Search results for "deriva"
showing 10 items of 1423 documents
Self-Assembled Molecular Rafts at Liquid|Liquid Interfaces for Four-Electron Oxygen Reduction
2011
The self-assembly of the oppositely charged water-soluble porphyrins, cobalt tetramethylpyridinium porphyrin (CoTMPyP(4+)) and cobalt tetrasulphonatophenyl porphyrin (CoTPPS(4-)), at the interface with an organic solvent to form molecular "rafts", provides an excellent catalyst to perform the interfacial four-electron reduction of oxygen by lipophilic electron donors such as tetrathiafulvalene (TTF). The catalytic activity and selectivity of the self-assembled catalyst toward the four-electron pathway was found to be as good as that of the Pacman type cofacial cobalt porphyrins. The assembly has been characterized by UV-visible spectroscopy, Surface Second Harmonic Generation, and Scanning …
A solvent-free regioselective iodination route of ortho-carboranes.
2006
Tetraiodo-ortho-carborane based X-ray contrast agents can be readily prepared in a high yield, fast, clean, regioselective fashion by a solvent-free reaction of ortho-carboranes with iodine in sealed tubes.
A new simple chromo-fluorogenic probe for NO2 detection in air.
2015
[EN] A new chromo-fluorogenic probe, consisting of a biphenyl derivative containing both a silylbenzyl ether and a N,N-dimethylamino group, for NO2 detection in the gas phase has been developed. A clear colour change from colourless to yellow together with an emission quenching was observed when the probe reacted with NO2. A limit of detection to the naked eye of about 0.1 ppm was determined and the system was successfully applied to the detection of NO2 in realistic atmospheric conditions.
Synthesis, Characterization, and Cu(2+) Coordination Studies of a 3-Hydroxy-4-pyridinone Aza Scorpiand Derivative.
2016
The synthesis, acid-base behavior, and Cu(2+) coordination chemistry of a new ligand (L1) consisting of an azamacrocyclic core appended with a lateral chain containing a 3-hydroxy-2-methyl-4(1H)-pyridinone group have been studied by potentiometry, cyclic voltammetry, and NMR and UV-vis spectroscopy. UV-vis and NMR studies showed that phenolate group was protonated at the highest pH values [log K = 9.72(1)]. Potentiometric studies point out the formation of Cu(2+) complexes of 1:2, 2:2, 4:3, 1:1, and 2:1 Cu(2+)/L1 stoichiometries. UV-vis analysis and electrochemical studies evidence the implication of the pyridinone moieties in the metal coordination of the 1:2 Cu(2+)/L1 complexes. L1 shows …
Crystal structure of the molecular adduct of dimethyltin(IV) chloride with N,N′-ethylenebis(salicylideneiminato) nickel(II)
1974
Abstract N,N′-Ethylenebis(salicylideneiminato)nickel(II) behaves as a neutral bidentate ligand through its oxygen atoms forming binuclear complexes with organotin(IV) chlorides. The crystal structure of the dimethyl derivative is reported.
ChemInform Abstract: Synthesis and anti-Staphylococcal Activity of New Halogenated Pyrroles Related to Pyrrolomycins F.
2008
The chemical synthesis of new halogenated pyrroles related to pyrrolomycins F is described and the anti-staphylococcal activity compared. The replacement of 4′-bromo atom of parent compounds with two chloro atoms at 3′ and 5′ position increase the antibacterial activity against a reference strain of S. aureus.
Crystal structure of hydrocortisone 17-butyrate
2014
In the title compound, C25H36O6, the two central cyclohexane rings exhibit a chair conformation. The terminal cyclohexene and cyclopentane rings are in half-chair and envelope conformations (with the C atom bearing the methyl substituent as the flap), respectively. The methyl group of the butyrate chain is disordered over two orientations, with a refined occupancy ratio of 0.742 (6):0.258 (6). Intramolecular O—H...O and C—H...O hydrogen bonds are observed. In the crystal, molecules are linked by O—H...O hydrogen bonds into chains running parallel to theaaxis.
LEGAL CONSIDERATIONS REGARDING THE INTRODUCTION AND IMPLEMENT OF THE PROPOSED `FINANCIAL TRANSACTION TAX` ON PENSION FUNDS. IMPACT ON TRANSACTION COS…
2012
In economies in which pension obligations are substantial, it is important that there is a high degree of trust in the financial reporting of pensions by employers and by pension plans. The objective of this paper is to assess legal considerations regarding the introduction and implement of financial transaction tax mechanisms in private pension system. In line with this objective, an understanding of causes, implications, solutions for pensions is essential to being able to efficiently and effectively create a secure fiscal environment.
Rapid self-healing and anion selectivity in metallosupramolecular gels assisted by fluorine-fluorine interactions.
2017
Simple ML2 [M = Fe(II), Co(II), Ni(II)] complexes obtained from a perfluoroalkylamide derivative of 4-aminophenyl-2,2′,6,2′-terpyridine spontaneously, yet anion selectively, self-assemble into gels, which manifest an unprecedented rapid gel strength recovery, viz. self-healing, and thermal rearrangement in aqueous dimethyl sulfoxide. The key factor for gelation and rheological properties emerges from the fluorine–fluorine interactions between the perfluorinated chains, as the corresponding hydrocarbon derivative did not form metallogels. The perfluoro-terpyridine ligand alone formed single crystals, while its Fe(II), Co(II) or Ni(II) complexes underwent rapid gelation leading to highly enta…