Search results for "heterocyclic"
showing 10 items of 490 documents
Activation of mGlu3 Receptors Stimulates the Production of GDNF in Striatal Neurons
2009
Metabotropic glutamate (mGlu) receptors have been considered potential targets for the therapy of experimental parkinsonism. One hypothetical advantage associated with the use of mGlu receptor ligands is the lack of the adverse effects typically induced by ionotropic glutamate receptor antagonists, such as sedation, ataxia, and severe learning impairment. Low doses of the mGlu2/3 metabotropic glutamate receptor agonist, LY379268 (0.25-3 mg/kg, i.p.) increased glial cell line-derived neurotrophic factor (GDNF) mRNA and protein levels in the mouse brain, as assessed by in situ hybridization, real-time PCR, immunoblotting, and immunohistochemistry. This increase was prominent in the striatum, …
INHIBITION OF CELLULAR GROWTH AND STEROID 11β-HYDROXYLATION INRAS-TRANSFORMED ADRENOCORTICAL CELLS BY THE FUNGAL TOXINS BETICOLINS
1996
Abstract The proliferation of GM16 and 4CDTras-transformed newborn rat adrenocortical (RTAC) cells and Y1 mouse adrenal tumor cells was inhibited by beticolins, the fungal toxins extracted fromCercospora beticola, at submicromolar concentrations in a dose-dependent manner. Inhibitory concentrations for half the maximum inhibition were 150, 75 and 25 n M for beticolin-1 and 230, 150 and 50 n M for beticolin-2 in GM16, 4CDT and Y1 cells respectively. Beticolins strongly inhibited the production of 11β-hydroxysteroids on the second and third days of treatment in a dose-dependent manner between 0.1 and 1 μ M . Beticolins were shown by confocal microscopy to be localized in cytoplasmic organelle…
Novel platinum(II) complexes with heterociclyc ligands: Synthesis and structural chracterization.
2008
An array of mononuclear complexes of Pt(II) with triazine and (benzimidazolyl)pyridine heterocycles is reported. The mononuclear complexes [PtCl2(Kdptdn)] [dbtdn=5,6- diphenyl-3-(2-pyridyl)-1,2,4-triazine-4’,4’’-disulfonate sodium salt hydrate], [PtCl2(bbp)] [bbp=2,6-bis(2-benzimidazolyl)pyridine] and [PtCl2(H2dpt)]PtCl4 [dpt=5,6-diphenyl-3-(2- pyridyl)-1,2,4-triazine] have been prepared and structurally characterized. Both neutral and ionic complexes are present, with bifunctional Pt(II) moieties, whose size and shape enable them to behave as novel scaffolds for DNA binding.
Application of Molecular Topology for the Prediction of Reaction Yields and Anti-Inflammatory Activity of Heterocyclic Amidine Derivatives
2011
Topological-mathematical models based on multiple linear regression analyses have been built to predict the reaction yields and the anti-inflammatory activity of a set of heterocylic amidine derivatives, synthesized under environmental friendly conditions, using microwave irradiation. Two models with three variables each were selected. The models were validated by cross-validation and randomization tests. The final outcome demonstrates a good agreement between the predicted and experimental results, confirming the robustness of the method. These models also enabled the screening of virtual libraries for new amidine derivatives predicted to show higher values of reaction yields and anti-infl…
Celecoxib for recurrent sclerouveitis after syphilitic panuveitis. A case report
2011
Purpose To report a case of recurrent ocular inflammation after optimal therapy of bilateral syphilitic panuveitis responding to oral celecoxib. Methods A case report was conducted. Results A 76-year-old man presented with painful blurry vision in both eyes. Ocular examination disclosed bilateral panuveitis. Serological testing confirmed blood and cerebrospinal fluid syphilitic involvement. After 2 weeks of intravenous penicillin therapy, recurrent episodic sclerouveitis was observed. Conclusion Ocular inflammation after healing of infectious uveitis is a rare ophthalmic sequela. In an immunocompetent patient, either re-infection or immune uveitis should be evoked. Non-steroidal therapeutic…
STABILITY AND ORGANOCATALYTIC EFFICIENCY OF N-HETEROCYCLIC CARBENES ELECTROGENERATED IN ORGANIC SOLVENTS FROM IMIDAZOLIUM IONIC LIQUIDS
2015
The kinetic of degradation of 1-butyl-3-methylimidazole-2-ylidene (selected as model N-heterocyclic carbene - NHC), generated in organic solvents by cathodic reduction of the parent 1-butyl-3- methylimidazolium salts BMIm-X, was studied by a simple voltammetric analysis. The effect of NHC degradation rate on the efficiency of an organocatalyzed reaction (the synthesis of g-butyrolactone from cinnamaldehyde and trifluoromethylacetophenone) was investigated. The nature of the solvent and of the anion X have a remarkable effect on the stability of the NHC, the bis(trifluoromethylsulfonyl) imide anion being the best for a long lasting carbene (while acetonitrile seems to be the worst solvent). …
Haptotropism in a Nickel Complex with a Neutral, π‐Bridging cyclo‐P4 Ligand Analogous to Cyclobutadiene
2022
The reaction of ( 1 )Ni(η 2 -cod), 2 , incorporating a chelating bis( N -heterocyclic carbene) 1 , with P 4 in pentane yielded the dinuclear complex [( 2 )Ni] 2 (μ 2 ,η 2 :η 2 -P 4 ), 3 , formally featuring a cyclobutadiene-like, neutral, rectangular, π-bridging P 4 -ring. In toluene, the butterfly-shaped complex [( 1 )Ni] 2 (μ 2 ,η 2 :η 2 -P 2 ), 4 , with a formally neutral P 2 -unit was obtained from 2 and either P 4 or 3 . Computational studies showed that a low energy barrier haptotropic rearrangement involving two isomers of the μ 2 ,η 2 :η 2 -P 4 coordination mode and a low energy μ 2 ,η 4 :η 4 -P 4 coordination mode, as previously predicted for related nickel cyclobutadiene complexes…
Extending the Series: Synthesis and Characterization of a Dicationic N-Heterocyclic Selenium Carbene Analogue
2006
The room-temperature reaction between the Dipp2DAB ligand, SnCl2, and SeCl4 results in the quantitative formation of a dicationic N-heterocyclic “carbenoid”. This represents the first example of a chalcogenium dication that mimics the ubiquitous Arduengo-type carbenes; however, the electronic structure is significantly different. peerReviewed
Fluorinated heterocyclic compounds: an assay on the photochemistry of some fluorinated 1-oxa-2-azoles: an expedient route to fluorinated heterocycles
2004
Abstract Photoinduced heterocyclic rearrangements of ON bond-containing azoles have been claimed in the synthesis of target fluorinated heterocyclic compounds. In this context, the photochemical behavior of some fluorinated 1,2,4-oxadiazoles has been investigated. Irradiations of 3-amino-5-perfluoroalkyl-1,2,4-oxadiazoles at λ =313 nm in methanol gave open-chain products arising from a reaction of the nucleophilic solvent with either the first formed ring-photolytic species or with a nitrilimine moiety generated from it. Differently, irradiations in methanol with the presence of triethylamine (TEA) followed competing phototransposition pathways leading to the ring-isomers 2-amino-5-perfluo…
Ground and first excited electronic state interaction of FAD with some β-carboline derivatives
1987
Abstract The spectrophotometric and thermodynamic properties of molecular complexes of flavine adenine dinucleotide (FAD) with some dihydro β-carboline derivatives have been investigated in aqueous solution. The molecular associations have been examined by means of electronic absorption spectra, since in each a new charge-transfer band has been located, and also the variation of the fluorescence emission of FAD on the solutions has been observed. The formation constants for the molecular complexes were determined from absorption data, using the Foster-Hammick-Wardley method. The quenching fluorescence phenomena observed in FAD is related to the concentration of the dihydro β-carboline deriv…