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Conformational dependence of vicinal 13C′NCαH coupling constants in peptides: A dirac vector model investigation

✍ Scribed by P. Mohanakrishnan; K. R. K. Easwaran

Publisher: Wiley (John Wiley & Sons)
Year: 1979
Tongue: English
Weight: 308 KB
Volume: 18
Category: Article
ISSN: 0006-3525
DOI: 10.1002/bip.1979.360180714

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✦ Synopsis

Abstract

Theoretical calculations of the heteronuclear vicinal coupling constant ^3^J(^13^C′NC^α^H) in peptides have been carried out using the Dirac vector model. The results showed an angular dependence for this coupling constant, which can be expressed in the form ^3^J(^13^C′NC^α^H) = A cos^2^ θ + B cos θ + C, where A, B, and C are constants and θ is related to the torsional angle ϕ of the peptide backbone. The results of the present calculations are in very good agreement with those obtained using finite perturbation theory at the INDO level of approximation.

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