Synthesis of (~(15)N_3)melamine and (~(13)C_3)cyanuric acid

摘要

This report presents an efficient syntheses of two labelled internal standards [~(15)N_3]melamine and [~(13)C_3]cyanuric acid with the common substrates [~(15)N]NH_4Cl and [~(13)C]urea, respectively. Both standards with excellent isotopic and chemical purities were prepared in good yields and could be used as internal standards without further purification. An increased incidents of kidney stones and renal failure reported in China and the large outbreak of renal diseases and deaths of pet animals in USA are believed to be associated with melamine-contaminated dairy products and pet foods in which melamine has been deliberately added to boost its apparent protein content. Melamine combines with cyanuric acid to form melamine cyanurate crystal sediment which obstructed and damaged renal tubules, leading to renal failure. Liquid chromatography isotope diluted tandem mass spectrometry (LC-IDMS/MS) methods have proved sensitive and reliable for the determination of both melamine and cyanuric acid among various analytical approaches.