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The abuse of amphetamine-type stimulants (ATSs) has caused irreversible harm to public safety and ecosystems. A novel polymerized deep eutectic solvent modified magnetic pomelo peel biochar (PMBC) was prepared, and the differences in adsorption of four abused amphetamine-type stimulants (ATSs: AMP, MAMP, MDA and MDMA) were due to varying hydrogen bonds quantities and strengths. PMBC showed excellent chemical reactivity to MDMA, with a maximum adsorption capacity of 926.13 μg g -1 , which was 3.25, 2.52 and 1.15 times higher than that of AMP, MAMP and MDA, respectively. Modern spectral analysis showed that there were a series of active centers (-COOH, -NH 2 and -OH) on the PMBC, which could form hydrogen bond networks with the nitrogen and oxygen functional groups of ATSs. In various chemical environments: pH level (4-11), inorganic ion and organic matter (humic acid), PMBC maintained high activity towards four ATSs. Additionally, the quantum chemical calculations revealed that the methylenedioxy bridge of ATSs can increase the active sites, and the -NH- and -NH 2 groups had different hydrogen bond formation capabilities, which together resulted in the adsorption order of PMBC on the four ATSs: MDMA > MDA > MAMP > AMP. Moreover, the hydrogen-bonding binding energies of several common hydrogen-bonding types were compared, including O-H····O, N-H····O/O-H····N and N-H···N. This study laid an empirical and theoretical foundation for the efficient capture of ATSs in water and contributed to the innovative design of materials., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shurui Cao reports financial support was provided by Chongqing Municipal Education Commission. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier Inc. All rights reserved.)

In this research, a variety of novel amphetamine derivatives were synthesized and assessed for their potential as multifaceted antidepressant agents. Among these compounds, compound 11b demonstrated potent inhibitory effects on both serotonin and noradrenaline transporters (SERT/NET) and high affinity for histamine H 3 receptor (H 3 R), and displayed low affinity for off-target receptors (H1, α1) and hERG channels, which can reduce the prolongation of the QT interval. Molecular docking studies offered a rational binding model of compound 11b when it forms a complex with SERT, NET, and the histamine H 3 receptor. In vivo behavioral studies, compound 11b dose-dependently reduced the immobility duration in the mouse FST and TST assays without a stimulatory effect on the locomotor activity. Furthermore, compound 11b had a favorable pharmacokinetic profile in rats. Thus, compound 11b has the potential to develop a novel class of drugs for the treatment of depression.

Less steric ketones exhibited low stereoselectivity toward M5 due to their difficulty in restricting the free rotation of the imine intermediate. An engineered enantio-complementary imine reductase from M5 was obtained with catalytic activity. We identified four key residues that play essential roles in controlling stereoselectivity. Two mutants, I149Y-W234L (up to 99% S ee ) and L200M-F260M (up to 99% R ee ), were achieved, showing excellent stereoselectivity toward the tested substrates, offering valuable biocatalysts for synthesizing alkylated amphetamines.

Magnetic surface imprinted polymer microspheres (Fe 3 O 4 @MIPs) were successfully synthesized via Pickering emulsion polymerization, utilizing N-Methylphenethylamine as a surrogate template for amphetamine-type drugs. Fe 3 O 4 @MIPs not only possessed excellent dispersibility and enough magnetic properties in aqueous solutions, but also displayed good selectivity towards six amphetamines, with an imprinting factor ranging from 1.8 to 2.6. The adsorption kinetics closely aligned with the pseudo-second-order model, and the adsorption efficiency exceeds 80 % for each amphetamine at equilibrium. Fe 3 O 4 @MIPs were then employed as the efficient adsorbents for the extraction of amphetamine drugs. Extraction parameters, including sample pH, the mass of adsorbent, and the type and volume of eluting solvent, were carefully optimized. In combination with the high performance liquid chromatography tandem triple quadrupole mass spectrometry (HPLC-MS/MS), a selective magnetic solid-phase extraction (MISPE) method utilizing Fe 3 O 4 @MIPs was developed for the detection of six amphetamines in water samples. The limits of detection and limits of quantitation were determined to be 5.2∼23 ng L -1 and 17∼77 ng L -1 , respectively. Recoveries for the six target drugs from lake water and sewage samples fell within the range of 87.2∼110 %. Additionally, the MISPE-HPLC-MS/MS method exhibited excellent repeatability, with a precision below 8.5 % at two spiking levels. The prepared Fe 3 O 4 @MIPs possessed the advantages of high selectivity, straightforward preparation, facile separation and good reusability, and was highly suitable for the efficient extraction of amphetamine-type substances in complex environmental water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The use of controlled precursors for reaction optimisation is not always practical. One approach to limiting the use of controlled substances is to instead use 'model compounds'. Herein, two model compounds resembling norephedrine and ephedrine were selected based on their (i) structural similarity (i.e., presence of key functional groups) and (ii) availability from multiple suppliers without restriction. Model compounds 2-amino-1-phenylethanol and 2-(methylamino)-1-phenylethanol (halostachine), were compared to norephedrine and pseudoephedrine by firstly subjecting them to transformations known in the synthesis of amphetamines, and secondly, comparing the compounds using colourimetric spot tests, FTIR and NMR., Competing Interests: Declaration of Competing Interest none, (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)

Herein, the capture and separation properties of the deep eutectic solvent-functionalized magnetic graphene oxide/ZIF-67 composite (ZMG-DES) towards amphetamine-type drugs (MDMA, MAM and AM) from water were investigated. Kinetic and isotherm models showed that the adsorption behaviors were monolayer chemisorption. Batch experiment results showed that the maximal adsorption of MDMA (933.652 μg⋅g -1 ) was 2.3 and 2.8 times higher than that of MAM (412.849 μg⋅g -1 ) and AM (328.652 μg⋅g -1 ), respectively, and this superiority remained consistent under varied environmental influences (pH, background ion and humic acid). Theoretical calculations and characterization analyses demonstrated the methylenedioxy group of MDMA led to the highly selective adsorption. Electrostatic potential (ESP) distribution indicated that the methylenedioxy added electron-rich areas and provided more adsorption sites. The Independent Gradient Model (IGMH) quantified the adsorption contribution of the functional groups in each system, which the contribution of the methylenedioxy reached 25.23%, significantly exceeding that of -NH- (18.80%) and benzene ring (20.76%), and proved that the H-bonds formed methylenedioxy enhanced adsorption. Furthermore, the Hirshfeld surface analysis proved that the methylenedioxy and -NH- of MDMA acted as H-bond acceptor and donor, respectively, which synergistically promoted the adsorption. The present study will help us to understand the structure-property relationship between amphetamine-type drugs and ZMG-DES., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Among different substance classes, New Psychoactive Substances (NPS) comprise chiral amphetamines for stimulant and empathic effects. There is little knowledge in terms of clinical studies about possibly different effects of the two enantiomers of novel amphetamine derivatives. For this reason, there is a big demand for enantioseparation method development of this new substance class. Regarding gas chromatography, cyclodextrins proved to be effective for enantioseparation of NPS. In our attempt, an Astec® Chiraldex™ G-PN column containing 2,6-di-O-pentyl-3-propionyl-γ-cyclodextrin and a Lipodex™ D column containing heptakis-(2,6-di-O-pentyl-O-acetyl)-β-cyclodextrin as chiral selector served as stationary phases in a Shimadzu GCMS-QP2010 SE system. Because of the special coating, maximum temperature is limited to 200 °C isothermal or 220 °C in programmed mode. To ensure detection, trifluoroacetic anhydride (TFAA) was used to increase sample volatility. 1 As a result, 35 amphetamines were tested as their TFAA-derivatives. A screening method with a temperature gradient from 140 °C to 200 °C at a heating ramp of 1 °C per minute and final time of 5 min, showed baseline separation for seven and partial separations for 16 trifluoro acetylated amphetamines using the Chiraldex™ G-PN column. Six baseline and nine partial separations were observed with the Lipodex™ D column, respectively., (© 2024 The Authors. Chirality published by Wiley Periodicals LLC.)

The vaporization enthalpy, and vapor pressure as a function of temperature of N -ethylamphetamine, a substance used in the 1950s as an appetite suppressant and more currently abused as a designer drug, is reported. Its physical properties are compared to those of S (+)- N -methamphetamine, a substance whose physiological properties it mimics. A vaporization enthalpy of (62.4 ± 4.4) kJ·mol -1 and vapor pressure of (19 ± 11) Pa at T = 298.15 K has been evaluated by correlation gas chromatography. Results are compared to estimated values and to the limited amount of experimental property data available.

Amphetamine-based (Amph) drugs are metabolized in humans to their hydroxylamine (AmphNHOH) and nitroso (AmphNO) derivatives. The latter metabolites are known to bind to the Fe centers of cytochrome P450 and other heme enzymes to inhibit their activities. Although these AmphNHOH/AmphNO metabolites are present in vivo, their interactions with the blood protein hemoglobin (Hb) and the muscle protein (Mb) have been largely discounted due to a perception that the relatively small heme active sites of Hb and Mb will not be able to accommodate the large AmphNO group. We report the 2.15 Å resolution X-ray crystal structure of the AmphNO adduct of adult human hemoglobin as the Hb [α-Fe III (H 2 O)][β-Fe II (AmphNO)] derivative. We show that the binding of AmphNO to the β subunit is enabled by an E helix movement and stabilization of ligand binding by H-bonding with the distal His63 residue. We also observe an AmphNHOH group in the Xe2 pocket in close proximity to the α heme site in this derivative. Additionally, UV-vis spectroscopy was used to characterize this and related wt and mutant Mb adducts. Importantly, our X-ray crystal structure of this Hb-nitrosoamphetamine complex represents the first crystal structure of a wild-type heme protein adduct of any amphetamine metabolite. Our results provide a framework for further studies of AmphNHOH/AmphNO interactions with Hb and Mb as viable processes that potentially contribute to the overall biological inorganic chemistry of amphetamine drugs., (Published by Elsevier Inc.)

Amphetamine derivatives have been used in a wide variety of pathologies because of their pharmacological properties as psychostimulants, entactogens, anorectics, and antidepressants. However, adverse cardiovascular effects (sympathomimetics) and substance abuse problems (psychotropic and hallucinogenic effects) have limited their use. 4-Methylthioamphetamine (MTA) is an amphetamine derivative that has shown to inhibit monoamine uptake and monoamine oxidase. However, the pharmacological characterization (neurochemical, behavioral, and safety) of its derivatives 4-ethylthioamphetamine (ETA) and 4-methylthio-phenil-2-butanamine (MT-But) have not been studied. In the current experiments, we show that ETA and MT-But do not increase locomotor activity and conditioned place preference with respect to MTA. At the neurochemical level, ETA and MT-But do not increase in vivo DA release in striatum, but ETA and MT-But affect the nucleus accumbens bioaccumulation of DA and DOPAC. Regarding cardiovascular effects, the administration of MTA and ETA increased the mean arterial pressure and only ETA significantly increases the heart rate. Our results show that the pharmacological and safety profiles of MTA are modulated by changing the methyl-thio group or the methyl group of the aminoethyl chain.

Interpretation of amphetamine-type stimulant (ATS) findings in urine samples can be challenging without chiral information. We present a sensitive enantioselective high-performance liquid chromatography-tandem mass spectrometry method for the quantification of (R)-amphetamine, (S)-amphetamine, (R)-methamphetamine, (S)-methamphetamine, (1R,2R)-pseudoephedrine, (1S,2S)-pseudoephedrine, (1R,2S)-ephedrine, (1S,2R)-ephedrine, (1R,2S)-norephedrine, (1S,2R)-norephedrine, (R)-cathinone, (S)-cathinone, and (1S,2S)-norpseudoephedrine (cathine) in urine. The method was successfully applied to more than 100 authentic urine samples from forensic casework. In addition, samples from a controlled self-administration of (1S,2S)-pseudoephedrine (Rinoral, 1200 mg within 6 days) were analyzed. The results strengthen the hypothesis that (1R,2S)-norephedrine is a minor metabolite of amphetamine and methamphetamine. We suggest cathine and (1S,2R)-norephedrine as minor metabolites of amphetamine racemate in humans. Small methamphetamine concentrations detected in samples with high concentrations of amphetamine could result from a metabolic formation by methylation of amphetamine although in samples with an (R)/(S) ratio for methamphetamine < 1 an additional (previous) (S)-methamphetamine consumption seems likely. Our data suggest that even amphetamine concentrations exceeding methamphetamine concentrations in urine can be caused by the biotransformation of methamphetamine to amphetamine as long as no (R)-amphetamine is detected. However, without chiral information, such findings might be (falsely) assumed as a co-consumption of both substances. Cathinone enantiomers detected in urine samples with high amphetamine concentrations can be interpreted as metabolites of amphetamine. In addition, the results of the self-administration study revealed that both cathinone enantiomers are minor metabolites of (1S,2S)-pseudoephedrine, which is the active ingredient of various medicines used for cold. The enantioselective analysis is a powerful tool to avoid the misinterpretation of ATS findings in urine samples., (© 2020 The Authors. Drug Testing and Analysis published by John Wiley & Sons Ltd.)

A simple and rapid pipette-tip solid-phase extraction (PT-SPE) procedure with derivatization prior to gas chromatography triple quadrupole mass spectrometry analysis is developed for the simultaneous determination of amphetamine (AMP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) in urine samples. The PT-SPE procedure using self-made sorbent could extract drugs within 6 min from 100-μL urine samples, requiring low solvent-consumption (<2.0 mL). Besides, the self-made pipette tip could be reused at least five times. Under optimized conditions, the recoveries of four amphetamines at spiked levels (low, medium and high) ranged from 87.7 to 110.4%, with relative standard deviations < 9.5%. The limit of detections and limit of quantifications for AMP, MA, MDA and MDMA were in the range of 2.52-8.25 ng⋅mL-1 and 8.4-27.5 ng⋅mL-1, respectively. Validation results show that the proposed method is suitable for the quantitation of amphetamines and has been successfully applied in the urine samples of suspected drug abusers., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Increasing reports of neurological and psychiatric complications due to psychostimulant synthetic cathinones (SCs) have recently raised public concern. However, the precise mechanism of SC toxicity is unclear. This paucity of understanding highlights the need to investigate the in-vitro toxicity and mechanistic pathways of three SCs: butylone, pentylone, and 3,4-Methylenedioxypyrovalerone (MDPV). Human neuronal cells of SH-SY5Y were cultured in supplemented DMEM/F12 media and differentiated to a neuronal phenotype using retinoic acid (10 μM) and 12- O -tetradecanoylphorbol-13-acetate (81 nM). Trypan blue and lactate dehydrogenase assays were utilized to assess the neurotoxicity potential and potency of these three SCs. To investigate the underlying neurotoxicity mechanisms, measurements included markers of oxidative stress, mitochondrial bioenergetics, and intracellular calcium (Ca 2+ ), and cell death pathways were evaluated at two doses (EC 15 and EC 40 ), for each drug tested. Following 24 h of treatment, all three SCs exhibited a dose-dependent neurotoxicity, characterized by a significant ( p < 0.0001 vs. control) production of reactive oxygen species, decreased mitochondrial bioenergetics, and increased intracellular Ca 2+ concentrations. The activation of caspases 3 and 7 implicated the orchestration of mitochondrial-mediated neurotoxicity mechanisms for these SCs. Identifying novel therapeutic agents to enhance an altered mitochondrial function may help in the treatment of acute-neurological complications arising from the illicit use of these SCs., Competing Interests: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Here, we present a fully validated method using a hollow-fibre liquid-phase microextraction technique for the determination by gas chromatography-mass spectrometry (GC-MS) of amphetamine (AMP), methamphetamine (MET), fenproporex (FEN), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxyethylamphetamine (MDEA) in whole blood. The validation parameters presented successful values within those recommended by the Scientific Working Group for Forensic Toxicology (SWGTox) in the Standard Practices for Method Validation in Forensic Toxicology. The limits of detection ranged from 1 to 3 ng/mL, and the limits of quantification ranged from 2 to 5 ng/mL. The determination coefficients (r 2 ) ranged from 0.990 to 0.997, and the method presented good intraday and interday accuracy (from 90.4% to 97.2%) and satisfactory recovery (from 68% to 110%). No carryover was observed. The heteroscedasticity was tested, and only AMP presented homoscedasticity. Weighting factors were applied to correct the linearity of MET (1/x 2 ), MDA (1/x), FEN (1/x 1/2 ), MDMA (1/x 2 ) and MDEA (1/y). Dilution integrity was tested at ratios of 1:2, 1:5 and 1:10, and all maintained intraday precision (from 94.9% to 99.3%) and interday precision (from 89.4% to 94.9%). The validated method was applied to six real whole blood samples from individuals suspected of consuming ecstasy, and MDMA, MDA and amphetamine were successfully identified and quantified., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

3-Fluoroamphetamine (also called PAL-353) is a synthetic amphetamine analog that has been investigated for cocaine use disorder (CUD), yet no studies have characterized its pharmacokinetics (PK). In the present study, we determined the PK of PAL-353 in male Sprague Dawley rats following intravenous bolus injection (5 mg/kg). Plasma samples were analyzed using a novel bioanalytical method that coupled liquid-liquid extraction and LC-MS/MS. The primary PK parameters determined by WinNonlin were a C 0 (ng/mL) of 1412.09 ± 196.12 and a plasma half-life of 2.27 ± 0.67 h. As transdermal delivery may be an optimal approach to delivering PAL-353 for CUD, we assessed its PK profile following application of 50 mg of transdermal gel (10% w/w drug over 5 cm 2 ). The 10% w/w gel resulted in a short lag time, sustained delivery, and a rapid clearance in plasma immediately after removal. The rodent PK data were verified by examining in vitro permeation through human epidermis mounted on Franz diffusion cells. An in vitro-in vivo correlation (IVIVC) analysis was performed using the Phoenix IVIVC toolkit to assess the predictive relationship between rodent and human skin absorption/permeation. The in vitro permeation study revealed a dose-proportional cumulative and steady-state flux with ~ 70% of drug permeated. The fraction absorbed in vivo and fraction permeated in vitro showed a linear relationship. In conclusion, we have characterized the PK profile of PAL-353, demonstrated that it has favorable PK properties for transdermal administration for CUD, and provided preliminary evidence of the capacity of rodent data to predict human skin flux.

The pre-precursor market and the clandestine production of amphetamine-type stimulants (ATS) has become more diverse in recent years. Besides α-phenylacetoacetonitrile (APAAN) and α-phenylacetoacetamide (APAA), glycidic acid derivatives and methyl α-phenylacetoacetate (MAPA) are gaining importance. This conclusion is based on seizure data of police and customs. However, analytical data are needed to confirm and quantify the actual prevalence of new pre-precursors by elucidating the percentage of seized ATS that have been produced from them. A recent study showed that APAAN use is currently declining, which supports the view that new pre-precursors are being used. In this study, several conversion procedures using different batches of glycidic acid derivatives and a complete Leuckart reaction to produce amphetamine were carried out. The resulting organic phases were analyzed using gas chromatography - mass spectrometry to identify possible marker compounds. Three marker compounds were discovered and characterized using mass spectra and nuclear magnetic resonance spectroscopy. They were identified as phenyl-1-propanone, N-(1-phenylpropyl)formamide and 1-phenylpropan-1-amine. Their prevalence was investigated by searching the markers in an amphetamine impurity profiling database to determine to what extent they occurred in amphetamine samples from recent years. Data from the central German amphetamine profiling database of more than 250 cases were used for this purpose. The yearly occurrence of the three glycidate marker compounds was determined going back as far as 2009, revealing an increasing trend from 2016 on. This article presents experimental proof that APAAN is currently being replaced by other pre-precursors, such as glycidic acid derivatives., (© 2019 John Wiley & Sons, Ltd.)

Synthetic cathinones also known as β-keto amphetamines are a new group of recreational designer drugs. We aimed to evaluate the cytotoxic potential of thirteen cathinones lacking the methylenedioxy ring and establish a putative structure-toxicity profile using differentiated SH-SY5Y cells, as well as to compare their toxicity to that of amphetamine (AMPH) and methamphetamine (METH). Cytotoxicity assays [mitochondrial 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) reduction and lysosomal neutral red (NR) uptake] performed after a 24-h or a 48-h exposure revealed for all tested drugs a concentration-dependent toxicity. The rank order regarding the concentration that promoted 50 % of toxicity, at 24 h exposure, by the MTT assay was: 3,4-dimethylmethcathinone (3,4-DMMC) > METH > mephedrone ≈ α-pyrrolidinopentiophenone > AMPH ≈ methedrone > pentedrone > buphedrone ≈ flephedrone >α-pyrrolidinobutiophenone > methcathinone ≈ N-ethylcathinone >α-pyrrolidinopropiophenone >N,N-dimethylcathinone ≈ amfepramone. Apoptotic cell death signs were seen for all studied cathinones. 3,4-DMMC, methcathinone and pentedrone triggered autophagy activation, as well as increased reactive oxygen species production, and N-acetyl-L-cysteine (NAC) totally prevented that rise. Importantly, NAC was also able to prevent the cytotoxicity promoted by 6 tested drugs, ruling for an involvement of oxidative stress in the toxic events observed. The increased lipophilic chain on the alpha carbon, the presence and the high steric volume occupied by the substituents on the aromatic ring, and the substitution of the pyrrolidine ring by its secondary amine analogue have proved to be key points for the cytotoxicity profile of these cathinones. The structure-toxicity relationship established herein may enlighten future human relevant mechanistic studies, and future clinical approaches on intoxications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Here, we demonstrate a supramolecular latching tool for bio-orthogonal noncovalent anchoring of small synthetic molecules in live animal models using a fully synthetic high-affinity binding pair between cucurbit[7]uril (CB[7]) and adamantylammonium (AdA). This supramolecular latching system is small (∼1 kDa), ensuring efficient uptake into cells, tissues, and whole organisms. It is also chemically robust and resistant to enzymatic degradation and analogous to well-characterized biological systems in terms of noncovalent binding. Occurrence of fluorescence resonance energy transfer (FRET) between cyanine 3-CB[7] (Cy3-CB[7]) and boron-dipyrromethene 630/650X-AdA (BDP630/650-AdA) inside a live worm ( Caenorhabditis elegans ) indicates efficient in situ high-affinity association between AdA and CB[7] inside live animals. In addition, selective visualization of a cancer site of a live mouse upon supramolecular latching of cyanine 5-AdA (Cy5-AdA) on prelocalized CB[7]-conjugating antibody on the cancer site demonstrates the potential of this synthetic system for in vivo cancer imaging. These findings provide a fresh insight into the development of new chemical biology tools and medical therapeutic systems.

The present paper describes an original method for the online preconcentration and analysis of ring-substituted amphetamines in urine samples, used on the integration of robot-assisted hollow fiber liquid-phase microextraction (HF-LPME), high-performance liquid chromatography (HPLC), and fluorescence detection (FLD). A lab-made autosampler, actuating a 100-μL syringe and equipped with a three-way solenoid microvalve, allowed the acceptor phase to flow through and be withdrawn from the lumen fiber, enabling the automated online transference of the enriched acceptor phase for chromatographic analysis, through a six-port switching valve. The developed online HF-LPME-LC/FLD method demonstrated high analytical throughput and confidence, facilitating the efficient extraction and determination of the target analytes, with minimal solvent consumption and sample manipulation, in a straightforward way. Sample cleanup, analyte uptake, and analysis were carried out in 14.5 min. Under optimal conditions, automated online HF-LPME showed excellent linearity, precision, and trueness, obtaining intraday RSDs between 2.9 and 9.2% (n = 6) and interday RSDs between 5.3 and 9.3% (n = 6). Enrichment factors (EFs) ranged between 14.2 and 15.7, extraction recoveries (ERs) ranged between 17.7 and 19.5%, and the limits of detection (S/N = 3) were 2.0, 3.0, and 3.0 μg L -1 for MDA, MDMA, and MDEA, respectively. The method proved to be an effortless, rapid, reliable, and environment-friendly approach for the determination of drug abuse in urine samples. Graphical abstract.

Much evidence demonstrates the antinociceptive effect of magnetic fields (MFs). However, the analgesic action mechanism of the electromagnetic field (EMF) is not exactly understood. The aim of the present study was to investigate the effects of 5-HT 1 and 5-HT 2 receptor agonists (serotonin HCl and 2,5-dimethoxy-4-iodoamphetamine [DOI] hydrochloride) on EMF-induced analgesia. In total, 66 adult male Wistar albino rats with an average body mass of 225 ± 13 g were used in this study. The animals were subjected to repeated exposures of alternating 50 Hz and 5 mT EMF for 2 h a day for 15 days. Prior to analgesia tests, serotonin HCl (5-HT 1 agonist) 4 mg/kg, WAY 100635 (5-HT 1 antagonist) 0.04 mg/kg, DOI hydrochloride (5-HT 2 receptor agonist) 4 mg/kg, and SB 204741 (5-HT 2 antagonist) 0.5 mg/kg doses were injected into rats. For statistical analysis of the data, analysis of variance was used and multiple comparisons were determined by Tukey's test. Administration of serotonin HCl MF (5 mT)-exposed rats produced a significant increase in percent maximal possible effect (% MPE) as compared with EMF group (P < 0.05). On the contrary, injection of WAY 100635 to MF-exposed rats produced a significant decrease in analgesic activity (P < 0.05). Similarly, the administration of DOI hydrochloride significantly increased % MPE values as compared with the EMF group while SB 204741 reduced it (P < 0.05). In conclusion, our results suggested that serotonin 5-HT 1 and 5-HT 2 receptors play an important role in EMF-induced analgesia; however, further research studies are necessary to understand the mechanism. Bioelectromagnetics. 2019;40:319-330. © 2019 Bioelectromagnetics Society., (© 2019 Bioelectromagnetics Society.)

Background: The appearance of stimulant-class new psychoactive substances (NPS) is a frequent and significant problem in our society. Cathinone variants are often sold illegally as 3,4-methylenedioxy methamphetamine ("ecstasy") or disguised for legal sale using misleading names such as "bath salts" and carry the risk of promoting disruptive mental states, addiction, and fatal overdose. The principal targets of these recreational drugs are monoamine transporters expressed in catecholaminergic and serotonergic neurons. Some transporter ligands can be transported into cells, where they can promote a massive release of neurotransmitters through reverse transport, and others can block uptake. A ligand's dopamine vs. serotonin transporter selectivity, potency, and activity as a substrate or blocker can help elucidate the abuse liability and subjective effects of a drug., Objectives: Here, we describe the discovery, development, and validation of an emerging methodology for compound activity assessment at monoamine transporters., Key Findings: Substrates generate inward electrical currents through transporters and can depolarize the plasma membrane, whereas blockers work as a "cork in a bottle" and function as antagonists. Voltage-gated Ca 2+ channels were co-expressed with monoamine transporters in cultured cells and used to measure fluctuations of the membrane electrical potential. In this system, substrates of monoamine transporters produce reliable dose-dependent Ca 2+ signals, while blockers hinder them., Discussion: This system constitutes a novel use of voltage-gated Ca 2+ channels as biosensors for the purpose of characterizing ligand activity at monoamine transporters using fluorimetry. This approach in combination with in vivo evaluations of drugs' abuse-related effects is a powerful strategy for anticipating potential stimulant-class NPS.

Rationale: Synthetic cathinones continue to emerge in recreational drug markets worldwide. 1-(1,3-Benzodioxol-5-yl)-2-(methylamino)butan-1-one (butylone) and 1-(1,3-benzodioxol-5-yl)-2-(methylamino)pentan-1-one (pentylone) are derivatives of the cathinone compound, 1-(1,3-benzodioxol-5-yl)-2-(methylamino)propan-1-one (methylone), that are being detected in drug products and human casework., Objectives: The purpose of the present study was to examine the neuropharmacology of butylone and pentylone using in vitro and in vivo methods., Methods: In vitro uptake and release assays were carried out in rat brain synaptosomes and in cells expressing human dopamine transporters (DAT) and 5-HT transporters (SERT). In vivo microdialysis was performed in the nucleus accumbens of conscious rats to assess drug-induced changes in neurochemistry., Results: Butylone and pentylone were efficacious uptake blockers at DAT and SERT, though pentylone was more DAT-selective. Both drugs acted as transporter substrates that evoked release of [ 3 H]5-HT at SERT, while neither evoked release at DAT. Consistent with the release data, butylone and pentylone induced substrate-associated inward currents at SERT but not DAT. Administration of butylone or pentylone to rats (1 and 3 mg/kg, i.v.) increased extracellular monoamines and motor activity, but pentylone had weaker effects on 5-HT and stronger effects on motor stimulation., Conclusions: Our data demonstrate that increasing the α-carbon chain length of methylone creates "hybrid" transporter compounds which act as DAT blockers but SERT substrates. Nevertheless, butylone and pentylone elevate extracellular dopamine and stimulate motor activity, suggesting both drugs possess significant risk for abuse.

Rationale: The synthetic cathinones are a class of designer drugs of abuse that share a common core scaffold. The pharmacokinetic profiles of the synthetic cathinones vary based on the substitutions to the core scaffold., Objectives: To provide a summary of the literature regarding the pharmacokinetic characteristics of the synthetic cathinones, with a focus on the impact of the structural modifications to the pharmacokinetics., Results: In many, but not all, instances the pharmacokinetic characteristics of the synthetic cathinones can be reasonably predicted based on the substitutions to the core scaffold. Mephedrone and methylone are chemically alike and have similar T max and t 1/2 in male rats. MDPV, a structurally distinct synthetic cathinone from mephedrone and methylone, has a lower T max and t 1/2 . Increasing the length of the alkyl chain on the α position of methylone, to produce pentylone, results in increased plasma concentrations and longer t 1/2 . Metabolism of the synthetic cathinones is reasonably predictable based on the chemical structure, and several phase I metabolites retain pharmacodynamic activity. CYP2D6 is implicated in the metabolism of all of the synthetic cathinones, and other P450s (CYP1A2, CYP2B6, and CYP2C19) are known to contribute variably to the metabolism of specific synthetic cathinones., Conclusions: Continued research will lead to a better understanding of the pharmacokinetic changes associated with structural modifications to the cathinone scaffold, and potentially in the long range, enhanced overdose and addiction therapy. Additionally, the areas of polydrug use and pharmacogenetics have been largely overlooked with regard to synthetic cathinones.

Captagon, known by its genetic name Fenethylline, is an addictive drug that complicates the War on Drugs. Captagon has a strong CNS stimulating effect than its primary metabolite, Amphetamine. However, multi-targets issues associated with the drug and metabolites as well as its underlying mechanisms have not been fully defined. In the present work, we applied our established drug-abuse chemogenomics-knowledgebase systems pharmacology approach to conduct targets/off-targets mapping (SP-Targets) investigation of Captagon and its metabolites for hallucination addiction, and also analyzed the cell signaling pathways for both Amphetamine and Theophylline with data mining of available literature. Of note, Amphetamine, an agonist for trace amine-associated receptor 1 (TAAR1) with enhancing dopamine signaling (increase of irritability, aggression, etc.), is the main cause of Captagon addiction; Theophylline, an antagonist that blocks adenosine receptors (e.g. A2aR) in the brain responsible for restlessness and painlessness, may attenuate the behavioral sensitization caused by Amphetamine. We uncovered that Theophylline's metabolism and elimination could be retarded due to competition and/or blockage of the CYP2D6 enzyme by Amphetamine; We also found that the synergies between these two metabolites cause Captagon's psychoactive effects to act faster and far more potently than those of Amphetamine alone. We carried out further molecular docking modeling and molecular dynamics simulation to explore the molecular interactions between Amphetamine and Theophylline and their important GPCRs targets, including TAAR1 and adenosine receptors. All of the systems pharmacology analyses and results will shed light insight into a better understanding of Captagon addiction and future drug abuse prevention.

Humankind has used and abused psychoactive drugs for millennia. Formally, a psychoactive drug is any agent that alters cognition and mood. The term "psychotropic drug" is neutral and describes the entire class of substrates, licit and illicit, of interest to governmental drug policy. While these drugs are prescribed for issues ranging from pain management to anxiety, they are also used recreationally. In fact, the current opioid epidemic is the deadliest drug crisis in American history. While the topic is highly politicized with racial, gender, and socioeconomic elements, there is no denying the toll drug mis- and overuse is taking on this country. Overdose, fueled by opioids, is the leading cause of death for Americans under 50 years of age, killing ca. 64,000 people in 2016. From a chemistry standpoint, the question is in what ways, if any, did organic chemists contribute to this problem? In this targeted review, we provide brief historical accounts of the main classes of psychoactive drugs and discuss several foundational total syntheses that ultimately provide the groundwork for producing these molecules in academic, industrial, and clandestine settings.

A previously developed liquid chromatographic simulator (see parts I and II) [1-3] is extended to allow for simulations of stationary phase gradients with isocratic and gradient mobile phases. Gradient stationary phases have recently been proposed as means of engineering unique chromatographic selectivities. In the present work, the simulator provides retention times and peak widths that agree with closed form theory for a linear gradient in retention factor and provides accurate retention time predictions for experimentally implemented continuous and discontinuous gradients. Calculation of discontinuous gradients implemented using the commercially available POPLC system have shown good agreement with experiment, with the largest deviation of the simulated retention time from experiment of 4.5%. In addition, simulations of a novel continuous amine gradient column show good agreement with experiment, and give insights into synergistic interactions on column. With the exception of solutes that show evidence of synergistic interactions, the simulated retention times are in agreement with the 95% confidence limits of the experimental values., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The broad diversity of synthetic cathinone psychostimulant drugs that are available to users complicates research efforts to provide understanding of health risks. Second generation cathinones pentedrone and pentylone are distinguished from each other by the 3,4-methylenedioxy structural motif (which distinguishes methamphetamine from 3,4-methylenedioxymethamphetamine) and each incorporates the α-alkyl chain motif contained in the transporter-inhibitor cathinones (3,4-methylenedioxypyrovalerone (MDPV), α-pyrrolidinopentiophenone (α-PVP)) but not in the monoamine releasers (mephedrone, methylone). Studies were conducted in male and female Wistar rats to compare locomotor and thermoregulatory effects of pentedrone, pentylone and methylone using an implanted radiotelemetry system. Reinforcing effects were assessed in female Wistar rats trained in the intravenous self-administration (IVSA) procedure and subjected to dose-substitution (0.025-0.3 m/gkg/inf) under a fixed-ratio 1 response contingency. Pentedrone, pentylone and methylone dose-effect curves were contrasted with those for α-PVP and α-pyrrolidinohexiophenone (α-PHP). Dose dependent increases in locomotion were observed after intraperitoneal injection of pentylone (0.5-10.0 mg/kg), pentedrone (0.5-10.0 mg/kg) or mephedrone (0.5-10.0 mg/kg) in male and female rats. The maximum locomotor effect was similar across drugs but lasted longest after pentedrone. Mean body temperature did not vary systematically more than 0.5 °C after pentedrone or pentylone in either sex. A sustained hyperthermia (0.4-0.8 °C) was observed for four hours after 10.0 mg/kg methylone in male rats. More infusions of pentedrone or pentylone were self-administered compared with methylone, but all three were less potent than α-PVP or α-PHP. These studies support the inference that second generation cathinones pentylone and pentedrone have abuse liability greater than that of methylone. This article is part of the Special Issue entitled 'Designer Drugs and Legal Highs.', (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Novel emerging drugs of abuse, also referred as new psychoactive substances, constitute an ever-changing mixture of chemical compounds designed to circumvent legislative controls by means of chemical modifications of previously banned recreational drugs. One such class, synthetic cathinones, namely β-keto derivatives of amphetamines, has been largely abused over the past decade. A number of new synthetic cathinones are detected each year, either in bulk powders/crystals or in biological matrices. It is therefore important to continuously monitor the supply of new synthetic derivatives and promptly report them. By using complementary analytical techniques (i.e. one- and two-dimensional NMR, FT-IR, GC-MS, HRMS and HPLC-UV), this study investigates the detection, identification and full characterization of 1-(4-methylphenyl)-2-(methylamino)pentanone (4-methylpentedrone, 4-MPD), 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl)hexanone (4F-PHP) and 1-(1,3-benzodioxol-5-yl)-2-(ethylamino)-1-pentanone (bk-EPDP), three emerging cathinone derivatives., (Copyright © 2017 John Wiley & Sons, Ltd.)

Color tests are a key tool for the rapid and simple identification of seized illicit drugs. This chapter outlines a series of color tests that can be used for the preliminary identification of new psychoactive substances such as cathinones, piperazines, tryptamines, and amphetamine-type stimulants.

Novel psychoactive substances have maintained a prominent role in the global drug culture, despite increased regulation by governing bodies. Novel compounds continue to become available on the market, often in "Ecstasy" or "Molly" formulations in lieu of MDMA, at a much faster rate than they can be properly characterized. The current study aimed to investigate the discriminative stimulus and locomotor effects of three putatively entactogenic compounds that have become increasingly prevalent on the drug market: 5-(2-aminopropyl)-benzofuran (5-APB), 6-(2-aminopropryl)-2,3-dihydrobenzofuran (6-APDB), and 4-fluoroamphetamine (4-FA). Locomotor stimulant effects were assessed in an open-field assay for locomotor activity using Swiss-Webster mice. Discriminative stimulus effects were assessed in Sprague-Dawley rats trained to discriminate either cocaine, methamphetamine, DOM, or MDMA from vehicle. The benzofuran compounds produced locomotor stimulation whereas 4-FA depressed locomotor activity. The benzofurans substituted for the discriminative stimulus effects of MDMA, but only partially or not at all for methamphetamine, cocaine, and DOM, whereas 4-FA fully substituted for MDMA, methamphetamine and cocaine, but not DOM. These results indicate an MDMA-like pattern of abuse might be expected for the benzofurans, whereas 4-FA may be substituted for psychostimulants and MDMA., (Copyright © 2017. Published by Elsevier B.V.)

Amphetamine (AMP), an indirectly acting psychostimulant approved for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children, adolescents, and adults, is among the most long-standing therapeutic agents in all of clinical psychopharmacology. This review focuses on AMP absorption, metabolism, and elimination brought to bear on comparative pharmacokinetics in its various formulations. A comprehensive search of the published literature was conducted using MEDLINE (PubMed) and Google Scholar databases through April 2017 to retrieve all pertinent in vitro and human studies for review and synthesis. Additionally, Food and Drug Administration (FDA) databases were accessed for otherwise unavailable data when possible. Initially available as racemic (dl)-AMP, this drug was later supplanted by enantiopure (d)-AMPH or enantioenriched (75:25 dl)-AMP formulations; although racemic AMP returned as an approved drug to treat ADHD in 2014. Presently, there are several immediate-release (IR) formulations available, including d-AMP, dl-AMP, and mixed amphetamine salts, which are neither racemic nor the pure d-enantiomer (i.e., a 3:1 mixture of d-AMP and l-AMP). Furthermore, new modified-release AMP formulations, including an oral suspension and an orally disintegrating tablet, are now available. A lysine-bonded prodrug form of d-AMP also serves as a treatment option. Oral AMP is rapidly absorbed, with high absolute bioavailability, followed by extensive metabolism involving multiple enzymes. Some metabolic pathways exhibit stereoselective biotransformations favoring the l-isomer substrate. Drug exposure exhibits dose-proportional pharmacokinetics. Body weight is a fundamental determinant of differences in observed AMP plasma concentrations. IR formulations typically provide a T max from 2 to 3 hours. In replicated studies, children exhibit a shorter plasma T 1/2 (∼7 hours) relative to adults (∼10 to 12 hours). There are few documented pharmacokinetic drug interactions of clinical significance beyond influences of drug-induced alteration of urinary pH. The array of AMP formulations addressed in this review offer flexibility in dosing, drug onset, and offset to assist in individualized pharmacotherapy of ADHD.

N-hydroxyamphetamine (AmphNHOH) is an oxidative metabolite of amphetamine and methamphetamine. It is known to form inhibitory complexes upon binding to heme proteins. However, its interactions with myoglobin (Mb) and hemoglobin (Hb) have not been reported. We demonstrate that the reactions of AmphNHOH with ferric Mb and Hb generate the respective heme-nitrosoamphetamine derivatives characterized by UV-vis spectroscopy. We have determined the X-ray crystal structure of the H64A Mb-nitrosoamphetamine complex to 1.73 Å resolution. The structure reveals the N-binding of the nitroso-d-amphetamine isomer, with no significant H-bonding interactions between the ligand and the distal pocket amino acid residues., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The dopamine and serotonin transporter proteins (DAT, SERT) play a vital role in behavior and mental illness. Although their substrate transport has been studied extensively, the molecular basis of their selectivity is not completely understood yet. In this study, we exploit molecular dynamics simulations combined with mutagenesis studies to shed light on the driving factors for DAT-over-SERT selectivity of a set of cathinones. Results indicate that these compounds can adopt two binding modes of which one is more favorable. In addition, free energy calculations indicated the substrate binding site (S1) as the primary recognition site for these ligands. By simulating DAT with SERT-like mutations, we hypothesize unsubstituted cathinones to bind more favorably to DAT, due to a Val152 offering more space, as compared to the bulkier Ile172 in SERT. This was supported by uptake inhibition measurements, which showed an increase in activity in SERT-I172V., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background and Aims: On-line drug markets flourish and consumers have high expectations of on-line quality and drug value. The aim of this study was to (i) describe on-line drug purchases and (ii) compare on-line with off-line purchased drugs regarding purity, adulteration and price., Design: Comparison of laboratory analyses of 32 663 drug consumer samples (stimulants and hallucinogens) purchased between January 2013 and January 2016, 928 of which were bought on-line., Setting: The Netherlands., Measurements: Primary outcome measures were (i) the percentage of samples purchased on-line and (ii) the chemical purity of powders (or dosage per tablet); adulteration; and the price per gram, blotter or tablet of drugs bought on-line compared with drugs bought off-line., Findings: The proportion of drug samples purchased on-line increased from 1.4% in 2013 to 4.1% in 2015. The frequency varied widely, from a maximum of 6% for controlled, traditional substances [ecstasy tablets, 3,4-methylenedioxy-methamphetamine (MDMA) powder, amphetamine powder, cocaine powder, 4-bromo-2,5-dimethoxyphenethylamine (2C-B) and lysergic acid diethylamide (LSD)] to more than a third for new psychoactive substances (NPS) [4-fluoroamphetamine (4-FA), 5/6-(2-aminopropyl)benzofuran (5/6-APB) and methoxetamine (MXE)]. There were no large differences in drug purity, yet small but statistically significant differences were found for 4-FA (on-line 59% versus off-line 52% purity for 4-FA on average, P = 0.001), MDMA powders (45 versus 61% purity for MDMA, P = 0.02), 2C-B tablets (21 versus 10 mg 2C-B/tablet dosage, P = 0.49) and ecstasy tablets (131 versus 121 mg MDMA/tablet dosage, P = 0.05). The proportion of adulterated samples purchased on-line and off-line did not differ, except for 4-FA powder, being less adulterated on-line (χ 2  = 8.3; P < 0.02). Drug prices were mainly higher on-line, ranging for various drugs from 10 to 23% higher than that of drugs purchased off-line (six of 10 substances: P < 0.05)., Conclusions: Dutch drug users increasingly purchase drugs on-line: new psychoactive substances in particular. Purity and adulteration do not vary considerably between drugs purchased on-line and off-line for most substances, while on-line prices are mostly higher than off-line prices., (© 2016 Society for the Study of Addiction.)

The serotonin transporter (SERT) and other monoamine transporters operate in either a forward transport mode where the transporter undergoes a full transport cycle or an exchange mode where the transporter seesaws through half-cycles. Amphetamines trigger the exchange mode, leading to substrate efflux. This efflux was proposed to rely on the N terminus, which was suggested to adopt different conformations in the inward facing, outward facing and amphetamine-bound states. This prediction was verified by tryptic digestion of SERT-expressing membranes: in the absence of Na + , the N terminus was rapidly digested. Amphetamine conferred protection against cleavage, suggesting a relay between the conformational states of the hydrophobic core and the N terminus. We searched for a candidate segment that supported the conformational switch by serial truncation removing 22 (ΔN22), 32 (ΔN32), or 42 (ΔN42) N-terminal residues. This did not affect surface expression, inhibitor binding, and substrate influx. However, amphetamine-induced efflux by SERT-ΔN32 or SERT-ΔN42 (but not by SERT-ΔN22) was markedly diminished. We examined the individual steps in the transport cycle by recording transporter-associated currents: the recovery rate of capacitive peak, but not of steady state, currents was significantly lower for SERT-ΔN32 than that of wild type SERT and SERT-ΔN22. Thus, the exchange mode of SERT-ΔN32 was selectively impaired. Our observations show that the N terminus affords the switch between transport modes. The findings are consistent with a model where the N terminus acts as a lever to support amphetamine-induced efflux by SERT., (© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.)

A method for the statistical comparison of mass spectral data is demonstrated for applications in controlled substance analysis. The method uses an unequal variance t-test at each mass-to-charge ratio in the scan range to determine if two spectra are statistically associated or discriminated. If the two spectra are associated, a random-match probability is calculated to estimate the likelihood that the mass spectral fragmentation pattern in question occurs by random chance alone. If the two spectra are discriminated, the fragment ions responsible for the discrimination are determined. In this work, mass spectral data from case samples containing amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), phentermine, and psilocin were investigated. All spectra were collected in an accredited forensic laboratory using routine methods for controlled substance analysis. Using the statistical method, spectra of case samples were statistically associated to the corresponding reference standard at the 99.9% confidence level. In these instances, random-match probabilities ranged from 10 -39 to 10 -29 , indicating the probability that the characteristic fragmentation pattern occurred by random chance is extremely small. Further, spectra of case samples were discriminated from other reference standards at the 99.9% or 99.0% confidence level, with 1-26 ions responsible for discrimination in each comparison., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Until recently, there was rather little interest in the structure-activity relationships (SARs) of cathinone analogs because so few agents were available and because they represented a relatively minor drug abuse problem. Most of the early SAR was formulated on the basis of behavioral (e.g., locomotor and drug discrimination) studies using rodents. With the emergence on the clandestine market in the last few years of a large number of new cathinone analogs, termed "synthetic cathinones", and the realization that they likely act at dopamine, norepinephrine, and/or serotonin transporters as releasing agents (i.e., as substrates) or reuptake inhibitors (i.e., as transport blockers), it has now become possible to better examine their SAR and even their quantitative SAR (QSAR), in a more effective and systematic manner. An SAR picture is beginning to emerge, and key structural features, such as the nature of the terminal amine, the size of the α-substituent, stereochemistry, and the presence and position of aromatic substituents, are being found to impact action (i.e., as releasing agents or reuptake inhibitors) and transporter selectivity.

Amphetamine and its derivatives gained high popularity on the illegal drug market. In the last few years, a lot of new psychoactive compounds structurally related to amphetamine, such as 4-fluoroamphetamine and 4-fluoromethamphetamine swamped the drug market. They were designed to circumvent prohibition of amphetamine and N-methylamphetamine and are distributed via the Internet. Often, a halogen atom is introduced into the phenyl ring of amphetamine to turn the illegal amphetamine legal. Since amphetamines possess a chiral centre, two enantiomers are available, which might differ in activity. Since most of them are partially not commercially available to date, synthesis and characterisation of amphetamine derivatives might help authorities to identify these substances of abuse. The aim of this study was to investigate self-synthesized amphetamines concerning their identity and their enantiomeric status either by GC-MS or by HPLC. For GC-MS, derivatization with (R)-(+)-α-methoxy-α-trifluoromethylphenylacetic acid (MTPA) or (1R)-(-)-menthylchloroformate prior to analysis on a HP-5MS column was done. For chiral separation by HPLC a LiChrospher 100 RP-18e column and sulfated beta-cyclodextrin added to the mobile phase as chiral selector were used. Enantioseparation was accomplished successfully by both methods. Furthermore, simultaneous chiral separation of three positions isomers, namely 2-fluoroamphetamine, 3-fluoroamphetamine and 4-fluoroamphetamine, was shown successfully by HPLC., (Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.)

Objectives: To identify banned and discouraged-use ingredients, such as ephedra, 1,3-dimethylamylamine, and beta-methyl-phenylethylamine, in readily available weight loss dietary supplements within a 10-mile radius of Regis University., Methods: A list of banned and discouraged-use ingredients was compiled with the use of the Food and Drug Administration (FDA) dietary supplement website which provides information on supplement ingredients that are no longer legal or are advised against owing to adverse event reporting. Investigators visited all retail outlet stores within a 10-mile radius of Regis University in Denver, Colorado. Retail chains were not duplicated and only one of each chain was evaluated., Results: A total of 51 weight loss supplement products from retail stores were found with banned or discouraged-use substances listed on their labels. At least one banned ingredient was found to be listed on the product labels in 17 of the 51 studied supplements (33%). At least one discouraged-use ingredient was found in 46 of the 51 products (90%). Retail outlet stores dedicated to supplements and sports nutrition alone were found to have the greatest number of weight loss supplements that included banned and discouraged-use ingredients., Conclusion: The FDA has taken action to remove some weight loss supplements from the market that contain banned ingredients. Unfortunately, based on the findings of this study, it is evident that products containing these ingredients remain on the market today., (Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

In a seizure of German custom authorities four N-(ortho-methoxybenzyl)amines with amphetamine partial structure were obtained as pure compounds: N-(ortho-methoxybenzyl)-3,4-dimethoxyamphetamine (3,4-DMA-NBOMe (1)), N-(ortho-methoxybenzyl)-4-ethylamphetamine (4-EA-NBOMe (2)), N-(ortho-methoxybenzyl)-4-methylmethamphetamine (4-MMA-NBOMe (3)), and N-(ortho-methoxybenzyl)-5-(2-aminopropyl)benzofuran (5-APB-NBOMe (4)). The compounds have been detected in Germany for the first time and no analytical data had been previously published. Mass spectrometric (MS), infrared (IR) spectroscopic, and nuclear magnetic resonance (NMR) spectroscopic data are presented. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

Fenethylline is a theophylline derivative of amphetamine having stimulant effects similar to those of other amphetamine-type derivatives. Fenethylline was used as medicament for hyperactivity disorders in children, narcolepsy and depression, but it has also been used as a drug of abuse under the common name of 'captagon'. Unlike other drugs of abuse, the clandestine synthesis of fenethylline is simple, using inexpensive laboratory instrumentation and raw materials legal to obtain. A review of all the existing knowledge of fenethylline is reported, concerning its chemistry, synthesis, pharmacology and toxicology, legislation, its prevalence and use as drug of abuse, as well as its analysis in biological or seized samples. Published or reported captagon-related cases and seizures are also presented. All the reviewed information was gathered through a detailed search of PubMed and the Internet. The primary drug market for fenethylline (as captagon) has traditionally been countries located on the Arabian Peninsula but also North Africa since 2013. In Arab countries, millions of captagon tablets are seized every year which represents one-third of global amphetamines seizures within a year. Furthermore, three of four patients treated for drug problems in Saudi Arabia are addicted to amphetamines, almost exclusively in the form of captagon. Significant information on fenethylline is provided for pharmacologists, toxicologists and forensic pathologists. Fenethylline, although old, has recently been introduced to the drug market, especially in Arab countries. Continuous community alertness is needed to tackle this current growing phenomenon., (© 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).)

β-Methylphenylethylamines are positional isomers of amphetamines and have been discovered in sporting supplements. Although the fragmentation of the β-methylphenylethylamine and N-methyl-β-methylphenylethylamine in gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) systems is significantly different to their amphetamine and methylamphetamine isomers, under electrospray ionization commonly used in liquid chromatography-mass spectrometry (LC-MS) systems, the fragmentation of each of the isomeric pairs is almost identical. The similarities in fragmentation make it possible for the misidentification of the β-methylphenylethylamines as the illicit amphetamines. It is proposed that the similarities are due to a fragmentation pathway involving a common phenonium ion intermediate. By careful control of fragmentation energies in liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems and/or close examination of the relative abundances of product ions formed by collision-induced dissociation (qualifier ratios), it is possible to distinguish the β-methylphenylethylamines from the amphetamines, even if significant retention time separation is not achieved. In liquid chromatography-electrospray ionization-quadrupole time of flight (LC-ESI-QTOF) systems the mass spectra of the β-methylphenylethylamines are identical to their amphetamine isomers. In such systems, retention time separation of the isomers is critical to avoid misidentification. During this study β-methylphenylethylamine and N-methyl-β-methylphenylethylamine have been identified in commercially available sporting supplements and oral fluid samples taken during the course of road-side drugs-in-drivers and workplace testing programmes. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

In recent years, new amphetamine derivatives with modified ring systems were sold and consumed as new drugs of abuse. They belong together with other new drugs of abuse classes to the so-called new psychoactive substances (NPS). The chemistry, pharmacology, toxicology, metabolism, and toxicokinetics are shortly discussed of camfetamine, 3 methylphenyl-amphetamines (2-MA, 3-MA, and 4-MA), 2-methiopropamine (2-MPA), and 5-(2-aminopropyl)benzofuran (5-APB), 6-(2-aminopropyl)benzofuran (6-APB, so-called "benzofury") and their N-methyl derivatives 5-MAPB and 6-MAPB. Only a rough assessment of the pharmacology and toxicology NPS can be performed in most cases using published data of analogs, trip reports, and described clinical cases. Accordingly, they all act more or less as central nervous stimulants mainly by increasing the concentration of the neurotransmitters noradrenaline, dopamine, and serotonin (5-HT) by inducing their release and reuptake inhibition. Thus, the acute toxicity is associated with the sympathomimetic effects, such as mydriasis, hyperthermia, hypertension, tachycardia, insomnia, and anxiety. With the exception of 5- and 6-APB, these NPS were extensively metabolized by N-demethylation and/or aromatic hydroxylation catalyzed by various cytochrome P450 isoenzymes followed by partial glucuronidation and/or sulfation. For urinalysis, the unchanged drugs and/or the nor-metabolites are the main targets.

The synthetic cathinones represent an important class of designer drugs. The widespread attention and publicity associated with these psychostimulants have resulted in numerous legislative actions at state and federal levels throughout the USA. These amphetamine-like compounds are characterized by a β-keto functional group. Although the synthetic cathinones share many properties of their phenethylamine counterparts, the presence of the ketone moiety is responsible for a number of unique and distinct differences in terms of their chemical characteristics and properties. Thermal degradation of methcathinone was first reported several decades ago but has received limited attention. In this study, we identified in situ thermal degradation products for 18 cathinones during gas chromatography-mass spectrometry (GC-MS) analysis. Oxidative degradation arises from the loss of two hydrogens, yielding a characteristic 2 Da mass shift. Degradation products were characterized by prominent iminium base peaks with mass-to-charge ratios 2 Da lower than the parent drug, and in the case of the pyrrolidine-containing cathinones, prominent molecular ions arising from the 2,3-enamine. Chromatographic and mass spectroscopic data are described for 4-ethylmethcathinone, 4-methylethcathinone, buphedrone, butylone, ethcathinone, ethylone, flephedrone, 3,4-methylenedioxy-α-pyrrolidinobutiophenone, 3,4-methylenedioxypyrovalerone, mephedrone, methcathinone, methedrone, methylone, 4-methyl-α-pyrrolidinobutiophenone, naphyrone, pentedrone, pentylone and pyrovalerone. Degradation was minimized by lowering injection temperatures, residence time in the inlet and eliminating active sites during chromatographic analysis. Chromatographic and mass spectral data for the cathinone degradation products are presented and discussed within the context of forensic toxicological analysis, selection of appropriate instrumental methods and implications for the interpretation of results., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

A simple and inexpensive method for the identification of four substituted amphetamines, namely, 3,4-methylenedioxy methamphetamine (MDMA), methamphetamine (MA), 3,4-methylenedioxy amphetamine (MDA) and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) was developed using an in-house constructed semi-automated portable capillary electrophoresis instrument (CE) with capacitively coupled contactless conductivity detection (C(4)D). Arginine 10mM adjusted to pH4.5 with acetic acid was found to be the optimal background electrolyte for the CE-C(4)D determination of these compounds. The best detection limits achieved with and without a sample preconcentration process were 10ppb and 500ppb, respectively. Substituted amphetamines were found in different seized illicit club drug tablets and urine samples collected from different suspected users. Good agreement between results from CE-C(4)D and those with the confirmation method (GC-MS) was achieved, with correlation coefficients for the two pairs of data of more than 0.99., (Copyright © 2015 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.)

The global increase in the production and abuse of cathinone-derived New Psychoactive Substances (NPSs) has developed the requirement for rapid, selective and sensitive protocols for their separation and detection. Electrochemical sensing of these compounds has been demonstrated to be an effective method for the in-field detection of these substances, either in their pure form or in the presence of common adulterants, however, the technique is limited in its ability to discriminate between structurally related cathinone-derivatives (for example: (±)-4′-methylmethcathinone (4-MMC, 2a) and (±)-4′-methyl-N-ethylmethcathinone (4-MEC, 2b) when they are both present in a mixture. In this paper we demonstrate, for the first time, the combination of HPLC-UV with amperometric detection (HPLC-AD) for the qualitative and quantitative analysis of 4-MMC and 4-MEC using either a commercially available impinging jet (LC-FC-A) or custom-made iCell channel (LC-FC-B) flow-cell system incorporating embedded graphite screen-printed macroelectrodes. The protocol offers a cost-effective, reproducible and reliable sensor platform for the simultaneous HPLC-UV and amperometric detection of the target analytes. The two systems have similar limits of detection, in terms of amperometric detection [LC-FC-A: 14.66 μg mL(-1) (2a) and 9.35 μg mL(-1) (2b); LC-FC-B: 57.92 μg mL(-1) (2a) and 26.91 μg mL(-1) (2b)], to the previously reported oxidative electrochemical protocol [39.8 μg mL(-1) (2a) and 84.2 μg mL(-1) (2b)], for two synthetic cathinones, prevalent on the recreational drugs market. Though not as sensitive as standard HPLC-UV detection, both flow cells show a good agreement, between the quantitative electroanalytical data, thereby making them suitable for the detection and quantification of 4-MMC and 4-MEC, either in their pure form or within complex mixtures. Additionally, the simultaneous HPLC-UV and amperometric detection protocol detailed herein shows a marked improvement and advantage over previously reported electroanalytical methods, which were either unable to selectively discriminate between structurally related synthetic cathinones (e.g. 4-MMC and 4-MEC) or utilised harmful and restrictive materials in their design.

A novel approach for the preparation of steroids containing a chiral center at C-25 is reported. The key stereochemistry inducing step was asymmetric alkylation of pseudoephenamine amides of steroidal C-26 acids. The reaction proceeded with high diastereoselectivity (dr > 99 : 1). The developed methodology was successfully applied to the synthesis of (25R)- and (25S)-cholestenoic acids as well as (25R)- and (25S)-26-hydroxy brassinolides.

In monoaminergic neurons, the vesicular transporters and the plasma membrane transporters operate in a relay. Amphetamine and its congeners target this relay to elicit their actions: most amphetamines are substrates, which pervert the relay to elicit efflux of monoamines into the synaptic cleft. However, some amphetamines act as transporter inhibitors. Both compound classes elicit profound psychostimulant effects, which render them liable to recreational abuse. Currently, a surge of new psychoactive substances occurs on a global scale. Chemists bypass drug bans by ingenuous structural variations, resulting in a rich pharmacology. A credible transport model must account for their distinct mode of action and link this to subtle differences in activity and undesired, potentially deleterious effects., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Synapse degeneration is an early and invariant feature of neurodegenerative diseases. Indeed, synapse loss occurs prior to neuronal degeneration and correlates with the symptom severity of these diseases. However, the molecular mechanisms that trigger synaptic loss remain poorly understood. Here we demonstrate that deficient Wnt signalling elicits synaptic degeneration in the adult striatum. Inducible expression of the secreted Wnt antagonist Dickkopf1 (Dkk1) in adult mice (iDkk1) decreases the number of cortico-striatal glutamatergic synapses and of D1 and D2 dopamine receptor clusters. Synapse loss occurs in the absence of axon retraction or cell death. The remaining excitatory terminals contain fewer synaptic vesicles and have a reduced probability of evoked transmitter release. IDkk1 mice show impaired motor coordination and are irresponsive to amphetamine. These studies identify Wnts as key endogenous regulators of synaptic maintenance and suggest that dysfunction in Wnt signalling contributes to synaptic degeneration at early stages in neurodegenerative diseases.