Abstract Searching for bioactive compounds from natural products to antioxidative drugs, polyphenols type stilbenoids and flavonoids are recognized as useful candidates. The current study aims to elucidate the promising antioxidative capacity of two previously undescribed compounds silbenoid suaveolensone A (1) and flavonoid suaveolensone B (2), which mainly based upon DFT computational method. The antioxidant actions of both two studied compounds 1-2 is due to OH bond disruption, and followed by HAT mechanism in gas, but SPLET model in solvents acetone, methanol, and water. Structural and electronic analyses point out the role of aromatic phenyl units in antioxidative reactions. They respond for the more delocalization of electrons, thereby facilitating antiradical reactions. From the kinetic reaction of HOO• radicals attack OH groups, flavanonol 2 is better than stilbenoid 1 in antioxidative treatment, in which the lower Gibbs activation energies ΔG# of 9.8 - 12.9 kcal/mol and the higher rate constants K of 8.266 × 106 - 2.946 × 108 L/mol.s of compound 2 compared to those of compound 1 (the ΔG# values of 11.2 - 25.3 kcal/mol and the K values of 1.946 × 101 - 6.297 × 107 L/mol.s)

中文翻译：

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芪类 Suaveolensone A 和黄酮类 Suaveolensone B 的抗氧化能力：结构电子特性和机制的详细分析

摘要 寻找从天然产物到抗氧化药物的生物活性化合物，多酚类芪类和黄酮类化合物被认为是有用的候选物。目前的研究旨在阐明两种以前未描述的化合物 silbenoid suaveolensone A (1) 和黄酮类 suaveolensone B (2) 的有希望的抗氧化能力，这主要基于 DFT 计算方法。两个研究的化合物 1-2 的抗氧化作用是由于 OH 键断裂，在气体中遵循 HAT 机制，但在溶剂丙酮、甲醇和水中的 SPLET 模型。结构和电子分析指出芳香苯基单元在抗氧化反应中的作用。它们响应电子的更多离域，从而促进反自由基反应。从 HOO• 自由基攻击 OH 基团的动力学反应来看，