Chelate von β-Dicarbonylverbindungen und ihren Derivaten. 48 Ligandeigenschaften von 1-Phenyl-3-methyl-4-thiobenzoylpyrazolon, -4-benzoylthiopyrazolon und -4-benzoylselenopyrazolon

Chelates of β-Dicarbonyl Compounds and their Derivatives. 48. Properties of the 1-Phenyl-3-methyl-4-thiobenzoylpyrazolone, -4-benzoylthiopyrazolone, and -4-benzoylselenopyrazolone Ligands Thio and seleno derivatives of 1-phenyl-3-methyl-4-benzoyl-pyrazolone were synthesized by reaction of 1-phenyl-3-methyl-pyrazolon with dithiobenzoic ester and by reaction of the analogue 4-benzoyl-5-chlorpyrazole with sodium hydrosulfide or -selenide. Metal chelates of Cu, Ni, Co, Zn, Cd, Hg, Tl, and In were isolated. The influence of the central atoms on the optical behaviour was studied.     

Chelate von β-Dicarbonylverbindungen und ihren Derivaten. XVII. Zur Kristallstruktur von Bis-(thioisobutyrylacetonato)-nickel(II)

The x-ray structure analysis of the title Ni^II compound being of the planar coordination type Ni[S₂O₂] gives Ni? S distances of 2.15 Å and Ni? O distances of 1.87 Å. The sulfur atoms are arranged in cis-position. In the chelate ring the C? C distance is shortened in sulfur neighbourhood. This indicates a fixation of the C?C double bonds in the complex.     

Derivate von salicylketonen1: Mitt. schiffsche basen aromatischer o-aminoketone mit ǎthylendiamin und ihre analytische anwendung zur nickelbestimmung

Schiff bases from ethylenediamine with o-aminoacetophenone or o-aminoben-zophenone were prepared, and their chelating properties towards copper, nickel, cobalt, iron, palladium and platinum were studied. The use of the ligands for the photometric determination of metals was tested. A method for the determination of nickel with N,N'-bis(o-aminoacetophenone)-ethylenediimine was developed. Masking agents prevent the interference of iron and copper; a 25-fold amount of palladium and a 10-fold amount of cobalt can be tolerated.     

Tumor necrosis factor α triggers proliferation of adult neural stem cells via IKK/NF-κB signaling

Background  

Brain inflammation has been recognized as a complex phenomenon with numerous related aspects. In addition to the very well-described neurodegenerative effect of inflammation, several studies suggest that inflammatory signals exert a potentially positive influence on neural stem cell proliferation, migration and differentiation. Tumor necrosis factor alpha (TNF-α) is one of the best-characterized mediators of inflammation. To date, conclusions about the action of TNF on neural stem or progenitor cells (NSCs, NPCs) have been conflicting. TNF seems to activate NSC proliferation and to inhibit their differentiation into NPCs. The purpose of the present study was to analyze the molecular signal transduction mechanisms induced by TNF and resulting in NSC proliferation.     

13C-CP/MAS-NMR spectroscopy of tridentate diacidic ligands and their titanium(IV) chelates. molecular structure of bis[benzoylacetone thiobenzoylhydrazonato(2-)]titanium(iv)

A series of tridentate diacidic ligands having the donor set ONO(S) as well as the corresponding titanium(IV) chelates were studied by¹³C-CP/MAS-NMR spectroscopy. Structural changes caused by the complex formation are discussed. The crystal structure of bis[benzoylacetone thiobenzo-ylhydrazonato(2-)]titanium(IV) was determined by X-ray analysis as to be distorted trigonal prismatic. Orthorhombic space group Pca2_l,Z=4, 3304 observed independent reflections, unit-cell parameters at 298 K:a=22,808(2) å,b=13,073(4) å,c=10,450(4) å.     

Flüssig-Flüssig-Extraktion von Vanadium mit ausgewählten zweizähnigen Chelatbildnern

Liquid-Liquid Extraction of Vanadium with Bidentate Ligands The extraction of vanadium(V) as well as vanadium(IV) with thenoyltrifluoracetone, 1-phenyl-3-methyl-4-benzoylpyrazol-5-one, N-benzoyl-N-phenylhydroxylamine, maltol, di-2-ethylhexylphosphoric acid, and selected 8-quinolinols was studied in comparison with corresponding thioanalogue compounds. In the reaction of vanadium(IV) with 7-methyl-8-quinolinol vanadium(IV) and vanadium(V) compounds were isolated side by side.     

Chelate von Chinolin-8-ol-Derivaten. IV [1]

Chelates of 8-Quinolinol Derivatives. IV. Properties, Adduct Formation, and Extraction of Nickel(II) Chelates with n-Alkyl-8-quinolinols Containing Long Chain Substituents The nickel(II) chelates of 5- and 7-nonyl-, 5- and 7-decyl- and 5-chlor-7-decyl-8-quinolinol as well as adducts with water and ammonia were synthesized and characterized by spectra and magnetic moments. The existence of associated forms was concluded. To characterize the influence of substituents the stability and composition of pyridine adducts in solution were determined. Finally the extraction of nickel(II) was studied, and a comparison of extraction data with acid and coordination stability constants was made in the case of the isomeric nonyl-8-quinolinols.     

Synthesis of a chiral amino acid with bicyclo[1.1.1]pentane moiety and its incorporation into linear and cyclic antimicrobial peptides

The synthesis of the lipophilic chiral amino acid 1 bearing the bicyclo[1.1.1]pentane moiety is described. Linear and cyclic hexapeptides of the type Arg-Arg-Xaa-Yaa-Arg-Phe containing 1 instead of one or two tryptophan residues are prepared by solid phase peptide synthesis and the antimicrobial and hemolytic activity of the peptides obtained are discussed.     

The effect of magnetic field on the electrodeposition of CoFe alloys

The superimposition of a homogenous magnetic field during an electrodeposition of CoFe alloy was investigated. A magnetic field superimposed parallel to the electrode surface increases the limiting current density and the deposition rate due to the magnetohydrodynamic (MHD) effect. The deposits obtained in this field configuration appear smoother and more homogenous than the ones obtained without the magnetic field. On the contrary, a magnetic field superimposed perpendicular to the electrode surface does not influence significantly the electrochemical reaction but the morphology of the deposited layers is strongly affected. The roughness is strongly increased in this field configuration and grains grow as separated columns aligned perpendicular to the electrode surface, in the field direction. A magnetic field applied during the deposition affects the magnetic properties of the deposited layers as well. These changes are discussed with respect to the surface roughness and the internal stress state of the layer.