Electron Ionization Mass Spectrometric Study of Some Substituted 1,3-oxazoles

Abstract

Heterocyclic compounds are widely used as pharmaceuticals. Tacrine (THA) was the first drug approved for the treatment of Alzheimer’s disease (AD) and a great effort has been made to design and synthesize new THA-analogues in order to evaluate their beneficial effects as therapeutic agents in this disease.1-6 Contrasting with the pharmaceutical interest, mass spectrometric studies of these compounds and of some of its precursors, namely the oxazole and oxazole derivatives, are scarce. In order to obtain its structural information, a mass spectrometric study was performed with some 5-amino-2-aryl-4-cyano-1,3-oxazoles (Compounds 1 - 5) using a quadrupole mass spectrometer, equipped with an electron ionization (EI) ion source. Detailed fragmentation pathways have been established for all significant ions, including some fragment ions characteristic of the oxazole family.

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