Asgarshamsi Mohammad Hossein, Fassihi Afshin, Hassanzadeh Farshid, Saghaei Lotfollah, Attar Ahmad Movahedian, Mohammad-Beigi Hossein
Department of Medicinal Chemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran.
Department of Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran.
Res Pharm Sci. 2020 Dec 30;16(1):35-47. doi: 10.4103/1735-5362.305187. eCollection 2021 Feb.
Radicals produced by Fenton and Haber-Weiss reactions play detrimental roles in our body. Some oxidized proteins as toxic configurations are identified in amyloid-β deposits. These deposits mostly occur in conditions, such as Alzheimer's disease. Here, we report the synthesis, evaluation of the antioxidant activity, and implementation of density functional theory (DFT) calculations of some4- [(benzo[]thiazol-2-ylimino) methyl]phenol derivatives. The aim of this study was to provide a comparative theoretical-experimental approach to explain the antioxidant activities of the compounds.
Compounds were synthesized by the reaction between hydroxybenzaldehyde and aminobenzothiazole derivatives. The scavenging activity of the compounds was evaluated. Various electronic and energetic descriptors such as high occupied molecular orbital and low unoccupied molecular orbital energy gaps, bonding dissociation enthalpy of OH bond, ionization potential, electron affinity, hardness, softness, and spin density of the radical and neutral species were calculated. DFT calculations with B3LYP hybrid functional and 6-311++ G** basis set in the polarizable continuum model were utilized to obtain these descriptors.
FINDINGS/RESULTS: Ascorbic acid showed the best DPPH scavenging activity. However, and showed promising antioxidant activity. The values of EHOMO for and were closer to zero, thus, they showed the best scavenging activities. The computational results were in accordance with the experimental ones. The energetic descriptors indicated that the sequential proton loss-electron transfer mechanism is preferred over other mechanisms.
Antioxidant activity of 4-[(Benzo[]thiazol-2-ylimino) methyl]phenol derivatives confirmed by experimental and theoretical documents proves them as novel antioxidants against amyloid-β based disease.
芬顿反应和哈伯-维伊斯反应产生的自由基对我们的身体具有有害作用。在淀粉样β蛋白沉积物中发现了一些具有毒性构型的氧化蛋白。这些沉积物大多出现在诸如阿尔茨海默病等病症中。在此，我们报告了一些4 - [(苯并噻唑-2-基亚氨基)甲基]苯酚衍生物的合成、抗氧化活性评估以及密度泛函理论（DFT）计算的实施情况。本研究的目的是提供一种比较理论-实验方法来解释这些化合物的抗氧化活性。
通过羟基苯甲醛与氨基苯并噻唑衍生物之间的反应合成化合物。评估了这些化合物的清除活性。计算了各种电子和能量描述符，如最高占据分子轨道和最低未占据分子轨道能隙、OH键的键解离焓、电离势、电子亲和势、硬度、软度以及自由基和中性物种的自旋密度。利用在极化连续介质模型中采用B3LYP混合泛函和6 - 311++G**基组的DFT计算来获得这些描述符。
抗坏血酸表现出最佳的DPPH清除活性。然而，[具体化合物1]和[具体化合物2]表现出有前景的抗氧化活性。[具体化合物1]和[具体化合物2]的EHOMO值更接近零，因此，它们表现出最佳的清除活性。计算结果与实验结果一致。能量描述符表明，顺序质子损失-电子转移机制优于其他机制。
实验和理论文献证实的4 - [(苯并噻唑-2-基亚氨基)甲基]苯酚衍生物的抗氧化活性证明它们是针对基于淀粉样β蛋白的疾病的新型抗氧化剂。
