固态67ZnNMR光谱研究和ab initio分子轨道计算在合成模拟的碳酸 anhydrase的合成模拟
Andrew S Lipton1, Catherine Bergquist, Gerard Parkin
1Macromolecular Structure & Dynamics Directorate, WR Wiley Environmental Molecular Sciences Laboratory, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|March 27, 2003
概括
低温固态67ZnNMR光谱显示,复合体中的四极合常数随着替代物电子负性的增加而增加. 这一发现有助于理解的活性部位,比如在碳酸中.
科学领域:
- 无机化学 无机化学 有机化学
- 固态NMR光谱学 固态NMR光谱学
- 有机金属化学 有机金属化学
背景情况:
- 三 ((pyrazolyl) 酸联体在稳定金属中心方面具有多功能.
- 复合物在生物系统中起着至关重要的作用,特别是在像碳酸无水酶这样的酶中.
- 固态NMR光谱学提供了四极核的电子环境的详细信息.
研究的目的:
- 用固态NMR研究复合物的电子性质,使用不同的替代剂.
- 为了将光谱数据与替代物电子负性相关联.
- 使用计算方法建模碳酸酸酶的活性部位.
主要方法:
- 使用了低温固态67ZnNMR光谱学.
- 三 (pyrazolyl) 酸盐复合物的合成和特征 [Tp (but,Me) ] ZnX (X = Br, Cl, OH).
- 对模型复合体的电场梯度张量进行计算计算.
主要成果:
- 的四极合常量 (Cq) 显示,随着替代物X (Br < Cl << OH) 的电子负性,的单调性增加.
- 对[Tp(But,Me) ]ZnOH的实验性NMR数据与计算结果一致.
- 对甲基利米达氧化复合物的计算,模拟碳酸无酶,与实验和计算值有很好的一致性.
结论:
- 中心的电子环境对结合替代剂的性质敏感.
- 固态67Zn核磁共振是检测有机金属复合体中的电子结构的宝贵工具.
- 该研究提供了有关生物系统的协调化学的见解.
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