Structural characterization and differentiation of isomeric omega-bromoalkoxy derivatives of (E)-chalcone by means of mass spectrometry

Mass spectrometry with electron ionization and electrospray ionization have been applied to characterize and differentiate the isomeric ortho-, meta- or para-(E)-bromoalkyloxychalcones 1-15. The difference in the values of micro1-micro5 (i.e. the ratio of abundances of the selected fragment ions to those of the molecular ions) in the series of isomeric chalcones studied and the so-called "in-source" fragmentation induced by increasing cone voltage have been found to be important and reliable indicators differentiating the isomers studied.