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PubMed · 7433097

IR study of base stacking interactions.

A A Maevsky·B I Sukhorukov
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Abstract

For D2O solutions of 1,3-dimethyluracil, cytidine, caffeine, inosine and 2'-deoxyadenosine the concentration dependence of IR spectra (1800-1400 cm-1) have been found which reflects stacking association of these compounds. A method is proposed to use this data to obtain thermodynamic parameters of association and the molecular spectra in the monomer and associated forms. The homoassociation constant for 1,3-dimethyluracil was estimated as k=0.65. Stacking is shown to change radically the spectra, inducing a high-frequency shift of carbonyl vibrations and a decrease in the intensity of skeletal stretching vibration bands. This allows one to distinguish between the stacking interactions and hydrogen bonding. A conclusion is made about the considerable contribution of stacking interactions into the change of IR spectra of DNA and other polynucleotides following conformational transitions.

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CaffeineChemical PhenomenaChemistryMathematicsPurinesPyrimidinesSpectrophotometry, InfraredStructure-Activity RelationshipThermodynamicsJournal Article

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A A Maevsky, B I Sukhorukov. 1980-07-11. IR study of base stacking interactions.. https://doi.org/10.1093/nar%2F8.13.3029

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