在互联网上销售的合成大麻素的NMR光谱参考数据
Eva-Maria Hubner1, Martin G Schmid1, Verina Manojlovic1
1Institute of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, University of Graz, Graz, Austria.
Magnetic resonance in chemistry : MRC
|January 2, 2025
概括
在线合成大麻素产品经常被错误标记,并且含有未经描述的物质. 这项研究从25个在线样本中确定了21种合成大麻素,包括新型化合物,突出了产品真实性和监管方面的重大问题.
科学领域:
- 法医化学 法医化学
- 药理学 药理学是指药理学的学科.
- 分析化学 分析化学
背景情况:
- 新型精神活性物质 (NPS),特别是合成大麻素,是全球快速增长的药物类别.
- 与传统的非法药物不同,合成大麻素通常在网上合法销售,这是由于其与控制物质如delta-9-tetrahydrocannabinol (Δ9-THC) 的结构差异.
- 这些物质经常被伪装成合法大麻产品,草药茶或其他植物材料,对消费者构成风险.
研究的目的:
- 为了识别和描述在线购买的合成大麻素样本.
- 为了生成实验数据,包括基于NMR的结构阐明,对于以前未被描述或记录不良的合成大麻素.
- 评估在线合成大麻素购买产品标签的准确性.
主要方法:
- 从各种在线供应商采购25个固态合成大麻素样本.
- 使用气体和液体色谱与质谱检测 (GC-MS/LC-MS) 的组合进行分析.
- 使用核磁共振 (NMR) 光谱学的结构阐明.
主要成果:
- 分析证实25个样本中的21个是合成大麻素.
- 在现有文献中,13种已识别的合成大麻素缺乏足够的实验性NMR数据.
- 一种新型合成大麻素CH-PIATA首次被识别和描述.
- 超过50%的采购样品被发现是错误申报的,这表明有广泛的错误标签.
结论:
- 合成大麻素在线供应广泛,通常标签不准确.
- 许多商业上可用的合成大麻素是新的或缺乏足够的特征,这给分析和监管带来了挑战.
- 该研究强调,迫切需要改进NPS的分析方法和监管监督,以确保公共安全.
相关概念视频
01:17Chemical Shift: Internal References and Solvent Effects
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In an NMR sample, precise measurement of the absolute absorption frequencies of nuclei is difficult. A standard internal reference compound is added, and the frequency difference between the reference signal and sample signals is measured.
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
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01:15NMR Spectroscopy: Chemical Shift Overview
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The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...
For instance, the proton...
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01:14NMR Spectroscopy of Aromatic Compounds
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Aromatic compounds can be identified or analyzed using proton NMR and carbon‐13 NMR. Typically, aromatic hydrogens or hydrogens directly bonded to the aromatic rings are strongly deshielded by the aromatic ring current. Therefore, they absorb in the range of 6.5–8.0 ppm in proton NMR spectra. For instance, aromatic hydrogens directly bonded to the benzene ring absorb at 7.3 ppm. However, aromatic hydrogens of larger rings absorb farther upfield or downfield than the ideal range.
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01:34NMR Spectroscopy of Benzene Derivatives
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Simple unsubstituted benzene has six aromatic protons, all chemically equivalent. Therefore, benzene exhibits only a singlet peak at δ 7.3 ppm in the 1H NMR spectrum. The observed shift is far downfield because the aromatic ring current strongly deshields the protons. Any substitution on the benzene ring makes the aromatic protons nonequivalent, and the protons split each other. The peak is, therefore, no longer a singlet and the splitting pattern and their associated coupling...
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01:15NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones
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Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
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