Antioxidant activity of aminodiarylamines in the thieno[3,2-b]pyridine series: radical scavenging activity, lipid peroxidation inhibition and redox profile

• Autor(a) principal: Calhelha, Ricardo C.
• Data de Publicação: 2014
• Outros Autores: Peixoto, Daniela, Vilas Boas, Miguel, Queiroz, Maria João R. P., Ferreira, Isabel C. F. R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/63897
• topic: Amines; Animals; Brain; Chromans; Electrochemical Techniques; Free Radical Scavengers; Linoleic Acid; Lipid Peroxidation; Nitrobenzenes; Pyridines; Structure-Activity Relationship; Swine; Thiobarbiturates; Tissue Extracts; beta Carotene; Antioxidant activity; di(hetero)arylamines; electrochemical assays; thieno[3,2-b]pyridine; Thieno[3; 2-b]pyridine; Science & Technology

The antioxidant activity of the aminodi(hetero)arylamines, prepared by C-N coupling of the methyl 3-aminothieno[3,2-b]pyridine-2-carboxylate with bromonitrobenzenes and further reduction of the obtained nitro compounds, was evaluated by chemical, biochemical and electrochemical assays. The aminodi(hetero)arylamine with the amino group ortho to the NH and a methoxy group in para, was the most efficient in radical scavenging activity (RSA, 63 µM) and reducing power (RP, 33 µM), while the aminodiarylamine with the amino group in para to the NH, gave the best results in β-carotene-linoleate system (41 µM) and inhibition of formation of thiobarbituric acid reactive substances in porcine brain cells homogenates (7 µM), with EC50 values even lower than those obtained for the standard trolox. This diarylamine also presented the lowest oxidation potential, lower than the one of trolox, and the highest antioxidant power in the electrochemical assays. The para substitution with an amino group enables higher antioxidant potential.