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Updated: Apr 25, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Conformational isomerism of pyridoxal. Infrared matrix isolation and theoretical studies
1Faculty of Chemistry, University of Wrocław, Joliot-Curie 14, 50-383 Wrocław, Poland.
Abstract:
A combined matrix isolation FTIR and theoretical DFT/B3LYP/6-311++G(2p,2d) study of pyridoxal was performed. The calculations resulted in five stable PLHB conformers stabilized by intramolecular O-H⋯O bonding between phenolic OH and carbonyl C=O groups and another thirteen conformers in which OH or/and aldehyde groups are rotated by 180° around CO or/and CC bonds leading, respectively, to formation of PLO, PLA and PLOA conformers. The analysis of the spectra of the as-deposited matrix indicated that two most stable PLHB1 and PLHB2 conformers with intramolecular hydrogen bond are present in the matrix. The exposure of the PL/Ar matrix to mercury lamp radiation (λ>345 nm) induced conformational change of PLHB isomers to PLOA ones.
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