Results 171 to 180 of about 9,393 (223)

Metalloporphyrin chelatase from barley

Biochimica et Biophysica Acta (BBA) - Enzymology, 1969
1. 1. A soluble enzyme which catalyzes the insertion of both zinc and iron into porphyrins has been prepared from etiolated barley seedlings. Purification of about 30-fold has been achieved by (NH4)2SO4 fractionation and chromatography on Sephadex G-150.
B R, Goldin, H N, Little
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Halogenation of metalloporphyrins

Russian Journal of Bioorganic Chemistry, 2000
We found that thionyl chloride can chlorinate porphyrin complexes with transient metals (Pd, Ni, or Cu) at the free β andmeso-positions of the porphyrin macrocycle. A more prolonged or rigorous treatment also causes the chlorination of side alkyl substituents, mainly, methyl groups.
V. D. Rumyantseva, E. A. Aksenova, O. N. Ponamoreva, A. F. Mironov   +3 more
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Spectroelectrochemistry of metalloporphyrins

Pure and Applied Chemistry, 1990
Abstract
K. M. Kadish, X. Mu
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Hydrogen Generation by Hangman Metalloporphyrins

Journal of the American Chemical Society, 2011
A cobalt(II) hangman porphyrin with a xanthene backbone and a carboxylic acid hanging group catalyzes the electrochemical production of hydrogen from benzoic and tosic acid in acetonitrile solutions. We show that Co(II)H is exclusively involved in the generation of H(2) from weak acids.
Chang Hoon, Lee, Dilek K, Dogutan, Daniel G, Nocera   +2 more
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Electrocatalysis of metalloporphyrins

Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1990
Abstract The electrocatalytic reduction of cystine with water-soluble cobalt(II) tetrakis(4-trimethylammoniumphenyl)porphyrin (CoTTAPP) and cobalt(II) tetrakis(4-sulphophenyl)porphyrin (CoTSPP) in 0.2 M H 2 SO 4 solution was investigated. The experimental results of cyclic voltammetry and the rotating disc electrode technique indicated that both ...
Dai-Wen Pang, Zong-Li Wang
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Niedrigschmelzende, flüssigkristalline Metalloporphyrine

Angewandte Chemie, 1997
Gezielt einstellen läßt sich die Art der Mesophase durch die Wahl der Seitenketten von Porphyrinen mit vielen langen Seitenketten. Es entstehen calamitische oder columnare Phasen, deren Übergangstemperaturen niedriger sind als die der seitenkettenfreien Stammverbindungen.
Qing Min Wang, Duncan W. Bruce
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Metalloporphyrin Molecular Sieves

Chemistry – A European Journal, 2000
Crystal-engineering strategies have been systematically developed for the rational design by self-assembly of diverse metalloporphyrin molecular-sieve materials. Cooperative coordination and hydrogen bonding algorithms of molecular recognition proved particularly useful for this aim.
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Electrocatalysis on Metalloporphyrins

Russian Chemical Reviews, 1980
Results of theoretical and applied research on electrocatalytic reactions — the cathodic reduction of oxygen, hydrogen peroxide, and carbon dioxide and the anodic oxidation of organic and inorganic substances — on metalloporphyrins are analysed with a list of 132 references.
M R Tarasevich, K A Radyushkina
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Metalloporphyrin catalysts for organic synthesis

Journal of Porphyrins and Phthalocyanines, 2004
Novel chiral systems for the catalytic asymmetric oxidation and cyclopropanation of olefins based on metalloporphyrins containing iron, ruthenium and manganese, have been recently introduced. High catalyst turnover numbers and sometimes high enantiomeric excess were observed.
Simonneaux, G, TAGLIATESTA, PIETRO
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Out-of-plane metalloporphyrin complexes

Journal of Chemical Education, 1975
Abstract : Recent progress in the chemistry of synthetic metalloporphyrins has shown that the porphyrin moiety can act as a bi-, tri- or hexadentate ligand, as well as the usual tetradentate ligand. In addition, the metal ion has been observed to possess 4, 5, 6 or 8-coordination.
G A, Taylor, M, Tsutsui
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