Reactions of Fe(II)-ATP and Fe(II)-citrate complexes with t-butyl hydroperoxide and cumyl hydroperoxide

AbstractRate constants for the reactions of cumyl hydroperoxide and t-butyl hydroperoxide with ferrous complexes of ATP and citrate were measured at pH 7.4. These ligands are potential chelators of iron(II) in the low-molecular weight iron pool that may catalyze oxidative degradation of biomolecules. The second-order rate constants for the reduction of cumyl hydroperoxide and t-butyl hydroperoxide by ferrous ATP are 3.1 × 103 and 1.3 × 103 M−1·s−1, respectively, at 25°C and 0.11 M ionic strength. Rates of reduction by ferrous citrate are similar. Activation enthalpies for these reactions average 10 kcal/mol