Skip to content

Bronislav Jurásek

15 papers in the library · 94 citations · publishing 2017-2026

Papers

Synthesis, absolute configuration and in vitro cytotoxicity of deschloroketamine enantiomers: rediscovered and abused dissociative anaesthetic

New Journal of Chemistry January 1, 2018 Bronislav Jurásek, František Králík, Silvie Rimpelová et al. 15 citations

The dissociative drug deschloroketamine was synthesized, and the absolute configuration of its enantiomers was determined. The in vitro cytotoxicity of each enantiomer was tested across nine different cell lines, providing data on their relative toxicities.

2C-B-Fly-NBOMe Metabolites in Rat Urine, Human Liver Microsomes and C. elegans: Confirmation with Synthesized Analytical Standards.

Metabolites November 12, 2021 Jitka Nykodemová, Anna Šuláková, Petr Palivec et al. 14 citations

The metabolism of the psychoactive compound 2C-B-Fly-NBOMe was investigated using three systems: human liver microsomes, the fungus Cunninghamella elegans, and live rats. Thirty-five phase I and nine phase II metabolites were identified. Major metabolic pathways include hydroxylation, O-demethylation, oxidative debromination, and N-demethoxybenzylation, followed by glucuronidation or N-acetylation. Human liver microsomes produced the most metabolites at highest concentrations. Two poly-hydroxylated metabolites appeared only in rat urine, while the fungus generated dehydrogenated, N-oxygenated, and dibrominated metabolites. These findings clarify how the body processes this substance, aiding understanding of its effects and potential toxicity.

Pharmacokinetic, pharmacodynamic, and behavioural studies of deschloroketamine in Wistar rats.

British journal of pharmacology January 1, 2022 Kristýna Štefková-mazochová, Hynek Danda, Wim Dehaen et al. 13 citations

Deschloroketamine (DCK), a structural analogue of ketamine sold as a recreational drug, was tested in Wistar rats to examine its pharmacokinetics, acute effects, and addictive potential. DCK rapidly entered the brain, with peak levels at 30 minutes and sustained high levels for 2 hours. It blocks NMDA receptors similarly to ketamine, with the S-enantiomer more potent. DCK stimulated locomotion, induced place preference (a sign of reward), and strongly disrupted prepulse inhibition (PPI). Locomotor stimulation faded faster than PPI disruption. S-DCK had stronger stimulatory effects than R-DCK, but both equally disrupted PPI. DCK's behavioral and addictive profiles resemble ketamine's, with a slightly slower clearance, matching its reported longer duration. These findings clarify risks of illicit DCK use.

Synthesis of methoxetamine, its metabolites and deuterium labelled analog as analytical standards and their HPLC and chiral capillary electrophoresis separation

RSC Advances January 1, 2017 Bronislav Jurásek, Michal Himl, Radek Jurok et al. 13 citations

Methoxetamine, a designer drug sold as a substitute for the dissociative anesthetic ketamine, has been linked to numerous hospital intoxications and deaths across Europe.

Synthesis and identification of deschloroketamine metabolites in rats' urine and a quantification method for deschloroketamine and metabolites in rats' serum and brain tissue using liquid chromatography tandem mass spectrometry

Drug Testing and Analysis October 31, 2019 Kateřina Hájková, Bronislav Jurásek, Jan Čejka et al. 12 citations

Deschloroketamine, a ketamine analog sold illicitly since 2015 and sometimes misrepresented as ketamine, has potential antidepressant properties. A metabolomics study used liquid chromatography–high-resolution mass spectrometry and a validated multiple reaction monitoring method to track its metabolites in urine, serum, and brain tissue. Key metabolites—trans-dihydrodeschloroketamine, cis- and trans-dihydronordeschloroketamine, and nordeschloroketamine—were synthesized and used as standards. In serum, nordeschloroketamine and deschloroketamine concentrations ranged from 0.5 to 860 ng/mL; in brain tissue, they ranged from 0.5 to 4700 ng/g. The quantification methods showed intra-day accuracy of 80–125% and precision averaging 3–7%.

Intriguing Cytotoxicity of the Street Dissociative Anesthetic Methoxphenidine: Unexpected Impurities Spotted

International Journal of Molecular Sciences February 14, 2022 Bronislav Jurásek, Silvie Rimpelová, Martin Babor et al. 7 citations

A sample of the dissociative anesthetic methoxphenidine from the black market contained an unusual bromo- and chloro-zincate anion impurity. In vitro cytotoxicity tests on kidney, liver, and bladder cell lines showed that the street sample was markedly more toxic than a pure methoxphenidine standard, suggesting the impurity caused the increased toxicity. A method using X-ray powder diffraction (XRPD) was developed to identify such anions and distinguish different crystalline forms of methoxphenidine, providing additional data not captured by routine analysis.

A structural spectroscopic study of dissociative anaesthetic methoxphenidine

New Journal of Chemistry January 1, 2023 Bronislav Jurásek, Patrik Fagan, Bohumil Dolenský et al. 6 citations

Methoxphenidine, a dissociative anesthetic related to phencyclidine, was originally patented for its potential to treat neurotoxic injury. The abstract indicates that the compound was developed with therapeutic applications in mind, specifically for addressing damage to the nervous system. No further details about its efficacy, mechanism, or clinical use are provided in this text.

X-ray powder diffraction data for ( S )-Deschloroketamine hydrochloride, C 13 H 18 ClNO

Powder Diffraction June 21, 2017 J. Maixner, Bronislav Jurásek, Michal Kohout et al. 5 citations

The crystal structure of S-2-(methylamino)-2-phenylcyclohexan-1-one hydrochloride (C13H18ClNO) was determined using X-ray powder diffraction. The compound crystallizes in the monoclinic space group P21 with unit-cell parameters a = 6.578 Å, b = 13.250 Å, c = 15.096 Å, β = 91.619°, and a unit-cell volume of 1315 ų, with four formula units per cell. All measured diffraction lines were indexed and are consistent with the assigned space group, and no detectable impurities were observed in the sample.

The acute effects of methoxphenidine on behaviour and pharmacokinetics profile in animal model.

Progress in neuro-psychopharmacology & biological psychiatry March 20, 2025 Kristýna Štefková-mazochová, Hynek Danda, Vladimír Mazoch et al. 3 citations

Methoxphenidine (MXP), a new psychoactive substance, rapidly crosses the blood-brain barrier in Wistar rats, reaching peak concentrations in serum and brain 30 minutes after injection, with a half-life of 2.15 hours. Low to moderate doses (10-20 mg/kg) increase locomotor activity in an open field test, while a higher dose (40 mg/kg) decreases it. All doses disrupt sensorimotor gating (prepulse inhibition), an effect linked to psychosis. MXP shows moderate acute toxicity with an estimated LD50 of 500 mg/kg subcutaneously. The drug exhibits a profile similar to dissociative anesthetics, producing stimulant and anxiogenic effects at lower doses and sedative effects at higher doses, indicating risks of serious adverse health outcomes from recreational use.

Preliminary pharmacokinetic and psychophysical investigations after controlled oral and inhalative consumption of hexahydrocannabinol (HHC)

Scientific Reports March 24, 2025 Lisa Höfert, Benjamin Franz, Cedric Groß et al. 2 citations

After oral (25 mg fruit gum) or inhalative (three puffs from a vape) consumption of the semi-synthetic cannabinoid hexahydrocannabinol (HHC), its pharmacokinetics and psychoactive effects are comparable to those of tetrahydrocannabinol (THC). The route of administration and inter-individual factors strongly influence maximum concentrations, pharmacokinetic profiles, and the subjective 'high' feeling. Serum, urine, and saliva samples were analyzed for HHC and its metabolites. Three commercially available immunological tests were also evaluated for detectability.

X-ray powder diffraction data for methoxetamine hydrochloride, C 15 H 22 ClNO 2

Powder Diffraction August 22, 2017 J. Maixner, Bronislav Jurásek, Michal Himl et al. 2 citations

The X-ray powder diffraction pattern of 2-(ethylamino)-2-(3-methoxyphenyl)cyclohexan-1-one hydrochloride is reported, providing its unit-cell parameters and space group. The compound crystallizes in the monoclinic space group P21 with two molecules per unit cell. All observed diffraction lines were indexed and matched this space group, and no impurities were detected.

Behavioural and pharmacological evaluation of the psilocybin analogue baeocystin in Wistar rats.

Progress in neuro-psychopharmacology & biological psychiatry July 5, 2025 Hynek Danda, Kristýna Mazochová, Klára Šíchová et al. 1 citation

Baeocystin, a compound found in psychoactive mushrooms, has minimal to no behavioral effects in rats, likely because it poorly crosses the blood-brain barrier. After subcutaneous doses of 1.25 or 5 mg/kg, baeocystin and its metabolite norpsilocin showed very limited brain penetration. Consistent with this, the compound had no significant effects on locomotor activity, exploratory behavior, anxiety-like responses, or sensorimotor gating in Wistar rats. The findings suggest baeocystin's negligible neurobiological and psychedelic activity is due to its poor permeability across the blood-brain barrier.

Achiral LC-MS/MS and chiral SFC-MS methods for quantification of methoxphenidine and O-desmethyl-methoxphenidine metabolite in rat serum and brain.

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences June 1, 2025 Natalie Paškanová, Magdaléna Vágnerová, Bronislav Jurásek et al. 1 citation

Methoxphenidine (MXP), a dissociative anaesthetic derivative, is increasingly abused, but forensic and clinical data on its metabolism and enantiomers are limited. Researchers developed and validated achiral LC-MS/MS and chiral SFC-MS methods to quantify MXP and its primary metabolite, O-desmethyl-methoxphenidine (dmMXP), in rat serum and brain after a single subcutaneous dose of racemic MXP. Serum MXP peaked at 1600 ng/mL at 0.5 hours and decreased to 5.87 ng/mL at 24 hours; brain MXP peaked at 13200 ng/g at 0.5 hours and fell to 36.1 ng/g at 24 hours. (S)-MXP concentrations in brain appeared higher than (R)-enantiomer concentrations. The methods enable pharmacokinetic studies and provide tools for forensic and clinical toxicology.

Metabolic profile of 25E-NBOH in human liver microsomes, rat urine, and fungus Cunninghamella elegans.

Journal of pharmaceutical and biomedical analysis August 1, 2026 Magdaléna Vágnerová, Petr Palivec, Monika Mrňavá et al.

The metabolism of the recreational drug 25E-NBOH was investigated in human liver microsomes, rat urine, and Cunninghamella elegans fungus. Using untargeted LC-HRMS/MS, 56 metabolites were annotated, many as isomers. Primary metabolic pathways included hydroxylation, O-demethylation, and N-debenzylation, followed by conjugation. Ten reference substances were synthesized; seven matched detected metabolites by retention time and MS/MS spectra, enabling structural assignment. The known psychoactive substance 2C-E was confirmed as a metabolite. Three main biomarkers are proposed. This work provides the first comprehensive metabolic profile of 25E-NBOH, supporting future pharmacological and toxicological studies and aiding clinical diagnosis of intoxication.

The crystal structures of methoxmetamine hydrochloride and methoxetamine hydrochloride determined from laboratory X-ray powder diffraction data contained in the Powder Diffraction File ™

Powder Diffraction December 1, 2025 Analio Dugarte-Dugarte, Jacco van de Streek, Graciela Dı́az de Delgado et al.

The crystal structures of two arylcyclohexylamine derivatives, methoxmetamine hydrochloride (MMXE·HCl) and methoxetamine hydrochloride (MXE·HCl), were determined using laboratory X-ray powder diffraction data. Both compounds are known for anesthetic and sedative effects and have been used illicitly as recreational drugs. Structure determination was performed with DASH software and Rietveld refinements with TOPAS Academic, yielding monoclinic unit cells. For MMXE·HCl, the parameters were a = 15.0429(5) Å, b = 14.0721(5) Å, c = 6.5716(2) Å, β = 90.9864(14)°, V = 1,390.91(8) ų, with Z = 4 and space group P2₁/n. For MXE·HCl, the parameters were a = 8.7772(5) Å, b = 9.9528(7) Å, c = 8.5841(6) Å, β = 100.276(3)°, V = 737.