Determination Of Binding Parameters Of 2-(ferrocenylmethyl-amino)benzonitrile And 3-(ferrocenylmethylamino)benzo-nitrile With 1,1-diphenyl-2-picrylhydrazyl Free Radical

Abstract

Spectrophotometric techniques based assay were developed for the determination of binding parameters like binding constant and binding free energy of two potential antioxidants ferrocene derivatives: 2-(ferrocenylmethylamino)benzonitrile (2FMAB), 3-(ferrocenylmethyl-amino)benzonitrile (3FMAB), and a standard ascorbic acid (AA) with 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH). Obtained resultants indicated that the adduct 3FMBA-DPPH shows highest binding constant and highest binding free energy (2.28×105 M-1) and (-30.59 KJmol-1) respectively. Binding free energy of 3FMAB-DPPH is almost three times greater than that of the adduct 2FMAB-DPPH (-10.47 KJmol-1) and also is greater than the adduct formed between the standard antioxidant ascorbic acid and 1,1-diphenyl-2-picrylhydrazyl radicals (AA-DPPH) (-19.29 KJmol-1).