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Redox activation

Palacin S, Lesieur P, Stefanelli I and Barraud A 1988 Structural studies of intermolecular interactions in pure and diluted films of a redox-active phthalocyanine Thin Soiid Fiims 159 83-90... [Pg.2633]

A substantial fraction of the named enzymes are oxido-reductases, responsible for shuttling electrons along metabolic pathways that reduce carbon dioxide to sugar (in the case of plants), or reduce oxygen to water (in the case of mammals). The oxido-reductases that drive these processes involve a small set of redox active cofactors , that is, small chemical groups that gain or lose electrons. These cofactors include iron porjDhyrins, iron-sulfur clusters and copper complexes as well as organic species that are ET active. [Pg.2974]

Olefin synthesis starts usually from carbonyl compounds and carbanions with relatively electropositive, redox-active substituents mostly containing phosphorus, sulfur, or silicon. The carbanions add to the carbonyl group and the oxy anion attacks the oxidizable atom Y in-tramolecularly. The oxide Y—O" is then eliminated and a new C—C bond is formed. Such reactions take place because the formation of a Y—0 bond is thermodynamically favored and because Y is able to expand its coordination sphere and to raise its oxidation number. [Pg.28]

Two efficient syntheses of strained cyclophanes indicate the synthetic potential of allyl or benzyl sulfide intermediates, in which the combined nucleophilicity and redox activity of the sulfur atom can be used. The dibenzylic sulfides from xylylene dihalides and -dithiols can be methylated with dimethoxycarbenium tetrafiuoroborate (H. Meerwein, 1960 R.F. Borch, 1968, 1969 from trimethyl orthoformate and BFj, 3 4). The sulfonium salts are deprotonated and rearrange to methyl sulfides (Stevens rearrangement). Repeated methylation and Hofmann elimination yields double bonds (R.H. Mitchell, 1974). [Pg.38]

The thioredoxin domain (see Figure 2.7) has a central (3 sheet surrounded by a helices. The active part of the molecule is a Pa(3 unit comprising p strands 2 and 3 joined by a helix 2. The redox-active disulfide bridge is at the amino end of this a helix and is formed by a Cys-X-X-Cys motif where X is any residue in DsbA, in thioredoxin, and in other members of this family of redox-active proteins. The a-helical domain of DsbA is positioned so that this disulfide bridge is at the center of a relatively extensive hydrophobic protein surface. Since disulfide bonds in proteins are usually buried in a hydrophobic environment, this hydrophobic surface in DsbA could provide an interaction area for exposed hydrophobic patches on partially folded protein substrates. [Pg.97]

R. T. Boere and T. L. Roemmele, Electrochemistry of Redox-active Group 15/16 Heterocycles, Coord. Chem. Rev., 210, 369 (2000). [Pg.12]

Macroheterocycles as components of photo- and redox-active host ensembles 98PAC2359. [Pg.218]

Electrochemical measurements are commonly carried out in a medium that consists of solvent containing a supporting electrolyte. The choice of the solvent is dictated primarily by the solubility of the analyte and its redox activity, and by solvent properties such as the electrical conductivity, electrochemical activity, and chemical reactivity. The solvent should not react with the analyte (or products) and should not undergo electrochemical reactions over a wide potential range. [Pg.102]

Fig. 6. Theoretical cyclic voltammogram for a redox-active polymer film with noninteracting redox centres... Fig. 6. Theoretical cyclic voltammogram for a redox-active polymer film with noninteracting redox centres...
A great variety of suitable polymers is accessible by polymerization of vinylic monomers, or by reaction of alcohols or amines with functionalized polymers such as chloromethylat polystyrene or methacryloylchloride. The functionality in the polymer may also a ligand which can bind transition metal complexes. Examples are poly-4-vinylpyridine and triphenylphosphine modified polymers. In all cases of reactively functionalized polymers, the loading with redox active species may also occur after film formation on the electrode surface but it was recognized that such a procedure may lead to inhomogeneous distribution of redox centers in the film... [Pg.53]

A very similar idea is the use of ion exchanging polymers into which redox active ions can be incorporated by equilibration with an adherent solution. Sulfonated perfluoro polymers (Nafion), polyvinylsulfonic acid , and polystyrene... [Pg.53]

A two-step synthetic procedure to isomeric redox-active metallocyclophanes Mo(NO)Tp (4,4 -OC. [Pg.340]

These studies of protein-bound heterometallic cubanes have amply demonstrated that the heterometal site is redox active and able to bind small molecules. Although they have yet to be identified as intrinsic components of any protein or enzyme (except as part of the nitrogenase FeMo cofactor cluster (254)), they are clearly attractive candidates for the active sites of redox enzymes. [Pg.68]

Spectroscopic studies have been instrumental in elucidating the catalytic mechanism of Ni-Fe hydrogenases. A great deal of controversy concerning this mechanism arises from the fact that, as the as the X-ray crystallographic analysis has shown, there are at least three potential redox-active species at the enzyme s active site the thiolate ligands (75) and the Fe (65) and Ni (9) ions. [Pg.292]

If the Fe-Ni center is not redox active, at least during catalysis, then the process must be ligand-based (92). Maroney and co-workers have argued that the paramagnetic Ni-C state could be generated by the interaction of a thyil radical with a Ni(II) ion. This species is isoelectronic with a thiolate-bound Ni(III) according to the reaction... [Pg.300]

The [NiFe] hydrogenase from D. gigas has been used as a prototype of the [NiFe] hydrogenases. The enzyme is a heterodimer (62 and 26 kDa subunits) and contains four redox active centers one nickel site, one [3Fe-4S], and two [4Fe-4S] clusters, as proven by electron paramagnetic resonance (EPR) and Mosshauer spectroscopic studies (174). The enzyme has been isolated with different isotopic enrichments [6 Ni (I = I), = Ni (I = 0), Fe (I = 0), and Fe (I = )] and studied after reaction with H and D. Isotopic substitutions are valuable tools for spectroscopic assignments and catalytic studies (165, 166, 175). [Pg.390]

These enzymes may contain other redox-active sites (iron-sulfur centers, hemes, and/or flavins), either in distinct domains of a single polypeptide or bound in separate subunits. These additional cofactors perform electron transfer from the molybdenum center to an external electron acceptor/donor. [Pg.396]

The protein from D. desulfuricans has been characterized by Mbss-bauer and EPR spectroscopy 224). The enzyme has a molecular mass of approximately 150 kDa (three different subunits 88, 29, and 16 kDa) and contains three different types of redox-active centers four c-type hemes, nonheme iron arranged as two [4Fe-4S] centers, and a molybdopterin site (Mo-bound to two MGD). Selenium was also chemically detected. The enzyme specific activity is 78 units per mg of protein. [Pg.403]

Transition Metal and Organic Redox-Active Macrocycles Designed to Electrochemically Recognize Charged and Neutral Guest Species Paul D. Beer... [Pg.512]


See other pages where Redox activation is mentioned: [Pg.2972]    [Pg.2980]    [Pg.2988]    [Pg.2989]    [Pg.348]    [Pg.351]    [Pg.442]    [Pg.442]    [Pg.66]    [Pg.393]    [Pg.97]    [Pg.266]    [Pg.1061]    [Pg.21]    [Pg.79]    [Pg.89]    [Pg.82]    [Pg.178]    [Pg.185]    [Pg.53]    [Pg.53]    [Pg.62]    [Pg.75]    [Pg.20]    [Pg.7]    [Pg.8]    [Pg.11]    [Pg.63]    [Pg.303]    [Pg.379]    [Pg.382]    [Pg.407]   
See also in sourсe #XX -- [ Pg.97 ]

See also in sourсe #XX -- [ Pg.78 ]




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Activity redox

Adenosine triphosphate , redox-active

Ammonium redox-active macrocycles

Berlin green/Prussian blue redox activity

Bimetallic catalysis redox active metal ions

Biosensor redox-active molecules

Bovine heart redox-active metal sites

Catechol ligands, redox activity

Chemically redox active

Complexes Containing Redox-active Ligands

Complexes with Redox-active -Conjugated Polymers

Composites redox-active materials

Coordinated transition metal redox-active macrocycles

Cryptands redox-active

Dendrimer redox-active units

ER Measurements for Redox-active Thin Organic Films

Electrochemical recognition of anionic guest species by redox-active receptor molecules

Electrochemical recognition of charged and neutral guest species by redox-active

Electrochemical recognition of charged and neutral guest species by redox-active receptor

Electrochemical recognition of charged and neutral guest species by redox-active receptor molecules

Electrochemical redox active electrodes

Electrochemistry of Thin Redox-Active Polymer films

Electrodes redox active

Enzymatic activities redox enzymes

Ferrocene units redox-active monolayers

Functions of the Redox-Active Metal Sites in This Enzyme

Intercalative redox active probe

Less Known Redox-active Ligands in Metal Complexes

Ligand, additivity redox-active

Lumophore-spacer-receptor systems with redox active guests

Membranes redox-active

Mesoporous active redox framework

Metal redox active centres

Molecular redox-active molecule

Nitrogenase redox activation

Nitrosylmetal complexes with additional redox-active ligands

Nitrosylmetal complexes without additional redox-active ligands

Noble metal particles, redox-active

Nonlinear optical activities redox switching

O2 with Active Sites and the Redox Mechanism

Oligothiophenes containing redox-active groups

Organoaluminum Complexes Incorporating Redox-Active Ligands

Oxidative stress from redox-active metals

Photosystem redox activity

Polyaniline redox activity

Probe electrochemical/redox-active

Proteins redox-active

Reactions of Redox-Activated Complexes with Gaseous Substrates

Receptor molecules, redox-active

Receptor molecules, redox-active electrochemical recognition

Receptor molecules, redox-active, electrochemical recognition of charged and

Receptor molecules, redox-active, electrochemical recognition of charged and neutral

Receptor molecules, redox-active, electrochemical recognition of charged and neutral guest

Receptor molecules, redox-active, electrochemical recognition of charged and neutral guest species

Receptors redox-active

Receptors redox-active center

Redox Activity of Metallointercalators

Redox State and Biologic Activity

Redox activation mechanism

Redox activation, electrochemical mode

Redox active biomolecules

Redox active bridging ligands

Redox active catenane

Redox active chemically modified electrode

Redox active cofactors

Redox active disulfide

Redox active groups

Redox active material

Redox active metal ions

Redox active molecular orbital

Redox active molecular orbital RAMO)

Redox active molecular orbitals

Redox active zeolites

Redox activity determination

Redox activity potential

Redox activity supercapacitors

Redox activity switching

Redox catalytic activity

Redox chemistry, electrically active polymer

Redox coupling activation

Redox reactions activity series of metals

Redox regulation kinase activity

Redox-Activated Chemical (EC) Reactions

Redox-Active Aqueous Electrolytes

Redox-Active Aqueous Electrolytes for Carbon Electrodes

Redox-Active Aqueous Electrolytes for Pseudocapacitive Electrodes

Redox-Active Conjugated Polymer-Based Recognition

Redox-Active Electrolytes

Redox-Active Polyferrocenylsilane Gels

Redox-Active Solid-State Electrolytes

Redox-activated Xenobiotics

Redox-activated reactions

Redox-activated reactions chemically reactive species

Redox-activated reactions reference electrodes

Redox-activated switches

Redox-active

Redox-active -Conjugated Systems

Redox-active MOFs

Redox-active agents

Redox-active amino acids

Redox-active amino acids molecular structure

Redox-active cavitand host molecules

Redox-active cellular constituents

Redox-active centers

Redox-active centers electron transfer

Redox-active centers spectroscopic features

Redox-active cobalt

Redox-active complexes

Redox-active core dendrimers

Redox-active cyclophane

Redox-active dendrimer

Redox-active dendrimer films

Redox-active dendrimers

Redox-active dendrimers metal complexes

Redox-active dendrimers transition metal complexes

Redox-active dyes

Redox-active guests

Redox-active guests cucurbituril complexation

Redox-active guests cyclodextrin complexation

Redox-active ligands

Redox-active ligands dithiolenes

Redox-active ligands ferrocenes

Redox-active ligands polypyridines

Redox-active ligands porphyrins

Redox-active metal-polypyridine

Redox-active metal-polypyridine dendrimers

Redox-active metals

Redox-active monolayers, electrochemical

Redox-active photochromic

Redox-active polymers, deposition onto

Redox-active probe

Redox-active probe molecules

Redox-active prosthetic groups

Redox-active systems

Redox-active systems electrochemical properties

Redox-active systems supramolecular development

Redox-active transition metals

Redox-active transition-metal sandwiche

Rotaxane redox active

Rotaxanes redox-active units

SUBJECTS Redox activity

Silica redox-active

Single-stranded nucleic acids, redox-active

Spectroscopy redox active electrodes

Structures and Spectral Properties of the Redox-Active Metal Sites

Superoxide dismutase, redox-active

Superoxide dismutase, redox-active enzyme

Tetrathiafulvalene redox-active

The Activity Series Predicting Spontaneous Redox Reactions

The Direct Electrochemistry of Redox-active Proteins

Thermodynamic aspects, redox active

Thin redox-active polymer

Towards electrochemical recognition of neutral guest species by redox-active receptor molecules

Transition Metal and Organic Redox-Active Macrocycles Designed

Vanadium compounds redox activity

Viologen derivatives, redox-active

Water hydroxide, redox activation

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