Reactivity of Electrogenerated Superoxide Ion II．Correlation between Stability and Reactivity of Superoxide Ion

Ambident reactivity of the nitrite ion revisited.

Nucleophilic reactivity of a copper(II)-superoxide complex.

Metal-bound superoxide intermediates are often implicated as electrophilic oxidants in dioxygen-activating metalloenzymes. In the nonheme iron α-ketoglutarate dependent oxygenases and pterin-dependent hydroxylases, however, Fe(III)-superoxide intermediates are postulated to react by nucleophilic attack on electrophilic carbon atoms. By reacting a Cu(II)-superoxide complex (1) with acyl chloride...

Validation of a new method using the reactivity of electrogenerated superoxide radical in the antioxidant capacity determination of flavonoids.

This article lays out a new method to measure the antioxidant capacity of some flavonoids. The methodology developed is based on the kinetics of the reaction of the antioxidant substrate with the superoxide radical (O(2)(*-)). A cyclic voltammetric technique was used to generate O(2)(*-) by reduction of molecular oxygen in aprotic media. In the same experiment the consumption of the radical was...

Effect of increased sodium ion on arterial sodium and reactivity.

1. Isolated rabbit arterial segments were perfused with buffer containing sodium (1 55 mmol/l) and vasoconstrictor responses to noradrenaline, histamine and electrical stimulation were measured. When the concentration of sodium in the perfusing medium was raised by 8 mmol/l, the vasoconstrictor responses to all stimuli were significantly increased, though response to electrical stimulation was ...

Direct detection and reactivity of the short-lived phenyloxenium ion.

Photolysis of protonated phenylhydroxylamine was studied using product analysis, trapping experiments, and laser flash photolysis experiments (UV-vis and TR(3) detection) ranging from the femtosecond to the microsecond time scale. We find that the excited state of the photoprecursor is followed by two species: a longer-lived transient (150 ns) that we assign to the phenoxy radical and a shorter...