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NMR ¹H-Shielding Constants of Hydrogen-Bond Donor Reflect Manifestation of the Pauli Principle.

ABSTRACT: NMR spectroscopy is one of the most useful methods for detection and characterization of hydrogen bond (H-bond) interactions in biological systems. For H bonds X-H···Y, where X and Y are O or N, it is generally believed that a decrease in ¹H-shielding constants relates to a shortening of H-bond donor-acceptor distance. Here we investigated computationally the trend of ¹H-shielding constants for hydrogen-bonded protons in a series of guanine C8-substituted GC pair model compounds as a function of the molecular structure. Furthermore, the electron density distribution around the hydrogen atom was analyzed with the Voronoi deformation density (VDD) method. Our findings demonstrate that ¹H-shielding values of the hydrogen bond are determined by the depletion of charge around the hydrogen atom, which stems from the fact that electrons obey the Pauli exclusion principle.

SUBMITTER: Zarycz MNC

PROVIDER: S-EPMC6038099 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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NMR 1H-Shielding Constants of Hydrogen-Bond Donor Reflect Manifestation of the Pauli Principle.

Zarycz M Natalia C MNC Fonseca Guerra Célia C

The journal of physical chemistry letters 20180625 13

NMR spectroscopy is one of the most useful methods for detection and characterization of hydrogen bond (H-bond) interactions in biological systems. For H bonds X-H···Y, where X and Y are O or N, it is generally believed that a decrease in 1H-shielding constants relates to a shortening of H-bond donor-acceptor distance. Here we investigated computationally the trend of 1H-shielding constants for hydrogen-bonded protons in a series of guanine C8-substituted GC pair model comp ...[more]

PMID: 29927254

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