基配对对氨酸电化学氧化的作用
Cyrille Costentin1, Viviane Hajj, Marc Robert
1Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université-CNRS No. 7591, Université Paris Diderot, 75205 Paris Cedex 13, France.
Journal of the American Chemical Society
|July 6, 2010
概括
氨酸基配对对关氨酸的电化学氧化产生最小的影响. 反应机制涉及离子基的形成,去质子化和二元化,而不是协调的质子-电子转移.
科学领域:
- 电化学 电化学 电化学
- 生物物理化学 生物物理化学
- 有机化学 有机化学
背景情况:
- 关氨酸氧化在生物和化学过程中至关重要.
- 了解氨酸电化学上的基配对效应是关键.
- 结合影响分子相互作用和反应性.
研究的目的:
- 为了研究瓜的电化学氧化.
- 确定氨酸基配对对氨酸氧化动力学和热力学的影响.
- 为了阐明在基配对伙伴的存在下瓜氧化反应的反应机制.
主要方法:
- 循环电压测量被用来研究瓜氧化.
- 在 (CHCl3) 中进行了反应,以促进结.
- 为了分离基配对效应,与加重基 (2,6-卢提丁) 进行了比较.
主要成果:
- 氨酸基配对对氨酸氧化热力学和动力学的影响很小.
- 反应机制不涉及协调的质子电子转移,由H/D同位素效应的缺乏证明.
- 该机制通过决定速率的阴离子基的形成进行,其次是去质子化和基的二元化或进一步的氧化.
结论:
- 氨酸的基配对不会显著改变瓜的电化学氧化途径.
- 关氨酸的电化学氧化涉及一个逐步的电子转移和脱质过程.
- 溶剂和基配对相互作用在研究的瓜氧化反应中起到有限的作用.
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