Identification of EA-3167, a Structural Analogue of the BZ Incapacitant, in Objects Delivered from the Zone of a Special Military Operation and Detection of Its Metabolites in Urine during Exposure of Rats

Earlier, we found that two alcohol-containing samples delivered from the zone of special military operation contain a rare psychoactive substance EA-3167, which is a structural analogue of the well-known incapacitant BZ, included in the Schedule 1 of the Chemical Weapons Convention. In addition to EA-3167, additives of methadone, α-pyrrolidinovalerophenone and tetrahydrocannabinol were found in liquids.
The aim of the work is to establish the analytical characteristics of EA-3167, as well as its metabolites in rat urine. Research methods. Structural identification of the detected substance by nuclear magnetic resonance, gas and liquid chromatomass spectrometry of delivered objects and rat urine obtained by exposing laboratory animals to the detected substance.
The results of the study. Concentrations of EA-3167 in liquids were found to be 910 and 3.9 μg/mL, respectively. It has been established that EA-3167 is subject to intensive metabolism in rats. More than 30 metabolites, representing products of mono- and dihydroxylation of aliphatic moieties of the molecule, ketone formation, and hydrolysis, have been tentatively identified in the urine of laboratory animals. Conclusion. The most convenient markers for confirming poisoning of EA-3167 by gas and liquid chromatography-mass spectrometry were the parent substance, the products of its monohydroxylation and the formation of carbonyl group on the cyclopentyl moiety.

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