Peroxidase-like activity of an azamacrocyclic Ni(ll)complex

摘要

Peroxidase-like activity of an azamacrocyclic Ni(ll)complex,Ni(ll)(DMDAC)~(2+)(DMDAC = 1,8-dimethyl-1,3,6,8,10,13-hexaaza-cyclotetradecane = 1,8-dimethyl diazacyclam),was investigated by observing the oxidation of 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid(ABTS)in the presence of H2O2.UV/Vis and electron paramagnetic resonance spectral changes obtained from the mixture solution of Ni(ll)(DMDAC)(ClO4)2,ABTS,and H2O2 indicated that both ABTS and its oxidized form,ABTS~(+·)were the substrates of the peroxidase-like activity of Ni(ll)(DMDAC)~(2+).Current work and previously reported experimental and theoretical works on the peroxidase-like activity of azamacrocyclic Ni(ll)complexes suggest that these kind of macrocyclic Ni(ll)complexes can generally exhibit peroxidase-like activity in aqueous solution and the catalytic cycle proceeds through the heterolytic cleavage of the O-OH bond in a Ni(ll)-hydroperoxo species.