Development of a new isochromenylium-based derivatizing reagent for the analysis of α-amino acids and related compounds by LC-MS

A new pyrylium salt, 3,6,7-trimethoxyisochromenylium tetrafluoroborate (TriMIC), was developed for the derivatization of α-amino acids and other compounds with an NH2 group for use in LC-MS analysis. TriMIC was prepared using routine synthetic procedures from inexpensive raw materials. It has high reactivity, and derivatization of α-amino acids occurs under mild reaction conditions in an acetonitrile-methanol mixture. The efficiency of amino acid derivatization was evaluated using 10 amino acids.