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https://www.readbyqxmd.com/read/28092216/metabolism-of-metofluthrin-in-rats-i-identification-of-metabolites
#1
Jun Abe, Hirohisa Nagahori, Hirokazu Tarui, Yoshitaka Tomigahara, Naohiko Isobe
Metofluthrin (2,3,5,6-tetrafluoro-4-(methoxymethyl)benzyl (Z/E)-(1R)-trans-2,2-dimethyl-3-(1-propenyl)-cyclopropanecarboxylate) is a novel pyrethroid insecticide, which has E/Z isomers at prop-1-enyl group. Rats were orally dosed with each [(14)C]-labeled E/Z isomer, and the excreta were collected for isolation and identification of metabolites. Analysis of the excreta by LC/MS and NMR revealed formation of 33 and 23 (total 42) metabolites from rats dosed with Z-isomer and E-isomer, respectively. Major metabolic reactions were cleavage of ester linkage, O-demethylation, hydroxylation, epoxidation or reduction of double bond, glutathione conjugation and its further metabolism, hydroxylation of epoxide, and formation of lactone ring...
January 16, 2017: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/28010169/consequences-of-daily-corticosteroid-dosing-with-or-without-pre-treatment-with-quinidine-on-the-in-vivo-cytochrome-p450-2d-cyp2d-enzyme-in-rats-effect-on-o-demethylation-activity-of-dextromethorphan-and-expression-levels-of-cyp2d1-mrna
#2
Poonam Giri, Prashant Delvadia, Laxmikant Gupta, Nirmal Patel, Priyal Trivedi, Krishna Lad, Hiren M Patel, Nuggehally R Srinivas
1. Present investigation was carried out in rats to study influence of corticosteroids after repeated dosing with/without pre-treatment with CYP2D inhibitor quinidine on the CYP2D1 mRNA levels and CYP2D enzyme activity using dextromethorphan as probe substrate. 2. CYP2D1 mRNA was measured in liver homogenate using quantitative real-time polymerase chain reaction [qRT-PCR] and enzymatic reaction was studied ex vivo in liver S-9 fractions of rats treated with oral 10 mg/kg dexamethasone or prednisolone for five days or pre-treated with quinidine and followed by treatment with oral 10 mg/kg corticosteroids for five days...
January 19, 2017: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/27966376/production-of-17-o-demethyl-geldanamycin-a-cytotoxic-ansamycin-polyketide-by-streptomyces-hygroscopicus-dem20745
#3
Aron Baksh, Bernhard Kepplinger, Hadiza A Isah, Michael R Probert, William Clegg, Corinne Wills, Michael Goodfellow, Jeff Errington, Nick Allenby, Michael J Hall
The actinomycete DEM20745, collected from non-rhizosphere soil adjacent to Paraserianthes falactaria trees (Cangkringan, Indonesia), is an efficient producer of the anticancer ansamycin polyketide 17-O-demethyl-geldanamycin (17-O-DMG), a biosynthetic precursor of the Hsp90 inhibitor geldanamycin (GDM). In DEM20745, 17-O-DMG is the major ansamycin product observed reaching a maximum titre of 17 mg/L in the fermentation broth. 17-O-DMG has the potential to be a key starting material for the semi-synthesis of GDM analogues for use in anticancer therapy...
December 14, 2016: Natural Product Research
https://www.readbyqxmd.com/read/27915193/metabolic-fate-and-detectability-of-the-new-psychoactive-substances-2-4-bromo-2-5-dimethoxyphenyl-n-2-methoxyphenyl-methyl-ethanamine-25b-nbome-and-2-4-chloro-2-5-dimethoxyphenyl-n-2-methoxyphenyl-methyl-ethanamine-25c-nbome-in-human-and-rat-urine-by-gc-ms
#4
Achim T Caspar, Simon D Brandt, Andreas E Stoever, Markus R Meyer, Hans H Maurer
25B-NBOMe and 25C-NBOMe are potent 5-HT2A receptor agonists that have been associated with inducing hallucinogenic effects in drug users and severe intoxications. This paper describes the identification of their metabolites in rat and human urine by liquid chromatography (LC)-high resolution (HR)-MS/MS, the comparison of metabolite formation in vitro and in vivo and in different species, the general involvement of human cytochrome-P450 (CYP) isoenzymes on their metabolism steps, and their detectability by standard urine screening approaches (SUSAs) using GC-MS, LC-MS(n), or LC-HR-MS/MS...
February 5, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27862205/antioxidant-activity-acetylcholinesterase-and-carbonic-anhydrase-inhibitory-properties-of-novel-ureas-derived-from-phenethylamines
#5
Kadir Aksu, Bünyamin Özgeriş, Parham Taslimi, Ali Naderi, İlhami Gülçin, Süleyman Göksu
A series of ureas derived from phenethylamines were synthesized and evaluated for human carbonic anhydrase (hCA) I and II, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzyme inhibitory activities and antioxidant properties. The ureas were synthesized from the reactions of substituted phenethylamines with N,N-dimethylcarbamoyl chloride; then, the synthesized compounds were converted to their corresponding phenolic derivatives via O-demethylation. hCA I and II were effectively inhibited by the newly synthesized compounds, with Ki values in the range of 0...
December 2016: Archiv der Pharmazie
https://www.readbyqxmd.com/read/27861439/trends-in-tramadol-pharmacology-metabolism-and-misuse
#6
Karen Miotto, Arthur K Cho, Mohamed A Khalil, Kirsten Blanco, Jun D Sasaki, Richard Rawson
Tramadol is a unique analgesic medication, available in variety of formulations, with both monoaminergic reuptake inhibitory and opioid receptor agonist activity increasingly prescribed worldwide as an alternative for high-affinity opioid medication in the treatment of acute and chronic pain. It is a prodrug that is metabolized by cytochrome P450 (CYP) enzymes CYP2D6 and CYP3A4 to its more potent opioid analgesic metabolites, particularly the O-demethylation product M1. The opioid analgesic potency of a given dose of tramadol is influenced by an individual's CYP genetics, with poor metabolizers experiencing little conversion to the active M1 opioid metabolite and individuals with a high metabolic profile, or ultra-metabolizers, experiencing the greatest opioid analgesic effects...
January 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/27831926/biodegradation-of-micropollutant-naproxen-with-a-selected-fungal-strain-and-identification-of-metabolites
#7
Y Doruk Aracagök, Hakan Göker, Nilüfer Cihangir
Pharmaceuticals are widely used for treating human and animal diseases. Naproxen [(S) 6-methoxy-α-methyl-2-naphthalene acetic acid] and its sodium salt are members of the α-arylpropionic acid group of nonsteroidal anti-inflammatory drugs. Due to excessive usage of naproxen, this drug has been determined even in drinking water. In this study, four fungal strains Phanerochaete chrysosporium, Funalia trogii, Aspergillus niger, and Yarrowia lipolytica were investigated in terms of naproxen removal abilities. According to LC/MS data, A...
November 10, 2016: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
https://www.readbyqxmd.com/read/27758707/new-psychoactive-substances-3-methoxyphencyclidine-3-meo-pcp-and-3-methoxyrolicyclidine-3-meo-pcpy-metabolic-fate-elucidated-with-rat-urine-and-human-liver-preparations-and-their-detectability-in-urine-by-gc-ms-lc-high-resolution-msn-and-lc-high-resolution
#8
Julian A Michely, Sascha K Manier, Achim T Caspar, Simon D Brandt, Jason Wallach, Hans H Maurer
3-Methoxyphencyclidine (3-MeO-PCP) and 3-methoxyrolicyclidine (3-MeO-PCPy) are two new psychoactive substances (NPS). The aims of the present study were the elucidation of their metabolic fate in rat and pooled human liver microsomes (pHLM), the identification of the cytochrome P450 (CYP) isoenzymes involved, and the detectability using standard urine screening approaches (SUSA) after intake of common users' doses using gas chromatography-mass spectrometry (GC-MS), liquid chromatography-multi-stage mass spectrometry (LC-MSn), and liquid chromatography-high-resolution tandem mass spectrometry (LC-HR-MS/MS)...
October 18, 2016: Current Neuropharmacology
https://www.readbyqxmd.com/read/27738170/methane-production-from-coal-by-a-single-methanogen
#9
Daisuke Mayumi, Hanako Mochimaru, Hideyuki Tamaki, Kyosuke Yamamoto, Hideyoshi Yoshioka, Yuichiro Suzuki, Yoichi Kamagata, Susumu Sakata
Coal-bed methane is one of the largest unconventional natural gas resources. Although microbial activity may greatly contribute to coal-bed methane formation, it is unclear whether the complex aromatic organic compounds present in coal can be used for methanogenesis. We show that deep subsurface-derived Methermicoccus methanogens can produce methane from more than 30 types of methoxylated aromatic compounds (MACs) as well as from coals containing MACs. In contrast to known methanogenesis pathways involving one- and two-carbon compounds, this "methoxydotrophic" mode of methanogenesis couples O-demethylation, CO2 reduction, and possibly acetyl-coenzyme A metabolism...
October 14, 2016: Science
https://www.readbyqxmd.com/read/27692933/characterization-of-oxycodone-in-vitro-metabolism-by-human-cytochromes-p450-and-udp-glucuronosyltransferases
#10
Stéphanie Romand, Dany Spaggiari, Niloufar Marsousi, Caroline Samer, Jules Desmeules, Youssef Daali, Serge Rudaz
The hepatic metabolism of oxycodone by cytochromes P450 (CYP) and the UDP-glucuronosyltransferases (UGT), the main metabolic enzymes of phase I and phase II, respectively, was assessed in vitro. The N-demethylation by CYP3A4/5 and the O-demethylation by CYP2D6 in human liver microsomes (HLM) followed Michaelis-Menten kinetics, with intrinsic clearances of 1.46μL/min/mg and 0.35μL/min/mg, respectively. Although noroxycodone and oxymorphone mainly contribute to the elimination of oxycodone, the simulated total in vivo clearance using in vitro phase I metabolism was underestimated...
September 26, 2016: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27686399/pharmacokinetic-properties-in-vitro-metabolism-and-plasma-protein-binding-of-govaniadine-an-alkaloid-isolated-from-corydalis-govaniana-wall
#11
Lucas M M Marques, Daniel R Callejon, Larissa G Pinto, Michel L de Campos, Anderson R M de Oliveira, Ricardo Vessecchi, Achyut Adhikari, Ram L S Shrestha, Rosangela G Peccinini, Norberto P Lopes
Govaniadine (GOV) is an alkaloid isolated from Corydalis govaniana Wall. It has been reported to show a different number of biological activities including anti-urease, leishmanicidal and antinociceptive. The present study aims to characterize the GOV in vitro metabolism after incubation with rat and human liver microsomes (RLM and HLM, respectively) and to evaluate its pharmacokinetic properties. The identification of GOV metabolites was conducted by different mass analyzers: a micrOTOF II-ESI-ToF Bruker Daltonics(®) and an amaZon-SL ion trap (IT) Bruker Daltonics(®)...
November 30, 2016: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27646602/ancistectorine-d-a-naphthylisoquinoline-alkaloid-with-antiprotozoal-and-antileukemic-activities-and-further-5-8-and-7-1-linked-metabolites-from-the-chinese-liana-ancistrocladus-tectorius
#12
Gerhard Bringmann, Raina Seupel, Doris Feineis, Guoliang Zhang, Minjuan Xu, Jun Wu, Marcel Kaiser, Reto Brun, Ean-Jeong Seo, Thomas Efferth
From the twigs and stems of the Chinese liana Ancistrocladus tectorius (Ancistrocladaceae), two new 5,8'-coupled naphthylisoquinolines, ancistectorine D (5) and its 6-O-demethyl derivative 6, were isolated, along with two new 7,1'-linked alkaloids, 6-O-methylancistectorine B1 (7) and ancistectorine B2 (8). Two further compounds, ancistroealaine A (4) and 6-O-demethyl-8-O-methyl-7-epi-ancistrobrevine D (10), already known from related Asian and African Ancistrocladus species, were discovered for the first time in A...
December 2016: Fitoterapia
https://www.readbyqxmd.com/read/27619234/metabolism-of-melatonin-in-the-skin-why-is-it-important
#13
Andrzej T Slominski, Igor Semak, Tobias W Fischer, Tae-Kang Kim, Konrad Kleszczyński, Ruediger Hardeland, Russel J Reiter
Melatonin is produced in almost all living taxa and is probaly 2-3 billion years old. Its pleiotropic activities are related to its local concentration that is secondary to its local synthesis, delivery from distant sites and metabolic or non-enzymatic consumption. This consumption generates metabolites through indolic, kynuric and cytochrome P450 (CYP) mediated hydroxylations and O-demethylation or non-enzymatic processes, with potentially diverse phenotypic effects. While melatonin acts through receptor dependent and independent mechanism, receptors for melatonin metabolites remain to be identified, while their receptor independent activities are well documented...
September 13, 2016: Experimental Dermatology
https://www.readbyqxmd.com/read/27616336/intramolecular-oxidative-o-demethylation-of-an-oxoferryl-porphyrin-complexed-with-a-per-o-methylated-%C3%AE-cyclodextrin-dimer
#14
Hiroaki Kitagishi, Shun Kurosawa, Koji Kano
The intramolecular oxidation of ROCH3 to ROCH2 OH, where the latter compound spontaneously decomposed to ROH and HCHO, was observed during the reaction of the supramolecular complex (met-hemoCD3) with cumene hydroperoxide in aqueous solution. Met-hemoCD3 is composed of meso-tetrakis(4-sulfonatophenyl)porphinatoiron(III) (Fe(III) TPPS) and a per-O-methylated β-cyclodextrin dimer having an -OCH2 PyCH2 O- linker (Py=pyridine-3,5-diyl). The O=Fe(IV) TPPS complex was formed by the reaction of met-hemoCD3 with cumene hydroperoxide, and isolated by gel-filtration chromatography...
September 12, 2016: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/27597253/concurrent-estimation-of-metabolite-concentrations-along-with-parent-drug-quantification-in-post-mortem-blood
#15
Jenni Viinamäki, Ilkka Ojanperä
There is a constant demand for the quantification of drug metabolites within post-mortem toxicology. Especially electrospray ionization-mass spectrometry techniques necessitate that calibration is carried out using primary reference standards due to the non-uniform ionization efficiency between parent drugs and their metabolites. As reference standards for metabolites are not readily available and their costs are high, alternative methods for immediate quantification are required. In this study, ultra-high performance liquid chromatography coupled with photodiode array detection and corona charged aerosol detection was utilized for the concurrent quantification of 23 drug metabolites using the corresponding parent drug for calibration...
October 2016: Forensic Science International
https://www.readbyqxmd.com/read/27580591/pharmacokinetics-of-dextromethorphan-and-its-metabolites-in-horses-following-a-single-oral-administration
#16
Carley R Corado, Daniel S McKemie, Heather K Knych
Dextromethorphan is an N-methyl-D-aspartate (NMDA) non-competitive antagonist commonly used in human medicine as an antitussive. Dextromethorphan is metabolized in humans by cytochrome P450 2D6 into dextrorphan, which is reported to be more potent than the parent compound. The goal of this study is to describe the metabolism of and determine the pharmacokinetics of dextromethorphan and its major metabolites following oral administration to horses. A total of 23 horses received a single oral dose of 2 mg/kg...
September 1, 2016: Drug Testing and Analysis
https://www.readbyqxmd.com/read/27514509/cyp3a11-mediated-testosterone-6%C3%AE-hydroxylation-decreased-while-ugt1a9-mediated-propofol-o-glucuronidation-increased-in-mice-with-diabetes-mellitus
#17
Rong Shi, Jiasheng Wu, Cong Meng, Bingliang Ma, Tianming Wang, Yuanyuan Li, Yueming Ma
The db/db mouse is one of the most popular animal models for type 2 diabetes mellitus, but changes in the activities of important P450s and UGTs are still not completely clear. This study was designed to investigate the alterations of major hepatic cytochrome P450s and UDP-glucuronyltransferase enzymes in db/db mice. Mouse liver microsomes (MLMs) were obtained from male db/db mice and their wild type littermates. After incubation of the substrates separately with MLMs, the samples were pooled and analysed by high-throughput liquid chromatography-tandem mass spectrometry system for the simultaneous study of nine phase I metabolic reactions and three glucuronidation conjugation reactions to determine the activity of the metabolic enzymes...
October 2016: Biopharmaceutics & Drug Disposition
https://www.readbyqxmd.com/read/27496443/tacrolimus-metabolite-m-iii-may-have-nephrotoxic-and-myelotoxic-effects-and-increase-the-incidence-of-infections-in-kidney-transplant-recipients
#18
J Zegarska, E Hryniewiecka, D Zochowska, E Samborowska, R Jazwiec, A Borowiec, W Tszyrsznic, A Chmura, S Nazarewski, M Dadlez, L Paczek
BACKGROUND: Tacrolimus (Tac) is one of the most commonly used immunosuppressive drugs after solid organ transplantation. Eight Tac metabolites have been described, but their clinical importance remains unclear. The aim of this study was quantification of the 2 major Tac metabolites, 13-O-demethyl (M-I) and 15-O-demethyl (M-III), in kidney transplant recipients and to link them with parameters of kidney and liver function, peripheral blood cell counts, and infection incidence. METHODS: In 81 kidney transplant recipients, concentrations of Tac, M-I, and M-III were measured with the use of liquid chromatography combined with tandem mass spectrometry (LC-MS-MS)...
June 2016: Transplantation Proceedings
https://www.readbyqxmd.com/read/27448631/25c-nbome-and-25i-nbome-metabolite-studies-in-human-hepatocytes-in-vivo-mouse-and-human-urine-with-high-resolution-mass-spectrometry
#19
Ariane Wohlfarth, Markus Roman, Mikael Andersson, Fredrik C Kugelberg, Xingxing Diao, Jeremy Carlier, Caroline Eriksson, Xiongyu Wu, Peter Konradsson, Martin Josefsson, Marilyn A Huestis, Robert Kronstrand
25C-NBOMe and 25I-NBOMe are potent hallucinogenic drugs that recently emerged as new psychoactive substances. To date, a few metabolism studies were conducted for 25I-NBOMe, whereas 25C-NBOMe metabolism data are scarce. Therefore, we investigated the metabolic profile of these compounds in human hepatocytes, an in vivo mouse model and authentic human urine samples from forensic cases. Cryopreserved human hepatocytes were incubated for 3 h with 10 μM 25C-NBOMe and 25I-NBOMe; samples were analyzed by liquid chromatography high-resolution mass spectrometry (LC-HRMS) on an Accucore C18 column with a Thermo QExactive; data analysis was performed with Compound Discoverer software (Thermo Scientific)...
July 23, 2016: Drug Testing and Analysis
https://www.readbyqxmd.com/read/27400739/characterization-of-the-hepatic-cytochrome-p450-enzymes-involved-in-the-metabolism-of-25i-nbome-and-25i-nboh
#20
Line Marie Nielsen, Niels Bjerre Holm, Sebastian Leth-Petersen, Jesper Langgaard Kristensen, Lars Olsen, Kristian Linnet
The dimethoxyphenyl-N-((2-methoxyphenyl)methyl)ethanamine (NBOMe) compounds are potent serotonin 5-HT2A receptor agonists and have recently been subject to recreational use due to their hallucinogenic effects. Use of NBOMe compounds has been known since 2011, and several non-fatal and fatal intoxication cases have been reported in the scientific literature. The aim of this study was to determine the importance of the different cytochrome P450 enzymes (CYP) involved in the metabolism of 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2methoxybenzyl)ethanamine (25I-NBOMe) and 2-[[2-(4-iodo-2,5dimethoxyphenyl)ethylamino]methyl]phenol (25I-NBOH) and to characterize the metabolites...
July 12, 2016: Drug Testing and Analysis
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