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Favipiravir-Tautomeric and Complexation Properties in Solution.

ABSTRACT: The tautomeric properties of favipiravir were investigated experimentally for the first time by using molecular spectroscopy (UV-Vis absorption, fluorescence and NMR), as well as DFT quantum-chemical calculations. According to the obtained results, the enol tautomer is substantially more stable in most of the organic solvents. In the presence of water, a keto form appears to be favored due to the specific solute-solvent interactions. Upon the addition of alkaline-earth-metal ions, deprotonation and complexation occurred simultaneously, giving the formation of 2 : 1 ligand : metal complexes. According to the theoretical simulations, the metal ion is captured between the carbonyl groups as a result of the size-fit effect.

SUBMITTER: Deneva V

PROVIDER: S-EPMC9864296 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Favipiravir-Tautomeric and Complexation Properties in Solution.

Deneva Vera V Slavova Sofia S Kumanova Alina A Vassilev Nikolay N Nedeltcheva-Antonova Daniela D Antonov Luidmil L

Pharmaceuticals (Basel, Switzerland) 20221228 1

The tautomeric properties of favipiravir were investigated experimentally for the first time by using molecular spectroscopy (UV-Vis absorption, fluorescence and NMR), as well as DFT quantum-chemical calculations. According to the obtained results, the enol tautomer is substantially more stable in most of the organic solvents. In the presence of water, a keto form appears to be favored due to the specific solute-solvent interactions. Upon the addition of alkaline-earth-metal ions, deprotonation ...[more]

PMID: 36678542

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