The effect of stereochemistry on sodium ion complexation in nucleoside-metallacarborane conjugates
Agnieszka B Olejniczak1, Jan Milecki, Grzegorz Schroeder
1Laboratory of Molecular Virology and Biological Chemistry, Institute for Medical Biology of the Polish Academy of Sciences, Lodowa 106, 93-232 Łódź, Poland.
Abstract:
CONJUGATES OF PURINE AND PYRIMIDINE NUCLEOSIDES: thymidine and 2'-deoxyguanosine with cobalt-metallacarborane were studied for their sodium ion complexing properties. Formation of stable complexes of 1 : 1 stoichiometry was proved by ESI MS spectroscopy and (23)Na NMR. Equilibrium constants and energies of complex formation were calculated. Complexation of alkali-metals by nucleoside-metallacarborane conjugates may affect the physicochemical and biological properties of the conjugates and should be taken into consideration during biological evaluation of these types of modifications.
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