Structure Confirmation of Three New Psychoactive Substances and Qualitative Identification of Unknown Substances.

Objectives: To establish the structural confirmation methods of three suspected new psychoactive substances (NPSs), and explore a more general qualitative testing method.

Methods: Infrared absorption spectroscopy (IR), gas chromatography-mass spectrometry (GC-MS), ¹H-nuclear magnetic resonance spectroscopy (¹H-NMR), ¹³C-nuclear magnetic resonance spectroscopy (¹³C-NMR), ¹⁹F-nuclear magnetic resonance spectroscopy (¹⁹F-NMR) and other techniques were used to identify the composition and structure of 5 samples containing suspected NPS submitted by public security bureaus.

Results: NPSs were found in the above 5 samples, and 3 were confirmed as NPS included in the newly listed controlled substances on July 1, 2024, namely 2-(methylamino)-2-(2-methylphenyl)cyclohexan-1-one (2-MDCK), 2-(ethylamino)-2-(2-fluorophenyl)cyclohexan-l-one (2-FXE), 1-(3,4-methylenedioxyphenyl)-2-(dimethylamino)pentan-1-one (dipentylone), respectively. The first two substances were phencyclidine NPS, and the third substance was synthetic cathinone NPS.

Conclusions: This study systematically summarizes the distinguishing features of the infrared absorption spectrometry, nuclear magnetic resonance spectroscopy and mass spectrometry of three NPSs, which can provide a reference for the qualitative identification of unknown substances.