• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Dynamics by solid-state NMR: Detailed study of ibuprofen Na salt and comparison with ibuprofen
【24h】

Dynamics by solid-state NMR: Detailed study of ibuprofen Na salt and comparison with ibuprofen

机译：固态NMR动力学：布洛芬钠盐的详细研究以及与布洛芬的比较

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The various internal rotations and interconformational jumps of the Na-salt form of ibuprofen in the solid state were characterized in detail by means of the simultaneous analysis of a variety of low- and high-resolution NMR experiments aimed at measuring several ~(13)C and ~1H spectral and relaxation properties at different temperatures and frequencies. The results were first qualitatively analyzed to identify the motions of the different molecular fragments and to assign them to specific frequency regimes (slow, <10~3 Hz; intermediate, 10~3-10~6 Hz; and fast, >10~6 Hz). Subsequently, a simultaneous fit of the experimental data sets most sensitive to each frequency range was performed by using suitable motional models, thus obtaining, for each motion, correlation times and activation energies. The motions so characterized were: the rotations of the three methyl groups and of the isobutyl group, occurring in the fast regime, and the π-flip of the phenyl ring, belonging to the intermediate motional regime. The results obtained for the Na-salt form were compared with those of the acidic form of ibuprofen, previously obtained from a similar solid-state NMR approach: despite the very similar chemical structure of the two compounds, their dynamic properties in the solid state are noticeably different.
机译：通过同时分析旨在测量多个〜（13）C的各种低分辨率和高分辨率NMR实验，详细表征了布洛芬钠盐形式的固态的各种内旋和构象跃迁和在不同温度和频率下的〜1H光谱和弛豫特性。首先对结果进行定性分析，以鉴定不同分子片段的运动，并将它们分配给特定的频率范围（慢，<10〜3 Hz;中，10〜3-10〜6 Hz;快，> 10〜6赫兹）。随后，通过使用合适的运动模型同时对每个频率范围最敏感的实验数据集进行拟合，从而为每个运动获得相关时间和激活能。如此表征的运动是：在快速状态下发生的三个甲基和异丁基的旋转，以及属于中间运动状态的苯环的π翻转。将钠盐形式的结果与布洛芬的酸性形式的结果进行了比较，后者以前是通过类似的固态NMR方法获得的：尽管两种化合物的化学结构非常相似，但它们在固态时的动态特性却是明显不同。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号