- Two dimensional NMR experiments use a sequence of two or more pulses with a variable time delay to generate spectra
- COSY spectra clarify where the protons are in a molecule
- Two and three dimensional NMR are used to solve protein structureS
Two dimensional NMR
Fig 1 The 1H-1H COSY spectrum of the amonio acid isoleucine
COSY for chemists
Fig 2 The 1H-nmr spectrum of isoleucine
Other two dimensional experiments
Fig 3 One dimensional 13C-nmr spectrum of isoleucine
Fig 4 13C-1H COSY spectrum of isoleucine with one dimensional 13C- and 1H-nmr spectra superimposed on horizontal and vertical axes respectively
Protein NMR spectroscopy in three dimensions
Fig 5 The 'backbone' of a protein from an NMR viewpoint (R = amino acid side chain)
Fig 6 a 3D-HNCO spectrum, which represents each of the H, N, and C atoms in a peptide linkage as an elipsoid in three dimensional space
© Reinhard Bunkel/sciencesoft.net
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5. K. Wüthrich, Angew. Chem. Int. Edn, 2003, 42, 3340.