the stability constants of species present in the systems ni(ii)-pyridoxamine(pym)(a) and ni(ii)-pyridoxamine(pym)(a)-imidazole containing ligands(b) [b = imidazole(him),  benzimidazole(bim), histamine(hist) and l-histidine(his)] have been determined ph-metrically using the miniquad computer program. the existence of the species niah, nia and nia2 was proven for the ni(ii)-pym(a) system, wherea...

Phosphine-free ruthenium benzylidene complexes containing imidazole ligands are reported. These catalysts effective for ring-closing metathesis (RCM) and cross-metathesis (CM) reactions at high temperatures, where the more widely used phosphine-containing N-heterocyclic carbene-based show side reactions. This discovery opens up a pathway to develop selective requiring harsh conditions.

Twelve new imidazole-based potential bi- and tridentate ligands were synthesized and characterized. Whereas in the first series the alpha-amino acid and imidazole moieties were linked by an amino bond, in the second series the tridentate ligands, containing two imidazole groups, were separated by an amide bond. The first series was obtained by the reductive amination of 2-phenylimidazole-4-carb...

Mono- and binuclear arene–ruthenium(II) complexes with imidazole-containing ligands were prepared by the reaction of (L1 = bis(imidazole-1-yl)methane; ImH 1H-Imidazole; BImH 1H-Benzimidazole) [(p-cym)Ru(µ-Cl)2]2 dimers. When bis(imidazole-1-yl)methane reacted in methanol, a complex type [Ru2(L1)2(p-cym)2Cl2]Cl2 (2) cyclic structure was synthesized, whereas using acetonitrile as solvent under sa...

The visible spectrum of a ligand-bound cytochrome P450 is often used to determine the nature of the interaction between the ligand and the P450. One particularly characteristic form of spectra arises from the coordination of nitrogen-containing ligands to the P450 heme iron. These type II ligands tend to be inhibitors because they stabilize the low reduction potential P450 and prevent oxygen bi...

The asymmetric unit of the title compound, [Fe(C(3)H(4)N(2))(6)]SO(4)·2C(3)H(4)N(2), contains two complex cations, two sulfate anions and four imidazole mol-ecules. In both cations, the Fe(II) atom is coordinated by six monodentate imidazole ligands and exhibits a slightly distorted octa-hedral coordination geometry. The Fe-N distances [2.184 (4)-2.218 (4) Å] point to a high-spin state of the F...

Using a metal-ligand coordination bonding approach, the self-assembly of four new metallamacrocycles from Pd(ii)-based 90 degrees acceptors and a diimidazole donor ligand 1,3-bis(imidazole-1-ylmethyl)-2,4,6-trimethylbenzene (L) has been achieved. The assemblies are characterized fully by NMR and electrospray ionization-mass spectroscopic (ESI-MS) analysis and in two cases the X-ray single-cryst...

Solution equilibrium studies on Fe(III) complexes formed with imidazole-4-carbohydroxamic acid (Im-4-Cha), N-Me-imidazole-4-carbohydroxamic acid (N-Me-Im-4-Cha), imidazole-4-acetohydroxamic acid (Im-4-Aha), and histidinehydroxamic acid (Hisha) have been performed by using pH-potentiometry, UV-visible spectrophotometry, EPR, ESI-MS, and H1-NMR methods. All of the obtained results demonstrate tha...

Copper(II) complexes of amino acids and peptides containing the chelating bis(imidazolyl) residues have been reviewed. The results reveal that bis(imidazolyl) analogues of these biomolecules are very effective ligands for metal binding. The nitrogen donor atoms of the chelating agent are the major metal binding sites under acidic conditions. In the presence of terminal amino group the multident...