Sample records for excitotoxin quinolinic acid

  1. Quinolinic acid toxicity on oligodendroglial cells: relevance for multiple sclerosis and therapeutic strategies. (United States)

    Sundaram, Gayathri; Brew, Bruce J; Jones, Simon P; Adams, Seray; Lim, Chai K; Guillemin, Gilles J


    The excitotoxin quinolinic acid, a by-product of the kynurenine pathway, is known to be involved in several neurological diseases including multiple sclerosis (MS). Quinolinic acid levels are elevated in experimental autoimmune encephalomyelitis rodents, the widely used animal model of MS. Our group has also found pathophysiological concentrations of quinolinic acid in MS patients. This led us to investigate the effect of quinolinic acid on oligodendrocytes; the main cell type targeted by the autoimmune response in MS. We have examined the kynurenine pathway (KP) profile of two oligodendrocyte cell lines and show that these cells have a limited threshold to catabolize exogenous quinolinic acid. We further propose and demonstrate two strategies to limit quinolinic acid gliotoxicity: 1) by neutralizing quinolinic acid's effects with anti-quinolinic acid monoclonal antibodies and 2) directly inhibiting quinolinic acid production from activated monocytic cells using specific KP enzyme inhibitors. The outcome of this study provides a new insight into therapeutic strategies for limiting quinolinic acid-induced neurodegeneration, especially in neurological disorders that target oligodendrocytes, such as MS.

  2. Striatal grafts provide sustained protection from kainic and quinolinic acid-induced damage. (United States)

    Tulipan, N; Luo, S Q; Allen, G S; Whetsell, W O


    Grafts of neonatal striatal tissue were placed into the striata of adult rats. When challenged immediately with intrastriatal injections of either kainic or quinolinic acid, excitotoxic damage was prevented. Thirty days later these same graft recipients received another injection of excitotoxin. The intrastriatal grafts continued to mitigate toxin-induced damage. It is hypothesized that the grafted cells not only survive, but that they may continue to elaborate some substance or substances that prevent excitotoxin-induced injury for at least 30 days. Previous investigations indicated that grafts of neonatal striatal tissue can protect the recipient striatum from kainic acid toxicity. In the following study it is demonstrated that such grafts also protect the striatum from quinolinic acid, an endogenous excitotoxin which induces kainate-like neuronal degeneration and has been implicated in the pathogenesis of Huntington's disease. It is postulated that the salutary effect of striatal grafting may be sufficiently long lasting to mitigate a chronic toxic insult. Such grafting may therefore represent a therapy for Huntington's disease and other neurodegenerative disorders in which an endogenous or exogenous toxin has been implicated as the pathogenetic agent.

  3. Synthesis and pharmacology of N-alkylated derivatives of the excitotoxin ibotenic acid

    DEFF Research Database (Denmark)

    Madsen, U; Dumpis, M A; Bräuner-Osborne, Hans


    Three amino-alkylated derivatives of the naturally occurring excitatory amino acid (EAA) receptor agonist ibotenic acid (Ibo) have been synthesized and tested pharmacologically. N-Methyl-Ibo (1a) and N-ethyl-Ibo (1b) were shown to be agonists at NMDA receptors (EC50 = 140 and 320 microM, respecti......Three amino-alkylated derivatives of the naturally occurring excitatory amino acid (EAA) receptor agonist ibotenic acid (Ibo) have been synthesized and tested pharmacologically. N-Methyl-Ibo (1a) and N-ethyl-Ibo (1b) were shown to be agonists at NMDA receptors (EC50 = 140 and 320 micro......-c and the potent NMDA agonist 2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid (AMAA) in order to elucidate the observed structure-activity data....

  4. Quinolinic Acid: Neurotoxin or Oxidative Stress Modulator?

    Directory of Open Access Journals (Sweden)

    Lenka Kubicova


    Full Text Available Quinolinic acid (2,3-pyridinedicarboxylic acid, QUIN is a well-known neurotoxin. Consequently, QUIN could produce reactive oxygen species (ROS. ROS are generated in reactions catalyzed by transition metals, especially iron (Fe. QUIN can form coordination complexes with iron. A combination of differential pulse voltammetry, deoxyribose degradation and Fe(II autoxidation assays was used for explorating ROS formation in redox reactions that are catalyzed by iron in QUIN-Fe complexes. Differential pulse voltammetry showed an anodic shift of the iron redox potential if iron was liganded by QUIN. In the H2O2/FeCl3/ascorbic acid variant of the deoxyribose degradation assay, the dose-response curve was U-shaped. In the FeCl3/ascorbic acid variant, QUIN unambiguously showed antioxidant effects. In the Fe(II autoxidation assay, QUIN decreased the rate of ROS production caused by Fe(II oxidation. Our study confirms that QUIN toxicity may be caused by ROS generation via the Fenton reaction. This, however, applies only for unnaturally high concentrations that were used in attempts to provide support for the neurotoxic effect. In lower concentrations, we show that by liganding iron, QUIN affects the Fe(II/Fe(III ratios that are beneficial to homeostasis. Our results support the notion that redox chemistry can contribute to explaining the hormetic dose-response effects.

  5. Quinolinic Acid, an Endogenous Molecule Combining Excitotoxicity, Oxidative Stress and Other Toxic Mechanisms

    Directory of Open Access Journals (Sweden)

    Verónica Pérez-De La Cruz


    Full Text Available Quinolinic acid (QUIN, an endogenous metabolite of the kynurenine pathway, is involved in several neurological disorders, including Huntington's disease, Alzheimer's disease, schizophrenia, HIV associated dementia (HAD etc. QUIN toxicity involves several mechanisms which trigger various metabolic pathways and transcription factors. The primary mechanism exerted by this excitotoxin in the central nervous system (CNS has been largely related with the overactivation of N-methyl-D-aspartate receptors and increased cytosolic Ca 2+ concentrations, followed by mitochondrial dysfunction, cytochrome c release, ATP exhaustion, free radical formation and oxidative damage. As a result, this toxic pattern is responsible for selective loss of middle size striatal spiny GABAergic neurons and motor alterations in lesioned animals. This toxin has recently gained attention in biomedical research as, in addition to its proven excitotoxic profile, a considerable amount of evidence suggests that oxidative stress and energetic disturbances are major constituents of its toxic pattern in the CNS. Hence, this profile has changed our perception of how QUIN-related disorders combine different toxic mechanisms resulting in brain damage. This review will focus on the description and integration of recent evidence supporting old and suggesting new mechanisms to explain QUIN toxicity.

  6. True Niacin Deficiency in Quinolinic Acid Phosphoribosyltransferase (QPRT) Knockout Mice. (United States)

    Shibata, Katsumi


    Pyridine nucleotide coenzymes (PNCs) are involved in over 500 enzyme reactions. PNCs are biosynthesized from the amino acid L-tryptophan (L-Trp), as well as the vitamin niacin. Hence, "true" niacin-deficient animals cannot be "created" using nutritional techniques. We wanted to establish a truly niacin-deficient model animal using a protocol that did not involve manipulating dietary L-Trp. We generated mice that are missing the quinolinic acid phosphoribosyltransferase (QPRT) gene. QPRT activity was not detected in qprt(-/-)mice. The qprt(+/+), qprt(+/-) or qprt(-/-) mice (8 wk old) were fed a complete diet containing 30 mg nicotinic acid (NiA) and 2.3 g L-Trp/kg diet or an NiA-free diet containing 2.3 g L-Trp/kg diet for 23 d. When qprt(-/-)mice were fed a complete diet, food intake and body weight gain did not differ from those of the qprt(+/+) and the qprt(+/-) mice. On the other hand, in the qprt(-/-) mice fed the NiA-free diet, food intake and body weight were reduced to 60% (pniacin such as blood and liver NAD concentrations were also lower in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice. Urinary excretion of quinolinic acid was greater in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice (pniacin-deficient mice.

  7. Increased quinolinic acid in peripheral mononuclear cells in Alzheimer's dementia. (United States)

    Busse, Mandy; Hettler, Vanessa; Fischer, Victoria; Mawrin, Christian; Hartig, Roland; Dobrowolny, Henrik; Bogerts, Bernhard; Frodl, Thomas; Busse, Stefan


    The role of monocytes and macrophages in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD) is poorly understood. Recently, we have shown that the number of CD14+ monocytes remained constant during healthy aging and in AD patients. Although only little is known about the function of activated macrophages and microglia in AD, one important mechanism involves the expression of quinolinic acid (QUIN), an endogenous N-methyl-D-aspartate glutamate receptor (NMDA-R) agonist which mediates excitotoxicity especially in the hippocampus. We used immunofluorescence stainings of PBMCs to determine the expression of quinolinic acid (QUIN) and the MHC class II molecule HLA-DR in peripheral monocytic cells in 51 healthy volunteers aged 22-87 years and 43 patients with AD at diagnosis (0 weeks) and during the course of rivastigmine treatment at 0.25 year (12 weeks), 0.5 year (30 weeks), 1 year, and 1.5 years. The number of QUIN+ HLA-DR+ cells rises in healthy persons aged 30-40 years compared to persons aged 60-70 years, indicating that this cell population increases with aging. AD patients at diagnosis had an increased frequency of QUIN+, QUIN+ HLA-DR+, and QUIN+ HLA-DR+/HLA-DR+ cells compared to aged-matched controls. These cell populations remained increased in AD for up to one year after initiation of treatment with rivastigmine; no alterations were detected in aged healthy persons. We conclude that the expression of the neurotoxic agent QUIN is increased in peripheral monocytes from AD patients. These cells could enter the brain and contribute to excitotoxicity.

  8. Alteration of kainic acid and quinolinic acid toxicity by neostriatal transplants in vitro. (United States)

    Whetsell, W O; Allen, G S; Tulipan, N B


    Mature (greater than 21 days in vitro) organotypic corticostriatal cultures prepared from newborn rat brain were incubated in either kainic acid (KA) 10(-3) M or quinolinic acid (QUIN) 10(-3) M for up to 48 h. Other identical cultures were similarly incubated immediately after they had received one or two additional explants of neonatal striatal tissue placed beside each corticostriatal culture. The cultures incubated with either KA or QUIN in the presence of the neonatal striatal tissue showed better preservation than cultures incubated with KA or QUIN alone. Results suggest that the neonatal striatal explants or 'transplants' afford some protective effect against the toxicity or either KA or QUIN.

  9. Noncovalent-bonded 1D-3D supramolecular architectures from 2-methylquinoline/quinoline with monocarboxylic acid and dicarboxylic acid (United States)

    Gao, Xingjun; Jin, Shouwen; Jin, Li; Ye, XiangHang; Zheng, Lu; Li, JingWen; Jin, BinPeng; Wang, Daqi


    Studies concentrating on noncovalent weak interactions between the organic base of 2-methylquinoline/quinoline, and carboxylic acid derivatives have led to an increased understanding of the role 2-methylquinoline/quinoline have in binding with carboxylic acids. Here anhydrous multicomponent organic acid-base adducts of 2-methylquinoline/quinoline have been prepared with carboxylic acids that ranged from monocarboxylic acid to dicarboxylic acid such as p-nitrobenzoic acid, (4-chloro-phenoxy)-acetic acid, 4-hydroxy-benzoic acid, 5-bromosalicylic acid, 2,4-dihydroxybenzoic acid, α-ketoglutaric acid, and 4-nitrophthalic acid. The seven crystalline complexes were characterized by X-ray diffraction analysis, IR, m.p., and elemental analysis. These structures adopted the hetero supramolecular synthons. Analysis of the crystal packing of 1-7 suggests that there are Nsbnd H⋯O, Osbnd H⋯N, and Osbnd H⋯O hydrogen bonds (charge assisted or neutral) between the acid and quinoline moieties in the studied compounds. Except the classical hydrogen bonding interactions, the secondary propagating interactions also play important roles in structure extension. These weak interactions combined, these compounds displayed 1D-3D framework structure.

  10. An experimental screen for quinoline/fumaric acid salts and co-crystals

    DEFF Research Database (Denmark)

    Beko, S. L.; Schmidt, M. U.; Bond, A. D.


    An experimental screen has been carried out for salts and co-crystals of quinoline (C9H7N) and fumaric acid (C4H4O4), including solution-based co-crystallisation from a variety of solvents, solvent-assisted and solvent-free co-grinding, and direct co-crystallisation of the starting materials...... using dispersion-corrected density functional theory (DFT-D) calculations suggests that the hypothetical polymorph of the 2 : 1 quinoline/fumaric acid co-crystal derived from the structure of the 2 : 1 6-methylquinoline/fumaric acid co-crystal is ca. 8 kJ mol(-1) less stable than the structure...

  11. A novel one-pot three-step synthesis of 2-(1-Benzofuran-2-yl)quinoline-3-carboxylic acid derivatives


    Gao,Wentao; Zhang,Chaohua; Li,Yang


    A facile and efficient one-pot three-step procedure for the preparation of 2-(1-benzofuran-2-yl)quinoline-3-carboxylic acid derivatives is described, featuring three different synthetic transformations, namely Williamson ether synthesis, hydrolysis of an ester group at the quinoline ring C-3 position, and intramolecular electrophilic cyclization reaction between the aldehyde group of salicylaldehyde and the methylene at the quinoline ring C-2 position. Neste trabalho é descrito um protocol...

  12. (Benzoato-κ2O,O′(quinoline-2-carboxylato-κ2N,O(quinoline-2-carboxylic acid-κ2N,Omanganese(II

    Directory of Open Access Journals (Sweden)

    Nuno D. Martins


    Full Text Available The crystal structure of the title compound, [Mn(C7H5O2(C10H6NO2(C10H7NO2], contains manganese(II ions six-coordinated in a distorted octahedral environment. The equatorial plane is occupied by four O atoms, two from the carboxylate group of the benzoate ion, the other two from carboxylate/carboxyl groups of the quinaldate/quinaldic acid molecules. The axial positions are occupied by the N atoms of the quinoline ring systems. The metal ion lies on a twofold rotation axis that bisects the benzoate ligand; the quinaldate and quinaldic acid ligands are therefore equivalent by symmetry, and the carboxylate/carboxyl groups are disordered. The complexes are joined together by hydrogen bonds between the carboxylate/carboxyl groups of adjacent quinaldate/quinaldic acid molecules, forming zigzag chains that run along the c axis.

  13. Systemic endotoxin increases L-tryptophan, 5-hydroxyindoleacetic acid, 3-hydroxykynurenine and quinolinic acid content of mouse cerebral cortex. (United States)

    Heyes, M P; Quearry, B J; Markey, S P


    Systemic infections and injection of endotoxin are known to increase L-tryptophan release from skeletal muscle and increase systemic L-tryptophan catabolism through the kynurenine pathway. To investigate the effects of systemically administered endotoxin on brain L-tryptophan metabolites. C57BL6/6NCR mice were given an intraperitoneal injection of 10 micrograms of lipopolysaccharide from Salmonella abortus equii and samples of serum and cerebral cortex collected. After 9 h, serum L-tryptophan concentration was decreased by 51%. At 9 h and 24 h, increases in L-tryptophan metabolites in cerebral cortex were: L-tryptophan, 42% and 39%; 5-hydroxyindoleacetic acid, 38% and 67%; 3-hydroxykynurenine, 235% and 381%; and quinolinic acid, 76% and 306%. Cortical quinolinic acid concentration was still elevated at 48 h (88%) and 72 h (79%) after lipopolysaccharide. No significant changes in cortical serotonin concentrations were found at the time points examined. When L-tryptophan (0.37 mmol/kg) was administered systemically to either normal or lipopolysaccharide-treated mice, increases in cortical L-tryptophan, serotonin, 5-hydroxyindoleacetic acid and 3-hydroxykynurenine concentrations were largest in mice treated with both lipopolysaccharide and L-tryptophan. These results suggest that disturbances in L-tryptophan metabolism that follow systemic endotoxin administration extend to the central nervous system. The consequences of these changes in L-tryptophan metabolites remain to be determined.

  14. Involvement of quinolinic acid in the neuropathogenesis of amyotrophic lateral sclerosis. (United States)

    Lee, Jong-Min; Tan, Vanessa; Lovejoy, David; Braidy, Nady; Rowe, Dominic B; Brew, Bruce J; Guillemin, Gilles J


    Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease characterized by a progressive degeneration of central and peripheral motor neurons, leading to the atrophy of voluntary muscles. It has been previously demonstrated that the kynurenine pathway (KP), the major biochemical pathway for tryptophan metabolism, is dysregulated in ALS. In particular, the neuroactive intermediate, quinolinic acid (QUIN) has been shown to accumulate with a concomitant decrease in other neuroprotective and immunomodulatory KP metabolites. Furthermore, multiple biochemical phenomena associated with QUIN cytotoxicity are present in ALS, suggesting that QUIN may play a substantial role in the pathogenesis of ALS. This review highlights the potential roles of QUIN in ALS, and explores KP modulation as a therapeutic candidate in ALS. This article is part of the Special Issue entitled 'The Kynurenine Pathway in Health and Disease'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The phosphorylation status and cytoskeletal remodeling of striatal astrocytes treated with quinolinic acid

    Energy Technology Data Exchange (ETDEWEB)

    Pierozan, Paula; Ferreira, Fernanda; Ortiz de Lima, Bárbara; Gonçalves Fernandes, Carolina [Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90035-003 (Brazil); Totarelli Monteforte, Priscila; Castro Medaglia, Natalia de; Bincoletto, Claudia; Soubhi Smaili, Soraya [Departamento de Farmacologia, Universidade Federal de São Paulo (UNIFESP/EPM), São Paulo, SP (Brazil); Pessoa-Pureur, Regina, E-mail: [Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90035-003 (Brazil)


    Quinolinic acid (QUIN) is a glutamate agonist which markedly enhances the vulnerability of neural cells to excitotoxicity. QUIN is produced from the amino acid tryptophan through the kynurenine pathway (KP). Dysregulation of this pathway is associated with neurodegenerative conditions. In this study we treated striatal astrocytes in culture with QUIN and assayed the endogenous phosphorylating system associated with glial fibrillary acidic protein (GFAP) and vimentin as well as cytoskeletal remodeling. After 24 h incubation with 100 µM QUIN, cells were exposed to {sup 32}P-orthophosphate and/or protein kinase A (PKA), protein kinase dependent of Ca{sup 2+}/calmodulin II (PKCaMII) or protein kinase C (PKC) inhibitors, H89 (20 μM), KN93 (10 μM) and staurosporin (10 nM), respectively. Results showed that hyperphosphorylation was abrogated by PKA and PKC inhibitors but not by the PKCaMII inhibitor. The specific antagonists to ionotropic NMDA and non-NMDA (50 µM DL-AP5 and CNQX, respectively) glutamate receptors as well as to metabotropic glutamate receptor (mGLUR; 50 µM MCPG), mGLUR1 (100 µM MPEP) and mGLUR5 (10 µM 4C3HPG) prevented the hyperphosphorylation provoked by QUIN. Also, intra and extracellular Ca{sup 2+} quelators (1 mM EGTA; 10 µM BAPTA-AM, respectively) prevented QUIN-mediated effect, while Ca{sup 2+} influx through voltage-dependent Ca{sup 2+} channel type L (L-VDCC) (blocker: 10 µM verapamil) is not implicated in this effect. Morphological analysis showed dramatically altered actin cytoskeleton with concomitant change of morphology to fusiform and/or flattened cells with retracted cytoplasm and disruption of the GFAP meshwork, supporting misregulation of actin cytoskeleton. Both hyperphosphorylation and cytoskeletal remodeling were reversed 24 h after QUIN removal. Astrocytes are highly plastic cells and the vulnerability of astrocyte cytoskeleton may have important implications for understanding the neurotoxicity of QUIN in neurodegenerative

  16. AAV-BDNF mediated attenuation of quinolinic acid-induced neuropathology and motor function impairment. (United States)

    Kells, A P; Henry, R A; Connor, B


    Maintenance and plasticity of striatal neurons is dependent on brain-derived neurotrophic factor (BDNF), which is depleted in the Huntington's disease striatum due to reduced expression and disrupted corticostriatal transportation. In this study we demonstrate that overexpression of BDNF in the striatum attenuates motor impairment and reduces the extent of striatal damage following quinolinic acid lesioning. Transfer of the BDNF gene to striatal neurons using serotype 1/2 adeno-associated viral vectors enhanced BDNF protein levels in the striatum, but induced weight loss and seizure activity following long-term high-level expression. Lower concentration BDNF expression supported striatal neurons against excitotoxic insult, as demonstrated by enhanced krox-24 immunopositive neuron survival, reduction of striatal atrophy and maintenance of the patch/matrix organization. Additionally, BDNF expression attenuated motor impairment in the forelimb use cylinder test, sensorimotor neglect in the corridor food selection task and reversed apomorphine-induced rotational behaviour. Direct correlations were shown for the first time between BDNF-mediated attenuation of behavioural impairment and the integrity of the globus pallidus, seemingly independent from the severity of striatal lesioning. These results demonstrate that BDNF holds considerable therapeutic potential for alleviating both neuropathological and motor function deficits in the Huntington's disease brain, and the critical role of pallidal neurons in facilitating motor performance.

  17. Investigation of prototypal MOFs consisting of polyhedral cages with accessible Lewis-acid sites for quinoline synthesis. (United States)

    Gao, Wen-Yang; Leng, Kunyue; Cash, Lindsay; Chrzanowski, Matthew; Stackhouse, Chavis A; Sun, Yinyong; Ma, Shengqian


    A series of prototypal metal-organic frameworks (MOFs) consisting of polyhedral cages with accessible Lewis-acid sites, have been systematically investigated for Friedländer annulation reaction, a straightforward approach to synthesizing quinoline and its derivatives. Amongst them MMCF-2 demonstrates significantly enhanced catalytic activity compared with the benchmark MOFs, HKUST-1 and MOF-505, as a result of a high-density of accessible Cu(II) Lewis acid sites and large window size in the cuboctahedral cage-based nanoreactor of MMCF-2.

  18. Antiperoxidative and antiinflammatory effect of Sida cordifolia Linn. on quinolinic acid induced neurotoxicity. (United States)

    Swathy, S S; Panicker, Seema; Nithya, R S; Anuja, M M; Rejitha, S; Indira, M


    Sida cordifolia is a plant belonging to the Malvaceae family used in many ayurvedic preparations. This study aimed at assessing the effects of ethanolic extract of Sida cordifolia root on quinolinic acid (QUIN) induced neurotoxicity and to compare its effect with the standard drug deprenyl in rat brain. Rats were divided into six groups: (1) control group (2) QUIN (55 microg/100 g bwt/day) (3) 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (4) Deprenyl (100 microg/100 g bwt/day) (5) QUIN (55 microg/100 g bwt/day) + 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (6) QUIN (55 microg/100 g bwt/day) + Deprenyl (100 microg/100 g bwt/day). At the end of the experimental period a status of lipid peroxidation products, protein peroxidation product, activities of the scavenging enzymes and the activities of the inflammatory markers were analyzed. Results revealed that the lipid peroxidation products decreased and the activities of the scavenging enzymes increased significantly in the brain of the plant extract treated group, deprenyl treated group and also in the coadminstered groups. The activities of markers of inflammatory responses such as cyclooxygenase and lipoxygenase were found to be significantly increased in the QUIN treated rats and this was decreased upon the administration of plant extract and deprenyl. In short, the study revealed that 50% ethanolic extract of Sida cordifolia has got potent antioxidant and antiinflammatory activity and the activity is comparable with the standard drug deprenyl.

  19. C8-Selective Acylation of Quinoline N-Oxides with α-Oxocarboxylic Acids via Palladium-Catalyzed Regioselective C-H Bond Activation. (United States)

    Chen, Xiaopei; Cui, Xiuling; Wu, Yangjie


    A facile and efficient protocol for palladium-catalyzed C8-selective acylation of quinoline N-oxides with α-oxocarboxylic acids has been developed. In this approach, N-oxide was utilized as a stepping stone for the remote C-H functionalization. The reactions proceeded efficiently under mild reaction conditions with excellent regioselectivity and broad functional group tolerance.

  20. Central Nervous System Infection with Borna Disease Virus Causes Kynurenine Pathway Dysregulation and Neurotoxic Quinolinic Acid Production. (United States)

    Formisano, Simone; Hornig, Mady; Yaddanapudi, Kavitha; Vasishtha, Mansi; Parsons, Loren H; Briese, Thomas; Lipkin, W Ian; Williams, Brent L


    Central nervous system infection of neonatal and adult rats with Borna disease virus (BDV) results in neuronal destruction and behavioral abnormalities with differential immune-mediated involvement. Neuroactive metabolites generated from the kynurenine pathway of tryptophan degradation have been implicated in several human neurodegenerative disorders. Here, we report that brain expression of key enzymes in the kynurenine pathway are significantly, but differentially, altered in neonatal and adult rats with BDV infection. Gene expression analysis of rat brains following neonatal infection showed increased expression of kynurenine amino transferase II (KATII) and kynurenine-3-monooxygenase (KMO) enzymes. Additionally, indoleamine 2,3-dioxygenase (IDO) expression was only modestly increased in a brain region- and time-dependent manner in neonatally infected rats; however, its expression was highly increased in adult infected rats. The most dramatic impact on gene expression was seen for KMO, whose activity promotes the production of neurotoxic quinolinic acid. KMO expression was persistently elevated in brain regions of both newborn and adult BDV-infected rats, with increases reaching up to 86-fold. KMO protein levels were increased in neonatally infected rats and colocalized with neurons, the primary target cells of BDV infection. Furthermore, quinolinic acid was elevated in neonatally infected rat brains. We further demonstrate increased expression of KATII and KMO, but not IDO, in vitro in BDV-infected C6 astroglioma cells. Our results suggest that BDV directly impacts the kynurenine pathway, an effect that may be exacerbated by inflammatory responses in immunocompetent hosts. Thus, experimental models of BDV infection may provide new tools for discriminating virus-mediated from immune-mediated impacts on the kynurenine pathway and their relative contribution to neurodegeneration.IMPORTANCE BDV causes persistent, noncytopathic infection in vitro yet still elicits

  1. Temperature-/solvent-dependent low-dimensional compounds based on quinoline-2,3-dicarboxylic acid: structures and fluorescent properties. (United States)

    Wang, Ming-Fang; Hong, Xu-Jia; Zhan, Qing-Guang; Jin, Hong-Guang; Liu, Yi-Ting; Zheng, Zhi-Peng; Xu, Shi-Hai; Cai, Yue-Peng


    A series of 0-D, 1-D, and 2-D metal-organic compounds through reactions of quinoline-2,3-dicarboxylic acid (2,3-H(2)qldc) with transition metal salts MCl(2), namely, M(2,3-Hqldc)(2)(H(2)O)(2) (M = Co(1), Zn(4) and Cd(7)), [M(3-qlc)(2)(H(2)O)(2)](n) (M = Co(2), Zn(5) and Cd(8)), M(2-qldc-3-OCH(3))(2)(CH(3)OH)(2) (M = Co(3) and Zn(6)) and [Cd(2,3-qldc-OCH(3))(μ(2)-Cl)](2n) (9) (where, 3-Hqlc = quinoline-3-carboxylic acid and 2-qldc-3-OCH(3) = 3-(methoxycarbonyl)quinoline-2-carboxylic acid), were synthesized and characterized by elemental analysis, IR, thermogravimetric analysis (TG), and single-crystal X-ray diffraction. When the temperature ranged from room temperature to 70 °C, three isomorphous mononuclear complexes 1, 4 and 7 were obtained in H(2)O/H(2)O + CH(3)OH. As the temperature rose further to above 90 °C, due to the decomposition of 2-position carboxyl group in ligand 2,3-H(2)qldc, the same reactions, respectively, produced three isomorphous 2-D layer-like structures 2, 5 and 8 with 4(4) topology in water. By contrast, when the mixed solvent of H(2)O + CH(3)OH at a 1 : 1 ratio (v/v) was applied, the three above-mentioned reactions respectively gave compounds 3, 6 and 9 with the 3-position esterification of 2,3-H(2)qldc. Compounds 3 and 6 are mononuclear and isomorphous, while complex 9 has a 1-D double-stranded chain-like structure connected by two μ(2)-Cl bridges. Obviously, these results reveal that the reaction temperature and solvent play a critical role in structural direction of these low-dimensional compounds. Meanwhile, the photoluminescent property of the selected compounds is also investigated.

  2. Elevated brain 3-hydroxykynurenine and quinolinate levels in Huntington disease mice. (United States)

    Guidetti, Paolo; Bates, Gillian P; Graham, Rona K; Hayden, Michael R; Leavitt, Blair R; MacDonald, Marcy E; Slow, Elizabeth J; Wheeler, Vanessa C; Woodman, Ben; Schwarcz, Robert


    The brain levels of the endogenous excitotoxin quinolinic acid (QUIN) and its bioprecursor, the free radical generator 3-hydroxykynurenine (3-HK), are elevated in early stage Huntington disease (HD). We now examined the status of these metabolites in three mouse models of HD. In R6/2 mice, 3-HK levels were significantly and selectively elevated in the striatum, cortex and cerebellum starting at 4 weeks of age. In contrast, both 3-HK and QUIN levels were increased in the striatum and cortex of the full-length HD models, beginning at 8 months (YAC128) and 15 months (Hdh(Q92) and Hdh(Q111)), respectively. No changes were seen in 13-month-old shortstop mice, which show no signs of motor or cognitive dysfunction or selective neuropathology. These results demonstrate both important parallels and intriguing differences in the progressive neurochemical changes in these HD mouse models and support the hypothesis that QUIN may play a role in the striatal and cortical neurodegeneration of HD.

  3. Treadmill exercise improves short-term memory by enhancing hippocampal cell proliferation in quinolinic acid-induced Huntington?s disease rats


    Kim, You-Mi; Ji, Eun-Sang; Kim, Sang-Hoon; Kim, Tae-Woon; Ko, Il-Gyu; Jin, Jun-Jang; Kim, Chang-Ju; Kim, Tae-Wook; Kim, Dong-Hee


    Huntington?s disease (HD) is an inherited genetic disorder, characterized by cognitive dysfunction and abnormal body movements called chorea. Quinolinic acid (QA) is an endogenous metabolite of tryptophan in the kynurenine pathway. QA-induced alterations are similar to the symptoms of HD patients. Physical exercise has beneficial effects on the brain functions. Exercise increases production of neurotrophic factors in the brain and improves learning ability and memory function. In the present ...

  4. Centella asiatica and Its Fractions Reduces Lipid Peroxidation Induced by Quinolinic Acid and Sodium Nitroprusside in Rat Brain Regions. (United States)

    Marques, Naiani Ferreira; Stefanello, Sílvio Terra; Froeder, Amanda L F; Busanello, Alcindo; Boligon, Aline Augusti; Athayde, Margareth Linde; Soares, Félix A A; Fachinetto, Roselei


    Oxidative stress has been implicated in several pathologies including neurological disorders. Centella asiatica is a popular medicinal plant which has long been used to treat neurological disturbances in Ayurvedic medicine. In the present study, we quantified of compounds by high performance liquid chromatography (HPLC) and examined the phenolic content of infusion, ethyl acetate, n-butanolic and dichloromethane fractions. Furthermore, we analyzed the ability of the extracts from C. asiatica to scavenge the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) radical as well as total antioxidant activity through the reduction of molybdenum (VI) (Mo(6+)) to molybdenum (V) (Mo(5+)). Finally, we examined the antioxidant effect of extracts against oxidant agents, quinolinic acid (QA) and sodium nitroprusside (SNP), on homogenates of different brain regions (cerebral cortex, striatum and hippocampus). The HPLC analysis revealed that flavonoids, triterpene glycoside, tannins, phenolic acids were present in the extracts of C. asiatica and also the phenolic content assay demonstrated that ethyl acetate fraction is rich in these compounds. Besides, the ethyl acetate fraction presented the highest antioxidant effect by decreasing the lipid peroxidation in brain regions induced by QA. On the other hand, when the pro-oxidant agent was SNP, the potency of infusion, ethyl acetate and dichloromethane fractions was equivalent. Ethyl acetate fraction from C. asiatica also protected against thiol oxidation induced by SNP and QA. Thus, the therapeutic potential of C. asiatica in neurological diseases could be associated to its antioxidant activity.

  5. Development of a liquid chromatography-mass spectrometry method for the determination of the neurotoxic quinolinic acid in human serum. (United States)

    Meinitzer, Andreas; Tomaschitz, Andreas; Pilz, Stefan; Truber, Manfred; Zechner, Gabriele; Gaksch, Martin; Prietl, Barbara; Treiber, Gerlies; Schwarz, Michaela; Baranyi, Andreas


    Quinolinic acid (QA) is thought to be one of the most important metabolites of the kynurenine pathway with the highest biological activity in apoptotic responses and neurodegenerative diseases. The determination of QA might be of clinical relevance in different patient groups, but currently, only a few laborious methods with high levels of sample volume consumption are available. We developed and validated a simple liquid chromatography-tandem mass spectrometric (LC-tandem MS) method for the determination of QA in human serum with low sample volume requirements. The presented method provides high sample throughput with 25 μL aliquots and works in the positive electrospray ionization (ESI) mode. A commercially available QA-d3 was used as internal standard. Specific transitions for QA and QA-d3 were m/z 280→m/z 78 and m/z 283→m/z 81, respectively. The intra- and inter-assay coefficients of variation (CVs) were all below 10%. Applying this method, in 50 healthy humans a mean serum concentration of QA of 350±167 nmol/L (mean±SD) was determined. The described method is suitable for large clinical trials, which is of potential clinical importance to elucidate the function of QA and its relationship to different disease patterns and may be applicable for clinical laboratory routine. Copyright © 2014 Elsevier B.V. All rights reserved.


    Bezzina, G.; Cheung, T.H.C.; Asgari, K.; Hampson, C.L.; Body, S.; Bradshaw, C.M.; Szabadi, E.; Deakin, J.F.W.; Anderson, I.M.


    Rationale There is evidence that lesions of the nucleus accumbens core (AcbC) promote preference for smaller earlier reinforcers over larger delayed reinforcers in inter-temporal choice paradigms. It is not known whether this reflects an effect of the lesion on the rate of delay discounting, on sensitivity to reinforcer magnitude, or both. Aim We examined the effect of AcbC lesions on inter-temporal choice using a quantitative method that allows effects on delay discounting to be distinguished from effects on sensitivity to reinforcer size. Method 16 rats received bilateral quinolinic acid-induced lesions of the AcbC; 14 received sham lesions. They were trained under a discrete-trials progressive delay schedule to press two levers (A and B) for a sucrose solution. Responses on A delivered 50 μl of the solution after a delay dA; responses on B delivered 100 μl after dB. dB increased across blocks of trials, while dA was manipulated across phases of the experiment. Indifference delay dB(50) (value of dB corresponding to 50% choice of B) was estimated in each phase, and linear indifference functions (dB(50) vs. dA) derived. Results dB(50) increased linearly with dA (r2>0.95 in each group). The intercept of the indifference function was lower in the lesioned than the sham-lesioned group; slope did not differ between groups. The lesioned rats had extensive neuronal loss in the AcbC. Conclusions The results confirm that lesions of the AcbC promote preference for smaller, earlier reinforcers and suggest that this reflects an effect of the lesion on the rate of delay discounting. PMID:17659381

  7. Effects of quinolinic acid-induced lesions of the nucleus accumbens core on inter-temporal choice: a quantitative analysis. (United States)

    Bezzina, G; Cheung, T H C; Asgari, K; Hampson, C L; Body, S; Bradshaw, C M; Szabadi, E; Deakin, J F W; Anderson, I M


    There is evidence that lesions of the nucleus accumbens core (AcbC) promote preference for smaller earlier reinforcers over larger delayed reinforcers in inter-temporal choice paradigms. It is not known whether this reflects an effect of the lesion on the rate of delay discounting, on sensitivity to reinforcer magnitude, or both. We examined the effect of AcbC lesions on inter-temporal choice using a quantitative method that allows effects on delay discounting to be distinguished from effects on sensitivity to reinforcer size. Sixteen rats received bilateral quinolinic acid-induced lesions of the AcbC; 14 received sham lesions. They were trained under a discrete-trials progressive delay schedule to press two levers (A and B) for a sucrose solution. Responses on A delivered 50 microl of the solution after a delay d(A); responses on B delivered 100 microl after d(B). d(B) increased across blocks of trials, while d(A) was manipulated across phases of the experiment. Indifference delay d(B(50)) (value of d(B) corresponding to 50% choice of B) was estimated in each phase, and linear indifference functions (d(B(50)) vs d(A)) derived. d(B(50)) increased linearly with d(A) (r(2) > 0.95 in each group). The intercept of the indifference function was lower in the lesioned than the sham-lesioned group; slope did not differ between groups. The lesioned rats had extensive neuronal loss in the AcbC. The results confirm that lesions of the AcbC promote preference for smaller, earlier reinforcers and suggest that this reflects an effect of the lesion on the rate of delay discounting.

  8. AAV-mediated delivery of BDNF augments neurogenesis in the normal and quinolinic acid-lesioned adult rat brain. (United States)

    Henry, Rebecca A; Hughes, Stephanie M; Connor, Bronwen


    Brain-derived neurotrophic factor (BDNF) plays a major role in regulating the survival and fate of progenitor cells in the adult brain. In order to extend previous observations in the normal adult brain and advance our knowledge regarding the effect of BDNF on neurogenesis in the injured brain, this study directly compared the effect of BDNF on basal and injury-induced neurogenesis in relation to progenitor cell distribution and levels of neuronal differentiation and survival. BDNF was overexpressed in the subventricular zone (SVZ) via recombinant adeno-associated virus (AAV(1/2)) delivery, and newly generated cells were identified using bromodeoxyuridine (BrdU) labelling. Selective striatal cell loss was induced in a subgroup of rats by unilateral striatal injection of quinolinic acid (QA) 21 days after AAV(1/2) injection. In the normal brain, BDNF overexpression significantly increased BrdU-positive cell numbers in the rostral migratory stream, indicating enhanced progenitor cell migration. Following QA lesioning, we observed a reduction in BrdU immunoreactivity in the SVZ. Overexpression of BDNF restored BrdU-positive cell numbers in the QA-lesioned SVZ to that observed in the normal brain. Most significantly, BDNF enhanced the recruitment of progenitor cells to the QA-lesioned striatum and promoted neuronal differentiation in both the normal and QA-lesioned striatum. Our findings indicate that BDNF augments the recruitment, neuronal differentiation and survival of progenitor cells in both neurogenic and non-neurogenic regions of the normal or QA-lesioned brain. Enhanced expression of BDNF may therefore be a viable strategy for augmenting neurogenesis from endogenous progenitor cells.

  9. Development and validation of a differential pulse polarographic method for quinolinic acid determination in human plasma and urine after solid-phase extraction: a chemometric approach. (United States)

    Furlanetto, S; Pinzauti, S; La Porta, E; Chiarugi, A; Mura, P; Orlandini, S


    A chemometric approach was applied for determining quinolinic acid in human plasma by differential pulse polarography after solid phase extraction. A fractional factorial design was used to examine the significant experimental variables for the peak height maximization. A Doehlert design, which allowed a sequential response surface methodology to be performed, was applied to the variables scan rate and drop size. The results indicated that the scan rate had the greatest effect on the response peak height. The linear range was extended from 8.52 x 10(-8) to 1.34 x 10(-5) M and the limit of detection was 2.9 x 10(-8) M. The validation process consisted of a pre-validation study followed by the main validation in the plasma matrix. The robustness and the intermediate precision were evaluated by means of experimental design. A 3(4)//9 screening symmetric matrix and a central composite design were used to optimize the solid phase extraction procedure of the analyte from human plasma using anion exchange cartridges. The goal was to select the best retention, wash and elution solvents and their volumes in order to maximize the extraction efficiency using as the response the polarographic peak height. An extraction efficiency of 90% was found. The method was also applied to the determination of quinolinic acid in urine and the mean concentration in human plasma and urine, was found to be 3.7 x 10(-7) and 4.9 x 10(-5) M respectively.

  10. Toxic synergism between quinolinic acid and organic acids accumulating in glutaric acidemia type I and in disorders of propionate metabolism in rat brain synaptosomes: Relevance for metabolic acidemias. (United States)

    Colín-González, A L; Paz-Loyola, A L; Serratos, I; Seminotti, B; Ribeiro, C A J; Leipnitz, G; Souza, D O; Wajner, M; Santamaría, A


    The brain of children affected by organic acidemias develop acute neurodegeneration linked to accumulation of endogenous toxic metabolites like glutaric (GA), 3-hydroxyglutaric (3-OHGA), methylmalonic (MMA) and propionic (PA) acids. Excitotoxic and oxidative events are involved in the toxic patterns elicited by these organic acids, although their single actions cannot explain the extent of brain damage observed in organic acidemias. The characterization of co-adjuvant factors involved in the magnification of early toxic processes evoked by these metabolites is essential to infer their actions in the human brain. Alterations in the kynurenine pathway (KP) - a metabolic route devoted to degrade tryptophan to form NAD(+) - produce increased levels of the excitotoxic metabolite quinolinic acid (QUIN), which has been involved in neurodegenerative disorders. Herein we investigated the effects of subtoxic concentrations of GA, 3-OHGA, MMA and PA, either alone or in combination with QUIN, on early toxic endpoints in rat brain synaptosomes. To establish specific mechanisms, we pre-incubated synaptosomes with different protective agents, including the endogenous N-methyl-d-aspartate (NMDA) receptor antagonist kynurenic acid (KA), the antioxidant S-allylcysteine (SAC) and the nitric oxide synthase (NOS) inhibitor nitro-l-arginine methyl ester (l-NAME). While the incubation of synaptosomes with toxic metabolites at subtoxic concentrations produced no effects, their co-incubation (QUIN+GA, +3-OHGA, +MMA or +PA) decreased the mitochondrial function and increased reactive oxygen species (ROS) formation and lipid peroxidation. For all cases, this effect was partially prevented by KA and l-NAME, and completely avoided by SAC. These findings suggest that early damaging events elicited by organic acids involved in metabolic acidemias can be magnified by toxic synergism with QUIN, and this process is mostly mediated by oxidative stress, and in a lesser extent by excitotoxicity and

  11. Solventless Synthesis of Quinoline Derivatives: Acceleration of ...

    African Journals Online (AJOL)


    of poly-substituted quinolines.12–17 These reactions are generally carried out in the presence of a base or by heating a mixture of the reactants at high temperatures in the absence of catalyst. Recently, several Brönsted acid and Lewis acid have been utilized for this conversion.15,18–31 Most of the synthetic methods.

  12. The effect of minocycline on indolamine 2, 3 dioxygenase expression and the levels of kynurenic acid and quinolinic acid in LPS-activated primary rat microglia. (United States)

    Bahrami, Zahra; Firouzi, Masoumeh; Hashemi-Monfared, Afrouzeh; Zahednasab, Hamid; Harirchian, Mohammad Hossein


    Microglia are one of the most important neural cells in the central nervous system (CNS) which account for 10-15% of all cells found in the brain. A vast majority of studies indicate that microglia play a pivotal role in protection and damage of the CNS. It has been shown that microglia are mainly scavenger cells but also produce a barrage of factors that are involved in tissue repair and neural regeneration. Several lines of evidence indicate that unregulated activation of microglia in response to either endogenous or exogenous insults results in the production of toxic factors that propagate neuronal injury. Studies demonstrated that the activated microglia secret the excessive amounts of quinolinic acid (QA) and kynurenic acid (KYNA) which are highly toxic for the neuronal cells. In line with this, indolamine 2, 3 dioxygenase (IDO), an enzyme producing KYNA and QA has been shown to be elevated during the inflammation in microglia. In this study, we established primary microglial cell cultures obtained from cerebral cortices of 1-day neonatal Wistar rats. Minocycline (20-60 µM) or its vehicle was added to the culture media 60 min prior to 48 h incubation with lipopolysaccharide (LPS; 10 ng/mL). Using a specific process of adhesion and shaking of the cultured glial cells, a purified culture of approximately 94% enriched microglia was obtained and then, corroborated by immunocytochemistry (ICC). The cell viability after minocycline treatments was assessed using the MTT colorimetric assay. The expression of IDO was evaluated using qPCR. The levels of KYNA and QA were determined using enzyme-linked immunosorbent assay (ELISA). The results showed that minocycline significantly decreased the levels of both KYNA and QA in glia cells exposed to LPS. Moreover, minocycline decreased the expression of IDO in treated LPS-induced microglia. It seems that minocycline has a potent ability to oppress the inflammatory process via the decrease in production of IDO

  13. Studies on the potential neurotoxic and convulsant effects of increased blood levels of quinolinic acid in rats with altered blood-brain barrier permeability

    Energy Technology Data Exchange (ETDEWEB)

    Vezzani, A.; Stasi, M.A.; Wu, H.Q.; Castiglioni, M.; Weckermann, B.; Samanin, R. (Istituto di Ricerche Farmacologiche Mario Negri, Milano (Italy))


    Intravenous injection of 450 mg/kg quinolinic acid (Quin), an endogenous kynurenine metabolite with excitotoxic properties, induced only minor electroencephalographic (EEG) modifications and no neurotoxicity in rats with a mature blood-brain barrier (BBB). BBB permeability was altered in rats by focal unilateral irradiation of the cortex (7 mm in diameter and 5 mm in depth) with protons (60 Gy, 9 Gy/min). Three days after irradiation, Evans blue dye staining showed BBB breakdown in the dorsal hippocampus of the irradiated hemisphere. No neurotoxic or convulsant effects were observed as a consequence of the radiation itself. When BBB-lesioned rats were challenged with 225 mg/kg Quin iv, epileptiform activity was observed on EEG analysis. Tonic-clonic seizures were induced by 225-450 mg/kg Quin. Light microscopic analysis showed a dose-related excitotoxic type of lesion restricted to the hippocampus ipsilateral to the irradiated side. Neuro-degeneration was prevented by local injection of 120 nmol D(-)2-amino-7-phosphonoheptanoic acid, a selective N-methyl-D-aspartate receptor antagonist. No lesions or EEG or behavioral modifications occurred after 450 mg/kg nicotinic acid, an inactive analog of Quin. The potential neurotoxic and convulsant effects of increased blood levels of Quin under conditions of altered BBB permeability are discussed.

  14. Wet oxidation of quinoline

    DEFF Research Database (Denmark)

    Thomsen, A.B.; Kilen, H.H.


    The influence of oxygen pressure (0.4 and 2 MPa). reaction time (30 and 60 min) and temperature (260 and 280 degrees C) on the wet oxidation of quinoline has been studied. The dominant parameters for the decomposition of quinoline were oxygen pressure and reaction temperature. whereas the reaction...... if low oxygen pressure or long reaction times were used. The reaction products derived from the experiment in which quinoline was mostly decomposed were studied with respect to biological degradation. The results showed that these products were highly digestible under activated sludge treatment....... The combined wet oxidation and biological treatment of reaction products resulted in 91% oxidation of the parent compound to CO2 and water. Following combined wet oxidation and biological treatment the sample showed low toxicity towards Nitrosomonas and no toxicity towards Nitrobacter. (C) 1998 Elsevier...

  15. AAV-mediated expression of Bcl-xL or XIAP fails to induce neuronal resistance against quinolinic acid-induced striatal lesioning. (United States)

    Kells, Adrian P; Connor, Bronwen


    Apoptotic mechanisms have been proposed to contribute to the selective loss of medium spiny striatal projection neurons in Huntington's disease (HD). This raises the question as to whether enhancing the expression of anti-apoptotic factors in vulnerable striatal projection neurons can reduce their susceptibility to neurotoxic processes occurring in the HD brain. In this study AAV 1/2 vectors encoding either the anti-apoptotic factor Bcl-xL or XIAP were used to transduce striatal neurons prior to an intrastriatal injection of the excitotoxic glutamate analogue quinolinic acid (QA). AAV 1/2 vector treated rats were observed in behavioural tests undertaken to assess whether anti-apoptotic factor expression provided amelioration of motor function impairment following unilateral QA-induced striatal lesioning. AAV-XIAP treated rats displayed complete amelioration of an ipsilateral forelimb use bias relative to control animals. However, neither AAV-XIAP nor AAV-Bcl-xL treated rats demonstrated an improvement in sensorimotor neglect compared to control animals. Furthermore, we did not observe a significant reduction of QA-induced pathology in assessed neuronal populations of the basal ganglia. These results indicate that sole enhancement of XIAP or Bcl-xL is not sufficient to counteract QA-induced excitotoxic insult of striatal neurons.

  16. Minocycline modulates neuroprotective effect of hesperidin against quinolinic acid induced Huntington's disease like symptoms in rats: behavioral, biochemical, cellular and histological evidences. (United States)

    Kumar, Anil; Chaudhary, Tanya; Mishra, Jitendriya


    Emerging evidences indicate hesperidin, a citrus flavanone, attenuates neurodegenerative processes and related complications. Besides its anti-oxidant properties, the other probable mechanisms which underpin its neuroprotective potential are still not clear. In light of emerging role of flavonoids in modulating oxidative stress and neuro-inflammation, the study has been designed to explore the possible neuroprotective effect of hesperidin and its combination with minocycline (microglial inhibitor), against quinolinic acid (QA) induced Huntington's disease (HD) like symptoms in rats. Unilateral intrastriatal administration of QA (300 nmol/4 µl) significantly reduced body weight, impaired behavior (locomotor activity, beam balance and memory performance), caused oxidative damage (increased lipid peroxidation, nitrite concentration, depleted super oxide dismutase and reduced glutathione), demonstrated mitochondrial dysfunction (decreased Complex-I, II, III, and IV activities), increased striatal lesion volume and altered the levels of TNF-α, caspase-3 as well as BDNF expression, as compared to sham group. Meanwhile, chronic hesperidin (100mg/kg, p.o.) and minocycline (25mg/kg, p.o.) treatment for 21 days significantly attenuated the behavioral, biochemical and cellular alterations as compared to QA treated (control) animals, whereas hesperidin (50mg/kg, p.o.) treatment was found to be non-significant. However, treatment of hesperidin (50mg/kg) in combination with minocycline (25mg/kg) potentiated their neuroprotective effect, which was significant as compared to their effects per se in QA treated animals. Taken altogether, the results of the present study suggest a possible interplay of microglial modulation and anti-oxidant effect in neuroprotective potential of hesperidin against QA induced HD like symptoms in rats. © 2013 Published by Elsevier B.V.

  17. Severe depression is associated with increased microglial quinolinic acid in subregions of the anterior cingulate gyrus: Evidence for an immune-modulated glutamatergic neurotransmission?

    Directory of Open Access Journals (Sweden)

    Mawrin Christian


    Full Text Available Abstract Background Immune dysfunction, including monocytosis and increased blood levels of interleukin-1, interleukin-6 and tumour necrosis factor α has been observed during acute episodes of major depression. These peripheral immune processes may be accompanied by microglial activation in subregions of the anterior cingulate cortex where depression-associated alterations of glutamatergic neurotransmission have been described. Methods Microglial immunoreactivity of the N-methyl-D-aspartate (NMDA glutamate receptor agonist quinolinic acid (QUIN in the subgenual anterior cingulate cortex (sACC, anterior midcingulate cortex (aMCC and pregenual anterior cingulate cortex (pACC of 12 acutely depressed suicidal patients (major depressive disorder/MDD, n = 7; bipolar disorder/BD, n = 5 was analyzed using immunohistochemistry and compared with its expression in 10 healthy control subjects. Results Depressed patients had a significantly increased density of QUIN-positive cells in the sACC (P = 0.003 and the aMCC (P = 0.015 compared to controls. In contrast, counts of QUIN-positive cells in the pACC did not differ between the groups (P = 0.558. Post-hoc tests showed that significant findings were attributed to MDD and were absent in BD. Conclusions These results add a novel link to the immune hypothesis of depression by providing evidence for an upregulation of microglial QUIN in brain regions known to be responsive to infusion of NMDA antagonists such as ketamine. Further work in this area could lead to a greater understanding of the pathophysiology of depressive disorders and pave the way for novel NMDA receptor therapies or immune-modulating strategies.

  18. Effect of quinolinic acid-induced lesions of the nucleus accumbens core on performance on a progressive ratio schedule of reinforcement: implications for inter-temporal choice. (United States)

    Bezzina, G; Body, S; Cheung, T H C; Hampson, C L; Deakin, J F W; Anderson, I M; Szabadi, E; Bradshaw, C M


    The nucleus accumbens core (AcbC) is believed to contribute to the control of operant behaviour by reinforcers. Recent evidence suggests that it is not crucial for determining the incentive value of immediately available reinforcers, but is important for maintaining the values of delayed reinforcers. This study aims to examine the effect of AcbC lesions on performance on a progressive-ratio schedule using a quantitative model that dissociates effects of interventions on motor and motivational processes (Killeen 1994 Mathematical principles of reinforcement. Behav Brain Sci 17:105-172). Rats with bilateral quinolinic acid-induced lesions of the AcbC (n = 15) or sham lesions (n = 14) were trained to lever-press for food-pellet reinforcers under a progressive-ratio schedule. In Phase 1 (90 sessions) the reinforcer was one pellet; in Phase 2 (30 sessions), it was two pellets; in Phase 3, (30 sessions) it was one pellet. The performance of both groups conformed to the model of progressive-ratio performance (group mean data: r2 > 0.92). The motor parameter, delta, was significantly higher in the AcbC-lesioned than the sham-lesioned group, reflecting lower overall response rates in the lesioned group. The motivational parameter, a, was sensitive to changes in reinforcer size, but did not differ significantly between the two groups. The AcbC-lesioned group showed longer post-reinforcement pauses and lower running response rates than the sham-lesioned group. The results suggest that destruction of the AcbC impairs response capacity but does not alter the efficacy of food reinforcers. The results are consistent with recent findings that AcbC lesions do not alter sensitivity to reinforcer size in inter-temporal choice schedules.

  19. L-theanine prevent quinolinic acid induced motor deficit and striatal neurotoxicity: Reduction in oxido-nitrosative stress and restoration of striatal neurotransmitters level. (United States)

    Jamwal, Sumit; Singh, Shamsher; Gill, Jaskamal Singh; Kumar, Puneet


    L-theanine has been documented to possess anti-oxidant, anti-inflammatory and neuroprotective potential in various animal models of neurological disorders. The present study was anticipated to investigate the effect of L-theanine against quinolinic acid induced motor deficits, oxido-nitrosative stress, neuro-inflammation and neurotransmitters alteration in rats. Rats were stereotaxically injected QA (200nmol/2µl saline; intrastriatal); bilaterally on 0 day and L-theanine (25 & 50mg/kg; p.o.) was administered for 21 days starting from day 1 of QA injection. Either, L-NAME (10mg/kg; i.p.), a nitric oxide synthase inhibitor and L-arginine (50mg/kg; i.p.), a nitric oxide synthase precursor were administered with L-theanine in respective groups. Behavioral observations were evaluated on weekly basis using rota-rod, grip strength, narrow beam walking and open field test. QA treatment induces significant alteration in body weight, motor coordination, oxidative defense, pro-inflammatory cytokines and striatal neurotransmitters level. L-theanine treatment alone, at both the tested doses, significantly attenuated QA induced alterations. In addition, treatment of L-theanine with L-NAME significantly enhances the protective effect of L-theanine whereas treatment of L-theanine with L-arginine significantly ameliorated the protective effect of L-theanine. The protective effect of L-theanine is attributed to its anti-oxidant, anti-inflammatory and modulatory effect on nitric oxide pathway and neurotransmitters level in striatum. This suggests use of L-theanine in the clinical settings of HD. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Synthesis of 2-azetidinones substituted quinoline derivative

    Directory of Open Access Journals (Sweden)

    Mashelkar Uday C.


    Full Text Available Acetanilide is converted into 2-chloro-3-formyl quinoline by reacting with DMF-POCl3 at 80-90ºC and then condensed with aromatic primary amines to give Schiff bases (3a-3c. These Schiff bases are then reacted with acid chlorides in the presence of base in toluene to give 1, 3, 4-substituted 2-azetidinones.

  1. Direct One-Pot Synthesis of Primary 4-Amino-2,3-diaryl-quinolines via Suzuki-Miyaura Cross-Coupling of 2-Aryl-4-azido-3-iodoquinolines with Arylboronic Acids

    Directory of Open Access Journals (Sweden)

    Mamasegare Mabel Mphahlele


    Full Text Available Palladium-catalyzed Suzuki-Miyaura cross-coupling of 2-aryl-4-azido-3-iodo-quinolines with arylboronic acids afforded the corresponding primary 4-amino-2,3-diarylquinolines in a single-pot operation along with symmetrical biaryls and traces of the 2,3-diaryl-4-azidoquinolines. A plausible mechanism, which implicates palladium hydride species in the reduction of the incipient 2,3-diaryl-4-azidoquinolines to afford the 4-amino-2,3-diarylquinolines is proposed.

  2. Cathepsin L plays a role in quinolinic acid-induced NF-Κb activation and excitotoxicity in rat striatal neurons.

    Directory of Open Access Journals (Sweden)

    Yan-Ru Wang

    Full Text Available The present study seeks to investigate the role of cathepsin L in glutamate receptor-induced transcription factor nuclear factor-kappa B (NF-κB activation and excitotoxicity in rats striatal neurons. Stereotaxic administration of the N-methyl-d-aspartate (NMDA receptor agonist Quinolinic acid (QA into the unilateral striatum was used to produce the in vivo excitotoxic model. Co-administration of QA and the cathepsin L inhibitor Z-FF-FMK or 1-Naphthalenesulfonyl-IW-CHO (NaphthaCHO was used to assess the contribution of cathepsin L to QA-induced striatal neuron death. Western blot analysis and cathepsin L activity assay were used to assess the changes in the levels of cathepsin L after QA treatment. Western blot analysis was used to assess the changes in the protein levels of inhibitor of NF-κB alpha isoform (IκB-α and phospho-IκB alpha (p-IκBα after QA treatment. Immunohistochemical analysis was used to detect the effects of Z-FF-FMK or NaphthaCHO on QA-induced NF-κB. Western blot analysis was used to detect the effects of Z-FF-FMK or NaphthaCHO on QA-induced IκB-α phosphorylation and degradation, changes in the levels of IKKα, p-IKKα, TP53, caspase-3, beclin1, p62, and LC3II/LC3I. The results show that QA-induced loss of striatal neurons were strongly inhibited by Z-FF-FMK or NaphthaCHO. QA-induced degradation of IκB-α, NF-κB nuclear translocation, up-regulation of NF-κB responsive gene TP53, and activation of caspase-3 was strongly inhibited by Z-FF-FMK or NaphthaCHO. QA-induced increases in beclin 1, LC3II/LC3I, and down-regulation of p62 were reduced by Z-FF-FMK or NaphthaCHO. These results suggest that cathepsin L is involved in glutamate receptor-induced NF-κB activation. Cathepsin L inhibitors have neuroprotective effects by inhibiting glutamate receptor-induced IκB-α degradation and NF-κB activation.

  3. Hydrodenitrogenation of quinoline and acridine

    Energy Technology Data Exchange (ETDEWEB)

    Reiff, Jr., E. K.


    The hydrodenitrogenation of quinoline and of acridine was studied in a batch autoclave reactor between 342 and 353/sup 0/C and between 500 and 2000 psig. The several commercial hydrotreating catalysts examined decreased in activity in the following order for quinoline hydrodenitrogenation: Ni--Mo/Al/sub 2/O/sub 3/, Ni--W/Al/sub 2/O/sub 3/, Ni--W/SiO/sub 2/--Al/sub 2/O/sub 3/, and Co--Mo/Al/sub 2/O/sub 3/. The total nitrogen removal rate for quinoline was slightly greater than that for acridine and both followed pseudo first-order kinetics over a conversion range of 0 to 50%. Hydrogenation and cracking steps were both kinetically limiting. Nitrogen-containing reaction products for quinoline hydrodenitrogenation were 1,2,3,4-tetrahydroquinoline, 5,6,7,8-tetrahydroquinoline, decahydroquinoline and o-propylaniline. At 342/sup 0/C and 500 psig quinoline and 1,2,3,4-tetrahydroquinoline were in thermodynamic equilibrium, and the disappearance of the lumped group of quinoline plus 1,2,3,4-tetrahydroquinoline followed pseudo first-order kinetics. Sixteen nitrogen-containing reaction products were found for acridine hydrodenitrogenation, including 1,2,3,4-tetrahydroacridine, 1,2,3,4,9,10,13,14-octahydroacridine, sym-octahydroacridine, perhydroacridine, and o-(methylenecyclohexane)aniline. The hydrogenolysis step for both quinoline and acridine appears to be through hydrogenated forms of these compounds. This is supported by bond strength arguments.

  4. Quinoline biodegradation by filamentous fungus Cunninghamella elegans and adaptive modifications of the fungal membrane composition. (United States)

    Felczak, Aleksandra; Bernat, Przemysław; Różalska, Sylwia; Lisowska, Katarzyna


    Quinoline, which belongs to N-heterocyclic compounds, occurs naturally in the environment and is used in numerous industrial processes. The structures of various chemicals, such as dyes and medicines, are based on this compound. Due to that fact, quinoline and its derivatives are widely distributed in environment and can exert toxic effects on organisms from different trophic levels. The ability of the filamentous fungus Cunninghamella elegans IM 1785/21Gp to degrade quinoline and modulate the membrane composition in response to the pollutant was studied. C. elegans IM 1785/21Gp removes quinoline with high efficiency and transforms the pollutant into two novel hydroxylated derivatives, 2-hydroxyquinoline and 3-hydroxyquinoline. Moreover, due to the disruption in the membrane stability by quinoline, C. elegans IM 1785/21Gp modulates the fatty acid composition and phospholipid profile.

  5. A quinoline based pH sensitive ratiometric fluorescent sensor ...

    Indian Academy of Sciences (India)

    A new quinoline based hydrazone was synthesized via a condensation reaction and characterized by NMR, mass and single crystal X-ray diffraction studies. It was investigated for suitability as a reversible ratiometric fluorescent pH sensor in acidic pH region. The sensor exhibits intramolecular charge transfer (ICT) type ...

  6. PEG1000-Based Dicationic Acidic Ionic Liquid Catalyzed One-Pot Synthesis of 4-Aryl-3-Methyl-1-Phenyl-1H-Benzo[h]pyrazolo [3,4-b]quinoline-5,10-Diones via Multicomponent Reactions

    Directory of Open Access Journals (Sweden)

    Yi-Ming Ren


    Full Text Available A novel and green approach for efficient and rapid synthesis of 4-aryl-3-methyl-1-phenyl-1H-benzo[h]pyrazolo[3,4-b]quinoline-5,10-diones has been accomplished by the one-pot condensation reaction of aromatic aldehydes, 3-methyl-1-phenyl-1H-pyrazol-5-amine and 2-hydroxynaphthalene-1,4-dione using PEG1000-based dicationic acidic ionic liquid (PEG1000-DAIL as a catalyst was reported. Recycling studies have shown that the PEG1000-DAIL can be readily recovered and reused several times without significant loss of activity. The key advantages are the short reaction time, high yields, simple workup, and recovered catalyst.

  7. Multicomponent Dipolar Cycloaddition Strategy: Combinatorial Synthesis of Novel Spiro-Tethered Pyrazolo[3,4-b]quinoline Hybrid Heterocycles. (United States)

    Sumesh, Remani Vasudevan; Muthu, Muthumani; Almansour, Abdulrahman I; Suresh Kumar, Raju; Arumugam, Natarajan; Athimoolam, S; Jeya Yasmi Prabha, E Arockia; Kumar, Raju Ranjith


    The stereoselective syntheses of a library of novel spiro-tethered pyrazolo[3,4-b]quinoline-pyrrolidine/pyrrolothiazole/indolizine-oxindole/acenaphthene hybrid heterocycles have been achieved through the 1,3-dipolar cycloaddition of azomethine ylides generated in situ from α-amino acids and 1,2-diketones to dipolarophiles derived from pyrazolo[3,4-b]quinoline derivatives.

  8. Quinoline antimalarials: mechanisms of action and resistance. (United States)

    Foley, M; Tilley, L


    The quinoline-containing antimalarial drugs, chloroquine, quinine and mefloquine, are a vital part of our chemotherapeutic armoury against malaria. These drugs are thought to act by interfering with the digestion of haemoglobin in the blood stages of the malaria life cycle. Chloroquine is a dibasic drug which diffuses down the pH gradient to accumulate about a 1000-fold in the acidic vacuole of the parasite. The high intravacuolar concentration of chloroquine is proposed to inhibit the polymerisation of haem. As a result, the haem which is released during haemoglobin breakdown builds up to poisonous levels, thereby killing the parasite with its own toxic waste. The more lipophilic quinolinemethanol drugs, mefloquine and quinine, are not concentrated so extensively in the food vacuole and probably have alternative sites of action. The technique of photoaffinity labelling has been used to identify a series of proteins which interact specifically with mefloquine. These studies have led us to speculate that the quinolinemethanols bind to high density lipoproteins in the serum and are delivered to the erythrocytes where they interact with an erythrocyte membrane protein, known as stomatin, and are then transferred to the intracellular parasite via a pathway used for the uptake of exogenous phospholipid. The final target(s) of quinine and mefloquine action are not yet fully characterised, but may include parasite proteins with apparent molecular weights of 22 kDa and 36 kDa. As resistance to the quinoline antimalarials rises inexorably, there is an urgent need to understand the molecular basis for decreased drug sensitivity. A parasite-encoded homologue of P-glycoprotein has been implicated in the development of drug resistance, possibly by controlling the level of accumulation of the quinoline-containing drugs. As our molecular understanding of these processes increases, it should be possible to design novel antimalarial strategies which circumvent the problem of drug

  9. Electrochemical oxidation of quinoline aqueous solution on β-PbO2 anode and the evolution of phytotoxicity on duckweed. (United States)

    Ma, Xiangjuan; Bian, Lixia; Ding, Jingfeng; Wu, Yaping; Xia, Huilong; Li, Jionghui


    Electrochemical oxidation of quinoline on a β-PbO2 electrode modified with fluoride resin and the comprehensive toxicity of intermediates formed during oxidation on duckweed were investigated in detail. The results showed that quinoline was initially hydroxylated at the C-2 and C-8 positions by hydroxyl radicals (·OH) electro-generated on a β-PbO2 anode, yielding 2(1H)-quinolinone and 8-hydroxyquinoline, then undergoing ring cleavage to form pyridine, nicotinic acid, pyridine-2-carboxaldehyde and acetophenone, which were ultimately converted to biodegradable organic acids. NO3- was the final form of quinoline-N. The growth of duckweed exposed to the oxidized quinoline solution was gradually inhibited with the decrease in pH and the formation of intermediates. However, the growth inhibition of duckweed could be eliminated beyond 120 min of oxidation, indicating the comprehensive toxicity of the quinoline solution reduced when the amount of quinoline removed was above 80%. Additionally, the adjustment of the pH to 7.5 and the addition of nutrients to the treated quinoline solution before culturing duckweed could obviously alleviate the inhibition on duckweed. Thus, partial electrochemical degradation of quinoline offers a cost-effective and clean alternative for pretreatment of wastewater containing nitrogen-heterocyclic compounds before biological treatment. The duckweed test presents a simple method for assessing the comprehensive toxicity of intermediates.

  10. Cytochrome P450 oxidation of the thiophene-containing anticancer drug 3-[(quinolin-4-ylmethyl)-amino]-thiophene-2-carboxylic acid (4-trifluoromethoxy-phenyl)-amide to an electrophilic intermediate. (United States)

    Medower, Christine; Wen, Lian; Johnson, William W


    Compounds that are enzymatically transformed to reactive intermediates are common in nature. Some drugs and many phytochemicals that contain a thiophene ring are oxidized by cytochrome P450 to biological reactive intermediates (BRI) that can covalently bind to thiol nucleophiles. The investigational anticancer agent 3-[(quinolin-4-ylmethyl)-amino]-thiophene-2-carboxylic acid (4-trifluoromethoxy-phenyl)-amide (OSI-930) contains a thiophene moiety that can be oxidized by P450s to an apparent sulfoxide, which can react via Michael-addition to the 5-position of the thiophene ring, as demonstrated by mass spectral characterization of several thioether conjugates of the presumed thiophene S-oxide. Furthermore, a stable deuterium isotope retention experiment in which solvent deuterium was incorporated into the thiophene verifies the sulfoxide pathway. Various thiol nucleophiles are shown by tandem mass spectra to bind with this BRI, which is activated by P450 3A4 and to a slight degree, P450 2D6. Yet various safe drugs, phytochemicals, and endogenous molecules, all noted for their activation to BRI, are not toxic at a normal dose. Thus, multiple features determine any consequence of a BRI, with these complexities determining why one BRI is benign while another is not. The retention of covalent protein adducts of radio-labeled intermediate rat tissue has a half-life of about 1-1.5 days; hence, modified protein is cleared and replaced relatively quickly.

  11. Influence of pH, buffers and role of quinolinic acid, a novel iron chelating agent, in the determination of hydroxyl radical scavenging activity of plant extracts by Electron Paramagnetic Resonance (EPR). (United States)

    Fadda, Angela; Barberis, Antonio; Sanna, Daniele


    The Fenton reaction is used to produce hydroxyl radicals for the evaluation of the antioxidant activity of plant extracts. In this paper the parameters affecting the production of hydroxyl radicals and their spin trapping with DMPO were studied. The use of quinolinic acid (Quin) as an Fe(II) ligand was proposed for antioxidant activity determination of Green tea, orange juice and asparagus extracts. Quin, buffers and pH affect the DMPO-OH signal intensity of the EPR spectra. Quin/Fe(II) and low pH enhance the OH generation. Phosphate and Tris-HCl buffers decrease the signal intensity measured in Fe(II)-sulfate and Fe(II)-Quin systems. The extracts were analyzed with Fenton systems containing Fe(II)-sulfate and Fe(II)-Quin with and without buffer. The highest activity was shown with Fe(II)-Quin without buffer, this system being less influenced by pH and chelating agents present in the extracts. This paper will help researchers to better design spin trapping experiments for food matrices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Crystal Structures of the Iron–Sulfur Cluster-Dependent Quinolinate Synthase in Complex with Dihydroxyacetone Phosphate, Iminoaspartate Analogues, and Quinolinate

    Energy Technology Data Exchange (ETDEWEB)

    Fenwick, Michael K. [Cornell Univ., Ithaca, NY (United States); Ealick, Steven E. [Cornell Univ., Ithaca, NY (United States)


    The quinolinate synthase of prokaryotes and photosynthetic eukaryotes, NadA, contains a [4Fe-4S] cluster with unknown function. We report crystal structures of Pyrococcus horikoshii NadA in complex with dihydroxyacetone phosphate (DHAP), iminoaspartate analogues, and quinolinate. DHAP adopts a nearly planar conformation and chelates the [4Fe-4S] cluster via its keto and hydroxyl groups. The active site architecture suggests that the cluster acts as a Lewis acid in enediolate formation, like zinc in class II aldolases. The DHAP and putative iminoaspartate structures suggest a model for a condensed intermediate. The ensemble of structures suggests a two-state system, which may be exploited in early steps.

  13. Electrochemical mineralization pathway of quinoline by boron-doped diamond anodes. (United States)

    Wang, Chunrong; Ma, Keke; Wu, Tingting; Ye, Min; Tan, Peng; Yan, Kecheng


    Boron-doped diamond anodes were selected for quinoline mineralization, and the resulting intermediates, phenylpropyl aldehyde, phenylpropionic acid, and nonanal were identified and followed during quinoline oxidation by gas chromatography-mass spectrometry and high-performance liquid chromatography. The evolutions of formic acid, acetic acid, oxalic acid, NO2(-), NO3(-), and NH4(+) were quantified. A new reaction pathway for quinoline mineralization by boron-doped diamond anodes has been proposed, where the pyridine ring in quinoline is cleaved by a hydroxyl radical giving phenylpropyl aldehyde and NH4(+). Phenylpropyl aldehyde is quickly oxidized into phenylpropionic acid, and the benzene ring is cleaved giving nonanal. This is further oxidized to formic acid, acetic acid, and oxalic acid. Finally, these organic intermediates are mineralized to CO2 and H2O. NH4(+) is also oxidized to NO2(-) and on to NO3(-). The results will help to gain basic reference for clearing intermediates and their toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Degradation of quinoline by wet oxidation - kinetic aspects and reaction mechanisms

    DEFF Research Database (Denmark)

    Thomsen, A.B.


    The high temperature, high pressure wet oxidation reaction of quinoline has been studied as a function of initial concentration, pH and temperature. At neutral to acidic pH, it is effective in the oxidation of quinoline at 240 degrees C and above, whereas under alkaline conditions the reaction...... was used as a method for verifying and quantifying the reaction products. Fifteen reaction products were identified and quantitatively determined. accounting for 70% of the carbon present after treatment, Nicotinic acid was a main product, accounting for up to 35% of the parent substance, The formation...

  15. Difluoro[2-(quinolin-2-ylphenolato]borane

    Directory of Open Access Journals (Sweden)

    Xi Yang


    Full Text Available The title compound, C15H10BF2NO, was synthesized by the reaction of 2-(quinolin-2-ylphenol and boron trifluoride etherate. The quinoline ring system and the benzene ring are twisted, making a dihedral angle of 8.3 (2°. In the crystal, π–π interactions between the aromatic rings [centroid–centroid distance = 3.638 (9 Å] link the molecules into chains propagating in [100].

  16. Moderately delayed post-insult treatment with normobaric hyperoxia reduces excitotoxin-induced neuronal degeneration but increases ischemia-induced brain damage

    Directory of Open Access Journals (Sweden)

    Haelewyn Benoit


    Full Text Available Abstract Background The use and benefits of normobaric oxygen (NBO in patients suffering acute ischemic stroke is still controversial. Results Here we show for the first time to the best of our knowledge that NBO reduces both NMDA-induced calcium influxes in vitro and NMDA-induced neuronal degeneration in vivo, but increases oxygen and glucose deprivation-induced cell injury in vitro and ischemia-induced brain damage produced by middle cerebral artery occlusion in vivo. Conclusions Taken together, these results indicate that NBO reduces excitotoxin-induced calcium influx and subsequent neuronal degeneration but favors ischemia-induced brain damage and neuronal death. These findings highlight the complexity of the mechanisms involved by the use of NBO in patients suffering acute ischemic stroke.

  17. One-pot tandem 1,4-1,2-addition of phosphites to quinolines. (United States)

    De Blieck, Ann; Masschelein, Kurt G R; Dhaene, Fréderic; Rozycka-Sokolowska, Ewa; Marciniak, Bernard; Drabowicz, Jozef; Stevens, Christian V


    Trialkyl and silylated dialkyl phosphites were evaluated as phosphorus nucleophiles for the addition to quinolines in a strong acidic medium allowing consecutive 1,4- and 1,2-addition breaking up the aromatic stabilisation, thereby leading to 2,4-diphosphono-1,2,3,4-tetrahydroquinolines in one single reaction step in moderate to good yields (2-84%).

  18. 3-Hydroxykynurenine potentiates quinolinate but not NMDA toxicity in the rat striatum. (United States)

    Guidetti, P; Schwarcz, R


    L-3-Hydroxykynurenine (L-3-HK) and quinolinate (QUIN) are two metabolites of the kynurenine pathway, the major route of tryptophan degradation in mammals. L-3-HK is a known generator of highly reactive free radicals, whereas QUIN is an endogenous excitotoxin acting specifically at N-methyl-D-aspartate (NMDA) receptors. This study was designed to examine possible synergistic interactions between L-3-HK and QUIN in the rat brain in vivo. Intrastriatal coinjection of 5 nmol L-3-HK and 15 nmol QUIN, i.e. doses which caused no or minimal neurodegeneration on their own, resulted in substantial neuronal loss, determined both behaviourally (apomorphine-induced rotations) and histologically (quantitative assessment of lesion size). The excitotoxic nature of the lesion was verified by tyrosine hydroxylase immunohistochemistry, showing the survival of dopaminergic striatal afferents. There was also a relative sparing of large striatal neurons, and neurodegeneration was prevented both by NMDA receptor blockade (using CGP 40116) and free radical scavenging [using N-tert-butyl-alpha-(2-sulphophenyl)-nitrone, S-PBN]. The pro-excitotoxic features of L-3-HK were especially pronounced at low QUIN doses and were not observed when QUIN was substituted by NMDA. Notably, the effect of L-3-HK was not due to its intracerebral conversion to QUIN and was duplicated by equimolar D,L-3-HK. These data indicate that an elevation of L-3-HK levels constitutes a significant hazard in situations of excitotoxic injury. Pharmacological interventions aimed at decreasing L-3-HK formation may therefore be particularly useful for the treatment of neurological diseases which are associated with an abnormally enhanced flux through the kynurenine pathway.

  19. Type 1 cannabinoid receptor mapping with [{sup 18}F]MK-9470 PET in the rat brain after quinolinic acid lesion: a comparison to dopamine receptors and glucose metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Casteels, Cindy [KU Leuven and University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); KU Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); University Hospital Gasthuisberg, Division of Nuclear Medicine, Leuven (Belgium); Martinez, Emili; Camon, Lluisa; Vera, Nuria de; Planas, Anna M. [IDIBAPS, Institute for Biomedical Research (IIBB-CSIC), Barcelona (Spain); Bormans, Guy [KU Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium); KU Leuven, Laboratory for Radiopharmacy, Leuven (Belgium); Baekelandt, Veerle [KU Leuven, Laboratory for Neurobiology and Gene Therapy, Leuven (Belgium); Laere, Koen van [KU Leuven and University Hospital Leuven, Division of Nuclear Medicine, Leuven (Belgium); KU Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven (Belgium)


    Several lines of evidence imply early alterations in metabolic, dopaminergic and endocannabinoid neurotransmission in Huntington's disease (HD). Using [{sup 18}F]MK-9470 and small animal PET, we investigated cerebral changes in type 1 cannabinoid (CB{sub 1}) receptor binding in the quinolinic acid (QA) rat model of HD in relation to glucose metabolism, dopamine D{sub 2} receptor availability and amphetamine-induced turning behaviour. Twenty-one Wistar rats (11 QA and 10 shams) were investigated. Small animal PET acquisitions were conducted on a Focus 220 with approximately 18 MBq of [{sup 18}F]MK-9470, [{sup 18}F]FDG and [{sup 11}C]raclopride. Relative glucose metabolism and parametric CB{sub 1} receptor and D{sub 2} binding images were anatomically standardized to Paxinos space and analysed voxel-wise using Statistical Parametric Mapping (SPM2). In the QA model, [{sup 18}F]MK-9470 uptake, glucose metabolism and D{sub 2} receptor binding were reduced in the ipsilateral caudate-putamen by 7, 35 and 77%, respectively (all p < 2.10{sup -5}), while an increase for these markers was observed on the contralateral side (>5%, all p < 7.10{sup -4}). [{sup 18}F]MK-9470 binding was also increased in the cerebellum (p = 2.10{sup -5}), where it was inversely correlated to the number of ipsiversive turnings (p = 7.10{sup -6}), suggesting that CB{sub 1} receptor upregulation in the cerebellum is related to a better functional outcome. Additionally, glucose metabolism was relatively increased in the contralateral hippocampus, thalamus and sensorimotor cortex (p = 1.10{sup -6}). These data point to in vivo changes in endocannabinoid transmission, specifically for CB{sub 1} receptors in the QA model, with involvement of the caudate-putamen, but also distant regions of the motor circuitry, including the cerebellum. These data also indicate the occurrence of functional plasticity on metabolism, D{sub 2} and CB{sub 1} neurotransmission in the contralateral hemisphere. (orig.)

  20. Dissociative photoionization of quinoline and isoquinoline

    NARCIS (Netherlands)

    Bouwman, J.; Sztáray, B.; Oomens, J.; Hemberger, P.; Bodi, A.


    Two nitrogen-containing polycyclic aromatic hydrocarbon isomers of C9H7N composition, quinoline, and isoquinoline have been studied by imaging photoelectron photoion coincidence spectroscopy at the VUV beamline of the Swiss Light Source. High resolution threshold photoelectron spectra have been

  1. 4-Chlorobenzoic acid–quinoline (1/1

    Directory of Open Access Journals (Sweden)

    Kazuma Gotoh


    Full Text Available In the title compound, C7H5ClO2·C9H7N, the 4-chlorobenzoic acid molecule is almost planar, with a dihedral angle of 2.9 (14° between the carboxy group and the benzene ring. In the crystal, the two components are connected by an O—H...N hydrogen bond. In the hydrogen-bonded unit, the dihedral angle between the quinoline ring system and the benzene ring of the benzoic acid is 44.75 (4°. The two components are further linked by intermolecular C—H...O hydrogen bonds, forming a layer parallel to the ab plane.

  2. Rh(I)-Catalyzed Direct Arylation of Pyridines and Quinolines

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Ashley; Lewis, Jared; Bergman, Robert; Ellman, Jonathan


    additive proved even more effective, with the yield of 1a improving to 61% (entry 2). Further enhancement in yield was not observed upon the inclusion of other additives such as MgO (entry 3), various organic bases (entries 4, 5), or a protic acid source (entry 6). Absolute concentration proved very important, with the best results being obtained at relatively high concentrations of the aryl bromide (compare entries 7 and 8). A marginal improvement was observed upon running the reaction with 6 equivalents of 2-methyl pyridine (entry 9). The reaction temperature could also be increased to 175 or 190 C while maintaining reaction yield, to enable the reaction time to be reduced to 24 h (entries 10 and 11). In summary, we have developed a Rh(I)-catalyzed strategy for the direct arylation of pyridines and quinolines. The heterocycle is used without the need for prefunctionalization, and all reaction components are inexpensive and readily available. The strategy represents an expeditious route to an important class of bis(hetero)aryls and should be of broad utility.

  3. Transformation of indole and quinoline by Desulfobacterium indolicum (DSM 3383)

    DEFF Research Database (Denmark)

    Licht, D.; Johansen, S.S.; Arvin, E.


    kinetics. The kinetic parameters for indole were an apparent maximum specific transformation rate (V-Amax) of 263 mu mol mg total protein(-1) day(-1) and an apparent half-saturation constant (K-Am) of 139 mu M. The V-Amax for quinoline was 170 mu mol mg total protein(-1) day(-1) and K-Am was 92 mu M....... Oxindole inhibited indole hydroxylation whereas 2-hydroxyquinoline stimulated quinoline hydroxylation. An adaptation period of approximately 20 days was required before transformation of 2-hydroxyquinoline in cultures previously grown on quinoline. Indole and quinoline were hydroxylated with a lag phase...

  4. Quinolines derivatives as novel sunscreening agents. (United States)

    Polonini, Hudson C; Dias, Rafael M P; Souza, Isabela O; Gonçalves, Karla Mara; Gomes, Tiago B B; Raposo, Nádia R B; da Silva, Adilson David


    Currently, the research and development of sunscreens play an important role on the synthesis of actives that are stable in various kinds of formulations-in addition to their efficiency and broad spectrum of protection against ultraviolet radiation. Our objective here was to synthesize new sunscreening chemical agents using quinoline as a base molecule. Twelve quinoline derivatives were synthesized, four of them novel molecules, and their photoprotective activity was determined in vitro using diffuse transmittance spectrophotometry. We determined their SPF, UVAPF, UVA/UVB ratio, critical wavelength and Boots Star Rating. The quinolines derivatives presented a varied profile of photoprotection, their SPF ranging from 2 to 11 and their UVAPF from 2 to 7. In terms of the critical wavelength, all molecules were considered of broad-spectrum by different classifications. Regarding the Boots Star Rating, one compound received no rating, seven of them received a three stars rating, three received a four stars rating and three were given a five stars rating. The molecules showed in the present work have a wide range of possibilities for creating new sunscreen products, once they have good SPF or UVAPF for single molecules, and they also possess other different qualities that can act synergistically. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Synthesis of some quinoline-pyrazoline-based naphthalenyl ...

    African Journals Online (AJOL)

    Purpose: To prepare and evaluate some quinoline-pyrazoline-based naphthalenyl thiazole derivatives as antimicrobial agents. Methods: Some quinoline-pyrazoline-based naphthalenyl thiazoles (5a-5e and 6a-6e) were prepared by reacting 5-(2-chloroquinolin-3-yl)-3-substitutedphenyl-4 ...

  6. An efficient access to the synthesis of novel 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H-one derivatives

    Directory of Open Access Journals (Sweden)

    Wentao Gao


    Full Text Available An efficient access to the tetracyclic-fused quinoline systems, 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H-one derivatives 4a–l, is described, involving the intramolecular Friedel–Crafts acylation reaction of 2-(phenoxymethyl-4-phenylquinoline-3-carboxylic acid derivatives 3a–l aided by the treatment with PPA (polyphosphoric acid or Eaton’s reagent. The required starting compound (2 was obtained by Friedländer reaction of 2-aminobenzophenone (1 with 4-chloroethylacetoacetate by using CAN (cerium ammonium nitrate, 10 mol % as catalyst at room temperature. The substrates 3a–l were prepared through one-pot reaction of ethyl 2-(chloromethyl-4-phenylquinoline-3-carboxylate (2 and substituted phenols. Our developed strategy, involving a three-step route, offers easy access to tetracyclic-fused quinoline systems in short reaction times, and the products are obtained in moderate to good yields.

  7. Thermodynamics of organic mixtures containing amines. VIII. Systems with quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F., Grupo Especializado en Termodinamica de Equilibrio entre Fases, Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, E-47071 Valladolid (Spain)], E-mail:; Domanska, Urszula; Zawadzki, Maciej [Physical Chemistry Division, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw (Poland)


    (Solid + liquid) equilibrium temperatures for mixtures containing quinoline and 1-dodecanol, 1-hexadecanol, or 1-octadecanol have been measured using a dynamic method. (Quinoline + benzene, +alkane, or +1-alkanol) systems were investigated using DISQUAC. The corresponding interaction parameters are reported. The model yields a good representation of molar excess Gibbs free energies, G{sup E}, molar excess enthalpies, H{sup E}, and of the (solid + liquid) equilibria, SLE. Interactional and structural effects were analysed comparing H{sup E} and the molar excess internal energy at constant volume, U{sub V}{sup E}. It was encountered that structural effects are very important in systems involving alkanes or 1-alkanols. Interactions between amine molecules are stronger in mixtures with quinoline than in those containing pyridine, which was ascribed to the higher polarizability of quinoline.

  8. Carbon and hydrogen isotope fractionation during anaerobic quinoline degradation. (United States)

    Fischer, Anko; Weber, Stefanie; Reineke, Anne-Kirsten; Hollender, Juliane; Richnow, Hans-H


    Quinoline is a N-heterocyclic compound often found at tar oil contaminated field sites. To provide information whether stable isotope analysis can help to characterize the fate of quinoline within contaminated aquifers, carbon and hydrogen isotope fractionation of quinoline were investigated during biodegradation under sulfate-reducing conditions. No significant carbon isotope effect was observed, however, substantial hydrogen isotope fractionation was detected. Thus, hydrogen isotope fractionation may be used as an indicator for in situ biodegradation of quinoline. The bulk hydrogen isotope enrichment factor was εH(bulk)=-33±12‰. During the biodegradation of quinoline the primary intermediate 2-hydroxyquinoline was detected indicating hydroxylation at the C2-position. According to this reaction mechanism, the reactive position specific hydrogen enrichment factor (εH(reactive position)) and apparent kinetic hydrogen isotope effect (AKIE(H)) were calculated and gave values of εH(reactive position)=-205±75‰ and AKIE(H)=1.26±0.12, respectively. The missing carbon isotope effect may be explained by strong masking or an enzymatic direct side-on insertion of oxygen from the MoOH(H) group of the molybdenum center across the CH bond at the C2-position of quinoline with concomitant hydride transfer. The later assumption is supported by recent studies showing that initial step of hydroxylation of N-heteroaromatic compounds proceeds via a similar reaction mechanism. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Rhodium-catalyzed ortho C-H bond activation of arylamines for the synthesis of quinoline carboxylates. (United States)

    Gadakh, Sunita K; Dey, Soumen; Sudalai, A


    The rhodium catalyzed annulation of anilines with alkynic esters allowing for the high-yield synthesis of quinoline carboxylates with excellent regioselectivity is described. This unprecedented reaction employs either formic acid as the C1 source and reductant or copper(ii) as the oxidant and is proposed to proceed via rhodacycle of in situ generated amide and enamine ester followed by ortho C-H activation of arylamines with rhodium as the catalyst.

  10. Essential role of Bordetella NadC in a quinolinate salvage pathway for NAD biosynthesis. (United States)

    Brickman, Timothy J; Suhadolc, Ryan J; McKelvey, Pamela J; Armstrong, Sandra K


    Nicotinamide adenine dinucleotide (NAD) is produced via de novo biosynthesis pathways and by salvage or recycling routes. The classical Bordetella bacterial species are known to be auxotrophic for nicotinamide or nicotinic acid. This study confirmed that Bordetella bronchiseptica, Bordetella pertussis and Bordetella parapertussis have the recycling/salvage pathway genes pncA and pncB, for use of nicotinamide or nicotinic acid, respectively, for NAD synthesis. Although these Bordetellae lack the nadA and nadB genes needed for de novo NAD biosynthesis, remarkably, they have one de novo pathway gene, nadC, encoding quinolinate phosphoribosyltransferase. Genomic analyses of taxonomically related Bordetella and Achromobacter species also indicated the presence of an 'orphan' nadC and the absence of nadA and nadB. When supplied as the sole NAD precursor, quinolinate promoted B. bronchiseptica growth, and the ability to use it required nadC. Co-expression of Bordetella nadC with the nadB and nadA genes of Paraburkholderia phytofirmans allowed B. bronchiseptica to grow in the absence of supplied pyridines, indicative of de novo NAD synthesis and functional confirmation of Bordetella NadC activity. Expression of nadC in B. bronchiseptica was influenced by nicotinic acid and by a NadQ family transcriptional repressor, indicating that these organisms prioritize their use of pyridines for NAD biosynthesis. © 2016 John Wiley & Sons Ltd.

  11. Design, Synthesis and Qualitative Structure Activity Relationship Evaluations of Quinoline-Based Bisarylimidazoles as Antibacterial Motifs. (United States)

    Al-Qawasmeh, Raed A; Huthail, Basil B; Sinnokrot, Mutasem O; Semreen, Mohammad H; Odeh, Raed A; Abu-Zarga, Musa H; Tarazi, Hamadeh; Yousef, Imad A; Al-Tel, Taleb H


    The emergence of drug-resistant bacteria in clinical practice has propelled a concerted effort to find new classes of antibiotics that will circumvent current modes of resistance. We previously described a set of imidazopyridine antibacterial leads that contain a core composed of benzimidazole and a central phthalic acid linker. These compounds showed potent antibacterial properties against a wide range of Gram-positive and Gram-negative bacteria. In this respect, we conducted a systematic exploration of new disubstituted imidazole functionalities on quinoline 4-position as the central linker, to determine the factors that direct the potent antibacterial activity. We found that some of the newly synthesized compounds possessed more potent activity compared to currently available medications. The newly synthesized compounds were screened against several clinical isolates and Staphylococcus aureus, including the methicillinresistant (MRSA) and the methicillin-sensitive (MSAA). The goal of this work is to undertake rigorous testing of new hybrid scaffolds of quinoline flanked by diaryl imidazoles and their structure-activity against a range of bacterial strains. Described herein is the account of the modification of the central linker region, the imidazole functionality, and substituents at the 4-position of the quinoline, and their effect on the antibacterial potency of the resulting derivatives. Our efforts here have been driven by previous reports on the applications of Pfitzinger cyclization protocol. This complexity-generating reaction transforms a relatively simple substrate, into a more complex products with the potential for diversification via functionalization of the resultant acid. We identified compounds that possess potent and broad-spectrum antibacterial activities against clinical isolates and drug resistant strains. Structure-Activity relationships of these compounds were further explored to determine the crucial structural features needed to enhance

  12. cis-Dichloridobis(quinoline-κNplatinum(II nitromethane monosolvate

    Directory of Open Access Journals (Sweden)

    Kwang Ha


    Full Text Available In the title compound, [PtCl2(C9H7N2]·CH3NO2, the PtII cation is four-coordinated in an essentially square-planar environment by two N atoms from two quinoline ligands and two Cl− anions. One of the nearly planar quinoline ligands [maximum deviations = 0.042 (6 and 0.018 (7 Å] is almost perpendicular to the PtCl2N2 unit [maximum deviation = 0.024 (3 Å], making a dihedral angle of 89.6 (1°, whereas the other is slightly inclined to the central plane with a dihedral angle of 74.1 (1°. The dihedral angle between the quinoline ligands is 88.3 (2°. In the crystal, each solvent molecule is linked to the metal complex by weak intermolecular C—H...O hydrogen bonds.

  13. Synthetically simple, click-generated quinoline-based Fe3+ sensors (United States)

    Wang, Zhaoyun; Wang, Hua; Meng, Ting; Hao, Erhong; Jiao, Lijuan


    Simple quinoline-based fluorescent probes for Fe3+ have been efficiently synthesized through ‘click’ reaction. Both probes gave intense fluorescence compared to 8-hydroquinoline in various organic solvents due to the inhibition of the excited state intramolecular photon transfer process, while showing dramatically quenched and red-shifted fluorescence in an aqueous solution, which can be attributed to the hydrogen bond-induced intermolecular excited state proton transfer process. In the presence of Fe3+ or in an acidic condition (pH less than 4.0), both probes showed similar quenching of the emission and over 100 nm red-shifts of their emission maxima. The binding mode between the probes and Fe3+ has been found to be 1:1 based on Job’s plot. A highly sensitive and selective response in their absorption and emission towards Fe3+ over many other metal ions, including Cr3+ and Cu2+, was observed and may be the result of the ground state metal to ligand charge transfer effect from Fe3+ to quinoline ligands.

  14. Grafting polyethylenimine with quinoline derivatives for targeted imaging of intracellular Zn(2+) and logic gate operations. (United States)

    Pan, Yi; Shi, Yupeng; Chen, Junying; Wong, Chap-Mo; Zhang, Heng; Li, Mei-Jin; Li, Cheuk-Wing; Yi, Changqing


    In this study, a highly sensitive and selective fluorescent Zn(2+) probe which exhibited excellent biocompatibility, water solubility, and cell-membrane permeability, was facilely synthesized in a single step by grafting polyethyleneimine (PEI) with quinoline derivatives. The primary amino groups in the branched PEI can increase water solubility and cell permeability of the probe PEIQ, while quinoline derivatives can specifically recognize Zn(2+) and reduce the potential cytotoxicity of PEI. Basing on fluorescence off-on mechanism, PEIQ demonstrated excellent sensing capability towards Zn(2+) in absolute aqueous solution, where a high sensitivity with a detection limit as low as 38.1nM, and a high selectivity over competing metal ions and potential interfering amino acids, were achieved. Inspired by these results, elementary logic operations (YES, NOT and INHIBIT) have been constructed by employing PEIQ as the gate while Zn(2+) and EDTA as chemical inputs. Together with the low cytotoxicity and good cell-permeability, the practical application of PEIQ in living cell imaging was satisfactorily demonstrated, emphasizing its wide application in fundamental biology research. Copyright © 2016. Published by Elsevier B.V.

  15. Synthesis, characterization and emission properties of quinolin-8 ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 116; Issue 5. Synthesis, characterization and emission properties of quinolin-8-olato chelated ruthenium ... Author Affiliations. Bikash Kumar Panda1. Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700 032, India ...

  16. Differential effects of quinoline antimalarials on endocytosis in Plasmodium falciparum. (United States)

    Roberts, Lindi; Egan, Timothy J; Joiner, Keith A; Hoppe, Heinrich C


    The effects of quinoline antimalarials on endocytosis by Plasmodium falciparum was investigated by measuring parasite hemoglobin levels, peroxidase uptake, and transport vesicle content. Mefloquine, quinine, and halofantrine inhibited endocytosis, and chloroquine inhibited vesicle trafficking, while amodiaquine shared both effects. Protease inhibitors moderated hemoglobin perturbations, suggesting a common role for heme binding.

  17. Synthesis, characterization and emission properties of quinolin-8 ...

    Indian Academy of Sciences (India)


    Synthesis, characterization and emission properties of quinolin-8-olato chelated ruthenium organometallics. BIKASH KUMAR PANDA. Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700 032,. India e-mail: MS received 2 June 2004; revised 21 July 2004.

  18. An efficient synthesis of quinolines under solvent-free conditions

    Indian Academy of Sciences (India)


    the development of newer processes for organic trans- formations,7 our attention was drawn to two proto- cols,6b,d in one of which the o-aminobenzaldehyde was generated in situ and reacted immediately with an enolizable ketone to produce a quinoline6b. This reaction was conducted in anhydrous ethanol under.

  19. Synthesis of some quinoline-pyrazoline-based naphthalenyl ...

    African Journals Online (AJOL)

    Original Research Article. Synthesis of some quinoline-pyrazoline-based naphthalenyl thiazole derivatives and their evaluation as potential antimicrobial agents. Mohd Imran1*, Mohammed Afroz Bakht2, Abdul Samad2 and Abida1. 1Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Northern Border University ...

  20. Impact of quinoline on activity and microbial culture of partial nitrification process. (United States)

    Fu, Zhimin; Zhao, Ji


    In this study, the effect of quinoline on nitrification in an activated sludge system was evaluated in batch assays. Quinoline was evaluated to partial nitrification process or to partial nitrification-quinoline degrading process. In partial nitrification assays, 50-150mg/L quinoline presence promoted the ammonium oxidation efficiency (200-100%). Nonetheless, the consumption efficiencies for quinoline were less than 66.6%. On the other hand, in partial nitrification-quinoline degrading process, the promotion effect of quinoline (50-150mg/L) diminished significantly, ammonium oxidation were similarity to the control. However, the consumption efficiencies for quinoline were nearly 100%. DGGE results showed that the bacteria communities varied significantly. Acidovorax sp. JS42 and Acidovorax ebreus TPSY were responsible for ammonium oxidation in partial nitrification process, while Nitrosomonas in partial nitrification-quinoline degrading process. This information might be useful for treating wastewaters of ammonium/quinoline by partial nitrification technology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Sensitive and rapid determination of quinoline yellow in drinks using polyvinylpyrrolidone-modified electrode. (United States)

    Zhang, Shenghui; Shi, Zhen; Wang, Jinshou


    A novel electrochemical sensor using polyvinylpyrrolidone (PVP)-modified carbon paste electrode was developed for the sensitive and rapid determination of quinoline yellow. In 0.1M, pH 6.5 phosphate buffer, an irreversible oxidation wave at 0.97 V was observed for quinoline yellow. PVP exhibited strong accumulation ability to quinoline yellow, and consequently increased the oxidation peak current of quinoline yellow remarkably. The effects of pH value, amount of PVP, accumulation potential and time were studied on the oxidation signals of quinoline yellow. The linear range was from 5×10(-8) to 1×10(-6) M, and the limit of detection was evaluated to be 2.7×10(-8) M. It was used to detect quinoline yellow in different drink samples, and the results consisted with the values that obtained by high-performance liquid chromatography. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. A novel quinoline alkaloid possessing a 7-benzyl group from the centipede, Scolopendra subspinipes. (United States)

    Noda, N; Yashiki, Y; Nakatani, T; Miyahara, K; Du, X M


    The novel quinoline alkaloid scolopendrine was isolated from the centipede, Scolopendra subspinipes mutilans L. Koch. The structure was determined to be 2-hydroxy-7-[(4-hydroxy-3-methoxyphenyl)methyl]-3-methoxy-8-quinolyl sulfate on the basis of high-resolution electron-spray ionization mass spectroscopy and two-dimensional NMR spectral data. Unlike quinoline alkaloids so far reported, scolopendrine is unique in having a 7-benzyl moiety in the quinoline ring.

  3. Quinoline-2-thiol Derivatives as Fluorescent Sensors for Metals, pH and HNO

    Directory of Open Access Journals (Sweden)

    Naphtali A. O’Connor


    Full Text Available A tautomeric equilibrium exists for quinoline-2-thiol and quinoline-2(1H-thione. Quantum mechanical calculations predict the thione is the major tautomer and this is confirmed by the absorption spectra. The utility of quinolone-2-thiol/quinoline-2(1H-thione as a chromophore for developing fluorescent sensors is explored. No fluorescence is observed when excited at absorption maxima, however a fluorescence increase is observed when exposed to HNO, a molecule of import as a cardiovascular therapeutic. Alkylated quinoline-2-thiol derivatives are found to be fluorescent and show a reduction in fluorescence when exposed to metals and changes in pH.

  4. Dimethylurea/citric acid as a highly efficient deep eutectic solvent for ...

    Indian Academy of Sciences (India)

    medium for the efficient synthesis of bis(indolyl)methanes, quinolines and aryl-4, 5-diphenyl-1H-imidazoles. Ease of recovery and reusability of DES with high activity makes this method efficient and eco-friendly. Keywords. Deep eutectic; citric acid; dimethylurea; bis(indolyl)methane; quinoline; aryl-4, 5-diphenyl-1H-.

  5. Relationship between molecular structure and Raman spectra of quinolines (United States)

    Frosch, Torsten; Popp, Jürgen


    DFT calculations were applied to investigate the relationship between the molecular structure and the Raman spectra of quinolines. A variety of different quinolines with increasing complexity was investigated and an aminoquinoline nucleus was found that describes the Raman spectrum of protonated chloroquine. It was discovered that the biological important, rigid C7-chloro group and C4-side chain of chloroquine significantly disturb certain molecular vibrations. The protonation at the N1 position causes dramatic changes of the Raman bands in the wavenumber region between 1500 cm -1 and 1650 cm -1. These bands are putative marker bands of the aminoquinoline drugs for π-π interactions to the hematin targets in malaria infected cells. The calculation of the normal modes and the illustration of the associated atomic displacements are very valuable for a deeper understanding of the associated bands in the Raman spectra.

  6. Experimental and mechanistic analysis of the palladium-catalyzed oxidative C8-selective C-H homocoupling of quinoline N-oxides. (United States)

    Stephens, David E; Lakey-Beitia, Johant; Chavez, Gabriel; Ilie, Carla; Arman, Hadi D; Larionov, Oleg V


    A novel site-selective palladium-catalyzed oxidative C8-H homocoupling reaction of quinoline N-oxides has been developed. The reaction affords substituted 8,8'-biquinolyl N,N'-dioxides that can be readily converted to a variety of functionalized 8,8'-biquinolyls. Mechanistic studies point to the crucial role of the oxidant and a non-innocent behavior of acetic acid as a solvent.

  7. Quinoline Derivatives Are Therapeutic Candidates for Transmissible Spongiform Encephalopathies


    Murakami-Kubo, Ikuko; Doh-ura, Katsumi; Ishikawa, Kensuke; Kawatake, Satoshi; Sasaki, Kensuke; Kira, Jun-ichi; Ohta, Shigeru; Iwaki, Toru


    We previously reported that quinacrine inhibited the formation of an abnormal prion protein (PrPres), a key molecule in the pathogenesis of transmissible spongiform encephalopathy, or prion disease, in scrapie-infected neuroblastoma cells. To elucidate the structural aspects of its inhibiting action, various chemicals with a quinoline ring were screened in the present study. Assays of the scrapie-infected neuroblastoma cells revealed that chemicals with a side chain containing a quinuclidine ...

  8. Quinoline derivatives are therapeutic candidates for transmissible spongiform encephalopathies. (United States)

    Murakami-Kubo, Ikuko; Doh-Ura, Katsumi; Ishikawa, Kensuke; Kawatake, Satoshi; Sasaki, Kensuke; Kira, Jun-Ichi; Ohta, Shigeru; Iwaki, Toru


    We previously reported that quinacrine inhibited the formation of an abnormal prion protein (PrPres), a key molecule in the pathogenesis of transmissible spongiform encephalopathy, or prion disease, in scrapie-infected neuroblastoma cells. To elucidate the structural aspects of its inhibiting action, various chemicals with a quinoline ring were screened in the present study. Assays of the scrapie-infected neuroblastoma cells revealed that chemicals with a side chain containing a quinuclidine ring at the 4 position of a quinoline ring (represented by quinine) inhibited the PrPres formation at a 50% inhibitory dose ranging from 10(-1) to 10(1) micro M. On the other hand, chemicals with a side chain at the 2 position of a quinoline ring (represented by 2,2'-biquinoline) more effectively inhibited the PrPres formation at a 50% inhibitory dose ranging from 10(-3) to 10(-1) micro M. A metabolic labeling study revealed that the action of quinine or biquinoline was not due to any alteration in the biosynthesis or turnover of normal prion protein, whereas surface plasmon resonance analysis showed a strong binding affinity of biquinoline with a recombinant prion protein. In vivo studies revealed that 4-week intraventricular infusion of quinine or biquinoline was effective in prolonging the incubation period in experimental mouse models of intracerebral infection. The findings suggest that quinoline derivatives with a nitrogen-containing side chain have the potential of both inhibiting PrPres formation in vitro and prolonging the incubation period of infected animals. These chemicals are new candidates for therapeutic drugs for use in the treatment of transmissible spongiform encephalopathies.

  9. The Effects of Quinoline and Non-Quinoline Inhibitors on the Kinetics of Lipid-Mediated β-Hematin Crystallization. (United States)

    Fitzroy, Sharné-Maré; Gildenhuys, Johandie; Olivier, Tania; Tshililo, Ndivhuwo Olga; Kuter, David; de Villiers, Katherine Allison


    The throughput of a biomimetic lipid-mediated assay used to investigate the effects of inhibitors on the kinetics of β-hematin formation has been optimized through the use of 24-well microplates. The rate constant for β-hematin formation mediated by monopalmitoyl-rac-glycerol was reduced from 0.17 ± 0.04 min(-1) previously measured in Falcon tubes to 0.019 ± 0.002 min(-1) in the optimized assay. While this necessitated longer incubation times, transferring aliquots from multiple 24-well plates to a single 96-well plate for final absorbance measurements actually improved the overall turnaround time per inhibitor. This assay has been applied to investigate the effects of four clinically relevant antimalarial drugs (chloroquine, amodiaquine, quinidine, and quinine) as well as several short-chain 4-aminoquinoline derivatives and non-quinoline (benzamide) compounds on the kinetics of β-hematin formation. The adsorption strength of these inhibitors to crystalline β-hematin (Kads) was quantified using a theoretical kinetic model that is based on the Avrami equation and the Langmuir isotherm. Statistically significant linear correlations between lipid-mediated β-hematin inhibitory activity and Kads values for quinoline (r(2) = 0.76, P-value = 0.0046) and non-quinoline compounds (r(2) = 0.99, P-stat = 0.0006), as well as between parasite inhibitory activity (D10) and Kads values for quinoline antimalarial drugs and short-chain chloroquine derivatives (r(2) = 0.64, P-value = 0.0098), provide a strong indication that drug action involves adsorption to the surface of β-hematin crystals. Independent support in this regard is provided by experiments that spectrophotometrically monitor the direct adsorption of antimalarial drugs to preformed β-hematin.

  10. A simple and efficient protocol for the synthesis of quinolines catalyzed by chloramine-T

    Directory of Open Access Journals (Sweden)

    P. Leelavathi


    Full Text Available Chloramine-T has been proved as an efficient catalyst for the synthesis of substituted quinolines. In this method, 2-amino aryl ketones were smoothly reacted with ketones to afford the corresponding quinoline derivatives in very good yields. All the reactions were carried out at acetonitrile reflux.

  11. A simple and efficient protocol for the synthesis of quinolines catalyzed by chloramine-T


    P. Leelavathi; Y.Venkateswarlu; S. Ramesh Kumar


    Chloramine-T has been proved as an efficient catalyst for the synthesis of substituted quinolines. In this method, 2-amino aryl ketones were smoothly reacted with ketones to afford the corresponding quinoline derivatives in very good yields. All the reactions were carried out at acetonitrile reflux.

  12. UV action spectroscopy of protonated PAH derivatives. Methyl substituted quinolines

    DEFF Research Database (Denmark)

    Klærke, Benedikte; Holm, Anne; Andersen, Lars Henrik


    Aims. We investigate the production of molecular photofragments upon UV excitation of PAH derivatives, relevant for the interstellar medium. Methods. The action absorption spectra of protonated gas-phase methyl-substituted quinolines (CH3−C9H7NH+) have been recorded in the 215–338 nm spectral range...... the estimated IR relaxation time. Photophysical properties of both nitrogen containing and methyl-substituted PAHs are interesting in an astrophysical context in connection with identifying the aromatic component of the interstellar medium....

  13. Pharmacological effects of a synthetic quinoline, a hybrid of tomoxiprole and naproxen, against acute pain and inflammation in mice: a behavioral and docking study

    Directory of Open Access Journals (Sweden)

    Hossein Hosseinzadeh


    Full Text Available Objective(s: In the present study, we investigated the potential anti-nociceptive activity and acute anti-inflammatory effect of a synthetic quinoline compound (2-(4-Methoxyphenylbenzo[h]quinoline-4-carboxylic acid, QC, possessing structural elements of both naproxen and tomoxiprole drugs. Materials and Methods: The anti-nociceptive activity of QC was evaluated using chemical- and thermal-induced nociception models and its acute anti-inflammatory effect was evaluated by xylene-induced ear edema test in mice. Results: QC displayed a dose dependent effect in both acute anti-nociceptive tests (writhing and hot plate. This compound at dose of 6.562 mg/kg showed a high anti-nociceptive effect near equal to  diclofenac 5 mg/kg. It also showed high anti-inflammatory effects (less than 6.562 mg/kg comparable to those of reference drugs diclofenac (5 mg/kg and celecoxib (100 mg/kg. Docking study showed that this quinoline derivative could inhibit COX-2 enzyme strongly. Conclusion: QC showed high anti-nociceptive and anti-inflammatory effects comparable to reference drugs and can exert its anti-nociceptive and anti-inflammatory activities through COX-2 inhibition.

  14. An atom economical method for the direct synthesis of quinoline derivatives from substituted o-nitrotoluenes. (United States)

    Liu, Guiyan; Yi, Maocong; Liu, Lu; Wang, Jingjing; Wang, Jianhui


    A highly efficient one-pot procedure for the preparation of substituted quinolines from substituted o-nitrotoluenes with electron-withdrawing groups and olefins (acrylic esters and acrylonitriles) using a cesium catalyst has been developed. A plausible [2+4] cycloaddition mechanism is proposed. This method uses nitroaromatic compounds as the starting materials to give quinoline derivatives in good to high yields under mild conditions with no transition metal catalysis. It provides an atom economical pathway for the synthesis of quinoline derivatives which could be used in industrial processes.

  15. Crosslinked wholly aromatic polyether membranes based on quinoline derivatives and their application in high temperature polymer electrolyte membrane fuel cells (United States)

    Kallitsis, K. J.; Nannou, R.; Andreopoulou, A. K.; Daletou, M. K.; Papaioannou, D.; Neophytides, S. G.; Kallitsis, J. K.


    An AB type difunctional quinoline based monomer bearing a pentafluorophenyl unit combined with a phenol functionality is being synthesized and homopolymerized to create linear aromatic polyethers as polymer electrolytes for HT-PEM FCs applications. Several conditions are tested for the optimized synthesis of the monomer and homopolymer. Additionally, covalent crosslinking through aromatic polyether bond formation enables the creation of wholly aromatic crosslinked polymeric electrolyte membranes. More specifically, the perfluorophenyl units are crosslinked with other hydroxyl end functionalized moieties, providing membranes with enhanced chemical and mechanical properties that are moreover easily doped with phosphoric acid even at ambient temperatures. All membranes are evaluated for their structural and thermal characteristics and their doping ability with phosphoric acid. Selected crosslinked membranes are further tested in terms of their single cell performance at the temperature range 160 °C-200 °C showing promising performance and high conductivity values even up to 0.2 S cm-1 in some cases.

  16. Reinvestigation of bromination of 8-substituted quinolines and synthesis of novel phthalonitriles

    Directory of Open Access Journals (Sweden)

    Salih Ökten


    Full Text Available Bromination of a series of 8-substituted quinolines was reinvestigated and specified for optimum yields and isolation conditions. Mono bromination of 8-hydroxyquinoline ( 2a and 8-aminoquinoline ( 2c gave mixture of mono and dibromo derivatives 5,7-dibromo-8-hydroxyquinoline ( 3a ,5,7-dibromo-8-aminoquinoline (3c, 7-bromo-8-hydroxyquinoline (3d, 5-bromo-8-aminoquinoline (3ewhile 8-methoxy quinoline ( 2b furnished 5-bromo-8-methoxyquinoline ( 3f as sole product. N ovel phthalonitrile s, 4-(quinolin-8-yloxyphthalonitrile ( 6 and 4-chloro-5-(quinolin-8-yloxyphthalonitrile (8 of 8-hydroxyquinoline ( 2a were synthesized and converted into their respective bromo derivatives 4-(5-bromoquinolin-8-yloxyphthalonitrile ( 7 and4-((5-bromoquinolin-8-yloxy-5-chlorophthalonitrile (9 .

  17. Coordination chemistry and biological activity of 5'-OH modified quinoline-B12 derivatives. (United States)

    Zelenka, Karel; Brandl, Helmut; Spingler, Bernhard; Zelder, Felix


    The consequences of structural modifications at the 5'-OH ribofuranotide moiety of quinoline modified B12 derivatives are discussed in regard of the coordination chemistry, the electrochemical properties and the biological behaviour of the compound.

  18. The potential of quinoline derivatives for the treatment of Toxoplasma gondii infection. (United States)

    Kadri, Dema; Crater, Anna K; Lee, Hoyun; Solomon, V Raja; Ananvoranich, Sirinart


    Here we reported our investigation, as part of our drug repositioning effort, on anti-Toxoplasma properties of newly synthesized quinoline compounds. A collection of 4-aminoquinoline and 4-piperazinylquinoline analogs have recently been synthesized for use in cancer chemotherapy. Some analogs were able to outperform chloroquine, a quinoline derivative drug which is commonly used in the treatment of malaria and other parasitic infections. Herein 58 compounds containing one or two quinoline rings were examined for their effectiveness as potential anti-Toxoplasma compounds. Of these 58 compounds, 32 were efficient at inhibiting Toxoplasma growth (IC50Toxoplasma effect among quinoline derivatives was detected in B11, B12, B23, and B24, whose structures carry two quinoline rings, and their resultant cLogP values are ⩾7. Among these compounds, B23 was the most effective compound with IC50 value of 425±35 nM, and TI value of 4.9. It was also noted that compounds with at least one quinoline ring, displaying anti-Toxoplasma effects were capable of causing the disappearance of the apicoplast, a plastid-like organelle. When treated with quinoline, 8-hydroxyquinoline or B23, 40-45% of the parasites lost their apicoplasts. Our findings recapitulate the properties of quinoline derivatives in diminishing apicoplast. This could aid further investigations of anti-parasitic treatments specific to Apicomplexan. More importantly, B12 and B23 which harbor superior anti-cancer properties than chloroquine, have effective anti-Toxoplasma activity. These compounds therefore have significant potential for future development of chemotherapeutic agents for patients suffering from breast cancers and parasitic infection. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Crystal Structure of the Homo sapiens Kynureninase-3-Hydroxyhippuric Acid Inhibitor Complex: Insights into the Molecular Basis Of Kynureninase Substrate Specificity

    Energy Technology Data Exchange (ETDEWEB)

    Lima,Santiago; Kumar,Sunil; Gawandi,Vijay; Momany,Cory; Phillips,Robert S.; (Georgia)


    Homo sapiens kynureninase is a pyridoxal-5'-phosphate dependent enzyme that catalyzes the hydrolytic cleavage of 3-hydroxykynurenine to yield 3-hydroxyanthranilate and L-alanine as part of the tryptophan catabolic pathway leading to the de novo biosynthesis of NAD{sup +}. This pathway results in quinolinate, an excitotoxin that is an NMDA receptor agonist. High levels of quinolinate have been correlated with the etiology of neurodegenerative disorders such as AIDS-related dementia and Alzheimer's disease. We have synthesized a novel kynureninase inhibitor, 3-hydroxyhippurate, cocrystallized it with human kynureninase, and solved the atomic structure. On the basis of an analysis of the complex, we designed a series of His-102, Ser-332, and Asn-333 mutants. The H102W/N333T and H102W/S332G/N333T mutants showed complete reversal of substrate specificity between 3-hydroxykynurenine and L-kynurenine, thus defining the primary residues contributing to substrate specificity in kynureninases.

  20. Heterocycles [h]-Fused Onto 4-Oxoquinoline-3-Carboxylic Acid, Part VIII [1]. Convenient Synthesis and Antimicrobial Properties of Substituted Hexahydro[1,4]diazepino[2,3-h]quinoline-9-carboxylic acid and Its Tetrahydroquino[7,8-b]benzodiazepine Analog

    Directory of Open Access Journals (Sweden)

    Yusuf M. Al-Hiari


    Full Text Available [1,4]Diazepino[2,3-h]quinolone carboxylic acid 3 and its benzo-homolog tetrahydroquino[7,8-b]benzodiazepine-3-carboxylic acid 5 were prepared via PPAcatalyzed thermal lactamization of the respective 8-amino-7-substituted-1,4-dihydroquinoline-3-carboxylic acid derivatives 8, 10. The latter compounds were obtained by reduction of their 8-nitro-7-substituted-1,4-dihydroquinoline-3-carboxylic acid precursors 7, 9 which, in turn, were prepared by reaction of 7-chloro-1-cyclopropyl-6-fluoro-8-nitro-1,4-dihydroquinoline-3-carboxylic acid (6 with each of β-alanine and anthranilic acid. All intermediates and target compounds were characterized using elemental analysis, NMR, IR and MS spectral data. The prepared targets and the intermediates have shown interesting antibacterial activity mainly against Gram positive strains. In particular, compound 8 showed good activity against S. aureus (MIC = 0.39 μg/mL and B. subtilis (MIC = 0.78 μg/mL. Compounds 5a and 9 have also displayed good antifungal activity against C. albicans (MIC = 1.56 μg/mL and 0.78 μg/mL, respectively. None of the compounds tested showed any anticancer activity against solid breast cancer cell line MCF-7 cells or a human breast adenocarcinoma cell line.

  1. Quinolines in clothing textiles--a source of human exposure and wastewater pollution? (United States)

    Luongo, Giovanna; Thorsén, Gunnar; Ostman, Conny


    A production process in which the use of various types of chemicals seems to be ubiquitous makes the textile industry a growing problem regarding both public health as well as the environment. Among several substances used at each stage, the present study focuses on the quinolines, a class of compounds involved in the manufacture of dyes, some of which are skin irritants and/or classified as probable human carcinogens. A method was developed for the determination of quinoline derivatives in textile materials comprising ultrasound-assisted solvent extraction, solid phase extraction cleanup, and final analysis by gas chromatography/mass spectrometry. Quinoline and ten quinoline derivatives were determined in 31 textile samples. The clothing samples, diverse in color, material, brand, country of manufacture, and price, and intended for a broad market, were purchased from different shops in Stockholm, Sweden. Quinoline, a possible human carcinogen, was found to be the most abundant compound present in almost all of the samples investigated, reaching a level of 1.9 mg in a single garment, and it was found that quinoline and its derivatives were mainly correlated to polyester material. This study points out the importance of screening textiles with nontarget analysis to investigate the presence of chemicals in an unbiased manner. Focus should be primarily on clothing worn close to the body.

  2. CO2 binding in the (quinoline-CO2)- anionic complex (United States)

    Graham, Jacob D.; Buytendyk, Allyson M.; Wang, Yi; Kim, Seong K.; Bowen, Kit H.


    We have studied the (quinoline-CO2)- anionic complex by a combination of mass spectrometry, anion photoelectron spectroscopy, and density functional theory calculations. The (quinoline-CO2)- anionic complex has much in common with previously studied (N-heterocycle-CO2)- anionic complexes both in terms of geometric structure and covalent bonding character. Unlike the previously studied N-heterocycles, however, quinoline has a positive electron affinity, and this provided a pathway for determining the binding energy of CO2 in the (quinoline-CO2)- anionic complex. From the theoretical calculations, we found CO2 to be bound within the (quinoline-CO2)- anionic complex by 0.6 eV. We also showed that the excess electron is delocalized over the entire molecular framework. It is likely that the CO2 binding energies and excess electron delocalization profiles of the previously studied (N-heterocycle-CO2)- anionic complexes are quite similar to that of the (quinoline-CO2)- anionic complex. This class of complexes may have a role to play in CO2 activation and/or sequestration.

  3. Determination of aniline and quinoline compounds in textiles. (United States)

    Luongo, Giovanna; Iadaresta, Francesco; Moccia, Emanuele; Östman, Conny; Crescenzi, Carlo


    A simple method for simultaneous determination of twenty-one analytes, belonging to two classes of compounds, aromatic amines and quinolines, is presented. Several of the analytes considered in this study frequently occur in textiles goods on the open market and have been related to allergic contact dermatitis and/or are proven or suspected carcinogens. The method includes an efficient clean-up step using graphitized carbon black (GCB) that simplifies and improves the robustness of the subsequent GC-MS analysis. Briefly, after solvent extraction of the textile sample, the extract is passed through a GCB SPE cartridge that selectively retain dyes and other interfering compounds present in the matrix, producing a clean extract, suitable for GC-MS analysis, is obtained. The method was evaluated by spiking blank textiles with the selected analytes. Method quantification limits (MQL) ranged from 5 to 720ng/g depending on the analyte. The linear range of the calibration curves ranged over two order magnitude with coefficients of determination (R(2)) higher than 0.99. Recoveries ranged from 70 to 92% with RSDs 1.7-14%. The effectiveness of the method was tested on a variety of textile materials samples from different origin. In a pilot explorative survey, 2,6-dichloro-4-nitroaniline was detected in all the analysed clothing samples in concentrations ranging from 1.0 to 576μg/g. 2,4-dinitroaniline was detected in four of the seven samples with a highest concentration of 305μg/g. Quinoline was detected in all samples in concentrations ranging from 0.06 to 6.2μg/g. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Quinoline based furanones and their nitrogen analogues: Docking, synthesis and biological evaluation

    Directory of Open Access Journals (Sweden)

    Sukhbir Lal Khokra


    Full Text Available A small library of twenty-four quinoline based butenolides also known as furanones and their nitrogen analogues was prepared by using two different aroylpropionic acids, viz. 3-(2-naphthoylpropionic acid (3 and 3-(biphenyl-4-ylpropionic acid (4, as starting materials. The 3-aroylpropionic acids were reacted with different 6-substituted-2-chloroquinolin-3-carbaldehydes (2a–d to obtain the corresponding furan-2(3H-ones (5a–h. The purified and characterized furanones were then converted into their corresponding 2(3H-pyrrolones (6a–h and N-benzyl-pyrrol-2(3H-ones (7a–h. The antimicrobial activities of the title compounds were evaluated against two strains of each Gram +ve (Staphylococcus aureus and Bacillus subtilis, Gram −ve bacteria (Escherichia coli and Pseudomonas aeruginosa and against fungal strains of Aspergillus niger and Aspergillus flavus. In vivo anti-inflammatory potential of the title compounds was investigated by standard method. Majority of the compounds showed significant antibacterial activity against both the Gram +ve strains. Eight most potent anti-inflammatory compounds (5b, 5d, 5h, 6b, 7b, 7d, 7f, 7h which exhibited >53% inhibition in edema, were also screened for their in vivo analgesic activity. All the tested compounds were found to have significant reduction in ulcerogenic action but only three compounds (5d, 5h and 7h showed comparable analgesic activity to standard drug, diclofenac. The results were also validated using in silico approach and maximum mol doc score was obtained for compounds 7a–h. On comparing the in vivo and in silico anti-inflammatory results of synthesized compounds, N-benzyl pyrrolones (7a–h emerged as the potent anti-inflammatory agents. It was also observed that compounds that possess electron withdrawing group such as Cl or NO2 are more biologically active.

  5. Determination of three physical properties of quinoline ionic liquids with hexafluorophosphate

    Directory of Open Access Journals (Sweden)

    Tang Dan


    Full Text Available Densities of one acidic ionic liquid (IL Quinolinum hexafluorophosphate ([HBpy][PF6], and four neutral dicationic ionic liquids (ILs based on quinoline and hexafluoro-phosphate and linked with poly(ethylene glycol (PEG: ([PEG200-DIL][PF6]2, [PEG400-DIL][PF6]2, [PEG800-DIL][PF6]2 and [PEG1000-DIL][PF6]2 were determined. In addition, the solubilities of six ILs in six lower alcohols, water, acetonitrile and diethyl ether were measured at 288.15 K; and the hydroscopicity of above five ILs were measured at the temperature of 298.15 K and relative humidity of 79% for 24 h. Densities of five ionic liquids were determined between 283.15 and 333.15 K. Then the densities of five binary system (ILs/acetonitrile were explored between 283.15 and 333.15 K, the type of the ionic liquid, the concentration of five ILs in CH3CN, and the effect of temperature on the binary systems, were correlated with the measured data.

  6. Effects of impregnation methods and drying conditions on quinoline hydrodenitrogenation over Ni-W based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Fang; Qiu, Zegang; Zhao, Liangfu; Xiang, Hongwei [Institute of Coal Chemistry, Chinese Academy of Sciences (China); Guo, Shaoqing [Taiyuan University of Science and Technology (China)


    The effects of impregnation methods (co-impregnation and sequential impregnation) and drying conditions (air and vacuum) on the structure and catalytic behavior of MCM-41 supported Ni-W catalysts were investigated. The catalysts were characterized by powder X-ray diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance UV-Vis absorbance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and pyridine adsorbed infrared spectroscopy (Py-IR) techniques. They were tested for hydrodenitrogenation (HDN) of quinoline at temperatures of 300-400 deg C. The HDN results showed that the catalysts prepared by co-impregnation were more active than the catalysts prepared by sequential impregnation and the catalysts prepared by drying under vacuum were more active than the catalysts dried in air. Characterization revealed that the co-impregnation method and drying under vacuum promoted the dispersion of W, the formation of the active phases, and the formation of acidic sites on the catalysts. (author)

  7. A quinoline-based fluorometric and colorimetric dual-modal pH probe and its application in bioimaging (United States)

    Zhu, Qin; Li, Zhao; Mu, Lan; Zeng, Xi; Redshaw, Carl; Wei, Gang


    The compound (E)-8-hydroxyl-2-[(E)-2-(2, 4-dihydroxyphenyl)vinyl]-quinoline (1) has been developed as a fluorometric and colorimetric dual-modal probe for pH detection in solution and in vivo. Remarkable changes in the fluorescence intensity with large Stokes shifts and colorimetric responses were observed as a function of pH. The sensing mechanisms involving protonation and deprotonation processes over the acidic and alkaline pH ranges were confirmed by 1H NMR and IR spectroscopic analysis. Furthermore, the application of probe 1 for the imaging of live PC3 cells was successfully achieved. Test strips based on probe 1 were fabricated, and were found to act as a convenient and efficient pH test kits.

  8. Metal(II) complexes synthesized based on quinoline-2,3-dicarboxylate as electrocatalysts for the degradation of methyl orange. (United States)

    Gong, Yun; Zhang, Miao Miao; Qin, Jian Bo; Li, Jian; Meng, Jiang Ping; Lin, Jian Hua


    Based on quinoline-2,3-dicarboxylic acid (H2L), two metal(II) complexes formulated as MnL(phen)(H2O)·H2O (phen = 1,10-phenanthroline) (1) and Co(HL)2(PPA)·4H2O (PPA = N(1),N(4)-di(pyridin-4-yl)terephthalamide) (2) were synthesized and structurally characterized by single-crystal X-ray diffraction. Both complexes 1 and 2 exhibit one-dimensional (1D) chain-like structures, in which stable five-membered rings are observed. Different chains are linked by strong π-π stacking interactions into a three-dimensional (3D) supramolecular architecture. Both complexes can increase the degradation rate of methyl orange (MO), which is expected to be associated with their electrocatalytic activities for the H2 evolution reaction from water.

  9. Synthesis of quinoxalines or quinolin-8-amines from N-propargyl aniline derivatives employing tin and indium chlorides. (United States)

    Aichhorn, Stefan; Himmelsbach, Markus; Schöfberger, Wolfgang


    Pyrazino compounds such as quinoxalines are 1,4-diazines with widespread occurrence in nature. Quinolin-8-amines are isomerically related and valuable scaffolds in organic synthesis. Herein, we present intramolecular main group metal Lewis acid catalyzed formal hydroamination as well as hydroarylation methodology using mono-propargylated aromatic ortho-diamines. The annulations can be conducted utilizing equal aerobic conditions with either stannic chloride or indium(iii) chloride and represent primary examples for main group metal catalyzed 6-exo-dig and 6-endo-dig, respectively, cyclizations in such settings. Both types of reactions can also be utilized in a one-pot manner starting from ortho-nitro N-propargyl anilines using stoichiometric amounts SnCl2·2H2O or In powder. Mechanistic considerations are presented regarding the substituent-depending regioselectivity.

  10. N-{4-[(2E-3-(2H-1,3-Benzodioxol-5-ylprop-2-enoyl]phenyl}quinoline-3-carboxamide

    Directory of Open Access Journals (Sweden)

    Efrain Polo


    Full Text Available An amide chalconehas been synthesized in a two-step reaction. First, N-(4-acetylphenylquinoline-3-carboxamide 2 was synthesized by the reaction of quinoline-3-carboxylic acid 1 and thionyl chloride (SOCl2, following the addition of 4-aminoacetophenone. Then, a typical Claisen–Schmidtreactionwas made between 2 and piperonal using KOH solution as a catalystin ethanol, under ultrasonic irradiation. The structure of the target compound was established by FTIR (Fourier-transform infrared spectroscopy, HRMS, 1H and 13C-NMR.

  11. Mineralization of Quinoline by BDD Anodes: Variable Effects and Its Effluent Characteristics

    Directory of Open Access Journals (Sweden)

    C. R. Wang


    Full Text Available BDD anodes were selected for quinoline mineralization and influence of operating parameters, such as current density, initial quinoline concentration, supporting electrolyte, and initial pH was investigated. Based on the consideration of quinoline removal efficiency and average current efficiency, at initial quinoline concentration of 50 mg L−1 and pH of 7, the optimal condition was confirmed as current density of 75 mA cm−2, electrolysis time of 1.5 h, and Na2SO4 concentration of 0.05 mol L−1 by orthogonal test. At different electrolysis time, its effluent characteristics were focused on. The biodegradability (the ratio between BOD5 and COD was enhanced from initial 0.02 to 0.57 at 90 min. The specific oxygen uptake rate was used to assess effluent toxicity, and the value gradually reduced with decreasing effluent organic concentration with mean value of 5.51, 4.19, and 2.20 mgO2 g−1MLSS at electrolysis time of 15, 30, and 45 min, respectively. Compared with control sample (prepared with glucose, the effluent of quinoline mineralization showed obvious inhibition effect on microorganisms at electrolysis time of 15 min, and then it was significantly faded at 30 min and 45 min.

  12. An Efficient Synthesis of Substituted Quinolines via Indium(III) Chloride Catalyzed Reaction of Imines with Alkynes

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Mei; Fu, Weijun; Xun, Chen [Luoyang Normal University, Luoyang (China); Zou, Guanglong [Guizhou University for Nationalities, Guiyang (China)


    An efficient synthetic method for the preparation of quinolines through indium(III) chloride-catalyzed tandem addition-cyclization-oxidation reactions of imines with alkynes was developed. The processes can provide a diverse range of quinoline derivatives in good yields from simple imines and alkynes.

  13. The cosmetic dye quinoline yellow causes DNA damage in vitro. (United States)

    Chequer, Farah Maria Drumond; Venâncio, Vinícius de Paula; de Souza Prado, Maíra Rocha; Campos da Silva e Cunha Junior, Luiz Raimundo; Lizier, Thiago Mescoloto; Zanoni, Maria Valnice Boldrin; Rodríguez Burbano, Rommel; Bianchi, Maria Lourdes Pires; Antunes, Lusânia Maria Greggi


    Quinoline yellow (QY) is a chinophthalon derivative used in cosmetic compositions for application to the skin, lips, and/or body surface. However, regulatory data about the genotoxicity and/or mutagenicity of this compound are still controversial. Therefore, this work evaluated the genotoxicity of QY using the comet assay and the cytokinesis-block micronucleus cytome assay (CBMN-Cyt) in the metabolically competent cell line HepG2, which closely mimics phase I metabolism. This research also identified the products formed after electrochemical oxidation of the QY dye, which simulates hepatic biotransformation. The primary products generated after the oxidation process were analyzed by High Performance Liquid Chromatography coupled with a Diode Array Detector (HPLC/DAD), which detected the production of 4,4'-diaminodiphenylmethane, 2-methoxy-5-methylaniline and 4,4'-oxydianiline. The results demonstrated that low (from 0.5 to 20 μg mL(-1)) QY concentrations were genotoxic in HepG2 cells on both assays and those harmful compounds were detected after the oxidation process. Our findings suggest that this colorant could cause harmful effects to humans if it is metabolized or absorbed through the skin. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Synthesis, Antibacterial and Antioxidant Evaluation of Novel 1-(5,7-Dichloro-1,3-benzoxazol-2-yl-1H-pyrazolo[3,4-b]quinoline Derivatives

    Directory of Open Access Journals (Sweden)

    N. D. Jayanna


    Full Text Available Some novel 1-(5,7-dichloro-1,3-benzoxazol-2-yl-1H-pyrazolo[3,4-b]quinoline derivatives 8(a–f were synthesized by reacting 5,7-dichloro-2-hydrazino-1,3-benzoxazole 4 and substituted-2-chloro-3-quinoline carbaldehydes using p-toluenesulfonic acid (PTSA as a catalyst for the cyclisation. The target molecules have been characterized by IR, 1H NMR, 13C NMR, and mass spectral studies. The synthesized compounds were screened for biological activities, and some of the compounds have exhibited encouraging antibacterial and antioxidant activities. The compounds 8a and 8e showed potent antibacterial activity, whereas the compounds 8e and 8f act as antioxidants.

  15. Evaluation of (4-aminobutyloxy)quinolines as a novel class of antifungal agents. (United States)

    Vandekerckhove, Stéphanie; Tran, Hai Giang; Desmet, Tom; D'hooghe, Matthias


    Antifungal assessment of eighteen 5-, 6- and 8-(4-aminobutyloxy)quinolines revealed a significant susceptibility of the tested fungi and yeast strains (Candida albicans, Rhodotorula bogoriensis, Aspergillus flavus and Fusarium solani) toward different halo-substituted 8-(4-aminobutyloxy)quinolines. The six most potent compounds displayed antifungal activities similar to those of established antifungal agents such as Amphotericin B, Fluconazole and Itraconazole, and one representative also showed a promising broad-spectrum antifungal profile. The introduction of an aminoalkoxy side chain at the 8-position of a halo-substituted quinoline core might thus provide a new class of lead structures in the search for novel antifungal agents. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Novel quinolines carrying pyridine, thienopyridine, isoquinoline, thiazolidine, thiazole and thiophene moieties as potential anticancer agents

    Directory of Open Access Journals (Sweden)

    Ghorab Mostafa M.


    Full Text Available As a part of ongoing studies in developing new anticancer agents, novel 1,2-dihydropyridine 4, thienopyridine 5, isoquinolines 6–20, acrylamide 21, thiazolidine 22, thiazoles 23–29 and thiophenes 33–35 bearing a biologically active quinoline nucleus were synthesized. The structure of newly synthesized compounds was confirmed on the basis of elemental analyses and spectral data. All the newly synthesized compounds were evaluated for their cytotoxic activity against the breast cancer cell line MCF7. 2,3-Dihydrothiazole-5-carboxamides 27, 25, 4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (34, 1,2-dihydroisoquinoline-7-carbonitrile (7, 5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene-3-carboxamide (35, 1,2-dihydroisoquinoline-7-carbonitrile (6, 2-cyano-3-(dimethylamino-N-(quinolin-3-ylacrylamide (21, 1,2-dihydroisoquinoline-7-carbonitriles (11 and (8 exhibited higher activity (IC50 values of 27–45 μmol L–1 compared to doxorubicin (IC50 47.9 μmol L–1. LQ quinolin-3-yl-1,2-dihydroisoquinoline-7-carbonitrile (12, 2-thioxo-2,3-dihydrothiazole-5-carboxamide (28 and quinolin-3-yl-1,2-dihydroisoquinoline-7-carbonitrile (15 show activity comparable to doxorubicin, while (quinolin-3-yl-1,2-dihydroisoquinoline-7-carbonitrile (9, 2,3-dihydrothiazole-5-carboxamide (24, thieno [3,4-c] pyridine-4(5H-one (5, cyclopenta[b]thiophene-3-carboxamide (33 and (quinolin-3-yl-6-stryl-1,2-dihydroisoquinoline-7-carbonitrile (10 exhibited moderate activity, lower than doxorubicin.

  17. 4,4′-Methylenebis{N-[(E-quinolin-2-ylmethylidene]aniline}

    Directory of Open Access Journals (Sweden)

    Daoud Djamel


    Full Text Available The title compound, C33H24N4, was prepared by the reaction of a bifunctional aromatic diamine (4,4′-diaminodiphenylmethane and an aldehyde (quinoline-2-carboxaldhyde. The molecule consists of two nearly planar (or r.m.s. deviation = 0.017 Å 4-methyl-N-[(E-quinolin-2-ylmethylidene]aniline moieties, which are linked by the methylene group. The angle between the mean planes of the two benzene rings connected to the methylene group is 77.86 (11°.

  18. Osmium-mediated direct C–H bond activation at the 8-position of quinolines


    Esteruelas, Miguel A.; Larramona, Carmen; Oñate, Enrique


    Metal-mediated direct C–H bond activation at the 8-position of quinolines, which is the essential step for the functionalization of this bond, is promoted by the hexahydride OsH6(PiPr3)2. This complex activates quinoline and 2-, 3-, 6-, and 7-methylquinoline to afford the classical trihydride derivatives OsH3{κ2-C8,N-(quinolinyl)}(PiPr3)2 and OsH3{κ2-C8,N-(quinolinyl-n-Me)}(PiPr3)2 (n = 2, 3, 6, 7), containing a four-membered heterometalla ring.

  19. Purification of quinoline yellow components using high-speed counter-current chromatography by stepwise increasing the flow-rate of the mobile phase. (United States)

    Oka, Hisao; Harada, Ken-Ichi; Suzuki, Masanao; Fujii, Kiyonaga; Iwaya, Masato; Ito, Yuko; Goto, Tomomi; Matsumoto, Hiroshi; Ito, Yoichiro


    Quinoline yellow (Color Index No. 47005) consists of multiple components that show a large difference in their partition coefficients (K), ranging from 0.03 to 3.3 in the solvent system tert.-butyl methyl ether (MTBE)-1-butanol-acetonitrile-aqueous 0.1 M trifluoroacetic acid (TFA). Consequently, it requires an excessively long elution time for the simultaneous separation of all components by the standard high-speed counter-current chromatography technique, which uses a constant flow-rate of the mobile phase. In order to overcome this problem, we increased the flow-rate of the mobile phase stepwise from 0.1 to 2.0 mL/min. Using this new procedure, six components (0.2-6.1 mg) were successfully isolated from 25 mg of a commercial quinoline yellow preparation in a single run using a two-phase solvent system composed of MTBE-1-butanol-acetonitrile-aqueous 0.1 M TFA (1:3:1:5, v/v). The purified components were analyzed by high-performance liquid chromatography, electrospray ionization mass spectrometry, and nuclear magnetic resonance spectroscopy.

  20. Studies on cluster, salt and molecular complex of zinc-quinolinate

    Indian Academy of Sciences (India)

    127, No. 2, February 2015, pp. 215–223. c Indian Academy of Sciences. DOI 10.1007/s12039-015-0781-6. Studies on cluster, salt and molecular complex of zinc-quinolinate. PRITHIVIRAJ KHAKHLARY and JUBARAJ B BARUAH∗. Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781 039, India.

  1. Emitting oligomer containing quinoline group: Synthesis and photophysical properties of conjugated oligomer obtained by Wittig reaction

    Energy Technology Data Exchange (ETDEWEB)

    Karpagam, S., E-mail: [Organic Chemistry Division, School of Advanced Science, VIT University, Vellore 14, Tamil Nadu (India); Guhanathan, S. [Department of Chemistry, Muthurangam Government Arts College, Vellore, Tamil Nadu (India)


    Dichloro quinoline substituted phenylene vinylene oligomer (QUI-OPV) was synthesized via Wittig route. Formation of the oligomer was characterized by spectral (FTIR, {sup 1}H and {sup 13}C NMR), elemental and gel permeation chromatography analysis. The oligomer possesses excellent thermal stability (decomposition temperature 470 °C), solubility in common organic solvents and high glass transition temperature (61 °C). The morphology of the oligomer film of one dimensional (1D) and three dimensional (3D) architectures was observed using atomic force microscopy (AFM). In CHCl{sub 3} solution, the oligomer showed the absorption maxima at 382 nm and also observed excellent photoluminescence (PL) with bluish green emission maxima at shorter wavelengths of 477 nm. The introduction of quinoline to the main chain resulted in a slight decrease of effective conjugation length and exhibited the blue shift in both the absorption and emission spectra. -- Highlights: • Simple synthesis of quinoline functionalized phenylene vinylene oligomer by Wittig route. • The materials had good organosolubility and intrinsic viscosity. • High thermal stability and good surface roughness morphology were observed. • Performance of luminescence improved via introducing quinoline into PPV. • Electrochemical and optical band gap of the oligomer were consistent with each other.

  2. Chlorine- and Sulphur-substituted Pyrrolo[3,4-b]quinolines and ...

    African Journals Online (AJOL)

    b]quinolin-1(3H)-one .... amount of 3-thioxo derivative 4 in the product mixture. These suppositions derive from the observations with ...... is grateful to the University of the Witwatersrand for financial support. References and Notes. 1 M.A. Khan ...

  3. The washout effect during laundry on benzothiazole, benzotriazole, quinoline, and their derivatives in clothing textiles. (United States)

    Luongo, Giovanna; Avagyan, Rozanna; Hongyu, Ren; Östman, Conny


    In two previous papers, the authors have shown that benzothiazole, benzotriazole, quinoline, and several of their derivatives are widespread in clothing textile articles. A number of these compounds exhibit allergenic and irritating properties and, due to their octanol-water partition coefficient, are prone to be absorbed by the skin. Moreover, they are slightly soluble in water, which could make washing of clothes a route of emission into the environment. In the present study, the washout effect of benzothiazole, benzotriazole, quinoline, and some of their derivatives has been investigated. Twenty-seven textile samples were analyzed before, as well as after five and ten times of washing. The most abundant analyte was found to be benzothiazole, which was detected in 85 % of the samples with an average concentration of 0.53 μg/g (median 0.44 μg/g), followed by quinoline, detected in 81 % of the samples with an average concentration of 2.42 μg/g (median 0.21 μg/g). The average decrease in concentration for benzothiazoles was 50 % after ten times washing, while it was around 20 % for quinolines. The average emission to household wastewater of benzothiazoles and quinolines during one washing (5 kg of clothes made from polyester materials) was calculated to 0.5 and 0.24 g, respectively. These results strongly indicate that laundering of clothing textiles can be an important source of release of these compounds to household wastewater and in the end to aquatic environments. It also demonstrates a potential source of human exposure to these chemicals since considerable amounts of the compounds remain in the clothes even after ten times of washing.

  4. Genetic relationship of organic bases of the quinoline and isoquinoline series from lignite semicoking tars with the initial biological material

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Podshibyakin, S.I.; Domogatskii, V.V.; Shvykin, A.Y.; Shavyrina, O.A.; Chilachava, K.B. [Leo Tolstoy State Pedagog University, Tula (Russian Federation)


    The genetic relationship of quinoline and isoquinoline compounds present in semicoking tars of Kimovsk lignites (near-Moscow fields) with the initial vegetable material is discussed. Transformation pathways of the native compounds in the course of lignite formation are suggested.

  5. Ruthenium-catalysed synthesis of 2- and 3-substituted quinolines from anilines and 1,3-diols

    DEFF Research Database (Denmark)

    Monrad, Rune Nygaard; Madsen, Robert


    A straightforward synthesis of substituted quinolines is described by cyclocondensation of anilines with 1,3-diols. The reaction proceeds in mesitylene solution with catalytic amounts of RuCl3·xH 2O, PBu3 and MgBr2·OEt2. The transformation does not require any stoichiometric additives and only pr...... in a similar fashion as observed in the Doebner-von Miller quinoline synthesis. © 2011 The Royal Society of Chemistry....

  6. Adsorptive removal of indole and quinoline from model fuel using adenine-grafted metal-organic frameworks. (United States)

    Sarker, Mithun; Song, Ji Yoon; Jeong, Ah Rim; Min, Kil Sik; Jhung, Sung Hwa


    A highly porous metal-organic framework (MOF), MIL-101, was modified for the first time with the nucleobase adenine (Ade) by grafting onto the MOF. The Ade-grafted MOF, Ade-MIL-101, was further protonated to obtain P-Ade-MIL-101, and these MOFs were utilized to remove nitrogen-containing compounds (NCCs) (such as indole (IND) and quinoline (QUI)) from a model fuel by adsorption. These functionalized MOFs exhibited remarkable adsorption performance for NCCs compared with that shown by commercial activated carbon (AC) and pristine MIL-101, even though the porosities of the functionalized-MOFs were lower than that of pristine MIL-101. P-Ade-MIL-101 has 12.0 and 10.8 times capacity to that of AC for IND and QUI adsorption, respectively; its adsorption performance was competitive with that of other reported adsorbents. The remarkable adsorption of IND and QUI by Ade-MIL-101 was attributed to H-bonding. H-bonding combined with cation-π interactions was proposed as the mechanism for the removal of IND by P-Ade-MIL-101, whereas acid-base interactions were thought to be responsible for QUI adsorption by P-Ade-MIL-101. Moreover, P-Ade-MIL-101 can be regenerated without any severe degradation and used for successive adsorptions. Therefore, P-Ade-MIL-101 was recommended as an effective adsorbent for fuel purification by adsorptive removal of NCCs. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Insight into the effects of modifying chromophores on the performance of quinoline-based dye-sensitized solar cells (United States)

    Mao, Mao; Wang, Jian-Bo; Liu, Xiu-Lin; Wu, Guo-Hua; Fang, Xia-Qin; Song, Qin-Hua


    A series of organic dyes based on quinoline as an electron-deficient π-linker, were designed and synthesized for dye sensitized solar cells (DSSC) application. These push-pull conjugated dyes, sharing same anchoring group with distinctive electron-rich donating groups such as N,N-diethyl (DEA-Q), 3,6-dimethoxy carbazole (CBZ-Q), bis(4-butoxyphenyl)amine (BPA-Q), were synthesized by Riley oxidation of sbnd CH3 followed by Knoevenagel condensation of the corresponding aldehyde precursors 2a-c with cyanoacrylic acid. The optical, electrochemical, theoretical calculation and photovoltaic properties with these three dyes were systematically investigated. Compared to DEA-Q and CBZ-Q, BPA-Q possesses better light harvesting properties with regard to extended conjugate length, red-shifted intramolecular charge transfer band absorption and broaden light-responsive IPCE spectrum, resulting in a greater short circuit photocurrent density output. BPA-Q also has improved open-circuit voltage due to the apparent large charge recombination resistance. Consequently, assembled with iodine redox electrolytes, the device with BPA-Q achieved the best overall conversion efficiency value of 3.07% among three dyes under AM 1.5G standard conditions. This present investigation demonstrates the importance of various N-substituent chromophores in the prevalent D-π-A type organic sensitizers for tuning the photovoltaic performance of their DSSCs.

  8. Application of N-Quinoline-2-carboxamido-8-aminoquinoline in Fabrication of a Ho(III-PVC Membrane Sensor

    Directory of Open Access Journals (Sweden)

    Hassan Ali Zamani


    Full Text Available The N-quinoline-2-carboxamido-8-aminoquinoline (QCA was used as a suitable ion carrier in the construction of a Ho(III PVC-based membrane sensor. This sensor demonstrated good selectivity and sensitivity towards the holmium ion for a broad variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The proposed electrode exhibits a linear dynamic range between 1.0×10-6 and 1.0×10-2 M, with a near Nernstian slope of 20.4±0.3 mV per decade and a detection limit of 4.2×10-7 M. The best performance was obtained with a membrane composition of 30% poly(vinyl chloride, 56% nitrobenzene, 2% sodium tetraphenyl borate, 10% oleic acid and 2% QCA. The potentiometric response of the constructed electrode is pH independent in the range of 2.4-7.4. The sensor possesses the advantages of short conditioning time, fast response time (∼ 5 s and especially, good selectivity towards transition and heavy metal and some mono, di and trivalent cations. The Ho3+ sensor was successfully applied as an indicator electrode in the potentiometric titration of Ho(III ions with EDTA. The electrode was also used for the determination of Ho3+ ions in mixtures of different ions and the determination of the fluoride ion in mouth wash solutions.

  9. Organocatalytically Generated Donor-Acceptor Cyclopropanes in Domino Reactions. One-Step Enantioselective Synthesis of Pyrrolo[1,2-a]quinolines. (United States)

    Sanchez-Diez, Eduardo; Vesga, Diana L; Reyes, Efraim; Uria, Uxue; Carrillo, Luisa; Vicario, Jose L


    An easy and straightforward procedure has been developed for the synthesis of highly enantioenriched pyrrolo[1,2-a]quinolines through a one-pot process that comprises a domino cyclopropane ring opening/aza-Michael/aldol reaction followed by acid-promoted lactamization. The key feature of the synthetic approach relies on the ability of conveniently functionalized cyclopropaneacetaldehydes to undergo organocatalytic activation by a chiral secondary amine that enables the catalytic generation of a donor-acceptor cyclopropane. This intermediate has the potential to undergo a ring opening that generates an electrophilic α,β-unsaturated iminium ion that subsequently reacts through the already mentioned domino sequence and in which stereochemical information is very efficiently transferred from the amine catalyst to the final products. Moreover, one of the alkoxycarbonyl moieties can be easily removed by standard hydrolysis/decarboxylation, providing access to the target adducts as single stereoisomers.

  10. Synthesis and caspase-3 inhibitory activity of 8-sulfonyl-1,3-dioxo-2,3-dihydro-1H-pyrrolo[3,4-c]quinolines. (United States)

    Kravchenko, Dmitri V; Kysil, Volodymyr M; Tkachenko, Sergey E; Maliarchouk, Sergey; Okun, Ilya M; Ivachtchenko, Alexandre V


    A convenient synthesis of novel 8-sulfonyl-1,3-dioxo-4-methyl-2,3-dihydro-1H-pyrrolo[3,4-c]quinolines is described. As key steps to assemble the target molecular scaffold, our method features (a) Pfitzinger reaction of isatin-5-sulfonate 1 with methyl 3-oxo-3-phenylpropanoate, (b) formation of 1-(1H-pyrazol-4-yl)-1H-pyrrole-2,5-dione intermediate 5, and (c) reaction of sulfinic acid 9 with acrylate or methylacrylate leading to the corresponding sulfonyl propionates. Two compounds, ester 11 and morpholide 13, have been identified as potent inhibitors of caspase-3 with IC50 = 6 nM. Our primary data suggest noncompetitive and reversible character of caspase-3 inhibition.

  11. Syntheses and anti-microbial evaluation of new quinoline scaffold derived pyrimidine derivatives

    Directory of Open Access Journals (Sweden)

    Shikha S. Dave


    Full Text Available A series of diversely substituted chalcones derived from a quinoline scaffold, e.g. (E-3-(2-chloroquinolin-3-yl-1-(2-hydroxyphenyl prop-2-en-1-one and its pyrimidine analogues e.g. 2-[2-amino-6-(2-chloroquinolin-3-yl-5,6-dihydropyrimidin-4-yl]phenols have been prepared by condensation of 2-chloro-3-formyl quinoline with differently substituted 2-hydroxy acetophenones and further treatment with guanidine carbonate. All the newly synthesized compounds have been evaluated for their in vitro growth inhibitory activity against Escherichia coli, Pseudomonas vulgaris, Bacillus subtilis, Staphylococcus aureus, Staphylococcus typhi, Candida albicans, Aspergillus niger and Pseudomonas chrysogenum.

  12. Tetrakis(quinolin-8-olato-κ2N,Ohafnium(IV toluene disolvate

    Directory of Open Access Journals (Sweden)

    Maryke Steyn


    Full Text Available In the title compound, [Hf(C9H6NO4]·2C7H8, the hafnium metal centre is coordinated by four N,O-donating bidentate quinolin-8-olate ligands arranged to give a square-antiprismatic coordination polyhedron with a slightly distorted dodecahedral geometry. The average Hf—O and Hf—N distances are 2.096 (3 and 2.398 (3 Å, respectively, and the average O—Hf—N bite angle is 70.99 (11°. The crystal packing is controlled by π–π interactions between quinoline ligands of neighbouring molecules and hydrogen-bonding interactions. The interplanar distances vary between 3.138 (1 and 3.208 (2 Å, while the centroid–centroid distances range from 3.576 (1 to 4.074 (1 Å.

  13. 7-Chloro-4-[(E-2-(4-methoxybenzylidenehydrazin-1-yl]quinoline monohydrate

    Directory of Open Access Journals (Sweden)

    Edward R. T. Tiekink


    Full Text Available The organic molecule in the title hydrate, C17H14ClN3O·H2O, has a small but significant twist from planarity, as seen in the dihedral angle of 12.10 (17° between the quinoline and benzene rings. The conformation about the C=N bond is E. Chains along the b axis are formed in the crystal structure aided by water–quinoline O—H...N (× 2 and hydrazone–water N—H...O hydrogen bonds. Layers of these chains stack along the a axis via C—H...π and π–π interactions [ring centroid–ring centroid distance = 3.674 (2 Å]. C—H...O interactions are also present.

  14. 8-[(3-Phenyl-1,2,4-oxadiazol-5-ylmethoxy]quinoline monohydrate

    Directory of Open Access Journals (Sweden)

    Shu-Yuan Bai


    Full Text Available In the title compound, C18H13N3O2·H2O, the oxadiazole ring forms dihedral angles 7.21 (10 and 21.25 (11° with the quinoline and benzene rings, respectively. The crystal structure features O—H...N hydrogen bonds and is further consolidated by C—H...O hydrogen-bonding interactions involving the water molecule of hydration.

  15. Diiodido[methyl 2-(quinolin-8-yloxyacetate-κN]mercury(II

    Directory of Open Access Journals (Sweden)

    Yu-Hong Wang


    Full Text Available In the title mononuclear complex, [HgI2(C12H11NO3], the HgII ion has a distorted trigonal–planar coordination sphere defined by two I− anions and the N atom of a methyl 2-(quinolin-8-yloxyacetate ligand. In the crystal, face-to-face π–π stacking interactions, with a centroid–centroid distance of 3.563 (9 Å, are observed.

  16. One-pot synthesis of quinoline-based tetracycles by a tandem three-component reaction. (United States)

    Che, Chao; Xiang, Jing; Wang, Guo-Xin; Fathi, Reza; Quan, Jun-Min; Yang, Zhen


    A practical one-pot synthetic strategy for the efficient synthesis of a range of structurally interesting and bioactive quinoline-based tetracycles has been developed. A key step in the synthesis is a tandem three-component reaction of heteroaromatic amine, methyl 2-formylbenzoate and (t)butyl isonitrile, followed by TFA-mediated lactamization via intramolecular aminolysis of an adjacent ester. Results related to a kinase-panel screening for several selected compounds are also discussed in this article.

  17. Supramolecular spectral studies on metal-ligand bonding of novel quinoline azodyes (United States)

    Diab, M. A.; El-Sonbati, A. Z.; El-Bindary, A. A.; Barakat, A. M.


    A series of novel bidentate azodye quinoline ligands were synthesized with various p-aromatic amines like p-(OCH3, CH3, H, Cl and NO2). All ligands and their complexes have been characterized on the basis of elemental analysis, IR, 1H and 13C NMR data and spectroscopic studies. IR and 1H NMR studies reveal that the ligands (HLn) exists in the tautomeric azo/hydrazo form in both states with intramolecular hydrogen bonding. The ligands obtained contain Ndbnd N and phenolic functional groups in different positions with respect to the quinoline group. IR spectra show that the azo compounds (HLn) act as monobasic bidentate ligand by coordinating via the azodye (sbnd Ndbnd Nsbnd ) and oxygen atom of the phenolic group. The ESR (g|| and g⊥) and bonding α2 parameters of the copper ion were greatly affected by substituting several groups position of ring of quinoline and p-aromatic ring. The ESR spectra of copper complexes in powder form show a broad signal with values in order g|| > g⊥ > ge > 2.0023. The value of covalency factor β and orbital reduction factor K accounts for the covalent nature of the complexes. All complexes possessed an octahedral and square planar geometry. The thermal properties of the complexes were investigated using TGA and DSC. It is found that the change of substituent affects the thermal properties of complexes.

  18. Docking studies on the binding of quinoline derivatives and hematin to Plasmodium falciparum lactate dehydrogenase. (United States)

    Cortopassi, Wilian A; Oliveira, Aline A; Guimarães, Ana P; Rennó, Magdalena N; Krettli, Antoniana U; França, Tanos C C


    The literature has reported that ferriprotoporphyrin IX (hematin) intoxicates the malarial parasite through competition with NADH for the active site of the enzyme lactate dehydrogenase (LDH). In order to avoid this, the parasite polymerizes hematin to hemozoin. The quinoline derivatives are believed to form complexes with dimeric hematin, avoiding the formation of hemozoin and still inhibiting LDH. In order to investigate this hypothesis we calculated the docking energies of NADH and some quinoline derivatives (in the free forms and in complex with dimeric hematin) in the active site of the Plasmodium falciparum LDH (PfLDH). Ours results showed better docking score values to the complexes when compared to the free compounds, pointing them as more efficient inhibitors of Pf_LDH. Further we performed Molecular Dynamics (MD) simulations studies on the best docking conformation of the complex chloroquine-dimeric hematin with PfLDH. Our in silico results corroborate experimental data suggesting a possible action route for the quinoline derivatives in the inhibition of PfLDH.

  19. Dimethylurea/citric acid as a highly efficient deep eutectic solvent for ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 126; Issue 3. Dimethylurea/citric acid ... Dimethylurea/citric acid deep eutectic solvent was used as a dual catalyst and a green reaction medium for the efficient synthesis of bis(indolyl)methanes, quinolines and aryl-4, 5-diphenyl-1H-imidazoles. Ease of recovery and ...

  20. An expeditious I sub(2)-catalyzed entry into 6H-indolo[2,3-b]quinoline system of cryptotackieine

    Digital Repository Service at National Institute of Oceanography (India)

    Parvatkar, P.T; Parameswaran, P.S.; Tilve, S.G.

    A synthesis of a series of novel 6H-indolo[2,3-b]- quinolines with different substituents on the quinoline ring is described. The method involves reaction of indole-3-carboxyaldehyde with aryl amines in the presence of a catalytic amount of iodine...

  1. Crystal structure of bis(azido-κNbis(quinolin-8-amine-κ2N,N′iron(II

    Directory of Open Access Journals (Sweden)

    Fatima Setifi


    Full Text Available The search for new molecular materials with interesting magnetic properties using the pseudohalide azide ion and quinolin-8-amine (aqin, C9H8N2 as a chelating ligand, led to the synthesis and structure determination of the title complex, [Fe(N32(C9H8N22]. The complex shows an octahedral geometry, with the FeII atom surrounded by six N atoms; the two N3− anions coordinate in a cis configuration, while the remaining N atoms originate from the two quinolin-8-amine ligands with the quinoline N atoms lying on opposite sides of the Fe atom. The crystal packing is dominated by layers of hydrophilic and aromatic regions parallel to the ac plane, stabilized by a two-dimensional hydrogen-bonded network and π–π stacking.

  2. Quinoline alkaloids and friedelane-type triterpenes isolated from leaves and wood of Esenbeckia alata kunt (Rutaceae

    Directory of Open Access Journals (Sweden)

    Luis Enrique Cuca-Suarez


    Full Text Available This work describes the phytochemical exploration of the ethanol extract from leaves and wood of Esenbeckia alata, leading to the isolation and identification of quinoline alkaloids 4-methoxy-3-(3'-methyl-but-2'-enyl-N-methyl-quinolin-2(1 H-one, N-methylflindersine, dictamine, kokusaginine, Γ-fagarine, flindersiamine, as well as the fridelane-type triterpenes, frideline, fridelanol and its acetate derivative. Identification of these compounds was based on full analyses of spectroscopic data (¹H, 13C, 1D, 2D, IR, MS and comparison with data reported in literature. Compound 4-methoxy-3-(3'-methyl-but-2'-enyl-N-methyl-quinolin-2(1 H-one is reported for the first time for the genus Esenbeckia.

  3. Quinoline alkaloids and friedelane-type triterpenes isolated from leaves and wood of Esenbeckia alata Kunt (Rutaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Cuca-Suarez, Luis Enrique; Barrera, Ericsson David Coy [Universidad Nacional de Colombia, Bogota (Colombia). Dept. de Quimica; Alvarez Caballero, Juan Manuel [Universidad del Magdalena, Santa Marta DTCH (Colombia). Facultad de Ciencias Basicas


    This work describes the phytochemical exploration of the ethanol extract from leaves and wood of Esenbeckia alata, leading to the isolation and identification of quinoline alkaloids 4-methoxy-3-(3'-methyl-but-2'-enyl)-N-methyl-quinolin-2(1 H)-one, N-methylflindersine, dictamine, kokusaginine, G-fagarine, flindersiamine, as well as the fridelane-type triterpenes, frideline, fridelanol and its acetate derivative. Identification of these compounds was based on full analyses of spectroscopic data ({sup 1}H, {sup 13}C, {sup 1}D, {sup 2}D, IR, MS) and comparison with data reported in literature. Compound 4-methoxy-3-(3'-methyl-but-2'-enyl)-N-methyl-quinolin-2(1 H)-one is reported for the first time for the genus Esenbeckia. (author)

  4. Crystal structure of methyl (E)-4-[2-(8-hy-droxy-quinolin-2-yl)vin-yl]benzoate. (United States)

    Xu, Yu-Xing; Hu, Wei-Ji; Zhao, Guo-Liang


    The title compound, C19H15NO3, was synthesized by a Perkin reaction of 2-methyl-8-hy-droxy-quinoline and 4-formyl-2-methyl-benzoate in acetic anhydride under a nitro-gen atmosphere. The mol-ecule has an E conformation about the C=C bond, and the quinoline ring system and the benzene ring are inclined to one another by 29.22 (7)°. There is an intra-molecular O-H⋯N hydrogen bond in the 8-hy-droxy-quinoline moiety. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming inversion dimers with an R2(2)(28) ring motif. The dimers are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming sheets parallel to plane (10-1).

  5. Analysis of denitrifier community in a bioaugmented sequencing batch reactor for the treatment of coking wastewater containing pyridine and quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Yaohui; Xing, Rui; Wen, Donghui; Tang, Xiaoyan [Peking Univ., Beijing (CN). Key Lab. of Water and Sediment Sciences (Ministry of Education); Sun, Qinghua [Peking Univ., Beijing (CN). Key Lab. of Water and Sediment Sciences (Ministry of Education); Chinese Center for Disease Control and Prevention, Beijing (China). Inst. of Environmental Health and Related Product Safety


    The denitrifier community and associated nitrate and nitrite reduction in the bioaugmented and general sequencing batch reactors (SBRs) during the treatment of coking wastewater containing pyridine and quinoline were investigated. The efficiency and stability of nitrate and nitrite reduction in SBR was considerably improved after inoculation with four pyridine- or quinoline-degrading bacterial strains (including three denitrifying strains). Terminal restriction fragment length polymorphism (T-RFLP) based on the nosZ gene revealed that the structures of the denitrifier communities in bioaugmented and non-bioaugmented reactors were distinct and varied during the course of the experiment. Bioaugmentation protected indigenous denitrifiers from disruptions caused by pyridine and quinoline. Clone library analysis showed that one of the added denitrifiers comprised approximately 6% of the denitrifier population in the bioaugmented sludge. (orig.)

  6. Synthesis of novel benzimidazolyl-substituted acrylonitriles and amidino-substituted benzimidazo[1,2-a]quinolines. (United States)

    Hranjec, Marijana; Karminski-Zamola, Grace


    A series of novel benzimidazole derivatives 3-10 were synthesized. Benzimidazolyl-substituted acrylonitriles 3 and 4 underwent a photochemical dehydrocyclization reaction to give the corresponding mono- and dicyano-substituted benzimidazo[1,2-a] quinolines 5 and 6. Pinner reaction of these compounds did not give the expected mono- and diamidines, but rather only compounds 7-10, with amido groups at 6-position were isolated. A mechanism for the reaction is proposed. Acyclic compounds 3 and 4, as well as cyclic benzimidazo[1,2-a]quinolines 5-8, exhibit interesting spectroscopic properties and are potential biologically active compounds.

  7. Synthesis of Novel Benzimidazolyl-substituted Acrylonitriles and Amidino-substituted Benzimidazo[1,2-a]Quinolines

    Directory of Open Access Journals (Sweden)

    Grace Karminski-Zamola


    Full Text Available A series of novel benzimidazole derivatives 3-10 were synthesized. Benzimidazolyl-substituted acrylonitriles 3 and 4 underwent a photochemical dehydrocyclization reaction to give the corresponding mono- and dicyano-substituted benzimidazo[1,2-a] quinolines 5 and 6. Pinner reaction of these compounds did not give the expected mono- and diamidines, but rather only compounds 7-10, with amido groups at 6-position were isolated. A mechanism for the reaction is proposed. Acyclic compounds 3 and 4, as well as cyclic benzimidazo[1,2-a]quinolines 5-8, exhibit interesting spectroscopic properties and are potential biologically active compounds.

  8. Recent Advances in the C-H-Functionalization of the Distal Positions in Pyridines and Quinolines. (United States)

    Stephens, David E; Larionov, Oleg V


    This review summarizes recent developments in the C-H-functionalization of the distal positions of pyridines, quinolines and related azaheterocycles. While the functionalization of the C2 position has been known for a long time and is facilitated by the proximity to N1, regioselective reactions in the distal positions are more difficult to achieve and have only emerged in the last decade. Recent advances in the transition metal-catalyzed distal C-H-functionalization of these synthetically-important azaheterocycles are discussed in detail, with the focus on the scope, site-selectivity and mechanistic aspects of the reactions.

  9. Adsorption of naphthalene and quinoline on Pt, Pd and Rh: a DFT study. (United States)

    Santarossa, Gianluca; Iannuzzi, Marcella; Vargas, Angelo; Baiker, Alfons


    The adsorption of naphthalene and quinoline on Pt(111), Pd(111) and Rh(111) surfaces is studied using density functional theory. The metal surfaces are simulated by means of large confined clusters and for Pt by means of a slab with periodic boundary conditions (PBC). Calculation parameters such as basis set convergence, basis set superposition error and effects of cluster relaxation and size are analyzed in order to assess the aptness of the cluster model. For all the metals, the preferred sites of adsorption are analyzed, thus revealing their different behaviors concerning structure and stability of adsorption modes. On Pt, the molecules have the richest theoretical configurational variety. Naphthalene and quinoline are found to adsorb preferentially on di-bridge[7] sites on the three metals, and Rh exhibits higher adsorption energies than Pt and Pd. Structural features of the adsorbed molecules are correlated to the calculated adsorption energies. The di-bridge[7] adsorption modes are studied in deeper detail decomposing the adsorption energies in two terms arising from molecular distortion and binding interaction to the metal. Molecular distortion is correlated to the HOMO-LUMO energy gap. The larger adsorption energies found for interactions with Rh result from the lower contribution of the distortion term. Binding interactions are described by analyzing the wave functions of naphthalene and quinoline adsorbed on a subunit of the large clusters in order to reduce the complexity of the analysis. Molecular orbitals are studied using concepts of Frontier Molecular Orbitals theory. This approach reveals that in the adsorption of naphthalene and quinoline on Pt and Pd, an antibonding state lies below the Fermi energy, while on Rh all antibonding states are empty, in agreement with the larger interaction energies. In addition, further insight is gained by projecting the density of states on the d band of the clean surfaces and of the adsorbed systems. This results

  10. Ring-substituted 4-Hydroxy-1H-quinolin-2-ones: Preparation and Biological Activity

    Directory of Open Access Journals (Sweden)

    Jiri Dohnal


    Full Text Available In the study, a series of twelve ring-substituted 4-hydroxy-1H-quinolin-2-one derivatives were prepared. The procedures for synthesis of the compounds are presented. The compounds were analyzed using RP-HPLC to determine lipophilicity and tested for their photosynthesis-inhibiting activity using spinach (Spinacia oleracea L. chloroplasts. All the synthesized compounds were also evaluated for antifungal activity using in vitro screening with eight fungal strains. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed, as well as their structure-activity relationships (SAR.

  11. Quinoline derivatives bearing pyrazole moiety: Synthesis and biological evaluation as possible antibacterial and antifungal agents. (United States)

    El Shehry, Mohamed F; Ghorab, Mostafa M; Abbas, Samir Y; Fayed, Eman A; Shedid, Said A; Ammar, Yousry A


    In an attempt for development of new antimicrobial agents, three series of quinoline derivatives bearing pyrazole moiety have been synthesized. The first series was synthesized through the synthesis of 4-(quinolin-2-yloxy)benzaldehyde and 4-(quinolin-2-yloxy)acetophenone and then treatment with ketone or aldehyde derivatives to afford the corresponding chalcones. Cyclization of the latter chalcones with hydrazine derivatives led to the formation of new pyrazoline derivatives. The second series was synthesized via the synthesis of 2-hydrazinylquinoline and then treatment with formylpyrazoles to afford the corresponding hydrazonyl pyrazole derivatives. The third series was synthesized through the treatment of 2-hydrazinylquinoline with ethoxyethylidene, dithioacetal and arylidene derivatives to afford the corresponding pyrazole derivatives. The synthesized compounds were evaluated for their expected antibacterial and antifungal activities; where, the majority of these compounds showed potent antibacterial and antifungal activities against the tested strains of bacteria and fungi. Pyrazole derivative 13b showed better results when compared with the reference drugs as revealed from their MIC values (0.12-0.98 μg/mL). The pyrazole derivative 13b showed fourfold potency of gentamycin in inhibiting the growth of S. flexneri (MIC 0.12 μg/mL). Also, compound 13b showed fourfold potency of amphotericin B in inhibiting the growth of A. clavatus (MIC 0.49 μg/mL) and C. albicans (MIC 0.12 μg/mL), respectively. The same compound showed twofold potency of gentamycin in inhibiting the growth of P. vulgaris (MIC 0.98 μg/mL), equipotent to the ampicillin and amphotericin B in inhibiting the growth of S. epidermidis (MIC 0.49 μg/mL), A. fumigatus (MIC 0.98 μg/mL), respectively. Thus, these studies suggest that quinoline derivatives bearing pyrazole moiety are interesting scaffolds for the development of novel antibacterial and antifungal agents. Copyright © 2017





    In the past two decades, a wide variety of bioactive peptides have been discovered. Condensation of heterocyclic moieties viz nicotinic acid, thiazole coumarin, quinolin, furan, imidazole etc. with amino acids and peptides resulted in compounds with potent biological activities. Many of the heterocyclic found to exhibit antifungal, antibacterial, cytotoxic, antineoplastic, insectisidal, antiinflammatory, anthelmintic, tyrosinase inhibitory and melanin production inhibitory activities. Metroni...

  13. T3P- A Novel Catalyst for Aza-Diels-Alder Reaction: One-Pot Synthesis of Pyrano[3,2-c]quinolines and furano[3,2-c]quinolines

    Directory of Open Access Journals (Sweden)

    T. S. R. Prasanna


    Full Text Available T3P was found to be an efficient catalyst for the Aza-Diels–Alder reactions of aldimines with dihydropyran or dihydrofuran to afford the corresponding pyrano-and furo [3,2-c]quinolines in high yields with high diastereoselectivity in a short period of time.

  14. Application of Porous Nickel-Coated TiO2 for the Photocatalytic Degradation of Aqueous Quinoline in an Internal Airlift Loop Reactor

    Directory of Open Access Journals (Sweden)

    Mingxin Huo


    Full Text Available P25 film, prepared by a facile dip-coating method without any binder, was further developed in a recirculating reactor for quinoline removal from synthetic wastewater. Macroporous foam Ni, which has an open three-dimensional network structure, was utilized as a substrate to make good use of UV rays. Field emission scanning electron microscopy and X-ray diffraction analysis showed that the coated/calcinated P25 films consisted of two crystal phases, and had a number of uniform microcracks on the surface. The effects of initial quinoline concentration, light intensity, reaction temperature, aeration, and initial pH were studied. Increased reaction time, light intensity, environmental temperature, and gas aeration were found to significantly improve the quinoline removal efficiency. The aeration effect of oxygen dependency on the quinoline degradation had the trend pure oxygen > air > no gas > pure nitrogen with free O2. The solution pH crucially affected quinoline photodegradation; the high electrostatic adsorption of quinoline molecules on the TiO2 surface was strongly pH dependent. 2-Pyridine-carboxaldehyde, 3-pyridinecarboxaldehyde, and 2(1H-quinolinone were identified as the major intermediates of quinoline degradation. Based on these intermediates, a primary degradation mechanism was proposed. This reusable P25 film benefits the photodegradation of water contaminants and has potential in other various applications.

  15. Experimental and theoretical studies on IR, Raman, and UV-Vis spectra of quinoline-7-carboxaldehyde. (United States)

    Kumru, M; Küçük, V; Kocademir, M; Alfanda, H M; Altun, A; Sarı, L


    Spectroscopic properties of quinoline-7-carboxaldehyde (Q7C) have been studied in detail both experimentally and theoretically. The FT-IR (4000-50 cm(-1)), FT-Raman (4000-50 cm(-1)), dispersive-Raman (3500-50 cm(-1)), and UV-Vis (200-400 nm) spectra of Q7C were recorded at room temperature (25 °C). Geometry parameters, potential energy surface about CCH(O) bond, harmonic vibrational frequencies, IR and Raman intensities, UV-Vis spectrum, and thermodynamic characteristics (at 298.15K) of Q7C were computed at Hartree-Fock (HF) and density functional B3LYP levels employing the 6-311++G(d,p) basis set. Frontier molecular orbitals, molecular electrostatic potential, and Mulliken charge analyses of Q7C have also been performed. Q7C has two stable conformers that are energetically very close to each other with slight preference to the conformer that has oxygen atom of the aldehyde away from the nitrogen atom of the quinoline. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Deuterium isotope effects on 13C chemical shifts of 10-Hydroxybenzo[h]quinolines

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Kamounah, Fadhil S.; Gryko, Daniel T.


    Deuterium isotope effects on 13C-NMR chemical shifts are investigated in a series of 10-hydroxybenzo[h]quinolines (HBQ’s) The OH proton is deuteriated. The isotope effects on 13C chemical shifts in these hydrogen bonded systems are rather unusual. The formal four-bond effects are found to be nega...... with calculated OH stretching frequencies. Isotope effects on chemical shifts are calculated for systems with OH exchanged by OD. Hydrogen bond potentials are discussed. New and more soluble nitro derivatives are synthesized.......Deuterium isotope effects on 13C-NMR chemical shifts are investigated in a series of 10-hydroxybenzo[h]quinolines (HBQ’s) The OH proton is deuteriated. The isotope effects on 13C chemical shifts in these hydrogen bonded systems are rather unusual. The formal four-bond effects are found...... to be negative, indicating transmission via the hydrogen bond. In addition unusual long-range effects are seen. Structures, NMR chemical shifts and changes in nuclear shieldings upon deuteriation are calculated using DFT methods. Two-bond deuterium isotope effects on 13C chemical shifts are correlated...

  17. Dipodal quinoline-tethered fluorescent probe synthesis and investigation of spectroscopic properties (United States)

    Obalı, Aslıhan Yılmaz; Yilmaz, Menzeher Serkan; Uçan, Halil İsmet


    Novel quinoline-tethered fluorescent probe was designed and synthesized as multidentate ligand. Their sensing actions were confirmed by UV-Vis absorbance and emission spectroscopic studies in presence of perchlorate salts of Co2+, Li+, Fe2+, K+, Pb2+, Cu2+, Zn2+, Ni2+, Hg2+, Ag+ cations in acetonitrile (1 × 10-5 M for absorption studies, 1 × 10-7 M for fluorescence studies). It was found that the dipodal compounds can selectively bind to Cu2+ and Ag+ metal ions with a significant quenching in their emissions. The capture of Cu2+ and Ag+ by the probe resulted in deprotonation of the secondary amine conjugated to the quinoline-tethered probe, so that the electron-donation ability of the 'N' atom would be greatly enhanced and the probe (2) showed blue-shift in emission and exhibited an on-off fluorescent response. The binding study was explored by using fluorescence spectroscopy with Job plot method.

  18. Modification of oxidative status in Plasmodium berghei-infected erythrocytes by E-2-chloro-8-methyl-3-[(4'-methoxy-1'-indanoyl-2'-methyliden]-quinoline compared to chloroquine

    Directory of Open Access Journals (Sweden)

    Juan Rodrigues


    Full Text Available E-2-chloro-8-methyl-3-[(4'-methoxy-1'-indanoyl-2'-methyliden]-quinoline (IQ is a new quinoline derivative which has been reported as a haemoglobin degradation and ß-haematin formation inhibitor. The haemoglobin proteolysis induced by Plasmodium parasites represents a source of amino acids and haeme, leading to oxidative stress in infected cells. In this paper, we evaluated oxidative status in Plasmodium berghei-infected erythrocytes in the presence of IQ using chloroquine (CQ as a control. After haemolysis, superoxide dismutase (SOD, catalase, glutathione cycle and NADPH + H+-dependent dehydrogenase enzyme activities were investigated. Lipid peroxidation was also assayed to evaluate lipid damage. The results showed that the overall activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were significantly diminished by IQ (by 53.5% and 100%, respectively. Glutathione peroxidase activity was also lowered (31% in conjunction with a higher GSSG/GSH ratio. As a compensatory response, overall SOD activity increased and lipid peroxidation decreased, protecting the cells from the haemolysis caused by the infection. CQ shared most of the effects showed by IQ; however it was able to inhibit the activity of isocitrate dehydrogenase and glutathione-S-transferase. In conclusion, IQ could be a candidate for further studies in malaria research interfering with the oxidative status in Plasmodium berghei infection.

  19. Production of 9-thioxo-2,3,4,9-tetrahydro-pyrrolo[3,4-b]quinolin-1

    African Journals Online (AJOL)

    to hitherto undocumented pyrrolo[3,4-b]quinoline derivatives which latter may find use as synthones for more complicated ... Merely mixing together 9-thioxo derivative 3a and propyl- amine at room temperature reconstituted product A. ..... Witwatersrand for financial support. References and Notes. 1 D.C. Levendis, J. Moffit, ...

  20. Series of coordination polymers based on 4-(5-sulfo-quinolin-8-yloxy) phthalate and bipyridinyl coligands: Structure diversity and properties

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xun [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Liu, Jing [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001 (China); College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Li, Jin; Ma, Lu-Fang [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Wang, Li-Ya, E-mail: [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473601 (China); Ng, Seik-Weng [Department of Chemistry, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 80203 (Saudi Arabia); Qin, Guo-Zhan [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China)


    Reactions between later metal salts and conjugational N-hetrocyclic sulfonate/ carboxylic acid under the presence of bipyridyl auxiliary ligands afforded a series of manganese, nickel, zinc, silver, cadmium coordination polymers bearing with phenyl pendant arm attached to quinoline skeletons, and they have been characterized by elements analysis, thermogravimetry, infrared spectroscopy and single-crystal X-ray diffraction studying. The series of polymers show interesting structural diversity in coordination environment, dimensions and topologies. They are all built from 2-D networks constructed from metal cluster through sulfonate or carboxylate groups, as the secondary building unit (SBU). The thermalgravimetric analyses show that they display framework stabilities in solid state. Variable-temperature magnetic susceptibility studies reveal the existence of antiferromagnetic interactions between adjacent Mn (II) ions in 1, and ferromagnetic interactions between Ni(II) ions for 2, respectively. The photo-luminescence properties of 3-5 have also been investigated systemically. - Highlights: • A series of coordination polymers based on later transition metal ions have been obtained. • They contain conjugational N-hetrocyclic sulfonate-carboxylic acid and bipyridyl auxiliary ligands. • They have been characterized systemically. • They exhibit structure diversity and interesting properties.

  1. Efficient one-pot synthesis of new 1-amino substituted pyrrolo[1,2-a]quinoline-4-carboxylate esters via copper-free Sonogashira coupling reactions. (United States)

    Keivanloo, Ali; Kazemi, Shaghayegh Sadat; Nasr-Isfahani, Hossein; Bamoniri, Abdolhamid


    The reactions of several 2-chloroquinoline-3-carboxylate esters with propargyl alcohol and a secondary amine in the presence of palladium catalyst leads to the formation of new alkyl 1-amino substituted pyrrolo[1,2-a]quinoline-4-carboxylate derivatives. This one-pot process, carried out in the absence of any copper salt, provides an efficient method for the synthesis of functionalized pyrrolo[1,2-a]quinolines in good-to-high yields.

  2. Hydrogen-Bonding Interactions in Luminescent Quinoline-Triazoles with Dominant 1D Crystals

    Directory of Open Access Journals (Sweden)

    Shi-Qiang Bai


    Full Text Available Quinoline-triazoles 2-((4-(diethoxymethyl-1H-1,2,3-triazol-1-ylmethylquinoline (1, 2-((4-(m-tolyl-1H-1,2,3-triazol-1-ylmethylquinoline (2 and 2-((4-(p-tolyl-1H-1,2,3-triazol-1-ylmethylquinoline (3 have been prepared with CuAAC click reactions and used as a model series to probe the relationship between lattice H-bonding interaction and crystal direction of growth. Crystals of 1–3 are 1D tape and prism shapes that correlate with their intermolecular and solvent 1D lattice H-bonding interactions. All compounds were thermally stable up to about 200 C and blue-green emissive in solution.

  3. New pyrone and quinoline alkaloid from Almeidea rubra and their trypanocidal activity

    Energy Technology Data Exchange (ETDEWEB)

    Ambrozin, Alessandra R.P.; Mafezoli, Jair; Vieira, Paulo C.; Fernandes, Joao B.; Silva, M. Fatima das G.F. da [Sao Carlos Univ., SP (Brazil). Dept. de Quimica]. E-mail:; Ellena, Javier A. [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Fisica; Albuquerque, Sergio de [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Analises Clinicas, Toxicologicas, Bromatologicas


    The investigation of the ethyl acetate fraction of methanol extract from leaves of Almeidea rubra A. St.-Hil. (Rutaceae) afforded two new compounds 4-methoxy-6-[2-(methylamino)phenyl]-2Hpyran- 2-one and rel-(7R,8R)-8-[(E)-3-hydroxy-3-methyl-1-butenyl]-4,8-dimethoxy-5,6,7,8- tetrahydrofuro[2,3-b]quinoline-7-yl acetate, along with the known compounds arborinine, N-methyl- 1-hydroxy-3-methoxyacridone, skimmianine, kokusagine, isodutaduprine, isoskimmianine, and isokokusagine. Their structures were established based on their spectral data, and for the new compounds these data are described herein. Additionally, these compounds were assayed on the tripomastigote forms of Trypanosoma cruzi showing moderate trypanocidal activity. (author)

  4. Photophysical Model of 10-Hydroxybenzo[h]quinoline: Internal Conversion and Excited State Intramolecular Proton Transfer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Junghwa; Joo, Taiha [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of)


    Photophysics of 10-hydroxybenzo[h]quinoline (HBQ) has been in controversy, in particular, on the nature of the electronic states before and after the excited state intramolecular proton transfer (ESIPT), even though the dynamics and mechanism of the ESIPT have been well established. We report highly time resolved fluorescence spectra over the full emission frequency regions of the enol and keto isomers and the anisotropy in time domain to determine the accurate rates of the population decay, spectral relaxation and anisotropy decay of the keto isomer. We have shown that the ∼300 fs component observed frequently in ESIPT dynamics arises from the S{sub 2}→S{sub 1} internal conversion in the reaction product keto isomer and that the ESIPT occurs from the enol isomer in S{sub 1} state to the keto isomer in S{sub 2} state.

  5. Photocytotoxicity of a 5-nitrofuran-ethenyl-quinoline antiseptic (Quinifuryl to P388 mouse leukemia cells

    Directory of Open Access Journals (Sweden)

    Daghastanli N.A.


    Full Text Available Quinifuryl (MW 449.52, 2-(5'-nitro-2'-furanylethenyl-4-{N-[4'-(N,N-diethylamino-1'-methylbutyl]carbamoyl} quinoline, is a water soluble representative of a family of 5-nitrofuran-ethenyl-quinoline drugs which has been shown to be highly toxic to various lines of transformed cells in the dark. In the present study, the toxicity of Quinifuryl to P388 mouse leukemia cells was compared in the dark and under illumination with visible light (390-500 nm. Illumination of water solutions of Quinifuryl (at concentrations ranging from 0.09 to 9.0 µg/ml in the presence of P388 cells resulted in its photodecomposition and was accompanied by elevated cytotoxicity. A significant capacity to kill P388 cells was detected at a drug concentration as low as 0.09 µg/ml. The toxic effect detected at this drug concentration under illumination exceeded the effect observed in the dark by more than three times. Moreover, the general toxic effect of Quinifuryl, which included cell proliferation arrest, was nearly 100%. Both dose- and time-dependent toxic effects were measured under illumination. The LC50 value of Quinifuryl during incubation with P388 cells was ~0.45 µg/ml under illumination for 60 min and >12 µg/ml in the dark. We have demonstrated that the final products of the Quinifuryl photolysis are not toxic, which means that the short-lived intermediates of Quinifuryl photodecomposition are responsible for the phototoxicity of this compound. The data obtained in the present study are the first to indicate photocytotoxicity of a nitroheterocyclic compound and demonstrate the possibility of its application as a photosensitizer drug for photochemotherapy.

  6. Synthesis of 1H-pyrrolo[3,2-h]quinoline-8-amine derivatives that target CTG trinucleotide repeats. (United States)

    Matsumoto, Jun; Li, Jinxing; Dohno, Chikara; Nakatani, Kazuhiko


    We describe a new molecular design, synthesis, and investigation of small molecules that bind to CTG trinucleotide repeats in DNA. 1H-Pyrrolo[3,2-h]quinoline-8-amine (PQA) has a tricyclic aromatic system with unique non-linear hydrogen-bonding surface complementary to thymine. We have synthesized a series of PQA derivatives with different alkylamino linkers. These PQAs showed binding to pyrimidine bulge DNAs and CNG (N=T and C) repeats depending on the linker structure, while quinoline derivatives lacking the pyrrole ring showed much lower binding affinity. PQA is a useful molecular unit for both CTG and CCG repeat binding. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. 3,5-Diphenyl-1-(quinolin-2-yl-4,5-dihydro-1H-pyrazol-5-ol

    Directory of Open Access Journals (Sweden)

    Muhd. Hidayat bin Najib


    Full Text Available In the title compound, C24H19N3O, the pyrazole ring is close to being planar (r.m.s. deviation of the five fitted atoms = 0.062 Å, and each of the N-bound quinoline ring [dihedral angle = 9.90 (7°] and the C-bound phenyl ring in the 3-position is close to being coplanar [dihedral angle = 8.87 (9°]. However, the phenyl ring in the 5-position forms a dihedral angle of 72.31 (9°. The hydroxy group forms an intramolecular hydrogen bond to the quinoline N atom. In the crystal, molecules are connected into supramolecular layers two molecules thick in the bc plane by C—H...O and C—H...π interactions.

  8. In vitro phenotypic screening of 7-chloro-4-amino(oxy)quinoline derivatives as putative anti-Trypanosoma cruzi agents. (United States)

    Fonseca-Berzal, Cristina; Rojas Ruiz, Fernando A; Escario, José A; Kouznetsov, Vladimir V; Gómez-Barrio, Alicia


    In this study, a series of 22 pre-synthesized 7-chloro-4-amino(oxy)quinoline derivatives was assayed in vitro as potential antichagasic agents. A primary screening against Trypanosoma cruzi epimastigotes and a non-specific cytotoxicity assay on murine fibroblasts were simultaneously performed, resulting quinolines 3, 7 and 12 with great selectivity (SI) on the extracellular parasite (SI7, SI3, SI12 and SIBZ >9.44). Therefore, the activity of these derivatives was evaluated on intracellular amastigotes, achieving derivative 7 the best SI (SI=12.73). These results, supported by the in silico prediction of a good oral bioavailability and a suitable risk profile, propose the 4-amino-7-chloroquinoline scaffold as a potential template for designing trypanocidal prototypes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. 3,5-Diphenyl-1-(quinolin-2-yl)-4,5-dihydro-1H-pyrazol-5-ol. (United States)

    Najib, Muhd Hidayat Bin; Tan, Ai Ling; Young, David J; Ng, Seik Weng; Tiekink, Edward R T


    In the title compound, C(24)H(19)N(3)O, the pyrazole ring is close to being planar (r.m.s. deviation of the five fitted atoms = 0.062 Å), and each of the N-bound quinoline ring [dihedral angle = 9.90 (7)°] and the C-bound phenyl ring in the 3-position is close to being coplanar [dihedral angle = 8.87 (9)°]. However, the phenyl ring in the 5-position forms a dihedral angle of 72.31 (9)°. The hy-droxy group forms an intra-molecular hydrogen bond to the quinoline N atom. In the crystal, mol-ecules are connected into supra-molecular layers two mol-ecules thick in the bc plane by C-H⋯O and C-H⋯π inter-actions.

  10. 7-(3-Chlorophenylamino-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic Acid

    Directory of Open Access Journals (Sweden)

    Ghassan F. Shattat


    Full Text Available 7-(3-Chlorophenylamino-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid (2 was prepared and fully characterized by NMR, IR, and MS. Compound 2 exhibited good antibacterial activity against gram-positive standard and resistant strains.

  11. A New Quinoline-Based Acylhydrazone for Highly Selective Fluorescence Recognition of Cu(II) and Sulfide in Aqueous Solution

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lijun; Zhou, Pei; Huang, Zhenlong; Zhao, Jia; Cai, Mingjun [Bohai Univ., Jinzhou (China); Qi, Zhikai [Shanxi Normal Univ., Linfen (China)


    A new quinoline-based acylhydrazone (1) has been synthesized and applied as a fluorescent probe. Probe 1 exhibits high selectivity and sensitivity to Cu{sup 2+} with fluorescence 'ON-OFF' behavior in HEPES buffered (1% DMSO, HEPES 20 mM, pH = 7.4) solution. The on-site generated 1-Cu{sup 2+} complex displays excellent selectivity to sulfide ions with fluorescence 'OFF-ON' performance through copper displacement approach.

  12. Synthesis of Novel Benzimidazolyl-substituted Acrylonitriles and Amidino-substituted Benzimidazo[1,2-a]Quinolines


    Grace Karminski-Zamola; Marijana Hranjec


    A series of novel benzimidazole derivatives 3-10 were synthesized. Benzimidazolyl-substituted acrylonitriles 3 and 4 underwent a photochemical dehydrocyclization reaction to give the corresponding mono- and dicyano-substituted benzimidazo[1,2-a] quinolines 5 and 6. Pinner reaction of these compounds did not give the expected mono- and diamidines, but rather only compounds 7-10, with amido groups at 6-position were isolated. A mechanism for the reaction is proposed. Acyclic compounds 3 and 4, ...

  13. A photoluminescent interpenetrating metal-organic frame work based on Cu4I4 and novel azino-quinoline ligand (United States)

    Pal, Pankaj K.; Mukherjee, Anindita; Ghosh, Anindya; Patra, Goutam K.


    Synthesis of a novel, triply-interpenetrating metal-organic framework 1.H2O is described here. The coordination polymer was synthesized by simple reaction of Cu2I2 with an azino-quinoline ligand (L1). The X-ray crystal structure analysis reveals that the complex 1.H2O is a 2-D coordination polymer having (4,4‧) grid network architecture. The ligand L1 possesses quinoline group and the 2-D structure of 1.H2O contains distorted cubane type Cu4I4 SBU unit. Each of the four Cu(I) ions posses tetrahedral coordination environment. Metal-organic framework in 1.H2O shows strong photoluminescence property at room temperature in solid state and emission spectra shows a blue shift of the peak in comparison to the free azino-quinoline ligand (L1). The coordination polymer 1.H2O was found to be stable up to 290 °C.

  14. Detection of Quinoline in G. boninense-Infected Plants Using Functionalized Multi-Walled Carbon Nanotubes: A Field Study

    Directory of Open Access Journals (Sweden)

    Fowotade Sulayman Akanbi


    Full Text Available Carbon nanotubes (CNTs reinforced with gold nanoparticles (AuNPs and chitosan nanoparticles (CTSNPs were anchored on a screen-printed electrode to fabricate a multi-walled structure for the detection of quinoline. The surface morphology of the nanocomposites and the modified electrode was examined by an ultra-high resolution field emission scanning electron microscope (FESEM, and Fourier-transform infrared (FT-IR spectroscopy was used to confirm the presence of specific functional groups on the multi-walled carbon nanotubes MWCNTs. Cyclic voltammetry (CV and linear sweep voltammetry (LSV were used to monitor the layer-by-layer assembly of ultra-thin films of nanocomposites on the surface of the electrode and other electrochemical characterizations. Under optimized conditions, the novel sensor displayed outstanding electrochemical reactivity towards the electro-oxidation of quinoline. The linear range was fixed between 0.0004 and 1.0 μM, with a limit of detection (LOD of 3.75 nM. The fabricated electrode exhibited high stability with excellent sensitivity and selectivity, specifically attributable to the salient characteristics of AuNPs, CTSNPs, and MWCNTs and the synergistic inter-relationship between them. The newly developed electrode was tested in the field. The Ipa increased with an increase in the amount of quinoline solution added, and the peak potential deviated minimally, depicting the real capability of the newly fabricated electrode.

  15. New rare-earth quinolinate complexes for organic light-emitting devices

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, H. [Physics Department, Pontifical Catholic University of Rio de Janeiro, 22453-900 Rio de Janeiro (Brazil); Paolini, T.B. [Chemistry Institute, Department of Fundamental Chemistry, University of São Paulo, USP, 05599-970 São Paulo (Brazil); Niyama, E. [Physics Department, Pontifical Catholic University of Rio de Janeiro, 22453-900 Rio de Janeiro (Brazil); Brito, H.F. [Chemistry Institute, Department of Fundamental Chemistry, University of São Paulo, USP, 05599-970 São Paulo (Brazil); Cremona, M., E-mail: [Physics Department, Pontifical Catholic University of Rio de Janeiro, 22453-900 Rio de Janeiro (Brazil)


    Because of its thermal and morphological stability and optical and electrical properties, tris(8-hydroxyquinoline) aluminum (Alq{sub 3}) is one of the most widely used electron transporting materials in organic light-emitting devices (OLEDs). The search for substitutes for this compound constitutes an important field of research in organic electronics. We report on a study of a new rare-earth tetrakis 8-hydroxyquinoline complex. Synthesis of tris complexes with rare-earth metals and 8-hydroxyquinoline resulted in unstable compounds. However, the inclusion of an additional quinoline group stabilized these compounds. Li[RE(q){sub 4}] (where RE = La{sup 3+}, Lu{sup 3+} and Y{sup 3+} and q = 8-hydroxyquinoline) were synthesized and then used as the electron-transporting and emitting layer in OLEDs. Thin films were deposited in a high-vacuum environment by thermal evaporation on quartz and silicon substrates. Optical characterization of the RE complexes revealed emission in the 510–525 nm range, the same as that observed for Alq{sub 3}, while absorption was observed at wavelengths of 382 nm for the Y/La complexes and 388 nm for the Lu complex. The OLEDs were fabricated with an indium tin oxide layer (ITO) as the anode, (N,N′-bis (1-naphtyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine) NPB as the hole-transporting layer (25 nm), Li[RE(q){sub 4}] as the electron-transporting and emitting layer (40 nm) and aluminum as the cathode (120 nm). The electroluminescence (EL) spectra showed a broad band from 520 to 540 nm and green-colored emission associated with the 8-hydroxyquinoline ligand. There was an interesting dependence of the maximum energy peak position and half-width of the emission band in the EL spectra on the atomic radius of the RE ion used. The best luminance for the OLEDs produced in this study was achieved with the Li[RE(q){sub 4}] compound. The optical and electrical properties of this OLED were comparable to those of similar devices based on Alq{sub 3

  16. Green synthesis of novel quinoline based imidazole derivatives and evaluation of their antimicrobial activity

    Directory of Open Access Journals (Sweden)

    N.C. Desai


    Full Text Available We have described the conventional and microwave method for the synthesis of N-(4-((2-chloroquinolin-3-ylmethylene-5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-1-yl(arylamides 3a–l. It is observed that the solvent-free microwave thermolysis is a convenient, rapid, high-yielding, and environmental friendly protocol for the synthesis of quinoline based imidazole derivatives when compared with conventional reaction in a solution phase. Antimicrobial activity of the newly synthesized compounds is screened in vitro on the following microbial cultures: Escherichia coli (MTCC 443, Pseudomonas aeruginosa (MTCC 1688, Staphylococcus aureus (MTCC 96, Streptococcus pyogenes (MTCC 442, Candida albicans (MTCC 227, Aspergillus niger (MTCC 282, Aspergillus clavatus (MTCC 1323. All the synthesized bio-active molecules are tested for their in vitro antimicrobial activity by bioassay namely serial broth dilution. Among these compounds 3c, 3d, 3f, 3h and 3j show significant potency against different microbial strains. All the compounds have been characterized by IR, 1H NMR, 13C NMR and mass spectral data. On the basis of statistical analysis, it is observed that these compounds give significant co-relation.

  17. Investigating the Spectrum of Biological Activity of Substituted Quinoline-2-Carboxamides and Their Isosteres

    Directory of Open Access Journals (Sweden)

    Ales Imramovsky


    Full Text Available In this study, a series of thirty-five substituted quinoline-2-carboxamides and thirty-three substituted naphthalene-2-carboxamides were prepared and characterized. They were tested for their activity related to the inhibition of photosynthetic electron transport (PET in spinach (Spinacia oleracea L. chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four mycobacterial species. N-Cycloheptylquinoline-2-carboxamide, N-cyclohexylquinoline-2-carboxamide and N-(2-phenylethylquinoline-2-carboxamide showed higher activity against M. tuberculosis than the standards isoniazid or pyrazinamide and 2-(pyrrolidin-1-ylcarbonylquinoline and 1-(2-naphthoylpyrrolidine expressed higher activity against M. kansasii and M. avium paratuberculosis than the standards isoniazid or pyrazinamide. The most effective antimycobacterial compounds demonstrated insignificant toxicity against the human monocytic leukemia THP-1 cell line. The PET-inhibiting activity expressed by IC50 value of the most active compound N-benzyl-2-naphthamide was 7.5 μmol/L. For all compounds, the structure-activity relationships are discussed.

  18. A Cr(VI) selective probe based on a quinoline-amide calix[4]arene (United States)

    Ferreira, Juliane F.; Bagatin, Izilda A.


    A new quinoline-amide calix[4]arene 3-receptor for detection of hazardous anions and cations have been synthesized. The 3-receptor was examined for its sensing properties towards several different anions (Cr2O72 -, SCN-, F-, Cl-, NO3-) and metal ions (Hg2+, Cd2+, Ag+) by UV-vis and fluorescence spectroscopies. It was detected that the 3-receptor has only sensing ability for Cr2O72 - and Hg2+ ions, resulting in the association constants higher for Cr2O72 - than to the Hg2+ ions. High selectivity towards Cr2O72 - were also observed by fluorescence measurement among other ions (F-, Cl-, SCN-, Hg2+, Cd2+, Ag+) with a low limit of detection (7.36 × 10-6 mol dm-3). Proton NMR anion-binding investigations revealed a strong interaction of Cr2O72 - anion with NH and CH groups of the receptor, showing that the combination with hydrogen-bonds donor groups strengthened the anion receptor association. Furthermore, remarkable association constants for dichromate anion obtained by all techniques strongly suggest the 3-receptor as a selective Cr(VI) sensor.

  19. 3-Hydroxykynurenine and quinolinate: pathogenic synergism in early grade Huntington's disease? (United States)

    Guidetti, Paolo; Schwarcz, Robert


    Huntington's Disease (HD), an inherited neurodegenerative disorder, is caused by an abnormal polyglutamine extension of a protein named huntingtin. This genetic defect is believed to result in heightened neuronal susceptibility to excitotoxic injury, a likely mechanism of neurodegeneration in HD. Two neuroactive kynurenine pathway metabolites, quinolinate (QUIN) and kynurenate (KYNA), have been proposed to play critical roles in the precipitation and prevention, respectively, of excitotoxic neuron death in HD. We now provide evidence that a third kynurenine pathway metabolite, 3-hydroxykynurenine (3-HK), should also be considered a pathogen in HD. The brain levels of this free radical generator are increased 5-10-fold in early stage (Grade 1) HD patients. In the same brains, QUIN levels are also significantly elevated in the cortex and in the neostriatum, but not in the cerebellum. In contrast, brain 3-HK and QUIN levels are either unchanged or reduced in Grade 2 and end stage (Grade 3-4) HD patients. Brain KYNA levels are moderately increased during the early disease stages and decrease as the illness progresses. In rats, 3-HK potentiates striatal QUIN toxicity, and this pro-excitotoxic effect can be prevented by free radical scavengers. Taken together, these studies provide further evidence for an involvement of kynurenine pathway metabolites in the early phases of HD neuropathology and suggest novel therapeutic strategies for the disease.

  20. 3-(2,3,5,6,7,8-Hexahydro-1H-cyclopenta[b]quinolin-9-yl-1,5-bis(4-methoxyphenylbiuret

    Directory of Open Access Journals (Sweden)

    Koichiro Nishibe


    Full Text Available Ipidacrine (2,3,5,6,7,8-hexahydro-1H-cyclopenta[b]quinolin-9-amine was reacted with 4-methoxyphenyl isocyanate to give the title compound, C28H30N4O4. An intramolecular N—H...O hydrogen bond results in an essentially planar [r.m.s. deviation from the mean plane is 0.126 (1 Å] conformation for the biuret unit. The central ring of the quinoline unit is twisted by 78.2 (1° with respect to the biuret mean plane, whereas the two 4-methoxybenzene rings are twisted out of this plane by 24.3 (1° and 48.5 (1°, resulting in an overall propeller-like structure. An intermolecular N—H...N hydrogen bond between the biuret NH atom and the quinoline ring nitrogen defines the crystal packing.

  1. Synthesis of 2-Substituted Furo[2,3-b]- and Furo[3,2-c]quinolines via Heterogeneous Palladium-catalyzed Heteroannulation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hee Jung [Korea Basic Science Institute, Seoul (Korea, Republic of); Yang, Ok-Kyung; Park, Young Chul; Yum, Eul Kgun [Chungnam National University, Daejon (Korea, Republic of)


    As a part of our continuing organometallic studies on diversification of nitrogen-containing biologically active heterocycles, we attempted to synthesize furo[2,3-b]- and furo[3,2-c]quinolines starting from o-halohydroxyquinolines and terminal alkynes with heterogeneous Pd(OAc)2 catalyst, which was supported by nanosized pore carbon ball. 2-substituted furo[2,3-b]quinolines and furo[3,2-c]quinolines were synthesized from the reaction of 3-iodoquinolin-2-ol and 3-iodoquinolin-4-ol, respectively, with diverse alkynes. The heteroannulation reaction proceeds with Sonogashira coupling followed by 5-endo-dig cyclization in good isolated yields under copper and ligand free conditions.

  2. Synthesis, characterization, crystal structure, in-vitro anti-inflammatory and molecular docking studies of 5-mercapto-1-substituted tetrazole incorporated quinoline derivative (United States)

    Sureshkumar, K.; Maheshwaran, V.; Dharma Rao, T.; Themmila, Khamrang; Ponnuswamy, M. N.; Kadhirvel, Saraboji; Dhandayutham, Saravanan


    A novel 5-mercapto-1-substituted tetrazole incorporated quinoline analog was synthesized. The compound 2-Cyclopropyl-4-(4-fluorophenyl)-3-{1-[2-(4-methoxybenzyloxy)ethyl]1H-tetrazol-5-ylsulfanylmethyl}quinoline was characterized by IR, Mass, 1H and 13C NMR spectroscopic techniques. Molecular structure was confirmed by using single crystal X-ray diffraction technique. Thermal behavior was studied by using TGA and DSC techniques. Further, in vitro anti-inflammatory and in silico docking analysis has been carried out to study the activity of the compound.

  3. Acetylcholinesterase and Butyrylcholinesterase Inhibitory Activities of β-Carboline and Quinoline Alkaloids Derivatives from the Plants of Genus Peganum

    Directory of Open Access Journals (Sweden)

    Ting Zhao


    Full Text Available It was reported that the main chemical constituents in plants of genus Peganum were a serial of β-carboline and quinoline alkaloids. These alkaloids were quantitatively assessed for selective inhibitory activities on acetylcholinesterase (AChE and butyrylcholinesterase (BChE by in vitro Ellman method. The results indicated that harmane was the most potent selective AChE inhibitor with an IC50 of 7.11 ± 2.00 μM and AChE selectivity index (SI, IC50 of BChE/IC50 of AChE of 10.82. Vasicine was the most potent BChE inhibitor with feature of dual AChE/BChE inhibitory activity, with an IC50 versus AChE/BChE of 13.68 ± 1.25/2.60 ± 1.47 μM and AChE SI of 0.19. By analyzing and comparing the IC50 and SI of those chemicals, it was indicated that the β-carboline alkaloids displayed more potent AChE inhibition but less BChE inhibition than quinoline alkaloids. The substituent at the C7 position of the β-carboline alkaloids and C3 and C9 positions of quinoline alkaloids played a critical role in AChE or BChE inhibition. The potent inhibition suggested that those alkaloids may be used as candidates for treatment of Alzheimer’s disease. The analysis of the quantitative structure-activity relationship of those compounds investigated might provide guidance for the design and synthesis of AChE and BChE inhibitors.

  4. Central nervous system exposure of next generation quinoline methanols is reduced relative to mefloquine after intravenous dosing in mice

    Directory of Open Access Journals (Sweden)

    Shackleford David M


    Full Text Available Abstract Background The clinical use of mefloquine (MQ has declined due to dose-related neurological events. Next generation quinoline methanols (NGQMs that do not accumulate in the central nervous system (CNS to the same extent may have utility. In this study, CNS levels of NGQMs relative to MQ were measured and an early lead chemotype was identified for further optimization. Experimental design The plasma and brain levels of MQ and twenty five, 4-position modified NGQMs were determined using LCMS/MS at 5 min, 1, 6 and 24 h after IV administration (5 mg/kg to male FVB mice. Fraction unbound in brain tissue homogenate was assessed in vitro using equilibrium dialysis and this was then used to calculate brain-unbound concentration from the measured brain total concentration. A five-fold reduction CNS levels relative to mefloquine was considered acceptable. Additional pharmacological properties such as permeability and potency were determined. Results The maximum brain (whole/free concentrations of MQ were 1807/4.9 ng/g. Maximum whole brain concentrations of NGQMs were 23 - 21546 ng/g. Maximum free brain concentrations were 0.5 to 267 ng/g. Seven (28% and two (8% compounds exhibited acceptable whole and free brain concentrations, respectively. Optimization of maximum free brain levels, IC90s (as a measure or potency and residual plasma concentrations at 24 h (as a surrogate for half-life in the same molecule may be feasible since they were not correlated. Diamine quinoline methanols were the most promising lead compounds. Conclusion Reduction of CNS levels of NGQMs relative to mefloquine may be feasible. Optimization of this property together with potency and long half-life may be feasible amongst diamine quinoline methanols.

  5. Chlorido(8-hydroxyquinoline-κ2N,O(quinolin-8-olato-κ2N,Ozinc methanol monosolvate

    Directory of Open Access Journals (Sweden)

    Ezzatollah Najafi


    Full Text Available In the title compound, [Zn(C9H6NOCl(C9H7NO]·CH3OH, the ZnII ion is N,O-chelated by both a neutral and a deprotonated quinolin-8-ol ligand, with a chloride ligand in the apical site completing the square-pyramidal coordination geometry. The ZnII ion is displaced by 0.586 Å in the direction of the chloride ligand from the atoms forming the square plane. In the crystal, the components are linked by intermolecular O—H...O hydrogen bonds, generating chains along the b axis.

  6. Application of N-Quinoline-2-carboxamido-8-aminoquinoline in Fabrication of a Ho(III)-PVC Membrane Sensor


    Hassan Ali Zamani; Samaneh Langroodi; Soraia Meghdadi


    The N-quinoline-2-carboxamido-8-aminoquinoline (QCA) was used as a suitable ion carrier in the construction of a Ho(III) PVC-based membrane sensor. This sensor demonstrated good selectivity and sensitivity towards the holmium ion for a broad variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The proposed electrode exhibits a linear dynamic range between 1.0×10-6 and 1.0×10-2 M, with a near Nernstian slope of 20.4±0.3 mV per decade and a detection limit of 4...

  7. Dichlorido[methyl 2-(quinolin-8-yloxy-κ2N,Oacetate-κO]mercury(II

    Directory of Open Access Journals (Sweden)

    Yu-Hong Wang


    Full Text Available In the neutral title complex, [HgCl2(C12H11NO3], the HgII ion is pentacoordinated by two Cl atoms, one N atom and two weakly coordinating O atoms from the methyl 2-(quinolin-8-yloxyacetate ligand. The coordination around the HgII ion may be described as highly distorted trigonal–bipyramidal. Centrosymmetric dimers are formed by an additional weak Hg...Cl interaction, leading to a distorted octahedral coordination geometry around the HgII ion.

  8. Rh-Catalyzed, Regioselective, C-H Bond Functionalization: Access to Quinoline-Branched Amines and Dimers. (United States)

    Reddy, M Damoder; Fronczek, Frank R; Watkins, E Blake


    Rh-catalyzed, chelation-induced, C-5 regioselective C-H functionalization of 8-amidoquinolines with a range of N-Boc aminals is reported for the first time. The addition of in situ generated imines to C(sp2)-H bonds afforded branched amines in good to excellent yields. Moreover, this transformation features good functional group compatibility, broad substrate scope, and mild reaction conditions and is suitable for gram-scale synthesis. In addition, an unprecedented, chelation-induced, site-selective, remote dimerization of quinolines led to the formation of dimer frameworks in moderate yields under Rh-catalyzed conditions.

  9. Interference with hemozoin formation represents an important mechanism of schistosomicidal action of antimalarial quinoline methanols.

    Directory of Open Access Journals (Sweden)

    Juliana B R Corrêa Soares

    Full Text Available BACKGROUND: The parasitic trematode Schistosoma mansoni is one of the major causative agents of human schistosomiasis, which afflicts 200 million people worldwide. Praziquantel remains the main drug used for schistosomiasis treatment, and reliance on the single therapy has been prompting the search for new therapeutic compounds against this disease. Our group has demonstrated that heme crystallization into hemozoin (Hz within the S. mansoni gut is a major heme detoxification route with lipid droplets involved in this process and acting as a potential chemotherapeutical target. In the present work, we investigated the effects of three antimalarial compounds, quinine (QN, quinidine (QND and quinacrine (QCR in a murine schistosomiasis model by using a combination of biochemical, cell biology and molecular biology approaches. METHODOLOGY/PRINCIPAL FINDINGS: Treatment of S. mansoni-infected female Swiss mice with daily intraperitoneal injections of QN, and QND (75 mg/kg/day from the 11(th to 17(th day after infection caused significant decreases in worm burden (39%-61% and egg production (42%-98%. Hz formation was significantly inhibited (40%-65% in female worms recovered from QN- and QND-treated mice and correlated with reduction in the female worm burden. We also observed that QN treatment promoted remarkable ultrastructural changes in male and female worms, particularly in the gut epithelium and reduced the granulomatous reaction to parasite eggs trapped in the liver. Microarray gene expression analysis indicated that QN treatment increased the expression of transcripts related to musculature, protein synthesis and repair mechanisms. CONCLUSIONS: The overall significant reduction in several disease burden parameters by the antimalarial quinoline methanols indicates that interference with Hz formation in S. mansoni represents an important mechanism of schistosomicidal action of these compounds and points out the heme crystallization process as a

  10. Antibacterial activity of N-methylbenzofuro[3,2-b]quinoline and N-methylbenzoindolo[3,2-b]-quinoline derivatives and study of their mode of action. (United States)

    Sun, Ning; Du, Ruo-Lan; Zheng, Yuan-Yuan; Huang, Bao-Hua; Guo, Qi; Zhang, Rui-Fang; Wong, Kwok-Yin; Lu, Yu-Jing


    The emergence of multidrug-resistant bacteria causes an urgent need for new generation of antibiotics, which may have a different mechanism of inhibition or killing action from the existing. Targeting at the inhibition of bacterial cell division via the control of FtsZ function is one of the effective and promising approaches. Some natural extracts from plants such as sanguinarine and berberine (analogs of pyridinium compounds) are known to alter FtsZ function. In this study, a series of novel quaternary pyridinium compounds was constructed based on the N-methylbenzofuro[3,2-b]quinoline and N-methylbenzoindolo[3,2-b]-quinoline derivatives and their antibacterial activity against nine significant pathogens was investigated using broth microdilution method. In the in vitro assay, the compounds showed strong antibacterial activities against various testing strains, which include some drug-resistant strains such as methicillin-resistant S. aureus and vancomycin-resistant E. faecium. Our results of morphology change of B. subtilis cells and molecular docking proved that the compounds functioned as an effective inhibitor to suppress FtsZ polymerization and FtsZ GTPase activity and thus the compound stops cell division and cause cell death through interacting with C-terminal interdomain cleft of FtsZ. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  11. Determination of mercury(II) in aquatic plants using quinoline-thiourea conjugates as a fluorescent probe. (United States)

    Feng, Guodong; Ding, Yuanyuan; Gong, Zhiyong; Dai, Yanna; Fei, Qiang


    In this study, a quinoline-thiourea conjugate (1-phenyl-3-(quinoline-8-yl) thiourea, PQT) was synthesized and used as a fluorescence sensor to detect mercury ion. The observation is coincident with the well-documented phenomenon that a thiocarbonyl-containing group on a fluorochrome quenches the fluorescence due to the heavy atom effect of the S atom. The large fluorescence enhancement of PQT in the buffered MeCN-water mixture (1/1 v/v; HEPES 100 mM; pH 8.0) was caused by the Hg(2+) induced transformation of the thiourea function into a urea group. As such, protic solvents can be ascribed to hydrogen bond formation on the carbonyl oxygen to reduce the internal conversion rate. The fluorescence intensity of PQT was enhanced quantitatively with an increase in the concentration of mercury ion. The limit of detection of Hg(2+) was 7.5 nM. The coexistence of other metal ions with mercury had no obvious influence on the detection of mercury. A quinolone-thiourea conjugate was used as a fluorescent probe to detect Hg(2+) in aquatic plants and the experimental results were satisfactory.

  12. Tetra­kis(quinolin-8-olato-κ2 N,O)hafnium(IV) toluene disolvate (United States)

    Viljoen, J. Augustinus; Visser, Hendrik G.; Roodt, Andreas; Steyn, Maryke


    In the title compound, [Hf(C9H6NO)4]·2C7H8, the hafnium metal centre is coordinated by four N,O-donating bidentate quinolin-8-olate ligands arranged to give a square-anti­prismatic coordination polyhedron with a slightly distorted dodeca­hedral geometry. The average Hf—O and Hf—N distances are 2.096 (3) and 2.398 (3) Å, respectively, and the average O—Hf—N bite angle is 70.99 (11)°. The crystal packing is controlled by π–π inter­actions between quinoline ligands of neighbouring mol­ecules and hydrogen-bonding inter­actions. The inter­planar distances vary between 3.138 (1) and 3.208 (2) Å, while the centroid–centroid distances range from 3.576 (1) to 4.074 (1) Å. PMID:21578562

  13. Comparable structural and optical properties of 4H-pyrano [3, 2-c] quinoline derivatives thin films (United States)

    Zeyada, H. M.; El-Nahass, M. M.; El-Shabaan, M. M.


    The structural and optical properties of 2-Amino-6-ethyl-5-oxo-4-(3-phenoxyphenyl) - 5, 6- dihydro - 4H-pyrano [3,2-c] quinoline-3- carbonitrile (Ph-HPQ) and 2-Amino-4-(2-chlorophenyl)-6-ethyl-5-oxo-5,6-dihydro-4H-pyrano [3,2-c] quinoline-3-carbonitrile (Ch-HPQ) thin films are studied. The compounds are polycrystalline in as- synthesised powder form; they became nanocrystallites dispersed in amorphous matrix upon thermal deposition to form thin films. FTIR spectral measurements showed no change in chemical bonds of the compounds after being deposited to form thin films. The optical properties have been determined based on spectrophotometer measurements of transmittance and reflectance at nearly normal incidence of light in the spectral range of 200-2500 nm. The absorption parameters, molar extinction coefficient, oscillator strength and electric dipole strength, are reported. The type of electron transition is determined from analysis of absorption coefficient spectra near the onset and optical absorption edges. The onset and optical energy gaps for Ph-HPQ and Ch-HPQ thin films are determined. The single oscillator model is applied to calculate the dispersion parameters of the investigated thin films. In addition, oscillator and dispersion energies, the high-frequency dielectric constant, lattice dielectric constant and ratio of free charge carriers concentrations to their effective masses are evaluated for the compounds under investigation.

  14. 3-(2,3,5,6,7,8-Hexahydro-1H-cyclo-penta-[b]quinolin-9-yl)-1,5-bis-(4-methoxy-phen-yl)biuret

    National Research Council Canada - National Science Library

    Sakurai, Kaori; Noguchi, Keiichi; Nishibe, Koichiro


    ...] conformation for the biuret unit. The central ring of the quinoline unit is twisted by 78.2 (1)° with respect to the biuret mean plane, whereas the two 4-methoxy-benzene rings are twisted out of this...

  15. Discovery of Quinoline-Derived Trifluoromethyl Alcohols, Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model. (United States)

    Sittaramane, Vinoth; Padgett, Jihan; Salter, Philip; Williams, Ashley; Luke, Shauntelle; McCall, Rebecca; Arambula, Jonathan F; Graves, Vincent B; Blocker, Mark; Van Leuven, David; Bowe, Keturah; Heimberger, Julia; Cade, Hannah C; Immaneni, Supriya; Shaikh, Abid


    In this study the rational design, synthesis, and anticancer activity of quinoline-derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp(3) -C-H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4-trifluoro-3-hydroxy-3-(quinolin-2-ylmethyl)butanoate (1), 2-benzyl-1,1,1-trifluoro-3-(quinolin-2-yl)propan-2-ol (2), and trifluoro-3-(isoquinolin-1-yl)-2-(thiophen-2-yl)propan-2-ol (3). Compounds 2 and 3 were found to be more toxic than compound 1; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2, with an LC50 value of 14.14 μm, has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Synthesis and structure-activity studies on acidic amino acids and related diacids as NMDA receptor ligands

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B


    The 3-isoxazolol amino acids (S)-2-amino-3-(3-hydroxy-5-methyl-4- isoxazolyl)propionic acid [(S)-AMPA, 2] and (R,S)-2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid (AMAA, 5a) (Figure 1) are potent and specific agonists at the AMPA and N-methyl-D-aspartic acid (NMDA) subtypes, respectively......, of (S)-glutamic acid (1) receptors. A number of amino acids and diacids structurally related to AMAA were synthesized and tested electrophysiologically and in receptor-binding assays. The hydroxymethyl analogue 7c of AMAA was an NMDA agonist approximately equipotent with AMAA in the [3H...... by molecular mechanics calculations. Compound 7a possesses extra steric bulk and shows significant restriction of conformational flexibility compared to AMAA and 7c, which may be determining factors for the observed differences in biological activity. Although the nitrogen atom of quinolinic acid (6) has very...

  17. Trivalent Zirconium and Hafnium Metal-Organic Frameworks for Catalytic 1,4-Dearomative Additions of Pyridines and Quinolines. (United States)

    Ji, Pengfei; Feng, Xuanyu; Veroneau, Samuel S; Song, Yang; Lin, Wenbin


    We report the quantitative conversion of [M(IV)6(μ3-O)4(μ3-OH)4Cl12](6-) nodes in the MCl2-BTC metal-organic framework into the [M(III)6(μ3-O)4(μ3-ONa)4H6](6-) nodes in M(III)H-BTC (M = Zr, Hf; BTC is 1,3,5-benzenetricarboxylate) via bimetallic reductive elimination of H2 from putative [M(IV)6(μ3-O)4(μ3-OH)4H12](6-) nodes. The coordinatively unsaturated M(III)H centers in M(III)H-BTC are highly active and selective for 1,4-dearomative hydroboration and hydrosilylation of pyridines and quinolines. This work demonstrated the potential of secondary building unit transformation in generating electronically unique and homogeneously inaccessible single-site solid catalysts for organic synthesis.

  18. Synthesis and characterization of a new photoluminescent material tris (2-methyl-8-hydroxy quinoline) lanthanum La(mq){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rahul, E-mail:; Bhargava, Parag [Department of Metallurgical Engineering and Materials Science Indian Institute of Technology-Bombay, Mumbai-400076 (India)


    A new photoluminescence material, tris (2-methyl-8-hydroxy quinoline) lanthanum has been synthesized and characterized by different techniques. The prepared material La(mq){sub 3} was characterized for structural, thermal and photoluminescence analysis. Structural analysis of this material was done by fourier transformed infrared spectroscopy (FTIR) and mass spectroscopy. Thermal analysis of this material was done by thermal gravimetric analysis (TGA) shows the thermal stability up to 400°C. Absorption and emission spectra of the material was measured by UV-visible spectroscopy and photoluminescence spectroscopy. Solution of this material La(mq){sub 3} in ethanol showed absorption peak at 385 nm respectively which may be attributed due to (π – π*) transitions. The photoluminescence spectra of La(mq){sub 3} in ethanol solution showed intense peak at 430 nm.

  19. Synthesis and characterization of a new photoluminescent material tris (2-methyl-8-hydroxy quinoline) lanthanum La(mq)3 (United States)

    Kumar, Rahul; Bhargava, Parag


    A new photoluminescence material, tris (2-methyl-8-hydroxy quinoline) lanthanum has been synthesized and characterized by different techniques. The prepared material La(mq)3 was characterized for structural, thermal and photoluminescence analysis. Structural analysis of this material was done by fourier transformed infrared spectroscopy (FTIR) and mass spectroscopy. Thermal analysis of this material was done by thermal gravimetric analysis (TGA) shows the thermal stability up to 400°C. Absorption and emission spectra of the material was measured by UV-visible spectroscopy and photoluminescence spectroscopy. Solution of this material La(mq)3 in ethanol showed absorption peak at 385nm respectively which may be attributed due to (π - π*) transitions. The photoluminescence spectra of La(mq)3 in ethanol solution showed intense peak at 430 nm.

  20. New Potential Antimalarial Agents: Design, Synthesis and Biological Evaluation of Some Novel Quinoline Derivatives as Antimalarial Agents

    Directory of Open Access Journals (Sweden)

    Ibrahim Ali M. Radini


    Full Text Available A novel series of dihydropyrimidines (DHPMs 4a–j; 2-oxopyran-3-carboxylate 7a,b; 1-amino-1,2-dihydropyridine-3-carboxylate 8; and 1,3,4-oxadiazole derivatives 12 with quinolinyl residues have been synthesized in fairly good yields. The structure of the newly synthesized compounds was elucidated on the basis of analytical and spectral analyses. In vitro antimalarial evaluation of the synthesized quinoline derivatives against Plasmodium falciparum revealed them to possess moderate to high antimalarial activities, with IC50 values ranging from 0.014–5.87 μg/mL. Compounds 4b,g,i and 12 showed excellent antimalarial activity against to Plasmodium falciparum compared with the antimalarial agent chloroquine (CQ.

  1. Synthesis of Diethyl Pyridin-2-ylphosphonates and Quinolin-2-ylphosphonates by Deoxygenative Phosphorylation of the Corresponding N-Oxides

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sangjin; Kim, Hyunsoo; Yang, Haewon; Yoo, Byungwoo; Yoon, Cheol Min [Korea Univ., Seoul (Korea, Republic of)


    The reaction of pyridine N-oxide and quinoline N-oxide activated by ethyl chloroformate with triethyl phosphites at rt gave the corresponding diethyl pyridin-2-ylphosphonate and diethyl quinolin-2-ylphosphonate regio-selectively in good to excellent yield through oxygenative phosphorylation. The reaction condition is mild and efficient compared to the reported methods. All chemicals including commercially available pyridine N-oxides were purchased from specialized suppliers with analytical purity and used without further purification. Non commercially available pyridine N-oxide for the reaction were prepared by known method. IR spectra of products were recorded on a Perkin-Elmer FT-IR 240-c spectrometer using KBr disks. {sup 1}H NMR (300 MHz) and {sup 13}C NMR (75 MHz) spectra were recorded on a Bruker 300 spectrometer in CDCl{sub 3}. High-resolution ESI-MS spectra were obtained on an IT-TOF (Shimadzu, Japan) at Korea Basic Science Institute (KBSI). Column chromatography was performed using Merck silica gel (230-400 mesh). Some known products have physical, spectroscopic, and analytic data identical to those (shown as a CAS registry number) given in the literature. Dialkyl pyridin-2-ylphosphonates widely used as corrosion inhibitors, dispersing and emulsifying agents, antistatics and lubricant additives in various technological fields are known as potent insecticides, fungicides and herbicides. Pyridin-2-ylphosphonates have also been reported to have a promising cytokinin activity, anti-proliferating and antiplatelet activating factor (anti-PAF) activities, and to be used as a chelate ligand to prepare various metal-organic frameworks, such as polymeric material with Zn, Cd and Ag showing luminescence properties, iron complex as a catalyst and copper complex with weak ferromagnetism. Because biological properties of dialkyl pyridin-2-ylphosphonates and physical properties of their complexes depend both on the phosphorus-containing ligand, simple and efficient

  2. Acetylsalicylic acid and acetaminophen protect against oxidative neurotoxicity. (United States)

    Maharaj, H; Maharaj, D S; Daya, S


    Due to the implication of oxidative stress in neurodegenerative disorders we decided to investigate the antioxidant properties of acetylsalicylic acid and acetaminophen either alone or in combination. The thiobarbituric acid assay (TBA) and the nitroblue tetrazolium (NBT) assay were used to investigate quinolinic acid (QA)-induced: lipid peroxidation and superoxide anion generation in the rat hippocampus, in vivo. The study also shows, using cresyl violet staining, the preservation of structural integrity of neuronal cells following treatment with acetylsalicylic acid and acetaminophen in QA-lesioned rat hippocampus. Furthermore the study sought to determine whether these agents have any effect on endogenous (QA) formation. This study shows that acetylsalicylic acid and acetaminophen inhibit QA-induced superoxide anion generation, lipid peroxidation and cell damage, in vivo, in the rat hippocampus. In addition these agents inhibit the enzyme, 3-hydroxyanthranilic acid oxygenase (3-HAO), responsible for the synthesis of endogenous QA.

  3. Simultaneous preconcentration of vanadium(V/IV) species with palmitoyl quinolin-8-ol bonded to amberlite XAD 2 and their separate spectrophotometric determination with 4-(2-pyridylazo)-resorcinol using CDTA as masking agent

    Energy Technology Data Exchange (ETDEWEB)

    Filik, Hayati; Berker, Kadriye Isil; Balkis, Nuray; Apak, Resat


    This paper reports the simultaneous preconcentration and separation of trace amounts of V species in synthetic solutions and seawater with palmitoyl quinolin-8-ol bonded amberlite XAD 2 copolymer resin column prior to simultaneous speciation analysis. Both V(IV) and V(V) species could be sorbed and preconcentrated by the resin. Both vanadium species were quantitatively eluted together from the resin column using HCl as stripping agent and used for speciation studies. For the speciation analysis of eluted V species, the selected route involved spectrophotometric determination of total vanadium with 4-(2-pyridylazo)-resorcinol (PAR) and vanadate estimation by masking vanadyl with 1,2 cyclohexanediaminetetraacetic acid (CDTA). The preconcentrated V species were assayed spectrophotometrically with PAR at 542 nm, and the results were compared with those of FAAS. The detection limits of V(V) with spectrophotometry and FAAS were 1.6 and 0.9 {mu}g l{sup -1}, respectively. The optimal experimental parameters such as pH, sample flow rate, desorption flow rate, redox behaviour of V(IV) and V(V) in resin and volume of eluent and sample were investigated. The values obtained for the preconcentration factor by the two methods were nearly consistent, and were in the range 150-fold. Analysis of certified reference material (IAEA-405) by the proposed method showed good agreement with the certified value. The established procedure was employed for preconcentrating the vanadium species from artificial and real seawater.

  4. Crystal structure of bis{μ-(E-2-[(2-oxidophenyliminomethyl]quinolin-8-olato-κ4O,N,N′,O′}bis[dibutyltin(IV

    Directory of Open Access Journals (Sweden)

    Camacho-Camacho Carlos


    Full Text Available Condensation of 8-hydroxyquinoline-2-carbaldehyde with 2-aminophenol gave the (E-2-[(2-hydroxyphenyliminomethyl]quinolin-8-ol derivative that reacted with di-n-butyltin oxide with release of H2O to yield the chelate title complex, [Sn2(C4H94(C16H10N2O22]. The compound crystallizes in the triclinic space group P-1, with two independent centrosymmetric dimers in the unit cell. Each features a typical pincer-type structure where the dianionic ligand is tetradentate, coordinating to the central tin atom through both phenolate oxygen atoms, as well as through the quinoline and imine N atoms. Each metal atom adopts a distorted pentagonal–bipyramidal SnC2N2O3 coordination arising from the N,N′,O,O′-tetradentate deprotonated Schiff base, one bridging phenolate O atom of the neighbouring ligand and two butyl groups in the axial sites.

  5. Dichlorido[2-(3,5-dimethyl-1H-pyrazol-1-yl-κN2quinoline-κN]zinc

    Directory of Open Access Journals (Sweden)

    Seik Weng Ng


    Full Text Available The ZnII atom in the title compound, [ZnCl2(C14H13N3], is coordinated by a Cl2N2 donor set defined by quinoline and pyrazole N atoms of the chelating ligand and two Cl atoms. Distortions from the ideal tetrahedral geometry relate to the restricted bite angle of the chelating ligand [N—Zn—N = 78.54 (12°]. In the crystal, molecules are connected into a three-dimensional structure by C—H...Cl interactions, involving both Cl atoms, and π–π interactions that occur between the pyrazole ring and each of the pyridine and benzene rings of the quinoline residue [intercentroid distances = 3.655 (2 and 3.676 (2 Å].

  6. Indium Titanium Oxide Nanoparticles Induced Hepatic Damage: Hepatoprotective Role of Novel 2-Imino-4-methyl-1, 2-Dihydropyrimido [5, 4C] Quinoline-5(6H-one

    Directory of Open Access Journals (Sweden)

    Dinesh Bheeman


    Full Text Available Protective role of 2-imino-4-methyl-1, 2-dihydropyrimido [5, 4C] quinoline-5(6H-one (IMDHPQ in indium titanium oxide nanoparticles (InTiO NPs induced hepatotoxicity was analyzed. InTiO NPs were synthesized and given orally to albino rats to assess their hepatotoxicity. NPs mediated oxidative stress and liver tissue pathology were analyzed. Altered antioxidants (GSH, GPx, and catalase and, biochemical (SGOT, SGPT, ALP, total protein, and total bilirubin and histopathological changes were observed due to the oxidative stress caused by InTiO NPs. Varying effects of IMDHPQ on each parameter were observed in the present study. The altered parameters of InTiO NPs exposed rats might be due to the oxidative stress caused by NPs and hepatoprotective or ameliorative efficacy of quinoline compound IMDHPQ on signaling and molecular mechanism needs further study.

  7. Dichlorido[2-(3,5-dimethyl-1H-pyrazol-1-yl-κN(2))quinoline-κN]zinc. (United States)

    Najib, Muhd Hidayat Bin; Tan, Ai Ling; Young, David J; Ng, Seik Weng; Tiekink, Edward R T


    The Zn(II) atom in the title compound, [ZnCl(2)(C(14)H(13)N(3))], is coordinated by a Cl(2)N(2) donor set defined by quinoline and pyrazole N atoms of the chelating ligand and two Cl atoms. Distortions from the ideal tetra-hedral geometry relate to the restricted bite angle of the chelating ligand [N-Zn-N = 78.54 (12)°]. In the crystal, mol-ecules are connected into a three-dimensional structure by C-H⋯Cl inter-actions, involving both Cl atoms, and π-π inter-actions that occur between the pyrazole ring and each of the pyridine and benzene rings of the quinoline residue [inter-centroid distances = 3.655 (2) and 3.676 (2) Å].

  8. Dehydrogenative [2 + 2 + 1] Heteroannulation Using a Methyl Group as a One-Carbon Unit: Access to Pyrazolo[3,4-c]quinolines. (United States)

    Deng, Guo-Bo; Li, Hai-Bing; Yang, Xu-Heng; Song, Ren-Jie; Hu, Ming; Li, Jin-Heng


    A practical and straightforward access to pyrazolo[3,4-c]quinolines by molecular sieve mediated dehydrogenative [2 + 2 + 1] heteroannulation of N-(o-alkenylaryl)imines with aryldiazonium salts is described using a sp(3)-hybrid carbon atom as a one-carbon unit. The reaction enables the formation of three new chemical bonds, a C-C bond and two C-N bonds, in a single reaction and features simple operation and excellent functional group tolerance.

  9. Star-burst 1H-pyrazolo[3,4-b]quinoline as chromophore for light emitting diodes and photovoltaic devices


    Kityk, Iwan V.; Gondek, Ewa; Danel, Andrzej


    Abstract The current-voltage and electroluminescent features of the novel star-burst 1H-pyrazolo[3,4-b]quinoline chromophore have shown their potential applications as materials for light emitting diodes. The electroluminescence covers the white light spectral range from 420 nm up to 610 nm and achieves maximal value about 18 Cd/m2 at biased voltage 23 V. (Kityk, Iwan V.) (Gondek, Ewa) (Danel, Andrzej) ...

  10. Tandem Reduction/Cyclization of O-Nitrophenyl Propargyl Alcohols-A Novel Synthesis of 2- & 2,4-Disubstituted Quinolines and Application to the Synthesis of Streptonigrin (United States)


    diaminoisophthalaldehyde with p-diacetylbenzene, 2,6-diacetylpyridine, and bis(p-acetyl-phenyl) ether resulted in thermally stable anthrazoline polymers .62 In the...of new methodology to form the heterocyclic ring of quinoline, in a manner that would allow the utilization of palladium-catalyzed coupling of...the past 150 years. This summary will survey the recent work done in the field, focusing on new techniques to generate quinoline’s heterocyclic ring

  11. 3-(2,3,5,6,7,8-Hexahydro-1H-cyclo-penta-[b]quinolin-9-yl)-1,5-bis-(4-methoxy-phen-yl)biuret. (United States)

    Sakurai, Kaori; Noguchi, Keiichi; Nishibe, Koichiro


    Ipidacrine (2,3,5,6,7,8-hexa-hydro-1H-cyclo-penta-[b]quinolin-9-amine) was reacted with 4-methoxy-phenyl isocyanate to give the title compound, C(28)H(30)N(4)O(4). An intra-molecular N-H⋯O hydrogen bond results in an essentially planar [r.m.s. deviation from the mean plane is 0.126 (1) Å] conformation for the biuret unit. The central ring of the quinoline unit is twisted by 78.2 (1)° with respect to the biuret mean plane, whereas the two 4-methoxy-benzene rings are twisted out of this plane by 24.3 (1)° and 48.5 (1)°, resulting in an overall propeller-like structure. An inter-molecular N-H⋯N hydrogen bond between the biuret NH atom and the quinoline ring nitro-gen defines the crystal packing.

  12. Photophysical behavior of a potential drug candidate, trans-[2-(4-methoxystyryl)]quinoline-1-oxide tuned by environment effects (United States)

    Szemik-Hojniak, Anna; Deperasińska, Irena; Nizhnik, Yakov P.


    Styryl and/or quinoline structural fragments, present in a large number of bioactive substances, inspired the design of various new drug candidates. In this paper, we describe the photophysical behavior of trans-[2-(4-methoxystyryl)]quinoline-1-oxide (trans-MSQNO) on the basis of X-ray analysis data, theoretical calculations as well as steady state and time-resolved spectroscopy experiments in various media. The molecule crystallizes in orthorhombic unit cell containing eight molecules of N-oxide, space group Pbca. The Nsbnd O bond is substantially shorter in comparison with the Nsbnd O bond in the ZnTPP unit [1.3052(11) Å vs. 1.335(2) Å]. Variation of emission colors from the violet ( 450 nm) through blue (480 nm), green (525 nm) and yellow (575 nm) is observed in different environments. Comparable values of lifetimes estimated both at ambient temperature and at 77 K suggest that excited state dynamics in this case is viscosity independent. DFT and TD DFT B3LYP/6-31G(d, p) calculations performed for four different trans-MSQNO rotamers in the gas phase, as well as nonpolar and polar media (PCM model) suggest that an equilibrium between them can be significantly altered even by a relatively weak interactions with the environment. It is suggested that varying intensity ratios of experimental absorption bands in different media may be due to the dominant share of one or more rotamers of the excited trans-MSQNO molecule. Gas phase calculations show also that the vertical ππ*, S0 → S1, transition resulting from the HOMO → LUMO electronic configuration exhibits only a partial CT nature. On the other hand, in polar media, a substantial increment of excited state dipole moment of all rotamers compared to the ground state, its increase with increasing solvent polarity and a significant red shift in the absorption and emission spectra, point to the enhanced CT nature of the S1 excited state. Hence, the trans-MSQNO molecule may be considered a subsequent

  13. Unexpected ring-closure products derived from 3-(2-allylanilino)-3-phenylacrylate esters: crystal and molecular structures of 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate and (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one. (United States)

    Luque, Adriana L; Sanabria, Carlos M; Palma, Alirio; Cobo, Justo; Glidewell, Christopher


    The reactions of two 3-(2-allylanilino)-3-phenylacrylate esters with acetic anhydride and with strong acids has revealed a richly diverse reactivity providing a number of unexpected products. Thus, acetylation of ethyl 3-(2-allylanilino)-3-phenylacrylate, (Ia), or ethyl 3-(2-allyl-4-methylanilino)-3-phenylacrylate, (Ib), with acetic anhydride yields not only the expected acetylated esters, (II), as the major products but also the unexpected polysubstituted quinolines 3-acetyl-8-allyl-2-phenylquinolin-4-yl acetate, (IIIa), and 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate, (IIIb), as minor products. Subsequent reaction of the major product ethyl 2-[(2-allyl-4-methylanilino)(phenyl)methylidene]-3-oxobutanoate, (IIb), with concentrated sulfuric acid did not provide the expected 3-acetylquinoline derivative, but instead two unexpected products, namely ethyl 4-ethyl-2-phenyl-1,4-dihydroquinoline-3-carboxylate, (IV), and ethyl 3-acetyl-4-ethyl-2-phenyl-3,4-dihydroquinoline-3-carboxylate, (V), in yields of 39 and 22%, respectively. The reaction of (Ib) with Eaton's reagent gave both the quinoline (Z)-6-methyl-2-phenyl-8-(prop-1-en-1-yl)quinolin-4(1H)-one, (VI), and the unexpected tricyclic product (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one, (VII), in yields of 71 and 12%, respectively. The products (II)-(VII) have all been fully characterized spectroscopically and the crystal structures of two of the unexpected products, i.e. (IIIb) (C23H21NO3) and (VII) (C19H17NO), are reported here. The formation of compounds (IV), (V) and (VII) all require an isomerization of the initial allyl substituent, with migration of the C=C double bond from the terminal site to the internal site. In (IIIb), the two acetyl substituents are oriented such that the intramolecular distance between the two carbonyl O atoms is only 3.243 (2) Å, and in (VII), the five-membered ring adopts a twisted half-chair conformation. The molecules of compound (IIIb

  14. Novel carbazole derivatives with quinoline ring: Synthesis, electronic transition, and two-photon absorption three-dimensional optical data storage (United States)

    Li, Liang; Wang, Ping; Hu, Yanlei; Lin, Geng; Wu, Yiqun; Huang, Wenhao; Zhao, Quanzhong


    We designed carbazole unit with an extended π conjugation by employing Vilsmeier formylation reaction and Knoevenagel condensation to facilitate the functional groups of quinoline from 3- or 3,6-position of carbazole. Two compounds doped with poly(methyl methacrylate) (PMMA) films were prepared. To explore the electronic transition properties of these compounds, one-photon absorption properties were experimentally measured and theoretically calculated by using the time-dependent density functional theory. We surveyed these films by using an 800 nm Ti:sapphire 120-fs laser with two-photon absorption (TPA) fluorescence emission properties and TPA coefficients to obtain the TPA cross sections. A three-dimensional optical data storage experiment was conducted by using a TPA photoreaction with an 800 nm-fs laser on the film to obtain a seven-layer optical data storage. The experiment proves that these carbazole derivatives are well suited for two-photon 3D optical storage, thus laying the foundation for the research of multilayer high-density and ultra-high-density optical information storage materials.

  15. Modeling the Interaction between Quinolinate and the Receptor for Advanced Glycation End Products (RAGE): Relevance for Early Neuropathological Processes (United States)

    Serratos, Iris N.; Castellanos, Pilar; Pastor, Nina; Millán-Pacheco, César; Rembao, Daniel; Pérez-Montfort, Ruy; Cabrera, Nallely; Reyes-Espinosa, Francisco; Díaz-Garrido, Paulina; López-Macay, Ambar; Martínez-Flores, Karina; López-Reyes, Alberto; Sánchez-García, Aurora; Cuevas, Elvis; Santamaria, Abel


    The receptor for advanced glycation end products (RAGE) is a pattern-recognition receptor involved in neurodegenerative and inflammatory disorders. RAGE induces cellular signaling upon binding to a variety of ligands. Evidence suggests that RAGE up-regulation is involved in quinolinate (QUIN)-induced toxicity. We investigated the QUIN-induced toxic events associated with early noxious responses, which might be linked to signaling cascades leading to cell death. The extent of early cellular damage caused by this receptor in the rat striatum was characterized by image processing methods. To document the direct interaction between QUIN and RAGE, we determined the binding constant (Kb) of RAGE (VC1 domain) with QUIN through a fluorescence assay. We modeled possible binding sites of QUIN to the VC1 domain for both rat and human RAGE. QUIN was found to bind at multiple sites to the VC1 dimer, each leading to particular mechanistic scenarios for the signaling evoked by QUIN binding, some of which directly alter RAGE oligomerization. This work contributes to the understanding of the phenomenon of RAGE-QUIN recognition, leading to the modulation of RAGE function. PMID:25757085

  16. Erythrosine B and quinoline yellow dyes regulate DNA repair gene expression in human HepG2 cells. (United States)

    Chequer, Farah Md; Venancio, Vinicius P; Almeida, Mara R; Aissa, Alexandre F; Bianchi, Maria Lourdes P; Antunes, Lusânia Mg


    Erythrosine B (ErB) is a cherry pink food colorant and is widely used in foods, drugs, and cosmetics. Quinoline yellow (QY) is a chinophthalon derivative used in cosmetic compositions for application to the skin, lips, and/or body surface. Previously, ErB and QY synthetic dyes were found to induce DNA damage in HepG2 cells. The aim of this study was to investigate the molecular basis underlying the genotoxicity attributed to ErB and QY using the RT2 Profiler polymerase chain reaction array and by analyzing the expression profile of 84 genes involved in cell cycle arrest, apoptosis, and DNA repair in HepG2 cells. ErB (70 mg/L) significantly decreased the expression of two genes ( FEN1 and REV1) related to DNA base repair. One gene ( LIG1) was downregulated and 20 genes related to ATR/ATM signaling ( ATR, RBBP8, RAD1, CHEK1, CHEK2, TOPB1), nucleotide excision repair ( ERCC1, XPA), base excision repair ( FEN1, MBD4), mismatch repair ( MLH1, MSH3, TP73), double strand break repair ( BLM), other DNA repair genes ( BRIP1, FANCA, GADD45A, REV1), and apoptosis ( BAX, PPP1R15A) were significantly increased after treatment with QY (20 mg/L). In conclusion, our data suggest that the genotoxic mechanism of ErB and QY dyes involves the modulation of genes related to the DNA repair system and cell cycle.

  17. The quinoline-3-carboxamide paquinimod (ABR-215757) reduces leukocyte recruitment during sterile inflammation: leukocyte- and context-specific effects. (United States)

    Deronic, Adnan; Helmersson, Sofia; Leanderson, Tomas; Ivars, Fredrik


    Quinoline-3-carboxamides (Q-compounds) are currently in clinical development for both autoimmune disease and cancer. We have previously shown that the Q-compound paquinimod (ABR-215757) significantly ameliorates disease symptoms in several mouse models of human inflammatory disease. Considering that recruitment of inflammatory cells into tissue is a common denominator of these models, we have in this report investigated whether paquinimod would interfere with cell accumulation during sterile peritoneal inflammation. To mimic the cell recruitment elicited by tissue injury, we used necrotic cells to induce the acute inflammatory response. We show that per oral treatment with paquinimod significantly reduced the accumulation of Ly6C(hi) inflammatory monocytes and eosinophils, but not neutrophils, in this model, and that this correlated with reduced number of such cells also in the omentum. Treatment also reduced the accumulation of these cell populations at a subcutaneous site of inflammation. In alum-induced inflammation, however, neutrophils were the dominant cell population and paquinimod failed to reduce the accumulation of inflammatory cells. Taken together, our results indicate that paquinimod selectively inhibits cell recruitment during acute sterile inflammation, but that this effect is context-dependent. These data have important implications for the understanding of the mechanism of action of Q-compounds in both pre-clinical and clinical settings. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Antioxidant effects of quinoline alkaloids and 2,4-di-tert-butylphenol isolated from Scolopendra subspinipes. (United States)

    Yoon, Mi-Ae; Jeong, Tae-Sook; Park, Doo-Sang; Xu, Ming-Zhe; Oh, Hyun-Woo; Song, Kyoung-Bin; Lee, Woo Song; Park, Ho-Yong


    The oxidized low-density lipoprotein (ox-LDL) plays a critical role at the early stages of atherosclerosis. Thus, the prevention of LDL-oxidation by antioxidants may arrest the progression of atherosclerosis. Two quinoline alkaloids, 3,8-dihydroxyquinoline (1) and 2,8-dihydroxy-3,4-dimethoxyquinoline (3), and 2,4-di-tert-butylphenol (2) were isolated from the dried body of Scolopendra subspinipes. Compounds 1-3 exhibited antioxidant activities on copper-mediated (1: IC50=2.6 microM, 2: IC50=8.2 microM, 3: IC50=63.0 microM), AAPH-mediated oxidation (1: IC50=3.9 microM, 2: IC50=9.9 microM, 3: IC50=71.8 microM), and SIN-1-mediated oxidation (1: 70%, 2: 52%, 3: 29% at 5.0 microM) in the TBARS assay. The antioxidant activities of compounds 1-3 were tested with respect to other parameters, such as the lag time of conjugated diene fromation, relative electrophoretic mobility (REM) of ox-LDL, and apoB-100 fragmentation on copper-mediated LDL-oxidation. In addition, compounds 1-3 showed 1,1-diphenyl-2-picrylhydrasyl (DPPH) radical scavenging activity and compound 1 also exhibited metal chelating activity.

  19. Bifunctional fluorescent benzimidazo[1,2-α]quinolines for Candida spp. biofilm detection and biocidal activity. (United States)

    de Souza, Igor O P; Schrekker, Clarissa M L; Lopes, William; Orru, Romano V A; Hranjec, Marijana; Perin, Nataša; Machado, Michel; Oliveira, Luís F; Donato, Ricardo K; Stefani, Valter; Fuentefria, Alexandre M; Schrekker, Henri S


    Biofilms provide an ideal environment for protecting the microbial cells from damage caused by humoral and cellular immune system components, promoting resistance, infections and increasing mortality and morbidity of patients in health facilities. In an attempt to provide an innovative solution for preventing contamination in hospital environments, this study evaluated nine structural complementary fluorescent benzimidazo[1,2-α]quinolines as bifunctional agents that both detect and have biocidal activity against yeast biofilms on stainless steel surfaces. The benzimidazoles' staining capability was determined by a fluorescence microscopy study and spraying the substance on yeast biofilm contaminated stainless steel surfaces. Furthermore, their in vitro human leukocyte cytotoxicity was evaluated with trypan blue and their biocidal activity was determined as the minimum inhibitory concentration against Candida tropicalis, C. albicans and C. parapsilosis strains. Moreover, scanning electron micrographs were recorded to study the biocidal activity. This resulted in the identification of 7, which presents all the desired characteristics (such as solubility) and capabilities (staining and biocide activity against all tested biofilm forming yeast strains) at the same time. As such, benzimidazole 7 has the potential to guarantee the use of disinfected medical and surgical instruments in clinical and surgical procedures, consequently, contributing to an increased safety for patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Metabolic pathways of quinoline, indole and their methylated analogs by Desulfobacterium indolicum (DSM 3383)

    DEFF Research Database (Denmark)

    Johansen, S.S.; Licht, D.; Arvin, E.


    -quinolinone accumulated. This ring-reduced compound was further transformed into unidentified products. The transformation pathway of indole was characterized by well-known steps through oxindole, isatin, and anthranilic acid. No further transformation of the hydroxylated methyl analogues: 3- and 7...

  1. Palladium-Catalyzed C8-Selective C-H Arylation of Quinoline N-Oxides: Insights into the Electronic, Steric and Solvation Effects on the Site-Selectivity by Mechanistic and DFT Computational Studies. (United States)

    Stephens, David E; Lakey-Beitia, Johant; Atesin, Abdurrahman C; Ateşin, Tülay A; Chavez, Gabriel; Arman, Hadi D; Larionov, Oleg V


    We report herein a palladium-catalyzed C-H arylation of quinoline N-oxides that proceeds with high selectivity in favor of the C8-isomer. This site-selectivity is unusual for palladium, since all of the hitherto described methods of palladium-catalyzed C-H functionalization of quinoline N-oxides are highly C2-selective. The reaction exhibits a broad synthetic scope with respect to quinoline N-oxides and iodoarenes and can be significantly accelerated to sub-hour reaction times under microwave irradiation. The C8-arylation method can be carried out on gram scale and has excellent functional group tolerance. Mechanistic and Density Functional Theory (DFT) computational studies provide evidence for the cyclopalladation pathway and describe key parameters influencing the site-selectivity.

  2. Rapid and Green Analytical Method for the Determination of Quinoline Alkaloids from Cinchona succirubra Based on Microwave-Integrated Extraction and Leaching (MIEL) Prior to High Performance Liquid Chromatography (United States)

    Fabiano-Tixier, Anne-Sylvie; Elomri, Abdelhakim; Blanckaert, Axelle; Seguin, Elisabeth; Petitcolas, Emmanuel; Chemat, Farid


    Quinas contains several compounds, such as quinoline alkaloids, principally quinine, quinidine, cinchonine and cichonidine. Identified from barks of Cinchona, quinine is still commonly used to treat human malaria. Microwave-Integrated Extraction and Leaching (MIEL) is proposed for the extraction of quinoline alkaloids from bark of Cinchona succirubra. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. Optimal conditions for extraction were obtained using a response surface methodology reached from a central composite design. The MIEL extraction has been compared with a conventional technique soxhlet extraction. The extracts of quinoline alkaloids from C. succirubra obtained by these two different methods were compared by HPLC. The extracts obtained by MIEL in 32 min were quantitatively (yield) and qualitatively (quinine, quinidine, cinchonine, cinchonidine) similar to those obtained by conventional Soxhlet extraction in 3 hours. MIEL is a green technology that serves as a good alternative for the extraction of Cinchona alkaloids. PMID:22174637

  3. Enthalpy and phase behavior of coal derived liquid mixtures: Technical progress report for the period January-March 1987. [M-cresol/quinoline/tetralin ternary mixture

    Energy Technology Data Exchange (ETDEWEB)

    Yesavage, V.F.; Kidnay, A.J.


    On July 15, 1984, work was initiated on a program to study the enthalpy and phase behavior of coal derived liquid model compound mixtures. The objectives of this program are to study the enthalpy and phase behavior of a selected ternary model compound system, representative of interactions present in coal derived liquids. Measurements will be made in a Freon 11 reference fluid boil-off calorimeter, and an equilibrium flash vaporization apparatus. These experimental systems have already been developed. Previous studies have indicated that existing data and correlations developed for petroleum fluids are not applicable to coal derived liquids. This is due to the presence of significant concentrations of polar associating heteroatomics in the predominantly aromatic coal liquids. Thus, the ternary system will include an aromatic, a basic nitrogen compound, and a cresol. It is presently planned to study the m-cresol/quinoline/tetralin ternary mixture. Measurements will be made over a wide range of temperature (200 to 750/sup 0/F) and pressure (20 to 1500 psia), for the three pure compounds, the three binary mixtures and selected compositions of the ternary. Both enthalpy and phase behavior measurements will be made. This set of data will be useful as a standard for fitting and evaluating thermodynamic correlations and equations of state that are applicable to associating fluid mixtures, and thus to coal derived liquids. In particular we will attempt to fit both the enthalpy and phase behavior data with a single equation of state using local composition mixing rules and common interaction parameters. During the eleventh quarter, enthalpy measurements have been obtained for the ternary mixtures of m-cresol/quinoline/tetralin with molar ratios 2/3:1/6:1/6 and 1/6:2/3:1/6 m-cresol:quinoline:tetralin. The results are presented in Appendix A. The project has progressed very will during this quarter, and the enthalpy measurements have been completed. 2 refs., 2 figs., 2 tabs.

  4. Synthesis, Characterization and Antimicrobial Activity of Metal Chelates of 5-(4-N, N-Diethylamino sulfonyl phenyl azo-8-hydorxy quinoline

    Directory of Open Access Journals (Sweden)

    A. U. Patel


    Full Text Available 4-N,N-Diethylamino sulfonyl phenyl amine was synthesized by diazotization and coupled with 8-hydroxyquinoline. The resultant 5-(4-N,N-diethylamino sulfonyl phenyl azo-8-hydorxy quinoline (DSAQ was characterized by elemental analysis and spectral studies. The transition metal chelates viz. Cu2+, Ni2+, Co2+, Mn2+ and Zn2+of DSAQ were prepared and characterized by metal-ligand (M:L ratio. IR and reflectance spectroscopy and magnetic properties. The anti fungal activity of DSAQ and its metal chelates was screened against various fungi. The results show that all these samples are good antifungal agents.

  5. 3-[(E)-2-(5,7-Dichloro-8-hydroxy?quinolin-2-yl)vin?yl]-4-hydroxy?phenyl acetate


    Ponikiewski, ?ukasz; Nycz, Jacek E.


    The two symmetry independent mol?ecules of the title compound, C19H13Cl2NO4, show similar conformations with the acetyl group twisted strongly relative to the remaining, virtually flat (r.m.s. deviations = 0.0173 and 0.0065??), part of the mol?ecule. The hydroxyl groups of the 8-hydroxy?quinoline residues are involved in intra?molecular O?H?N hydrogen bonds, which, in one case, forms a part of a three-center inter?action. Inter?molecular O?H?O hydrogen bonds assemble the mol?ecules into a one...

  6. Synthesis and characterization of high quantum yield and oscillator strength 6-chloro-2-(4-cynophenyl)-4-phenyl quinoline (cl-CN-DPQ) organic phosphor for solid-state lighting. (United States)

    Ghate, Minakshi; Dahule, H K; Thejo Kalyani, N; Dhoble, S J


    A novel blue luminescent 6-chloro-2-(4-cynophenyl) substituted diphenyl quinoline (Cl-CN DPQ) organic phosphor has been synthesized by the acid-catalyzed Friedlander reaction and then characterized to confirm structural, optical and thermal properties. Structural properties of Cl-CN-DPQ were analyzed by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction technique (XRD) and scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDAX) spectroscopy. FTIR spectra confirmed the presence of different functional groups and bond stretching. 1 H-NMR and 13 C-NMR confirmed the formation of an organic Cl-CN-DPQ compound. X-ray diffraction study provided its crystalline nature. The surface morphology of Cl-CN-DPQ was analyzed by SEM, while EDAX spectroscopy revealed the elemental analysis. Differential thermal analysis (TGA/DTA) disclosed its thermal stability up to 250°C. The optical properties of Cl-CN-DPQ were investigated by UV-vis absorption and photoluminescence (PL) measurements. Cl-CN-DPQ exhibits intense blue emission at 434 nm in a solid-state crystalline powder with CIE co-ordinates (0.157, 0.027), when excited at 373 nm. Cl-CN-DPQ shows remarkable Stokes shift in the range 14800-5100 cm-1 , which is the characteristic feature of intense light emission. A narrow full width at half-maximum (FWHM) value of PL spectra in the range 42-48 nm was observed. Oscillator strength, energy band gap, quantum yield, and fluorescence energy yield were also examined using UV-vis absorption and photoluminescence spectra. These results prove its applications towards developing organic luminescence devices and displays, organic phosphor-based solar cells and displays, organic lasers, chemical sensors and many more. Copyright © 2017 John Wiley & Sons, Ltd.

  7. Facile Synthesis of 5, 6, 7, 8-Tetrahydropyrimido [4, 5-b]-quinoline Derivatives

    Directory of Open Access Journals (Sweden)

    Mohamed Abdelhamed Morsy


    Full Text Available 2–Amino–4-phenyl–5,6,7,8–tetrahydroquinoline–3–carbonitrile (3 was synthesized by treating cyclohexanone (1 with 2–benzylidenemalononitrile (2 in the presence of ammonium acetate. The reactivity of compound 3 towards dimethylformamide dimethyl acetal (DMF-DMA, carbon disulfide, urea, thiourea, formamide, formic acid, acetyl chloride and isothiocyanate were studied. In addition, the antimicrobial activity of some selected derivatives is reported.

  8. Synthesis of novel quinolines using TsOH/ionic liquid under microwave

    Energy Technology Data Exchange (ETDEWEB)

    Prola, Lizie D.T.; Buriol, Lilian; Frizzo, Clarissa P.; Caleffi, Guilherme S.; Marzari, Mara R.B.; Moreira, Dayse N.; Bonacorso, Helio G.; Zanatta, Nilo; Martins, Marcos A.P., E-mail: [Nucleo de Quimica de Heterociclos (NUQUIMHE), Departamento de Quimica, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS (Brazil)


    In this work, 3-haloacetyl-4-methylquinolines were synthesized from the reaction of 4-alkoxy-3-alkene-2-ones [R{sup 1}C(O)CH=C(R{sup 2})OCH{sub 3}, where R{sup 1} = CF{sub 3}, CCl{sub 3}, CHCl{sub 2}, CF{sub 2}Cl, CF{sub 2}CF{sub 3}and R{sub 2}= Me, Et, Pr, Bu, i-Bu and i-Pe] and 2-aminoacetophenone. The reaction was performed in ionic liquid and 4-toluene sulfonic acid under microwave irradiation. Results showed that the catalytic method was effective. Products were formed in a short time (10-20 min) and presented good yields (70-91%). (author)

  9. 7-deoxyloganetic acid synthase catalyzes a key 3 step oxidation to form 7-deoxyloganetic acid in Catharanthus roseus iridoid biosynthesis. (United States)

    Salim, Vonny; Wiens, Brent; Masada-Atsumi, Sayaka; Yu, Fang; De Luca, Vincenzo


    Iridoids are key intermediates required for the biosynthesis of monoterpenoid indole alkaloids (MIAs), as well as quinoline alkaloids. Although most iridoid biosynthetic genes have been identified, one remaining three step oxidation required to form the carboxyl group of 7-deoxyloganetic acid has yet to be characterized. Here, it is reported that virus-induced gene silencing of 7-deoxyloganetic acid synthase (7DLS, CYP76A26) in Catharanthus roseus greatly decreased levels of secologanin and the major MIAs, catharanthine and vindoline in silenced leaves. Functional expression of this gene in Saccharomyces cerevisiae confirmed its function as an authentic 7DLS that catalyzes the 3 step oxidation of iridodial-nepetalactol to form 7-deoxyloganetic acid. The identification of CYP76A26 removes a key bottleneck for expression of iridoid and related MIA pathways in various biological backgrounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Synthesis, antibacterial and anti-MRSA activity, in vivo toxicity and a structure-activity relationship study of a quinoline thiourea. (United States)

    Dolan, Niamh; Gavin, Declan P; Eshwika, Ahmed; Kavanagh, Kevin; McGinley, John; Stephens, John C


    We report the synthesis, antibacterial evaluation of a series of thiourea-containing compounds. 1-(3,5-Bis(trifluoromethyl)phenyl)-3-((S)-(6-methoxyquinolin-4-yl)-((1S,2S,4S,5R)-5-vinylquinuclidin-2-yl)methyl)thiourea 5, was the most active against a range of Gram-positive and Gram-negative bacteria, and exhibited bacteriostatic activity against methicillin resistant Staphylococcus aureus (MRSA) comparable to that of the well-known antibacterial agent vancomycin. Quinoline thiourea 5 was subjected to a detailed structure-activity relationship study, with 5 and its derivatives evaluated for their bacteriostatic activity against both Gram-negative and Gram-positive bacteria. A number of structural features important for the overall activity of quinoline thiourea 5 have been identified. A selection of compounds, including 5, was also evaluated for their in vivo toxicity using the larvae of the Greater wax moth, Galleria mellonella. Compound 5, and a number of derivatives, were found to be non-toxic to the larvae of Galleria mellonella. A new class of antibiotic can result from the further development of this family of compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Synthesis and crystal structure of tetra(quinolin-8-olatothorium ethanol solvate, Th(C9H6NO4*C2H5OH

    Directory of Open Access Journals (Sweden)

    Holger Kohlmann


    Full Text Available Metal quinolinolates (also known as oxinates have been widely used for gravimetric analysis and in recent days as materials for organic light emitting diodes (OLEDs. Recrystallisation of tetra(quinolin-8- olatothorium(IV (ThQ4 yielded yellow, translucent, prismatic crystals of the title compound, ThQ4*C2H5OH, the single-crystal structure of which is described. Only one crystallographically distinct molecule is found, all ligands are crystallographically inequivalent. Thorium is coordinated by four 8-hydroxyquinolinato with average Th-O distances of 233.3 pm and average Th-N distances of 272.4 pm, and one ethanol ligand with a Th-O distance 256.7 pm. O and N surroundings around thorium can be described by a tricapped trigonal prism. In contrast to quinolinates of the trivalent metals, ThQ4*C2H5OH does not fluoresce under UV irradiation, which is in accordance with the lack of π-π overlap in the crystal structure.

  12. Computational and Experimental Study on Molecular Structure of Benzo[g]pyrimido[4,5-b]quinoline Derivatives: Preference of Linear over the Angular Isomer

    Directory of Open Access Journals (Sweden)

    Jorge Trilleras


    Full Text Available A series of 5-aryl-2-methylthio-5,12-dihydrobenzo[g]pyrimido[4,5-b]quinoline-4,6,11(3H-trione was synthesized through an environmental friendly multicomponent methodology and characterized with FT-IR (Fourier Transform infrared spectroscopy, 1H NMR (Nuclear Magnetic Resonance , 13C NMR and GC-MS (gas chromatography-mass spectrometry. The 5-(4-methoxyphenyl-2-methylthio-5,12-dihydrobenzo[g]pyrimido[4,5-b]quinoline-4,6,11(3H-trione 4c compound was characterized by X-ray single crystal diffraction. The geometry of 4c has been fully optimized using DFT (Density functional theory, B3LYP functional and 6-31G(d,p basis set, thus establishing the ground state energy and thermodynamic features for the mentioned compound, which are in accordance with the experimental data and the crystal structure. The experimental results reveal a strong preference for the regioselective formation of 4c linear four fused rings over the angular four fused and suggest a possible kinetic control in product formation.

  13. A highly selective and sensitive turn-on probe for aluminum(III) based on quinoline Schiff's base and its cell imaging (United States)

    Zhou, Fenfen; Wang, Hongqing; Liu, Pengying; Hu, Qinghua; Wang, Yuyuan; Liu, Can; Hu, Jiangke


    A reversible Schiff's base fluorescence probe for Al3+, (3,5-dichloro-2- hydroxybenzylidene) quinoline-2-carbohydrazide (QC), based on quinoline derivative has been designed, synthesized and evaluated. The QC exhibited a high sensitivity and selectivity toward Al3+ in EtOH-H2O (v/v = 1:9, pH = 6) by forming a 1:1 complex with Al3+ and the detection limit of QC for Al3+ was as low as 0.012 μM. Furthermore, these results displayed that the binding of QCsbnd Al3+ was broken by F-, so this system could be used to monitor F- in the future. The enhancement fluorescence of the QC could be attributed to the inhibition of PET and ESIPT and the emergency of CHEF process induced by Al3+. More importantly, QC was not only successfully used for the determination of trace Al3+ in the tap water and the human blood serum, but was valid for fluorescence imaging of Al3+ in the Hela cells.

  14. catena-Poly[disilver(I)(Ag-Ag)-bis-(μ(3)-quinoline-3-carboxyl-ato)-1:2:1'κ(3)O:O':N;2:1'':2''κ(3)N:O:O'

    National Research Council Canada - National Science Library

    Liu, Chun-Bo; Cong, Yao; Sun, He-Yi


    In the title compound, [Ag(2)(C(10)H(6)NO(2))(2)](n), the Ag(I) atom is coordinated by one N atom and two O atoms from three quinoline-3-carboxyl-ate ligands in a T-shaped fashion, with an additional Ag⋯Ag distance of 2.9468 (6) Å...

  15. Effect of quinoline based 1,2,3-triazole and its structural analogues on growth and virulence attributes of Candida albicans.

    Directory of Open Access Journals (Sweden)

    Mohammad Irfan

    Full Text Available Candida albicans, along with some other non-albicans Candida species, is a group of yeast, which causes serious infections in humans that can be both systemic and superficial. Despite the fact that extensive efforts have been put into the discovery of novel antifungal agents, the frequency of these fungal infections has increased drastically worldwide. In our quest for the discovery of novel antifungal compounds, we had previously synthesized and screened quinoline containing 1,2,3-triazole (3a as a potent Candida spp inhibitor. In the present study, two structural analogues of 3a (3b and 3c have been synthesized to determine the role of quinoline and their anti-Candida activities have been evaluated. Preliminary results helped us to determine 3a and 3b as lead inhibitors. The IC50 values of compound 3a for C. albicans ATCC 90028 (standard and C. albicans (fluconazole resistant strains were 0.044 and 2.3 μg/ml, respectively while compound 3b gave 25.4 and 32.8 μg/ml values for the same strains. Disk diffusion, growth and time kill curve assays showed significant inhibition of C. albicans in the presence of compounds 3a and 3b. Moreover, 3a showed fungicidal nature while 3b was fungistatic. Both the test compounds significantly lower the secretion of proteinases and phospholipases. While, 3a inhibited proteinase secretion in C. albicans (resistant strain by 45%, 3b reduced phospholipase secretion by 68% in C. albicans ATCC90028 at their respective MIC values. Proton extrusion and intracellular pH measurement studies suggested that both compounds potentially inhibit the activity of H+ ATPase, a membrane protein that is crucial for various cell functions. Similarly, 95-97% reduction in ergosterol content was measured in the presence of the test compounds at MIC and MIC/2. The study led to identification of two quinoline based potent inhibitors of C. albicans for further structural optimization and pharmacological investigation.

  16. Effect of quinoline based 1,2,3-triazole and its structural analogues on growth and virulence attributes of Candida albicans. (United States)

    Irfan, Mohammad; Alam, Shadab; Manzoor, Nikhat; Abid, Mohammad


    Candida albicans, along with some other non-albicans Candida species, is a group of yeast, which causes serious infections in humans that can be both systemic and superficial. Despite the fact that extensive efforts have been put into the discovery of novel antifungal agents, the frequency of these fungal infections has increased drastically worldwide. In our quest for the discovery of novel antifungal compounds, we had previously synthesized and screened quinoline containing 1,2,3-triazole (3a) as a potent Candida spp inhibitor. In the present study, two structural analogues of 3a (3b and 3c) have been synthesized to determine the role of quinoline and their anti-Candida activities have been evaluated. Preliminary results helped us to determine 3a and 3b as lead inhibitors. The IC50 values of compound 3a for C. albicans ATCC 90028 (standard) and C. albicans (fluconazole resistant) strains were 0.044 and 2.3 μg/ml, respectively while compound 3b gave 25.4 and 32.8 μg/ml values for the same strains. Disk diffusion, growth and time kill curve assays showed significant inhibition of C. albicans in the presence of compounds 3a and 3b. Moreover, 3a showed fungicidal nature while 3b was fungistatic. Both the test compounds significantly lower the secretion of proteinases and phospholipases. While, 3a inhibited proteinase secretion in C. albicans (resistant strain) by 45%, 3b reduced phospholipase secretion by 68% in C. albicans ATCC90028 at their respective MIC values. Proton extrusion and intracellular pH measurement studies suggested that both compounds potentially inhibit the activity of H+ ATPase, a membrane protein that is crucial for various cell functions. Similarly, 95-97% reduction in ergosterol content was measured in the presence of the test compounds at MIC and MIC/2. The study led to identification of two quinoline based potent inhibitors of C. albicans for further structural optimization and pharmacological investigation.

  17. Novel iridium(III) complexes based on 2-(2,2’-bithien-5-yl)-quinoline. Synthesis, photophysical, photochemical and DFT studies

    Energy Technology Data Exchange (ETDEWEB)

    Szafraniec-Gorol, Grażyna, E-mail: [Institute of Chemistry, Faculty of Mathematics, Physics and Chemistry, University of Silesia, Szkolna 9, 40-007 Katowice (Poland); Słodek, Aneta; Filapek, Michał [Institute of Chemistry, Faculty of Mathematics, Physics and Chemistry, University of Silesia, Szkolna 9, 40-007 Katowice (Poland); Boharewicz, Bartosz; Iwan, Agnieszka [Electrotechnical Institute, Division of Electrotechnology and Materials Science, M. Sklodowskiej-Curie 55/61, 50-369 Wroclaw (Poland); Jaworska, Maria; Żur, Lidia; Sołtys, Marta; Pisarska, Joanna; Grudzka-Flak, Iwona [Institute of Chemistry, Faculty of Mathematics, Physics and Chemistry, University of Silesia, Szkolna 9, 40-007 Katowice (Poland); Czajkowska, Sylwia [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, 41-819 Zabrze (Poland); Sojka, Maciej; Danikiewicz, Witold [Institute of Organic Chemistry, Polish Academy of Science, Kasprzaka 44/52, 01-224 Warsaw (Poland); Krompiec, Stanisław [Institute of Chemistry, Faculty of Mathematics, Physics and Chemistry, University of Silesia, Szkolna 9, 40-007 Katowice (Poland)


    Four novel cyclometalated iridium(III) complexes: [Ir(q-bt-Ph){sub 2}(phen)]PF{sub 6}, [Ir(q-bt-Ph){sub 2}(acac)], [Ir(q-bt-Me){sub 2}(bpy)]PF{sub 6} and [Ir(q-bt-Me){sub 2}(acac)] (where q-bt-Ph, q-bt-Me correspond to 2-(2,2’-bithien-5-yl)-4-phenylquinoline and 2-(2,2’-bithien-5-yl)-4-methylquinoline), are reported. The complexes were characterized by NMR, FTIR and HRMS. The optical, electrochemical properties and thermal stability of novel iridium(III) complexes were thoroughly investigated. The complexes emit a light in the narrow range of 693–707 nm. The optical study showed that replacement of fragment in the main quinoline ligand did not affect wavelength of the emitted light. On the other hand, the modification of the ancillary ligand and substituent in the quinoline ring caused the increase of the photoluminescence quantum yields. Electrochemical experiments demonstrate that the oxidation process for complexes [Ir(q-bt-Ph){sub 2}(phen)]PF{sub 6} and [Ir(q-bt-Ph){sub 2}(acac)] was reversible (or quasi-reversible) and well detectable whereas for complexes with quinoline substituted by methyl group was irreversible, even at low temperature (−70 °C). The electrochemical and photophysical studies have been well confirmed by density functional theory (DFT) calculations. In addition, bulk heterojunction polymer solar cells based on complexes [Ir(q-bt-Ph){sub 2}(phen)]PF{sub 6} and [Ir(q-bt-Ph){sub 2}(acac)] were fabricated. Only the solar cell incorporating [Ir(q-bt-Ph){sub 2}(acac)] exhibited a photovoltaic effect. The architecture of the cell was ITO/PEDOT:PSS/P3HT:PCBM:[Ir(q-bt-Ph){sub 2}(acac)]/Al. A power conversion efficiency of 0.25% was measured under 1 sun illumination using an AM 1.5G filter to simulate the solar spectrum. - Graphical abstract: Display Omitted - Highlights: • Iridium(III) complexes bearing 2-bithienylquinolines as main ligands were examined. • Optical and electrochemical measurements were compared with DFT calculations.

  18. Synthesis and crystal structure of bis(1-{[(quinolin-8-ylimino]methyl}pyrene-κ2N,N′silver(I trifluoromethanesulfonate

    Directory of Open Access Journals (Sweden)

    Miguel Pinto


    Full Text Available The title compound, [Ag(qPyr2]CF3SO3 where qPyr = 1-(quinoline-2-ylmethyleneaminopyrene, C26H16N2, was synthesized from a reaction of silver trifluoromethanesulfonate and qPyr in dichloromethane–methanol mixed media. In this design, the qPyr ligand was chosen for its characteristic excitation and emission profiles, which could enable the tracking of the silver complex within biological targets. The AgI atom resides in a distorted tetrahedral N4 coordination sphere. Analysis of the packing pattern revealed significant intra- and intermolecular π–π stacking interactions between the [Ag(qPyr2]+ cations. In addition, a weak C—H...O hydrogen bond consolidates the packing between cations and anions.

  19. IQ (2-amino-3-methylimidazo[4,5-f]quinoline)- induced aberrant crypt foci and colorectal tumour development in rats fed two different carbohydrate diets

    DEFF Research Database (Denmark)

    Mølck, A.M.; Meyer, Otto A.; Kristiansen, E.


    In most aberrant crypt foci (ACF) and colorectal tumour studies, chemical carcinogens not normally found in food have been used as initiators. In the present study the food-related compound, IQ (2-amino-3-methylimidazo[4,5-f]quinoline), has been used. A diet high in refined carbohydrates has been...... on the development of IQ-induced ACF over time and (2) possible correlation between early and late ACF and/or colorectal tumour development. The study showed that a feeding regimen with continuous doses of 0.03% IQ in the diet for 14 weeks, followed by 32 weeks without IQ was able to induce tumours in the rat colon...

  20. Some spirobiindane based 1H-pyrazolo [3,4-b] quinoline chromophore as novel chromophore for light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Gondek, E. [Institute of Physics, Cracow University of Technology, Podchorazych 1, 30-084 Krakow (Poland); Danel, A. [Department of Chemistry and Physics, Agricultural University of Krakow, Balicka 122, Krakow 31-149 (Poland); NizioL, J. [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, Krakow (Poland); Armatys, P. [Military Technical Academy of Warsaw, ul. Kaliska 4, Warsaw (Poland); Kityk, I.V., E-mail: ikityk@el.pcz.czest.p [Electrical Engineering Department, Czestochcowa University of Technology, Armii Krajowej 17, PL-42-201 (Poland); Szlachcic, P. [Department of Chemistry and Physics, Agricultural University of Krakow, Balicka 122, Krakow 31-149 (Poland); Karelus, M.; Uchacz, T.; Chwast, J. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Lakshminarayana, G. [Department of Materials Science and Engineering, Nagoya Institute of Technology, Showa, Nagoya 466-8555 (Japan)


    An influence of phenoxy groups for the luminescent and electroluminescent properties of spiro-compounds with pyrazolo [3,4-b] quinoline structure (fluorophore) chromophore has been studied. All the compounds exhibit strong fluorescence in solution and in solid state as well. The prepared compounds were used as dopant chromophore in PVK polymer matrices for electroluminescent (EL) and light-emitting diode (LED) devices with configuration ITO/PEDOT-PSS/PVK/PQ/Ca/Al. Role of the bathochromic shifts and solvent polarity in absorption and photoluminescent maxima is considered. Relation between the number of pyrazoloquinoline chromophore and presence of phenyl group on the fluorescence spectra is explored. Polarizability of the particular pyrazoloquinoline compounds on the solvatochromic effects is investigated. Possible ways of enhancement of the brightness in the light-emitting properties of the mentioned chromophore are discussed.

  1. Synthesis and characterization of a new photoluminescent material (8-hydroxy quinoline) bis (2-2’bipyridine) lanthanum La(Bpy)2q

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rahul, E-mail:; Bhargava, Parag [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology-Bombay, Mumbai-400076 (India)


    A new photoluminescence material, (8-hydroxy quinoline) bis (2-2’bipyridine) lanthanum has been synthesized and characterized by different techniques. The prepared material La(Bpy){sub 2}q was characterized for structural, thermal and photoluminescence analysis. Structural analysis of this material was done by Fourier transformed infrared spectroscopy (FTIR) and mass spectroscopy. Thermal analysis of this material was done by thermal gravimetric analysis (TGA) shows the thermal stability up to 190°C.Absorption and emission spectra of the material was measured by UV-visible spectroscopy and photoluminescence spectroscopy. Solution of this material La(Bpy){sub 2}q in ethanol showed absorption peak at 385nm, which may be attributed due to (π – π*) transitions. The photoluminescence spectra of La(Bpy){sub 2}q in ethanol solution showed intense peak at 490 nm.

  2. Synthesis and characterization of a new photoluminescent material (8-hydroxy quinoline) bis (2-2'bipyridine) lanthanum La(Bpy)2q (United States)

    Kumar, Rahul; Bhargava, Parag


    A new photoluminescence material, (8-hydroxy quinoline) bis (2-2'bipyridine) lanthanum has been synthesized and characterized by different techniques. The prepared material La(Bpy)2q was characterized for structural, thermal and photoluminescence analysis. Structural analysis of this material was done by Fourier transformed infrared spectroscopy (FTIR) and mass spectroscopy. Thermal analysis of this material was done by thermal gravimetric analysis (TGA) shows the thermal stability up to 190°C.Absorption and emission spectra of the material was measured by UV-visible spectroscopy and photoluminescence spectroscopy. Solution of this material La(Bpy)2q in ethanol showed absorption peak at 385nm, which may be attributed due to (π - π*) transitions. The photoluminescence spectra of La(Bpy)2q in ethanol solution showed intense peak at 490 nm

  3. μ2-Iodido-bis{dimethyl[methylbis(quinolin-8-ylsilanyl-κ3N,Si,N′]platinum(IV} tetrakis(pentafluorophenylborate dichloromethane 0.66-solvate

    Directory of Open Access Journals (Sweden)

    Marcus I. Gibson


    Full Text Available The title complex, [Pt2(CH34(C19H15N2Si2I][B(C6F54]·0.66CH2Cl2, resulted from an attempt to synthesize a stable five-coordinate platinum species via ligand abstraction of a six-coordinate platinum precursor. However, dimerization occurred after ligand abstraction, thereby yielding the compound described in this study. The cation is a dinuclear PtIV organometallic complex, in which the metal centers are bridged by an I− anion. Both metal centers display a coordination geometry close to octahedral, including cis-arranged quinoline ligands connected by Si atoms, which form Pt—Si bonds, two cis-methyl groups, and the bridging I− anion. In the crystal structure, voids between cations and anions are partially filled with an average of 0.66 molecules of dichloromethane solvent.

  4. Anti-cancer agents based on N-acyl-2, 3-dihydro-1H-pyrrolo[2,3-b] quinoline derivatives and a method of making (United States)

    Gakh, Andrei; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V


    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. In particular, the invention relates to N-acyl derivatives of 2,3-dihydro-1H-pyrrolo[2,3-b]quinolines having the structural Formula (I), ##STR00001## stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. The meaning of R1 is independently selected from H; C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl substituents; R2 is selected from C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl; substituted or non-substituted, fused or non-fused to substituted or non-substituted aromatic ring, aryl or heteroaryl groups. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  5. 3-[(E)-2-(5,7-Dichloro-8-hydroxy­quinolin-2-yl)vin­yl]-4-hydroxy­phenyl acetate (United States)

    Ponikiewski, Łukasz; Nycz, Jacek E.


    The two symmetry independent mol­ecules of the title compound, C19H13Cl2NO4, show similar conformations with the acetyl group twisted strongly relative to the remaining, virtually flat (r.m.s. deviations = 0.0173 and 0.0065 Å), part of the mol­ecule. The hydroxyl groups of the 8-hydroxy­quinoline residues are involved in intra­molecular O—H⋯N hydrogen bonds, which, in one case, forms a part of a three-center inter­action. Inter­molecular O—H⋯O hydrogen bonds assemble the mol­ecules into a one-dimensional polymeric structure extended along the a axis. The 4-hydroxy­phenyl group of one mol­ecule forms an O—H⋯O hydrogen bond, in which the hydroxyl H atom is disordered, with its inversion center counterpart. PMID:21582178

  6. 3-[(E)-2-(5,7-Dichloro-8-hydroxy-quinolin-2-yl)vin-yl]-4-hydroxy-phenyl acetate. (United States)

    Ponikiewski, Lukasz; Nycz, Jacek E


    The two symmetry independent mol-ecules of the title compound, C(19)H(13)Cl(2)NO(4), show similar conformations with the acetyl group twisted strongly relative to the remaining, virtually flat (r.m.s. deviations = 0.0173 and 0.0065 Å), part of the mol-ecule. The hydroxyl groups of the 8-hydroxy-quinoline residues are involved in intra-molecular O-H⋯N hydrogen bonds, which, in one case, forms a part of a three-center inter-action. Inter-molecular O-H⋯O hydrogen bonds assemble the mol-ecules into a one-dimensional polymeric structure extended along the a axis. The 4-hydroxy-phenyl group of one mol-ecule forms an O-H⋯O hydrogen bond, in which the hydroxyl H atom is disordered, with its inversion center counterpart.

  7. Neuroprotection in rabbit retina with N-acetyl-aspartylglutamate and 2-phosphonyl-methyl pentanedioic acid (United States)

    Hacker, Henry D.; Yourick, Debra L.; Koenig, Michael K.; Slusher, Barbara S.; Meyerhoff, James L.


    Retinal tissue is subject to ischemia from diabetic retinopathy and other conditions that affect the retinal vasculature such as lupus erythematosus and temporal arteritis. There is evidence in animal models of reversible ischemia that a therapeutic window exists during early recovery when agents that reduce glutamate activity at its receptor sites can rescue neurons from injury. To model ischemia, we used sodium cyanide (NaCN), to inhibit oxidative metabolism, and 2-deoxyglucose (2-DG) to inhibit glycolysis. Dissociated rabbit retina cells were studied to evaluate the potential neuroprotective effects of N-acetyl-aspartyl-glutamate (MAAG), which competes with glutamate as a low-potency agonist at the NMDA receptor complex. N-acetylated α-linked acidic dipeptidase (NAALADase; the NAAG-hydrolyzing enzyme) is responsible for the hydrolysis of NAAG into glutamate, a neurotransmitter and potent excitotoxin, and N-acetylaspartate. 2-Phosphonyl-methyl pentanedioic acid (PMPA) and β-linked NAAG (β-NAAG), inhibitors of NAALADase, were also tested, since inhibition of NAALADase could reduce synaptic glutamate and increase the concentration of NAAG. We found that metabolic inhibition with NaCN/2-DG for 1 hour caused 50% toxicity as assessed with the MTT assay. Co-treatment with NAAG resulted in dose-dependent protection of up to 55% (pobserved (p<0.001). PMPA also showed 48% protection (p<.05-.001) against these insults. These data suggest that NAAG may antagonize the effect of glutamate at the NMDA receptor complex in retina. Inhibition of NAALADase by PMPA and β-NAAG may increase the activity of endogenous NAAG.

  8. Practical and Efficient Synthesis of α-Aminophosphonic Acids Containing 1,2,3,4-Tetrahydroquinoline or 1,2,3,4-Tetrahydroisoquinoline Heterocycles

    Directory of Open Access Journals (Sweden)

    Mario Ordóñez


    Full Text Available We report here a practical and efficient synthesis of α-aminophosphonic acid incorporated into 1,2,3,4-tetrahydroquinoline and 1,2,3,4-tetrahydroisoquinoline heterocycles, which could be considered to be conformationally constrained analogues of pipecolic acid. The principal contribution of this synthesis is the introduction of the phosphonate group in the N-acyliminium ion intermediates, obtained from activation of the quinoline and isoquinoline heterocycles or from the appropriate δ-lactam with benzyl chloroformate. Finally, the hydrolysis of phosphonate moiety with simultaneous cleavage of the carbamate afforded the target compounds.

  9. 2-Hydrazinyl-quinoline. (United States)

    Najib, Muhd Hidayat Bin; Tan, Ai Ling; Young, David J; Ng, Seik Weng; Tiekink, Edward R T


    In the title compound, C(9)H(9)N(3), the 12 non-H atoms are essentially planar (r.m.s. deviation = 0.068 Å). The maximum deviation from planarity is reflected in the torsion angle between the β-N atom of the hydrazinyl residue and the quinolinyl N atom [N-N-C-N = -12.7 (3)°]; these atoms are syn. In the crystal, supra-molecular layers in the bc plane are formed via N-H⋯N hydrogen bonds.

  10. Synthesis of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-ones and their 2-methylene derivatives as potential spermicidal and microbicidal agents. (United States)

    Pandey, Rishi Ranjan; Srivastava, Akansha; Malasoni, Richa; Naqvi, Arshi; Jain, Ashish; Maikhuri, Jagdamba Prasad; Paliwal, Sarvesh; Gupta, Gopal; Dwivedi, Anil Kumar


    A series of twenty two derivatives of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one and their 2-methylene derivatives were synthesized from naturally abundant cinchonine (I). Tartarate salts of these compounds were prepared and evaluated for spermicidal activity. The most active compounds (24, 27, 34, 36, and 38) showing potent spermicidal activity were further evaluated against different strains of Trichomonas vaginalis, for antimicrobial activity, in HeLa cell lines for cytotoxicity and against Lactobacillus jensenii for eco-safety. The tartarate of 3-(1-pentyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one (27) was found to be more active than N-9 in spermicidal activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Catalytic Synthesis of 3-Methyl-1-phenyl-1H-benzo[g]pyrazolo[3,4-b]quinoline-5,10-dione Derivatives Using Cerium Oxide Nanoparticles as Heterogeneous Catalyst in Green Conditions

    Directory of Open Access Journals (Sweden)

    Ali Gharib


    Full Text Available We have developed a new methodology for the synthesis of 3-methyl-1-phenyl-1H-benzo[g]pyrazolo[3,4-b]quinoline-5,10-dione derivatives in excellent yields. A new green chemistry protocol with the reusability of the nanoparticle as catalyst has been developed for the synthesis of 3-methyl-1-phenyl-1H-benzo[g]pyrazolo[3,4-b]quinoline-5,10-dione derivatives via one-pot reaction of 3-methyl-1-phenyl-1H-pyrazol-5-amine, arylaldehydes, and 2-hydroxynaphthalene-1,4-dione in water as green solvent and using cerium oxide nanoparticles (CONPs as heterogeneous catalyst. The present methodology affords several advantages such as simple procedure, excellent yields, and short reaction time. The catalyst is inexpensive, stable, easily recycled, and reused for several cycles with consistent activity.

  12. Synthesis and docking analysis of new heterocyclic system of tetrazolo[5',1':2,3][1,3,4]thiadiazepino [7,6-b]quinolines as aldose reductase inhibitors

    Directory of Open Access Journals (Sweden)

    Mohammad Saadatmandzadeh


    Conclusion: All of the best models formed strong hydrogen bonds with Trp 111 and Tyr 209 via tetrazole moiety. It was found that pi-pi interaction between Tyr 209, Trp 20 and His 110 side chain and quinolin moiety was one of the common factors in enzyme-inhibitor junction. It was found that both hydrogen bonding and hydrophobic interactions are important in the structure and function of biological molecules, especially for inhibition in a complex.

  13. Synthesis and characterization of new 3-(4,5-dihydro-5-arylisoxazol-3-yl-4-hydroxyquinolin-2(1H-ones and 3-(4-styrylisoxazolo[4,5-c]quinolin-4(5H-one derivatives

    Directory of Open Access Journals (Sweden)

    S. Sarveswari


    Full Text Available The 4-hydroxy-3-(3-arylacryloylquinolin-2(1H-ones were synthesized from 3-acetyl-4-hydroxyquinolin-2(1H-one by microwave assisted synthesis, which in turn converted into their corresponding 3-(4,5-dihydro-5-arylisoxazol-3-yl-4-hydroxyquinolin-2(1H-ones and 3-(4-styrylisoxazolo[4,5-c]quinolin-4(5H-one derivatives.

  14. 3-(2,3,5,6,7,8-Hexahydro-1H-cyclo­penta­[b]quinolin-9-yl)-1,5-bis­(4-methoxy­phen­yl)biuret (United States)

    Sakurai, Kaori; Noguchi, Keiichi; Nishibe, Koichiro


    Ipidacrine (2,3,5,6,7,8-hexa­hydro-1H-cyclo­penta­[b]quinolin-9-amine) was reacted with 4-methoxy­phenyl isocyanate to give the title compound, C28H30N4O4. An intra­molecular N—H⋯O hydrogen bond results in an essentially planar [r.m.s. deviation from the mean plane is 0.126 (1) Å] conformation for the biuret unit. The central ring of the quinoline unit is twisted by 78.2 (1)° with respect to the biuret mean plane, whereas the two 4-methoxy­benzene rings are twisted out of this plane by 24.3 (1)° and 48.5 (1)°, resulting in an overall propeller-like structure. An inter­molecular N—H⋯N hydrogen bond between the biuret NH atom and the quinoline ring nitro­gen defines the crystal packing. PMID:21580406

  15. Indolo[3,2-b]quinoline Derivatives Suppressed the Hemolytic Activity of Beta-Pore Forming Toxins, Aerolysin-Like Hemolysin Produced by Aeromonas sobria and Alpha-Hemolysin Produced by Staphylococcus aureus. (United States)

    Takahashi, Eizo; Fujinami, Chiaki; Kuroda, Teruo; Takeuchi, Yasuo; Miyoshi, Shin-Ichi; Arimoto, Sakae; Negishi, Tomoe; Okamoto, Keinosuke


    In an attempt to discover inhibitory compounds against pore-forming toxins, some of the major toxins produced by bacteria, we herein examined the effects of four kinds of indolo[3,2-b]quinoline derivatives on hemolysis induced by the aerolysin-like hemolysin (ALH) of Aeromonas sobria and also by the alpha-hemolysin of Staphylococcus aureus. The results showed that hemolysis induced by ALH was significantly reduced by every derivative, while that induced by alpha-hemolysis was significantly reduced by three out of the four derivatives. However, the degrees of reduction induced by these derivatives were not uniform. Each derivative exhibited its own activity to inhibit the respective hemolysin. Compounds 1 and 2, which possessed the amino group bonding the naphthalene moiety at the C-11 position of indolo[3,2-b]quinoline, had strong inhibitory effects on the activity of ALH. Compound 4 which consisted of benzofuran and quinoline had strong inhibitory effects on the activity of alpha-hemolysin. These results indicated that the amino group bonding the naphthalene moiety of compounds 1 and 2 assisted in their ability to inhibit ALH activity, while the oxygen atom at the 10 position of compound 4 strengthened its interaction with alpha-hemolysin. These compounds also suppressed the hemolytic activity of the supernatant of A. sobria or A. hydrophila, suggesting that these compounds were effective at the site of infection of these bacteria.

  16. Crystal structure of dichlorido{N1-phenyl-N4-[(quinolin-2-yl-κNmethylidene]benzene-1,4-diamine-κN4}mercury(II

    Directory of Open Access Journals (Sweden)

    Md. Serajul Haque Faizi


    Full Text Available In the mononuclear title complex, [HgCl2(C22H17N3], synthesized from the quinoline-derived Schiff base N1-phenyl-N4-[(quinolin-2-ylmethylidene]benzene-1,4-diamine (PQMBD and HgCl2, the coordination sphere around the Hg2+ atom is distorted tetrahedral, comprising two Cl atoms [Hg—Cl = 2.3487 (14 and 2.4490 (15 Å] and two N atom donors from the PQMBD ligand, viz. the quinolyl and the imine N atom [Hg—N = 2.270 (4 and 2.346 (4 Å, respectively]. The dihedral angle between the two benzene rings attached to the amino group is 43.7 (3°. In the crystal, N—H...Cl and C—H...Cl hydrogen bonds, as well as π–π stacking interactions between one phenyl ring and the pyridine ring of the quinoline moiety of an adjacent molecule [centroid-to-centroid separation = 3.617 (4 Å] are observed, resulting in a three-dimensional network.

  17. Synthesis and physical-chemical properties of 3-alkylthio-5-(quinoline-2-yl, 2-hydroxyquinoline-4-yl-4-R-2,4-dihydro-3H-1,2,4-triazoles

    Directory of Open Access Journals (Sweden)

    T. M. Kaplaushenko


    Full Text Available The major social and economic problem of pharmaceutical industry is the search for biologically active substances, which may become the basis of new drugs, competitive with expensive imported drugs. Analysis of literature shows that in recent decades the attention is paid to researches of heterocyclic systems as potential biologically active agents of both domestic and foreign scientists. Particular interest in this regard cause 3-thio derivatives of 1,2,4-triazoles. Despite high number of publications relating to synthesis and biological properties of 1,2,4-triazole derivatives, the structure and physical-chemical properties of these compounds are studied insufficiently. In this regard, the study of synthetic, physical-chemical and biological properties of 3-alkylthio-5-(quinoline-2-yl, 2-hydroxyquinoline-4-yl-4-R1-2,4-dihydro-3H-1,2,4-triazoles in our point of view is a new, theoretically and practically significant direction. Purpose - targeted synthesis of new low-toxic and highly effective compounds with potential pharmacological activity in a series of 3-alkylthio-5-(quinoline-2-yl, 2-hydroxyquinoline-4-yl-4-R-2,4-dihydro-3H-1,2,4-triazoles and the study of physical and chemical properties of the synthesized compounds. Materials and methods. As starting compounds 5-(quinoline-2-il- 2-hydroxyquinoline-4-yl-4-R1-3-thio-1,2,4-triazoles have been used. Through further cooperation with halogen alkanes (ethyl bromide, propyl bromide, amyl bromide, octyl bromide, nonyl bromide, decyl bromide, cyclohexyl chloride, benzyl chloride 3-alkylthio-5-(quinoline-2-yl, 2-hydroxyquinoline-4-yl-4-R1-2,4-dyhidro-3H-1,2,4-triazoles have been obtained. Results. 15 New compounds have been received as a result of synthetic transformations, the structure of synthesized compounds has been confirmed by modern complex of physical and chemical methods of analysis (IR-spectrophotometry, 1H NMR-spectroscopy, elemental analysis, and their individuality has been proved by

  18. VEGF receptor antagonist Cyclo-VEGI reduces inflammatory reactivity and vascular leakiness and is neuroprotective against acute excitotoxic striatal insult

    Directory of Open Access Journals (Sweden)

    McLarnon James G


    Full Text Available Abstract Background Excitotoxic brain insult is associated with extensive neuronal damage but could also cause inflammatory reactivity and vascular remodeling. The effects of the vascular endothelial growth factor (VEGF inhibitor, Cyclo-VEGI on expression of VEGF, microgliosis and astrogliosis, blood-brain barrier (BBB integrity and neuronal viability have been studied following intra-striatal injection of the excitotoxin, quinolinic acid (QUIN. The purpose of this study was to examine VEGF-dependent inflammatory responses in excitotoxin-injected brain and their dependence on pharmacological antagonism of VEGF receptors. Methods Single and double immunofluorescence staining of cellular (microglia, astrocyte, neuron responses and dye and protein infiltration of blood-brain barrier have been applied in the absence, and presence, of pharmacological modulation using a VEGF receptor antagonist, Cyclo-VEGI. Dunn-Bonferroni statistical analysis was used to measure for significance between animal groups. Results Detailed analysis, at a single time point of 1 d post-QUIN injection, showed excitotoxin-injected striatum to exhibit marked increases in microgliosis (ED1 marker, astrogliosis (GFAP marker and VEGF expression, compared with PBS injection. Single and double immunostaining demonstrated significant effects of Cyclo-VEGI treatment of QUIN-injected striatum to inhibit microgliosis (by 38%, ED1/VEGF (by 42% and VEGF striatal immunoreactivity (by 43%; astrogliosis and GFAP/VEGF were not significantly altered with Cyclo-VEGI treatment. Leakiness of BBB was indicated by infiltration of Evans blue dye and plasma protein fibrinogen into QUIN-injected striatum with barrier permeability restored by 62% (Evans blue permeability and 49% (fibrinogen permeability with Cyclo-VEGI application. QUIN-induced toxicity was demonstrated with loss of striatal neurons (NeuN marker and increased neuronal damage (Fluoro-Jade marker with significant neuroprotection

  19. Effects of methylprednisolone and 4-chloro-3-hydroxyanthranilic acid in experimental spinal cord injury in the guinea pig appear to be mediated by different and potentially complementary mechanisms. (United States)

    Yates, J R; Gay, E A; Heyes, M P; Blight, A R


    Blinded, placebo-controlled, parallel treatment group studies of the effects of methylprednisolone (MP) or 4-chloro-3-hydroxyanthranilate (4-Cl-3-HAA) on behavioral outcome and quinolinic acid tissue levels from experimental thoracic spinal cord injury in adult guinea pigs. To compare the effects of treatment with high-dose MP, a corticosteroid, and 4-Cl-3-HAA, a compound that inhibits synthesis of the neurotoxin quinolinic acid (QUIN) by activated macrophages. To explore the effect of different times of treatment using these two approaches to ameliorating secondary tissue damage. Laboratory animal studies at the University of North Carolina, Chapel Hill, NC, USA. Standardized spinal cord injuries were produced in anesthetized guinea pigs, using lateral compression of the spinal cord. Behavioral impairment and recovery were measured by placing and toe-spread responses (motor function), cutaneus trunci muscle reflex receptive field areas and somatosensory-evoked potentials (sensory function). Tissue quinolinic acid levels were measured by gas chromatograph/mass spectrometry. The current experiments showed a reduction in delayed loss of motor and sensory function in the guinea pig with MP (150 mg kg(-1), intraperitoneally in split doses between 0.5 and 6 h), but no significant reduction in tissue QUIN. Improved sensory function was seen with a single dose of 60 mg kg(-1) MP intraperitoneally at 5 h after injury, but not at 10 h after injury. A single dose of 4-Cl-3-HAA at 5 h in the guinea pig did not produce the sensory and motor improvements seen in previous studies with 12 days of dosing, beginning at 5 h. These studies, together with earlier findings, indicate that both drugs can attenuate secondary pathologic damage after SCI, but through separate mechanisms. These are most likely an acute reduction by MP of oxidative processes and reduction by 4-Cl-3-HAA of QUIN synthesis.

  20. Antitumor activity of amidino-substituted benzimidazole and benzimidazo[1,2-a]quinoline derivatives tested in 2D and 3D cell culture systems. (United States)

    Brajša, Karmen; Vujasinović, Ines; Jelić, Dubravko; Trzun, Marija; Zlatar, Ivo; Karminski-Zamola, Grace; Hranjec, Marijana


    Due to a poor clinical predictive power of 2D cell cultures, standard tool for in vitro assays in drug discovery process, there is increasing interest in developing 3D in vitro cell cultures, biologically relevant assay feasible for the development of robust preclinical anti-cancer drug screening platforms. Herein, we tested amidino-substituted benzimidazoles and benzimidazo[1,2-a]quinolines as a small platform for comparison of antitumor activity in 2D and 3D cell culture systems and correlation with structure-activity relationship. 3D cell culture method was applied on a human cancer breast (SK-BR-3, MDA-MB-231, T-47D) and pancreatic cancer cells (MIA PaCa-2, PANC-1). Results obtained in 2D and 3D models were highly comparable, but in some cases we have observed significant disagreement indicating that some prominent compounds can be discarded in early phase of researching because of compounds with false positive result. To confirm which of cell culture systems is more accurate, in vivo profiling is needed.

  1. Photophysical Characterization and in Vitro Phototoxicity Evaluation of 5,10,15,20-Tetra(quinolin-2-ylporphyrin as a Potential Sensitizer for Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Letícia D. Costa


    Full Text Available Photodynamic therapy (PDT is a selective and minimally invasive therapeutic approach, involving the combination of a light-sensitive compound, called a photosensitizer (PS, visible light and molecular oxygen. The interaction of these per se harmless agents results in the production of reactive species. This triggers a series of cellular events that culminate in the selective destruction of cancer cells, inside which the photosensitizer preferentially accumulates. The search for ideal PDT photosensitizers has been a very active field of research, with a special focus on porphyrins and porphyrin-related macrocycle molecules. The present study describes the photophysical characterization and in vitro phototoxicity evaluation of 5,10,15,20-tetra(quinolin-2-ylporphyrin (2-TQP as a potential PDT photosensitizer. Molar absorption coefficients were determined from the corresponding absorption spectrum, the fluorescence quantum yield was calculated using 5,10,15,20-tetraphenylporphyrin (TPP as a standard and the quantum yield of singlet oxygen generation was determined by direct phosphorescence measurements. Toxicity evaluations (in the presence and absence of irradiation were performed against HT29 colorectal adenocarcinoma cancer cells. The results from this preliminary study show that the hydrophobic 2-TQP fulfills several critical requirements for a good PDT photosensitizer, namely a high quantum yield of singlet oxygen generation (Φ∆ 0.62, absence of dark toxicity and significant in vitro phototoxicity for concentrations in the micromolar range.

  2. Effects of sucrose and cornstarch on 2-amino-3-methylimidazo[4,5-f]quinoline (IQ)-induced colon and liver carcinogenesis in F344 rats

    DEFF Research Database (Denmark)

    Lindecrona, R.H.; Dragsted, Lars Ove; Poulsen, Morten


    The purpose of the present study was to compare the effect of sucrose and cornstarch on colon and liver carcinogenesis induced by 0.02% of the food-borne carcinogen 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) in the feed. Male F344 rats were allocated to four groups. Two groups were fed diets...... high in either cornstarch (68%) or sucrose (34% sucrose/34% cornstarch) and were initiated with IQ. The remaining two groups received the same two diets but did not receive any IQ. In both liver and colon, administration of IQ resulted in a higher level of DNA adducts. In animals not dosed with IQ......, sucrose increased the adduct level in both organs but to a lower level than IQ. However, simultaneous administration of IQ and sucrose did not further increase the adduct level. Both IQ and sucrose increased the expression of the DNA-repair enzyme ERCC1 in the liver. In the colon, the number of large...

  3. Phase-equilibrium properties of coal-derived liquids. Technical progress report, July-December 1982. [300/sup 0/C; 40 to 1200 psia; M-cresol-quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Yesavage, V.F.; Kidnay, A.J.


    On July 1, 1980, work was initiated on a program for experimental vapor liquid equilibrium measurements on coal-derived liquids. During the last six months, effort was devoted to data collection for the m-cresol-quinoline binary system, which is a system that should be of significance in coal-derived liquid studies. Major equipment difficulties were ecnountereed with this system including continued deterioration of the seal in the back pressure regulator (which eventually had to be replaced with a different model) and continued leakage from the cell at high temperatures across the graphoil gasket. A new cell using a quartz or sapphire window and a gold seal has been designed and will be constructed shortly to replace the existing cell. In addition, analysis of the samples was hampered due to lack of reproducibility of the capillary column gas-liquid chromatograph for this system. Although our progress is less than expected, our rate of expenditure has also been low, and we hope to attain our project objectives in a longer period of time.

  4. Trichlorido{2-dimethoxymethyl-4-methyl-6-[(quinolin-8-yliminomethyl]phenolato-κ3N,N′,O1}tin(IV

    Directory of Open Access Journals (Sweden)

    Keisuke Kawamoto


    Full Text Available In the title compound, [Sn(C20H19N2O3Cl3], the SnIV ion is surrounded by a tridentate monoanionic Schiff base and by three meridional chloride ions in a six-coordinated distorted octahedral geometry. The Sn—Cl bond [2.366 (2 Å] trans to nitrogen is shorter than the others [2.438 (2 and 2.414 (2 Å]. The N—Sn—N angle [76.19 (11°] is smaller than the O—Sn—N angle [87.89 (10°] in the Schiff base ligand. No classical intermolecular hydrogen-bonding interactions are observed. The crystal packing exhibits π–π stacking interactions, with a distance of 3.595 (2 Å between the centroids of the phenolate ring and the benzene ring of the quinoline group of inversion-related molecules.

  5. Synthesis, Characterization, Antimicrobial, DNA Cleavage, and Antioxidant Studies of Some Metal Complexes Derived from Schiff Base Containing Indole and Quinoline Moieties (United States)

    Karekal, Mahendra Raj; Biradar, Vivekanand; Bennikallu Hire Mathada, Mruthyunjayaswamy


    A new Schiff base of 5-chloro-3-phenyl-1H-indole-2-carboxyhydrazide and 3-formyl-2-hydroxy-1H-quinoline (HL), and its Cu(II), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) complexes have been synthesized and characterized in the light of microanalytical, IR, H1 NMR, UV-Vis, FAB-mass, ESR, XRD, and TGA spectral studies. The magnetic susceptibility measurements and low conductivity data provide evidence for monomeric and neutral nature of the complexes. On the basis of spectral studies and analytical data, it is evident that the Schiff base acts as tridentate ligand. The Cu(II), Co(II), and Ni(II) complexes were octahedral, whereas Zn(II), Cd(II), and Hg(II) complexes were tetrahedral in nature. The redox behavior of the Cu(II) complex was investigated by electrochemical method using cyclic voltammetry. In order to evaluate the effect of metal ions upon chelation, both the ligand and its metal complexes were screened for their antibacterial and antifungal activities by minimum inhibitory concentration (MIC) method. The DNA cleavage experiment performed using agarose gel electrophoresis method showed the cleavage of DNA by all the metal complexes. The free radical scavenging activity of newly synthesized compounds has been determined at a different concentration range by means of their interaction with the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). PMID:24194692

  6. Novel Ru(II) sensitizers bearing an unsymmetrical pyridine-quinoline hybrid ligand with extended π-conjugation: synthesis and application in dye-sensitized solar cells. (United States)

    Vougioukalakis, Georgios C; Stergiopoulos, Thomas; Kontos, Athanassios G; Pefkianakis, Eleftherios K; Papadopoulos, Kyriakos; Falaras, Polycarpos


    Heteroleptic ruthenium(II) sensitizers DV42 and DV51, encompassing a novel unsymmetrical pyridine-quinoline hybrid ligand with extended π-conjugation, were synthesized, characterized, and utilized in nanocrystalline dye-sensitized solar cells. Due to the extended conjugation of DV42 and DV51, the absorption of the corresponding sensitized TiO2 films extends into the red spectral range, shifted by 30-40 nm relative to the absorption of TiO2 films sensitized with the standard Z907 ruthenium(II) dye. Contact angle measurements of DV42- and DV51-sensitized TiO2 films suggest that these films are hydrophilic with contact angle values commonly observed upon sensitization with the standard N3 ruthenium(II) dye. Electrochemical studies of the novel ruthenium(II) dyes show that their first oxidation potentials lie well below the I(-)/I3(-) redox potential allowing easy regeneration. The excited-state oxidation potentials of both dyes lie above the TiO2 conduction band, permitting efficient electron injection from the excited dye molecules into the semiconductor conduction band. Liquid electrolyte dye-sensitized solar cells incorporating DV42- or DV51-sensitized TiO2 photoelectrodes afford overall power conversion efficiencies of 3.24 or 4.36% respectively. These efficiencies are up to 56% of the power conversion efficiencies attained by TiO2 photoelectrodes sensitized by the benchmark Z907 ruthenium(II) dye under similar experimental conditions.

  7. Synthesis, DNA binding and cytotoxic activity of pyrimido[4',5':4,5]thieno(2,3-b)quinoline with 9-hydroxy-4-(3-diethylaminopropylamino) and 8-methoxy-4-(3-diethylaminopropylamino) substitutions. (United States)

    KiranKumar, Hulihalli N; RohitKumar, Heggodu G; Advirao, Gopal M


    Two new derivatives of pyrimido[4',5';4,5]thieno(2,3-b)quinoline (PTQ), 9-hydroxy-4-(3-diethylaminopropylamino)pyrimido[4',5';4,5]thieno(2,3-b)quinoline (Hydroxy-DPTQ) and 8-methoxy-4-(3-diethylaminopropylamino)pyrimido[4',5';4,5]thieno(2,3-b)quinoline (Methoxy-DPTQ) were synthesized and their DNA binding ability was analyzed using spectroscopy (UV-visible, fluorescence and circular dichroism), ethidium bromide dye displacement assay, melting temperature (T m ) analysis and computational docking studies. The hypochromism in UV-visible spectrum and increased fluorescence emission of Hydroxy-DPTQ and Methoxy-DPTQ in the presence of DNA suggested the molecule-DNA interaction. The association constants calculated from UV-visible and spectral titrations were of the order 10 4 to 10 6 M -1 . Circular dichroism studies corroborated the induced conformational changes in DNA upon addition of molecules. The change in the ellipticity was observed both in negative and positive peak of DNA, thus, suggesting the intercalation of molecules. The observed displacement of ethidium bromide from the DNA and increased T m , upon addition of DNA confirmed the intercalative mode of binding. This was further validated by computational docking, which showed clear intercalation of molecules into the d(GpC)-d(CpG) site of the receptor DNA. Anticancer activities of these molecules are evaluated by using MTT assay. Both molecules showed antiproliferative activity against all the three cancer cells studied, with Hydroxy-DPTQ being more potential molecule among the two. IC 50 value of Hydroxy-DPTQ and Methoxy-DPTQ were in the range of 3-5μM and 130-250μM, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Refined carbohydrate enhancement of aberrant crypt foci (ACF) in rat colon induced by the food-borne carcinogen 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ)

    DEFF Research Database (Denmark)

    Kristiansen, E.; Meyer, Otto A.; Thorup, I.


    ,2-dimethylhydrazine dihydrochloride (DMH) and azoxymethane (AOM), the use of a diet-related colon cancer initiator, such as the heterocyclic amine 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) formed during meat cooking, would probably give a more relevant insight into diet-related colon carcinogenesis....... In the present study it is shown that a feeding regimen with continuous low IQ doses (0.03% in the diet) throughout a study period of 10 weeks has a significant effect on the induction of ACF in the colon of male F344 rats. In addition, the study illustrates that the incidence of the IQ-induced ACF can...

  9. Twenty six-week exposure to 2 amino-3 methylimidazo [4,5-f]quinoline (IQ) does not significantly increase the incidence of tumours in HMGCR/mts1 tg579 transgenic mice

    DEFF Research Database (Denmark)

    Mortensen, Alicja; Lukanidin, E.; Ambartsumian, N.S.


    and C57BL/6ByA (wild type) mice (15 males and 15 females of each genotype per group) received either a control diet for 53 weeks or a control diet plus 0.03% 2-amino-3 methylimidazo[4,5-f]quinoline (IQ) for 26 weeks and a control diet for the remaining 27 weeks. IQ is a food mutagen with a carcinogenic...... effect in non-human primates and rodents. IQ is a liver carcinogen and also causes lung tumours and tumours of the forestomach in mice. Body weight gain and feed intake were decreased (p...

  10. N1-(Quinolin-2-ylmethyl) butane-1, 4-diamine, a polyamine analog: inhibition of platelet aggregation mediated by an elevated VASP, and decreased MAPK phosphorylation. (United States)

    Gao, Yuan; Ji, Bian-Sheng


    The current study intended to examine the signal transduction pathway of N-(quinolin-2-ylmethyl) butane-1, 4-diamine (QMA) in antiplatelet aggregation. Rats were divided randomly into five groups: control group; QMA-treated groups (0.3, 1, and 3 mg/kg); and r-Hirudin-treated group (0.3 mg/kg). Sample groups intravenously injected the corresponding agents once a day for 5 days; control group took 0.9% NaCl in the same way. Ten minutes after the last injection, blood samples were obtained from the rat abdominal aorta. Aggregation ex vivo was tested after irritating platelets by 1.5 U/ml thrombin for 5 min with a platelet aggregometer. Malondialdehyde production, activity of superoxide dismutase and nitric oxide production were determined by the microplate reader. Measurement of [Ca]i was performed using a fluorescence spectrophotometer. Thromboxane A2, cyclic adenosine monophosphate and cyclic guanosine monophosphate levels, vasodilator-stimulated phosphoprotein, and mitogen-activated protein kinase phosphorylation were measured with ELISA kits. Phospholipase C γ2 and protein kinase C were observed by immunoblotting study. QMA inhibited thrombin-induced platelet aggregation ex vivo. QMA significantly elevated superoxide dismutase activity, levels of cyclic adenosine monophosphate, cyclic guanosine monophosphate, nitric oxide, and subsequently promoted vasodilator-stimulated phosphoprotein phosphorylation. Meanwhile, QMA suppressed phospholipase C γ2, protein kinase C and mitogen-activated protein kinase phosphorylation, as well as malondialdehyde, thromboxane A2 formation and [Ca]i mobilization. QMA has a strong antiplatelet potential via its multitarget mechanism.

  11. Preparation of pillar[5]arene-quinoline Langmuir-Blodgett thin films for detection of volatile organic compounds with host-guest principles. (United States)

    Kursunlu, Ahmed Nuri; Acikbas, Yaser; Ozmen, Mustafa; Erdogan, Matem; Capan, Rifat


    In this study, a novel pillar[5]arene-quinoline (P5-Q) as an organic material is used to fabricate Langmuir-Blodgett (LB) thin films and its organic vapor sensing properties have been investigated. The LB deposition process is characterized by UV-visible spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM) and quartz crystal microbalance (QCM) techniques. The typical frequency shift per layer is obtained as 31.75 Hz per layer and the deposited mass onto a quartz crystal is calculated to be 539.69 ng per layer (2.03 ng mm -2 ). The fitted surface plasmon resonance (SPR) data were utilized to calculate the film thickness of this material. The thickness of a single layer is calculated to be 1.26 ± 0.09 nm. QCM and SPR systems are used to investigate gas sensing performance of macrocyclic LB films during exposure to Volatile Organic Compounds (VOCs). The macrocyclic LB thin films are more sensitive to dichloromethane than that of other vapors used in this study. The sensitivity and detection limit performance of the P5-Q QCM sensor to dichloromethane vapor were calculated to be 14.751 Hz ppm -1 and 0.203 ppm, respectively. These results demonstrated that the P5-Q material is promising as an organic vapor sensing device at room temperature. Despite Langmuir-Blodgett being a traditional technique in colloid and interface science, this study presents the first gas sensor application for pillararene LB films. Because of the unique symmetric pillar architecture of P5-Q, self-assembly of pillar[5]arene molecules should afford various characteristic nanometer-scale architectures such as micelles, vesicles, and tubes.

  12. Benzimidazole derivatives related to 2,3-acrylonitriles, benzimidazo[1,2-a]quinolines and fluorenes: synthesis, antitumor evaluation in vitro and crystal structure determination. (United States)

    Hranjec, Marijana; Pavlović, Gordana; Marjanović, Marko; Kralj, Marijeta; Karminski-Zamola, Grace


    A synthesis and biological evaluation of new benzimidazole derivatives, related to 2,3-disubstituted acrylonitriles, benzimidazo[1,2-a]quinoline-6-carbonitriles and heteroaromatic fluorenes was described. The molecular and crystal structures of three compounds 4, 16 and 17 reveal that non-fused fluoro derivative, 4, deviates from planarity by 13.11(2) degrees, while fused methyl, 16, and fluoro, 17, derivatives are planar within 4 degrees exhibiting a planar aromatic surface capable to intercalate into double-stranded DNA. Compound 4 exists as E-isomer. The crystal structures confirmed that hydrogen bonding patterns are characterized dominantly by the weak C-H...N(F) bonds, except in the case of 4 where the presence of ethanol molecule of crystallization resulted in the N-H...O and O-H...N hydrogen bonds formation. In the crystal structures of 16 and 17 cyano group participates in hydrogen bonding formation, while in 4 this is not the case. All compounds, except 16 and 14 exerted pronounced antiproliferative activity on five tumor cell lines, whereby 2-benzimidazolyl-3-N-methylpyrolyl-acrylonitrile 13 and its fused analogue 23 exerted the highest activity on all cell lines (IC50=0.8-30 microM) and showed a special selectivity toward HeLa cells. There is no major difference in the biological activity between non-fused and fused analogues. Similarly, all compounds showed significant interaction with ct-DNA, supporting the fact that their antitumor activity could partially be the consequence of DNA-binding. The cyano moiety is important for the activity, but not the selectivity of tested compounds. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  13. Molecular evolution of the nicotinic acid requirement within the Shigella/EIEC pathotype. (United States)

    Di Martino, Maria Letizia; Fioravanti, Rosa; Barbabella, Giada; Prosseda, Gianni; Colonna, Bianca; Casalino, Mariassunta


    Nicotinamide adenine dinucleotide (NAD) is a crucial cofactor in several anabolic and catabolic reactions. NAD derives from quinolinic acid (QUIN) which in Escherichia coli is obtained through a pyridine salvage pathway or a de novo synthesis pathway. In the latter case, two enzymes, L-aspartate oxidase (NadB) and quinolinate synthase (NadA), are required for the synthesis of QUIN. In contrast to its E. coli ancestor, Shigella spp., the causative agent of bacillary dissentery, lacks the de novo pathway and strictly requires nicotinic acid for growth (Nic⁻ phenotype). This phenotype depends on the silencing of the nadB and nadA genes and its pathoadaptive nature is suggested by the observation that QUIN attenuates the Shigella invasive process. Shigella shares the pathogenicity mechanism with enteronvasive E. coli (EIEC), a group of pathogenic E. coli. On the basis of this similarity EIEC and Shigella have been grouped into a single E. coli pathotype. However EIEC strains do not constitute a homogeneous group and do not possess the complete set of characters that define Shigella strains. In this work we have analysed thirteen EIEC strains belonging to different serotypes and originating from different geographic areas. We show that, in contrast to Shigella, only some EIEC strains require nicotinic acid for growth in minimal medium. Moreover, by studying the emergence of the Nic⁻ phenotype in all serotypes of S. flexneri, as well as in S. sonnei and S. dysenteriae, we describe which molecular rearrangements occurred and which mutations are responsible for the inactivation of the nadA and nadB genes. Our data confirm that the genome of Shigella is extremely dynamic and support the hypothesis that EIEC might reflect an earlier stage of the pathoadaptation process undergone by Shigella. Copyright © 2013. Published by Elsevier GmbH.

  14. FT-IR, FT-Raman and NMR characterization of 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate and investigation of its reactive and optoelectronic properties by molecular dynamics simulations and DFT calculations (United States)

    Menon, Vidya V.; Fazal, Edakot; Mary, Y. Sheena; Panicker, C. Yohannan; Armaković, Stevan; Armaković, Sanja J.; Nagarajan, Subban; Van Alsenoy, C.


    The FT-IR and FT-Raman spectra of the synthesized compound, 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate is recorded and analyzed. Optimized molecular structure, wave numbers, corresponding assignments regarding 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate has become screened tentatively as well as hypothetically using Gaussian09 program package. Natural bonding orbital assessment has been completed with a reason to clarify charge transfer or conjugative interaction, the intra-molecular re-hybridization and delocalization of electron density within the molecule. The NMR spectral assessment had been made choosing structure property relationship by chemical shifts along with the magnetic shielding effects regarding the title compound. The first and second hyperpolarizabilities were calculated. The calculated first order hyperpolarizability is commensurate with the documented worth of very similar derivatives and could be an interesting object for more experiments on nonlinear optics. Local reactivity properties have been investigated using average local ionization energies and Fukui functions. Investigation of optoelectronic properties encompassed calculations of reorganization energies and hopping rates of charge carriers within the framework of Marcus semi-empiric approach. The docked ligand title compound forms a stable complex with CDK inhibitors and gives a binding affinity value of -9.7 kcal/mol and molecular docking results suggest that the compound might exhibit inhibitory activity against CDK inhibitors.

  15. Synthesis, biological assessment and molecular modeling of 14-aryl-10,11,12,14-tetrahydro-9H-benzo[5,6]chromeno[2,3-b]quinolin-13-amines. (United States)

    Maalej, Emna; Chabchoub, Fakher; Samadi, Abdelouahid; de los Ríos, Cristóbal; Perona, Almudena; Morreale, Antonio; Marco-Contelles, José


    The synthesis and pharmacological evaluation of racemic 14-aryl-10,11,12,14-tetrahydro-9H-benzo[5,6]chromeno[2,3-b]quinolin-13-amines (19-28), prepared by Friedländer reaction of 3-amino-1-aryl-1H-benzo[f]chromene-2-carbonitriles (10-18) with suitable cycloalkanones is described. These molecules are potent, in the nanomolar range [IC(50) (EeAChE)=7-101 nM], and selective inhibitors of acetylcholinesterase (AChE). The most potent inhibitor, 4-(13-amino-10,11,12,14-tetrahydro-9H-benzo[5,6]chromeno[2,3-b]quinolin-14-yl)phenol (20) [IC(50) (EeAChE)=7±2 nM] is four-fold more active than tacrine. Kinetic studies on compound 20 showed that this is a mixed-type inhibitor of EeAChE with a K(i) of 5.00 nM. However, racemic 20 was unable to displace propidium iodide, suggesting that the inhibitor does not strongly bind to the peripheral anionic site (PAS) of AChE. Docking, molecular dynamics stimulations, and MM-GBSA calculations agree well with this behavior. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Spectroscopic (FT-IR, (1)H, (13)C NMR and UV-vis) characterization and DFT studies of novel 8-((4-(methylthio)-2,5-diphenylfuran-3-yl)methoxy)quinoline. (United States)

    Diwaker; Chidan Kumar, C S; Kumar, Ashwani; Chandraju, Siddegowda


    In this study, computational calculations of a new quinoline derivative: 8-((4-(methylthio)-2,5-diphenylfuran-3-yl)methoxy)quinoline is carried out using ab initio methods. The geometry optimization as well as fundamental frequencies of the most stable configuration of the title compound is reported. A detailed study of Infrared spectrum, chemical shifts and electronic spectrum of the title compound is also presented. The Gauge-Invariant Atomic Orbital approach is used to calculate the proton and carbon chemical shifts of the title compound. The natural bond orbital analysis of the title compound is also reported in order to understand the stability of the molecule which arises from hyper conjugative interactions and charge delocalization. The theoretical electronic absorption spectrum is also reported using the time dependent density functional approach. The molecular structure along with vibrational frequencies as simulated for binding of iron with the title compound is also reported using ab initio methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Tunable AIEE fluorescence constructed from a triphenylamine luminogen containing quinoline - application in a reversible and tunable pH sensor. (United States)

    Zhang, Mengmeng; Yang, Wen; Gong, Tingfeng; Zhou, Weiqun; Xue, Renyu


    Herein, tunable emissions in aggregation processes of triphenylamine derivatives (TPAQs) and their protonated cations, as well as protonated processes have been described. In this study, three triphenylamine-based compounds (TPAQs) were synthesized and their optical properties were investigated. Initially, the TPAQs displayed aggregation-induced emission enhancement (AIEE) properties via the restricted intramolecular charge transfer (ICT) state. Interestingly, the single-branched fluorophore (STPAQ) and its protonated cation emitted different color fluorescence in the solution and aggregation state. They emitted green fluorescence, which originated from the intramolecular charge transfer (ICT) state in a strong polar solvent, but the fluorescence bands turned blue, which was attributed to the LE state in the aggregated state. However, the cations of triple-branched fluorophores (TTPAQs) exhibited an inverse tunable emission process from bluish violet fluorescence of the LE state in a weak polar solvent (e.g., THF) to green fluorescence of the ICT state in the aggregated state. In a THF/water mixture solution (fw = 10%), the STPAQ could switch its emission between blue and green in the pH range of 10.0-0.5. This phenomenon enabled STPAQ to serve as a fluorescent pH sensor in solution. In the powder state, double-branched fluorophores (DTPAQs) could be used as a fluorescent sensor for the detection of acidic and basic organic vapors in the solid state.

  18. The β2-adrenoceptor agonist clenbuterol elicits neuroprotective, anti-inflammatory and neurotrophic actions in the kainic acid model of excitotoxicity. (United States)

    Gleeson, Lorna C; Ryan, Katie J; Griffin, Eadaoin W; Connor, Thomas J; Harkin, Andrew


    Excitotoxicity is a mechanism of neuronal cell death implicated in a range of neurodegenerative conditions. Systemic administration of the excitotoxin kainic acid (KA) induces inflammation and apoptosis in the hippocampus, resulting in neuronal loss. Evidence indicates that stimulation of glial β(2)-adrenoceptors has anti-inflammatory and neurotrophic properties that could result in neuroprotection. Consequently, in this study we examined the effect of the β(2)-adrenoceptor agonist clenbuterol on KA-induced inflammation, neurotrophic factor expression and apoptosis in the hippocampus. Clenbuterol (0.5mg/kg) was administered to rats one hour prior to KA (10mg/kg). Epileptic behaviour induced by KA was assessed for three hours following administration using the Racine scale. Twenty-four hours later TUNEL staining in the CA3 hippocampal subfield and hippocampal caspase-3 activity was assessed to measure KA-induced apoptosis. In addition, expression of inflammatory cytokines (IL-1β and IFN-γ), inducible nitric oxide synthase (iNOS), kynurenine pathway enzymes indolamine 2,3-dioxygenase (IDO) and kynurenine monooxygenase (KMO), the microglial activation marker CD11b, and the neurotrophins BDNF and NGF were quantified in the hippocampus using real-time PCR. Whilst clenbuterol treatment did not significantly alter KA-induced epileptic behavior it ameliorated KA-induced apoptosis, and this neuroprotective effect was accompanied by reduced inflammatory cytokine expression, reduced expression of iNOS, IDO, KMO and CD11b, coupled with increased BDNF and NGF expression in KA-treated rats. In conclusion, the β(2)-adrenoceptor agonist clenbuterol has anti-inflammatory and neurotrophic actions and elicits a neuroprotective effect in the KA model of neurodegeneration. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Effect of Mentha pulegium extract and 8-hydroxy quinoline sulphate to extend the quality and vase life of rose (Rosa hybrid) cut flower. (United States)

    Hashemabadi, Davood; Torkashvand, Ali Mohammadi; Kaviani, Behzad; Bagherzadeh, Maryam; Rezaalipour, Mohaddeseh; Zarchini, Mohammad


    Rose is an ornamental plant which contains one of the world's top cut flowers. Vase life of cut rose flower is short. Extracts of Mentha pulegium and 8-hydroxy quinoline sulphate (8-HQS) were used as two preservative solutions, aiming to extend the vase life of cut rose (Rosa hybrid L.) flowers. Rose flowers were treated with a vase solution containing the extract of M. pulegium, at concentrations of 0, 10, 20 and 30%, in combination with 8-HQS at concentrations of 0, 200, 400 and 600 mg l(-1). Longevity of cut roses flowers was determined on the basis of wilting and chlorophyll retention. Cut roses flowers were kept at room temperature (20 ± 2 degrees C) under normal day light and natural ventilation. The vase life of cut flowers studied was prolonged by all 8-HQS and extract treatments. The best concentration of 8-HQS and extractwere 400 mg l(-1) and 10%, respectively. Our results indicated that the flowers treated with the extract and 8-HQS had longer vase life, higher rate of solution uptake and lower SPAD value (total chlorophyll) compared to the control. Also, cut flowers treated with the extract and 8-HQS had least bacterial colonies. The greatest longevity of vase life by 11.20 and 10.25 days was related to 400 mg I(-1) 8-HQS and 10% of extract, respectively. These treatments improved cut vase life more than the control treatment. The maximum solution uptake (1.85 ml g(-1) f.wt.) and minimum SPAD value (2.19) were calculated in 30% extract along with 200 mg l(-1) 8-HQS, and 200 mg l(-1) 8-HQS, respectively. The lowest number of bacterial colonies (55.75) was obtained in treatment of 600 mg l(-1) 8-HQS. Flower quality of specimens treated with extract and 8-HQS was better than those of the control. The experiments were repeated three times with three replicates and a completely randomized design had been used. The present study concludes that it would be possible to use preservative solutions containing extract of M. pulegium L. and 8-HQS to extend vase

  20. Structure-activity relationships of highly cytotoxic copper(II) complexes with modified indolo[3,2-c]quinoline ligands. (United States)

    Primik, Michael F; Göschl, Simone; Jakupec, Michael A; Roller, Alexander; Keppler, Bernhard K; Arion, Vladimir B


    A number of indolo[3,2-c]quinolines were synthesized and modified at the lactam unit to provide a peripheral binding site able to accommodate metal ions. Potentially tridentate ligands HL(1a)-HL(4a) and HL(1b)-HL(4b) were reacted with copper(II) chloride in isopropanol/methanol to give novel five-coordinate copper(II) complexes [Cu(HL(1a-4a))Cl(2)] and [Cu(HL(1b-4b))Cl(2)]. In addition, a new complex [Cu(HL(5b))Cl(2)] and two previously reported compounds [Cu(HL(6a))Cl(2)] and [Cu(HL(6b))Cl(2)] with modified paullone ligands HL(5b), HL(6a), and HL(6b), which can be regarded as close analogues of indoloquinolines HL(1b), HL(4a), and HL(4b), in which the pyridine ring was formally substituted by a seven-membered azepine ring, were synthesized for comparison. The new ligands and copper(II) complexes were characterized by (1)H and (13)C NMR, IR and electronic absorption spectroscopy, ESI mass spectrometry, magnetic susceptibility measurements in solution at 298 K ([Cu(HL(1a))Cl(2)] and [Cu(HL(4b))Cl(2)]), and X-ray crystallography ([Cu(HL(3b))Cl(2)]·3DMF, [Cu(HL(4b))Cl(2)]·2.4DMF, HL(5b) and [Cu(HL(5b))Cl(2)]·0.5CH(3)OH). All complexes were tested for cytotoxicity in the human cancer cell lines CH1 (ovarian carcinoma), A549 (non-small cell lung cancer), and SW480 (colon carcinoma). The compounds are highly cytotoxic, with IC(50) values ranging from nanomolar to very low micromolar concentrations. Substitution of the seven-membered azepine ring in paullones by a pyridine ring resulted in a six- to nine-fold increase of cytotoxicity in SW480 cells. Electron-releasing or electron-withdrawing substituents in position 8 of the indoloquinoline backbone do not exert any effect on cytotoxicity of copper(II) complexes, whereas copper(II) compounds with Schiff bases obtained from 2-acetylpyridine and indoloquinoline hydrazines are 10 to 50 times more cytotoxic than those with ligands prepared from 2-formylpyridine and indoloquinoline hydrazines.

  1. [Synthesis and spectral properties of polymer of Tis (5, 5'-methylene-bis (8-hydroxy-quinoline) gallium with orange-red light emitting]. (United States)

    Guo, Hai-bo; Hao, Yu-ying; Fan, Wen-hao; Zhang, Zhi-qiang; Guo, Xiao-xia; Xu, Bing-she


    A ligand 5,5'-methylene-bis(8-hydroxyquinoline)(Hqq) was synthesized by condensation reaction at low temperature and was subsequently coordinated to gallium ions to prepare the polymer of tis(5,5'-methylene-bis(8-hydroxyquinoline) gallium (Gaqq3)n. Both chemical structure and phase structure of the ligand and complexes were characterized by Infrared absorption spectrum and X-ray diffraction (XRD). The thermal stability of the complexes was studied by thermogravimetry (TG). The photo-physical properties of the complexes were investigated by ultraviolet absorption spectrum (UV), fluorescence excitation spectrum and emission spectrum. The result indicated that (Gaqq3)n is a thermally stable material, whose decomposition temperature is 443.6 degrees C. The ultraviolet absorption bands of (Gaqq3)n are in the range of 250-500 nm, with a relatively strong band tail absorption between 500 and 650 nm, which shows that the band-gap defect states exists in the forbidden band. The fluorescence excitation band of (Gaqq3)n is located at 380-456 nm, and (Gaqq3)n. emits orange-red fluorescence with the emission peak at 568 nm, which shows that the fluorescence emission of (Gaqq3), is mainly attributed to the charge transfer transitions from phenol to ring pyridine ring, while the pi-->pi* transition of benzene ring is deactivated by non-radiative transition, and makes no contribution to fluorescence emission. (Gaqq3)n optical band gap is 2.49 eV. Compared with the fluorescence emission peak of Gaq3, the fluorescence intensity of (Gaqq3), decreases, which is attributed to the distortion of the two quinoline rings connected to the methylene, hence leads to the poor rigidity and coplanarity of (Gaqq3)n, thus affects fluorescence emission intensity. Because of the extending of the molecular conjugation system, pi electron of (Gaqq3)n is more delocalized, resulting in the redshift of fluorescence emission peak (Gaqq3)n is expected to be applied in organic light emitting display and

  2. Ciliary neurotrophic factor protects striatal neurons against excitotoxicity by enhancing glial glutamate uptake.

    Directory of Open Access Journals (Sweden)

    Corinne Beurrier

    Full Text Available Ciliary neurotrophic factor (CNTF is a potent neuroprotective cytokine in different animal models of glutamate-induced excitotoxicity, although its action mechanisms are still poorly characterized. We tested the hypothesis that an increased function of glial glutamate transporters (GTs could underlie CNTF-mediated neuroprotection. We show that neuronal loss induced by in vivo striatal injection of the excitotoxin quinolinic acid (QA was significantly reduced (by approximately 75% in CNTF-treated animals. In striatal slices, acute QA application dramatically inhibited corticostriatal field potentials (FPs, whose recovery was significantly higher in CNTF rats compared to controls (approximately 40% vs. approximately 7%, confirming an enhanced resistance to excitotoxicity. The GT inhibitor DL-threo-beta-benzyloxyaspartate greatly reduced FP recovery in CNTF rats, supporting the role of GT in CNTF-mediated neuroprotection. Whole-cell patch-clamp recordings from striatal medium spiny neurons showed no alteration of basic properties of striatal glutamatergic transmission in CNTF animals, but the increased effect of a low-affinity competitive glutamate receptor antagonist (gamma-D-glutamylglycine also suggested an enhanced GT function. These data strongly support our hypothesis that CNTF is neuroprotective via an increased function of glial GTs, and further confirms the therapeutic potential of CNTF for the clinical treatment of progressive neurodegenerative diseases involving glutamate overflow.

  3. IND-2, a pyrimido[1″,2″:1,5]pyrazolo[3,4-b]quinoline derivative, circumvents multi-drug resistance and causes apoptosis in colon cancer cells. (United States)

    Karthikeyan, Chandrabose; Lee, Crystal; Moore, Joshua; Mittal, Roopali; Suswam, Esther A; Abbott, Kodye L; Pondugula, Satyanarayana R; Manne, Upender; Narayanan, Narayanan K; Trivedi, Piyush; Tiwari, Amit K


    Naturally occurring condensed quinolines have anticancer properties. In efforts to find active analogues, we designed and synthesized eight polycyclic heterocycles with a pyrimido[1″,2″:1,5]pyrazolo[3,4-b]quinoline framework (IND series). The compounds were evaluated for activity against colon (HCT-116 and S1-MI-80), prostate (PC3 and DU-145), breast (MCF-7 and MDAMB-231), ovarian (ov2008 and A2780), and hepatocellular (HepG2) cancer cells and against non-cancerous Madin Darby canine kidney (MDCK), mouse embryonic fibroblast (NIH/3T3), and human embryonic kidney cells (HEK293). IND-2, a 4-chloro-2-methyl pyrimido[1″,2″:1,5]pyrazolo[3,4-b]quinoline, exhibited more than ten-fold selectivity and potent cytotoxic activity against colon cancer cells relative to the other cancer and non-cancer cells. With five additional colon cancer cell lines (HT-29, HCT-15, LS-180, LS-174, and LoVo), IND-2 had similar cytotoxicity and selectivity, and sub-micromolar concentrations caused changes in the morphology of HCT-116 and HCT-15 cells. IND-2 did not activate the transactivating function of the pregnane X receptor (PXR), indicating that it does not induce PXR-regulated ABCB1 or ABCG2 transporters. Indeed, IND-2 was not a substrate of ABCB1 or ABCG2, and it induced cytotoxicity in HEK293 cells overexpressing ABCB1 or ABCG2 to the same extent as in normal HEK293 cells. IND-2 was cytotoxic to resistant colon carcinoma S1-MI-80 cells, approximately three- and five-fold more than SN-38 and topotecan, respectively. In HCT-116 colon cancer cells, IND-2 produced concentration-dependent changes in mitochondrial membrane potential, leading to apoptosis, and sub-micromolar concentrations caused chromosomal DNA fragmentation. These findings suggest that, by increasing apoptosis, IND-2 has potential therapeutic efficacy for colorectal cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Pharmacological characterisation of acid-induced muscle allodynia in rats. (United States)

    Nielsen, Alexander Norup; Mathiesen, Claus; Blackburn-Munro, Gordon


    Previous studies have shown that repeated injections of acidic saline, given into the lateral gastrocnemius muscle of rats, results in a bilateral reduction in withdrawal threshold to tactile stimulation of the hindpaws. We have now characterised this model of muscoskeletal pain pharmacologically, by evaluating the antinociceptive effects of various analgesics after systemic administration. The micro-opioid receptor agonist morphine (3 and 6 mg/kg) produced a particularly prolonged antiallodynic effect. The glutamate receptor antagonists ([8-methyl-5-(4-(N,N-dimethylsulfamoyl)phenyl)-6,7,8,9,-tetrahydro-1H-pyrrolo[3,2-h]-iso-quinoline-2,3-dione-3-O-(4-hydroxybutyric acid-2-yl)oxime] NS1209 and ketamine (6 and 15 mg/kg, respectively), the KCNQ K(+) channel openers retigabine and flupirtine (10 and 20 mg/kg, respectively) and the Na(+) channel blocker mexiletine (37.5 mg/kg) also significantly increased paw withdrawal threshold, although to a lesser degree than morphine. In contrast, the anticonvulsant lamotrigine (30 mg/kg), the cyclooxygenase-2 inhibitor carprofen (15 mg/kg) and the benzodiazepine diazepam (3 mg/kg) were ineffective. All antinociceptive effects were observed at nonataxic doses as determined by the rotarod test. These results suggest that in this model, muscle-mediated pain can be alleviated by various analgesics with differing mechanisms of action, and that once established ongoing inflammation does not appear to contribute to this process.

  5. Preparation and characterization of ZrO2 supported Fe3O4 MNPs as an effective and reusable superparamagnetic catalyst for the riedländer synthesis of quinoline derivatives

    Directory of Open Access Journals (Sweden)

    Hejazi Seyyedeh Zoha


    Full Text Available In this study, a convenient, appropriate and eco-friendly method for the synthesis of quinoline derivatives via Friedländer reaction has been developed by using ZrO2/Fe3O4-MNPs as an effective and reusable heterogeneous catalyst. The morphology of ZrO2/Fe3O4-MNPs has been studied by XRD, FT-IR, SEM, TEM and VSM techniques. Green procedure, straight and easy work-up, high yields of the products and good reaction times are the benefits of this procedure. Further, the catalyst can be recovered by external magnetic field and reused at least for three times without a considerable decrease in its catalytic activity.

  6. Mutagenicity of 2-amino-3-methylimidazo[4,5-f]quinoline in colon and liver of Big Blue rats: role of DNA adducts, strand breaks, DNA repair and oxidative stress

    DEFF Research Database (Denmark)

    Moller, P.; Wallin, H.; Vogel, U.


    weeks. There were dose-response relationships of DNA adducts (P-32-postlabeling) and DNA strand breaks (comet assay) in colon and liver tissues, with the highest levels of DNA adducts and strand breaks in the colon. There was dose-dependent induction of mutations in both the colon and the liver...... and colon. A lower frequency of mutations in the colon than in the liver could be related to higher expression of DNA repair enzymes in the former.......The contribution of oxidative stress, different types of DNA damage and expression of DNA repair enzymes in colon and liver mutagenesis induced by 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) was investigated in four groups of six Big Blue rats fed diets with 0, 20, 70, and 200 mg IQ/kg for 3...

  7. Effects of dietary antioxidants and 2-amino-3-methylimidazo[4,5-f]-quinoline (IQ) on preneoplastic lesions and on oxidative damage, hormonal status, and detoxification capacity in the rat

    DEFF Research Database (Denmark)

    Breinholt, Vibeke M.; Mølck, Anne-Marie; Svendsen, Gitte Winkel


    mechanisms were assayed in blood, liver and colon and the impact of the antioxidant administrations on putative preneoplastic changes in liver and colon was assessed. The dietary carcinogen, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) (200 mg/kg diet) served as a pro-oxidant, genotoxicity and general...... toxicity control. IQ increased the levels of protein and DNA oxidation products in plasma, the area of glutathione S-transferase-placental form positive (GST-P) foci in the liver as well as the number of colonic aberrant crypt foci (ACF). All antioxidants and the antioxidant combination significantly...... increased the level of lymphocytic DNA damage, to an extent comparable with the effect induced by IQ. In contrast to the control group where no GST-P foci were detected, GST-P foci were detected in animals exposed to quercetin, lycopene and the combination of the two. However, the increase in the volume...

  8. Magnetite Nanoparticles-Supported APTES as a Powerful and Recoverable Nanocatalyst for the Preparation of 2-Amino-5,10-dihydro- 5,10-dioxo-4H-benzo[g]chromenes and Tetrahydrobenzo[g]quinoline-5,10- diones. (United States)

    Ghasemzadeh, Mohammad Ali; Elyasi, Zahra; Azimi-Nasrabad, Mina; Mirhosseini-Eshkevari, Boshra


    This study introduces a green and effective approach for the preparation of biologically-active heterocyclic compounds including 2-amino-5,10-dihydro-5,10-dioxo-4Hbenzo[ g]chromenes and tetrahydrobenzo[g]quinoline-5,10-diones using one-pot multi-component reactions in the presence of Fe3O4@SiO2-NH2 nanocomposite. The preparation and use of aminofunctionalized Fe3O4@SiO2 as a powerful and reusable nanocatalyst is described. The catalyst was characterized by spectral techniques including FT-IR, SEM, XRD, EDX and VSM analysis. This method offers the advantages of high yields, short reaction times, comfortable work-up and reusability of the catalyst. The amino-functionalization silica-coated magnetite nanocomposite was prepared by three step method and the structure elucidation of the nanocatalyst has been done using various spectroscopic analyses. Then, the Fe3O4@SiO2-NH2 nanocomposite was used in the multicomponent synthesis of 2-amino-5,10-dihydro-5,10-dioxo-4H-benzo[g]chromenes and tetrahydrobenzo[g]quinoline-5,10-diones under reflux conditions. All of the products were analyzed with m.p., 1H NMR, 13C NMR and FT-IR spectroscopy techniques. The study on the recoverability of the nanocatalyst showed the recovered Fe3O4@SiO2-NH2 nanocomposite could be reused sixth consecutive times with a little-decreased activity. Amino-functionalized SiO2 coated Fe3O4 nanocomposite exhibited superparamagnetic behavior and strong magnetization at room temperature. The average crystallite sizes of the catalyst was about 50-60 nm. The obtained magnetic nanocomposite showed excellent catalytic activity as a new heterogeneous magnetic catalyst for the synthesis of some benzo[g]chromenes and tetrahydrobenzo[g]quinoline-5,10-diones. We propose that NH2 groups on the surfaces of nanocomposite act as the Brønsted base and cause to dehydrogenation of substrates to promote the reactions. It was found that Fe3O4@SiO2-NH2 nanocomposite act as an eco-friendly and efficient catalyst for one

  9. Synthesis, characterization, antimicrobial, DNA-cleavage and antioxidant activities of 3-((5-chloro-2-phenyl-1H-indol-3-ylimino)methyl)quinoline-2(1H)-thione and its metal complexes (United States)

    Vivekanand, B.; Mahendra Raj, K.; Mruthyunjayaswamy, B. H. M.


    Schiff base 3-((5-chloro-2-phenyl-1H-indol-3-ylimino)methyl)quinoline-2(1H)-thione and its Cu(II), Co(II), Ni(II), Zn(II) and Fe(III), complexes have been synthesized and characterized by elemental analysis, UV-Visible, IR, 1H NMR, 13C NMR and mass spectra, molar conductance, magnetic susceptibility, ESR and TGA data. The ligand and its metal complexes have been screened for their antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, antifungal activity against Aspergillus niger and Aspergillus flavus in minimum inhibition concentration (MIC) by cup plate method respectively, antioxidant activity using 1,1-diphenyl-2-picryl hydrazyl (DPPH), which was compared with that of standard drugs vitamin-C and vitamin-E and DNA cleavage activity using calf-thymus DNA.

  10. 1-Benzoyl-3-[3-cyano-8-methyl-4-(1-methyl-1H-pyrrol-2-yl)-5,6,7,8-tetra­hydro­quinolin-2-yl]thio­urea (United States)

    Asiri, Abdullah M.; Faidallah, Hassan M.; Al-Youbi, Abdulrahman O.; Alamry, Khalid A.; Ng, Seik Weng


    In the N-substituted benzoyl­thio­urea, C24H23N5OS, the benzoyl­thio­urea unit is non-planar (r.m.s. deviation = 0.126 Å). The aliphatic part of the tetra­hydro­quinoline fused-ring system is disordered over two positions in a 0.592 (5):0.408 (5) ratio. The pyridine and pyrrole rings are twisted by 55.2 (1)° in order to avoid crowding of their respective substituents. Pairs of mol­ecules are linked by N—H⋯N hydrogen bonds, forming centrosymmetric dimers. Furthermore, an intra­molecular N—H⋯O hydrogen bond stabilizes the mol­ecular conformation. PMID:22064903

  11. Synthesis, Characterization and Biological Evaluation of Mononuclear Dichloro-bis[2-(2-chloro-6,7-substituted Quinolin-3-yl-1H-benzo[d]imidazole]Co(II Complexes

    Directory of Open Access Journals (Sweden)

    Minaxi Samatbhai Maru


    Full Text Available A series of Co(II complexes 3¢a-g of 2-(2-chloro-6,7-substituted quinolin-3-yl-1H-benzo[d]imidazole ligands 3a-g were prepared and characterized by various spectroscopic and physico-chemical methods viz. FT-IR, ESI mass, 1H NMR, 13C NMR and UV-Visible spectroscopy, Thermogravimetric analysis, Magnetic susceptibility, Molar conductance and Elemental analysis. The 2-(2-chloro-6,7-substituted quinolin-3-yl-1H-benzo[d]imidazole ligands 3a-g have been synthesized by cyclocondensation of benzene-1,2-diamine with 2-chloroquinoline-3-carbaldehydes by using ceric ammonium nitrate as a catalyst in presence of hydrogen peroxide as an oxidant. The structures of all ligands were confirmed by IR, Mass, UV-Visible, 1H NMR and 13C NMR spectroscopy. All ligands 3a-g and their Co(II complexes 3¢a-g were screened for their in vitro antimicrobial activity using twofold serial dilution technique against standard MTCC strains of two Gram-positive Staphylococcus aureus and Streptococcus pyogenes, two Gram-negative Escherichia coli and Pseudomonas aeruginosa bacteria and three Candida albicans, Aspergillus niger and Aspergillus clavatus fungus in comparison with standard drugs. All ligands 3a-g and complexes 3¢a-g also evaluated for antimycobacterial activity against standard Mycobacterium tuberculosis H37Rv strain. DOI:

  12. Prebiotics and age, but not probiotics affect the transformation of 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ) by fecal microbiota - An in vitro study. (United States)

    Nowak, Adriana; Czyżowska, Agata; Huben, Krzysztof; Sójka, Michał; Kuberski, Sławomir; Otlewska, Anna; Śliżewska, Katarzyna


    Heterocyclic aromatic amines (HAAs) are carcinogens which are formed in meat cooked using high-temperature methods. The human gastrointestinal (GI) microbiota plays a crucial role in maintaining health in humans of different ages, and especially in the elderly. However, the GI microbiota, whose metabolism and composition changes with age, may also be responsible for the activation of mutagenic substances reaching the colon with diet. Probiotics and prebiotics are promising in terms of reducing the destructive effects of HAAs. The aim of the study was to determine if fecal microbiota derived from the feces of 27 volunteers: infants (up to 18 months), adults (aged 23-39 years), the sub-elderly (aged 64-65 years), and the elderly (aged 76-87 years), and the presence of probiotics or prebiotics, affected the transformation of IQ (2-amino-3-methylimidazo[4,5-f]quinoline) to 7-OH-IQ (2-amino-3,6-dihydro-3-methyl-7H-imidazo[4,5-f]quinoline-7-one). The compounds were identified using LC-MS(n), NMR, and FTIR. Their genotoxicity was compared in the comet assay. Individual strains capable of IQ transformation were also identified. 7-OH-IQ was detected in six persons (two children and four elderly individuals). The degree of IQ conversion ranged from 26% (4-month-old girl) to 94% (81-year-old woman) of the initial quantity. Four Enterococcus isolates: two Enterococcus faecium and two Enterococcus faecalis strains, as well as one Clostridium difficile strain (LOCK 1030, from the culture collection) converted IQ to 7-OH-IQ. The genotoxicity of samples containing 7-OH-IQ was even three times higher (P < 0.05) than those with IQ and was correlated with the degree of IQ conversion and 7-OH-IQ concentration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Reduction and phenol acid depolymerization of Western US oil shale kerogen

    Energy Technology Data Exchange (ETDEWEB)

    Solash, J.; Cronauer, D.C.; Kobylinski, T.P.


    The chemical structure of U.S. Western oil shale kerogen is not known with certainty. Many structure studies employed strong oxidants to degrade kerogen. Acidic products are isolated and analyzed. In most cases, relatively small amounts of material are analyzed. Structural inferences from analysis of small quantities (generally less than 20% of kerogen) of degraded material are apt to be misleading. The literature is in conflict regarding even basic structural features of kerogen. Yen and coworkers have used X-ray analysis to deduce that kerogens contain very little aromatic material. However, /sup 13/C CP/MAS nmr measurements show that Western kerogens are 20-30% aromatic. The structure of nitrogen containing moieties is also in doubt. It has been suggested (8) that tetrapyrroles in kerogen pyrolyze to yield pyridines, quinolines, and other classes of nitrogeneous compounds found in shale oil. No quantitative data were given. Pyrolysis of simple pyrroles was found to give low yields of pyridines. Pyridines and quinolines are the major nitrogen-containing species in distillate shale oils. The authors' approach is to attempt to degrade Western U.S. oil shale kerogen under mild conditions. There has been a report of reducing kerogen using dissolving metals. Jones and Dickert reported that treating Colorado oil shale kerogen with lithium aluminum hydride, Hl, or lithium in ethylene diamine were all ineffective in increasing kerogen solubility. Interestingly, HI has been reported to convert kukersite to 100% ether and benzene solubles. No data were reported on the possible extent of reduction with lithium in ethylene diamine. The authors report results of treating kerogen with several well-known reagents.

  14. Ascorbic Acid (United States)

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops ...

  15. Acid mucopolysaccharides (United States)

    ... this page: // Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  16. Mefenamic Acid (United States)

    Mefenamic acid is used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Mefenamic acid is in a class of medications called NSAIDs. ...

  17. Obeticholic Acid (United States)

    Obeticholic acid is used alone or in combination with ursodiol (Actigall, Urso) to treat primary biliary cholangitis (PBC; a ... were not treated successfully with ursodiol alone. Obeticholic acid is in a class of medications called farnesoid ...

  18. Ethacrynic Acid (United States)

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  19. Amino acids (United States)

    ... this page: // Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  20. Decacarbonyl-1κ3C,2κ3C,3κ4C-μ-hydrido-1:2κ2H:H-(μ-quinoline-2-thiolato-1:2κ2S:Sdiosmium(Iosmium(0(3 Os—Os

    Directory of Open Access Journals (Sweden)

    Bai-Wang Sun


    Full Text Available The title compound, [Os3(C9H6NSH(CO10], contains a nearly equilateral triangle of Os atoms. Two of the Os atoms are bridged by an S atom of the quinoline-2-thiolate ligand. Ten carbonyl groups complete the cluster, resulting in a distorted octahedral geometry for each Os atom. The hydride atom, which was located in a difference Fourier map and refined isotropically, bridges the shortest Os–Os edge.

  1. Fatty acids - trans fatty acids (United States)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  2. Ibotenic acid and thioibotenic acid

    DEFF Research Database (Denmark)

    Hermit, Mette B; Greenwood, Jeremy R; Nielsen, Birgitte


    In this study, we have determined and compared the pharmacological profiles of ibotenic acid and its isothiazole analogue thioibotenic acid at native rat ionotropic glutamate (iGlu) receptors and at recombinant rat metabotropic glutamate (mGlu) receptors expressed in mammalian cell lines....... Thioibotenic acid has a distinct pharmacological profile at group III mGlu receptors compared with the closely structurally related ibotenic acid; the former is a potent (low microm) agonist, whereas the latter is inactive. By comparing the conformational energy profiles of ibotenic and thioibotenic acid...... with the conformations preferred by the ligands upon docking to mGlu1 and models of the other mGlu subtypes, we propose that unlike other subtypes, group III mGlu receptor binding sites require a ligand conformation at an energy level which is prohibitively expensive for ibotenic acid, but not for thioibotenic acid...

  3. Dual roles of extracellular signal-regulated kinase (ERK) in quinoline compound BPIQ-induced apoptosis and anti-migration of human non-small cell lung cancer cells. (United States)

    Fong, Yao; Wu, Chang-Yi; Chang, Kuo-Feng; Chen, Bing-Hung; Chou, Wan-Ju; Tseng, Chih-Hua; Chen, Yen-Chun; Wang, Hui-Min David; Chen, Yeh-Long; Chiu, Chien-Chih


    2,9-Bis[2-(pyrrolidin-1-yl)ethoxy]-6-{4-[2-(pyrrolidin-1-yl)ethoxy] phenyl}-11H-indeno[1,2-c]quinoline-11-one (BPIQ), is a synthetic quinoline analog. A previous study showed the anti-cancer potential of BPIQ through modulating mitochondrial-mediated apoptosis. However, the effect of BPIQ on cell migration, an index of cancer metastasis, has not yet been examined. Furthermore, among signal pathways involved in stresses, the members of the mitogen-activated protein kinase (MAPK) family are crucial for regulating the survival and migration of cells. In this study, the aim was to explore further the role of MAPK members, including JNK, p38 and extracellular signal-regulated kinase (ERK) in BPIQ-induced apoptosis and anti-migration of human non-small cell lung cancer (NSCLC) cells. Western Blot assay was performed for detecting the activation of MAPK members in NSCLC H1299 cells following BPIQ administration. Cellular proliferation was determined using a trypan blue exclusion assay. Cellular apoptosis was detected using flow cytometer-based Annexin V/propidium iodide dual staining. Cellular migration was determined using wound-healing assay and Boyden's chamber assay. Zymography assay was performed for examining MMP-2 and -9 activities. The assessment of MAPK inhibition was performed for further validating the role of JNK, p38, and ERK in BPIQ-induced growth inhibition, apoptosis, and migration of NSCLC cells. Western Blot assay showed that BPIQ treatment upregulates the phosphorylated levels of both MAPK proteins JNK and ERK. However, only ERK inhibitor rescues BPIQ-induced growth inhibition of NSCLC H1299 cells. The results of Annexin V assay further confirmed the pro-apoptotic role of ERK in BPIQ-induced cell death of H1299 cells. The results of wound healing and Boyden chamber assays showed that sub-IC50 (sub-lethal) concentrations of BPIQ cause a significant inhibition of migration in H1299 cells accompanied with downregulating the activity of MMP-2 and -9, the

  4. Okadaic acid

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H; Severinsen, Mai C K


    Okadaic acid (OA) is a polyether fatty acid produced by marine dinoflagellates and the causative agent of diarrhetic shellfish poisoning. The effect of OA on apical endocytosis in the small intestine was studied in organ cultured porcine mucosal explants. Within 0.5-1 h of culture, the toxin caused...... in acidic organelles, implying a different toxic mechanism of action. We propose that rapid induction of LBs, an indicator of phospholipidosis, should be included in the future toxicity profile of OA....

  5. Evaluation of preservative effectiveness of gallic acid derivatives in aluminum hydroxide gel-USP

    Directory of Open Access Journals (Sweden)

    Anurag Khatkar


    Full Text Available Background: Preservatives are added to most of the pharmaceutical preparations to prevent them from deterioration throughout their shelf life. Literature reveals that the common synthetic preservatives have many limitations, such as development of microbial resistance (in due course of time and several serious side-effects. Aim: The aim of this study is to find out new preservatives synthesized from natural sources, which may have better efficiency than the existing synthetic preservatives. The derivatives of naturally occurring gallic acid were subjected for their preservative efficacy study. Their preservative efficiency was evaluated and compared with the standard parabens. Materials and Methods: The selected amide, anilide and ester derivatives of gallic acid were subjected to preservative efficacy testing in an official antacid preparation, {aluminum hydroxide gel-USP (United States Pharmacopoeia} against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger as representative challenging microorganisms as per USP 2004 guidelines. Results: The selected derivatives were found to be effective against all selected strains and showed preservative efficacy comparable to that of standard and even better in case E. coli, C. albicans and A. niger. The 8-hydroxy quinoline ester derivative showed better preservative efficacy than standard as well as other derivatives. Conclusion: The newly synthesized gallic acid preservatives were found to be effective in the proposed pharmaceutical preparation (Aluminium Hydroxide Gel - USP. Also, the synthesized preservatives have shown comparative and even better efficacy than the existing parabens and hence they have potential for use in pharmaceutical preparations.

  6. Evaluation of preservative effectiveness of p-coumaric acid derivatives in aluminium hydroxide gel-USP

    Directory of Open Access Journals (Sweden)

    Anurag Khatkar


    Full Text Available Background: Deterioration of pharmaceutical preparations due to growth of microorganisms is a great challenge and need of preservation becomes very important. Literature reports about various problems associated with the existing synthetic preservatives such as development of microbial resistance (in due course of time and several serious side effects. Aim: The aim of the present study is to find out new preservatives synthesized from natural sources, which may have better efficiency than the existing synthetic preservatives. The derivatives of naturally occurring p-coumaric acid were subjected for their preservative efficacy study. Their preservative efficiency was evaluated and compared with the standard parabens. Materials and Methods: The selected amide, anilide and ester derivatives of p-coumaric acid were subjected to preservative efficacy testing in an official antacid preparation, (aluminium hydroxide gel-USP against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans and Aspergillus niger as representative challenging microorganisms as per USP 2004 guidelines. Results: The selected derivatives were found to be effective against all selected strains and showed preservative efficacy comparable to that of standard and even better in case E. coli, C. albicans and A. niger. The 8-hydroxy quinoline ester derivative showed better preservative efficacy than standard as well as other derivatives. Conclusion: The newly synthesized p- coumaric acid preservatives were found to be effective in the proposed pharmaceutical preparation (Aluminium Hydroxide Gel - USP. Also, the synthesized preservatives have shown comparative and even better efficacy than the existing parabens and hence they have potential for use in pharmaceutical preparations.

  7. QSAR analysis of a series of 2-aryl(heteroaryl)-2,5-dihydropyrazolo[4,3-c]quinolin-3-(3H)-ones using piecewise hyper-sphere modeling by particle swarm optimization

    Energy Technology Data Exchange (ETDEWEB)

    Lin Li [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Lin Weiqi [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Jiang Jianhui [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Zhou Yanping [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Shen Guoli [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Yu Ruqin [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China)]. E-mail:


    In the present work, we employed piecewise hyper-sphere modeling by particle swarm optimization (PHMPSO) which splits the dataset into subsets with desired linearity in each model for QSAR studies of a series of 2-aryl(heteroaryl)-2,5-dihydropyrazolo[4,3-c]quinolin-3-(3H)-ones (PQs) for their affinity to benzodiazepine receptor (BzR). The results were compared to those obtained by MLR modeling in a single model with the whole data set as well as in submodels based on K-means clustering analysis. It has been clearly shown that electronic descriptors and spatial descriptors play the important roles in the compounds' affinity to BzR. In addition, the molecular density, the Y component of the principal moment of inertia, the magnitude and the Y component of the dipole moment of the molecules can detrimentally affect PQ analogue BzR affinity, while the X component of the dipole moment of the molecules can favorably affect compounds' affinity.

  8. Estimation of protein concentration at high sensitivity using SDS-capillary gel electrophoresis-laser induced fluorescence detection with 3-(2-furoyl)quinoline-2-carboxaldehyde protein labeling. (United States)

    Arrell, Miriam S; Kálmán, Franka


    3-(2-furoyl)quinoline-2-carboxaldehyde (FQ) is a sensitive fluorogenic dye, used for derivatization of proteins for SDS-CGE with LIF detection (SDS-CGE-LIF) at silver staining sensitivity (ng/mL). FQ labels proteins at primary amines, found at lysines and N-termini, which vary in number and accessibility for different proteins. This work investigates the accuracy of estimation of protein concentration with SDS-CGE-LIF in real biological samples, where a different protein must be used as a standard. Sixteen purified proteins varying in molecular weight, structure, and sequence were labeled with FQ at constant mass concentration applying a commonly used procedure for SDS-CGE-LIF. The fluorescence of these proteins was measured using a spectrofluorometer and found to vary with a RSD of 36%. This compares favorably with other less sensitive methods for estimation of protein concentration such as SDS-CGE-UV and SDS-PAGE-Coomassie and is vastly superior to the equivalently sensitive silver stain. Investigation into the number of labels bound with UHPLC-ESI-QTOF-MS revealed large variations in the labeling efficiency (percentage of labels to the number of labeling sites given by the sequence) for different proteins (from 3 to 30%). This explains the observation that fluorescence per mole of protein was not proportional to the number of lysines in the sequence. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Fourier transform infrared spectra and normal mode analysis of 1-(3-methyl phenyl piperazin-1-yl)-2-(quinolin-2-yl)ethane (Centhaquin): a potent centrally acting anti-hypertensive agent (United States)

    Bajpai, U. C.; Gupta, D. C.; Singh, R. B.; Saxena, M.; Saxena, A. K.


    1-(3-methyl phenyl piperazin-1-yl)-2-(quinolin-2-yl) ethane (Centhaquin) and its analogs showed potent hypotensive activity. As the interaction of a drug with its receptor is the rate-limiting step in eliciting its biological response, the knowledge of its conformation is of key importance. The conformation of Centhaquin was determined by X-ray diffraction, but this determination is very hard for its analogs because of the difficulty in preparing their single crystals. A novel and easy approach is envisaged to determine the conformation in such cases by the application of molecular modeling, Fourier transform infrared (FTIR) spectroscopy and normal mode analysis. As a first step in this direction, the FTIR spectrum of the title compound was recorded and its normal mode analysis carried out. The assignments of the frequencies are based on the concept of group frequencies and band intensities. The theoretically calculated frequencies were tabulated along with the spectrally observed ones. Good agreement was obtained between them and a set of 45 force field constants was established.

  10. Synthesis, physicochemical and antimicrobial studies of first row transition metal complexes with quinoline derivatives nitroquinolino (3,2-b(1,5benzodixazepine and nitroquinolino(3,2-b(1,5benzoxazepine

    Directory of Open Access Journals (Sweden)

    Neeraj Sharma


    Full Text Available div align="justify">Metal complexes of Mn (II, Cu (II, Ni (II & Co (II with quinoline derivatives have been synthesized and characterized by elemental analysis, molar conductance, magnetic movement, electronic spectra, thermal analysis and IR spectral data. The molecular formula of complexes corresponds to [ML(NO32] where M = Mn ,Cu , Ni , Co , Zn , Fe, and Cr. The physicochemical and IR spectral data shows that the ligand coordinates to the metal ion in bidentate fashion (through the C=N and N-H groups. The antimicrobial studies of ligand and its metal, metal complexes have been screened for selected bacteria (E. Coli , S. typhi , B. subtilis and S. aureus and fungi (A. flavous, A. niger, P. triticena and F. species. Antimicrobial studies shows that the Mn (II complexes are more toxic than other metal complexes. Magnetic susceptibility measurements reveal octahedral geometry around the metal ion. The complexes were found to be non electrolyte in nature on the basis of low value of molar conductance.

  11. Comparative effects in rats of intact wheat bran and two wheat bran fractions on the disposition of the mutagen 2-amino-3-methylimidazo[4,5-f]quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, Lynnette R., E-mail: [Discipline of Nutrition, Faculty of Medicine and Health Sciences, University of Auckland, Auckland (New Zealand); Auckland Cancer Society Research Centre, Faculty of Medicine and Health Sciences, University of Auckland, Auckland (New Zealand); Harris, Philip J. [School of Biological Sciences, University of Auckland, Auckland (New Zealand); Kestell, Philip [Auckland Cancer Society Research Centre, Faculty of Medicine and Health Sciences, University of Auckland, Auckland (New Zealand); Zhu, Shuotun [Discipline of Nutrition, Faculty of Medicine and Health Sciences, University of Auckland, Auckland (New Zealand); Auckland Cancer Society Research Centre, Faculty of Medicine and Health Sciences, University of Auckland, Auckland (New Zealand); Munday, Rex; Munday, Christine M. [Agresearch, Ruakura Agricultural Research Centre, Hamilton (New Zealand)


    Wheat bran protects against mutations and cancer, but contains different plant cell types that are likely to have different protective effects. We previously described the production and chemical characterisation of an aleurone-rich fraction (ARF) and a pericarp-rich fraction (PRF) from wheat grain. We compared these with whole bran (WB), fed to rats as 10% of a high fat AIN-76 diet. All bran-supplemented diets increased faecal bulk, in the order PRF > WB > ARF. PRF increased the activity of NAD(P)H:quinone acceptor oxidoreductase only in the forestomach, whereas ARF and WB enhanced levels of glutathione S-transferase in the duodenum. ARF but not PRF was digested and fermented, and also encouraged bacterial growth. Rats were gavaged with the radioactive mutagen {sup 14}C-labelled IQ (2-amino-3-methylimidazo[4,5-f]quinoline), and effects of the brans on plasma radioactivity measured. Compared with the control diet, all bran-supplemented diets reduced the concentration of radioactivity in plasma, in the order ARF > PRF > WB. All brans increased faecal elimination of radioactivity, but only ARF and PRF enhanced urinary radioactivity. These data suggest that wheat bran may reduce mutation and cancers through direct adsorption and enhanced elimination of a dietary mutagen and/or its metabolites, and that wheat bran enriched in pericarp or aleurone cell walls may exert protective effects through different mechanisms.

  12. Short-term carcinogenicity testing of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methylimidazo[4,5-f] quinoline (IQ) in E mu-pim-1 transgenic mice

    DEFF Research Database (Denmark)

    Sørensen, Ilona Kryspin; Mortensen, Alicja; Kristiansen, E.


    ]pyridine (PhIP) for 7 months or with 0.03% 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) for 6 months, PhIP and IQ are heterocyclic amines formed during cooking of meat and fish and are mutagenic to bacteria and cultured mammalian cells, PhIP is a potent mouse lymphomagen, while IQ is a liver carcinogen...... and also causes lung tumors and tumors of the forestomach in mice. We found that transgenic E mu-pim-1 mice are highly susceptible to PhIP induced lymphomagenesis but do not respond to the IQ treatment, PhIP feeding of E mu-pim-1 mice not only increased the total number of T-cell lymphomas but also...... to non-transgenic mice. Our results suggest that the transgenic E mu-pim-1 mouse may be a useful model for short-term carcinogenicity screening of potential genotoxic carcinogens having the lymphoid system as target tissue, The carcinogen IQ which does not have the lymphoid system as a target...

  13. Structural, Optical, Electrical and Photoelectrical Properties of 2-Amino-4-(5-bromothiophen-2-yl)-5,6-dihydro-6-methyl-5-oxo-4H-pyrano[3,2-c] quinoline-3-carbonitrile Films (United States)

    Mansour, A. M.; El-Taweel, F. M. A.; Abu El-Enein, R. A. N.; El-Menyawy, E. M.


    2-Amino-4-(5-bromothiophen-2-yl)-5,6-dihydro-6-methyl-5-oxo-4H-pyrano[3,2-c] quinoline-3-carbonitrile (ABDQC) powder was synthesized and showed thermal stability up to 535 K. ABDQC films were successfully prepared using thermal evaporation. X-ray diffraction showed that the prepared ABDQC powder had a polycrystalline structure, whereas the deposited film had an amorphous structure. The surface morphology of the films was characterized by using a transmission electron microscope. Optical absorption properties of ABDQC films were investigated by spectrophotometric measurements of the transmittance and reflectance in the wavelength range 200-2500 nm. The films were found to have indirect allowed optical band gap of 2.5 eV. Current-voltage characteristics of Au/ABDQC/p-Si/Al were measured at different temperatures (300-420 K) in which the temperature dependence of the diode parameters has been discussed. Under illumination, the device showed open-circuit voltage and short-circuit current of 0.09 V and 3.26 × 10-4 A, respectively.

  14. Structural, Optical, Electrical and Photoelectrical Properties of 2-Amino-4-(5-bromothiophen-2-yl)-5,6-dihydro-6-methyl-5-oxo-4 H-pyrano[3,2-c] quinoline-3-carbonitrile Films (United States)

    Mansour, A. M.; El-Taweel, F. M. A.; Abu El-Enein, R. A. N.; El-Menyawy, E. M.


    2-Amino-4-(5-bromothiophen-2-yl)-5,6-dihydro-6-methyl-5-oxo-4 H-pyrano[3,2-c] quinoline-3-carbonitrile (ABDQC) powder was synthesized and showed thermal stability up to 535 K. ABDQC films were successfully prepared using thermal evaporation. X-ray diffraction showed that the prepared ABDQC powder had a polycrystalline structure, whereas the deposited film had an amorphous structure. The surface morphology of the films was characterized by using a transmission electron microscope. Optical absorption properties of ABDQC films were investigated by spectrophotometric measurements of the transmittance and reflectance in the wavelength range 200-2500 nm. The films were found to have indirect allowed optical band gap of 2.5 eV. Current-voltage characteristics of Au/ABDQC/ p-Si/Al were measured at different temperatures (300-420 K) in which the temperature dependence of the diode parameters has been discussed. Under illumination, the device showed open-circuit voltage and short-circuit current of 0.09 V and 3.26 × 10-4 A, respectively.

  15. A novel aromatic mutagen, 5-amino-6-hydroxy-8H-benzo[6,7]azepino[5,4,3-de]quinolin-7-one (ABAQ, induces colonic preneoplastic lesions in mice

    Directory of Open Access Journals (Sweden)

    Takahiro Kochi


    Full Text Available The benzoazepinoqunolinone derivative, 5-amino-6-hydroxy-8H-benzo[6,7]azepino[5,4,3-de]quinolin-7-one (ABAQ, which is produced in a mixture of glucose and tryptophan incubated at 37 °C under physiological conditions in the presence or absence of hydroxyl radicals caused by the Fenton reaction, is a novel aromatic mutagen. In the current study, we determined the tumor-initiating potency of ABAQ using an inflammation-relate, two-stage mouse colon carcinogenesis model. Male Crj: CD-1 (ICR mice were treated with the single intragastric administration (100 or 200 mg/kg body weight of ABAQ followed by subsequent 1-week oral exposure to 2% dextran sodium sulfate (DSS in drinking water. The ABAQ treatment alone resulted in high-grade dysplasia, which is a precursor to colorectal cancer, in the colon. Following the administration of DSS after ABAQ treatment, the incidence and frequency of high-grade dysplastic lesions increased; the values were highest in the mice treated with 200 mg/kg body weight of ABAQ followed by DSS. The lesions expressing β-catenin in their nuclei and cytoplasm exhibited high proliferation activity without the expression of programmed cell death 4. These findings indicate that ABAQ has a tumor-initiating activity in the mouse colon, with or without inflammation, although the potential pro-inflammatory effect of high doses of ABAC should be investigated.

  16. Valproic Acid (United States)

    ... and spinal cord and can also cause lower intelligence in babies exposed to valproic acid before birth. ... all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any ...

  17. Carnosic acid. (United States)

    Birtić, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc


    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (∼70 years ago) and its identification (∼50 years ago), numerous articles and patents (∼400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Acid Precipitation (United States)

    Likens, Gene E.


    Discusses the fact that the acidity of rain and snow falling on parts of the U.S. and Europe has been rising. The reasons are still not entirely clear and the consequences have yet to be well evaluated. (MLH)

  19. Folic Acid (United States)

    ... okra, asparagus, fruits (such as bananas, melons, and lemons) beans, yeast, mushrooms, meat (such as beef liver ... after angioplasty. There is inconsistent evidence on the benefits of taking folic acid after a procedure to ...

  20. Recent evidence for an expanded role of the kynurenine pathway of tryptophan metabolism in neurological diseases. (United States)

    Lovelace, Michael D; Varney, Bianca; Sundaram, Gayathri; Lennon, Matthew J; Lim, Chai K; Jacobs, Kelly; Guillemin, Gilles J; Brew, Bruce J


    The kynurenine pathway (KP) of tryptophan metabolism has emerged in recent years as a key regulator of the production of both neuroprotective (e.g. kynurenic and picolinic acid, and the essential cofactor NAD+) and neurotoxic metabolites (e.g. quinolinic acid, 3-hydroxykynurenine). The balance between the production of the two types of metabolites is controlled by key rate-limiting enzymes such as indoleamine-2,3-dioxygenase (IDO-1), and in turn, molecular signals such as interferon-γ (IFN-γ), which activate the KP metabolism of tryptophan by this enzyme, as opposed to alternative pathways for serotonin and melatonin production. Dysregulated KP metabolism has been strongly associated with neurological diseases in recent years, and is the subject of increasing efforts to understand how the metabolites are causative of disease pathology. Concurrent with these endeavours are drug development initiatives to use inhibitors to block certain enzymes in the pathway, resulting in reduced levels of neurotoxic metabolites (e.g. quinolinic acid, an excitotoxin and N-Methyl-d-Aspartate (NMDA) receptor agonist), while in turn enhancing the bioavailability of the neuroprotective metabolites such as kynurenic acid. Neurodegenerative diseases often have a substantial autoimmune or inflammatory component; hence a greater understanding of how KP metabolites influence the inflammatory cascade is required. Additionally, challenges exist in diseases like multiple sclerosis (MS) and motor neurone disease (MND), which do not have reliable biomarkers. Clinical diagnosis can often be prolonged in order to exclude other diseases, and often diagnosis occurs at an advanced state of disease pathology, which does not allow a lengthy time for patient assessment and intervention therapies. This review considers the current evidence for involvement of the KP in several neurological diseases, in biomarkers of disease and also the parallels that exist in KP metabolism with what is known in other

  1. Kynurenic acid and psychotic symptoms and personality traits in twins with psychiatric morbidity. (United States)

    Kegel, Magdalena E; Johansson, Viktoria; Wetterberg, Lennart; Bhat, Maria; Schwieler, Lilly; Cannon, Tyrone D; Schuppe-Koistinen, Ina; Engberg, Göran; Landén, Mikael; Hultman, Christina M; Erhardt, Sophie


    Increased cytokines and kynurenic acid (KYNA) levels in cerebrospinal fluid (CSF) have been reported in patients with schizophrenia and bipolar disorder. The aim of the present study was to investigate cytokines and kynurenines in the CSF of twin pairs discordant for schizophrenia or bipolar disorder and to study these CSF markers in relation to psychotic symptoms and personality traits. CSF levels of tryptophan (TRP), KYNA, quinolinic acid (QUIN), interleukin (IL)-6, IL-8 and tumor necrosis factor-alpha (TNF-α) were analyzed in 23 twins with schizophrenia or bipolar disorder, and in their not affected co-twins. Ratings of psychotic symptoms and personality traits were made using the Scales for Assessment of Negative and Positive symptoms, the Structured Clinical Interview for DSM-IV - Axis II Disorders, and the Schizotypal Personality Questionnaire - Brief. A total score for psychotic symptoms and personality traits was constructed for analysis. CSF KYNA was associated with the score for psychotic symptom and personality traits. TNF-α and IL-8 were associated, and the intra-pair differences scores of TNF-α and IL-8 were highly correlated. Intraclass correlations indicated genetic influences on CSF KYNA, TRP, IL-8 and TNF-α. The association between KYNA and psychotic symptoms further supports a role of KYNA in psychotic disorders. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Drugs with antidepressant properties affect tryptophan metabolites differently in rodent models with depression-like behavior. (United States)

    Eskelund, Amanda; Li, Yan; Budac, David P; Müller, Heidi K; Gulinello, Maria; Sanchez, Connie; Wegener, Gregers


    The metabolism of tryptophan through kynurenine and serotonin pathways is linked to depression. Here, effects of different drugs with antidepressant properties (vortioxetine, fluoxetine, and ketamine) on various tryptophan metabolites in different brain regions and plasma were examined using tandem mass spectrometry (LC-MS/MS), in Flinders Sensitive Line rats, a genetic rat model of depression, and its controls: Flinders Sensitive Line and Sprague-Dawley rats. Protein levels of kynurenine pathway enzymes were measured in the brains and livers of these rat strains. Furthermore, effects of vortioxetine on tryptophan metabolites were assessed in the cortical regions of lupus mice (MRL/MpJ-FasIpr ), a murine model of increased depression-like behavior associated with inflammation. Sustained vortioxetine or fluoxetine (at doses aimed to fully occupy serotonin transporter via food or drinking water for at least 14 days) reduced levels of the excitotoxin quinolinic acid (QUIN) in various brain regions in all rats. Furthermore, chronic vortioxetine reduced levels of QUIN in MRL/MpJ-FasIpr mice. Acute i.p. administration of fluoxetine (10 mg/kg) or vortioxetine (10 mg/kg) led to reduced brain 5-hydroxyindoleacetic acid in Sprague-Dawley rats (2, 4, 6, and 8 h) and a similar trend was evident in Flinders Sensitive Line and Flinders Sensitive Line rats after 4 h. In contrast, single or repeated administration of ketamine (15 mg/kg i.p.) did not induce significant changes in metabolite levels. In conclusion, sustained vortioxetine and fluoxetine administration decreased QUIN independent of species, while ketamine was ineffective. These results support the hypothesis that modulating tryptophan metabolism may be part of the mechanism of action for some antidepressants. © 2017 International Society for Neurochemistry.

  3. Fluorescent sensors based on quinoline-containing styrylcyanine: determination of ferric ions, hydrogen peroxide, and glucose, pH-sensitive properties and bioimaging. (United States)

    Yang, Xiaodong; Zhao, Peiliang; Qu, Jinqing; Liu, Ruiyuan


    A novel styrylcyanine-based fluorescent probe 1 was designed and synthesized via facile methods. Ferric ions quenched the fluorescence of probe 1, whereas the addition of ferrous ions led to only small changes in the fluorescence signal. When hydrogen peroxide was introduced into the solution containing probe 1 and Fe(2+) , Fe(2+) was oxidized to Fe(3+), resulting in the quenching of the fluorescence. The probe 1/Fe(2+) solution fluorescence could also be quenched by H2 O2 released from glucose oxidation by glucose oxidase (GOD), which means that probe 1/Fe(2+) platform could be used to detect glucose. Probe 1 is fluorescent in basic and neutral media but almost non-fluorescent in strong acidic environments. Such behaviour enables it to work as a fluorescent pH sensor in both the solution and solid states and as a chemosensor for detecting volatile organic compounds with high acidity and basicity. Subsequently, the fluorescence microscopic images of probe 1 in live cells and in zebrafish were achieved successfully, suggesting that the probe has good cell membrane permeability and a potential application for imaging in living cells and living organisms. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Lipoic Acid

    Directory of Open Access Journals (Sweden)

    Ramazan Tetikcok


    Full Text Available Lipoic acid, which is defined as a miralce antioxidan, is used by many departments. Eventhough clinical using data are very limited , it is used in treatment of diabetic neuropathy, physical therapy and rehabilitation clinic, dermatology clinic, geriatric clinics. It has usage area for cosmetic purposes. Although there are reports there are the direction of the effectiveness in these areas, the works done are not enough. Today lipoic acid , used in many areas ,is evaluated as universal antioxidant [J Contemp Med 2015; 5(3.000: 206-209

  5. Quinoline-2-carboimine copper complex immobilized on amine functionalized silica coated magnetite nanoparticles: a novel and magnetically retrievable catalyst for the synthesis of carbamates via C-H activation of formamides. (United States)

    Sharma, R K; Dutta, Sriparna; Sharma, Shivani


    In the present study, we report the synthesis of a highly efficient and magnetically retrievable catalytic system (Cu-2QC@Am-SiO2@Fe3O4) through the covalent immobilization of quinoline-2-carboxaldehyde (2QC) on an amine functionalized silica coated ferrite nanosupport followed by metallation with copper acetate. The structure of the organic-inorganic hybrid nanomaterial has been confirmed using various physicochemical techniques such as Powder X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray Spectroscopy (EDS), Energy Dispersive X-Ray Fluorescence Spectroscopy (ED-XRF), Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma Spectroscopy (ICP) and Vibrating Sample Magnetometry (VSM). The resulting nanocatalyst exhibits a remarkable catalytic efficacy in the synthesis of industrially and pharmaceutically significant carbamates via the C-H activation of formamides under solvent free conditions. The most important attribute of the present methodology is that the catalyst can be recovered simply through an external magnetic force and reused several times without any significant deterioration in its activity. Furthermore, the heterogeneity test has been carried out in order to ensure the intrinsic stability of the nanostructured catalyst. The activity of the Cu-2QC@Am-SiO2@Fe3O4 nanocatalyst has been found to be far more superior in comparison with the literature precedents in terms of the product yield, cost and reusability of the catalyst. Besides, ambient reaction conditions, simple workup procedure, wide substrate scope and cost effectiveness are some of the other outstanding features of this protocol that make it economical and sustainable.

  6. Dammar resin, a non-mutagen, induces [corrected] oxidative stress and metabolic enzymes in the liver of gpt delta transgenic mouse which is different from a mutagen, 2-amino-3-methylimidazo[4,5-f]quinoline. (United States)

    Xie, Xiao-Li; Wei, Min; Kakehashi, Anna; Yamano, Shotaro; Okabe, Kyoko; Tajiri, Masaki; Wanibuchi, Hideki


    Dammar resin has long been used in foods as either a clouding or a glazing agent. In a recent study, 2% Dammar resin showed significant hepatocarcinogenicity in a rat 2-year bioassay. Therefore, for an accurate estimate of human risk, it is necessary to understand whether Dammar resin induces liver genotoxicity and the underlying mechanisms of its hepatocarcinogenicity. Modifying effects of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), a typical genotoxic carcinogen produced during cooking of protein-rich foods, was also studied in the present study. Exposure of gpt delta mice to Dammar resin at a dose of 2% for 12 weeks did not induce any obvious mutagenicity in the liver. However, the index of cell proliferation, the level of 8-OHdG, and bax, bcl-2, p53, cyp1a2, cyp2e1, gpx1 and gstm2 gene expression were all significantly increased when compared with the control group. In the IQ treatment group, at a dose of 300ppm, mutagenicity was readily detected, the index of cell proliferation increased, and p53, cyp2e1 and gpx1 gene expression was down-regulated in the liver. Down-regulation of p53, P450s, and gpx1 in the livers of IQ treated mice are consistent with its genotoxic mechanism of carcinogenicity observed in a 675-day study. In contrast, our results using gpt delta mice suggest that Dammar resin is not genotoxic. Instead, the Dammar resin-induced hepatocarcinogenicity seen in our previous 2-year study with rats may have been mediated by non-genotoxic mechanisms, including increased P450 enzyme activity, increased oxidative stress, altered gene expression, and promotion of cell proliferation. © 2012 Elsevier B.V. All rights reserved.

  7. Synthesis of samarium complexes with the derivative binder of Schiff Quinolinic base. Characterization and photophysical study; Sintesis de complejos de samario con el ligante derivado de base de Schiff Quinolinica. Caracterizacion y estudio fotofisico

    Energy Technology Data Exchange (ETDEWEB)

    Lucas H, J.


    In this work we determined the metal: binder stoichiometry of the species formed during the UV/Vis spectrophotometric titration of the derivative binder of Schiff quinolinic base, L1 with the samarium nitrate pentahydrate in methanol. Statistical analysis of the data allowed proposing the metal: binder stoichiometry for the synthesis of the complexes which was one mole of samarium salt by 2.5 moles of binder and thus favor the formation of complexes with 1M: 1L and 1M: 2L stoichiometries. They were synthesized in aqueous-organic medium (water-ethanol), isolated and purified two complexes with stoichiometry 1 Sm: 1 L1, complex 1 and 1 Sm: 2 L1, complex 2. The overall yield of the reaction was 76%. The characterization of the formed complexes was performed by visible ultraviolet spectrometry (UV/Vis), nuclear magnetic resonance, X-ray photoelectron spectroscopy (XP S), thermal gravimetric analysis with differential scanning calorimetry (TGA/DSC), and radial distribution function. These complexes were studied by fluorescence and emission phosphorescence at variable temperature. Spectroscopic techniques used in both solution and solid demonstrated the formation and stability of these complexes. In addition XP S indicated that in both complexes the samarium retains its oxidation state 3+. Luminescence studies indicated that there is intra-binding charge transfer which decreases the transfer of light energy from the binder to the samarium. Based on the experimental results, L1 binder molecules and complexes 1 and 2 were modeled that demonstrated the proposed Nc for each complex, as well as allowed to visualize the structural arrangement of the molecules, complexes and binder. (Author)

  8. Nonsteroidal selective glucocorticoid modulators: the effect of C-10 substitution on receptor selectivity and functional potency of 5-allyl-2,5-dihydro-2,2,4-trimethyl-1H-[1]benzopyrano[3,4-f]quinolines. (United States)

    Kym, Philip R; Kort, Michael E; Coghlan, Michael J; Moore, Jimmie L; Tang, Rui; Ratajczyk, James D; Larson, Daniel P; Elmore, Steven W; Pratt, John K; Stashko, Michael A; Falls, H Douglass; Lin, Chun W; Nakane, Masake; Miller, Loan; Tyree, Curtis M; Miner, Jeffery N; Jacobson, Peer B; Wilcox, Denise M; Nguyen, Phong; Lane, Benjamin C


    The preparation and characterization of a series of C-10 substituted 5-allyl-2,5-dihydro-2,2,4-trimethyl-1H-[1]benzopyrano[3,4-f]quinolines as a novel class of selective ligands for the glucocorticoid receptor is described. Substitution at the C-10 position of the tetracyclic core with linear, two-atom appendages (OCH(3), OCF(2)H, NHMe, SMe, CH=CH(2), Ctbd1;CH, CH(2)OH) provided molecules of high affinity (K(i) = 2-8 nM) for the human glucocorticoid receptor (hGR) with limited cross-reactivity with other steroid receptors (PR, MR, AR, ER). Optimal analogues showed slightly less potent but highly efficacious E-selectin repression with reduced levels of GRE activation efficacy in reporter gene assays relative to prednisolone. Preliminary SAR of analogues containing substitution at the C-9 and C-10 positions identified the 9-OH, 10-OMe analogue 50 and the 9-OH, 10-Cl analogue 58 as compounds that demonstrated potent, GR-mediated inhibition in a conconavalin A stimulated T-cell proliferation assay in both rodent and human whole blood monocytes. When evaluated for their in vivo effects in carrageenan-induced paw edema in rats, 50, 58, and 10-OCF(2)H analogue 35 showed dose-dependent anti-inflammatory effects (50, ED(50) = 16 mg/kg; 58, ED(50) = 15 mg/kg; 35, ED(50) = 21 mg/kg vs ED(50) = 15 mg/kg for 18 and ED(50) = 4 mg/kg for prednisolone).

  9. Synthesis, Characterization and Biological Activities of Cu(II, Co(II, Mn(II, Fe(II, and UO2(VI Complexes with a New Schiff Base Hydrazone: O-Hydroxyacetophenone-7-chloro-4-quinoline Hydrazone

    Directory of Open Access Journals (Sweden)

    Nora H. Al-Shaalan


    Full Text Available The Schiff base hydrazone ligand HL was prepared by the condensation reaction of 7-chloro-4-quinoline with o-hydroxyacetophenone. The ligand behaves either as monobasic bidentate or dibasic tridentate and contain ONN coordination sites. This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II, Ni(II, Co(II, Mn(II, UO2 (VI and Fe(II to form either mono- or binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, NMR, Mass, and UV-Visible spectra. The magnetic moments and electrical conductance of the complexes were also determined. The Co(II, Ni(II and UO2 (VI complexes are mononuclear and coordinated to NO sites of two ligand molecules. The Cu(II complex has a square-planar geometry distorted towards tetrahedral, the Ni(II complex is octahedral while the UO2 (VI complex has its favoured heptacoordination. The Co(II, Mn(II complexes and also other Ni(II and Fe(III complexes, which were obtained in the presence of Li(OH as deprotonating agent, are binuclear and coordinated via the NNNO sites of two ligand molecules. All the binuclear complexes have octahedral geometries and their magnetic moments are quite low compared to the calculated value for two metal ions complexes and thus antiferromagnetic interactions between the two adjacent metal ions. The ligand HL and metal complexes were tested against a strain of Gram +ve bacteria (Staphylococcus aureus, Gram −ve bacteria (Escherichia coli, and fungi (Candida albicans. The tested compounds exhibited high antibacterial activities.

  10. Molecular docking, discovery, synthesis, and pharmacological properties of new 6-substituted-2-(3-phenoxyphenyl)-4-phenyl quinoline derivatives; an approach to developing potent DNA gyrase inhibitors/antibacterial agents. (United States)

    Alagumuthu, Manikandan; Arumugam, Sivakumar


    Synthesis and molecular validation of 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives (4a-h) as antibacterial/DNA gyrase inhibitors reported. Primarily, 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives were docked into the active sites of DNA gyrase A&B, to ensure the binding mode of the compounds, and the results were superior on DNA gyrase A over DNA gyrase B. Based on this, S. aureus DNA gyrase A assay was proposed and executed. Most prominent DNA gyrase inhibition showed by 6-fluoro-2-(3-phenoxyphenyl)-4-phenylquinoline (4c), IC50 0.389μg/mL; 2-(3-phenoxyphenyl)-4-phenylquinolin-6-ol (4e), IC50 0.328μg/mL; and 5,7-dichloro-2-(3-phenoxyphenyl)-4-phenylquinolin-6-ol (4h), IC50 0.214μg/mL which were substituted with fluorine (4F), nitrile (4CN), hydroxyl group (4OH) and dichloro-hydroxyl (3,5Cl, 4OH) groups in the quinoline scaffold. Antimicrobial activity on Gram-ve bacteria Escherichia coli (MTCC 443), Pseudomonas aeruginosa (MTCC 424), and Gram+ve bacteria Staphylococcus aureus (MTCC 96) and Streptococcus pyogenes (MTCC 442) was evaluated. Excellent antibacterial activity showed by S. aureus and S. pyogenes which indicates the activity dominance of 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives on Gram+ve bacteria rather than Gram-ve. Subsequently, the cytotoxicity of 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives was evaluated. Cytotoxicity results of MCF-7 (human breast cancer) and G361 (skin melanoma cancer) cell lines reveals that the 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives are highly toxic to cancer cells. Predicted SAR, Lipinski's filter, Pharmacokinetic, and ADMET properties were also ensured the druggability probabilities of most favorable compounds among 6-substituted-2-(3-phenoxyphenyl)-4-phenylquinoline derivatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Perfluorooctanoic acid

    NARCIS (Netherlands)

    de Voogt, P.; Wexler, P.


    Perfluorooctanoic acid (PFOA, 335-67-1) is used in fluoropolymer production and firefighting foams and persists in the environment. Human exposure to PFOA is mostly through the diet. PFOA primarily affects the liver and can cause developmental and reproductive toxic effects in test animals.

  12. Structure-Based Discovery of 4-(6-Methoxy-2-methyl-4-(quinolin-4-yl)-9 H -pyrimido[4,5- b ]indol-7-yl)-3,5-dimethylisoxazole (CD161) as a Potent and Orally Bioavailable BET Bromodomain Inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yujun; Bai, Longchuan; Liu, Liu; McEachern, Donna; Stuckey, Jeanne A.; Meagher, Jennifer L.; Yang, Chao-Yie; Ran, Xu; Zhou, Bing; Hu, Yang; Li, Xiaoqin; Wen, Bo; Zhao, Ting; Li, Siwei; Sun, Duxin; Wang, Shaomeng (Michigan)


    We have designed and synthesized 9H-pyrimido[4,5-b]indole-containing compounds to obtain potent and orally bioavailable BET inhibitors. By incorporation of an indole or a quinoline moiety to the 9H-pyrimido[4,5-b]indole core, we identified a series of small molecules showing high binding affinities to BET proteins and low nanomolar potencies in inhibition of cell growth in acute leukemia cell lines. One such compound, 4-(6-methoxy-2-methyl-4-(quinolin-4-yl)-9H-pyrimido[4,5-b]indol-7-yl)-3,5-dimethylisoxazole (31) has excellent microsomal stability and good oral pharmacokinetics in rats and mice. Orally administered, 31 achieves significant antitumor activity in the MV4;11 leukemia and MDA-MB-231 triple-negative breast cancer xenograft models in mice. Determination of the cocrystal structure of 31 with BRD4 BD2 provides a structural basis for its high binding affinity to BET proteins. Testing its binding affinities against other bromodomain-containing proteins shows that 31 is a highly selective inhibitor of BET proteins. Our data show that 31 is a potent, selective, and orally active BET inhibitor.

  13. Levulinic acid

    Directory of Open Access Journals (Sweden)

    Barbara Hachuła


    Full Text Available The title compound (systematic name: 4-oxopentanoic acid, C5H8O3, is close to planar (r.m.s. deviation = 0.0762 Å. In the crystal, the molecules interact via O—H...O hydrogen bonds in which the hydroxy O atoms act as donors and the ketone O atoms in adjacent molecules as acceptors, forming C(7 chains along [20-1].

  14. Synthesis of quinoline attached-furan-2(3H-ones having anti-inflammatory and antibacterial properties with reduced gastro-intestinal toxicity and lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Akhter Mymoona


    Full Text Available A series of 3-[2-chloroquinolin-3-ylmethylene]-5-aryl-furan-2(3H-ones {3(a-p} were synthesized. The required 3-(substitutedbenzoyl propionic acids {2(a-d} were prepared under Friedal Craft acylation reaction conditions. The substituted 2-chloroquinoline-3-carbaldehydes {1(a-d} were synthesized by reaction of substitutedphenylethanone-oxime with phosphorus oxychloride in presence of dimethyl formamide using the Vilsmeir Haack reaction method. These compounds were screened for their anti-inflammatory and antibacterial activities along with their ulcerogenic and lipid peroxidation potentials. The compounds that showed significant anti-inflammatory activity were further screened for their analgesic activity. The compounds were less toxic in terms of ulcerogenicity as compared to a standard, which was also supported by lipid peroxidation studies. The antibacterial activities were performed against Staphylococcus aureus and Escherichia coli. Compounds 3f, 3n and 3o showed significant activity against both S. aureus and E. coli having an MIC value of 6.25μg mL-1.

  15. Hydroxycarboxylic acids and salts

    Energy Technology Data Exchange (ETDEWEB)

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N


    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  16. Comparative analysis of QSAR models for predicting pK(a) of organic oxygen acids and nitrogen bases from molecular structure. (United States)

    Yu, Haiying; Kühne, Ralph; Ebert, Ralf-Uwe; Schüürmann, Gerrit


    For 1143 organic compounds comprising 580 oxygen acids and 563 nitrogen bases that cover more than 17 orders of experimental pK(a) (from -5.00 to 12.23), the pK(a) prediction performances of ACD, SPARC, and two calibrations of a semiempirical quantum chemical (QC) AM1 approach have been analyzed. The overall root-mean-square errors (rms) for the acids are 0.41, 0.58 (0.42 without ortho-substituted phenols with intramolecular H-bonding), and 0.55 and for the bases are 0.65, 0.70, 1.17, and 1.27 for ACD, SPARC, and both QC methods, respectively. Method-specific performances are discussed in detail for six acid subsets (phenols and aromatic and aliphatic carboxylic acids with different substitution patterns) and nine base subsets (anilines, primary, secondary and tertiary amines, meta/para-substituted and ortho-substituted pyridines, pyrimidines, imidazoles, and quinolines). The results demonstrate an overall better performance for acids than for bases but also a substantial variation across subsets. For the overall best-performing ACD, rms ranges from 0.12 to 1.11 and 0.40 to 1.21 pK(a) units for the acid and base subsets, respectively. With regard to the squared correlation coefficient r², the results are 0.86 to 0.96 (acids) and 0.79 to 0.95 (bases) for ACD, 0.77 to 0.95 (acids) and 0.85 to 0.97 (bases) for SPARC, and 0.64 to 0.87 (acids) and 0.43 to 0.83 (bases) for the QC methods, respectively. Attention is paid to structural and method-specific causes for observed pitfalls. The significant subset dependence of the prediction performances suggests a consensus modeling approach.

  17. Ferrocenylphosphonic acid

    Directory of Open Access Journals (Sweden)

    Bao-Zhang Yang


    Full Text Available In the title compound, [Fe(C5H5(C5H6O3P], the phosphate group is bonded to the ferrocene unit with a P—C bond length of 1.749 (3 Å. In the crystal, six ferrocenylphosphonic acid molecules are connected by 12 strong intermolecular O—H...O hydrogen bonds, leading to the formation of a highly distorted octahedral cage. The volume of the octahedral cage is about 270 Å3.

  18. Fluorescence spectroscopy as a means of distinguishing fulvic and humic acids from dissolved and sedimentary aquatic sources and terrestrial sources (United States)

    Senesi, Nicola; Miano, Teodoro M.; Provenzano, Maria Rosaria

    Thirteen fulvic acids (FA) and humic acids (HA) isolated from river waters and sediment, marine sediments, leonardite, soils, and paleosol, have been investigated by fluorescence spectroscopy in the emission, excitation and, partly, synchronous scan excitation modes. Emission spectra are generally characterized by a unique broad band, whereas excitation spectra exhibit a variable number of peaks or shoulders of various intensity; these peaks are particularly well-resolved for sedimentary HA samples. A decrease in the relative intensity of fluorescence, which is associated with a red-shift (longer wavelengths) of both the emission maximum and the main excitation peaks, is observed when passing from dissolved aquatic and soil FA to river and marine sedimentary HA, to leonardite and soil HA, and, finally, to paleosol HA. Evident differences are shown in the relative intensity and wavelength maxima, measured in any mode, between soil FA and HA from the same source. For FA and HA of various nature and origin, the fluorescence is suggested to be caused by chemically different structural units. These units fluoresce from the blue-violet to the green and consist of variously extended, condensed, aromatic and/or heterocyclic ring systems, with a high degree of electronic conjugation and bearing suitable hydroxyl, alkoxyl and carbonyl groups (e.g. salicyl, cinnamic and hydroxybenzoic derivatives, naphtols, naphtoquinones, coumarin), and quinoline-derivatives, flavonoids and Schiffbase derivatives. Fluorescence properties of humic substances may represent an additional diagnostic criterium useful in distinguishing between FA and HA from the same or various natural sources.

  19. Folic Acid and Pregnancy (United States)

    ... Teens a Voice in Health Care Decisions Folic Acid and Pregnancy KidsHealth > For Parents > Folic Acid and ... conception and during early pregnancy . What Is Folic Acid? Folic acid, sometimes called folate, is a B ...

  20. New bioactive fatty acids (United States)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  1. Sulfonic acid functionalized boron nitride nanomaterials as a microwave-assisted efficient and highly biologically active one-pot synthesis of piperazinyl-quinolinyl fused Benzo[c]acridine derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Murugesan, Arul; Gengan, R.M., E-mail:; Krishnan, Anand


    Boron nitride nano material based solid acid catalyst was found to be an efficient and reusable sulfonic acid catalyst for the synthesis of one-pot Knoevenagel and Michael type reactions in 3, 3-dimethyl-9-(2-(4-methylpiperazin-1-yl) quinolin-3-yl)-3, 4, 9, 10-tetrahydroacridin-1(2H)-one derivatives under microwave irradiation conditions. The catalyst was prepared by mixing boron nitrile and (3-mercaptopropyl) trimethoxysilane. This is simple and safe method for the preparation of solid acid catalysts. The morphological properties of catalyst determined by using FT-IR, XRD, TEM, SEM and Raman spectroscopy. The synthesised catalyst was employed in Knoevenagel and Michael type reactions to synthesise novel piperazinyl-quinolinyl based acridine derivatives. Furthermore the newly-synthesised compounds have been used for molecular docking in DNA binding studies. The method developed in this study has the advantages of good yield, simplicity coupled with safety and short reaction time. Most importantly it was found that the solid acid catalyst can be recycled with only 5% loss of activity. - Highlights: • One-pot Synthesis of Knoevenagel and Michel type reactions. • Synthesis of Sulfonic acid Functionalized Boron nitride nano materials. • Synthesis of piperazinyl-quinolinyl fused Benzo[c]acridine derivatives under Microwave irradiation. • Molecular docking studies were performed on piperazinyl-quinolinyl acridine derivatives using DNA.

  2. Xanthurenic Acid Formation from 3-Hydroxykynurenine in the Mammalian Brain: Neurochemical Characterization and Physiological Effects. (United States)

    Sathyasaikumar, K V; Tararina, M; Wu, H-Q; Neale, S A; Weisz, F; Salt, T E; Schwarcz, R


    Xanthurenic acid (XA), formed from 3-hydroxykynurenine (3-HK) in the kynurenine pathway of tryptophan degradation, may modulate glutamatergic neurotransmission by inhibiting the vesicular glutamate transporter and/or activating Group II metabotropic glutamate receptors. Here we examined the molecular and cellular mechanisms by which 3-HK controls the neosynthesis of XA in rat, mouse and human brain, and compared the physiological actions of 3-HK and XA in the rat brain. In tissue homogenates, XA formation from 3-HK was observed in all three species and traced to a major role of kynurenine aminotransferase II (KAT II). Transamination of 3-HK to XA was also demonstrated using human recombinant KAT II. Neosynthesis of XA was significantly increased in the quinolinate-lesioned rat striatum, indicating a non-neuronal localization of the process. Studies using rat cortical slices revealed that newly produced XA is rapidly released into the extracellular compartment, and that XA biosynthesis can be manipulated experimentally in the same way as the production of kynurenic acid from kynurenine (omission of Na+ or glucose, depolarizing conditions, or addition of 2-oxoacids). The synthesis of XA from 3-HK was confirmed in vivo by striatal microdialysis. In slices from the rat hippocampus, both 3-HK and XA reduced the slopes of dentate gyrus field EPSPs. The effect of 3-HK was reduced in the presence of the KAT inhibitor aminooxyacetic acid. Finally, both 3-HK and XA reduced the power of gamma-oscillatory activity recorded from the hippocampal CA3 region. Endogenous XA, newly formed from 3-HK, may therefore play a physiological role in attentional and cognitive processes. Copyright © 2017. Published by Elsevier Ltd.

  3. 3-Hydroxykynurenine and 3-hydroxyanthranilic acid generate hydrogen peroxide and promote alpha-crystallin cross-linking by metal ion reduction. (United States)

    Goldstein, L E; Leopold, M C; Huang, X; Atwood, C S; Saunders, A J; Hartshorn, M; Lim, J T; Faget, K Y; Muffat, J A; Scarpa, R C; Chylack, L T; Bowden, E F; Tanzi, R E; Bush, A I


    The kynurenine pathway catabolite 3-hydroxykynurenine (3HK) and redox-active metals such as copper and iron are implicated in cataractogenesis. Here we investigate the reaction of kynurenine pathway catabolites with copper and iron, as well as interactions with the major lenticular structural proteins, the alpha-crystallins. The o-aminophenol kynurenine catabolites 3HK and 3-hydroxyanthranilic acid (3HAA) reduced Cu(II)>Fe(III) to Cu(I) and Fe(II), respectively, whereas quinolinic acid and the nonphenolic kynurenine catabolites kynurenine and anthranilic acid did not reduce either metal. Both 3HK and 3HAA generated superoxide and hydrogen peroxide in a copper-dependent manner. In addition, 3HK and 3HAA fostered copper-dependent alpha-crystallin cross-linking. 3HK- or 3HAA-modifed alpha-crystallin showed enhanced redox activity in comparison to unmodified alpha-crystallin or ascorbate-modified alpha-crystallin. These data support the possibility that 3HK and 3HAA may be cofactors in the oxidative damage of proteins, such as alpha-crystallin, through interactions with redox-active metals and especially copper. These findings may have relevance for understanding cataractogenesis and other degenerative conditions in which the kynurenine pathway is activated.

  4. Virus-induced gene silencing identifies Catharanthus roseus 7-deoxyloganic acid-7-hydroxylase, a step in iridoid and monoterpene indole alkaloid biosynthesis. (United States)

    Salim, Vonny; Yu, Fang; Altarejos, Joaquín; De Luca, Vincenzo


    Iridoids are a major group of biologically active molecules that are present in thousands of plant species, and one versatile iridoid, secologanin, is a precursor for the assembly of thousands of monoterpenoid indole alkaloids (MIAs) as well as a number of quinoline alkaloids. This study uses bioinformatics to screen large databases of annotated transcripts from various MIA-producing plant species to select candidate genes that may be involved in iridoid biosynthesis. Virus-induced gene silencing of the selected genes combined with metabolite analyses of silenced plants was then used to identify the 7-deoxyloganic acid 7-hydroxylase (CrDL7H) that is involved in the 3rd to last step in secologanin biosynthesis. Silencing of CrDL7H reduced secologanin levels by at least 70%, and increased the levels of 7-deoxyloganic acid to over 4 mg g(-1) fresh leaf weight compared to control plants in which this iridoid is not detected. Functional expression of this CrDL7H in yeast confirmed its biochemical activity, and substrate specificity studies showed its preference for 7-deoxyloganic acid over other closely related substrates. Together, these results suggest that hydroxylation precedes carboxy-O-methylation in the secologanin pathway in Catharanthus roseus. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  5. Synthesis in aqueous medium and organic praseodymium complexes with ligands derived from Schiff base quinolinic. Characterization and physicochemical study; Sintesis en medio acuoso y organico de complejos de praseodimio con ligantes derivados de base de Schiff quinolicos. Caracterizacion y estudio fisicoquimico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia G, A.


    It was investigated the coordination ability of the quinolinic Schiff base organic tetradentate quinolinic ligand (Q Schiff-(OH){sub 2}) towards the trivalent praseodymium by UV/Vis spectrophotometric titration (St). By St, was studied the formed species between the Q Schiff-(OH){sub 2} ligand and the praseodymium nitrate salt in equimolar concentrations (5.86 x 10{sup -4} M: 5.22 x 10{sup -4} M) in methanol. The statistical analysis of the experimental results suggested three complexed species with 1Pr:3L, 1Pr:2L y 1Pr:1L stoichiometries. The predominant stoichiometries were the second and the latter. Based on these results and data from the scientific literature, the methodology for the syntheses of the complexes Q Schiff-(OH){sub 2}-Pr in aqueous-organic and organic media was established and a molar ratio M:L= 1:2 of praseodymium nitrate and the ligand was used. The new complexes were characterized by UV/Vis, Infrared, X-ray Photoelectron Spectroscopy (XP S), Diffuse Reflectance (Dr) and Thermogravimetric Analysis/Differential Scanning Calorimetry (TGA/DSC). Elemental analysis of C, N, O and Pr by XP S suggested 1Pr:2L:1Na (PrC{sub 32}H{sub 20}N{sub 4}O{sub 4}Na) stoichiometry of the complex synthesized by the aqueous-organic medium while for the complex synthesized by the organic medium it was 1Pr:3L (PrC{sub 48}H{sub 33}N{sub 6}O{sub 6}). In the first case, the praseodymium ion charge was neutralized by the anionic ligands whose remaining charge was compensated by the sodium ion. In the second case, the ion charge was neutralized by the ligands. The minimum formula was Pr(Q Schiff){sub 2}Na for the pure coordination compound from the aqueous-organic medium and the minimum formula Pr(Q Schiff){sub 3} for that from the organic medium. XP S also indicated that the oxidation state of praseodymium ion was maintained. Both complexes were stable in methanol, ethanol and acetonitrile at least for 5 days. The photophysical properties of the studied complexes were

  6. Crystal structures of two 1:2 dihydrate compounds of chloranilic acid with 2-carboxypyridine and 2-carboxyquinoline

    Directory of Open Access Journals (Sweden)

    Kazuma Gotoh


    Full Text Available The crystal structure of the 1:2 dihydrate compound of chloranilic acid (systematic name: 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone with 2-carboxypyridine (another common name: picolinic acid; systematic name: pyridine-2-carboxylic acid, namely, 2C6H5.5NO20.5+·C6HCl2O4−·2H2O, (I, has been determined at 180 K, and the structure of the 1:2 dihydrate compound of chloranilic acid with 2-carboxyquinoline (another common name: quinaldic acid; systematic name: quinoline-2-carboxylic acid, namely, 2C10H7NO2·C6H2Cl2O4·2H2O, (II, has been redetermined at 200 K. This determination presents a higher precision crystal structure than the previously published structure [Marfo-Owusu & Thompson (2014. X-ray Struct. Anal. Online, 30, 55–56]. Compound (I was analysed as a disordered structure over two states, viz. salt and co-crystal. The salt is bis(2-carboxypyridinium chloranilate dihydrate, 2C6H6NO2+·C6Cl2O42−·2H2O, and the co-crystal is bis(pyridinium-2-carboxylate chloranilic acid dihydrate, 2C6H5NO2·C6H2Cl2O4·2H2O, including zwitterionic 2-carboxypyridine. In both salt and co-crystal, the water molecule links the chloranilic acid and 2-carboxypyridine molecules through O—H...O and N—H...O hydrogen bonds. The 2-carboxypyridine molecules are connected into a head-to-head inversion dimer by a short O—H...O hydrogen bond, in which the H atom is disordered over two positions. Compound (II is a 1:2 dihydrate co-crystal of chloranilic acid and zwitterionic 2-carboxyquinoline. The water molecule links the chloranilic acid and 2-carboxyquinoline molecules through O—H...O hydrogen bonds. The 2-carboxyquinoline molecules are connected into a head-to-tail inversion dimer by a pair of N—H...O hydrogen bonds.

  7. [Teichoic acids from lactic acid bacteria]. (United States)

    Livins'ka, O P; Harmasheva, I L; Kovalenko, N K


    The current view of the structural diversity of teichoic acids and their involvement in the biological activity of lactobacilli has been reviewed. The mechanisms of effects of probiotic lactic acid bacteria, in particular adhesive and immunostimulating functions have been described. The prospects of the use of structure data of teichoic acid in the assessment of intraspecific diversity of lactic acid bacteria have been also reflected.

  8. Uric acid test (image) (United States)

    Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... for testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

  9. Uric acid - urine (United States)

    ... this page: // Uric acid urine test To use the sharing features on this page, please enable JavaScript. The uric acid urine test measures the level of uric acid ...

  10. Methylmalonic acid blood test (United States)

    ... page: // Methylmalonic acid blood test To use the sharing features on this page, please enable JavaScript. The methylmalonic acid blood test measures the amount of methylmalonic acid ...

  11. Plasma amino acids (United States)

    Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

  12. synthesis and characterisation of quinoline functionalised

    African Journals Online (AJOL)


    catalysed C-C coupling reactions. Recently, research efforts have also been devoted to the synthesis of polydentate ligands based on NHC. Specifically, the combination of pyridine and NHC functionalities attracts a considerable amount of interest. ((Danopoulos et al. 2003). The ease of synthesis of imidazolium salts is one ...

  13. Acid distribution in phosphoric acid fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Okae, I.; Seya, A.; Umemoto, M. [Fuji Electric Co., Ltd., Chiba (Japan)


    Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

  14. Spectroscopic quantification of 5-hydroxymethylcytosine in genomic DNA using boric acid-functionalized nano-microsphere fluorescent probes. (United States)

    Chen, Hua-Yan; Wei, Jing-Ru; Pan, Jiong-Xiu; Zhang, Wei; Dang, Fu-Quan; Zhang, Zhi-Qi; Zhang, Jing


    5-hydroxymethylcytosine (5hmC) is the sixth base of DNA. It is involved in active DNA demethylation and can be a marker of diseases such as cancer. In this study, we developed a simple and sensitive 2-(4-boronophenyl)quinoline-4-carboxylic acid modified poly (glycidyl methacrylate (PBAQA-PGMA) fluorescent probe to detect the 5hmC content of genomic DNA based on T4 β-glucosyltransferase-catalyzed glucosylation of 5hmC. The fluorescence-enhanced intensity recorded from the DNA sample was proportional to its 5-hydroxymethylcytosine content and could be quantified by fluorescence spectrophotometry. The developed probe showed good detection sensitivity and selectivity and a good linear relationship between the fluorescence intensity and the concentration of 5 hmC within a 0-100nM range. Compared with other fluorescence detection methods, this method not only could determine trace amounts of 5 hmC from genomic DNA but also could eliminate the interference of fluorescent dyes and the need for purification. It also could avoid multiple labeling. Because the PBAQA-PGMA probe could enrich the content of glycosyl-5-hydroxymethyl-2-deoxycytidine from a complex ground substance, it will broaden the linear detection range and improve sensitivity. The limit of detection was calculated to be 0.167nM after enrichment. Furthermore, the method was successfully used to detect 5-hydroxymethylcytosine from mouse tissues. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Preparation of Chemicals and Bulk Drug Substances for the U.S. Army Drug Development Program

    National Research Council Canada - National Science Library

    Blumbergs, Peter


    .... Types of compounds delivered include substituted quinolines, pyridines, oxazolidines, N-arylpropenamides, carboxylic acids, disulfides, sulfones, thiols and thiol ethers, benzimidazoles, benzoxazoles...

  16. Cell line selection combined with jasmonic acid elicitation enhance camptothecin production in cell suspension cultures of Ophiorrhiza mungos L. (United States)

    Deepthi, S; Satheeshkumar, K


    Ophiorrhiza mungos is a herbaceous medicinal plant which contains a quinoline alkaloid, camptothecin (CPT), an anticancer compound. A high-yielding cell line, O. mungos cell line-3 (OMC3) was selected from cell suspension cultures of O. mungos using cell aggregate cloning method and established cell suspension culture. OMC3 cell suspension produced significantly high biomass (9.25 ± 1.3 g/flask fresh weight (FW)) and CPT yield (0.095 ± 0.002 mg g(-1) dry weight (DW)) compared with the original cell suspension. Inoculum size of OMC3 cell suspension culture was optimised as 14 g L(-1). Media optimisation has shown that 5 % (w/v) sucrose and an increased ammonium/nitrate concentration of 40/20 mM favoured CPT production, whereas 3 % (w/v) sucrose, an ammonium/nitrate concentration of 20/40 mM and 1.25 mM of phosphate favoured biomass accumulation. Jasmonic acid, chitin and salicylic acid was used to elicit CPT production in the original cell suspension culture and achieved significantly high CPT production with jasmonic acid (JA) elicitation. Further, OMC3 cell suspension culture was elicited with JA (50 μM) and obtained 1.12 ± 0.08 mg g(-1) DW CPT and 9.52 ± 1.4 g/flask FW (190.4 g L(-1) FW). The combination of cell line selection and elicitation has produced 18.66-fold increases in CPT production together with significantly high biomass yield. The study is helpful in the scale-up studies of O. mungos cell suspension culture in suitable bioreactor systems for the production of CPT.

  17. Acid Thunder: Acid Rain and Ancient Mesoamerica (United States)

    Kahl, Jonathan D. W.; Berg, Craig A.


    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  18. Krebs cycle intermediates modulate thiobarbituric acid reactive species (TBARS) production in rat brain in vitro. (United States)

    Puntel, Robson L; Nogueira, Cristina W; Rocha, João B T


    The aim of this study was to investigate the effect of Krebs cycle intermediates on basal and quinolinic acid (QA)- or iron-induced TBARS production in brain membranes. Oxaloacetate, citrate, succinate and malate reduced significantly the basal and QA-induced TBARS production. The potency for basal TBARS inhibition was in the order (IC50 is given in parenthesis as mM) citrate (0.37) > oxaloacetate (1.33) = succinate (1.91) > > malate (12.74). alpha-Ketoglutarate caused an increase in TBARS production without modifying the QA-induced TBARS production. Cyanide (CN-) did not modify the basal or QA-induced TBARS production; however, CN- abolished the antioxidant effects of succinate. QA-induced TBARS production was enhanced by iron ions, and abolished by desferrioxamine (DFO). The intermediates used in this study, except for alpha-ketoglutarate, prevented iron-induced TBARS production. Oxaloacetate, citrate, alpha-ketoglutarate and malate, but no succinate and QA, exhibited significantly iron-chelating properties. Only alpha-ketoglutarate and oxaloacetate protected against hydrogen peroxide-induced deoxyribose degradation, while succinate and malate showed a modest effect against Fe2+/H2O2-induced deoxyribose degradation. Using heat-treated preparations citrate, malate and oxaloacetate protected against basal or QA-induced TBARS production, whereas alpha-ketoglutarate induced TBARS production. Succinate did not offer protection against basal or QA-induced TBARS production. These results suggest that oxaloacetate, malate, succinate, and citrate are effective antioxidants against basal and iron or QA-induced TBARS production, while alpha-ketoglutarate stimulates TBARS production. The mechanism through which Krebs cycle intermediates offer protection against TBARS production is distinct depending on the intermediate used. Thus, under pathological conditions such as ischemia, where citrate concentrations vary it can assume an important role as a modulator of oxidative

  19. Discovery of a small molecule that blocks wall teichoic acid biosynthesis in Staphylococcus aureus. (United States)

    Swoboda, Jonathan G; Meredith, Timothy C; Campbell, Jennifer; Brown, Stephanie; Suzuki, Takashi; Bollenbach, Tobias; Malhowski, Amy J; Kishony, Roy; Gilmore, Michael S; Walker, Suzanne


    Both Gram-positive and Gram-negative bacteria contain bactoprenol-dependent biosynthetic pathways expressing non-essential cell surface polysaccharides that function as virulence factors. Although these polymers are not required for bacterial viability in vitro, genes in many of the biosynthetic pathways are conditionally essential: they cannot be deleted except in strains incapable of initiating polymer synthesis. We report a cell-based, pathway-specific strategy to screen for small molecule inhibitors of conditionally essential enzymes. The screen identifies molecules that prevent the growth of a wildtype bacterial strain but do not affect the growth of a mutant strain incapable of initiating polymer synthesis. We have applied this approach to discover inhibitors of wall teichoic acid (WTA) biosynthesis in Staphylococcus aureus. WTAs are anionic cell surface polysaccharides required for host colonization that have been suggested as targets for new antimicrobials. We have identified a small molecule, 7-chloro-N,N-diethyl-3-(phenylsulfonyl)-[1,2,3]triazolo[1,5-a]quinolin-5-amine (1835F03), that inhibits the growth of a panel of S. aureus strains (MIC = 1-3 microg mL(-1)), including clinical methicillin-resistant S. aureus (MRSA) isolates. Using a combination of biochemistry and genetics, we have identified the molecular target as TarG, the transmembrane component of the ABC transporter that exports WTAs to the cell surface. We also show that preventing the completion of WTA biosynthesis once it has been initiated triggers growth arrest. The discovery of 1835F03 validates our chemical genetics strategy for identifying inhibitors of conditionally essential enzymes, and the strategy should be applicable to many other bactoprenol-dependent biosynthetic pathways in the pursuit of novel antibacterials and probes of bacterial stress responses.

  20. Omega-3 Fatty Acids (United States)

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the ... the blood in people with very high triglycerides. Omega-3 fatty acids are in a class of ...

  1. Uric Acid Test (United States)

    ... Links Patient Resources For Health Professionals Subscribe Search Uric Acid Send Us Your Feedback Choose Topic At a ... Also Known As Serum Urate UA Formal Name Uric Acid This article was last reviewed on May 17, ...

  2. Amino Acid Metabolism Disorders (United States)

    ... this process. One group of these disorders is amino acid metabolism disorders. They include phenylketonuria (PKU) and maple syrup urine disease. Amino acids are "building blocks" that join together to form ...

  3. Methylmalonic Acid Test (United States)

    ... Hormone Binding Globulin (SHBG) Shiga toxin-producing Escherichia coli Sickle Cell Tests Sirolimus Smooth Muscle Antibody (SMA) ... Ratio Valproic Acid Vancomycin Vanillylmandelic Acid (VMA) VAP Vitamin A Vitamin B12 and Folate Vitamin D Tests ...

  4. Aminolevulinic Acid Topical (United States)

    Aminolevulinic acid is used in combination with photodynamic therapy (PDT; special blue light) to treat actinic keratoses (small crusty ... skin cancer) of the face or scalp. Aminolevulinic acid is in a class of medications called photosensitizing ...

  5. Acid-fast stain (United States)

    ... this page: // Acid-fast stain To use the sharing features on this page, please enable JavaScript. The acid-fast stain is a laboratory test that determines ...

  6. Valproic Acid and Pregnancy (United States)

    ... questions. We have answers. Fact Sheets Share Valproic Acid and Pregnancy Wednesday, 01 July 2015 In every ... This sheet talks about whether exposure to valproic acid may increase the risk for birth defects over ...

  7. Azelaic Acid Topical (United States)

    Azelaic acid gel and foam is used to clear the bumps, lesions, and swelling caused by rosacea (a skin ... redness, flushing, and pimples on the face). Azelaic acid cream is used to treat the pimples and ...

  8. Zoledronic Acid Injection (United States)

    Zoledronic acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and weak ... of life,' end of regular menstrual periods). Zoledronic acid (Reclast) is also used to treat osteoporosis in ...

  9. Deoxycholic Acid Injection (United States)

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  10. Aminocaproic Acid Injection (United States)

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. ... before the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  11. The Nucleic Acid Database. (United States)

    Berman, Helen M; Westbrook, John; Feng, Zukang; Iype, Lisa; Schneider, Bohdan; Zardecki, Christine


    The Nucleic Acid Database was established in 1991 as a resource to assemble and distribute structural information about nucleic acids. Over the years, the NDB has developed generalized software for processing, archiving, querying and distributing structural data for nucleic acid-containing structures. The architecture and capabilities of the Nucleic Acid Database, as well as some of the research enabled by this resource, are presented in this article.

  12. Immunoglobulin and fatty acids

    DEFF Research Database (Denmark)


    The present invention relates to a composition comprising 0.1-10 w/w % immunoglobulin (Ig), 4-14 w/w % saturated fatty acids, 4-14 w/w % mono-unsaturated fatty acids and 0-5 w/w % poly-unsaturated fatty acids, wherein the weight percentages are based on the content of dry matter in the composition...

  13. Amino acids and proteins

    NARCIS (Netherlands)

    van Goudoever, Johannes B.; Vlaardingerbroek, Hester; van den Akker, Chris H.; de Groof, Femke; van der Schoor, Sophie R. D.


    Amino acids and protein are key factors for growth. The neonatal period requires the highest intake in life to meet the demands. Those demands include amino acids for growth, but proteins and amino acids also function as signalling molecules and function as neurotransmitters. Often the nutritional

  14. Stomach acid test (United States)

    Gastric acid secretion test ... of the cells in the stomach to release acid. The stomach contents are then removed and analyzed. ... 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour (mEq/ ...

  15. The Acid Rain Reader. (United States)

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  16. Acid Rain Study Guide. (United States)

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  17. Demospongic Acids Revisited

    Directory of Open Access Journals (Sweden)

    Gilles Barnathan


    Full Text Available The well-known fatty acids with a D5,9 unsaturation system were designated for a long period as demospongic acids, taking into account that they originally occurred in marine Demospongia sponges. However, such acids have also been observed in various marine sources with a large range of chain-lengths (C16–C32 and from some terrestrial plants with short acyl chains (C18–C19. Finally, the D5,9 fatty acids appear to be a particular type of non-methylene-interrupted fatty acids (NMA FAs. This article reviews the occurrence of these particular fatty acids in marine and terrestrial organisms and shows the biosynthetic connections between D5,9 fatty acids and other NMI FAs.

  18. Boric acid and boronic acids inhibition of pigeonpea urease. (United States)

    Reddy, K Ravi Charan; Kayastha, Arvind M


    Urease from the seeds of pigeonpea was competitively inhibited by boric acid, butylboronic acid, phenylboronic acid, and 4-bromophenylboronic acid; 4-bromophenylboronic acid being the strongest inhibitor, followed by boric acid > butylboronic acid > phenylboronic acid, respectively. Urease inhibition by boric acid is maximal at acidic pH (5.0) and minimal at alkaline pH (10.0), i.e., the trigonal planar B(OH)3 form is a more effective inhibitor than the tetrahedral B(OH)4 -anionic form. Similarly, the anionic form of phenylboronic acid was least inhibiting in nature.

  19. The Sensitivities of Yeast Strains Deficient in PDR ABC Transporters to Quinoline-Ring Antimalarial Drugs (United States)


    the parasite (Fidock etal., 2000; Ursos Infectious Diseases, etal., 2000, 2001). Harvard School of Public Health, Boston, MA 02115, U.S.A...Fidock, D. A., Nomura, T., Talley, A. K., Cooper, & Wolfe, K. H. (1996). Yeast, 12, 999-1004. R- A., Dzekunov, S. M., Ferdig, M. T., Ursos , L. M., Pearce...Holland, B. & Rubartelli, A. pp. 49-85. Austin, TX: Ursos , L. M., DuBay, K. F. & Roepe, P. D. (2001). Landes Bioscience. Molecular and Biochemical

  20. Process for the preparation of lactic acid and glyceric acid (United States)

    Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI


    Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

  1. Microorganisms for producing organic acids

    Energy Technology Data Exchange (ETDEWEB)

    Pfleger, Brian Frederick; Begemann, Matthew Brett


    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  2. Glycolic Acid 15% Plus Salicylic Acid 2% (United States)

    Sánchez-Blanco, Elena


    Background: Facial flat warts are a contagious viral disease that can cause disturbing cosmetic problems. Topical glycolic acid has been reported to be effective in dermatological treatment depending on the exfoliant capacity, but has not often been reported to be effective in the treatment of facial flat warts. Objective: The aim of this paper was to evaluate the efficacy and safety of glycolic acid 15% topical gel plus salicylic acid 2% in the treatment of recalcitrant facial flat warts. Methods: A total of 20 consecutive patients 7 to 16 years of age with recalcitrant facial flat warts were enrolled in this study. Patients having warts by the eye and lip regions were excluded from the study. A fine layer of face gel was applied to the treatment area once daily. Most of the participants had tried different treatments with no success. Assessments for the response and the occurrence of side effects were performed every two weeks at Weeks 2, 4, 6, and 8. Results: All the patients were clinically cured within eight weeks. Seven patients cleared in four weeks, and 13 patients cleared in eight weeks. No noticeable adverse events were related to the skin. Conclusion: Topical gel of glycolic acid 15% plus salicylic acid 2% is safe and effective when applied to facial flat warts once daily until clearance and may be considered as first-line treatment. PMID:21938272

  3. Comparison of the effect of acetic, propionic and butyric acids on ...

    African Journals Online (AJOL)



    May 23, 2011 ... chloride (NaCl), calcium carbonate (CaCO3), vitamin A, vitamin D3, vitamin E and ethoxy quinoline, The dry ... g threonine, 4 g sodium chloride, 15000 IU vitamin A, 2500 IU vitamin D3, 80 IU vitamin E and 10 ... determined using computer-operated MOTIC microscope dmb B5 series picture analysis system ...

  4. Lewis Acid Organocatalysts (United States)

    Sereda, Oksana; Tabassum, Sobia; Wilhelm, René

    The term Lewis acid catalysts generally refers to metal salts like aluminium chloride, titanium chloride and zinc chloride. Their application in asymmetric catalysis can be achieved by the addition of enantiopure ligands to these salts. However, not only metal centers can function as Lewis acids. Compounds containing carbenium, silyl or phosphonium cations display Lewis acid catalytic activity. In addition, hypervalent compounds based on phosphorus and silicon, inherit Lewis acidity. Furthermore, ionic liquids, organic salts with a melting point below 100 °C, have revealed the ability to catalyze a range of reactions either in substoichiometric amount or, if used as the reaction medium, in stoichiometric or even larger quantities. The ionic liquids can often be efficiently recovered. The catalytic activity of the ionic liquid is explained by the Lewis acidic nature of their cations. This review covers the survey of known classes of metal-free Lewis acids and their application in catalysis.

  5. Citric Acid Alternative to Nitric Acid Passivation (United States)

    Lewis, Pattie L. (Compiler)


    The Ground Systems Development and Operations GSDO) Program at NASA John F. Kennedy Space Center (KSC) has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of the GSDO Program, the purpose of this project is to demonstratevalidate citric acid as a passivation agent for stainless steel. Successful completion of this project will result in citric acid being qualified for use as an environmentally preferable alternative to nitric acid for passivation of stainless steel alloys in NASA and DoD applications.

  6. Facts about Folic Acid (United States)

    ... to Other Health Outcomes Folic Acid Fortification and Supplementation Neural Tube Defects Surveillance References Data and Statistics Research Birth Defects COUNT Articles & Key Findings Recommendations Links to ...

  7. Folic Acid Quiz (United States)

    ... to Other Health Outcomes Folic Acid Fortification and Supplementation Neural Tube Defects Surveillance References Data and Statistics Research Birth Defects COUNT Articles & Key Findings Recommendations Links to ...

  8. USGS Tracks Acid Rain (United States)

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.


    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  9. Parenteral Nutrition: Amino Acids. (United States)

    Hoffer, Leonard John


    There is growing interest in nutrition therapies that deliver a generous amount of protein, but not a toxic amount of energy, to protein-catabolic critically ill patients. Parenteral amino acids can achieve this goal. This article summarizes the biochemical and nutritional principles that guide parenteral amino acid therapy, explains how parenteral amino acid solutions are formulated, and compares the advantages and disadvantages of different parenteral amino acid products with enterally-delivered whole protein products in the context of protein-catabolic critical illness.

  10. Fusidic acid in dermatology

    DEFF Research Database (Denmark)

    Schöfer, Helmut; Simonsen, Lene


    Studies on the clinical efficacy of fusidic acid in skin and soft-tissue infections (SSTIs), notably those due to Staphylococcus aureus, are reviewed. Oral fusidic acid (tablets dosed at 250 mg twice daily, or a suspension for paediatric use at 20 mg/kg/day given as two daily doses) has shown good...... efficacy and tolerability. Similarly, plain fusidic acid cream or ointment used two or three times daily in SSTIs such as impetigo are clinically and bacteriologically effective, with minimal adverse events. Combination formulations of fusidic acid with 1% hydrocortisone or 0.1% betamethasone achieve...

  11. Azetidinic amino acids

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Bunch, Lennart; Chopin, Nathalie


    A set of ten azetidinic amino acids, that can be envisioned as C-4 alkyl substituted analogues of trans-2-carboxyazetidine-3-acetic acid (t-CAA) and/or conformationally constrained analogues of (R)- or (S)-glutamic acid (Glu) have been synthesized in a diastereo- and enantiomerically pure form from...... of two diastereoisomers that were easily separated and converted in two steps into azetidinic amino acids. Azetidines 35-44 were characterized in binding studies on native ionotropic Glu receptors and in functional assays at cloned metabotropic receptors mGluR1, 2 and 4, representing group I, II and III...

  12. Peptide Nucleic Acids

    DEFF Research Database (Denmark)


    A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

  13. Peptide Nucleic Acids (PNA)

    DEFF Research Database (Denmark)


    A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

  14. Peptide Nucleic Acids

    DEFF Research Database (Denmark)


    A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

  15. Locked nucleic acid

    DEFF Research Database (Denmark)

    Jepsen, Jan Stenvang; Sørensen, Mads D; Wengel, Jesper


    Locked nucleic acid (LNA) is a class of nucleic acid analogs possessing very high affinity and excellent specificity toward complementary DNA and RNA, and LNA oligonucleotides have been applied as antisense molecules both in vitro and in vivo. In this review, we briefly describe the basic physioc...

  16. Amino Acid Crossword Puzzle (United States)

    Sims, Paul A.


    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  17. Peptide Nucleic Acid Synthons

    DEFF Research Database (Denmark)


    A novel class of compounds, known as peptide nucleic acids, bind complementary ssDNA and RNA strands more strongly than a corresponding DNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....

  18. Salicylic Acid Topical (United States)

    ... product less often. Talk to your doctor or check the package label for more information.Apply a small amount of the salicylic acid product ... in salicylic acid products. Ask your pharmacist or check the package label for a list of the not apply any of the following products to the skin ...

  19. Chlorogenic acid and caffeic acid are absorbed in humans

    NARCIS (Netherlands)

    Olthof, M.R.; Hollman, P.C.H.; Katan, M.B.


    Chlorogenic acid, an ester of caffeic acid and quinic acid, is a major phenolic compound in coffee; daily intake in coffee drinkers is 0.5-1 g. Chlorogenic acid and caffeic acid are antioxidants in vitro and might therefore contribute to the prevention of cardiovascular disease. However, data on the

  20. 2-Methylaspartic acid monohydrate

    Directory of Open Access Journals (Sweden)

    Ray J. Butcher


    Full Text Available The title compound, C5H9NO4·H2O, is an isomer of the α-amino acid glutamic acid that crystallizes from water in its zwitterionic form as a monohydrate. It is not one of the 20 proteinogenic α-amino acids that are used in living systems and differs from the natural amino acids in that it has an α-methyl group rather than an α-H atom. In the crystal, an O—H...O hydrogen bond is present between the acid and water molecules while extensive N—H...O and O—H...O hydrogen bonds link the components into a three-dimensional array.

  1. Degradation Network Reconstruction in Uric Acid and Ammonium Amendments in Oil-Degrading Marine Microcosms Guided by Metagenomic Data

    KAUST Repository

    Bargiela, Rafael


    Biostimulation with different nitrogen sources is often regarded as a strategy of choice in combating oil spills in marine environments. Such environments are typically depleted in nitrogen, therefore limiting the balanced microbial utilization of carbon-rich petroleum constituents. It is fundamental, yet only scarcely accounted for, to analyze the catabolic consequences of application of biostimulants. Here, we examined such alterations in enrichment microcosms using sediments from chronically crude oil-contaminated marine sediment at Ancona harbor (Italy) amended with natural fertilizer, uric acid (UA), or ammonium (AMM). We applied the web-based AromaDeg resource using as query Illumina HiSeq meta-sequences (UA: 27,893 open reading frames; AMM: 32,180) to identify potential catabolic differences. A total of 45 (for UA) and 65 (AMM) gene sequences encoding key catabolic enzymes matched AromaDeg, and their participation in aromatic degradation reactions could be unambiguously suggested. Genomic signatures for the degradation of aromatics such as 2-chlorobenzoate, indole-3-acetate, biphenyl, gentisate, quinoline and phenanthrene were common for both microcosms. However, those for the degradation of orcinol, ibuprofen, phenylpropionate, homoprotocatechuate and benzene (in UA) and 4-aminobenzene-sulfonate, p-cumate, dibenzofuran and phthalate (in AMM), were selectively enriched. Experimental validation was conducted and good agreement with predictions was observed. This suggests certain discrepancies in action of these biostimulants on the genomic content of the initial microbial community for the catabolism of petroleum constituents or aromatics pollutants. In both cases, the emerging microbial communities were phylogenetically highly similar and were composed by very same proteobacterial families. However, examination of taxonomic assignments further revealed different catabolic pathway organization at the organismal level, which should be considered for designing

  2. Degradation network reconstruction in uric acid and ammonium amendments in oil-degrading marine microcosms guided by metagenomic data

    Directory of Open Access Journals (Sweden)

    Rafael eBargiela


    Full Text Available Biostimulation with different nitrogen sources is often regarded as a strategy of choice in combating oil spills in marine environments. Such environments are typically depleted in nitrogen, therefore limiting the balanced microbial utilization of carbon-rich petroleum constituents. It is fundamental, yet only scarcely accounted for, to analyse the catabolic consequences of application of biostimulants. Here, we examined such alterations in enrichment microcosms using sediments from chronically crude oil-contaminated marine sediment at Ancona harbor (Italy amended with natural fertilizer, uric acid (UA, or ammonium (AMM. We applied the web-based AromaDeg resource using as query Illumina HiSeq meta-sequences (UA: 27,893 open reading frames; AMM: 32,180 to identify potential catabolic differences. A total of 45 (for UA and 65 (AMM gene sequences encoding key catabolic enzymes matched AromaDeg, and their participation in aromatic degradation reactions could be unambiguously suggested. Genomic signatures for the degradation of aromatics such as 2-chlorobenzoate, indole-3-acetate, biphenyl, gentisate, quinoline and phenanthrene were common for both microcosms. However, those for the degradation of orcinol, ibuprofen, phenylpropionate, homoprotocatechuate and benzene (in UA and 4-aminobenzene-sulfonate, p-cumate, dibenzofuran and phthalate (in AMM, were selectively enriched. Experimental validation was conducted and good agreement with predictions was observed. This suggests certain discrepancies in action of these biostimulants on the genomic content of the initial microbial community for the catabolism of petroleum constituents or aromatics pollutants. In both cases, the emerging microbial communities were phylogenetically highly similar and were composed by very same proteobacterial families. However, examination of taxonomic assignments further revealed different catabolic pathway organization at the organismal level, which should be considered

  3. Trans Fatty Acids (United States)

    Doyle, Ellin


    Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.


    DEFF Research Database (Denmark)


    An isolated glycosyltransferase (GT) polypeptide capable of: (I): conjugating glucose to flavokermesic acid (FK); and/or (II): conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid.......An isolated glycosyltransferase (GT) polypeptide capable of: (I): conjugating glucose to flavokermesic acid (FK); and/or (II): conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid....

  5. Citric acid production. (United States)

    Berovic, Marin; Legisa, Matic


    Citric acid is a commodity chemical produced and consumed throughout The World. It is used mainly in the food and beverage industry, primarily as an acidulant. Although it is one of the oldest industrial fermentations, its World production is still in rapid increasing. Global production of citric acid in 2007 was over 1.6 million tones. Biochemistry of citric acid fermentation, various microbial strains, as well as various substrates, technological processes and product recovery are presented. World production and economics aspects of this strategically product of bulk biotechnology are discussed.

  6. Halogenated fatty acids

    DEFF Research Database (Denmark)

    Mu, Huiling; Wesén, Clas; Sundin, Peter


    , chlorinated lipids have been found in meat exposed to hypochlorite disinfected water, and in chlorine-treated flour and in products made from such flour. Following exposure to chlorine bleached pulp mill effluents, aquatic organisms may have elevated concentrations of chlorinated fatty acids in their lipids....... However, a natural production of halogenated fatty acids is also possible. In this paper we summarize the present knowledge of the occurrence of halogenated fatty acids in lipids and suggested ways of their formation. In Part II (Trends Anal. Chem. 16 (1997) 274) we deal with methods...

  7. Bile acid sequestrants

    DEFF Research Database (Denmark)

    Hansen, Morten; Sonne, David P; Knop, Filip K


    Bile acids are synthesized in the liver from cholesterol and have traditionally been recognized for their role in absorption of lipids and in cholesterol homeostasis. In recent years, however, bile acids have emerged as metabolic signaling molecules that are involved in the regulation of lipid...... of the enterohepatic circulation. This increases bile acid synthesis and consequently reduces serum low-density lipoprotein cholesterol. Also, BASs improve glycemic control in patients with type 2 diabetes. Despite a growing understanding of the impact of BASs on glucose metabolism, the mechanisms behind their glucose...

  8. Pharmacologically significant complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) of novel Schiff base ligand, (E)-N-(furan-2-yl methylene) quinolin-8-amine: Synthesis, spectral, XRD, SEM, antimicrobial, antioxidant and in vitro cytotoxic studies (United States)

    Shakir, M.; Hanif, Summaiya; Sherwani, Mohd. Asif; Mohammad, Owais; Al-Resayes, Saud I.


    A novel series of metal complexes of the types, [ML2(H2O)2]Cl2 and [ML2]Cl2 [M = Mn(II), 1; Co(II), 2; Ni(II), 3; Cu(II), 4; and Zn(II), 5] were synthesized by the interaction of ligand, L (E)-N-(furan-2-yl methylene) quinolin-8-amine, derived from the condensation of 2-furaldehyde and 8-aminoquinoline. The synthesized ligand and its metal complexes were characterized on the basis of results obtained from elemental analysis, ESI-MS, XRD, SEM, TGA/DTA, FT-IR, UV-Vis, magnetic moment and 1H and 13C NMR spectroscopic studies. EPR parameters were recorded in case of complex 4. The comparative in-vitro antimicrobial activities against various pathogens with reference to known antibiotics and antioxidant activity against standard control at variable concentrations revealed that the metal complexes show enhanced antimicrobial and free radical scavenging activities in general as compared to free ligand. However, the complexes 1 and 5 have shown best antioxidant activity among all the metal complexes. Furthermore, comparative in-vitro antiproliferative activity on ligand and its metal chelates performed on MDA-MB-231 (breast carcinoma), KCL22 (blood lymphoid carcinoma), HeLa (cervical carcinoma) cell lines and normal cells (PBMC) revealed that metal chelates show moderate to good activity as compared to ligand where as complex 1 seems to be the most promising one possessing a broad spectrum of activity against all the selected cancer cell lines with IC50 < 2.10 μM.

  9. Synthesis, molecular, electronic structure, linear and non-linear optical and phototransient properties of 8-methyl-1,2-dihydro-4H-chromeno[2,3-b]quinoline-4,6(3H)-dione (MDCQD): Experimental and DFT investigations (United States)

    Farag, A. A. M.; Roushdy, N.; Halim, Shimaa Abdel; El-Gohary, Nasser M.; Ibrahim, Magdy A.; Said, Sara


    Base catalysed ring opening ring closure (RORC) reaction of 6-methylchromone-3‑carbonitrile (1) with 1,3-cyclohexanedione afforded 8-methyl-1,2-dihydro-4H-chromeno[2,3-b]quinoline-4,6(3H)-dione (MDCQD). Theoretical calculations by Density Functional Theory (DFT) at the B3LYP/6-311G (d,p) level of theory was utilized to illustrate the equilibrium geometries of MDCQD. Also, the nonlinear optical properties, simple harmonic vibrational frequencies, thermo-chemical parameters and Mullikan atomic charges were calculated. In addition, the electronic absorption spectra in polar and non polar solvents were discussed on the basis of TD-DFT calculations. A nanofiber-like structure with high aggregation was resolved by using scanning electron microscopy images and its particle sizes were measured by particle size analyzer. The spectroscopic characteristics of the prepared thin film of MDCQD were studied in a wide spectral range of 200-2500 nm. The analysis of the absorption edges affords two direct optical band gaps with energies of 1.00 and 2.76 eV. A characteristic emission peak of photoluminescence spectrum in the visible region was detected and has a red-shift as a result of solvent polarity. The MDCQD film based heterojunction showed rectification behavior and diode-like characteristics. The photovoltaic characteristics under illumination of 100 mW/cm2 were studied. The open-circuit voltage and short-circuit current were found to be 0.22 V and 4.25 × 10- 7 A/cm2, respectively. Moreover, the prepared heterojunction showed remarkable phototransient characteristics which afford the probability for the operation as a photodiode.

  10. Acid Lipase Disease (United States)

    ... offers free searches of biomedical literature through an Internet service called PubMed. To search, go to: . The NLM also offers extensive ... Publications Definition Acid ...

  11. Acid rain: An overview (United States)

    US Fish and Wildlife Service, Department of the Interior — Summary of the effects of acid rain and related processes, sources, issues, corrective actions, research, current law, potential solutions, political solutions,...

  12. Boric acid poisoning (United States)

    ... Skin lotions Some paints Some rodent and ant pesticides Photography chemicals Powders to kill roaches Some eye ... 1031. National Library of Medicine, Specialized Information Services, Toxicology Data Network. Boric acid. ...

  13. Alpha Hydroxy Acids (United States)

    ... sensitivity. FDA also has collaborated with the National Toxicology Program (NTP) to assess the safety of the long-term use of AHAs. This study determined that glycolic acid did not affect photocarcinogenesis ( ...

  14. Folic acid in diet (United States)

    ... Pregnant females of all ages: 600 mcg/day Breastfeeding females of all ages: 500 mcg/day Alternative Names Folic acid; Polyglutamyl folacin; Pteroylmonoglutamate; Folate Images Vitamin B9 benefits Vitamin B9 source References Institute of Medicine, Food ...

  15. Lipoic Acid Synthase (LASY)

    National Research Council Canada - National Science Library

    Indira Padmalayam; Sumera Hasham; Uday Saxena; Sivaram Pillarisetti


    Lipoic Acid Synthase (LASY) A Novel Role in Inflammation, Mitochondrial Function, and Insulin Resistance Indira Padmalayam 1 , Sumera Hasham 2 , Uday Saxena 1 and Sivaram Pillarisetti 1 1 Discovery Research, ReddyUS...

  16. Synthesis of aminoaldonic acids

    DEFF Research Database (Denmark)

    Jørgensen, Christel Thea

    of 2,5-anhydrides and not the expected 2-acetamido-2-deoxy aldose phenylhydrazones. The acetylated phenylhydrazones were found to eliminate acetic acid when heated in aqueous ethanol and 1-phenylazoalkenes could be isolated by crystallisation. By this method the 17, 20, 23 and 25 were prepared from....... The aziridino amides 43 and 51 were reductively cleaved with hydrazine to give 3-amino-2,3-dideoxyhexonhydrazides 83 and 85, which were easily converted into the corresponding lactone 84 and acid 86. The aziridine ring of 43 and 51 was also opened with acetic acid to give the 3-amino-3-deoxyhexonic acids 79....... These compounds did not react with 2-(3,4-dimethoxyphenyl)ethyl amine 105. Instead the commercially available unsubstituted 4-carboxyl tetronolactone 108 was converted into the 2-(3,4-dimethoxyphenyl)ethyl amides 110 and 111 in two steps. These amides were cyclised by the Bischler-Napieralski cyclisation to give...

  17. Amino Acids and Chirality (United States)

    Cook, Jamie E.


    Amino acids are among the most heavily studied organic compound class in carbonaceous chondrites. The abundance, distributions, enantiomeric compositions, and stable isotopic ratios of amino acids have been determined in carbonaceous chondrites fi'om a range of classes and petrographic types, with interesting correlations observed between these properties and the class and typc of the chondritcs. In particular, isomeric distributions appear to correlate with parent bodies (chondrite class). In addition, certain chiral amino acids are found in enantiomeric excess in some chondrites. The delivery of these enantiomeric excesses to the early Earth may have contributed to the origin of the homochirality that is central to life on Earth today. This talk will explore the amino acids in carbonaceous chondritcs and their relevance to the origin of life.

  18. Peptide Nucleic Acids

    DEFF Research Database (Denmark)


    A novel class of compounds known as peptide nucleic acids, bind complementary DNA and RNA strands, and generally do so more strongly than the corresponding DNA or RNA strands while exhibiting increased sequence specificity and solubility. The peptide nucleic acids comprise ligands selected from a...... a group consisting of naturally-occurring nucleobases and non-naturally-occurring nucleobases, including 2,6-diaminopurine, attached to a polyamide backbone, and contain alkyl amine side chains....

  19. Folic acid in pregnancy

    National Research Council Canada - National Science Library

    Paul, Carolyn


    ... it was isolated from spinach in 1941, hence being named ‘folic acid’ (from the Latin word folium for leaf ). By the mid‐1940s a team of biochemists, ‘the folic acid boys’, working at the Lederle Laboratory in Pearl River, New York, USA were able to synthesise folic acid in a pure crystalline form, allowing more detailed evaluation of its properties. I...

  20. Methyl 7,8-diacetoxy-11-oxo-5-(2-oxopyrrolidin-1-yl-7,9-epoxycyclopenta[4,5]pyrido[1,2-a]quinoline-10-carboxylate sesquihydrate

    Directory of Open Access Journals (Sweden)

    Atash V. Gurbanov


    Full Text Available The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water molecules occupying a special position on a twofold axis. The organic molecule comprises a fused pentacyclic system containing two five-membered rings (cyclopentane and tetrahydrofuran and three six-membered rings (piperidinone, tetrahydropyridine and benzene. The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetrahydropyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H...O hydrogen bonds, which link the organic molecules and water molecules into complex two-tier layers parallel to (001. The layers are further linked into a three-dimensional framework by attractive intermolecular carbonyl–carbonyl interactions.

  1. Fatty Acid Biosynthesis IX

    DEFF Research Database (Denmark)

    Carey, E. M.; Hansen, Heinz Johs. Max; Dils, R.


    # 1. I. [I-14C]Acetate was covalently bound to rabbit mammary gland fatty acid synthetase by enzymic transacylation from [I-14C]acetyl-CoA. Per mole of enzyme 2 moles of acetate were bound to thiol groups and up to I mole of acetate was bound to non-thiol groups. # 2. 2. The acetyl-fatty acid...... synthetase complex was isolated free from acetyl-CoA. It was rapidly hydrolysed at 30°C, but hydrolysis was greatly diminished at o°C and triacetic lactone synthesis occurred. In the presence of malonyl-CoA and NADPH, all the acetate bound to fatty acid synthetase was incorporated into long-chain fatty acids....... Hydrolysis of bound acetate and incorporation of bound acetate into fatty acids were inhibited to the same extent by guanidine hydrochloride. # 3. 3. Acetate was also covalently bound to fatty acid synthetase by chemical acetylation with [I-14C]acetic anhydride in the absence of CoASH. A total of 60 moles...

  2. Combining structure-based pharmacophore modeling, virtual screening, and in silico ADMET analysis to discover novel tetrahydro-quinoline based pyruvate kinase isozyme M2 activators with antitumor activity

    Directory of Open Access Journals (Sweden)

    Chen C


    Full Text Available Can Chen,1,2,* Ting Wang,1,3,* Fengbo Wu,1,* Wei Huang,4 Gu He,1 Liang Ouyang,1 Mingli Xiang,1 Cheng Peng,4 Qinglin Jiang1,2 1State Key Laboratory of Biotherapy and Department of Pharmacy, West China Hospital, Sichuan University, Chengdu, 2College of Pharmacy and the First Affiliated Hospital, Chengdu Medical College, Chengdu, 3Department of Cardiology, Genenal Hospital of Chengdu Military Command, Chengdu, 4State Key Laboratory Breeding Base of Systematic Research, Development and Utilization of Chinese Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, People’s Republic of China*These authors contributed equally to this workAbstract: Compared with normal differentiated cells, cancer cells upregulate the expression of pyruvate kinase isozyme M2 (PKM2 to support glycolytic intermediates for anabolic processes, including the synthesis of nucleic acids, amino acids, and lipids. In this study, a combination of the structure-based pharmacophore modeling and a hybrid protocol of virtual screening methods comprised of pharmacophore model-based virtual screening, docking-based virtual screening, and in silico ADMET (absorption, distribution, metabolism, excretion and toxicity analysis were used to retrieve novel PKM2 activators from commercially available chemical databases. Tetrahydroquinoline derivatives were identified as potential scaffolds of PKM2 activators. Thus, the hybrid virtual screening approach was applied to screen the focused tetrahydroquinoline derivatives embedded in the ZINC database. Six hit compounds were selected from the final hits and experimental studies were then performed. Compound 8 displayed a potent inhibitory effect on human lung cancer cells. Following treatment with Compound 8, cell viability, apoptosis, and reactive oxygen species (ROS production were examined in A549 cells. Finally, we evaluated the effects of Compound 8 on mice xenograft tumor models in vivo. These results may provide important

  3. Acidification and Acid Rain (United States)

    Norton, S. A.; Veselã½, J.


    Air pollution by acids has been known as a problem for centuries (Ducros, 1845; Smith, 1872; Camuffo, 1992; Brimblecombe, 1992). Only in the mid-1900s did it become clear that it was a problem for more than just industrially developed areas, and that precipitation quality can affect aquatic resources ( Gorham, 1955). The last three decades of the twentieth century saw tremendous progress in the documentation of the chemistry of the atmosphere, precipitation, and the systems impacted by acid atmospheric deposition. Chronic acidification of ecosystems results in chemical changes to soil and to surface waters and groundwater as a result of reduction of base cation supply or an increase in acid (H+) supply, or both. The most fundamental changes during chronic acidification are an increase in exchangeable H+ or Al3+ (aluminum) in soils, an increase in H+ activity (˜concentration) in water in contact with soil, and a decrease in alkalinity in waters draining watersheds. Water draining from the soil is acidified and has a lower pH (=-log [H+]). As systems acidify, their biotic community changes.Acidic surface waters occur in many parts of the world as a consequence of natural processes and also due to atmospheric deposition of strong acid (e.g., Canada, Jeffries et al. (1986); the United Kingdom, Evans and Monteith (2001); Sweden, Swedish Environmental Protection Board (1986); Finland, Forsius et al. (1990); Norway, Henriksen et al. (1988a); and the United States (USA), Brakke et al. (1988)). Concern over acidification in the temperate regions of the northern hemisphere has been driven by the potential for accelerating natural acidification by pollution of the atmosphere with acidic or acidifying compounds. Atmospheric pollution ( Figure 1) has resulted in an increased flux of acid to and through ecosystems. Depending on the ability of an ecosystem to neutralize the increased flux of acidity, acidification may increase only imperceptibly or be accelerated at a rate that

  4. Differential activation of pregnane X receptor by carnosic acid, carnosol, ursolic acid, and rosmarinic acid. (United States)

    Seow, Chun Ling; Lau, Aik Jiang


    Pregnane X receptor (PXR) regulates the expression of many genes, including those involved in drug metabolism and transport, and has been linked to various diseases, including inflammatory bowel disease. In the present study, we determined whether carnosic acid and other chemicals in rosemary extract (carnosol, ursolic acid, and rosmarinic acid) are PXR activators. As assessed in dual-luciferase reporter gene assays, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, activated human PXR (hPXR) and mouse PXR (mPXR), whereas carnosol and ursolic acid, but not carnosic acid or rosmarinic acid, activated rat PXR (rPXR). Dose-response experiments indicated that carnosic acid, carnosol, and ursolic acid activated hPXR with EC50 values of 0.79, 2.22, and 10.77μM, respectively. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, transactivated the ligand-binding domain of hPXR and recruited steroid receptor coactivator-1 (SRC-1), SRC-2, and SRC-3 to the ligand-binding domain of hPXR. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, increased hPXR target gene expression, as shown by an increase in CYP3A4, UGT1A3, and ABCB1 mRNA expression in LS180 human colon adenocarcinoma cells. Rosmarinic acid did not attenuate the extent of hPXR activation by rifampicin, suggesting it is not an antagonist of hPXR. Overall, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, are hPXR agonists, and carnosic acid shows species-dependent activation of hPXR and mPXR, but not rPXR. The findings provide new mechanistic insight on the effects of carnosic acid, carnosol, and ursolic acid on PXR-mediated biological effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Cytotoxic effect of betulinic acid and betulinic acid acetate isolated ...

    African Journals Online (AJOL)



    Sep 20, 2010 ... Key words: Betulinic acid, HL 60, cytotoxicity, MTT assay, DNA laddering, Cell cycle PI. INTRODUCTION. Betulinic acid ... Chemical structure of betulinic acid and its derivatives. (Fulda et al., 1999) and leukemia cells ... feature makes betulinic acid unique in comparison to compounds that are currently used ...

  6. [Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis]. (United States)

    Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua


    Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

  7. Synthesis and anticonvulsant activity of novel bicyclic acidic amino acids

    DEFF Research Database (Denmark)

    Conti, Paola; De Amici, Marco; Joppolo Di Ventimiglia, Samuele


    Bicyclic acidic amino acids (+/-)-6 and (+/-)-7, which are conformationally constrained homologues of glutamic acid, were prepared via a strategy based on a 1,3-dipolar cycloaddition. The new amino acids were tested toward ionotropic and metabotropic glutamate receptor subtypes; both of them...

  8. Amino acids in the sedimentary humic and fulvic acids

    Digital Repository Service at National Institute of Oceanography (India)

    Sardessai, S.

    Humic and fulvic acids isolated from a few sediment samples from Arabian Sea and Bay of Bengal were analysed for total hydrolysable amino acids concentration and their composition. The amono acids content of fulvic acids was higher than in the humic...

  9. Amino-acid contamination of aqueous hydrochloric acid. (United States)

    Wolman, Y.; Miller, S. L.


    Considerable amino-acid contamination in commercially available analytical grade hydrochloric acid (37% HCl) was found. One bottle contained 8,300 nmol of amino-acids per liter. A bottle from another supplier contained 6,700 nmol per liter. The contaminants were mostly protein amino-acids and several unknowns. Data on the volatility of the amino-acids during HCl distillation were also obtained.

  10. Analysis of Bile Acids (United States)

    Sjövall, Jan; Griffiths, William J.; Setchell, Kenneth D. R.; Mano, Nariyasu; Goto, Junichi

    Bile acids constitute a large family of steroids in vertebrates, normally formed from cholesterol and carrying a carboxyl group in a side-chain of variable length. Bile alcohols, also formed from cholesterol, have similar structures as bile acids, except for the absence of a carboxyl group in the steroid skeleton. The conversion of cholesterol to bile acids and/or bile alcohols is of major importance for maintenance of cholesterol homeostasis, both from quantitative and regulatory points of view (Chiang, 2004; Kalaany and Mangelsdorf, 2006; Moore, Kato, Xie, et al., 2006; Scotti, Gilardi, Godio, et al., 2007). Appropriately conjugated bile acids and bile alcohols (also referred to as bile salts) are secreted in bile and serve vital functions in the absorption of lipids and lipid-soluble compounds (Hofmann, 2007). Reliable analytical methods are required for studies of the functions and pathophysiological importance of the variety of bile acids and bile alcohols present in living organisms. When combined with genetic and proteomic studies, analysis of these small molecules (in today's terminology: metabolomics, steroidomics, sterolomics, cholanoidomics, etc.) will lead to a deeper understanding of the integrated metabolic processes in lipid metabolism.

  11. Unexpected effects of peripherally administered kynurenic acid on cortical spreading depression and related blood–brain barrier permeability

    Directory of Open Access Journals (Sweden)

    Oláh G


    Full Text Available Gáspár Oláh,1 Judit Herédi,1 Ákos Menyhárt,1 Zsolt Czinege,2 Dávid Nagy,1 János Fuzik,1 Kitti Kocsis,1 Levente Knapp,1 Erika Krucsó,1 Levente Gellért,1 Zsolt Kis,1 Tamás Farkas,1 Ferenc Fülöp,3 Árpád Párdutz,4 János Tajti,4 László Vécsei,4 József Toldi1 1Department of Physiology, Anatomy and Neuroscience, 2Department of Software Engineering, 3Institute of Pharmaceutical Chemistry and MTA-SZTE Research Group for Stereochemistry, 4Department of Neurology and MTA-SZTE Neuroscience Research Group, University of Szeged, Szeged, Hungary Abstract: Cortical spreading depression (CSD involves a slowly-propagating depolarization wave in the cortex, which can appear in numerous pathophysiological conditions, such as migraine with aura, stroke, and traumatic brain injury. Neurons and glial cells are also depolarized transiently during the phenomena. CSD is followed by a massive increase in glutamate release and by changes in the brain microcirculation. The aim of this study was to investigate the effects of two N-methyl-D-aspartate receptor antagonists, endogenous kynurenic acid (KYNA and dizocilpine, on CSD and the related blood–brain barrier (BBB permeability in rats. In intact animals, KYNA hardly crosses the BBB but has some positive features as compared with its precursor L-Kynurenine, which is frequently used in animal studies (KYNA cannot be metabolized to excitotoxic agents such as 3-hydroxy-L-kynurenine and quinolinic acid. We therefore investigated the possible effects of peripherally administered KYNA. Repetitive CSD waves were elicited by the application of 1 M KCl solution to the cortex. Direct current-electrocorticograms were measured for 1 hour. Four parameters of the waves were compared. Evans blue dye and fluorescent microscopy were used to study the possible changes in the permeability of the BBB. The results demonstrated that N-methyl-D-aspartate receptor antagonists can reduce the number of CSD waves and decrease

  12. Ursodeoxycholic acid, 7-ketolithocholic acid, and chenodeoxycholic acid are primary bile acids of the nutria (Myocastor coypus). (United States)

    Tint, G S; Bullock, J; Batta, A K; Shefer, S; Salen, G


    Because ursodeoxycholic and chenodeoxycholic acids are interconverted in humans via 7-ketolithocholic acid, bile acid metabolism was studied in the nutria (Myocastor coypus), the bile of which is known to contain these three bile acids. Relative concentrations of ursodeoxycholic (37% +/- 20%), 7-ketolithocholic (33% +/- 17%), and chenodeoxycholic (17% +/- 9%) acids in gallbladder bile were unchanged by 5-20 h of complete biliary diversion (n = 7). Injection of either [14C]cholesterol, [14C]ursodeoxycholic, [14C]7-ketolithocholic acid, or a mixture of [7 beta-3H]chenodeoxycholic acid and [14C]chenodeoxycholic acid into bile fistula nutria demonstrated that all three bile acids can be synthesized hepatically from cholesterol, that they are interconverted sparingly (2%-5%) by the liver, but that 7-ketolithocholic acid is an intermediate in the hepatic transformation of chenodeoxycholic acid to ursodeoxycholic acid. An animal that had been fed antibiotics showed an unusually elevated concentration of ursodeoxycholic acid in gallbladder and hepatic bile, suggesting that bacterial transformation of ursodeoxycholic acid in the intestine may be a source of some biliary chenodeoxycholic acid and 7-ketolithocholic acid.

  13. acetyl amino acids and dipeptides

    African Journals Online (AJOL)

    Chemistry. 2-(2'-Isopropyl-5'-methylphenoxy)acetic acid (1) was prepared by phenoxylation of thymol by using chloroacetic acid in alkaline conditions. Dipeptides Boc-Gly-Gly-OMe, Boc-Pro-Pro-. OMe and Boc-Ala-Leu-OMe were prepared from the corresponding amino acid methyl esters and Boc-amino acids using DCC ...

  14. ORF Alignment: NC_002945 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available osphoribosyltransferase (Qaprtase) From ... Mycobacterium Tuberculosis In Complex With Phthalate And ...b|1QPR|D Chain D, Quinolinate ... Phosphoribosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis...horibosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis In Com...e (Qaprtase) From Mycobacterium ... Tuberculosis In Complex With Phthalate And Prpcp ... pdb|1...cture Of Quinolinic Acid ... Phosphoribosyltransferase From Mycobacterium ... Tuberculosis: A

  15. ORF Alignment: NC_002755 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available osphoribosyltransferase (Qaprtase) From ... Mycobacterium Tuberculosis In Complex With Phthalate And ...b|1QPR|D Chain D, Quinolinate ... Phosphoribosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis...horibosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis In Com...e (Qaprtase) From Mycobacterium ... Tuberculosis In Complex With Phthalate And Prpcp ... pdb|1...cture Of Quinolinic Acid ... Phosphoribosyltransferase From Mycobacterium ... Tuberculosis: A

  16. ORF Alignment: NC_000962 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available osphoribosyltransferase (Qaprtase) From ... Mycobacterium Tuberculosis In Complex With Phthalate And ...b|1QPR|D Chain D, Quinolinate ... Phosphoribosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis...horibosyltransferase (Qaprtase) From Mycobacterium ... Tuberculosis In Com...e (Qaprtase) From Mycobacterium ... Tuberculosis In Complex With Phthalate And Prpcp ... pdb|1...cture Of Quinolinic Acid ... Phosphoribosyltransferase From Mycobacterium ... Tuberculosis: A

  17. Efficient example of cross-linked polymeric catalysed synthesis of ...

    Indian Academy of Sciences (India)

    ... sulphonic acid) (AMPS) was found to be an efficient heterogeneous catalyst for direct synthesis of 7-benzo[ℎ]indeno[1, 2-]quinolin-8-one and 8-naphtho[2, 3-ℎ]indeno[1, 2-]quinolin-9-one derivatives through one-pot condensation of aromatic aldehydes, 1, 3-indandione and 1-naphthylamine or 1-antharacylamine.

  18. Acid rain in Asia (United States)

    Bhatti, Neeloo; Streets, David G.; Foell, Wesley K.


    Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.

  19. Whither Acid Rain?

    Directory of Open Access Journals (Sweden)

    Peter Brimblecombe


    Full Text Available Acid rain, the environmental cause célèbre of the 1980s seems to have vanished from popular conscience. By contrast, scientific research, despite funding difficulties, has continued to produce hundreds of research papers each year. Studies of acid rain taught much about precipitation chemistry, the behaviour of snow packs, long-range transport of pollutants and new issues in the biology of fish and forested ecosystems. There is now evidence of a shift away from research in precipitation and sulfur chemistry, but an impressive theoretical base remains as a legacy.

  20. 2-arylureidobenzoic acids

    DEFF Research Database (Denmark)

    Valgeirsson, Jon; Nielsen, Elsebet Ø; Peters, Dan


    A series of 2-arylureidobenzoic acids (AUBAs) was prepared by a short and effective synthesis, and the pharmacological activity at glutamate receptors was evaluated in vitro and in vivo. The compounds showed noncompetitive antagonistic activity at the kainate receptor subtype GluR5. The most potent...... on the benzoic acid moiety (ring A), whereas ring B tolerated a variety of substituents, but with a preference for lipophilic substituents. The most potent compounds had a 4-chloro substituent on ring A and 3-chlorobenzene (6b), 2-naphthalene (8h), or 2-indole (8k) as ring B and had IC(50) values of 1.3, 1...

  1. The Acid-Base Titration of a Very Weak Acid: Boric Acid (United States)

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.


    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  2. Catalytic acetoxylation of lactic acid to 2-acetoxypropionic acid, en route to acrylic acid

    NARCIS (Netherlands)

    Beerthuis, R.; Granollers, M.; Brown, D.R.; Salavagione, H.J.; Rothenberg, G.; Shiju, N.R.


    We present an alternative synthetic route to acrylic acid, starting from the platform chemical lactic acid and using heterogeneous catalysis. To improve selectivity, we designed an indirect dehydration reaction that proceeds via acetoxylation of lactic acid to 2-acetoxypropionic acid. This

  3. Oxalic acid excretion after intravenous ascorbic acid administration (United States)

    Robitaille, Line; Mamer, Orval A.; Miller, Wilson H.; Levine, Mark; Assouline, Sarit; Melnychuk, David; Rousseau, Caroline; Hoffer, L. John


    Ascorbic acid is frequently administered intravenously by alternative health practitioners and, occasionally, by mainstream physicians. Intravenous administration can greatly increase the amount of ascorbic acid that reaches the circulation, potentially increasing the risk of oxalate crystallization in the urinary space. To investigate this possibility, we developed gas chromatography mass spectrometry methodology and sampling and storage procedures for oxalic acid analysis without interference from ascorbic acid and measured urinary oxalic acid excretion in people administered intravenous ascorbic acid in doses ranging from 0.2 to 1.5 g/kg body weight. In vitro oxidation of ascorbic acid to oxalic acid did not occur when urine samples were brought immediately to pH less than 2 and stored at –30°C within 6 hours. Even very high ascorbic acid concentrations did not interfere with the analysis when oxalic acid extraction was carried out at pH 1. As measured during and over the 6 hours after ascorbic acid infusions, urinary oxalic acid excretion increased with increasing doses, reaching approximately 80 mg at a dose of approximately 100 g. We conclude that, when studied using correct procedures for sample handling, storage, and analysis, less than 0.5% of a very large intravenous dose of ascorbic acid is recovered as urinary oxalic acid in people with normal renal function. PMID:19154961

  4. [Studies on interaction of acid-treated nanotube titanic acid and amino acids]. (United States)

    Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang


    Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

  5. Determination of Sialic Acids by Acidic Ninhydrin Reaction


    Yao,Kenzabroh; Ubuka,Toshihiko


    A new acidic ninhydrin method for determining free sialic acids is described. The method is based on the reaction of sialic acids with Gaitonde's acid ninhydrin reagent 2 which yields a stable color with an absorption maximum at 470 nm. The standard curve is linear in the range of 5 to 500 nmol of N-acetylneuraminic acid per 0.9 ml of reaction mixture. The reaction was specific only for sialic acids among the various sugars and sugar derivatives examined. Some interference of this method by c...

  6. octadecenoic acid in tomato

    African Journals Online (AJOL)


    ,12,13-. THODA. It has recently been shown that the enzyme peroxygenase is involved in the synthe- sis of 9,12,13-THODA in tomato fruits and that this trihydroxy fatty acid was probably further broken down or converted into other metabo-.

  7. Multifunctional Cinnamic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Aikaterini Peperidou


    Full Text Available Our research to discover potential new multitarget agents led to the synthesis of 10 novel derivatives of cinnamic acids and propranolol, atenolol, 1-adamantanol, naphth-1-ol, and (benzylamino ethan-1-ol. The synthesized molecules were evaluated as trypsin, lipoxygenase and lipid peroxidation inhibitors and for their cytotoxicity. Compound 2b derived from phenoxyphenyl cinnamic acid and propranolol showed the highest lipoxygenase (LOX inhibition (IC50 = 6 μΜ and antiproteolytic activity (IC50 = 0.425 μΜ. The conjugate 1a of simple cinnamic acid with propranolol showed the higher antiproteolytic activity (IC50 = 0.315 μΜ and good LOX inhibitory activity (IC50 = 66 μΜ. Compounds 3a and 3b, derived from methoxylated caffeic acid present a promising combination of in vitro inhibitory and antioxidative activities. The S isomer of 2b also presented an interesting multitarget biological profile in vitro. Molecular docking studies point to the fact that the theoretical results for LOX-inhibitor binding are identical to those from preliminary in vitro study.

  8. Fenofibric acid for hyperlipidemia. (United States)

    Saurav, Alok; Kaushik, Manu; Mohiuddin, Syed M


    3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (i.e., statins) are the mainstay of therapy for hyperlipidemia, as per the current National Cholesterol Education Program (NCEP) recommendation. However, the role of other agents, such as the fibrates, is continually being debated in the context of incremental risk reduction, especially in the setting of mixed dyslipidemia. Results from the ACCORD Trial have further added to the confusion. Fibrates also have a role to play in familial hyperlipidemias and in hypertriglyceridemia. Fenofibric acid is one of the newly approved forms of fenofibrate with enhanced bioavailability and was recently approved by the Food and Drug Administation (FDA) for the treatment of various types of hyperlipidemia, in conjunction with statins. This article reviews the role of fenofibric acid in the context of results from recent randomized trials on fenofibrate, including the ACCORD Trial. It discusses the current status of fenofibric acid in the management of dyslipidemia, especially in combination with statins, and also addresses the comparative efficacy and safety profile of this new molecule against other agents in its class. Fenofibric acid in combination with low- to moderate-dose statins is an effective and safe option in the treatment of mixed dyslipidemia, although the long-term effects on cardiovascular risk reduction need to be explored further.

  9. Hyaluronic Acid Assays

    DEFF Research Database (Denmark)

    Itenov, Theis S; Kirkby, Nikolai S; Bestle, Morten H


    BACKGROUD: Hyaluronic acid (HA) is proposed as a marker of functional liver capacity. The aim of the present study was to compare a new turbidimetric assay for measuring HA with the current standard method. METHODS: HA was measured by a particle-enhanced turbidimetric immunoassay (PETIA) and enzyme...

  10. Phenylpyruvic acid in urine

    NARCIS (Netherlands)

    Meulemans, O.; Vergeer, E.G.

    The method of The, Fleury And Vink for the determination of phenylpyruvic acid (PPA) in urine is modified by measuring the extinction after the green colour with ferric chloride has faded, and subtracting this extinction from that found initially. More accurate values are obtained and low PPA values

  11. Pantothenic acid and biotin (United States)

    ... Function Pantothenic acid and biotin are needed for growth. They help the body break down and use ... pregnancy Lactation: 7 mg/day *Adequate Intake (AI) Dietary Reference Intakes ... best way to get the daily requirement of essential vitamins is to eat a balanced ...

  12. furfural and acetic acid

    African Journals Online (AJOL)

    Investigating the effects of two lignocellulose degradation by-products (furfural and acetic acid) on ethanol fermentations by six ethanologenic yeast strains. ... Among the tested yeast strains, 1300 exhibited the highest growth rate, thus can be a promising candidate for mass production of bioethanol. Three important ...

  13. Nanoclusters of Cyanuric Acid

    Indian Academy of Sciences (India)

    Hydrogen bonding; molecular clusters; cyanuric acid; self-assembly; symmetry. ... Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai 600 020, India; Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA; Indian Institute of Science Education and ...

  14. Koetjapic acid chloroform hemisolvate

    Directory of Open Access Journals (Sweden)

    Z. D. Nassar


    Full Text Available The asymmetric unit of the title compound, C30H46O4·0.5CHCl3, consists of one koetjapic acid [systematic name: (3R,4aR,4bS,7S,8S,10bS,12aS-7-(2-carboxyethyl-3,4b,7,10b,12a-pentamethyl-8-(prop-1-en-2-yl-1,2,3,4,4a,4b,5,6,7,8,9,10,10b,11,12,12a-hexadecahydrochrysene-3-carboxylic acid] molecule and one half-molecule of chloroform solvent, which is disordered about a twofold rotation axis. The symmetry-independent component is further disordered over two sites, with occupancies of 0.30 and 0.20. The koetjapic acid contains a fused four-ring system, A/B/C/D. The A/B, B/C and C/D junctions adopt E/trans/cis configurations, respectively. The conformation of ring A is intermediate between envelope and half-chair and ring B adopts an envelope conformation whereas rings C and D adopt chair conformations. A weak intramolecular C—H...O hydrogen bond is observed. The koetjapic acid molecules are linked into dimers by two pairs of intermolecular O—H...O hydrogen bonds. The dimers are stacked along the c axis.

  15. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert


    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  16. Pharmacological properties of 3-amino-5,6,7,8-tetrahydro-2-[4-[4-(quinolin-2-yl)piperazin-1-yl]butyl]quinazolin-4(3H)-one (TZB-30878), a novel therapeutic agent for diarrhea-predominant irritable bowel syndrome (IBS) and its effects on an experimental IBS model. (United States)

    Tamaoki, Satoru; Yamauchi, Yukinao; Nakano, Youichi; Sakano, Sayuri; Asagarasu, Akira; Sato, Michitaka


    3-Amino-5,6,7,8-tetrahydro-2-[4-[4-(quinolin-2-yl)piperazin-1-yl]butyl]quinazolin-4(3H)-one (TZB-30878) is a novel compound with both 5-hydroxytryptamine (5-HT)(1A) agonism and 5-HT(3) antagonism effects. We hypothesized that TZB-30878 might have benefits from these dual effects as a medication for diarrhea-predominant irritable bowel syndrome (d-IBS), and these studies were designed to confirm the pharmacological properties of TZB-30878 and its efficacy in an IBS-like animal model. The binding assays demonstrated that [(3)H]TZB-30878 selectively binds to human 5-HT(1A) and 5-HT(3) receptors, with K(d) values of 0.68 +/- 0.03 and 8.90 +/- 1.73 nM, respectively. Systemic administration of TZB-30878 inhibited 5-HT-induced bradycardia in a dose-dependent manner in rats. In behavioral assays TZB-30878 produced signs of 5-HT syndrome in rats. These results suggest that TZB-30878 has dual effects as a 5-HT(1A) receptor agonist and a 5-HT(3) receptor antagonist. Finally, we evaluated the effects of TZB-30878 on wrap restraint stress-induced defecation in an IBS-like model in rats. TZB-30878 (1-10 mg/kg p.o.) normalized stress-induced defecation in a dose-dependent manner, whereas the 5-HT(1A) agonist tandospirone (30 and 100 mg/kg p.o.) and the 5-HT(3) antagonist alosetron (1-10 mg/kg p.o.) did not show such effects. Furthermore, this efficacy of TZB-30878 was partly antagonized by a 5-HT(1A) antagonist, [O-methyl-3H]-N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide trihydrochloride (WAY-100635). These results suggest that 5-HT(1A) receptor agonism and 5-HT(3) receptor antagonism contribute to the efficacy of TZB-30878 in the IBS-like model. The efficacy of TZB-30878 supports the concept that the presence of both actions, namely 5-HT(1A) receptor agonism and 5-HT(3) receptor antagonism, could be an important mechanism in the treatment of d-IBS.

  17. Fatty acid-producing hosts (United States)

    Pfleger, Brian F; Lennen, Rebecca M


    Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at C. Methods of producing a fatty acid product comprising culturing such hosts at C. are also described.

  18. How salicylic acid takes transcriptional control over jasmonic acid signaling

    National Research Council Canada - National Science Library

    Caarls, Lotte|info:eu-repo/dai/nl/371746213; Pieterse, Corné M J|info:eu-repo/dai/nl/113115113; van Wees, Saskia C M|info:eu-repo/dai/nl/185445373


    Transcriptional regulation is a central process in plant immunity. The induction or repression of defense genes is orchestrated by signaling networks that are directed by plant hormones of which salicylic acid (SA) and jasmonic acid (JA...

  19. Progress in engineering acid stress resistance of lactic acid bacteria. (United States)

    Wu, Chongde; Huang, Jun; Zhou, Rongqing


    Lactic acid bacteria (LAB) are widely used for the production of a variety of fermented foods, and are considered as probiotic due to their health-promoting effect. However, LAB encounter various environmental stresses both in industrial fermentation and application, among which acid stress is one of the most important survival challenges. Improving the acid stress resistance may contribute to the application and function of probiotic action to the host. Recently, the advent of genomics, functional genomics and high-throughput technologies have allowed for the understanding of acid tolerance mechanisms at a systems level, and many method to improve acid tolerance have been developed. This review describes the current progress in engineering acid stress resistance of LAB. Special emphasis is placed on engineering cellular microenvironment (engineering amino acid metabolism, introduction of exogenous biosynthetic capacity, and overproduction of stress response proteins) and maintaining cell membrane functionality. Moreover, strategies to improve acid tolerance and the related physiological mechanisms are also discussed.

  20. Animosity towards Acid Attacks - Critical Study on Acid Victimization


    Chandrashekar, S.V; Eldo Johny


    Animosity to acid attacks is deliberated as foulest acts, a form of gender terrorism within the feminist read. It’s a form of vicious violence outlined as acid throwing or Vitriolage. In India, there are component varied incident were reported, as most precarious victimization of individuals by deforming their body. The condition of victims of acid attacks is unit in serious frustrating their entire life. Acid victimization has deliberated globally and even several countries area unit sensiti...

  1. Effect of phenolic acids on glucose and organic acid metabolism by lactic acid bacteria from wine. (United States)

    Campos, Francisco M; Figueiredo, Ana R; Hogg, Tim A; Couto, José A


    The influence of phenolic (p-coumaric, caffeic, ferulic, gallic and protocatechuic) acids on glucose and organic acid metabolism by two strains of wine lactic acid bacteria (Oenococcus oeni VF and Lactobacillus hilgardii 5) was investigated. Cultures were grown in modified MRS medium supplemented with different phenolic acids. Cellular growth was monitored and metabolite concentrations were determined by HPLC-RI. Despite the strong inhibitory effect of most tested phenolic acids on the growth of O. oeni VF, the malolactic activity of this strain was not considerably affected by these compounds. While less affected in its growth, the capacity of L. hilgardii 5 to degrade malic acid was clearly diminished. Except for gallic acid, the addition of phenolic acids delayed the metabolism of glucose and citric acid in both strains tested. It was also found that the presence of hydroxycinnamic acids (p-coumaric, caffeic and ferulic) increased the yield of lactic and acetic acid production from glucose by O. oeni VF and not by L. hilgardii 5. The results show that important oenological characteristics of wine lactic acid bacteria, such as the malolactic activity and the production of volatile organic acids, may be differently affected by the presence of phenolic acids, depending on the bacterial species or strain.

  2. Kinetics of oxidation of acidic amino acids by sodium N ...

    Indian Academy of Sciences (India)


    Keywords. Acidic amino acids; bromamine-B; oxidation kinetics, acid medium. 1. Introduction. The chemistry of aromatic sulphonyl haloamines has evoked considerable interest, as they are sources of halonium cations, hypohalite species, and N-anions which act both as bases and nucleophiles. The prominent members of ...

  3. Acetic acid extraction from aqueous solutions using fatty acids

    NARCIS (Netherlands)

    IJmker, H.M.; Gramblicka, M.; Kersten, Sascha R.A.; van der Ham, Aloysius G.J.; Schuur, Boelo


    A major challenge for production of acetic acid via bio-based routes is cost-effective concentration and purification of the acetic acid from the aqueous solutions, for which liquid–liquid extraction is a possible method. A main challenge in extraction of acetic acid from dilute aqueous solutions is

  4. Effect of hydrofluoric acid on acid decomposition mixtures for ...

    African Journals Online (AJOL)

    Effect of hydrofluoric acid on acid decomposition mixtures for determining iron and other metallic elements in green vegetables. ... Therefore, the inclusion of HF in the acid decomposition mixtures would ensure total and precise estimation of Fe in plant materials, but not critical for analysis of Mn, Mg, Cu, Zn and Ca.

  5. Selective hydrodeoxygenation of tartaric acid to succinic acid

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Jiayi [Department of Chemical and Biomolecular Engineering; University of Delaware; Newark; USA; Catalysis Center for Energy Innovation; Vasiliadou, Efterpi S. [Catalysis Center for Energy Innovation; University of Delaware; Newark; USA; Goulas, Konstantinos A. [Catalysis Center for Energy Innovation; University of Delaware; Newark; USA; Saha, Basudeb [Catalysis Center for Energy Innovation; University of Delaware; Newark; USA; Vlachos, Dionisios G. [Department of Chemical and Biomolecular Engineering; University of Delaware; Newark; USA; Catalysis Center for Energy Innovation


    A novel one-step process for the selective production of succinic acid from tartaric acid is developed. High succinic yield is achieved in an efficient catalytic system comprised of MoOx/BC, HBr and acetic acid under hydrogen atmosphere.

  6. Amino acids analysis during lactic acid fermentation by single strain ...

    African Journals Online (AJOL)



    Jul 9, 2014 ... of the three LAB strains to utilize amino acids for growth and lactic acid production were employed to ... Lactic acid bacteria (LAB), which are used for the .... broth. These findings confirm that L. salivarius released alanine and glycine, which are non-essential for the growth of this bacterium. P. acidilactici ...

  7. Kinetics of oxidation of acidic amino acids by sodium N ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 113; Issue 4. Kinetics of oxidation of acidic amino acids by sodium N-bromobenzenesulphonamide in acid medium: A mechanistic approach ... Department of Post-Graduate Studies in Chemistry, Central College, Bangalore University, Bangalore 560 001, India ...

  8. Effects of TAK-480, a novel tachykinin NK(2)-receptor antagonist, on visceral hypersensitivity in rabbits and ricinoleic acid-induced defecation in guinea pigs. (United States)

    Tanaka, Takahiro; Tanaka, Akiko; Nakamura, Akihiro; Matsushita, Kozo; Imanishi, Akio; Matsumoto-Okano, Shiho; Inatomi, Nobuhiro; Miura, Kasei; Toyoda, Masao; Mizojiri, Gaku; Tsukimi, Yasuhiro


    TAK-480, 4-(difluoromethoxy)-N-((1R,2S)-2-(((3aR,4R,9bR)-4-(methoxymethyl)-2, 3,3a,4,5,9b-hexahydro-1H-pyrrolo[3,2-c]quinolin-1-yl)carbonyl)cyclohexyl)benzamide, is a novel tachykinin NK(2)-receptor antagonist. In this study, we investigated its antagonistic activity and efficacy in animal models of visceral hypersensitivity and stimulated bowel function which have been implicated to underlie the symptoms in irritable bowel syndrome (IBS). TAK-480 showed potent binding affinity for human NK(2) receptors with a marked species difference and a 10,000-fold selectivity versus NK(1) and NK(3) receptors. TAK-480 dose-dependently antagonized colonic contractions induced by administration of the NK(2) receptor-selective agonist beta-Ala(8)-NKA(4-10) (βA-NKA) in anesthetized rabbits. In a rabbit model of intracolonic zymosan-induced visceral hypersensitivity, TAK-480 markedly inhibited the visceromotor response to colorectal distension, in contrast to the moderate inhibition by the serotonin 5-HT(3)-receptor antagonist alosetron. In addition, TAK-480 suppressed ricinoleic acid-induced defecation without affecting spontaneous defecation in guinea pigs, whereas alosetron suppressed both. Furthermore, TAK-480 inhibited smooth muscle contractions produced by natural tachykinins (substance P, neurokinin A, and neurokinin B) as well as βA-NKA in an isolated human colon. In conclusion, the novel NK(2)-receptor antagonist TAK-480 improved visceral hypersensitivity and accelerated defecation without causing constipation in experimental animals. Furthermore, the potent functional blockade of NK(2) receptors in human colon might suggest the potential effectiveness of TAK-480 in IBS patients.

  9. l-kynurenine combined with probenecid and the novel synthetic kynurenic acid derivative attenuate nitroglycerin-induced nNOS in the rat caudal trigeminal nucleus. (United States)

    Vámos, Eniko; Párdutz, Arpád; Varga, Hedvig; Bohár, Zsuzsanna; Tajti, János; Fülöp, Ferenc; Toldi, József; Vécsei, László


    Systemic administration of the nitric oxide (NO) donor nitroglycerin (NTG) triggers a delayed attack without aura in many migraineurs, but not in healthy volunteers. In rats, 4 h after the systemic administration of NTG (10 mg/kg bw, s.c.), the neurons of the caudal trigeminal nucleus (TNC) are activated and the expression of neuronal NO synthase (nNOS) in the same area is increased suggesting a self-amplifying process in the trigeminal system, which seems to be crucial in migraine pathogenesis. Kynurenic acid (KYNA) and its analogues may exert modulatory effects in many neuropathological conditions, probably via N-methyl-D-aspartate (NMDA) antagonism. Since NMDA receptors play a crucial role in trigeminal pain processing, the aim of our experiments was to compare the effects of L-kynurenine (L-KYN) combined with probenecid (PROB) or with 2-(2-N,N-dimethylaminoethylamine-1-carbonyl)-1H-quinolin-4-one hydrochloride alone, a newly synthetized KYNA derivative, on the NTG-induced nNOS expression in the rat TNC. Pretreatment with L-KYN (300 mg/kg bw, i.p.) together with PROB (200 mg/kg bw, i.p.) and KYNA derivative (300 mg/kg bw, i.p.) attenuated the NTG-induced nNOS expression in the rat TNC. Our data suggest that the stimulating effect of NTG, and thus of NO, on the expression of nNOS might be modulated by increasing the KYNA level in the brain, probably through the NMDA receptors. These data could help promote a better understanding of the pathogenesis of headaches and the action of antimigraine drugs.

  10. Industrial ecotoxicology "acid rain". (United States)

    Astolfi, E; Gotelli, C; Higa, J


    The acid rain phenomenon was studied in the province of Cordoba, Argentina. This study, based on a previously outlined framework, determined the anthropogenic origin of the low pH due to the presence of industrial hydrochloric acid wastage. This industrial ecotoxicological phenomenon seriously affected the forest wealth, causing a great defoliation of trees and shrubs, with a lower effect on crops. A survey on its effects on human beings has not been carried out, but considering the corrosion caused to different metals and its denouncing biocide effect on plants and animals, we should expect to find some kind of harm to the health of the workers involved or others engaged in farming, and even to those who are far away from the polluting agent.

  11. Halogenated fatty acids

    DEFF Research Database (Denmark)

    Mu, Huiling; Sundin, Peter; Wesén, Clas


    and separation method. This review covers separation by solid phase chromatography, gel permeation chromatography, and liquid-liquid extraction, followed by halogen determination. All studies performed according to this outline have indicated that the major organohalogen compounds are chlorinated fatty acids...... bound in different lipids. For the detection and identification of individual, halogenated fatty acid methyl esters (FAMEs) liberated from the lipids, gas chromatography (GC) has been employed together with detection methods such as electron capture detection, electrolytic conductivity detection (ELCD......), atomic emission spectrometry, and mass spectrometry. For most environmental samples, chlorinated FAMEs must be enriched prior to GC. ELCD is a useful detection method for indicating halogenated FAMEs in the chromatograms, and tentative identification of the halogenated species can be obtained...

  12. N-(3-Chlorophenylmaleamic acid

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda


    Full Text Available In the title compound, C10H8ClNO3, the molecular conformation is stabilized by two intramolecular hydrogen bonds. The first is a short O—H...O hydrogen bond within the maleamic acid unit and the second is a C—H...O hydrogen bond which connects the amide group with the phenyl ring. The maleamic acid unit is essentially planar, with an r.m.s. deviation of 0.044 Å, and makes a dihedral angle of 15.2 (1° with the phenyl ring. In the crystal, intermolecular N—H...O hydrogen bonds link the molecules into C(7 chains running [010].

  13. N-(3-Methylphenylsuccinamic acid

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda


    Full Text Available In the crystal structure of the title compound, C11H13NO3, the conformations of the N—H and C=O bonds in the amide segment are anti to each other, and that of the amide H atom is anti to the meta-methyl group in the benzene ring. Furthermore, the conformations of the amide oxygen and the carbonyl O atom of the acid segment are also anti to the adjacent –CH2 groups. The C=O and O—H bonds of the acid group are syn to each other. In the crystal, the molecules are packed into infinite chains through intermolecular N—H...O and O—H...O hydrogen bonds.

  14. Radioimmunoassay for jasmonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Knoefel, H.D.; Brueckner, C.; Kramell, R.; Sembdner, G.; Schreiber, K. (Akademie der Wissenschaften der DDR, Halle/Saale. Inst. fuer Biochemie der Pflanzen)


    A radioimmunoassay (RIA) for the natural plant growth regulator jasmonic acid (JA) was developed. The antiserum was raised in rabbits against (+-)-JA linked to bovine serum albumin. As tracer tritium labelled (+-)-JA (spec. act. 7.4 x 10/sup 9/ Bq x mmol/sup -1/) was used. Cross-reactivity studies with compounds structurally related to JA demonstrated the antiserum to be specific for JA, abscisic acid normally present in the same extract does not interfer. The RIA has a detection limit of 2 ng (-)-JA methylester, a measuring range 2-200 ng, and no extensive purification is required prior to estimation. Therefore, in JA analysis the RIA described is superior to GC, HPLC, and bioassay. This new method has been employed for studies on the distribution of JA in different plant organs of the broad bean, Vicia faba L.

  15. (Radioiodinated free fatty acids)

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, Jr., F. F.


    The traveler participated in the Second International Workshop on Radioiodinated Free Fatty Acids in Amsterdam, The Netherlands where he presented an invited paper describing the pioneering work at the Oak Ridge National Laboratory (ORNL) involving the design, development and testing of new radioiodinated methyl-branched fatty acids for evaluation of heart disease. He also chaired a technical session on the testing of new agents in various in vitro and in vivo systems. He also visited the Institute for Clinical and Experimental Nuclear Medicine in Bonn, West Germany, to review, discuss, plan and coordinate collaborative investigations with that institution. In addition, he visited the Cyclotron Research Center in Liege, Belgium, to discuss continuing collaborative studies with the Osmium-191/Iridium-191m radionuclide generator system, and to complete manuscripts and plan future studies.

  16. Humic acid protein complexation


    Tan, W.F.; Koopal, L.K.; Weng, L.P.; Riemsdijk, van, J.F.; Norde, W.


    Interactions of purified Aldrich humic acid (PAHA) with lysozyme (LSZ) are investigated. In solution LSZ is moderately positively and PAHA negatively charged at the investigated pH values. The proton binding of PAHA and of LSZ is determined by potentiometric proton titrations at various KCl concentrations. It is also measured for two mixtures of PAHA¿LSZ and compared with theoretically calculated proton binding assuming no mutual interaction. The charge adaptation due to PAHA¿LSZ interaction ...

  17. octadecenoic acid in tomato

    African Journals Online (AJOL)


    The MMS medium was a mixture of 2.15 g of Murashige and Skoog me- dium, 0.97g of 2-(N-morpholino) ethanesulphonic acid and 10 g of saccharose in. 500 ml of distilled water. The pH of the MMS medium was adjusted to 5.6 with 1 M KOH solution. Plant material and treatments. Tomato (Solanum lycopersicum L. cv ...



    Buriticá, Jorge Eduardo; Jorge Eduardo Buriticá: Cirujano General U. de Caldas, Profesor de Cirugía U. de Manizales. Profesor pregrado y postgrado U. de Caldas.; Becerra, Luis Fernando; Luis Fernando Becerra : Cirujano general CES Medellín, Docente U de Manizales, U de Caldas.; Salazar Osorio, Alejandro; Alejandro Salazar Osorio: Médico General U. de Manizales.


      Acid peptic disease (PAD) constitutes one of the most frequent queries in general medical practice, both in the emergency department and outpatient external; for this reason it is essential for good general practitioner, snagging a concrete and firm knowledge about this subject. Moreover, not only about this specific pathology but from its complications such as the digestive bleeding, although this would be a different item for which we are concerned in this review. There are areas of predo...

  19. Bile acids for viral hepatitis

    DEFF Research Database (Denmark)

    Chen, Weikeng; Liu, J; Gluud, C


    Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness.......Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness....

  20. Biological properties of lipoic acid

    Directory of Open Access Journals (Sweden)

    Anna Bilska


    Full Text Available Lipoic acid is a prostetic group of H-protein of the glycine cleavage system and the dihydrolipoamide acyltransferases (E2 of the pyruvate, alpha-ketoglutarate and branched-chain alpha-keto acid dehydrogenase complexes. Lipoic acid and its reduced form, dihydrolipoic acid, reacts with oxygen reactive species. This paper reviews the beneficial effects in oxidative stress models or clinical conditions.

  1. Comparison of in vivo binding properties of the 18-kDa translocator protein (TSPO) ligands [{sup 18}F]PBR102 and [{sup 18}F]PBR111 in a model of excitotoxin-induced neuroinflammation

    Energy Technology Data Exchange (ETDEWEB)

    Callaghan, P.D.; Gregoire, M.C. [Australian Nuclear Science and Technology Organisation, ANSTO LifeSciences, Kirrawee DC, NSW (Australia); University of Sydney, Brain and Mind Research Institute, Sydney (Australia); University of Sydney, Discipline of Medical Radiation Sciences, Sydney (Australia); Wimberley, C.A.; Rahardjo, G.L.; Berghofer, P.J.; Zahra, D. [Australian Nuclear Science and Technology Organisation, ANSTO LifeSciences, Kirrawee DC, NSW (Australia); University of Sydney, Brain and Mind Research Institute, Sydney (Australia); Pham, T.Q.; Jackson, T.; Wyatt, N.; Greguric, I.; Howell, N.R.; Loc' h, C. [Australian Nuclear Science and Technology Organisation, ANSTO LifeSciences, Kirrawee DC, NSW (Australia); Bourdier, T.; Mattner, F.; Katsifis, A. [Australian Nuclear Science and Technology Organisation, ANSTO LifeSciences, Kirrawee DC, NSW (Australia); Royal Prince Alfred Hospital, Department of Molecular Imaging, Sydney (Australia); Siegele, R.; Pastuovic, Z. [Institute for Environmental Research, Centre for Accelerator Science, ANSTO, Sydney (Australia)


    The in vivo binding parameters of the novel imidazopyridine TSPO ligand [{sup 18}F]PBR102 were assessed and compared with those of [{sup 18}F]PBR111 in a rodent model of neuroinflammation. The validity of the key assumptions of the simplified reference tissue model (SRTM) for estimation of binding potential (BP) was determined, with validation against a two-tissue compartment model (2TC). Acute neuroinflammation was assessed 7 days after unilateral stereotaxic administration of (R,S)-α-amino-3-hydroxy-5-methyl-4-isoxazolopropionique (AMPA) in anaesthetized adult Wistar rats. Anaesthetized rats were implanted with a femoral arterial cannula then injected with a low mass of [{sup 18}F]PBR102 or [{sup 18}F]PBR111 and dynamic images were acquired over 60 min using an INVEON PET/CT camera. Another population of rats underwent the same PET protocol after pretreatment with a presaturating mass of the same unlabelled tracer (1 mg/kg) to assess the validity of the reference region for SRTM analysis. Arterial blood was sampled during imaging, allowing pharmacokinetic determination of radiotracer concentrations. Plasma activity concentration-time curves were corrected for unchanged tracer based on metabolic characterization experiments in a separate cohort of Wistar rats. The stability of neuroinflammation in both imaging cohorts was assessed by [{sup 125}I] CLINDE TSPO quantitative autoradiography, OX42/GFAP immunohistochemistry, Fluoro-Jade C histology, and elemental mapping using microparticle-induced x-ray emission spectroscopy. The BP of each ligand were assessed in the two cohorts of lesioned animals using both SRTM and a 2TC with arterial parent compound concentration, coupled with the results from the presaturation cohort for comparison and validation of the SRTM. The BPs of [{sup 18}F]PBR102 [{sup 18}F]PBR111 were equivalent, with improved signal-to-noise ratio and sensitivity compared with [{sup 11}C]PK11195. The presaturation study showed differences in the volume of distribution between the ipsilateral striatum and the striatum contralateral to the injury (0.7) indicating that an assumption of the SRTM was not met. The modelling indicated that the BPs were consistent for both ligands. Between the SRTM and 2TC model, the BPs were highly correlated, but there was a bias in BP. [{sup 18}F]PBR102 and [{sup 18}F]PBR111 have equivalent binding properties in vivo, displaying significantly greater BPs with lower signal-to-noise ratio than [{sup 11}C]PK11195. While an assumption of the SRTM was not met, this modelling approach was validated against 2TC modelling for both ligands, facilitating future use in longitudinal PET imaging of neuroinflammation. (orig.)

  2. Acids and bases solvent effects on acid-base strenght

    CERN Document Server

    Cox, Brian G


    Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

  3. Fumaric acid production by fermentation

    NARCIS (Netherlands)

    Roa Engel, C.A.; Straathof, A.J.J.; Zijlmans, T.W.; Van Gulik, W.M.; Van der Wielen, L.A.M.


    Abstract The potential of fumaric acid as a raw material in the polymer industry and the increment of cost of petroleum-based fumaric acid raises interest in fermentation processes for production of this compound from renewable resources. Although the chemical process yields 112% w/w fumaric acid

  4. [Total synthesis of nordihydroguaiaretic acid]. (United States)

    Wu, A X; Zhao, Y R; Chen, N; Pan, X F


    beta-Keto ester(5) was obtained from vanilin through etherification, oxidation and condensation with acetoacetic ester, (5) on oxidative coupling reaction by NaOEt/I2 produced dimer (6) in high yield. Acid catalyzed cyclodehydration of (6) gave the furan derivative(7), and by a series of selective hydrogenation nordihydroguaiaretic acid, furoguaiacin dimethyl ether and dihydroguaiaretic acid dimethyl ether were synthesized.

  5. Excitatory amino acid receptor antagonists

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B


    We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation...

  6. Acid precipitation and forest soils (United States)

    C. O. Tamm


    Many soil processes and properties may be affected by a change in chemical climate such as that caused by acidification of precipitation. The effect of additions of acid precipitation depends at first on the extent to which this acid is really absorbed by the soil and on the changes in substances with actual or potential acidity leaving the soil. There is for instance...

  7. Hyaluronic Acid in Dermatology. (United States)

    Keen, Mohammad Abid


    Hyaluronic acid (HA) is a major component of the extracellular matrix of the skin and plays an important role in the metabolism of the dermis. It has a key position in wound healing and tissue repair processes owing to its ability to maintain a humid environment favorable to healing and the stimulation of growth factors, cellular constituents, and the migration of various cells essential for healing. This review aims to describe briefly the physical, chemical, and biologic properties of HA, together with some details of the dermatologic indications of this unique molecule.

  8. Crassulacean acid metabolism

    Directory of Open Access Journals (Sweden)

    Thomas David Geydan


    Full Text Available A review of Crassulacean acid metabolism is presented, characterized by showing the occurrence, activity and plasticity of these complex mechanism at the physiological, biochemical and molecular level, framed by the presence of the denominated four phases in CAM and its repercussion and expression due to different stresses in an ecological context. The basic enzymes, and metabolites necessary for the optional functioning of CAM are presented as well as their mode of action and cellular control. Finally, it is shown how environmental conditions and molecular signalling mediate the phenotypic plasticity.

  9. Protonation study of peroxynitric acid and peroxynitrous acid (United States)

    Santiano, Randy L.; Francisco, Joseph S.


    The equilibrium structures and harmonic vibrational frequencies of peroxynitric acid (HOONO2) and seven structures of protonated peroxynitric acid, along with peroxynitrous acid (HOONO) and its 12 protonated peroxynitrous acid structures, have been investigated using several ab initio and density functional methods. The ab initio methods include second-order Møller-Plesset perturbation theory, quadratic configuration interaction, including single and double excitations theory (QCISD), and the QCISD(T) methods, which incorporate a perturbational estimate of the effects of connected triple excitation. The Becke three-parameter hybrid functional combined with Lee, Yang, and Parr correlation function is the density functional method used. The lowest energy form of protonated peroxynitric acid is a complex between H2O2 and NO+ rather than between H2O and NO2+. For peroxynitrous acid, a complex between H2O2 and NO2+ is found to be the lowest energy structure. The ab initio proton affinity (PA) of HOONO and HOONO2 is predicted to be 182.1 and 175.1 kcal mol-1, respectively, at the QCISD(T)/6-311++G(3df,3pd) level of theory. The results are contrasted with an earlier study on nitrous acid, and is shown that peroxynitric acid and peroxynitrous acid have a smaller PA than nitrous acid.

  10. Adsorption of humic acid on acid-activated Greek bentonite. (United States)

    Doulia, Danae; Leodopoulos, Ch; Gimouhopoulos, K; Rigas, F


    The adsorption of humic acid on bentonite from Milos Island (Greece) acid-treated with dilute H(2)SO(4) solutions over a concentration range between 0.25 and 13M has been studied. Bentonite activated with 3M sulfuric acid (AAS) showed a higher efficiency in removing humic acid from aqueous solutions and was selected for further investigation. The specific surface area of acid-activated bentonite was estimated using the methylene blue adsorption method. The morphology of untreated, activated, and HA-sorbed bentonite was studied under scanning electron microscope (SEM). The effects of contact time, adsorbate concentration, adsorbent dose, and temperature on the adsorption of humic acid onto bentonite activated with 3M H(2)SO(4) were studied using a batch adsorption technique. Acidic pH and high ionic strength proved to be favorable for the adsorption efficiency. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were used to describe the kinetic data and the rate constants were evaluated. The experimental isotherm data were analyzed using Langmuir, Freundlich, and Temkin equations and the isotherm constants were determined. Thermodynamic parameters (DeltaH(o), DeltaS(o), and DeltaG(o)) of adsorption of humic acid onto acid-activated bentonite with 3M sulfuric acid were also evaluated.

  11. New Acid Combination for a Successful Sandstone Acidizing (United States)

    Shafiq, M. U.; Mahmud, H. K. B.; Rezaee, R.


    With the development of new enhanced oil recovery techniques, sandstone acidizing has been introduced and played a pivotal role in the petroleum industry. Different acid combinations have been applied, which react with the formation, dissolve the soluble particles; thus increase the production of hydrocarbons. To solve the problems which occurred using current preflush sandstone acidizing technology (hydrochloric acid); a new acid combination has been developed. Core flooding experiments on sandstone core samples with dimensions 1.5 in. × 3 in. were conducted at a flow rate of 2 cm3/min. A series of hydrochloric-acetic acid mixtures with different ratios were tested under 150°F temperature. The core flooding experiments performed are aimed to dissolve carbonate, sodium, potassium and calcium particles from the core samples. These experiments are followed by few important tests which include, porosity-permeability, pH value, Inductively Coupled Plasma (ICP) analysis and Nuclear Magnetic Resonance (NMR measurements). All the results are compared with the results of conventional hydrochloric acid technology. NMR and porosity analysis concluded that the new acid combination is more effective in creating fresh pore spaces and thus increasing the reservoir permeability. It can be seen from the pore distribution before and after the acidizing. Prior applying acid; the large size of pores appears most frequently in the pore distribution while with the applied acid, it was found that the small pore size is most the predominant of the pore distribution. These results are validated using ICP analysis which shows the effective removal of calcium and other positive ions from the core sample. This study concludes that the combination of acetic-hydrochloric acid can be a potential candidate for the preflush stage of sandstone acidizing at high temperature reservoirs.

  12. Simultaneous liquid-chromatographic quantitation of salicylic acid, salicyluric acid, and gentisic acid in urine. (United States)

    Cham, B E; Bochner, F; Imhoff, D M; Johns, D; Rowland, M


    We have developed a specific and sensitive method for the determination of salicylic acid, salicyluric acid, and gentisic acid in urine. Any proteins present are precipitated with methyl cyanide. After centrifugation, an aliquot of the supernate is directly injected into an octadecyl silane reversed-phase chromatographic column, then eluted with a mixture of water, butanol, acetic acid, and sodium sulfate, and quantitated at 313 nm by ultraviolet detection according to peak-height ratios (with internal standard, o-methoxybenzoic acid) or peak heights (no internal standard). The method allows estimates within 25 min. Sensitivity was 0.2 mg/L for gentisic acid, and 0.5 mg/L for both salicyluric and salicylic acid (20-micro L injection volume); response was linear with concentration to at least 2.000 g/L for salicylic acid and metabolites. Analytical recovery of salicylic acid and metabolites from urine is complete. Intra-assay precision (coefficient of variation) is 5.52% at 7.5 mg/L for salicylic acid, 5.01% at 9.33 mg/L for salicyluric acid, and 3.07% at 7.96 mg/L for gentisic acid. Interassay precision is 7.32% at 7.51 mg/L for salicylic acid, 5.52% at 8.58 mg/L for salicyluric acid, and 3.97% at 8.32 mg/L for gentisic acid. We saw no significant interference in urine from patients being treated with various drugs other than aspirin.

  13. Cryoprotection from lipoteichoic acid (United States)

    Rice, Charles V.; Middaugh, Amy; Wickham, Jason R.; Friedline, Anthony; Thomas, Kieth J.; Johnson, Karen; Zachariah, Malcolm; Garimella, Ravindranth


    Numerous chemical additives lower the freezing point of water, but life at sub-zero temperatures is sustained by a limited number of biological cryoprotectants. Antifreeze proteins in fish, plants, and insects provide protection to a few degrees below freezing. Microbes have been found to survive at even lower temperatures, and with a few exceptions, antifreeze proteins are missing. Survival has been attributed to external factors, such as the high salt concentration of brine veins and adhesion to particulates or ice crystal defects. We have discovered an endogenous cryoprotectant in the cell wall of bacteria, lipoteichoic acid biopolymers. Adding 1% LTA to bacteria cultures immediately prior to freezing provides 50% survival rate, similar to the results obtained with 1% glycerol. In the absence of an additive, bacterial survival is negligible as measured with the resazurin cell viability assay. The mode of action for LTA cryoprotection is unknown. With a molecular weight of 3-5 kDa, it is unlikely to enter the cell cytoplasm. Our observations suggest that teichoic acids could provide a shell of liquid water around biofilms and planktonic bacteria, removing the need for brine veins to prevent bacterial freezing.

  14. Bile Acid Physiology. (United States)

    Di Ciaula, Agostino; Garruti, Gabriella; Baccetto, Raquel Lunardi; Molina-Molina, Emilio; Bonfrate, Leonilde; Wang, David Q-H; Portincasa, Piero


    The primary bile acids (BAs) are synthetized from colesterol in the liver, conjugated to glycine or taurine to increase their solubility, secreted into bile, concentrated in the gallbladder during fasting, and expelled in the intestine in response to dietary fat, as well as bio-transformed in the colon to the secondary BAs by the gut microbiota, reabsorbed in the ileum and colon back to the liver, and minimally lost in the feces. BAs in the intestine not only regulate the digestion and absorption of cholesterol, triglycerides, and fat-soluble vitamins, but also play a key role as signaling molecules in modulating epithelial cell proliferation, gene expression, and lipid and glucose metabolism by activating farnesoid X receptor (FXR) and G-protein-coupled bile acid receptor-1 (GPBAR-1, also known as TGR5) in the liver, intestine, muscle and brown adipose tissue. Recent studies have revealed the metabolic pathways of FXR and GPBAR-1 involved in the biosynthesis and enterohepatic circulation of BAs and their functions as signaling molecules on lipid and glucose metabolism.


    Crozier, W J


    Measurements of the penetration of tissue from Chromodoris zebra are believed to show that a determining factor in penetration involves the establishment of a critical pH (near 3.5) in relation to superficial cell proteins. The rapidity with which this state is produced depends upon acid strength, and upon some property of the acid influencing the speed of absorption; hence it is necessary to compare acids within groups of chemical relationship. The actual speed of penetration observed with any acid is dependent upon two influences: preliminary chemical combination with the outer protoplasm, followed by diffusion. The variation of the temperature coefficient of penetration velocity with the concentration of acid, and the effect of size (age) of individual providing the tissue sample agree in demonstrating the significant part played by diffusion. In comparing different acids, however, their mode of chemical union with the protoplasm determines the general order of penetrating ability.

  16. Solid acid catalysis from fundamentals to applications

    CERN Document Server

    Hattori, Hideshi


    IntroductionTypes of solid acid catalystsAdvantages of solid acid catalysts Historical overviews of solid acid catalystsFuture outlookSolid Acids CatalysisDefinition of acid and base -Brnsted acid and Lewis acid-Acid sites on surfacesAcid strengthRole of acid sites in catalysisBifunctional catalysisPore size effect on catalysis -shape selectivity-Characterization of Solid Acid Catalysts Indicator methodTemperature programmed desorption (TPD) of ammoniaCalorimetry of adsorption of basic moleculesInfrare

  17. Citric acid production patent review. (United States)

    Anastassiadis, Savas; Morgunov, Igor G; Kamzolova, Svetlana V; Finogenova, Tatiana V


    Current Review article summarizes the developments in citric acid production technologies in East and West last 100 years. Citric acid is commercially produced by large scale fermentation mostly using selected fungal or yeast strains in aerobe bioreactors and still remains one of the runners in industrial production of biotechnological bulk metabolites obtained by microbial fermentation since about 100 years, reflecting the historical development of modern biotechnology and fermentation process technology in East and West. Citric acid fermentation was first found as a fungal product in cultures of Penicillium glaucum on sugar medium by Wehmer in 1893. Citric acid is an important multifunctional organic acid with a broad range of versatile uses in household and industrial applications that has been produced industrially since the beginning of 20(th) century. There is a great worldwide demand for citric acid consumption due to its low toxicity, mainly being used as acidulant in pharmaceutical and food industries. Global citric acid production has reached 1.4 million tones, increasing annually at 3.5-4.0% in demand and consumption. Citric acid production by fungal submerged fermentation is still dominating, however new perspectives like solid-state processes or continuous yeast processes can be attractive for producers to stand in today's strong competition in industry. Further perspectives aiming in the improvement of citric acid production are the improvement of citric acid producing strains by classical and modern mutagenesis and selection as well as downstream processes. Many inexpensive by-products and residues of the agro-industry (e.g. molasses, glycerin etc.) can be economically utilized as substrates in the production of citric acid, especially in solid-state fermentation, enormously reducing production costs and minimizing environmental problems. Alternatively, continuous processes utilizing yeasts which reach 200-250 g/l citric acid can stand in today

  18. Microbial production of tenuazonic acid analogues. (United States)

    Gatenbeck, S; Sierankiewicz, J


    The fungus Alternaria tenuis normally produces tenuazonic acid (3-acetyl-5-secbutyltetramic acid). On supplementation of the culture substrate with l-valine and l-leucine, the organism formed two new tetramic acids, 3-acetyl-5-isopropyltetramic acid and 3-acetyl-5-isobutyltetramic acid, respectively. l-Phenylalanine was not utilized by the organism as a tetramic acid precursor.

  19. 49 CFR 173.158 - Nitric acid. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as...

  20. Fatty acids and cardiovascular disease. (United States)

    Lecerf, Jean-Michel


    Fatty acids have been classified into "good" or "bad" groups according to their degree of unsaturation or whether they are "animal fat" or "vegetable fat". Today, it appears that the effects of fatty acids are complex and vary greatly according to the dose and the nature of the molecule. Monounsaturated fatty acids are still considered as having a "neutral" status, but any benefits may be related to the chemical environment of the source food or the associated overall food pattern. Controversy surrounds omega-6 polyunsaturated fatty acids, because even though they lower LDL cholesterol levels, excessive intakes do not appear to be correlated with cardiovascular benefit. The omega-3 fatty acids are known to exert cardiovascular protective effects. Dairy fat and its cardiovascular impact are being evaluated. This review examines the existing literature on the relationships between the different fatty acids and cardiovascular disease.