Identification and chemical structure elucidation of synthetic cannabinoids samples seized in Kuwait during 2019-2023 using GC-MS and NMR spectroscopy.

Cannabinoids, a class of chemical compounds, interact with cannabinoid receptors and are categorized into endocannabinoids, phytocannabinoids, and synthetic cannabinoids (SCs) based on their origin. Among these, SCs constitute the largest and most structurally diverse group of novel psychoactive substances (NPS), with around 280 compounds identified globally. They exhibit a high binding affinity to cannabinoid receptors CB1 and CB2, which are distributed throughout the central nervous and immune systems, leading to more potent psychoactive and toxic effects compared with their natural counterparts. Various adverse effects associated with SCs include hypothermia, analgesia, catalepsy, psychosis, respiratory depression, cardiac arrest, nephrotoxicity, acute cerebral ischemia, seizures, and mortality. In a previous study, we reported the detection of several NPS in Kuwait using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry techniques. However, the identification was tentative, highlighting a limitation of these methods. To address this, the current study aimed to fully identify 17 seized SC samples. Thin-layer chromatography was initially employed to assess the purity of the samples. Twelve pure samples (AKM-1-AKM-12) underwent nuclear magnetic resonance analyses, including 1H, 13C, DEPT 45°, 90°, 135°, COSY, HSQC, and HMBC experiments. The identities of five samples (AKM-1, 5, 6, 8, 10) were confirmed as MDMB-4en-PINACA, one sample (AKM-2) as 4F-MDMB-BUTICA, one sample (AKM-3) as MPHP-2201, and three samples (AKM-4, 9, 11) as MMB-022. Additionally, two samples (AKM-7, 12) were identified as FUB-144. This comprehensive approach enhances the accuracy of SCs identification compared with previous studies, emphasizing the importance of employing nuclear magnetic resonance alongside other spectral methods for a more robust analysis.