax = 362 nm) and II (φ = 17 × 10–4; λmax = 306, 330 nm) have been determined. A reaction scheme was proposed, according to which the photooxidation of I occurs through the steps of the generation of the radical cation I•+ and the superoxide anion О2•- with the subsequent formation of 5,5,6-trihydroxy-6-methylpyrimidine-2,4-dione. The catalytic and inhibitory effects of Cu(II) ions on the oxidation of 5-hydroxy-6-methyluracil in the ground and electronically excited states, respectively, by the oxygen radical anion О2•- have been revealed.

About the authors

S. S. Ostakhov

Institute of Organic Chemistry, Ufa Scientific Center

Author for correspondence.
Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

S. L. Khursan

Institute of Organic Chemistry, Ufa Scientific Center

Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

Yu. I. Murinov

Institute of Organic Chemistry, Ufa Scientific Center

Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

T. R. Nugumanov

Institute of Organic Chemistry, Ufa Scientific Center

Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

R. R. Kayumova

Institute of Organic Chemistry, Ufa Scientific Center

Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

S. F. Petrova

Institute of Organic Chemistry, Ufa Scientific Center

Email: chemlum@anrb.ru
Russian Federation, Ufa, 450054

Supplementary files

Supplementary Files
Action
1. JATS XML

Copyright (c) 2017 Pleiades Publishing, Ltd.