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

ATR-FTIR combined with machine learning for the fast non-targeted screening of new psychoactive substances

Due to the diversity and fast evolution of new psychoactive substances (NPS), both public health and safety are threatened around the world. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), which serves as a simple and rapid technique for targeted NPS screening, is challenging with the rapid structural modifications of NPS. To achieve the fast non-targeted screening of NPS, six machine learning (ML) models were constructed to classify eight categories of NPS, including synthetic cannabinoids, synthetic cathinones, phenethylamines, fentanyl analogues, tryptamines, phencyclidine types, benzodiazepines, and "other substances" based on the 1099 IR spectra data items of 362 types of NPS collected by one desktop ATR-FTIR and two portable FTIR spectrometers. All these six ML classification models, including k-nearest neighbor (KNN), support vector machine (SVM), random forest (RF), extra trees (ET), voting, and artificial neural networks (ANNs) were trained through cross validation, and f1-scores of 0.87-1.00 were achieved. In addition, hierarchical cluster analysis (HCA) was performed on 100 synthetic cannabinoids with the most complex structural variation to investigate the structure-spectral property relationship, which leads to a summary of eight synthetic cannabinoid sub-categories with different "linked groups". ML models were also constructed to classify eight synthetic cannabinoid sub-categories. For the first time, this study developed six ML models, which were suitable for both desktop and portable spectrometers, to classify eight categories of NPS and eight synthetic cannabinoids sub-categories. These models can be applied for the fast, accurate, cost-effective, and on-site non-targeted screening of newly emerging NPS with no reference data available.

Identification of seven psychedelic 2,5-dimethoxy-phenylethyl-amine-based designer drugs via benchtop 1 H nuclear magnetic resonance spectroscopy

The dissemination of spectral information of new psychoactive substances (NPS) acquired on benchtop nuclear magnetic resonance (NMR) spectrometers is of high importance considering the emerging application of such portable and accessible instruments in forensic analyses. Seven members of the 2C-X series (2C-B, 2C-C, 2C-D, 2C-E, 2C-P, 2C-T2, and 2C-T7) of NPS were analyzed via 60 MHz ¹ H benchtop NMR spectroscopy and their molecular structural relations are discussed with respect to the observed proton NMR spectra.

Spectral trends in GC-EI-MS data obtained from the SWGDRUG mass spectral library and literature: A resource for the identification of unknown compounds

Rapid identification of new or emerging psychoactive substances remains a critical challenge in forensic drug chemistry laboratories. Current analytical protocols are well-designed for confirmation of known substances yet struggle when new compounds are encountered. Many laboratories initially attempt to classify new compounds using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS). Though there is a large body of research focused on the analysis of illicit substances with GC-EI-MS, there is little high-level discussion of mass spectral trends for different classes of drugs. This manuscript compiles literature information and performs simple exploratory analyses on evaluated GC-EI-MS data to investigate mass spectral trends for illicit substance classes. Additionally, this work offers other important aspects: brief discussions of how each class of drugs is used; illustrations of EI mass spectra with proposed structures of commonly observed ions; and summaries of mass spectral trends that can help an analyst classify new illicit compounds.

Identification of new NBOH drugs in seized blotter papers: 25B-NBOH, 25C-NBOH, and 25E-NBOH

Purpose

The recreational drug market remains dynamic. After the introduction of 25I-NBOH, an N-benzylphenethylamine and new psychoactive substance, as option for LSD and NBOMe drugs, new NBOH substances have been identified in recent years. Herein, we report our efforts for the identification and structural elucidation of three new NBOHs detected in seized blotter papers: 25B-NBOH, 25C-NBOH, and 25E-NBOH.

Methods

Blotter papers seized between 2017 and 2018 by local police force in Brazil were submitted to extraction, purification, identification and characterization using attenuated total reflectance-Fourier transform infrared spectroscopy, gas chromatography—mass spectrometry, liquid chromatography—tandem mass spectrometry, and one- and two-dimensional nuclear magnetic resonance spectroscopy.

Results

Three new NBOHs were characterized: 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol (25E-NBOH, 2C-E-NBOH), 2-(((4-chloro-2,5-dimethoxyphenethyl)amino)methyl)phenol (25C-NBOH, 2C-C-NBOH), and 2-(((4-bromo-2,5-dimethoxyphenethyl)amino)methyl)phenol (25B-NBOH, 2C-B-NBOH).

Conclusions

To our knowledge, this is the first report for identification and detailed characterization of 25B-NBOH, 25C-NBOH, and 25E-NBOH in seized samples. NBOH substances are not under United Nations Conventions control. The identification of seized blotter papers between 2014 and beginning of 2019 showed that NBOH substances have become the main hallucinogenic drug in the region. These group are thermolabile under gas chromatographic conditions, demanding other analytical approaches of analysis to avoid misidentifications. Unfortunately, the knowledge about toxicology of NBOHs are limited.

Mass spectrometric properties of N-(2-methoxybenzyl)-2-(2,4,6-trimethoxyphenyl)ethanamine (2,4,6-TMPEA-NBOMe), a new representative of designer drugs of NBOMe series and derivatives thereof

Emergence of new psychoactive substances, hallucinogenic phenethylamines in particular, in illicit market is a serious threat to human health in global scale. We have detected and identified N-(2-methoxybenzyl)-2-(2,4,6-trimethoxyphenyl)ethanamine (2,4,6-TMPEA-NBOMe), a new compound in NBOMe series. Identification was achieved by means of gas chromatography/mass spectrometry (GC/MS), including high-resolution mass spectrometry with tandem experiments (GC/HRMS and GC/HRMS² ), ultra-high performance liquid chromatography/high-resolution mass spectrometry with tandem experiments (UHPLC/HRMS and UHPLC/HRMS² ), and ¹ H and ¹³ C nuclear magnetic resonance spectroscopy. The peculiarities of fragmentation of the compound under electron ionization (EI) and collision-induced dissociation were studied. Despite of the empirical rule denying migration of the hydrogen atom in McLafferty rearrangement to the benzene ring with substituents in the both ortho-positions, it easily occurs for 2,4,6-TMPEA-NBOMe in EI conditions. We have noticed that electron-donating substituents, e.g. methoxy groups in the both ortho-positions and para-positions favor the rearrangement. For specially synthesized N-methyl and N-acyl derivatives McLafferty rearrangement is not observed. N-Acyl derivatives demonstrate McLafferty rearrangement, but the charge retains at the alternative fragment involving N-acyl carbonyl group. We have also showed that the hydrogen atoms in 2,4,6-trimethoxybenzene ring may be easily substituted for deuterium or for strong electrophiles like trifluoroacetyl. Analytical characteristics of 2,4,6-TMPEA-NBOMe and of some derivatives thereof which enable their determination in various criminal seizures are given. Copyright © 2016 John Wiley & Sons, Ltd.

Structural elucidation and identification of a new derivative of phenethylamine using quadrupole time-of-flight mass spectrometry

RATIONALE

In recent years, the phenomenon of uncontrolled distribution of new psychoactive substances that were marketed without prior toxicological studies has been observed. Because many designer drugs are related in chemical structure, the potential for misidentifying them is an important problem. It is therefore essential to develop an analytical procedure for unequivocal elucidation of the structures of these compounds. The issue has been discussed in the context of 25I-NBMD [2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2,3-methylenedioxyphenyl)methyl]ethanamine], a psychoactive substance first discovered on the drug market in 2012.

METHODS

The substance was extracted from blotter papers with methanol. Separation was achieved via liquid chromatography. Analysis was conducted by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOFMS). Identification of the psychoactive component was supported by electron impact gas chromatography/mass spectrometry (GC/EI-MS).

RESULTS

The high accuracy of the LC/ESI-QTOFMS method allowed the molecular mass of the investigated substance (M(exp) = 441.0438 Da; mass error, ∆m = 0.2 ppm) and the formulae of ions formed during fragmentation to be determined. The main ions were recorded at m/z = 135.0440, 290.9876 and 305.9981. Structures of the obtained ions were elucidated in the tandem mass spectrometry (MS/MS) experiments by comparing them to mass spectra of previously detected derivatives of phenethylamine.

CONCLUSIONS

The performed study indicated the potential for using LC/QTOFMS method to identify new designer drugs. This technique can be used supplementary to standard GC/MS. Prior knowledge of the fragmentation mechanisms of phenethylamines allowed to predict the mass spectra of the novel substance--25I-NBMD.

High-performance liquid chromatography tandem mass spectrometry method for the determination of 2CC-NBOMe and 25I-NBOMe in human serum

2CC-NBOMe {4-chloro-2,5-dimethoxyphenethyl-N-[(2-methoxyphenyl) methyl] ethanamine} and 25I-NBOMe {2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl) methyl] ethanamine} are of a class of N-benzyl phenethylamine derivatives whose synthesis was first reported in the scientific literature in 2011. Recent reports from 'personal drug experience websites' and in the popular press indicate these drugs are the latest in a series of designer 'Bath Salt' drugs of abuse. The presented high-performance liquid chromatography triple quadrupole mass spectrometry (HPLC/MS/MS) method was developed for the detection and quantification of 2CC-NBOMe and 25I-NBOMe in serum of intoxicated emergency department patients. The assay applies 2-​(2,​5-​dimethoxyphenyl)-​N-​(2-​methoxybenzyl) ethanamine (25H-NBOMe) as the internal standard. Samples were extracted using solid-phase extraction columns. The chromatographic separation was performed on a Luna 3 µ C8(2) 100 Å, 100 × 2.0 mm, column. Detection was accomplished by multiple-reaction monitoring via an electrospray ionization source operating in the positive ionization mode. The calibration curves were linear over the investigated concentration range, 30-2000 pg/mL, with a lower limit of detection of 10 pg/mL for both 2CC-NBOMe and 25I-NBOMe. The method proved suitable for serum clinical toxicology testing. Two severely intoxicated emergency department patients were determined to have serum concentrations of 250 and 2780 pg/mL of 25I-NBOMe using the presented method.

A case of 25I-NBOMe (25-I) intoxication: a new potent 5-HT2A agonist designer drug

CONTEXT

Abuse of synthetic stimulant compounds resulting in significant toxicity is being increasingly reported by poison centers. Toxicologic assessment is complicated by inconsistent manufacturing processes and limited laboratory testing. We describe a case of self-reported exposure to 25-I (25I-NBOMe), a novel phenethylamine derivative, with subsequent quantification in serum.

CASE DETAILS

An 18-year-old male presented to the emergency department (ED) with severe agitation and hallucinations after jumping out of a moving car. He was tachycardiac (150-160 bpm) and hypertensive (150-170 mm Hg systolic and 110 mg Hg diastolic), and required physical restraints and treatment with intravenous lorazepam administration. His symptoms gradually improved and vital signs returned to normal over 48 h, though he continued to have episodes of aggressiveness. An assay was developed by our analytical toxicology laboratory for 25-I, and serum obtained during ED evaluation and treatment was found to contain 0.76 ng/ml of 25-I. Case discussion. For 25I-NBOMe, 25-I is a common abbreviation for 25I-NBOMe, which is a (n-benzyl) phenethylamine in the 2C "family."Initially synthesized for research, cases of self-reported use of 25-I have recently appeared in the literature, some of which contain qualitative urine confirmation. There are no commercially available quantitative assays, and no previous reports have published serum concentrations. 25-I is a potent new synthetic drug with apparent significant behavioral toxicity that can be detected and quantified in serum.