Modification of the metal's electronic environment by ligand association and dissociation in metalloenzymes is considered cardinal to their catalytic activity. We have recently presented a novel system that utilizes the bacteriochlorophyll (BChl) macrocycle as a ligand and reporter. This system allows for charge mobilization in the equatorial plane and experimental estimate of changes in the el...

Some meso-tetra aryl porphyrinato manganese (III) acetate or chloride complexes including meso-tetraphenyl porphyrinato manganese (III) chloride (TPPMnCl), meso-tetrakis(2,3-dimethoxyphenyl)porphyrinato manganese(III) acetate, (T(2,3-OMeP)PMnOAc) and meso-tetrakis(pentaflourophenyl)porphyrinato manganese (III) acetate (TPFPPMnOAc) were synthesized. These porphyrins were used as catalyst in the ...

In the title salt, (C(8)H(20)N)[ReBr(C(7)H(5)O(2))(CO)(3)], the Re(I) atom is octa-hedrally surrounded by three facially orientated carbonyl ligands, one bidendate tropolonate ligand and a bromide ligand. The small O-Re-O bite angle of 74.88 (12)° leads to a distortion of the octa-hedral coordination sphere. The bromide ligand and the axial carbonyl ligand are substitutionally disordered over t...

In the title mononuclear copper(II) compound, [Cu(C(2)O(4))(C(4)H(12)N(2)O)], the Cu(II) ion has a slightly distorted square-pyramidal geometry, with a tridentate N-(2-hydroxy-ethyl)ethyl-enediamine (HydEt-en) and a bidentate oxalate (ox) ligand. The N atoms of the HydEt-en ligand and the O atoms of ox ligand form the basal plane, while the O atom of the ethanol group of the HydEt-en ligand is ...

The title compound, [Mn(C(18)H(12)N(4)O(2))(C(4)H(6)N(2))(2)], belongs to the family of 1,2-bis-(pyridine-2-carboxamido)benzene (H(2)bpb) ligated metal complexes. The manganese center is octa-hedrally coordinated by a bpb ligand and two axial 1-methyl-imidazole mol-ecules. The axial N-Mn-N group is bent with a bond angle of 151.79 (7)°.

This is a report of the studies conducted on synthesis, spectral, biological viz. antibacterial and antitumorous activities some Copper complexes synthesized from multidentate thiosemicarbazone ligand, HL2. based reaction between secondary amine viz.N-phenyl piperazine an N-substituted heterocyclic ketone 2-Benzoylpyridine. The ligand exhibits mode coordination through N,N,S donor atoms in copp...

Manganese protoporphyrin IX was recombined with apoproteins of cytochrome c peroxidase, horseradish peroxidase, myoglobin, and hemoglobin to prepare artificial hemoproteins containing the manganese porphyrin in place of protoheme or iron protoporphyrin IX. Electron paramagnetic resonance (EPR) spectra of manganese (II) protoporphyrin IX and its apohemoprotein complexes were measured at Xand K-b...

The vibrational spectra of two five-coordinate nitrosyl iron porphyrinates, [Fe(OEP)(NO)] (OEP = dianion of 2,3,7,8,12,13,17,18-octaethylporphyrin) and [Fe(DPIX)(NO)] (DPIX = deuteroporphyrin IX), have been studied by oriented single-crystal nuclear resonance vibrational spectroscopy. Single crystals (both are in the triclinic crystal system) were oriented to give vibrational spectra perpendicu...

We use two-dimensional hyperfine sublevel correlation (HYSCORE) spectroscopy to investigate the coordination geometry of the nitrogen ligands of biomimetic models of the oxygen-evolving complex of photosystem II. In the 2D HYSCORE spectroscopy study, [(bpy)2Mn(III)(μ-O)2Mn(IV)(bpy)2](ClO4)3 (bpy, 2,2'-bipyridine) (1) and [H2O(terpy)Mn(III)(μ-O)2Mn(IV)(terpy)OH2](NO3)3 (terpy = 2,2':6',2″-terpyr...