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A 13C NMR study of pyridoxal-5′-phosphate oxime

✍ Scribed by Timo Korpela; Juhani Lundell; Eila Mäkinen


Publisher
John Wiley and Sons
Year
1979
Tongue
English
Weight
287 KB
Volume
12
Category
Article
ISSN
0749-1581

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✦ Synopsis


Abstract

Pyridoxal‐5′‐phosphate amino‐oxy acetate oxime was titrated in water, over the pH range 4–12, and the changes followed using ^13^C NMR. The results were compared to those of analogous Schiff's bases presented in the literature. The chemical shifts and titration curves of the oxime were appreciably different from those of the Schiff's bases, and the differences are explained as being due to the absence of ketoenamine‐enolimine tautomerism in the oxime. The low chemical shift value and the large changes of the oxime azomethine carbon during titration, as compared to the Schiff's bases, are discussed. The high stability of the oximes in water makes them suitable as model compounds for some tautomeric forms of the Iess stable Schiff's bases.


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