Ornithine is an amino acid of which the side chain contains three pairs of diastereotopic protons. The diastereotopic protons are chemically nonequivalent. The NOEDIF spectra of ornithine were obtained in an acid solution to assign the individual chemical shifts of the β diastereotopic protons with the aid of the theoretical calculation of conformation distribution. The β Pro-S resonance was found to be at a higher field than β pro-R proton.
(S,S)-Ethylenediamine-N,N'-disuccinic acid (EDDS) was found to be a good chiral chemical shift reagent ligand in water solution. The Ytterbium complex of EDDS was used to distinguish L-ornithine and D-ornithine. For the α protons, the enantiomeric shift difference was affected by the pH of the solution and the substrate : Yb(EDDS)’ ratio. The association constants between Yb(EDDS)’ and L- or D-ornithine were found to be slightly different. Yb(EDDS)’ may also be useful to distinguish between the diastereotopic protons in ornithine and other molecules in NMR spectra.
| Identifer | oai:union.ndltd.org:pacific.edu/oai:scholarlycommons.pacific.edu:uop_etds-3321 |
| Date | 01 January 1997 |
| Creators | Zhao, Jianzhou |
| Publisher | Scholarly Commons |
| Source Sets | University of the Pacific |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | University of the Pacific Theses and Dissertations |
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