The Use of Single Crystal X-ray Diffraction Technique for Characterization of 25I-NBOMe and 25R-NBOH (R = Cl, I, Br, Et) in Forensic Application

Criminal minds create new psychoactive substances (NPS) to dribble the Drug Regulatory System. Early Warning Systems (EWA) were instituted worldwide to combat this practice. Brazilian government has started establishing EWA at a national level since August 2021. The role of drug analysis laboratories in EWA is very important and experts working at forensic laboratories are in the main position to detect NPS and any changes in the molecular structures. However, for this practice, it is necessary to use reliable analyses techniques for unequivocal identification. The goal of this work is to use single-crystal X-ray diffraction (XRD) to detect the presence of NPS and elucidate its molecular structure using single crystals from a seized blotter paper. XRD is also useful to prepare reference substances to produce entries to be included in Fourier transformed infrared spectroscopy (FTIR) and mass spectrometry databases, which are some of the most relevant routine techniques in forensic laboratories. This approach was used to study the NPS 25R-NBOH and 25I-NBOMe using XRD, FTIR, Raman, and nuclear magnetic resonance spectroscopies. The results showed that molecular structure methods must be used to elucidate NPS in an unambiguous manner and the potential of XRD use in the forensic area as a reference method.犯罪团伙制造新精神活性物质（new psychoactive substances，NPS）以规避药品监管体系。全球范围内已建立早期预警系统（Early Warning Systems，EWA）以打击此类行为。巴西政府自2021年8月起开始在国家层面搭建此类早期预警系统。药品分析实验室在早期预警系统中扮演着至关重要的角色，法医实验室的专家则是检测新精神活性物质及其分子结构变化的核心力量。然而，要开展此类检测工作，必须采用可靠的分析技术以实现明确的定性识别。本研究旨在借助单晶X射线衍射（single-crystal X-ray diffraction，XRD）技术，通过从缴获的吸墨纸中提取单晶，检测新精神活性物质的存在并阐明其分子结构。X射线衍射技术还可用于制备标准物质，为傅里叶变换红外光谱（Fourier transformed infrared spectroscopy，FTIR）和质谱数据库构建收录条目，而这两类技术正是法医实验室中最常用的常规检测手段之一。研究人员采用该方法，结合X射线衍射、傅里叶变换红外光谱、拉曼光谱以及核磁共振波谱技术，对新精神活性物质25R-NBOH和25I-NBOMe开展了研究。研究结果表明，必须借助分子结构表征方法才能对新精神活性物质进行明确的定性解析，同时也证实了X射线衍射技术作为参考方法在法医领域应用的潜力。