Nitrogen-15 NMR spectroscopy of N-metallated nucleic acids: insights into 15N NMR parameters and N–metal bonds

Abstract

It was recently demonstrated spectroscopically that RNA/DNA nucleobases can bind to metal cations in aqueous solution through coordination bonds and covalent bonds. Nitrogen-15 (¹⁵N) NMR spectroscopy was employed and shown to be a powerful tool for determining the mode of metal ion binding to nitrogen atoms in RNA/DNA molecules. This review describes ¹⁵N NMR spectroscopic characteristics in accordance with the mode of metal ion binding to nitrogen atoms. The general rules for ¹⁵N chemical shift changes, which are applicable to the determination of the metal ion binding mode of N-metallated compounds, are also described.