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Applicability of vicinal heteronuclear (13C-1H, 15N-1H, 13C-15N) coupling constants for conformational analysis of amino acids: Phenylalanine, α-aminobutyric acid and β-alanine

✍ Scribed by Bozhana P. Mikhova; Mario F. Simeonov; Stefan L. Spassov

Publisher
John Wiley and Sons
Year
1985
Tongue
English
Weight
335 KB
Volume
23
Category
Article
ISSN
0749-1581

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✦ Synopsis

The vicinal "G'H, "N-'H and %-"N spin coupling constants were obtained from the 'H and =C NMR spectra of various ionic forms of the amino acids phenylalanine, a-aminobutyric acid and p-alanine, and also from their "N isotopomers. It is concluded that the "C-'H and =N-lH coupling constants are reliable parameters for conformational studies of amino acids, whereas the practical applicability of the %!-15N constants for the same purpose is doubtful.

' Close to the values in Refs 19-21. hThe estimated errors in fractional populations obtained on the basis of 3J(HH), 3J(CH), etc., are usually assumed to be a maximum of 10% (e.g. Ref. 5).

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