Sample records for 2-methylquinoline

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

    Wang, Lin; Li, Yongmei; Duan, Jingyuan


    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 (< 0.62 mg/L) during the whole denitrification period. 1,2,3,4-Tetrahydro-2-methylquinoline, 4-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.

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

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


    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)

  3. Tautomer-selective derivatives of enolate, ketone and enaminone by addition reaction of picolyl-type anions with nitriles (United States)

    Bai, Jianliang; Wang, Peng; Cao, Wei; Chen, Xia


    We describe an efficient for the synthesis of compounds of tautomeric β-pyridyl/quinolyl-enol, -ketone, -enaminone, which were finally characterized by standard methods like NMR, IR or SCXRD. The addition reaction of lithiated intermediates of picoline, 2-ethylpyridine and 2-methylquinoline, respectively, with nitriles followed by acid hydrolysis afforded the corresponding tautomeric compounds of enol, ketone and emaminone. Interestingly, treatment of 2-methylpyridine or 2-ethylpyridine with nitriles, respectively, yielded mostly β-pyridyl ketone and enol tautomers without enaminones, while 2-methylquinoline with nitriles gave β-quinolyl ketone and enaminone tautomers without enols. The reaction of 2-benzylpyridine with nitriles was not available under the same conditions.


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    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

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

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    Małecki, Jan G., E-mail: [Department of Crystallography, Institute of Chemistry, University of Silesia, Szkolna 9 street, 40-006 Katowice (Poland); Łakomska, Iwona, E-mail: [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: [Institute of Chemistry, University of Silesia, ul. Szkolna 9, 40-006 Katowice (Poland)


    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%.

  6. GC/MS based identification of skunk spray maliciously deployed as "biological weapon" to harm civilians. (United States)

    Wennig, Robert; Schneider, Serge; Meys, François


    Our laboratory has been asked to elucidate the origin of a strong "toxic smell" present in a prominent politician's office, private house and motorcar. This stinky and pungent atmosphere has caused serious nausea and vomiting to several individuals. Urine samples were collected from the persons presenting symptoms of nausea for toxicological analysis. Drops, paper and cotton swabs of an oily liquid found at the implicated places were submitted by police to our laboratory for investigation. Methanol extracts of the drops were acetylated for gas chromatography/mass spectrometry (GC/MS) analysis in the electron impact mode; the cotton and paper swabs were analysed using headspace-gas chromatography/mass spectrometry (HS-GC/MS). The GC/MS analysis of the acetylated methanol extracts revealed that the major peaks of the chromatogram could be attributed to 2-methylquinoline, to 2-quinolinemethanethiol, to S-2-quinolinemethyl thioacetate, to 2-phenylethanethiol, to bis(E)-2-butenyl disulphide and to bis(3-methylbutyl) disulphide. Several volatile sulphur-containing compounds have been identified with the HS-GC/MS system. Detailed examination of the spectra as well as GC/MS analysis of commercially available skunk secret allowed us to relate the identified compounds to those present in the defence spray of skunks. No health sequels were observed for any of the persons implicated in this case.

  7. Involvement of the renal kallikrein-kinin system in K(+)-induced diuresis and natriuresis in anesthetized rats. (United States)

    Suzuki, T; Katori, M; Fujita, T; Kumagai, Y; Majima, M


    Intravenous infusion of a high-K(+) solution (67.5 mM KCl, 67.5 mM NaCl) to anesthetized rats increased urine volume by 47.6% after 60 min, compared with infusion of a Na(+) solution (135 mM NaCl). This treatment also increased urinary excretion of Na(+) by 32.2%, in parallel with an increase in excretion of K(+) or Cl(-). Urinary excretion of kallikrein increased within 60 min after the start of K(+) infusion. A bradykinin B(2) receptor antagonist, 8-[3-[N-[(E)-3-(6-acetamidopyridin-3-yl)acryloylglycyl]-N-me thylamino ]-2,6-dichlorobenzyloxy]-2-methylquinoline (FR173657; 1.0 mg/kg, i.v. ), inhibited the K(+)-induced diuresis and natriuresis by 41.0% and 26.7%, respectively. These results indicate that K(+) load induces diuresis and natriuresis through the renal kallikrein-kinin system in rats.

  8. Single cell kinase signaling assay using pinched flow coupled droplet microfluidics. (United States)

    Ramji, Ramesh; Wang, Ming; Bhagat, Ali Asgar S; Tan Shao Weng, Daniel; Thakor, Nitish V; Teck Lim, Chwee; Chen, Chia-Hung


    Droplet-based microfluidics has shown potential in high throughput single cell assays by encapsulating individual cells in water-in-oil emulsions. Ordering cells in a micro-channel is necessary to encapsulate individual cells into droplets further enhancing the assay efficiency. This is typically limited due to the difficulty of preparing high-density cell solutions and maintaining them without cell aggregation in long channels (>5 cm). In this study, we developed a short pinched flow channel (5 mm) to separate cell aggregates and to form a uniform cell distribution in a droplet-generating platform that encapsulated single cells with >55% encapsulation efficiency beating Poisson encapsulation statistics. Using this platform and commercially available Sox substrates (8-hydroxy-5-(N,N-dimethylsulfonamido)-2-methylquinoline), we have demonstrated a high throughput dynamic single cell signaling assay to measure the activity of receptor tyrosine kinases (RTKs) in lung cancer cells triggered by cell surface ligand binding. The phosphorylation of the substrates resulted in fluorescent emission, showing a sigmoidal increase over a 12 h period. The result exhibited a heterogeneous signaling rate in individual cells and showed various levels of drug resistance when treated with the tyrosine kinase inhibitor, gefitinib.

  9. Assessing Physicochemical Properties of Drug Molecules via Microsolvation Measurements with Differential Mobility Spectrometry. (United States)

    Liu, Chang; Le Blanc, J C Yves; Schneider, Bradley B; Shields, Jefry; Federico, James J; Zhang, Hui; Stroh, Justin G; Kauffman, Gregory W; Kung, Daniel W; Ieritano, Christian; Shepherdson, Evan; Verbuyst, Mitch; Melo, Luke; Hasan, Moaraj; Naser, Dalia; Janiszewski, John S; Hopkins, W Scott; Campbell, J Larry


    The microsolvated state of a molecule, represented by its interactions with only a small number of solvent molecules, can play a key role in determining the observable bulk properties of the molecule. This is especially true in cases where strong local hydrogen bonding exists between the molecule and the solvent. One method that can probe the microsolvated states of charged molecules is differential mobility spectrometry (DMS), which rapidly interrogates an ion's transitions between a solvated and desolvated state in the gas phase (i.e., few solvent molecules present). However, can the results of DMS analyses of a class of molecules reveal information about the bulk physicochemical properties of those species? Our findings presented here show that DMS behaviors correlate strongly with the measured solution phase pKa and pKb values, and cell permeabilities of a set of structurally related drug molecules, even yielding high-resolution discrimination between isomeric forms of these drugs. This is due to DMS's ability to separate species based upon only subtle (yet predictable) changes in structure: the same subtle changes that can influence isomers' different bulk properties. Using 2-methylquinolin-8-ol as the core structure, we demonstrate how DMS shows promise for rapidly and sensitively probing the physicochemical properties of molecules, with particular attention paid to drug candidates at the early stage of drug development. This study serves as a foundation upon which future drug molecules of different structural classes could be examined.

  10. Biofunctional constituent isolated from Citrullus colocynthis fruits and structure-activity relationships of its analogues show acaricidal and insecticidal efficacy. (United States)

    Jeon, Ju-Hyun; Lee, Hoi-Seon


    The acaricidal and insecticidal potential of the active constituent isolated from Citrullus colocynthis fruits and its structurally related analogues was evaluated by performing leaf disk, contact toxicity, and fumigant toxicity bioassays against Tetranychus urticae, Sitophilus oryzae, and Sitophilus zeamais adults. The active constituent of C. colocynthis fruits was isolated by chromatographic techniques and was identified as 4-methylquinoline on the basis of spectroscopic analyses. To investigate the structure-activity relationships, 4-methylquinoline and its structural analogues were tested against mites and two insect pests. On the basis of the LC50 values, 7,8-benzoquinoline was the most effective against T. urticae. Quinoline, 8-hydroxyquinoline, 2-methylquinoline, 4-methylquinoline, 6-methylquinoline, 8-methylquinoline, and 7,8-benzoquinoline showed high insecticidal activities against S. oryzae and S. zeamais regardless of the application method. These results indicate that introduction of a functional group into the quinoline skeleton and changing the position of the group have an important influence on the acaricidal and insecticidal activities. Furthermore, 4-methylquinoline isolated from C. colocynthis fruits, along with its structural analogues, could be effective natural pesticides for managing spider mites and stored grain weevils.

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

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    Niewerth Heiko


    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

  12. Design, synthesis, physicochemical studies, solvation, and DNA damage of quinoline-appended chalcone derivative: comprehensive spectroscopic approach toward drug discovery. (United States)

    Kumar, Himank; Chattopadhyay, Anjan; Prasath, R; Devaraji, Vinod; Joshi, Ritika; Bhavana, P; Saini, Praveen; Ghosh, Sujit Kumar


    The present study epitomizes the design, synthesis, photophysics, solvation, and interaction with calf-thymus DNA of a potential antitumor, anticancer quinoline-appended chalcone derivative, (E)-3-(anthracen-10-yl)-1-(6,8-dibromo-2-methylquinolin-3-yl)prop-2-en-1-one (ADMQ) using steady state absorption and fluorescence spectroscopy, molecular modeling, molecular docking, Fourier-transform infrared spectroscopy (FTIR), molecular dynamics (MD) simulation, and gel electrophoresis studies. ADMQ shows an unusual photophysical behavior in a variety of solvents of different polarity. The dual emission has been observed along with the formation of twisted intramolecular charge transfer (TICT) excited state. The radiationless deactivation of the TICT state is found to be promoted strongly by hydrogen bonding. Quantum mechanical (DFT, TDDFT, and ZINDO-CI) calculations show that the ADMQ is sort of molecular rotor which undergoes intramolecular twist followed by a complete charge transfer in the optimized excited state. FTIR studies reveals that ADMQ undergoes important structural change from its native structure to a β-hydroxy keto form in water at physiological pH. The concentration-dependent DNA cleavage has been identified in agarose gel DNA electrophoresis experiment and has been further supported by MD simulation. ADMQ forms hydrogen bond with the deoxyribose sugar attached with the nucleobase adenine DA-17 (chain A) and result in significant structural changes which potentially cleave DNA double helix. The compound does not exhibit any deleterious effect or toxicity to the E. coli strain in cytotoxicity studies. The consolidated spectroscopic research described herein can provide enormous information to open up new avenues for designing and synthesizing chalcone derivatives with low systematic toxicity for medicinal chemistry research.