Structure Analysis and Characterization of Aminorex Analogue 4'-F-4-MAR.
10.12116/j.issn.1004-5619.2020.05.013
- Author:
Cui Mei LIU
1
;
Zhen Dong HUA
1
;
Wei JIA
1
Author Information
1. Key Laboratory of Drug Monitoring and Control, Ministry of Public Security, People's Republic of China, Drug Intelligence and Forensic Center of the Ministry of Public Security, Beijing 100193, China.
- Publication Type:Journal Article
- Keywords:
forensic toxicology;
new psychoactive substance;
gas chromatography-mass spectrometry;
spectroscopy, Fourier transform infrared;
nuclear magnetic resonance;
aminorex;
4’-F-4-methylaminorex （4’-F-4-MAR）
- MeSH:
Aminorex;
Chromatography, High Pressure Liquid;
Gas Chromatography-Mass Spectrometry;
Mass Spectrometry;
Nitroimidazoles;
Spectrometry, Mass, Electrospray Ionization
- From:
Journal of Forensic Medicine
2020;36(5):677-681
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the identification method for 4'-F-4-methylaminorex （4'-F-4-MAR） in samples without reference substance. Methods Gas chromatography-mass spectrometry （GC-MS）, ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry （UPLC-QTOF-MS）, nuclear magnetic resonance （NMR） and Fourier transform infrared （FTIR） were comprehensively used for the structure identification of 4'-F-4-MAR in samples. Results Under the positive electrospray ionization （ESI+） mode, quasi-molecular ion in the first order mass spectrometry of the unknown compound was 195.092 6 and its molecular formula was inferred to be C10H11FN2O. The fragment ions in the mass spectrometry of the unknown compound were compared with the related fragment ions of 4,4'-dimethylaminorex （4,4'-DMAR） in literature. It was found that the main fragment ions of the unknown compound were all 4 bigger than the corresponding fragment ions of 4,4'-DMAR. Therefore, the unknown compound was inferred to be a 4,4'-DMAR analogue with a methyl substituted by a fluorine in the benzene ring. The equivalent protons at δ=7.30 and δ=7.06 in 1H-nuclear magnetic resonance （1H-NMR） spectra and the characteristic spin-spin coupling constants （1JC-F=245.2 Hz, 2JC-F=21.3 Hz, 3JC-F=8.1 Hz） for 13C-19F interactions in carbon spectra, further proved that the fluorine substituted methyl at the para-position of the benzene ring. Finally, the unknown compound was determined as 4'-F-4-MAR. Conclusion A method that comprehensively used the identification materials 4'-F-4-MAR in GC-MS, UPLC-QTOF-MS, NMR and FTIR is established and the fragmentation mechanism of fragmentation ions of 4'-F-4-MAR created under the two modes -- electron impact （EI） and electrospray ionization under collision induced dissociation （ESI-CID） is deduced. The information will assist forensic science laboratories in identifying this compound or other substances with similar structure in their case work.
