通过水溶性Mn(III) 氨酸二氧化物对氧化物和氧化进行区分
Marcelo A Martí1, Sara E Bari, Darío A Estrin
1Departamento de Química Inorgánica, Analítica y Qca. Física/INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab II, P. 3, Buenos Aires (C1428EHA), Argentina.
Journal of the American Chemical Society
|March 31, 2005
概括
甲皮林可以选择性地检测氧化捐赠者. 这些化合物有效地捕获氧化 (HNO),形成稳定的复合物,并使氧气具有催化循环.
科学领域:
- 无机化学 无机化学
- 生物有机化学 生物有机化学
- 化学动力学 化学动力学
背景情况:
- 氧化 (NO) 和其相关物种在生物系统中起着至关重要的作用.
- 开发选择性化学探针来区分NO和HNO对于生物和化学研究至关重要.
- 甲二烯因其氧化还原活性和潜在的催化应用而闻名.
研究的目的:
- 为了研究水溶性甲基对氧化 (NO) 和相关的HNO捐赠者的选择性反应性.
- 阐明色酸与HNO的反应机制和动力学.
- 探索这些色二烯在加工HNO捐赠体中的催化应用潜力.
主要方法:
- 在水中溶解的色素的合成和表征: (III) 中四 (N-乙烯二) 色素 (Mn (III) TEPyP) 和 (III) 中四 (tetrakis) 4-酸) 色素 (Mn (III) TPPS).
- 动力学研究以确定各种NO和HNO捐赠者的反应速率和选择性.
- 密度函数理论 (DFT) 计算以建模反应路径和中间体.
- 用光谱分析识别反应产物,例如{MnNO}{7}复合体.
主要成果:
- Mn(III) TEPyP和 Mn(III) TPPS具有很高的选择性,与HNO捐赠者快速有效地反应,与NO捐赠者反应最小.
- 与HNO捐赠体的反应导致形成一个稳定的{MnNO}(7) 复合体,其结合率常数很高 (k(on(HNO)) ≈10(5) M(-1) s(-1)).
- 动力数据和DFT计算表明HNO被Mn(III) TPPS捕获,HNO供体被Mn(III) TEPyP催化分解.
- 在氧气的存在下,Mn (II) TEPyP (NO) 产品可以重新氧化为Mn (III) TEPyP,从而允许在少量氨酸中实现高周转率.
结论:
- 溶于水的甲是有效的和有选择性的化学探针HNO.
- 不同的反应途径 (捕获与催化分解) 取决于特定的氨酸结构.
- 涉及氧气再氧化的催化循环使大量HNO捐赠物的高效处理成为可能,突出显示了在传感或排毒方面的潜在应用.
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