Enhanced measurement of anisotropic NMR parameters using tunable alignment strength and tensor orientation

使用可调对准强度和张量方向增强各向异性 NMR 参数的测量

• 批准号: 71001274
• 负责人: Professor Dr. Burkhard Luy
• 金额: --
• 依托单位: Institut für Organische Chemie (IOC)
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/71001274?language=en
• 关键词: Enhanced; measurement; anisotropic; NMR; parameters

Next to established isotropic NMR parameters like chemical shifts, scalar couplings, and NOEs, the in-troduction of weakly oriented samples allows the measurement of anisotropic NMR parameters like re-sidual dipolar couplings (RDCs). The principle technique and its large potential in structure determination of molecules is already known since 1963 but only recent developments in sample preparation made RDCs widely available for complex organic compounds. The various RDCs in organic compounds vary substantially in size, with 2DHH and 1DCH as the largest and nDCC and 1DCN among the smallest (up to 50 times smaller) useful couplings, making an adjustable alignment without change of sample conditions highly desirable. Two techniques for varying the alignment strength, variable angle NMR and an elas-tomer-based stretching apparatus, during the first funding period have been developed to the point where they can be used routinely. The aim of the proposed research is now the development of corre-sponding pulse sequences for efficient measurement of long-range heteronuclear and carbon-carbon couplings. A second objective is pursued with the development of composite alignment media, having a liquid crystalline component fixed inside a gel, which will allow tuning of the alignment tensor orientation of molecules and thereby resolve signal overlap and random degeneracies of RDCs. All techniques de-veloped will first be applied to test molecules and then be used for the structure determination of natural products and other chemically and/or biologically interesting molecules.

除了已建立的各向同性NMR参数（如化学位移、标量耦合和NOE）外，弱取向样品的引入还允许测量各向异性NMR参数（如残余偶极耦合（RDC））。自1963年以来，分子结构测定的原理技术及其巨大潜力就已为人所知，但直到最近样品制备的发展才使RDC广泛用于复杂有机化合物。有机化合物中的各种RDC在大小上变化很大，其中2DHH和1DCH是最大的，nDCC和1DCN是最小的（小50倍）有用的耦合，使得在不改变样品条件的情况下可调节的对齐非常理想。在第一个资助期内，两种用于改变排列强度的技术，即变角NMR和基于弹性体的拉伸装置，已经发展到可以常规使用的程度。目前，拟议研究的目标是开发相应的脉冲序列，用于有效测量远程异质结和碳-碳耦合。第二个目标是追求复合取向介质的发展，具有固定在凝胶内的液晶组分，这将允许调整分子的取向张量取向，从而解决RDC的信号重叠和随机简并。所有这些技术将首先应用于测试分子，然后用于天然产物和其他化学和/或生物学上感兴趣的分子的结构测定。

项目成果

Homonuclear BIRD-decoupled spectra for measuring one-bond couplings with highest resolution: CLIP/CLAP-RESET and constant-time-CLIP/CLAP-RESET.

• DOI: 10.1016/j.jmr.2013.11.015
• 发表时间: 2014-02
• 期刊: Journal of magnetic resonance
• 影响因子: 2.2
• 作者: Tony Reinsperger;B. Luy

Crosslinked poly(ethylene oxide) as a versatile alignment medium for the measurement of residual anisotropic NMR parameters.

• DOI: 10.1002/anie.201301929
• 发表时间: 2013-09
• 期刊: Angewandte Chemie
• 作者: Christian Merle;G. Kummerlöwe;J. Freudenberger;F. Halbach;W. Stöwer;Christoph Lierse v. Gostomski;J. Höpfner;T. Beskers;M. Wilhelm;B. Luy

Dipolare Restkopplungen als effektives Instrument der Konstitutionsanalyse: die unerwartete Bildung tricyclischer Verbindungen

• DOI: 10.1002/ange.201007305
• 发表时间: 2011-03
• 期刊: Angewandte Chemie
• 作者: Grit Kummerlöwe;B. Crone;M. Kretschmer;Stefan F. Kirsch;B. Luy

Direct prediction of residual dipolar couplings of small molecules in a stretched gel by stochastic molecular dynamics simulations

• DOI: 10.1002/mrc.4181
• 发表时间: 2015-03-01
• 期刊: MAGNETIC RESONANCE IN CHEMISTRY
• 影响因子: 2
• 作者: Frank, Andreas O.;Freudenberger, J. Christoph;Luy, Burkhard
• 通讯作者: Luy, Burkhard