GC-MS studies on side chain regioisomers related to substituted methylenedioxyphenethylamines: MDEA, MDMMA, and MBDB.
Tamer Awad, Tarek Belal, Hadir M Maher, Jack DeRuiter, C Randall Clark
Journal of Chromatographic Science October 1, 2010 DOI: 10.1093/chromsci/48.9.726 (opens in new tab) via PubMed
Summary
AI-generated from the abstractThree drugs of abuse—MDEA, MDMMA, and MBDB—and seven additional side chain regioisomers share the same molecular weight (207) and major mass spectral fragments (m/z 72 and 135/136), making them difficult to distinguish by routine mass spectrometry. The authors evaluated trifluoroacetyl, pentafluoropropionyl, and heptafluorobutryl derivatives of the primary and secondary amines using gas chromatography-mass spectrometry. These derivatives produced significantly individualized mass spectra with unique fragment ions that allowed specific side chain identification. Trifluoroacetyl and heptafluorobutryl derivatives provided the most specific ions for distinguishing the compounds, and all perfluoroacyl derivatives showed reasonable resolution on the polar Rtx-200 stationary phase.
Study at a glance
| Characteristics | Method development and validation study Peer reviewed |
|---|---|
| Population | Three controlled drug substances (MDEA, MDMMA, MBDB) and seven additional side chain regioisomers |
| Key finding | Perfluoroacyl derivatives, especially trifluoroacetyl and heptafluorobutryl, produce unique fragment ions that allow specific identification of side chain regioisomers of 3,4-methylenedioxyphenethylamines that are otherwise indistinguishable by mass spectrometry. |
Abstract
Three regioisomeric 3,4-methylenedioxyphenethylamines having the same molecular weight and major mass spectral fragments of equal mass have been reported as drugs of abuse in forensic studies in recent years. These compounds are 3,4-methylenedioxy-N-ethylamphetamine (MDEA), 3,4-methylenedioxy-N,N-dimethylamphetamine (MDMMA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB). A series of seven additional side chain regioisomers have mass spectra essentially equivalent to the three controlled drug substances, all have molecular weight of 207 and major fragment ions in their electron ionization mass spectra at m/z 72 and 135/136. The trifluoroacetyl, pentafluoropropionyl, and heptafluorobutryl derivatives of the primary and secondary regioisomeric amines were evaluated in GC-MS studies. The mass spectra for these derivatives were significantly individualized, and the resulting unique fragment ions allowed for specific side chain identification. The trifluoroacetyl and heptafluorobutryl derivatives provided more specific fragment ions for molecular individualization among these regioisomeric substances. These perfluoroacyl derivatives showed reasonable resolution on the polar stationary phase Rtx-200.