In vitro metabolism of the synthetic cannabinoids CUMYL‐PINACA, 5F–CUMYL‐PINACA, CUMYL‐4CN‐BINACA, 5F–CUMYL‐P7AICA and CUMYL‐4CN‐B7AICA

Abstract

Synthetic cannabinoid consumption trends underlie fast changes and provide several challenges to clinical and forensic toxicologists. Due to their extensive metabolism, parent compounds are hardly detectable in urine. Therefore, knowledge of the metabolism of synthetic cannabinoids is essential to allow their detection in biological matrices. The aim of the present study was the elucidation of the metabolism of CUMYL-PINACA, 5F-CUMYL-PINACA, CUMYL-4CN-BINACA, 5F-CUMYL-P7AICA, and CUMYL-4CN-B7AICA with a focus on the analytical and interpretational differentiation of the compounds. Microsomal assay mixtures containing cosubstrates, 10 μg/mL substrate and 1 mg/mL pooled human liver microsomes were incubated for 1 hour at 37°C. Investigation of the metabolites was performed on a Thermo Fischer Ultimate 3000 UHPLC system coupled to a Sciex 6600 QTOF System. Hydroxylation was observed to be a major biotransformation step for all 5 cumyl-derivatives, followed by dihydroxylation.For CUMYL-PINACA, a major metabolic pathway was hydroxylation at the pentyl moiety, followed by a second hydroxylation at that pentyl moiety or oxidation to ketone. A major metabolic pathway for the compounds containing a nitrile function was nitrile hydrolysis followed by carboxylation and further hydroxylation. For the fluorinated compounds, oxidative defluorination and carboxylation were abundant metabolic steps. Some of the metabolic transformations lead to structurally identical metabolites, which should not be used as marker for the intake of a particular parent compound. In addition, several constitutional isomers containing either an indazole or azaindole core structure were detected, which should be differentiated by retention time rather than by their mass spectra alone. KEYWORDSin vitro metabolism, new psychoactive substances NPS, synthetic cannabinoids

Phase I metabolism of the recently emerged synthetic cannabinoid CUMYL‐PEGACLONE and detection in human urine samples

“…Phase I metabolism studies revealed that CUMYL‐PEGACLONE is an extensively metabolized SC. In contrast to former cumyl‐derivatives, the main in vivo metabolite M20 was unexpectedly hydroxylated at the γ ‐carbolinone core whereas former analogs were mainly hydroxylated at the pentyl side chain . The metabolites M20 and M09 were identified as sensitive and specific urinary markers to proof uptake of this highly prevalent substance.…”

In vitro Phase I metabolism of indazole carboxamide synthetic cannabinoid MDMB‐CHMINACA via human liver microsome incubation and high‐resolution mass spectrometry

“…The metabolism of many synthetic cannabinoids has been determined via HLM incubations . The findings reported in the current study contributes to the body of knowledge available on indazole carboxamide synthetic cannabinoid metabolism via HLM incubations.…”

“…The in vitro and in vivo metabolic profiles of several indazole carboxamide synthetic cannabinoids have been reported . In this study the in vitro metabolic profile of indazole carboxamide synthetic cannabinoid, MDMB‐CHMINACA, was determined.…”

Metabolism study for CUMYL‐4CN‐BINACA in human hepatocytes and authentic urine specimens: Free cyanide is formed during the main metabolic pathway

“…Among the metabolites reported here, the N ‐dealkylated metabolite (M9) was the only one unique to the hepatocyte data. Overall, our results are also in agreement with previous findings and complement the work of Öztürk et al and Staeheli et al We detected the same main metabolite, CUMYL‐BINACA carboxylic acid (M10), and the same hydroxylated metabolites (M2, M7) as these 2 research groups.…”

“…A few metabolism studies have been performed for CUMYL‐4CN‐BINACA: Öztürk et al paired results from a human liver microsome (HLM) experiment with 80 urine samples from suspected drug users and suggested 3 metabolites as urinary biomarkers, 2 monohydroxylated metabolites, and CUMYL‐BINACA butanoic acid . Staeheli et al investigated the metabolism of CUMYL‐4CN‐BINACA and other cumyl‐containing synthetic cannabinoids in HLM and reported nitrile hydrolysis with and without further hydroxylation as well as hydroxylation of the aryl moiety as major biotransformations …”