Stable Isotope-Labeled Azoloazines. Synthesis of a 13С and 15N Isotope-Enriched Derivative of Pyrazolo[5,1-c][1,2,4]Triazine –potential Antidiabetic Agent

A simple and selective method for introducing stable 13C and 15N isotopes into the structure of the sodium salt of 4-oxo-1,4-dihydropyrazolo[5,1-c][1,2,4]triazine-3,8-dicarboxylic acid diethyl ester, a potential antiglycation agent, has been developed. Labeled [1,3-13C2]-malonic ester (99% 13C) was used as the 13C isotope donor. The introduction of the 15N atom was carried out using enriched sodium nitrite (98% 15N). The obtained 13C2 and 15N isotope-labeled analog of a promising antidiabetic compound of the pyrazolo- [5,1-c][1,2,4]triazine series was characterized by NMR spectroscopy and high-resolution mass spectrometry.