Interaction of Pd2 + complexes of 2,6-disubstituted pyridines with nucleoside 5′-monophosphates

To learn more about the underlying principles of metal-ion-mediated recognition of nucleic acid bases, PdCl+ complexes of six 2,6-disubstituted pyridines, viz. pyridine-2,6-dicarboxamide, its N2,N6-dimethyl and N2,N6-diisopropyl derivatives, 6-carbamoylpyridine-2-carboxylic acid, 6-aminomethylpyridine-2-carboxamide and its N2-methyl derivative, were prepared and their interaction with nucleoside 5′-monophosphate (NMP) was studied by 1H NMR spectroscopy in D2O at pH 7.2. The binding sites within the nucleobases were assigned on the basis of Pd2 + induced changes in chemical shifts of the base moiety proton resonances. The mole fractions of NMPs engaged in mono- or dinuclear Pd2 + complexes were determined at various concentrations by comparing the intensities of the aromatic and anomeric protons of the complexed and uncomplexed NMPs. Some of the pyridine complexes showed moderate discrimination between the NMPs.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideSynopsisTo learn more about the underlying principles of metal-ion-mediated recognition of nucleic acid bases, PdCl+ complexes of six 2,6-disubstituted pyridines were prepared and their interaction with nucleoside 5′-monophosphate (NMP) was studied by 1H NMR spectroscopy in D2O at pH 7.2.