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Sample records for 42-hydroxy phenyl quinoxaline

  1. 3-{2-[(3-Phenyl­quinoxalin-2-yl)­oxy]ethyl}-1,3-oxazolidin-2-one

    PubMed Central

    Daouda, Ballo; Brelot, Lydia; Doumbia, Mouhamadou Lamine; Essassi, El Mokhtar; Ng, Seik Weng

    2011-01-01

    The asymmetric unit of the title compound, C19H17N3O3, consists of two independent mol­ecules that are disposed about a pseudo-centre of inversion. The plane of the phenyl substituent is twisted by 38.1 (1)° [43.6 (1)° in the second mol­ecule] out of the plane of the quinoxaline ring system. The five-membered ring of the substituent at the 2-position adopts an envelope conformation; the 5-CH2 atom representing the flap lies out of the plane defined by the other four atoms [deviation 0.264 (7) Å in the first mol­ecule and 0.291 (6) Å in the second]. The dihedral angle between the five-membered ring and the 4-phenyl ring is 84.9 (1)° while that between the five-membered ring and the 5-phenyl ring is 65.6 (1)°. PMID:21754531

  2. (Phen­yl)(3-phenyl­sulfonyl-1,2-dihydro­pyrrolo­[1,2-a]quinoxalin-1-yl)methanone

    PubMed Central

    Dürüst, Yaşar; Sağırlı, Akın; Fronczek, Frank R.

    2011-01-01

    In the title mol­ecule, C24H18N2O3S, the 13-atom ring system comprising the quinoxaline and fused five-membered ring exhibits an r.m.s. deviation from coplanarity of 0.039 Å, with a maximum deviation of 0.0710 (10) Å for the PhCO-bearing C atom of the five-membered ring. The 10-membered C8N2 quinoxaline ring system has an r.m.s. deviation from coplanarity of 0.022 Å, with a maximum deviation of 0.0403 (9) Å for the C atom involved in the C=C bond in the five-membered ring. The three atoms of the five-membered ring fused to the quinoxaline ring system show deviations of up to 0.118 (2) Å for the PhCO-bearing C atom. C—N bond distances in the quinoxaline ring system of the title mol­ecule deviate from those in unsubstituted quinoxaline. In particular, the two C—N distances to the N atom involved in the five-membered ring are essentially equal, with values of 1.3786 (17) and 1.3773 (16) Å, unlike the difference of nearly 0.06 Å in quinoxaline. PMID:22219900

  3. Two Dimensional Aggregation Behaviors of Quinoxaline Dendrimers.

    PubMed

    Choi, Soyoung; Lee, Hoik; Kim, Hwan Kyu; Lee, Sang Uck; Sohn, Daewon

    2015-02-01

    This study focuses on the molecular behavior of two dendrimers containing a hydrophilic core group (carboxyl group) and hydrophobic branches (quinoxaline and methoxyphenyl groups), 2,3-bis(4-(2,3- bis(4-methoxyphenyl)quinoxalin-6-yloxy)phenyl)quinoxaline-6-carb-oxylic acid (G2) and 2,3-bis(4-(2,3-bis(4-(2,3-bis(4-methoxyphenyl)quinoxalin-6-yloxy)phe-nyl)quinoxalin-6-y-oxy)phenyl) quin oxaline-6-carboxylic acid (G3) at the air-water interface. To understand the mechanism of the self-assembly of these molecules, we measured the surface pressure-area (III-A) isotherm and investigated the surface morphology of Langmuir-Blodgett films transferred onto hydrophilic silicon wafers using atomic force microscopy (AFM). Upon compression, G2 molecules stand up and steadily make close-packed monolayer whereas G3 molecules form circular domains and gradually make aggregates of domains. These results were confirmed by the X-ray Reflectivity (XRR) profiles of G2 and G3 monolayers transferred onto silicon substrates. PMID:26353682

  4. Visible-light-induced, copper(I)-catalysed C-N coupling between o-phenylenediamine and terminal alkynes: one-pot synthesis of 3-phenyl-2-hydroxy-quinoxalines.

    PubMed

    Sagadevan, Arunachalam; Ragupathi, Ayyakkannu; Hwang, Kuo Chu

    2013-12-01

    Visible-light-initiated aerobic direct C-N coupling between o-phenylenediamines and terminal acetylenes was performed using simple copper(I) chloride as a catalyst for the synthesis of quinoxaline derivatives. The current method works well for a wide range of electron rich as well as electron poor group-substituted o-phenylenediamines and phenylacetylenes. The key component in the reaction is the direct photo-excitation of in situ generated copper arylacetylide (λ(abs) = 420-480 nm). Moreover, as compared to the literature reports (thermal process), the current photochemical method is simple, mild, high yielding, and more viable towards the construction of biologically important quinoxaline derivatives from easily accessible raw materials, without the need of ligands and strong oxidants. PMID:24057350

  5. Quinoxalines Potential to Target Pathologies.

    PubMed

    Tristán-Manzano, María; Guirado, Antonio; Martínez-Esparza, María; Gálvez, Jesús; García-Peñarrubia, Pilar; Ruiz-Alcaraz, Antonio J

    2015-01-01

    The study of quinoxalines has increased immeasurably during the last two decades, due firstly to their relatively simple chemical synthesis, which has generated a vast variety of compounds with diverse structural modifications, and secondly, to the wide therapeutic potential and biological activities exhibited by this family of compounds. Quinoxalines constitute a rising biomedical class of low-molecular weight heterocyclic compounds with potential functions as antitumour, anti-inflammatory, antibacterial, antiviral, antifungal, antiparasitic and antidiabetic agents, as well as being of interest for the potential treatment of glaucoma, insomnia, cardiovascular and neurological diseases, among others. However, a deeper knowledge of the molecular targets of quinoxalines that fulfil a key role in certain pathologies is required for the development of new and more specific drugs through a rational design strategy to avoid undesirable side effects. In the present review, we summarize the most important molecular targets of the quinoxaline derivatives discovered to date, thus providing a first reference index for researchers to identify the potential targets of their quinoxalines derived collections, which could facilitate the development of new quinoxaline- based therapies. PMID:26264925

  6. First Evidence of Palytoxin and 42-Hydroxy-palytoxin in the Marine Cyanobacterium Trichodesmium

    PubMed Central

    Kerbrat, Anne Sophie; Amzil, Zouher; Pawlowiez, Ralph; Golubic, Stjepko; Sibat, Manoella; Darius, Helene Taiana; Chinain, Mireille; Laurent, Dominique

    2011-01-01

    Marine pelagic diazotrophic cyanobacteria of the genus Trichodesmium (Oscillatoriales) are widespread throughout the tropics and subtropics, and are particularly common in the waters of New Caledonia. Blooms of Trichodesmium are suspected to be a potential source of toxins in the ciguatera food chain and were previously reported to contain several types of paralyzing toxins. The toxicity of water-soluble extracts of Trichodesmium spp. were analyzed by mouse bioassay and Neuroblastoma assay and their toxic compounds characterized using liquid chromatography coupled with tandem mass spectrometry techniques. Here, we report the first identification of palytoxin and one of its derivatives, 42-hydroxy-palytoxin, in field samples of Trichodesmium collected in the New Caledonian lagoon. The possible role played by Trichodesmium blooms in the development of clupeotoxism, this human intoxication following the ingestion of plankton-eating fish and classically associated with Ostreopsis blooms, is also discussed. PMID:21731549

  7. Acute oral toxicity in mice of a new palytoxin analog: 42-hydroxy-palytoxin.

    PubMed

    Tubaro, A; Del Favero, G; Beltramo, D; Ardizzone, M; Forino, M; De Bortoli, M; Pelin, M; Poli, M; Bignami, G; Ciminiello, P; Sosa, S

    2011-04-01

    The acute oral toxicity of a new palytoxin congener, 42-hydroxy-palytoxin (42-OH-PLTX), was investigated in female CD-1 mice. The toxin (300-1697 μg/kg), administered by gavage, induced scratching, jumping, respiratory distress, cyanosis, paralysis and death of mice, with an LD₅₀ of 651 μg/kg (95% confidence limits: 384-1018 μg/kg) within 24 h. Hematoclinical analyses showed increased plasma levels of lactate dehydrogenase and aspartate-aminotransferase at doses of 600 μg/kg and above, as well as of alanine-aminotransferase, creatine phosphokinase and potassium ions at ≥ 848 μg/kg. Histology revealed inflammatory lesions in the non-glandular area of the stomach of mice that survived up to 24 h after gavage (424-1200 μg/kg). Although no histological alterations were seen in skeletal and cardiac muscles, changes in some plasma biomarkers (creatine phosphokinase, lactate dehydrogenase) suggested involvement of these tissues in 42-OH-PLTX oral toxicity, in agreement with epidemiological data on seafood poisonings ascribed to palytoxins. Complete recovery of the tissue and hematological changes was observed two weeks post-exposure. Furthermore, 42-OH-PLTX induced in vitro delayed erythrocyte hemolysis at concentrations similar to those of PLTX (EC₅₀ = 7.6 and 13.2 x 10⁻¹² M, respectively). This hemolysis could be completely neutralized by a monoclonal anti-PLTX antibody. The in vivo data, together with the in vitro data recorded for 42-OH-PLTX, seem to indicate Na+/K+-ATPase as one of the key cellular targets of this toxin. PMID:21333670

  8. 1-Benzyl-3-methyl­quinoxalin-2(1H)-one

    PubMed Central

    Ramli, Youssef; Moussaif, Ahmed; Zouihri, Hafid; Lazar, Saïd; Essassi, E. M.

    2010-01-01

    The asymmetric unit of the title compound, C16H14N2O, contains three independent mol­ecules. The dihedral angles between the quinoxaline and phenyl planes in the three mol­ecules are 82.58 (8), 85.66 (9) and 85.36 (9)°. The crystal packing is stabilized by C—H⋯O and C—H⋯N hydrogen bonds. PMID:21588252

  9. Unexpected imidazoquinoxalinone annulation products in the photoinitiated reaction of substituted-3-methyl-quinoxalin-2-ones with N-phenylglycine.

    PubMed

    De la Fuente, Julio R; Cañete, Álvaro; Jullian, Carolina; Saitz, Claudio; Aliaga, Christian

    2013-01-01

    Photoinduced electron transfer between N-phenylglycine (NPG) and electronically excited triplets of 7-substituted-3-methyl-quinoxalin-2-ones in acetonitrile generate the respective ion radical pair, where by decarboxylation the phenyl-amino-alkyl radical, PhNHCH2•, is generated. This radical reacts with the 3-methyl-quinoxalin-2-ones ground states, leading to the product 2. Other, unexpected, 7-substituted-1,2,3,3a-tetrahydro-3a-methyl-2-phenylimidazo[1,5-a]quinoxalin-4(5H)-ones, annulation products, 3a-f, were generated; likely by the addition of two PhNHCH2• radicals, to positions 3 and 4 of the quinoxalin-2-ones. The reaction mechanism includes a photoinduced one electron transfer initiation step, propagation steps involving radical intermediates and NPG with radical chain termination steps that lead to the respective products 2a-f and 3a-f and NPG by-products. The proposed mechanism accounts for the strong dependency found for the initial photoconsumption quantum yields on the electron-withdrawing power of the substituent. Therefore, photolysis of common reactants widely used such as NPG and substituted quinoxalin-2-ones may provide a simple synthetic way to the unusual, unreported tetrahydro-imidazoquinoxalinones 3a-f. PMID:24033113

  10. Synthesis, in vitro anticancer screening and radiosensitizing evaluation of some new 4-[3-(substituted)thioureido]-N-(quinoxalin-2-yl)-benzenesulfonamide derivatives.

    PubMed

    Ghorab, Mostafa M; Ragab, Fatma A; Heiba, Helmy I; El-Gazzar, Marwa G; El-Gazzar, Mostafa G

    2011-12-01

    Sulfonamides and quinoxaline derivatives possess many types of biological activities and have been recently reported to show substantial antitumor activity. This paper reports the synthesis of novel thioureido sulfaquinoxaline derivatives. All the newly synthesized compounds were evaluated for their in vitro anticancer activity against a human liver cell line (HEPG2) and showed higher activity than the reference drug doxorubicin. 4-(3-(4-Ethylbenzoate) thioureido)-N-(quinoxalin-2-yl)benzenesulfonamide (9) (IC₅₀ = 15.6 μmol L⁻¹), N-(pyridin-2-yl)-4-(3-(4-(N-quinoxalin-2-yl-sulfamoyl)phenyl)thioureido)benzenesulfonamide (10) (IC₅₀ = 26.8 μmol L⁻¹) and N-(quinoxalin-2-yl)-4-(3-(4-(N-thiazol-2-ylsulfamoyl)phenyl)thioureido)benzenesulfonamide (11) (IC₅₀ = 24.4 μmol L⁻¹) were the most potent compared to doxorubicin (IC₅₀ = 71.8 μmol L⁻¹). The most potent compounds 9, 10 and 11 were evaluated as radiosensitizing agents by subjecting the compounds to γ-irradiation (8 kGy). PMID:22202200

  11. Synthesis and Structure–Activity Relationship Studies of 4-((2-Hydroxy-3-methoxybenzyl)amino)benzenesulfonamide Derivatives as Potent and Selective Inhibitors of 12-Lipoxygenase

    PubMed Central

    Luci, Diane K.; Jameson, J. Brian; Yasgar, Adam; Diaz, Giovanni; Joshi, Netra; Kantz, Auric; Markham, Kate; Perry, Steve; Kuhn, Norine; Yeung, Jennifer; Kerns, Edward H.; Schultz, Lena; Holinstat, Michael; Nadler, Jerry L.; Taylor-Fishwick, David A.; Jadhav, Ajit; Simeonov, Anton; Holman, Theodore R.; Maloney, David J.

    2014-01-01

    Human lipoxygenases (LOXs) are a family of iron-containing enzymes which catalyze the oxidation of polyunsaturated fatty acids to provide the corresponding bioactive hydroxyeicosatetraenoic acid (HETE) metabolites. These eicosanoid signaling molecules are involved in a number of physiologic responses such as platelet aggregation, inflammation, and cell proliferation. Our group has taken a particular interest in platelet-type 12-(S)-LOX (12-LOX) because of its demonstrated role in skin diseases, diabetes, platelet hemostasis, thrombosis, and cancer. Herein, we report the identification and medicinal chemistry optimization of a 4-((2-hydroxy-3-methoxybenzyl)amino)benzenesulfonamide-based scaffold. Top compounds, exemplified by 35 and 36, display nM potency against 12-LOX, excellent selectivity over related lipoxygenases and cyclooxygenases, and possess favorable ADME properties. In addition, both compounds inhibit PAR-4 induced aggregation and calcium mobilization in human platelets and reduce 12-HETE in β-cells. PMID:24393039

  12. Chemistry and toxicology of quinoxaline, organotin, organofluorine, and formamidine acaricides.

    PubMed Central

    Knowles, C O

    1976-01-01

    Quinoxaline, organotin, organofluorine, and formamidine compounds are among the newer pesticide chemicals used for acarine control. Included in these four classes are some of the most selective synthetic organic toxicants currently in the acaricide/insecticide arsenal. Oxythioquinox, Plictran (tricyclohexylhydroxytin), Nissol [2-fluoro-N-methyl-N-(1-naphthyl)acetamide], and chlordimeform are examples of quinoxaline, organotin, organofluorine, and formamidine acaricides, respectively. The chemistry and toxicology of these and related compounds are discussed. PMID:789072

  13. BF3-promoted electrochemical properties of quinoxaline in propylene carbonate

    DOE PAGESBeta

    Carino, Emily V.; Diesendruck, Charles E.; Moore, Jeffrey S.; Curtiss, Larry A.; Assary, Rajeev S.; Brushett, Fikile R.

    2015-02-04

    Electrochemical and density functional studies demonstrate that coordination of electrolyte constituents to quinoxalines modulates their electrochemical properties. Quinoxalines are shown to be electrochemically inactive in most electrolytes in propylene carbonate, yet the predicted reduction potential is shown to match computational estimates in acetonitrile. We find that in the presence of LiBF4 and trace water, an adduct is formed between quinoxaline and the Lewis acid BF3, which then displays electrochemical activity at 1–1.5 V higher than prior observations of quinoxaline electrochemistry in non-aqueous media. Direct synthesis and testing of a bis-BF3 quinoxaline complex further validates the assignment of the electrochemically activemore » species, presenting up to a ~26-fold improvement in charging capacity, demonstrating the advantages of this adduct over unmodified quinoxaline in LiBF4-based electrolyte. The use of Lewis acids to effectively “turn on” the electrochemical activity of organic molecules may lead to the development of new active material classes for energy storage applications.« less

  14. Evaluation of the mutagenicity of simple substituted quinoxalines in Salmonella typhimurium.

    PubMed

    Conti, Luigi; Crebelli, Riccardo

    2016-01-01

    Limited information is available on the genotoxicity of simple quinoxalines, distinct from the food related carcinogenic derivatives bearing an aromatic amino group. Isolated positive results, with no apparent structure-activity relationships, were reported in earlier studies on alkyl substituted quinoxalines, raising a safety concern in some regulatory authorities in view of the potential human exposure related to their use as food flavors. In order to elucidate the genotoxic hazard posed by simple quinoxalines, in this work a random set of mono- and bi-substituted methyl, chloro- and hydroxyl- quinoxalines have been tested in an OECD-compliant bacterial reversion test (TG 471). The results obtained do not highlight any genotoxic potential in the set of quinoxalines examined, and suggest that this may be a common trait for other simple substituted quinoxalines. Earlier published positive findings were not confirmed in this work, which call for a cautious approach in the use of literature data for regulatory purpose. PMID:26365056

  15. Quinoxaline polymers and copolymers derived from 1, 4-BIS(1'-napthalenyloxayl) benzene

    NASA Technical Reports Server (NTRS)

    Port, W. S.; Loszewski, R. C.

    1974-01-01

    A route for the synthesis of a new monomer, 1,4-bis(1'-naphthalenyl)-oxayl benzene, was devised, and six polymers and copolymers were prepared from this monomer, 1,4-bis(phenyloaxaly)benzene, 3,3'-diaminobenzidine and 3,3',4,4'-tetraaminobenzophenone. Thermogravimetric analysis showed that decomposition of these quinoxaline polymers and copolymers sets in at about 500 C but does not become significant in an inert atmosphere below 600 C. Oxidation becomes significant at about 550 C and the phenylquinoxaline homopolymer is somewhat more oxidation resistant than is the 1-naphthalenylquinoxaline homopolymer. Stress-relaxation measurements showed that, with two exceptions, the homopolymers and copolymers exhibited two second-order transition temperatures, one at about 204.4 C (400 F) and the other at about 315.6 C (600 F). No gross differences in the high temperature plasticity was observed between the naphthalenyl- and the phenyl-quinoaxaline homopolymers. Work was begun on a method for cross-linking polyquinoxalines. A new monomer, p-(methyloxaly)benzil, was synthesized, and model reaction studies showed that cross-linking of 2-methylquinoxaline polymers by a Michael condensation with dimaleimides will probably occur.

  16. Synthesis of quinoxaline azido and amino reverse ribofuranoside and their O-regioisomers.

    PubMed

    Ali, Ibrahim A I

    2014-01-01

    A series of quinoxaline azido reverse nucleosides 3a-c and their O-regioisomers 4a-c was prepared by reaction of quinoxaline 1a-c with 3-azido-3-deoxy-1,2-O-isopropylidene-5-p-toluenesulfonyl-D-ribofuranose (2) in the presence of sodium hydride. Structure modification of these interesting structures includes reduction and the subsequent acetylation reactions to give quinoxaline amino and acetyl amino reverse nucleosides and their O-regioisomers. PMID:24689845

  17. New Conjugates of Quinoxaline as Potent Antitubercular and Antibacterial Agents

    PubMed Central

    Kuppusamy, Rajendran; Killi, Sunil Kumar; Reddy, Y. Padmanabha

    2016-01-01

    Considering quinoxaline as a privileged structure for the design of potent intercalating agents, some new sugar conjugates of quinoxaline were synthesized and characterized by IR, 1HNMR, 13C NMR, and mass spectral data. In vitro testing for antitubercular and antimicrobial activities was performed against Mycobacterium tuberculosis H37Rv and some pathogenic bacteria. Results revealed that conjugate containing ribose moiety demonstrated the most promising activity against Mycobacteria and bacteria with minimum inhibitory concentrations (MIC) of 0.65 and 2.07 μM, respectively. Other conjugates from xylose, glucose, and mannose were moderately active whilst disaccharides conjugates were found to be less active. In silico docking analysis of prototype compound revealed that ATP site of DNA gyrase B subunit could be a possible site for inhibitory action of these synthesized compounds. PMID:27051530

  18. 2,3-Dimethyl-6-nitro­quinoxaline

    PubMed Central

    Ghalib, Raza Murad; Hashim, Rokiah; Mehdi, Sayed Hasan; Goh, Jia Hao; Fun, Hoong-Kun

    2010-01-01

    The asymmetric unit of the title quinoxaline compound, C10H9N3O2, contains two crystallographically independent mol­ecules (A and B). The quinoxaline ring systems are essentially planar, with maximum deviations of 0.006 (1) and 0.017 (1) Å, respectively, for mol­ecules A and B. In mol­ecule A, the dihedral angle formed between the quinoxaline ring system and nitro group is 10.94 (3)° [6.31 (13)° for mol­ecule B]. In the crystal, mol­ecules are linked into chains propagating along [001]: one forms zigzag chains linked by C—H⋯O hydrogen bonds, whilst the other forms ladder-like chains by way of C—H⋯N and C—H⋯O hydrogen bonds. The packing is further consolidated by weak π–π inter­actions [range of centroid–centroid distances = 3.5895 (7)–3.6324 (7) Å]. PMID:21588035

  19. Asymmetric hydrogenation of 2- and 2,3-substituted quinoxalines with chiral cationic ruthenium diamine catalysts.

    PubMed

    Qin, Jie; Chen, Fei; Ding, Ziyuan; He, Yan-Mei; Xu, Lijin; Fan, Qing-Hua

    2011-12-16

    The enantioselective hydrogenation of 2-alkyl- and 2-aryl-subsituted quinoxalines and 2,3-disubstituted quinoxalines was developed by using the cationic Ru(η(6)-cymene)(monosulfonylated diamine)(BArF) system in high yields with up to 99% ee. The counteranion was found to be critically important for the high enantioselectivity and/or diastereoselectivity. PMID:22098608

  20. Radical Chemistry and Cytotoxicity of Bioreductive 3-Substituted Quinoxaline Di-N-Oxides.

    PubMed

    Anderson, Robert F; Yadav, Pooja; Shinde, Sujata S; Hong, Cho R; Pullen, Susan M; Reynisson, Jóhannes; Wilson, William R; Hay, Michael P

    2016-08-15

    The radical chemistry and cytotoxicity of a series of quinoxaline di-N-oxide (QDO) compounds has been investigated to explore the mechanism of action of this class of bioreductive drugs. A series of water-soluble 3-trifluoromethyl (4-10), 3-phenyl (11-19), and 3-methyl (20-21) substituted QDO compounds were designed to span a range of electron affinities consistent with bioreduction. The stoichiometry of loss of QDOs by steady-state radiolysis of anaerobic aqueous formate buffer indicated that one-electron reduction of QDOs generates radicals able to initiate chain reactions by oxidation of formate. The 3-trifluoromethyl analogues exhibited long chain reactions consistent with the release of the HO(•), as identified in EPR spin trapping experiments. Several carbon-centered radical intermediates, produced by anaerobic incubation of the QDO compounds with N-terminal truncated cytochrome P450 reductase (POR), were characterized using N-tert-butyl-α-phenylnitrone (PBN) and 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide (DEPMPO) spin traps and were observed by EPR. Experimental data were well simulated for the production of strongly oxidizing radicals, capable of H atom abstraction from methyl groups. The kinetics of formation and decay of the radicals produced following one-electron reduction of the parent compounds, both in oxic and anoxic solutions, were determined using pulse radiolysis. Back oxidation of the initially formed radical anions by molecular oxygen did not compete effectively with the breakdown of the radical anions to form oxidizing radicals. The QDO compounds displayed low hypoxic selectivity when tested against oxic and hypoxic cancer cell lines in vitro. The results from this study form a kinetic description and explanation of the low hypoxia-selective cytotoxicity of QDOs against cancer cells compared to the related benzotriazine 1,4-dioxide (BTO) class of compounds. PMID:27380897

  1. 3-Methyl-1-(prop-2-en-1-yl)quinoxalin-2(1H)-one

    PubMed Central

    Ramli, Youssef; Slimani, Rachid; Zouihri, Hafid; Lazar, Saïd; Essassi, E. M.

    2010-01-01

    In the mol­ecule of the title compound, C12H12N2O, the quinoxaline ring is planar with an r.m.s. deviation of 0.007 (15) Å. The dihedral angle between the quinoxaline and propenyl planes is 82.1 (2)°. The crystal packing is stabilized by offset π–π stacking between the quinoxaline rings [centroid–centroid distance = 3.8832 (9) Å]. PMID:21587981

  2. Phenanthro[4,5-fgh]quinoxaline-Fused Subphthalocyanines: Synthesis, Structure, and Spectroscopic Characterization.

    PubMed

    Pan, Houhe; Liu, Wenbo; Wang, Chiming; Wang, Kang; Jiang, Jianzhuang

    2016-07-01

    A series of four phenanthro[4,5-fgh]quinoxaline-fused subphthalocyanine derivatives 0-3 containing zero, one, two, and three phenanthro[4,5-fgh]quinoxaline moieties, respectively, were isolated from the mixed cyclotrimerization reaction of 2,9-di-tert-butylphenanthro[4,5-fgh]quinoxaline-5,6-dicarbonitrile with 4,5-bis(2,6-diisopropylphenoxy)phthalonitrile and characterized by a series of spectroscopic methods including MALDI-TOF mass, (1) H NMR, electronic absorption, magnetic circular dichroism (MCD), and fluorescence spectroscopy. The molecular structures for the compounds 0 and 2 were clearly revealed on the basis of single-crystal X-ray diffraction analysis. Their electrochemical properties were also studied by cyclic voltammetry. In particular, theoretical calculations in combination with the electronic absorption and electrochemical analyses revealed the significant influence of the fused-phenanthro[4,5-fgh]quinoxaline units on the electronic structures. PMID:27123546

  3. Photochemical reactions of biologically important quinoxaline n-oxides

    SciTech Connect

    Dvoryantseva, G.G.; Tetenchuk, K.P.; Pol'shakov, V.I.; Elina, A.S.

    1987-02-01

    The authors study the photochemical reactions of quinoxidine, dioxidine, and a number of related derivatives of quinoxaline 1,4-di-N-oxides containing methyl, halomethyl, and carboxamide groups in the pyrazine ring. Thin-layer chromatography, UV spectrophotometry, and NMR/sup 1/H and /sup 13/C spectroscopy were used as the main methods for monitoring the photolysis process and establishing the structure of the products formed. The investigation established that two types of photochemical reactions are observed in the series of compounds discussed: photoisomerization with migration of a substitutent to the nitrogen atom of the heterocycle, and photorearrangement with elimination of a substituent and the formation of the corresponding lactams.

  4. One-Pot Regiospecific Synthesis of Quinoxalines via a CH2-Extrusion Reaction.

    PubMed

    Shen, Jinhai; Wang, Xiangdong; Lin, Xing; Yang, Zhenhui; Cheng, Guolin; Cui, Xiuling

    2016-03-18

    A convenient "one-pot" regiospecific synthesis of substituted quinoxalines from o-phenylenediamines and ynones under metal-free conditions has been developed. An intermolecular Michael addition reaction, a dehydration condensation, and a base-promoted C-α-CH2-extrusion were involved in this procedure, which features high regioselectivity, efficiency, and environmental friendliness. Various quinoxalines were provided in up to 95% yield for 33 examples. PMID:26925522

  5. Synthesis, ligand-receptor modeling studies and pharmacological evaluation of novel 4-modified-2-aryl-1,2,4-triazolo[4,3-a]quinoxalin-1-one derivatives as potent and selective human A3 adenosine receptor antagonists.

    PubMed

    Colotta, Vittoria; Catarzi, Daniela; Varano, Flavia; Lenzi, Ombretta; Filacchioni, Guido; Martini, Claudia; Trincavelli, Letizia; Ciampi, Osele; Traini, Chiara; Pugliese, Anna Maria; Pedata, Felicita; Morizzo, Erika; Moro, Stefano

    2008-06-01

    The study of some 4-substituted-2-aryl-1,2,4-triazolo[4,3-a]quinoxalin-1-one derivatives, designed as hA(3) adenosine receptor antagonists, is reported. The new compounds bear on the four-position different acylamino, sulfonylamino, benzylureido and benzyloxy moieties, which have also been combined with a para-methoxy group on the 2-phenyl ring or with a nitro residue at the six-position. Many derivatives show high hA(3) adenosine receptor affinities and selectivities both versus hA(1) and hA(2A) receptors. The observed structure-affinity relationships of this class of antagonists have been exhaustively rationalized using the recently published ligand-based homology modeling (LBHM) approach. The selected 4-bismethanesulfonylamino-2-phenyl-1,2,4-triazolo[4,3-a]quinoxalin-1-one (13), which shows high hA(3) affinity (K(i)=5.5nM) and selectivity versus hA(1), hA(2A) (both selectivity ratios>1800) and hA(2B) (cAMP assay, IC(50)>10,000nM) receptors, was tested in an in vitro rat model of cerebral ischemia, proving to be effective in preventing the failure of synaptic activity, induced by oxygen and glucose deprivation in the hippocampus, and in delaying the occurrence of anoxic depolarization. PMID:18468446

  6. BF3-promoted electrochemical properties of quinoxaline in propylene carbonate

    SciTech Connect

    Carino, Emily V.; Diesendruck, Charles E.; Moore, Jeffrey S.; Curtiss, Larry A.; Assary, Rajeev S.; Brushett, Fikile R.

    2015-02-04

    Electrochemical and density functional studies demonstrate that coordination of electrolyte constituents to quinoxalines modulates their electrochemical properties. Quinoxalines are shown to be electrochemically inactive in most electrolytes in propylene carbonate, yet the predicted reduction potential is shown to match computational estimates in acetonitrile. We find that in the presence of LiBF4 and trace water, an adduct is formed between quinoxaline and the Lewis acid BF3, which then displays electrochemical activity at 1–1.5 V higher than prior observations of quinoxaline electrochemistry in non-aqueous media. Direct synthesis and testing of a bis-BF3 quinoxaline complex further validates the assignment of the electrochemically active species, presenting up to a ~26-fold improvement in charging capacity, demonstrating the advantages of this adduct over unmodified quinoxaline in LiBF4-based electrolyte. The use of Lewis acids to effectively “turn on” the electrochemical activity of organic molecules may lead to the development of new active material classes for energy storage applications.

  7. Photo-degradation in air of the active layer components in a thiophene-quinoxaline copolymer:fullerene solar cell.

    PubMed

    Hansson, Rickard; Lindqvist, Camilla; Ericsson, Leif K E; Opitz, Andreas; Wang, Ergang; Moons, Ellen

    2016-04-28

    We have studied the photo-degradation in air of a blend of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1), and how the photo-degradation affects the solar cell performance. Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, changes to the electronic structure of TQ1 and PCBM caused by illumination in ambient air are investigated and compared between the pristine materials and the blend. The NEXAFS spectra show that the unoccupied molecular orbitals of TQ1 are not significantly changed by the exposure of pristine TQ1 to light in air, whereas those of PCBM are severely affected as a result of photo-induced degradation of PCBM. Furthermore, the photo-degradation of PCBM is accelerated by blending it with TQ1. While the NEXAFS spectrum of TQ1 remains unchanged upon illumination in air, its valence band spectrum shows that the occupied molecular orbitals are weakly affected. Yet, UV-Vis absorption spectra demonstrate photo-bleaching of TQ1, which is attenuated in the presence of PCBM in blend films. Illumination of the active layer of TQ1:PCBM solar cells prior to cathode deposition causes severe losses in electrical performance. PMID:27051887

  8. Vertical and lateral morphology effects on solar cell performance for a thiophene–quinoxaline copolymer:PC 70BM blend

    DOE PAGESBeta

    Hansson, Rickard; Ericsson, Leif K. E.; Holmes, Natalie P.; Rysz, Jakub; Opitz, Andreas; Campoy-Quiles, Mariano; Wang, Ergang; Barr, Matthew G.; Kilcoyne, A. L. David; Zhou, Xiaojing; et al

    2015-02-13

    The distribution of electron donor and acceptor in the active layer is known to strongly influence the electrical performance of polymer solar cells for most of the high performance polymer:fullerene systems. The formulation of the solution from which the active layer is spincoated plays an important role in the quest for morphology control. We have studied how the choice of solvent and the use of small amounts of a low vapour pressure additive in the coating solution influence the film morphology and the solar cell performance for blends of poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1) and [6,6]-phenyl C71-butyric acid methyl ester (PC70BM). We havemore » investigated the lateral morphology using atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM), the vertical morphology using dynamic secondary ion mass spectrometry (d-SIMS) and variable-angle spectroscopic ellipsometry (VASE), and the surface composition using near-edge X-ray absorption fine structure (NEXAFS). The lateral phase-separated domains observed in films spincoated from single solvents, increase in size with increasing solvent vapour pressure and decreasing PC70BM solubility, but are not observed when 1-chloronaphthalene (CN) is added. A strongly TQ1-enriched surface layer is formed in all TQ1:PC70BM blend films and rationalized by surface energy differences. The photocurrent and power conversion efficiency strongly increased upon the addition of CN, while the leakage current decreased by one to two orders of magnitude. The higher photocurrent correlates with the finer lateral structure and stronger TQ1-enrichment at the interface with the electron-collecting electrode. This indicates that the charge transport and collection are not hindered by this polymer-enriched surface layer. Neither the open-circuit voltage nor the series resistance of the devices are sensitive to the differences in morphology.« less

  9. Iodinated (Perfluoro)alkyl Quinoxalines by Atom Transfer Radical Addition Using ortho-Diisocyanoarenes as Radical Acceptors.

    PubMed

    Leifert, Dirk; Studer, Armido

    2016-09-12

    A simple method for the preparation of functionalized quinoxalines is reported. Starting from readily accessible ortho-diisocyanoarenes and (perfluoro)alkyl iodides, the quinoxaline core is constructed during (perfluoro)alkylation by atom transfer radical addition (ATRA), resulting in 2-iodo-3-(perfluoro)alkylquinoxalines. The radical cascades are readily initiated either with visible light or by using α,α'-azobisisobutyronitrile (AIBN). The heteroarene products are obtained in high yields (up to 94 %), and the method can be readily scaled up. Useful follow-up chemistry documents the value of the novel radical quinoxaline synthesis. PMID:27510610

  10. 4-amido-2-aryl-1,2,4-triazolo[4,3-a]quinoxalin-1-ones as new potent and selective human A3 adenosine receptor antagonists. synthesis, pharmacological evaluation, and ligand-receptor modeling studies.

    PubMed

    Lenzi, Ombretta; Colotta, Vittoria; Catarzi, Daniela; Varano, Flavia; Filacchioni, Guido; Martini, Claudia; Trincavelli, Letizia; Ciampi, Osele; Varani, Katia; Marighetti, Federico; Morizzo, Erika; Moro, Stefano

    2006-06-29

    A structural investigation on some 4-amido-2-phenyl-1,2-dihydro-1,2,4-triazolo[4,3-a]quinoxalin-1-one derivatives, designed as human A3 adenosine receptor (hA3 AR) antagonists, is described. In the new derivatives, some acyl residues with different steric bulk were introduced on the 4-amino group, and their combination with the 4-methoxy group on the 2-phenyl moiety, and/or the 6-nitro/6-amino substituent on the fused benzo ring, was also evaluated. Most of the new derivatives were potent and selective hA3 AR antagonists. SAR analysis showed that hindering and lipophilic acyl moieties not only are well tolerated but even ameliorate the hA3 affinity. Interestingly, the 4-methoxy substituent on the appended 2-phenyl moiety, as well as the 6-amino group, always exerted a positive effect, shifting the affinity toward the hA3 receptor subtype. In contrast, the 6-nitro substituent exerted a variable effect. An intensive molecular modeling investigation was performed to rationalize the experimental SAR findings. PMID:16789747

  11. Design, synthesis and anti-HIV activity of novel quinoxaline derivatives.

    PubMed

    Patel, Saloni B; Patel, Bhumika D; Pannecouque, Christophe; Bhatt, Hardik G

    2016-07-19

    In order to design novel anti-HIV agents, pharmacophore modelling, virtual screening, 3D-QSAR and molecular docking studies were performed. Pharmacophore model was generated using 17 structurally diverse molecules using DISCOtech followed by refinement with GASP module of Sybyl X. The best model containing four features; two donor sites, one acceptor atom and one hydrophobic region; was used as a query for virtual screening in NCI database and 6 compounds with Qfit value ≥98 were retrieved. The quinoxaline ring which is the bio-isostere of pteridine ring, retrieved as a hit in virtual screening, was selected as a core moiety. 3D-QSAR was carried on thirty five 5-hydroxy-6-oxo-1,6-dihydropyrimidine-4-carboxamide derivatives. Contour map analysis of best CoMFA and CoMSIA model suggested incorporation of hydrophobic, bulky and electronegative groups to increase potency of the designed compounds. 50 quinoxaline derivatives with different substitutions were designed on basis of both ligand based drug design approaches and were mapped on the best pharmacophore model. From this, best 32 quinoxaline derivatives were docked onto the active site of integrase enzyme and in-silico ADMET properties were also predicted. From this data, synthesis of top 7 quinoxaline derivatives was carried out and were characterized using Mass, (1)H-NMR and (13)C-NMR spectroscopy. Purity of compounds were checked using HPLC. These derivatives were evaluated for anti-HIV activity on III-B strain of HIV-1 and cytotoxicity studies were performed on VERO cell line. Two quinoxaline derivatives (7d and 7e) showed good results, which can be further explored to develop novel anti-HIV agents. PMID:27105027

  12. Relationship between electronic properties and drug activity of seven quinoxaline compounds: A DFT study

    NASA Astrophysics Data System (ADS)

    Behzadi, Hadi; Roonasi, Payman; Assle taghipour, Khatoon; van der Spoel, David; Manzetti, Sergio

    2015-07-01

    The quantum chemical calculations at the DFT/B3LYP level of theory were carried out on seven quinoxaline compounds, which have been synthesized as anti-Mycobacterium tuberculosis agents. Three conformers were optimized for each compound and the lowest energy structure was found and used in further calculations. The electronic properties including EHOMO, ELUMO and related parameters as well as electron density around oxygen and nitrogen atoms were calculated for each compound. The relationship between the calculated electronic parameters and biological activity of the studied compounds were investigated. Six similar quinoxaline derivatives with possible more drug activity were suggested based on the calculated electronic descriptors. A mechanism was proposed and discussed based on the calculated electronic parameters and bond dissociation energies.

  13. New highlights of the syntheses of pyrrolo[1,2-a]quinoxalin-4-ones

    PubMed Central

    Georgescu, Emilian; Nicolescu, Alina; Georgescu, Florentina; Teodorescu, Florina; Marinescu, Daniela; Macsim, Ana-Maria

    2014-01-01

    Summary The one-pot three-component reactions of 1-substituted benzimidazoles with ethyl bromoacetate and electron-deficient alkynes, in 1,2-epoxybutane, gave a variety of pyrrolo[1,2-a]quinoxalin-4-ones and pyrrolo[1,2-a]benzimidazoles. The influence of experimental conditions on the course of reaction was investigated. A novel synthetic pathway starting from benzimidazoles unsubstituted at the five membered ring, alkyl bromoacetates and non-symmetrical electron-deficient alkynes in the molar ratio of 1:2:1, in 1,2-epoxybutane at reflux temperature, led directly to pyrrolo[1,2-a]quinoxalin-4-ones in fair yield by an one-pot three-component reaction. PMID:25383108

  14. Direct phosphonation of quinoxalin-2(1H)-ones under transition-metal-free conditions.

    PubMed

    Gao, Ming; Li, Yi; Xie, Lijuan; Chauvin, Remi; Cui, Xiuling

    2016-02-01

    A direct C-H bond phosphonation of quinoxalin-2(1H)-ones with H-phosphonates, H-phosphinates or H-phosphine oxides has been developed. A wide variety of heteroaryl phosphonates were obtained in up to 92% yield for 20 examples under transition-metal-free conditions. This protocol tolerates a broad scope of substrates and features practicality, high efficiency, environmental friendliness and atom economy. PMID:26779573

  15. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted phenyl azo substituted... Significant New Uses for Specific Chemical Substances § 721.3063 Substituted phenyl azo substituted phenyl... chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  16. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phenyl azo substituted... Significant New Uses for Specific Chemical Substances § 721.3063 Substituted phenyl azo substituted phenyl... as substituted phenyl azo substituted phenyl esters (PMNs P-95-655, P-95-782 and P-95-871)...

  17. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phenyl azo substituted... Significant New Uses for Specific Chemical Substances § 721.3063 Substituted phenyl azo substituted phenyl... chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  18. Advances in the synthesis of imidazo[1,5-a]- and imidazo[1,2-a]quinoxalines

    NASA Astrophysics Data System (ADS)

    Mamedov, V. A.; Kalinin, A. A.

    2014-09-01

    This review is intended to generalize and systematize available information on the synthesis of imidazo[1,5-a]- and imidazo[1,2-a]quinoxalines. Relevant studies published in the last 10-15 years, as well as earlier studies less familiar to the broad chemical community, are surveyed. Major methods of formation of the imidazoquinoxaline system from substituted quinoxalines and imidazoles according to the type of bond being formed are presented. Special focus is placed on the radically new methods that enable the synthesis of various derivatives of these heterocyclic systems from available and inexpensive reagents. The mechanisms of formation of these compounds are discussed. Information on the biological activity of imidazo[1,5-a]- and imidazo[1,2-a]quinoxalines and examples of pharmaceuticals based on them are reported. The bibliography includes 179 references.

  19. Crystal structure of 1,3-bis-(2,3-di-methyl-quinoxalin-6-yl)benzene.

    PubMed

    Diesendruck, Charles E; Rubin, Gabrielle; Bertke, Jeffery A; Gray, Danielle L; Moore, Jeffrey S

    2015-12-01

    The title compound, C26H22N4 (I), was synthesized by C-H iridium-catalyzed borylation followed by Suzuki coupling. The mol-ecular structure of (I) consists of a central benzene ring with 3-di-methyl-quinoxalin-6-yl groups at the 1 and 3 positions. These 2,3-di-methyl-quinoxalin-6-yl groups twist significantly out of the plane of the benzene ring. There are inter-molecular π-π inter-actions which result in a two-dimensional extended structure. The layers extend parallel to the ab plane and stack along the c axis. PMID:26870397

  20. 4-Chlorotetrazolo[1,5-a]quinoxaline inhibits activation of Syk kinase to suppress mast cells in vitro and mast cell-mediated passive cutaneous anaphylaxis in mice

    SciTech Connect

    Park, Kui Lea; Ko, Na Young; Lee, Jun Ho; Kim, Do Kyun; Kim, Hyuk Soon; Kim, A-Ram; Her, Erk; Kim, Bokyung; Kim, Hyung Sik; Moon, Eun-Yi; Kim, Young Mi; Kim, Hang-Rae; Choi, Wahn Soo

    2011-12-15

    4-Chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. We aimed to study the effects of 4-chlorotetrazolo[1,5-a]quinoxaline on activation of mast cells in vitro and in mice. 4-Chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited degranulation of mast cells in a dose-dependent manner, and also suppressed the expression and secretion of TNF-{alpha} and IL-4 in mast cells. Mechanistically, 4-chlorotetrazolo[1,5-a]quinoxaline inhibited activating phosphorylation of Syk and LAT, which are crucial for early Fc{epsilon}RI-mediated signaling events, as well as Akt and MAP kinases, which play essential roles in the production of various pro-inflammatory cytokines in mast cells. Notably, although 4-chlorotetrazolo[1,5-a]quinoxaline inhibited the activation of Fyn and Syk, minimal inhibition was observed in mast cells in the case of Lyn. Furthermore, consistent with its in vitro activity, 4-chlorotetrazolo[1,5-a]quinoxaline significantly suppressed mast cell-mediated passive cutaneous anaphylaxis in mice. In summary, the results from this study demonstrate that 4-chlorotetrazolo[1,5-a]quinoxaline shows an inhibitory effect on mast cells in vitro and in vivo, and that this is mediated by inhibiting the activation of Syk in mast cells. Therefore, 4-chlorotetrazolo[1,5-a]quinoxaline could be useful in the treatment of mast cell-mediated allergic diseases. -- Highlights: Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. Black-Right-Pointing-Pointer The effect of 4-chlorotetrazolo[1,5-a]quinoxaline on mast cells was investigated. Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited Syk activation. Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline could be useful for IgE-mediated allergy.

  1. Mode of Action of Quindoxin and Substituted Quinoxaline-di-N-Oxides on Escherichia coli

    PubMed Central

    Suter, W.; Rosselet, A.; Knüsel, F.

    1978-01-01

    The effect of quindoxin on the synthesis of deoxyribonucleic acid (DNA), ribonucleic acid, and protein in Escherichia coli KL 399 was examined under aerobic and anaerobic conditions. In the absence of oxygen the synthesis of DNA was completely inhibited by 10 ppm of quindoxin, whereas the syntheses of ribonucleic acid and protein were not affected. Quinoxalin-di-N-oxides (QdNO) induce degradation of DNA in both proliferating and non-proliferating cells. polA, recA, recB, recC, exrA, and uvrA mutants were more susceptible than the corresponding repair-proficient strains. All strains were more resistant in the presence of oxygen. Quindoxin was reduced to quinoxalin-N-oxide by intact E. coli cells or by a cell-free E. coli extract. Electron spin resonance measurements demonstrated the generation of free radicals during the reduction of quindoxin. Oxygen or deficiency of energy sources impaired the antibiotic activity and the reduction of QdNO. The QdNO reductase activity was demonstrated to be lower in QdNO-resistant mutants than in the susceptible parent strain. Based on these results it is concluded that an intermediate of reduction, probably a free radical, is responsible for the lethal effect of quindoxin. With three independent techniques no evidence has been found for binding of quindoxin to DNA. Images PMID:352264

  2. in Silico investigation of the structural requirements for the AMPA receptor antagonism by quinoxaline derivatives

    PubMed Central

    Azam, Faizul; Abugrain, Ismaiel Mohamed; Sanalla, Mohamed Hussin; Elnaas, Radwan Fatahalla; Rajab, Ibrahim Abdassalam Ibn

    2013-01-01

    Glutamate receptors have been implicated in various neurological disorders and their antagonism offers a suitable approach for the treatment of such disorders. The field of drug design and discovery aims to find best medicines to prevent, treat and cure diseases quickly and efficiently. In this regard, computational tools have helped medicinal chemists modify and optimize molecules to potent drug candidates with better pharmacokinetic profiles, and guiding biologists and pharmacologists to explore new disease genes as well as novel drug targets. In the present study, to understand the structural requirements for AMPA receptor antagonism, molecular docking study was performed on 41 structurally diverse antagonists based on quinoxaline nucleus. Lamarckian genetic algorithm methodology was employed for docking simulations using AutoDock 4.2 program. The results obtained signify that the molecular docking approach is reliable and produces a good correlation coefficient (r2 = 0.6) between experimental and docking predicted AMPA receptor antagonistic activity. The aromatic moiety of quinoxaline core has been proved to be vital for hydrophobic contacts exhibiting - interactions in docked conformations. However, polar moieties such as carboxylic group and 1,2,4-triazole moieties were noted to be sites for hydrophilic interactions in terms of hydrogen bonding with the receptor. These analyses can be exploited to design and develop novel AMPA receptor antagonists for the treatment of different neurological disorders. PMID:24250113

  3. Quinoxaline derivatives as corrosion inhibitors for mild steel in hydrochloric acid medium: Electrochemical and quantum chemical studies

    NASA Astrophysics Data System (ADS)

    Olasunkanmi, Lukman O.; Kabanda, Mwadham M.; Ebenso, Eno E.

    2016-02-01

    The corrosion inhibition potential of four quinoxaline derivatives namely, 1-[3-(4-methylphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Me-4-PQPB), 1-(3-(4-methoxyphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl)butan-1-one (Mt-4-PQPB), 1-[3-(3-methoxyphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Mt-3-PQPB) and 1-[3-(2H-1,3-benzodioxol-5-yl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Oxo-1,3-PQPB) was studied for mild steel corrosion in 1 M HCl solution using electrochemical, spectroscopic techniques and quantum chemical calculations. The results of both potentiodynamic polarization and electrochemical impedance spectroscopic studies revealed that the compounds are mixed-type inhibitors and the order of corrosion inhibition efficiency at 100 ppm is Me-4-PQPB>Mt-3-PQPB>Oxo-1,3-PQPB>Mt-4-PQPB. Fourier transform infrared (FTIR) and ultraviolet-visible (UV-vis) spectroscopic analyses confirmed the presence of chemical interactions between the inhibitors and mild steel surface. The adsorption of the inhibitor molecules on mild steel surface was found to be both physisorption and chemisorption but predominantly chemisorption. The experimental data obey Langmuir adsorption isotherm. Scanning electron microscopy studies revealed the formation of protective films of the inhibitors on mild steel surface. Quantum chemical parameters obtained from density functional theory (DFT) calculations support experimental results.

  4. Radiation-induced reduction of quinoxalin-2-one derivatives in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Skotnicki, Konrad; De la Fuente, Julio R.; Cañete, Alvaro; Bobrowski, Krzysztof

    2016-07-01

    Quinoxaline-2-one derivatives have been proposed as potential drugs in treatments of various diseases since some of them showed a variety of pharmacological properties. The kinetics and spectral characteristics of the transients formed in the reactions of hydrated electrons (eaq-) with quinoxalin-2-(1H)-one (Q) and its methyl derivative, 3-methyl quinoxalin-2-(1H)-one (3-MeQ) were studied by pulse radiolysis in aqueous solutions at pH ranging from 5 to 14. The transient absorption spectra recorded in the reactions of (eaq-) with Q and 3-MeQ at pH 7 consisted of a broad, almost flat band in the range 390-450 nm and were assigned to the respective protonated radical anions (QH•/3-MeQH•) at N4 atom in a pyrazin-2-one ring. On the other hand, the transient absorption spectra recorded in the reactions of (eaq-) with Q and 3-MeQ at pH 13 are characterized by a broad band with a much better pronounced maximum at λmax=390 nm and higher intensity (in comparison to that at pH 7) and were assigned to the respective radical anions (Q•-/3-MeQ•-). Both forms are involved in the prototropic equilibrium with the pKa located at pH≥13.5. The rate constants of the reactions of (eaq-) with Q and 3-MeQ were found to be at pH 7 (2.6±0.1)×1010 M-1 s-1 and (2.1±0.1)×1010 M-1 s-1 and at pH 13 (1.6±0.1)×1010 M-1 s-1 and (1.3±0.1)×1010 M-1 s-1, respectively. Semi-empirical quantum mechanical calculations reproduce fairly well the spectral features of the experimental absorption spectra and show that protonated radical anions at nitrogen atom (N4) in both molecules are the most stable hydrogenated radicals.

  5. Quinoxaline-based inhibitors of Ebola and Marburg VP40 egress.

    PubMed

    Loughran, H Marie; Han, Ziying; Wrobel, Jay E; Decker, Sarah E; Ruthel, Gordon; Freedman, Bruce D; Harty, Ronald N; Reitz, Allen B

    2016-08-01

    We prepared a series of quinoxalin-2-mercapto-acetyl-urea analogs and evaluated them for their ability to inhibit viral egress in our Marburg and Ebola VP40 VLP budding assays in HEK293T cells. We also evaluated selected compounds in our bimolecular complementation assay (BiMC) to detect and visualize a Marburg mVP40-Nedd4 interaction in live mammalian cells. Antiviral activity was assessed for selected compounds using a live recombinant vesicular stomatitis virus (VSV) (M40 virus) that expresses the EBOV VP40 PPxY L-domain. Finally selected compounds were evaluated in several ADME assays to have an early assessment of their drug properties. Our compounds had low nM potency in these assays (e.g., compounds 21, 24, 26, 39), and had good human liver microsome stability, as well as little or no inhibition of P450 3A4. PMID:27377328

  6. Fourier transform microwave and millimeter wave spectroscopy of quinazoline, quinoxaline, and phthalazine.

    PubMed

    McNaughton, Don; Godfrey, Peter D; Jahn, Michaela K; Dewald, David A; Grabow, Jens-Uwe

    2011-04-21

    The pure rotational spectra of the bicyclic aromatic nitrogen heterocycle molecules, quinazoline, quinoxaline, and phthalazine, have been recorded and assigned in the region 13-87 GHz. An analysis, guided by ab initio molecular orbital predictions, of frequency-scanned Stark modulated, jet-cooled millimeter wave absorption spectra (48-87 GHz) yielded a preliminary set of rotational and centrifugal distortion constants. Subsequent spectral analysis at higher resolution was carried out with Fourier transform microwave (FT-MW) spectroscopy (13-18 GHz) of a supersonic rotationally cold molecular beam. The high spectral resolution of the FT-MW instrument provided an improved set of rotational and centrifugal distortion constants together with nitrogen quadrupole coupling constants for all three species. Density functional theory calculations at the B3LYP∕6-311+G∗∗ level of theory closely predict rotational constants and are useful in predicting quadrupole coupling constants and dipole moments for such species. PMID:21513385

  7. In Vitro and In Vivo Activities of 2,3-Diarylsubstituted Quinoxaline Derivatives against Leishmania amazonensis.

    PubMed

    Kaplum, Vanessa; Cogo, Juliana; Sangi, Diego Pereira; Ueda-Nakamura, Tânia; Corrêa, Arlene Gonçalves; Nakamura, Celso Vataru

    2016-06-01

    Leishmaniasis is endemic in 98 countries and territories worldwide. The therapies available for leishmaniasis have serious side effects, thus prompting the search for new therapies. The present study investigated the antileishmanial activities of 2,3-diarylsubstituted quinoxaline derivatives against Leishmania amazonensis The antiproliferative activities of 6,7-dichloro-2,3-diphenylquinoxaline (LSPN329) and 2,3-di-(4-methoxyphenyl)-quinoxaline (LSPN331) against promastigotes and intracellular amastigotes were assessed, and the cytotoxicities of LSPN329 and LSPN331 were determined. Morphological and ultrastructural alterations were examined by electron microscopy, and biochemical alterations, reflected by the mitochondrial membrane potential (ΔΨm), mitochondrial superoxide anion (O2·(-)) concentration, the intracellular ATP concentration, cell volume, the level of phosphatidylserine exposure on the cell membrane, cell membrane integrity, and lipid inclusions, were evaluated. In vivo antileishmanial activity was evaluated in a murine cutaneous leishmaniasis model. Compounds LSPN329 and LSPN331 showed significant selectivity for promastigotes and intracellular amastigotes and low cytotoxicity. In promastigotes, ultrastructural alterations were observed, including an increase in lipid inclusions, concentric membranes, and intense mitochondrial swelling, which were associated with hyperpolarization of ΔΨm, an increase in the O2·(-) concentration, decreased intracellular ATP levels, and a decrease in cell volume. Phosphatidylserine exposure and DNA fragmentation were not observed. The cellular membrane remained intact after treatment. Thus, the multifactorial response that was responsible for the cellular collapse of promastigotes was based on intense mitochondrial alterations. BALB/c mice treated with LSPN329 or LSPN331 showed a significant decrease in lesion thickness in the infected footpad. Therefore, the antileishmanial activity and mitochondrial mechanism of

  8. Discovery of indeno[1,2-b]quinoxaline derivatives as potential anticancer agents.

    PubMed

    Tseng, Chih-Hua; Chen, You-Ren; Tzeng, Cherng-Chyi; Liu, Wangta; Chou, Chon-Kit; Chiu, Chien-Chih; Chen, Yeh-Long

    2016-01-27

    We have synthesized certain indeno[1,2-b]quinoxaline derivatives for antiproliferative evaluation. Among them, 11-{[3-(dimethylamino)propoxy]imino}-N-[3-(dimethylamino) propyl]-11H-indeno[1,2-b]quinoxaline-6-carboxamide (10a) was active against the growth of MDA-MB231, PC-3, and Huh-7 with IC50 values of 0.87 (selectivity index, SI = 36.22), 0.82 (SI = 38.43), and 0.64 μM (SI = 49.23) respectively. Compound 10a was inactive against the growth of normal human fetal lung fibroblast cell line (MRC-5) with an IC50 value of 31.51 μM. Its analogs, 10b and 10c, were also active against the growth of MB231, PC-3, and Huh-7 with IC50 values of <1.0 μM in each case. Our results have also indicated compounds 10a-10c exhibited comparable inhibitory activities against topo I and topo II with the positive compound 2 at a concentration of 10 μM. Mechanism studies indicated that compound 10a induced cell cycle arrest at S phase via activation of caspase-3, -7 and an increase in the protein expression of Bad and Bax but a decrease in expression of Bcl-2 and PARP, which consequently cause cell death. In addition, compound 10a attenuated the levels of phosphorylated Src, Akt-1, and Akt-2 protein levels but did not affect the total protein expression of Akt. We have also implanted human hepatocellular carcinoma cells into the yolk sac of zebrafish larvae and incubated larvae with various concentrations of 10a. Our results of the zebrafish xenograft assay confirmed the anti-tumor effect of 10ain vivo. PMID:26686931

  9. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  10. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  11. Phenylated Polyimides With Greater Solubility

    NASA Technical Reports Server (NTRS)

    Harris, Frank W.

    1991-01-01

    In experiments, 3,6-diphenylpyromellitic dianhydride monomer prepared and polymerized with several different diamines. Polyimides with pendent phenyl groups along polymer backbones considerably more soluble than PMDA-based materials. Increased solubility eases processing, providing increased potential use in variety of applications. Because most polymers soluble in organic solvents, usable in microelectronics applications. Excellent thermal stabilities and high transition temperatures make them ideally suited. Many polymers extremely rigid and useful as reinforcing polymers in molecular composites. More flexible compositions useful as matrix resins in carbon-reinforced composites.

  12. Activity of a novel quinoxaline derivative against human immunodeficiency virus type 1 reverse transcriptase and viral replication.

    PubMed Central

    Kleim, J P; Bender, R; Billhardt, U M; Meichsner, C; Riess, G; Rösner, M; Winkler, I; Paessens, A

    1993-01-01

    S-2720 [6-chloro-3,3-dimethyl-4-(isopropenyloxycarbonyl)-3,4- dihydroquinoxalin-2(1H)-thione], a quinoxaline derivative, was found to be a very potent inhibitor of both human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) activity and HIV-1 replication in tissue culture. Like other nonnucleoside RT inhibitors, S-2720 does not affect the HIV-2 RT. A S-2720-resistant virus was selected and shown to possess a mutation within the RT-coding region that has not previously been described. Notably, this mutation gives rise to a dramatic decrease in enzyme activity. S-2720, therefore, belongs to a new class of RT inhibitors that bind differently to the RT than other known nonnucleoside RT inhibitors. As no toxic effects were observed with S-2720 in mice, these quinoxaline derivatives deserve further evaluation to prove their potency as possible therapeutic agents for HIV-1 infection. PMID:7692812

  13. A simple strategy to the side chain functionalization on the quinoxaline unit for efficient polymer solar cells.

    PubMed

    Yuan, Jun; Qiu, Lixia; Zhang, Zhiguo; Li, Yongfang; He, Yuehui; Jiang, Lihui; Zou, Yingping

    2016-05-25

    A new tetrafluoridequinoxaline electron accepting block from a quinoxaline core, which is substituted with a fluorine atom onto its backbone and side chains, was designed. A new copolymer (PBDTT-ffQx) was synthesized from tetrafluoridequinoxaline and benzodithiophene. The copolymer was characterized in detail. The photovoltaic properties were well investigated. A high PCE of 8.6% based on the single junction device was obtained. PMID:27025274

  14. Superacid-promoted additions involving vinyl-substituted pyrimidines, quinoxalines, and quinazolines: mechanisms correlated to charge distributions

    PubMed Central

    Zhang, Yiliang; Sheets, Matthew R.; Raja, Erum K.; Boblak, Kenneth N.

    2011-01-01

    The superacid-promoted reactions of vinyl-substituted N-heterocycles have been studied. Diprotonated pyrimidines, quinoxalines, and quinazolines exhibit an unusual regioelectronic effect that controls the type of addition reaction observed. Depending on the ring position of the vinyl-substituent, either conjugate addition or Markovnikov addition occurs. The mode of addition has been shown to correlate well to NBO calculated charges. PMID:21548654

  15. Conjugated poly(fluorene-quinoxaline) for fluorescence imaging and chemical detection of nerve agents with its paper-based strip.

    PubMed

    Jo, Seonyoung; Kim, Daigeun; Son, Sang-Ho; Kim, Yongkyun; Lee, Taek Seung

    2014-01-22

    Conjugated polymer of poly(fluorene-co-quinoxaline) was synthesized via Suzuki coupling polymerization. The emission color of the polymer can be tuned depending on the concentration of the polymer in solution. A low-energy bandgap is observed both in the concentrated solution and in the solid state, caused by aggregation of the polymer chains, resulting in long wavelength emission from the quinoxaline moiety, while short wavelength emission can be seen in diluted, well-dissolved solution. The presence of quinoxaline units enables us to demonstrate fluorescence switching and imaging. Paper-based strips containing the polymer are prepared via simple immersion of filter paper in the polymer solution for practical use in the detection of nerve agents. The emission of the paper-based strip is quenched upon exposure to diethyl chlorophosphate (DCP), a nerve agent simulant, and the initial emission intensity can be almost restored by treatment with aqueous sodium hydroxide solution, making a possible reversible paper-based sensor. PMID:24372409

  16. Trimerization of Phenyl Cyanate Ester

    NASA Astrophysics Data System (ADS)

    Pallaka, Madhusudhan Reddy; Simon, Sindee L.

    2015-03-01

    The kinetics of phenyl cyanate ester trimerization is studied in the bulk using differential scanning calorimetry. Dynamic experiments for different heating rates are analyzed for the activation energy using the model-free Kissinger-Akahira-Sunose(KAS) isoconversion method. The activation energy and other kinetic parameters are also obtained by fitting the dynamic data to a first order autocatalytic reaction model, which well describes the experimental data. The activation energy obtained from the KAS isoconversion method (70.1 kJ/mol) is in good agreement with that obtained from the kinetic model (73.2 kJ/mol) and is much lower than the more bulky cyanate esters studied in our laboratory, which have activation energies of approximately 95 kJ/mol. In addition, the rate constant for the phenyl cyanate ester is one to two orders higher than the bulkier cyanate esters in the temperature range of 200 to 300°C. Further elucidation of the dynamic experiments revealed a strong dependence of the reaction kinetics on the sample weight. Future work aims to understand this finding.

  17. Vertical and lateral morphology effects on solar cell performance for a thiophene–quinoxaline copolymer:PC 70BM blend

    SciTech Connect

    Hansson, Rickard; Ericsson, Leif K. E.; Holmes, Natalie P.; Rysz, Jakub; Opitz, Andreas; Campoy-Quiles, Mariano; Wang, Ergang; Barr, Matthew G.; Kilcoyne, A. L. David; Zhou, Xiaojing; Dastoor, Paul; Moons, Ellen

    2015-02-13

    The distribution of electron donor and acceptor in the active layer is known to strongly influence the electrical performance of polymer solar cells for most of the high performance polymer:fullerene systems. The formulation of the solution from which the active layer is spincoated plays an important role in the quest for morphology control. We have studied how the choice of solvent and the use of small amounts of a low vapour pressure additive in the coating solution influence the film morphology and the solar cell performance for blends of poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1) and [6,6]-phenyl C71-butyric acid methyl ester (PC70BM). We have investigated the lateral morphology using atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM), the vertical morphology using dynamic secondary ion mass spectrometry (d-SIMS) and variable-angle spectroscopic ellipsometry (VASE), and the surface composition using near-edge X-ray absorption fine structure (NEXAFS). The lateral phase-separated domains observed in films spincoated from single solvents, increase in size with increasing solvent vapour pressure and decreasing PC70BM solubility, but are not observed when 1-chloronaphthalene (CN) is added. A strongly TQ1-enriched surface layer is formed in all TQ1:PC70BM blend films and rationalized by surface energy differences. The photocurrent and power conversion efficiency strongly increased upon the addition of CN, while the leakage current decreased by one to two orders of magnitude. The higher photocurrent correlates with the finer lateral structure and stronger TQ1-enrichment at the interface with the electron-collecting electrode. This indicates that the charge transport and collection are not hindered by this polymer-enriched surface layer. Neither the open-circuit voltage nor the series resistance of the devices are sensitive to the differences in morphology.

  18. Quinoxaline 1,4-di-N-Oxides: Biological Activities and Mechanisms of Actions

    PubMed Central

    Cheng, Guyue; Sa, Wei; Cao, Chen; Guo, Liangliang; Hao, Haihong; Liu, Zhenli; Wang, Xu; Yuan, Zonghui

    2016-01-01

    Quinoxaline 1,4-di-N-oxides (QdNOs) have manifold biological properties, including antimicrobial, antitumoral, antitrypanosomal and antiinflammatory/antioxidant activities. These diverse activities endow them broad applications and prospects in human and veterinary medicines. As QdNOs arouse widespread interest, the evaluation of their medicinal chemistry is still in progress. In the meantime, adverse effects have been reported in some of the QdNO derivatives. For example, genotoxicity and bacterial resistance have been found in QdNO antibacterial growth promoters, conferring urgent need for discovery of new QdNO drugs. However, the modes of actions of QdNOs are not fully understood, hindering the development and innovation of these promising compounds. Here, QdNOs are categorized based on the activities and usages, among which the antimicrobial activities are consist of antibacterial, antimycobacterial and anticandida activities, and the antiprotozoal activities include antitrypanosomal, antimalarial, antitrichomonas, and antiamoebic activities. The structure-activity relationship and the mode of actions of each type of activity of QdNOs are summarized, and the toxicity and the underlying mechanisms are also discussed, providing insight for the future research and development of these fascinating compounds. PMID:27047380

  19. Spectroscopic properties and the catalytic activity of new organo-lead supramolecular coordination polymer containing quinoxaline

    NASA Astrophysics Data System (ADS)

    Etaiw, Safaa El-din H.; Abdou, Safaa N.

    2015-01-01

    The 3D-supramolecular coordination polymer (SCP) 3∞[ Cu2(CN)3(Me3Pb)(qox)], 1, as the first example of the CuCN SCP containing the (Me3Pb) fragment, was explored to investigate its catalytic and photo-catalytic activities. The structure of 1 contains two chemically identical but crystallographically different [Cu2(CN)3ṡMe3Pbṡqox]2 units with four Cu(I) sites assuming distorted TP-3 geometry. Two non-linear chains of equal abundance are formed producing corrugated parallel chains which are connected laterally by quinoxaline creating 2D-layers which are arranged parallel in an (AB⋯AB⋯AB)n fashion forming 3D-network. IR, mass, electronic absorption and fluorescence spectra are also investigated. The SCP 1 is diamagnetic and exhibits good catalytic and photo-catalytic activities for the degradation of methylene blue (MB). The reaction is first order with respect to MB dye. The irradiation of the reaction with UV-light enhanced the rate of MB mineralization. The efficiency of recycled the 1 and the mechanism of degradation of MB dye were investigated.

  20. Spectroscopic properties and the catalytic activity of new organo-lead supramolecular coordination polymer containing quinoxaline.

    PubMed

    Etaiw, Safaa El-din H; Abdou, Safaa N

    2015-01-25

    The 3D-supramolecular coordination polymer (SCP) (3)∞[ Cu2(CN)3(Me3Pb)(qox)], 1, as the first example of the CuCN SCP containing the (Me3Pb) fragment, was explored to investigate its catalytic and photo-catalytic activities. The structure of 1 contains two chemically identical but crystallographically different [Cu2(CN)3⋅Me3Pb⋅qox]2 units with four Cu(I) sites assuming distorted TP-3 geometry. Two non-linear chains of equal abundance are formed producing corrugated parallel chains which are connected laterally by quinoxaline creating 2D-layers which are arranged parallel in an (AB⋯AB⋯AB)n fashion forming 3D-network. IR, mass, electronic absorption and fluorescence spectra are also investigated. The SCP 1 is diamagnetic and exhibits good catalytic and photo-catalytic activities for the degradation of methylene blue (MB). The reaction is first order with respect to MB dye. The irradiation of the reaction with UV-light enhanced the rate of MB mineralization. The efficiency of recycled the 1 and the mechanism of degradation of MB dye were investigated. PMID:25124847

  1. Further investigations into the genotoxicity of quinoxaline-di-N-oxides and their primary metabolites.

    PubMed

    Liu, Qianying; Zhang, Jianwu; Luo, Xun; Ihsan, Awais; Liu, Xianglian; Dai, Menghong; Cheng, Guyue; Hao, Haihong; Wang, Xu; Yuan, Zonghui

    2016-07-01

    Quinoxaline-di-N-oxides (QdNOs) are potential antibacterial agents with a wide range of biological properties. Quinocetone (QCT), carbadox (CBX), olaquindox (OLA), mequindox (MEQ) and cyadox (CYA) are classical QdNOs. Though the genotoxicity of parent drugs has been evaluated, the genotoxicity of their primary N → O reduced metabolites remains unclear. In the present study, a battery of four different short-term tests, mouse lymphoma assay (MLA), Ames test, chromosomal aberration assay in vitro and bone marrow erythrocyte micronucleus assay in vivo was carried out to investigate the genotoxicity of the six primary N → O reduced metabolites. Additionally, the genotoxicity of five parent drugs was evaluated by the MLA. Strong genotoxicity of N1-MEQ, B-MEQ and B-CBX was found in three of the assays but not in the Ames assay, and the rank order was N1-MEQ>B-MEQ>B-CBX that is consistent with prototype QdNOs. Negative results for the five QdNOs were noted in the MLA. We present for the first time a comparison of the genotoxicity of primary N → O reduced metabolites, and evaluate the ability of five QdNOs to cause mutations in the MLA. The present study demonstrates that metabolites are involved in genetic toxicity mediated by QdNOs, and improve the prudent use of QdNOs for public health. PMID:27170491

  2. Potent and selective inhibition of polycythemia by the quinoxaline JAK2 inhibitor NVP-BSK805.

    PubMed

    Baffert, Fabienne; Régnier, Catherine H; De Pover, Alain; Pissot-Soldermann, Carole; Tavares, Gisele A; Blasco, Francesca; Brueggen, Josef; Chène, Patrick; Drueckes, Peter; Erdmann, Dirk; Furet, Pascal; Gerspacher, Marc; Lang, Marc; Ledieu, David; Nolan, Lynda; Ruetz, Stephan; Trappe, Joerg; Vangrevelinghe, Eric; Wartmann, Markus; Wyder, Lorenza; Hofmann, Francesco; Radimerski, Thomas

    2010-07-01

    The recent discovery of an acquired activating point mutation in JAK2, substituting valine at amino acid position 617 for phenylalanine, has greatly improved our understanding of the molecular mechanism underlying chronic myeloproliferative neoplasms. Strikingly, the JAK2(V617F) mutation is found in nearly all patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia and primary myelofibrosis. Thus, JAK2 represents a promising target for the treatment of myeloproliferative neoplasms and considerable efforts are ongoing to discover and develop inhibitors of the kinase. Here, we report potent inhibition of JAK2(V617F) and JAK2 wild-type enzymes by a novel substituted quinoxaline, NVP-BSK805, which acts in an ATP-competitive manner. Within the JAK family, NVP-BSK805 displays more than 20-fold selectivity towards JAK2 in vitro, as well as excellent selectivity in broader kinase profiling. The compound blunts constitutive STAT5 phosphorylation in JAK2(V617F)-bearing cells, with concomitant suppression of cell proliferation and induction of apoptosis. In vivo, NVP-BSK805 exhibited good oral bioavailability and a long half-life. The inhibitor was efficacious in suppressing leukemic cell spreading and splenomegaly in a Ba/F3 JAK2(V617F) cell-driven mouse mechanistic model. Furthermore, NVP-BSK805 potently suppressed recombinant human erythropoietin-induced polycythemia and extramedullary erythropoiesis in mice and rats. PMID:20587663

  3. 3-[2-(3-Methyl­quinoxalin-2-yl­oxy)eth­yl]-1,3-oxazolidin-2-one

    PubMed Central

    Ahoya, Caleb Anothane; Bouhfid, Rachid; Daouda, Ballo; Essassi, El Mokhtar; El Ammari, Lahcen

    2010-01-01

    Two isomers were isolated during the reaction between 3-methyl­quinoxalin-2-one and bis­(2-chloro­ethyl)amine hydro­chloride. The crystal structure of one isomer has already been reported [Caleb, Bouhfid, Essassi & El Ammari (2009). Acta Cryst. E65, o2024–o2025], while that of the second isomer is the subject of this work. The title compound, C14H15N3O3, has a new structure containing oxazolidine and quinoxaline rings linked by an eth­oxy group. The main difference between the two isomers is the position of the oxazolidine group with respect to the quinoxaline system. The dihedral angle between the fused planar rings and the oxazolidin-2-one ring is 41.63 (8)° in the title mol­ecule. PMID:21579110

  4. Highly efficient synthesis of quinoxaline derivatives from 1,2-benzenediamine and [Formula: see text]-aminoxylated 1,3-dicarbonyl compounds.

    PubMed

    Yan, Jianwei; Xu, Yanhong; Zhuang, Fangfang; Tian, Jie; Zhang, Guisheng

    2016-05-01

    Simple and efficient synthetic procedures for the preparation of quinoxaline, pyrazine, pyridopyrazine, and benzoxazin-2-one derivatives were developed. The one-pot cascade process involves the acidic elimination of [Formula: see text]-aminoxylated dicarbonyl compounds to generate 1,2,3-tricarbonyl compounds and subsequent condensation with 1,4-N,N or -N,O dinucleophiles to afford quinoxaline, pyrazine, pyridopyrazine, and benzoxazin-2-one scaffolds. All the proposed processes do not need extra catalysts, dry solvents, or harsh reaction conditions. PMID:26797715

  5. In vitro and in vivo anti-glioma activity of a chalcone-quinoxaline hybrid.

    PubMed

    Loch-Neckel, Gecioni; Bicca, Maíra Assunção; Leal, Paulo César; Mascarello, Alessandra; Siqueira, Jarbas Mota; Calixto, João B

    2015-01-27

    Chalcones are important compounds that exhibit multiple biological activities, including anti-inflammatory, antimitotic and antibacterial properties. In the present study, we have analyzed the potential anti-cancer activity of a chalcone named N9 (a hybrid chalcone-quinoxaline compound) using in vitro and in vivo experimental glioma models. Here, we report N9-induced inhibition of cell proliferation and also N9-induced cell death in a concentration-dependent manner in U87-MG glioma cells. These effects of N9 appear to be associated with its ability to inhibit the expression of cell cycle-associated proteins, and also the augmentation in the expression of the p21 (p21/Cip1) protein, a cyclin-dependent kinase inhibitor. Additionally, N9 also potentiates the production of the pro-apoptotic markers Bax and p53 via inhibition of MDM2. Moreover, our results show that N9 also significantly enhanced apoptosis of U87-MG cells with disruption of mitochondrial membrane potential, generation of ROS and caspase-9 activation. In vivo experiments carried out in a murine xenograft model of U87-MG revealed that N9 produced a significant reduction of tumors volume when compared to vehicle treated mice. Collectively, data demonstrate that N9 possess in vitro and in vivo anti-cancer activity, an effect that seems to involve the induction of p53 and p21 proteins, as well as, the activation of mitochondrial apoptosis pathway associated with the inhibition of protein MDM2. Overall, this study suggests N9 is affecting a variety of intracellular pathways related to tumor apoptosis. Perhaps N9 or derivate molecules could represent new potential drugs for cancer therapeutics. PMID:25461314

  6. One-Pot Synthesis of Benzo[4,5]imidazo[2,1-a]isoquinolines and Isoquinolino[3,4-b]quinoxalines via Tandem Cyclization Strategies.

    PubMed

    Bagdasarian, Alex L; Nguyen, Huy H; Palazzo, Teresa A; Fettinger, James C; Haddadin, Makhluf J; Kurth, Mark J

    2016-05-01

    Two operationally simple one-pot protocols have been developed for the synthesis of amino-functionalized benzo[4,5]imidazo[2,1-a]isoquinolines and isoquinolino[3,4-b]quinoxalines. Optimization data and substrate scope for these atom-economical transformations, which engage commercially available o-phenylenediamines and o-cyanobenzaldehydes, are discussed. PMID:27030441

  7. A one-pot catalyst-free synthesis of functionalized pyrrolo[1,2-a]quinoxaline derivatives from benzene-1,2-diamine, acetylenedicarboxylates and ethyl bromopyruvate.

    PubMed

    Piltan, Mohammad; Moradi, Loghman; Abasi, Golaleh; Zarei, Seyed Amir

    2013-01-01

    The catalyst-free multicomponent reaction of 1,2-diaminobenzene, dialkyl acetylenedicarboxylates, and ethyl bromopyruvate forms pyrrolo[1,2-a]quinoxaline derivatives in good yields. Ethylenediamine also reacts under similar conditions to produce new pyrrolo[1,2-a]pyrazine derivatives. PMID:23616791

  8. Synthesis and characterization of different zinc(II) oxide nano-structures from two new zinc(II)-Quinoxaline coordination polymers

    NASA Astrophysics Data System (ADS)

    Molaei, Fatemeh; Bigdeli, Fahime; Morsali, Ali; Joo, Sang Woo; Bruno, Giuseppe; Rudbari, Hadi Amiri

    2015-09-01

    Two new zinc(II) coordination polymers, [Zn(Quinoxaline)(NO3)2(H2O)2]nṡQuinoxaline·H2O (1) and [Zn(Quinoxaline)2(Br)2]n (2), Quinoxaline = Benzopyrazine, have been synthesized and characterized by IR spectroscopy. Compounds 1 and 2 were structurally characterized by single crystal X-ray diffraction and are one-dimensional coordination polymers with coordination environment of octahedral and tetrahedral respectively. Nanostructures of zinc(II) oxide were obtained by thermolyses of compound 1 in oleic acid, calcination of compound 1 at 500 °C under air atmosphere and sol-gel processes. Also, nanopowders of zinc(II) oxide were obtained by calcination of compound 2 at 450 and 550 °C. The nanomaterials were characterized by scanning electron microscopy and X-ray powder diffraction (XRD). The thermal stability of compounds 1 and 2 both their bulk were studied by thermo-gravimetric (TGA) and differential thermal analyses (DTA). This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.

  9. Ferrocene-quinoxaline Y-shaped chromophores as fascinating second-order NLO building blocks for long lasting highly active SHG polymeric films.

    PubMed

    Senthilkumar, Kabali; Thirumoorthy, Krishnan; Dragonetti, Claudia; Marinotto, Daniele; Righetto, Stefania; Colombo, Alessia; Haukka, Matti; Palanisami, Nallasamy

    2016-07-26

    The first example of a Y-shaped ferrocene quinoxaline derivative with a surprisingly high and stable second harmonic generation (SHG) response in composite polymeric films is reported. The interesting quadratic hyperpolarizability values of different substituted Y-shaped chromophores are also investigated in solution by the EFISH technique. PMID:27402322

  10. Coordinated assembly of a new 3D mesoporous Fe₃O₄@Cu₂O-graphene oxide framework as a highly efficient and reusable catalyst for the synthesis of quinoxalines.

    PubMed

    Wang, Zhiyi; Hu, Guowen; Liu, Jian; Liu, Weisheng; Zhang, Haoli; Wang, Baodui

    2015-03-25

    A new three-dimensional (3D) mesoporous hybrid framework was synthesized by coordinated layer-by-layer assembly between nanosheets of reduced graphene oxide and Fe3O4@Cu2O. This 3D mesoporous framework shows an excellent catalytic performance with a remarkable activity, selectivity (>99%), and strong durability in the synthesis of quinoxalines. PMID:25712163

  11. 40 CFR 721.3430 - 4-Bromophenyl phenyl ether.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 4-Bromophenyl phenyl ether. 721.3430... Substances § 721.3430 4-Bromophenyl phenyl ether. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance 4-bromophenyl phenyl ether (CAS No. 101-55-3) is subject to...

  12. 40 CFR 721.3430 - 4-Bromophenyl phenyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 4-Bromophenyl phenyl ether. 721.3430... Substances § 721.3430 4-Bromophenyl phenyl ether. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance 4-bromophenyl phenyl ether (CAS No. 101-55-3) is subject to...

  13. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject...

  14. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject...

  15. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject...

  16. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject...

  17. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject...

  18. Ultraviolet photodissociation dynamics of the phenyl radical

    SciTech Connect

    Song Yu; Lucas, Michael; Alcaraz, Maria; Zhang Jingsong; Brazier, Christopher

    2012-01-28

    Ultraviolet (UV) photodissociation dynamics of jet-cooled phenyl radicals (C{sub 6}H{sub 5} and C{sub 6}D{sub 5}) are studied in the photolysis wavelength region of 215-268 nm using high-n Rydberg atom time-of-flight and resonance enhanced multiphoton ionization techniques. The phenyl radicals are produced from 193-nm photolysis of chlorobenzene and bromobenzene precursors. The H-atom photofragment yield spectra have a broad peak centered around 235 nm and are in good agreement with the UV absorption spectra of phenyl. The H + C{sub 6}H{sub 4} product translational energy distributions, P(E{sub T})'s, peak near {approx}7 kcal/mol, and the fraction of average translational energy in the total excess energy, , is in the range of 0.20-0.35 from 215 to 268 nm. The H-atom product angular distribution is isotropic. The dissociation rates are in the range of 10{sup 7}-10{sup 8} s{sup -1} with internal energy from 30 to 46 kcal/mol above the threshold of the lowest energy channel H +o-C{sub 6}H{sub 4} (ortho-benzyne), comparable with the rates from the Rice-Ramsperger-Kassel-Marcus theory. The results from the fully deuterated phenyl radical are identical. The dissociation mechanism is consistent with production of H +o-C{sub 6}H{sub 4}, as the main channel from unimolecular decomposition of the ground electronic state phenyl radical following internal conversion of the electronically excited state.

  19. High-performance fluorescence sensing of lanthanum ions (La(3+)) by a polydentate pyridyl-based quinoxaline derivative.

    PubMed

    Zhao, Qiang; Liu, Xiu-Ming; Li, Huan-Rong; Zhang, Ying-Hui; Bu, Xian-He

    2016-06-28

    A polydentate pyridyl derivative, 2,3,6,7,10,11-hexa(2-pyridyl)-dipyrazino [2,3-f:2',3'-h]quinoxaline (HPDQ), exhibits a high-performance fluorescence response to La(3+) with an ∼65 nm redshifted emission wavelength and 38 fold enhanced intensity, in contrast to its weakened emission for other lanthanide ions. The final La(3+) coordination complex in solution has a stoichiometric ratio of 1 : 3 of ligand-to-metal, as testified by the Job's plot and single crystal structure analyses. The red shift of the luminescence emission as well as UV-vis absorption was rationalized in terms of the change of the electron structure as indicated by nuclear magnetic titration, electrochemical experiment and density functional theoretical calculation, while the significant enhancement of emission was attributed to the enhanced π conjugated extent of HPDQ caused by La(3+) coordination. PMID:27297084

  20. Synthesis of quinoxalines or quinolin-8-amines from N-propargyl aniline derivatives employing tin and indium chlorides.

    PubMed

    Aichhorn, Stefan; Himmelsbach, Markus; Schöfberger, Wolfgang

    2015-09-28

    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. PMID:26280508

  1. Discovery and Optimization of Macrocyclic Quinoxaline-pyrrolo-dihydropiperidinones as Potent Pim-1/2 Kinase Inhibitors.

    PubMed

    Cee, Victor J; Chavez, Frank; Herberich, Bradley; Lanman, Brian A; Pettus, Liping H; Reed, Anthony B; Wu, Bin; Wurz, Ryan P; Andrews, Kristin L; Chen, Jie; Hickman, Dean; Laszlo, Jimmy; Lee, Matthew R; Guerrero, Nadia; Mattson, Bethany K; Nguyen, Yen; Mohr, Christopher; Rex, Karen; Sastri, Christine E; Wang, Paul; Wu, Qiong; Wu, Tian; Xu, Yang; Zhou, Yihong; Winston, Jeffrey T; Lipford, J Russell; Tasker, Andrew S; Wang, Hui-Ling

    2016-04-14

    The identification of Pim-1/2 kinase overexpression in B-cell malignancies suggests that Pim kinase inhibitors will have utility in the treatment of lymphoma, leukemia, and multiple myeloma. Starting from a moderately potent quinoxaline-dihydropyrrolopiperidinone lead, we recognized the potential for macrocyclization and developed a series of 13-membered macrocycles. The structure-activity relationships of the macrocyclic linker were systematically explored, leading to the identification of 9c as a potent, subnanomolar inhibitor of Pim-1 and -2. This molecule also potently inhibited Pim kinase activity in KMS-12-BM, a multiple myeloma cell line with relatively high endogenous levels of Pim-1/2, both in vitro (pBAD IC50 = 25 nM) and in vivo (pBAD EC50 = 30 nM, unbound), and a 100 mg/kg daily dose was found to completely arrest the growth of KMS-12-BM xenografts in mice. PMID:27096050

  2. Crystal structure of 1,3-bis­(2,3-di­methyl­quinoxalin-6-yl)benzene

    PubMed Central

    Diesendruck, Charles E.; Rubin, Gabrielle; Bertke, Jeffery A.; Gray, Danielle L.; Moore, Jeffrey S.

    2015-01-01

    The title compound, C26H22N4 (I), was synthesized by C—H iridium-catalyzed borylation followed by Suzuki coupling. The mol­ecular structure of (I) consists of a central benzene ring with 3-di­methyl­quinoxalin-6-yl groups at the 1 and 3 positions. These 2,3-di­methyl­quinoxalin-6-yl groups twist significantly out of the plane of the benzene ring. There are inter­molecular π–π inter­actions which result in a two-dimensional extended structure. The layers extend parallel to the ab plane and stack along the c axis. PMID:26870397

  3. Synthesis, 3D-QSAR analysis and biological evaluation of quinoxaline 1,4-di-N-oxide derivatives as antituberculosis agents.

    PubMed

    Pan, Yuanhu; Li, Panpan; Xie, Shuyu; Tao, Yanfei; Chen, Dongmei; Dai, Menghong; Hao, Haihong; Huang, Lingli; Wang, Yulian; Wang, Liye; Liu, Zhenli; Yuan, Zonghui

    2016-08-15

    A series of quinoxaline 1,4-di-N-oxide derivatives variously substituted at C-2 position were synthesized and evaluated for in vitro antimycobacterial activity. Seventeen compounds exhibited potential activity (MIC ⩽6.25μg/mL) against Mycobacterium tuberculosis (H37Rv), in particular the compounds 3d and 3j having an MIC value of 0.39μg/mL. None of the compounds exhibited cytotoxicity when using an MTT assay in VERO cells. To further investigate the structure-activity relationship, CoMFA (q(2)=0.507, r(2)=0.923) and CoMSIA (q(2)=0.665, r(2)=0.977) models were performed on the basis of antimycobacterial activity data. The 3D-QSAR study of these compounds can provide useful information for further rational design of novel quinoxaline 1,4-di-N-oxides for treatment of tuberculosis. PMID:27426298

  4. Design, synthesis, and biological evaluation of 3-vinyl-quinoxalin-2(1H)-one derivatives as novel antitumor inhibitors of FGFR1

    PubMed Central

    Liu, Zhiguo; Yu, Shufang; Chen, Di; Shen, Guoliang; Wang, Yu; Hou, Leping; Lin, Dan; Zhang, Jinsan; Ye, Faqing

    2016-01-01

    FGFR1 is well known as a molecular target in anticancer drug design. TKI258 plays an important role in RTK inhibitors. Utilizing TKI258 as a lead compound that contains a quinazolinone nucleus, we synthesized four series of 3-vinyl-quinoxalin-2(1H)-one derivatives, a total of 27 compounds. We further evaluated these compounds for FGFR1 inhibition ability as well as cytotoxicity against four cancer cell lines (H460, B16-F10, Hela229, and Hct116) in vitro. Some compounds displayed good-to-excellent potency against the four tested cancer cell lines compared with TKI258. Structure–activity relationship analyses indicated that small substituents at the side chain of the 3-vinyl-quinoxalin-2(1H)-one were more effective than large substituents. Lastly, we used molecular docking to obtain further insight into the interactions between the compounds and FGFR1. PMID:27217720

  5. Design, synthesis, and biological evaluation of 3-vinyl-quinoxalin-2(1H)-one derivatives as novel antitumor inhibitors of FGFR1.

    PubMed

    Liu, Zhiguo; Yu, Shufang; Chen, Di; Shen, Guoliang; Wang, Yu; Hou, Leping; Lin, Dan; Zhang, Jinsan; Ye, Faqing

    2016-01-01

    FGFR1 is well known as a molecular target in anticancer drug design. TKI258 plays an important role in RTK inhibitors. Utilizing TKI258 as a lead compound that contains a quinazolinone nucleus, we synthesized four series of 3-vinyl-quinoxalin-2(1H)-one derivatives, a total of 27 compounds. We further evaluated these compounds for FGFR1 inhibition ability as well as cytotoxicity against four cancer cell lines (H460, B16-F10, Hela229, and Hct116) in vitro. Some compounds displayed good-to-excellent potency against the four tested cancer cell lines compared with TKI258. Structure-activity relationship analyses indicated that small substituents at the side chain of the 3-vinyl-quinoxalin-2(1H)-one were more effective than large substituents. Lastly, we used molecular docking to obtain further insight into the interactions between the compounds and FGFR1. PMID:27217720

  6. Single-layer electroluminescent devices based on fluorene-1H-pyrazolo[3,4-b]quinoxaline co-polymers

    NASA Astrophysics Data System (ADS)

    Pokladko-Kowar, Monika; Danel, Andrzej; Chacaga, Łukasz

    2013-11-01

    A fluorene based copolymer was synthesized for electroluminescent application. To the main chain of polymer the nitrogen heterocyclic, 1H-pyrazolo[3,4-b]quinoxaline, unit was introduced. The incorporation of this derivative tuned the emission from the blue to yellow-green one. A simple, single layered device was fabricated with the configuration ITO/PEDOT/co-poly-FLU-PQX/Ca/Mg.

  7. Cytochrome P450-Mediated Metabolism and DNA Binding of 2-Amino-1,7-dimethylimidazo[4,5-g]quinoxaline and its Carcinogenic Isomer 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline in Mice

    PubMed Central

    Turesky, Robert J.; Bessette, Erin E.; Dunbar, Deborah; Liberman, Rosa G.; Skipper, Paul L.

    2012-01-01

    2-Amino-1,7-dimethylimidazo[4,5-g]quinoxaline (MeIgQx) is a recently discovered heterocyclic aromatic amine (HAA) that is formed during the cooking of meats. MeIgQx is an isomer of 2-amino-3,8-dimethylmidazo[4,5-f]quinoxaline (MeIQx), a rodent carcinogen and possible human carcinogen that also occurs in cooked meats. MeIgQx is a bacterial mutagen but knowledge about its metabolism and carcinogenic potential is lacking. Metabolism studies on MeIgQx and MeIQx were conducted with human and mouse liver microsomes, and recombinant human P450s. DNA binding studies were also investigated in mice to ascertain the genotoxic potential of MeIgQx in comparison to MeIQx. Both HAAs underwent comparable rates of N-oxidation to form genotoxic N-hydroxylated metabolites with mouse liver microsomes (0.2 - 0.3 nmol/min/mg protein). The rate of N-oxidation of MeIQx was 4-fold greater than the rate of N-oxidation of MeIgQx with human liver microsomes (1.7 vs 0.4 nmol/min/mg protein). The rate of N-oxidation, by recombinant human P450 1A2, was comparable for both substrates (6 pmol/min/pmol P450 1A2). MeIgQx also underwent N-oxidation by human P450s 1A1 and 1B1 at appreciable rates, whereas MeIQx was poorly metabolized by these P450s. The potential of MeIgQx and MeIQx to form DNA adducts was assessed in female C57BL/6 mice given [14C]-MeIgQx (10 μCi, 9.68 mg/kg body wt) or [14C]-MeIQx (10 μCi, 2.13 mg/kg body wt). DNA adduct formation in liver, pancreas and colorectum was measured by accelerator mass spectrometry at 4, 24 or 48 h post-treatment. Variable levels of adducts were detected in all organs. The adduct levels were similar for both HAAs, when adjusted for dose, and ranged from 1 to 600 adducts per 107 nucleotides per mg/kg dose. Thus, MeIgQx undergoes metabolic activation and binds to DNA at levels that are comparable to MeIQx. Given the high amounts of MeIgQx formed in cooked meats, further investigations are warranted to assess the carcinogenic potential of this HAA. PMID

  8. Chemistry of polycyclic aromatic hydrocarbons formation from phenyl radical pyrolysis and reaction of phenyl and acetylene.

    PubMed

    Comandini, A; Malewicki, T; Brezinsky, K

    2012-03-15

    An experimental investigation of phenyl radical pyrolysis and the phenyl radical + acetylene reaction has been performed to clarify the role of different reaction mechanisms involved in the formation and growth of polycyclic aromatic hydrocarbons (PAHs) serving as precursors for soot formation. Experiments were conducted using GC/GC-MS diagnostics coupled to the high-pressure single-pulse shock tube present at the University of Illinois at Chicago. For the first time, comprehensive speciation of the major stable products, including small hydrocarbons and large PAH intermediates, was obtained over a wide range of pressures (25-60 atm) and temperatures (900-1800 K) which encompass the typical conditions in modern combustion devices. The experimental results were used to validate a comprehensive chemical kinetic model which provides relevant information on the chemistry associated with the formation of PAH compounds. In particular, the modeling results indicate that the o-benzyne chemistry is a key factor in the formation of multi-ring intermediates in phenyl radical pyrolysis. On the other hand, the PAHs from the phenyl + acetylene reaction are formed mainly through recombination between single-ring aromatics and through the hydrogen abstraction/acetylene addition mechanism. Polymerization is the common dominant process at high temperature conditions. PMID:22339468

  9. New Phenyl Propanoids from Cryptocarya bracteolata.

    PubMed

    Saidi, Nurdin; Morita, Hiroshi; Litaudon, Marc; Nafiah, Mohd Azlan; Awang, Khalijah; Mustanir

    2016-06-01

    Two new phenyl propanoids were extracted from the bark of Cryptocarya bracteolate Gamb., ethyl 3-(2'-hydroxy-3',4',5'-trimethoxyphenyl) propanoate (1) and ethyl 3-(2'-glucosyl-3',4',5'-trimethoxyphenyl)propanoate (2), together with seven known alkaloids, (+)-lirioferine (3), (+)-bracteoline (4), (+)-reticuline (5), (+)-reticulineN-oxide (6), (-)-norargemonine (7), (+)-bisnorargemonine (8) and atherolin (9). The structures of compounds were established through several spectroscopic methods; 1D and 2D-NMR, UV, IR and MS. PMID:27534124

  10. Assembly of Cu/Ag-quinoxaline-polyoxotungstate hybrids: Influence of Keggin and Wells-Dawson polyanions on the structure

    NASA Astrophysics Data System (ADS)

    Chi, Ying-Nan; Cui, Feng-Yun; Lin, Zheng-Guo; Xu, Yan; Ma, Xiao-Yu; Shen, Pan-Pan; Huang, Kun-Lin; Hu, Chang-Wen

    2013-03-01

    In order to investigate the influence of Keggin and Wells-Dawson polyoxometalates on the resultant structure, four new organic-inorganic hybrid compounds [Cu4(qx)5(SiW12O40)] (1), [Cu6(qx)6(P2W18O62)(H2O)1.5]·4.5H2O (2), [Ag4(qx)4(SiW12O40)(H2O)]·H2O (3), [Ag6(qx)6(P2W18O62)]·8H2O (4) (qx=quinoxaline) were synthesized and structurally characterized by single-crystal X-ray diffraction. In 1, the 2D layers are linked by the SiW12O404- (SiW12) anions to construct a 3D framework. When the Wells-Dawson type P2W18O626- (P2W18) is used, 2 is prepared, in which the 1D helical chains are connected by P2W18 to form a 3D network. In 3, two kinds of 1D metal-organic chains are connected by SiW12 clusters to construct a 3D framework. In 4, there are also two kinds of 1D chains one kind of 1D chain combines with P2W18 by the AgO weak interaction and the other kind is just metal-organic chain. In addition, the electrochemistry properties of compounds 1-4 have been studied.

  11. Synthesis, characterization, electrochemical and biological studies on some metal(II) Schiff base complexes containing quinoxaline moiety

    NASA Astrophysics Data System (ADS)

    Justin Dhanaraj, Chellaian; Johnson, Jijo

    2014-01-01

    Novel Co(II), Ni(II), Cu(II) and Zn(II) complexes of Schiff base derived from quinoxaline-2,3-(1,4H)-dione and 4-aminoantipyrine (QDAAP) were synthesized. The ligand and its complexes were characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, FTIR, UV-Vis., mass and 1H NMR spectral studies. The X band ESR spectrum of the Cu(II) complex at 300 and 77 K were also recorded. Thermal studies of the ligand and its complexes show the presence of coordinated water in the Ni(II) and Zn(II) complexes. The coordination behavior of QDAAP is also discussed. All the complexes are mono nuclear and tetrahedral geometry was found for Co(II) complex. For the Ni(II) and Zn(II) complexes, octahedral geometry was assigned and for the Cu(II) complex, square planar geometry has been suggested. The grain size of the complexes was estimated using powder XRD. The surface morphology of the compounds was studied using SEM analysis. Electrochemical behavior of the synthesized complexes in DMF at room temperature was investigated by cyclic voltammetry. The in vitro biological screening of QDAAP and its metal complexes were tested against bacterial species Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The fungal species include Aspergillus niger, Aspergillus flavus and Candida albicans. The DNA cleavage activity of QDAAP and its complexes were also discussed.

  12. Spectral characterization, electrochemical and anticancer studies on some metal(II) complexes containing tridentate quinoxaline Schiff base

    NASA Astrophysics Data System (ADS)

    Chellaian, Justin Dhanaraj; Johnson, Jijo

    2014-06-01

    Co(II), Ni(II), Cu(II) and Zn(II) complexes of a tridentate ONO donor Schiff base ligand derived from 3-(2-aminoethylamino)quinoxalin-2(1H)-one were synthesized. The ligand and its metal complexes were characterized using elemental analysis, molar conductance, IR, 1H NMR, mass, magnetic susceptibility, electronic spectra and ESR spectral studies. Electrochemical behavior of the synthesized compounds was studied using cyclic voltammetry. The grain size of the synthesized compounds was determined by powder XRD. The Schiff base and its complexes have been screened for their antimicrobial activities against the bacterial species E. coli, K. pneumoniae, P. aeruginosa and S. aureus; fungal species include, A. niger, and C. albicans by disc diffusion method. The results show that the complexes have higher activity than the free ligand. The interaction of the complexes with calf thymus DNA (CT DNA) has been investigated by electronic absorption method. Furthermore, the DNA cleavage activity of the complexes was studied using agarose gel electrophoresis. In vitro anticancer studies of the ligand and its complexes using MTT assay was also done.

  13. Systematic and Molecular Basis of the Antibacterial Action of Quinoxaline 1,4-Di-N-Oxides against Escherichia coli

    PubMed Central

    Cheng, Guyue; Li, Bei; Wang, Chenxi; Zhang, Hongfei; Liang, Guixia; Weng, Zhifei; Hao, Haihong; Wang, Xu; Liu, Zhenli; Dai, Menghong; Wang, Yulian; Yuan, Zonghui

    2015-01-01

    Quinoxaline 1,4-di-N-oxides (QdNOs) are widely known as potent antibacterial agents, but their antibacterial mechanisms are incompletely understood. In this study, the transcriptomic and proteomic profiles of Escherichia coli exposed to QdNOs were integratively investigated, and the results demonstrated that QdNOs mainly induced an SOS response and oxidative stress. Moreover, genes and proteins involved in the bacterial metabolism, cellular structure maintenance, resistance and virulence were also found to be changed, conferring bacterial survival strategies. Biochemical assays showed that reactive oxygen species were induced in the QdNO-treated bacteria and that free radical scavengers attenuated the antibacterial action of QdNOs and DNA damage, suggesting an oxidative-DNA-damage action of QdNOs. The QdNO radical intermediates, likely carbon-centered and aryl-type radicals, as identified by electron paramagnetic resonance, were the major radicals induced by QdNOs, and xanthine oxidase was one of the QdNO-activating enzymes. This study provides new insights into the action of QdNOs in a systematic manner and increases the current knowledge of bacterial physiology under antibiotic stresses, which may be of great value in the development of new antibiotic-potentiating strategies. PMID:26296207

  14. N,N′-Bis(pyridin-2-yl)benzene-1,4-diamine–quinoxaline (2/1)

    PubMed Central

    Wicher, Barbara; Gdaniec, Maria

    2011-01-01

    The asymmetric unit of the title compound, 2C16H14N4·C8H6N2, consits of one mol­ecule of N,N′-bis­(pyridin-2-yl)benzene-1,4-diamine (PDAB) and one half-mol­ecule of quinoxaline (QX) that is located around an inversion centre and disordered over two overlapping positions. The PDAB mol­ecule adopts a non-planar conformation with an E configuration at the two partially double exo C N bonds of the 2-pyridyl­amine units. In the crystal, these self-complementary units are N—H⋯N hydrogen bonded via a cyclic R 2 2(8) motif, creating tapes of PDAB mol­ecules extending along [010]. Inversion-related tapes are arranged into pairs through π–π stacking inter­actions between the benzene rings [centroid–centroid distance = 3.818 (1) Å] and the two symmetry-independent pyridine groups [centroid–centroid distance = 3.760 (1) Å]. The QX mol­ecules are enclosed in a cavity formed between six PDAB tapes. PMID:22199763

  15. Synthesis of Phenyl-Adducted Cyclodextrin through the Click Reaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new derivative of ß-cyclodextrin (CD) has been made incorporating the phenyl group through the use of click reaction. The resulting product exhibits a self-association phenomenon through the formation of inclusion compound between the phenyl group and CD. The product has been characterized by 1H...

  16. 40 CFR 721.536 - Halogenated phenyl alkane.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.536 Halogenated phenyl alkane. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as halogenated phenyl alkane (PMN P-89-867)...

  17. 27 CFR 21.121 - Phenyl mercuric benzoate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Phenyl mercuric benzoate. 21.121 Section 21.121 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.121 Phenyl mercuric benzoate....

  18. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  19. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  20. 27 CFR 21.121 - Phenyl mercuric benzoate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Phenyl mercuric benzoate. 21.121 Section 21.121 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.121 Phenyl mercuric benzoate....

  1. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  2. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  3. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  4. Binding mode of an α-amino acid-linked quinoxaline-2,3-dione analogue at glutamate receptor subtype GluK1.

    PubMed

    Demmer, Charles S; Møller, Charlotte; Brown, Patricia M G E; Han, Liwei; Pickering, Darryl S; Nielsen, Birgitte; Bowie, Derek; Frydenvang, Karla; Kastrup, Jette S; Bunch, Lennart

    2015-06-17

    Two α-amino acid-functionalized quinoxalines, 1a (CNG-10301) and 1b (CNG-10300), of a quinoxaline moiety coupled to an amino acid moiety were designed, synthesized, and characterized pharmacologically. While 1a displayed low affinity at native AMPA, KA, and NMDA receptors, and at homomeric GluK1,3 receptors, the affinity for GluK2 was in the midmicromolar range (Ki = 136 μM), 1b displayed low to midmicromolar range binding affinity at all the iGluRs (Ki = 9-126 μM). In functional experiments (outside-out patches excised from transfected HEK293T cells), 100 μM 1a partially blocked GluK1 (33% peak response), while GluK2 was unaffected (96% peak response). Furthermore, 1a was shown not to be an agonist at GluK1 and GluK2 at 100 μM. On the other hand, 100 μM 1b fully antagonized GluK1 (8% peak response) but only partially blocked GluK2 (33% peak response). An X-ray structure at 2.3 Å resolution of 1b in the GluK1-LBD (ligand-binding domain) disclosed an unexpected binding mode compared to the predictions made during the design phase; the quinoxaline moiety remains to act as an amino acid bioisostere, but the amino acid moiety is oriented into a new area within the GluK1 receptor. The structure of the GluK1-LBD with 1b showed a large variation in domain openings of the three molecules from 25° to 49°, demonstrating that the GluK1-LBD is capable of undergoing major domain movements. PMID:25856736

  5. A Ferrocene-Quinoxaline Derivative as a Highly Selective Probe for Colorimetric and Redox Sensing of Toxic Mercury(II) Cations

    PubMed Central

    Zapata, Fabiola; Caballero, Antonio; Molina, Pedro; Tarraga, Alberto

    2010-01-01

    A new chemosensor molecule 3 based on a ferrocene-quinoxaline dyad recognizes mercury (II) cations in acetonitrile solution. Upon recognition, an anodic shift of the ferrocene/ferrocenium oxidation peaks and a progressive red-shift (Δλ = 140 nm) of the low-energy band, are observed in its absorption spectrum. This change in the absorption spectrum is accompanied by a colour change from orange to deep green, which can be used for a “naked-eye” detection of this metal cation. PMID:22163528

  6. Mechanochemical solid-state synthesis of 2-aminothiazoles, quinoxalines and benzoylbenzofurans from ketones by one-pot sequential acid- and base-mediated reactions.

    PubMed

    Nagarajaiah, Honnappa; Mishra, Abhaya Kumar; Moorthy, Jarugu Narasimha

    2016-04-26

    α-Chloroketones - obtained by the atom-economical chlorination of ketones with trichloroisocyanuric acid (TCCA) in the presence of p-TSA under ball-milling conditions - were set up for a sequential base-mediated condensation reaction with thiourea/thiosemicarbazides, o-phenylenediamine and salicylaldehyde to afford 2-aminothiazoles, 2-hydrazinylthiazoles, quinoxalines and benzoylbenzofurans, respectively, in respectable yields. The viability of one-pot sequential acid- and base-mediated reactions in the solid state under ball-milling conditions is thus demonstrated. PMID:27072599

  7. New 1,4-di-N-oxide-quinoxaline-2-ylmethylene isonicotinic acid hydrazide derivatives as anti-Mycobacterium tuberculosis agents.

    PubMed

    Torres, Enrique; Moreno, Elsa; Ancizu, Saioa; Barea, Carlos; Galiano, Silvia; Aldana, Ignacio; Monge, Antonio; Pérez-Silanes, Silvia

    2011-06-15

    The increase in the prevalence of drug-resistant tuberculosis cases demonstrates the need of discovering new and promising compounds with antimycobacterial activity. As a continuation of our research and with the aim of identifying new antitubercular drugs candidates, a new series of quinoxaline 1,4-di-N-oxide derivatives containing isoniazid was synthesized and evaluated for in vitro anti-tuberculosis activity against Mycobacterium tuberculosis H37Rv strain. Moreover, various drug-like properties of new compounds were predicted. Taking into account the biological results and the promising drug-likeness profile of these compounds, make them valid leads for further experimental research. PMID:21570839

  8. Hypervalent iodine(iii)-promoted N-incorporation into N-aryl vinylogous carbamates to quinoxaline diesters: access to 1,4,5,8-tetraazaphenanthrene.

    PubMed

    Sagar, A; Vidaycharan, Shinde; Shinde, Anand H; Sharada, Duddu S

    2016-04-26

    A novel oxidative N-incorporation strategy for synthesis of quinoxaline diesters under metal-free conditions is described for the first time. The mild reaction conditions allow for this transformation via the formation of two C(sp(2))-N bonds utilizing cheaply available NaN3 as the N-atom source. N-Aryl vinylogous carbamates in this study undergo azidation at enamino C(sp(2))-H selectively. The robustness of this strategy is further demonstrated by the synthesis of a valuable 1,4,5,8-tetraazaphenanthrene derivative using a mild and convenient approach. PMID:27050385

  9. Studies on some metal complexes of quinoxaline based unsymmetric ligand: Synthesis, spectral characterization, in vitro biological and molecular modeling studies.

    PubMed

    Dhanaraj, Chellaian Justin; Johnson, Jijo

    2016-08-01

    Mononuclear Co(II), Ni(II), Cu(II) and Zn(II) complexes of an unsymmetric Schiff base ligand, 3-(-(3-(-3,5-dichloro-2-hydroxybenzylideneamino)propylimino)methyl)quinoxalin-2(1H) -one (L) were synthesized and characterized by various analytical and spectral techniques. The molar conductance values of metal complexes indicate non-electrolytic behavior of the metal complexes. The Schiff base act as tetra dentate ONNO donor ligand in Co(II), Ni(II), Zn(II) complexes and tridentate NNO donor in Cu(II) complex. Thermal stabilities of the newly synthesized compounds were determined by thermal analysis. Crystallinity, average grain size and unit cell parameters were determined from powder X-ray diffraction study. Electrochemical behaviors of the compounds were examined by cyclic voltammetry technique. The Schiff base and its complexes have been screened for their in vitro antimicrobial activities against some bacterial and fungal strains by disc diffusion method. The interaction of the compounds with calf thymus DNA (CT DNA) has been investigated by electronic absorption spectral titration and viscosity measurement (hydrodynamic) methods. Furthermore, the pUC18 DNA cleavage activities of the complexes have been explored. The compounds were also subjected to in vitro antioxidant, anticancer activity screening, druglikeness and bioactivity predictions using Molinspiration software. Molecular docking studies of the present compounds were carried out against B-DNA dodecamer d(CGCGAATTCGCG)2 and vascular endothelial growth factor receptor (VEGFR-2) kinase. Quantum chemical calculations were done with DFT method to determine the optimum geometry of the ligand and its metal complexes. From the quantum chemical parameters, the reactivity parameters of the compounds were established. PMID:27236046

  10. Assessing the reactivity of sodium alkyl-magnesiates towards quinoxaline: single electron transfer (SET) vs. nucleophilic alkylation processes.

    PubMed

    Livingstone, Zoe; Hernán-Gómez, Alberto; Baillie, Sharon E; Armstrong, David R; Carrella, Luca M; Clegg, William; Harrington, Ross W; Kennedy, Alan R; Rentschler, Eva; Hevia, Eva

    2016-04-14

    By exploring the reactivity of sodium butyl-magnesiate (1) supported by the bulky chelating silyl(bisamido) ligand {Ph2Si(NAr*)2}(2-) (Ar* = 2,6-iPr2-C6H3) towards Quinoxaline (Qx), the ability of this bimetallic system to effectively promote SET processes has been disclosed. Thus 1 executes the single-electron reduction of Qx affording complex (2) whose structure in the solid state contains two quinaxolyl radical anions Qx˙ stabilised within a dimeric magnesiate framework. Combining multinuclear NMR and EPR measurements with DFT calculations, new insights into the constitution of 2 in solution and its magnetic behaviour have been gained. Further evidence on the SET reactivity of 1 was found when it was reacted with nitroxyl radical TEMPO which furnished contacted ion pair sodium magnesiate [(Ph2Si(NAr*)2)Mg(TEMPO(-))Na(THF)3] (4) where both metals are connected by an alkoxide bridge, resulting from reduction of TEMPO. The role that the different ligands present in 1 can play in these new SET reactions has also been assessed. Using an amination approach, the Bu group in 1 can be replaced by the more basic amide TMP allowing the isolation of (3) which was characterised by multinuclear NMR and X-ray crystallography. (1)H NMR monitoring of the reaction of 3 with Qx showed its conversion to 2, leaving the hydrogen atoms of the heterocycle untouched. Contrastingly, using sodium homoalkyl magnesiate [NaMg(CH2SiMe3)3] (5) led to the chemoselective C2 alkylation of this heterocycle, suggesting that the presence of the steric stabiliser {Ph2Si(NAr*)2}(2-) on the mixed-metal reagent is required in order to facilitate the Qx reduction. PMID:26617325

  11. Essential oil phenyl propanoids. Useful as .OH scavengers?

    PubMed

    Taira, J; Ikemoto, T; Yoneya, T; Hagi, A; Murakami, A; Makino, K

    1992-01-01

    In order to search for radical scavengers which could be used as raw materials for cosmetics, phenyl propanoids (eugenol, isoeugenol, dehydrodieugenol, dehydrodieugenol B and coniferyl aldehyde) were examined for their hydroxyl radical (.OH) scavenging ability. A Fenton system was used to produce .OH. In order to see scavenging by these phenyl propanoids, competition reactions between a spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), and these phenyl propanoids for .OH were studied. The relative yield of the spin adduct of .OH (DMPO-OH) was measured by electron spin resonance spectroscopy. The approximate rate constants of the reactions between these phenyl propanoids and .OH estimated by measuring the reduced height of the ESR signals of DMPO-OH were found to be at least in the order of 10(9) M-1 s-1 (diffusion-controlled). Also, using the TBA tests, the reactions between .OH and several compounds reactive with .OH were investigated in the presence of the phenyl propanoids and it was found that the phenyl propanoids compete with such reactive compounds for .OH. These results indicate that these phenyl propanoids can be used as antioxidants for skin damage perhaps caused by .OH generated by UV-light. PMID:1318253

  12. 2-(7,8-Diphenyl-1H-imidazo[4,5-f]quinoxalin-2-yl)phenol methanol disolvate

    PubMed Central

    Fun, Hoong-Kun; Kia, Reza; Raithby, Paul R.

    2008-01-01

    The title compound, C27H18N4O·2CH4O, is a unsymmetrically substituted quinoxaline. An intra­molecular O—H⋯N hydrogen bond involving the hydr­oxy and imino groups generates an S(6) ring motif. Inter­molecular C—H⋯O and N—H⋯O hydrogen bonds form an R 2 1(7) ring motif involving a methanol O atom and two H atoms of the imidazole and benzene rings, respectively. The latter links neighbouring mol­ecules into one-dimensional extended chains along the a axis. The two benzene rings are inclined towards each other, as indicated by the dihedral angle of 52.13 (10)°. The phenol ring is almost coplanar with the basic quinoxaline unit, making a dihedral angle of 2.43 (6)°. The short distances between the centroids of the five- and six-membered rings prove the existence of π–π inter­actions [centroid–centroid distances = 3.5234 (9)–3.7885 (10) Å]. The crystal structure is stabilized by intra­molecular O—H⋯N, inter­molecular O—H⋯O, N—H⋯O and C—H⋯O (× 2) hydrogen bonds and weak inter­molecular C—H⋯π and π–π inter­actions. PMID:21201724

  13. Iron-Catalyzed Intramolecular C(sp(2))-N Cyclization of 1-(N-Arylpyrrol-2-yl)ethanone O-Acetyl Oximes toward Pyrrolo[1,2-a]quinoxaline Derivatives.

    PubMed

    Zhang, Zhiguo; Li, Junlong; Zhang, Guisheng; Ma, Nana; Liu, Qingfeng; Liu, Tongxin

    2015-07-01

    An efficient and convenient iron-catalyzed protocol has been developed for the synthesis of substituted pyrrolo[1,2-a]quinoxalines from 1-(N-arylpyrrol-2-yl)ethanone O-acetyl oximes through N-O bond cleavage and intramolecular directed C-H arylation reactions in acetic acid. PMID:26057737

  14. Dipolar Dyes with a Pyrrolo[2,3-b]quinoxaline Skeleton Containing a Cyano Group and a Bridged Tertiary Amino Group: Synthesis, Solvatofluorochromism, and Bioimaging.

    PubMed

    Łukasiewicz, Łukasz G; Deperasińska, Irena; Poronik, Yevgen M; Jun, Yong Woong; Banasiewicz, Marzena; Kozankiewicz, Bolesław; Ahn, Kyo Han; Gryko, Daniel T

    2016-06-01

    Two strongly polarized dipolar chromophores possessing a cyclic tertiary amino group at one terminus of the molecule and a CN group at the opposite terminus were designed and synthesized. Their rigid skeleton contains the rarely studied pyrrolo[2,3-b]quinoxaline ring system. The photophysical properties of these regioisomeric dyes were different owing to differing π conjugation between the CN group and the electron-donor moiety. These dipolar molecules showed very intense emission, strong solvatofluorochromism, and sufficient two-photon brightness for bioimaging. One of these regioisomeric dyes, namely, 11-carbonitrile-2,3,4,5,6,7-hexahydro-1H-3a,8,13,13b-tetraazabenzo[b]cyclohepta[1,2,3-jk]fluorene, was successfully utilized in two-photon imaging of mouse organ tissues and showed distinct tissue morphology with high resolution. PMID:27027726

  15. Synthesis of 1,3,4-thiadiazole, 1,3,4-thiadiazine, 1,3,6-thiadiazepane and quinoxaline derivatives from symmetrical dithiobiureas and thioureidoethylthiourea derivatives.

    PubMed

    Hassan, Alaa A; Mourad, Aboul-Fetouh; El-Shaieb, Kamal M; Abou-Zied, Ashraf H

    2005-01-01

    Reactions of N,N;-disubstituted hydrazinecarbothioamides 8a-c and substituted thioureidoethylthioureas 9a-c with 2,3,5,6-tetrachloro-1,4-benzoquinone (chloranil, 10a) and 2,3,5,6-tetrabromo-1,4-benzoquinone (bromanil, 10b) to form N,N;-disubstituted [1,3,4]thiadiazole-2,5-diamines 11a-c, 6,7-dichloro-3-substituted amino-1H-benzo[1,3,4]- thiadiazine-5,8-diones 12a-c, 2,3,7,8-tetrahalothianthrene-1,4,6,9-tetraones 13a,b, 5,6,8- trihalo-7-oxo-3,7-dihydro-2H-quinoxaline-1-carbothioic acid substituted amides 14a-c, 15a-c and 7-substituted imino-[1,3,6]thiadiazepane-3-thiones 16a-c are reported. Rationales for the observed conversions are presented. PMID:18007352

  16. Organic Photosensitizers Incorporating Rigidified Dithieno[3,2-f:2',3'-h]quinoxaline Segment Tethered with Thiophene Substitutes for Dye-Sensitized Solar Cells.

    PubMed

    Ni, Jen-Shyang; Chiu, Tang-Yao; Kao, Wei-Siang; Chou, Hao-Ju; Su, Chao-Chin; Lin, Jiann T

    2016-09-01

    Metal-free D-π-RS-π-A type sensitizers, consisting of triphenylamine as the electron donor, 2,3-bis(3-(2-ethylhexyl)-5-methylthiophen-2-yl)dithieno[3,2-f:2',3'-h]quinoxaline (DTQT) as the rigidified conjugation spacer (RS), thiophene as the π-spacer, and 2-cyanoacrylic acid as the acceptor/anchor, have broad absorption spectra ranging from 350 to 550 nm and a high molar extinction coefficient up to >46 200 M(-1) cm(-1). Under simulated AM 1.5 G illumination, the dye-sensitized solar cells (DSSCs) fabricated from the dyes exhibited light-to-electricity conversions in the range of 6.78% to 8.27%. The best efficiency is slightly higher than that of N719-based standard DSSC (7.92%). The efficiency can be further boosted to 8.51% by optimizing the concentration of LiI electrolyte. PMID:27523392

  17. Syntheses, structural, theoretical studies and thermal behaviors of two luminous copper(I) halide complexes of dipyrido[3,2-f:2,3-h]-quinoxaline

    NASA Astrophysics Data System (ADS)

    Chen, Aihua; Meng, Suci; Zhang, Jinfang; Zhang, Chi

    2013-10-01

    Two new copper(I) complexes containing PPh3 and Dpq, [Cu(Dpq)(PPh3)X] (X = I (1); Br (2)), {PPh3 = triphenylphosphine, Dpq = dipyrido[3,2-f:2,3-h]-quinoxaline} have been synthesized and characterized by elemental analysis, IR spectroscopy, X-ray single crystal analysis, fluorescent analysis, thermal gravimetric analysis and DFT calculations. Single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are mononuclear with similar structures and display a favorable pairwise π-π stacking. Density functional theory and time-dependent density functional theory calculations at the B3LYP/LanL2DZf+6-31G∗ level were performed on both complexes to rationalize their experimental absorption spectra. In addition, 1 and 2 exhibit intense luminescence in ethanol solution at room temperature.

  18. Phenyl radical thermolysis and rate constants for phenyl + O{sub 2}

    SciTech Connect

    Kumaran, S.S.; Michael, J.V.

    1997-08-01

    The thermal decomposition of C{sub 6}H{sub 5}I has been used to prepare in-situ known initial concentrations of phenyl radicals at high temperatures. These can be degraded by direct decomposition at T > 1350 K giving H + C{sub 6}H{sub 4}. Using H-atom ARAS, rate constants for C{sub 6}H{sub 5} dissociation have been measured. Using the same ARAS technique, constants for C{sub 6}H{sub 5} dissociation have been measured. Using the same ARAS technique, the H- and O-atoms formed from the reaction, C{sub 6}H{sub 5} + O{sub 2}, have both been measured. The rate constant results are discussed along with lower T measurements in terms of RRKM calculations using published ab initio electronic structure determinations of transition states.

  19. Revisiting the photodissociation dynamics of the phenyl radical

    SciTech Connect

    Cole-Filipiak, Neil C.; Shapero, Mark; Negru, Bogdan; Neumark, Daniel M.

    2014-09-14

    We have reinvestigated the photodissociation dynamics of the phenyl radical at 248 nm and 193 nm via photofragment translational spectroscopy under a variety of experimental conditions aimed at reducing the nascent internal energy of the phenyl radical and eliminating signal from contaminants. Under these optimized conditions, slower translational energy (P(E{sub T})) distributions for H-atom loss were seen at both wavelengths than in previously reported work. At 193 nm, the branching ratio for C{sub 2}H{sub 2} loss vs. H-atom loss was found to be 0.2 ± 0.1, a significantly lower value than was obtained previously in our laboratory. The new branching ratio agrees with calculated Rice-Ramsperger-Kassel-Marcus rate constants, suggesting that the photodissociation of the phenyl radical at 193 nm can be treated using statistical models. The effects of experimental conditions on the P(E{sub T}) distributions and product branching ratios are discussed.

  20. A study on the spectroscopy and photophysics of N-phenyl pyrrole and N-phenyl pyrazole

    NASA Astrophysics Data System (ADS)

    Sarkar, Aindrila; Chakravorti, Sankar

    1995-03-01

    Comprehensive spectroscopic and photophysical studies of N-phenyl pyrrole (PPr) and N-phenyl pyrazole (PPz) in different solvents show that a new emission band appears due to aggregation of PPr in water. The presence of β-cyclodextrin (β-CD) in aqueous solution of PPr causes deaggregation but the twisted intramolecular charge transfer emission ceases due to the cavity effect. In PPz, aggregation and TICT emission are absent. Protonation in PPz is restricted to a single site only at very high acid concentration. Both the molecules are planar in the ground state.

  1. 40 CFR 721.9538 - Lithium salt of sulfophenyl azo phenyl azo disulfostilbene (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Lithium salt of sulfophenyl azo phenyl... Significant New Uses for Specific Chemical Substances § 721.9538 Lithium salt of sulfophenyl azo phenyl azo... substance identified generically as lithium salt of sulfophenyl azo phenyl azo disulfostilbene (PMN...

  2. 40 CFR 721.9538 - Lithium salt of sulfophenyl azo phenyl azo disulfostilbene (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Lithium salt of sulfophenyl azo phenyl... Significant New Uses for Specific Chemical Substances § 721.9538 Lithium salt of sulfophenyl azo phenyl azo... substance identified generically as lithium salt of sulfophenyl azo phenyl azo disulfostilbene (PMN...

  3. 40 CFR 721.9538 - Lithium salt of sulfophenyl azo phenyl azo disulfostilbene (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Lithium salt of sulfophenyl azo phenyl... Significant New Uses for Specific Chemical Substances § 721.9538 Lithium salt of sulfophenyl azo phenyl azo... substance identified generically as lithium salt of sulfophenyl azo phenyl azo disulfostilbene (PMN...

  4. 40 CFR 721.9538 - Lithium salt of sulfophenyl azo phenyl azo disulfostilbene (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Lithium salt of sulfophenyl azo phenyl... Significant New Uses for Specific Chemical Substances § 721.9538 Lithium salt of sulfophenyl azo phenyl azo... substance identified generically as lithium salt of sulfophenyl azo phenyl azo disulfostilbene (PMN...

  5. Chemistry of the pyrazolidines. 26. Alkylation of 4-benzyliden-1-phenyl-3,5-dioxopyrazolidines

    SciTech Connect

    Moldarev, B.L.; Aronzon, M.E.; Adanin, V.M.; Zyakun, A.M.

    1986-08-01

    The reaction of 4-benzyliden-1-phenyl-3,5-dioxopyrazolidines with alkyl halides in the presence of sodium alkoxide gave 1-phenyl-2-alkyl-4-benzyliden- and 1-phenyl-2,4-dialkyl-4-(..cap alpha..-alkoxybenzyl)-3,4-dioxopyrazolines. The structures of these compounds were confirmed by UV, IR, and PMR spectroscopy, and by mass-spectrometry.

  6. 40 CFR 721.9538 - Lithium salt of sulfophenyl azo phenyl azo disulfostilbene (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Lithium salt of sulfophenyl azo phenyl... Significant New Uses for Specific Chemical Substances § 721.9538 Lithium salt of sulfophenyl azo phenyl azo... substance identified generically as lithium salt of sulfophenyl azo phenyl azo disulfostilbene (PMN...

  7. Amine-phenyl multi-component gradient stationary phases.

    PubMed

    Dewoolkar, Veeren C; Kannan, Balamurali; Ashraf, Kayesh M; Higgins, Daniel A; Collinson, Maryanne M

    2015-09-01

    Continuous multi-component gradients in amine and phenyl groups were fabricated using controlled rate infusion (CRI). Solutions prepared from either 3-aminopropyltriethoxysilane (APTEOS) or phenyltrimethoxysilane (PTMOS) were infused, in a sequential fashion, at a controlled rate into an empty graduated cylinder housing a vertically aligned thin layer chromatography (TLC) plate. The hydrolyzed precursors reacted with an abundance of silanol (SiOH) groups on the TLC plates, covalently attaching the functionalized silane to its surface. The extent of modification by phenyl and amine was determined by the kinetics of each reaction and the exposure time at each point along the TLC plate. The local concentrations of phenyl and amine were measured using diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy, respectively. The profile of the multi-component gradients strongly depended on the order of infusion, the direction of the gradient and the presence of available surface silanol groups. A slightly higher amount of phenyl can be deposited on the TLC plate by first modifying its surface with amine groups as they serve as a catalyst, enhancing condensation. Separation of water- and fat-soluble vitamins and the control of retention factors were demonstrated on the multi-component gradient TLC plates. Uniformly modified and single-component TLC plates gave different separations compared to the multi-component gradient plates. The retention factors of the individual vitamins depended on the order of surface modification, the spotting end, and whether the multi-component gradients align or oppose each other. PMID:26255112

  8. Synthesis and evaluation of the cytotoxic activity of novel ethyl 4-[4-(4-substitutedpiperidin-1-yl)]benzyl-phenylpyrrolo[1,2-a]quinoxaline-carboxylate derivatives in myeloid and lymphoid leukemia cell lines.

    PubMed

    Desplat, Vanessa; Vincenzi, Marian; Lucas, Romain; Moreau, Stéphane; Savrimoutou, Solène; Pinaud, Noël; Lesbordes, Jordi; Peyrilles, Elodie; Marchivie, Mathieu; Routier, Sylvain; Sonnet, Pascal; Rossi, Filomena; Ronga, Luisa; Guillon, Jean

    2016-05-01

    Leukemia is the most common blood cancer, and its development starts at diverse points, leading to distinct subtypes that respond differently to therapy. This heterogeneity is rarely taken into account in therapies, so it is still essential to look for new specific drugs for leukemia subtypes or even for therapy-resistant cases. Among heterocyclic compounds that attracted a lot of attention because of its wide spread biological activities, the pyrrolo[1,2-a]quinoxaline heterocyclic framework has been identified as interesting scaffolds for antiproliferative activity against various human cancer cell lines. In the present study, novel ethyl 4-[4-(4-substitutedpiperidin-1-yl)]benzyl-phenylpyrrolo[1,2-a]quinoxaline-carboxylate derivatives 1a-l have been designed and synthesized. Their cytotoxicities were evaluated against five different leukemia cell lines, including Jurkat and U266 (lymphoid cell lines), and K562, U937, HL60 (myeloid cell lines), as well as normal human peripheral blood mononuclear cells (PBMNCs). Then, apoptosis study was performed with the more interesting compounds. The new pyrrolo[1,2-a]quinoxaline series showed promising cytotoxic potential against all leukemia cell lines tested, and some compounds showed better results than the reference compound A6730. Some compounds, such as 1a, 1e, 1g and 1h are promising because of their high activity against leukemia and their low activity against normal hematopoietic cells. Structure-activity relationships of these new synthetic compounds 1a-l are here also discussed. PMID:26945110

  9. Copper-catalyzed domino synthesis of 2-imino-1H-imidazol-5(2H)-ones and quinoxalines involving C-C bond cleavage with a 1,3-dicarbonyl unit as a leaving group.

    PubMed

    Yang, Yan; Ni, Fan; Shu, Wen-Ming; Wu, An-Xin

    2014-09-01

    Although 2-imino-1H-imidazol-5(2H)-ones have important biological activities in metabolism, their synthesis has rarely been investigated. Quinoxalines as "privileged scaffolds" in medicinal chemistry have been extensively investigated, but the development of novel and efficient synthetic methods remains very attractive. Herein, we have developed two copper-catalyzed domino reactions for the synthesis of 2-imino-1H-imidazol-5(2H)-ones and quinoxalines involving CC bond-cleavage with a 1,3-dicarbonyl unit as a leaving group. The domino sequence for the synthesis of 2-imino-1H-imidazol-5(2H)-ones includes aza-Michael addition, intramolecular cyclization, CC bond-cleavage, 1,2-rearrangement, and aerobic dehydrogenation reaction, whereas the domino sequence for the synthesis of quinoxalines includes aza-Michael addition, intramolecular cyclization, elimination reaction, and CC bond-cleavage reaction. The two domino reactions have significant advantages including high efficiency, mild reaction conditions, and high tolerance of various functional groups. PMID:25079446

  10. Chemically induced Parkinson's disease: intermediates in the oxidation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine to the 1-methyl-4-phenyl-pyridinium ion

    SciTech Connect

    Chacon, J.N.; Chedekel, M.R.; Land, E.J.; Truscott, T.G.

    1987-04-29

    Various unstable intermediate oxidation states have been postulated in the metabolic activation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine to the 1-methyl-4-phenyl pyridinium ion. We now report the first direct observation of these free radical intermediates by pulse radiolysis and flash photolysis. Studies are described of various reactions of such species, in particular with dopamine whose autoxidation to dopamine quinone is reported to be potentiated by 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine.

  11. Disposition of the Dietary Mutagen 2-Amino-3,8-dimethylimidazo[4,5- f ]quinoxaline in Healthy and Pancreatic Cancer Compromised Humans

    DOE PAGESBeta

    Malfatti, Michael A.; Kuhn, Edward A.; Turteltaub, Kenneth W.; Vickers, Selwyn M.; Jensen, Eric H.; Strayer, Lori; Anderson, Kristin E.

    2016-02-26

    Pancreatic cancer is the fourth leading cause of cancer death in the U.S. Once diagnosed, prognosis is poor with a 5-year survival rate of less than 5%. Exposure to carcinogenic heterocyclic amines (HCAs) derived from cooked meat has been shown to be positively associated with pancreatic cancer risk. To evaluate the processes that determines the carcinogenic potential of HCAs for human pancreas, 14-carbon labeled 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), a putative human carcinogenic HCA found in well-done cooked meat, was administered at a dietary relevant dose to human volunteers diagnosed with pancreatic cancer undergoing partial pancreatectomy and healthy control volunteers. After 14C-MeIQx exposure,more » blood and urine was collected for pharmacokinetic and metabolite analysis. MeIQx-DNA adducts levels were quantified by accelerator mass spectrometry from pancreatic tissue excised during surgery from the cancer patient group. Pharmacokinetic analysis of plasma revealed a rapid distribution of MeIQx with a plasma elimination half-life of approximately 3.5 hr in 50% of the cancer patients and all of the control volunteers. In 2 of the 4 cancer patients very low levels of MeIQx were detected in plasma and urine suggesting low absorption from the gut into the plasma. Urinary metabolite analysis revealed five MeIQx metabolites with 2-amino-3-methylimidazo[4,5-f]quinoxaline-8-carboxylic acid being the most abundant accounting for 25%–50% of the recovered 14-carbon/ml urine. We found there was no discernable difference in metabolite levels between the cancer patient volunteers and the control group. MeIQx-DNA adduct analysis of pancreas and duodenum tissue revealed adduct levels indistinguishable from background levels. Lastly, although other meat-derived HCA mutagens have been shown to bind DNA in pancreatic tissue, indicating that exposure to HCAs from cooked meat cannot be discounted as a risk factor for pancreatic cancer, the results from this

  12. New osmium cluster compounds containing the heterocyclic ligand 2,3-bis-(diphenylphosphino)quinoxaline (dppq): Ligand isomerization and crystal structures of dppq, the isomeric clusters Os3(CO)10(dppq), and HOs3(CO)9[ -2,3-PhP(h1-C6H4)(Ph2P)quinoxaline

    SciTech Connect

    Hunt, Sean W; Yang, Li; Wang, Xiaoping; Richmond, Michael G.

    2011-01-01

    Treatment of the labile cluster 1,2-Os{sub 3}(CO){sub 10}(MeCN){sub 2} (1) with the diphosphine ligand 2,3-bis(diphenylphosphino)quinoxaline (dppq) at room temperature affords 1,2-Os{sub 3}(CO){sub 10}(dppq) (2b) as the kinetic product of ligand substitution in 84% yield. 2b isomerizes to the thermodynamically more stable dppq-chelated cluster 1,1-Os{sub 3}(CO){sub 10}(dppq) (2c) as the sole observable product under CO at temperatures below 358 K. The kinetics for the conversion of 2b {yields} 2c have been investigated by NMR spectroscopy in CDCl{sub 3} over the temperature range 323-353 K, and the reaction was found to exhibit a rate law that is first order in 2b. The calculated activation parameters [{Delta}H{sup {ne}} = 25.4(4) kcal/mol; {Delta}S{sup {ne}} = -3(1) eu] support an intramolecular isomerization scenario, one that involves the migration of phosphine and CO groups about the cluster polyhedron. The disposition of the dppq ligand in the isomeric Os{sub 3}(CO){sub 10}(dppq) clusters has been established by X-ray crystallography and {sup 31}P NMR spectroscopy. Photolysis of 2c at 366 nm leads to CO loss and ortho metalation of one of the aryl groups on the Ph{sub 2}P moiety to furnish the hydride cluster HOs{sub 3}(CO){sub 9}[{mu}-PhP({eta}{sup 1}-C{sub 6}H{sub 4})(Ph{sub 2}P)quinoxaline] (3). The isomerization behavior exhibited by 2b follows that of related diphosphine-substituted Os{sub 3} clusters prepared by us.

  13. Synthesis and herbicidal activity of phenyl-substituted benzoylpyrazoles.

    PubMed

    Siddall, Thomas L; Ouse, David G; Benko, Zoltan L; Garvin, Gail M; Jackson, Johnny L; McQuiston, Jeffrey M; Ricks, Michael J; Thibault, Thomas D; Turner, James A; Vanheertum, John C; Weimer, Monte R

    2002-12-01

    A novel series of substituted 3-phenyl benzoylpyrazoles were prepared and tested as potential grass herbicides. The targeted materials were prepared by three newly developed synthetic routes, which allowed a comprehensive study of the SAR (structure-activity relationships) of this series. The best combination of grass weed activity (Avena fatua L, Setaria viridis (L) Beauv and Alopecurus myosuroides Huds) and wheat selectivity was obtained with an alkoxy group in the 4-position of the phenyl ring. Activity was further enhanced by the presence of tert-butyl on the pyrazole and a methyl group at the C-2 position of the benzoyl moiety. The alkoxy-substituted 3-phenylbenzoylpyrazoles are a novel class of herbicides with potential utility for control of important grass weeds in cereals. PMID:12476990

  14. Direct synthesis and characterization of phenyl-functionalized SBA-15

    NASA Astrophysics Data System (ADS)

    Wang, Xue-mei; Du, Xin-zhen; Li, Chun-lan; Cao, Xu

    2008-04-01

    Phenyl-functionalized SBA-15 materials (Ph-SBA-15) were directly synthesized by using tri-block copolymer Pluronic P123 as templating agent under acidic conditions. The samples were characterized by Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetry analysis (TGA) and N 2 adsorption-desorption. The results show that the phenyl groups are covalently attached to the pore wall of SBA-15 after modification. The functionalized materials still preserve a desirable two-dimensional P6 mm hexagonal structure and have large specific surface area and pore volume although the molar ratio of phenyltrimethoxysilane in total silica precursors is as high as 23.0%.

  15. 2-Phenyl­biguanidinium hydrogen succinate methanol monosolvate

    PubMed Central

    Matulková, Irena; Císařová, Ivana; Němec, Ivan

    2010-01-01

    In the crystal of the title compound, C8H12N5 +·C4H5O4 −·CH3OH, the hydrogen succinate anions form infinite [010] chains via short, almost symmetrical, O⋯H⋯O hydrogen bonds. The 2-phenyl­biguanidium cations inter­connect these chains into layers lying parallel to the bc plane by way of N—H⋯O links. These planes only weakly inter­act in the direction of the a axis via C—H⋯π contacts between offset phenyl rings, leaving as much as 17% of the unit-cell volume accessible for the solvent. However, the methanol solvent mol­ecules could not be resolved due to extensive disorder and their assumed presence was removed from the overall scattering by the PLATON SQUEEZE procedure. PMID:21589482

  16. Electrochemical reduction of phenyl(9-m-carboranyl)iodonium tetrafluoroborate

    SciTech Connect

    Groshin, V.V.; Butin, K.P.; Shcherbina, T.M.; Tolstnaya, T.P.

    1985-08-20

    This paper shows that the controlled-potential electrolysis (-0.4 V, s.c.e.) of phenyl(9-m-carboranyl)iodonium tetrafluoroborate (I) on a mercury cathode in a 0.05 M solution of Bu/sub 4/NBF/sup -//sub 4/ in DMF proceeds regiospecifically with breakage exclusively of the C-I bond in the cation of (I) to give 70% benzene (as indicated in gas-liquid chromatography) and 73% 9-iodo-m-carborane with a current yield of about 80%. These results support a previous hypothesis that all the reactions of phenyl(B-carboranyl)iodonium salts with nucleophiles, which accompany breakage of the C-I bond, proceed by the transfer of one electron from the nucleophile to the iodonium cation.

  17. Multiresidue HPLC methods for phenyl urea herbicides in water.

    PubMed

    Ruberu, S R; Draper, W M; Perera, S K

    2000-09-01

    High-performance liquid chromatography (HPLC) methods for the determination of phenyl urea herbicides in water are described. The target compounds include chlortoluron, diuron, fluometuron, isoproturon, linuron, metobromuron, metoxuron, monuron, neburon, and siduron. Water was subjected to solid phase extraction (SPE) using either automated SPE with 47 mm C(18) Empore disks or on-line precolumn concentration. Herbicides were separated on a C(18) reversed phase column with an acetonitile-water gradient and were detected with either a diode array detector (DAD) or a postcolumn photolysis and derivatization (PPD) detector system. Photolysis converted the phenyl ureas to monoalkylamines that were derivatized to fluorescent isoindoles by reaction with o-phthalaldehyde and 2-mercaptoethanol. The DAD monitoring at 245 nm was linear over three decades with instrument detection limits of approximately 0.01 mg/L. SPE efficiency was between 48 and 70% in laboratory reagent water, but use of the internal standard quantitation method improved accuracy. High total dissolved solids and total organic carbon values in surface water improved recoveries relative to laboratory reagent water for all of the phenyl ureas. In Colorado River water spiked at 1 or 50 microg/L, mean recoveries ranged from 74 to 104%. Method detection limits (MDLs) ranged from 4 to 40 ng/L (parts per trillion) with the DAD instrument. PPD detection was highly specific but resulted in a slight loss in chromatographic efficiency and average MDLs approximately 5 times higher using a single set of detection conditions. The study indicates that methods based on SPE followed by HPLC with diode array or PPD detection have practical utility for trace analysis of phenyl ureas in drinking water or surface waters. PMID:10995323

  18. Proton triggered emission and selective sensing of picric acid by the fluorescent aggregates of 6,7-dimethyl-2,3-bis-(2-pyridyl)-quinoxaline.

    PubMed

    Mazumdar, Prativa; Maity, Samir; Shyamal, Milan; Das, Debasish; Sahoo, Gobinda Prasad; Misra, Ajay

    2016-03-14

    A heteroatom containing organic fluorophore 6,7-dimethyl-2,3-bis-(2-pyridyl)-quinoxaline (BPQ) is weakly emissive in solution but its emission properties are highly enhanced in the aggregated state due to the restriction of intramolecular rotation (RIR) and large amplitude vibrational modes, demonstrating the phenomenon, aggregation induced emission enhancement (AIEE). It has strong proton capture capability, allowing reversible fluorescence switching in basic and acidic medium and the emission color changes from blue to green in the aggregated state through protonation. It has been explained as a competition between intramolecular charge transfers (ICTs) and the AIEE phenomena at a lower pH range (pH ∼1-4). Such behavior enables it as a fluorescent pH sensor for detection in acidic and basic medium. Morphologies of the particles are characterized using optical and field emission scanning electron microscopic (FESEM) studies. The turn off fluorescence properties of aggregated BPQ have been utilized for the selective detection of picric acid and the fluorescence quenching is explained due to ground state complexation with a strong quenching constant, 7.81 × 10(4) M(-1). PMID:26608816

  19. Speciation of selenium in environmental samples by solid-phase spectrophotometry using 2,3-dichloro-6-(2,7-dihydroxy-naphthylazo)quinoxaline.

    PubMed

    Amin, Alaa S

    2014-01-01

    Solid-phase spectrophotometry was applied to determination of trace amounts of selenium (Se) in water, soil, plant materials, human hair, and a cosmetic preparation (lipstick). Se(IV) was sorbed in a dextran type lipophilic gel as a complex with 2,3-dichloro-6-(2,7-dihydroxy-naphthylazo)quinoxaline (DCDHNAQ), whereas Se(VI) was determined after boiling in HCI for 10 min to convert Se(VI) to Se(IV). Resin phase absorbances at 588 and 800 nm were measured directly, which allowed the determination of Se in the range of 0.2-3.3 microg/L with an RSD of 1.22%. The influences of analytical parameters including pH of the aqueous solution, amounts of DCDHNAQ, and sample volume were investigated. The molar absorptivities were found to be 1.09 x 10(6), 4.60 x 10(6), and 1.23 x 10(7) L/mol cm for 100, 500, and 1000 mL, respectively. The LOD and LOQ of the 500 mL sample method were 110 and 360 ng/L, respectively, when using 50 mg dextran type lipophilic gel. For a 1000 mL sample, the LOD and LOQ were 60 and 200 ng/L, respectively, using 50 mg of the exchanger. Increasing the sample volume enhanced the sensitivity. No considerable interferences were observed from other investigated anions and cations on the Se determination. PMID:24830171

  20. Roles of ROS mediated oxidative stress and DNA damage in 3-methyl-2-quinoxalin benzenevinylketo-1, 4-dioxide-induced immunotoxicity of Sprague-Dawley rats.

    PubMed

    Gao, Hui; Wang, Di; Zhang, Shun; Xu, Mengjing; Yang, Wei; Yan, Peipei; Liu, Yang; Luo, Xiao; Wu, Hailei; Yao, Ping; Yan, Hong; Liu, Liegang

    2015-11-01

    3-methyl-2-quinoxalin benzenevinylketo-1, 4-dioxide (Quinocetone, QCT) has been broadly used to treat dysentery and promote animal growth in food producing animals. However, its potential toxicity could not been neglected as parts of safety assessment according to the acceptable guidelines for QCT administration. In this study, the immunotoxicity of QCT was investigated in male Sprague-Dawley (SD) rats following a 28-day oral exposure at doses of 0, 50, 800, and 2400 mg/kg/day. The food consumption, body weight gain and relative spleen weight were significantly decreased by QCT in a dose-dependent manner. Treatment of rats with QCT also notably suppressed the T-cell proliferation and natural killer (NK) cell activity, accompanied by intracellular reactive oxygen species (ROS) accumulation, antioxidant system inhibition and DNA damage enhancement. Thus, the primary finding of this study is that QCT exposure (2400 mg/kg/day) could cause immunotoxicity in SD rats due to ROS mediated oxidative stress and DNA damage. PMID:26361855

  1. Monoclonal antibody production and indirect competitive enzyme-linked immunosorbent assay development of 3-methyl-quinoxaline-2-carboxylic acid based on novel haptens.

    PubMed

    Li, Guopeng; Zhao, Liang; Zhou, Feng; Li, Jiaying; Xing, Yuan; Wang, Tiangang; Zhou, Xilong; Ji, Baoping; Ren, Wanpeng

    2016-10-15

    Two novel immunizing haptens of 3-methyl-quinoxaline-2-carboxylic acid (MQCA) were synthesized and conjugated with cationized bovine serum albumin. Female BALB/c mice were immunized with above conjugates, splenocytes were fused with Sp2/0 cells to produce monoclonal antibody. Compared with previous studies, antibodies raised in this work showed higher sensitivity. Meantime, a novel heterologous coating hapten was also prepared. The indirect competitive enzyme-linked immunosorbent assay (icELISA) based on the optimum condition showed an IC50 of 3.1μg/kg (ppb), and the linear range of 0.46-10.5ppb for MQCA. The limit of detect (LOD) of MQCA in swine muscle, swine liver and chicken was 0.32, 0.54, and 0.28ppb, respectively. The LOD of this assay can satisfy the minimum required performance levels (4ppb) for MQCA. These results indicated that the proposed ELISA, with high sensitivity and specificity, as well as good reproducibility and accuracy, is suitable for determination of MQCA residues in food samples. PMID:27173564

  2. Saturable absorption and two-photon absorption of 1,2,5-thiadiazolo[3,4-g]quinoxaline based derivatives with near-infrared fluorescence

    NASA Astrophysics Data System (ADS)

    Du, Yabing; Lin, Xiaodong; Jia, Tingjian; Dong, Jun

    2015-03-01

    Organic molecules with near-infrared (NIR) fluorescence are extremely interesting for the applications in nonlinear optical devices and bioimaging. However, such kind of materials have been relatively rarely studied. In this work, the nonlinear optical properties of 1,2,5-thiadiazolo[3,4-g]quinoxaline based derivatives with NIR fluorescence emission have been investigated for the first time. Under the excitation of femtosecond pulses at 532 nm, the chromophore with dithienyl as donor (TQ2) presents saturable absorption (SA) behavior, while no SA has been observed in the derivative with biphenyl (TQ1) as donor. Moreover, TQ2 exhibits much larger two-photon absorption (TPA) cross-sections with strong NIR fluorescence in the second biological window. The larger nonlinear optical properties of TQ2 is due to the introduction of stronger electron-donating group (dithienyl) and the resultant enhanced intramolecular charge transfer properties. At the end, TPA based optical limiting behaviors of the molecules are demonstrated in THF solutions, thanks to their large solubility and strong TPA.

  3. Fragrance material review on ethyl phenyl carbinyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of ethyl phenyl carbinyl acetate when used as a fragrance ingredient is presented. Ethyl phenyl carbinyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for ethyl phenyl carbinyl acetate were evaluated, then summarized, and includes: physical properties; acute toxicity; skin irritation; and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22433983

  4. Fragrance material review on 2-phenyl-2-propanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-phenyl-2-propanol when used as a fragrance ingredient is presented. 2-Phenyl-2-propanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-phenyl-2-propanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, skin sensitization, and toxicokinetics data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. PMID:22033099

  5. Fragrance material review on 1-phenyl-3-methyl-3-pentanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 1-phenyl-3-methyl-3-pentanol when used as a fragrance ingredient is presented. 1-Phenyl-3-methyl-3-pentanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 1-phenyl-3-methyl-3-pentanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, and genotoxicity data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. PMID:22033089

  6. Fragrance material review on 2-methyl-4-phenyl-2-butanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-4-phenyl-2-butanol when used as a fragrance ingredient is presented. 2-methyl-4-phenyl-2-butanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-4-phenyl-2-butanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. assessment of aryl alkyl alcohols when used as fragrance ingredients. PMID:22036982

  7. 40 CFR 721.10349 - 1,4-Benzenediamine, N′-(alkyl)-N-[4-[(alkyl)amino]phenyl]-N-phenyl- (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,4-Benzenediamine, Nâ²-(alkyl)-N- phenyl]-N-phenyl- (generic). 721.10349 Section 721.10349 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10349 1,4-Benzenediamine, N′-(alkyl)-N-...

  8. 40 CFR 721.10349 - 1,4-Benzenediamine, N′-(alkyl)-N-[4-[(alkyl)amino]phenyl]-N-phenyl- (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 1,4-Benzenediamine, Nâ²-(alkyl)-N- phenyl]-N-phenyl- (generic). 721.10349 Section 721.10349 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10349 1,4-Benzenediamine, N′-(alkyl)-N-...

  9. 40 CFR 721.10349 - 1,4-Benzenediamine, N′-(alkyl)-N-[4-[(alkyl)amino]phenyl]-N-phenyl- (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,4-Benzenediamine, Nâ²-(alkyl)-N- phenyl]-N-phenyl- (generic). 721.10349 Section 721.10349 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10349 1,4-Benzenediamine, N′-(alkyl)-N-...

  10. Synthesis of 2-(methylsulfonyl)-5-(4-(methylsulfonyl) phenyl)-4-phenyl-1H-[5-(14) C]imidazole, a selective COX-2 inhibitor, via asymmetrical benzoins.

    PubMed

    Shirvani, Gholamhossein; Shockravi, Abbas; Amini, Mohsen; Saemian, Nader

    2016-04-01

    4,5-Diarylimidazoles labeled with carbon-14 in the 5-position of the imidazole ring were prepared as a part of three-step sequence from 2-hydroxy-1-(4-(methylthio)phenyl)-2-phenyl[1-(14) C]ethanone as a key synthetic intermediate which has been synthesized from potassium [(14) C]cyanide. PMID:26916231

  11. Catalytic reaction of 3-phenyl-2-propyn-1-ol with alcohols

    SciTech Connect

    Grigoryan, S.G.; Avetisyan, K.G.; Matnishyan, A.A.

    1987-01-10

    The cyclic ketal 2,5-dimethyl-2,5-bis(3-phenyl-2-propynyloxy)-1,4-dioxane was obtained by the reaction of 3-phenyl-2-propyn-1=ol with propargyl alcohol in the presence of the HgO-BF/sub 3/ O(C/sub 2/H/sub 5/)/sub 2/ catalytic system. The transformation of 3-phenyl-2-propyn-1-ol and its ethers in methanol and ethanol by the action of the above-mentioned catalytic system leads to 1-phenyl-3-alkoxy-1-propanone, 1-phenyl-1,1,3-trialkoxypropane, and 1-phenyl-2-propen-1-one. The intermediate organomercury compound, which is the product from regioselective addition of mercuric oxide and the saturated alcohol at the triple bond, was isolated. Its protodemercuration led to the above-mentioned linear products. The formation of the cyclic ketal is presumably due to the preferred formation of mercury bis-hydroxypropargylide.

  12. Identification of Novel Phenyl Butenonyl C-Glycosides with Ureidyl and Sulfonamidyl Moieties as Antimalarial Agents

    PubMed Central

    2014-01-01

    A new series of C-linked phenyl butenonyl glycosides bearing ureidyl(thioureidyl) and sulfonamidyl moieties in the phenyl rings were designed, synthesized, and evaluated for their in vitro antimalarial activities against Plasmodium falciparum 3D7 (CQ sensitive) and K1 (CQ resistant) strains. Among all the compounds screened the C-linked phenyl butenonyl glycosides bearing sulfonamidyl moiety (5a) and ureidyl moiety in the phenyl ring (7d and 8c) showed promising antimalarial activities against both 3D7 and K1 strains with IC50 values in micromolar range and low cytotoxicity offering new HITS for further exploration. PMID:25147607

  13. Enzymatic synthesis of S-phenyl-L-cysteine from keratin hydrolysis industries wastewater with tryptophan synthase.

    PubMed

    Xu, Lisheng; Wang, Zhiyuan; Mao, Pingting; Liu, Junzhong; Zhang, Hongjuan; Liu, Qian; Jiao, Qing-Cai

    2013-04-01

    An economical method for production of S-phenyl-L-cysteine from keratin acid hydrolysis wastewater (KHW) containing L-serine was developed by recombinant tryptophan synthase. This study provides us with an alternative KHW utilization strategy to synthesize S-phenyl-L-cysteine. Tryptophan synthase could efficiently convert L-serine contained in KHW to S-phenyl-L-cysteine at pH 9.0, 40°C and Trion X-100 of 0.02%. In a scale up study, L-serine conversion rate reach 97.1% with a final S-phenyl-L-cysteine concentration of 38.6 g l(-1). PMID:23478091

  14. The critical role of oxidative stress in the toxicity and metabolism of quinoxaline 1,4-di-N-oxides in vitro and in vivo.

    PubMed

    Wang, Xu; Martínez, María-Aránzazu; Cheng, Guyue; Liu, Zhaoying; Huang, Lingli; Dai, Menghong; Chen, Dongmei; Martínez-Larrañaga, María-Rosa; Anadón, Arturo; Yuan, Zonghui

    2016-05-01

    Quinoxaline 1,4-dioxide derivatives (QdNOs) have been widely used as growth promoters and antibacterial agents. Carbadox (CBX), olaquindox (OLA), quinocetone (QCT), cyadox (CYA) and mequindox (MEQ) are the classical members of QdNOs. Some members of QdNOs are known to cause a variety of toxic effects. To date, however, almost no review has addressed the toxicity and metabolism of QdNOs in relation to oxidative stress. This review focused on the research progress associated with oxidative stress as a plausible mechanism for QdNO-induced toxicity and metabolism. The present review documented that the studies were performed over the past 10 years to interpret the generation of reactive oxygen species (ROS) and oxidative stress as the results of QdNO treatment and have correlated them with various types of QdNO toxicity, suggesting that oxidative stress plays critical roles in their toxicities. The major metabolic pathways of QdNOs are N→O group reduction and hydroxylation. Xanthine oxidoreductase (XOR), aldehyde oxidase (SsAOX1), carbonyl reductase (CBR1) and cytochrome P450 (CYP) enzymes were involved in the QdNOs metabolism. Further understanding the role of oxidative stress in QdNOs-induced toxicity will throw new light onto the use of antioxidants and scavengers of ROS as well as onto the blind spots of metabolism and the metabolizing enzymes of QdNOs. The present review might contribute to revealing the QdNOs toxicity, protecting against oxidative damage and helping to improve the rational use of concurrent drugs, while developing novel QdNO compounds with more efficient potentials and less toxic effects. PMID:27285897

  15. Phase transformation of calcium phenyl phosphate in calcium hydroxyapatite

    SciTech Connect

    Tanaka, Hidekazu . E-mail: hidekazu@riko.shimane-u.ac.jp; Ibaraki, Koshiro; Uemura, Masao; Hino, Ryozi; Kandori, Kazuhiko; Ishikawa, Tatsuo

    2007-07-03

    Calcium phenyl phosphate (CaPP) was synthesized from a mixture of Ca(OH){sub 2} and phenyl phosphate (C{sub 6}H{sub 5}PO{sub 4}H{sub 2}) in an aqueous media. XRD pattern of CaPP exhibited five diffraction peaks at 2{theta} = 6.6, 13.3, 20.0, 26.8 and 33.7{sup o}. The d-spacing ratio of these peaks was ca. 1:1/2:1/3:1/4:1/5. The molar ratios of Ca/P and phenyl/P of CaPP were 1.0 and 0.92, respectively, and the chemical formula of the material was expressed as (C{sub 6}H{sub 5}PO{sub 4}){sub 0.92}(HPO{sub 4}){sub 0.08}Ca.1.3H{sub 2}O, similar to that of dicalcium phosphate dihydrate (CaHPO{sub 4}.2H{sub 2}O: DCPD). These results allowed us to infer that CaPP is composed of a multilayer alternating bilayer of phenyl groups of the phosphates and DCPD-like phase. The structure of the material was essentially not altered after aging at pH 9.0-11.0 and 85 deg. C in an aqueous media. While, after aging at pH {<=}8.0, the diffraction peaks of CaPP were suddenly weakened and disappeared at pH 7.0. Besides, new peaks due to calcium hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}: Hap) appeared and their intensity was strengthened with decreasing the solution pH. TEM observation revealed that the Hap particles formed at pH 6.0 are fibrous with ca. 1.5 {mu}m in length and ca. 0.2 {mu}m in width. From these results, it is presumed that the layered CaPP was dissolved, hydrolyzed and reprecipitated to fibrous Hap particles at pH {<=}8.0 and 85 deg. C in aqueous media. This phase transformation of CaPP in Hap resembled to the formation mechanism of Hap in animal organism.

  16. N,N′-(Oxydi-p-phenyl­ene)diphthalimide

    PubMed Central

    Li, Yi-Tao; Wang, Zhiguo

    2008-01-01

    The title compound, C28H16N2O5, is a bis-imide derivative in which two phthalimide units are linked by an oxydi-p-phenyl­ene bridge. The dihedral angle between the planes of the two central benzene rings is 86.1 (4)°. The isoindole groups make dihedral angles of 46.0 (14) and 77.5 (13)° with the attached benzene rings. Inter­molecular C—H⋯O hydrogen bonds contribute to the stability of the structure. PMID:21200954

  17. 4-Phenyl­diazenyl-2-[(R)-(1-phenyl­ethyl)imino­meth­yl]phenol

    PubMed Central

    Aritake, Yoshikazu; Watanabe, Yoshimasa; Akitsu, Takashiro

    2010-01-01

    The title chiral photochromic Schiff base compound, C21H19N3O, was synthesized from (R)-1-phenyl­ethyl­amine and the salicylaldehyde of an azobenzene derivative. The mol­ecule corresponds to the phenol–imine tautomer, the C=N and N—C bond distances being 1.279 (3) and 1.477 (3) Å, respectively. An intra­molecular O—H⋯N hydrogen bond occurs. The diazenyl group adopts a trans form with an N=N distance of 1.243 (3) Å. PMID:21580594

  18. Thermolysis of surface-immobilized phenethyl phenyl ether

    SciTech Connect

    Britt, P.F.; Buchanan, A.C. III; Hitsman, V.M.

    1991-01-01

    Our research has focused on modeling the constraints on free-radical reactions that might be imposed in coal as a consequence of its cross-linked macromolecular structure by covalently bonding diphenylalkanes to an inert silica surface. A surface-immobilized phenethyl phenyl ether ({approx}PhCH{sub 2}CH{sub 2}POh, or {approx}PPE-3) has been prepared as a model for ether linkages in lignin by the condensation of p-HOPhCH{sub 2}CH{sub 2}OPh with the surface hydroxyls of a high purity fumed silica. Thermolysis of {approx}PPE-3 at saturation surface coverage at 375{degree}C produces {approx}PhCH = CH{sub 2} and PhOH as the major products which are consistent with the proposed free-radical chain mechanism for the decomposition of fluid-phase phenethyl phenyl ether. However, significant quantities of {approx}PhCH{sub 3} and PhCHO (ca. 18% of the products) are produced indicating the emergence of a new reaction pathway on the surface. The mechanism for the decomposition of {approx}PPE-3 will be discussed in light of this new information. 18 refs., 1 fig.

  19. Phenibut (beta-phenyl-GABA): a tranquilizer and nootropic drug.

    PubMed

    Lapin, I

    2001-01-01

    Phenibut (beta-phenyl-gamma-aminobutyric acid HCl) is a neuropsychotropic drug that was discovered and introduced into clinical practice in Russia in the 1960s. It has anxiolytic and nootropic (cognition enhancing) effects. It acts as a GABA-mimetic, primarily at GABA(B) and, to some extent, at GABA(A) receptors. It also stimulates dopamine receptors and antagonizes beta-phenethylamine (PEA), a putative endogenous anxiogenic. The psychopharmacological activity of phenibut is similar to that of baclofen, a p-Cl-derivative of phenibut. This article reviews the structure-activity relationship of phenibut and its derivatives. Emphasis is placed on the importance of the position of the phenyl ring, the role of the carboxyl group, and the activity of optical isomers. Comparison of phenibut with piracetam and diazepam reveals similarities and differences in their pharmacological and clinical effects. Phenibut is widely used in Russia to relieve tension, anxiety, and fear, to improve sleep in psychosomatic or neurotic patients; as well as a pre- or post-operative medication. It is also used in the therapy of disorders characterized by asthenia and depression, as well as in post-traumatic stress, stuttering and vestibular disorders. PMID:11830761

  20. Influence of the ester chain length on the mesogenic behavior and optical anisotropy of 4-[[4-(butoxy)phenyl]diazenyl]phenyl alkanoates

    NASA Astrophysics Data System (ADS)

    Niezgoda, Izabela; Szypszak, Ewelina; Dardas, Dorota; Galewski, Zbigniew

    2016-04-01

    In this manuscript, we report synthesis and physico-chemical characterization of 4-[[4-(butoxy)phenyl]diazenyl]phenyl alkanoates homologous series. For the first time, nineteen derivatives are described here. The enantiotropic nematic phase is typically observed among all members of this series. However, in the case of 4-[[4-(butoxy)phenyl]diazenyl]phenyl stearate, the nematic phase shows a monotropic character. In addition to liquid-crystalline polymorphism, a second crystalline form was observed in some homologs. Furthermore, using a photoelastic modulator, the optical anisotropy in the nematic phase was determined in the first nine compounds of this series. Temperature dependence of optical anisotropy at significantly lower values of reduced temperature is relatively weak. In contrast, optical anisotropy shows a strong temperature effect near isotropization. Moreover, the influence of the ester chain elongation on liquid crystalline and optical properties was established.

  1. Asymmetric ligand-exchange reaction of biphenol derivatives and chiral bis(oxazolinyl)phenyl-rhodium complex.

    PubMed

    Inoue, Hiroko; Ito, Jun-ichi; Kikuchi, Makoto; Nishiyama, Hisao

    2008-09-01

    Chiral bis(oxazolinyl)phenyl-rhodium acetate complex can enantioselectively capture 1,1'-binaphthol derivatives by ligand-exchange reaction. The structure of the bis(oxazolinyl)phenyl-rhodium biphenol and binaphthol complexes were confirmed by X-ray analysis. PMID:18496824

  2. Crystal structure of an RNA duplex containing phenyl-ribonucleotides, hydrophobic isosteres of the natural pyrimidines.

    PubMed Central

    Minasov, G; Matulic-Adamic, J; Wilds, C J; Haeberli, P; Usman, N; Beigelman, L; Egli, M

    2000-01-01

    Chemically modified nucleotide analogs have gained widespread popularity for probing structure-function relationships. Among the modifications that were incorporated into RNAs for assessing the role of individual functional groups, the phenyl nucleotide has displayed surprising effects both in the contexts of the hammerhead ribozyme and pre-mRNA splicing. To examine the conformational properties of this hydrophobic base analog, we determined the crystal structure of an RNA double helix with incorporated phenyl ribonucleotides at 1.97 A resolution. In the structure, phenyl residues are engaged in self-pairing and their arrangements suggest energetically favorable stacking interactions with 3'-adjacent guanines. The presence of the phenyl rings in the center of the duplex results in only moderate changes of the helical geometry. This finding is in line with those of earlier experiments that showed the phenyl analog to be a remarkably good mimetic of natural base function. Because the stacking interactions displayed by phenyl residues appear to be similar to those for natural bases, reduced conformational restriction due to the lack of hydrogen bonds with phenyl as well as alterations in its solvent structure may be the main causes of the activity changes with phenyl-modified RNAs. PMID:11105752

  3. 40 CFR 721.275 - Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Halogenated-N-(2-propenyl)-N... New Uses for Specific Chemical Substances § 721.275 Halogenated-N-(2-propenyl)-N-(substituted phenyl... identified generically as halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide (P-83-1085) is...

  4. 40 CFR 721.275 - Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Halogenated-N-(2-propenyl)-N... New Uses for Specific Chemical Substances § 721.275 Halogenated-N-(2-propenyl)-N-(substituted phenyl... identified generically as halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide (P-83-1085) is...

  5. 40 CFR 721.275 - Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Halogenated-N-(2-propenyl)-N... New Uses for Specific Chemical Substances § 721.275 Halogenated-N-(2-propenyl)-N-(substituted phenyl... identified generically as halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide (P-83-1085) is...

  6. Evaluation of phenyl carbonates as electrolyte additives in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Petibon, R.; Rotermund, L. M.; Dahn, J. R.

    2015-08-01

    The impact of the electrolyte additives methyl phenyl carbonate, ethyl phenyl carbonate, and diphenyl carbonate was evaluated in Li[Ni0.33Mn0.33Co0.33]O2/graphite pouch cells with or without 2% vinylene carbonate. Experiments included high precision coulometry, automated storage, electrochemical impedance spectroscopy on symmetric cells and gas chromatography coupled with mass spectrometry. Gas chromatography/mass spectrometry analysis, electrochemical studies during the first charge and impedance spectroscopy on symmetric cells indicated that phenyl carbonates act as solid electrolyte interphase modifiers rather than formers. High precision coulometry showed that cells containing 1-4 wt% methyl phenyl carbonate, ethyl phenyl carbonate or diphenyl carbonate had similar coulombic efficiencies and charge-endpoint capacity slippage as cells filled with 2 wt% vinylene carbonate. Impedance spectroscopy showed that cells containing phenyl carbonates have substantially lower impedance than cells filled with 2 wt% vinylene carbonate and produced minimal volumes of gas during cell use. Results presented in the report show that phenyl carbonates are competitive additives for 4.2 V class cells and should lead to good cycle life, low polarization and low gas evolution during normal use. Phenyl carbonates can also be used as gas-producing safety agents (to trip pressure activated disconnects) in combination with vinylene carbonate in cylindrical or prismatic cells without adverse effects.

  7. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  8. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  9. 40 CFR 721.4840 - Substituted tri-phenyl-meth-ane.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted tri-phenyl-meth-ane. 721.4840 Section 721.4840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... Substances § 721.4840 Substituted tri-phenyl-meth-ane. (a) Chemical substance and significant new...

  10. 40 CFR 721.4840 - Substituted tri-phenyl-meth-ane.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted tri-phenyl-meth-ane. 721.4840 Section 721.4840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... Substances § 721.4840 Substituted tri-phenyl-meth-ane. (a) Chemical substance and significant new...

  11. 40 CFR 721.4840 - Substituted tri-phenyl-meth-ane.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted tri-phenyl-meth-ane. 721.4840 Section 721.4840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... Substances § 721.4840 Substituted tri-phenyl-meth-ane. (a) Chemical substance and significant new...

  12. 40 CFR 721.4840 - Substituted tri-phenyl-meth-ane.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted tri-phenyl-meth-ane. 721.4840 Section 721.4840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... Substances § 721.4840 Substituted tri-phenyl-meth-ane. (a) Chemical substance and significant new...

  13. Ideal gas thermodynamic properties for the phenyl, phenoxy, and o-biphenyl radicals

    NASA Technical Reports Server (NTRS)

    Burcat, A.; Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    Ideal gas thermodynamic properties of the phenyl and o-biphenyl radicals, their deuterated analogs and the phenoxy radical were calculated to 5000 K using estimated vibrational frequencies and structures. The ideal gas thermodynamic properties of benzene, biphenyl, their deuterated analogs and phenyl were also calculated.

  14. 40 CFR 721.4840 - Substituted tri-phenyl-meth-ane.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted tri-phenyl-meth-ane. 721.4840 Section 721.4840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... Substances § 721.4840 Substituted tri-phenyl-meth-ane. (a) Chemical substance and significant new...

  15. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  16. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  17. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  18. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  19. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  20. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  1. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  2. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  3. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Carbon black, 4- substituted] phenyl... Significant New Uses for Specific Chemical Substances § 721.10075 Carbon black, 4- substituted] phenyl...) The chemical substance identified generically as carbon black, 4- substituted] phenyl-modified,...

  4. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Carbon black, 4- substituted] phenyl... Significant New Uses for Specific Chemical Substances § 721.10075 Carbon black, 4- substituted] phenyl...) The chemical substance identified generically as carbon black, 4- substituted] phenyl-modified,...

  5. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Carbon black, 4- substituted] phenyl... Significant New Uses for Specific Chemical Substances § 721.10075 Carbon black, 4- substituted] phenyl...) The chemical substance identified generically as carbon black, 4- substituted] phenyl-modified,...

  6. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Carbon black, 4- substituted] phenyl... Significant New Uses for Specific Chemical Substances § 721.10075 Carbon black, 4- substituted] phenyl...) The chemical substance identified generically as carbon black, 4- substituted] phenyl-modified,...

  7. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Carbon black, 4- substituted] phenyl... Significant New Uses for Specific Chemical Substances § 721.10075 Carbon black, 4- substituted] phenyl...) The chemical substance identified generically as carbon black, 4- substituted] phenyl-modified,...

  8. 40 CFR 721.984 - Amino-hydroxy sulfonaphthylazo-disubstituted phenyl azo benzene carboxylate salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-disubstituted phenyl azo benzene carboxylate salt (generic). 721.984 Section 721.984 Protection of Environment...-disubstituted phenyl azo benzene carboxylate salt (generic). (a) Chemical substance and significant new uses...-disubstituted phenyl azo benzene carboxylate salt (PMN P-00-0351) is subject to reporting under this section...

  9. 40 CFR 721.984 - Amino-hydroxy sulfonaphthylazo-disubstituted phenyl azo benzene carboxylate salt (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-disubstituted phenyl azo benzene carboxylate salt (generic). 721.984 Section 721.984 Protection of Environment...-disubstituted phenyl azo benzene carboxylate salt (generic). (a) Chemical substance and significant new uses...-disubstituted phenyl azo benzene carboxylate salt (PMN P-00-0351) is subject to reporting under this section...

  10. 40 CFR 721.984 - Amino-hydroxy sulfonaphthylazo-disubstituted phenyl azo benzene carboxylate salt (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-disubstituted phenyl azo benzene carboxylate salt (generic). 721.984 Section 721.984 Protection of Environment...-disubstituted phenyl azo benzene carboxylate salt (generic). (a) Chemical substance and significant new uses...-disubstituted phenyl azo benzene carboxylate salt (PMN P-00-0351) is subject to reporting under this section...

  11. 40 CFR 721.984 - Amino-hydroxy sulfonaphthylazo-disubstituted phenyl azo benzene carboxylate salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-disubstituted phenyl azo benzene carboxylate salt (generic). 721.984 Section 721.984 Protection of Environment...-disubstituted phenyl azo benzene carboxylate salt (generic). (a) Chemical substance and significant new uses...-disubstituted phenyl azo benzene carboxylate salt (PMN P-00-0351) is subject to reporting under this section...

  12. 40 CFR 721.984 - Amino-hydroxy sulfonaphthylazo-disubstituted phenyl azo benzene carboxylate salt (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-disubstituted phenyl azo benzene carboxylate salt (generic). 721.984 Section 721.984 Protection of Environment...-disubstituted phenyl azo benzene carboxylate salt (generic). (a) Chemical substance and significant new uses...-disubstituted phenyl azo benzene carboxylate salt (PMN P-00-0351) is subject to reporting under this section...

  13. Discovery of 4-phenyl-2-phenylaminopyridine based TNIK inhibitors.

    PubMed

    Ho, Koc-Kan; Parnell, K Mark; Yuan, Yi; Xu, Yong; Kultgen, Steven G; Hamblin, Steven; Hendrickson, Thomas F; Luo, Bai; Foulks, Jason M; McCullar, Michael V; Kanner, Steven B

    2013-01-15

    A series of compounds based on a 4-phenyl-2-phenylaminopyridine scaffold that are potent and selective inhibitors of Traf2- and Nck-interacting kinase (TNIK) activity are described. These compounds were used as tools to test the importance of TNIK kinase activity in signaling and proliferation in Wnt-activated colorectal cancer cells. The results indicate that pharmacological inhibition of TNIK kinase activity has minimal effects on either Wnt/TCF4/β-catenin-driven transcription or viability. The findings suggest that the kinase activity of TNIK may be less important to Wnt signaling than other aspects of TNIK function, such as its putative role in stabilizing the TCF4/β-catenin transcriptional complex. PMID:23232060

  14. Reaction of dichlorocarbene with 2-phenyl-1,3-oxathiolane

    SciTech Connect

    Nazarov, D.V.; Safiev, O.G.; Zorin, V.V.; Rakhmankulov, D.L.

    1987-10-20

    It was established that the reaction of 2-phenyl-1,3-oxathiolane (I) with dichlorocarbene, generated from chloroform in 50% aqueous solution of sodium hydroxide with the use of triethylbenzylammonium chloride as phase-transfer catalyst, leads to the formation of dichloromethyl thiobenzoate (II) and ethylene with yields of 24 and 38% respectively and 60% conversion in the substrate (I). The reaction was conducted at 35-40/sup 0/C for 24 h with the following amounts of the reagents; 0.5 mole of the substrate (I); 5 moles of chloroform; 600 mol of 50% aqueous sodium hydroxide solution; 1 g of triethylbenzylammonium chloride. Compound (II) was isolated by column liquid chromatography on aluminum oxide (40-250 ..mu..) with a 1:5 mixture of diethyl ether and hexane as eluant. The product was identified by means of the IR, PMR, and /sup 13/C NMR spectra.

  15. O-Propyl N-phenyl­thio­carbamate

    PubMed Central

    Sudkaow, Panyapon; Yeo, Chien Ing; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    Two independent mol­ecules comprise the asymmetric unit in the title thio­carbamide derivative, C10H13NOS. These differ in the relative orientations of terminal ethyl groups [C—C—C—O torsion angles = −66.95 (13) and 55.92 (13)°, respectively]. The phenyl ring is twisted out of the plane of the central residue [Cq—N—Cph—Cph = −146.20 (12) and −144.15 (12)°, respectively; q = quaternary and ph = phen­yl]. The independent mol­ecules are linked into a dimeric aggregate by N—H⋯S hydrogen bonds and an eight-membered thio­amide {⋯H—N—C=S}2 synthon. PMID:22719552

  16. Aging studies on thin tetra-phenyl butadiene films

    NASA Astrophysics Data System (ADS)

    Acciarri, R.; Canci, N.; Cavanna, F.; Segreto, E.; Szelc, A. M.

    2013-10-01

    Tetra-Phenyl Butadiene (TPB) is the most commonly used compound to wave-shift the 128 nm scintillation light of liquid Argon down to the visible spectrum. We present a study on the loss of conversion efficiency of thin TPB films evaporated on reflective foils when exposed to light and atmosphere. The efficiency of the films is measured and monitored with a dedicated set-up that uses gaseous Argon excited by alpha particles to produce 128 nm photons and working at room temperature. In particular we performed a two years long exposure of the samples to lab diffuse light and atmosphere. We also performed more controlled aging tests to investigate the effect of storing samples in a inert atmosphere.

  17. Design and synthesis of some new 1-phenyl-3/4-[4-(aryl/heteroaryl/alkyl-piperazine1-yl)-phenyl-ureas as potent anticonvulsant and antidepressant agents.

    PubMed

    Mishra, Chandra Bhushan; Kumari, Shikha; Tiwari, Manisha

    2016-05-01

    A series of 1-phenyl-3/4-[4-(aryl/heteroaryl/alkyl-piperazine1-yl)-phenyl-urea derivatives (29-42) were designed, synthesized and evaluated for their anticonvulsant activity by using maximal electroshock (MES), subcutaneous pentylenetetrazole (scPTZ) seizure tests. The acute neurotoxicity was checked by rotarod assay. Most of the test compounds were found effective in both seizure tests. Compound 30 (1-{4-[4-(4-chloro-phenyl)-piperazin-1-yl]-phenyl}-3-phenyl-urea) exhibited marked anticonvulsant activity in MES as well as scPTZ tests. The phase II anticonvulsant quantification study of compound 30 indicates the ED50 value of 28.5 mg/kg against MES induced seizures. In addition, this compound also showed considerable protection against pilocarpine induced status epilepticus in rats. Seizures induced by 3-mercaptopropionic acid model and thiosemicarbazide were significantly attenuated by compound 30, which suggested its broad spectrum of anticonvulsant activity. Interestingly, compound 30 displayed better antidepressant activity than standard drug fluoxetine. Moreover, compound 30 appeared as a non-toxic chemical entity in sub-acute toxicity studies. PMID:26891908

  18. Synthesis, Fourier transform infrared and Raman spectra, assignments and analysis of N-(phenyl)- and N-(chloro substituted phenyl)-2,2-dichloroacetamides.

    PubMed

    Arjunan, V; Mohan, S; Subramanian, S; Thimme Gowda, B

    2004-04-01

    N-(phenyl)-2,2-dichloroacetamide (NPA) and N-(chloro substituted phenyl)-2,2-dichloroacetamides of the configuration XyC6H(5-y)-NHCO-CHCl2 (where, X = Cl and y = 1, 2 and 3) were synthesised and the Fourier transform infrared (FTIR) and Fourier transform Raman (FT-Raman) spectra of the compounds were recorded and analysed. The FTIR spectra of all the compounds were recorded in a Bruker IFS 66V spectrometer in the range of 4000-400 cm(-1) and the FT-Raman spectra were also recorded in the same instrument in the region 3500-100 cm(-1). The variation of an amide bond (-NHCO-) parameters with the substitution of the chlorine atom in the phenyl group and the mixing of different normal modes are discussed with the help of potential energy distribution (PED) calculated through normal co-ordinate analysis. PMID:15084334

  19. Ultrafast Dynamics of Polythiophene with Phenyl Vinylene Branches Studied by Femtosecond Fluorescence Spectroscopy in Solution

    NASA Astrophysics Data System (ADS)

    Chu, Sai-Sai; Gao, Chao; Wang, Shu-Feng; Gong, Qi-Huang

    2011-11-01

    Two polythiophene based polymers, poly[(3-[2-[4-(2-ethyl-hexyloxy)-phenyl]-vinyl]-thiophene)-co-thiophene] (PT1) and poly(3-[2-[4-(2-ethyl-hexyloxy)-phenyl]-vinyl]-thiophene) (PT2), are synthesized and investigated by static, picosecond fluorescence spectroscopies and the femtosecond up-conversion technique in solution. Compared with pristine poly(3-hexylthiophene) (P3HT), PT1 and PT2, in which the main chains are decorated with phenyl vinylene present a ‘camel back’ structure in the absorption spectra. Phenyl vinylene side chains induce a new process of charge transfer, chain twisting motion and defect-induced fluorescence quenching at time scales of 1 ps, 10 ps and 150 ps, respectively.

  20. Synthesis of 1-phenyl-2-(phenylcarbamoyl)pyrazolidines as potential anticonvulsant agents.

    PubMed

    Kornet, M J; Garrett, R J

    1979-03-01

    Twelve 1-phenyl-2-(phenylcarbamoyl)pyrazolidines were synthesized from 1-arylpyrazolidines and aryl isocyanates. These adducts showed little anticonvulsant activity in the maximal electroshock seizure and pentylenetetrazol seizure assays. PMID:423135

  1. Phenyl Acetate Preparation from Phenol and Acetic Acid: Reassessment of a Common Textbook Misconception.

    ERIC Educational Resources Information Center

    Hocking, M. B.

    1980-01-01

    Reassesses a common textbook misconception that "...phenols cannot be esterified directly." Results of experiments are discussed and data tables provided of an effective method for the direct preparation of phenyl acetate. (CS)

  2. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOEpatents

    Farha, Omar K; Hupp, Joseph T

    2013-06-25

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  3. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOEpatents

    Farha, Omar K.; Hupp, Joseph T.

    2012-09-11

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  4. Experimental and theoretical investigation of the self-reaction of phenyl radicals.

    SciTech Connect

    Tranter, R. S.; Klippenstein, S. J.; Harding, L. B.; Giri, B. R.; Yang, X.; Kiefer, J. H.; Chemical Sciences and Engineering Division; Univ. of Illinois at Chicago

    2010-08-19

    A combination of experiment and theory is applied to the self-reaction kinetics of phenyl radicals. The dissociation of phenyl iodide is observed with both time-of-flight mass spectrometry, TOF-MS, and laser schlieren, LS, diagnostics coupled to a diaphragmless shock tube for temperatures ranging from 1276 to 1853 K. The LS experiments were performed at pressures of 22 {+-} 2, 54 {+-} 7, and 122 {+-} 6 Torr, and the TOF-MS experiments were performed at pressures in the range 500-700 Torr. These observations are sensitive to both the dissociation of phenyl iodide and to the subsequent self-reaction of the phenyl radicals. The experimental observations indicate that both these reactions are more complicated than previously assumed. The phenyl iodide dissociation yields {approx}6% C{sub 6}H{sub 4} + HI in addition to the major and commonly assumed C{sub 6}H{sub 5} + I channel. The self-reaction of phenyl radicals does not proceed solely by recombination, but also through disproportionation to benzene + o-/m-/p-benzynes, with comparable rate coefficients for both. The various channels in the self-reaction of phenyl radicals are studied with ab initio transition state theory based master equation calculations. These calculations elucidate the complex nature of the C{sub 6}H{sub 5} self-reaction and are consistent with the experimental observations. The theoretical predictions are used as a guide in the development of a model for the phenyl iodide pyrolysis that accurately reproduces the observed laser schlieren profiles over the full range of the observations.

  5. Phenyl shifts in substituted arenes via ipso arenium ions.

    PubMed

    Ajaz, Aida; McLaughlin, Erin C; Skraba, Sarah L; Thamatam, Rajesh; Johnson, Richard P

    2012-11-01

    The isomerization of substituted arenes through ipso arenium ions is an important and general molecular rearrangement that leads to interconversions of constitutional isomers. We show here that the superacid trifluoromethanesulfonic acid (TfOH), ca. 1 M in dichloroethane (DCE), provides reliable catalytic reaction conditions for these rearrangements, easily applied at ambient temperature, reflux (84 °C), or in a microwave reactor for higher temperatures. Interconversion of terphenyl isomers in TfOH/DCE at 84 °C gives an ortho/meta/para equilibrium ratio of 0:65:35, nearly identical to values reported earlier by Olah with catalysis by AlCl(3). For the three triphenylbenzenes, TfOH-catalyzed equilibration strongly (>95%) favors the 1,3,5-triphenyl isomer. Equilibration of the three possible tetraphenylbenzenes gives a 61:39 mixture of the 1,2,3,5- and 1,2,4,5-substituted isomers. Under the reaction conditions explored, none of these structures undergoes significant Scholl cyclization. DFT calculations with inclusion of solvation support a mechanistic scheme in which all of the phenyl migrations occur among a series of ipso arenium ions. In every case studied, the preferred isomers at equilibrium are those that yield highly stable cations by the most exothermic, hence least reversible 1,2-H shift. PMID:23061916

  6. O-phenyl carbamate and phenyl urea thiiranes as selective matrix metalloproteinase-2 inhibitors that cross the blood-brain barrier.

    PubMed

    Gooyit, Major; Song, Wei; Mahasenan, Kiran V; Lichtenwalter, Katerina; Suckow, Mark A; Schroeder, Valerie A; Wolter, William R; Mobashery, Shahriar; Chang, Mayland

    2013-10-24

    Brain metastasis occurs in 20-40% of cancer patients. Treatment is mostly palliative, and the inability of most drugs to penetrate the brain presents one of the greatest challenges in the development of therapeutics for brain metastasis. Matrix metalloproteinase-2 (MMP-2) plays important roles in invasion and vascularization of the central nervous system and represents a potential target for treatment of brain metastasis. Carbonate, O-phenyl carbamate, urea, and N-phenyl carbamate derivatives of SB-3CT, a selective and potent gelatinase inhibitor, were synthesized and evaluated. The O-phenyl carbamate and urea variants were selective and potent inhibitors of MMP-2. Carbamate 5b was metabolized to the potent gelatinase inhibitor 2, which was present at therapeutic concentrations in the brain. In contrast, phenyl urea 6b crossed the blood-brain barrier, however, higher doses would result in therapeutic brain concentrations. Carbamate 5b and urea 6b show potential for intervention of MMP-2-dependent diseases such as brain metastasis. PMID:24028490

  7. O-Phenyl Carbamate and Phenyl Urea Thiiranes as Selective Matrix Metalloproteinase-2 Inhibitors that Cross the Blood-Brain Barrier

    PubMed Central

    Gooyit, Major; Song, Wei; Mahasenan, Kiran V.; Lichtenwalter, Katerina; Suckow, Mark A.; Schroeder, Valerie A.; Wolter, William R.; Mobashery, Shahriar; Chang, Mayland

    2013-01-01

    Brain metastasis occurs in 20% to 40% of cancer patients. Treatment is mostly palliative and the inability of most drugs to penetrate the brain presents one of the greatest challenges in the development of therapeutics for brain metastasis. Matrix metalloproteinase-2 (MMP-2) plays important roles in invasion and vascularization of the central nervous system and represents a potential target for treatment of brain metastasis. Carbonate, O-phenyl carbamate, urea, and N-phenyl carbamate derivatives of SB-3CT, a selective and potent gelatinase inhibitor were synthesized and evaluated. The O-phenyl carbamate and urea variants were selective and potent inhibitors of MMP-2. Carbamate 5b was metabolized to the potent gelatinase inhibitor 2, which was present at therapeutic concentrations in the brain. In contrast, phenyl urea 6b crossed the blood-brain barrier, however higher doses would result in therapeutic brain concentrations. Carbamate 5b and urea 6b show potential for intervention of MMP-2-dependent diseases, such as brain metastasis. PMID:24028490

  8. Crystal structure of 1′,1′′-dimethyl-4′-(4-cholorophen­yl)di­spiro­[11H-indeno[1,2-b]quinoxaline-11,2′-pyrrolidine-3′,3′′-piperidin]-4′′-one

    PubMed Central

    Nagalakshmi, R.A.; Suresh, J.; Malathi, K.; Kumar, R. Ranjith; Lakshman, P. L. Nilantha

    2015-01-01

    In the title compound, C30H27ClN4O, the central pyrrolidine ring adopts an envelope conformation with the methyl­ene C atom being the flap. The quinoxaline and indane rings are each essentially planar, with r.m.s. deviations of 0.027 (1) and 0.0417 (1) Å, respectively. The pyrrolidine ring forms dihedral angles of 88.25 (1) and 83.76 (1)° with the quinoxaline and indane rings, respectively. A weak intra­molecular C—H⋯N inter­action is observed. In the crystal, C—H⋯π inter­actions lead to supra­molecular chains along [101] that assemble in the ac plane. Connections along the b axis are of the type Cl⋯Cl [3.6538 (16) Å]. PMID:25878875

  9. 3-Acetyl-1-(3-methyl­phen­yl)-5-phenyl-1H-pyrazole-4-carbonitrile

    PubMed Central

    Abdel-Aziz, Hatem A.; Al-Obaid, Abdul-Rahman M.; Ghabbour, Hazem A.; Hemamalini, Madhukar; Fun, Hoong-Kun

    2012-01-01

    In the title compound, C19H15N3O, the central pyrazole ring makes dihedral angles of 35.52 (12) and 62.21 (11)° with the attached phenyl and methyl-substituted phenyl rings, respectively. The corresponding angle between the phenyl and methyl-substituted phenyl rings is 62.90 (11)°. In the crystal, mol­ecules are connected by weak C—H⋯O hydrogen bonds, forming supra­molecular chains propagating along the a-axis direction. PMID:22347089

  10. Role of carbon-carbon phenyl migration in the pyrolysis mechanism of β-O-4 lignin model compounds: phenethyl phenyl ether and α-hydroxy phenethyl phenyl ether.

    PubMed

    Beste, Ariana; Buchanan, A C

    2012-12-20

    We investigate phenyl shift and subsequent β-scission reactions for PhCHXCH·OPh [X = H, OH], which are part of the pyrolysis mechanism of phenethyl phenyl ether (PPE) and α-hydroxy PPE. PPE and its derivatives are model compounds for the most common linkage in lignin, the β-O-4 linkage. We use density functional theory to locate transition states and equilibrium structures and kinetic Monte Carlo in combination with transition-state theory for kinetic simulations. Oxygen-carbon and carbon-carbon phenyl shift reactions proceed through cyclic intermediates with similar barriers. However, while subsequent β-scission of the oxygen-carbon shift products proceeds with virtually no barrier, the activation energy for β-scission of the carbon-carbon shift products exceeds 15 kcal/mol. We found that about 15% of β-radical conversion can be attributed to carbon-carbon shift for PPE and α-hydroxy PPE at 618 K. Whereas the oxygen-carbon shift reaction has been established as an integral part of the pyrolysis mechanism of PPE and its derivatives, participation of the carbon-carbon shift reaction has not been shown previously. PMID:23194314

  11. The role of carbon-carbon phenyl migration in the pyrolysis mechanism of beta-O-4 lignin model compounds: phenethyl phenyl ether and alpha-hydroxy phenethyl phenyl ether

    SciTech Connect

    Beste, Ariana; Buchanan III, A C

    2012-01-01

    We investigate phenyl shift and subsequent beta-scission reactions for PhCHXCHOPh [X = H, OH], which are part of the pyrolysis mechanism of phenethyl phenyl ether (PPE) and alpha-hydroxy PPE. PPE and its derivatives are model compounds for the most common linkage in lignin, the beta-O-4 linkage. We use density functional theory to locate transition states and equilibrium structures, and kinetic Monte Carlo in combination with transition state theory for kinetic simulations. Oxygen-carbon and carbon-carbon phenyl shift reactions proceed through cyclic intermediates with similar barriers. But, while subsequent beta-scission of the oxygen-carbon shift products proceeds with virtually no barrier, the activation energy for beta-scission of the carbon-carbon shift products exceeds 15 kcal/mol. We found that about 15 % of beta-radical conversion can be attributed to carbon-carbon shift for PPE and alpha-hydroxy PPE at 618 K. Whereas the oxygen-carbon shift reaction has been established as an integral part of the pyrolysis mechanism of PPE and its derivatives, participation of the carbon-carbon shift reaction has not been shown previously.

  12. Synthesis, spectroscopy, and quantum-chemical calculations on 1-substituted phenyl-3,5-diphenylformazans.

    PubMed

    Tezcan, Habibe; Tokay, Nesrin

    2010-01-01

    In this study 1-substituted phenyl-3,5-diphenylformazans were synthesized from benzaldehyde-N-phenylhydrazone and appropriate phenyldiazonium salts having CH(3), Br, and Cl at the o-, m-, and p-positions of 1-phenyl ring. Their structures were determined by infrared and ultraviolet-visible spectra. Bathochromic effect in accordance with the electron-donating effect of CH(3), Br, and Cl group and its magnitude were dependent upon type and position of substituent on the ring. The ground-state geometries and absorption wavelengths for 1-phenyl substituted formazans were studied with density functional theory and time-dependent density functional theory. The calculations were carried out by using PBE1PBE functional with 6-311G(2d,2p) basis set for lambda(max) of the UV-vis spectra for the studied formazans. A good agreement was obtained between the experimental and computed values. PMID:19910246

  13. Optical Poling of Phenyl-Silica Hybrid Thin Films Doped with Azo-Dye Chromophore

    NASA Astrophysics Data System (ADS)

    Kitaoka, Kenji; Matsuoka, Nobuaki; Si, Jinhai; Mitsuyu, Tsuneo; Hirao, Kazuyuki

    1999-09-01

    Azo-dye doped phenly group substituted silica films were prepared by a sol-gel method from a solution of triethoxyphenlysilane (TEPh), tetraethoxysilane (TEOS) and 4-[N-ethyl-N-(2-hydroxyethyl)]amino-4‧-nitro-azobenzene (DR1). The films were optically poled by the coherent superposition of 1064 nm and 532 nm beams from a Q-switched Nd:YAG laser. Second-order susceptibility χeff of a DR1 doped phenyl group substituted film induced by the optical poling was approximately four times as large as that of the phenyl-free film. The phenyl group in the silica matrix was found to be effective for increasing the second-order nonlinearity and increasing the thermal stability.

  14. Bifunctional phenyl monophosphonic/sulfonic acid ion exchange resin and process for using the same

    DOEpatents

    Alexandratos, Spiro; Shelley, Christopher A.; Horwitz, E. Philip; Chiarizia, Renato; Gula, Michael J.; Xue, Sui; Harvey, James T.

    2002-01-01

    A cross-linked water-insoluble ion exchange resin comprised of polymerized monomers having a phenyl ring is disclosed. A contemplated resin contains (i) polymerized phenyl ring-containing monomers having a phosphonic acid ligand linked to the phenyl ring, (ii) about 2 to about 5 millimoles per gram (mmol/g) of phosphorus as phosphonic acid ligands, and (iii) a sufficient amount of a sulfonic acid ligand such that the ratio of mmol/g of phosphonic acid to mmol/g sulfonic acid is up to 3:1. A process for removing polyvalent metal cations from aqueous solution, and a process for removing iron(III) cations from acidic copper(II) cation-containing solutions that utilize the contemplated resin or other resins are disclosed.

  15. Bifunctional phenyl monophosphonic/sulfonic acid ion exchange resin and process for using the same

    DOEpatents

    Alexandratos, Spiro; Shelley, Christopher A.; Horwitz, E. Philip; Chiarizia, Renato

    2001-01-01

    A cross-linked water-insoluble ion exchange resin comprised of polymerized monomers having a phenyl ring is disclosed. A contemplated resin contains (i) polymerized phenyl ring-containing monomers having a phosphonic acid ligand linked to the phenyl ring, (ii) about 2 to about 5 millimoles per gram (mmol/g) of phosphorus as phosphonic acid ligands, and (iii) a sufficient amount of a sulfonic acid ligand such that the ratio of mmol/g of phosphonic acid to mmol/g sulfonic acid is up to 3:1. A process for removing polyvalent metal cations from aqueous solution, and a process for removing iron(III) cations from acidic copper(II) cation-containing solutions that utilize the contemplated resin or other resins are disclosed.

  16. Synthesis, biological evaluation and molecular docking of N-phenyl thiosemicarbazones as urease inhibitors.

    PubMed

    Hameed, Abdul; Khan, Khalid Mohammed; Zehra, Syeda Tazeen; Ahmed, Ramasa; Shafiq, Zahid; Bakht, Syeda Mahwish; Yaqub, Muhammad; Hussain, Mazhar; de la Vega de León, Antonio; Furtmann, Norbert; Bajorath, Jürgen; Shad, Hazoor Ahmad; Tahir, Muhammad Nawaz; Iqbal, Jamshed

    2015-08-01

    Urease is an important enzyme which breaks urea into ammonia and carbon dioxide during metabolic processes. However, an elevated activity of urease causes various complications of clinical importance. The inhibition of urease activity with small molecules as inhibitors is an effective strategy for therapeutic intervention. Herein, we have synthesized a series of 19 benzofurane linked N-phenyl semithiocarbazones (3a-3s). All the compounds were screened for enzyme inhibitor activity against Jack bean urease. The synthesized N-phenyl thiosemicarbazones had varying activity levels with IC50 values between 0.077 ± 0.001 and 24.04 ± 0.14 μM compared to standard inhibitor, thiourea (IC50 = 21 ± 0.11 μM). The activities of these compounds may be due to their close resemblance of thiourea. A docking study with Jack bean urease (PDB ID: 4H9M) revealed possible binding modes of N-phenyl thiosemicarbazones. PMID:26119990

  17. Influence of the substituents on the electronic and electrochemical properties of a new square-planar nickel-bis(quinoxaline-6,7-dithiolate) system: synthesis, spectroscopy, electrochemistry, crystallography, and theoretical investigation.

    PubMed

    Bolligarla, Ramababu; Reddy, Samala Nagaprasad; Durgaprasad, Gummadi; Sreenivasulu, Vudagandla; Das, Samar K

    2013-01-01

    We describe the synthesis, crystal structures, electronic absorption spectra, and electrochemistry of a series of square-planar nickel-bis(quinoxaline-6,7-dithiolate) complexes with the general formula [Bu(4)N](2)[Ni(X(2)6,7-qdt)(2)], where X = H (1a), Ph (2a), Cl (3), and Me (4). The solution and solid-state electronic absorption spectral behavior and electrochemical properties of these compounds are strongly dependent on the electron donating/accepting nature of the substituent X, attached to the quinoxaline-6,7-dithiolate ring in the system [Bu(4)N](2)[Ni(X(2)6,7-qdt)(2)]. Particularly, the charge transfer (CT) transition bands observed in the visible region are greatly affected by the electronic nature of the substituent. A possible explanation for this influence of the substituents on electronic absorption and electrochemistry is described based on highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO) gaps, which is further supported by ground-state electronic structure calculations. In addition to this, the observed CT bands in all the complexes are sensitive to the solvent polarity. Interestingly, compounds 1a, 2a, 3, and 4 undergo reversible oxidation at very low oxidation potentials appearing at E(1/2) = +0.12 V, 0.033 V, 0.18 V, and 0.044 V vs Ag/AgCl, respectively, in MeOH solutions, corresponding to the respective couples [Ni(X(2)6,7-qdt)(2)](-)/[Ni(X(2)6,7-qdt)(2)](2-). Compounds 1a, 3, and 4 have been characterized unambiguously by single crystal X-ray structural analysis; compound 2a could not be characterized by single crystal X-ray structure determination because of the poor quality of the concerned crystals. Thus, we have synthesized the tetraphenyl phosphonium salt of the complex anion of 2a, [PPh(4)](2)[Ni(Ph(2)6,7-qdt)(2)]·3DMF (2b) for its structural characterization. PMID:23214512

  18. Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring.

    PubMed

    Kitaguchi, Yuya; Habuka, Satoru; Okuyama, Hiroshi; Hatta, Shinichiro; Aruga, Tetsuya; Frederiksen, Thomas; Paulsson, Magnus; Ueba, Hiromu

    2015-01-01

    Mechanical methods for single-molecule control have potential for wide application in nanodevices and machines. Here we demonstrate the operation of a single-molecule switch made functional by the motion of a phenyl ring, analogous to the lever in a conventional toggle switch. The switch can be actuated by dual triggers, either by a voltage pulse or by displacement of the electrode, and electronic manipulation of the ring by chemical substitution enables rational control of the on-state conductance. Owing to its simple mechanics, structural robustness, and chemical accessibility, we propose that phenyl rings are promising components in mechanical molecular devices. PMID:26665080

  19. 3-Acetyl-5-phenyl-1-p-tolyl-1H-pyrazole-4-carbonitrile

    PubMed Central

    Abdel-Aziz, Hatem A.; Ghabbour, Hazem A.; Chantrapromma, Suchada; Fun, Hoong-Kun

    2012-01-01

    In the title pyrazole derivative, C19H15N3O, the central pyrazole ring makes dihedral angles of 42.71 (9) and 61.34 (9)°, respectively, with the phenyl and p-tolyl rings. The dihedral angle between the phenyl and p-tolyl rings is 58.22 (9)°. The 3-acetyl-1H-pyrazole-4-carbonitrile unit is essentially planar, with an r.m.s. deviation of 0.0295 (1) Å for the ten non-H atoms. PMID:22606111

  20. Reaction dynamics of phenyl radicals in extreme environments: a crossed molecular beam study.

    PubMed

    Gu, Xibin; Kaiser, Ralf I

    2009-02-17

    Polycyclic aromatic hydrocarbons (PAHs)organic compounds that consist of fused benzene ringsand their hydrogen-deficient precursors have attracted extensive interest from combustion scientists, organic chemists, astronomers, and planetary scientists. On Earth, PAHs are toxic combustion products and a source of air pollution. In the interstellar medium, research suggests that PAHs play a role in unidentified infrared emission bands, diffuse interstellar bands, and the synthesis of precursor molecules to life. To build clean combustion devices and to understand the astrochemical evolution of the interstellar medium, it will be critical to understand the elementary reaction mechanisms under single collision conditions by which these molecules form in the gas phase. Until recently, this work had been hampered by the difficulty in preparing a large concentration of phenyl radicals, but the phenyl radical represents one of the most important radical species to trigger PAH formation in high-temperature environments. However, we have developed a method for producing these radical species and have undertaken a systematic experimental investigation. In this Account, we report on the chemical dynamics of the phenyl radical (C(6)H(5)) reactions with the unsaturated hydrocarbons acetylene (C(2)H(2)), ethylene (C(2)H(4)), methylacetylene (CH(3)CCH), allene (H(2)CCCH(2)), propylene (CH(3)CHCH(2)), and benzene (C(6)H(6)) utilizing the crossed molecular beams approach. For nonsymmetric reactants such as methylacetylene and propylene, steric effects and the larger cones of acceptance drive the addition of the phenyl radical to the nonsubstituted carbon atom of the hydrocarbon reactant. Reaction intermediates decomposed via atomic hydrogen loss pathways. In the phenyl-propylene system, the longer lifetime of the reaction intermediate yielded a more efficient energy randomization compared with the phenyl-methylacetylene system. Therefore, two reaction channels were open: hydrogen

  1. Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

    PubMed Central

    Kitaguchi, Yuya; Habuka, Satoru; Hatta, Shinichiro; Aruga, Tetsuya; Paulsson, Magnus; Ueba, Hiromu

    2015-01-01

    Summary Mechanical methods for single-molecule control have potential for wide application in nanodevices and machines. Here we demonstrate the operation of a single-molecule switch made functional by the motion of a phenyl ring, analogous to the lever in a conventional toggle switch. The switch can be actuated by dual triggers, either by a voltage pulse or by displacement of the electrode, and electronic manipulation of the ring by chemical substitution enables rational control of the on-state conductance. Owing to its simple mechanics, structural robustness, and chemical accessibility, we propose that phenyl rings are promising components in mechanical molecular devices. PMID:26665080

  2. Micro- or nanorod and nanosphere structures derived from a series of phenyl-porphyrins.

    PubMed

    Reddy, M Harsha Vardhan; Al-Shammari, Rusul M; Al-Attar, Nebras; Kennedy, Eamonn; Rogers, Luke; Lopez, Sergio; Senge, Mathias O; Keyes, Tia E; Rice, James H

    2014-03-01

    We examine here a series of meso-phenyl porphyrin micro- and nanostructures. Optical absorption and emission spectroscopy imaging and atomic force microscopy are used to investigate the effect of peripheral groups in nano- and microstructures of 5,10,15,20-tetraphenylporphyrin (H2TPP) compared to three other phenylporphyrins, i.e. 5,10,15-triphenylporphyrin (H2-Tri-PP), 5,10-diphenylporphyrin (H25,10-BPP) and 5,15-diphenylporphyrin (H25,15-BPP) molecules. We show that nanospheres and nanorods are formed, the occurrence and properties of which are influenced by the number and position of the phenyl substituents. PMID:24458009

  3. Targeting kinases with anilinopyrimidines: discovery of N-phenyl-N’-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives as selective inhibitors of class III receptor tyrosine kinase subfamily

    PubMed Central

    Gandin, Valentina; Ferrarese, Alessandro; Dalla Via, Martina; Marzano, Cristina; Chilin, Adriana; Marzaro, Giovanni

    2015-01-01

    Kinase inhibitors are attractive drugs/drug candidates for the treatment of cancer. The most recent literature has highlighted the importance of multi target kinase inhibitors, although a correct balance between specificity and non-specificity is required. In this view, the discovery of multi-tyrosine kinase inhibitors with subfamily selectivity is a challenging goal. Herein we present the synthesis and the preliminary kinase profiling of a set of novel 4-anilinopyrimidines. Among the synthesized compounds, the N-phenyl-N’-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives selectively targeted some members of class III receptor tyrosine kinase family. Starting from the structure of hit compound 19 we synthesized a further compound with an improved affinity toward the class III receptor tyrosine kinase members and endowed with a promising antitumor activity both in vitro and in vivo in a murine solid tumor model. Molecular modeling simulations were used in order to rationalize the behavior of the title compounds. PMID:26568452

  4. 40 CFR 721.10409 - Poly(oxyalkylenediyl), .alpha.-[[[methyl-3-[[[(polyfluoroalkyl)oxy]carbonyl] amino]phenyl]amino...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxyalkylenediyl), .alpha...(oxyalkylenediyl), .alpha.- carbonyl] amino]phenyl]amino]carbonyl]- .omega.-methoxy-(generic). (a) Chemical... as poly(oxyalkylenediyl), .alpha.- carbonyl]amino]phenyl]amino] carbonyl]-.omega.-methoxy- (PMN...

  5. 40 CFR 721.10409 - Poly(oxyalkylenediyl), .alpha.-[[[methyl-3-[[[(polyfluoroalkyl) oxy]carbonyl]amino]phenyl]amino...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Poly(oxyalkylenediyl), .alpha...(oxyalkylenediyl), .alpha.- carbonyl]amino]phenyl]amino] carbonyl]-.omega.-methoxy- (generic). (a) Chemical... as poly(oxyalkylenediyl), .alpha.- carbonyl]amino]phenyl]amino] carbonyl]-.omega.-methoxy- (PMN...

  6. Synthesis of 3-Methyl-4-(4-methylbenzoyl)-1-phenyl-pyrazol-5-One: How to Avoid O-Acylation

    ERIC Educational Resources Information Center

    Kurteva, Vanya B.; Petrova, Maria A.

    2015-01-01

    In this laboratory experiment, students synthesize 3-methyl-4-(4-methylbenzoyl)-1-phenyl-pyrazol-5-one by selective C-acylation of 3-methyl-1-phenyl-1H-pyrazol-5-one. Calcium hydroxide is used to push the tautomeric equilibrium toward the enol form, to protect the hydroxyl functionality as a complex, to trap the liberated hydrogen chloride, and to…

  7. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... identified generically as phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo...

  8. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... identified generically as phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo...

  9. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... identified generically as phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo...

  10. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... identified generically as phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo...

  11. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... identified generically as phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo...

  12. Photochemical synthesis and anticancer activity of barbituric acid, thiobarbituric acid, thiosemicarbazide, and isoniazid linked to 2-phenyl indole derivatives.

    PubMed

    Laxmi, S Vijaya; Rajitha, G; Rajitha, B; Rao, Asha Jyothi

    2016-04-01

    2-Phenyl-1H-indole-3-carbaldehyde-based barbituric acid, thiobarbituric acid, thiosemicarbazide, isoniazid, and malononitrile derivatives were synthesized under photochemical conditions. The antitumor activities of the synthesized compounds were evaluated on three different human cancer cell lines representing prostate cancer cell line DU145, Dwivedi (DWD) cancer cell lines, and breast cancer cell line MCF7. All the screened compounds possessed moderate anticancer activity, and out of all the screened compounds, 5-{1[2-(4-chloro-phenyl)2-oxo-ethyl]-2-phenyl-1H-indole-3-ylmethylene}-2-thioxo-dihydro-pyrimidine-4,6-dione (2b) and 5-{1[2-(4-methoxy-phenyl)2-oxo-ethyl]-2-phenyl-1H-indole-3-ylmethylene}-2-thioxo-dihydro-pyrimidine-4,6-dione (2d) exhibited marked antitumor activity against used cell lines. Additionally, barbituric acid derivatives were selective to inhibit cell line DWD and breast cancer cell lines. PMID:27118996

  13. Exerting control over the helical chirality in the main chain of sergeants-and-soldiers-type poly(quinoxaline-2,3-diyl)s by changing from random to block copolymerization protocols.

    PubMed

    Nagata, Yuuya; Nishikawa, Tsuyoshi; Suginome, Michinori

    2015-04-01

    Chiral random poly(quinoxaline-2,3-diyl) polymers of the sergeants-and-soldiers-type (sergeant units bearing (S)-3-octyloxymethyl groups) adopt an M- or P-helical conformation in the presence of achiral units bearing propoxymethyl or butoxy groups (soldier units), respectively. Unusual bidirectional induction of the helical sense can be observed for a copolymer with butoxy soldier units upon changing the mole fraction of the sergeant units. In the presence of 16-20% of sergeant units, the selective induction of a P-helix was observed, while the selective induction of an M-helix was observed for a mole fraction of sergeant units of more than 60%. This phenomenon could be successfully employed to control the helical chirality of copolymers by applying either random or block copolymerization protocols. Random or block copolymerization of sergeant and soldier monomers in a 18:82 ratio resulted in the formation of 250mers with almost absolute P- or M-helical conformation, respectively (>99% ee). Incorporation of a small amount of coordination sites into the random and block copolymers resulted in chiral macromolecular ligands, which allowed the enantioselective synthesis of both enantiomers in the Pd-catalyzed asymmetric hydrosilylation of β-methylstyrene. PMID:25793617

  14. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Carbon black, 4- phenyl-modified... Specific Chemical Substances § 721.10080 Carbon black, 4- phenyl-modified, hydrochlorides (generic). (a... generically as carbon black, 4- phenyl-modified, hydrochlorides (PMN P-06-8) is subject to reporting...

  15. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Carbon black, 4- phenyl-modified... Specific Chemical Substances § 721.10080 Carbon black, 4- phenyl-modified, hydrochlorides (generic). (a... generically as carbon black, 4- phenyl-modified, hydrochlorides (PMN P-06-8) is subject to reporting...

  16. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Carbon black, 4- phenyl-modified... Specific Chemical Substances § 721.10080 Carbon black, 4- phenyl-modified, hydrochlorides (generic). (a... generically as carbon black, 4- phenyl-modified, hydrochlorides (PMN P-06-8) is subject to reporting...

  17. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Carbon black, 4- phenyl-modified... Specific Chemical Substances § 721.10080 Carbon black, 4- phenyl-modified, hydrochlorides (generic). (a... generically as carbon black, 4- phenyl-modified, hydrochlorides (PMN P-06-8) is subject to reporting...

  18. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Carbon black, 4- phenyl-modified... Specific Chemical Substances § 721.10080 Carbon black, 4- phenyl-modified, hydrochlorides (generic). (a... generically as carbon black, 4- phenyl-modified, hydrochlorides (PMN P-06-8) is subject to reporting...

  19. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... significant new uses subject to reporting. (1) The chemical substances identified generically as...

  20. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  1. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  2. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  3. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  4. 1-(2,6-Diisopropyl­phen­oxy)-4-phenyl­phthalazine

    PubMed Central

    Tong, Bihai; Mei, Qunying

    2012-01-01

    In the title mol­ecule, C26H26N2O, the phenyl and phen­oxy rings form dihedral angles of 54.66 (7) and 84.83 (6)°, respectively, with the phthalazine mean plane. The crystal packing exhibits weak C—H⋯π inter­actions. PMID:22905005

  5. 40 CFR 721.275 - Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.275 Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical...

  6. 40 CFR 721.275 - Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.275 Halogenated-N-(2-propenyl)-N-(substituted phenyl) acetamide. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical...

  7. 40 CFR 721.10300 - Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester. 721.10300 Section 721.10300 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10300 Benzeneacetic acid,...

  8. 40 CFR 721.10300 - Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester. 721.10300 Section 721.10300 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10300 Benzeneacetic acid,...

  9. 40 CFR 721.10300 - Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzeneacetic acid, .alpha.-chloro-.alpha.-phenyl-, ethyl ester. 721.10300 Section 721.10300 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.10300 Benzeneacetic acid,...

  10. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... phenyl substituted carbonyl- (PMN P-00-368) is subject to reporting under this section for the... in § 721.125(a), (b), (c), (d), (f), (g), (h), and (k) are applicable to manufacturers, importers... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF...