合成大麻素类毒品的结构衍变与质谱解析

合成大麻素毒品蔓延趋势严峻，我国政府启动了整类列管政策。该类毒品结构变异较强，对重点目标结构的识别以及共性质谱特征的汇总在司法实践中具有重要意义。本文解析了该类毒品的结构衍变规律，遴选27种合成大麻素，采用气相色谱 质谱联用法（GC MS）采集EI MS数据。实验结果表明，合成大麻素类物质主要由母核、链接、取代基和侧链四部分构成。其中，吲哚/吲唑母核易产生m/z 144、145特征碎片；链接部分的碎裂主要发生在羰基两侧；取代基上的叔碳原子、丁酸甲酯以及丁酰胺易发生多元化碎裂；侧链易发生中性丢失而产生氟丁基（m/z 74）、氟戊基（m/z 88）和戊烯基（m/z 68）等特征碎片。该碎裂途径的推断可为未知新型合成大麻素类物质的判别提供参考。

Structural Development and Mass Spectrometry Analysis of Synthetic Cannabinoids

The abuse of new psychoactive substances has spread around the world. Synthetic cannabinoids (SCs) is an important group. Since the first discovery of JWH-018 in Europe in 2008, SCs have multiplied rapidly and become the focus of drug control worldwide. Statistics from the Drug Intelligence and Forensic Center of the Ministry of Public Security of China showed that the proportion of SCs in suspected drug samples seized had increased from 185% to 72% in 2017 2019. To this, our country drug control administration department makes positive response. A series of new anti drug policies had been introduced since 2015. Fifty three SCs were legally controlled until the end of 2018. China had issued total ban on SCs since July 1st, 2021. However, because of the great structural variability of SCs, it is of great significance to identify the key target structures and summarize the characteristics of the common spectrum of similar drugs in judicial practice. In this paper, 27 synthetic cannabinoids were selected, including the new synthetic cannabinoids with high prevalence in recent years and potential drug structures that had not been reported but were inferred based on the structural evolution trend of synthetic cannabinoids. The method of gas chromatography mass spectrometry (GC MS) was used to collect data of the selected SCs under electron ionization mode (EI). The results indicated that the SCs were mainly composed of core, linker, linked group and sidechain. Among them, the core of new SCs gradually changed from formyl indole to indole/indazolamide, which would produce characteristic fragments of m/z 144, 145, respectively. The fragmentation of the linker part mainly occurred on both sides of the carbonyl group. The tertiary carbon atoms, methyl butyrate and butylamide from the linked groups led to diversified fragmentation easily. Neutral loss frequently happened in the part of sidechain, which resulted in the formation of characteristic fragments such as fluoro butyl (m/z 74), fluoro pentyl (m/z 88) and pentenyl (m/z 68). The 7 SCs prepared according to the predicted structure shared similar fragmentation pathways with the 22 SCs abused both domestically and abroad. The variation of SCs based on the structures defined in law would gradually decrease and the structural stability would be enhanced after the total ban of SCs was issued. The mass fragmentation pathway mentioned above can provide technical support for the species identification of new SCs, as well as the prevention of drug variation.