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showing 10 items of 7178 documents

Die copolymerisation des acroleins mit einigen vinylmonomeren. Polymere acroleine. 9. Mitt.

1958

Die Copolymerisation des Acroleins in wasrigem Medium wird untersucht und die copolymerisationsparameter folgender Systeme bestimmt: Acrolein/Aacrylnitril (r1 = 1,09; r2 = 0,77); Acrolein/Acrylamid (r1 = 2,0; r2 = 0,76); Acrolein/Acrylsauremethylester (r1 = 0,2; r2 = 10,0) und Acrolein/Vinylacetat (r1 = 3,3; r2 = 0,1). Ferner werden die Qund e-Werte fur Acrolein berechet und sein Verhalten bei der Copolymerisation diskutiert. The copolymerisation of acrolein in aqueous medium has been investigated and the reactivity ratios of the following systems were determined: acrolein/acrylonitrile (r1 = 1.09; r2 = 0.77 ); acrolein/acrylamide (r1 = 2.0; r2 = 0.76); acrolein/methacrylate (r1 = 0.2; r2 =…

chemistry.chemical_compoundAqueous mediumchemistryAcrylamidePolymer chemistryAcroleinOrganic chemistryReactivity (chemistry)AcrylonitrileMethacrylateDie Makromolekulare Chemie
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Pharmakologisch aktive polymere, 5. Modellreaktionen zur umsetzung von pharmaka und enzymen mit monomeren und polymeren reaktiven estern

1973

Die Darstellung reaktiver Ester der Acryl-, Methacryl- und N-Vinylcarbaminsaure wird beschrieben. Die Verbindungen sind im Gegensatz zu anderen reaktiven Saurederivaten wie Saurechloriden, -anhydriden und Isocyanaten kristalline Monomere, die gut zu handhaben sind. Sie lassen sich leicht zu unvernetzten, loslichen Polymeren homo- und copolymerisieren. Die Copolymerisationsparameter wurden bestimmt. Entsprechend wie die aus der Peptidchemie bekannten reaktiven Ester reagieren sie in monomerer wie in polymerer Form bei niedriger Temperatur selektiv und schonend mit Nucleophilen in guten Ausbeuten, z. B. mit Aminen in wasriger Losung. Dies eroffnet die Moglichkeit zur nebenreaktionsfreien Bind…

chemistry.chemical_compoundAqueous solutionMonomerNucleophilechemistryPolymer chemistryCopolymerPeptide chemistryReactivity (chemistry)macromolecular substancesDie Makromolekulare Chemie
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Photocatalytic oxidation of acetonitrile in aqueous suspension of titanium dioxide irradiated by sunlight

2004

The photocatalytic oxidation of acetonitrile (CH3CN) was carried out in aqueous suspensions of polycrystalline TiO2 P25 Degussa irradiated by sunlight. A plug flow photoreactor in a total recycle loop was used for carrying out reactivity experiments in which the concentrations of acetonitrile, of its intermediate oxidation products and of not-purgeable organic carbon (NPOC) were monitored. The influence of the presence of strong oxidant species (H2O2, S2O82−, ClO−) on the process rate was studied. The dependence of acetonitrile photo-oxidation rate on the substrate concentration and on the catalyst amount was also investigated. The photodegradation rate of substrate and NPOC followed first …

chemistry.chemical_compoundAqueous solutionchemistryTitanium dioxideInorganic chemistryPhotocatalysisSubstrate (chemistry)Reactivity (chemistry)PhotodegradationAcetonitrileGeneral Environmental ScienceCatalysisAdvances in Environmental Research
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New multicomponent catalysts for the selective aerobic oxidative condensation of benzylamine to N-benzylidenebenzylamine

2014

Aerobic oxidative condensation of benzylamine to N-benzylidenebenzylamine was carried out on new gold-based catalysts using as support bimodal UVM-7-like mesoporous silica containing Ni and Ce (or Sn) as oxide nanodomains partially embedded inside the mesoporous UVM-7 silica walls. These nanodomains acted as effective and stable inorganic anchors favoring the nucleation, growth and stability of supported gold particles. Following the atrane method (a “one-pot” strategy able to harmonize the hydrolytic reactivity of different heteroelements through the use of complexes containing triethanolamine-derived ligands (atranes) as precursors) the stability of the oxide nanodomains during oxidation …

chemistry.chemical_compoundAtranechemistryChemical engineeringOxideNanoparticleOrganic chemistryReactivity (chemistry)Mesoporous silicaSelectivityMesoporous materialCatalysisCatalysisCatal. Sci. Technol.
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Effect of Monooxygenase Inducers on the Binding of Benzo-(A)Pyrene Metabolites to Cellular Macromolecules in Perfused Rat Lungs

1978

The irreversible binding of metabolically activated [3H]-benzo(a)pyrene (BP) to cellular macromolecules of isolated perfused rat lungs was studied. Lungs from differently pretreated animals were perfused in situ in a recirculating system without ventilation. BP with a specific activity of 10 mCi/μmol was added to 50 ml perfusion medium containing 40% washed bovine erythrocytes to a final concentration of 1 μM. DNA, RNA and protein fractions were isolated and assayed for irreversibly bound radioactivity.

chemistry.chemical_compoundBenzo(a)pyrenechemistryBiochemistryRNAPyreneInducerSpecific activityMonooxygenaseDNAMacromolecule
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5,6,7-Trimethoxy-2,3-dihydro-1H,8H-benzo[a]pyrrolo[3,4-c]carbazole-1,3-dione dimethyl sulfoxide solvate

2005

The crystal structure of the title compound, C21H16N2O5·C2H6OS, was determined to investigate the electrocyclic reactivity of 3,4-di­aryl-1H-pyrrole-2,5-diones (3,4-bisarylmal­eimides) to the yield corresponding carbazole derivatives.

chemistry.chemical_compoundChemistryCarbazoleYield (chemistry)Organic chemistryGeneral Materials ScienceSulfoxideReactivity (chemistry)General ChemistryCrystal structureCondensed Matter PhysicsActa Crystallographica Section E Structure Reports Online
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Macromolecules with groups of high reactivity

1960

Reactions on the reactive groups of macromolecular substances (e.g., cellulose) have long been known, even since before the structures of macromolecules were understood. H. Staudinger carried out numerous reactions with macromolecules, maintaining the degree of polymerization constant, in order to substantiate the macromolecular structure of the substances investigated (polymeric-analogous reactions). During the last fifteen years reactions with macromolecules have been investigated because it was desirable to compare the chemical diversity of low molecular weight compounds with the corresponding chemical diversity of macromolecular compounds. These endeavors bring forth materials which sup…

chemistry.chemical_compoundChemistryChemical diversityMacromolecular SubstancesOrganic chemistryReactivity (chemistry)Degree of polymerizationCelluloseMacromolecular CompoundsMacromoleculeGroup 2 organometallic chemistryJournal of Polymer Science
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Antimykotische Wirkstoffe, 16. Mitt. Halogenierte Cyanaminomethylenpiperidine und -piperazine

1984

Die in Gegenwart der sekundaren Amine 5a-e mit Hilfe von s-Triazin (2) als Dreikomponentenreaktion durchgefuhrte Aminomethinylierung von Cyanamid (1) liefert die korrespondierenden als Dehydro-N-Mannich-Basen aufzufassenden Cyanaminomethylenheterocyclen 6a-e. Insbesondere 6a und 6e besitzen antimykotische Wirksamkeit. Antimycotic Agents, XVI: Halogenated (Cyanaminomethylene)piperidines and -piperazines The aminomethinylation of cyanamide (1) by means of s-triazine (2), carried out as three-component reaction in the presence of the secondary amines 5a–e, yields the cyanaminomethylene heterocycles 6a–e, which are to be classed as dehydro-N-Mannich bases. Compounds 6a and 6e in particular show…

chemistry.chemical_compoundChemistryDrug DiscoveryPharmaceutical ScienceOrganic chemistryAmine gas treatingCyanamideBiological activityMannich baseArchiv der Pharmazie
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Heterocyclic rearrangements. Phenylhydrazones andN-methyl-N-phenylhydrazones of 3-acylisoxazoles

1983

The reaction of 3-benzoyl-5-phenylisoxazole (4) and 3-acetyl-5-methylisoxazole (5) with phenylhydrazine and N-methyl-N-phenylhydrazine has been investigated and the reactivity of (E)- and (Z)-phenylhydrazones and N-methyl-N-phenylhydrazones has been studied.

chemistry.chemical_compoundChemistryOrganic ChemistryTriazole derivativesReactivity (chemistry)Medicinal chemistryPhenylhydrazineJournal of Heterocyclic Chemistry
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ChemInform Abstract: Highly Enantio- and Diastereoselective Inverse Electron Demand Hetero-Diels-Alder Reaction Using 2-Alkenoylpyridine N-Oxides as …

2009

A general catalytic inverse electron demand hetero-Diels Alder reaction for 2-alkenoylpyridine N-oxides is presented. 2-Alkenoylpyridine N-oxides react very efficiently with alkenes in the presence of bisoxazolidine-copper(II) [BOX-Cu(II)] complexes to give chiral dihydropyrans bearing a pyridine ring at the 6-position with very high yields and excellent diastereo- and enantioselectivity. These heterodienes exhibited higher reactivity and enantioselectivity than the corresponding non-oxidized 2-alkenoylpyridines.

chemistry.chemical_compoundChemistryPyridineInverseReactivity (chemistry)General MedicineElectronRing (chemistry)Medicinal chemistryCatalysisDiels–Alder reactionChemInform
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