"Spice"-related deaths in and around Munich, Germany: A retrospective look at the role of synthetic cannabinoid receptor agonists in our post-mortem cases over a seven-year period (2014-2020).

Synthetic cannabinoid receptor agonists (SCRAs, "Spice") are a diverse group of recreational drugs, with their structural and pharmacological variability still evolving. Forensic toxicologists often rely on previous reports to assess their role in intoxication cases. This work provides detailed information on the "Spice"-related fatalities around Munich, Germany, from 2014 to 2020. All cases underwent an autopsy. Pharmaceutical and illicit drugs were detected and quantified in post-mortem peripheral blood or liver by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on circumstantial evidence, only those cases for which a prior consumption was suspected underwent additional analyses for SCRAs and other new psychoactive substances in post-mortem blood, liver or antemortem specimens. Drug concentrations, pathological findings at autopsy and case histories were considered to assess and rank the SCRAs' involvement in each death. Concentration ranges for the individual substances in blood were defined and their distribution patterns over the investigated period were determined and correlated with their legal status and local police seizures. We identified 41 different SCRAs among 98 fatalities. 91.8% were male, at a median age of 36 years. SCRAs played a causative role in 51%, contributory role in 26%, and an insignificant role in 23% of cases. In correlation with local police seizures and legal status, 5F-ADB was the most prevalent in our cases, followed by 5F-MDMB-PICA and AB-CHMINACA. Cumyl-CBMICA and 5F-MDMB-P7AICA were among the least frequently detected SCRAs. "Spice"-related fatalities and SCRAs' causative role have significantly decreased among our cases since the German New Psychoactive Substances Act.

A new synthetic cathinone: 3,4-EtPV or 3,4-Pr-PipVP? An unsuccessful attempt to circumvent the German legislation on new psychoactive substances.

Synthetic cathinones comprise psychostimulants with desired effects like euphoria, increased vigilance, appetite suppression, and-mainly depending on certain structural features-entactogenic properties. 3,4-EtPV (1-(bicyclo[4.2.0]octa-1,3,5-trien-3-yl)-2-(pyrrolidin-1-yl)pentan-1-one) was first mentioned in an online drug forum in September 2021, where its imminent synthesis was announced. The goal was to produce a legal alternative to the phenylethylamines already banned by the German NpSG. In February and June 2022, two samples labeled with the name and molecular structure of 3,4-EtPV were analyzed. The molecular structure of the obviously mislabeled compound was elucidated and comprehensively characterized within the ADEBAR project. The synthetic cathinone identified differed from the declared 3,4-EtPV by a 3,4-propylene bridge instead of a 3,4-ethylene bridge and a piperidine ring instead of a pyrrolidine ring. The short name 3,4-Pr-PipVP (3,4-propylene-2-(1-piperidinyl)valerophenone) was suggested as a semisystematic name in collaboration with the European Monitoring Centre for Drugs and Drug Addiction. Herein, the results of the analyses are discussed and will enable forensic laboratories to update their databases quickly and identify 3,4-Pr-PipVP confidently. 3,4-Pr-PipVP is already scheduled under the German NpSG. This study highlights that there are ongoing efforts to deliberately circumvent generic definitions given, for example, in the German NpSG and that (unintentional?) mislabeling can be an issue. The end user purchasing substances online can never be sure that the material actually supplied will be the one ordered, and he might receive an illicit drug instead of an uncontrolled one. Furthermore, the purity is always unknown, creating health risks due to unexpected effects and potencies.

The ADEBAR project: European and international provision of analytical data from structure elucidation and analytical characterization of NPS.

Novel substances for which none or limited analytical data are available constitute a challenge for police and customs forensic laboratories. The time-consuming process of structural elucidation and acquisition of analytical data has been centralized in the ADEBAR project in Germany, co-funded since 2017 by the EU's Internal Security Fund. The project aims to comprehensively characterize substances relevant for forensic-toxicological casework within the analytical competence network. The analytical datasets are distributed digitally through European and (inter)national channels. Additionally, pharmacological evaluation allows for estimating in vivo potency and potential harm required as scientific evidence for legislative amendments. The ADEBAR project contributes to the availability of analytical data on new substances relevant to the daily work of police and customs laboratories. Since the inception of the ADEBAR project, 549 samples have been registered, and 302 substance reports notified to the EMCDDA, including numerous spectrometric and spectroscopic data. In addition, 3,619 mass spectra have been accumulated in ADEBAR mass spectra databases. A central institution for the structure elucidation and acquisition of valid, high-quality analytical data for police and customs forensic laboratories and forensic medicine institutes is important in the future because there does not seem to be an end to the dynamic of novel NPS appearing on the drug market.

Structure elucidation of the novel synthetic cannabinoid Cumyl-Tosyl-Indazole-3-Carboxamide (Cumyl-TsINACA) found in illicit products in Germany.

New chemical moieties continue to appear in synthetic cannabimimetics (SC), the largest group of new psychoactive substances in the EU. We describe the first comprehensive characterisation of the novel SC Cumyl-Tosyl-Indazole-3-Carboxamide (Cumyl-TsINACA) (N-[2-phenylpropan-2-yl]-1-tosyl-1H-indazole-3-carboxamide) from seized case samples. Structure elucidation was performed within the EU-project ADEBAR plus to facilitate confident identification by other researchers and practitioners worldwide. Characteristic MS fragmentations include the cleavage of the sulfonamide bond (S-N), the aryl sulfone bond (C-S) and the elimination rearrangement of SO2 in the side chain. Cumyl-TsINACA is a full receptor agonist at hCB1 (Emax  = 228%) with very weak binding affinity (Ki  = 292 nm) and low functional activity (EC50  = 31 µm). Thermal degradation of Cumyl-TsINACA was observed under GC conditions. The degree to which the tosyl side chain is cleaved due to pyrolysis primarily depends on solvent, the use of glass wool in the liner and injector temperature. The determination of the constitution by NMR spectroscopy was ambiguous due to the high number of neighbouring, non-proton-bearing atoms. Therefore, other possible structures compatible with the NMR correlations were generated using the WebCocon software. The unambiguous structural evidence was finally obtained by spectra comparison after the synthesis of Cumyl-TsINACA. The low thermal stability, as well as the low affinity and potency, renders this compound unfavourable for the use as a psychoactive substance. Thus, we do not expect widespread adoption of this SC.

Dataset allowing for the identification of three new synthetic cannabimimetics featuring a norbornyl methyl side chain by spectrometric and spectroscopic techniques.

Synthetic cannabimimetics (SC) are a diverse group of new psychoactive substances with varying potency and harm potential. New SCs appear on the drug market every year, and reliable and correct identification of these new derivatives independent from the matrix relies on the availability of verified spectra. Three new synthetic cannabimimetics featuring a norbornyl methyl side chain and varying core structure elements were identified in different seizures and forms. Cumyl-BC[2.2.1]HpMeGaClone and Cumyl-BC[2.2.1]HpMINACA were laced onto herbal blends, whereas Cumyl-BC[2.2.1]HpMICA was seized as a pure solid powder. The data collection process involves a comprehensive set of orthogonal analytical techniques allowing for the unambiguous identification of the respective endo- and exo-isomers. Furthermore, the diversity of analytical techniques allows a greater number of laboratories working in the field of forensic chemistry to confidently identify the substances described in our original research article [1]. Structure elucidation and analytical characterisation were performed within the EU-project ADEBAR plus using gas chromatography-mass spectrometry (GC-MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), as well as solid and neat IR spectroscopy, Raman spectroscopy, liquid chromatography-electrospray ionisation-mass spectrometry (LC-ESI-MS), and high resolution (HR)-LC-ESI-MS, and nuclear magnetic resonance (NMR) spectroscopy. The raw analytical data files are included in the Mendeley repository alongside the individual spectra in a universally importable format. The use of the universal JCAMP format for storage of the spectra facilitates database maintenance and enables seamless integration of the verified spectra. Thus, the dataset enables other researchers worldwide to identify these three new SCs confidently.

Cumyl-CBMICA: A new synthetic cannabinoid receptor agonist containing a cyclobutyl methyl side chain.

Since the beginning of the phenomenon of new psychoactive substances (NPS), synthetic cannabinoid receptor agonists (SCRAs) have been the largest and most prevalent subclass of these drugs in Europe. Many countries implemented specific legislation scheduling classes of substances defined on the basis of their chemical structure to reduce supply. We describe the identification and analytical characterization within the EU project ADEBAR plus of 1-(cyclobutylmethyl)-N-(2-phenylpropan-2-yl)-1H-indole-3-carboxamide which resulted in the formal notification through the Early Warning System of the European Monitoring Centre for Drug and Drug Addiction (EMCDDA). This is the first identification of this new SCRA worldwide and the analytical data was distributed (inter-)nationally right after identification in 2019. First, the substance was isolated from the herbal material using preparative high-performance liquid chromatography (HPLC). Structure elucidation and analytical characterization were performed using gas chromatography-mass spectrometry (GC-MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (LC-ESI-qToF-MS), Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The new compound contains a cyclobutyl methyl group as a side chain and has not been described in any patent to our knowledge. Based on the semisystematic nomenclature of SCRAs, we propose Cumyl-CBMICA as a short name for the compound.

Use of UPLC-HRMS/MS for In Vitro and In Vivo Metabolite Identification of Three Methylphenidate-derived New Psychoactive Substances.

The distribution of so-called new psychoactive substances (NPS) as substitute for common drug of abuse was steadily increasing in the last years, but knowledge about their toxicodynamic and toxicokinetic properties is lacking. However, a comprehensive knowledge of their toxicokinetics, particularly their metabolism, is crucial for developing reliable screening procedures and to verify their intake, e.g., in case of intoxications. The aim of this study was therefore to tentatively identify the metabolites of the methylphenidate-derived NPS isopropylphenidate (isopropyl 2-phenyl-2-(2-piperidyl) acetate, IPH), 4-fluoromethylphenidate (methyl 2-(4-fluorophenyl)-2-(piperidin-2-yl) acetate, 4-FMPH) and 3,4-dichloromethylphenidate (methyl 2-(3,4-dichlorophenyl)-2-(piperidin-2-yl) acetate, 3,4-CTMP) using different in vivo and in vitro techniques and ultra-high performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS/MS). Urine samples of male rats were analyzed, and the transfer to human metabolism was done by using pooled human S9 fraction (pS9), which contains the microsomal fraction of liver homogenisate as well as its cytosol. UHPLC-HRMS/MS analysis of rat urine revealed 17 metabolites for IPH (14 phase I and 3 phase II metabolites), 13 metabolites were found for 4-FMPH (12 phase I metabolites and 1 phase II metabolite) and 7 phase I metabolites and no phase II metabolites were found for 3,4-CTMP. pS9 incubations additionally indicated that all investigated substances were primarily hydrolyzed, resulting in the corresponding carboxy metabolites. Finally, these carboxy metabolites should be used as additional analytical targets besides the parent compounds for comprehensive mass spectrometry-based screening procedures.

Toxicokinetics and analytical toxicology of the abused opioid U-48800 - in vitro metabolism, metabolic stability, isozyme mapping, and plasma protein binding.

Due to the risk of new synthetic opioids (NSOs) for human health, the knowledge of their toxicokinetic characteristics is important for clinical and forensic toxicology. U-48800 is an NSO structurally non-related to classical opioids such as morphine or fentanyl and offered for abuse. As toxicokinetic data of U-48800 is not currently available, the aims of this study were to identify the in vitro metabolites of U-48800 in pooled human liver S9 fraction (pS9), to map the isozymes involved in the initial metabolic steps, and to determine further toxicokinetic data such as metabolic stability, including the in vitro half-life (t1/2 ), and the intrinsic (CLint ) and hepatic clearance (CLh ). Furthermore, drug detectability studies in rat urine should be done using hyphenated mass spectrometry. In total, 13 phase I metabolites and one phase II metabolite were identified. N-Dealkylation, hydroxylation, and their combinations were the predominant metabolic reactions. The isozymes CYP2C19 and CYP3A4 were mainly involved in these initial steps. CYP2C19 poor metabolizers may suffer from an increased U-48800 toxicity. The in vitro t1/2 and CLint could be rated as moderate, compared to structural related compounds. After administration of an assumed consumer dose to rats, the unchanged parent compound was found only in very low abundance but three metabolites were detected additionally. Due to species differences, metabolites found in rats might be different from those in humans. However, phase I metabolites found in rat urine, the parent compound, and additionally the N-demethyl metabolite should be used as main targets in toxicological urine screening approaches.

Untargeted metabolomics by high resolution mass spectrometry coupled to normal and reversed phase liquid chromatography as a tool to study the in vitro biotransformation of new psychoactive substances.

In 2016, several synthetic cathinones were seized by the State Bureau of Criminal Investigation Bavaria in Germany. Due to their previous appearances in other countries their metabolism was already investigated in human urine as well as different in vitro models. These investigations were conducted using ordinary metabolism studies for drugs of abuse by using general knowledge about drug metabolism and visual comparison of mass spectra. The present study aimed to use untargeted metabolomics to support and improve those methods that highly depend on the investigators experience. Incubations were conducted using pooled human liver microsomes (pHLM) and the two cathinones 1-phenyl-2-(1-pyrrolidinyl)-1-butanone and 1-phenyl-2-(1-pyrrolidinyl)-1-heptanone. Samples were analyzed by LC-HRMS/MS using a metabolomics workflow consisting of a reversed phase or normal phase separation followed by electrospray ionization and full scan in positive or negative mode. LC-MS data was afterwards statistically evaluated using principal component analysis, t-distributed stochastic neighborhood embedding, and hierarchical clustering. Significant features were then identified using MS/MS. The workflow revealed 24 significant features after 1-phenyl-2-(1-pyrrolidinyl)-1-butanone and 39 after 1-phenyl-2-(1-pyrrolidinyl)-1-heptanone incubation, consisting of adducts, artifacts, isomers, and metabolites. The applied untargeted metabolomics strategy was able to find almost all of the metabolites that were previously described for 1-phenyl-2-(1-pyrrolidinyl)-1-butanone in literature as well as three additional metabolites. Concerning 1-phenyl-2-(1-pyrrolidinyl)-1-heptanone biotransformation in pHLM, merely four metabolites described in primary human hepatocytes and human urine were not found. This study revealed that untargeted metabolomics workflows are well suited to support biotransformation studies at least of the investigated compounds in pHLM.

Different in vitro and in vivo tools for elucidating the human metabolism of alpha-cathinone-derived drugs of abuse.

In vitro and in vivo experiments are widely used for studying the metabolism of new psychoactive substances (NPS). The availability of such data is required for toxicological risk assessments and development of urine screening approaches. This study investigated the in vitro metabolism of the 5 pyrrolidinophenone-derived NPS alpha-pyrrolidinobutyrophenone (alpha-PBP), alpha-pyrrolidinopentiothiophenone (alpha-PVT), alpha-pyrrolidinohexanophenone (alpha-PHP), alpha-pyrrolidinoenanthophenone (alpha-PEP, PV8), and alpha-pyrrolidinooctanophenone (alpha-POP, PV9). First, they were incubated with pooled human liver microsomes (pHLM) or pooled human liver S9 fraction (pS9) for identification of the main phase I and II metabolites. All substances formed hydroxy metabolites and lactams. Longer alkyl chains resulted in keto group and carboxylic acid formation. Comparing these results with published data obtained using pHLM, primary human hepatocytes (PHH), and authentic human urine samples, PHH provided the most extensive metabolism. Second, enzyme kinetic studies showed that the initial metabolic steps were formed by cytochrome P450 isoforms (CYP) CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 resulting in pyrrolidine, thiophene or alkyl hydroxy metabolites depending on the length of the alkyl chain. The kinetic parameters indicated an increasing affinity of the CYP enzymes with increase of the length of the alkyl chain. These parameters were then used to calculate the contribution of a single CYP enzyme to the in vivo hepatic clearance. CYP2C19 and CYP2D6 were mainly involved in the case of alpha-PBP and CYP1A2, CYP2C9 and CYP2C19 in the case of alpha-PVT, alpha-PHP, alpha-PEP, and alpha-POP.

Structural characterization and pharmacological evaluation of the new synthetic cannabinoid CUMYL-PEGACLONE.

The number of new psychoactive substances (NPS) that have emerged on the European market has been rapidly growing in recent years, with a particularly high number of new compounds from the group of synthetic cannabinoid receptor agonists. There have been various political efforts to control the trade and the use of NPS worldwide. In Germany, the Act to control the distribution of new psychoactive substances (NpSG) came into force in November 2016. In this new act, two groups of substances were defined, the group "cannabimimetics/synthetic cannabinoids" covering indole, indazole, and benzimidazole core structures, and a second group named "compounds derived from 2-phenethylamine." Shortly after, the first retailers of "herbal blends" promoted new products allegedly not violating the German NpSG. We describe the identification and structural elucidation of one of the first synthetic cannabinoids not being covered by the NpSG, 5-pentyl-2-(2-phenylpropan-2-yl)-2,5-dihydro-1H-pyrido[4,3-b]indol-1-one. For isolation of the substance a flash chromatography separation was applied. The structure elucidation was performed using gas chromatography-mass spectrometry (GC-MS), gas chromatography-solid state infrared spectroscopy (GC-sIR), liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (LC-ESI-qToF-MS) and nuclear magnetic resonance (NMR) analysis. Additionally, binding affinity towards the cannabinoid receptors CB1 and CB2 and efficacy in a cAMP accumulation assay were measured, showing full agonistic activity and high potency at both receptors. The new compound bears a γ-carboline core structure circumventing the German NpSG and the generic definitions in other national laws. As a semi-systematic name for 2-cumyl-5-pentyl-gamma-carbolin-1-one CUMYL-PEGACLONE is suggested.