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Wyniki wyszukiwania dla: polyunsaturated fatty acids
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Chemistry induced by low-energy electrons in condensed multilayers of pure small organic acids
PublikacjaPrzedstawiono reakcje indukowane przez niskoenergetyczne elektrony (0.7 - 20 eV) w kondensowanych warstwach kwasu mrówkowego (HCOOH), częściowo deuterowanego kwasu octowego (CH3COOD) oraz kwasu trifluorooctowego (CF3COOD).
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Lawesson's reagent (LR) for direct thionation of hydroxamic acids. Substituent effect on LR reactivity
PublikacjaOkreślono zakres stosowalności i ogranicznia metody bezpośredniej tionacji kwasów hydroksamowych (HAA) za pomocą odczynnika Lawessona (LR). Przedmiotem badań było 35 HAA o wzorze ogólnym R1CON(R2)OH gdzie: R1 = alkil, aryl, benzyl, etoksykarbonylometylen, cynamyl, heteroaryl, a R2 = alkil, aryl. Ustalono, że wydajności kwasów tiohydroksamowych są niskie, gdy wyjściowy HAA posiada w swojej strukturze duże objętościowo reszty R1...
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Synthesis of disubstituted 1,3,4,9-tetrahydropyrano-[3,4-b]indole-1-acetic acids derivatives
Publikacja1,3,4,9-tetrahydropyrano[3,4-b ]indole-1-acetic acid derivatives are of interest for pharmaceutical research as a core structure for synthesis of biological active substance - Etodolac (selective Cyclooxygenase-2 inhibitor, which belongs to the Non-steroidal Anti-inflammatory Drug, NSAID, that shows a clin-ically effective analgesic and anti-inflammatory activity). Here the way of synthesis of two 1,3,4,9-tetrahydropyrano[3,4-b...
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Calculations of electron impact ionization cross section for simple biomolecules: formic and acetic acids
PublikacjaObliczono przekroje czynne na jednokrotną jonizację kwasu mrówkowego oraz kwasu octowego. Obliczenia przeprowadzono używając formalizmu BEB w zakresie energii od progu na jonizację do 400 eV. Wyniki porównano z dostępnymi danymi doświadczalnymi.
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Distinguishing of cocrystals from simple eutectic mixtures: phenolic acids as potential pharmaceutical coformers
PublikacjaThe multiparameter model comprising 1D and 2D QSPR/QSAR descriptors was proposed and validated for phenolic acid binary systems. This approach is based on the optimization of regression coefficients for maximization of the percentage of true positives in the pool of systems comprising either simple binary eutectics or cocrystals. The training set consisted of 58 eutectics and 168 cocrystals. The solid dispersions collection used...
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Photocatalytic mineralisation of humic acids using TiO2 modified by tungsten dioxide/ hydrogen peroxide
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An improved preparation of N2-tert-butoxycarbonyl- and N2-benzyloxycarbonyl-(S)-2,4-diaminobutanoic acids.
PublikacjaN-Benzyloksykarbonylo i N-tert-butoksykarbonylo-(S)-asparaginę przekształcono do odpowiednio chronionego kwasu (S)-2,4-diaminobutanowego z dobrą wydajnością, w reakcji z octanem jodobenzenu w temp. 0 st.C w mieszaninie tetrahydrofuranu i wody.
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Optical activity of the guest azobenzene molecule generated by inclusion complexation with steroidal bile acids.
PublikacjaZsyntetyzowano krystaliczne kompleksy inkluzyjne azobenzenu z kwasami cholowym i deoksycholowym. Otrzymane związki inkluzyjne poddano badaniom przy wykorzystaniu spektroskopii dichroizmu kołowego w fazie stałej (KBr). Dodatni efekt Cottona, odpowiadający niskoenergetycznemu przejściu elektronowemu n-pi*, skorelowano z helikalnością M,M skręconej cząsteczki azobenzenu. Ponadto w celach porównawczych zmierzono dichroizm kołowy w...
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Thermal Decomposition of Carbamoyl Meldrum’s Acids: A Starting Point for the Preparation of 1,3-Oxazine Derivatives
PublikacjaThe ability to undergo [4 + 2] versus [2 + 2] cycloaddition was under investigation for ketenes thermally generated from carbamoyl Meldrum’s acid. Usually, 1,3-oxazino-5-carbamoylo-4,6-diones are formed when carbamoyl Meldrum’s acid reacts with imine. However, in some cases, a reaction takes an unexpected course, leading to the formation of tetraponerines alkaloids derivatives or cyclic iminoethers.
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Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy
PublikacjaAlcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures...
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Statistical optimization of the synthesis of plant-derived fatty acid esters of TMP over homogeneous organometallic tin catalyst
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Ultrashort Cationic Lipopeptides–Effect of N-Terminal Amino Acid and Fatty Acid Type on Antimicrobial Activity and Hemolysis
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Fatty Acid Profile, Health Lipid Indices, and Sensory Properties of Meat from Pekin Ducks of Different Origins
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Carboxymethyl Starch/Medium Chain Fatty Acid Compositions: Rheological Changes During Storage and Selected Film Properties
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Effects of Three-Month Feeding High Fat Diets with Different Fatty Acid Composition on Myocardial Proteome in Mice
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Rapid ion-exchange matrix removal for a decrease of detection limits in the analysis of salt-rich reservoir waters for fluorobenzoic acids by liquid chromatography coupled with tandem mass spectrometry
PublikacjaA matrix removal procedure with ion-exchange resin prior to analysis for 18 fluorinated benzoic acids (FBAs) tracers in saline (>25% salt) reservoir water was optimized. The elimination of >98% of salt and the simultaneous matrix sample cleanup allowed the direct analysis using the supernatant by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This resulted in a gain in detection limits for most of the tracers...
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Determination of free tyrosine in equestrian supplements by LC–MS/MS and comparison of its quantity with total free amino acids content in view of doping control
PublikacjaThe reports on the probable beneficial impact of tyrosine (TYR) supplementation on performance enhancement have contributed to the growth of interest in TYR in equestrian sports field and related industries, such as the manufacture of dietary and nutritional supplements. In this study, the first attempt to the assessment of horses exposure to TYR during nutritional supplementation was demonstrated by quantification of unbound TYR...
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The Physicochemical and Antibacterial Properties of Chitosan-Based Materials Modified with Phenolic Acids Irradiated by UVC Light
PublikacjaThis paper concerns the physicochemical properties of chitosan/phenolic acid thin films irradiated by ultraviolet radiation with wavelengths between 200 and 290 nm (UVC) light. We investigated the preparation and characterization of thin films based on chitosan (CTS) with tannic (TA), caffeic (CA) and ferulic acid (FA) addition as potential food‐packaging materials. Such materials were then exposed to the UVC light (254 nm) for...
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Spectral Characteristic and Preliminary Anticancer Activity in vitro of Selected Rhodanine‐3‐carboxylic Acids Derivatives
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The influence of different acids and pepsin on the extractability of collagen from the skin of Baltic cod (Gadus morhua)
PublikacjaZastosowano 5,0 M roztwory kwasu cytrynowego, mlekowego, octowego oraz 0,115 M roztwór kwasu solnego. Kolagen z całych skór ekstrahowano w 4 st.C odpowiednimi kwasami (1 : 6, w/v) w czasie 24, 48 i 72 h. Stwierdzono, że kwas solny jest najmniej efektywnym rozpuszczalnikiem kolagenu spośród użytych kwasów. W zastosowanych warunkach doświadczeń maksymalnie można wyekstrahować kwasem cytrynowym 60 % kolagenu, kwasem octowym i mlekowym...
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On the origin of surface imposed anisotropic growth of salicylic and acetylsalicylic acids crystals during droplet evaporation
PublikacjaIn this paper droplet evaporative crystallization of salicylic acid (SA) and acetylsalicylic acid (ASA) crystals on different surfaces, such as glass, polyvinyl alcohol (PVA), and paraffin was studied. The obtained crystals were analyzed using powder X-ray diffraction (PXRD) technique. In order to better understand the effect of the surface on evaporative crystallization, crystals deposited on glass were scraped off. Moreover,...
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The Physicochemical, Antioxidant, and Color Properties of Thin Films Based on Chitosan Modified by Different Phenolic Acids
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Substituent effects on ^15N NMR chemical shifts in selected N-alkylthiohydroxamic acids. A comparative study
PublikacjaNa podstawie widm 15N NMR przeanalizowano wpływy podstawników wybranych kwasów tiohydroksamowych na przesunięcia chemiczne N-15. Analiza porównawcza z przesunięciami chemicznymi strukturalnie podobnych amidów, tioamidów i kwasów hydroksamowych pozwoliła na stwierdzenie, że nie zatłoczenie steryczne a grupa N-OH jest odpowiedzialna za osłabienie efektów odsłaniających zarówno podstawników bezpośrednio związanych z atomem azotu jak...
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New reaction of dithiophosphoric acids with O-thioacylhydroxylamines. Nucleophilic substitution or single electron transfer process?
PublikacjaUdowodniono, że dipodstawione lub sterycznie przeszkodzone hydroksyloaminy reagują z przestrzennie rozbudowanymi S-tioacyloditiofosforanami dając odpowiednie O-tioacylohydroksyloaminy. Dalsza reakcja O-tioacylohydroksyloaminy z kwasem ditiofosforowym prowadzi do powstania disiarczku acylowo tiofosfo-rylowego oraz soli amoniowej kwasu ditiofosforowego. Wpływ pułapek rodnikowych na wydajność tej reakcji świadczy dobitnie, że w procesie...
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The stereoselective formation of β-lactams with acyl ketenes generated from 5-acyl-Meldrum's acids
PublikacjaAcyl ketenes formed during thermal decompositions of 5-acyl-2,2-dimethyl-1,3-dioxa-4,6-diones undergo stereoselective [2+2] cycloaddition to chiral aldimines. We report the first example of optically active 3-acyl-β-lactams formation from Meldrum’s acid derivatives.
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The type of blood used to feed Aedes aegypti females affects their cuticular and internal free fatty acid (FFA) profiles
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The Effect of Diets Containing High-Moisture Corn or Triticale Grain on Animal Performance and the Fatty Acid Composition of Lamb Muscles
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Identification of organic acids as potential biomarkers in the urine of autistic children using gas chromatography/mass spectrometry
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The Evaluation of Phenolic Acids and Flavonoids Content and Antiprotozoal Activity of Eryngium Species Biomass Produced by Biotechnological Methods
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On the reaction of bis(phosphothioyl)disulfanes with hydroxamic acids, part I: Ionic versus radical reaction pathways
PublikacjaReaktywność disulfanów bisfosforotiowych jest mało poznana. Wiadomo, że wykazują one aktywność pestycydową związaną z inhibicją acetylocholinesterazy. Z kolei, kwasy hydroksamowe stosuje się jako efektywne środki do detoksykacji trucizn fosforoorganicznych. Zbadano reakcje soli kwasów benzohydroksamowych z elektrofilowymi disulfanami bisfosfonotiowymi. Badania prowadzono z użyciem disulfanów bisfosforo-, bisfosfono- i bisfosfinotiowych....
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GC-FID determination of C2-C4 aliphatic monocarboxylic acids in aqueous samples preceded by solvent extraction
PublikacjaEkstrakcja za pomocą eteru metylo-tert-butylowego (MTBE) została wykorzystana do izolacji krótkołańcuchowych alkanowych kwasów monokarboksylowych (2-4 atomy węgla w cząsteczce) z próbek o matrycy wodnej. Całkowita wydajność dwukrotnej ekstrakcji z próbek wodnych kwasów: octowego, propionowego i masłowego wynosiła odpowiednio ok. 55% , ok. 90% i ponad 90%. Wydajności ekstrakcji są porównywalne z wartościami uzyskiwanymi w przypadku...
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Design, synthesis and structure–activity relationships of novel phenylalanine-based amino acids as kainate receptors ligands
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Plasma Amino Acids May Improve Prediction Accuracy of Cerebral Vasospasm after Aneurysmal Subarachnoid Haemorrhage
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One-step formation of n-alkenyl-malonamides and n-alkenyl-thiomalonamides from carbamoyl meldrum's acids.
PublikacjaA one-pot synthesis for the preparation of N-alkenyl-malonamides and N-alkenyl-thiomalonamides was developed. 5-[Hydroxy/mercapto(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione act as a source of ketenes that react with the tautomeric form of alkyl-(2-phenyl-propylidene)-amines. A possible [2+2] or [4+2] cycloaddition product of ketene to imines was not observed.
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Proton transfer reaction from some C–H acids to N-bases in polar aprotic solvents
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Dodecanol, metabolite of entomopathogenic fungus Conidiobolus coronatus, affects fatty acid composition and cellular immunity of Galleria mellonella and Calliphora vicina
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Effects of Three-Month Administration of High-Saturated Fat Diet and High-Polyunsaturated Fat Diets with Different Linoleic Acid (LA, C18:2n–6) to α-Linolenic Acid (ALA, C18:3n–3) Ratio on the Mouse Liver Proteome
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Impact of humic acids, temperature and stirring on passive extraction of pharmaceuticals from water by trihexyl(tetradecyl)phosphonium dicyanamide
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Taste-active peptides and amino acids of pork meat as components of dry-cured meat products: An in-silico study
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Air-drying temperature changes the content of the phenolic acids and flavonols in white mulberry (Morus alba L.) leaves
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TiO2 Modified with Organic Acids for the Decomposition of Chlorfenvinphos under the Influence of Visible Light: Activity, Performance, Adsorption, and Kinetics
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Bioaccessibility of Phenolic Acids and Flavonoids from Buckwheat Biscuits Prepared from Flours Fermented by Lactic Acid Bacteria
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DEVELOPMENT OF HYDROGEL CAPSULES FOR USE IN DUAL-PHASE TOPICAL PREPARATIONS CONTAINING DIHYDROXYACETONE AND AMINO ACIDS – PRELIMINARY RESULTS
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Effect of Amino Acids and Sodium Chloride on d-Sorbitol in Aqueous Solutions at Different Temperatures: Volumetric and Acoustic Approach
PublikacjaApparent molar volumes and apparent molar compressibilities for d-sorbitol in (0.05, 0.1, 0.2 and 0.3) mol·kg−1 aqueous solutions of l-alanine, l-cysteine and l-histidine and NaCl have been determined from measurements of solution density at T = (288.15, 298.15, 308.15 and 318.15) K and sound velocity at T = 298.15 K, as a function of the concentration of the sugar alcohol. The data were used to obtain the limiting apparent molar...
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The Effect of Long-Term Administration of Fatty Acid Amide Hydrolase Inhibitor URB597 on Oxidative Metabolism in the Heart of Rats with Primary and Secondary Hypertension
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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublikacjaA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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Evaluation of Chemotherapeutic Activity of the Selected Bases’ Analogues of Nucleic Acids Supported by ab initio Various Quantum Chemical Calculations
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Contribution of phenolic acids isolated from green and roasted boiled-type coffee brews to total coffee antioxidant capacity
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Dimolybdenum Tetraacetate as an Auxiliary Chromophore in Absolute Configuration Determination of Amino Acids from their Circular Dichroism Spectra - Foundations and Developments
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Antioxidant Interactions between Major Phenolic Compounds Found in 'Ataulfo' Mango Pulp: Chlorogenic, Gallic, Protocatechuic and Vanillic Acids
PublikacjaPhenolic compounds are known to have antioxidant capacity; however, there is little information about molecular interactions between particular phenolics found in fruits at different developmental stages. Therefore, the total antioxidant capacity of the phenolic compounds of a fruit may not correspond to the sum of individual antioxidant capacity given by antioxidants from that tissue. In this study, individual antioxidant capacity...