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Sample records for 2-methylquinoline

  1. Biodegradation of 2-methylquinoline by Enterobacter aerogenes TJ-D isolated from activated sludge.

    Wang, Lin; Li, Yongmei; Duan, Jingyuan

    2013-07-01

    Bacterial strain Enterobacter aerogenes TJ-D capable of utilizing 2-methylquinoline as the sole carbon and energy source was isolated from acclimated activated sludge under denitrifying conditions. The ability to degrade 2-methylquinoline by E. aerogenes TJ-D was investigated under denitrifying conditions. Under optimal conditions of temperature (35 degrees C) and initial pH 7, 2-methylquinoline of 100 mg/L was degraded within 176 hr. The degradation of 2-methylquinoline by E. aerogenes TJ-D could be well described by the Haldane model (R2 > 0.91). During the degradation period of 2-methylquinoline (initial concentration 100 mg/L), nitrate was almost completely consumed (the removal efficiency was 98.5%), while nitrite remained at low concentration (ethyl-benzenamine, N-butyl-benzenamine, N-ethyl-benzenamine and 2,6-diethyl-benzenamine were metabolites produced during the degradation. The degradation pathway of 2-methylquinoline by E. aerogenes TJ-D was proposed. 2-Methylquinoline is initially hydroxylated at C-4 to form 2-methyl-4-hydroxy-quinoline, and then forms 2-methyl-4-quinolinol as a result of tautomerism. Hydrogenation of the heterocyclic ring at positions 2 and 3 produces 2,3-dihydro-2-methyl-4-quinolinol. The carbon-carbon bond at position 2 and 3 in the heterocyclic ring may cleave and form 2-ethyl-N-ethyl-benzenamine. Tautomerism may result in the formation of 2,6-diethyl-benzenamine and N-butyl-benzenamine. 4-Ethyl-benzenamine and N-ethyl-benzenamine were produced as a result of losing one ethyl group from the above molecules. PMID:24218841

  2. Bis(2-methylquinolin-8-olato-κ2N,O)lead(II)

    Gholamhossein Mohammadnezhad; Ali Reza Ghanbarpour; Amini, Mostafa M.; Seik Weng Ng

    2010-01-01

    The PbII atom in the title compound, [Pb(C10H8NO)2], is chelated by two oxine (2-methylquinolin-8-olate) anions in a Ψ-trigonal–bipyramidal geometry; the N atoms occupy the axial sites. The molecule lies about a twofold rotation axis.

  3. Bis(2-methylquinolin-8-olato-κ2N,Olead(II

    Gholamhossein Mohammadnezhad

    2010-05-01

    Full Text Available The PbII atom in the title compound, [Pb(C10H8NO2], is chelated by two oxine (2-methylquinolin-8-olate anions in a Ψ-trigonal–bipyramidal geometry; the N atoms occupy the axial sites. The molecule lies about a twofold rotation axis.

  4. 8-Hydroxy-2-methylquinolinium diiodido(2-methylquinolin-8-olato-κ2N,Ozincate

    Ezzatollah Najafi

    2011-09-01

    Full Text Available The reaction of 2-methyl-8-hydroxyquinoline and zinc iodide in acetonitrile affords the title salt, (C10H10NO[Zn(C10H8NOI2], in which the ZnII ion is coordinated by a N,O-chelating 2-methylquinolin-8-olate ligand and two iodide ligands in a distorted tetrahedral geometry. The cation is linked to the anion by an O—H...O hydrogen bond.

  5. Noncovalent-bonded 1D-3D supramolecular architectures from 2-methylquinoline/quinoline with monocarboxylic acid and dicarboxylic acid

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

    2014-10-01

    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.

  6. Ab initio, density functional theory and structural studies of 4-amino-2-methylquinoline

    Arjunan, V.; Saravanan, I.; Ravindran, P.; Mohan, S.

    2009-10-01

    The Fourier transform infrared (FTIR) and FT-Raman spectra of 4-amino-2-methylquinoline (AMQ) have been recorded in the range 4000-400 and 4000-100 cm -1, respectively. The experimental vibrational frequency was compared with the wavenumbers obtained theoretically by ab initio HF and DFT-B3LYP gradient calculations employing the standard 6-31G** and high level 6-311++G** basis sets for optimised geometry of the compound. The complete vibrational assignment and analysis of the fundamental modes of the compounds were carried out using the experimental FTIR and FT-Raman data, and quantum mechanical studies. The geometry and normal modes of vibration obtained from the HF and DFT methods are in good agreement with the experimental data. The potential energy distribution of the fundamental modes was calculated with ab initio force fields utilising Wilson's FG matrix method. The NH -π interactions and the influence of amino and methyl groups on the skeletal modes are investigated.

  7. 8-Hydroxy-2-methylquinolinium dichlorido(2-methylquinolin-8-olato-κ2N,Ozincate acetonitrile disolvate

    Ezzatollah Najafi

    2011-09-01

    Full Text Available The reaction of 2-methyl-8-hydroxyquinoline and zinc chloride in acetonitrile affords the title solvated salt, (C10H10NO[Zn(C10H8NOCl2]·2CH3CN, in which the ZnII atom is coordinated by an N,O-chelating 2-methylquinolin-8-olate ligand and two chloride ligands in a distorted tetrahedral geometry. The cation is linked to the heterocyclic anion by an O—H...O hydrogen bond and the quinolinium H atom forms a intermolecular N—H...N hydrogen bond with one of the acetonitrile solvent molecules.

  8. 8-Hydroxy-2-methylquinolinium dibromido(2-methylquinolin-8-olato-κ2N,Ozincate acetonitrile monosolvate

    Ezzatollah Najafi

    2011-09-01

    Full Text Available The reaction of 2-methyl-8-hydroxyquinoline and zinc bromide in acetonitrile affords the title solvated salt, (C10H10NO[ZnBr2(C10H8NO]·CH3CN, in which the ZnII ion is coordinated by a N,O-chelating 2-methylquinolin-8-olate ligand and two bromide ligands in a distorted tetrahedral geometry. The cation is linked to the anion by an O—H...O hydrogen bond and the quinolinium H atom forms an intermolecular N—H...N hydrogen bond with the acetonitrile solvent molecule.

  9. Synthesis, electrochemical, spectrophotometric and potentiometric studies of two azo-compounds derived from 4-amino-2-methylquinoline in ethanolic-aqueous buffered solutions

    El-Attar, Mona A.; Ghoneim, Mohamed M. [Analytical Chemistry Research Unit, Chemistry Department, Tanta University (Egypt); Ismail, Iqbal M., E-mail: maema.2011@yahoo.com [Chemistry Department, Faculty of Science, King Abdul Aziz University, Jeddah (Saudi Arabia)

    2012-08-15

    Two azo-compounds, 2-methyl-4-(5-amino-2-hydroxy-phenylazo)-quinoline (2) and 2-methyl-4-(2-hydroxy-5-nitrophenylazo)-quinoline, derived from 4-amino-2-methylquinoline were synthesized. Their chemical structures were characterized and confirmed by means of elemental chemical analysis, infrared (IR) spectroscopy, {sup 1}H nuclear magnetic resonance (NMR) and mass spectrometry (MS). The electrochemical behavior of the starting compound (4-amino-2-methylquinoline) and of the two synthesized azo-derivatives was studied at the mercury electrode in the B-R universal buffer at various pH values (2-11.5) containing 40% (v/v) ethanol using dc-polarography, cyclic voltammetry and controlled-potential coulometry. Their electrode reaction pathways were elucidated and discussed. The dissociation constants (pKa) of the examined compounds, stability constants and stoichiometry of their complexes in solution with some transition metal ions (Co(II), Ni(II), Cu(II), La(III) and UO{sup 2+}{sub 2}) were determined. (author)

  10. 2-甲基-8-羟基喹啉镓配合物的合成及发光性能研究%Synthesis and photoluminescent characteristics of 8-hydroxy-2-methylquinoline gallium

    孙春燕; 刘旭光; 陶鹏; 陈柳青

    2013-01-01

    8-Hydroxy-2-methylquinoline gallium(Ga(mhq)3) was synthesized, and its molecular structure was characterized by FT-IR spectrometry and : H NMR techniques. Its optical gap and photocurrent properties were investigated by UV-Vis absorption spectrometry, cyclic voltammetry, fluorescent emission spectrometry and electroluminescent spectrometry. Experimental results show that its optical gap is about 3. 10 eV, as determined from its UV-Vis absorption edge. Its UV absorption bands were at 259 and 365 nm. Ga(mhq)3 emitted intensive blue-green fluorescence at peak wavelength of 496 and 472 nm in THF solution and powder state, respectively. Finally, devices using Ga(mhq)3 as the emissive layer were fabricated and investigated. The device A with configuration of ITO/NPB(50nm)/Ga(mhq)3 (30nm)/LiF(lnm)/Al(100nm) showed maximum emission peak at 508nm and the maximum brightness of 901. 5 cd/m2, after optimization by introducing electron-transporting material Alq3, brightness can reach 4339cd/m2.%合成了2-甲基-8-羟基喹啉镓配合物(Ga(mhq)3),通过红外光谱、氢核磁谱确认其结构,进一步通过紫外-可见吸收光谱、循环伏安曲线、荧光发射光谱和电致发光光谱表征了其光学带隙及发光性质.实验结果表明Ga(mhq)3紫外吸收峰在259和365nm处,由紫外吸收得到光学带隙为3.10eV.在四氢呋喃溶液中,416nm激发下,荧光发射峰在496nm,为蓝绿色荧光;在360nm波长的激发下,Ga(mhq)3粉末发射峰在472nm处,属蓝绿光发射.将其做成器件A:ITO/NPB(50nm)/Ga (mhq)3 (30nm)/LiF(1nm)/Al(100nm),得到最大亮度为901.5cd/m2,最大发射波长为508nm.加入电子传输层Alq3对器件A进行优化后,最大亮度达到4339cd/m2.

  11. Cu-Pd/γ-Al2O3催化硝基苯和乙醇反应一锅法合成2-甲基喹啉%Cu-Pd/γ-Al2O3 catalyzed one-pot synthesis of 2-methylquinoline from nitrobenzene and ethanol

    丰枫; 项益智; 汪小华; 马磊; 卢春山; 张群峰; 许孝良; 李小年

    2011-01-01

    在5%Cu-5%Pd/Y-A12O3催化剂作用下,由硝基苯和乙醇反应一锅法合成了2-甲基喹啉.实现了乙醇与硝基苯转移加氢、乙醛缩合、苯胺与不饱和醛加成、脱水环化、脱氢等多步反应的耦合.极大地简化了2-甲基喹啉的合成工艺.相比较传统的化学合成方法,由于避免了使用无机酸碱或均相金属络合物作为催化剂,该方法环境更加友好,解决了均相金属络合物催化剂分离、回收困难的问题.在优化的反应条件:使用1 g催化剂,硝基苯15mL,乙醇60mL,水30 mL,T=453 K,P=3.5 MPa,反应时间为12 h时,2-甲基喹啉的收率达66.4%.%One-pot synthesis of 2-methylquoinline from nitrobenzene and ethanol was realized over 5%Cu-5%Pd/y-A12O3 catalyst. The reactions of hydrogen transfer hydrogenation from ethanol to nitrobenzene, aldol-condensation of aldehyde, Michae-addition of aniline and unsaturated aldehydes, dehydration-cyclization, and dehydrogenation are combined successfully, which thus significantly simplified the production procedure of 2-methylquinoline. In comparison with the traditional chemical synthesis routes, the use of inorganic acid or homogeneous metal complex as the catalyst was eliminated. Therefore, this method is more environmentally friendly, or can solve the problems of separation and recovery of homogeneous metal complex catalyst. Under the optimal reaction conditions: 1 g 5%Cu-5%Pd/Y-Al2O3 catalyst, 15 mL nitrobenzene, 60 mL ethanol, 30 mL water, T= 453 K, P = 3.5 Mpa, and 12 h reaction time, the yield of 2-methylquinoline as high as 66.4% was obtained.

  12. 8-Hydroxy-2-methylquinolinium diiodido(2-methylquinolin-8-olato-κ2N,Ozincate(II methanol monosolvate

    Seik Weng Ng

    2010-10-01

    Full Text Available The anion of the title salt, (C10H10NO[Zn(C10H8NOI2]·CH3OH, has its metal atom N,O-chelated by the deprotonated 2-methyl-8-hydroxyquinoline ligand. The hydroxy unit of the cation is a hydrogen-bond donor to the alkoxide O atom of the tetrahedrally coordinated anion, whereas the ammonium cation acts as a hydrogen-bond donor to the methanolic O atom. In the crystal, adjacent ion pairs and solvent molecules are linked by a methanol–halogen O—H...I hydrogen bond, generating a chain running along the a axis.

  13. 8-Hydroxy-2-methylquinolinium dichlorido(2-methylquinolin-8-olato-κ2N,Ozincate(II methanol solvate

    Seik Weng Ng

    2009-05-01

    Full Text Available The reaction of zinc chloride and 2-methyl-8-hydroxyquinoline in methanol yielded the title monosolvated salt, (C10H10NO[ZnCl2(C10H8NO]·CH3OH, which has the Zn atom within a distorted Cl2NO tetrahedral coordination geometry. Supramolecular chains feature in the crystal structure, comprising all components of the structure stabilized by a combination of O—H...O, N—H...O and O—H...Cl hydrogen bonding.

  14. 8-Hydroxy-2-methylquinolinium dibromido(2-methylquinolin-8-olato-κ2N,Ozincate(II methanol monosolvate

    Seik Weng Ng

    2010-10-01

    Full Text Available The anion of the title salt, (C10H10NO[ZnBr2(C10H8NO]·CH3OH, has its metal atom N,O-chelated by the deprotonated 2-methyl-8-hydroxyquinoline ligand. The hydroxy unit of the cation is a hydrogen-bond donor to the alkoxide O atom of the tetrahedrally coordinated anion, whereas the ammonium cation is a hydrogen-bond donor to the methanolic O atom. In the crystal, adjacent ion pairs and solvent molecules are linked by a methanol–halogen O—H...Br hydrogen bond, generating a chain running along the a axis.

  15. Bis(μ-2-methylquinolin-8-olato-κ3N,O:O;κ3O:N,O-bis[(acetato-κO(methanol-κOzinc(II

    Seik Weng Ng

    2009-05-01

    Full Text Available The reaction of zinc acetate and 2-methyl-8-hydroxyquinoline in methanol yielded the centrosymmetric dinuclear title compound, [Zn2(C10H8NO2(CH3CO22(CH3OH2], which has the Zn atom within a distorted NO4 trigonal–bipyramidal coordination geometry. Methanol–acetate O—H...O hydrogen bonds link the dinculear units into a linear supramolecular chain extending parallel to [100].

  16. CHEMISTRY OF THIENOPYRIDINES .39. SYNTHESIS OF [1]BENZOTHIENO[2,3-H]ISOQUINOLINE AND RELATED STUDIES

    KLEMM, LH; SEVERNS, B; WYNBERG, H

    1991-01-01

    Benzo[b]thiophene-2-carboxaldehyde undergoes condensation with 4-methylpyridine and with 2-methylquinoline to produce trans-diarylethenes (52% and 76%, respectively). The former alkene photocyclizes in cyclohexane to yield [1]benzo[2,3-h]isoquinoline (35%), while the latter alkene does not give succ

  17. Phosphorescent emissions of phosphine copper(I) complexes bearing 8-hydroxyquinoline carboxylic acid analogue ligands

    The pseudotetrahedral complexes of [Cu(PPh3)2(L)], where L=8-hydroxy-2-methylquinoline-7-carboxylic acid (1), 8-hydroxy-2,5-dimethylquinoline-7-carboxylic acid (2) or 5-chloro-8-hydroxy-2-methylquinoline-7-carboxylic acid (3) have been synthesized and structurally characterized by X-ray crystallography. Their properties have been examined through combinations of IR, NMR, electronic absorption spectroscopy and cyclic voltammetry. The complexes exhibit extraordinary photophysical properties. Complex (1) in solid state exhibits an emission quantum yield of 4.67% and an excited life time of 1.88 ms (frozen DCM solution up to 6.7 ms). When dissolved in a coordinating solvent (acetonitrile) the charge transfer emission was quenched on a microsecond scale. - Highlights: • Synthesis of copper(I) complexes with 8-hydroxyquinoline carboxylic acid ligands. • Very long lived phosphorescent copper(I) complexes. • [Cu(PPh3)2(L)] where L=8-hydroxy-2-methylquinoline-7-carboxylic acid luminesce in the solid state exhibits extremely long lifetime on millisecond scale (1.9 ms). • In frozen MeOH:EtOH solution lifetime increases to 7 ms. • Quantum efficiency equal to 4.7%

  18. Phosphorescent emissions of phosphine copper(I) complexes bearing 8-hydroxyquinoline carboxylic acid analogue ligands

    Małecki, Jan G., E-mail: gmalecki@us.edu.pl [Department of Crystallography, Institute of Chemistry, University of Silesia, Szkolna 9 street, 40-006 Katowice (Poland); Łakomska, Iwona, E-mail: iwolak@chem.umk.pl [Department of Chemistry, Nicolaus Copernicus University, Toruń (Poland); Maroń, Anna [Department of Crystallography, Institute of Chemistry, University of Silesia, Szkolna 9 street, 40-006 Katowice (Poland); Szala, Marcin [Institute of Chemistry, University of Silesia, ul. Szkolna 9, 40-006 Katowice (Poland); Fandzloch, Marzena [Department of Chemistry, Nicolaus Copernicus University, Toruń (Poland); Nycz, Jacek E., E-mail: jacek.nycz@us.edu.pl [Institute of Chemistry, University of Silesia, ul. Szkolna 9, 40-006 Katowice (Poland)

    2015-05-15

    The pseudotetrahedral complexes of [Cu(PPh{sub 3}){sub 2}(L)], where L=8-hydroxy-2-methylquinoline-7-carboxylic acid (1), 8-hydroxy-2,5-dimethylquinoline-7-carboxylic acid (2) or 5-chloro-8-hydroxy-2-methylquinoline-7-carboxylic acid (3) have been synthesized and structurally characterized by X-ray crystallography. Their properties have been examined through combinations of IR, NMR, electronic absorption spectroscopy and cyclic voltammetry. The complexes exhibit extraordinary photophysical properties. Complex (1) in solid state exhibits an emission quantum yield of 4.67% and an excited life time of 1.88 ms (frozen DCM solution up to 6.7 ms). When dissolved in a coordinating solvent (acetonitrile) the charge transfer emission was quenched on a microsecond scale. - Highlights: • Synthesis of copper(I) complexes with 8-hydroxyquinoline carboxylic acid ligands. • Very long lived phosphorescent copper(I) complexes. • [Cu(PPh{sub 3}){sub 2}(L)] where L=8-hydroxy-2-methylquinoline-7-carboxylic acid luminesce in the solid state exhibits extremely long lifetime on millisecond scale (1.9 ms). • In frozen MeOH:EtOH solution lifetime increases to 7 ms. • Quantum efficiency equal to 4.7%.

  19. Fluorescent sensor for selective detection of Al(3+) based on quinoline-coumarin conjugate.

    Qin, Jing-can; Li, Tian-rong; Wang, Bao-dui; Yang, Zheng-yin; Fan, Long

    2014-12-10

    A fluorescence probe, 8-formyl-7-hydroxyl-4-methyl coumarin - (2'-methylquinoline-4-formyl) hydrazone (L) has been synthesized. The chemosensor is found preferential binding to Al(3+) in presence of other competitive ions with associated changes in its optical and fluorescence spectra behavior. Upon addition of Al(3+) to a solution of L, it shows 200-fold enhancement of fluorescence intensity which might be attributed to form a 2:1 stoichiometry of the binding mode of LAl(III) and the chelation enhanced fluorescence (CHEF) process at 479nm in ethanol. The lowest detection limit for Al(3+) is determined as 8.2×10(-7)M. PMID:24929313

  20. 8-Hydroxy-2-methylquinolinium tetrachlorido(quinolin-8-olato-κ2N,Ostannate(IV

    Ezzatollah Najafi

    2012-06-01

    Full Text Available The reaction of 8-hydroxyquinoline, 2-methylquinolin-8-ol and stannic chloride yields the protonated 8-hydroxy-2-methylquinolinium species. In the title salt, (C10H10NO[Sn(C9H6NOCl4], the SnIV cation is N,O-chelated by the quinolin-8-olate anion and is further coordinated by four Cl− anions in a distorted cis-SnNOCl4 octahedral geometry. In the crystal, the cation is linked to the anion by an O—H...O hydrogen bond.

  1. Degradation pathway of quinolines in a biofilm system under denitrifying conditions

    Johansen, S.S.; Arvin, E.; Mosbaek, H. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Environmental Science and Engineering; Hansen, A.B. [National Environmental Research Inst., Roskilde (Denmark). Dept. of Environmental Chemistry

    1997-09-01

    This article reports for the first time the degradation pathways of quinoline, isoquinoline, and methylquinolines by a mixed culture in a biofilm under nitrate-reducing conditions. A simple reverse-phase high-performance liquid chromatography method using ultraviolet detection at 223 nm for determination of seven quinoline analogues and 15 metabolites was developed, and gas chromatography--mass spectrometry and thin-layer chromatography analyses were used for identification. The inhibition of nitrification by the parent compounds and their degradation products was assessed by a nitrification toxicity test called MINNTOX. Quinoline and 3-, 4-, 6-, and 8-methylquinoline were all transformed by hydroxylation into their 2-hydroxyquinoline analogues (2-quinolinones), and isoquinoline was transformed into 1-hydroxyisoquinoline. 2-Methylquinoline was not transformed by this microcosm, likely due to the blockage at position 2 by the methyl group. The hydroxylated metabolites of isoquinoline and quinolines methylated at the heterocyclic ring were not transformed further, whereas metabolites of quinoline and quinolines methylated at the homocyclic ring were hydrogenated at position 3 and 4, and the resulting 3,4-dihydro-2-quinolinone analogues accumulated. Of these metabolites, only 3,4-dihydro-2-quinolinone from the degradation of quinoline was further transformed into unidentified products. All quinolines and their metabolites had inhibiting effects on the nitrifying bacteria at the same level (ppm) in the applied bioassay, indicating that the inhibition of the compounds was not influenced by the initial transformation reactions.

  2. Structural and spectroscopic characterizations of tetra-nuclear niobium(V) complexes of quinolinol derivatives

    Amini, Mostafa M.; Fazaeli, Yousef; Mohammadnezhad, Gholamhossein; Khavasi, Hamid Reza

    2015-06-01

    Reactions between niobium ethoxide and 8-hydroxy-2-methylquinoline or 5-chloro-8-hydroxyquinoline have been explored. Two new tetranuclear heteroleptic niobium complexes containing oxo, ethoxo, and quinolinate chelate rings have been synthesized and characterized by 1H, 13C and 93Nb NMR, UV-Vis, and FT-IR spectroscopies, and single-crystal X-ray diffraction. The molecular structures of the niobium complexes, [Nb4(μ-O)4(μ-OEt)2(ONC10H8)2(OEt)8] (I) and [Nb4(μ-O)4(μ-OEt)2(ONC9H5Cl)2(OEt)8] (II), are composed of a pair of edge-sharing bioctahedral moieties in which connected via two almost linear oxo-bridges, with a large difference in the NbO distances. Single-crystal structures showed both complexes are centrosymmetric and contain two distinct Nb centers, and results confirmed by observation of two niobium signals in the 93Nb NMR spectra of complexes.

  3. Detection of methylquinoline transformation products in microcosm experiments and in tar oil contaminated groundwater using LC-NMR.

    Reineke, Anne-Kirsten; Preiss, Alfred; Elend, Manfred; Hollender, Juliane

    2008-02-01

    N-heterocyclic compounds are known pollutants at tar oil contaminated sites. Here we report the degradation of methyl-, and hydroxy-methyl-substituted quinolines under nitrate-, sulfate- and iron-reducing conditions in microcosms with aquifer material of a former coke manufacturing site. Comparison of degradation potential and rate under different redox conditions revealed highest degradation activities under sulfate-reducing conditions, the prevailing conditions in the field. Metabolites of methylquinolines, with the exception of 2-methylquinolines, were formed in high amounts in the microcosms and could be identified by (1)H NMR spectroscopy as 2(1H)-quinolinone analogues. 4-Methyl-, 6-methyl-, and 7-methyl-3,4-dihydro-2(1H)-quinolinone, the hydrogenated metabolites in the degradation of quinoline compounds, were identified by high resolution LC-MS. Metabolites of methylquinolines showed persistence, although for the first time a transformation of 4-methylquinoline and its metabolite 4-methyl-2(1H)-quinolinone is described. The relevance of the identified metabolites is supported by the detection of a broad spectrum of them in groundwater of the field site using LC-NMR technique. LC-NMR allowed the differentiation of isomers and identification without reference compounds. A variety of methylated 2(1H)-quinolinones, as well as methyl-3,4-dihydro-2(1H)-quinolinone isomers were not identified before in groundwater. PMID:17936873

  4. Formation of blade and slot die coated small molecule multilayers for OLED applications studied theoretically and by XPS depth profiling

    Peters, Katharina; Raupp, Sebastian; Hummel, Helga; Bruns, Michael; Scharfer, Philip; Schabel, Wilhelm

    2016-06-01

    Slot die coaters especially designed for low material consumption and doctor blades were used to process small molecule solutions for organic light-emitting diodes (OLEDs). Optimum process parameters were developed for the large-scale coating techniques to generate stable single and multiple layers only a few nanometers thick. Achieving a multilayer architecture for solution-processed OLEDs is the most challenging step. X-ray photoelectron spectroscopy sputter depth profiling was performed to determine defined interfaces between coated organic layers. Commercially available small molecules NPB (N,N'-Di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine) and BAlq (Bis(8-hdroxy-2methylquinoline)-(4-phenylphenoxy)aluminum), originally developed for vacuum deposition, were used as hole, respectively electron transport material. Defined double-layers were processed with both scalable coating methods using the orthogonal solvent approach. The use of non-orthogonal solvents resulted in complete intermixing of the material. The results are explained by calculations of solubilities and simulating drying and diffusion kinetics of the small molecule solutions.

  5. Iron- and 4-hydroxy-2-alkylquinoline-containing periplasmic inclusion bodies of Pseudomonas aeruginosa: A chemical analysis

    Royt, P.W.; Honeychuck, R.V.; Pant, R.R.; Rogers, M.L.; Asher, L.V.; Lloyd, J.R.; Carlos, W.E.; Belkin, H.E.; Patwardhan, S.

    2007-01-01

    Dark aggregated particles were seen on pellets of iron-rich, mid-logarithmic phase Pseudomonas aeruginosa. Transmission electron microscopy of these cells showed inclusion bodies in periplasmic vacuoles. Aggregated particles isolated from the spent medium of these cells contained iron as indicated by atomic absorption spectroscopy and by electron paramagnetic resonance spectroscopy that revealed Fe3+. Scanning electron microscopy/energy dispersive X-ray analysis of whole cells revealed the presence of iron-containing particles beneath the surface of the cell, indicating that the isolated aggregates were the intracellular inclusion bodies. Collectively, mass spectroscopy and nuclear magnetic resonance spectroscopy of the isolated inclusion bodies revealed the presence of 3,4-dihydroxy-2-heptylquinoline which is the Pseudomonas quinolone signaling compound (PQS) and an iron chelator; 4-hydroxy-2-heptylquinoline (pseudan VII), which is an iron chelator, antibacterial compound and precursor of PQS; 4-hydroxy-2-nonylquinoline (pseudan IX) which is an iron chelator and antibacterial compound; 4-hydroxy-2-methylquinoline (pseudan I), and 4-hydroxy-2-nonylquinoline N-oxide. ?? 2006 Elsevier Inc. All rights reserved.

  6. Determination of drug-like properties of a novel antileishmanial compound: In vitro absorption, distribution, metabolism, and excretion studies

    Mondal Susanta

    2009-01-01

    Full Text Available In drug discovery research, the compounds should not only to be potent and selective but also must possess acceptable pharmacokinetic properties such as absorption, distribution, metabolism, and excretion (ADME to increase success rate in clinical studies. Objective: Exploration of drug-like properties of 2-(2-methylquinolin-4-ylamino-N-phenyl acetamide, a potent antileishmanial compound by performing some in vitro ADME experiments along with validation of such studies. Materials and Methods: Experimental protocols were established and validated for stability (in PBS pH7.4, simulated gastric and intestinal fluid, solubility, permeability, distribution coefficient (Log D, plasma protein binding and metabolism by rat liver microsomes by using spectrophotometer or HPLC. Methods were considered valid if the results of the standard compounds matched with reported results or within acceptable range or with proper ranking (high-medium-low. Results: The compound was found to be stable (>95% remaining in all stability studies and aqueous solubility was 299.7 ± 6.42 μM. The parallel artificial membrane permeability assay (PAMPA indicated its medium permeability (Log Pe = -5.53 ± 0.01. The distribution coefficients (Log D in octanol/PBS and cyclohexane/PBS systems were found to be 0.54 and -1.33, respectively. The plasma protein binding study by the equilibrium dialysis method was observed to be 78.82 ± 0.13% while metabolism by Phase-I enzymes for 1 hour at 37°C revealed that 36.07 ± 4.15% of the compound remained after metabolism. Conclusion: The methods were found to be very useful for day-to-day ADME studies. All the studies with the antileishmanial compound ascertained that the compound bears optimum pharmacokinetic properties to be used orally as a potential drug for the treatment of leishmaniasis.

  7. Dinuclear Zinc(II) Macrocyclic Complex as Receptor for Selective Fluorescence Sensing of Pyrophosphate.

    Mesquita, Lígia M; André, Vânia; Esteves, Catarina V; Palmeira, Tiago; Berberan-Santos, Mário N; Mateus, Pedro; Delgado, Rita

    2016-03-01

    A new diethylenetriamine-derived macrocycle known as L, bearing 2-methylquinoline arms and containing m-xylyl spacers, was prepared in good yield by a one-pot [2 + 2] Schiff base condensation procedure, followed by reduction with sodium borohydride. Up to now this is the first hexaazamacrocycle with appended fluorophore units. Single-crystal X-ray diffraction determination of the dinuclear zinc(II) complex of L showed that metal centers are located at about 7.20(2) Å from one another. This complex exhibits only weak fluorescence in aqueous solution, but the addition of 1 equiv of pyrophosphate (PPi) caused a 21-fold enhancement of the fluorescence intensity. The sensor response is linear up to a value of 10 μM HPPi(3-) and has a detection limit of 300 nM. The receptor behaves as a highly selective sensor for pyrophosphate as other anions, including phosphate, phenylphosphate (PhP), adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP), failed to induce any fluorescence change and practically do not affect the fluorescence intensity of the sensor in the presence of HPPi(3-). Competition titrations carried out in aqueous solution at pH 7.4 [in 20 mM 3-(N-morpholino)propanesulfonic acid (MOPS) buffer] by spectrofluorometry revealed a high association constant value of 6.22 log units for binding of PPi by the dinuclear zinc(II) receptor, one of the highest reported values for colorimetric/fluorometric sensors able to work under real aqueous physiological conditions, while association constant values for binding of the other phosphorylated substrates are in the 5.51-4.03 log unit range. PMID:26871612

  8. Complete genome sequence and metabolic potential of the quinaldine-degrading bacterium Arthrobacter sp. Rue61a

    Niewerth Heiko

    2012-10-01

    Full Text Available Abstract Background Bacteria of the genus Arthrobacter are ubiquitous in soil environments and can be considered as true survivalists. Arthrobacter sp. strain Rue61a is an isolate from sewage sludge able to utilize quinaldine (2-methylquinoline as sole carbon and energy source. The genome provides insight into the molecular basis of the versatility and robustness of this environmental Arthrobacter strain. Results The genome of Arthrobacter sp. Rue61a consists of a single circular chromosome of 4,736,495 bp with an average G + C content of 62.32%, the circular 231,551-bp plasmid pARUE232, and the linear 112,992-bp plasmid pARUE113 that was already published. Plasmid pARUE232 is proposed to contribute to the resistance of Arthrobacter sp. Rue61a to arsenate and Pb2+, whereas the linear plasmid confers the ability to convert quinaldine to anthranilate. Remarkably, degradation of anthranilate exclusively proceeds via a CoA-thioester pathway. Apart from quinaldine utilization, strain Rue61a has a limited set of aromatic degradation pathways, enabling the utilization of 4-hydroxy-substituted aromatic carboxylic acids, which are characteristic products of lignin depolymerization, via ortho cleavage of protocatechuate. However, 4-hydroxyphenylacetate degradation likely proceeds via meta cleavage of homoprotocatechuate. The genome of strain Rue61a contains numerous genes associated with osmoprotection, and a high number of genes coding for transporters. It encodes a broad spectrum of enzymes for the uptake and utilization of various sugars and organic nitrogen compounds. A. aurescens TC-1 is the closest sequenced relative of strain Rue61a. Conclusions The genome of Arthrobacter sp. Rue61a reflects the saprophytic lifestyle and nutritional versatility of the organism and a strong adaptive potential to environmental stress. The circular plasmid pARUE232 and the linear plasmid pARUE113 contribute to heavy metal resistance and to the ability to degrade

  9. Anxiolytic- and antidepressant-like profile of a new CRF1 receptor antagonist, R278995/CRA0450.

    Chaki, Shigeyuki; Nakazato, Atsuro; Kennis, Ludo; Nakamura, Masato; Mackie, Claire; Sugiura, Masayuki; Vinken, Petra; Ashton, David; Langlois, Xavier; Steckler, Thomas

    2004-02-01

    1-[8-(2,4-dichlorophenyl)-2-methylquinolin-4-yl]-1,2,3,6-tetrahydropyridine-4-carboxamide benzenesulfonate (R278995/CRA0450) is a newly synthesized corticotropin-releasing factor subtype 1 (CRF(1)) receptor antagonist. In the present study, in vitro and in vivo pharmacological profiles of R278995/CRA0450 were investigated. R278995/CRA0450 showed high affinity for recombinant and native CRF(1) receptors without having affinity for the CRF(2) receptor. R278995/CRA0450 attenuated CRF-induced cyclic AMP formation in AtT-20 cells and CRF-induced forepaw treading in gerbils, indicating that R278995/CRA0450 is an antagonist of the CRF(1) receptor. In addition to CRF(1) receptor antagonism, R278995/CRA0450 showed high affinity for the sigma(1) receptor, and attenuated (+)-SKF10,047-induced head-weaving behavior, suggesting sigma(1) receptor antagonism. R278995/CRA0450 showed dose-dependent in vivo occupancy when assessed by ex vivo receptor binding, indicating good brain penetration. R278995/CRA0450 did not alter spontaneous anxiety when tested in the rat elevated plus maze (up to 3 mg/kg, p.o.) or lick suppression test (up to 10 mg/kg, i.p.). However, potent anxiolytic-like properties were observed in rats subjected to swim stress prior to testing on the elevated plus-maze, indicating activity primarily in tests taxing stress-induced anxiety. R278995/CRA0450 was inactive in mouse tail suspension, rat forced swim and rat differential-reinforcement-of-low-rate 72-s (DRL72), while it showed dose-dependent antidepressant-like effects in the rat learned helplessness paradigm and the olfactory bulbectomy model, demonstrating activity in a subset of animal models of depression associated with subchronic stress exposure. No or only mild effects were seen in tests of locomotor activity, motor coordination and sedation. These results indicate that R278995/CRA0450 is an orally active CRF(1) and sigma(1) receptor antagonist with potent anxiolytic-like and antidepressant

  10. Transport of creosote compounds in a large, intact, macroporous clayey till column

    Broholm, Kim; Jørgensen, Peter R.; Hansen, Asger B.; Arvin, Erik; Hansen, Martin

    1999-10-01

    The transport in macroporous clayey till of bromide and 25 organic compounds typical of creosote was studied using a large intact soil column. The organic compounds represented the following groups: polycyclic aromatic hydrocarbons (PAHs), phenolic compounds, monoaromatic hydrocarbons (BTEXs), and heterocyclic compounds containing oxygen, nitrogen or sulphur in the aromatic ring structure (NSO-compounds). The clayey till column (0.5 m in height and 0.5 m in diameter) was obtained from a depth of 1-1.5 m at an experimental site located on the island of Funen, Denmark. Sodium azide was added to the influent water of the column to prevent biodegradation of the studied organic compounds. For the first 24 days of the experiment, the flow rate was 219 ml day -1 corresponding to an infiltration rate of 0.0011 m day -1. At this flow rate, the effluent concentrations of bromide and the organic compounds increased very slowly. The transport of bromide and the organic compounds were successfully increased by increasing the flow rate to 1353 ml day -1 corresponding to 0.0069 m day -1. The experiment showed that the transport of low-molecular-weight organic compounds was not retarded relative to bromide. The high-molecular-weight organic compounds were retarded significantly. The influence of sorption on the transport of the organic compounds through the column was evaluated based on the observed breakthrough curves. The observed order in the column experiment was, with increasing retardation, the following: benzene=pyrrole=toluene= o-xylene= p-xylene=ethylbenzene=phenol=benzothiophene=benzofuran2-methylquinoline

  11. A selective orexin-1 receptor antagonist attenuates stress-induced hyperarousal without hypnotic effects.

    Bonaventure, Pascal; Yun, Sujin; Johnson, Philip L; Shekhar, Anantha; Fitz, Stephanie D; Shireman, Brock T; Lebold, Terry P; Nepomuceno, Diane; Lord, Brian; Wennerholm, Michelle; Shelton, Jonathan; Carruthers, Nicholas; Lovenberg, Timothy; Dugovic, Christine

    2015-03-01

    Orexins (OXs) are peptides produced by perifornical (PeF) and lateral hypothalamic neurons that exert a prominent role in arousal-related processes, including stress. A critical role for the orexin-1 receptor (OX1R) in complex emotional behavior is emerging, such as overactivation of the OX1R pathway being associated with panic or anxiety states. Here we characterize a brain-penetrant, selective, and high-affinity OX1R antagonist, compound 56 [N-({3-[(3-ethoxy-6-methylpyridin-2-yl)carbonyl]-3-azabicyclo[4.1.0]hept-4-yl}methyl)-5-(trifluoromethyl)pyrimidin-2-amine]. Ex vivo receptor binding studies demonstrated that, after subcutaneous administration, compound 56 crossed the blood-brain barrier and occupied OX1Rs in the rat brain at lower doses than standard OX1R antagonists GSK-1059865 [5-bromo-N-({1-[(3-fluoro-2-methoxyphenyl)carbonyl]-5-methylpiperidin-2-yl}methyl)pyridin-2-amine], SB-334867 [1-(2-methyl-1,3-benzoxazol-6-yl)-3-(1,5-naphthyridin-4-yl)urea], and SB-408124 [1-(6,8-difluoro-2-methylquinolin-4-yl)-3-[4-(dimethylamino)phenyl]urea]. Although compound 56 did not alter spontaneous sleep in rats and in wild-type mice, its administration in orexin-2 receptor knockout mice selectively promoted rapid eye movement sleep, demonstrating target engagement and specific OX1R blockade. In a rat model of psychological stress induced by cage exchange, the OX1R antagonist prevented the prolongation of sleep onset without affecting sleep duration. In a rat model of panic vulnerability (involving disinhibition of the PeF OX region) to threatening internal state changes (i.e., intravenous sodium lactate infusion), compound 56 attenuated sodium lactate-induced panic-like behaviors and cardiovascular responses without altering baseline locomotor or autonomic activity. In conclusion, OX1R antagonism represents a novel therapeutic strategy for the treatment of various psychiatric disorders associated with stress or hyperarousal states. PMID:25583879

  12. Tri- and tetra-dentate imine vanadyl complexes: synthesis, structure and ethylene polymerization/ring opening polymerization capability.

    Ma, Jing; Zhao, Ke-Qing; Walton, Mark; Wright, Joseph A; Hughes, David L; Elsegood, Mark R J; Michiue, Kenji; Sun, Xinsen; Redshaw, Carl

    2014-11-28

    Reaction of the ligand 2,4-tert-butyl-6-[(2-methylquinolin-8-ylimino)methyl]phenol (L(1)H) with [VOCl3] in the presence of triethylamine afforded the complex [VOCl2L(1)] (1), whereas use of [VO(OnPr)3] led to the isolation of [VO2L(1)] (2) or [VO2L(1)]·2/3MeCN (2·2/3MeCN). Reaction of 2-((2-(1H-benzo[d]imidazol-2-yl)quinolin-8-ylimino)methyl)-4,6-R(1),R(2)-phenols (R(1) = R(2) = (t)Bu; L(2)H), (R(1) = R(2) = Me; L(3)H) or (R(1) = Me, R(2) = Ad; L(4)H) with [VO(OnPr)3] afforded complexes of the type [L(2-4)VO] (where L(2) = 3, L(3) = 4, L(4) = 5). The molecular structures of 1 to 3 are reported; the metal centre adopts a distorted octahedral, trigonal bipyramidal or square-based pyramidal geometry respectively. In Schlenk line tests, all complexes have been screened as pre-catalysts for the polymerization of ethylene using diethylaluminium chloride (DEAC) as co-catalyst in the presence of ethyltrichloroacetate (ETA), and for the ring opening polymerization (ROP) of ε-caprolactone in the presence of benzyl alcohol. All pre-catalyst/DEAC/ETA systems are highly active ethylene polymerization catalysts affording linear polyethylene with activities in the range 3000-10,700 g (mol h bar)(-1); the use of methylaluminoxane (MAO) or modified MAO as co-catalyst led to poor or no activity. In a parallel pressure reactor, 3-5 have been screened as pre-catalysts for ethylene polymerization in the presence of either DEAC or DMAC (dimethylaluminium chloride) and ETA at various temperatures and for the co-polymerization of ethylene with propylene. The use of DMAC proved more promising with 3 achieving an activity of 63,000 g (mol h bar)(-1) at 50 °C and affording UHMWPE (M(w) ~ 2,000,000). In the case of the co-polymerization, the incorporation of propylene was 6.9-8.8 mol%, with 3 exhibiting the highest incorporation when using either DEAC or DMAC. In the case of the ring opening polymerization (ROP) of ε-caprolactone, systems employing complexes 1-5 were virtually inactive