The application of 15N-NMR spectroscopy in the problems of nucleoside and nucleotide chemistry.

15N-NMR spectroscopy has been shown to be useful to understand the chemical nature of nitrogen in a biomolecule. We herein report the use of 15N-NMR as a tool for the study of exact location of a substitution on the guanine or uracil moieties in a nucleoside, to understand the implication of a protecting group on the reactivity and the basicity of nitrogen atoms in pyrimidines or in purines and to assign the structure of isomeric N7 and N9 substituted purines.