New cathinone‐derived designer drugs 3‐bromomethcathinone and 3‐fluoromethcathinone: studies on their metabolism in rat urine and human liver microsomes using GC–MS and LC–high‐resolution MS and their detectability in urine

Abstract

3-Bromomethcathinone (3-BMC) and 3-Fluoromethcathinone (3-FMC) are two new designer drugs, which were seized in Israel during 2009 and had also appeared on the illicit drug market in Germany. These two compounds were sold via the Internet as so-called "bath salts" or "plant feeders." The aim of the present study was to identify for the first time the 3-BMC and 3-FMC Phase I and II metabolites in rat urine and human liver microsomes using GC-MS and LC-high-resolution MS (HR-MS) and to test for their detectability by established urine screening approaches using GC-MS or LC-MS. Furthermore, the human cytochrome-P450 (CYP) isoenzymes responsible for the main metabolic steps were studied to highlight possible risks of consumption due to drug-drug interaction or genetic variations. For the first aim, rat urine samples were extracted after and without enzymatic cleavage of conjugates. The metabolites were separated and identified by GC-MS and by LC-HR-MS. The main metabolic steps were N-demethylation, reduction of the keto group to the corresponding alcohol, hydroxylation of the aromatic system and combinations of these steps. The elemental composition of the metabolites identified by GC-MS could be confirmed by LC-HR-MS. Furthermore, corresponding Phase II metabolites were identified using the LC-HR-MS approach. For both compounds, detection in rat urine was possible within the authors' systematic toxicological analysis using both GC-MS and LC-MS(n) after a suspected recreational users dose. Following CYP enzyme kinetic studies, CYP2B6 was the most relevant enzyme for both the N-demethylation of 3-BMC and 3-FMC after in vitro-in vivo extrapolation.

Benzofuran analogues of amphetamine and methamphetamine: studies on the metabolism and toxicological analysis of 5-APB and 5-MAPB in urine and plasma using GC-MS and LC-(HR)-MSn techniques

“…The loss of either acetamide or N-methyl-acetamide from the precursor ion resulted in ion at m/z 262, and the subsequent loss of one acetyl group and acetic acid then led to fragment ions at m/z 220 or 160, respectively. A b u n d a n t f r a g m e n t i o n s i n t h e s p e c t r u m o f peracetylated 3-dihydroxyethyl-4-hydroxy amphetamine (11) were at m/z 320, 278, and 218, resulting from subsequent loss of acetamide, acetyl group, and acetic acid from the side chain.…”

“…Conditions for the performance of the microsomal incubations for each isomer were published before [11]. Briefly, the drugs (150 μmol/L each) were incubated with the CYP isoenzymes (50 pmol/mL, each) CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, CYP3A5, or HLM (1 mg protein/mL) for 30 min.…”

“…The fragmentation patterns of other amphetamines or benzofurans [4,11] and the general fragmentation rules described by, e.g., Smith and Bush or McLafferty were taken into consideration [19,20]. Furthermore, the metabolism of other furan or benzofuran containing compounds was considered [21][22][23][24][25][26][27].…”

GC-MS, LC-MSn, LC-high resolution-MSn, and NMR studies on the metabolism and toxicological detection of mesembrine and mesembrenone, the main alkaloids of the legal high “Kanna” isolated from Sceletium tortuosum

“…Sample preparation of urine samples for metabolism studies using GC-MS For identification of phase I metabolites by GC-MS, 1 mL urine (rat urine after 20 mg/kg BW drug administration) was processed by enzymatic cleavage of conjugates and SPE (HCX) according to Reference [16]. Briefly, the enzymatic cleaved urine was loaded on an Isolute Confirm HCX cartridges previously conditioned with methanol and water.…”

Toxicology of Specific Substances

“…Furthermore cathinone-derived designer drugs like 3-bromomethcathinone (3-BMC) and 3-fluoromethcathinone (3-FMC) as well as β-keto amphetamines like mephedrone, butylone and methylone are of interest Meyer et al 2012).…”