循环子对基的自旋捕获的理论研究:密度函数理论方法
Frederick A Villamena1, Christopher M Hadad, Jay L Zweier
1Center for Biomedical EPR Spectroscopy and Imaging, College of Medicine, Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA. villamena-1@medctr.osu.edu
Journal of the American Chemical Society
|February 12, 2004
概括
研究人员探索了新的旋转陷来检测基基 (*OH),氧化应激的关键参与者. 化子对更稳定的添加物有希望,有助于激素检测和理解生物过程.
科学领域:
- 化学 化学 化学
- 生物化学 生物化学
- 频谱学是一种光谱学.
背景情况:
- 基 (*OH) 是生物氧化应激的一个关键媒介.
- 准确检测*OH对于理解氧化损伤至关重要.
- 旋陷,如5,5-二甲基-1-氨酸N-氧化物 (DMPO),与电子磁共振 (EPR) 光谱用于激素检测.
研究的目的:
- 通过计算来评估新的子旋转陷,以提高基基 (*OH) 的检测能力.
- 为了比较各种子替代剂在捕获*OH中的效率和稳定性.
- 为了将子的电子和结构性质与它们的旋 adduct 稳定性相关联.
主要方法:
- 在B3LYP/6-31+G//B3LYP/6-31G水平的密度函数理论 (DFT) 计算被用来优化子几何形状和计算引能.
- 在子旋转陷上分析电荷和旋转密度.
- 各种子衍生物的二面角和热力学性能的比较.
主要成果:
- 与碳化类似物相比,化子与*OH形成了更多的外能添加物.
- 对于醇基碳酸子,转 adducts 是受青的,而对于醇基酸子,具有分子内H键的 cis adducts 是受青的.
- 胺基和螺旋酸具有与酸酸酸相似的特性,这表明它们适合用于*OH自旋捕获.
结论:
- 化子,特别是那些在C-5处具有二甲基酸替代的子,为*OH检测产生最稳定的自旋添加物.
- 氨基酸和螺旋酸是OH自旋捕获的有希望的替代品.
- 计算分析为设计改进的子旋转陷提供了基础,用于氧化应激研究.
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