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Wyniki wyszukiwania dla: SCHWARZIAN DERIVATIVE
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Biochemical, Structural Analysis, and Docking Studies of Spiropyrazoline Derivatives
PublikacjaIn this study, we evaluated the antiproliferative potential, DNA damage, crystal struc‐ tures, and docking calculation of two spiropyrazoline derivatives. The main focus of the research was to evaluate the antiproliferative potential of synthesized compounds towards eight cancer cell lines. Compound I demonstrated promising antiproliferative properties, especially toward the HL60 cell line, for which IC50 was equal to 9.4 μM/L....
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Microwave-assisted synthesis of zinc derivatives of potato starch
PublikacjaZincatated potato starch was prepared in a solid-state, microwave-assisted reaction using generated in situ sodium tetrahydroxozincate [Na2Zn(OH)4]. For comparison, zincatation of starch was also carriedout on convectional heating. Depending on the irradiation conditions, the products of either mono- or crosslinking esterification were formed. Higher power applied at shorter exposition offered products ofmonoesterification, and...
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Thermodynamics aspects of interactions between acridine derivatives and DNA
PublikacjaDNA is a molecular target for many anticancer and antiviral drugs. Therefore, a clear understanding of the interaction of small molecules with DNA is important in the rational design of ligands that can bind to DNA with high affinity and selectivity. There are several methods to investigate interactions between drug and DNA. Some of them measure changing into DNA structures, such as lengthening and untwisting of helix of DNA. Other...
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The photophysics of β-homo-tyrosine and its simple derivatives
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Photophysical and theoretical studies of diphenylacetylene derivatives with restricted rotation
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Synthesis of Thermally Stable Energetic 1,2,3-Triazole Derivatives
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Densimetric and ultrasonic characterization of urea and its derivatives in water
PublikacjaW oparciu o pomiary gęstości dla serii roztworów jak i rozpuszczalnika wykonanych w temperaturach 15, 20, 25, 30 i 35oC wyznaczono pozorne molowe objętości mocznika, N-metylomocznika, N,N'-dimetylomocznika, N,N,N',N'-tetrametylomocznika, N-etylomocznika, N,N'-dietylomocznika jak i N-butylomocznika w wodzie. Dodatkowe pomiary szybkości dźwięku przeprowadzone w temperaturze 25oC pozwoliły obliczyć ściśliwości adiabatyczne, pozorne...
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Biological activity of conjugates of muramyl dipeptides with batracylin derivatives
PublikacjaZaprezentowano immunomodulacyjne właściwości nowych koniugatów batracyliny (BAT) z pochodnymi muramylodipeptydów wobec subpopulacji leukocytów krwi obwodowej hodowanych w obecności komórek linii nowotworowych. Leukocyty izolowane były z krwi obwodowej uzyskanej od zdrowych ochotników. Zbadane koniugaty MDP lub nor-MDP z batracyliną wykazały silniejsze własności hamujące proliferację komórek wybranych linii nowotworowych (K562,...
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Synthesis of bicoumarin thiophosphate derivatives as steroid sulfatase inhibitors
PublikacjaBased on the frameworks of 7-hydroxy-2,3-dihydro-1H-cyclopenta[c]chromen-4-one, 3-hydroxy- 7,8,9,10-tetrahydro-6H-benzo[c]chromen-6-one and 3-hydroxy-8,9,10,11-tetrahydro-7H-cyclohepta[c] chromen-6-one, a series of bicoumarin thiophosphate analogs have been synthesized and biologically evaluated. Additionally, their binding modes have been modeled using docking techniques. The inhibitory properties of the synthesized compounds...
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Acyl Meldrum's acid derivatives: application in organic synthesis
PublikacjaThis review is focused on one of the most important classes of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleiophiles. The possible mechanisms of these transformations...
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Hydration of urea and its derivatives - Volumetric and compressibility studies
PublikacjaThe densities and sound velocities at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K have been measured for aqueous solutions of urea, N,N-dimethylurea, N,N-diethylurea, N-propylurea, N-butylurea. From these data the apparent molar volumes, V the apparent molar isentropic compressions, KS,, and the Passynski solvation numbers of solutes have been determined. The concentration dependencies of the calculated quantities, their...
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Hedging Strategies of Derivatives Instruments for Commodity Trading Entities
PublikacjaHedging as an outcome of risk management arises to account several questions. Mentioned aspect of size of the hedging is one of them. Latter questioning refers to whether producer of manufacturer are willing to secure entire exposure, when the hedging should start, now or later in the future, what is the vision on market like direction of market, time of interest, magnitude of exposure, what would be the preferred instruments of...
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Rhodotorulic Acid and its Derivatives: Synthesis, Properties, and Applications
PublikacjaSiderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid, a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, it exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms....
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Copper(I) iodide ribbons coordinated with thiourea derivatives
PublikacjaTwo products of the reactions of CuI with 1-benzoyl-3-(4-bromophenyl)thiourea and with 1-benzoyl-3-(2-iodophenyl)thiourea have been obtained and characterized, namely poly[[[1-benzoyl-3-(4-bromophenyl)thiourea-κS]-µ3-iodidocopper(I)] acetone hemisolvate], {[CuI(C₁₄H₁₁BrN₂OS)]‧0.5C₃H₆O}ₙ, and poly-[µ₄-iodido-µ₃-iodido-[N-(benzo[d]thiazol-2-yl)benzamide-κN]dicopper(I)], [Cu₂I₂(C₁₄H₁₀N₂OS)]ₙ. Their structures, determined by single-crystal...
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On Applications of Elements Modelled by Fractional Derivatives in Circuit Theory
PublikacjaIn this paper, concepts of fractional-order (FO) derivatives are reviewed and discussed with regard to element models applied in the circuit theory. The properties of FO derivatives required for the circuit-level modeling are formulated. Potential problems related to the generalization of transmission-line equations with the use of FO derivatives are presented. It is demonstrated that some formulations of FO derivatives have limited...
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublikacjaNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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Rhodotorulic Acid and its Derivatives: Synthesis, Properties, and Applications
PublikacjaSiderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid (RA), a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, RA exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms....
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Efficient synthesis of orthogonally protected spermidine and norspermidine derivatives
PublikacjaOtrzymano kilka chronionych pochodnych spermidyny i norspermidyny w wyniku reakcji cyjanoetylowania chronionych diamin, ochrony drugorzędowej grupy aminowej oraz redukcji otrzymanego nitrylu za pomocą wodorku litowo-glinowego w temperaturze 0° C.
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Biological activity of conjugates of muramyl dipeptides with batracylin derivatives
PublikacjaW artykule opisano aktywność biologiczną koniugatów muramylo-dipeptydów z batracyliną lub pochodnymi batracyliny. Badania przeprowadzone w Akademii Medycznej w Gdańsku miały na celu oznaczenie immunomodulacyjnych właściwości tych koniugatów wobec subpopulacji leukocytów krwi obwodowej hodowanych w obecności komórek nowotworowych (K562, WEHI164, Ab melanoma). Leukocyty izolowane były z krwi obwodowej uzyskanej od zdrowych ochotników....
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Fractional Variable-Order Derivative and Difference Operators and Their Applications to Dynamical Systems Modelling
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The Effect of Conjugation with Octaarginine, a Cell-Penetrating Peptide on Antifungal Activity of Imidazoacridinone Derivative
PublikacjaAcridine cell-penetrating peptide conjugates are an extremely important family of compounds in antitumor chemotherapy. These conjugates are not so widely analysed in antimicrobial therapy, although bioactive peptides could be used as nanocarriers to smuggle antimicrobial compounds. An octaarginine conjugate of an imidazoacridinone derivative (Compound 1-R8) synthetized by us exhibited high antifungal activity against reference...
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Multiple Solutions to Third-Order Differential Equations with Derivative Dependence and Deviating Arguments
PublikacjaIn this paper, we give some new results for multiplicity of positive (nonnegative) solutions for third-order differential equations with derivative dependence, deviating arguments and Stieltjes integral boundary conditions. We discuss our problem with advanced argument α and arbitrary β ∈ C([0,1],[0,1]), see problem (2). It means that argument β can change the character on [0,1], so β can be delayed in some set J ⊂ [0,1] and advanced...
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Enantioselective sensing of (S)-Thalidomide in blood plasma with a chiral naphthalene diimide derivative
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Apoptosis of human leukemia cells induced by imidazoacridinone derivative C-1311 (Symadex)
PublikacjaPraca dotyczy różnej wrażliwości komórek białaczek ludzkich do ulegania apoptozie pod wpływem pochodnej imidazoakrydonu C-1311, co jest zgodne z aktywnością cytotoksyczną tego związku (EC90) wobec badanych komórek.
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The effect of anthraquinone derivatives on telomerase activity
Dane BadawczeThe data set contains images of the PCR products obtained from the Telomerase Repeated Amplification Protocol (TRAP). The effect of anthraquinone derivatives (TXT1-TXT9) on telomerase activity was comparatively examined using the following reference compounds: BIBR1532, TMPyP4 and mitoxantrone (MTX).
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Alkylation of 9-substituted guanine derivatives with α,ω-dihaloalkanes
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Studies on the influence of β-cyclodextrin derivatives on the physical stability of famotidine
PublikacjaThe usage of Fourier transform infrared spectroscopy, near infrared spectroscopy, differential scanning calorimetry and microscopy is presented in this work focused on the exploration of the effect of CD on the physical stability of famotidine (FAM). The most significant information was achieved by analysis of the second derivatives ofnear infrared (NIR) spectra recorded. Changes in the shape of spectra derivatives allow...
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Photophysics of 7-Hydroxytetrahydroisoquinoline-3-carboxylic Acid and Its Derivatives
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Supramolecular Interactions between β-Cyclodextrin and the Nucleobase Derivatives of Ferrocene
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Conjugation of polyethylenimine and its derivatives to carbon-encapsulated iron nanoparticles
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Natural composites based on polysaccharide derivatives: preparation and physicochemical properties
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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
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The content of butyl- and phenyltin derivatives in the sediment from the Port of Gdansk
PublikacjaPróbki osadów portowych były pobierane dwukrotnie (2003 i 2005)z różnych nabrzeży w Porcie Gdańsk. Rdzenie o długości 25 cm były dzielone na warstwy o grubości 2 i 5cm i po odpowiednim przygotowaniu (w tym także analizie sitowej) były poddawane analizie na zawartość związkow cynoorganicznych.W analizowanych póbkach (o różnej granulacji cząstek osadu) wykryto i oznaczono względnie duże stężenie TBT, DBT, MBT oraz MPhT. Osady portowe...
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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
PublikacjaIn search of new immunosuppressants, mycophenolic acid (MPA) was coupled with amino acid methyl esters followed by hydrolysis to analogs bearing free carboxylic groups. The obtained compunds were tested in vitro as growth inhibitors of lymphoid cell line (Jurkat) and human peripheral blood mononuclear cells (PBMC) from healthy donors. According to obtained results recovering of free carboxylic group increased their activity. Additionally,...
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NUMERICAL ESTIMATION OF HULL HYDRODYNAMIC DERIVATIVES IN SHIP MANOUVERING PREDICTION
PublikacjaOperating in crowded waterways pose a risk of accidents and disasters due to maneuvering limitations of the ship. In order to predict ship’s maneuvering characteristics at the design stage, model tests are often executed as the most accurate prediction tool. Two approaches can be distinguished here: free running model tests and numerical simulations based on planar motion model with the use of hydrodynamic derivatives obtained...
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Numerical Estimation of Hull Hydrodynamic Derivatives in Ship Maneuvering Prediction
PublikacjaPrediction of the maneuvering characteristics of the ship at the design stage can be done by means of model tests, computational simulations or a combination of both. The model tests can be realized as direct simulation of the standard maneuvers with the free running model, which gives the most accurate results, but is also the least affordable as it requires very large tank or natural lake, as well as complex equipment of the...
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New Chalcones Derivatives With Potent Antitumor Activity And Their Metabolism In Vitro
PublikacjaChalcone derivatives exhibit a broad range of biological activities, with antioxidant and cytotoxic properties among the most studied. Despite numerous reports on chalcones as cytotoxic, and potentially anticancer agents, very little is know on their actual mechanism of activity. Generally, chalcones are considered as antimitotic agents, which interfere with tubulin assembly.We have recently developed a new class of chalcones with...
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Antimicrobial and surface activity of 1-alkyl-3-methylimidazolium derivatives
PublikacjaWiedza na temat zależności struktura-aktywność umożliwia projektowanie i syntezę nowych kationowych związków amfifilowych ze zoptymalizowaną aktywnością antymikrobową na rzecz przyszłego rozwoju nowych środków dezynfekujących, sanityzujących czy konserwujących. Potrzeba projektowania i identyfikowania nowych związków posiadających właściwości przeciwbakteryjne jest rezultatem pojawienia się bardziej odpornych mikroorganizmów w...
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Indirect Measurement of Motor Current Derivatives in PMSM Sensorless Drives
PublikacjaMotor current derivatives contain useful information for control algorithms, especially in sensorless electric drives. The measurement of motor current derivatives in electric motors supplied by voltage source inverter can be performed using di/dt transducers. However, in such a solution additional sensors have to be installed, e.g. Rogowski coils. Another approach is to measure current derivatives indirectly – by oversampling...
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Fractional Problems with Right-Handed Riemann-Liouville Fractional Derivatives
PublikacjaIn this paper, we investigate the existence of solutions for advanced fractional differential equations containing the right-handed Riemann-Liouville fractional derivative both with nonlinear boundary conditions and also with initial conditions given at the end point T of interval [0,T ]. We use both the method of successive approximations, the Banach fixed point theorem and the monotone iterative technique, as well. Linear problems...
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Prediction of antimicrobial activity of imidazole derivatives by artificial neural networks
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Immunosuppressive properties of amino acid and peptide derivatives of mycophenolic acid
PublikacjaMycophenolic acid (MPA) was coupled with amino acids and biologically active peptides including derivatives of tuftsin to modify its immunosuppressive properties. Both amino acid unit in the case of simple MPA amides and modifications within peptide moiety of MPA - tuftsin conjugates influenced the observed activity. Antiproliferative potential of the obtained conjugates was investigated in vitro and MPA amides with threonine methyl...
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Expedited antenna optimization with numerical derivatives and gradient change tracking
PublikacjaDesign automation has been playing an increasing role in the development of novel antenna structures for various applications. One of its aspects is electromagnetic (EM)-driven design closure, typically applied upon establishing the antenna topology, and aiming at adjustment of geometry parameters to boost the performance figures as much as possible. Parametric optimization is often realized using local methods given usually reasonable...
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Anticancer Properties of Amino Acid and Peptide Derivatives of Mycophenolic Acid
PublikacjaBackground: Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5’-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent...
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Therapeutic Potential of Carnosine and Its Derivatives in the Treatment of Human Diseases
PublikacjaDespite significant progress in the pathogenesis, diagnosis, treatment, and prevention of cancer and neurodegenerative diseases, their occurrence and mortality are still high around theworld. The resistance of cancer cells to the drugs remains a significant problem in oncology today,while in the case of neuro-degenerative diseases, therapies reversing the process are still yet to be found. Furthermore, it is important to seek new...
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Synthesis of ester derivatives of propylene glycol in the presence of zinc carboxylates.
PublikacjaZbadano wpływ temperatury i stężenia karboksylanów cynku na przebieg estryfikacji glikolu propylenowego kwasami tłuszczowymi. Otrzymano emulgatory, w których maksymalne stężenie monoestru wynosiło 55-57%.
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In vitro photodynamic activity of lipid vesicles with zinc phthalocyanine derivative against Enterococcus faecalis
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Polymeric bisphosphonate derivative of ciprofloxacin – synthesis, structural analysis and antibacterial activity of the prospective conjugate
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CYP3A4 overexpression enhances the cytotoxicity of the antitumor triazoloacridinone derivative C-1305 in CHO cells
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Initial value problems for neutral fractional differential equations involving a Riemann-Liouville derivative
PublikacjaBadano równania neutralne typu ułamkowego z odchylonym argumentem. Podano warunki dostateczne na istnienie jednego rozwiązania.