DETERMINATION OF SOD-LIKE ACTIVITY OF COPPER(II) COMPLEXES WITH ALPHA-AMINO-ACID DITHIOCARBAMATES

The SOD-like activity of the copper(II) complexes of five amino acid ( Gly, Ala, Ser, Asn, Gly) dithiocarbamates was determined. The concentr ation of the complexes that inhibit by 50% (IC50) the reduction of nit roblue tetrazolium by superoxide radical (generated by xanthine oxidas e) lies between 1.2 mu M (Glu) and 20 mu M (Gly). Quantitative structu re-activity relationships, QSAR, were established between pIC(50) (-lo g IC50) and the molar refraction values of the amino acid substituents , as well as Cu(I)/Cu(II) oxidation potentials (determined by cyclic v oltammetry). The high SOD-like activity of the Glu dithiocarbamate com plex is interrupted to be due to its distorted geometry based on EPR s pectra and conductimetric titration data. (C) 1997 Elsevier Science In c.