Identification of (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone and its 5-pentyl fluorinated analog in herbal incense seized for drug trafficking

UR-144, synthetic cannabinoid receptor agonist, induced cardiomyoblast toxicity mechanism comprises cytoplasmic Ca2+ and DAPK1 related autophagy and necrosis

UR-144, a cannabinoid receptor agonist, is widely used alone or in combination with other synthetic cannabinoids (SCs) all over the world. At overdose, cardiovascular symptoms have been reported and the underlying molecular mechanisms of these adverse effects are not known. It is highly important to clarify the toxic effects of UR-144 for the treatment of poisoning. In the present study, the molecular mechanism of cytotoxic effects of UR-144 is evaluated on a cardiomyoblastic cell line using WST-1 and LDH assays. Apoptosis/necrosis, autophagy, and ROS (reactive oxygen species) levels were determined using flow cytometry. Cytoplasmic Ca²⁺ levels were measured by using a fluorogenic calcium-binding dye. Released and cytoplasmic troponin T levels, a specific marker of cardiotoxicity, were examined with western blot. For the evaluation of the role of DAPK1, on UR-144-induced cell death, DAPK1 activity and DAPK1 protein level were investigated. Its cytotoxic effects increased in a dose-dependent manner for WST-1 and LDH assays, while membrane damage, one of the signs of necrotic cell death, was more remarkable than damage to mitochondria. Cytoplasmic Ca²⁺ levels rose after high-dose UR-144 treatment and inhibition of DAPK1 activity ameliorated UR-144-induced cytotoxicity. Released troponin T significantly increased at a dose of 200 µM. ROS and total antioxidant capacity of cells were both reduced following high dose UR-144 treatment. The results indicated that UR-144-induced autophagic and necrotic cell death might be a consequence of elevated cytoplasmic Ca²⁺ levels and DAPK1 activation. However, in vivo/clinical studies are needed to identify molecular mechanisms of cardiotoxic effects of UR-144.

Synthesis and pharmacological evaluation of newly detected synthetic cannabinoid receptor agonists AB-4CN-BUTICA, MMB-4CN-BUTINACA, MDMB-4F-BUTICA, MDMB-4F-BUTINACA and their analogs

Synthetic cannabinoid receptor agonists (SCRAs) continue to make up a significant portion new psychoactive substances (NPS) detected and seized worldwide. Due to their often potent activation of central cannabinoid receptors in vivo, use of SCRAs can result in severe intoxication, in addition to other adverse health effects. Recent detections of AB-4CN-BUTICA, MMB-4CN-BUTINACA, MDMB-4F-BUTICA and MDMB-4F-BUTINACA mark a continuation in the appearance of SCRAs bearing novel tail substituents. The proactive characterization campaign described here has facilitated the detection of several new SCRAs in toxicological case work. Here we detail the synthesis, characterization, and pharmacological evaluation of recently detected SCRAs, as well as a systematic library of 32 compounds bearing head, tail, and core group combinations likely to appear in future. In vitro radioligand binding assays revealed most compounds showed moderate to high affinity at both CB1 (pK i = < 5 to 8.89 ± 0.09 M) and CB2 (pK i = 5.49 ± 0.03 to 9.92 ± 0.09 M) receptors. In vitro functional evaluation using a fluorescence-based membrane potential assay showed that most compounds were sub-micromolar to sub-nanomolar agonists at CB1 (pEC50 = < 5 to 9.48 ± 0.14 M) and CB2 (pEC50 = 5.92 ± 0.16 to 8.64 ± 0.15 M) receptors. An in silico receptor-ligand docking approach was utilized to rationalize binding trends for CB2 with respect to the tail substituent, and indicated that rigidity in this region (i.e., 4-cyanobutyl) was detrimental to affinity.

Structure-activity relationships of valine, tert-leucine, and phenylalanine amino acid-derived synthetic cannabinoid receptor agonists related to ADB-BUTINACA, APP-BUTINACA, and ADB-P7AICA

Synthetic cannabinoid receptor agonists (SCRAs) remain one the most prevalent classes of new psychoactive substances (NPS) worldwide, and examples are generally poorly characterised at the time of first detection. We have synthesised a systematic library of amino acid-derived indole-, indazole-, and 7-azaindole-3-carboxamides related to recently detected drugs ADB-BUTINACA, APP-BUTINACA and ADB-P7AICA, and characterised these ligands for in vitro binding and agonist activity at cannabinoid receptor subtypes 1 and 2 (CB1 and CB2), and in vivo cannabimimetic activity. All compounds showed high affinity for CB1 (K i 0.299-538 nM) and most at CB2 (K i = 0.912-2190 nM), and most functioned as high efficacy agonists of CB1 and CB2 in a fluorescence-based membrane potential assay and a βarr2 recruitment assay (NanoBiT®), with some compounds being partial agonists in the NanoBiT® assay. Key structure-activity relationships (SARs) were identified for CB1/CB2 binding and CB1/CB2 functional activities; (1) for a given core, affinities and potencies for tert-leucinamides (ADB-) > valinamides (AB-) ≫ phenylalaninamides (APP-); (2) for a given amino acid side-chain, affinities and potencies for indazoles > indoles ≫ 7-azaindoles. Radiobiotelemetric evaluation of ADB-BUTINACA, APP-BUTINACA and ADB-P7AICA in mice demonstrated that ADB-BUTINACA and ADB-P7AICA were cannabimimetic at 0.1 mg kg-1 and 10 mg kg-1 doses, respectively, as measured by pronounced decreases in core body temperature. APP-BUTINACA failed to elicit any hypothermic response up to the maximally tested 10 mg kg-1 dose, yielding an in vivo potency ranking of ADB-BUTINACA > ADB-P7AICA > APP-BUTINACA.

Highly sensitive screening and analytical characterization of synthetic cannabinoids in nine different herbal mixtures

The popularity of new psychoactive substances among drug users has become a public health concern worldwide. Among them, synthetic cannabinoids (SCs) represent the largest, most diversified and fastest growing group. Commonly known as 'synthetic marijuana' as an alternative to cannabis, these synthetic compounds are easily accessible via the internet and are sold as 'herbal incenses' under different brand names with no information about the chemical composition. In the present work, we aim to integrate gas chromatography-tandem mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) data as useful strategy for the identification and confirmation of synthetic cannabinoids present in nine seized herbal incenses. The analysis of all samples allowed the initial identification of 9 SCs, namely 5 napthoylindoles (JWH-018, JWH-073, JWH-122, JWH-210, MAM-2201), APINACA, XLR-11 and CP47,497-C8 and its enantiomer. JWH-018 was the most frequently detected synthetic compound (8 of 9 samples), while APINACA and XLR-11 were only identified in one herbal product. Other non-cannabinoid drugs, including oleamide, vitamin E and vitamin E acetate, have also been detected. Oleamide and vitamin E are two adulterants, frequently added to herbal products to mask the active ingredients or added as preservatives. However, to our knowledge, no analytical data about vitamin E acetate was reported in herbal products, being the first time that this compound is identified on this type of samples. The integration data obtained from the used analytical technologies proved to be useful, allowing the preliminary identification of the different SCs in the mixture. Furthermore, the examination of mass spectral fragment ions, as well as the results of both 1D and 2D NMR experiments, enabled the identification and confirmation of the molecular structure of SCs.

Comprehensive analytical characteristics of N-(adamantan-1-yl)-1- (cyclohexylmethyl)-1H-indazole-3-carboxamide (ACHMINACA)

Purpose

The aim of this study was to clarify the most essential analytical features of N-(adamantan-1-yl)-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (one of the newest cannabimimetics called ACHMINACA), to make them useful for analytical identification of this compound.

Methods

The compound was analyzed by gas chromatography–mass spectrometry, high-resolution liquid chromatography–mass spectrometry, crystal X-ray diffraction and spectroscopic methods such as nuclear magnetic resonance, Raman, and infrared spectroscopies.

Results

Detailed and comprehensive analytical data have been acquired for ACHMINACA.

Conclusions

Although brief descriptions of the partial data of ACHMINACA have appeared recently, this article provides the most detailed and comprehensive analytical data of ACHMINACA to our knowledge. Our data will significantly broaden the knowledge about the compound structure extending the possibility of its orthogonal analysis. The gathered data are useful for forensic, toxicological, and clinical purposes.

Synthetic cannabinoids JWH-018, JWH-122, UR-144 and the phytocannabinoid THC activate apoptosis in placental cells

The increasing use of synthetic cannabinoids (SCBs) in recreational settings is becoming a new paradigm of drug abuse. Although SCBs effects mimic those of the Cannabis sativa plant, these drugs are frequently more potent and hazardous. It is known that endocannabinoid signalling plays a crucial role in diverse reproductive events such as placental development. Moreover, the negative impact of the phytocannabinoid Δ⁹-tetrahydrocannabinol (THC) in pregnancy outcome, leading to prematurity, intrauterine growth restriction and low birth weight is well recognized, which makes women of childbearing age a sensitive group to developmental adverse effects of cannabinoids. Placental trophoblast turnover relies on regulated processes of proliferation and apoptosis for normal placental development. Here, we explored the impact of the SCBs JWH-018, JWH-122 and UR-144 and of the phytocannabinoid THC in BeWo cell line, a human placental cytotrophoblast cell model. All the cannabinoids caused a significant decrease in cell viability without LDH release, though this effect was only detected for the highest concentrations of THC. Moreover, a cell cycle arrest at the G₂/M phase was also observed. JWH-018 and JWH-122 increased reactive oxygen species (ROS) production and THC, UR-144 and JWH-122 caused loss of mitochondrial membrane potential. All the compounds were able to induce caspase-9 activation. The involvement of apoptotic pathways was further confirmed through the significant increase in caspase -3/-7 activities. For UR-144, this effect was reversed by the CB1 antagonist AM281, for JWH-018 and THC this effect was mediated by both cannabinoid receptors CB1 and CB2 while for JWH-122 it was cannabinoid receptor-independent. This work demonstrates that THC and SCBs are able to induce apoptotic cell death. Although they may act through different mechanisms and potencies, the studied cannabinoids have the potential to disrupt gestational fundamental events.

Tentative identification of the metabolites of (1-(cyclohexylmethyl)-1H-indol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone, and the product of its thermal degradation, by in vitro and in vivo methods

Synthetic cannabinoids (SCs), mimicking the psychoactive effects of cannabis, consist of a vast array of structurally diverse compounds. A novel compound belonging to the SC family, (1-(cyclohexylmethyl)-1H-indol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone (named TMCP-CHM in this article) contains a cyclopropane ring that isomerizes during the smoking process, resulting in a ring-opened thermal degradant with a terminal double bond in its structure. Metabolites of TMCP-CHM were tentatively identified in vitro (after incubation of the parent substance with S9 pooled human liver fraction) and in vivo (rat experimental model) studies by accurate-mass liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the identification of the degradant metabolites, and to study biotransformation of parent substance in the human, urine and hair samples from patients, who had ingested the compound and were subsequently admitted to hospital with drug intoxications, were analyzed. Products of mono-, di-, trihydroxylation, carboxylation, and carboxylation combined with hydroxylation of TMCP-CHM and its degradant were detected in human urine. Metabolism of the degradant included addition of water to the terminal double bond followed by dehydration and formation of a cyclic metabolite. Degradant metabolites prevailed in comparison with metabolites of the parent substance in each metabolite group examined, except carboxylation. N-Dealkylated metabolites found in human urine originated only from the degradant. Most of the hydroxy metabolites were detected in human urine in both the free form and as glucuronides. The detection of monohydroxylated (M1.1-M1.3, M/A1.10) and carboxylated/hydroxylated (M4.2, M/A4.3) metabolites of TMCP-CHM and the hydrated form of the monohydroxylated metabolite of the degradant was found to be convenient for routine analysis.

The Chemistry and Pharmacology of Synthetic Cannabinoid Receptor Agonist New Psychoactive Substances: Evolution

Synthetic cannabinoid receptor agonists (SCRAs) are the largest and most structurally diverse class of new psychoactive substances (NPS). Although the earliest SCRA NPS were simply repurposed from historical academic manuscripts or pharmaceutical patents describing cannabinoid ligands, recent examples bear hallmarks of rational design. SCRA NPS manufacturers have applied traditional medicinal chemistry strategies (such as molecular hybridization, bioisosteric replacement, and scaffold hopping) to existing cannabinoid templates in order to generate new molecules that circumvent structure-based legislation. Most SCRAs potently activate cannabinoid type 1 and type 2 receptors (CB₁ and CB₂, respectively), with the former contributing to the psychoactivity of these substances. SCRAs are generally more toxic than the Δ⁹-tetrahydrocannabinol (Δ⁹-THC) found in cannabis, and this may be due to ligand bias, metabolism, or off-target activity. This chapter will chart the evolution of recently identified SCRA NPS chemotypes, as well as their putative manufacturing by-products and thermolytic degradants, and describe structure-activity relationships within each class.

Identification of the Synthetic Cannabinoid 1-(4-cyanobutyl)-N-(2-phenylpropan-2-yl)-1H-indazole-3-carboxamide (CUMYL-4CN-BINACA) in Plant Material and Quantification in Post-Mortem Blood Samples

In May 2016, a new type of synthetic indazole-3-carboxamide cannabinoid (CUMYL-4CN-BINACA) was detected in seized plant material submitted to the Istanbul Council of Forensic Medicine by the National Police Office. The major ingredient in this material was purified using preparative liquid chromatography, and its structure was identified using liquid chromatography-high-resolution mass spectrometry (LC-HR/MS), gas chromatography-electron ionization/mass spectrometry (GC-EI/MS), nuclear magnetic resonance (NMR) spectroscopy and Fourier transform-infrared spectroscopy (FT-IR). Using HR-MS, the molecular formula of the compound was determined to be C22H24N4O (MW = 360.1950). The 1H and 13C-NMR and FT-IR spectrometric data revealed that the structure of compound was 1-(4-cyanobutyl)-N-(2-phenylpropan-2-yl)-1H-indazole-3-carboxamide (CUMYL-4CN-BINACA). After identification, it was quickly added to our generic drug list, and an ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method was developed to determine its presence in blood samples. This study reports on the identification of CUMYL-4CN-BINACA in plant material using LC-HR/MS, GC-EI/MS, NMR and FT-IR as well as a validated method for quantification of CUMYL-4CN-BINACA in post-mortem blood samples by UPLC-MS-MS analysis. The quantification method has been validated in terms of linearity (0.1-50 ng/mL), selectivity, intra- and inter-assay accuracy and precision (CV < 15%), recovery (94-99%), limit of detection (0.07 ng/mL) and limit of quantification (0.1 ng/mL). Matrix effects, stability and process efficiency were also assessed. The method has been applied to 2,350 post-mortem blood samples from the autopsy cases in the Morgue Department of the Council of Forensic Medicine (Istanbul, Turkey) between 1 July 2016 and 31 December 2016.

Effects of bioisosteric fluorine in synthetic cannabinoid designer drugs JWH-018, AM-2201, UR-144, XLR-11, PB-22, 5F-PB-22, APICA, and STS-135

Synthetic cannabinoid (SC) designer drugs featuring bioisosteric fluorine substitution are identified by forensic chemists and toxicologists with increasing frequency. Although terminal fluorination of N-pentyl indole SCs is sometimes known to improve cannabinoid type 1 (CB1) receptor binding affinity, little is known of the effects of fluorination on functional activity of SCs. This study explores the in vitro functional activities of SC designer drugs JWH-018, UR-144, PB-22, and APICA, and their respective terminally fluorinated analogues AM-2201, XLR-11, 5F-PB-22, and STS-135 at human CB1 and CB2 receptors using a FLIPR membrane potential assay. All compounds demonstrated agonist activity at CB1 (EC50 = 2.8-1959 nM) and CB2 (EC50 = 6.5-206 nM) receptors, with the fluorinated analogues generally showing increased CB1 receptor potency (∼2-5 times). Additionally, the cannabimimetic activities and relative potencies of JWH-018, AM-2201, UR-144, XLR-11, PB-22, 5F-PB-22, APICA, and STS-135 in vivo were evaluated in rats using biotelemetry. All SCs dose-dependently induced hypothermia and reduced heart rate at doses of 0.3-10 mg/kg. There was no consistent trend for increased potency of fluorinated SCs over the corresponding des-fluoro SCs in vivo. Based on magnitude and duration of hypothermia, the SCs were ranked for potency (PB-22 > 5F-PB-22 = JWH-018 > AM-2201 > APICA = STS-135 = XLR-11 > UR-144).

The Influence of Synthetic Cannabinoid UR-144 on Human Psychomotor Performance--A Case Report Demonstrating Road Traffic Risks

OBJECTIVE

UR-144 [(1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)-methanone] is a synthetic cannabinoid, which has been detected in many "legal highs" seized from the global drug market since the beginning of 2012. It gained popularity as a "legal" alternative to classic cannabis in countries where it was not controlled. The popularity of UR-144 means that this substance is also abused by individuals driving motor vehicles. This article describes a case of driving under the influence (DUI) of UR-144. The aim of the undertaken case analysis and presenting description of pharmacological similarity of THC and UR-144 is to answer the question whether UR-144 can produce effects incompatible with safe driving.

METHODS

Blood from the driver was obtained by a physician approximately 2 h after the collision and 4.5 h after self-reported dosing. Police from the crash site provided behavioral observations, and the physician performed medical examination. Blood was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The developed method was described in detail. The method was linear in the range of 0.5-50 ng/mL; the precision and accuracy values obtained were less than 15%. The symptoms observed by police and physician who collected the blood sample were described.

RESULTS

In the blood sample collected from the driver, UR-144 and its major pyrolysis product [1-(1-pentyl-1H-indol-3-yl)-3-methyl-2-(propan-2-yl)but-3-en-1-one] were detected. Whole-blood concentration of UR-144 was 14.6 ng/mL. The result of blood analysis and observed symptoms clearly indicated that the driver was under the influence of UR-144.

CONCLUSIONS

UR-144 produces effects and impairment similar to or even more dangerous than delta-9-tetrahydrocannabinol (Δ(9)-THC), making it unsafe for driving. Therefore, UR-144 should be treated as a potentially dangerous substance in traffic safety.

Genotoxic properties of representatives of alkylindazoles and aminoalkyl-indoles which are consumed as synthetic cannabinoids

Synthetic cannabinoids (SCs) cause similar effects as cannabis and are sold in herbal mixtures. Recent investigations indicate that some of these drugs possess genotoxic properties. Therefore, we tested representatives of two groups, namely, aminoalkylindoles (AM-2201 and UR-144) and 1-alkylindazoles (5F-AKB-48 and AM-2201-IC) in single cell gel electrophoresis and micronucleus (MN) assays with human lymphocytes and in Salmonella/microsome assays. All drugs except AM-2201 caused DNA-migration, the LOELs were between 50 and 75 µM. Furthermore, all SCs caused inhibition of cell division and significant induction of MN which reflect structural and numerical chromosomal aberrations. The LOEL values were 50 µM for UR-144 and 5-AKB-48 and 75 µM for the other drugs. Also the levels of nucleoplasmatic bridges which are formed from dicentric chromosomes were elevated under identical conditions while the frequencies of nuclear buds were not affected. These findings show that representatives of both groups cause chromosomal damage while the negative results in Salmonella assays (in strains TA98, TA100, TA1535, TA1537 and TA102) in absence and presence of metabolic activation indicate that they do not induce gene mutations. Taken together, these findings indicate that SCs may cause adverse health effects in users as a consequence of damage of the genetic material.

Qualitative analysis of seized synthetic cannabinoids and synthetic cathinones by gas chromatography triple quadrupole tandem mass spectrometry

Designer drugs are analogues or derivatives of illicit drugs with a modification of their chemical structure in order to circumvent current legislation for controlled substances. Designer drugs of abuse have increased dramatically in popularity all over the world for the past couple of years. Currently, the qualitative seized-drug analysis is mainly performed by gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) in which most of these emerging designer drug derivatives are extensively fragmented not presenting a molecular ion in their mass spectra. The absence of molecular ion and/or similar fragmentation pattern among these derivatives may cause the equivocal identification of unknown seized-substances. In this study, the qualitative identification of 34 designer drugs, mainly synthetic cannabinoids and synthetic cathinones, were performed by gas chromatography-triple quadrupole-tandem mass spectrometry with two different ionization techniques, including electron ionization (EI) and chemical ionization (CI) only focusing on qualitative seized-drug analysis, not from the toxicological point of view. The implementation of CI source facilitates the determination of molecular mass and the identification of seized designer drugs. Developed multiple reaction monitoring (MRM) mode may increase sensitivity and selectivity in the analysis of seized designer drugs. In addition, CI mass spectra and MRM mass spectra of these designer drug derivatives can be used as a potential supplemental database along with EI mass spectral database.

Analysis of UR-144 and its pyrolysis product in blood and their metabolites in urine

UR-144 [(1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone] is a synthetic cannabinoid, which has been detected in many herbal blends, resinous samples and powders seized from the Polish drug market since the beginning of 2012. This paper presents the case of intoxication by this substance. A complete picture of the symptoms observed by a witness, paramedics and medical doctors are given. In the analysis of powder residues from the plastic bag seized from the intoxicated person by gas chromatography-mass spectrometry (GC-MS), UR-144 and its major pyrolysis product [1-(1-pentyl-1H-indol-3-yl)-3-methyl-2-(propan-2-yl)but-3-en-1-one] were detected. Both substances were also identified in a blood sample collected on admission of the patient to hospital using liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS). Blood concentration of UR-144 was 6.1 ng/mL. A urine sample collected at the same time was analyzed by liquid chromatography-quadruple time-of-flight tandem mass spectrometry (LC-QTOF-MS). The parent substance and its pyrolysis products were not detected in urine, while their five metabolites were found. The experiments allowed the location of derivative groups to be established, and thus elucidate rough structures of the metabolites; a dihydroxylated metabolite of UR-144 and mono-, dihydroxylated and carboxylated metabolites of its pyrolysis product were identified.

Identification and quantification of synthetic cannabinoids in 'spice-like' herbal mixtures: a snapshot of the German situation in the autumn of 2012

Synthetic compounds mimicking cannabis-like effects are a recent trend. Currently, these so-called synthetic cannabinoids are the largest and fastest growing class of newly appearing designer drugs. Many national authorities are continuously adapting their regulations to keep pace with the permanently changing variety of compounds. We have analyzed eight herbal smoking blends containing synthetic cannabinoids. Altogether, nine compounds could be identified, namely AM-2201, AM-2201-pMe (MAM-2201), AM-1220, AM-1220-azepane, UR-144, XLR-11, JWH-122-pentenyl, AM-2232, and STS-135. Newly appearing compounds were isolated by column chromatography and their structures elucidated by 1D- and 2D-nuclear magnetic resonance (NMR) experiments. In addition, the compounds were investigated by electron ionization-mass spectrometry (EI-MS) and electrospray ionization-tandem mass spectrometry (ESI-MS/MS) to complete the physicochemical dataset. Based on the purified compounds a universal gas chromatography-mass spectrometry (GC-MS) method was developed for the identification and quantification of these compounds in commercial smoking blends. By applying this method, up to five different compounds could be found in such products showing total concentrations from 72 to 303 mg/g smoking blend while individual compounds ranged from 0.4 to 303 mg/g. (1)H NMR spectra of the chiral compounds AM-1220 and its azepane-isomer recorded in the presence of 1 equivalent of (R)-(+)-α-methoxy-α-trifluoromethylphenylacetic acid (MTPA, Mosher's acid) showed them to be racemic mixtures.