Mass spectrometric investigation of 2-aminopropiophenones and some of their metabolites.

Complex metabolic mixtures of 2-aminopropiophenones, obtained both after in vitro and human in vivo metabolism of these compounds, have been investigated using both mass spectrometry and gas chromatography/mass spectrometry. The mass spectrometric fragmentation schemes of the compounds have been proposed and verified. The schemes are based on the characteristic fragments obtained by alpha-cleavage of these compounds using direct inlet mass spectrometry or gas chromatography/mass spectrometry. These findings were confirmed with chemical ionization mass spectrometry, when quasi-molecular (MH+) ions were obtained as the highest relative abundance ions for all the compounds investigated, and were used in metabolic investigations of 2-aminopropiophenones.