Fragmentation of synthetic cannabinoids with an isopropyl group or a <i>tert</i>‐butyl group ionized by electron impact and electrospray

Synthetic cannabinoids have proliferated over the last decade and have become a major public health and analytical challenge, critically impacting the clinical and forensic communities. Indazole carboxamide class synthetic cannabinoids have been particularly rampant, and exhibit severe toxic effects upon consumption due to their high binding affinity and potency at the cannabinoid receptors (CB1 and CB2). MDMB‐CHMINACA, methyl 2‐[1‐(cyclohexylmethyl)‐1H‐indazole‐3‐carboxamido]‐3,3‐dimethylbutanoate, a compound of this chemical class, has been identified in forensic casework and is structurally related to several other synthetic cannabinoids. This study presents the first extensive report on the Phase I metabolic profile of MDMB‐CHMINACA, a potent synthetic cannabinoid. The in vitro metabolism of MDMB‐CHMINACA was determined via incubation with human liver microsomes and high‐resolution mass spectrometry. The accurate masses of precursor and fragments, mass error (ppm), and chemical formula were obtained for each metabolite. Twenty‐seven metabolites were identified, encompassing twelve metabolite types. The major biotransformations observed were hydroxylation and ester hydrolysis. Hydroxylations were located predominantly on the cyclohexylmethyl (CHM) moiety. Ester hydrolysis was followed by additional biotransformations, including dehydrogenation; mono‐ and dihydroxylation and ketone formation, each with dehydrogenation. Minor metabolites were identified and reported. The authors propose that CHM‐monohydroxylated metabolites specific to MDMB‐CHMINACA are the most suitable candidates for implementation into bioanalytical assays to demonstrate consumption of this synthetic cannabinoid. Due to the structural similarity of MDMB‐CHMINACA and currently trending synthetic cannabinoids whose metabolic profiles have not been reported, the results of this study can be used as a guide to predict their metabolic pathways.

Section: Resultssupporting

confidence: 56%

Section: Mdmb-chminacamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

Presley

Logan

Jansen‐Varnum

2019

“…EI-MS spectra of compounds (5, 11, 6, 12) determined by GC-MS. particular, the 2-adamantyl isomer of 5Cl-APINACA was shown in the list of NPS first notified in the Early Warning System in 2015, under the name of 5C-AKB48. Figure 5 shows EI-MS spectra of four adamantylindole carboxamide compounds (3,4,9,10). Figure 4 shows EI-MS spectra of four compounds (5,6,11,12).…”

Section: Resultsmentioning

confidence: 99%

“…Figure 4 shows EI-MS spectra of four compounds (5,6,11,12). [9,10] We next analyzed the 2-adamantyl isomers by GC-MS/MS to determine how these fragment ions arose. It was found that the fragmentation patterns showed similar trends to adamantylindazole carboxamide cannabinoids regardless of the type of alkyl groups bonded to the 1H-position of the indole or indazole.…”

Section: Resultsmentioning

confidence: 99%

Isomeric discrimination of synthetic cannabinoids by GC‐EI‐MS: 1‐adamantyl and 2‐adamantyl isomers of N‐adamantyl carboxamides

Asada

Doi

Tagami

et al. 2016

N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA) and N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA) are carboxamide-type synthetic cannabinoids comprising indazole/indole-3-carboxylic acid and adamantan-1-amine moieties. However, in the case of compounds like APINACA or APICA, adamantyl positional isomers exist, wherein either adamantan-1-amine or adamantan-2-amine is present. These adamantyl positional isomers have not been reported in previous studies, and no analytical data are available. To avoid misidentification of adamantyl carboxamide-type synthetic cannabinoids, it is important to develop methods to discriminate these adamantyl positional isomers. In this study, we report the analytical characterization by gas chromatography-electron ionization-mass spectrometry (GC-EI-MS). For providing analytical standards, we synthesized eight carboxamide-type synthetic cannabinoids (APINACA 2-adamantyl isomer, APICA 2-adamantyl isomer, 5 F-APINACA 2-adamantyl isomer, 5 F-APICA 2-adamantyl isomer, 5Cl-APINACA, 5Cl-APINACA 2-adamantyl isomer, adamantyl-THPINACA, 2-adamantyl-THPINACA) and purchased four 1-adamantyl derivatives (APINACA, APICA, 5 F-APINACA, 5 F-APICA). Although the retention times of the isomers are similar, 1-adamantyl carboxamides can be clearly discriminated from their 2-adamantyl isomers based on their different fragmentation patterns in the EI-MS spectra. Specifically, EI-MS spectra for adamantylindazole carboxamides showed remarkable differences between the 1-adamantyl and 2-adamantyl isomers. On the other hand, EI-MS spectra for adamantylindole carboxamides were similar, but the diagnostic ions of the 2-adamantyl isomers were observed. The method described herein was applicable to all compounds tested in this study and is expected to be of use for isomeric differentiation between other untested adamantyl carboxamide-type synthetic cannabinoids. Copyright © 2016 John Wiley & Sons, Ltd.

“Walking the nitrogen around the ring”: Chemical synthesis and spectroscopic characterization of novel 4‐, 5‐, 6‐, and 7‐azaindazole analogs of the synthetic cannabinoid receptor agonist MDMB‐PINACA

Alam

Keating

2021

Over the past decade, synthetic cannabinoid receptor agonists (SCRAs) have rapidly evolved to encompass a wide range of structurally diverse new psychoactive substances (NPS), including derivatives that incorporate indole, indazole, 7-azaindole, γ-carbolinone, or carbazole heterocyclic scaffolds. The introduction of legislative measures seeking to control the availability of NPS on the recreational drug scene has likely contributed to the continued emergence of novel SCRA analogs, which often evade regulatory control. However, the detection and/or identification of azaindazole-type SCRAs in seized material has not yet been reported . It is plausible that SCRAs bearing a 1,3-disubstituted azaindazole scaffold may possess cannabimimetic activity, given their structural similarity with known indole, indazole, and azaindole SCRAs. In view of these antecedents, a set of four novel isomeric 4-, 5-, 6-, and 7-azaindazole analogs of the known potent indazole SCRA, MDMB-PINACA, were synthesized using a Pd-catalyzed aminocarbonylation strategy. The complementary use of ultraviolet (UV) and infrared (IR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), high resolution mass spectrometry (HRMS), 1D-and 2D-nuclear magnetic resonance (NMR) spectroscopy, and high performance liquid chromatography (HPLC) has permitted the spectroscopic differentiation, unambiguous structural assignment, and rapid separation of novel isomeric 4-, 5-, 6-, and 7-azaindazole analogs of the indazole SCRA, MDMB-PINACA.