Sökning: "biomimetic oxidation"

Visar resultat 16 - 20 av 22 avhandlingar innehållade orden biomimetic oxidation.

  1. 16. An Investigation of Peroxidase Activity in Biomimetic and Biological Systems

    Författare :Ekaterina Ryabova; Kemiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; metabolism; Metabolism; enzymologi; Proteiner; enzymology; Proteins; hemoglobin; catalysis; peptide; peroxidase; protoporphyrin IX; Biokemi; Biochemistry;

    Sammanfattning : In order to create a heme environment which permits biomimicry of heme-containing plant peroxidases and investigate the role played by the vinyl side chains of the porphyrin ring on the stability and, possibly, catalytic activity of model compounds, a number of new synthetic microperoxidases -– hemin-6(7)-gly-his methyl ester (HGH) and hemin-6(7)-gly-gly-his methyl ester (HGGH) and hemin-6,7-bis(gly-gly-his methyl ester) (H2GGH) as well as mesohemin-6(7)-gly-gly-his methyl ester (MGGH) and deuterohemin-6(7)-gly-gly-his methyl ester (DGGH) have been prepared by condensation of a peptide residue with the propionic side chains of hemin, mesohemin and deuterohemin, respectively. Reactivity studies towards different organic and inorganic substrates showed that not only five- but also six-coordinate hemin peptide complexes catalyze the oxidation of substrates by H2O2. LÄS MER

  2. 17. New Tools for Green Catalysis : Studies on a Biomimetic Hybrid Catalyst and a Novel Nanopalladium Catalyst

    Författare :Eric Johnston; Jan Erling Bäckvall; Roger Sheldon; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; organisk kemi; Organic Chemistry;

    Sammanfattning : The first part of this thesis describes an improved synthetic route to hybrid (hydroquinone-Schiff base)cobalt catalysts. Preparation of the 5-(2,5-hydroxyphenyl)salicylaldehyde building block was improved by altering the protective groups of the hydroquinone (HQ) starting material. LÄS MER

  3. 18. Studies of Biomimtic Oxidations and Racemizations

    Författare :Gábor Csjernyik; Jan-Erling Bäckvall; Serafino Gladiali; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxidation of alcohols; ruthenium; porphyrin; racemization;

    Sammanfattning : This thesis deals with studies of ruthenium-catalyzed hydrogen transfer reactions for oxidations and racemization.Through optimisation of the substrate-selective redox catalyst, the electron and proton transfer mediator (a benzoquinone derivative), and the oxygen-activating metal macrocycle a highly efficient biomimetic oxidation of secondary alcohols was obtained. LÄS MER

  4. 19. Synthesis of Biomimetic Systems for Proton and Electron Transfer Reactions in the Ground and Excited State

    Författare :Giovanny A. Parada; Sascha Ott; Ana Moore; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Solar energy conversion; artificial photosynthesis; hydrogen bonds; excited state intramolecular proton transfer; tautomerization; proton-coupled electron transfer; photosensitizer; ruthenium complex.; Chemistry with specialization in Organic Chemistry; Kemi med inriktning mot organisk kemi;

    Sammanfattning : A detailed understanding of natural photosynthesis provides inspiration for the development of sustainable and renewable energy sources, i.e. a technology that is capable of converting solar energy directly into chemical fuels. This concept is called artificial photosynthesis. LÄS MER

  5. 20. Studies on Palladium-Catalyzed Carbocyclizations of Allene-Substituted Olefins and 1,3-Dienes

    Författare :Katja Närhi; Jan-Erling Bäckvall; Giovanni Poli; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organometallic Chemistry; Homogenous Catalysis; Palladium; Allenes; C-C bond formation; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis describes the development and mechanistic studies of carbocyclization reactions of allene-substituted olefins and 1,3-dienes, catalyzed by palladium(0) and palladium(II). These reactions results in the formation of [n,3,0] bicyclic systems (n = 3-5) with high stereoselectivity and in good to excellent yields. LÄS MER