Antioxidant activity of a series of amides

Three synthesized amides: benzanilide 1,dodecanilide 2,n-cyclohexyloctamide 3,and two known ones: acetanilide 4 and n-(4-hydroxyphenyl) acetamide (acetaminophen,also known as paracetamol and tylenol) 5 were investigated for their antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (dpph) radical scavenging assay. the reduction kinetics,the effective concentration for 50% scavenging (ec50),the time required to reach the steady state of dpph discoloration at ec50 concentration (tec50) and the antiradical efficiency (are) were employed for the antioxidant activity measurement. the results revealed that this activity was more significant for fatty n- aromatic amide. of these,n-(4-hydroxyphenyl)acetamide,the one with phenol group,showed the highest antioxidant activity. the obtained results were comparable to antioxidant properties of the standard antioxidants: butylated hydroxyanisole (bha),butylated hydroxy toluene (bht) and ascorbic acid (vitamin c).