The Application of Novel Electrochemical Approach to Antioxidant Activity Assay of Metal Porphyrins with Bulky 3,5-Diisobornyl-4-hydroxyphenyl Moieties

Abstract

The complexes of biogenic metals ( )Zn Cu Co Mn Febased on meso-tetra(3,5-diisobornyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these compounds was studied using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The antioxidant activity of complexes was estimated by means of the electrochemical assay based on the hydrogen atom transfer reaction to the stable radical 2,2'-diphenyl-1-picrylhydrazyl (DPPH). The RDE method was applied for this process monitoring. It was shown that the efficiency of the metal complexes ( )Cu Co Mn Ni Feis practically the same order as that of free base porphyrin 1. However the Zn 2+ complex demonstrates significantly higher antioxidant activity, and the stoichiometry of the reaction was determined as σ = 4. The results demonstrate that porphyrin macrocycle can directly affect the antioxidant properties of 2,6-diisobornylphenol.

The electrochemical approach to antioxidant activity assay of metal complexes with dipicolylamine ligand, containing 2,6-di-tert-butylphenol groups, based on electrochemical DPPH-test

“…Recently we proposed the novel approach to monitoring the reaction with DPPH by cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques [34][35][36][37][38]. In [39] this method was successfully applied to study of substituted tetraphenyporphyrines antioxidant activity.…”

The Antioxidant Properties of Asymmetrically Substituted Tetra(meso-aryl)porphyrins with One Phenolic Substituent: The Contribution of Phenol and Porphyrin Fragments to Antioxidant Activity

“…В большинстве случаев это тетра(мезо-арил)порфирины с четырьмя фенольными фрагментами, непосредственно связан-ными с макроциклом. [8][9][10][11][12][13][14][15][16][17] Как известно, замещенные фенолы относятся к наиболее широко используемым антиоксидантам, эффективность которых возрастает с увеличением числа электронодонорных заместителей, введенных в орто-или пара-положения к ОН-группе. Порфириновый макроцикл также взаимодействует со свободными радикалами.…”

A New Strategy for the Synthesis of Porphyrin and Expanded Porphyrin Derivatives from Di‐ and Tripyrromethanes: Antioxidant, Cytotoxic Activity, and Molecular Docking Evaluation

“…The obtained antioxidant activity data showed that the aromatic ring bearing electron‐donating substituents increases the antioxidant activity however, electron‐withdrawing substituents decrease it [29] . The higher potency of 6 g as an antioxidant agent may be attributed to the presence of phenolic OH group and strong electron donating t‐butyl groups [30–35] . Similarly, the presence of electron donation OH groups increases the antioxidant activity of 6 h .…”

“…[29] The higher potency of 6 g as an antioxidant agent may be attributed to the presence of phenolic OH group and strong electron donating tbutyl groups. [30][31][32][33][34][35] Similarly, the presence of electron donation OH groups increases the antioxidant activity of 6 h. Electronwithdrawing substituents as the chlorine atom and nitro group in 6 f, and carboxylic groups in 6 b decrease their antioxidant activity.…”