Metabolite Profiling of Rcs-4, A Novel Synthetic Cannabinoid Designer Drug, Using Human Hepatocyte Metabolism And TOF-MS

Abstract

Background Since 2009, scheduling legislation of synthetic cannabinoids prompted new compound emergence to circumvent legal restrictions. 2-(4-methoxyphenyl)-1-(1-pentyl-indol-3-yl)methanone (RCS-4) is a potent cannabinoid receptor agonist sold in herbal smoking blends. Absence of parent synthetic cannabinoids in urine suggests the importance of metabolite identification for detecting RCS-4 consumption in clinical and forensic investigations. Materials & methods & Results With 1 h human hepatocyte incubation and TOF high-resolution MS, we identified 18 RCS-4 metabolites, many not yet reported. Most metabolites were hydroxylated with or without demethylation, carboxylation and dealkylation followed by glucuronidation. One additional sulfated metabolite was also observed. O-demethylation was the most common biotransformation and generated the major metabolite. Conclusion For the first time, we present a metabolic scheme of RCS-4 obtained from human hepatocytes, including Phase I and II metabolites. Metabolite structural information and associated high-resolution mass spectra can be employed for developing clinical and forensic laboratory RCS-4 urine screening methods.

Metabolic patterns of JWH‐210, RCS‐4, and THC in pig urine elucidated using LC‐HR‐MS/MS: Do they reflect patterns in humans?

“…[4][5][6][7][8][9] For confirming the results of these in vitro studies, authentic human urine from clinical or forensic cases [10][11][12][13][14] can be used under the condition that the taken drug was known. [4][5][6][7][8][9] For confirming the results of these in vitro studies, authentic human urine from clinical or forensic cases [10][11][12][13][14] can be used under the condition that the taken drug was known.…”

“…IV, PM of m/z 514.2071) was identified by the fragment ions at m/z 135.0442, indicating an unaltered methoxyphenyl moiety, at m/z 144.0445, suggesting an unaltered indole moiety, and at m/z 264.1021, indicating a loss of a hydroxybutyl radical. [8] For hydroxy-methoxyphenyl-glucuronide (No. Again, considering differences between TOF and Orbitrap mass spectrometry systems, the results were in agreement with those found by Ghandi et al, [8] who identified RCS-4 phase I and II metabolites using human hepatocytes.…”

Metabolism and Bioactivation of The Tricyclic Antidepressant Amitriptyline in Human Liver Microsomes and Human Urine

“…Using this approach, 28 metabolites, including five NAC conjugates, were detected in human urine after an oral administration of 25 mg amitriptyline (Table 1). The proposed metabolic pathways of amitriptyline were shown in Mass spectral properties of amitriptyline Investigation and familiarization of the fragmentation behaviors of the parent compound is a prerequisite for structural identification of its potential metabolites using LC-MS/MS method, especially for idenfication of metabolites with high degree of structural similarity [34][35][36][37]. Only the positive ion mode was used for metabolites identification as the parent drug was a tertiary amine, and most metabolites contained an amine group but not carboxylic or phenolic group.…”

Structure–activity relationships of synthetic cannabinoid designer drug RCS-4 and its regioisomers and C4 homologues

“…RCS-4 is the most widely studied member of this class of SCs, and extensive metabolic profiling of RCS-4 has been reported [24][25][26][27]. Forensic chemists have also focused on the development of analytical methods for detection and quantification of RCS-4 and its metabolites in human hair [28], urine [29][30][31], serum [32], and oral fluid [33,34], with less attention given to RCS-2, and a complete dearth of information regarding the other RCS analogues.…”