Abstract
The H-bonding interaction between the oxopurine base hypoxanthine and water is investigated using matrix-isolation FT-IR spectroscopy combined with theoretical density functional theory and ab initio methods. For vibrational frequency predictions, only the DFT/B3-LYP method is used, while for the prediction of relative energies and H-bond interaction energies of the complexes, four different theoretical methods are compared, i.e., RHF//RHF, MP2//RHF, DFT//DFT, and MP2//DFT. The oxo-N1HN7H, the oxo-N1HN9H, and the hydroxy-N9H (rotamer with the hydroxy-H atom pointed toward the N1 atom) are found to be the three most stable tautomeric forms of the free base. Different, stable complexes between these three tautomers and water have been predicted theoretically. The experimental FT-IR spectra agree well with this prediction, and most of the characteristic spectral data for the four most stable closed complexes, N7H···OH···OC6 and N1H···OH···OC6 of the O17 tautomer and N1H···OH···OC6 and N9H···OH···N3 of the O1...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.