School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
Org Biomol Chem. 2011 Oct 21;9(20):7062-4. doi: 10.1039/c1ob06097j. Epub 2011 Aug 26.
High resolution diffusion-ordered NMR spectroscopy allows the separation of signals from different species based on their diffusion coefficients. In general this requires that the NMR spectra of the components do not have overlapping signals, and that the diffusion coefficients are significantly different. Modifying the solvent matrix in which a sample is dissolved can change the diffusion coefficients observed, allowing resolution ("matrix-assisted DOSY"). We show here that dissolving the two naturally-occurring epimers of naringin in an aqueous solution of β-cyclodextrin causes both shift and diffusion changes, allowing the signals of the epimers to be distinguished. Chiral matrix-assisted DOSY has the potential to allow simple resolution and assignment of the spectra of epimers and enantiomers, without the need for derivatisation or for titration with a shift reagent.
高分辨率扩散排序核磁共振波谱（High resolution diffusion-ordered NMR spectroscopy）允许根据扩散系数将来自不同物种的信号分离。通常，这要求各成分的核磁共振波谱没有重叠信号，且扩散系数显著不同。通过改变样品溶解的溶剂基质，可以改变观察到的扩散系数，从而实现分辨率（“基质辅助扩散排序”）。我们在此展示，将柚皮苷的两种天然差向异构体溶解在β-环糊精的水溶液中，会引起位移和扩散变化，从而可以区分差向异构体的信号。手性基质辅助扩散排序有可能在无需衍生化或用位移试剂滴定的情况下，允许简单地分辨和分配差向异构体和对映异构体的光谱。
