Enhancement of the rate of the β-elimination of phosphate from radicals derived from glycerol-2-phosphate by Cu(I)-phenanthroline. A pulse radiolysis study

Abstract

Hydroxyl radicals abstract hydrogen atoms from glycerol-2-phosphate with a specific rate constant of (7.0 ± 1.5) × 10 8 M −1s −1 forming the β-phospho radical as the major product. At physiological pH this radical undergoes a β-phosphate elimination with a rate constant ≤ 1 × 10 3 s −1. The β-phospho radical reacts with CU(I)-phenanthroline to produce an unstable transient with a metal-carbon σ-bond which has an absorbance similar to that of the cuprous phenanthroline complex in the visible region. This intermediate decomposes via a β-elimination of phosphate with a rate constant of 1.0 ± 1.5) × 10 4s −1, which was independent of the acidity in the pH range 4–9.