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Flexible nanofiber separator based on a zinc metal-organic framework
Pisarenko, Tatiana ; Holečková, Jana
In this paper, a flexible composite of polyvinylidene fluoride (PVDF) and zinc-based metal-organic frameworks (MOF) was successfully designed and synthesized. This material can serve as a separator or active filter to trap gases or heavy metals in wastewater such as uranium. The fabricated sample is in the form of a nanofiber mat with doped MOFs created by electrospinning. The results show successful incorporation of MOF nanoparticles in the fibers. Measurement was performed using scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. Novel PVDF@Zn-MOF nanofibers is a promising material that can have a great impact in the field of water treatment and solve environmental questions in developing countries.
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Nonsymmetrically substituted macrocyclic ligands
Rusnáková, Michaela ; Hermann, Petr (advisor) ; Kamlar, Martin (referee)
Complexes of metal ions with derivatives of 1,4,7,10-tetraazacyclododecane (cyclen) are used in various applications, such as contrast agents for magnetic resonance imaging (MRI). The structure of ligands affects the thermodynamic, kinetic, and relaxation properties of the complexes. The unsymmetrically substituted monoamide DO3AP is particularly interesting from this perspective. Synthesis of non-symmetrically substituted cyclen derivatives requires the use of orthogonal protection of cyclen. With intention to synthesize monoamide DO3AP, this thesis presents the preparation of a monoprotected cyclen, two types of orthogonal protection of cyclen, and a substitution of the protected cyclen with acetate pendant arms. Key words: Complexes, ligands, macrocycles, protection groups, synthesis
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Synthesis of selaginpulvilin X.
Havlíková, Tereza ; Rýček, Lukáš (advisor) ; Nečas, David (referee)
4 Abstract This bachelor work aims to synthesize the natural product selaginpulvilin X using a six-step synthetic route. Subsequently, the spectra of the synthesized compound were compared with the spectra of the previously isolated compound from the genus Selaginella to verify the proposed structure of selaginpulvilin X. The total synthesis of natural product deploys Suzuki and Sonogashira coupling, generation, and addition of an organolithium compound to aldehyde, consecutive oxidation, and final deprotection. Various protective groups are also used in the preparation of selaginpulvilin X derivatives. Keywords: Natural product, total synthesis, genus Selaginella, Selaginellaceae polyphenols, selaginpulvilin X, Suzuki-Miyaura coupling, Sonogashira coupling
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Synthesis and characterization of UZM-9 zeolite
Koreň, Branislav ; Kubů, Martin (advisor) ; Bulánek, Roman (referee)
UZM-9 zeolite of LTA framework holds significant importance due to its unique structure and properties, making it suitable for various industrial processes such as gas separation, ion exchange, and catalysis. Optimizing the synthesis process is crucial to enhance its performance and applicability. This research aims to contribute to develop efficient and cost- effective methods for its production, furthering its potential in industrial applications. The main objectives include the optimization of synthesis parameters, isomorphous substitution, and adsorption studies. Optimization involved the addition of seeding crystals, reducing structure-directing agents, and selecting reactant sources. Direct synthesis of Fe and Zr forms of the UZM-9 zeolite by isomorphous substitution was studied. Adsorption studies examined CO2 on different cation forms, while the texture properties were studied by nitrogen adsorption. Prepared zeolites were further characterised by XRPD, SEM, ICP-MS, and FT-IR. Results show significantly improved crystallization times, enhanced texture properties, and the effects of using various sources of reactants. Isomorphous substitution of Fe atoms was unsuccessful, while showing promising results for Zr. Various ion-exchanged forms of UZM-9 zeolite were shown to have their adsorption...
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Preparation of enantiomerically enriched triazolium salts suitable for catalysis
Čermák, Daniel ; Veselý, Jan (advisor) ; Navrátil, Rafael (referee)
The subject of this work is the preparation of multiple chiral triazole-derived conjugate acids of N-heterocyclic carbenes (NHC), a class of covalent organocatalysts used in many stereoselective transformations. The NHC conjugate acids in question were prepared in the form of triazolium salts by multi-step syntheses starting from readily available natural compounds. The prepared chiral triazolium salts were used as pre-catalysts in a chosen enantioselective spiroannulation reaction between a benzofuranone derivative and an α-bromoenal compound. Additionally, an alternative oxidative approach to the key azolium- dienolate intermediate was explored.
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Synthesis and evaluation of potential antitubercular agents based on nitro aromates
Delong, Jakub ; Krátký, Martin (advisor) ; Kučerová, Marta (referee)
The goal of the master's thesis was the synthesis and assessment of potential molecules against tuberculosis based on aromatic compounds containing nitro groups. The thesis reviews tuberculosis and its therapy, in the theoretical part, followed by well-know and new nitro group containing antibiotics. The experimental part reports multitep synthesis from parent compounds - substituted benzoic acid, pyruvic acid and variously substituted anilines, which were evaluated for their antimycobacterial activity. The core structure of the prepared compound molecules is N-phenyl-2-[2-(3,5- dinitrobenzoyl)hydrazinylidene]propanamide, which was variously substituted on the benzene ring of N-phenylpropanamide. In case of four compounds, one nitro group was switched to the trifluoromethyl group. Yields varied from 7 to 72 % and their minimum inhibitory concentrations (MIC) ranged from 4 to more than 1000 µmol/l. N-(4-Bromphenyl)-2-[2-(3,5- dinitrobenzoyl)hydrazinylidene]propanamide proved to be the most effective derivate. Key words Antibiotics, antimycobacterial activity, 3,5-dinitrobenzohydrazide, nitro group, synthesis, tuberculosis
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Synthesis and investigation of potential antimicrobial compounds
Pokorná, Anežka ; Krátký, Martin (advisor) ; Zitko, Jan (referee)
One of the ways to alleviate the global problem of antibiotic resistance is, among other things, the synthesis and development of new antimicrobials. All compounds prepared in this work are based on the molecule 4-amino-1-benzylpiperidine or its isomer 4-(piperidin-1- ylmethyl)aniline. The parent molecule was chosen on the based on its previously reported activity. Thirteen imines were prepared using one-step synthesis by reacting the starting amine with the corresponding aldehyde. Two additional syntheses led to the amides by reaction of the starting molecule with the corresponding salicylic acid. The yields of the reactions ranged from 26 to 97 % for the imines and were 25 and 39 % for the amides. All compounds were prepared in sufficient quantity and purity to determine biological activity. All fifteen compounds were tested for their antibacterial activity against clinically relevant Gram-positive and Gram-negative strains. They were further tested for their antifungal activity, antimycobacterial aktivity, and their ability to inhibit the enzymes acetylcholinesterase and butyrylcholinesterase was also tested. The results of the evaluation showed that the amides were ineffective against microbes, but some imines showed excellent results. In general, the compounds were more active against...
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Synthesis and evaluation of potential antimicrobial agents based on steroidal scaffold
Požárová, Pavla ; Krátký, Martin (advisor) ; Matouš, Petr (referee)
Antibiotic resistance represents a significant threat to humanity. To combat this trend, the development of new effective substances can be employed to potentially reverse its progression. Due to the broad range of biological activities exhibited by steroid structures, estrone was chosen as the starting material and was modified through various reactions. In total, fifteen new compounds were synthesized, which were tested for their antibacterial, antifungal, and antimycobacterial activities, and additionally for cholinesterases inhibition. The modification of estrone primarily involved two different approaches, resulting in the formation of hydrazones and esters. Twelve compounds were prepared through these steps. For the remaining three derivatives, changes in the starting materials or procedures were necessary. In the case of four compounds, it was necessary to synthesize one of the reactants. The yields ranged from 62% to 95% for hydrazones and from 8% to 54% for esters. The antibacterial activity was tested against four selected Gram-positive and Gram-negative strains. Antifungal activity was evaluated against four yeasts and filamentous fungi. Antimycobacterial activity was tested against five mycobacterial strains. All these methods utilized the microdilution broth method. The tested...
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Synthesis and coordination behaviour of diphenylphosphinoferrocifen
Křelinová, Magda ; Schulz, Jiří (advisor) ; Kubíček, Vojtěch (referee)
Title: Synthesis and coordination behaviour of diphenylphosphinoferrocifen Author: Bc. Magda Křelinová Department: Department of Inorganic Chemistry Supervisor: RNDr. Jiří Schulz, Ph.D. Abstract: Ferrocifen, as a ferrocene analog of a commonly used drug - tamoxifen, showed promising activity against breast cancer cells - both the hormone-dependent type and the hormone-independent one. The treatment of the latter is a struggle for today's medicine and a new effective treatment is urgently needed. One of the goals of this thesis was to optimize the synthesis of 1-{1-[bis(4-hydroxyphenyl)methylene]propyl}-1'-(diphenylphosphino) ferrocene (compound 4), which will provide a way of conjugating the ferrocifenol moiety to metal complexes, that are also studied as anticancer agents. The combination of those effects could provide some interesting results against cancer cells. In this thesis, 8 complexes of compound 4 as a ligand were prepared. All of these compounds were subsequently tested on cancerous (MDA-MB-231, and A549) as well as non-cancerous (MCF10A) cell lines to assess their biological activity and potential selectivity towards cancerous cells. Ru Cl Cl P Ph2 Fe HO OH 6 Ru Cl Cl P Ph2 Fe HO OH 7 Ru Cl Cl P Ph2 Fe HO OH 8 Ru Cl Cl P Ph2 Fe HO OH 9 Ir Cl Cl P Ph2 Fe HO OH 10 Rh Cl Cl P Ph2 Fe HO OH 11 Fe P...
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Synthesis and evaluation of potential drugs for neurodegenerative diseases
Foltýnová, Eva ; Krátký, Martin (advisor) ; Vinšová, Jarmila (referee)
The topic of this thesis is the synthesis of oxadiazole derivatives and their precursors as potential therapeutics for neurodegenerative diseases, and their evaluation primarily as potential inhibitors of cholinesterases (CHE). The theoretical part of this thesis focuses on Alzheimer's disease, particularly its pathophysiology, diagnosis, and treatment. It also discusses CHE inhibitors that are already clinically used, as well as new structures with potential for future clinical use. Additionally, it addresses the oxadiazole fragment, its chemical and biological properties. In the experimental work, derivatives of 1,3,4- and 1,2,4-oxadiazoles were synthesized, which differed not only in the type of oxadiazole but also in their substitution. These substances were prepared by the cyclization of precursors, which were also prepared and tested. For 1,3,4- oxadiazoles, besides their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), their potential antimycobacterial, antibacterial, and antifungal activities were tested. For 1,2,4-oxadiazoles, so far, only their inhibitory activity against AChE and BuChE has been tested. A total of twenty-two substances were synthesized, and the yields of these syntheses ranged from 21-97%. The compound with the lowest IC50 value...
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