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Water chemistry of tundra lakes in the periglacial zone of the Bellsund Fiord (Svalbard) in the summer of 2013
PublicationClimate changes observed in the Arctic (e.g. permafrost degradation, glacier retreat) may have significant influence on sensitive polar wetlands. The main objectives of this paper are defining chemical features of water within six small arctic lakes located in Bellsund (Svalbard) in the area of continuous permafrost occurrence. The unique environmental conditions of the study area offer an opportunity to observe phenomena influencing...
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Environmental characteristics of a tundra river system in Svalbard. Part 2: Chemical stress factors
PublicationBacterial communities in the Arctic environment are subject to multiple stress factors, including contaminants, although typically their concentrations are small. The Arctic contamination research has focused on persistent organic pollutants (POPs) because they are bioaccumulative, resistant to degradation and toxic for all organisms. Pollutants have entered the Arctic predominantly by atmospheric and oceanic long-range transport,...
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Environmental characteristics of a tundra river system in Svalbard. Part 1: Bacterial abundance, community structure and nutrient levels
PublicationThe Arctic hosts a set of unique ecosystems, characterised by extreme environmental conditions and undergoing a rapid change resulting from the average temperature rising. We present a study on an aquatic ecosystem of the Revelva catchment (Spitsbergen), based on samples collected from the lake, river and their tributaries, in the summer of 2016. The landscape variety of the study site and the seasonal change in the hydrological...
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Korporativnaa kul`tura i proekologiceskoe predpriatiem.
PublicationW pracy w kontekście przekształceń form zarządzania środowiskowego w USA uzasadnia sie tezę o potrzebie zmiany podejścia do spraw środowiska z menedżersko-technokratycznego na menedżersko-kulturowe.
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Monitoring of Caged Bluefin Tuna Reactions to Ship and Offshore Wind Farm Operational Noises
PublicationUnderwater noise has been identified as a relevant pollution affecting marine ecosystems in different ways. Despite the numerous studies performed over the last few decades regarding the adverse effect of underwater noise on marine life, a lack of knowledge and methodological procedures still exists, and results are often tentative or qualitative. A monitoring methodology for the behavioral response of bluefin tuna (Thunnus thynnus)...
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Preexisting High Expression of Matrix Metalloproteinase-2 in Tunica Media of Saphenous Vein Conduits Is Associated with Unfavorable Long-Term Outcomes after Coronary Artery Bypass Grafting
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Gelatin-chitosan interactions in edible films and coatings doped with plant extracts for biopreservation of fresh tuna fish products: A review
PublicationThe preservation of tuna fish products, which are extremely perishable seafood items, is a substantial challenge due to their instantaneous spoilage caused by microbial development and oxidative degradation. The current review explores the potential of employing chitosan-gelatin-based edible films and coatings, which are enriched with plant extracts, as a sustainable method to prolong the shelf life of tuna fish products. The article...
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Diversity and distribution of Tardigrada in Arctic cryoconite holes
PublicationDespite the fact that glaciers and ice sheets have been monitored for more than a century, knowledge on the glacial biota remains poor. Cryoconite holes are water-filled reservoirs on a glacier’s surface and one of the most extreme ecosystems for microinvertebrates. Tardigrada, also known as water bears, are a common inhabitant of cryoconite holes. In this paper we present novel data on the morphology, diversity, distribution and...
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Evaluation of the use of reindeer droppings for monitoring essential and non-essential elements in the polar terrestrial environment
PublicationExcess or toxic metals, non-metals and metalloids can be eliminated from the organism by deposition in inert tissue (e.g. fur) or excretion with body secretions, urine and faeces. Droppings are one of the main routes for the elimination of multiple elements and they can be collected without direct contact with the animal. Contaminant concentration has been examined in non-lethally collected tissues of several species (especially...
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The microbial community, its biochemical potential, and the antimicrobial resistance of Enterococcus spp. in Arctic lakes under natural and anthropogenic impact (West Spitsbergen)
PublicationThe sustainable management of small human communities in the Arctic is challenging. In this study, both a water supply system (Lake 1) under the natural impact of a bird-nesting area, and a wastewater receiver (Lake 2) were analysed in the vicinity of the Polish Polar Station on West Spitsbergen. Microbial community composition, abundance and activity were assessed in samples of the treated wastewater, lake water and sediments...
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Computer Support of Analysis of Optical Spectra Measurements
PublicationThe verification of measurement errors has a big impact on the assessment of the accuracy of conducted measurements and obtained results. In many cases, computer simulation results are compared with measurement results in order to evaluate measurement errors. The purpose of our research was to check the accuracy of measurements made with a Fabry–Perot interferometer working in the transmission mode. In the measurement setup, a...
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The role of atmospheric precipitation in introducing contaminants to the surface waters of the Fuglebekken catchment, Spitsbergen.
PublicationAlthough the Svalbard Archipelago is located at a high latitude, far from potential contaminant sources, it is not free from anthropogenic impact. Towards the Fuglebekken catchment, in the southern part of Spitsbergen, north of Hornsund fjord, contaminants can be transported from mainland pollution sources. In the precipitation and surface water collected in the catchment, the following elements were detected and quantified: Ag,...
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Arctic catchment as a sensitive indicator of the environmental changes: distribution and migration of metals (Svalbard)
PublicationArctic regions experience metal pollution, despite their remote location, and the distribution and migration of those metals determine their potential impact on the local environment. Here, a High-Arctic catchment (Revelva, Svalbard) located remotely from human-induced pollution sources is studied with respect to the distribution and migration of chosen trace elements (Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Cs, Mo, Ni, Pb,...
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Synthesis of new antrapyridazone derivatives - a novel group of anticancer agents active on a multidrugresistant(MDR) tumor cell lines
PublicationNovel antrapyridazone derivatives were synthesized and biologically evaluated in order tobroaden the data on structure-activity relationship of this class of cytostatics. Recent literaturedata prove that acetamides react better with aryl chlorides. A new approach based onintroduction of other amides form into aromatic ring in Ullmann was tested. This new methodcould give better yields and make purification step more convenient.
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Unusual behavior of secondary amine group as a leaving group
PublicationIn our recent project we focused on reactivity of2,2-dimethyl-4,6-dioxane-1,3-dione carbamoilo- and thiocarbamoylo- derivatives as a ketenesource. Meldrum`s acid derivatives after thermal decomposition gives substituted keteneswith stoichiometric yield, that can be trapped with various spectrum of nucleophiles likealcohols, thiols, amine, imines etc. In case of5-[3-(dimethylamino)-sulfanyl-propyliden]-2,2-dimethyl-1,3-dioxane-4,6-dione...
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Convenient synthesis of 3-phosphono-β-lactams through the cyclization ofN-alkenyl-phosphonoacetamides
PublicationOxidative cyclization through the treatment by the transition metals is convenientsynthetic tool with a great number of applications. In the most cases the result is the formationof C-C bond between generated radical and unsaturated part of the same or another molecule.As it was presented by Trogolo it is also suitable way to obtain 4-membered heterocyclicβ-lactamic ring[1]. In this communicate we want to present new application...
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Structural and electrochemical heterogeneities of boron-doped diamond surfaces
PublicationThis brief review is focussed on the recent progress in studies of the heterogeneous electrochemical behaviour of various boron-doped materials extending from zero-dimensional particles through polycrystalline or nanostructured three-dimensional surfaces. A boron-doped diamond reveals large heterogeneities induced by numerous factors, inter alia multi-faceted crystallinity, inhomogeneous boron concentration, sp2/sp3-carbon ratio,...
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Surface quality control of a thin SiN layer by optical measurements
PublicationFiber optic interferometers have a wide range of applications, including biological and chemical measurements. Nevertheless, in the case of a reflective interferometer setup, standard silver mirrors cannot be used in every measurement, due to their chemical activity. This work investigates the surface quality of a thin optical layer of silicon nitride (SiN), which can serve as an alternative material for silver mirrors. We present...
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Computer support of analysis optical spectra measurements
PublicationVerification of measurement errors has a big impact on assessment of accuracy of conducted measurements and obtained results. In many cases computer simulation results are compared with measurement results in order to evaluate measurement errors. The purpose of our research was to check the accuracy of measurements made with Fabry-Perot interferometer working in the transmission mode. In measurement setup, a 1310 nm superluminescent...
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Driver fatigue detection method based on facial image analysis
PublicationNowadays, ensuring road safety is a crucial issue that demands continuous development and measures to minimize the risk of accidents. This paper presents the development of a driver fatigue detection method based on the analysis of facial images. To monitor the driver's condition in real-time, a video camera was used. The method of detection is based on analyzing facial features related to the mouth area and eyes, such as...
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Got a Light? Illuminating Lung Cancer
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Metoda doboru parametrów regulatorów położenia i prędkości serwonapędów w układach CNC
PublicationW artykule przedstawiono praktyczną metodę doboru parametrów regulatorów położenia i prędkości, kaskadowego układu regulacji serwonapędów posuwu maszyn numerycznych z interpolatorem generującym zadaną trajektorię z prostokątnym profilowaniem przyspieszenia. Opracowany algorytm doboru parametrów regulatorów uwzględnia m.in. kształt przebiegu sygnału uchybu układu regulacji położenia i rozdzielczość przetwornika do pomiaru położenia...
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Seawater-mixed concretes containing natural and sea sand aggregates – A review
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Materiały sorpcyjne wykorzystywane w maskach ochronnych
PublicationOd zarania dziejów ludzie starają się chronić przed chorobami zakaźnymi, stosując środki ochrony osobistej, do których należą maski ochronne. Z uwagi na obecnie panującą pandemię wirusa SARS-CoV-2, noszenie masek stało się normą w walce z koronawirusem. Jednak zagrożenia dla górnych dróg oddechowych nie stanowią wyłącznie wirusy, lecz również cząstki stałe zawieszone w powietrzu. Szczególnie w krajach wysoko uprzemysłowionych,...
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Simple and novel synthesis of 3-(thio)phosphoryl-β-lactams by radical cyclization
PublicationRadical cyclization of phosphono-acetenamides promoted by manganese(III) acetate leads exclusively to the formation of 3-phosphoryl-β-lactams. The thiophosphoryl analogues were also prepared using this method. In particular, the presented protocol does not require the use of noble metals, while comparable methods do.
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Synthesis of malonylenamides and thiomalonylenamides
Publication5-[Hydroksyl(aryl(amino))methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione is convenient source of ketenes which can be trapped with various nucleophiles like alcohols, thiols and amines. In reaction between in situ generated ketene and enolizable imines we can easily obtain corresponding malonylenamides. This facile method can be used to obtain thiomalonylenamides using 5-[sulfhydrylo(alkyl(amino))methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione...
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One-step formation of n-alkenyl-malonamides and n-alkenyl-thiomalonamides from carbamoyl meldrum's acids.
PublicationA 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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Incorporation of nitrogen in diamond films - A new way of tuning parameters for optical passive elements
PublicationThis paper investigates the impact of nitrogen incorporation in diamond films for the construction of an interferometric sensor to measure displacement. Diamond films with different nitrogen levels (0–5%) were deposited on silicon substrates by microwave plasma enhanced chemical vapor deposition. The structural characteristics of these samples are characterized using scanning electron microscopy (SEM), atomic force microscopy...
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The (de)biasing Effect of GAN-Based Augmentation Methods on Skin Lesion Images
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First Copper(I) and Silver(I) Complexes Containing Phosphanylphosphido Ligands
PublicationThree new complexes with phosphanylphosphido ligands, [Cu4{μ2-P(SiMe3)-PtBu}4](1), [Ag4{μ2-P(SiMe3)-PtBu2}4](2) and [Cu{η1-P(SiMe3)-PiPr2}2]–[Li(Diglyme)2] (3) were synthesized and structurally characterized by X-ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactionsof lithium derivative of diphosphane tBu2P-P(SiMe3)Li·2.7THF withCuCl and [iBu3PAgCl]4, respectively....
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The Specific Nature of Chemical Composition of Water from Volcanic Lakes Based on Bali Case Study
PublicationThe research area was localized in the Indonesian Archipelago, at the latitude of eight and nine degrees S on the one of the Lesser Sunda group island provinces, Bali (563,3 km2). Two massive calderas (Mount Batur 1717 m above sea level.; Mount Sangiyang 2093 m above sea level) are one of the most prominent landforms in the chain of volcanic mountain ranges of the Bali Island. Lake Batur (17,18 km2) and Batur Spring (which are...
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Prognozowanie inflacji przez wybrane banki centralne
PublicationJedne z pierwszych określeń strategii bezpośredniego celu inflacyjnego (BCI) stworzył L.E.O. Svensson kładąc w nim nacisk na prognozę inflacji pełniącą funkcję celu pośredniego. W przedstawieniu tego reżimu z 1996 r. uwzględnił on trzy główne elementy [L.E.O. Svensson 1996, s. 1-3 ]: o ilościowy cel inflacyjny, o procedurę operacyjną uwzględniającą celowanie w prognozę inflacji, którego wewnętrznym warunkiem jest...
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Projekcja inflacji banku centralnego. Na skraju podejścia strategicznego i technicznego
PublicationTematyka książki dotyczy projekcji inflacji publikowanych przez banki centralne wdrażające strategię bezpośredniego celu inflacyjnego (BCI), w szczególności przez Bank Anglii, Norwegii, Szwecji oraz Narodowy Bank Czech. Zagadnienie to ujęto w monografii w ramach trzech zazębiających się obszarów: tworzenia oraz budowy projekcji inflacji, roli, jaką pełnią one w procesie decyzyjnym Komitetów Monetarnych (svenssonowska koncepcja...
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Nauczanie polityki pieniężnej na studiach wyższych - przykłady rozwiązań
PublicationJednym ze sposobów efektywnego nauczania polityki pieniężnej na studiach wyższych jest wykorzystanie studium przypadku. W artykule zaproponowano kilka przykładowych, możliwych do realizacji na ćwiczeniach, zadań opartych na tej metodzie. Te ćwiczenia nastawione są na pracę zespołową. Uczą samodzielnego wyciągania wniosków oraz obrazują związki przyczynowo-skutkowe niezbędne do pełnego zrozumienia materiału. Dodatkowo nabyte przez...
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Can Inflation Forecast and Monetary Policy Path be Really Useful? The Case of the Czech Republic
PublicationProducing and revealing inflation forecast is belie ved to be the best way of implementing a forward-looking monetary policy. The article focuses on inflation forecast targeting (IFT) at the Czech National Bank (CNB) in terms of its efficiency in shaping consumers’ inflation expectations. The goal of the study is to verify the accuracy of the inflation forecasts, and their influence on inflation...
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Adam Smith a pieniądz
PublicationW XVIII wieku Adam Smith opublikował przełomowe dzieło, pt. „Badania nad naturą i przyczynami bogactwa narodów”. Zawarł w nim filary nowej dziedziny nauki, jaką jest ekonomia. Celem artykułu jest określenie wpływu, jakie dzieło A. Smitha wywarło na współczesną teorię pieniądza. Przeprowadzono w nim analizę tekstu A. Smitha z punktu widzenia powstania i cech pieniądza oraz jego koncepcji w ekonomii klasycznej. Analizie poddano rozdział...
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Inflation Forecast or Forecast(s) Targeting?
PublicationThe paper refers to L.E.O. Svensson’s concept of inflation forecast targeting (IFT) and its implementation by central banks of Sweden, Norway and the Czech Republic. The study focuses on (1) inflation forecasts published by selected central banks, i.e.headline inflation and core or monetary policy-relevant (MPR) inflation, which are made on the assumption of endogenous instrument rate, (2) one-year consumer...
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CONSUMERS’ APPROACH TO THE CREDIBILITY OF THE INFLATION FORECASTS PUBLISHED BY CENTRAL BANKS: A NEW METHODOLOGICAL SOLUTION
PublicationModern monetary policy focuses on credibility and shaping inflation expectations. In keeping with the concept of inflation forecast targeting, the inflation forecasts published by central banks play a crucial role in the instrument rate decision-making process and may be treated as a specific intermediate target. This study proposes an inflation forecast credibility index, the scope of which is narrowed to non-specialists’ approach...
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APROKSYMACJE DE VYLDERA PRAWDOPODOBIEŃSTWA RUINY DLA MODELU Z CZASEM CIĄGŁYM W NIESKOŃCZONYM HORYZONCIE CZASOWYM
PublicationArtykuł przedstawia przegląd badań oraz ewolucję aproksymacji De Vyldera. Metoda ta polega na zastąpieniu procesu ryzyka poprzez inny proces ryzyka z wykładniczym rozkładem szkód tak, aby momenty pierwszych trzech rzędów przyrostu dla obu procesów były jednakowe. Idea tego oszacowania została wykorzystana w aproksymacji 4-gamma De Vyldera, w której zastosowano zastąpienie procesu ryzyka procesem ryzyka z rozkładem gamma szkód,...
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The forecasts-based instrument rule and decision making. How closely interlinked? The case of Sweden
PublicationResearch background: The Central Bank of Sweden declared in years 1999–2006 the implementation of the Svensson’s concept of inflation forecast targeting (IFT). It means that the repo rate decision-making process depends on the inflation forecasts. The concept evolved from the strict IFT with the decision-making algorithm called ‘the rule of thumb’ to the flexible IFT. Purpose of the article: The aim of...
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3D Hand Scanning Methodology for Determining Protective Glove Dimensional Allowances
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Perceptual and Motor Effects of Muscle Co-activation in a Force Production Task
PublicationWe tested several predictions of the theory of motor control with spatial referent coordinates related to effects of muscle coactivation on force production and perception. In particular, we predicted that subjects would produce unintentional force increase by finger flexors and be unaware of this force increase. Healthy subjects performed steady force production task in isometric conditions with visual feedback on the force level....
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Magnetic properties of α-KCoPO4 compound with a chiral polar crystal structure
PublicationWe have obtained polycrystalline samples of a metastable α variant of KCoPO4 by low temperature (350–400 °C) solid state metathesis reaction of potassium oxalate and ammonium cobalt orthophosphate. The material crystallizes in a polar chiral structure (sg. P63, no. 173). Measurements of magnetic properties reveal antiferromagnetic interactions and no ordering observed down to T = 1.9 K, well below the Weiss temperature |Θcw| =...
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Preliminary studies on the effect of feed speed on the colour change of wood
PublicationThis paper presents the results of preliminary analyses of the effect of cutting parameters on changes in the colour of wood. Beech wood cut with use circular saw was analysed. The cutting parameter tested was the feed speed, represented by the feed per tooth. Sawing processes with different feed per tooth ranging from 0.0008 mm to 0.09 mm were analysed. It was observed that over the entire range of feed rate per tooth analysed,...
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Structure elucidation of carbamoylo-β-lactam diastereoisomers by ROESY and NOESY experiments
PublicationRecently we have focused in the problem of preparation of carbamoylo-β-lactams as a result of oxidative cyclization of malonyl enamides. In our experiments we obtain mixture of two main β-lactam products: as a result of subsequent elimination and a second as a product of substitution. All of the produced β-lactams have trans configuration what was confirmed by 1H coupling constants. However id should be stressed that in the case...
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Wpływ obecności chlorku trimetylosililu na reakcję syntezy niesymetrycznych malonoamidów
PublicationW trakcie badań nad syntezą niesymetrycznych malonoamidów, optymalizowaliśmy metodę zaproponowaną przez Pak1. Związki te otrzymywaliśmy używając jako substratów 5-(α-amino-α'-hydroksy)-metyleno-pochodnych kwasu Meldruma oraz szeregu różnych amin. W trakcie badań okazało się, że przeprowadzenie syntezy jest możliwe, jeśli jako substrat zastosuje się słabą zasadę. Przy użyciu mocniejszych zasad wydajności reakcji były niskie. Postanowiliśmy...
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Synthesis of 3-Carbamoyl b-Lactams via Manganese(III)-Promoted Cyclization of N-Alkenylmalonamides
PublicationManganese(III)-promoted cyclization of N-alkenylmalonamides (¼N-alkenylpropanediamides) gave 3-(aryl/(alkylamino)carbonyl) b-lactams as well as 3-(aryl/(alkylamino)thiocarbonyl) b-lactams. The relative configuration of the obtained products was unambiguously determined by X-ray crystallography. The proposed method is very useful for the one-pot synthesis of a number of 3-(aryl/ (alkylamino)carbonyl) b-lactams, especially those...
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Manganese(III) Promoted Cyclization of N-alkenyl-N-(2-hydroxyethyl) amides to Iso-Oxacepham Potent β-Lactamase Inhibitors
PublicationBackground: β-Lactams are still a subject of interest of organic chemists. The main reason for this interest is due to their application as a chemotherapeutic. β-Lactam antibiotics are still the most commonly used drugs in bacterial infections. Method: Methods using 4-exo-trig radical cyclization leading to β-lactams are an alternative to classical Staudinger`s β-Lactams formation. We prepared N-alkenyl-N-(2-hydroxyethyl)amides...
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Assessment of the mean time in the therapeutic INR range and the SAME-TT2R2 score in patients with atrial fibrillation and cognitive impairment
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Mechanisms of antimelanoma effect of oat β-glucan supported by electroporation
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