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Rotational spectrum and internal dynamics of the hydrogen-bonded pyrrole-pyridine aromatic pair.

ABSTRACT: Non-covalent interactions determine the three-dimensional structure and activity of biological molecules. In this work, the pyrrole-pyridine complex considered as a model of the NH⋯N hydrogen-bonded Watson-Crick base pairs has been generated in a supersonic expansion and characterized by chirped pulse Fourier transform microwave spectroscopy. The analysis of the unconventional spectral pattern of the 1:1 pyrrole-pyridine adduct and its ¹³C and ¹⁵N isotopologues reveal a non-planar complex, with a bent NH⋯N hydrogen bond and large amplitude motion of the pyrrole subunit. The bent structure is likely to arise from the stablishment of the secondary CH⋯N interaction between pyridine and pyrrole moieties.

SUBMITTER: Cabezas C

PROVIDER: S-EPMC7610520 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Rotational spectrum and internal dynamics of the hydrogen-bonded pyrrole-pyridine aromatic pair.

Cabezas Carlos C Peña Isabel I Caminati Walther W

Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy 20201215

Non-covalent interactions determine the three-dimensional structure and activity of biological molecules. In this work, the pyrrole-pyridine complex considered as a model of the NH⋯N hydrogen-bonded Watson-Crick base pairs has been generated in a supersonic expansion and characterized by chirped pulse Fourier transform microwave spectroscopy. The analysis of the unconventional spectral pattern of the 1:1 pyrrole-pyridine adduct and its <sup>13</sup>C and <sup>15</sup>N isotopologues reveal a non ...[more]

PMID: 33360563

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