Mass Spectral and Chromatographic Studies on a Series of Regioisomers and Isobaric Derivatives Related To Methylenedioxymethamphetamines

The drug MDMA (3,4-methylenedioxymethamphetamine) has regioisomeric and isobaric substances of mass equivalence, which have similar analytical properties which can lead to misidentification. In this study, the direct and indirect regioisomers of MDMA and also isobaric substances related to MDMA were synthesized and compared to MDMA by using gas chromatographic and spectrometric techniques. Results of the analysis indicate that the direct regioisomers and isobaric substances of MDMA can not be easily differentiated by mass spectrometry or ultraviolet (UV) spectrophotometry. The synthesized compounds were converted to their perfluoroacyl derivatives in an effort to individualize their mass spectra and to improve chromatographic resolution. The study found that derivatized MDMA was easily distinguished from its derivatized direct and indirect regioisomers using mass spectrometry. In addition, unique fragment ions were observed for the various direct regioisomeric side chains and the methoxymethcathinones.