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21.
The rapid diffusion of new psychoactive substances (NPS) presents unprecedented challenges to both customs authorities and analytical laboratories involved in their detection and characterization. In this study an analytical approach to the identification and structural elucidation of a novel synthetic cannabimimetic, quinolin-8-yl-3-[(4,4-difluoropiperidin-1-yl) sulfonyl]-4-methylbenzoate (2F-QMPSB), detected in seized herbal material, is detailed. An acid precursor 4-methyl-3-(4,4-difluoro-1-piperidinylsulfonyl) benzoic acid (2F-MPSBA), has also been identified in the same seized material. After extraction from the herbal material the synthetic cannabimimetic, also referred to as synthetic cannabinoid receptor agonists or “synthetic cannabinoids”, was characterized using gas chromatography-mass spectrometry (GC-MS), 1H, 13C, 19F and 15N nuclear magnetic resonance (NMR) and high-resolution tandem mass spectrometry (HR-MS/MS) combined with chromatographic separation. A cheminformatics platform was used to manage and interpret the analytical data from these techniques.  相似文献   
22.
Cannabis sativa is one of the oldest medicinal plants in the world. It was introduced into western medicine during the early 19th century. It contains a complex mixture of secondary metabolites, including cannabinoids and non-cannabinoid-type constituents. More than 500 compounds have been reported from C. sativa, of which 125 cannabinoids have been isolated and/or identified as cannabinoids. Cannabinoids are C21 terpeno-phenolic compounds specific to Cannabis. The non-cannabinoid constituents include: non-cannabinoid phenols, flavonoids, terpenes, alkaloids and others. This review discusses the chemistry of the cannabinoids and major non-cannabinoid constituents (terpenes, non-cannabinoid phenolics, and alkaloids) with special emphasis on their chemical structures, methods of isolation, and identification.  相似文献   
23.
Short and highly efficient stereoselective syntheses provide machaeriols and cannabinoids in a divergent approach starting from a common precursor, commercially available (S)‐perillic acid. Key features of the novel strategy are a stereospecific palladium‐catalyzed decarboxylative arylation and a one‐pot sequence comprising a stereoselective hydroboration followed by oxidation or reduction of the corresponding intermediary boranes. The divergent approach is convincingly demonstrated by the five‐step syntheses of (+)‐machaeriol B, (+)‐machaeriol D, and related analogues, and the four‐step synthesis of (+)‐Δ8‐THC and an analogue.  相似文献   
24.
The analysis of synthetic cannabinoids in human matrices is of particular importance in the fields of forensic and clinical toxicology since cannabis users partly shift to the consumption of ‘herbal mixtures’ as a legal alternative to cannabis products in order to circumvent drug testing. However, comprehensive methods covering the majority of synthetic cannabinoids already identified on the drug market are still lacking. In this article, we present a fully validated method for the analysis of 30 synthetic cannabinoids in human serum utilizing liquid‐liquid extraction and liquid chromatography‐electrospray ionization tandem mass spectrometry. The method proved to be suitable for the quantification of 27 substances. The limits of detection ranged from 0.01 to 2.0 ng/mL, whereas the lower limits of quantification were in the range from 0.1 to 2.0 ng/mL. The presented method was successfully applied to 833 authentic serum samples during routine analysis between August 2011 and January 2012. A total of 227 (27%) samples was tested positive for at least one of the following synthetic cannabinoids: JWH‐018, JWH‐019, JWH‐073, JWH‐081, JWH‐122, JWH‐200, JWH‐203, JWH‐210, JWH‐307, AM‐2201 and RCS‐4. The most prevalent compounds in positive samples were JWH‐210 (80%), JWH‐122 (63%) as well as AM‐2201 (29%). Median serum concentrations were all below 1.0 ng/mL. These findings demonstrate a significant shift of the market of synthetic cannabinoids towards substances featuring a higher CB1 binding affinity and clearly emphasize that the analysis of synthetic cannabinoids in serum or blood samples requires highly sensitive analytical methods covering a wide spectrum of substances. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
25.
Dried urine spots (DUS) represent a potential alternative sample storage for forensic toxicological analysis. The aim of the current study was to develop and validate a liquid chromatographic tandem mass spectrometric procedure for the detection and quantitative determination of cannabinoids and metabolites in DUS. A two-step extraction was performed on DUS and urine samples. An LC-MS/MS system was operated in multiple reaction monitoring and positive polarization mode. The method was checked for sensitivity, specificity, linearity, accuracy, precision, recovery, matrix effects and carryover. The method was applied to 70 urine samples collected from healthy volunteers and drug addicts undergoing withdrawal treatment. The method was successfully developed for DUS. LODs lower than 2.0 ng/mL were obtained for all the monitored substances. All the validation parameters fulfilled the acceptance criteria either for DUS or urine. Among the real samples, 45 cases provided positive results for at least one compound. A good quali-quantitative agreement was obtained between DUS and urine. A good stability of THC, THCCOOH and THCCOOH-gluc was observed after a 24 h storage, in contrast to previously published results. DUS seems to provide a good alternative storage condition for urine that should be checked for the presence of cannabinoids and metabolites.  相似文献   
26.
Cannabis is well-known for its numerous therapeutic activities, as demonstrated in pre-clinical and clinical studies primarily due to its bioactive compounds. The Cannabis industry is rapidly growing; therefore, product development and extraction methods have become crucial aspects of Cannabis research. The evaluation of the current extraction methods implemented in the Cannabis industry and scientific literature to produce consistent, reliable, and potent medicinal Cannabis extracts is prudent. Furthermore, these processes must be subjected to higher levels of scientific stringency, as Cannabis has been increasingly used for various ailments, and the Cannabis industry is receiving acceptance in different countries. We comprehensively analysed the current literature and drew a critical summary of the extraction methods implemented thus far to recover bioactive compounds from medicinal Cannabis. Moreover, this review outlines the major bioactive compounds in Cannabis, discusses critical factors affecting extraction yields, and proposes future considerations for the effective extraction of bioactive compounds from Cannabis. Overall, research on medicinal marijuana is limited, with most reports on the industrial hemp variety of Cannabis or pure isolates. We also propose the development of sustainable Cannabis extraction methods through the implementation of mathematical prediction models in future studies.  相似文献   
27.
The innate immune response to bacterial and viral molecules involves the coordinated production of cytokines, chemokines, and type I interferons (IFNs), which is orchestrated by toll-like receptors (TLRs). TLRs, and their intracellular signalling intermediates, are closely associated with multiple sclerosis (MS) pathogenesis. Recent data from our laboratory reported that the plant-derived cannabinoids, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), regulate viral and bacterial inflammatory signalling pathways controlled by TLR3 and TLR4 in macrophages. The aim of this study was to assess the impact of THC and CBD, when delivered in isolation and in combination (1:1), on TLR3- and TLR4-dependent signalling in peripheral blood mononuclear cells (PBMCs) from people with MS (pwMS; n = 21) and healthy controls (HCs; n = 26). We employed the use of poly(I:C) and lipopolysaccharide (LPS) to induce viral TLR3 and bacterial TLR4 signalling, and PBMCs were pre-exposed to plant-derived highly purified THC (10 μM), CBD (10 μM), or a combination of both phytocannabinoids (1:1 ratio, 10:10 μM), prior to LPS/poly(I:C) exposure. TLR3 stimulation promoted the protein expression of the chemokine CXCL10 and the type I IFN-β in PBMCs from both cohorts. THC and CBD (delivered in 1:1 combination at 10 μM) attenuated TLR3-induced CXCL10 and IFN-β protein expression in PBMCs from pwMS and HCs, and this effect was not seen consistently when THC and CBD were delivered alone. In terms of LPS, TLR4 activation promoted TNF-α expression in PBMCs from both cohorts, and, interestingly, CBD when delivered alone at 10 μM, and in combination with THC (in 1:1 combination at 10 μM), exacerbated TLR4-induced TNF-α protein expression in PBMCs from pwMS and HCs. THC and CBD displayed no evidence of toxicity in primary PBMCs. No significant alteration in the relative expression of TLR3 and TLR4 mRNA, or components of the endocannabinoid system, including the cannabinoid receptor CB1 (encoded by CNR1 gene) and CB2 (encoded by CNR2 gene), and endocannabinoid metabolising enzymes, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MGLL), was determined in PBMCs from pwMS versus HCs. Given their role in inflammation, TLRs are clinical targets, and data herein identify CBD and THC as TLR3 and TLR4 modulating drugs in primary immune cells in vitro. This offers insight on the cellular target(s) of phytocannabinoids in targeting inflammation in the context of MS.  相似文献   
28.
为测定新型"香料"毒品中常见的合成大麻素成分,研究开发了高效液相色谱-三重四极杆质谱联用分析方法。采用安捷伦Poroshell 120 EC-C18(3.0 mm×50 mm,2.7μm)色谱柱,以高纯水-甲醇作流动相进行梯度洗脱,柱温30℃,流速0.3 m L/min。采用电喷雾电离-正离子(ESI+)、负离子(ESI-)分段检测模式,并对合成大麻素的质谱特征和离子碎裂规律进行研究。结果表明,采用该方法可以实现对常见10种合成大麻素的定性和定量分析,正、负离子模式下检测的目标物分别在1~100,10~1 000 ng/m L范围内呈良好线性,日内相对标准偏差(RSD)均不大于3.2%,日间RSD均不大于6.3%。经加标回收率测定和实际样本检验,该方法快速、准确、灵敏、可靠,适用于新型"香料"毒品中常见合成大麻素成分的定性定量检测。  相似文献   
29.
The first total synthesis of cannabimovone from Cannabis sativa and anhydrocannabimovone was achieved by means of a highly stereoselective gold(I)‐catalyzed cycloisomerization. The results led to reassignment of the structure of anhydrocannabimovone.  相似文献   
30.
Herbal mixtures, such as ‘Spice’, containing cannabimimetic compounds are easily available on the Internet and have become increasingly popular among people having to undergo urine drug testing, as these compounds are not detected by current immunochemical tests. For analysis of urine samples, knowledge of the main metabolites is necessary as the unchanged compounds are usually not found in urine after consumption. In this paper, the identification of the major metabolites of the currently most common seven synthetic cannabinoids is presented. Urine samples from patients of psychiatric facilities known to have consumed synthetic cannabinoids were screened by LC‐MS/MS and HR‐MS/MS techniques, and the major metabolites for each of the following synthetic cannabinoids were identified by their enhanced product ion spectra and accurate mass measurement: JWH‐018, JWH‐073, JWH‐081, JWH‐122, JWH‐210, JWH‐250 and RCS‐4. The major metabolic pathway is monohydroxylation either at the N‐alkyl side chain, the naphthyl moiety or the indole moiety. In addition, metabolites with carboxylated alkyl chains were identified for some of the compounds. These results facilitate the design of urine screening methods for detecting consumption of synthetic cannabinoids. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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