Antioxidant Activity of some Amidine Derivatives

Three amidines, N, N’-Diphénylbenzamidine (1), N-Cyclohexyl-N’-phényl-octamidine (2), N, N’diphényldodécamidine (3), were synthesized and investigated for their antioxidant activity using 2, 2-diphenyl-1picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP) and β-carotene/linoleic acid assays. The results indicated that amidines tested possess good antioxidant activity. Amidine 1 showed the highest radical scavenging activity, while the fatty amidine 3 showed the lowest one. Increasing the amidine concentration resulted in an increasing ferric reducing antioxidant power for all amidines tested. The reducing power of fatty amidine 3 was relatively more prominent than those of 1 and 2. Oxidation of the linoleic acid was strongly inhibited by all amidines. The obtained results were comparable to antioxidant properties of the standard antioxidants: butylated hydroxyanisole (BHA), butylated hydroxy toluene (BHT), ascorbic acid (vitamin C) and α-tocopherol (vitamin E).