氧化物和HOO基之间的极快原子转移以及对催化抗氧化剂系统的影响
Andrea Baschieri1, Luca Valgimigli1, Simone Gabbanini2
1Department of Chemistry "G. Ciamician" , University of Bologna , Via S. Giacomo 11 , 40126 Bologna , Italy.
Journal of the American Chemical Society
|July 20, 2018
概括
一种使用TEMPO (2,2,6,6-四甲-1-氧基) 的新抗氧化系统通过有效地转化基来迅速阻止氧化损伤. 这种TEMPO系统比阿尔法-托科菲罗尔等天然抗氧化剂提供了更好的保护.
科学领域:
- 化学学
- 生物化学
- 抗氧化剂研究
背景情况:
- 氧化应激通过激进链反应损害生物分子.
- 脂溶性抗氧化剂如阿尔法托科菲罗尔对保护至关重要,但在某些环境中可能效果较差.
- 了解新的抗氧化机制是制定更好的保护策略的关键.
研究的目的:
- 介绍和描述基于TEMPO的新型抗氧化剂系统.
- 研究TEMPO在生物相关模型系统中灭反应性氧物种的效率.
- 将TEMPO系统的抗氧化疗效与已知抗氧化剂进行比较.
主要方法:
- 使用生物相关模型系统研究抗氧化活性.
- 涉及TEMPO,TEMPOH和基 (HOO) 的关键反应的测量速率常数.
- 将动力学数据与α-托科菲罗尔的数据进行比较.
主要成果:
- 在TEMPO系统中,可以快速将链载基转化为HOO.
- 时间有效地灭HOO,阻断氧化链反应.
- 时间介导反应的速率常数 (1.1 × 10^9 M^-1 s^-1 和 5.0 × 10^7 M^-1 s^-1) 显著超过阿尔法-托科法醇 (1.6 × 10^6 M^-1 s^-1).
结论:
- 这对TEMPO/TEMPOH建立了一个高效的还原催化循环,在脂性环境中保护有机分子.
- 这一系统为TEMPO在非水性系统中的抗氧化功效提供了新的理解.
- 作为抗激素损伤的化学保护剂,TEMPO具有潜力.
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