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1.
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.  相似文献   

2.
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.  相似文献   

3.

Purpose

The analysis of products which contain synthetic cannabinoids (SCs) is very challenging due to their diversity and rapidly changing SC structures, variable herbal matrices and, above all, inaccessibility of reference standards. Therefore, the aim of this study was to develop a method which allows quantification of SCs’ contents in herbal blends without their reference standards.

Methods

Identification of SCs was performed using liquid chromatographyhigh-resolution tandem mass spectrometry with a quadrupole time-of-flight analyser (LCQTOF-MS/MS). A liquid chromatography–charged aerosol detection (LCCAD) method with unified calibration for the quantification of SCs was developed and validated. Two available reference standards were used as universal standards. Quantitative analysis using a nuclear magnetic resonance spectroscopy method was also performed to externally validate the developed LCCAD method.

Results

All peaks of SCs observed in LCCAD chromatograms were identified by LCQTOF-MS/MS. Validation data and results from a CAD response evaluation indicated that the elaborated quantitative method was sufficiently accurate for the determination of SCs belonging to various chemical families. The LCCAD method turned out to be very flexible, because it was successfully applied for the analysis of 19 herbal products.

Conclusions

In this study, methods which enable identification and quantification of currently known SCs as well as novel unknown derivatives without their reference standards were developed. These methods can be applied to the control of suspect SC products and may support the risk assessment of SC presence on the market. To our knowledge, this is the first trial to use LC–CAD for unified quantification of SCs without their reference standards.
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The synthesis of 3-(2′-[18F]fluoroethyl)spiperone (1c), a radiotracer useful for imaging the brain dopamine receptor system in vivo using positron emission tomography, is described. Precursors of 1c, the functional 3-N-alkyl derivatives of spiperone (4), were prepared by the alkylation of the amide group in spiperone (2a) by 1,2-disubstituted ethanes under phase transfer conditions. A comprehensive evaluation of the reaction of the derivatives 4a–h with no-carrier-added K 18F/Kryptofix clearly indicated that the ketalized derivatives 4e–h were the choice of the precursors for 1c. The i.r., MS and NMR spectral data suggested that under phase transfer reaction conditions, the amide nitrogen was preferentially alkylated. To provide a firm basis for comparison with related analogues, an x-ray analysis was performed on a single crystal of 3-(2′-fluoroethyl)spiperone (1d). The tomographic behavior of 1c in human brain tissue was measured for more than 7 h and was consistent with the labeling of dopamine D-2 receptors.  相似文献   

6.

Purpose

The thymidine analog 3′-deoxy-3′-[18F]fluorothymidine (18F-FLT) has been developed as a positron emission tomography (PET) tracer to assess the proliferation activity of tumors in vivo. The present study investigated the relationship between the kinetic parameters of 18F-FLT in vivo and thymidine kinase-1 (TK-1) expression and cell proliferation rate in vitro, and blood–brain barrier (BBB) breakdown in human brain gliomas.

Methods

A total of 21 patients with newly diagnosed gliomas were examined by 18F-FLT PET kinetic analysis. Maximum standardized uptake value (SUVmax) and tumor-to-normal (T/N) ratio of 18F-FLT in the tumor and 18F-FLT kinetic parameters in the corresponding contralateral region were determined. The expression levels of TK-1 protein and mRNA were determined by immunohistochemistry (IHC) and real-time polymerase chain reaction (PCR), respectively, using surgical specimens. The cell proliferation rate of the tumor was determined in terms of the Ki-67 labeling index. BBB breakdown was evaluated on MR images with contrast enhancement.

Results

18F-FLT SUVmax and T/N ratio were significantly correlated with the influx rate constant (K 1; P?=?0.001 and P?<?0.001, respectively), but not with the phosphorylation rate constant (k 3). IHC and real-time PCR studies demonstrated a significant correlation between K 1 and TK-1 mRNA expression (P?=?0.001), but not between k 3 and TK-1 protein and mRNA expression. Linear regression analysis revealed a significant correlation between K 1 and the Ki-67 index (P?=?0.003), but not between k 3 and the Ki-67 index. TK-1 mRNA expression was significantly correlated with the Ki-67 index (P?=?0.009). 18F-FLT SUVmax and T/N ratio were significantly correlated with BBB breakdown evaluated by contrast enhancement in MR images (P?=?0.003 and P?=?0.011, respectively).

Conclusion

These results indicate that 18F-FLT uptake in the tumor is significantly related to transport through the disrupted BBB, but not through phosphorylation activity. Although the tissue TK-1 expression reflects tumor proliferation activity, the phosphorylation rate constant k 3 determined by 18F-FLT PET kinetic analysis does not accurately reflect TK-1 expression in the tissue and should not be used as a surrogate biomarker of cell proliferation activity in human brain gliomas.  相似文献   

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