控制克劳兰酸和青酸之间的内在化学反应率差异的因素
Yen-lin Lin1, Nai-yuan Chang, Carmay Lim
1Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan, Republic of China.
Journal of the American Chemical Society
|October 3, 2002
概括
克拉酸 (Clav) 由于其独特的化学结构,可以比青素-G更好地抑制β-乳酸酶. 计算方法揭示了克拉夫.
科学领域:
- 药用化学 医学化学
- 计算化学的计算化学
- 生物化学 生物化学
背景情况:
- 细菌β-lactamase酶使penicillin-G无活化,这是一个重要的抗生素.
- 克拉酸 (Clav) 是一种β-乳糖酶抑制剂,其结构类似于青素-G.
- 了解克拉夫的抑制活性的化学基础是对抗抗生素耐药性的关键.
研究的目的:
- 阐明青素-G和克拉夫兰酸 (Clav) 之间的化学反应性差异.
- 确定Clav作为β-乳酸酶抑制剂有效性的因素.
- 评估环状菌株在β-乳酸抗生素活性中的作用.
主要方法:
- 使用了ab initio和连续介电计算方法.
- 计算了Clav和青酸 (Peni) 的性水解的自由能量概况.
- 计算了乳和五个环的环应变能量.
主要成果:
- 克拉夫兰酸 (Clav) 水解产生比青酸 (Peni) 更稳定的产品.
- 由于增强的静电相互作用和环开放促进,Clav比Peni更快地经历基本水解.
- 在β-乳酸或五个成员环中的环应变不会显著提高性水解速率.
结论:
- 克拉夫中的O1原子和基乙基增强了其对β-lactamases的抑制活性.
- 克拉夫的更快的水解是由于碳C7原子的正电荷增加,并促进了环开放.
- 内在环应变不是这些β-乳酸分子中性水解的主要驱动因素.
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