National Repository of Grey Literature 7 records found  Search took 0.00 seconds. 
Voltammetric determination of 1-hydroxy-N-(4-nitrophenyl)naphthalene-2-carboxamide by voltammetry at a glassy carbon electrode in microvolumes of dimethyl sulfoxide
Gajdar, J. ; Goněc, T. ; Jampílek, J. ; Brázdová, Marie ; Bábková, Zuzana ; Fojta, Miroslav ; Barek, J. ; Fischer, J.
Voltammetric reduction and oxidation of 1-hydroxy-N-(4-nitrophenyl) naphthalene-2-carboxamide was investigated at glassy carbon electrode in dimethyl sulfoxide. Cyclic voltammetry was used to investigate the mechanism of reduction of nitro group and oxidation of hydroxyl group. The analyte was successfully determined in dimethyl sulfoxide by differential pulse voltammetry and the whole voltammetric procedure was miniaturised. Square wave voltammetry was employed to reduce the interference from dissolved oxygen. Determination in one drop (20 mu L) of 0.1 mol L-1 tetrabutyl-ammonium tetrafluoroborate in dimethyl sulfoxide provided very similar results compared to determination in the bulk solution. Limits of quantification were 5.0 mu mol L-1 for cathodic voltammetry and 5.3 mu mol L-1 for anodic voltammetry.
Voltammetry of 1-Hydroxy-N-(4-nitrophenyl)naphthalene-2-carboxamide at a Glassy Carbon Electrode
Gajdar, J. ; Goněc, T. ; Jampílek, J. ; Brázdová, Marie ; Bábková, Zuzana ; Fojta, Miroslav ; Barek, J. ; Fischer, J.
This electrochemical study is aimed at an investigation of a reaction mechanism and determination of 1-hydroxy-N-(4-nitrophenyl)naphthalene-2-carboxamide in media with various amount of an organic solvent (dimethyl sulfoxide or methanol). The studied analyte is a model substance from a group of recently prepared drugs with antibiotic characteriss Mechanism of reducible nitro group and oxidisable hydroxyl group is compared with studies of substructures and structurally similar compounds. Preliminary comparison of different media was carried out to find the best parameters for the determination.
Voltammetric Techniques for Analysis in a Single Drop of a Solution
Gajdar, J. ; Goněc, T. ; Jampílek, J. ; Brázdová, Marie ; Bábková, Zuzana ; Fojta, Miroslav ; Barek, J. ; Fischer, J.
This contribution describes miniaturization of voltammetric methods and some of the main problems caused by reducing the sample volume to 20 mu L. This study was carried out in dimethyl sulfoxide solutions and buffered aqueous solutions with 10% DMSO at a glassy carbon electrode. A novel antibiotic agent, 1-hydroxy-N-(4-nitrophenyl) naphthalene-2-carboxamide, was used as a model substance. This analyte was determined by cathodic and anodic voltammetry. Elimination of the negative influence of dissolved oxygen was performed in various manners. Two most effective methods were square wave voltammetry that can be used in the presence of dissolved oxygen and removal of oxygen in a microcell with nitrogen atmosphere inside.
Determination of a Novel Antimycobacterial Agent in a Single Drop of a Solution by Voltammetry at a Glassy Carbon Electrode
Gajdar, J. ; Goněc, T. ; Jampílek, J. ; Brázdová, Marie ; Bábková, Zuzana ; Fojta, Miroslav ; Barek, J. ; Fischer, J.
One of the novel antimycobacterial agents from the group of hydroxynaphthalene carboxamides (namely I-hydroxy-X-(4-nitrophenyl)naphthalene-2-carboxamide) was investigated using voltammetric methods for the first time. The study was carried out at a glassy carbon electrode by methods of cathodic and anodic differential pulse voltammetry in micro volumns (20 mu L) of an aqueous solution at pH 7 containing 10% dimethyl sulfoxide and in a real matrix of a bacterial growth medium. The miniaturized method was compared with the macro volume determination. The presence of oxygen in micro volumes presents the biggest obstacle for the miniaturized method.
Relationship between Structure and Biological Activity of new Modulators of Acetylcholinesterase
Komlóová, Markéta ; Doležal, Martin (advisor) ; Kuneš, Jiří (referee) ; Jampílek, Josef (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department: Dpt. of Pharmaceutical Chemistry and Drug Control Student: Mgr. Markéta Komlóová Supervisor: prof. PharmDr. Martin Doležal, Ph.D. Title of Doctoral Thesis: Relationship between structure and biological activity of new modulators of acetylcholinesterase This work focuses on the preparation of peripherally acting AChE inhibitors as a potential treatment of myasthenia gravis. These compounds could also be used as a pre- treatment of poisoning by organophosphorus AChE inhibitors. They can occupy the active site of an enzyme making it inaccessible for irreversible inhibitors. Compounds used in this indication should fulfill these requirements: inhibit efficiently AChE (standards currently used in the treatment were chosen for the comparison of the inhibitory efficacy), have selective effect on AChE and not to cross the blood-brain barrier in order to lower the possible side effects. Six series of bisquaternary compounds were prepared. Their inhibitory ability was determined in vitro against human erythrocyte or recombinant AChE and human plasmatic BChE. According to inhibitory ability values acquired, a structure - activity relationships were investigated in every series. A few compounds with significant affinity towards...
Examination of Potential Ligands of the Constitutive Androstane Receptor CAR
Zadák, Vojtěch ; Pávek, Petr (advisor) ; Jampílek, Josef (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Mgr. Vojtěch Zadák Supervisor: Doc. PharmDr. Petr Pávek, Ph.D. Title of rigorous thesis: Examination of potential ligands of the constitutive androstane receptor CAR Year of completion: 2010 The constitutive androstane receptor - CAR is a representative of nuclear receptors that form a super-family of ligand-activated transcription factors regulating expression of target genes. In the last decade, CAR was mainly investigated in connection with an induction of biotransformation enzymes by remedies or other xenobiotics but in the past few years the research has also concentrated on a role of this receptor in hormone, lipid and energy homeostasis. Recently, there have been revealed some new important metabolic functions of CAR that may establish this "xenobiotic receptor" as a new therapeutic target for treatment of type 2 diabetes, obesity and dyslipidemia. The aim of this experimental rigorous thesis has been the examination of potential ligands of the human CAR (hCAR) from a given group of 16 chemicals with a defined structure. Using methods gene reporter assay, two-hybrid assay and one-hybrid assay we have tested this group from the perspective of an interaction with hCAR. The...
Screening of acyclovir permeation through skin using alaptide
Bobálová, Janette ; Černíková, A. ; Bobáľ, P. ; Jampílek, J.
This investigation deals with the affection of the permeation of acyclovir through fullthickness\npig ear skin using a Franz diffusion cell from the donor vehicle of propylene\nglycol/water (1:1) using synthesised (S)-8-methyl-6,9-diazaspiro[4.5]decane-7,10-\ndione, alaptide as a potential transdermal permeation enhancer.