Search results for " radical"

showing 10 items of 757 documents

The effect of chlorine substituent(s) on the primary loss of a methyl radical from chlorinated veratroles (1,2-dimethoxybenzenes)

1989

chemistry.chemical_compoundPrimary (chemistry)ChemistryMass spectrumMolecular MedicineMethyl radicalPhotochemistryChlorine substituentInstrumentationBiochemistrySpectroscopyElectron ionizationOrganic Mass Spectrometry
researchProduct

Versuche zum Vorgang der Wasserstoffübertragung, XI. Isomerisierung Definiert Deuterierter Alkylbenzole an Raney-Nickel

1964

α-Deutero-toluol. o-, m- und p-Deutero-toluol sowie β-Deutero-athylbenzol isomerisieren schon bei 20° in Beruhrung mit wasserfreiem Raney-Nickel. Der Deuterium-Gehalt des Substrates bleibt dabei annahernd konstant. Beim α-Deutero-toluol wandern mehr als 50% des Deuteriums aus der Seitenkette in den Kern, wobei es sich weitgehend auf die gleichen Positionen verteilt wie beim Austausch von leichtem Toluol mit Deuterium-Gas an Raney-Nickel. Der aromatische Kern wird unter diesen Bedingungen nicht abgesattigt. Mit Hilfe der Massenspektrographie kann gezeigt werden, das Deuterium auch zwischenmolekular ausgetauscht wird. — Im Toluol kernstandiges Deuterium verteilt sich an Raney-Nickel auf samtl…

chemistry.chemical_compoundchemistryOrganic ChemistryAlkyl radicalsPhysical and Theoretical ChemistryTolueneMedicinal chemistryJustus Liebigs Annalen der Chemie
researchProduct

[39] DNA damage induced by ultraviolet and visible light and its wavelength dependence

2000

Publisher Summary DNA damage induced by solar radiation in mammalian cells consists largely of two types of modification: pyrimidine dimers and oxidative modifications. Pyrimidine dimmers that can be subdivided into cyclobutane pyrimidine dimmers, (CPDs) and (6-4) photoproducts are the characteristic and most abundant modifications after direct excitation of DNA, although they can also be formed indirectly by energy transfer from other excited molecules such as carbonyl compounds. Oxidative DNA damage, which includes various pyrimidine and purine modifications, sites of base loss (AP sites), and strand breaks, is generated in only low yield after direct excitation of DNA (except at very sho…

chemistry.chemical_compoundchemistryPyrimidineSinglet oxygenDNA damagemedicinePyrimidine dimerFree radical damage to DNAmedicine.disease_causePhotochemistryDNAUltravioletCyclobutane
researchProduct

Hydroxyl Radical Addition to Thymine and Cytosine and Photochemistry of the Adducts at the C6 Position

2019

chemistry.chemical_compoundchemistryRadicalOrganic ChemistryHydroxyl radicalPhysical and Theoretical ChemistryPhotochemistryCytosineAnalytical ChemistryAdductThymineChemPhotoChem
researchProduct

Modellazione eco-idrologica del ruolo delle radici nell'analisi di stabilità di un versante

2014

coesione radicaleSettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaModellistica eco-idrologica
researchProduct

Inappropriabilità, improprietà, produzione. Il comune, un'introduzione

2021

Si tratta di una ricostruzione del modo in cui il concetto di "comune" è stato usato nel pensiero radicale degli ultimi anni. The essay reconstructs the way in wich the concept of common has been used in radical thinking in recent years.

concept of common radical thinking
researchProduct

Increased conformational rigidity of humic substances by oxidative biomimetic catalysis

2005

A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe(TDCPPS)Cl, was employed as a biomimetic catalyst in the oxidative coupling of terrestrial humic materials. High-performance size-exclusion chromatography (HPSEC), solid-state nuclear magnetic resonance (CPMAS-(13)C NMR), electron paramagnetic resonance (EPR), and diffuse reflectance infrared spectroscopy (DRIFT) were used to follow conformational and structural changes brought about in different humic materials by the oxidative coupling. Increase in apparent weight-average molecular weight (Mw(a)) occurred invariably for all humic substances with the oxidative polymerization catalyzed …

conformationMagnetic Resonance SpectroscopySpectrophotometry InfraredPolymers and PlasticsDiffuse reflectance infrared spectroscopy (DRIFT)Biomimetic materialsaromatic compoundgel permeation chromatographyMolecular ConformationPhotochemistryIron compoundslaw.inventionPolymerizationenvironmental managementcovalent bondlawSize exclusion chromatographyBiomimetic catalysisBiomimeticsMaterials ChemistryOrganic chemistryHumic acidElectron paramagnetic resonanceInfrared spectroscopyChromatography High Pressure Liquidchemistry.chemical_classificationSettore CHIM/03 - Chimica Generale e InorganicaCarbon IsotopesChromatographyindustryCatalystsChemistrytetra(2articleelectrophoretic mobilitybiomimetic materialNuclear magnetic resonance spectroscopyunclassified drugConformationsacetic acidpriority journalCovalent bondSpectrophotometrySynthesis (chemical)High Pressure Liquidtechnology6 dichloro 3 sulfonatophenyl)porphyrinic acid derivativeInfraredOxidation-Reductionmolecular stabilityHumic materialsoxidationSettore AGR/13 - Chimica AgrariaSupramolecular chemistryBioengineeringcomplex mixturesCatalysisCatalysisdiffuse reflectance spectroscopyhumic substanceBiomaterialsalkyl etherElectron spin resonance spectroscopycomplex formationParticle SizeNuclear magnetic resonance spectroscopyHumic Substancesfree radicalbiomimetic oxidative humicelectron spin resonanceHigh performance size exclusion chromatography (HPSEC)ferrous chloridemolecular weightsolid statecarbon nuclear magnetic resonancePolymerizationSolubilitychemical structureOxidative coupling of methaneCatalysts; Conformations; Electron spin resonance spectroscopy; Infrared spectroscopy; Iron compounds; Nuclear magnetic resonance spectroscopy; Oxidation; Polymerization; Size exclusion chromatography; Solubility; Synthesis (chemical); Biomimetic catalysis; Diffuse reflectance infrared spectroscopy (DRIFT); High performance size exclusion chromatography (HPSEC); Humic materials; Biomimetic materials; acetic acid; alkyl ether; aromatic compound; biomimetic material; ferrous chloride; free radical; tetra(26 dichloro 3 sulfonatophenyl)porphyrinic acid derivative; unclassified drug; article; carbon nuclear magnetic resonance; catalysis; catalyst; chemical structure; complex formation; conformation; covalent bond; diffuse reflectance spectroscopy; electron spin resonance; electrophoretic mobility; environmental management; gel permeation chromatography; humic substance; industry; molecular stability; molecular weight; oxidation; polymerization; priority journal; solid state; technology; Biomimetics; Carbon Isotopes; Catalysis; Chromatography High Pressure Liquid; Electron Spin Resonance Spectroscopy; Humic Substances; Magnetic Resonance Spectroscopy; Molecular Conformation; Oxidation-Reduction; Particle Size; Spectrophotometry Infraredcatalyst
researchProduct

Synthesis of 3-alkyl-4-(cholomethyl)-1-RSO2-1-H-pyrrol-2-(5H)ones, using a sequential ATCR/[1,2] elimination, from 2,2-dichloro-N-(2-chloroallyl)-N-R…

2011

copper cyclization elimination lactams radical reactionSettore CHIM/06 - Chimica Organica
researchProduct

Gas phase behavior of radical cations of perfluoroalkyl-1,2,4-triazines: an experimental and theoretical study

2009

Electron ionization mass spectrometry and low-energy collision-induced decomposition reactions occurring in a tridimensional ion trap, together with density functional theory (DFT) calculations on neutrals, even- and odd-electron cations, have been used to study the gas-phase ion chemistry of a series of perfluoroalkyl-1,2,4-triazines. Loss of oxygen, due to thermal degradation occurring before ionization, likely involving the hydroxylamino group, has been observed. Compounds having a carbonyl group at position 6 of the triazine ring fragment in the source by elimination of NO followed by HF or CO. The decomposition pathways occurring due to CID experiments have shown interesting features d…

electron ionizationFree RadicalsStereochemistryIonic bondingDFT calculationAntineoplastic AgentsMass spectrometryGas Chromatography-Mass SpectrometryIonradical ionTandem Mass SpectrometryComputational chemistrySpectroscopyElectron ionizationFluorocarbonsMolecular StructureTriazinesChemistryPolyatomic ionSettore CHIM/06 - Chimica OrganicaModels ChemicalRadical ionUnpaired electronDensity functional theorytriazineGasesfluorinated compounds
researchProduct

The Importance of Electronic Dimensionality in Multiorbital Radical Conductors

2019

The exceptional performance of oxobenzene-bridged bis-1,2,3-dithiazolyls 6 as single-component neutral radical conductors arises from the presence of a low-lying π-lowest unoccupied molecular orbital, which reduces the potential barrier to charge transport and increases the kinetic stabilization energy of the metallic state. As part of ongoing efforts to modify the solid-state structures and transport properties of these so-called multiorbital materials, we report the preparation and characterization of the acetoxy, methoxy, and thiomethyl derivatives 6 (R = OAc, OMe, SMe). The crystal structures are based on ribbonlike arrays of radicals laced together by S···N′ and S···O′ secondary bondin…

electronic dimensionalitymultiorbital radical conductorsvapaat radikaalitkiteetsähkönjohtavuus
researchProduct