迪亚里尔迪塞利尼德的氨酸过氧化酶类抗氧化活性:一个机理学研究
1Department of Chemistry and the Biotechnology Centre, Indian Institute of Technology, Powai, Bombay 400 076, India.
Journal of the American Chemical Society
|July 18, 2001
概括
具有分子内氨基基群的二甲基脱化物表现出强烈的醇过氧化酶活性. 它们的抗氧化疗效由-相互作用的强度调整,影响类似于谷氨过氧化酶的催化机制.
科学领域:
- 有机金属化学 有机金属化学
- 生物化学 生物化学
- 抗氧化剂研究 抗氧化剂研究
背景情况:
- 迪亚里尔脱化物因其抗氧化性质而受到研究.
- 内分子协调氨基群影响有机化合物的活性.
- 氨酸过氧化酶 (GPx) 是细胞抗氧化防御中的一个关键酶.
研究的目的:
- 为了合成和表征具有分子内氨基基群的二甲基脱化物.
- 为了评估它们的醇过氧化酶类抗氧化活性.
- 阐明有机中间体和Se-N相互作用的机械作用.
主要方法:
- 迪亚里尔脱化物的合成,包括对抗分子纯粹的形式.
- 使用 (77) Se NMR光谱在现场表征中间体.
- 对过氧化酶活性的测定和涉及醇和过氧化的机制研究.
主要成果:
- 从R-(+) - 和S-(-) -N,N-dimethyl(1-ferrocenylethyl) amine衍生而成的超分子纯净的迪亚里尔脱化物显示出出色的过氧化酶活性.
- 活性是由分子内Se-N相互作用的程度调节的.
- 强烈的Se-N相互作用通过抑制前进的催化循环,导致不活跃的disenenides.
- 弱Se-N相互作用通过有效形成单中间体来增强活性.
- 未被替代的二二化物由于反应缓慢和中间不稳定性而表现出较低的活性.
结论:
- 分子内Se-N相互作用是二甲酸脱化过氧化酶活性的一个关键决定因素.
- 催化机制涉及到单,单酸和单硫化物中间体.
- 这些合成的脱化物模仿了天然的谷氨过氧化酶的催化循环.
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