A Simple and Easily Implemented Method for the Regioselective Introduction of Deuterium into Azolo[1,5-]pyrimidines Molecules.

A method for the technically easy-to-implement synthesis of deuterium-labeled pyrazolo[1,5-]pyrimidines and 1,2,4-triazolo[1,5-]pyrimidines have been developed. The regioselectivity of such transformations has been shown. H NMR and mass spectrometric methods have proved the quantitative nature of such transformations and the kinetics of deuterium exchange has been studied.