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Search results for: PYRAZINE-BASED DERIVATIVES
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Efficient synthesis of orthogonally protected spermidine and norspermidine derivatives
PublicationOtrzymano 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
PublicationW 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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Hedging Strategies of Derivatives Instruments for Commodity Trading Entities
PublicationHedging 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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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublicationNew 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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Hydration of urea and its derivatives - Volumetric and compressibility studies
PublicationThe 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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Copper(I) iodide ribbons coordinated with thiourea derivatives
PublicationTwo 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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Extracting functional groups of ALLINI to design derivatives of FDA‐approved drugs: Inhibition of HIV‐1 integrase
PublicationHIV‐1 integrase (IN) is crucial for integration of viral DNA into the host genome and a promising target in development of antiretroviral inhibitors. In this work, six new compounds were designed by linking the structures of two different class of HIV‐1 IN inhibitors (active site binders and allosteric IN inhibitors (ALLINIs)). Among newly designed compounds, INRAT10b was found most potent HIV‐1 IN inhibitor considering different...
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Analysis of bisphenols and their derivatives in infant and toddler ready-to-feed milk and powdered milk by LC MS/MS
PublicationReady-to-feed milk and powdered milk packed in different types of packaging lined with resin are chosen as the primary or complementary diet for infants and toddlers. An HPLC–MS/MS method was established and validated for the determination of nineteen bisphenols and their derivatives in such samples. The recoveries were from 31% to 120%, while the values of limit of detection and quantification were in the range of 0.24–0.40 and...
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Isolation of xanthone and benzophenone derivatives from Cyclopia genistoides (L.) Vent. (honeybush) and their pro-apoptotic activity on synoviocytes from patients with rheumatoid arthritis
PublicationA fast and efficient method for the isolation of the C-glucosidated xanthones mangiferin and isomangiferin from the South-African plant Cyclopia genistoides was developed for the first time. Two benzophenone derivatives: 3-C-β-glucosides of maclurin and iriflophenone, were isolated from C. genistoides extracts using semi-preparative. The structures of the compounds were determined by 1D and 2D NMR experiments and/or LC-DAD-ESI–MS.
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Enhanced Activity of P4503A4 and UGT1A10 Induced by Acridinone Derivatives C-1305 and C-1311 in MCF-7 and HCT116 Cancer Cells: Consequences for the Drugs’ Cytotoxicity, Metabolism and Cellular Response
PublicationActivity modulation of drug metabolism enzymes can change the biotransformation of chemotherapeutics and cellular responses induced by them. As a result, drug-drug interactions can be modified. Acridinone derivatives, represented here by C-1305 and C-1311, are potent anticancer drugs. Previous studies in non-cellular systems showed that they are mechanism-based inhibitors of cytochrome P4503A4 and undergo glucuronidation via UDP-glucuronosyltranspherase...
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Dipodal Tetraamide Derivatives of 1,10-Diaza-18-Crown-6 and Alkylmalonic Acids—Synthesis and Use as Ionophores in Ion Selective Membrane Electrodes
PublicationNovel dipodal derivatives of an 18-membered diaza-crown ether with two diamide chains featuring methylmalonic or butylmalonic acid residues were obtained and tested as ionophores in ion-selective plasticized membrane electrodes. The objective of the study was to identify measurement conditions which ensure the most favorable performance for magnesium ion-selective electrodes. The relationship between the molar lipophilic anion...
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Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublicationA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
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Development of Sulfamoylated 4‑(1-Phenyl‑1H‑1,2,3-triazol-4-yl)phenol Derivatives as Potent Steroid Sulfatase Inhibitors for Efficient Treatment of Breast Cancer
PublicationWe present here the advances achieved in the development of new sulfamoylated 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives as potent steroid sulfatase (STS) inhibitors for the treatment of breast cancer. Prompted by promising biological results and in silico analysis, the initial series of similar compounds were extended, appending a variety of m-substituents at the outer phenyl ring. The inhibition profiles of the newly...
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5-Selenocyanato and 5-trifluoromethanesulfonyl derivatives of 2′-deoxyuridine: synthesis, radiation and computational chemistry as well as cytotoxicity
Publication5-Selenocyanato-2′-deoxyuridine (SeCNdU) and 5-trifluoromethanesulfonyl-2′-deoxyuridine (OTfdU) have been synthesized and their structures have been confirmed with NMR and MS methods. Both compounds undergo dissociative electron attachment (DEA) when irradiated with X-rays in an aqueous solution containing a hydroxyl radical scavenger. The DEA yield of SeCNdU significantly exceeds that of 5-bromo-2′-deoxyuridine (BrdU), remaining...
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Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
PublicationDesign automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has...
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Alkylation of 9-substituted guanine derivatives with α,ω-dihaloalkanes
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Photophysics of 7-Hydroxytetrahydroisoquinoline-3-carboxylic Acid and Its Derivatives
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The content of butyl- and phenyltin derivatives in the sediment from the Port of Gdansk
PublicationPróbki 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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Prediction of antimicrobial activity of imidazole derivatives by artificial neural networks
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Antimicrobial and surface activity of 1-alkyl-3-methylimidazolium derivatives
PublicationWiedza 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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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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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
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Synthesis of ester derivatives of propylene glycol in the presence of zinc carboxylates.
PublicationZbadano 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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Numerical Estimation of Hull Hydrodynamic Derivatives in Ship Maneuvering Prediction
PublicationPrediction 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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Fractional Problems with Right-Handed Riemann-Liouville Fractional Derivatives
PublicationIn 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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Formulation of Time-Fractional Electrodynamics Based on Riemann-Silberstein Vector
PublicationIn this paper, the formulation of time-fractional (TF) electrodynamics is derived based on the Riemann-Silberstein (RS) vector. With the use of this vector and fractional-order derivatives, one can write TF Maxwell’s equations in a compact form, which allows for modelling of energy dissipation and dynamics of electromagnetic systems with memory. Therefore, we formulate TF Maxwell’s equations using the RS vector and analyse their...
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Extraction and Analysis of Bisphenols and Their Derivatives in Infant and Toddler Ready-to-feed Meals by Ultrasound-assisted Membrane Extraction Followed by LC MS/MS
PublicationThis research developed an ultrasound-assisted membrane extraction coupled with liquid chromatography-tandem mass spectrometry method for the determination of nineteen bisphenols and their derivatives in infant and toddler ready-to-feed meals. The calibration curves for all analytes were linear in the tested range, and the limit of detection and limit of quantitation were in the range 0.27 to 0.79 ng/g and 0.80 to 2.4 ng/g, respectively....
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A novel version of simulated annealing based on linguistic patterns for solving facility layout problems
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Synthesis and biological evaluation of fluorinated N-benzoyl and N-phenylacetoyl derivatives of 3-(4-aminophenyl)-coumarin-7-O-sulfamate as steroid sulfatase inhibitors
PublicationIn the present work, we report convenient methods for the synthesis of 3-(4-aminophenyl)-coumarin-7-O-sulfamate derivatives N-acylated with fluorinated analogues of benzoic or phenylacetic acid as steroid sulfatase (STS) inhibitors. The design of these potential STS inhibitors was supported by molecular modeling techniques. Additionally, computational docking methods were used to determine the binding modes of the synthesized inhibitors...
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Fentanyl and its derivatives as a group of new psychoactive substances (designer drugs)
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In vitro and in vivo biological activities of azulene derivatives with potential applications in medicine
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Amine–alkyl derivatives of hydantoin: New tool to combat resistant bacteria
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublicationNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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Antimicrobial activity of 5-arylidene aromatic derivatives of hydantoin. Part 2
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Kinetics of Flavoenzyme-Catalyzed Reduction of Tirapazamine Derivatives: Implications for Their Prooxidant Cytotoxicity
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Determination of the Stereostructure of Pyrimidine Nucleoside Derivatives with a Combination of Various Chiroptical Methods
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Synthesis of conjugates of Combretastatin A-4 with tuftsin derivatives as potential anticancer agents
PublicationZaprezentowano syntezę nowych koniugatów Combretastatyny A-4 z pochodnymi tuftsyny i retro-tuftsyny, jako potencjalnych związków przeciwnowotworowych.
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Reaction of thio and seleno phosphoric acid derivatives with O-thioacylated hydroxylamine
PublicationZbadano reakcję siarkowych i selenowych analogów kwasu O,O-neopentylidenofosforowego z O-tiopiwaloilo-N-tert-butylohydroksyloaminą, w której to następuje rozszczepienie wiązania N-O. Znaleziono korelację pomiędzy potencjałem utleniającym anionu pochodnej kwasu fosforowego a przebiegiem badanej reakcji.
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Synthesis of conjugates of amino-combretastatin with tuftsin derivatives as potential anticancer agents
PublicationOpisano syntezę nowych koniugatów 3'-N-(tuftsyno lub retro-tuftsyno)-amino-kombretastatyny jako potencjalnych związków przeciw-nowotworowych. Do syntezy amino-kombretastatyny (amino-CA-4) wykorzystano reakację Wittiga a koniugatów metodę DPPA. Mamy nadzieję, że połączenie pochodnych tuftsyny z amino-CA-4 wpłynie na polepszenie właściwości terapeutycznych CA-4.
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Artificial Neural Networks for Prediction of Antibacterial Activity in Series of Imidazole Derivatives
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Anti-Helicobacter pylori activity of some newly synthesized derivatives of xanthone
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Spectroscopic insight into supramolecular assemblies of boric acid derivatives and β-cyclodextrin
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Effect of renal replacement therapy on selected arachidonic acid derivatives concentration
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Solvent extraction of copper ions by 3-substituted derivatives of β-diketones
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Fully scalable one-pot method for the production of phosphonic graphene derivatives
PublicationGraphene oxide was functionalized with simultaneous reduction to produce phosphonated reduced graphene oxide in a novel, fully scalable, one-pot method. The phosphonic derivative of graphene was obtained through the reaction of graphene oxide with phosphorus trichloride in water. The newly synthesized reduced graphene oxide derivative was fully characterized by using spectroscopic methods along with thermal analysis. The morphology...
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Electrochemical simulation of enzymatic transformations studied for the selected antitumor acridine derivatives
PublicationThe elucidation of the metabolic pathways and the biotransformation mechanisms of potential drugs is a crucial point in drug development. It allows to know the activation routes of the new biologically active compounds, especially in respect to their possible toxicity. Generally, in vivo or in vitro experiments with liver microsomes or hepatocytes are performed. However, these testing schemes are tedious, time consuming and of...
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Synthesis and Study of Antifungal Properties of New Cationic Beta-Glucan Derivatives
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The FMO analysis of the molecular interaction of fentanyl derivatives with the μ-opioid receptor
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Recent Trends in the Application of Chromatographic Techniques in the Analysis of Luteolin and Its Derivatives
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