Metabolic profiling of synthetic cannabinoid 5F‐ADB by human liver microsome incubations and urine samples using high‐resolution mass spectrometry

Abstract

5F‐ADB (methyl 2‐{[1‐(5‐fluoropentyl)‐1H‐indazole‐3‐carbonyl] amino}‐3,3‐dimethylbutanoate) is a frequently abused new synthetic cannabinoid that has been sold since at least the end of 2014 on the drug market and has been classified as an illicit drug in most European countries, as well as Turkey, Japan, and the United States. In this study, the in vitro metabolism of 5F‐ADB was investigated by using pooled human liver microsomes (HLMs) assay and liquid chromatography‐high‐resolution mass spectrometry (LC–HRMS). 5F‐ADB (5 μmol/L) was incubated with HLMs for up to 3 hours, and the metabolites were identified using LC–HRMS and software‐assisted data mining. The in vivo metabolism was investigated by the analysis of 30 authentic urine samples and was compared to the data received from the in vitro metabolism study. Less than 3.3% of the 5F‐ADB parent compound remained after 1 hour of incubation, and no parent drug was detected after 3 hours. We identified 20 metabolites formed via ester hydrolysis, N‐dealkylation, oxidative defluorination, hydroxylation, dehydrogenation, further oxidation to N‐pentanoic acid and glucuronidation or a combination of these reactions in vitro. In 12 urine samples (n = 30), 5F‐ADB was detected as the parent drug. Three of the identified main metabolites 5F‐ADB carboxylic acid (M20), monohydroxypentyl‐5F‐ADB (M17), and carboxypentyl ADB carboxylic acid (M8) were suggested as suitable urinary markers. The screening of 8235 authentic urine samples for identified 5F‐ADB metabolites in vitro resulted in 3135 cases of confirmed 5F‐ADB consumption (38%).

In vitro metabolism of the synthetic cannabinoids PX‐1, PX‐2, and PX‐3 by high‐resolution mass spectrometry and their clearance rates in human liver microsomes

“…Two common fragments, m/z 144 and m/z 232, observed in PX‐1 and similar PICA SCs are characteristic of the indole core and fluoropentyl tail . The fragments m/z 145, 233, and 213 were observed in the elucidation of PX‐2 and other PINACA compounds and are characteristic of the indazole core and fluoropentyl tail . The most common fragments m/ z 145, 257, and 241 observed in PX‐3 and other CHMINACA SCs are characteristic of the indazole core and cyclohexylmethyl tail.…”

Phase I metabolism of synthetic cannabinoid receptor agonist PX‐1 (5F‐APP‐PICA) via incubation with human liver microsomes and UHPLC–HRMS

“…The reports are complementary and demonstrate the usefulness of both HLM and human hepatocyte incubation processes in determining the metabolic profiles of synthetic cannabinoids. HLMs are a more cost‐effective option for in vitro metabolism studies, and have been successfully applied to the determination of many synthetic cannabinoids (Erratico et al, ; Franz et al, ; Thomsen et al, ; Yeter & Erol Öztürk, ).…”

“…Other synthetic cannabinoids containing fluoropentyl side chains whose in vitro and/or in vivo metabolic profile has been reported include AM‐2201, 5F‐ADB, 5F‐MDMB‐PICA, EG‐2201, and 5F‐CUMYL‐PEGACLONE (Figure ; Center for Forensic Science Research and Education, , ; Chimalakonda et al, ; Diao, Carlier, Zhu, & Huestis, ; Ernst, Langer, Bockelmann, Salkhordeh, & Beuerle, ; Hutter et al, ; Jang et al, ; Mogler et al, ; Mogler, Halter, Wilde, Franz, & Auwärter, ; Risseeuw et al, ; Sobolevsky et al, ; Yeter & Erol Öztürk, ). Structural differences exist between these compounds and PX‐1.…”

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.…”