Search results for "Quinoline"
showing 10 items of 391 documents
Synthesis of pyrido[2,1-a]isoquinolin-4-ones and oxazino[2,3-a]isoquinolin-4-ones: New inhibitors of mitochondrial respiratory chain
2013
International audience; Benzo[a]quinolizine is an important heterocyclic framework that can be found in numerous bioactive compounds. The general scheme for the synthesis of these compounds was based on the preparation of the appropriate dihydroisoquinolines by Bischler-Napieralski cyclization with good yields, followed by the Pemberton method to form the oxazinones or pyridones derivatives via acyl-ketene imine cyclocondensation. All the synthesized compounds were assayed in vitro for their ability to inhibit mitochondrial respiratory chain. Most of the tested compounds were able to inhibit the integrated electron transfer chain, measured as NADH oxidation, which includes complexes I, III …
Pyrrolo[3,2-h]quinazolines as Photochemotherapeutic Agents
2011
Heteroanalogues of angelicin, pyrrolo[3,2-h]quinazolines, were synthesized with the aim of obtaining new potent photochemotherapeutic agents. Many derivatives caused a significant decrease in cell proliferation in several human tumor cell lines after irradiation with UVA light (GI(50) =15.2-0.2 μM). Their phototoxicity effected apoptosis in Jurkat cells with the involvement of mitochondria (as determined by the loss of mitochondrial membrane potential and production of reactive oxygen species) and lysosomes. The phototoxicity of these compounds could be explained by lipid peroxidation.
Optimization of a LC method for the enantioseparation of a non-competitive glutamate receptor antagonist, by experimental design methodology
2006
Abstract The aim of this work was to obtain the direct optical resolution of a new glutamate receptor antagonist (( p -chloro)1-aryl-6,7,-dimethoxy-1,2,3,4-tetrahydroisoquinoline, PS3), by liquid chromatography on Chiralcel ® OD column. A response surface methodology (RSM) was employed to optimize the enantiomeric separation of the racemate with the lowest number of experiments; in particular, a face-centred design (FCD) was applied to evaluate the influence of critical parameters on the experimental response. Furthermore, in order to find the best compromise between several responses, a multicriteria decision-making approach, the Derringer's desirability function, was successful to simulta…
Effect of LIF-withdrawal on acetylcholine synthesis in the embryonic stem cell line CGR8 is not mediated by STAT3, PI3Ks or cAMP/PKA pathways.
2015
Acetylcholine (ACh) acts as a local cellular signaling molecule and is widely expressed in nature, including mammalian cells and embryonic stem cells. The murine embryonic stem cell line CGR8 synthesizes and releases substantial amounts of ACh. Particularly during early differentiation - a period associated with multiple alterations in geno-/phenotype functions - synthesis and release of ACh are increased by 10-fold. In murine stem cells second messengers of the STAT-3, PI3K and cAMP/PKA pathways are involved in maintaining self-renewal and pluripotency. The present experiments were designed to test whether blockers of these signaling pathways enhance ACh cell content in the presence of LIF…
Evaluation of the SOS/umu-test post-treatment assay for the detection of genotoxic activities of pure compounds and complex environmental mixtures.
2000
This study presents an evaluation of the SOS/umu-test after introducing an additional dilution and incubation in the post-treatment assay. This treatment reduces the influence of coloured test compounds that otherwise affect the colorimetric determination of the beta-galactosidase activity and the bacterial growth measurement during the testing of complex environmental samples. The post-treatment assay significantly increased the beta-galactosidase activity and consequently the enzyme induction ratios at higher doses of model genotoxins 4-nitroquinoline-N-oxide, N-methyl-N'-nitro-N-nitrosoguanidine, 2-aminoanthracene, benzo(a)pyrene with low or no effect on the sensitivity of the test itsel…
Triazolopyridines 23.1 Synthesis of 5,5'-bi[1,2,3]triazolo[5,1-a]isoquinoline
2004
5,5'-Bi[1,2,3]triazolo[5,1-a]isoquinoline 6 has been synthesised from [1,2,3]triazolo[5,1-a] isoquinoline 5 by four procedures, dimerisation by LDA, Stille and Suzuki self-coupling reactions, and Suzuki cross-coupling reaction. The last is the best. Compound 6 gives 1,1'- bi(acetoxymethyl)-3,3'-biisoquinoline 10 by triazolo ring opening by acetic acid. Abarca Gonzalez, Belen, Belen.Abarca@uv.es ; Ballesteros Campos, Rafael, Rafael.Ballesteros@uv.es ; Gay Roig, Bernat, bergay@alumni.uv.es
DNA damage susceptibility and repair in correlation to calendric age and longevity.
2000
In two mouse strains, SAM P (senescence acceleration prone) and SAM R (senescence acceleration resistant), of different longevities, with a ratio of P/R=1:2), the DNA status in the course of aging has been investigated using the DNA Alkaline Filter Elution (AFE) technique. Six different organs (brain, liver, heart, lung, intestine, and muscle) have been used in each of the four animals of a given age. Earlier it had been shown, that DNA is damaged the more the higher the age of the animal. DNA damage susceptibility, measured after exposure of organ pieces to nitroquinoline-N-oxide (NQO), is also significantly increased at higher ages, while repair, measured of NQO damaged tissue after 3 h i…
NOVEL ANTAGONISTS FOR AN Hsp60-BASED ANTICANCER CHAPERONOTHERAPY
2012
The Heat shock proteins (Hsps) are nowadays considered the most important cell chaperones, which result overexpressed in response to a number of cell stress stimuli.In tumor cells, when Hsp60 accumulates in the cytosol, without mitochondrial release, it exerts an anti-apoptotic effect, by inhibiting pro-caspase-3 (pC3) activation. In this context, our study aims to elucidate the structural details of the interaction between Hsp60 and pC3 and to design novel antagonists able to specifically block this interaction. The analysis of virtual screening results highlights the 4-(3-chloro-4-fluorophenylamino)- 6-[(1H-imidazol-4-yl-methyl)-3-carbonitrile-quinolines of type 1 and the N-{5-[1H-imidazo…
UV Exposure Boosts Transcutaneous Immunization and Improves Tumor Immunity: Cytotoxic T-Cell Priming through the Skin
2010
Immunologic approaches to combat cancer aim at the induction of tumor-reactive immune responses to achieve long-term protection. In this context, we recently developed a transcutaneous immunization (TCI) method using the Toll-like receptor (TLR) 7 agonist imiquimod and a peptide epitope. Application onto intact skin induces potent cytotoxic T lymphocyte (CTL) responses and protection against transplanted tumors. The purpose of this study was to explore the effects of UV irradiation on imiquimod-based TCI. Here we show that skin exposure to low-dose UV light before TCI with imiquimod strongly boosts specific CTL responses leading to memory formation and enhanced tumor protection. Toward the …
CCDC 1407214: Experimental Crystal Structure Determination
2016
Related Article: Alejandro Pascual-Álvarez, Tamara Topala, Francisco Estevan, Francisca Sanz and Gloria Alzuet-Piña|2016|Eur.J.Inorg.Chem.||982|doi:10.1002/ejic.201501469