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The release of iron from horse spleen ferritin to 1,10-phenanthroline.

ABSTRACT: The rate of release of iron to 1,10-phenanthroline from ferritin fractions of different iron contents has been studied. The experimental results could be interpreted by a simple hypothetical model of the shape of the hydrous ferric oxide micelle at different iron contents, and reasonable correlation obtained between the rate of release and the calculated micelle surface areas. Initial rates of release did not correlate significantly with protein concentration.

SUBMITTER: Hoy TG

PROVIDER: S-EPMC1166081 | biostudies-other | 1974 Jan

REPOSITORIES: biostudies-other

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The release of iron from horse spleen ferritin by reduced flavins.

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Project description:In the title compound, [Mg(C(12)H(8)N(2))(2)(H(2)O)(2)][Cr(2)O(7)]·2C(12)H(8)N(2), the cation and anion are situated on a twofold rotation axis. The Mg(II) ion is coordinated by four N atoms from two 1,10-phenanthroline ligands and two O atoms from coordinated water mol-ecules in a distorted octa-hedral geometry. Inter-molecular O-H⋯N and O-H⋯O hydrogen bonds and π-π inter-actions between the aromatic rings [shortest centroid-centroid separation = 3.527 (2) Å] link the cations, anions and 1,10-phenanthroline solvent mol-ecules into a hydrogen-bonded cluster.

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Questions about horse spleen ferritin crossing the blood brain barrier via mouse transferrin receptor 1.

Project description: Not available

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Ligands with 1,10-phenanthroline scaffold for highly regioselective iron-catalyzed alkene hydrosilylation.

Project description:Transition-metal-catalyzed alkene hydrosilylation is one of the most important homogeneous catalytic reactions, and the development of methods that use base metals, especially iron, as catalysts for this transformation is a growing area of research. However, the limited number of ligand scaffolds applicable for base-metal-catalyzed alkene hydrosilylation has seriously hindered advances in this area. Herein, we report the use of 1,10-phenanthroline ligands in base-metal catalysts for alkene hydrosilylation. In particular, iron catalysts with 2,9-diaryl-1,10-phenanthroline ligands exhibit unexpected reactivity and selectivity for hydrosilylation of alkenes, including unique benzylic selectivity with internal alkenes, Markovnikov selectivity with terminal styrenes and 1,3-dienes, and excellent activity toward aliphatic terminal alkenes. According to the mechanistic studies, the unusual benzylic selectivity of this hydrosilylation initiates from ?-? interaction between the phenyl of the alkene and the phenanthroline of the ligand. This ligand scaffold and its unique catalytic model will open possibilities for base-metal-catalyzed hydrosilylation reactions.

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Project description:Single crystals of the title heterometallic compound, [Fe(C(12)H(8)N(2))(3)][Cr(NCS)(4)(C(12)H(8)N(2))](2)·3CH(3)CN·H(2)O or [Fe(Cphen)(3)][Cr(NCS)(4)(phen)](2)·3CH(3)CN·H(2)O, were pre-pared using the one-pot open-air reaction of iron powder, Reineckes salt and 1,10-phenanthroline (phen) in acetonitrile. The asymetric unit consists of an [Fe(phen)(3)](2+) cation, two [Cr(phen)(NCS)(4)](-) anions, three acetonitrile solvent mol-ecules and a water mol-ecule. The Fe and Cr atoms both show a slightly distorted octa-hedral FeN(6) and CrN(6) coordination geometry with adjacent angles in the range 79.67?(12)-95.21?(12)°. No classical hydrogen bonding involving the water molecule is observed.

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