Refine
Year of publication
- 2014 (187) (remove)
Document Type
- Article (127)
- Postprint (32)
- Doctoral Thesis (13)
- Review (6)
- Preprint (4)
- Habilitation Thesis (2)
- Other (2)
- Conference Proceeding (1)
Is part of the Bibliography
- yes (187) (remove)
Keywords
- anomalous diffusion (5)
- living cells (5)
- arsenolipids present (4)
- cod-liver (4)
- fatty-acids (4)
- identification (4)
- physiological consequences (4)
- visible-light (4)
- infection pathway (3)
- ionic liquids (3)
- models (3)
- polyzwitterion (3)
- synthesis (3)
- Anisotropy effect (2)
- Arenesulfonamides (2)
- Aromaticity (2)
- Chelatoaromaticity (2)
- Cycloaddition (2)
- DNA origami (2)
- DNA radiation damage (2)
- Fokker-Planck equations (2)
- G quadruplexes (2)
- Janus emulsions (2)
- RP-HPLC (2)
- TiO2 nanoparticles (2)
- Trifluoromethanesulfonamide (2)
- X-ray (2)
- absorbtion fine-structure (2)
- acinar-cells (2)
- atomic force microscopy (2)
- attachment (2)
- augmented-wave method (2)
- betaine (2)
- biomaterials (2)
- biomineralization (2)
- bladder-cancer (2)
- brownian-motion (2)
- carbohydrates (2)
- carcinogen exposure (2)
- cellulose (2)
- chemoradiation therapy (2)
- chromoionophore (2)
- cockroach salivary-glands (2)
- construction (2)
- cytosine methylation (2)
- damage (2)
- diimine-complexes (2)
- dna coiling (2)
- drugs (2)
- dynamics (2)
- electron-transfer (2)
- enzyme reactions (2)
- excision-repair (2)
- excitation (2)
- excluded volume (2)
- fish (2)
- flight search patterns (2)
- fluctuation-dissipation theorem (2)
- fluorescence (2)
- fluorescence photobleaching recovery (2)
- folding kinetics (2)
- fractional dynamics approach (2)
- frameworks (2)
- gas-phase (2)
- gene-expression (2)
- gene-regulation kinetics (2)
- genomic dna methylation (2)
- graphite (2)
- green (2)
- hela-cells (2)
- human-cells (2)
- hybrid materials (2)
- hydrogen (2)
- in-vitro (2)
- indicators (2)
- induced malignant-transformation (2)
- initio molecular-dynamics (2)
- intermittent chaotic systems (2)
- intracellular na+ (2)
- ion optodes (2)
- ionische Flüssigkeiten (2)
- ionophore (2)
- langevin equation (2)
- levy flights (2)
- lifetime microscopy (2)
- low-energy electrons (2)
- marine oils (2)
- mass-spectrometry (2)
- membrane (2)
- membranes (2)
- metabolites (2)
- metathesis (2)
- methyltransferases dnmt3a (2)
- microporous organic polymers (2)
- mixtures (2)
- molecular rods (2)
- molecular-mechanisms (2)
- monomer (2)
- nanoclusters (2)
- nanoparticles (2)
- oil (2)
- oxidation (2)
- periplaneta-americana (2)
- photon-counting statistics (2)
- photooxidation (2)
- polyampholyte (2)
- polymer (2)
- polymerization (2)
- post-polymerization modification (2)
- protein binding (2)
- quantum dots (2)
- random-walks (2)
- rat (2)
- reactivity (2)
- reduction (2)
- resonant formation (2)
- review (2)
- rp-hplc (2)
- ruthenium (2)
- samples (2)
- sensors (2)
- simulations (2)
- single-molecule analysis (2)
- single-particle tracking (2)
- single-strand breaks (2)
- sodium green (2)
- sorption (2)
- spatial-organization (2)
- supported gold (2)
- surface (2)
- switches (2)
- systems (2)
- tandem reaction (2)
- thio-dimethylarsinic acid (2)
- tight-binding (2)
- time random-walks (2)
- transition (2)
- trivalent (2)
- ventricular myocytes (2)
- vitro toxicological characterization (2)
- water (2)
- weak ergodicity breaking (2)
- zwitterionic group (2)
- (+)-Tephrodin (1)
- (Anti)aromaticity (1)
- 1,1-dimethyl-1,2,3,4-tetrahydrosiline (1)
- 1,3-Dienes (1)
- 1,5-Dienes (1)
- 3,4-dihydro-2H-pyran (1)
- 3,4-dihydro-2H-thiopyran (1)
- 3,6-Diazabicyclo[3.1.0]hexanes (1)
- 3,8-Diazabicyclo[3.2.1]octane (1)
- 3-Oxo-14 alpha, 15 alpha-epoxyschizozygine (1)
- 3D electrode structures (1)
- 4,4-dimethyl-3,4-dihydro-2H-1,4-thiasiline (1)
- 6 alpha-Hydroxy-alpha-toxicarol (1)
- Acetylpolyamine amidohydrolases (1)
- Adsorbent (1)
- Adsorption kinetic (1)
- Alkin (1)
- Allylic oxidation (1)
- Alternating polyampholytes (1)
- Antibody (1)
- Antimicrobial activities (1)
- Aromatic or quinonoid (1)
- Azid (1)
- Base pairing (1)
- Batterien (1)
- Binding assay (1)
- Binding pocket position (1)
- Biomineralisation (1)
- Biphenol (1)
- Block copolymers (1)
- Bulbine frutescens (1)
- C-13 (1)
- C-13 chemical shift difference Delta delta(C C) (1)
- Carbene ligands (1)
- Carbohydrates (1)
- Cassiamin A (1)
- Cassiamin B (1)
- Chemotaxonomy (1)
- Chromanon (1)
- Chromon (1)
- Clay-polymer nanocomposite - CPN (1)
- Click chemistry (1)
- Conformational equilibrium (1)
- Copper Metal Complexes (1)
- Copper(II) (1)
- Cross coupling (1)
- Cryo-SEM (1)
- Crystal structure (1)
- Cumarin (1)
- Cyclic GMP (1)
- Cytotoxicity (1)
- DLS (1)
- Dependent light scattering (1)
- Desorption (1)
- Diastereomers assignment (1)
- Dielectric properties (1)
- Dimensionsstabilität (1)
- Dimeric anthraquinone (1)
- Diterpenoid (1)
- Dodonaea angustifolia (1)
- Dynamic NMR (1)
- ESI-MS (1)
- ESR (1)
- Emulsification (1)
- Emulsion destabilization (1)
- Energiespeicher (1)
- Escherichia coli (1)
- F-19 (1)
- FLNS (1)
- Fabry-Perot etalon (1)
- Farbstoff (1)
- Flavanone (1)
- Flavone (1)
- Fluorescence (1)
- Fluorescence life time (1)
- Fluorescent nanoconjugate (1)
- Fluoreszens (1)
- GC-MS (1)
- H-1 (1)
- Hapten (1)
- Hard sphere model in the Percus-Yevick Approximation (1)
- Hemiporphyrazines (1)
- High-cell-density culture (1)
- High-resolution spectrometer (1)
- Histone deacetylases (1)
- Holzmodifikation (1)
- Homogeneous catalysis (1)
- Imidazolium (1)
- Interfacial equilibrium (1)
- Interfacial tension (1)
- Ionic Liquid (1)
- Ionic liquids (1)
- Isolations (1)
- Janus drops (1)
- Klick (1)
- Kohlenstoff (1)
- LCST (1)
- LIBS (1)
- Langmuir layers (1)
- Laser-induced breakdown spectroscopy (1)
- Lithium-Schwefel-Batterien (1)
- Magnetic properties (1)
- Magnetit Nanopartikel (1)
- Maltose-modified PEI (1)
- Mammea usambarensis (1)
- Mammea-type coumarins (1)
- Mars (1)
- Mechanical properties (1)
- Metallcarbide (1)
- Metallnitride (1)
- Metathesis (1)
- Methane (1)
- Methanogens (1)
- Michael addition (1)
- Microfluidics (1)
- Microorganism (1)
- Microparticles Reagentless assay (1)
- Micropolarity (1)
- Micropollutants (1)
- Microviscosity (1)
- Millettia dura; (1)
- Millettia leucantha (1)
- Millettia oblata ssp teitensis (1)
- Miniaturized cultivations (1)
- Molecular Probe (1)
- Monte-Carlo simulations (1)
- Multiple light scattering (1)
- Muonic molecules (1)
- N-azobenzylchitosan (1)
- N-methylnicotinamide (1)
- NMR (1)
- Nanosensor (1)
- Nanostrukturen (1)
- Naphthyridines (1)
- Network structure (1)
- Nicotinamide (1)
- Occupation quotient pi*/pi (1)
- Oligospiroketal (1)
- Optical oxygen sensor (1)
- Oxygen heterocycles (1)
- PQQ-GDH (1)
- Palladium (1)
- Paratope (1)
- Phenol (1)
- Phenylanthraquinone (1)
- Phospholipids (1)
- Plasmid DNA production (1)
- Plasmodium falciparum (1)
- Platelet (1)
- Platinum group metals (1)
- Polarization elements (1)
- Polycyclic aromatic hydrocarbons (1)
- Polymer (1)
- Polymer dispersions (1)
- Polymerized ionic liquids (1)
- Polypeptide (1)
- Polystyrene-divinylbenzene (1)
- Porphyrins (1)
- Pseudomonas aeruginosa (1)
- Push-pull alkynes (1)
- Push-pull effect (1)
- Quantum Chemical Calculations (1)
- Quantum dots (1)
- Radicals (1)
- Radikalrekombination (1)
- Raman spectroscopy (1)
- Ring-current effect (1)
- Ruthenium (1)
- Schizozygane indoline alkaloid (1)
- Schizozygia coffaeoides (1)
- SnAr reaction (1)
- Sol-Gel (1)
- Solid-phase extraction (1)
- Spin probes (1)
- Spinning drop (1)
- Stab (1)
- Stereochemistry (1)
- Steric hindrance (1)
- Structural investigations (1)
- Structure revision (1)
- Sub-zero temperature (Celsius) (1)
- Sulphoxide (1)
- Superkondensatoren (1)
- Supramolecular compounds (1)
- Surface exudates (1)
- Template phase (1)
- Tephrosia purpurea (1)
- Tephrosia villosa (1)
- Tetraoxo[8]circulenes (1)
- Tetraphenylethene Bioassay Fluorescent dye (1)
- Theoretical calculations (1)
- Thermal behavior (1)
- Thermoresponsive (1)
- Thiol-X (1)
- Through-space NMR shielding (TSNMRS) (1)
- ToF-SIMS (1)
- Wacker reaction (1)
- Wassergehalt (1)
- Water treatment (1)
- Wavelength modulation spectroscopy (laser spectroscopy) (1)
- Xanthone (1)
- Yukawa model in the Mean Spherical Approximation (1)
- Zwitterionen (1)
- absorption (1)
- acceptors (1)
- adduct formation (1)
- adenoassociated virus (1)
- adhesives (1)
- adsorption (1)
- alkine (1)
- amphiphilic polymer assembly (1)
- anti-polyelectrolyte effect (1)
- articulated (1)
- azide (1)
- azobenzenes (1)
- battery (1)
- bioanalysis (1)
- bioelectrochemistry (1)
- biosensor (1)
- biphenol (1)
- block copolymers (1)
- brewster angle microscopy (1)
- calcium phosphate (1)
- carbon (1)
- carotenoids (1)
- cations (1)
- cell-death (1)
- chitosan (1)
- chlorophyll (1)
- chromanone (1)
- chromone (1)
- click (1)
- click chemistry (1)
- composites (1)
- conductive polymer (1)
- confocal raman microscopy (1)
- contrast agents (1)
- copolymers (1)
- coumarine (1)
- crosslinking (1)
- crystal structures (1)
- cyclization (1)
- cytoplasm (1)
- cytosolic sodium (1)
- de novo synthesis (1)
- degradation (1)
- density functional calculations (1)
- diffractive elements (1)
- dimensional stability (1)
- direct bioelectrocatalysis (1)
- dye (1)
- dyes/pigments (1)
- electrically switchable gratings. (1)
- electrolytes (1)
- ellipsometry (1)
- emulsion microscopy (1)
- endosomal escape (1)
- energy storage (1)
- energy transfer (1)
- epsilon-caprolactone (1)
- escence correlation spectroscopy (1)
- escherichia-coli (1)
- europium (1)
- europium complex (1)
- excimer UV light (1)
- exposure (1)
- extraction (1)
- fluorescence correlation spectroscopy (1)
- fluorescence label (1)
- fluoroimmunoassay (1)
- food contact material (1)
- free radical polymerization (1)
- freie radikalische Polymerisation (1)
- graphene oxide (1)
- grazing incidence X-ray diffraction (1)
- green chemistry (1)
- hemocompatibility (1)
- heterocycles (1)
- hydrophobe Moleküle (1)
- hydrophobic molecules (1)
- hydrothermal (1)
- imidazole (1)
- imidazolium (1)
- intracellular-transport (1)
- ion exchange (1)
- ionic liquid (1)
- isomerization (1)
- isotope effect (1)
- kinetic models (1)
- labels (1)
- lactate (1)
- lanthanide luminescence (1)
- laser-enhanced nuclear fusion (1)
- lichtinduziert (1)
- light induced (1)
- lipid monolayer (1)
- lithium sulfur battery (1)
- macroITO (1)
- magnetite (1)
- magnetosome (1)
- magnetotactic bacteria (1)
- magnetotaktische Bakterien (1)
- manganese (1)
- mechanical-properties (1)
- mesoporous materials (1)
- metal carbides (1)
- metal coordination (1)
- metal nitrides (1)
- methylmercury (1)
- microemulsions (1)
- moisture content (1)
- molecular dynamics simulations (1)
- morphology (1)
- nachhaltige Chemie (1)
- nachwachsende Rohstoffe (1)
- nano clay (1)
- nanobioconjugate (1)
- nanoparticle (1)
- nanostructures (1)
- nematic phase (1)
- neurodegenerative diseases (1)
- neurotoxicity (1)
- onformational analysis (1)
- phenol (1)
- photochemistry (1)
- photochromism (1)
- photoinduced radical polymerization (1)
- photoswitches (1)
- pi-pi stacking (1)
- platelet aging (1)
- platelet function (1)
- platelet rich plasma (1)
- platelet storage (1)
- platform chemicals (1)
- polarization gratings (1)
- poly(ADP-ribose) polymerase-1 (1)
- poly(epsilon-caprolactone) methacrylate (1)
- polyelectrolyte adsorption (1)
- polyesterurethane (1)
- polyesterurethanes (1)
- polymer micelles (1)
- polymer/LC composites (1)
- radical recombination (1)
- rearrangement (1)
- relaxation NMR spectroscopy (1)
- renewables (1)
- repair (1)
- resonance energy-transfer (1)
- restricted N-S rotation (1)
- ring-opening polymerization (1)
- rod (1)
- sacrificial bonds (1)
- seco-Anthraquinone (1)
- self-assembly (1)
- self-healing materials (1)
- shape-memory effect (1)
- side reaction (1)
- sol-gel (1)
- sol-gel processes (1)
- stannous octoate (1)
- statistical copolymer (1)
- structural-characterization (1)
- substituent effects (1)
- sulfobetaine (1)
- super-intense laser pulses (1)
- supercapacitors (1)
- surface charge (1)
- surface chemistry (1)
- switchable retarder (1)
- system (1)
- thermoresponsive materials (1)
- thimerosal (1)
- time-resolved fluorescence (1)
- trafficking (1)
- two-dimensional phases (1)
- upper critical solution temperature (1)
- visible light (1)
- whole blood (1)
- wood modification (1)
- xanthophylls (1)
- zinc (1)
Institute
- Institut für Chemie (187) (remove)
Phytochemical investigation of the dichloromethane/methanol (1:1) extract of the roots of Bulbine frutescens led to the isolation of a new xanthone, 8-hydroxy-6-methylxanthone-1-carboxylic acid (1) and a new phenylanthraquinone, 6',8-O-dimethylknipholone (2) along with six known compounds. The structures were elucidated on the basis of NMR and MS spectral data analyses. The structure of compound 1 was confirmed through X-ray crystallography which was then used as a reference to propose the revision of the structures of six seco-anthraquinones into xanthones. The isolated compounds were evaluated for cytotoxicity against human cervix carcinoma KB-3-1 cells with the phenylanthraquinone knipholone being the most active (IC50 = 0.43 mu M). Two semi-synthetic knipholone derivatives, knipholone Mannich base and knipholone-1,3-oxazine, were prepared and tested for cytotoxic activity; both showed moderate activities (IC50 value of 1.89 and 2.50 mu M, respectively). (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.
The stem bark extract of Schizozygia coffaeoides (Apocynaceae) showed moderate antiplasmodial activity (IC50 = 8-12 mu g/mL) against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Chromatographic separation of the extract led to the isolation of a new schizozygane indoline alkaloid, named 3-oxo-14 alpha, 15 alpha-epoxyschizozygine. In addition, two dimeric anthraquinones, cassiamin A and cassiamin B, were identified for the first time in the family Apocynaceae. The structures of the isolated compounds were deduced on the basis of spectroscopic evidence. The schizozygane indole alkaloids showed good to moderate antiplasmodial activities (IC50 = 13-52 mu m). (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.
The new N-heterocyclic carbene (NHC) complex [PdCl2{(CN)(2)IMes}(PPh3)] (2) ({(CN)(2)IMes}: 4,5-dicyano-1,3-dimesitylimidazol-2-ylidene) and the NHC palladacycle [PdCl(dmba){(CN)(2)IMes}] (3) (dmba: N,N-dimethylbenzylamine) have been synthesized by thermolysis of 4,5-dicyano-1,3-dimesityl-2-(pentafluorophenyl) imidazoline (1) in the presence of suitable palladium(II) precursors. The acyclic complex 2 was formed by ligand exchange using the mononuclear precursor [PdCl2(PPh3)(2)] and the palladacycle 3 was formed by cleavage of the dinuclear chloro-bridged precursor [Pd(mu-Cl)(dmba)](2). The new NHC precursor 1-benzyl-4,5-dicyano-2-(pentafluorophenyl)-3-picolylimidazoline (5) was formed by condensation of pentafluorobenzaldehyde with N-benzyl-N'-picolyldiaminomaleonitrile (4). The NHC palladacycle [PdCl2{(CN)(2)IBzPic}] (6) ({(CN)(2)IBzPic}: 1-benzyl-4,5-dicyano-3-picolylimidazol-2-ylidene) was prepared by in situ thermolysis of 5 in the presence of [PdCl2(PhCN)(2)]. The three palladium(II) complexes were characterized by NMR and IR spectroscopy, mass spectrometry and elemental analysis. In addition, the molecular structures of 2 and 3 were determined by X-ray diffraction. The pi-acidity of (CN)(2)IBzPic was compared with (CN)(2)IMes and perviously reported pi-acidic imidazol-2-ylidenes by NBO analysis. The Mizoroki-Heck (MH) reactions of various aryl halides with n-butyl acrylate were performed in the presence of complexes 2, 3 and 6. The new precatalysts showed high activity in the MH reactions giving good-to-excellent product yields with 0.1 mol-% pre-catalyst. The nature of the catalytically active species of 2, 3 and 6 was investigated by poisoning experiments with mercury and transmission electron microscopy. It was found that palladium nanoparticles formed from the precatalysts were involved in the catalytic process.
DNA origami nanostructures allow for the arrangement of different functionalities such as proteins, specific DNA structures, nanoparticles, and various chemical modifications with unprecedented precision. The arranged functional entities can be visualized by atomic force microscopy (AFM) which enables the study of molecular processes at a single-molecular level. Examples comprise the investigation of chemical reactions, electron-induced bond breaking, enzymatic binding and cleavage events, and conformational transitions in DNA. In this paper, we provide an overview of the advances achieved in the field of single-molecule investigations by applying atomic force microscopy to functionalized DNA origami substrates.
DNA origami nanostructures allow for the arrangement of different functionalities such as proteins, specific DNA structures, nanoparticles, and various chemical modifications with unprecedented precision. The arranged functional entities can be visualized by atomic force microscopy (AFM) which enables the study of molecular processes at a single-molecular level. Examples comprise the investigation of chemical reactions, electron-induced bond breaking, enzymatic binding and cleavage events, and conformational transitions in DNA. In this paper, we provide an overview of the advances achieved in the field of single-molecule investigations by applying atomic force microscopy to functionalized DNA origami substrates.
On the role of fluoro-substituted nucleosides in DNA radiosensitization for tumor radiation therapy
(2014)
Gemcitabine (2′,2′-difluorocytidine) is a well-known radiosensitizer routinely applied in concomitant chemoradiotherapy. During irradiation of biological media with high-energy radiation secondary low-energy (<10 eV) electrons are produced that can directly induce chemical bond breakage in DNA by dissociative electron attachment (DEA). Here, we investigate and compare DEA to the three molecules 2′-deoxycytidine, 2′-deoxy-5-fluorocytidine, and gemcitabine. Fluorination at specific molecular sites, i.e., nucleobase or sugar moiety, is found to control electron attachment and subsequent dissociation pathways. The presence of two fluorine atoms at the sugar ring results in more efficient electron attachment to the sugar moiety and subsequent bond cleavage. For the formation of the dehydrogenated nucleobase anion, we obtain an enhancement factor of 2.8 upon fluorination of the sugar, whereas the enhancement factor is 5.5 when the nucleobase is fluorinated. The observed fragmentation reactions suggest enhanced DNA strand breakage induced by secondary electrons when gemcitabine is incorporated into DNA.
On the role of fluoro-substituted nucleosides in DNA radiosensitization for tumor radiation therapy
(2014)
Gemcitabine (2′,2′-difluorocytidine) is a well-known radiosensitizer routinely applied in concomitant chemoradiotherapy. During irradiation of biological media with high-energy radiation secondary low-energy (<10 eV) electrons are produced that can directly induce chemical bond breakage in DNA by dissociative electron attachment (DEA). Here, we investigate and compare DEA to the three molecules 2′-deoxycytidine, 2′-deoxy-5-fluorocytidine, and gemcitabine. Fluorination at specific molecular sites, i.e., nucleobase or sugar moiety, is found to control electron attachment and subsequent dissociation pathways. The presence of two fluorine atoms at the sugar ring results in more efficient electron attachment to the sugar moiety and subsequent bond cleavage. For the formation of the dehydrogenated nucleobase anion, we obtain an enhancement factor of 2.8 upon fluorination of the sugar, whereas the enhancement factor is 5.5 when the nucleobase is fluorinated. The observed fragmentation reactions suggest enhanced DNA strand breakage induced by secondary electrons when gemcitabine is incorporated into DNA.
The quantum dynamics of muonic molecular ions dd mu and dt mu excited by linearly polarized along the molecular (z)-axis super-intense laser pulses is studied beyond the Born-Oppenheimer approximation by the numerical solution of the time-dependent Schrodinger equation within a three-dimensional model, including the internuclear distance R and muon coordinates z and rho. The peak-intensity of the super-intense laser pulses used in our simulations is I-0 = 3.51 x 10(22) W/cm(2) and the wavelength is lambda(l) = 5nm. In both dd mu and dt mu, expectation values < z > and <rho > of muon demonstrate "post-laser-pulse" oscillations after the ends of the laser pulses. In dd mu post-laser-pulse z-oscillations appear as shaped nonoverlapping "echo-pulses". In dt mu post-laser-pulse muonic z-oscillations appear as comparatively slow large-amplitude oscillations modulated with small-amplitude pulsations. The post-laser-pulse rho-oscillations in both dd mu and dt mu appear, for the most part, as overlapping "echo-pulses". The post-laser-pulse oscillations do not occur if the Born-Oppenheimer approximation is employed. Power spectra generated due to muonic motion along both optically active z and optically passive rho degrees of freedom are calculated. The fusion probability in dt mu can be increased by more than 11 times by making use of three sequential super-intense laser pulses. The energy released from the dt fusion in dt mu can by more than 20 GeV exceed the energy required to produce a usable muon and the energy of the laser pulses used to enhance the fusion. The possibility of power production from the laser-enhanced muon-catalyzed fusion is discussed.