title: Differentiation of ring-substituted bromoamphetamine analogs by gas chromatography-tandem mass spectrometry.
abstract: There has been a rapid increase over the last decade in the appearance of new non-controlled psychoactive substances. Minor changes in the chemical structures of these compounds, such as the extension of an alkyl residue or replacement of a single substituent, are regularly made to avoid regulatory control, leading to the manufacture of many new potentially dangerous drugs. Bromoamphetamine analogs (bromoamphetamine [Br-AP] and bromomethamphetamine (Br-MA]) are ring-substituted amphetamines that can behave as stimulants, as well as exhibiting inhibitory activity towards monoamine oxidases in the same way as amphetamines. Gas chromatography-tandem mass spectrometry (GC-MS-MS) was used in this study to differentiate ring-substituted bromoamphetamine analogs. Free bases, trifluoroacetyl derivatives, and trimethylsilyl (TMS) derivatives of six analytes were successfully separated using DB-1ms and DB-5ms columns. Electron ionization MS-MS analysis of the TMS derivatives allowed for the differentiation of three regioisomers. TMS derivatives of 2-positional isomers provided significant product ions. The spectral patterns of 3- and 4-positional isomers were different. Chemical ionization MS-MS analysis of free bases for [M+H-HBr]+ions atm/z134 and 148 allowed for differentiation of the regioisomers. The spectra of 2-positional isomers contained characteristic product ions formed by dehydrogenation atm/z132 andm/z146 for 2Br-AP and 2Br-MA, respectively. The spectra of 3-positional isomers contained α-cleaved iminium cations as the base peaks. The spectra of 4-positional isomers showed a tropylium cation atm/z91 as the base peak. These results demonstrate that GC-MS-MS can be used for the differentiation of regioisomeric Br-AP analogs in forensic practice.
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inoue
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan ; Technopro, Inc. Technopro R&D, Company, 1-15-1 Benten, Chuo-ku, Chiba, 260-0045 Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Negishi
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan ; Technopro, Inc. Technopro R&D, Company, 1-15-1 Benten, Chuo-ku, Chiba, 260-0045 Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nakazono
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan.
authors.forename: Yuko T
authors.initials: YT
authors.lastname: Iwata
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Tsujikawa
authors.affiliation: National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, 277-0882 Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ohtsuru
authors.affiliation: Technopro, Inc. Technopro R&D, Company, 1-15-1 Benten, Chuo-ku, Chiba, 260-0045 Japan ; Biochemical Toxicology Laboratory, Faculty of Pharmaceutical Sciences, Kobegakuin University, 1-1-3 Minatojima, Chuo-ku, Kobe, 650-8586 Japan.
authors.forename: Kazuna
authors.initials: K
authors.lastname: Miyamoto
authors.affiliation: Biochemical Toxicology Laboratory, Faculty of Pharmaceutical Sciences, Kobegakuin University, 1-1-3 Minatojima, Chuo-ku, Kobe, 650-8586 Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Biochemical Toxicology Laboratory, Faculty of Pharmaceutical Sciences, Kobegakuin University, 1-1-3 Minatojima, Chuo-ku, Kobe, 650-8586 Japan.
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Kasuya
keywords: Bromoamphetamine analogs; Chemical ionization; Electron ionization; GC–MS-MS; Regioisomeric differentiation