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Synthesis of analogues of chelator SIH with increased stability towards hydrolysis
Kruchkou, Pavel ; Karabanovich, Galina (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Supervisor: Ing. Galina Karabanovich, Ph.D. Student: Pavel Kruchkou Title of Thesis: Synthesis of analogues of chelator SIH with increased stability towards hydrolysis Excessive amounts of free iron ions in the body can catalyze the formation of hydroxyl radicals, which are involved in the development of various diseases. One of the ways how to protect the body is to chelate free iron ions with chelators, in order to prevent the development of iron- catalyzed oxidative stress. Effective chelators are substances from the group of salicylaldehyde analogues of isonicotinoyl hydrazone. Salicylaldehyde isonicotinoyl hydrazone (SIH) is a chelator that forms complexes with Fe 3+ ions. Due to its high lipophilicity can be administered orally. Its main disadvantage is the low stability in the aqueous environment caused by the rapid hydrolysis of the hydrazone bond. The aim of this work was to synthesize a series of new aroylhydrazones derived from the SIH chelator, which supposed to have an improved ability to chelate iron ions and the associated ability to protect cells from oxidative stress and potentially increased stability to hydrolysis. In the first series of SIH analogs - N...
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The study of model lipid membranes containing omega-hydroxylated ceramides
Svatošová, Linda ; Opálka, Lukáš (advisor) ; Pullmannová, Petra (referee)
Charles University, Faculty of pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Linda Svatošová Supervisor: PharmDr. Lukáš Opálka, Ph.D. Title of diploma thesis: The study of model lipid membranes containing omega- hydroxylated ceramides Acylceramides (EO-Cer) belong to a class of ceramides (Cer) with an ultralong acyl chain whose ω-hydroxyl group is esterified with linoleic acid. The importance of EO-Cer lies in the formation of the long periodicity phase (LPP) and the corneocyte lipid envelope (CLE), which are indispensable components for the skin functioning as a barrier. Disorders in EO-Cer biosynthesis are associated with insufficient production of CLE and LPP leading to many skin diseases, including some types of ichthyosis. One of the enzymes that is deficient in such ichthyoses is PNPLA1. Insufficient function of this enzyme disables ω-esterification with linoleic acid, and thus the formation of EO-Cer. On the contrary, their precursors, i.e. ω-hydroxylated ceramides (O-Cer), are cumulated. The aim of this thesis was to prepare model membranes containing O-Cer and to study the effects of O-Cer on the lipid organization and barrier properties of model membranes. Within this thesis, two types of membranes were prepared - the first type were membranes...
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Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome
Sedláková, Jana ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic And Bioorganic Chemistry Candidate: Jana Sedláková Supervisors: Dr. Fabrizio Pertusati doc. PharmDr. Jaroslav Roh, Ph.D. Title of diploma thesis: Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome At the present time, no effective treatment is available neither for the most of the congenital disorders of glycosylation (CDGs) nor the mitochondrial DNA depletion syndrome (MDS). Regarding the CDG therapy, D-mannose-1-phosphate (Man-1-P) offers considerable pharmacological potential to improve the pathological patterns in patients affected by phosphomannomutase 2 deficiency (PMM2-CDG), similarly as N-acetyl-D-mannosamine-6-phosphate (ManNAc-6-P) in case of GNE myopathy (GNEM). Administration of selected deoxyribonucleotides was proposed as a potential pharmacological strategy for the treatment of MDS. Unfortunately, the problematic membrane penetration of such polar molecules reduces their effect and limits their clinical application. Hydrophobic, membrane permeable derivatives of the sugar monophosphates and nucleotides, might represent more efficient potential therapeutics for CDGs and...
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Synthesis and evaluation of human 6-hydroxyceramides
Majcher, Adam ; Opálka, Lukáš (advisor) ; Krátký, Martin (referee)
Title of the Master thesis: Synthesis and evaluation of human 6-hydroxyceramides Candidate: Adam Majcher Supervisor: PharmDr. Lukáš Opálka, Ph.D. Consultant: PharmDr. Andrej Kováčik, Ph.D. Charles University, Faculty of Pharmacy in Hradec Králové Skin Barrier Research Group, Department of Organic and Bioorganic Chemistry Ceramides (Cer), the members of sphingolipid family, occur in all human cells and play an important role in cell signaling. In high concentrations, Cer can also be found in the uppermost layer of epidermis called stratum corneum, along with free fatty acids and cholesterol (in equimolar ratio), where they form the intercellular multi-lamellar lipid matrix. The key function of stratum corneum is to ensure a permeability barrier, thus, to provide water and electrolyte homeostasis, and to prevent entry of harmful substances into the organism. Cer are composed of a sphingoid base and an acyl part derived from a long-chain fatty acid. Cer based on 6-hydroxysphingosine (H) are amongst the most unusual sphingolipids. In contrast to sphingosine-based Cer, 6-hydroxysphingosine-based Cer (H-Cer) are unique for the epidermis and, in addition, H-Cer are not typical for all mammals. Moreover, the function and biosynthesis of H-Cer in the skin is still not completely understood. Several...
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Nucleophile-Assisted Gold(I)-Catalyzed Cyclizations of Enynes
Kadaník, Michal ; Pour, Milan (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Michal Kadaník Supervisor: Prof. RNDr. Milan Pour, Ph.D. Title of thesis: Nucleophile-Assisted Gold(I)-Catalyzed Cyclizations of Enynes This work is focused on gold(I)-catalyzed cyclizations of substituted enyne in the presence of a nucleophile. The screening of various gold catalysts, silver co-catalysts, solvents and nucleophiles was performed. We achieved the formation of substituted tetrahydropyridine with excellent diastereoselectivity by optimization of the reaction conditions. To extend our methology, the second part deals with the gold(I)-catalyzed cyclization of the enyne with chiral center. The cyclization was found to be enantioselective. Keywords: gold catalysis, tetrahydropyridines, hemiaminals, hemiaminalethers
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Synthesis of new types of succinimides as a potential adjuvant
Božiková, Slavomíra ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Student: Slavomíra Božiková Supervisor: doc. PharmDr. Jaroslav Roh, Ph.D. Consultant: RNDr. Dávid Maliňák, PhD Title of Diploma Thesis: Synthesis of new types of succinimides as a potential adjuvant Adjuvants represent a big group of the compounds used for the increased immune response to vaccines. This whole concept of these helper substances is more than 80 years old. The first finding that started the research of more substances was the alternative system of the aluminium salt. Important group of adjuvants are substances, which activate the immunity system to increased reaction after stimulation of toll-like receptors (TLRs) that are present in the human body. These receptors are considered as one of the most important immunity molecules. The best examined receptors of this group is the TLR4 receptor that binds various ligands. The most important ligands are the lipopolysaccharide of Gram-negative bacteria. Mechanisms of the interaction of these ligands with TLR4 are being examined recently. In my thesis I focused on the TLR4 receptors and on the synthesis of new molecules of the succinimide type, which eventually can stimulate these receptors and be potential adjuvants.
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Use of lactones in acylceramide synthesis
Moravčík, Štefan ; Opálka, Lukáš (advisor) ; Roh, Jaroslav (referee)
6 Abstract Acylceramides, subgroup of ceramides with ultralong chains, are essential component of extracellular lipid matrix in the uppermost skin layer, stratum corneum. They have crucial role in mammalian survival on dry land. Deeper understanding of their function in physiology of pathophysiology of the skin and their therapeutic potential are hampered by their limited availability. Analysis of the skin surface lipids of the ass (E. asinus) has shown, that these lipids contain up to 56% of unbranched ω-lactones (equolides), from which 51.2% is mono- unsaturated dotriacontanolide and 41.3% is mono-unsaturated triacontanolide. Carbon chain length of these lactones match the most common length of carbon chain in acylceramides (30 and 32 carbon atoms) therefore they could be used in their total synthesis. Aim of this thesis was to isolate mono-unsaturated ω-lactone with 32 carbon chain (dotriacontanolide) from the mixture of donkey skin surface lipids, followed by hydrogenation and transformation to the suitable precursor (succinmidyl ester) in order to find the easiest synthetic path in its conversion to acylceramides. We have tried many synthetic pathways. From direct aminolysis of lactone, through reaction with N-hydroxysuccinimide in various reaction conditions to opening of the lactone to the potassium...
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Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome
Sedláková, Jana ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic And Bioorganic Chemistry Candidate: Jana Sedláková Supervisors: Dr. Fabrizio Pertusati doc. PharmDr. Jaroslav Roh, Ph.D. Title of diploma thesis: Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome At the present time, no effective treatment is available neither for the most of the congenital disorders of glycosylation (CDGs) nor the mitochondrial DNA depletion syndrome (MDS). Regarding the CDG therapy, D-mannose-1-phosphate (Man-1-P) offers considerable pharmacological potential to improve the pathological patterns in patients affected by phosphomannomutase 2 deficiency (PMM2-CDG), similarly as N-acetyl-D-mannosamine-6-phosphate (ManNAc-6-P) in case of GNE myopathy (GNEM). Administration of selected deoxyribonucleotides was proposed as a potential pharmacological strategy for the treatment of MDS. Unfortunately, the problematic membrane penetration of such polar molecules reduces their effect and limits their clinical application. Hydrophobic, membrane permeable derivatives of the sugar monophosphates and nucleotides, might represent more efficient potential therapeutics for CDGs and...
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Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome
Sedláková, Jana ; Roh, Jaroslav (advisor) ; Opálka, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Organic And Bioorganic Chemistry Candidate: Jana Sedláková Supervisors: Dr. Fabrizio Pertusati doc. PharmDr. Jaroslav Roh, Ph.D. Title of diploma thesis: Synthesis of phosphoramidate prodrugs "ProTides" as novel potential therapeutic agents for the treatment of congenital disorders of glycosylation and mitochondrial DNA depletion syndrome At the present time, no effective treatment is available neither for the most of the congenital disorders of glycosylation (CDGs) nor the mitochondrial DNA depletion syndrome (MDS). Regarding the CDG therapy, D-mannose-1-phosphate (Man-1-P) offers considerable pharmacological potential to improve the pathological patterns in patients affected by phosphomannomutase 2 deficiency (PMM2-CDG), similarly as N-acetyl-D-mannosamine-6-phosphate (ManNAc-6-P) in case of GNE myopathy (GNEM). Administration of selected deoxyribonucleotides was proposed as a potential pharmacological strategy for the treatment of MDS. Unfortunately, the problematic membrane penetration of such polar molecules reduces their effect and limits their clinical application. Hydrophobic, membrane permeable derivatives of the sugar monophosphates and nucleotides, might represent more efficient potential therapeutics for CDGs and...
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Optimization of the synthesis of 32-hydroxydotriacontanoic acid
Sommerová, Veronika ; Opálka, Lukáš (advisor) ; Roh, Jaroslav (referee)
1 Abstract Acylceramides belong to the subgroup of ultralong chain ceramides. They are essential components of the extracellular lipid matrix of stratum corneum, where they play a crucial role in proper function of skin barrier (they help preventing the excessive water loss and penetration of exogenous substances and pathogens to the organism). The 32-hydroxydotriacontanoic acid is one of the fatty acids forming the backbone of all the acylceramides. In the molecule of acylceramide, the carboxyl group of this acid is bound to a primary amino group of the sphingoid base and the ω-hydroxy group is esterified with linoleic acid. In the stratum corneum, 32-hydroxydotriacontanoic acid may remain as a part of free acylceramides or it can be covalently linked to the surface of corneocytes and form the "first lamela", which then serves as a basis for the orientation of other lipids in the matrix. The recent literature describes the synthesis of 32-hydroxydotriacontanoic acid but only with relatively small overall yields. The most problematic part of the synthesis seems to be the connection of two shorter fragments leading to the ultralong chain. The main aim of this research project was to optimalise the reaction conditions to increase the yield of formation of the utralong acid, focusing on the most complicated...
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