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Jeanmichel Gaulier - One of the best experts on this subject based on the ideXlab platform.
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unusual pattern in hair after Prazepam exposure
Toxicologie Analytique et Clinique, 2014Co-Authors: Julie Maublanc, S Dulaurent, Laurent Imbert, Pascal Kintz, Jeanmichel GaulierAbstract:Summary Prazepam is known to be totally and quickly metabolized in nordiazepam, oxazepam, and 3-hydroxyPrazepam after oral intake, and consequently to be undetectable in blood or in urine. The authors reported a case of positive findings of Prazepam in hair. After a drug-facilitated sexual assault (DFSA), a large screening for benzodiazepines, hypnotics and other psychotropic drugs was performed in the victim's hair sample, collected one month after the aggression. The positive analytical findings were firstly, zolpidem presence in the hair segment corresponding to the DFSA period (zolpidem was afterwards identified as the used weapon for the DFSA), and secondly, Prazepam (together with nordiazepam) presence in all the analysed hair segments. This last result was in connection with the regular Prazepam treatment of the victim (LYSANXIA, at a dose of 3 × 10 mg tablets per day). The presence in hair of a parent compound, which is not usually detected in blood or in urine is not incongruous, as attested by the presence of heroin in addicts’ hair. However, the possibility of Prazepam presence in hair raises questions about the analytical methods that do not look for this benzodiazepine in hair, and worse still about those using Prazepam as aninternal standard. Indeed, in case of the presence of Prazepam in hair, theses analytical methods will not only be incapable of detecting Prazepam, but, they will also underestimate the concentrations of other benzodiazepines sought at the same time.
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mise en evidence de Prazepam dans du sang post mortem apres intoxication par le paracetamol le dextropropoxyphene et le Prazepam
Annales De Toxicologie Analytique, 2013Co-Authors: Francois Mathiaux, Bernard Magret, G Lachatre, Jeanmichel GaulierAbstract:Objectif : Le Prazepam est largement et rapidement metabolise apres ingestion. Sa detection dans le sang est de ce fait exceptionnelle. Nous rapportons le cas d’une polyintoxication par le Prazepam, le dextropropoxyphene et le paracetamol pour laquelle une concentration significative de Prazepam a ete relevee dans le sang post-mortem . Methode : Une expertise toxicologique a ete realisee par differentes techniques, incluant la chromatographie liquide avec detections par spectrophotometrie et spectrometrie de masse en tandem, et la chromatographie gazeuse avec spectrometrie de masse. Resultats : Il a ete detecte dans le sang les xenobiotiques suivants : dextropropoxyphene a une concentration de 6420 μ g/L, paracetamol a une concentration de 342 μ g/L, Prazepam a une concentration de 178 μ g/L, nordazepam et oxazepam aux concentrations respectives de 2517 μ g/L et 113 μ g/L. Conclusion : Deux hypotheses sont proposees pour expliquer la presence de Prazepam : une interaction medicamenteuse et/ou une necrose hepatique induite par l’intoxication au paracetamol.
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article original original article mise en evidence de Prazepam dans du sang post mortem apres intoxication par le paracetamol le dextropropoxyphene et le Prazepam Prazepam detection in post mortem blood after acetaminophen dextropropoxyphene and praz
2013Co-Authors: Francois Mathiaux, Bernard Magret, G Lachatre, Jeanmichel GaulierAbstract:Resume – Objectif : Le Prazepam est largement et rapidement metabolise apres ingestion. Sa detection dans le sang est de ce fait exceptionnelle. Nous rapportons le cas d’une polyintoxication par le Prazepam, le dextropropoxyphene et le paracetamol pour laquelle une concentration significative de Prazepam a ete relevee dans le sang post-mortem. Methode : Une expertise toxicologique a ete realisee par differentes techniques, incluant la chromatographie liquide avec detections par spectrophotometrie et spectrometrie de masse en tandem, et la chromatographie gazeuse avec spectrometrie de masse.Resultats : Il a ete detecte dans le sang les xenobiotiques suivants : dextropropoxyphene a une concentration de 6420 µg/L, paracetamol a une concentration de 342 µg/L, Prazepam a une concentration de 178 µg/L, nordazepam et oxazepam aux concentrations respectives de 2517 µg/L et 113 µg/L. Conclusion : Deux hypotheses sont proposees pour expliquer la presence de Prazepam : une interaction medicamenteuse et/ou une necrose hepatique induite par l’intoxication au paracetamol. Mots cles : Prazepam, dextropropoxyphene, paracetamol
A Ismail E M Mohamed - One of the best experts on this subject based on the ideXlab platform.
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acid base equilibria of diazepam and Prazepam in montmorillonite suspensions
Talanta, 1998Co-Authors: A Ismail E M MohamedAbstract:Abstract The distribution of ionic species of diazepam and Prazepam in aqueous and aqueous montmorillonite clay suspensions at several pH conditions (pH 1–12) was monitored spectrophotometrically. Measurements were performed at 284 and 365 nm for diazepam and 285 and 361 nm for Prazepam. The interaction between the negative clay surface and protonated species of the drugs studied relative to the unchanged species is responsible for the apparent displacement of p K a values from 3.3 and 2.7 to 4.4 and 3.9 for diazepam and Prazepam respectively. Changes in the partial molar free energy of the ionic species of both drugs (Δ G i ) as a result of interactions with montmorillonite suspensions was −1.47 and −1.72 for diazepam and Prazepam respectively. The effect of an additional ionic solute i.e. sodium chloride was also studied. The recovered amounts of both drugs from five different concentrations of veegum at pH 2, 5 and 10 indicates the effect of drug–clay interactions in drug analysis.
P E Fournier - One of the best experts on this subject based on the ideXlab platform.
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comparison of performance of healthy volunteers given Prazepam alone or combined with ethanol relation to drug plasma concentrations
International Clinical Psychopharmacology, 1991Co-Authors: Catherine Girre, M Hirschhorn, L Bertaux, S Palombo, P E FournierAbstract:The interaction between a single dose of 20 mg of Prazepam and (1.5 g/kg body weight ethanol was investigated in 12 healthy male volunteers by nine objective performance tests, eight visual analogue self-rating scales and measurement of Prazepam and ethanol plasma concentrations, using a double-blin
Francesco Demartin - One of the best experts on this subject based on the ideXlab platform.
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cyclometallated derivatives of palladium ii with 1 4 benzodiazepin 2 ones crystal structure of l h pd pph3 cl chcl3 l Prazepam 7 chloro 1 cyclopropylmethyl 1 3 dihydro 5 phenyl 2h 1 4 benzodiazepin 2 one synthesis of isoindolo 2 1 d 1 4 benzodiazepin
Journal of Organometallic Chemistry, 1991Co-Authors: Maria Agostina Cinellu, Giovanni Minghetti, Serafino Gladiali, Sergio Stoccoro, Francesco DemartinAbstract:Abstract The dimeric cyclometallated derivatives of palladium(II) [( L -H)PdCl] 2 , 3 ( L = 1 , Diazepam: 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2 H -1,4-benzodiazepin-2-one) and 4 ( L = 2 , Prazepam: 7-chloro-1-cyclopropylmethyl-1,3-dihydro-5-phenyl-2 H -1,4-benzodiazepin-2-one) react with triphenylphosphine to give the complexes ( L -H)Pd(PPh 3 )Cl, 5 ( L = Diazepam) and 6 ( L = Prazepam). The crystal structure of 6 was determined by X-ray crystallography. The palladium atom is in a square planar arrangement. The deprotonated ligand is bound to the metal through the 4-nitrogen and the ortho -carbon atom of the 5-phenyl substituent. The phosphorous and the chlorine atoms are trans to the nitrogen and the carbon atoms, respectively: PdN = 2.085(2), PdP=2.263(1), PdCl = 2.377(1), PdC = 2.009(3) A. The reaction of the dimeric derivatives [( L -H)PdCl] 2 with carbon monoxide was investigated. Under mild conditions (1 atm of CO, room temperature) the unstable ( L -H)Pd(CO)Cl derivatives. 7 ( L = Diazepam) and 8 ( L = Prazepam) are formed, but at high pressure and temperature (60–100 atm of CO, 45–50°C), extrusion of palladium occurs and tetracyclic derivatives having an isoindolo ring condensed on the 1,4-benzodiazepin-2-one system, 9–12 , are obtained.
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Cyclometallated derivatives of palladium(II) with 1,4-benzodiazepin-2-ones. Crystal structure of (L-H)Pd(PPh3)Cl·CHCl3 (L = Prazepam: 7-chloro-1-cyclopropylmethyl-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one). Synthesis of isoindolo[2,1-d][1,4]ben
Journal of Organometallic Chemistry, 1991Co-Authors: Maria Agostina Cinellu, Giovanni Minghetti, Serafino Gladiali, Sergio Stoccoro, Francesco DemartinAbstract:Abstract The dimeric cyclometallated derivatives of palladium(II) [( L -H)PdCl] 2 , 3 ( L = 1 , Diazepam: 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2 H -1,4-benzodiazepin-2-one) and 4 ( L = 2 , Prazepam: 7-chloro-1-cyclopropylmethyl-1,3-dihydro-5-phenyl-2 H -1,4-benzodiazepin-2-one) react with triphenylphosphine to give the complexes ( L -H)Pd(PPh 3 )Cl, 5 ( L = Diazepam) and 6 ( L = Prazepam). The crystal structure of 6 was determined by X-ray crystallography. The palladium atom is in a square planar arrangement. The deprotonated ligand is bound to the metal through the 4-nitrogen and the ortho -carbon atom of the 5-phenyl substituent. The phosphorous and the chlorine atoms are trans to the nitrogen and the carbon atoms, respectively: PdN = 2.085(2), PdP=2.263(1), PdCl = 2.377(1), PdC = 2.009(3) A. The reaction of the dimeric derivatives [( L -H)PdCl] 2 with carbon monoxide was investigated. Under mild conditions (1 atm of CO, room temperature) the unstable ( L -H)Pd(CO)Cl derivatives. 7 ( L = Diazepam) and 8 ( L = Prazepam) are formed, but at high pressure and temperature (60–100 atm of CO, 45–50°C), extrusion of palladium occurs and tetracyclic derivatives having an isoindolo ring condensed on the 1,4-benzodiazepin-2-one system, 9–12 , are obtained.
Claudio Villani - One of the best experts on this subject based on the ideXlab platform.
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dynamic high performance liquid chromatography on chiral stationary phases low temperature separation of the interconverting enantiomers of diazepam flunitrazepam Prazepam and tetrazepam
Journal of Chromatography A, 2014Co-Authors: Rocchina Sabia, Alessia Ciogli, Marco Pierini, Francesco Gasparrini, Claudio VillaniAbstract:Abstract Diazepam and the structurally related 1,4-benzodiazepin-2-ones tetrazepam, Prazepam and flunitrazepam are chiral molecules because they adopt a ground state conformation featuring a non-planar seven membered ring devoid of any reflection-symmetry element. The two conformational enantiomers of this class of benzodiazepines interconvert rapidly at room temperature by a simple ring flipping process. Low temperature HPLC on the Whelk-O1 chiral stationary phase allowed us to separate the conformational enantiomers of diazepam and of the related 1,4-benzodiazepin-2-ones, under conditions where the interconversion rate is sufficiently low, compared to the chromatographic separation rate. Diazepam, tetrazepam and Prazepam showed temperature dependent dynamic HPLC profiles with interconversion plateaus indicative of on-column enantiomer interconversion (enantiomerization) in the temperature range between −10 °C and −35 °C, whereas for flunitrazepam on-column interconversion was observed at temperatures between −40 °C and −66 °C. Simulation of exchange-deformed HPLC profiles using a computer program based on the stochastic model yielded the apparent rate constants for the on-column enantiomerization and the corresponding free energy activation barriers. At −20 °C the enantiomerization barriers, Δ G ≠ , for diazepam, Prazepam and tetrazepam were determined to be in the range 17.6–18.7 kcal/mol. At −55 °C Δ G ≠ for flunitrazepam was determined to be in the 15.6–15.7 kcal/mol range. The experimental dynamic chromatograms and the corresponding interconversion barriers reported in this paper call for a reinterpretation of previously published results on the HPLC behavior of diazepam on chiral stationary phases.
