A pulse radiolysis study of the catalytic dismutation of superoxide ion by a superoxide dismutase model compound [Cu(aptn)](ClO4)(2)

The kinetics of catalytic dismutation of superoxide ion by N,N'-butylene bis-(2-acetyl-pyridine iminato) diperchlorate copper [Cu(aptn)]ClO4)(2) was studied by pulse radiolysis techniques. The experimental results show that the catalytic mechanism of the coordination compound is different from Cu-Zn superoxide dismutase (SOD) which is a first order reaction with regard to . O-2(-). A reverse reaction is involved here in the catalytic mechanism, namely, re-oxidation of the reduced product [Cu-1(aptn)](ClO4) can not be ignored. The rate constants k(cat), k(1), k(2) and k(-1) are reported. (C) 1997 Elsevier Science Ltd.