2D-NMR spectral analysis

Nuzillard, J-M. and Emerenciano, V.D.P., Automatic structure elucidation through data base search and 2D NMR spectral analysis, Nat. Prod. Comms. 1, 57, 2006. 

The r3C NMR spectrum of (31) was very similar of that of (30), except for one oxygenated methylene in (31) and one oxygenated methine in (30).Further 2D NMR spectral analysis confirmed that (31) was 28-hydroxy-3-oxo-12-ursen-30-oic acid, Fig. (21). 

Detailed procedure involved in the analysis of chemical structure of polysaccharides by using ID- and 2D-NMR spectroscopic techniques is available in the literature [90,128-131]. The salient features of multidimensional NMR spectral analysis of polysaccharides are summarized here. 

The most popular ID and 2D pulse sequences together with the corresponding NMR raw data and spectra are supplied on CD-ROM. They are used to simulate NMR experiments, to exercise data processing and spectral analysis and serve as a data base for spectral interpretation. 

Karunaratne, D.N., Richards, J.C., Hancock, R.E.W. Characterization of lipid A from Pseudomonas aeruginosa O-antigenic B band lipopolysaccharide by ID and 2D NMR and mass spectral analysis. Arch Biochem Biophys 299 (1992) 368-376. 

In conclusion, what we have summarized in this article can be viewed as a very first step in the direction of a novel structural analysis method, which opens a vast new field of experimental research where much work remains to be done. Any 2D-IR spectroscopy certainly will be limited to molecular sizes smaller than are tractable by 2D NMR and x-ray spectroscopy because of the intrinsically poor spectral resolution of vibrational transitions. However, the one tremendous prospect that makes this research worthwhile is the inherent high time resolution of IR spectroscopy, which covers all biologically relevant time scales, starting from the subpicosecond time regime. The IR photon echo experiments have proven experimentally for the first time that the peptide backbone itself indeed fluctuates on these... 

Efforts focused on the automated analysis of 2D NMR spectra of complex metabolite mixtures are still somewhat limited. Considering the importance of peak alignment in 2D spectra, a statistical method was developed to align NMR peaks from the same metabolites across multiple 2D NMR spectra (120). A semiautomated method for metabolite identification from 2D TOCSY and HSQC spectra was also developed (103). The software tool, MetaboMiner, makes use of a spectral reference library extracted from publicly available databases to automatically match peaks and identify compounds. 

The CD-ROM enclosed with this book contains the special teaching version of the commercially available simulation program NMR-SIM and the NMR data processing programs ID WIN-NMR and 2D WIN-NMR. The versions of the WIN-NMR programs are the same as included with the books in this series Processing Strategies and Modern Spectral Analysis [1.10, 1.11]. 

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