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Derivatives of 5-alkylpyrazine-2-carboxylic acid as potential anti-infectives
Halířová, Martina ; Zitko, Jan (advisor) ; Kučerová, Marta (referee)
DERIVATIVES OF 5-ALKYLPYRAZINE-2-CARBOXYLIC ACID AS POTENTIAL ANTI-INFECTIVES HALÍŘOVÁ MARTINA Department of Pharmaceutical Chemistry and Drug Analysis, Faculty of Pharmacy in Hradec Králové, Charles University, Czech Republic In our previous study, we have demonstrated that 5-alkylamino-N- phenylpyrazine-2-carboxamides with longer alkyl chain (C5-C8) exerted micromolar growth inhibition activity against M. tuberculosis H37Rv. We speculated that the long alkylamino chain could facilitate the penetration of lipophilic mycobacterial cell envelope. To test this hypothesis, we performed the amino to methylene isosteric exchange and designed a series of 5-alkyl-N-phenylpyrazine-2-carboxamides. 5- Alkylpyrazine-2-carboxylic acids (5-Ak-POA) were prepared by homolytic alkylation of commercially available pyrazine-2-carbonitrile by respective alkanoic acid, followed by hydrolysis of the carbonitrile group. Final derivatives were prepared by CDI mediated coupling of 5-Ak-POA with corresponding aniline at RT. Final compounds were described by melting point, elementary analysis, IR spectroscopy and 1 H, 13 C NMR. Then they were tested in vitro for antimycobacterial activity against M. tuberculosis H37Rv and several non-tuberculous mycobacterial strains. Several compounds exerted MIC of 3.13-6.25 µg mL-1 ....
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Synthesis of BODIPY derivatives for photodynamic therapy
Rydrych, Milan ; Zimčík, Petr (advisor) ; Zitko, Jan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Author: Milan Rydrych Supervisor: Prof. PharmDr. Petr Zimčík, PhD. Name of the thesis: Synthesis of BODIPY dyes for photodynamic therapy Borron-dipyromethene dyes (BODIPYs) have been used since the 1990s for their photostability, high absorption coefficients and fluorescence quantum yields. Recently, a modification of the structure using the heavy atom effect was discovered, where high quantum yields of singlet oxygen were also achieved. This fact helped creating a family of compounds with the potential for use in photodynamic therapy (PDT). Previously described BODIPY preparations for PDT are limited by poor solubility in polar environments. This study provides an overview of current synthetic options and basic structure-effect relationships. In the experimental part of the work, three styryl disubstituted substances were prepared with λmax (absorption maximum) at wavelengths in near infrared region with good quantum yields of singlet oxygen and very good photostability. In addition to the target compounds, three 3,5- dialkoxy substituted benzaldehyde derivatives were prepared and characterized as precursors for the final compounds. Finally, the already published synthetic...
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Synthesis and biological evaluation of novel tacrine-tryptophan derivatives
Astapenko, Michaela ; Opletalová, Veronika (advisor) ; Zitko, Jan (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Kralove Department of Pharmaceutical Chemistry and Drug Control Student: Michaela Jarošová Supervisor: Assoc. Prof. RNDr. Veronika Opletalová, Ph.D. Consultant: PharmDr. Jan Korábečný, Ph.D. Title of thesis: Study and biological evaluation of new tacrine-tryptophan derivatives Alzheimer's disease (AD) is a chronic neurodegenerative disease with characteristic histopathological changes in the brain. It is the most common cause of dementia. There is about 7.4 million people affected by AD in Europe today. In connection with aging of the population a significant increase of patients affected by the disease can be expected in the coming years. The cause of neural tissue damage is aggregated amyloid β (Aβ), which disrupts neurons by creating glial hem with consequent inflammatory processes. Hyperphosphorylated τ-protein causes neuronal damage intracellularly by forming so-called neurofibrillary tangles. This leads to macroscopically visible brain atrophy and loss of neurons. Current AD pharmacotherapy is based on influencing the cholinergic system. Acetylcholinesterase inhibitors (AChEIs) - rivastigmine, donepezil and galanthamine are used for this purpose. Memantine, antagonist of N-methyl-D-aspartate receptors (NMDA) has been approved for the...
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Synthesis of aerothionin analogs as potential antimycobacterial agents
Šimovičová, Martina ; Zitko, Jan (advisor) ; Zimčík, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Author: Martina Šimovičová Supervisors: Assoc. Prof. PharmDr. Jan Zitko, Ph.D.; Adjunct Prof. Paula Kiuru, Ph.D. Title of diploma thesis: Synthesis of aerothionin analogs as potential antimycobacterial agents Key words: antimycobacterial; tuberculosis; synthesis; aerothionin; bromotyrosines Drugs currently used for the treatment of tuberculosis are the result of studies carried out 50 or 60 years ago. With the constantly growing bacterial resistance to these pharmaceuticals grows also the importance of research for new antimycobacterially active compounds. The marine environment undoubtedly holds an enormous potential for discovering new leads for the development of antitubercular agents. One of these leads is a spirocyclic compound called aerothionin (1), which was found to be active against multidrug-resistant strains of Mycobacterium tuberculosis, as well as three non-tuberculosis mycobacteria (Figure 1). In addition, several spirocyclic structures (not only from marine origin) were discovered to affect on the M. tuberculosis in recent years, making this structure segment attractive for antitubercular research. Figure 1: Aerothionin (1) and general structure of the...
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Derivatives combining the fragment of pyrazinamide and 4-aminosalicylic acid as antimycobacterial compounds
Šlechta, Petr ; Zitko, Jan (advisor) ; Zimčík, Petr (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical chemistry and Pharmaceutical analysis Author: Petr Šlechta Supervisor: doc. PharmDr. Jan Zitko, Ph.D. Consultant: MSc. Ghada Basem Bouz, Ph.D. Title of diploma thesis: Derivatives combining the fragment of pyrazinamide and 4-aminosalicylic acid as antimycobacterial compounds According to WHO, tuberculosis (TB) is the leading cause of death from a single infectious organism worldwide and the number of cases with drug resistant TB is still increasing, creating the need for new antituberculotics. Therefore, we report design, synthesis and antimicrobial evaluation of a series of hybrid compounds combining different pyrazinamide derivates and p- aminosalicylic acid as potential antituberculotic agents. The compounds were prepared by mixing different pyrazinecarboxylic acids, after activation by 1,1'-carbonyldiimidazole, with p- aminosalicylic acid in dimethylsulfoxide as a solvent. Obtained compounds were in vitro tested for their antimycobacterial activity against M. tuberculosis H37Rv, M. tuberculosis H37Ra and four other mycobacterial strains. Prepared compounds were also in vitro screened for antibacterial, antifungal, and cytotoxic (HepG2) activity. Most compounds showed antimycobacterial activity in range of...
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Modulation of pKa of the recognition moiety of azaphthalocyanine sensors
Čermáková, Veronika ; Zimčík, Petr (advisor) ; Zitko, Jan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Veronika Čermáková Supervisor: Assoc. Prof. Petr Zimčík, Ph.D. Title of Diploma Thesis: Modulation of pKa of the recognition moiety of azaphtalocyanine sensors Azaphthalocyanines (AzaPc) are macrocyclic compounds containing a large system of conjugated double bonds that enables them to absorb light in the red part of the spectrum that is promising in biological applications. They are characterized by intense red fluorescence as one of the relaxation pathways of the excited state after absorbing a photon. The fluorescence of AzaPc substituted with a phenol moieties on the periphery can be switched ON/OFF depending on the pH of the environment and the pKa of the phenolic group. In basic medium, the molecule occurs as phenolate and undergoes intramolecular charge transfer between the phenolate group (a donor) and the electron- deficient macrocyclic core (an acceptor). As a consequence of this process, the fluorescence is quenched. Switching between ON/OFF states in phenol-substituted AzaPc is dependent on the proton concentration and thus can be utilized in pH sensing. The aim of this work was to synthesize derivatives of phenol-substituted AzaPcs whose pKa is...
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Creation and analysis of in-house database of pyrazine derivatives with potential antimicrobial activity
Kebakuile, Legae Gomolemo Boemo ; Zitko, Jan (advisor) ; Kučerová, Marta (referee)
In the early phases of drug design and development, scientists must overcome many challenges involved in identifying potential drug-like or lead-like compounds. This has led to the need of creating large sets of chemical data which will aid in improving the identification of pharmacophores and active compounds. Various scientific fields especially pharmacology, medicinal chemistry and biochemistry have begun to employ the use of computer sciences to aid in the screening for potential leads with more specificity with regards to drug-like compounds' or substances' bioactivity. The emphasis of this project was to create a database containing a collection of pyrazine compounds synthesized overtime in the Faculty of Pharmacy (Charles University, Hradec Kralove) with the aim of having anti-mycobacterium (and possible antibacterial and antifungal) activity, and further utilize this database to predict certain pharmacokinetic and bioavailability properties. This project seeks to demonstrate how certain molecular descriptors can be used as reliable chemoinformation to determine the likeliness or possibility of developing a lead-like or drug-like compound by utilizing computer software. An in-house database of 623 compounds saved in SMILES format was created and used in demonstrating quantitative...
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Synthesis of BODIPY derivatives for photodynamic therapy
Rydrych, Milan ; Zimčík, Petr (advisor) ; Zitko, Jan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Author: Milan Rydrych Supervisor: Prof. PharmDr. Petr Zimčík, PhD. Name of the thesis: Synthesis of BODIPY dyes for photodynamic therapy Borron-dipyromethene dyes (BODIPYs) have been used since the 1990s for their photostability, high absorption coefficients and fluorescence quantum yields. Recently, a modification of the structure using the heavy atom effect was discovered, where high quantum yields of singlet oxygen were also achieved. This fact helped creating a family of compounds with the potential for use in photodynamic therapy (PDT). Previously described BODIPY preparations for PDT are limited by poor solubility in polar environments. This study provides an overview of current synthetic options and basic structure-effect relationships. In the experimental part of the work, three styryl disubstituted substances were prepared with λmax (absorption maximum) at wavelengths in near infrared region with good quantum yields of singlet oxygen and very good photostability. In addition to the target compounds, three 3,5- dialkoxy substituted benzaldehyde derivatives were prepared and characterized as precursors for the final compounds. Finally, the already published synthetic...
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Amidoxime derivatives as synthetic intermediates and potential drugs
Hariková, Michaela ; Kučerová, Marta (advisor) ; Zitko, Jan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Title of diploma thesis: Amidoxime derivatives as synthetic intermediates and potential drugs Student: Michaela Hariková Supervisor: PharmDr. Marta Kučerová, Ph.D. In the theoretical part of this diploma thesis, biological effects of N-hydroxykarbimidoylchlorides and amino derivatives are summarized. In addition, biologically active compounds which are synthesized from N-hydroxykarbimidoylchlorides, in particular the compounds containing isoxazole. In the experimental part, the procedures used for the synthesis of amidoxime derivatives are described. Initial compounds for the synthesis of N-hydroxykarbimidoylchlorides were the corresponding alkylated amidoximes available at the Department of Pharmaceutical Chemistry and Pharmaceutical Analysis or prepared by radical alkylation of pyrazinecarbonitrile followed by conversion to amidoxime. From the N-hydroxykarbimidoylchloride, an amino derivative was subsequently prepared. All prepared compounds were characterized by melting point, NMR and IR spectra. The purity of the substances was checked by TLC and elemental analysis. The prepared derivatives were tested in vitro for their antibacterial, antimycobacterial and antifungal activity.
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Creation of a virtual library of synthetic compounds for practical use in a molecular modelling study
Vávrová, Jitka ; Kučerová, Marta (advisor) ; Zitko, Jan (referee)
Charles University, Pharmaceutical Faculty in Hradec Králové Department: Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Jitka Vávrová Supervisor: PharmDr. Marta Kučerová, Ph.D. Title of Diploma Thesis: Creation of a virtual library of synthetic compounds for practical use in a molecular modelling study Drug development is a process requiring the analysis of a large amount of data.Creating a virtual library of synthesized compounds provides access to primary data concerning structure, results of biological activity studies, and molecular descriptors necessary for drug- like prediction. Chemical databases are usually used in virtual screening, which is a modern strategy of Computer Assisted Drug Design (CADD). Molecular docking is one of the methods. Microsoft Excel was used to create the database, which includes different structural types, e.g., pyrazine, rhodanine, thiazolidin-2,4-dione, and 1,2,4-oxadiazole derivatives prepared in the research group Design and Development of New Antimicrobial Agents. Molecules are available in a spreadsheet containing all compounds in a line-notation ready-to- dock format. To demonstrate this database's actual usage, a molecular modelling study was performed using the software Molecular Operating Environment (MOE). This study...
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