Premium
Differentiation of methylbenzylpiperazines (MBPs) and benzoylpiperazine (BNZP) using GC‐MS and GC‐IRD
Author(s) -
AbdelHay Karim M.,
DeRuiter Jack,
Randall Clark C.
Publication year - 2012
Publication title -
drug testing and analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.065
H-Index - 54
eISSN - 1942-7611
pISSN - 1942-7603
DOI - 10.1002/dta.383
Subject(s) - chemistry , mass spectrum , isobaric process , mass spectrometry , structural isomer , fragmentation (computing) , isobaric labeling , mass , gas chromatography–mass spectrometry , ion , analytical chemistry (journal) , chromatography , amine gas treating , gas chromatography , stereochemistry , tandem mass spectrometry , organic chemistry , protein mass spectrometry , physics , computer science , thermodynamics , operating system
Three‐ring substituted methylbenzylpiperazines (MBPs) and their isobaric benzoylpiperazine (BNZP) have equal mass and many common mass spectral fragment ions. The mass spectrum of BNZP yields a unique benzoyl‐group containing fragment at m/z 122 and an additional major fragment at m/z 69 that allows its discrimination from the three MBP regioisomers. Perfluoroacylation of the secondary amine nitrogen of these isomeric piperazines gave mass spectra with differences in relative abundance of some fragment ions but acylation does not alter the fragmentation pathway and did not provide additional MS fragments of discrimination among these isomers. Gas chromatography coupled with infrared detection (GC‐IRD) provides direct confirmatory data for the structural differentiation between the four isomers. The mass spectra in combination with the vapour phase IR spectra provide for specific confirmation of each of the isomeric piperazines. The underivatized and perfluoroacyl derivatives of these four piperazines were resolved on a stationary phase of 100% trifluoropropyl methyl polysiloxane (Rtx‐200). Gas chromatography coupled with time‐of‐flight mass spectrometry provides an additional means of differentiating between the isobaric MBP and BNZP which have equivalent nominal masses but are different in their elemental composition and exact masses. Copyright © 2012 John Wiley & Sons, Ltd.