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 13 C and 15 N 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- 13 C 2 ]-malonic ester (99% 13 C) was used as the 13 C isotope donor. The introduction of the 15 N atom was carried out using enriched sodium nitrite (98% 15 N). The obtained 13 C 2 and 15 N 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.