Bis[μ-(benzoato-<i>O</i>,<i>O</i>')]-bis(benzoato)-bis[μ-(2-dibutylaminoethanolato)]-bis(ethanol)tricopper(II)

Muhonen, H.; Pajunen, A.; Hämäläinen, Reijo

doi:10.1107/s0567740880010059

Cited by 15 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the orbital pathways by which the two metal centers can communicate are very different for a μ-(η 1 ,η 2 ) bridging carboxylate and a μ-1,3 bridging carboxylate. μ-(η 1 ,η 2 ) bridges are observed to lead to ferromagnetic coupling, − as in biferrous MMO, which has a similar ligand set. − The major bonding interaction between the iron atoms and the bridging carboxylate oxygen is σ in nature. The oxygen p-orbital on the μ-(η 1 ,η 2 ) carboxylate which σ-bonds with a half-occupied orbital on Fe1 (bottom carboxylate in Figure a) is oriented perpendicularly to the carboxylate oxygen p-orbital which σ-bonds with the half-occupied orbital on Fe2 (bottom carboxylate in Figure b).…”

Section: Results and Analysismentioning

confidence: 99%

“…However, the orbital pathways by which the two metal centers can communicate are very different for a µ-(η 1 ,η 2 ) bridging carboxylate and a µ-1,3 bridging carboxylate. µ-(η 1 ,η 2 ) bridges are observed to lead to ferromagnetic coupling, [65][66][67] as in biferrous MMO, which has a similar ligand set. [68][69][70][71] The major bonding interaction between the iron atoms and the bridging carboxylate oxygen is σ in nature.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity

et al. 2004

View full text Add to dashboard Cite

Circular dichroism (CD), magnetic circular dichroism (MCD), and variable-temperature variable-field (VTVH) MCD have been used to probe the biferrous active site of two variants of ribonucleotide reductase. The aspartate to glutamate substitution (R2-D84E) at the binuclear iron site modifies the endogenous ligand set of ribonucleotide reductase to match that of the binuclear center in the hydroxylase component of methane monooxygenase (MMOH). The crystal structure of chemically reduced R2-D84E suggests that the active-site structure parallels that of MMOH. However, CD, MCD, and VTVH MCD data combined with spin-Hamiltonian analysis of reduced R2-D84E indicate a different coordination environment relative to reduced MMOH, with no mu-(1,1)(eta(1),eta(2)) carboxylate bridge. To further understand the variations in geometry of the active site, which lead to differences in reactivity, density functional theory (DFT) calculations have been carried out to identify active-site structures for R2-wt and R2-D84E consistent with these spectroscopic data. The effects of varying the ligand set, positions of bound and free waters, and additional protein constraints on the geometry and energy of the binuclear site of both R2-wt and variant R2s are also explored to identify the contributions to their structural differences and their relation to reduced MMOH.

show abstract

Section: Results and Analysismentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity

et al. 2004

View full text Add to dashboard Cite

show abstract

“…The full proposed structure is the dimeric 2 (Scheme ). Consistent with this picture, the ability of polyamino alcohol ligands to coordinate in the alkoxo form to copper(II) and to promote dimer formation is well-documented. , We note that we cannot distinguish between symmetrical dimers with bridging alkoxide groups vs those hydrogen-bonded through alternating alcohol−alkoxide ligands 3 2 Electronic Spectroscopic Parameters for 3 and Related Complexes complexabs λ max (nm) (ε, M -1 cm -1 )CD λ max (nm) (Δε, M -1 cm -1 )solvent [Cu( l -phe) 2] 619 (74.5) DMSO [Cu(gly)(Cl)(CH 3 OH)] 742 ( a ) CH 3 OH 2 631 (71.6 b ) DMSO 3 665 (104) DMSO 3 664 ( a ) CH 3 OH 3 679 (85) 544 (+0.35 c ) phosphate buffer d 3 624 (−0.19 c ) phosphate buffer d 3 743 (+0.70 c ) phosphate buffer d a not determined.

…”

Section: Resultsmentioning

confidence: 62%

A Trapped Intermediate in the Copper(II)-Mediated Template Synthesis of an Amino Acid-Containing Ligand

Villanueva

Bocarsly

1997

Inorg. Chem.

View full text Add to dashboard Cite

A transition metal ion-templating reaction that has been widely exploited for the synthesis of nitrogen macrocycles, sepulchrates, and linear tetradentate ligands is the template-directed Mannich condensation of carbon acid and aldehyde equivalents with amines. In the course of investigating the copper(II) template-directed synthesis of linear tetradentate amino acid-containing ligands for the design and synthesis of double-strand DNA cleavage agents, we have trapped and characterized an intermediate in the templating reaction. Condensation of bis(phenylalaninato)copper(II) with formaldehyde and nitroethane led to a nitro-substituent-bearing precursor complex that upon reduction is crystallographically characterized as ((2S)-5-amino-2-benzyl-6-hydroxy-5-methyl-3-azahexanoate)copper(II) (space group P2(1)2(1)2(1), a = 9.0066(5) Å, b = 11.1040(6) Å, c = 16.009(2) Å, alpha = beta = gamma = 90.0 degrees, Z = 4, R(1) = 0.0265, wR(2) = 0.0612). NMR investigation of the precursor complex and the precursor and product ligands shows that the templated ligands each contain only a single phenylalanine unit, not the two phenylalanine units expected on the basis of similar synthetic procedures. The structure of the reduced product confirms this conclusion and provides structural characterization of a template intermediate trapped during ligand assembly.

show abstract

Synthesis, Structure, Spectroscopy, and Magnetism of Unique Propeller-Type Linear Trinuclear CuII Complexes with In-situ Prepared Formamidine Ligands

Albada

Koningsbruggen

Mutikainen

et al. 1999

Eur. J. Inorg. Chem.

View full text Add to dashboard Cite

Bis[μ-(benzoato-O,O')]-bis(benzoato)-bis[μ-(2-dibutylaminoethanolato)]-bis(ethanol)tricopper(II)

Cited by 15 publications

References 2 publications

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity

A Trapped Intermediate in the Copper(II)-Mediated Template Synthesis of an Amino Acid-Containing Ligand

Synthesis, Structure, Spectroscopy, and Magnetism of Unique Propeller-Type Linear Trinuclear CuII Complexes with In-situ Prepared Formamidine Ligands

Contact Info

Product

Resources

About

Bis[μ-(benzoato-O,O')]-bis(benzoato)-bis[μ-(2-dibutylaminoethanolato)]-bis(ethanol)tricopper(II)

Cited by 15 publications

References 2 publications

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O2 Reactivity

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O2 Reactivity

A Trapped Intermediate in the Copper(II)-Mediated Template Synthesis of an Amino Acid-Containing Ligand

Synthesis, Structure, Spectroscopy, and Magnetism of Unique Propeller-Type Linear Trinuclear CuII Complexes with In-situ Prepared Formamidine Ligands

Contact Info

Product

Resources

About

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity

Electronic and Spectroscopic Studies of the Non-Heme Reduced Binuclear Iron Sites of Two Ribonucleotide Reductase Variants: Comparison to Reduced Methane Monooxygenase and Contributions to O₂ Reactivity