Effective resolution of racemic pirlindole at the preparative scaleDe Tullio, Pascal ; ; Liégeois, Jean-François et alin Chirality (1999), 11 Detailed reference viewed: 18 (5 ULg) Enantiomeric Separation of Pirlindole by Liquid Chromatography Using Different Types of Chiral Stationary PhasesCeccato, Attilio ; Hubert, Philippe ; De Tullio, Pascal et alin Journal of Pharmaceutical & Biomedical Analysis (1998), 18(4-5), 605-14 The enantioseparation of pirlindole by liquid chromatography (LC) was investigated using three different chiral stationary phases (CSPs) containing either cellulose tris-(3,5-dimethylphenylcarbamate ... [more ▼] The enantioseparation of pirlindole by liquid chromatography (LC) was investigated using three different chiral stationary phases (CSPs) containing either cellulose tris-(3,5-dimethylphenylcarbamate) (Chiralcel OD-R), ovomucoid (OVM) or beta-cyclodextrin (beta-CD). The effects of the mobile phase pH on retention, enantioselectivity and resolution were studied. Methanol and acetonitrile were tested as organic modifiers while the influence of the addition to the mobile phase of sodium alkanesulfonates or sodium perchlorate was also investigated. Sodium perchlorate was only used on the Chiralcel OD-R column while sodium alkanesulfonates were tested as mobile phase additives on the three kinds of CSPs. The enantioseparation of pirlindole could be obtained on all CSPs tested, the best results with respect to chiral resolution being achieved on the Chiralcel OD-R and the OVM columns. The use of sodium octanesulfonate (NaOS) was found to improve the enantioseparation of pirlindole on the OVM column while enantioselectivity was considerably enhanced by addition of sodium perchlorate on the Chiralcel OD-R column. [less ▲] Detailed reference viewed: 39 (4 ULg) Simultaneous Determination of Pirlindole Enantiomers and Dehydropirlindole by Chiral Liquid ChromatographyCeccato, Attilio ; Hubert, Philippe ; De Tullio, Pascal et alin Journal of Pharmaceutical & Biomedical Analysis (1998), 17(6-7), 1071-9 Liquid chromatography was employed for the determination of pirlindole enantiomers and its oxidation product dehydropirlindole (DHP). The direct separation of pirlindole enantiomers and DHP was achieved ... [more ▼] Liquid chromatography was employed for the determination of pirlindole enantiomers and its oxidation product dehydropirlindole (DHP). The direct separation of pirlindole enantiomers and DHP was achieved on a cellulose tris-(3,5-dimethylphenylcarbamate) chiral stationary phase (Chiralcel OD-R). Acetonitrile was used as the organic modifier and sodium perchlorate was used as an ionic additive in the mobile phase. The influence of acetonitrile and sodium perchlorate concentrations on enantioselectivity and achiral selectivity towards DHP was investigated in order to find suitable conditions for the determination of low amounts of each analyte. The mobile phase selected consisted of a mixture of acetonitrile and phosphate buffer (pH 5.0) containing sodium perchlorate (0.05 M) (35:65, v/v) and the UV detector was set at 220 nm. The method developed was validated and was found to be linear in the 0.1-5 microg ml(-1) range (r2 = 0.999 for the three compounds). Repeatability and the intermediate precision for the three analytes at a concentration of 0.1 microg ml(-1) were about 3 and 4%, respectively. This concentration corresponds to the quantification of 0.1% for the minor enantiomer. Actual determinations of enantiomeric purity for single enantiomers of pirlindole were performed. [less ▲] Detailed reference viewed: 11 (2 ULg) Effective resolution of racemic pirlindole at the preparative scale: derivatization method and absolute configurationDe Tullio, Pascal ; Ceccato, Attilio ; Liégeois, Jean-François et alPoster (1998, September) Detailed reference viewed: 18 (1 ULg) Preparative resolution of racemic pirlindole: chromatographic methods and determination of the absolute configurationDe Tullio, Pascal ; Ceccato, Attilio ; Liégeois, Jean-François et alPoster (1998, September) Detailed reference viewed: 5 (0 ULg) Séparation énantiomérique du pirlindole à l’échelle préparativeDe Tullio, Pascal ; ; Felekidis, Apostolos et alPoster (1998, January 16) Detailed reference viewed: 4 (0 ULg) Comparative study of pirlindole, a selective RIMA, and its two enantiomers using biochemical and behavioural techniques.; Liégeois, Jean-François ; et alin Behavioural Pharmacology (1998), 9(8), 731-7 The interaction with monoamine oxidase A (MAO-A) and B has been shown to be sensitive to the absolute configuration of molecules. Therefore, the aim of this study was to compare the effects of the racemic ... [more ▼] The interaction with monoamine oxidase A (MAO-A) and B has been shown to be sensitive to the absolute configuration of molecules. Therefore, the aim of this study was to compare the effects of the racemic pirlindole (a selective and reversible MAO-A inhibitor) and its two enantiomers using biochemical techniques (in vitro and ex vivo determination of rat brain MAO-A and MAO-B activity) and behavioural models (forced swimming test and reserpine-induced hypothermia and palpebral ptosis test). In vitro, the MAO-A IC50 of (+/-)-pirlindole, R-(-)-pirlindole and S-(+)-pirlindole were 0.24, 0.43 and 0.18 microM, respectively. Ex vivo, their ID50 were 24.4, 37.8 and 18.7 mg/kg i.p. The differences between the three compounds were not significant, with a ratio between the two enantiomers [R-(-)/S-(+)] of 2.2 in vitro and 2.0 ex vivo. MAO-B was only slightly inhibited. In the forced swimming test and the reserpine-induced hypothermia and ptosis model, the three compounds had an antidepressant profile. In the forced swimming test, the minimal effective dose ratio between the R-(-) and the S-(+) was again around 2.0. The behavioural observations were thus clearly in accordance with the biochemical data. [less ▲] Detailed reference viewed: 22 (2 ULg) Facilitatory effects of chronically administered citicoline on learning and memory processes in the dog.; Liégeois, Jean-François ; in Progress in Neuro-Psychopharmacology & Biological Psychiatry (1998), 22(1), 115-28 1. Citicoline (cytidine (5') diphosphocholine) has been shown to reverse aging-induced memory deficits, scopolamine-induced amnesia and nucleus basalis magnocellularis lesion-induced learning impairment ... [more ▼] 1. Citicoline (cytidine (5') diphosphocholine) has been shown to reverse aging-induced memory deficits, scopolamine-induced amnesia and nucleus basalis magnocellularis lesion-induced learning impairment. 2. This study aimed to evaluate the effects of citicoline on learning and retrieval processes in a complex differential reinforcement of response duration schedule in normal dogs. 3. The effects of citicoline on a stabilized performance were also measured in order to be able to differentiate specific memory effects from non specific influences on the motor, neuro-vegetative and motivational systems. 4. The results demonstrate that citicoline can exert facilitatory effects on learning and memory but also on retrieval processes. The complete absence of effects on the stabilized performance and on the motor, neuro-vegetative and motivational systems constitutes arguments in favour of a selectivity of action on the memory processes. [less ▲] Detailed reference viewed: 23 (1 ULg) Horseradish peroxidase electrode for phenothiazine analysis; ; et al in Electroanalysis (1998), 10 Detailed reference viewed: 16 (10 ULg) Dopamine D4 receptors, a new opportunity for research on schizophreniaLiégeois, Jean-François ; ; et alin Current Medicinal Chemistry (1998), 5 Detailed reference viewed: 9 (1 ULg) Liquid chromatographic separation of pirlindole enantiomers using different types of chiral stationary phasesCeccato, Attilio ; Hubert, Philippe ; De Tullio, Pascal et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 7 (0 ULg) Tentatives de synthèse énantiosélective des isomères R et S du pirlindolPirotte, Bernard ; De Tullio, Pascal ; et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 12 (1 ULg) Determination of the enantiomeric purity of pirlindole by liquid chromatography using a cellulose based chiral stationary phaseCeccato, Attilio ; Hubert, Philippe ; De Tullio, Pascal et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 6 (0 ULg) Résolution préparative du pirlindol, journées franco-belges de pharmacochimieDe Tullio, Pascal ; ; Liégeois, Jean-François et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 10 (0 ULg) Tentatives de synthèse énantiosélective des isomères R et S du pirlindolePirotte, Bernard ; De Tullio, Pascal ; et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 15 (2 ULg) First preparative enantiomer resolution of pirlindole, a potent antidepressant drugDe Tullio, Pascal ; Felekidis, Apostolos ; Pirotte, Bernard et alin Helvetica Chimica Acta (1998), 81 Detailed reference viewed: 15 (1 ULg) Preparative resolution of racemic pirlindole: chromatographic methods and determination of the absolute configurationDe Tullio, Pascal ; ; Liégeois, Jean-François et alin European Journal of Pharmaceutical Sciences (1998), suppl.1 Detailed reference viewed: 14 (3 ULg) Résolution préparative du pirlindoleDe Tullio, Pascal ; Felekidis, Apostolos ; Liégeois, Jean-François et alin Journal de Pharmacie de Belgique (1998), 53 Detailed reference viewed: 11 (3 ULg) Jl 13, a Potential Successor to Clozapine, Is Less Sensitive to Oxidative PhenomenaLiégeois, Jean-François ; Mouithys-Mickalad, Ange ; et alin Biochemical and Biophysical Research Communications (1997), 238(1), 252-5 The oxidation behaviour of JL 13, a promising antipsychotic, was investigated in comparison with clozapine and loxapine, by measuring their direct "radical scavenging" abilities and their efficacies in ... [more ▼] The oxidation behaviour of JL 13, a promising antipsychotic, was investigated in comparison with clozapine and loxapine, by measuring their direct "radical scavenging" abilities and their efficacies in inhibiting the lipid peroxidation. In the lipid peroxidation system, the reactivity of these compounds with free radicals produced by gamma-irradiation of linoleic acid may be presented as follows: JL 13 = loxapine < clozapine. In two enzymatic systems (HRP/GSH and HRP/H2O2/ GSH) which generate the thiyl free radicals, clozapine produces a strong enhancement of the thiyl-radical EPR signal intensity while JL 13 and loxapine exhibit no or minimal effect on this signal. The redox potential values for the three derivatives confirm the spectro-photometric and EPR results. Following this study, we show that JL 13, although presenting a preclinical clozapine-like profile, appears less sensitive to oxidation than clozapine. [less ▲] Detailed reference viewed: 12 (5 ULg) Simultaneous determination of pirlindole enantiomers and dehydropirlindole by liquid chromatography using a cellulose based chiral stationary phase; Hubert, Philippe ; De Tullio, Pascal et alPoster (1997, September) Detailed reference viewed: 4 (0 ULg) |
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