Identification and quantitation of two cannabimimetic phenylacetylindoles JWH-251 and JWH-250, and four cannabimimetic naphthoylindoles JWH-081, JWH-015, JWH-200, and JWH-073 as designer drugs in illegal products

Six cannabimimetic indoles have been identified as adulterants in herbal or chemical products being sold illegally in Japan, with four of the compounds being new as adulterants to our knowledge. The identifications were based on analyses using gas chromatography–mass spectrometry, liquid chromatography–mass spectrometry, high-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy. The first two compounds were identified as phenylacetyl indoles JWH-251 (2-(2-methylphenyl)-1-(1-pentyl-1H-indol-3-yl)ethanone; 1) and its demethyl-methoxylated analog JWH-250 (2-(2-methoxyphenyl)-1-(1-pentyl-1H-indol-3-yl)ethanone; 2). Compound 2 was identical to that found as an adulterant in the UK and in Germany in 2009. The third compound was naphthoylindole JWH-081 (1-(4-methoxynaphthalenyl)-(1-pentyl-1H-indol-3-yl)methanone; 3), and the fourth was JWH-073 (1-naphthalenyl(1-butyl-1H-indol-3-yl)methanone; 4), which had been identified as an adulterant in our previous study. Two additional compounds were JWH-015 (1-naphthalenyl(2-methyl-1-propyl-1H-indol-3-yl)methanone; 5) and JWH-200 (1-naphthalenyl(1-(2-(4-morpholinyl)ethyl)-1H-indol-3-yl)methanone; 6). Compounds 1–4 and 6 were reported to be synthetic cannabinoids with selective affinity for cannabinoid CB₁ receptors, while compound 5 was reported to be a selective CB₂ receptor agonist causing immunosuppressive effects without psychotropic affects. One product contained both CB₁ and CB₂ receptor agonists in our collection. Quantitative analyses of the six cannabimimetic compounds in 20 products revealed that there was large variation in concentrations of the detected compounds among products; for herbal cutting products, the total amounts of these cannabinoids ranged from 26 to 100 mg.     

Identification of two new-type synthetic cannabinoids, N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA), and detection of five synthetic cannabinoids, AM-1220, AM-2233, AM-1241, CB-13 (CRA-13), and AM-1248, as designer drugs in illegal products

Two new-type synthetic cannabinoids, N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA, 1) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA, 2), have been identified as designer drugs in illegal products being sold in Japan. The identification was based on liquid chromatography-mass spectrometry (LC-MS), gas chromatography-mass spectrometry (GC-MS), high-resolution MS and nuclear magnetic resonance (NMR) analyses. Both mass and NMR spectrometric data revealed that 1 was 1-pentyl-N-tricyclo[3.3.1.1^3,7]dec-1-yl-1H-indole-3-carboxamide, and 2 was 1-pentyl-N-tricyclo[3.3.3.1.^3,7]dec-1-yl)-1H-indazole-3-carboxamide. Although many of the synthetic cannabinoids detected in illegal products, such as JWH-018, have a 3-carbonyl indole moiety, compounds 1 and 2 are a new type of synthetic cannabinoid having an amide and an adamantyl group, and 2 also has an indazole group in place of an indole group. There has been no synthetic, chemical, or biological information about 1 or 2 until now, making this the first report of these cannabimimetic compounds (1 and 2) as designer drugs. In addition, five synthetic cannabinoids, AM-1220, AM-2233, AM-1241, CB-13 (CRA-13), and AM-1248, are also described herein as newly distributed designer drugs in Japan.     

Identification and quantitation of JWH-213, a cannabimimetic indole, as a designer drug in a herbal product

In our survey of designer drugs in the Japanese market, a cannabimimetic indole was identified as a new active compound in a herbal product. The structure of this compound was elucidated by liquid chromatography–photodiode array–mass spectrometry (LC–PDA–MS), gas chromatography–mass spectrometry (GC–MS), high-resolution MS, and nuclear magnetic resonance (NMR) analyses. The compound was finally identified as (4-ethyl-1-naphthalenyl)(2-methyl-1-pentyl-1H-indol-3-yl)methanone (JWH-213), an indole-based cannabinoid receptor ligand. To our knowledge, this is the first finding of JWH-213 as a designer drug in a herbal product. The quantitative LC–PDA analysis showed that the JWH-213 content in the product was 252 mg/pack.     

Identification and quantitation of two benzoylindoles AM-694 and (4-methoxyphenyl)(1-pentyl-1<Emphasis Type="Italic">H</Emphasis>-indol-3-yl)methanone,and three cannabimimetic naphthoylindoles JWH-210, JWH-122, and JWH-019 as adulterants in illegal products obtained via the Internet

During our careful surveillance of unregulated drugs, we found five new compounds used as adulterants in herbal and drug-like products obtained via the Internet. These compounds were identified by liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry, accurate mass spectrometry, and nuclear magnetic resonance spectroscopy. The first compound identified was a benzoylindole AM-694, which is 1-[(5-fluoropentyl)-1H-indol-3-yl]-(2-iodophenyl)methanone (1). The second compound was (4-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone (2), which was also classified as a benzoylindole. The three other compounds were identified as naphthoylindoles JWH-210 (4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone; 3), JWH-122 (4-methylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone; 4), and JWH-019 (1-hexyl-3-(naphthalen-1-oyl)indole; 5). All compounds except compound 2 had been reported to be cannabinoid receptor agonists. For quantitation of the five compounds and previously reported compounds, each product was extracted with methanol under ultrasonication to prepare a test solution for analysis by liquid chromatography with ultraviolet detection. Each compound detected in 43 commercial products showed large variation in content ranging from 4.0 to 359 mg per pack.     

Identification and quantitation of cannabimimetic compound JWH-250 as an adulterant in products obtained via the Internet

During our careful survey of unregulated drugs in Tokyo, a new compound was disclosed as an adulterant in herbal and powder products. This compound was found to have a molecular weight of 335 by liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry, and the accurate mass measurement suggested an elementary composition of C₂₂H₂₆NO₂. Using these mass data together with those obtained by nuclear magnetic resonance analysis, the compound was identified as 1-pentyl-3-(2-methoxyphenylacetyl)indole (JWH-250), which had been reported by Huffman and coworkers in 2005. This compound was classified as a phenylacetylindole and a cannabinoid receptor agonist. For quantitation of the compound in herbal and powder products, each product was extracted with methanol under ultrasonication to prepare the solution for analysis by liquid chromatography with ultraviolet detection. The contents of JWH-250 in five products ranged from 77.4 to 165 mg per pack.     

Identification of a synthetic cannabinoid A-836339 as a novel compound found in a product

As a part of the work conducted in our laboratory, we encountered a case in which new chemical compound was contained in a certain product. This compound was found to have a molecular weight of 310 Da by liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry. Accurate mass spectrometry measurements showed that the compound had an elemental composition of C₁₆H₂₆N₂O₂S. Using these mass data together with those obtained by nuclear magnetic resonance analysis and X-ray crystallographic analysis, this compound was identified as N-[3-(2-methoxyethyl)-4,5-dimethyl-2(3H)-thiazolylidene]-2,2,3,3-tetramethylcyclopropanecarboxamide, which was reported in 2009 and named A-836339. It was described as a thiazol derivative and a selective agonist of G-protein-coupled cannabinoid receptor CB₂. This is the first report to identify this compound in a dubious product.     

New cannabimimetic indazole derivatives, N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide (AB-PINACA) and N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA) identified as designer drugs in illegal products

Two new cannabimimetic indazole derivatives, N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide (AB-PINACA, 1) and N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA, 2), have been identified as designer drugs in illegal products. These identifications were based on liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry, high-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy. Because there have been neither chemical nor pharmacological data about compound 1 until now, this is the first report of this compound. Compound 2 was reported as a potent cannabinoid CB₁ receptor modulator when synthesized by Pfizer in 2009; but this is the first report of its detection in illegal products.     

Identification and quantitation of a benzoylindole (2-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone and a naphthoylindole 1-(5-fluoropentyl-1H-indol-3-yl)-(naphthalene-1-yl)methanone (AM-2201) found in illegal products obtained via the Internet and their cannabimimetic effects evaluated by in vitro [35S]GTP��S binding assays

During our careful surveillance of unregulated drugs in January to February 2011, we found two new compounds used as adulterants in herbal products obtained via the Internet. These compounds were identified by liquid chromatography?Cmass spectrometry, gas chromatography-mass spectrometry, accurate mass spectrometry, and nuclear magnetic resonance spectroscopy. The first compound identified was a benzoylindole (2-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone (1), which is a positional isomer of (4-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone (RCS-4, 4). The second compound was 1-(5-fluoropentyl-1H-indol-3-yl)-(naphthalene-1-yl)methanone (AM-2201, 2). The compound 2 has been reported to be a cannabinoid receptor agonist. Because the cannabimimetic effects of compounds 1 and 4 have not been reported to date, their biological activities were evaluated by measuring the activation of [³⁵S] guanosine-5??-O-(3-thio)-triphosphate binding to guanine nucleotide-binding proteins, together with those of other synthetic cannabimimetic compounds. For quantitation of the above two compounds (1 and 2) and previously identified compounds (AM-694, 3; JWH-122, 5; RCS-4, 4), each product was extracted with methanol under ultrasonication to prepare a sample solution for analysis by liquid chromatography with ultraviolet detection. Each of four commercial products contained some of cannabimimetic indoles 1?C5; their contents ranged from 14.8 to 185 mg per pack.     

Identification of the cannabimimetic AM-1220 and its azepane isomer (N-methylazepan-3-yl)-3-(1-naphthoyl)indole in a research chemical and several herbal mixtures

Recently, a large number of synthetic cannabinoids have been identified in herbal mixtures. Moreover, an even higher number of cannabimimetic compounds are currently distributed as research chemicals on a gram to kilogram scale via several online trading platforms. As this situation leads to a large number of new cannabimimetics and the occurrence of isobaric substances, the analysis of such compounds using mass spectroscopy (MS) involves the risk of incorrect assignments of mass spectra. In certain cases, this leads to considerable analytical challenges. In the majority of cases, these challenges can only be mastered by combining multiple analytical techniques. We purchased a so-called research chemical advertised as the cannabimimetic compound [(N-methylpiperidin-2-yl)methyl]-3-(1-naphthoyl)indole (AM-1220) via an Internet platform. Analysis of the microcrystalline substance using gas chromatography (GC)–MS indicated the presence of pure AM-1220. However, after further purity testing utilizing thin-layer chromatography we were surprised to see an additional spot indicating a mixture of two substances with highly similar physicochemical properties. After isolation, high-resolution mass spectroscopy (HR-MS) revealed an elemental composition of C₂₆H₂₆N₂O for both substances, proving the presence of two isobaric substances. Moreover, GC–MS and LC-HR-MS/MS experiments indicated two naphthoylindoles featuring different heterocyclic substituents at the indole nitrogen. Nuclear magnetic resonance spectroscopy verified the presence of the highly potent cannabimimetic AM-1220 and its azepane isomer. Interestingly, only a few weeks after purchasing the powder we also detected both substances in a similar proportion in several herbal mixtures for the first time.     

New-generation azaindole-adamantyl-derived synthetic cannabinoids

Purpose

This work reports the synthesis and pharmacological and analytical data for a new series of recently identified azaindole-adamantyl-derived synthetic cannabinoids (SCs).

Methods

Each SC was synthesised using an efficient and divergent synthesis, and assessed by electron ionisation mass spectrometry (EIMS). The cannabimimetic activity of each compound was conducted using a fluorometric imaging plate reader (FLIPR) assay.

Results

The described EIMS method and retention time by gas chromatography were able to effectively differentiate each of the analogues regardless of the bicyclic core. For the first time in these SC structures, the bicyclic ring system was shown to have an impact on the cannabimimetic activities in the fluorometric assay of membrane potential. Analogues ranged from moderately potent at both CB₁ and CB₂ (e.g., AP4AIC EC₅₀?=?160 nM and EC₅₀?=?64 nM, respectively) to not active at either cannabinoid receptor (AP4AICA, AP5AICA, and APIC).

Conclusions

Further investigation into receptor selectivity surrounding these bicyclic cores could prove useful for future therapeutic applications.

     

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

Four herbal incense products were seized from suspected drug abusers in Korea. The major ingredients in the herbal incense samples were purified, and their structures were elucidated using gas chromatography–electron ionization–mass spectrometry (GC–EI–MS), liquid chromatography–time-of-flight–mass spectrometry (LC–TOF–MS), and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. As a result, ingredients in the herbal incense were identified as (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone and its 5-pentyl fluorinated analog [1-(5-fluoropentyl)indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone. The former is being sold via the Internet as a "research chemical" named UR-144, and the latter is sold as 5F-UR-144. UR-144 is a selective full agonist of CB₂ cannabinoid receptor, and was first developed by Abbott Laboratories as an analgesic. It exhibits analgesic activity against both neuropathic and inflammatory pain associated mainly with the CB₂ receptor, but shows less psychotropic effects associated with the CB₁ receptor. Fluorination of the N-pentyl side chain of cannabimimetic compounds increases their cannabinoid receptor affinity such as with AM-2201, which shows both increased analgesic and psychotropic effects simultaneously. UR-144 and 5F-UR-144 can be classified as research chemicals based on their analgesic effects, but in practice are abused as psychotropic agents and can cause unexpected toxic effects. Thus, the trade and diversion of these chemicals should be monitored carefully for possible abuse. To our knowledge, this is the first report disclosing cyclopropylcarbonylindoles in herbal products.     

Comprehensive analytical and structural characteristics of methyl 3,3-dimethyl-2-(1-(pent-4-en-1-yl)-1H-indazole-3-carboxamido)butanoate (MDMB-4en-PINACA)

Purpose

The purpose of the study was to evaluate a complete analytical and structural characterization of methyl 3,3-dimethyl-2-(1-(pent-4-en-1-yl)-1H-indazole-3-carboxamido)butanoate (MDMB-4en-PINACA), a novel synthetic cannabinoid being the analogue of 5F-ADB.

Methods

The compound was analyzed by gas chromatography–mass spectrometry (GC–MS), high-resolution liquid chromatography–mass spectrometry (LC–MS), X-ray diffraction and spectroscopic methods, such as nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR) spectroscopies. To derive MDMB-4en-PINACA molecular geometry and to assign infrared absorption bands, quantum calculations with the employment of density functional theory were also used.

Results

We present a wide range of chromatographic and spectroscopic data supported with theoretical calculations allowing to identify MDMB-4en-PINACA.

Conclusions

To our knowledge, this is the first report presenting a comprehensive analytical and structural characterization of MDMB-4en-PINACA obtained by 1D and 2D NMR, GC–MS, LC–MS(/MS), attenuated total reflection-FTIR spectroscopy, powder X-ray diffraction and quantum chemical calculations. The presented results not only broaden the knowledge about this psychoactive substance but also are useful for forensic and clinical purposes.

     

[1-(Tetrahydropyran-4-ylmethyl)-1H-indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone: a new synthetic cannabinoid identified on the drug market

A new synthetic cannabinoid, [1-(tetrahydropyran-4-ylmethyl)-1H-indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone, was identified in several resinous samples seized by law enforcement officers in Poland. Its identification was based on liquid chromatography–electrospray ionization–quadrupole time-of-flight–mass spectrometry, gas chromatography–electron ionization–mass spectrometry, one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy, and Fourier-transform infrared spectroscopy. The reported substance was first developed by Abbott Laboratories and patented under the name “A-834,735”. It is a potent agonist of both CB₁ and CB₂ receptors. Although A-834,735 shows moderate selectivity to CB₂ receptor, it exhibits a CB₁ affinity similar to that of ?⁹-tetrahydrocannabinol. The drug has recently become available in online shops. To our knowledge, this is the first report to disclose a synthetic cannabinoid containing a (tetrahydropyran-4-yl)methyl structure in products seized from the drug market.     

Identification and quantitation of two new naphthoylindole drugs-of-abuse, (1-(5-hydroxypentyl)-1H-indol-3-yl)(naphthalen-1-yl)methanone (AM-2202) and (1-(4-pentenyl)-1H-indol-3-yl)(naphthalen-1-yl)methanone, with other synthetic cannabinoids in unregulated “herbal” products circulated in the Tokyo area

During our continual surveillance of unregulated drugs in May–June 2011, we found two new compounds as adulterants in herbal products obtained at shops in the Tokyo area. These compounds were identified by liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry, accurate mass spectrometry, and nuclear magnetic resonance spectroscopy. The first compound identified was a naphthoylindole (1-(5-hydroxypentyl)-1H-indol-3-yl)(naphthalen-1-yl)methanone (AM-2202, 1), which is a side-chain hydroxyl analogue of JWH-018. The second compound was (1-(4-pentenyl)-1H-indol-3-yl)(naphthalen-1-yl)methanone (2), which is side-chain double bond analogue of JWH-018. This is the first report to identify 1 and 2 in a commercial “herbal” product to our knowledge. For quantitation of the above compounds 1 and 2, and chemical analysis for previously reported compounds (AM-2201, 3; JWH-203, 4; JWH-019, 7; JWH-210, 8; mitragynine, 9), each product was extracted with methanol under ultrasonication to prepare solutions for analysis by liquid chromatography with ultraviolet detection. For the sake of identifying JWH-203 (4) and its positional isomers [JWH-203-3-chloroisomer (5) and 4-chloroisomer (6)] correctly, simultaneous liquid chromatography analysis on fluorocarbon-bonded silica gel column was performed. And a case report of commercially available products containing synthetic cannabinoids 7 and 8, and a natural occurring alkaloid 9, was also shown. Each of 6 commercially circulated products contained compounds 1–4 and 7–9; the amounts of the compounds ranged from 4.1 to 222 mg per pack.     

Identification of a new synthetic cannabinoid in a herbal mixture: 1-butyl-3-(2-methoxybenzoyl)indole

Two unknown cannabimimetic compounds were detected in a seized herbal mixture after gas chromatography–mass spectrometry (GC–MS) screening. To elucidate the chemical structures, 0.3 g of the dried plant material was extracted with methanol and concentrated under reduced pressure. The extract was purified by silica gel column chromatography with methylene chloride and methanol. Pure compounds were isolated by preparative high-performance liquid chromatography (HPLC) and then analyzed by electrospray ionization (ESI) mass spectrometry (MS) with direct flow injection, high-resolution ESI-time-of-flight (TOF)–MS and one-dimensional and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. GC–MS spectra showed that the base ion at m/z 321 for compound 1 was the same as that of 1-pentyl-3-(4-methoxybenzoyl)indole (RCS-4), and the fragment ions were almost the same as those of RCS-4. The GC–MS spectrum of compound 2 was very similar to that of compound 1 except that the mass numbers of the fragment ions at m/z 290, 200, 186, and 173 of compound 2 were equally smaller than those of compound 1 by 14 amu. From these GC–MS results, compound 1 was assumed to be the 2- or 3-methoxy isomer of RCS-4, and compound 2 was assumed to be a 1-butylindole homologue of compound 1. The ESI mass spectra showed a single peak at m/z 322.33 for compound 1 and a single peak at m/z 308.25 for compound 2, which showed the masses of the protonated ions. High-resolution TOF–MS spectra showed the accurate mass numbers of protonated molecular ions at m/z 322.180512 for compound 1 and at m/z 308.164895 for compound 2, suggesting the molecular formulas of C₂₁H₂₃NO₂ and C₂₀H₂₁NO₂, respectively. The ¹H NMR spectra showed signals that suggested 23 and 21 protons for compounds 1 and 2, respectively, while the respective ¹³C NMR spectra showed 21 and 20 carbon signals. All protons and carbons were assigned by their couplings and correlations observed in ¹H–¹H correlation spectroscopy (COSY), ¹H–¹³C heteronuclear multiple bond correlation (HMBC), and ¹H–¹³C heteronuclear single quantum coherence (HSQC) spectra. On the basis of the spectral data, compound 1 was identified as the 2-methoxy isomer of RCS-4; compound 2 was identified for the first time as 1-butyl-3-(2-methoxybenzoyl)indole. Phenazepam and 5-methoxy-N,N-diallyltryptamine (5-MeO-DALT) were also identified as coexisting drugs in the herbal mixture. The contents of compounds 1 and 2 in the mixture were calculated to be 22.4 and 3.45 mg/g, respectively.     

Desferrithiocin analogue uranium decorporation agents

Purpose: Previous systematic structure-activity studies of the desferrithiocin (DFT) platform have allowed the design and synthesis of analogues and derivatives of DFT that retain the exceptional iron-clearing activity of the parent, while eliminating its adverse effects. We hypothesized that a similar approach could be adopted to identify DFT-related analogues that could effectively decorporate uranium.

Materials and methods: The decorporation properties of nine DFT-related analogues were determined in a bile duct-cannulated rat model. Diethylenetriaminepentaacetic acid (DTPA) served as a positive control. Selected ligands also underwent multiple and delayed dosing regimens. Uranium excretion in urine and bile or stool was determined by inductively coupled plasma mass spectroscopy (ICP-MS); tissue levels of uranium were also assessed.

Results: The two best clinical candidates are (S)-4,5-dihydro-2-[2-hydroxy-4-(3,6,9-trioxadecyloxy)phenyl]-4-methyl-4-thiazolecarboxylic acid [(S)-4′-(HO)-DADFT-PE (9)], with a 57% reduction in kidney uranium levels on oral (p.o.) administration and (S)-4,5-dihydro-2-[2-hydroxy-3-(3,6,9-trioxadecyloxy)phenyl]-4-methyl-4-thiazolecarboxylic acid [(S)-3′-(HO)-DADFT-PE (10)], with a 62% renal reduction on p.o. administration. The majority of the metal excretion promoted by these analogues is in the bile, thus further reducing kidney actinide exposure.

Conclusions: While 9 administered p.o. or subcutaneously (s.c.) immediately post-metal is an effective decorporation agent, withholding the dose (s.c.) until 4 h reduced the activity of the compound. Conversion of 9 to its isopropyl ester may circumvent this issue.     

Synthesis and in vivo studies of a specific monoamine oxidase B inhibitor: 5-[4-(benzyloxy)phenyl]-3-(2-cyanoethyl)-1,3,4-oxadiazol-[11C]-2(3H)-one

We report the radiochemical synthesis of a specific MAO B inhibitor, namely 5-[4-(benzyloxy)phenyl]-3-(2-cyanoethyl)-1,3,4-oxadiazol-[¹¹C]-2(3H)-one (2b) (in vitro IC₅₀=4nM and selectivity over 71000 for MAO B), by cyclization of its hydrazide precursor1 with [¹¹C]phosgene. The reaction occurred within 2 min. The product obtained after HPLC purification,2b, had a high specific activity (11.1–22.2 GBq/µmol), allowing its use in experiments as a radiotracer in vivo. Biodistribution of2b in the CNS and in the peripheral organs of the rat, and positron emission tomography (PET) studies in the living baboon brain, pretreated or not withl-deprenyl (1 mg/kg, 1 h), an irreversible MAO B-specific inhibitor, were undertaken. The results showed a good uptake of2b in all organs of the rat, with a rapid clearance from the blood (10 min). Metabolite analyses in plasma and in the diencephalon of the rat showed that2b was the only radioactive compound in brain structure whereas in plasma three other radioactive products appeared. PET experiments show that in thel-deprenyl-pretreated baboon brain, specific binding of2b represents around 70% of total radioactivity, whereas in the blood and plasma the radioactivity cleared rapidly (15 min).     

Analysis of azepane isomers of AM-2233 and AM-1220, and detection of an inhibitor of fatty acid amide hydrolase [3′-(aminocarbonyl)(1,1′-biphenyl)-3-yl]-cyclohexylcarbamate (URB597) obtained as designer drugs in the Tokyo area

During our careful survey of unregulated drugs from November 2011 to January 2012 in the Tokyo area, we found two new compounds in commercial products. The first was identified as the benzoylindole (2-iodophenyl)[1-(1-methylazepan-3-yl)-1H-indol-3-yl]methanone (2), which is the azepane isomer of AM-2233 (1). Compound 2 was isolated by silica gel column chromatography, and was identified through a combination of liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry, accurate mass spectrometry, and nuclear magnetic resonance spectroscopy. The second compound was identified as [3′-(aminocarbonyl)(1,1′-biphenyl)-3-yl]-cyclohexylcarbamate (URB597, 5) by comparing analytical data with that of the authentic compound. For quantitation of these three compounds, each commercial product was extracted with methanol under ultrasonication to prepare the solution for analysis by liquid chromatography with ultraviolet detection. The occurrence of compounds 1 and 2, and AM-1220 (3) and its azepane isomer (4) in 29 commercial products found in the Tokyo area are also shown in this report.     

Identification of (1<Emphasis Type="Italic">H</Emphasis>-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone (DP-UR-144) in a herbal drug product that was commercially available in the Tokyo metropolitan area

We encountered during our investigation a case of herbal drug products commercially available in the Tokyo metropolitan area in 2014, in which a small unknown peak was detected, along with the intense peak of FUB-144, by liquid chromatography–ultraviolet detection. The present study was conducted to identify and clarify the pharmacological characteristics of the compound present in this small peak. We isolated a compound using a silica gel column from the peak, which was then identified to have a molecular weight of 241 Da by liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry. The accurate mass measurement suggested an elementary composition of C₁₆H₁₉NO. Using these mass data together with those obtained by the nuclear magnetic resonance analysis, the compound was finally identified as (1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone (despentyl-UR-144; DP-UR-144). In addition, this compound was revealed to have affinities for cannabinoid receptors CB₁ and CB₂ with EC₅₀s of 2.36 × 10^?6 and 2.79 × 10^?8 M, respectively. To our knowledge, there is no information in the scientific literature on structural or pharmacological properties of this chemical. These results suggest that the components present in small amounts can contribute to the effects of a major component in their mother product, if they have sufficient pharmacological activities, and, therefore, even such small amounts of components should be precisely characterized and well evaluated to control illegal and potentially illegal drug products.     

Human urinary metabolite pattern of a new synthetic cannabimimetic,methyl 2-(1-(cyclohexylmethyl)-1<Emphasis Type="Italic">H</Emphasis>-indole-3-carboxamido)-3,3-dimethylbutanoate

A number of metabolites of a new synthetic cannabimimetic, which is a derivative of 2-(1-(cyclohexylmethyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoic acid, were identified in human urine. The parent compound, a methyl ester of this acid, was identified in seizures in persons from the same city where analysis of drug-intoxication urine samples revealed the presence of the compound’s metabolites. This compound named ‘MDMB-CHMICA’ was reported to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) via the Early Warning System (EWS) in 2014. Hydrolysis of the ester was found to be the main metabolic pathway followed by mono-, di- and tri-hydroxylation, ketone formation, ketone formation with monohydroxylation, dealkylation, and dealkylation combined with hydroxylation. Additionally, the products by internal dehydration of hydroxylated forms with lactone formation were detected. Mono-hydroxylated metabolites were detected from their glucuronidated forms. Identification of metabolites was made on the basis of gas chromatography–mass spectrometry and liquid chromatography with time-of-flight mass spectrometry and ion trap mass spectrometry. To our knowledge, this is the first report on the metabolites of MBDB-CHMICA in human urine.