Adding more "spice" to the pot: A review of the chemistry and pharmacology of newly emerging heterocyclic synthetic cannabinoid receptor agonists

Synthetic cannabinoid receptor agonists (SCRAs) first appeared on the international recreational drug market in the early 2000s in the form of SCRA-containing herbal blends. Due to the cannabimimetic effects associated with the consumption of SCRAs, they have acquired an ill-informed reputation for being cheap, safe, and legal alternatives to illicit cannabis. Possessing high potency and affinity for the human cannabinoid receptor subtype-1 (CB₁ ) and -2 (CB₂ ), it is now understood that the recreational use of SCRAs can have severe adverse health consequences. The major public health problem arising from SCRA use has pressed legislators around the world to employ various control strategies to curb their recreational use. To circumvent legislative control measures, SCRA manufacturers have created a wide range of SCRA analogs that contain, more recently, previously unencountered azaindole, γ-carbolinone, or carbazole heterocyclic scaffolds. At present, little information is available regarding the chemical syntheses of these newly emerging classes of SCRA, from a clandestine perspective. When compared with previous generations of indole- and indazole-type SCRAs, current research suggests that many of these heterocyclic SCRA analogs maintain high affinity and efficacy at both CB₁ and CB₂ but largely evade legislative control. This review highlights the importance of continued research in the field of SCRA chemistry and pharmacology, as recreational SCRA use remains a global public health issue and represents a serious control challenge for law enforcement agencies.

Four cases of death involving the novel synthetic cannabinoid 5F-Cumyl-PEGACLONE

Purpose

Cumyl-PEGACLONE was the first synthetic cannabinoid (SC) with a γ-carbolinone core structure detected in forensic casework and, since then, it has dominated the German SC-market. Here the first four cases of death involving its fluorinated analog, 5F-Cumyl-PEGACLONE, a recently emerged γ-carbolinone derived SC, are reported.

Methods

Complete postmortem examinations were performed. Postmortem samples were screened by immunoassay, gas chromatography mass spectrometry (GC–MS) or liquid chromatography tandem mass spectrometry. For quantification of SCs, the standard addition method was employed. Herbal blends were analyzed by GC–MS. In each case of death, the Toxicological Significance Score (TSS) was assigned to the compound.

Results

5F-Cumyl-PEGACLONE was identified at concentrations ranging 0.09–0.45 ng/mL in postmortem femoral blood. In case 1, signs of hypothermia and kidney bleedings were noted. Despite a possible tolerance due to long term SC use, a TSS of 3 was assigned. In case 2, an acute heroin intoxication occurred and a contributory role (TSS = 1) of 5F-Cumyl-PEGACLONE was suggested. In case 3, a prisoner was found dead. GC–MS analysis of herbal blends, retrieved in his cell together with paraphernalia, confirmed the presence of 5F-Cumyl-PEGACLONE and a causative role was deemed probable (TSS = 2). In case 4, the aspiration of gastric content due to a SC-induced coma was observed (TSS = 3).

Conclusions

5F-Cumyl-PEGACLONE is an emerging and extremely potent SC which raises serious public health concerns. A comprehensive analysis of circumstantial, clinical, and postmortem findings, as well as an in-depth toxicological analysis is necessary for a valid interpretation and for the assessment of the toxicological significance.