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 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 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.     

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 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.     

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 a cannabimimetic indole as a designer drug in a herbal product

A cannabimimetic indole has been identified as a new adulterant in a herbal product being sold illegally in Japan for its expected narcotic effect. Liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analyses indicated that the product contained two major compounds. One was identified as a cannabinoid analog (1RS,3SR)-3-[4-(1,1-dimethyloctyl)-2-hydroxyphenyl]cyclohexan-1-ol (1) by direct comparison with the authentic compound, which we reported previously. The other compound (2) showed a molecular weight of 341 daltons, and accurate mass spectral measurements showed its elemental composition to be C₂₄H₂₃NO. Both mass and nuclear magnetic resonance spectrometric data revealed that 2 was 1-pentyl-3-(1-naphthoyl)indole [or naphthalen-1-yl-(1-pentylindol-3-yl)methanone] being identical to JWH-018, which was synthesized by Wiley and coworkers in 1998. This compound was reported as a potent cannabinoid receptor agonist possessing a pharmacological cannabimimetic activity.     

[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.     

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.     

Simultaneous determination of tryptamine analogues in designer drugs using gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry

In recent years, a large number of tryptamine-based designer drugs have been encountered in forensic samples. We have developed simultaneous analytical methods for 14 tryptamine analogues using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS). Trimethylsilyl (TMS) derivatives of the analytes were separated on a DB-1ms column within 15 min. The structural isomers could be differentiated by electron ionization GC–MS. LC–MS–MS with a C₁₈ column could separate structural isomers of tryptamines except for a combination of 5-methoxy-N,N-diethyltryptamine and 5-methoxy-N-methyl-N-isopropyltryptamine. Higher collision energy gave different product ion spectra between the structural isomers. The results indicate that GC–MS is the first choice for identification of tryptamines, preferably after TMS derivatization, and LC–MS–MS can be used as a complementary approach for the unequivocal differentiation of tryptamine isomers.     

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 of the synthetic cannabinoid <Emphasis Type="Italic">N</Emphasis>-(2-phenyl-propan-2-yl)-1-(4-cyanobutyl)-1<Emphasis Type="Italic">H</Emphasis>-indazole-3-carboxamide (CUMYL-4CN-BINACA) in a herbal mixture product

We were the first to detect N-(2-phenylpropan-2-yl)-1-(4-cyanobutyl)-1H-indazole-3-carboxamide (common name CUMYL-4CN-BINACA) as a new synthetic cannabinoid, on the illegal market in Bursa, Turkey. To elucidate the chemical structure, the dried herbal mixture was extracted with methanol. The extract was purified by column chromatography. Pure compound was analyzed by gas chromatography–mass spectrometry (GC–MS), attenuated total reflection Fourier-transform infrared spectroscopy (FT-IR), and one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. The GC–MS, FT-IR and ¹H and ¹³C NMR spectra of the compound coincided well with the reference data. All protons and carbons were assigned by their couplings and correlations observed in ¹H-¹H correlation spectroscopy, ¹H-¹³C heteronuclear multiple bond correlation, and ¹H-¹³C heteronuclear single quantum coherence spectra. On the basis of the spectral data, the compound was identified as CUMYL-4CN-BINACA. Herewith, we report analytical characteristics of CUMYL-4CN-BINACA enabling its (and possible analogues thereof) determination in criminal seizures.     

In vivo metabolism of the new synthetic cannabinoid APINAC in rats by GC–MS and LC–QTOF-MS

The recent appearance of APINAC (AKB-57, ACBL(N)-018, adamantan-1-yl 1-pentyl-1H-indazole-3-carboxylate) in the market of the so-called novel psychoactive substances resulted in the need of defining its characteristics and searching its metabolites for subsequent detection in biological samples. The structure of the APINAC molecule has great similarity to the molecules of other synthetic cannabinoids. Here we report on the in vivo metabolism of APINAC using rats as an experimental model. Rat urine samples were analyzed by using gas chromatography–mass spectrometry and liquid chromatography–high resolution mass spectrometry. Data were acquired via time-of-flight mass scan, followed by Auto MS and triggered product ion scans. The predominant metabolic pathway for APINAC was ester hydrolysis yielding a wide variety of N-pentylindazole-3-carboxylic acid metabolites and 1-adamantanol metabolites. Ten metabolites for APINAC were identified, with the majority generated by hydroxylation, carbonylation, and carboxylation with or without glucuronidation. Therefore, in vivo metabolic profiles in rats were generated for APINAC. N-Pentylindazole-3-carboxylic acid, hydroxylated N-pentylindazole-3-carboxylic acid, and 1-adamantanol are likely the best targets to incorporate into analytical screening methods for drugs analysis. The presented mass spectra and retention time data may be useful for detection of these compounds in human urine.     

Thermal degradation of a new synthetic cannabinoid QUPIC during analysis by gas chromatography–mass spectrometry

Quinolin-8-yl 1-pentyl-(1H-indole)-3-carboxylate (QUPIC) is a newly introduced synthetic cannabinoid in the drug market. This drug was found to undergo thermal decomposition during gas chromatography–mass spectrometry (GC–MS), probably because of the presence of an ester bond in its structure. Most notably, when QUPIC dissolved in methanol or ethanol was analyzed by GC–MS, most of the QUPIC decomposed to give thermal degradation products. We identified the products as methyl 1-pentyl-(1H-indole)-3-carboxylate, ethyl 1-pentyl-(1H-indole)-3-carboxylate, and methyl indole-3-carboxylate by comparison of their mass spectra with those of reference standards synthesized in our laboratory. Nonalcoholic solvents such as acetone and chloroform gave a major peak and a minor peak for unchanged QUPIC and the degradation product 8-quinolinol, respectively. Furthermore, we studied the effects of various parameters, such as injection methods (splitless or split, and split ratio), injector temperatures, and injector liners on the thermal degradation of QUPIC. Split injection was effective in avoiding degradation. When performing splitless injection, an injector temperature of 250 °C and a surface deactivated injector liner without glass wool minimized the degradation and enhanced the sensitivity. These results indicate that special attention is required for GC–MS analysis of QUPIC, and the information presented in this study will be very useful for forensic toxicologists using GC–MS.     

Two new synthetic cannabinoids, AM-2201 benzimidazole analog (FUBIMINA) and (4-methylpiperazin-1-yl)(1-pentyl-1H-indol-3-yl)methanone (MEPIRAPIM), and three phenethylamine derivatives, 25H-NBOMe 3,4,5-trimethoxybenzyl analog, 25B-NBOMe, and 2C-N-NBOMe, identified in illegal products

Two new types of synthetic cannabinoids, an AM-2201 benzimidazole analog (FUBIMINA, 1) and (4-methylpiperazin-1-yl)(1-pentyl-1H-indol-3-yl)methanone (MEPIRAPIM, 2), and three newly emerged phenethylamine derivatives, 25B-NBOMe (3), 2C-N-NBOMe (4), and a 25H-NBOMe 3,4,5-trimethoxybenzyl analog (5), were detected in illegal products distributed in Japan. The identification was based on liquid chromatography–mass spectrometry (LC–MS) and gas chromatography–mass spectrometry (GC–MS), high-resolution MS, and nuclear magnetic resonance analyses. Different from the representative synthetic cannabinoids, such as JWH-018, which have a naphthoylindole moiety, compounds 1 and 2 were completely new types of synthetic cannabinoids; compound 1 had a benzimidazole group in place of an indole group, and compound 2 had a 4-methylpiperazine group in place of the naphthyl group. Compounds 3 and 4 were N-o-methoxybenzyl derivatives of 2,5-dimethoxyphenethylamines (25-NBOMe series), which had been previously detected in European countries, but have newly emerged in Japan. Compound 5 had an N-trimethoxybenzyl group in place of an N-o-methoxybenzyl group. Data on the chemistry and pharmacology of compounds 1, 2, and 5 have never been reported to our knowledge.     

Identification of N-ethyl-α-ethylphenethylamine in crystalline powder seized for suspected drug trafficking: a research chemical or a new designer drug?

A crystalline powder was found in an unclaimed lost article shipped from Vietnam to South Korea, and it was seized by narcotics agents as an item of suspicious trade. The chemical was suspected to be methamphetamine crystals, and was sent to the National Forensic Service for forensic identification. Elucidation of the chemical structure was carried out using gas chromatography–electron impact ionization–mass spectrometry, liquid chromatography–time-of-flight–mass spectrometry, and 1D and 2D nuclear magnetic resonance spectroscopy. The compound was identified as N-ethyl-α-ethylphenethylamine. Although the narcotic effect of this compound remains unverified, it may be classified as a phenethylamine-based designer drug on the basis of its structure. It appeared that the recipient of this article sought to abuse this chemical in the same way as amphetamines. There is a possibility that this chemical will be widely abused for recreational use in the near future.     

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.     

Differentiation of AB-FUBINACA and its five positional isomers using liquid chromatography–electrospray ionization-linear ion trap mass spectrometry and triple quadrupole mass spectrometry

Purpose

Positional isomer differentiation is crucial for forensic analysis. The aim of this study was to differentiate AB-FUBINACA positional isomers using liquid chromatography (LC)–electrospray ionization (ESI)-linear ion trap mass spectrometry (LIT-MS) and LC–ESI-triple quadrupole mass spectrometry (QqQ-MS).

Methods

AB-FUBINACA, its two fluorine positional isomers on the phenyl ring, and three methyl positional isomers in the carboxamide side chain were analyzed by LC–ESI-LIT-MS and LC–ESI-QqQ-MS.

Results

Four of the positional isomers, excluding AB-FUBINACA and its 3-fluorobenzyl isomer, were chromatographically separated on an ODS column in isocratic mode. ESI-LIT-MS could discriminate only three isomers, i.e., the 2-fluorobenzyl isomer, the N-(1-amino-2-methyl-1-oxobutan-2-yl) isomer, and the N-(1-amino-1-oxobutan-2-yl)-N-methyl isomer, based on their characteristic product ions observed at the MS³ stage in negative mode. ESI-QqQ-MS differentiated all six isomers in terms of the relative abundances of the product ions that contained the isomeric moieties involved in collision-induced dissociation reactions. The six isomers were more clearly and significantly differentiated upon comparison of the logarithmic values of the product ion abundance ratios as a function of collision energy.

Conclusions

The present LC–MS methodologies were useful for the differentiation of a series of AB-FUBINACA positional isomers.

     

Sensitive identification and quantitation of parent forms of six synthetic cannabinoids in urine samples of human cadavers by liquid chromatography–tandem mass spectrometry

Human urine samples are easier to obtain than human blood samples due to noninvasiveness. The urine levels of synthetic cannabinoids (SCs) in unchanged forms, however, are usually much lower than their blood and tissue levels and cannot be detected in most cases. Therefore, in the present work a sensitive analytical method was devised for the determination of urine levels of six SCs in unchanged forms such as N-(1-amino-3-methy-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide (AB-PINACA), N-(1-amino-3-methy-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA), N-[(1S)-1-(1-aminocarbonyl)-2-methyl-propyl]-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (AB-CHMINACA), N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (MAB-CHMINACA), methyl-2-[1-(5-fluoropentyl)-1H-indazole-3-carboxamido]-3-methylbutanoate (5F-AMB) and methyl-2-[1-(5-fluoropentyl)-1H-indazole-3-carboxamido]-3,3-dimethylbutanoate (5F-ADB). These SCs were extracted from urine via liquid–liquid extraction. The identification and quantitation were performed by a relatively new type of an instrument for liquid chromatography–tandem mass spectrometry. The limits of detection were as low as 3–8 pg/mL, and the quantitation range was 10–1000 pg/mL using 400 μL of urine. The urine levels of AB-PINACA and AB-FUBINACA of victim 1 were 23 and 10 pg/mL, those of AB-CHMINACA and 5F-AMB of victim 2 were 239 and 19 pg/mL, and those of MAB-CHMINACA and 5F-ADB of victim 3 were 229 and 19 pg/mL, respectively. To our knowledge, this is the first report dealing with successful analysis of low levels of parent synthetic cannabinoids in authentic human urine specimens.     

A fast chemoenzymatic synthesis of [11C]-N5,N10-methylenetetrahydrofolate as a potential PET tracer for proliferating cells

IntroductionThymidylate synthase and folate receptors are well-developed targets of cancer therapy. Discovery of a simple and fast method for the conversion of ¹¹CH₃Ito[¹¹C]-formaldehyde (¹¹CH₂O) encouraged us to label the co-factor of this enzyme. Preliminary studies conducted on cell lines have demonstrated a preferential uptake of [11-¹⁴C]-(R)-N⁵,N¹⁰-methylene-5,6,7,8-tetrahydrofolate (¹⁴CH₂H₄folate) by cancerous cell vs. normal cells from the same organ (Saeed M., Sheff D. and Kohen A. Novel positron emission tomography tracer distinguishes normal from cancerous cells. J Biol Chem 2011;286:33872–33878), pointing out ¹¹CH₂H₄folate as a positron emission tomography (PET) tracer for cancer imaging. Herein we report the synthesis of ¹¹CH₂H₄folate, which may serve as a potential PET tracer.MethodsIn a remotely controlled module, methyl iodide (¹¹CH₃I) was bubbled into a reaction vial containing trimethylamine N-oxide in N,N-Dimethylformamide (DMF) and heated to 70°C for 2 min. Formaldehyde (¹¹CH₂O) formed after the completion of reaction was then mixed with a solution of freshly prepared tetrahydrofolate (H₄folate) by using a fast chemoenzymatic approach to accomplish synthesis of ¹¹CH₂H₄folate. Purification of the product was carried out by loading the crude reaction mixture on a SAX cartridge, washing with water to remove unbound impurities and finally eluting with a saline solution.ResultsThe synthesis and purification of ¹¹CH₂H₄folate were completed within 5 min. High-performance liquid chromatography analysis of the product after SAX purification indicates that more than 90% of the radioactivity that was retained on the SAX cartridge was in ¹¹CH₂H₄folate, with minor (<10%) radioactivity due to unreacted ¹¹CH₂O.ConclusionWe present a fast (～5 min) synthesis and purification of ¹¹CH₂H₄folate as a potential PET tracer. The final product is received in physiologically compatible buffer (100 mM sodium phosphate, pH 7.0 containing 500 mM NaCl) and ready for use in vivo.