Zur Existenz von [ReNCl4-nFn]- (n = 1-3) Nitridorhenat(VI)-Gemischt- ligandkomplexen -Eine EPR-Untersuchung / EPR Evidence of [ReNCl4-n FnJ– (n = 1-3) Nitridorhenate(VI) Mixed-Ligand Complexes

1998 ◽  
Vol 53 (10) ◽  
pp. 1183-1187 ◽  
Author(s):  
Andreas Voigt ◽  
Ulrich Abram ◽  
Reinhard Kirmse
Keyword(s):  
Spectral Data ◽  
Coordination Sphere ◽  
Linear Dependence ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Additivity Rules ◽  
Hyperfine Splittings ◽  
Frozen Solutions ◽  
The Individual

AbstractThe formation of mixed-ligand complexes of the type [ReVlNCl4-nFn]- (n = 1 -3) during the reaction of [ReVINCl4]- with [n-(C4H9)4N]F, KF, and HF is reported. Evidence of the individual mixed-ligand compounds is given by their EPR spectral data. In frozen solutions a specific dependence of the EPR data on the composition of the coordination sphere could be detected. This is shown (i) by a nearly linear dependence of gII and AII Re on the Cl/F-content of the [ReVINCl4-nFn]- unit (additivity rules) and (ii) by well-resolved 19F hyperfine splittings.

Ternary Complexes in Solution, XII. Models for Biological Mixed-Ligand Complexes: 2,2′-Bipyridyl-Cu2+-Oligoglycine Systems

1972 ◽  
Vol 27 (4) ◽  
pp. 353-364 ◽  
Author(s):  
Helmut Sigel ◽  
Rolf Griesser ◽  
Bernhard Prijs
Keyword(s):  
Coordination Sphere ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Amide Group ◽  
Amide Proton ◽  
Mixed Ligand Complexes ◽  
Apical Position ◽  
Binary Complexes ◽  
The Stability ◽  
Ph Range

The stability constants of the binary Cu2+ complexes of glycine amide, diglycine, diglycine amide, triglycine, and tetraglycine were determined, as were those of the mixed-ligand Cu2+ systems containing 2,2′-bipyridyl and one of the mentioned oligoglycines. The results evidence that all these complexes have the same structure and, therefore, the binding sites of the ligands have to be the terminal amino group and the oxygen of the neighbored amide group. The stability differences between the ternary and the binary complexes are in agreement with this interpretation. It is of interest to note that these ternary complexes are significantly more stable than expected on statistical reasons. With increasing pH, the amide groups in the binary complexes are successively deprotonated. Thus, with tetraglycine finally all three amide protons are displaced, and the amide nitrogens are bound to the square-planar coordination sphere of Cu2+. As in the Cu2+-2,2′-bipyridyl 1 : 1 complex, only two coordination positions are left for the binding of the oligoglycine, in the tenary complexes, only one amide group can be deprotonated. An increase in pH with deprotonation of other amide groups leads to a displacement of 2,2′-bipyridyl, i. e. the simple binary complexes result. No evidence could be observed for the coordination of a deprotonated amide group to an apical position of the coordination sphere of Cu2+. Additionally, while the displacement of the first amide proton in the several binary Cu2+ oligoglycine complexes occurs over a large pH range (4 to 7), the deprotonation in all the mixed-ligand complexes takes place at pH approximately 8.

Mixed-ligand complexes of technetium VI. Nitridotechnetium(V) complexes with equatorial ,P-coordination sphere

1989 ◽  
Vol 162 (2) ◽  
pp. 171-173 ◽  
Author(s):  
Ulrich Abram ◽  
Rudolf Münze ◽  
Ernst-Gottfried Jäger ◽  
Joachim Stach ◽  
Reinhard Kirmse
Keyword(s):  
Coordination Sphere ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes

scholarly journals Preparation and Antibacterial Activity of Mixed Ligand Complexes of Co(II), Ni(II), Cu(II) and Cd(II) Derived from 1-Phenylazo-2-naphthol and Salicylaldehyde

2011 ◽  
Vol 8 (1) ◽  
pp. 43-48
Author(s):  
S. A. I. Sharif ◽  
A. N. El-Tajoury ◽  
A. A. Elamari
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Antibacterial Activity ◽  
Spectral Data ◽  
Electronic Absorption ◽  
Molar Conductance ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Central Metal ◽  
Paramagnetic Resonance ◽  
Electron Paramagnetic

The mixed ligand complexes of Co(II), Ni(II), Cu(II) and Cd(II) have been synthesized by using 1-phenylazo-2-naphthol as primary ligand and salicylaldehyde as secondary ligand. All the prepared complexes were identified and confirmed by elemental analyses (C, H and N), molar conductance measurements, infrared, electronic absorption and electron paramagnetic resonance. The elemental analysis data suggest that the stoichiometry of the complexes to be 1:1:1[M: L1: L2] ratio. The molar conductance measurements of the complexes indicate their non-electrolytic nature. The infrared spectral data showed the coordination sites of the free ligand with the central metal ion. The electronic absorption spectral data revealed the existence of an octahedral geometry for Co(II) and Cd(II) complexes and a square planar geometry for Ni(II) and Cu(II) complexes. The electron paramagnetic resonance spectra of the Co(II) and Cu(II) complexes showed the existence a paramagnetic phenomenon and supported their geometrical structures which confirmed by the electronic absorption spectra. The ligands and mixed ligand complexes have been tested on antibacterial activity against three strains of pathogenic bacteria such asEscherichia coli, Staphylococcus aureusandPseudomonas aeruginosa

scholarly journals MONO- AND MIXED- LIGAND COMPLEXES OF Yb(III) WITH NEW β-DIKETONES

2021 ◽  
Vol 87 (2) ◽  
pp. 65-76
Author(s):  
Nadiia Ivakha ◽  
Oleksandra Berezhnytska ◽  
Oleksandr Rohovtsov ◽  
Nataliia Rusakova ◽  
Olena Trunova
Keyword(s):  
Coordination Sphere ◽  
Coordination Polyhedron ◽  
Emission Intensity ◽  
Chemical Structure ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Antenna Effect ◽  
Cubic Symmetry ◽  
Relative Emission Intensity ◽  
Ytterbium Ion

New ytterbium (III) compounds with β-diketones (2,7-dimethyl-octene-1-dione-3,5 and 2,6-dimethylheptene-1-dione-3,5) and their derivatives with phenanthroline have been synthesized. The composition and chemical structure of the obtained complexes have been determined by several Phy­sico-chemical investigations. It has been shown, that the Yb (III) ion coordinates three ligand molecules and the coordination sphere of the complexes is supplemented by two mole­cules of water or a molecule of phenanthroline. It has been shown that the СN of the ytterbium ion is 8, the coordination polyhedron is a square antiprism, and the complex is characte­rized by no cubic symmetry. All synthesized compounds exhibit intense IR luminescence. The significant increase in the relative emission intensity of mixed ligand complexes is due to the additional antenna effect of the phenanthroline molecule.

Mixed ligand-metal Complexes of 2-(butan-2-ylidene) hydrazinecarbothioamide- Synthesis, Characterization, Computer Aided Drug Character Evaluation and in vitro Biological Activity Assessment

2019 ◽  
Vol 15 ◽  
Author(s):  
Tahmeena Khan ◽  
Rumana Ahmad ◽  
Iqbal Azad ◽  
Saman Raza ◽  
Seema Joshi ◽  
...  
Keyword(s):  
Molecular Docking ◽  
Metal Complexes ◽  
Condensation Reaction ◽  
Dose Range ◽  
Biological Significance ◽  
Mixed Ligand ◽  
Binding Energies ◽  
Mixed Ligand Complexes ◽  
E Coli ◽  
Topo Ii

Background: Mixed ligand-metal complexes are efficient chelating agents because of flexible donor ability. Mixed ligand complexes containing hetero atoms sulphur, nitrogen and oxygen have been probed for their biological significance. Objective: Nine mixed ligand-metal complexes of 2-(butan-2-ylidene) hydrazinecarbothioamide (2-butanone thiosemicarbazone) and pyridine, bipyridine or 2-picoline as co-ligands were synthesized with Cu, Fe and Zn. The complexes were tested against MDA-MB231 (MDA) and A549 cell lines. Antibacterial activity was tested against S. aureus and E. coli. The drug character of the complexes was evaluated on several parameters viz. physicochemical properties, bioactivity scores, toxicity assessment and absorption, distribution, metabolism, excretion and toxicity (ADMET) profile assessment using various automated softwares. Molecular docking of the complexes was also performed with two target proteins. Method and Results: The mixed ligand-metal complexes were synthesized by condensation reaction for 4-5 h. The characterization was done by elemental analysis, 1H-NMR, FT-IR, molar conductance and UV spectroscopies. Molecular docking was performed against ribonucleotide reductase (RR) and topoisomerase II (topo II). [Cu(C5H11N3S)(py)2(CH3COO)2], [Zn(C5H11N3S)(bpy)(SO4)] and [Zn(C5H11N3S)(2-pic)2(SO4)] displayed the lowest binding energies with respect to RR. Against topo II [Cu(C5H11N3S)(py)2(CH3COO)2], [Cu(C5H11N3S)(bpy)(CH3COO)2] and [Zn(C5H11N3S)(2-pic)2(SO4)] had the lowest energies. The druglikness assessment was done using Leadlikeness and Lipinski’s rules. Against topo II [Cu(C5H11N3S)(py)2(CH3COO)2], [Cu(C5H11N3S)(bpy)(CH3COO)2] and [Zn(C5H11N3S)(2-pic)2(SO4)] had the lowest energies. Not more than two violations were obtained in case of each filtering rule showing drug like character of the mixed ligand complexes. Several of the complexes exhibited positive bioactivity scores and almost all the complexes were predicted to be safe with no hazardous effects. All the complexes were predicted to have no mutagenic character as shown by the Ames test [Zn(C5H11N3S)(py)2(SO4)] showed potential activity against MDA. [Co(C5H11N3S(bpy)(Cl)2] was also active against MDA. [Cu(C5H11N3S)(2-pic)2(CH3COO)2] also showed 27.6% cell viability at 100 µM against MDA. Against A549 [Co(C5H11N3S)(py)2(Cl)2], [Cu(C5H11N3S)(py)2(CH3COO)2] and [Co(C5H11N3S(bpy)(Cl)2] were active. [Co(C5H11N3S)(bpy)(Cl)2] and [Cu(C5H11N3S)(2-pic)2(CH3COO)2] were active against S. aureus. [Co(C5H11N3S)(2-pic)2(Cl)2] and [Zn(C5H11N3S)(2-pic)2(SO4)] were active at lower concentrations against S.aureus. Against E. coli, [Zn(C5H11N3S)(2-pic)2(SO4)] showed activity at 18-20mg dose range.

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