Search results for "Enzimi"
showing 10 items of 286 documents
Silver(I), Copper(I) and Copper(II) Complex of the New N,Se-Chelate Ligand 2-Phenylselenomethyl-1H-benzimidazole: Electrochemistry and Structure
2009
Abstract. 2-Phenylselenomethyl-1H-benzimidazole (psbi) can form complexes in 2:1 ratio with coinage metal ions. Crystal structure analysis revealed a flattened metal coordination for [AgI(psbi)2](BF4) (1), approaching a distorted planar arrangement with weak Ag-Se bonds (d > 2.9 A) and confirmed as energy minimum by DFT calculations. The typical Jahn-Teller system [CuII(psbi)2Cl2] (2) exhibits a planar CuN2Cl2 core with weak Se---Cu---Se axial ligation (3.2944(8) A Cu--Se distance). The oxygen-sensitive compound [CuI(psbi)2](BF4) (3) exhibits electrochemically reversible oxidation in contrast to the silver(I) analogue 1.
Highly Stable and Efficient Light-Emitting Electrochemical Cells Based on Cationic Iridium Complexes Bearing Arylazole Ancillary Ligands.
2017
A series of bis-cyclometalated iridium(III) complexes of general formula [Ir(ppy)2(N∧N)][PF6] (ppy− = 2-phenylpyridinate; N∧N = 2-(1H-imidazol-2-yl)pyridine (1), 2-(2-pyridyl)benzimidazole (2), 1-methyl-2-pyridin-2-yl- 1H-benzimidazole (3), 2-(4′-thiazolyl)benzimidazole (4), 1- methyl-2-(4′-thiazolyl)benzimidazole (5)) is reported, and their use as electroluminescent materials in light-emitting electrochemical cell (LEC) devices is investigated. [2][PF6] and [3][PF6] are orange emitters with intense unstructured emission around 590 nm in acetonitrile solution. [1][PF6], [4][PF6], and [5][PF6] are green weak emitters with structured emission bands peaking around 500 nm. The different photoph…
Heterocyclic photorearrangements. Photochemical behaviour of some 3,5-disubstituted 1,2,4-oxadiazoles in methanol at 254 nm
1988
Photochemical behaviour of some 3,5-disubstituted 1,2,4-oxadiazoles in methanol at 254 nm has been investigated. Ring photoisomerization to the 1,3,4-oxadiazole heterocycle or formation of open chain compounds involving the nucleophilic solvent was shown to depend on the nature and the position of the substituent. Photoinduced ring closure into the benzimidazole system, involving a 3-N-phenylamino side chain sequence and a photolytic intermediate of the oxadiazole heterocycle, is also reported.
ChemInform Abstract: Heterocyclic Photorearrangements. Photochemical Behaviour of Some 3,5-Disubstituted 1,2,4-Oxadiazoles in Methanol at 254 nm.
1989
Photochemical behaviour of some 3,5-disubstituted 1,2,4-oxadiazoles in methanol at 254 nm has been investigated. Ring photoisomerization to the 1,3,4-oxadiazole heterocycle or formation of open chain compounds involving the nucleophilic solvent was shown to depend on the nature and the position of the substituent. Photoinduced ring closure into the benzimidazole system, involving a 3-N-phenylamino side chain sequence and a photolytic intermediate of the oxadiazole heterocycle, is also reported.
Antiarrhythmika. I. 2,4-dialkylpyrimido[1,2-a]benzimidazole
1981
Aus der Umsetzung von 2-Aminobenzimidazol (1) mit β-Diketonen (2a-d) gehen die 2,4-Dialkylpyrimido[1,2-a]benzimidazole (3a-d) hervor.
Synthese und narkotische Wirkung von Pyrimido[1,2-a]benzimidazol-2,4-dionen Synthesis and Anesthetic Activity of Pyrimido[1,2-a]benzimidazole-2,4-dio…
1982
Eine betrachtliche Zahl zentral dampfender Verbindungen weist als gemeinsames Strukturelement die Carbonamidgruppierung in offenkettiger oder cyclischer Form auf. Unsere jungsten Untersuchungen uber antibakteriell1 und herbizid2 wirksame Pyrimido[1,2-a]benzimidazole legten nun nahe, in die Entwicklung dieser Strukturklasse die Carbonamidgruppierung einzubeziehen.
Crystal structure of 5-(5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazolin-6-yl)-2-methoxyphenol
2015
In the molecule of the title compound, C21H17N3O2, the 5,6-dihydrobenzimidazo[1,2-c]quinazoline moiety is disordered over two orientations about a pseudo-mirror plane, with a refined occupancy ratio of 0.863 (2):0.137 (2). The dihedral angles formed by the benzimidazole ring system and the benzene ring of the quinazoline group are 14.28 (5) and 4.7 (3)° for the major and minor disorder components, respectively. An intramolecular O—H...O hydrogen bond is present. In the crystal, molecules are linked by O—H...N hydrogen bonds, forming chains running parallel to [10-1].
Multiple, alternative cleavage patterns precede uniform larval morphology during normal development of Dreissena polymorpha (Mollusca, Lamellibranchi…
1995
In this study we reinvestigate the early development of the freshwater mussel Dreissena polymorpha, previously studied by Meisenheimer (1901). The data include video time-lapse recordings of living embryos and bisbenzimide stains of fixed embryos as well as morphometry on fixed, serially-sectioned embryos. We present the cell lineage and cell cycle durations up to the first indication of symmetrization within this embryo. We show that early cell cycles last approximately 1h. A dramatic extension of cell cycle duration and a concomitant asynchrony among the various cell lines was observed starting at the fifth cleavage. Short cell cycles, like those of early blastomeres, were a constant prop…
Retrograde transport of sodium selenite and intracellular injection of micro-ruby: a combined method to describe the morphology of zinc-rich neurones.
2003
Abstract Zinc is found in synaptic vesicles in a large number of glutamatergic systems. Its involvement in neurotransmission and neurological disorders has been suggested. There are methods for tracing these circuits, but they do not fill the dendritic tree. In this study, extracellular selenite injections in vivo were combined with intracellular injection of fluorochromes in fixed tissue to reveal the morphology of these zinc-rich neurones. Intraperitoneal and intracerebral injections of sodium selenite alone or intracerebral injections of selenite combined with bisbenzimide were made in the visual cortex of the rat in order to locate the somata of zinc-rich neurones. After 24 h of retrogr…
AT1-receptor blockade by telmisartan upregulates GTP-cyclohydrolase I and protects eNOS in diabetic rats.
2008
Several enzymatic sources of reactive oxygen species (ROS) were described as potential reasons of eNOS uncoupling in diabetes mellitus. In the present study, we investigated the effects of AT1-receptor blockade with chronic telmisartan (25 mg/kg/day, 6.5 weeks) therapy on expression of the BH4-synthesizing enzyme GTP-cyclohydrolase I (GCH-I), eNOS uncoupling, and endothelial dysfunction in streptozotocin (STZ, 60 mg/kg iv, 7 weeks)-induced diabetes mellitus (type I). Telmisartan therapy did not modify blood glucose and body weight. Aortas from diabetic animals had vascular dysfunction as revealed by isometric tension studies (acetylcholine and nitroglycerin potency). Vascular and cardiac RO…