11 results on '"Branislav, Horváth"'
Search Results
2. A systematic study of <scp> tert ‐ </scp> butylacrylamide‐methyl acrylate‐acrylic acid radical solution terpolymerization
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Maryam Agboluaje, Gagandeep Kaur, Eva Dušička, Anna Urbanová, Mohammad Pishnamazi, Branislav Horváth, Miroslav Janata, Vladimír Raus, Igor Lacík, and Robin A. Hutchinson
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General Chemical Engineering - Published
- 2023
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Catalog
3. Synthesis, Surface Activity, and Biological Activities of Phosphonium and Metronidazole Salts
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Martin Mrva, Aneta Dušeková, Martin Pisárčik, Andrej Vrták, Mária Garajová, Branislav Horváth, Ferdinand Devínsky, Miloš Lukáč, and Renáta Horáková
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biology ,General Chemical Engineering ,biology.organism_classification ,Surfaces, Coatings and Films ,Acanthamoeba ,chemistry.chemical_compound ,Metronidazole ,chemistry ,Critical micelle concentration ,medicine ,Phosphonium ,Physical and Theoretical Chemistry ,medicine.drug ,Nuclear chemistry - Published
- 2020
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4. Toxicity of primulic acid 1 against a daphnid species Simocephalus expinosus s.l
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Branislav Horváth, Martin Pisárčik, Renáta Horáková, M. Bajcura, Ferdinand Devínsky, and Miloš Lukáč
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critical micelle concentration ,010405 organic chemistry ,Chemistry ,daphnid ,primula root ,RM1-950 ,010402 general chemistry ,01 natural sciences ,ecotoxicology ,0104 chemical sciences ,Biochemistry ,Toxicity ,extraction ,Therapeutics. Pharmacology ,General Pharmacology, Toxicology and Pharmaceutics ,Primulic acid - Abstract
Primulic acid 1 is the main saponin present in Primula elatior. The present study describes the isolation of this amphiphilic compound from primula root. It was performed by ultrasonic maceration, reverse-phase column chromatography and crystallization. Investigations of its physicochemical property are represented by the determination of critical micelle concentration (cmc). The cmc value of the amphiphile was 9.4 × 10−5 mol·dm−3. The evaluation of environmental toxicity was performed on a daphnid species Simpocephalus expinosus s.l., which was very sensitive to primulic acids 1. The results from acute immobilisation test show that the tested compound has half maximal effective concentration after 24 hours (EC50-24 h) equal to 6.9 mg·l−1. Saponin can be classified as a toxic compound for aquatic organisms. more...
- Published
- 2020
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5. Evaluation of Manganese Chloride’s Effect on Biosynthetic Properties of In Vitro Cultures of Eschscholzia californica Cham.
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Andrea Balažová, Júlia Urdová, František Bilka, Ivana Holková, Branislav Horváth, Vladimír Forman, and Pavel Mučaji
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benzophenantridine alkaloids ,berberine bridge enzyme ,(S)-N-methylcoclaurine-3′-hydroxylase ,3′-hydroxy-N-methyl-(S)-coclaurine 4′-O-methyltransferase ,lipoxygenase ,Abiotic elicitation ,Eschscholzia californica Cham. ,manganese chloride ,Organic chemistry ,QD241-441 - Abstract
The basal production of secondary metabolites in medicinal plants is limited. One of the effective approaches that encourages plants to produce a remarkable amount of precious compounds is an application of elicitors. Our work was focused on the elicitation of Eschscholzia californica Cham. suspension cultures using various concentrations of MnCl2 (5; 10; 15 mg/L) with the aim of evaluating its effect on sanguinarine, chelerythrine, and macarpine production and gene expression of enzymes involved in the biosynthesis of mentioned secondary metabolites (BBE, 4′-OMT, CYP80B1) or in defense processes (LOX). Suspension cultures were exposed to elicitor for 24, 48, and 72 h. The content of alkaloids in phytomass was determined on the basis of their fluorescence properties. The relative mRNA expression of selected genes was analyzed using the ΔΔCt value method. PCR products were evaluated by melting curve analysis to confirm the specific amplification. Our results demonstrated that Eschscholzia californica Cham. cell suspension cultures evince sensitivity to the presence of MnCl2 in growth media resulting in the increased production of benzophenanthridine alkaloids and gene expression of selected enzymes. Manganese chloride seems to be a potential elicitor supporting natural biosynthetic properties in plant cell cultures and can be applied for the sustained production of valuable secondary metabolites. more...
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- 2018
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6. Nicotinamide-based supergelator self-assembling via asymmetric hydrogen bonding NH⋯OC and H⋯Br
- Author
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Peter, Kasak, Peter, Hrobárik, Josef, Osička, Dominika, Soláriková, Branislav, Horváth, Jan, Tkac, Kishor K, Sadasivuni, Mariam A, AlMaadeed, and Roman, Mikláš
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Molecular Weight ,Niacinamide ,Solvents ,Hydrogen Bonding ,Gels - Abstract
Development of highly efficient low-molecular weight gelators (LMWGs) for safe energy storage materials is of great demand. Energy storage materials as fuel gels are often achieved by construction of hybrid organic frameworks capable of multiple noncovalent interactions in self-assembly, which allow tuning required properties at the molecular level by altering individual building blocks of the LMWG. However, LMWGs have limited rechargeable capability due to their chemical instability.We designed, synthesized and characterized a novel, bio-inspired chiral gemini amphiphile derivative 1 containing N-hexadecyl aliphatic tails from quaternized nicotinamide-based segment and bromide anion showing supergelation ability in water, alcohols, aprotic polar and aromatic solvents, with critical gel concentrations as low as 0.1 and 0.035 wt% in isopropanol and water, respectively.Nanostructural architecture of the network depended on the solvent used and showed variations in size and shape of 1D nanofibers. Supergelation is attributed to a unique asymmetric NH⋯OC, H⋯Br more...
- Published
- 2021
7. Novel sulfonamides incorporating 1,3,5-triazine and amino acid structural motifs as inhibitors of the physiological carbonic anhydrase isozymes I, II and IV and tumor-associated isozyme IX
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Branislav Horváth, Peter Mikuš, Claudiu T. Supuran, Dominika Krajčiová, Andrea Angeli, Mária Bodnár Mikulová, Vladimír Garaj, Daniel Pecher, and Silvia Bua
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0301 basic medicine ,Carbonic Anhydrase I ,Molecular model ,Stereochemistry ,Cyanuric chloride ,Carbonic Anhydrase II ,Biochemistry ,Isozyme ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,Carbonic Anhydrase IV ,0302 clinical medicine ,1,3,5-Triazine ,Carbonic anhydrase ,Drug Discovery ,Nucleophilic substitution ,Humans ,Amino Acids ,Carbonic Anhydrase Inhibitors ,Molecular Biology ,chemistry.chemical_classification ,Sulfonamides ,Molecular Structure ,biology ,Triazines ,Organic Chemistry ,Amino acid ,Molecular Docking Simulation ,030104 developmental biology ,chemistry ,Docking (molecular) ,030220 oncology & carcinogenesis ,biology.protein - Abstract
A new series of thirty s-triazinyl-substituted aminoalkylbenzenesulfonamides, incorporating a symmetric pair of amino acid moieties, is reported, together with inhibition studies of physiologically relevant human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms. Specifically, against the cytosolic hCA I, II, transmembrane hCA IV and the tumor-associated, membrane-bound hCA IX. The compounds were prepared by nucleophilic substitution of chlorine atoms from cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) using environmentally friendly water-based synthetic conditions. The products yields ranged in the interval of 43–97%. Purity of the products was verified by the HPLC-DAD-ESI-Q-TOF MS method. Identity of the products was confirmed by the same method plus NMR and IR. The products showed weak inhibition of the cytosolic, off-target isozyme hCA II, but some of them were low nanomolar (i.e. strong) inhibitors of the tumor-associated hCA IX. The series offered representatives selective towards isozymes hCA I, IV and IX. 2,2′-((6-((4-sulfamoylphenethyl)amino)-1,3,5-triazine-2,4-diyl)bis(imino))disuccinic acid demonstrated highest selectivity to the tumor-associated isoform hCA IX over off-target isozymes, with impressive KI ratio (hCA II/hCA IX) 213.9 and inhibition constant equal to acetazolamide (KI = 25.8 nM). Although the selectivities of some other products, e.g. those conjugating Leu and Glu, were a bit lower (188.7 and 84.3, respectively) their inhibition constants were similar to acetazolamide too (24.0 and 27.1, respectively). The selected most impressive results from the inhibition study were interpreted via molecular modeling experiment (docking in Glide) revealing different inter-molecular enzyme-substrate interaction of 2,2′-((6-((4-sulfamoylphenethyl)amino)-1,3,5-triazine-2,4-diyl)bis(imino))disuccinic acid within specific hCA IX and hCA II microregions. Therefore, several selected compounds from this study can be considered as highly effective and selective inhibitors of hCA IX, worthy to further (preclinical) investigation. more...
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- 2018
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8. CAN-based oxidative annulation of alkenols with 1,3-dicarbonyl compounds
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Jan Světlík, Branislav Horváth, Dariusz Cież, and Krzysztof Kozieł
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Annulation ,010405 organic chemistry ,Chemistry ,General Chemistry ,Oxidative phosphorylation ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,Radical cyclization ,0104 chemical sciences - Abstract
A mild protocol for the reaction of 1,3-dicarbonyl compounds with a range of alkenols mediated by CAN was described. The oxidative free radical cyclization leading to corresponding dihydrofuran derivatives tolerated the presence of hydroxyl group. more...
- Published
- 2018
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9. Improved isolation of betulin and lupeol from birch bark and oxidation of their acetylated derivatives with chromyl chloride
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Martin Pisárčik, Branislav Horváth, Miloš Lukáč, Renáta Horáková, and Ferdinand Devínsky
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chemistry.chemical_classification ,Betulin ,010405 organic chemistry ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Aldehyde ,0104 chemical sciences ,Terpene ,chemistry.chemical_compound ,chemistry ,Acetylation ,visual_art ,parasitic diseases ,visual_art.visual_art_medium ,Moiety ,Organic chemistry ,Bark ,Chromyl chloride ,Lupeol - Abstract
An improved method of isolation of betulin and lupeol from birch bark is developed and reported. The method afforded triterpenes with purity of 98.2% (betulin) and 96.3% (lupeol), respectively. Chromyl chloride was also investigated as an oxidating agent of O-acetylated betulin and lupeol. The transformation of isopropenyl moiety to aldehyde group was observed. more...
- Published
- 2018
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10. The Synthesis, Self-Assembled Structures, and Microbicidal Activity of Cationic Gemini Surfactants with Branched Tridecyl Chains
- Author
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Branislav Horváth, Miloš Lukáč, Ferdinand Devínsky, Marián Bukovský, Matúš Pupák, Martin Pisárčik, and Lukáš Hubčík
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Chemical Phenomena ,Pharmaceutical Science ,Chemistry Techniques, Synthetic ,Microbial Sensitivity Tests ,Micelle ,Article ,Analytical Chemistry ,chemistry.chemical_compound ,Structure-Activity Relationship ,Surface-Active Agents ,zeta potential ,Pulmonary surfactant ,Anti-Infective Agents ,Drug Discovery ,Polymer chemistry ,Zeta potential ,Physical and Theoretical Chemistry ,Methylene ,Alkyl ,chemistry.chemical_classification ,gemini surfactant ,Aqueous solution ,Dose-Response Relationship, Drug ,Organic Chemistry ,Cationic polymerization ,Electric Conductivity ,polymethylene spacer ,microbicidal activity ,tridecyl chain ,Quaternary Ammonium Compounds ,Solutions ,chemistry ,Chemistry (miscellaneous) ,Critical micelle concentration ,Molecular Medicine - Abstract
Cationic gemini surfactants with polymethylene spacer and linear alkyl chains containing an even number of carbon atoms have been extensively studied in the recent past, with the emphasis put on the determination of their aggregation behaviour in aqueous solution and their biological properties. However, the information on the aggregation of branched gemini surfactants with an odd number of carbon atoms in their alkyl chains is only sparsely reported in the literature. To help cover this gap in the research of cationic gemini surfactants, a series of branched bisammonium cationic gemini surfactants with an odd number of carbon atoms in alkyl chains (tridecane-2-yl chains) and a polymethylene spacer with a variable length ranging from 3 to 12 carbon atoms have been synthesized and investigated. Critical micelle concentration, which was determined by three methods, was found to be in the order 10&minus, 4 mol/L. A comparison of the obtained data of the novel series of tridecyl chain geminis with those of gemini surfactants with dodecyl chains and an identical spacer structure revealed that structural differences between both series of gemini surfactants result in different aggregation and surface properties for surfactants with 6 and 8 methylene groups in the spacer (N,N&rsquo, bis(tridecane-2-yl)-N,N,N&rsquo, N&rsquo, tetramethylhexane-1,6-diaminium dibromide and N,N&rsquo, tetramethyloctane-1,8-diaminium dibromide) with the cmc values 8.2 ×, 10&minus, 4 mol/L and 6.5 ×, 4 mol/L, respectively, as determined by surface tension measurements. Particle size analysis showed the formation of small stable spherical micelles in the interval between 2.8 and 5 nm and with zeta potential around +50 mV, which are independent of surfactant concentration and increase with the increasing spacer length. Microbicidal activity of 13-s-13 gemini surfactants was found to be efficient against Gram-positive, Gram-negative bacteria and yeast. more...
- Published
- 2019
11. Novel Phospholium‐Type Cationic Surfactants: Synthesis, Aggregation Properties and Antimicrobial Activity
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Aspasia Papapetropoulou, Marián Bukovský, Ferdinand Devínsky, Branislav Horváth, Martin Pisárčik, and Miloš Lukáč
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chemistry.chemical_classification ,010405 organic chemistry ,General Chemical Engineering ,Cationic polymerization ,010402 general chemistry ,01 natural sciences ,Micelle ,0104 chemical sciences ,Surfaces, Coatings and Films ,Surface tension ,chemistry.chemical_compound ,chemistry ,Dynamic light scattering ,Critical micelle concentration ,Polymer chemistry ,Amphiphile ,Organic chemistry ,Phosphonium ,Physical and Theoretical Chemistry ,Alkyl - Abstract
A series of novel phospholium amphiphilic compounds with straight alkyl chains with different numbers of carbon atoms (12, 14, 15, 16, 17, 18) were synthesized. The quaternary phosphorus, phosphonium cation, is incorporated into a five-membered heterocyclic ring. Their physicochemical properties were investigated by measurements of surface tension, conductivity and dynamic light scattering. The critical micelle concentration (c M), the surface tension value at the c M (γ cmc), the surface area at the surface saturation per head group (A cmc), the ionization degree of micelle (α), the free energy of micellization (ΔG° mic), and hydrodynamic diameter (d h) were determined. Antimicrobial activity was tested against bacteria and yeast. The structure–activity relationship was determined. more...
- Published
- 2016
- Full Text
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