Identification and characterization of 2,5-dimethoxy-3,4-dimethyl-β-phenethylamine (2C-G)--a new designer drug

This study presents and discusses the mass spectrometric, infrared spectroscopic and nuclear magnetic resonance spectroscopic data of 2,5-dimethoxy-3,4-dimethyl-β-phenethylamine (2C-G), a new designer drug. A powder sample containing 2C-G was seized in Poland in 2011. The paper focuses on a comparison of the analytical features of 2C-G and other members of the 2C-series, in order to assess the possibility of unequivocal identification. The occurrence of intense peak at m/z = 178 and different intensities of the ions at m/z = 165 and 180 in the gas chromatography-electron impact-mass spectrometry (GC-EI/MS) spectrum of 2C-G made it possible to distinguish it from 2C-E. Differences in relative intensities of the ions at m/z = 192, 179 and 177 were observed for GC-EI/MS spectra of TFAA derivatives of 2C-G and 2C-E. An identical set of ions was recorded for these substances using the liquid chromatography-electrospray ionization/quadrupole time of flight mass spectrometry (LC-ESI/QTOFMS) method in both MS and tandem mass spectrometry (MS/MS) mode, but the distinction was possible based on differences in the ion intensities at m/z = 193.1223 and 178.0988. The Fourier transform infrared (FTIR) spectrum of 2C-G was significantly different from other members of the 2C-series, with a characteristic doublets at 993-1014 cm(-1) and 1099-1124 cm(-1) , and the ratio of bands at higher wavenumbers. Final elucidation of the structure of 2C-G was carried out by (1) H and (13) C NMR spectroscopy. The study indicated that the marketing of analogues of controlled substances poses a real analytical challenge for forensic laboratories, and the application of sophisticated methods is often required for unequivocal identification of a new substance.