在激活一个enediyne时的 conformational控制
M F Semmelhack1, Lingyun Wu, Robert A Pascal
1Department of Chemistry, Princeton University, Princeton, NJ 08544, USA. mfshack@princeton.edu
Journal of the American Chemical Society
|August 28, 2003
概括
计算研究预测bicyclo[7.3.1]tridec-4-ene-2,6-diyne的椅子构造器更具反应性. 合成一个桥接衍生品证实了这一点,显示引发了enediyne毒素的循环芳香化.
科学领域:
- 有机化学 有机化学
- 计算化学计算化学
- 药用化学 医学化学
背景情况:
- 双循环[7.3.1]tridec-4-ene-2,6-diyne框架是calicheamicin的核心,这是一个强大的enediyne毒素.
- 了解这种框架的结构动态和反应性对于药物设计和理解毒素机制至关重要.
研究的目的:
- 通过计算来研究自行车[7.3.1]tridec-4-ene-2,6-diyne框架对循环芳香化相对反应的椅子和船的相对反应性.
- 通过合成和研究结构锁定导数来实验验证计算预测.
主要方法:
- 密度函数理论 (DFT) 的计算被用来建模电子结构,并预测不同对象的反应性.
- 合成一个功能化的bicyclo[7.3.1]tridec-4-ene-2,6-diyne衍生物与一个两原子桥以强制执行船形.
- 动力学研究,以确定在释放形状锁时循环芳香化速率.
主要成果:
- DFT的计算表明,椅子形容器对循环芳香化反应明显比船形容器更强.
- 一个合成的衍生品,锁定在船形状中,在室温下稳定.
- 桥梁的裂启动了循环芳香化,在23°C下半衰期为42.5分钟,通过椅子形状来支持拟议的机制.
结论:
- 实验结果证实了关于椅子调整器更高反应率的计算预测.
- 这项研究引入了一种新的策略,通过构造控制触发enediyne毒素活性,这对开发新的治疗剂或了解天然产品机制具有影响.
相关概念视频
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