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Search results for: synthetic benchmarking
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Developments in the synthesis and biological activity of Glycyl-L-Histydyl-L-Lysine derivatives
PublicationWe emphasize on the methods of the synthesis described in the literature and present the aspects of Gly-His-Lys structure modifications that played a key role in scientific research.
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Synthesis and characterisation of polyurethane elastomers with semi-products obtained from polyurethane recycling
PublicationIn this work polyurethane elastomers were synthesised by using different mixtures of a petrochemical and glycerolysate polyols and 4,4-diphenylmethane diisocyanate (MDI). Glycerolysate polyol was produced from polyurethane foam decomposition using crude glycerine as a decomposition agent. The structure and thermal properties of obtained semi-product were similar to the polyol used in the synthesis of original foam. Glycerolysate...
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Synthesis and properties of AxV2Al20 (A = Th, U, Np, Pu) ternary actinide aluminides
PublicationPolycrystalline samples of AxV2Al20 (A = Ce, Th, U, Np, Pu; 0.7 ≤ x ≤ 1.0) actinide intermetallics were synthesized using the arc-melting method. Crystal structure studies were performed by means of powder x-ray diffraction and the Rietveld refinement method. All studied compounds crystallize in the CeCr2Al20-type structure (space group Fd-3m, no. 227) with the actinoid and Ce atom located in the oversized icosahedral cage formed...
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Synthesis and steroid sulfatase inhibitory activities of N-alkanoyl tyramine phosphates and thiophosphates
PublicationA series of phosphate and thiophosphate analogs based on the frameworks of N-alkanoyl tyramines have been synthesized and biologically evaluated. Their binding modes have been modeled using docking techniques. The inhibitory effects of the synthesized compounds were tested on STS isolated from the human placenta as well as the MCF-7, MDA-MB-231 and SkBr3 cancer cell lines. Most of the new STS inhibitors possessed potent activity...
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Hydrothermal reactions: From the synthesis of ligand to new lanthanide 3D-coordination polymers
PublicationThe organic ligand 2,5-piperazinedione-1,4-diaceticacid (H2PDA) was synthesized under hydrothermal conditions starting from the iminodiacetic acid and catalyzed by oxalic acid. The X-ray powder diffraction data indicates that the compound crystallizes in the P21/c space group as reported in the literature. The ligand was also characterized by elemental analysis, magnetic nuclear resonance, infrared spectroscopy and thermogravimetric...
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Rearrangement of azoxybenzocrowns into chromophoric hydroxyazobenzocrowns and the use of hydroxyazobenzocrowns for the synthesis of ionophoric biscrown compounds
PublicationThe Wallach rearrangement was used as a method for preparing p-hydroxyazobenzocrown ethers starting from different azoxybenzocrowns as substrates. Synthesis of a series of p-hydroxyazobenzocrowns under modified conditions and characterization of the obtained products are presented. o-Hydroxyazobenzocrowns were identified among the products of the photochemical rearrangement of azoxybenzocrowns. Novel biscrowns were synthesized...
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Synthesis and application of tetrazole di and triamide derivatives in ion-selective membrane electrodes
PublicationA number of tetrazole diamides and triamides have been synthesized and applied as ion carries in ion-selective membrane electrodes. Their selectivity and sensitivity were studied towards alkali, alkaline earth, transition and heavy metal cations. it was found that membranes doped with 3 and 2-nitrophenyl octyl ether exhibit an almost theoretial Nernstian response for NH+ over relatively wide concentration range. Elestrodes with...
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Synthesis, spectroscopy and computational studies of some novelphosphorylated derivatives of quinoline-5,8-diones
PublicationThe neutral phosphorus nucleophiles such as R2P(=Y)M allowed the radical addition to 2-methyl-5,8-dioxo-5,8-dihydroquinoline-7-amine and N-(2-methyl-5,8-dioxo-5,8-dihydroquinolin-7-yl)acetamide giving exclusively O-phosphorylated products. All products were quantitatively prepared and characterized by microanalysis, and multinuclear NMR spectroscopy. Seven of them, have been characterized by single crystal X-ray diffraction method....
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Anion recognition by phosphonium calix[4]arens: synthesis and physico-chemical studies
Publicationp-tert-butylcalix[4]arenes in the cone conformation, di-and tetra substituted at the narrow rim with charged phosphonium groups have been synthesies and characterised.
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
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Comparison of Optimization Techniques for Coupling Matrix Synthesis Using Eigenvalue Based Approach
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Synthesis of 5-Substituted 1H-Tetrazoles from Nitriles in the Presence of Heterogeneous Catalyst
PublicationTetrazoles are five-membered heterocyclic compounds containing in their rings four nitrogen atoms. They have wide applications as corrosion inhibitors, analytical reagents, high-energy materials and gas generating compositions. Tetrazoles also play important role in coordination chemistry as ligands and in medicinal chemistry as metabolically stable surrogates for carboxylic acids. In recent years, investigation of new method of...
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A Green Chemistry "environmentally friendly" approach to the synthesis of chloro-intermediates of ephedrine/pseudoephedrine
PublicationMethylamphetamine is an addictive stimulant drug that strongly activates certain systems in the brain. It is closely related chemically to amphetamine, but the central nervous system effects of methamphetamine are greater. There is much interest in methylamphetamine among scientists and therefore the synthesizes of methylamphetamine and its metabolites are carried out on a large scale in chemical laboratories. Globally, ephedrine...
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Solid-phase synthesis and characterization of N-acetylated Gly-His-Lys analogues
PublicationZaprezentowano nowe analogi tripeptydu Gly-His-Lys (GHK), stanowiącego sekwencję naturalnie występującą w -II-łańuchu kolagenu, skąd jest uwalniany w stanach zapalnych i w procesach gojenia się ran. Gly-His-Lys jest szeroko stosowany na rynku kosmetycznym w połączeniu z kwasem palmitynowym, który ułatwia jego wnikanie w głąb skóry. Zaplanowane modyfikacje zawierały fragment Gly-X-Y (X=Met, Hyp, Hyp-Met, Gly-Hyp; Y=Lys, D-Lys) i...
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Application of Syntactic Pattern Recognition Approach in Design and Optimisation of Group Machining Systems
PublicationRozwinięto koncepcję budowy zoptymalizowanych struktur systemów wytwarzania grupowego spektrum części z wykorzystaniem modelu analizy syntaktycznej sekwencji operacji ich procesów technologicznych. Określono formułę metryki odległościowej opisu stopnia zróżnicowania marszrut indywidualnych procesów oraz testowano jej skuteczność w aspekcie eksploracji wielowymiarowych danych i klasteryzacji obiektów wg cech wymagań technologicznych....
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Synthesis, spectroscopy and computational studies of some biologically important hydroxyhaloquinolines and their novel derivatives
PublicationA series crystalline compounds of methyl and phosphinyl derivatives of 2-methylquinolin-8-ol (1a) and related 5,7-dichloro-2-methylquinolin-8-ol (1b) were quantitatively prepared and characterized by microanalysis, IR, UV-vis and multinuclear NMR spectroscopy. Five of them have been characterized by single crystal X-ray diffraction method. The known compounds, 8-methoxy-2-methylquinoline (2a) and 8-methoxyquinoline (2d), were synthesised...
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Catalysts for advanced oxidation processes: Deep eutectic solvents-assisted synthesis – A review
PublicationNew catalyst synthesis techniques, including green materials, are extensively studied for heterogeneous photocatalytic advanced oxidation processes (AOPs) on spotlight of sustainable development. Deep eutectic solvents (DESs) started to be used in this field as environmentally friendly alternative to ionic liquids (ILs). During the catalyst synthesis, DESs can act as stabilizers, capping agents, structure directing agents, templates,...
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Efficient synthesis of N-benzyloxycarbonyl- and N-tert-butoxycarbonyl-(S)-isoserine and their derivatives
PublicationOpisano wydajną metodę syntezy N-benzyloksykarbonylo- i N-tert-butoksykarbo-nylo-(S)-izoseryny i jej pochodnych z kwasu L-jabłkowego poprzez odpowiednie oksazolidinony i hydrolizę tych połączeń za pomocą wodorotlenku benzylowo-trimetyloamoniowego.
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Inhibitors of glucosamine-6-phosphate synthase as potential antimicrobials or antidiabetics – synthesis and properties
PublicationGlucosamine-6-phosphate synthase (GlcN-6-P synthase) is known as a promising target for antimicrobial agents and antidiabetics. Several compounds of natural or synthetic origin have been identified as inhibitors of this enzyme. This set comprises highly selective L-glutamine, amino sugar phosphate or transition state intermediate cis-enolamine analogues. Relatively low antimicrobial activity of these inhibitors, poorly penetrating...
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Computer-assisted pronunciation training—Speech synthesis is almost all you need
PublicationThe research community has long studied computer-assisted pronunciation training (CAPT) methods in non-native speech. Researchers focused on studying various model architectures, such as Bayesian networks and deep learning methods, as well as on the analysis of different representations of the speech signal. Despite significant progress in recent years, existing CAPT methods are not able to detect pronunciation errors with high...
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Shape-controllable synthesis of GdVO4 photocatalysts and their tunable properties in photocatalytic hydrogen generation
PublicationNovel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light...
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Beta-Galactosidases of Pseudoalteromonas sp. – Characteristics and application for lactose hydrolysis and galactopyranosides synthesis
PublicationBeta-galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It has biotechnological applications in the dairy industry for the production of milk with a low content of lactose and galactooligosacharides for use in healthy food. The transgalactosylation activity of beta-galactosidase can be used in the synthesis of alkyl galactopyranosides. Due to the fact that conditions of...
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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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The new diphosphanylphosphido complexes of tungsten(VI) and molybdenum(VI). Their synthesis, structures and properties
PublicationWe report on the reactivity of R2P–P(Li)–PR’2 (R = tBu, iPr, R’ = NEt2, iPr) towards diimido complexes [(dippN)2MCl2·dme] (M = Mo, W and dipp = 2,6-iPr2C6H3). A series of new complexes with diphosphanylphosphido ligands R2P–P–PR’2 were isolated. The solid-state structures of [(dippN)2M(Cl)(1,2-η-iPr2P–P– PiPr2)] (2Mo and 2W) and [(dippN)2M(Cl){1,2-η-tBu2P–P–P(NEt2)2}] (3Mo and 3W) were established by single-crystal X-ray diffraction...
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Voiceless Stop Consonant Modelling and Synthesis Framework Based on MISO Dynamic System
PublicationA voiceless stop consonant phoneme modelling and synthesis framework based on a phoneme modelling in low-frequency range and high-frequency range separately is proposed. The phoneme signal is decomposed into the sums of simpler basic components and described as the output of a linear multiple-input and single-output (MISO) system. The impulse response of each channel is a third order quasi-polynomial. Using this framework, the...
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Synthesis and properties of HoT2Al20 (T = Ti, V, Cr) intermetallic cage compounds
PublicationPolycrystalline samples of HoT2Al20 (T = Ti, V, Cr) intermetallics were synthesized using a step-wise arc-melting technique. All three compounds adopt the CeCr2Al20-type crystal structure with Ho atoms positioned inside oversized icosahedral cages formed by Al atoms. The structure of HoV2Al20 compound is reported. The materials properties were studied by means of electrical resistivity, magnetic susceptibility, and specific heat...
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Comprehensive study on graphene hydrogels and aerogels synthesis and their ability of gold nanoparticles adsorption
PublicationGraphene hydrogels were prepared by ascorbic acid-assisted gelation of graphene oxide (GO) aqueous suspensions both in acidic and basic conditions. Different mass ratio of ascorbic acid (AA) to GO was used (namely 20:1 and 10:1). In order to eliminate the influence of AA on the final structure of hydrogels, samples without AA were prepared by a hydrothermal gelation of GO in an autoclave. An in-depth structural characterization...
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A new approach to the stereoselective synthesis of trans-3-carbamoyl-b-lactam moieties†
PublicationOne-pot synthesis of optically active 1,4-disubstituted-3-carbamoyl-azetidinones from 5-[(N-arylamino)- (hydroxyl)methylene]-2,2-dimethyl-1,3-dioxa-4,6-diones and chiral aldimines is achieved via thermal generation of carbamoyl ketenes and subsequent [2+2] cycloaddition. Three possible chiral induction approaches were tested and (R)-(+)-1-phenylethylamine was confirmed as the best chiral auxiliary. Among the four possible diastereoisomers,...
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Synthesis of bimetallic Co–Pt/cellulose nanocomposites for catalytic reduction of p-nitrophenol
PublicationIn this study, bimetallic nanoparticles (NPs) of Co–Pt anchored on cellulose nanofibers (CNFs) for catalytic applications were synthesized via a sonochemical approach. The electro-spinning technique was employed for the synthesis of CNFs from cellulose acetate. The thorough characterization of synthesised Co–Pt/CNF nanocomposites was performed with the help of scanning electron microscopy (SEM), Fourier transform infra-red (FT-IR)...
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Ladder-Based Synthesis and Design of Low-Frequency Buffer-Based CMOS Filters
PublicationBuffer-based CMOS filters are maximally simplified circuits containing as few transistors as possible. Their applications, among others, include nano to micro watt biomedical sensors that process physiological signals of frequencies from 0.01 Hz to about 3 kHz. The order of a buffer-based filter is not greater than two. Hence, to obtain higher-order filters, a cascade of second-order filters is constructed. In this paper, a more...
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SYNTHESIS OF PHOSPHORUS TACRINE ANALOGUES AS A NEW POTENTIAL ANTI-ALZHEIMER’S DISEASE AGENTS
PublicationA series of novel phosphorus tacrine derivatives was obtained in three steps, including synthesis of 9-chlorotacrine, connection of 9-chlorotacrine with hexamethylenediamine, 1,8-diaminooctane and 1,12-diaminododecane linkers and reaction of obtained tacrine diamine analogues with corresponding acid ester to give nine tacrine organophosphorus compounds. All of the obtained final structures were characterized by 1H NMR, 13C NMR,...
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Diastereoselective Synthesis of Z‐Alkenyl Disulfides from α‐Thiophosphorylated Ketones and Thiosulfonates
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical Z‐alkenyl disulfides under mild conditions in moderate to good yields. The designed method is based on the reaction of α‐thiophosphorylated carbonyl compounds with thiotosylates in the presence of a base. The developed method allows the preparation of unsymmetrical Z‐alkenyl disulfides bearing additional hydroxy, carboxy, or ester functionalities
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A New Approach to Chemical Recycling of Polyamide 6.6 and Synthesis of Polyurethanes with Recovered Intermediates
PublicationA new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino- glycolysis process. The described process of decomposition did not...
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New synthesis route of highly porous InxCo4Sb12 with strongly reduced thermal conductivity
PublicationHighly porous, In-filled CoSb3 skutterudite materials with an attractive thermoelectric figure of merit (ZT * 1) and corresponding dense samples were fabricated through the cost-effective method of reduction in oxides in dry hydrogen and the pulsed electric current sintering (PECS) method, respectively. The reduction process was described in detail using in situ thermogravimetric analysis of Co2O3, Sb2O3 and In(NO3)35H2O separately...
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Rational design, synthesis and biological evaluation of thiadiazinoacridines: a new class of antitumor agents.
PublicationZsyntetyzowano serię związków o potencjalnej zdolności do wiązania się z DNA z grupy tiadiazinoakrydyn poprzez cyklizację odpowiednich pochodnych 9-imino-4-nitro-9,10-dihydroakrydyny. Zbadano ich zdolność do wiązania się z DNA oraz cytotoksyczność względem kilku linii komórek nowotworwych. Badania aktywności przeciwnowotworowej wobec białaczki P388 wskazały na zgodność tych wyników z wynikami cytotoksyczności in vitro. Wykazano,...
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Synthesis and ionophoric properties of functionalized p-tert-butyl-calix[4]arenes
PublicationProjektowanie struktury związków o właściwościach jonoforowych stanowi ważny element chemii supramolekularnej. W pracy przedstawiono wyniki badań nad funkcjonalizacją makrocyklicznych kaliks[4]arenów prowadzacą do nowych związków o zróżnicowanych właściwościach kompleksujących. Syntezowane przez nas jonofory badane były w membranowych elektrodach jonoselektywnych. Wyznaczono potencjometryczne współczynniki selektywności oraz stałe...
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A convenient synthesis of (S)-O-benzyl-N-tert-butoxycarbonyl-beta-tyrosine.
PublicationOpracowano dogodną metodę syntezy tytułowego aminokwasu z aldehydu 4-benzyloksybenzoesowego, kwasu malonowego i octanu amonu. Otrzymany aminokwasu rozdzielono na enancjomery poprzez krystalizację soli diastereoizomerycznej z kwasem L-winowym.
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The synthesis of 1,4,7,10-tetraazacyclododecanes with acetylsalicylic side arm as potential cobalt(II) fluorophores.
PublicationMonoacylowe pochodne 1,4,7,10-tetraazacyklododekanu otrzymano w bezpośredniej reakcji cyklenu z chlorkiem kwasu salicylowego, jak również przy użyciu trichronionego cyklenu. Monoacylową pochodną wykorzystano następnie w reakcji z fosforynem etylu otrzymując difunkcyjny związek. Otrzymane ligandy zbadano spektrofotometrycznie. Obydwa ligandy oddziaływują selektywnie z jonami Co(II), tworząc kompleksy o stechiometrii 2:1 i 1:1 (ligand:metal).
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Investigation of the Effects of Primary Structure Modifications within the RRE Motif on the Conformation of Synthetic Bovine Herpesvirus 1‐Encoded UL49.5 Protein Fragments
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The influence of a synthetic growth hormone‐releasing hormone analogue G11 and opioid peptide biphalin on selected fibroblasts parameters relevant to wound healing
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Reversed-phase and normal-phase thin-layer chromatography and their application to the lipophilicity prediction of synthetic pyrethroids based on quantitative structure–retention relationships
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Analogues of trypsin inhibitor SFTI-1 modified in the conserved P1′ position by synthetic or non-proteinogenic amino acids retain their inhibitory activity
PublicationA series of linear and monocyclic (with a disulfide bridge only) analogues of trypsin inhibitor SFTI-1 modified in the P-1 and/or P-1' positions were synthesized by the solid-phase method. In the substrate specificity P-1 position, Phe or N-benzylglycine (Nphe) were introduced, whereas the conserved Ser6 in Bownam-Birk (BBI) inhibitors was replaced by Hse (L-homoserine), Nhse [N-(2-hydroxyethyl)glycine], Sar, and Ala. Kinetic studies...
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Synthesis of Bis(ethylenedithio)dithiadiazafulvalenes (BEDT-DTDAF) and Generation of Charge Transfer Complexes with Tetracyanoquinodimetane
PublicationW artykule opisana została synteza Bis(etylenoditio)ditiadiazafulwalenów (BEDT-DTDAF) wykorzystująca jako kluczowe związki przejściowe 4,5-(etylenoditio)tiazol oraz sole 3-aliklo-4,5-(etylenoditio)tiazoliowe oraz generowanie przewodzących kompleksów z przeniesieniem ładunku usyskanych z Bis(etylenoditio)ditiadiazafulwalenów oraz tetracyjanochinodimetanu.
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Stimulated by cyclodextrins high yield synthesis of azocrown analogues comprising pyrrole or imidazole residues
PublicationBadano wpływ cyklodekstryn na reakcję syntezy aza-eterów zawierających w strukturze pirol lub imidazol. Stosowano alfa-, beta- i gamma-cyklodekstryny. Uzyskane wyniki analizowano pod kątem sposobu umieszczenia cząsteczki azolu we wnęce cyklodekstryny.
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Synthesis of new conjugates of MDP and nor-MDP with retro-tuftsin derivatives as potential immunomodulators
PublicationZsyntetyzowano nowe analogi muramylodipeptydu (MDP) i nor-muramylo-dipeptydu (nor-MDP) z pochodnymi retro-tuftsyny jako potencjalne immunomodulatory. Przedstawiono także syntezę odpowiednich pochodnych retro-tuftsyny. Do syntezy wykorzystano metodę mieszanych bezwodników z chloromrówczanem izobutylu i N-metylomorfoliną w bezwodnym DMF.
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Synthesis of analogues of anthraquinones linked to tuftsin or retro-tuftsin residues as potential topoisomerase inhibitors
PublicationZsyntetyzowano 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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Synthesis, single crystal growth and properties of Sr 5 Pb 3 ZnO 12
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Synthesis, Growth Mechanism, and Electrochemical Properties of Hollow Mesoporous Carbon Spheres with Controlled Diameter
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Synthesis, characterization and growth mechanism of mesoporous hollow carbon nanospheres by catalytic carbonization of polystyrene
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Selective Synthesis of Magnetite Nanospheres with Controllable Morphologies on CNTs and Application to Lithium‐Ion Batteries
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