Synthesis and Characterization of Deuterated Glycine d-5: comparison of deuterated and non-deuterated glycine spectra

Recent developments particularly in the field of nuclear magnetic resonance spectrometry suggest that there is a growing demand for compounds labelled with stable isotopes [1]. Deuterium is one of two stable isotopes of hydrogen, can be used as a labeling agent to distinguish a molecule from its protonated analogues and, the kinetic isotope effect, which deuterium exhibits by virtue of its increased bonding strength, permits a more detailed study of specific mechanisms of amino acid reactions.In this study, the synthesis of deuterium-labelled [2H5]-glycine is described. The isotopically labelled compounds are applied as internal standards in liquid chromatography–mass spectrometry (LC–MS) assays and enzyme activity determination. Comparison of its spectrum with that of ordinary glycine exhibited the significant differences in the FT-IR and NMR spectra. A convenient method for the synthesis of glycine has been elaborated [Fig. 1]. Deuteration with high isotopic purity (%D ≥ 98) followed by reaction of the 2-ethylacetamidomalonate with D2O/DCl 20% gave deuteroglycine-d6(I) salt. Conversion of this salt to the neutral glycine-d5(II) was performed using addition of trimethylamine [2].