Antioxidant and antimicrobial activities of two amidine derivatives

Two substituted amidines, N , N' -diphenylbenzamidine 1 and N , N' -diphenyldodecamidine 2 , were investigated in vitro for their antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay under kinetic process , as well as for their antimicrobial activity against some strains of bacteria and fungi. The antioxidant propriety was assessed by the effective concentration of the amidine (EC 50 ), the time required to reach the steady state of DPPH discoloration at EC 50 (t EC50 ), the antiradical efficiency (ARE) and the reduction kinetics. The highest value of radical scavenging activity was obtained for amidine 1. Overall, the two amidines showed a moderate activity against Gram-negative Salmonela enteric with amidine 2 being more effective. The latter amidine exhibited also a potent inhibition against Gram-negative Pseudomonas aeruginosa and an antifungal activity against Mucor ramannianus .