Unexpected Reaction Pathway of the Alpha-Aminoalkyl Radical Derived from One-Electron Oxidation of <i>S</i>-Alkylglutathiones

Abstract

Laser flash photolysis and high-resolution mass spectrometry were used to investigate the mechanism of one-electron oxidation of two S-alkylglutathiones using 3-carboxybenzophenone (3CB) as a photosensitizer. This report indicates an unexpected reaction pathway of the α-aminoalkyl radical cation (αN+) derived from the oxidation of S-alkylglutathiones. Instead of a common hydrolysis reaction of αN+ reported earlier for methionine and other sulfur-containing aminoacids and peptides, an intramolecular ring-closure reaction was found for S-alkylglutathiones.

Keywords

• <i>s</i>-alkylglutathiones
• one-electron oxidation
• laser flash photolysis
• decarboxylation