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Synthesis of conjugates of MDP and nor-MDP linked to tuftsin derivatives as potential immunomodulators
PublikacjaZsyntetyzowano nowe koniugaty muramylodipeptydu (MDP) i nor-muramylo-dipeptydu (nor-MDP) z pochodnymi tuftsyny zawierającymi wiązanie izopeptydowe na epsilon-aminowej grupie lizyny jako potencjalne immunomodulatory. Do syntezy wykorzystano metodę mieszanych bezwodników z chloromrówczanem izobutylu i N-metylomorfoliną w bezwodnym DMF. Końcowe produkty charakteryzowno za pomocą NMR, analizy elementarnej i analizy aminokwasowej na...
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Właściwości fizyczne mieszanek tłuszczowych zawierających olej palmowy.
PublikacjaZbadano właściwości fizyczne mieszanek oleju palmowego z ciekłym lub uwodornionym olejem rzepakowym o różnym składzie procentowym. Zastosowano metodę pulsacyjnego NMR do oznaczenia zawartości fazy stałej, stosując różne metody termostatowania badanych tłuszczów przed analizą. Krzywe topnienia mieszanek tłuszczowych wyznaczono metodą DSC stosując etapy termostatowania analogiczne jak przed oznaczeniem fazy stałej. Zbadano wpływ...
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Modeling of the alcohol dehydrogenase active site. Two different modes of alcohol binding in crystals of zinc and cadmium tri-tert-butoxysilanethiolates evidenced by X-ray diffraction and solid state vibrational spectroscopy
PublikacjaOpisano syntezę, struktury cząsteczkowe oraz widma FT-IR, 1H. 13C, 29Si, 113Cd NMR dziesięciu nowych, mieszanoligandowych kompleksów cynku i kadmu z ligandem tri-tert-butoksysilanotiolanowym i pochodnymi imidazolu. Za pomocą rentgenowskiej analizy strukturalnej i spektroskopii w podczerwieni udokumentowano dwa różne sposoby wiązania etanolu i metanolu w kryształach tych związków. Opisane kompleksy stanowią modele miejsca aktywnego...
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Acid-triggered release from sterically stabilized fusogenic liposomes via ahydrolytic DePEGylation strategy
PublikacjaOpracowano nowe, labilne w stosunku do kwasów, pochodne diplasmenylo-cholinysprzężone z glikolem polietylenowym (PEG) i zbadano ich wpływ na lipozomy.Opisano szybkość hydrolizy oraz szybkość uwalniania oraz kinetykę tworzenialipozomów DOPE stabilizowanych BVEP stosunków molowych BCEP/DOPE wynoszących1:99, 3:97 oraz 5:95. Zbadano widma 31P NMR, także dla układów z jonami Mn2+dla różnych wartości pH.
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Anion recognition by n,n'-diarylalkanediamides
PublikacjaThe preparation of N,N'-diarylalkanediamides from respective aliphatic dicarboxylic acidesand 4-nitroaniline via microwave-promoted reactions is presented. The most positive effect of microwave irradiation was observed for N,N'-bis(4-nitrophenyl)butanediamide. Anion binding studies on the obtained diamides were carried out in DMSO and acetonitrile using UV-vis and 1H NMR spectroscopy. A mechanism for selective fluoride recognition...
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Toward Polyethylene–Polyester Block and Graft Copolymers with Tunable Polarity
PublikacjaThe synthesis and characterization of polyethylene–polyester block and graft copolymers and their potential as compatibilizers in polyethylene-based polymer blends are being described. The various routes to functionalized polyethylenes and the corresponding block/graft copolymers have been compared and evaluated for their scalability to industrial scale production. Hydroxyl chain-end and randomly OH-functionalized HDPE as well...
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Experimental and theoretical investigation of conformational states and noncovalent interactions in crystalline sulfonamides with a methoxyphenyl moiety
PublikacjaFour sulfonamide derivatives with a methoxyphenyl moiety, namely N-{4-[(2-methoxyphenyl)sulfamoyl] phenyl}acetamide (1a), N-{4-[(3-methoxyphenyl)sulfamoyl]phenyl}acetamide (1b), 4-amino-N-(2- methoxyphenyl)benzenesulfonamide (2a) and 4-amino-N-(3-methoxyphenyl)benzenesulfonamide (2b), have been synthesized and characterized physiochemically by CHNS, MS, FT-IR, 1H NMR, 13C NMR, PXRD and TG methods. Crystal structures were determined...
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The crystal structures of (<i>O</i>-silyl)thiobenzoates (<sup><i>t</i></sup>BuO)<sub>3</sub>SiOC(S)Ph, Ph<sub>3</sub>SiOC(S)Ph, (2,6-XyO)<sub>3</sub>SiOC(S)Ph, and PhC(O)SSSC(O)Ph
PublikacjaChlorek benzylu reaguje z silanotiolanami sodu R3SiSNa dając wyłącznie pochodne sililowe kwasu monotiobenzoesowego R3SiOC(S)Ph, R=t-Bu, Ph lub 2,6-XyO w postaci pomarańczowych kryształów. Wymienione produkty zostały poddane rentgenowskiej analizie strukturalnej. Badania NMR roztworów tych substancji wskazują, że te same izomery są obecne w roztworze i w ciele stałym.
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New class of quaternary ammonium salts, derivatives of methyl D-glucopyranosides.
PublikacjaReakcja zasad azotowych z 6-O-p-tozylo-alfa-D-glukopiranozydem metylu lub 6-O-tozylo-beta-D-glukopiranozydem metylu (prowadzona w skali mikro) dając odpowiednie sole amoniowe. Jako zasady azotowe użyto pirydyny, 2-metylopirydyny i trimetyloaminy. Produkty zostały przebadane przy użyciu spektroskopii 1H, 13C NMR, spektroskopii mas oraz analizy elementarnej a budowa jednego z nich została dodatkowo potwierdzona za pomocą rentgenowskiej...
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The reactivity of 1,1-dichloro-2,2-di-tert-butyldiphosphane towards lithiated metal carbonyls: a new entry to phosphanylphosphinidene dimers
PublikacjaReactions of [Cp*(OC)3M]Li (Cp* = C5Me5, M = Mo, W) towards t-Bu2P–PCl2 lead to the formation of phosphanylphosphinidene dimers [Cp*(OC)3M(η2-t-Bu2P–P)]2 in fairly good yields. The formation of a tetraphosphorus ligand proceeds via reductive dimerization of t-Bu2P–P units. NMR, X-ray investigations and DFT calculations show that the resulting tetraphosphorus ligand has a structure of dication t-Bu2P+=P–P=P+t-Bu2.
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Reactivity of triphosphinoboranes towards H3B·SMe2: access to derivatives of boraphosphacycloalkanes with diverse substituents
PublikacjaTriphosphinoboranes activated the B–H bond in the BH3 molecule without any catalysts at room temperature. Hydroboration reactions led to boraphosphacyloalkanes with diverse structures. The outcomes of reactions depend on the size of the phosphanyl substituent on the boron atom of the parent triphosphinoborane, where derivatives of boraphosphacyclobutane and boraphosphacyclohexane were obtained. Furthermore, the precursor of triphosphinoboranes,...
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Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine
PublikacjaThe process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of ˇ-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes...
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Synthesis, Characterization and Biological Investigations of Half-Sandwich Ruthenium(II) Complexes Containing Benzimidazole Moiety
PublikacjaHalf-sandwich Ru(II) complexes belong to group of biologically active metallo-compounds with promising antimicrobial and anticancer activity. Herein, we report the synthesis and characteri- zation of arene ruthenium complexes containing benzimidazole moiety, namely, [(η6-p-cymene)RuC l(bimCOO)] (1) and [(η6-p-cymene)RuCl2(bim)] (2) (where bimCOO = benzimidazole-2-carboxylate and bim = 1-H-benzimidazole). The compounds were characterized...
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Evaluation of the photoprotective effect of ˇ-cyclodextrin on the emission of volatile degradation products of ranitidine
PublikacjaThe process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of ˇ-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Sam- ples of inclusion complexes...
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Chlorine-free extraction and structural characterization of cellulose nanofibers from waste husk of millet (Pennisetum glaucum)
PublikacjaThis study aims to extract cellulose nanofibers (CNFs) from a sustainable source, i.e. millet husk, which is an agro-waste worthy of consideration. Pre-treatments such as mercerisation, steam explosion, and peroxide bleaching (chlorine-free) were applied for the removal of non-cellulosic components. The bleached millet husk pulp was subjected to acid hydrolysis (5% oxalic acid) followed by homogenization to extract CNFs. The extracted...
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Possible quadrupole-order-driven commensurate-incommensurate phase transition in B20 CoGe
PublikacjaThe B20-type cobalt germanide CoGe was investigated by measuring the specific heat, resistivity, and 59Co nuclear magnetic resonance (NMR).We observed a phase transition at TQ = 13.7 K, evidenced by a very narrow peak of the specific heat and sharp changes of the nuclear spin-spin (T −1 2 ) and spin-lattice (T −1 1 ) relaxation rates. The fact that the entropy release is extremely small and the Knight shift is almost independent...
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Green monoterpenes based deep eutectic solvents for effective BTEX absorption from biogas
PublikacjaThe combustion of biogas which contains significant amounts of monoaromatic hydrocarbons, i.e. benzene, ethylbenzene, toluene, and xylene (BTEX) can cause many technological, environmental, and health problems. Therefore, in these studies, a new physical absorption method based on deep eutectic solvents (DES) consisting of monoterpenes and carboxylic acids was developed for BTEX removal. A total of 39 DES were synthesized, of which...
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Two bacterial small heat shock proteins, IbpA and IbpB, form a functional heterodimer
PublikacjaSmall heat shock proteins (sHsps) are a conserved class of ATP-independent chaperones which in stress conditions bind to unfolded protein substrates and prevent their irreversible aggregation. Substrates trapped in sHsps-containing aggregates are efficiently refolded into native structures by ATP-dependent Hsp70 and Hsp100 chaperones. Most γ-proteobacteria possess a single sHsp (IbpA), while in a subset of Enterobacterales, as...
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Synthesis of some quaternary N-(1,4-anhydro-5-deoxy-D,L-ribitol-5-yl)ammonium salts
PublikacjaOpisano matodę pomyślnego usuwania izopropylidenowych grup ochronnych z 1,4-anhydro-2,3-O-izopropylideno-5-O-tozylo-D,L-rybitolu i czwartorzędowych soli N-(1,4-anhydro-5-deoksy-D,L-rybitolo-5-yl)amoniowych. Struktury otrzymanych związków zostały określone przy pomocy analizy spektralnej, w tym 2D NMR. Otrzymano także dane dyfrakcyjne dla monokryształów 1,4-anhydro-5-O-tozylo-D,L-rybitolu i jego pochodnych 2,3-O-izopropylidenowych.
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Reactions of R2P-P(SiMe3)2 with [(R'3P)2PtCl2]. Syntheses and Structures of [μ2-(1,2:2-η-P2){Pt(PEt3)2}2{Pt(PEt3)2Cl}]+Cl-, [{(Et2PhP)2Pt}2P2], [{(p-Tol3P)2Pt}2P2] and [(p-Tol3P)ClPt(μ-PPh2)2Pt(p-Tol3P)Cl]
PublikacjaReakcje difosfanów R2P-P(SiMe3)2 z [(R'3P)2PtCl2] są bardzo złożone. Główną ścieżką reakcji jest rozszczepienie wiązania P-P w startowym R2P-P(SiMe3)2, po czym następuje utworzenie kompleksu zawierającego P2: [{(R'3P)2Pt}2P2] oraz difosfanu R2P-PR2. Produkty reakcji (zarówno główne jak i uboczne), zostały scharakteryzowane na podstawie spektroskopii 31P NMR. Dla czterech tytułowych związków wykonano rentgenowską analizę strukturalną...
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Syntheses, spectroscopic and structural properties of phenoxysilyl compounds: X-ray structures, FT-IR and DFT calculations
PublikacjaThe reaction of silicon disulfide with alkylphenols leads to tetraphenoxysilane, cyclodisilthiane and silanethiol. The products of the reaction of silicon disulfide with phenols are characterized by FT-IR, NMR, X-ray diffraction and DFT calculations. The intramolecular interactions in the compounds are mainly XH---π (X = C, S) whereas the intermolecular interactions are either very weak CH---π/CH---O contacts found in aryloxysilane...
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The structure, including stereochemistry, of levorin A1
PublikacjaThe constitution and stereostructure of levorin A1 1, an aromatic heptaeneantifungal antibiotic, was established on the basis of NMR studies, which contained DQFCOSY,ROESY, HSQC and HMBC experiments. Mycosamine moiety was used as an internalchiral probe to determine the absolute configuration of levorin A1 stereogenic centers: 13S,15R, 17S, 18R, 19S, 21R. The relative configuration of the remaining stereogenic centers wasassigned...
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Functionalized azobenzocrown ethers as sensor materials—The synthesis and ion binding properties
PublikacjaNew 13- and 16-membered azobenzocrown ethers with aromatic amino, amide, ether–ester or ether–amide residue in para position to an azo moiety were obtained. Acid–base properties and ion binding ability of the colored compounds were studied by spectroscopic methods: UV–vis, fluorimetry and 1H NMR spectroscopy. Selected azobenzocrowns were tested as ionophores in ion-selective membrane electrodes (ISEs) – classic and miniature all...
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Syntheses and structures of the first terminal phosphanylphosphido complexes of molybdenum(IV)
PublikacjaThe reactions of R2P-P(SiMe3)Li (R = tBu, iPr2N) with [Cp2MoCl2] yield terminal phosphanylphosphido complexes formally via the insertion of the phosphinidene P-atom into the C - H bond of a cyclopentadienyl ring and the migration of the hydrogen atom or SiMe3 moiety to the molybdenum centre. Solid state structures of [Cp(C5H4P-PtBu2)MoH], [Cp(C5H4P-PtBu2)Mo(SiMe3)] and [Cp{C5H4P-P(NiPr2)2}Mo(SiMe3)] were established by single crystal...
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A new phosphonium calix[4]arene for selective anion recognition: synthesis and studies in solution and in ion selective electrodes
PublikacjaZaprezentowana została synteza i charakteryzacja tetra (trifenylofosfoniowego) p-tert-butylkaliks[4]arenu 2. Oddziaływania z anionami były badane z użyciem (1)H oraz (31)P NMR i spektrofotometrii absorpcyjnej UV. Badania wykazały oddziaływania z anionami: CLO4-, I-, oraz SCN-. Selektywność jonoforu 2 badano również w membranowych elektrodach jonoselektywnych (ISE) PCV/o-NPOE. Elektroda zawierająca związek 2 generuje odpowiedź potencjometryczną...
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Lower rim substituted tert-butylcalix[4]arenes (II). Complexing ability of5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis-O-(piperidinylcarbonyl)me- thylenecalix[4]arene. The crystal structures of the ligand and its sodium complex
PublikacjaSyntezowano kompleksy wymienionego w tytule liganda z chlorkiem sodu i azotanami itru(III), lantanu(III), samaru(III) i gadolinu(III) w reakcji liganda i odpowiedniej soli, które charakteryzowano za pomocą widm IR, UV-vis,1H NMR, FAB-MS, a także za pomocą analizy elementarnej. W reakcji wymiany z kompleksu z sodem otrzymywano kompleksy z lantanowcami. Określono strukturę krystaliczną wolnego liganda i jego kompleksu z sodem za...
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Silver complexes stabilized by large silanethiolate ligands – crystal structures and luminescence properties
PublikacjaBulky silanethiolate and disiladithiolate ligands were applied to synthesize one mononuclear and three trinuclear silver complexes including two cyclic “microclusters” and a linear tri-nuclear silanethiolate complex. All obtained compounds are characterized by X-ray diffraction and FT-IR. NMR and emission spectroscopies were used where possible. The first trinuclear anionic silver thiolate is structurally characterized. The influence...
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Sulfurization of phosphanylphosphinidene ligand: Access to phosphinothioyltrithiophosphonato platinum(II) complexes
PublikacjaThe reactivity of phosphanylphosphinidene Pt(0) complexes [DppePt(η2-P–PtBu2)] (1) and [(pTol3P)2Pt(η2-P–PtBu2)] (2) toward sulfur was studied. Reactions of 1 and 2 with an excess of sulfur led to the formation of the first transition metal complexes 3 and 4 with phosphinothioyltrithiophosphonato ligands with the formula [tBu2P(=S)–P(=S)S2]2-. In contrast to previous reports on the phosphanylphosphinidene moiety sulfurization,...
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Structure and properties comparison of poly(ether-urethane)s based on nonpetrochemical and petrochemical polyols obtained by solvent free two-step method
PublikacjaThe application of thermoplastic polyurethanes (TPU) is becoming more and more extensive, and the decreasing of used petrochemical monomers and reduction of energy for the polymerization and processing processes is getting increasingly important. In this paper, we confirmed the positive influence of high bio-based monomers contents (by replacing petrochemical polyol and glycol by bio-based counterparts) on processing and properties...
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New Carvone-Based Deep Eutectic Solvents for Siloxanes Capture from Biogas
PublikacjaDuring biogas combustion, siloxanes form deposits of SiO2 on engine components, thus shortening the lifespan of the installation. Therefore, the development of new methods for the purification of biogas is receiving increasing attention. One of the most effective methods is physical absorption with the use of appropriate solvents. According to the principles of green engineering, solvents should be biodegradable, non-toxic, and...
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Reactions of Lithiated Diphosphanes R2P-P(SiMe3)Li (R = tBu, iPr, iPr2N, Et2N) with [Cp2WCl2]. Syntheses and Structures of the First Terminal Phosphanylphosphido Complexes of Tungsten(IV)
PublikacjaReactions of R2P−P(SiMe3)Li (R = tBu, iPr, iPr2N, Et2N) with [Cp2WCl2] yield terminal phosphanylphosphido complexes [Cp(C5H4P-PR2)WH] or [Cp{C5H4P-PR2}-W(SiMe3)] by way of a hydrogen or SiMe3 migration to tungsten. The solid-state structures of [Cp(C5H4P−PtBu2)-WH] and [Cp(C5H4P-PNEt2)WH] were established by singlecrystalX-ray diffraction. Two stereoisomers of [Cp(C5H4P−PtBu2)WH] were identified by solution NMR spectroscopy. Reaction...
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Synthesis of conjugates of muramyl dipeptide and nor-muramyl dipeptide derivatives with adenosine as potential immunosuppressant
PublikacjaZaprezentowano syntezę koniugatów adenozyny z pochodnymi muramylo- i nor-muramylodipeptydów zawierających w części peptydowej D-aminokwasy (D-Ala, D-Val, D-Ser, D-Pro, D-2-ABA). Jako substrat zastosowano rybozyd 6-chloropuryny, który łączono poprzez 1,2-diaminoetan z odpowiednimi pochodnymi MDP lub nor-MDP w obecności EDCI i HOBt. Struktury otrzymanych związków zostały potwierdzone widmami 1H i 13C NMR (500 MHz), widmami MS oraz...
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Synthesis of conjugates of muramyl dipeptide and nor-muramyl dipeptide derivatives with adenosine as potential immunosuppressants
PublikacjaPrzedstawiono syntezę koniugatów pochodnych muramylodipeptydu (MDP) i nor-MDP z adenozyną jako potencjalnych związków o działaniu immunosupresyjnym. Jako substrat zastosowano rybozyd 6-chloropuryny, który łączonp poprzez 1,2-diaminoetan z pochodną MDP lub nor-MDP. Do syntezy wykorzystano pochodne MDP zawierające w części peptydowej D-aminokwasy (D-Ala, D-Val, D-Ser, D-Pro, D-2-ABA). Jako odczynniki sprzęgające zastosowano EDCI...
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Anion binding by p-aminoazobenzene-derived aromatic amides: spectroscopic and electrochemical studies
PublikacjaThe synthesis and complexing properties of p-aminoazobenzene-derived mono-, bis-, and trisamides were described. Ligands 3 and 4 bind anions, including fluorides, chlorides, bromides, acetates, benzoates, dihydrogen phosphates, hydrogen sulfates, and p-toluenesulfonates, in chloroform forming 1 : 1 complexes. The highest value of stability constant was evaluated for the 4-F− complex (log K = 5.63 ± 0.21). On the basis of 1H NMR,...
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Synthesis of analogues of anthraquinones linked to tuftsin or retro-tuftsin residues as potential topoisomerase inhibitors
PublikacjaZsyntetyzowano 10 nowych analogów antrachinonów z pochodnymi tuftsyny i retro-tuftsyny jako potencjalne inhibitory topoizomerazy. Substratem wyjściowym były zsyntetyzowane 1,4-, 1,5- i 1,8-bis(tosyloksy)-9,10-antrachinony oraz odpowiednio chronione pochodne tuftsyny i retro-tuftsyny, które otrzymano metodą mieszanych bezwodników z zastosowaniem chloromrówczanu izobutylu i NMM. Reakcje prowadzone były w acetonitrylu pod azotem w...
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Cation sensing by diphenyl-azobenzocrowns
PublikacjaMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Lower rim substituted p-tert-butylcalix[4]arene; Part 14. Synthesis, structures and binding studies of calix[4]arene thioamides
PublikacjaA number of p-tert-butylcalix[4]arene thioamides were synthesized and characterized by 1H-NMR and elemental analysis. Compounds 1-5 are O-substituted derivatives with -CH2-C(=S)-N-X groups, where NX = morpholidyl, NEt2, NHC2H4Ph, NHCH2Ph and NHEt,respectively. The X-ray structures of the ligands 1, 3, 5 and of the complex 3Pb(ClO4)2, (compound 6), are presented and their slightly distorted cone conformation is established. The...
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Molecular dynamics studies of polyurethane nanocomposite hydrogels
PublikacjaPolyurethane PEO-based hydrogels have a broad range of biomedical applicability. They are attractive for drug-controlled delivery systems, surgical implants and wound healing dressings. In this study, a PEO based polyurethane hydrogels containing Cloisite R 30B, an organically modified clay mineral, was synthesized. Structure of nanocomposite hydrogels was determined using XRD technique. Its molecular dynamics was studied by means...
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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublikacjaThe spectroscopic properties of a series of para-hydroxyazobenzocrowns, including three novel compounds, were investigated using UV–Vis absorption and emission spectroscopy. This study presents, for the first time, determined quantum yield (QY) values for macrocycles of this category, ranging between 0.122 and 0.195. The highest values were obtained for crowns bearing two phenyl substituents in benzene rings. The impact of aromatic...
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Determination of impurities in pharmaceutical products using LC-MS
PublikacjaPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublikacjaThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Ion recognition properties of new pyridine-2,6-dicarboxamide bearing propeller-like pendant residues: multi-spectroscopic approach
PublikacjaThe synthesis and ion binding properties of new amide derived from propeller-like tris(2-pyridyl)amine and 2,6-pyridinedicarboxylic acid chloride were described. Amide binds divalent metal cations: copper(II), nickel(II), zinc(II), and lead(II) in acetonitrile. In acetonitrile:water mixture (9:1 v/v) amide interacts only with copper(II) and nickel(II) cations forming complexes of 1:1 stoichiometry. It was found that the introduction...
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Tri-tert-butoksysilanotiolanowe kompleksy cynku(II), kadmu(II) i kobaltu(II) jako modele koordynacji jonu cynku w miejscu aktywnym dehydrogenazy alkoholowej i niektórych innych enzymów
PublikacjaDehydrogenaza alkoholowa (ADH) katalizuje odwracalne utlenienie alkoholi do aldehydów przy użyciu NAD+ co można podsumować równaniem:R1R2CHOH + NAD+ = R1R2CO + NADH + H+. Geometria koordynacyjna cynku w miejscu aktywnym ADH opisywana jest na ogół jako tetraedryczna jednak istnieją również przesłanki wskazujące na poszerzanie sfery koordynacyjnej metalu w cyklu katalitycznym do LK=5. W pracy przeglądowej opisano badania nad syntetycznymi,...
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N-alkyl derivatives of 2-amino-2-deoxy-D-glucose
PublikacjaMono- i di-N-alkilowe pochodne 1,3,4,6-tetra-O-acetylo-2-amino-2-deoksy-beta-D-glukozy (alkil = metyl, etyl, propyl, butyl, pentyl, heksyl, benzyl) otrzymano w wyniku redukcyjnej alkilacji per-O-acetylo-D-glukozaminy. (N-etylo, N-propylo, N-butylo, N-pentylo, N-heksylo)-1,3,4,6-tetra-O-acetylo-2-amino-2-deoksy-beta-D-glukozy deacetylowano w celu podjęcia prób enzymatycznej fosforylacji. Wszystkie produkty scharakteryzowano za pomocą...
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The products of electro- and photochemical oxidation of 2-hydroxyacridinone, the reference compound of antitumor imidazoacridinone derivatives
PublikacjaBadano reakcje elektrochemicznego utleniania 2-hydroksyakrydonu, związku modelowego aktywnych przeciwnowotworowo pochodnych imidazoakrydonu. Do badań zastosowano metody woltamperometrii cyklicznej, metodę spektroelektrochemiczną oraz elektrolizę przy kontrolowanym potencjale. Badano też reakcje fotochemicznego utleniania. Badania prowadzono w ramach szerszego problemu poznania przemian aktywacji metabolicznej pochodnych hydroksyakrydonu...
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Synthetic Principles Determining Local Organization of Copolyesters Prepared from Lactones and Macrolactones
PublikacjaA highly effective and facile technique for catalytic ring-opening copolymerization (cROP) of lactones viz. ε- caprolactone and ε-decalactone with ω-pentadecalactone is being described. The reactions were mediated by Zn- and Cabased tridentate Schiff base complexes and benzyl alcohol as initiator. The catalysts were successfully employed for the preparation of numerous block and random copolymers. To unravel the composition of...
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Exploring the Reactivity of Unsymmetrical Diphosphanes toward Heterocumulenes: Access to Phosphanyl and Phosphoryl Derivatives of Amides, Imines, and Iminoamides
PublikacjaWe present a comprehensive study on the diphosphanation of iso(thio)cyanates by unsymmetrical diphosphanes. The reactions involving unsymmetrical diphosphanes and phenyl isocyanate or phenyl thioisocyanate gave rise to phosphanyl, phosphoryl, and thiophosphoryl derivatives of amides, imines, and iminoamides. The structures of the diphosphanation products were confirmed through NMR spectroscopy, IR spectroscopy, and single-crystal...
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Quality of limes juices based on the aroma and antioxidant properties
PublikacjaKaffir (Citrus hystrix) and Key (Citrus aurantifolia) limes juices were investigated and compared. Two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF-MS) was applied to assess the botanical origin of Kaffir and Key limes juices, based on volatile substances. The biggest differences in the contents of selected terpenes in Kaffir and Key limes occur in chemical compounds such as Limonene,...
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublikacjaSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Właściwości fizyczne frakcji łoju oraz ich mieszanek
PublikacjaBadano frakcje łoju oraz mieszanki tłuszczowe zawierające te frakcje. W badanych tłuszczach oznaczano zawartość fazy stałej metodą pNMR. Stosowano różne metody termostatowania tłuszczów przed analizą. Wyznaczono również charakterystyki topnienia wybranych tłuszczów, stosując podobne procedury termostatowania jak w przypadku metody NMR. Wydłużenie czasu chłodzenia w temp. 0 st.C wpływało na wzrost zawartości fazy stałej. Im niższa...