使用四极NMR晶体学指导的晶体结构预测的以弗得林HCl和伪以弗得林HCl的表征
Carl H Fleischer1,2, Sean T Holmes1,2, Kirill Levin3
1Department of Chemistry & Biochemistry, Florida State University, Tallahassee, FL 32306, USA. rschurko@fsu.edu.
Faraday discussions
|September 23, 2024
概括
四极核磁共振晶体学指导的晶体结构预测 (QNMRX-CSP) 成功确定了复杂有机酸盐的晶体结构,包括剂型中的盐. 这一进步将QNMRX-CSP的实用性扩展到简单分子之外.
科学领域:
- 固态NMR光谱学 固态NMR光谱学
- 晶体学 晶体学是指结晶学.
- 计算化学是一种计算化学.
背景情况:
- 四极核磁共振晶体学指导的晶体结构预测 (QNMRX-CSP) 是一种用于晶体结构确定的新兴协议.
- 以前的应用仅限于使用35Cl EFG张量数据的小型,刚性有机HCl盐.
研究的目的:
- 将QNMRX-CSP扩展到更大,更灵活的二聚体化合物 (乙烯HCl和伪乙烯HCl).
- 通过对实验数据进行基准测试和探索起始模型和晶体学参数的影响来验证QNMRX-CSP.
- 通过预测Sudafed®中伪乙烯HCl的结构来证明QNMRX-CSP在分析药物配方方面的潜力.
主要方法:
- 利用来自四极核素的固态NMR数据.
- 包含DFT-D2*计算中的静态格子能量和电场梯度 (EFG) 张量.
- 综合粉末X射线衍射 (PXRD) 数据用于结构验证.
主要成果:
- 成功地将QNMRX-CSP应用于以弗得林HCl和伪以弗得林HCl,它们具有不同的空间组和灵活的有机成分.
- 基准测试揭示了启动结构模型和单元细胞参数和空间组的选择的影响.
- 仅使用35Cl SSNMR数据,预测了Sudafed®剂型中的伪乙烯HCl晶体结构.
结论:
- QNMRX-CSP有效地扩展到更复杂的有机HCl盐.
- 该协议显示,它有望解决药剂形式中的活性药物成分的晶体结构,克服传统方法的局限性.
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