Metabolic fate of the new synthetic cannabinoid 7’N‐5F‐ADB in rat, human, and pooled human S9 studied by means of hyphenated high‐resolution mass spectrometry

Abstract

New psychoactive substances (NPS) are an important issue in clinical/forensic toxicology. 7'N-5F-ADB, a synthetic cannabinoid derived from 5F-ADB, appeared recently on the market. Up to now, no data about its mass spectral fragmentation pattern, metabolism, and thus suitable targets for toxicological urine screenings have been available. Therefore, the aim of this study was to elucidate the metabolic fate of 7'N-5F-ADB in rat, human, and pooled human S9 (pS9). The main human urinary excretion products, which can be used as targets for toxicological screening procedures, were identified by Orbitrap (OT)-based liquid chromatography-high resolution-tandem mass spectrometry (LC-HRMS/MS). In addition, possible differentiation of 7'N-5F-ADB and 5F-ADB via LC-HRMS/MS was studied. Using the in vivo and in vitro models for metabolism studies, 36 metabolites were tentatively identified. 7'N-5F-ABD was extensively metabolized in rat and human with minor species differences observed. The unchanged parent compound could be found in human urine but metabolites were far more abundant. The most abundant ones were the hydrolyzed ester (M5), the hydrolyzed ester in combination with hydroxylation of the tertiary butyl part (M11), and the hydrolyzed ester in addition to glucuronidation (M30). Besides the parent compound, these metabolites should be used as targets for urine-based toxicological screening procedures. Two urine-paired human plasma samples contained mainly the parent compound (c = 205 μg/L, 157 μg/L) and, at a higher abundance, the compound after ester hydrolysis (M5). In pS9 incubations, the parent compound, M5, and M30 were detectable among others. Furthermore, a differentiation of both compounds was possible due to different retention times and fragmentation patterns.

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

“…Although several studies have examined the metabolic fate of indole and indazole SCRAs, only a limited number of publications have investigated the metabolism of newly emerging azaindole SCRAs. A metabolic study of the azaindole SCRA, 5F‐MDMB‐P7AICA ( 25 ), was carried out by Richter et al, using rat urine, authentic human urine (and plasma), and pooled human liver S9 fraction (a mixture of endogenous cytosolic and microsomal components) . The latter study found that 25 undergoes extensive phase I metabolism to give over 36 structurally distinct metabolites.…”

“…The latter study found that 25 undergoes extensive phase I metabolism to give over 36 structurally distinct metabolites. Importantly, the three most abundant metabolites of 25 , found in human urine, were acid 57 (the ester hydrolysis product of 25 ), 58 ( 56 which has undergone additional aliphatic hydroxylation at its tert ‐butyl substituent), and 59 (the phase II acyl glucuronide metabolite of 56 ) (Figure ) . Staeheli et al have identified a number of metabolites in human urine samples, following the consumption of 5F‐CUMYL‐P7AICA ( 19 ).…”

1H−15N HMBC NMR as a tool for rapid identification of isomeric azaindoles: The case of 5F‐MDMB‐P7AICA

“…Briefly, the 5F code denotes 5‐F luoro tail substituent, MDMB part is a code derived from M ethyl 3,3‐ D i M ethyl B utanoate (linked group), P refers to the P entyl (tail), 7 AI is derived from 7‐ A za I ndole (core), and CA represents the C arbox A mide (linker). For the same compound the notation 7’N 5F‐ADB was recently applied in the literature …”

“…Based on the literature report, it can be expected that 5F‐MDMB‐P7AICA ( 1 ) is active but less potent than its constitutional isomer 5F‐MDMB‐PINACA . A study of the in vitro metabolic profile of 5F‐MDMB‐P7AICA ( 1 ) (7’N‐5F‐ADB) has been published recently …”

“…For the same compound the notation 7'N 5F-ADB was recently applied in the literature. 9 The identification of a new compound is a challenge in forensic work due to the absence of reliable scientific data, validated spectral libraries, and a lack of reference materials, which are not available in real time.…”