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Sample records for 6 4 2

  1. 2,4,6-Trichlorophenol

    Integrated Risk Information System (IRIS)

    2,4,6 - Trichlorophenol ; CASRN 88 - 06 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  2. 2,4-/2,6-Dinitrotoluene mixture

    Integrated Risk Information System (IRIS)

    2,4 - / 2,6 - Dinitrotoluene mixture ; no CASRN Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  3. 2,3,4,6-Tetrachlorophenol

    Integrated Risk Information System (IRIS)

    2,3,4,6 - Tetrachlorophenol ; CASRN 58 - 90 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  4. 2,4,6-Trinitrotoluene (TNT)

    Integrated Risk Information System (IRIS)

    2,4,6 - Trinitrotoluene ( TNT ) ; CASRN 118 - 96 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for N

  5. 2,4-/2,6-Toluene diisocyanate mixture (TDI)

    Integrated Risk Information System (IRIS)

    2,4 - / 2,6 - Toluene diisocyanate mixture ( TDI ) ; CASRN 26471 - 62 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Haz

  6. 10 CFR 960.4-2-6 - Dissolution.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Dissolution. 960.4-2-6 Section 960.4-2-6 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-6 Dissolution. (a) Qualifying condition. The site shall...

  7. 10 CFR 960.4-2-6 - Dissolution.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Dissolution. 960.4-2-6 Section 960.4-2-6 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-6 Dissolution. (a) Qualifying condition. The site shall...

  8. 10 CFR 960.4-2-6 - Dissolution.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Dissolution. 960.4-2-6 Section 960.4-2-6 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-6 Dissolution. (a) Qualifying condition. The site shall...

  9. 10 CFR 960.4-2-6 - Dissolution.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Dissolution. 960.4-2-6 Section 960.4-2-6 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-6 Dissolution. (a) Qualifying condition. The site shall...

  10. 10 CFR 960.4-2-6 - Dissolution.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Dissolution. 960.4-2-6 Section 960.4-2-6 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-6 Dissolution. (a) Qualifying condition. The site shall...

  11. Two-dimensional polymeric [Hg42-I)6I22-C4S6)]n

    PubMed Central

    Hameau, Aurélien; Guyon, Fabrice; Knorr, Michael; Colquhoun, Victoria P.; Strohmann, Carsten

    2011-01-01

    The title compound, poly[(μ2-2H,5H-1,3-dithiolo[4,5-d][1,3]di­thiole-2,5-dithione)hexa-μ2-iodido-diiodidotetra­mercury(II)], [Hg4I8(C4S6)]n, represents the first example of a coordination polymer assembled by the α,α-C4S6 dithione ligand. The HgII ions are four-coordinated in a distorted tetra­hedral geometry, the coordination demand being satisfied either by four bridging iodide ligands or by three iodide ligands (one terminal and two bridging) and a thio­carbonyl S atom. Due to the bridging nature of the dithione ligand, the coordination polymer has a two-dimensional structure, built up of undulated layers parallel to (001). There is an inversion center at the mid-point of the central C=C double bond. PMID:21522307

  12. 3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, its 4-methylphenyl analogue, and a potassium salt of 2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid.

    PubMed

    Nye, Luke; Turnbull, Mark M; Wikaira, Jan L

    2013-11-01

    Reaction of 4-methoxyacetophenone with diethyl oxalate under basic conditions produced 3,4-dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, C20H18O6, (1). The molecules lie across a crystallographic inversion centre and intramolecular hydrogen bonding, similar to acetylacetone, is observed, confirming that the molecule is in the di-enol-dione tautomeric form. Additional O-H...O hydrogen bonds link the molecules into chains parallel to the b axis. The structure is compared with that of redetermined 4-methylphenyl compound 3,4-dihydroxy-1,6-bis(4-methylphenyl)hexa-2,4-diene-1,6-dione, C20H18O4, (2), which crystallizes in a similar fashion. The salt, catena-poly[[μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoato-κ(3)O(1),O(2):O(4)][μ2-2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid-κ(2)O(1):O(4)]potassium], [K(C11H9O5)(C11H10O5)]n, (3), was isolated as a by-product of the synthesis of (1). The two organic species are linked by a strong hydrogen bond between the carboxylic acid and carboxylate groups. They are further stabilized and linked into a double-chain structure via the seven-coordinate potassium ion.

  13. 40 CFR 180.437 - Methyl 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-p-toluate and methyl 6-(4-isopropyl-4...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-imidazolin-2-yl)-p-toluate and methyl 6-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-m-toluate; tolerances... Tolerances § 180.437 Methyl 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-p-toluate and methyl 6-(4... for the combined residues of the herbicide methyl...

  14. Antibacterial activity of 2-(2',4'-dibromophenoxy)-4,6-dibromophenol from Dysidea granulosa.

    PubMed

    Shridhar, Divya M P; Mahajan, Girish B; Kamat, Vijayendra P; Naik, Chandrakant G; Parab, Rajashri R; Thakur, Nidhi R; Mishra, Prabhu D

    2009-09-22

    2-(2',4'-Dibromophenoxy)-4,6-dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity, especially against methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), vancomycin resistant Enterococci (VRE), vancomycin sensitive Enterococci (VSE) and Bacillus spp. Minimal inhibitory concentration (MIC) was evaluated against 57 clinical and standard strains of Gram positive and Gram negative bacteria. The observed MIC range was 0.117-2.5 microg/mL against all the Gram positive bacteria and 0.5-2 microg/mL against Gram negative bacteria. The in-vitro antibacterial activity observed was better than that of the standard antibiotic linezolid, a marketed anti-MRSA drug. The results establish 2-(2',4'-dibromophenoxy)-4,6-dibromophenol, as a potential lead molecule for anti-MRSA and anti-VRE drug development.

  15. 2,4,6-TRINITROTOLUENE TRANSFORMATION IN PLANTED, SOIL COLUMNS

    EPA Science Inventory

    2,4,6-Trinitrotoluene (TNT), has been used extensively by the United States military to manufacture explosive devices. Since the conclusion of World War 11, many of these military installations have also been involved in the disposal of surplus and outdated explosives. Both the c...

  16. Anaerobic transformation of 2,4,6-trinitrotoluene (TNT).

    PubMed

    Preuss, A; Fimpel, J; Diekert, G

    1993-01-01

    A sulfate-reducing bacterium using trinitrotoluene (TNT) as the sole nitrogen source was isolated with pyruvate and sulfate as the energy sources. The organism was able to reduce TNT to triaminotoluene (TAT) in growing cultures and cell suspensions and to further transform TAT to still unknown products. Pyruvate, H2, or carbon monoxide served as the electron donors for the reduction of TNT. The limiting step in TNT conversion to TAT was the reduction of 2,4-diamino-6-nitrotoluene (2,4-DANT) to triaminotoluene. The reduction proceeded via 2,4-diamino-6-hydroxylaminotoluene (DAHAT) as an intermediate. The intermediary formation of DAHAT was only observed in the presence of carbon monoxide or hydroxylamine, respectively. The reduction of DAHAT to triaminotoluene was inhibited by both CO and NH2OH. The inhibitors as well as DANT and DAHAT significantly inhibited sulfide formation from sulfite. The data were taken as evidence for the involvement of dissimilatory sulfite reductase in the reduction of DANT and/or DAHAT to triaminotoluene. Hydrogenase purified from Clostridium pasteurianum and carbon monoxide dehydrogenase partially purified from Clostridium thermoaceticum also catalyzed the reduction of DANT in the presence of methyl viologen or ferredoxin, however, as the main reduction product DAHAT rather than triaminotoluene was formed. The findings could explain the function of CO as an electron donor for the DANT reduction (to DAHAT) and the concomitant inhibitory effect of CO on triaminotoluene formation (from DAHAT) by the inhibition of sulfite reductase.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. 6-Chloro-N 4,N 4-dimethyl­pyrimidine-2,4-diamine

    PubMed Central

    Pang, Yuan-Yuan; Yu, Kai; Sun, Bin; Guo, Dian-Shun

    2012-01-01

    The asymmetric unit of the title compound, C6H9ClN4, contains four independent mol­ecules (A, B, C and D). Their main difference is the torsion angles, ranging from 1.6 (5) to 5.9 (5)°, between the methyl group and the pyrimidine plane. A pair of inter­molecular N—H⋯N hydrogen bonds link mol­ecules A and C into a twisted dimer with a dihedral angle of 32.9 (1)° between the two pyrimidine rings, creating an R 2 2(8) motif. In the packing, each two mol­ecules of B, C and D form centrosymmetric dimers through two inter­molecular N—H⋯N hydrogen bonds, locally creating R 2 2(8) motifs. The dimers of C and D are alternately bridged by A into an infinite zigzag strip, locally creating two different R 2 2(8) motifs with dihedral angles of 32.9 (1) and 63.4 (1)° between the pyrimidine rings. Finally, these strips together with the dimers of B associate into a complicated three-dimensional framework. PMID:22590204

  18. 4,4',4"-trimethyl-2,2':6',2"-terpyridine by oxidative coupling of 4-picoline.

    PubMed

    Robo, Michael T; Prinsell, Michael R; Weix, Daniel J

    2014-11-07

    Alkylated terpyridine ligands are an increasingly important component of catalysis and dyes but are costly because their synthesis is challenging and often low-yielding. We report an improved method for the Pd/C-catalyzed dehydrogenative coupling of 4-picoline to form the bi- and terpyridine. The addition of MnO2 improves the yield of the reaction, making the reaction useful on a large scale (up to 200 mmol). The use of Pd(OAc)2 or Pd/C/pivalic acid leads to the selective formation of bipyridine.

  19. Structural study of 2,4,6-triisopropylbenzenesulfonyl chloride

    SciTech Connect

    Laba, V. I. Sviridova, A. V.; Nesterov, V. N.

    2009-01-15

    The structure of 2,4,6-triisopropylbenzenesulfonyl chloride (TPSCl) (I) was studied by X-ray diffraction. Compound I is a highly selective condensing agent first suggested by Khorana for the formation of the C3'-C5' interribonucleotide linkage in the oligo- and polyribonucleotide synthesis. I crystals are orthorhombic. At -120 deg. C, the unit-cell parameters are a = 14.184(4) A, b = 11.344(5) A, c = 19.883(6) A, V = 3199(2) A{sup 3}, d{sub calc} = 1.257 g/cm{sup 3}, Z = 8, sp. gr. Pbca. Molecule I adopts a strongly flattened boat conformation with the carbon atoms C-SO{sub 2}Cl (C{sub 1}) and C-i-Pr (C4) of the benzene ring deviating from the bottom of the boat by 0.065(1) and 0.032(1) A, respectively. Molecule I is sterically overcrowded, resulting in an increase in the bond lengths and bond-angle distortions in the fragment containing the SO{sub 2}Cl group and two ortho-i-Pr groups. Nonbonded contacts that are present in the molecule can be considered weak intramolecular hydrogen bonds (for example, the (CH{sub 3}){sub 2}C-H-O=S bond). There is no rotation of the SO{sub 2}Cl, ortho-i-Pr, and CH{sub 3} groups. The above-mentioned facts are, apparently, responsible for the specific selectivity of TPSCl. New readily available sterically hindered arenesulfonyl chlorides were designed.

  20. 1,2,3,3',4',6'-Hexaacetyl-4,6-O-benzyl-idenesucrose.

    PubMed

    Brito-Arias, Marco A; Soto-Ortega, Miguel; García-Báez, Efrén V

    2011-01-26

    In the title compound, C(31)H(38)O(17), the 1,3-dioxane and pyran-oside rings both show (4)C(1) chair conformations while for the d-fructofuran-oside moiety an envelop 3E conformation is observed. The phenyl ring is oriented almost perpendicular to the 1,3-dioxane ring [dihedral angle = 79.3 (2)°], and the acetate groups are equatorial for the pyran-oside ring and axial for the furan-oside ring. The analysis of potential hydrogen bonds shows both intra- and inter-molecular C-H⋯O contacts to be present.

  1. Diastereoselective synthesis of 2,3,4,5,6-pentafluoroheptanes.

    PubMed

    Farran, Daniel; Slawin, Alexandra M Z; Kirsch, Peer; O'Hagan, David

    2009-09-18

    A stereocontrolled synthesis of alkanes containing five contiguous fluorine atoms is presented. The compounds were prepared by sequential fluorination of diastereoisomeric alcohol-diepoxides. The chemistry involved epoxide ring-opening with HF.NEt(3) and deshydroxyfluorination reactions of free alcohols with Deoxo-Fluor. The fluorination reactions were all highly stereospecific, with all five fluorines being incorporated in three sequential steps. Three different diastereoisomers of the 2,3,4,5,6-pentafluoroheptyl motif were prepared as heptane-1,7-diol derivatives, a structural format amenable for incorporation of the vicinal pentafluoro scaffold into larger molecular architectures.

  2. Adsorption of 2,4,6-trinitrotoluene and 4-amino-2,6-dinitrotoluene in two soil environments

    SciTech Connect

    Wood, A.J.; Tiller, C.L.

    1996-10-01

    Soil contamination by 2,4,6-trinitrotoluene (TNT) and its byproducts is common among Army Ammunition Plants (AAPs). The purpose of this research is to quantify the behavior of TNT in the Alabama AAP soil environment. Uncontaminated soil collected from two different depths at the site was used, one with relatively high organic content and one with low organic content. Adsorption kinetic tests for both TNT and a primary biotransformation byproduct 4-amino-2,6-dinitrotoluene (4A26DNT), alone and in combination, were performed and adsorption isotherms were developed. Results indicate a faster rate of adsorption for 4A26DNT than for TNT, as well as a larger extent of adsorption when the two compounds are both present. As expected, incubation time was shown to affect the extent of adsorption as well as the extractability and transformation of TNT. Large differences in kinetic patterns were obtained for each soil. Isotherm shape was similar for both soils, however extent of adsorption differed by several orders of magnitude.

  3. Synthesis of 3-cyano-4-aryl-5-ethoxycarbonyl-6-methyl-3,4-dihydropyridine-2-thiones

    SciTech Connect

    Krauze, A.A.; Liepin'sh, E.E.; Pelcher, Yu.E.; Kalme, Z.A.; Dipan, I.V.; Dubur, G.Ya.

    1985-12-01

    The condensation of ethyl arylidenacetoacetate with cyanothioacetamide and of arylidenecyanothioacetamides with ethyl acetoacetate or of arylidenecyanothioacetamides with ethyl ..beta..-aminocrotonate gave 3-cyano-4-aryl-5-ethoxycarbonyl-6-methyl-3,4-dihydropyridine-2-thiones. PMR spectroscopy showed that the 3-cyano-4-aryl-3,4-dihydro-pyridine-2-thiones are formed as a mixture of cis and trans isomers.

  4. Spiro[2.4]hepta-4,6-dienes: synthesis and application in organic synthesis

    NASA Astrophysics Data System (ADS)

    Menchikov, L. G.; Nefedov, O. M.

    2016-03-01

    This review integrates and describes systematically the data in the field of spiro[2.4]hepta-4,6-dienes published in the past 15 years. The changes in the development of studies that took place during this period are noted. The methods for the synthesis, the reactivity details and key chemical transformations of spiro[2.4]hepta-4,6-dienes are considered, with the emphasis on applications of these compounds in organic synthesis. The bibliography includes 207 references.

  5. Aerobic biotransformation and mineralization of 2,4,6-trinitrotoluene

    SciTech Connect

    Bae, B.H.; Autenrieth, R.L.; Bonner, J.S.

    1995-12-31

    Respirometric mineralization studies of 2,4,6-trinitrotoluene (TNT) were conducted with microorganisms isolated from a site contaminated with munitions waste in Illinois. Nine aerobic bacterial species were isolated under a carbon- and nitrogen-limited condition and tentatively identified as: one Pseudomonas species; one Enterobacter species; and seven Alcaligenes species. Experiments were performed using each of the nine organisms individually and with a consortium of all nine bacterial species. The aerobic microorganisms were cultured in a sterile nutrient solution with glucose and 20 mg/L TNT. Mineralization was determined using uniformly ring-labeled {sup 14}C-TNT in a respirometer that trapped the evolved CO{sub 2}. Biodegradation behavior was characterized based on oxygen consumption, distribution of {sup 14}C activity, and high-performance liquid chromatography (HPLC) analysis of TNT and its transformation products.

  6. Children Learn Physical Skills. Volume 2. 4 to 6 Years.

    ERIC Educational Resources Information Center

    Diem, Liselott

    The physical development of the child from 4 to 6 years old is discussed. Activities and games that will increase the child's dexterity, balance, and ability to play with others are described and illustrated. (JD)

  7. Solubility of Fe-ettringite (Ca 6[Fe(OH) 6] 2(SO 4) 3 · 26H 2O)

    NASA Astrophysics Data System (ADS)

    Möschner, Göril; Lothenbach, Barbara; Rose, Jerome; Ulrich, Andrea; Figi, Renato; Kretzschmar, Ruben

    2008-01-01

    The solubility of Fe-ettringite (Ca 6[Fe(OH) 6] 2(SO 4) 3 · 26H 2O) was measured in a series of precipitation and dissolution experiments at 20 °C and at pH-values between 11.0 and 14.0 using synthesised material. A time-series study showed that equilibrium was reached within 180 days of ageing. After equilibrating, the solid phases were analysed by XRD and TGA while the aqueous solutions were analysed by ICP-OES (calcium, sulphur) and ICP-MS (iron). Fe-ettringite was found to be stable up to pH 13.0. At higher pH-values Fe-monosulphate (Ca 4[Fe(OH) 6] 2(SO 4) · 6H 2O) and Fe-monocarbonate (Ca 4[Fe(OH) 6] 2(CO 3) · 6H 2O) are formed. The solubilities of these hydrates at 25 °C are: Ca[Fe(OH)]2(SO)3·26HO⇆6Ca+2Fe(OH)4-+3SO42-+4OH+26HO,logK=-44.0±0.7,Ca[Fe(OH)]2(SO)·6HO⇆4Ca+2Fe(OH)4-+SO42-+4OH+6HO,logK=-33.2±0.5andCa[Fe(OH)]2(CO)·6HO⇆4Ca+2Fe(OH)4-+CO32-+4OH+6HO,logK=-35.5±0.3.

  8. Toxicokinetics of 2,4- and 2,6-toluenediamine in hydrolysed urine and plasma after occupational exposure to 2,4- and 2,6- toluene diisocyanate.

    PubMed Central

    Lind, P; Dalene, M; Skarping, G; Hagmar, L

    1996-01-01

    OBJECTIVES: To assess the toxicokinetics of 2,4- and 2,6- toluenediisocyanate (TDI) in chronically exposed subjects. METHODS: Blood and urine, from 11 workers at two flexible foam polyurethane production plants, were sampled. By gas chromatography-mass spectrometry (GC-MS) 2,4- and 2,6-toluene diamine (TDA) were measured as pentafluoropropionic anhydride (PFPA) derivatives after acidic hydrolysis of plasma (P-TDA, ng/ml) and urine (U-TDA, microgram/h). RESULTS: In one of the plants the P-2,4-TDA concentrations were 0.4-1 ng/ml before a four to five week holiday and 0.2-0.5 ng/ml afterwards. The corresponding values for P-2,6-TDA were 2-6 and 0.5-2 ng/ml respectively. In the other plant the P-2,4-TDA concentrations were 2-23 ng/ml before the holiday and 0.5-6 ng/ml afterwards and the P-2,6-TDA concentrations were 7-24 ng/ml before and 3-6 ng/ml afterwards. The P-2,4-TDA concentrations were 2-24 ng/ml before a 12 day holiday, and 1-14 ng/ml afterwards. The corresponding values for P-2,6-TDA were 12-29 and 8-17 ng/ml, respectively. The urinary elimination rates (U-TDA, microgram/h) for 2,4-TDA before the holiday were 0.04-0.54 and 0.02-0.18 microgram/h afterwards. The corresponding values for 2,6-TDA were 0.18-0.76 microgram/h before and 0.09-0.27 microgram/h after the holiday. The half life in urine ranged between 5.8 and 11 days for 2,4- and 2,6-TDA. The differences in exposure were reflected by the P-TDA concentrations. The mean half life in plasma was 21 (range 14-34) days for 2,4-TDA and 21 (16-26) days for 2,6-TDA. The TDI air concentrations varied between 0.4 and 4 micrograms/m3 in one plant and in the other between 10 and 120 micrograms/m3. CONCLUSIONS: The half life in plasma of chronically exposed workers for 2,4-and 2,6-TDA was twice as long as for volunteers with short term exposure. An indication of a two phase elimination pattern in urine was found. The first phase was related to the more recent exposure and the second, much slower one was probably

  9. 40 CFR 180.341 - 2,4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4-octylphenyl crotonate; tolerances for...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.341 2,4-Dinitro-6-octylphenyl...-octylphenyl crotonate and 2,6-dinitro-4-octylphenyl crotonate in or on raw agricultural commodities as...

  10. BIOTRANSFORMATION OF 2,4,6-TRINITROTOLUENE (TNT) BY A PLANT-ASSOCIATED FUNGUS FUSARIUM OXYSPORUM

    EPA Science Inventory

    The capability of a plant-associated fungus, Fusarium oxyvorum, to transform TNT in liquid cultures was investigated. TNT was transformed into 2-amino-4, 6-dinitrotoluene (2-A-DNT), 4-amino-2, 6-dinitrotoluene (4-A- DNT), and 2, 4-diamino-6-nitrotoluene (2, 4-DAT) via 2- and 4-hy...

  11. 40 CFR 180.341 - 2,4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4-octylphenyl crotonate; tolerances for...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and 2,6-dinitro-4-octylphenyl crotonate; tolerances for residues. 180.341 Section 180.341 Protection... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.341 2,4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4-octylphenyl crotonate; tolerances for residues. (a) General. Tolerances...

  12. Synthesis and biological activity of cocaine analogues. 2. 6H-[2]Benzopyrano[4,3-c]pyridin-6-ones.

    PubMed

    Lazer, E S; Hite, G J; Nieforth, K A; Stratford, E S

    1979-07-01

    1,2,3,4-Tetrahydro-2-methyl-6H-[2]benzopyrano[4,3-c]pyridin-6-one (20) and cis- and trans-1,2,3,4,4a,10b-hexahydro-2-methyl-6H-[2]benzopyrano[4,3-c]pyridin-6-one (3a and 3b) were synthesized. The design of 3b was based on the proposal that the active conformation of cocaine is one in which the phenyl and amino groups are arranged in a manner that will superimpose upon a beta-phenethylamine in a trans-staggered conformation. The compounds were compared with cocaine and tropacocaine for their ability to inhibit uptake of [3H]norepinephrine by rat brain synaptosomal preparations. The test compounds (IC50 = 3.2 X 10(-4) M, 20; 6.5 X 10(-4) M, 3a; and 3.2 X 10(-4) M, 3b; respectively) were considerably weaker than cocaine (IC50 = 5.8 X 10(-7) M) and tropacocaine (IC50 = 5.6 X 10(-6) M). Compound 3b showed selectivity at 1 X 10(-5) M for inhibiting the uptake of norepinephrine (36%). It inhibited dopamine (3%) and serotonin (0%) uptake to a much lesser extent, if at all, at this concentration.

  13. Hydrogen-bonded supramolecular motifs in 2-amino-4,6-dimethoxypyrimidinium 4-hydroxybenzoate monohydrate, 2-amino-4,6-dimethoxypyrimidinium 6-carboxypyridine-2-carboxylate monohydrate and 2-amino-4,6-dimethoxypyrimidinium hydrogen (2R,3R)-tartrate 2-amino-4,6-dimethoxypyrimidine.

    PubMed

    Thanigaimani, Kaliyaperumal; Muthiah, Packianathan Thomas; Lynch, Daniel E

    2007-05-01

    In the crystal structures of the title compounds, C(6)H(10)N(3)O(2)+.C(7)H(5)O(3)-.H2O, (I), C(6)H(10)N(3)O(2)+.C(7)H(4)NO(4)-.H2O, (II), and C(6)H(10)N(3)O(2)+.C(4)H(5)O(6)-.C(6)H(9)N(3)O(2), (III), the 2-amino-4,6-dimethoxypyrimidinium cation [abbreviated as (MeO)2-Hampy+] interacts with the carboxylate group of the corresponding anion through a pair of nearly parallel N-H...O hydrogen bonds to form R(2)(2)(8) ring motifs. In (I), the (MeO)2-Hampy+ cation is centrosymmetrically paired through a pair of N-H...N hydrogen bonds involving the 2-amino group and a ring N atom forming an R(2)(2)(8) motif. In (II), inversion-related R(2)(2)(8) motifs (amino-pyrimidine-carboxylate motifs) are further bridged by N-H...O hydrogen bonds on either side forming a DDAA array of quadruple hydrogen bonds. This array is extended further on either side by O(water)-H...O(methoxy) hydrogen bonds, resulting in an array of six hydrogen bonds (ADDAAD). The water molecule plays a pivotal role, and five hydrogen-bonded fused rings are formed around the water molecule. In (III), the carboxy group of the tartrate anion interacts with the ring N atom and 2-amino group of the neutral (MeO)2-ampy molecule through N-H...O and O-H...N hydrogen bonds. There is also an intramolecular O-H...O hydrogen bond in the tartrate anion. In all three crystal structures, C-H...O hydrogen bonds are observed.

  14. Nqrs Data for C6H16I2N4O8 [C6H14N4O2·2(HIO3)] (Subst. No. 0932)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C6H16I2N4O8 [C6H14N4O2·2(HIO3)] (Subst. No. 0932)

  15. [Analysis of 2,4-dibromophenol and 2,6-dibromophenol in phenolic-smelling flatfish].

    PubMed

    Tanaka, Yasuo; Takahashi, Kyoko; Hosoi, Shiro; Hidaka, Toshio; Nakazawa, Hiroyuki

    2009-12-01

    A simple analytical method for dibromophenols (DBPs) in flatfiish was developed. 2,4-DBP and 2,6-DBP were extracted from a sample with acetone and n-hexane, cleaned up by treatment with conc. sulfuric acid and concentrated under a stream of nitrogen gas. The resulting extract was subjected to GC/MS. The recoveries of 2,4-DBP and 2,6-DBP were 89.4-96.5% and 81.4-86.2%, respectively, indicating that this method is useful for analysis of 2,4-DBP and 2,6-DBP. In the phenolic-smelling flatfish, 2,6-DBP was detected at the levels of 0.10 microg/g and 0.01 microg/g in skin and muscle, respectively, and 2,4-DBP was detected at the level of 0.02 microg/g in skin.

  16. 4-Benzyl-6-bromo-2-phenyl-4H-imidazo[4,5-b]pyridine

    PubMed Central

    Ouzidan, Y.; Obbade, S.; Capet, F.; Essassi, El Mokhtar; Ng, Seik Weng

    2010-01-01

    The imidazopyridine fused ring in the title compound, C19H14BrN3, is almost coplanar with the phenyl ring at the 2-position of the five-membered ring [dihedral angle = 2.4 (1). The crystal structure features short Br⋯Br contacts [3.562 (1) Å]. PMID:21580750

  17. Characterization of a New Organic-Cation Cyclotetraphosphate: (1,4-HOC 6H 4NH 3) 4P 4O 12· 6H 2O

    NASA Astrophysics Data System (ADS)

    Soumhi, E. H.; Saadoune, I.; Driss, A.; Jouini, T.

    1999-05-01

    The tetra(para-phenolammonium)cyclotetraphosphate hexahydrate, (1,4-HOC6H4NH3)4P4O12· 6H2O (M=864.51 g mol-1), is monoclinicP21/cwith the unit cell parametersa=9.836(2) Å,b=8.591(1) Å,c:22.769(5) Å,β=95.41(2)°. The structure of this compound can be described as a succession of inorganic and organic sheets parallel to the (001) plane. The existence of the OH and NH3groups in positionparato the organic cation leads to the cohesion of the inorganic sheets, forming a three-dimensional network.The IR spectrum of (1,4-HOC6H4NH3)4P4O12· 6H2O is reported and discussed according to the theoretical group analysis. The IR data confirm the atomic arrangement within the structure. The coupled TG-DTA thermal study shows the successive departure of four and two water molecules, confirming the hydrated character of this cyclophosphate.

  18. Preparation and properties of piperidine salts of 6-hydroxy-4,6-diaryl-5-ethoxycarbonyl-3-cyanopiperidine-2-thiones

    SciTech Connect

    Krauze, A.A.; Liepin'sh, E.E.; Pelcher, Yu.E.; Kalme, Z.A.; Dubur, G.Ya.

    1987-07-01

    Alkylation of piperidine salts of 6-hydroxy-4,6-diaryl-5-ethoxycarbonyl-3-cyanopiperidine-2(1H)-thiones yielded 6-hydroxy-2-alkylthio-4,6-diaryl-5-ethoxycarbonyl-1-3-cyano-3,4,5,6-tetrahydropyridines which were dehydrogenated with the formation of 2-methylthio-1,4- and 4,5-dihydropyridines. The oxidation of the compounds prepared has been studied.

  19. Rietveld refinement, electronic structure and ionic conductivity of Sr4La6(SiO4)6F2 and Sr4La6(SiO4)6O ceramics

    NASA Astrophysics Data System (ADS)

    Boughzala, Khaled; Debbichi, Mourad; Njema, Hela; Bouzouita, Khaled

    2016-07-01

    In this paper, we report the effect of the tunnel anions on the ionic conductivity of Strontium-Lanthanum silicate apatites. The Sr4La6(SiO4)6F2 and Sr4La6(SiO4)6O ceramics were prepared by the solid state reaction method. X-ray diffraction, NMR spectroscopy and Raman measurements were performed to investigate the crystal structure and vibrational active modes. Moreover, the electronic structures of the crystals were evaluated by the first-principles quantum mechanical calculation based on the density functional theory. Finally, the ionic conductivity was studied according to the complex impedance method.

  20. Biological Degradation of 2,4,6-Trinitrotoluene

    PubMed Central

    Esteve-Núñez, Abraham; Caballero, Antonio; Ramos, Juan L.

    2001-01-01

    Nitroaromatic compounds are xenobiotics that have found multiple applications in the synthesis of foams, pharmaceuticals, pesticides, and explosives. These compounds are toxic and recalcitrant and are degraded relatively slowly in the environment by microorganisms. 2,4,6-Trinitrotoluene (TNT) is the most widely used nitroaromatic compound. Certain strains of Pseudomonas and fungi can use TNT as a nitrogen source through the removal of nitrogen as nitrite from TNT under aerobic conditions and the further reduction of the released nitrite to ammonium, which is incorporated into carbon skeletons. Phanerochaete chrysosporium and other fungi mineralize TNT under ligninolytic conditions by converting it into reduced TNT intermediates, which are excreted to the external milieu, where they are substrates for ligninolytic enzymes. Most if not all aerobic microorganisms reduce TNT to the corresponding amino derivatives via the formation of nitroso and hydroxylamine intermediates. Condensation of the latter compounds yields highly recalcitrant azoxytetranitrotoluenes. Anaerobic microorganisms can also degrade TNT through different pathways. One pathway, found in Desulfovibrio and Clostridium, involves reduction of TNT to triaminotoluene; subsequent steps are still not known. Some Clostridium species may reduce TNT to hydroxylaminodinitrotoluenes, which are then further metabolized. Another pathway has been described in Pseudomonas sp. strain JLR11 and involves nitrite release and further reduction to ammonium, with almost 85% of the N-TNT incorporated as organic N in the cells. It was recently reported that in this strain TNT can serve as a final electron acceptor in respiratory chains and that the reduction of TNT is coupled to ATP synthesis. In this review we also discuss a number of biotechnological applications of bacteria and fungi, including slurry reactors, composting, and land farming, to remove TNT from polluted soils. These treatments have been designed to achieve

  1. Compounds 2,4,6-trinitrotoluene and 2,4-diamino-6-nitrotoluene: The absence of recA-dependent mutagenesis

    SciTech Connect

    Karamova, N.S.; Mynina, I.I.; Garaeva, G.G.

    1995-05-01

    The genotoxicity of 2,4,6-trinitrotoluene (2,4,6-TNT) and its amino derivative, 2,4-diamino-6-nitrotoluene (2,4-DA-6-NT), was studied using the Escherichia coli tester strain PQ37 in the SOS chromotest. The compound 2,4,6-TNT, without metabolic activation, virtually failed to induce an SOS effect in cells of the tester bacteria. Consequently, mutagenic activity of 2,4,6-TNT, which was shown earlier in the Ames test, does not depend on SOS mutagenesis. It was demonstrated that metabolic activation with the microsomal S9 human placenta fraction results in a threefold increase in the induction factor of the SOS effect caused by 2,4,6-TNT. The absence of the SOS-inducing activity of 2,4-DA-6-NT, regardless of the presence of a microsomal activating mixture, is shown. Thus, 2,4-DA-6-NT does not belong to metabolites of 2,4,6-TNT, responsible for the genotoxicity of this compound. 25 refs., 1 fig., 2 tabs.

  2. 4,6-Dimethyl-2-p-tolyl­pyrimidine

    PubMed Central

    Xu, Chen; Wang, Zhi-Qiang; Cen, Fei-Fei; Cheng, Lin; Ji, Bao-Ming

    2009-01-01

    The mol­ecule of the title compound, C13H14N2, is located on a crystallographic mirror plane. The aromatic rings make a dihedral angle of 3.4 (2)°. The H atoms of the methyl groups on the benzene ring are disordered over two positions; their site-occupation factors were fixed at 0.5. In the crystal, inter­molecular C—H⋯π contacts form infinite chains perpendicular to the b axis. PMID:21578378

  3. Polyimides based on 4,4'-bis (4-aminophenoxy)-2,2'or 2,2', 6,6'-substituted biphenyl

    NASA Technical Reports Server (NTRS)

    Chuang, Chun-Hua K. (Inventor)

    1999-01-01

    This invention relates the novel diamines, the polyimide oligomers and the polyimides derived therefrom and to the method of preparing the diamines, oligomers and the polyimides. The thermoplastic polyimides derived from the aromatic diamines of this invention are characterized as having a high glass transition temperature, good mechanical properties and improved processability in the manufacture of adhesives, electronic and composite materials for use in the automotive and aerospace industry. The distinction of the novel aromatic diamines of this invention is the 2,2',6,6'-substituted biphenyl radicals which exhibit noncoplanar conformation that enhances the solubility of the diamine as well as the processability of the polyimides, while retaining a realatively high glass transition temperature and improved mechanical properties at useful temperature ranges.

  4. Aromatic Diamines and Polyimides Based on 4,4'-Bis-(4-Aminophenoxy)-2,2' or 2,2',6,6'- Substituted Biphenyl

    NASA Technical Reports Server (NTRS)

    Chuang, Chun-Hua K. (Inventor)

    2000-01-01

    This invention relates the novel diamines. the polyimide oligomers and the polyimides derived therefrom and to the method of preparing the diamines, oligomers and the polyimides. The thermoplastic polyimides derived from the aromatic diamines of this invention are characterized as having a high glass transition temperature. good mechanical properties and improved processability in the manufacture of adhesives. electronic and composite materials for use in the automotive and aerospace industry. The distinction of the novel aromatic diamines of this invention is the 2.2',6.6substituted biphenyl radicals which exhibit noncoplanar conformation that enhances the solubility of the diamine as well as the processability of the polyimides. while retaining a relatively high glass transition temperature and improved mechanical properties at useful temperature ranges.

  5. 2,2,6,6-Tetra-bromo-3,4,4,5-tetra-meth-oxy-cyclo-hexa-none.

    PubMed

    Faizi, Md Serajul Haque; Mashrai, Ashraf; Shahid, M

    2014-07-01

    In the title compound, C10H14Br4O5, synthesized from the meth-oxy Schiff base N-(pyridin-2-ylmeth-yl)meth-oxy-aniline and mol-ecular bromine, the cyclo-hexa-none ring has a chair conformation with one of the four meth-oxy groups equatorially orientated with respect to the carbonyl group and the others axially orientated. The C-Br bond lengthsvary from 1.942 (4) to1.964 (4) Å. In the crystal, weak C-H⋯Ocarbon-yl hydrogen-bonding inter-actions generate chains extending along the b-axis direction. Also present in the structure are two short inter-molecular Br⋯Ometh-oxy inter-actions [3.020 (3) and 3.073 (4) Å].

  6. 40 CFR 721.6170 - Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine. 721.6170 Section 721.6170 Protection... Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine... identified as siloxanes and silicones, Me hydrogen, reaction products with...

  7. 40 CFR 721.6170 - Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine. 721.6170 Section 721.6170 Protection... Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine... identified as siloxanes and silicones, Me hydrogen, reaction products with...

  8. 40 CFR 721.6170 - Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine. 721.6170 Section 721.6170 Protection... Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine... identified as siloxanes and silicones, Me hydrogen, reaction products with...

  9. 40 CFR 721.6170 - Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine. 721.6170 Section 721.6170 Protection... Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine... identified as siloxanes and silicones, Me hydrogen, reaction products with...

  10. 40 CFR 721.6170 - Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine. 721.6170 Section 721.6170 Protection... Siloxanes and silicones, Me hydrogen, reaction products with 2,2,6,6-tetramethyl-4-(2-propenyloxy)piperdine... identified as siloxanes and silicones, Me hydrogen, reaction products with...

  11. Direct ab initio study of the C6H6 + CH3/C2H5 = C6H5 + CH4/C2H6 reactions

    NASA Astrophysics Data System (ADS)

    Mai, Tam V.-T.; Ratkiewicz, Artur; Duong, Minh v.; Huynh, Lam K.

    2016-02-01

    A kinetic study of the reactions C6H6 + CH3/C2H5 = C6H5 + CH4/C2H6 was carried out in the temperature range of 300-2500 K using high levels of electronic structure theory, namely, CCSD(T)/CBS//BH&HLYP/cc-pVDZ, and canonical variational transition state theory (CVT) with corrections for small curvature tunneling (SCT) and hindered internal rotation (HIR) treatments. It is found that variational effect is not important and both SCT and HIR corrections noticeably affect the rate constants. Being in good agreement with literature data, the calculated results provide solid basis information for the investigation of the polyaromatic hydrocarbon (PAH) + alkyl radical reaction, an important class in combustion and soot formation.

  12. Coordination polymer based on Cu(II), Co(II) and 4,4'-bipyridine-2,6,2',6'-tetracarboxylate: synthesis, structure and adsorption properties.

    PubMed

    Zhao, Zhou; He, Xiang; Zhao, Yongmei; Shao, Min; Zhu, Shourong

    2009-04-21

    4,4'-Bipyridine-2,6,2',6'-tetracarboxylic acid H4L.3H2O, () and its copper(II) and cobalt (II) coordination polymers [Cu2L(H2O)4]2n () and {[Co(H2O)6].[Co3L2(H2O)2].10H2O}3n () have been hydrothermally synthesized. Compound packs into a crystal via H-bonds. Complex is a 2D coordination grid, in which Cu is in an elongated octahedral constructed by a mer-geometry pyridyl-2,6-dicarboxylate, one bridging carboxylate oxygen and two water molecules. The L4- is central symmetrical. Each pyridyl-2,6-dicarboxylate chelete to Cu(II) and one carboxylate bridge Cu(II) ions in a 1,1-fashion. The 2D coordination polymer links to adjacent layers via H-bonds. Complex is a metal-organic framework with 11.6x10.5 A rectangular channels. All Co(II) ions are located in an octahedral coordination environment. The rectangular channels are composed of Co2+-L4- walls and the walls are linked through carboxylate oxygen atoms and Co(II) ions. Co(H2O)6(2+) as counter ions fill in porous channel. The removal of water molecules from at 210 degrees C or higher affords the porous material [Co4L2]n, which can adsorb 16 (36%) methanol or 9 (32%) ethanol in the vapour phase. The porosity of is higher than reported 4,4'-bipyridine-2,6,2',6'- tetracarboxylate complexes. The framework of remains but the crystallinity is lost upon removal of the H2O molecules. The dehydrated framework of partially recovery crystallinity after it adsorbs H2O, CH3OH and C2H5OH. The methanol in the framework can be replaced by H2O reversibly.

  13. 1,1'-Fc(4-C6H4CO2Et)2 and its unusual salt derivative with Z' = 5, catena-[Na+]2[1,1'-Fc(4-C6H4CO2-)2].0.6H2O [1,1'-Fc = (eta5-(C5H4)2Fe].

    PubMed

    Gallagher, John F; Alley, Steven; Brosnan, Marianne; Lough, Alan J

    2010-04-01

    The neutral diethyl 4,4'-(ferrocene-1,1'-diyl)dibenzoate, Fe[eta(5)-(C(5)H(4))(4-C(6)H(4)CO(2)Et)](2) (I), yields (II) (following base hydrolysis) as the unusual complex salt poly[disodium bis[diethyl 4,4'-(ferrocene-1,1'-diyl)dibenzoate] 0.6-hydrate] or [Na(+)](2)[Fe{eta(5)-(C(5)H(4))-4-C(6)H(4)CO(2)(-)}(2)].0.6H(2)O with Z' = 5. Compound (I) crystallizes in the triclinic system, space group P1, with two molecules having similar geometry in the asymmetric unit (Z' = 2). The salt complex (II) crystallizes in the orthorhombic system, space group Pbca, with the asymmetric unit comprising poly[decasodium pentakis[diethyl 4,4'-(ferrocene-1,1'-diyl)dibenzoate] trihydrate] or [Na(+)](10)[Fe{eta(5)-(C(5)H(4))-4-C(6)H(4)CO(2)(-)}(2)](5).3H(2)O. The five independent 1,1'-Fc[(4-C(6)H(4)CO(2))(-)](2) dianions stack in an offset ladder (stepped) arrangement with the ten benzoates mutually oriented cisoid towards and bonded to a central layer comprising the ten Na(+) ions and three water molecules [1,1'-Fc = eta(5)-(C(5)H(4))(2)Fe]. The five dianions differ in the cisoid orientations of their pendant benzoate groups, with four having their -C(6)H(4)- groups mutually oriented at interplanar angles from 0.6 (3) to 3.2 (3) degrees (as pi...pi stacked C(6) rings) and interacting principally with Na(+) ions. The fifth dianion is distorted and opens up to an unprecedented -C(6)H(4)- interplanar angle of 18.6 (3) degrees through bending of the two 4-C(6)H(4)CO(2) groups and with several ionic interactions involving the three water molecules (arranged as one-dimensional zigzag chains in the lattice). Overall packing comprises two-dimensional layers of Na(+) cations coordinated mainly by the carboxylate O atoms, and one-dimensional water chains. The non-polar Fc(C(6)H(4))(2) groups are arranged perpendicular to the layers and mutually interlock through a series of efficient C-H...pi stacking contacts in a herringbone fashion to produce an overall segregation of polar and non

  14. 2,6-Di-amino-4-chloro-pyrimidinium 4-carb-oxy-butano-ate.

    PubMed

    Edison, Bellarmin; Balasubramani, Kasthuri; Thanigaimani, Kaliyaperumal; Khalib, Nuridayanti Che; Arshad, Suhana; Razak, Ibrahim Abdul

    2014-08-01

    In the title mol-ecular salt, C4H6ClN4 (+)·C5H7O4 (-), the cation is essentially planar, with a maximum deviation of 0.037 (1) Å for all non-H atoms. The anions are self-assembled through O-H⋯O hydrogen bonds, forming a supra-molecular zigzag chain with graph-set notation C(8). In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds with an R 2 (2)(8) ring motif. This motif further self-organizes through N-H⋯O and O-H⋯O hydrogen bonds, generating an array of six hydrogen bonds, the rings having graph-set notation R 3 (2)(8), R 2 (2)(8), R 4 (2)(8), R 2 (2)(8) and R 3 (2)(8). In addition, another type of R 2 (2)(8) motif is formed by inversion-related pyrimidinium cations via N-H⋯N hydrogen bonds, forming a two-dimensional network parallel to (101).

  15. 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4',6''-dibenzo[d,f][1,3,2]dioxaphosphepine-6',6'''-dibenzo[d,f][1,3,2]dioxaphosphepine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The title compound 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4',6''-dibenzo[d,f][1,3,2]dioxaphosphepine-6',6'''-dibenzo[d,f][1,3,2]dioxaphosphepine], C26H22N5O4P3, at 100°K has monoclinic (P21/c) symmetry and is achieved in a two step synthesis that does...

  16. Ligand substituent effect observed for ytterbocene 4'-cyano-2,2':6',2' '-terpyridine.

    PubMed

    Veauthier, Jacqueline M; Schelter, Eric J; Kuehl, Christopher J; Clark, Aurora E; Scott, Brian L; Morris, David E; Martin, Richard L; Thompson, J D; Kiplinger, Jaqueline L; John, Kevin D

    2005-08-08

    A new N-heterocyclic complex of ytterbocene (Cp(2)Yb(II), Cp = C(5)Me(5)) has been prepared by the addition of 4'-cyano-2,2':6',2' '-terpyridine (tpyCN) to Cp(2)Yb(II)(OEt(2)) in toluene to give a dark blue species designated as Cp(2)Yb(tpyCN). The effect of the electron-withdrawing group (-CN) on the redox potentials of the charge-transfer form of this complex [in which an electron is transferred from the f(14) metal center to the lowest unoccupied (pi) molecular orbital of the tpyCN ligand to give a 4f(13)-pi(1) electronic configuration] has been quantified by cyclic voltammetry. The tpyCN ligand stabilizes this configuration by 60 mV more than that in the unsubstituted tpy ligand complex and by 110 mV more than that in the unsubstituted bpy ligand complex. Magnetic susceptibility measurements corroborate the enhanced stabilization of the 4f(13)-pi(1) configuration by the substituted terpyridyl ligand complex. Furthermore, the temperature dependence of the magnetic data is most consistent with a thermally induced valence tautomeric equilibrium between this paramagnetic 4f(13)-pi(1) form that dominates near room temperature and the diamagnetic 4f(14)-pi(0) form that dominates at low temperature. Differing coordination modes for the tpyCN ligand to the ytterbocene center have also been confirmed by isolation and X-ray crystallographic characterization of complexes binding through either the cyano nitrogen of tpyCN or the three terpyridyl nitrogen atoms of tpyCN.

  17. pH-dependent aquatic criteria for 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol.

    PubMed

    Xing, Liqun; Liu, Hongling; Giesy, John P; Yu, Hongxia

    2012-12-15

    Due to their agricultural as well as industrial uses, 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) are ubiquitous in the environment and recognized as priority pollutants in many countries. In this study, effects of pH on toxicity to the crustacean Daphnia magna and the alga Scenedesmus obliquus were investigated. Combined published toxicity data of the three chlorophenols along with; relationships between toxicity and pH reported here were used to establish pH-dependent water quality criteria (WQC). The WQC expressed as a function of pH, also considered intra-species variation and proportions of taxonomic groups. At pH 7.8, the recommended acute exposure water quality criteria (WQC) were 286.2 μg 2,4-DCP/l, 341.5 μg 2,4,6-TCP/l and 11.4 μg PCP/l. The recommended chronic exposure WQC were 16.3 μg 2,4-DCP/l, 54.6 μg 2,4,6-TCP/land 3.9 μg PCP/l.

  18. A copper–polyol complex: [Na2(C2H6O2)6][Cu(C2H4O2)2

    PubMed Central

    Rivers, Joseph H.; Carroll, Kyler J.; Jones, Richard A.; Carpenter, Everett E.

    2010-01-01

    The ionic title complex, bis(μ-ethyl­ene glycol)-κ3 O,O′:O′;κ3 O:O,O′-bis[(ethyl­ene glycol-κ2 O,O′)(ethyl­ene glycol-κO)sodium] bis(ethyl­ene glycolato-κ2 O,O′)copper(II), [Na2(C2H6O2)6][Cu(C2H4O2)2], was obtained from a basic solution of CuCl2 in ethyl­ene glycol and consists of discrete ions inter­connected by O—H⋯O hydrogen bonds. This is the first example of a disodium–ethyl­ene glycol complex cation cluster. The cation lies about an inversion center and the CuII atom of the anion lies on another independent inversion center. PMID:20203401

  19. Synthesis, Molecular Structure, and Reactivity of the Tetranuclear Complex [NBu(4)](2)[Pd(4)(&mgr;-PPh(2))(2)(&mgr;-Cl)(4)(C(6)F(5))(4)]. Molecular Structure of [Pd(2)(&mgr;-PPh(2))(C(6)F(5))(2)(bipy)(2)]ClO(4).C(6)H(14).

    PubMed

    Alonso, Ester; Forniés, Juan; Fortuño, Consuelo; Martín, Antonio; Rosair, Georgina M.; Welch, Alan J.

    1997-09-24

    Anionic tetranuclear complexes with the molecular formula [NBu(4)](2)[Pd(4)(&mgr;-PPh(2))(2)(&mgr;-X)(4)(C(6)F(5))(4)] [X = Cl (1), Br (2)] were obtained by reaction of [NBu(4)](2)[Pd(2)(&mgr;-PPh(2))(2)(C(6)F(5))(4)] and PdCl(2) (or K(2)[PdCl(4)]) in acetone, followed by reaction with KBr for 2. The reactions of 1 with neutral monodentate (L) or bidentate (L-L) ligands afford the dinuclear derivatives [Pd(2)(&mgr;-PPh(2))(&mgr;-Cl)(C(6)F(5))(2)L(2)] [L = PPh(3) (3), py (4)] or [Pd(2)(&mgr;-PPh(2))(C(6)F(5))(2)(L-L)(2)](n)() [n = 1-, L-L = acac (6); n = 1+, L-L = bipy (7) or phen (8)]. The structures of complexes 1 and 7 were determined by single-crystal X-ray diffraction studies. The bis(acetone) solvate of complex 1, [NBu(4)](2)[Pd(4)(&mgr;-PPh(2))(2)(&mgr;-Cl)(4)(C(6)F(5))(4)].2C(3)H(6)O, crystallizes in the monoclinic system, space group P2(1)/c, with a = 11.679(5) Å, b = 16.552(7) Å, c = 23.868(8) Å, beta = 101.10(3) degrees, V = 4527.6(15) Å(3), and Z = 2. The central core of the anion has the shape of a rectangle with the four Pd atoms in the corners. The hexane solvate of complex 7, [Pd(2)(&mgr;-PPh(2))(C(6)F(5))(2)(bipy)(2)][ClO(4)].C(6)H(14), crystallizes in the monoclinic system, space group P2(1)/n, with a = 16.214(3) Å, b = 10.311(2) Å, c = 28.380(6) Å, beta = 100.82(3) degrees, V = 4660(2) Å(3), and Z = 4. In both complexes, the long Pd.Pd distances (>3.1 Å) clearly point to the absence of any Pd-Pd interaction.

  20. Coordination polymers and metal-organic frameworks derived from 4,4'-dicarboxy-2,2'-bipyridine and 4,4',6,6'-tetracarboxy-2,2'-bipyridine ligands: a personal perspective.

    PubMed

    Kruger, Paul E

    2013-01-01

    Presented herein is a personal overview of some of the contributions we have made over recent years to coordination polymer chemistry employing 2,2'-bipyridine-polycarboxylic acid ligands in conjunction with first row transition, main group or lanthanide metal ions. Primarily the discussion is centred upon the two ligands with which we have enjoyed the most success: 4,4'-dicarboxy-2,2'-bipyridine (4,4'-H2dcbp) and 4,4',6,6'-tetracarboxy-2,2'-bipyridine (4,4',6,6'-H4tcbp). Initial discussion is focused upon the synthetic aspects of ligand formation and their structural characterisation and then moves on to the synthesis of metal complexes incorporating these ligands and the coordination polymers they form. Where possible the discussion is presented from a synthetic and structural perspective with highlight given to the pertinent properties of the coordination polymers formed e.g. thermal behaviour, magnetic, luminescent or small molecule sorption properties. We end the review with some conclusions and highlight some current work with a view to future research.

  1. Dynamically Complex [6+4] and [4+2] Cycloadditions in the Biosynthesis of Spinosyn A

    PubMed Central

    Patel, Ashay; Chen, Zhuo; Yang, Zhongyue; Gutiérrez, Osvaldo; Liu, Hung-wen; Houk, K. N.; Singleton, Daniel A.

    2017-01-01

    SpnF, an enzyme involved in the biosynthesis of spinosyn A, catalyzes a transannular Diels–Alder reaction. Quantum mechanical computations and dynamic simulations now show that this cycloaddition is not well described as either a concerted or stepwise process, and dynamical effects influence the identity and timing of bond formation. The transition state for the reaction is ambimodal and leads directly to both the observed Diels–Alder and an unobserved [6+4] cycloadduct. The potential energy surface bifurcates and the cycloadditions occur by dynamically stepwise modes featuring an “entropic intermediate”. A rapid Cope rearrangement converts the [6+4] adduct into the observed [4+2] adduct. Control of nonstatistical dynamical effects may serve as another way by which enzymes control reactions. PMID:26909570

  2. Mixed triorganobismuthines RAr2Bi [Ar = C6F5, 2,4,6-(C6F5)3C6H2] and hypervalent racemic Bi-chiral diorganobismuth(iii) bromides RArBiBr (Ar = C6F5, Mes, Ph) with the ligand R = 2-(Me2NCH2)C6H4. Influences of the organic substituent.

    PubMed

    Olaru, Marian; Nema, Mihai G; Soran, Albert; Breunig, Hans J; Silvestru, Cristian

    2016-06-21

    Triorganobismuthines R(C6F5)2Bi (1) and R[2,4,6-(C6F5)3C6H2]2Bi (2) [R = 2-(Me2NCH2)C6H4] were synthesized by reaction of RBiBr2 with C6F5MgBr and 2,4,6-(C6F5)3C6H2Li, respectively, in a 1 : 2 molar ratio. The Bi-chiral bromides R(C6F5)BiBr (3), R(Mes)BiBr (4), and R(Ph)BiBr (5) were obtained from RBiBr2 and C6F5MgBr, MesMgBr or PhMgBr, or from PhBiBr2 and RLi, in a 1 : 1 molar ratio. The molecular structures of 1-5 were determined by single-crystal X-ray diffraction and are discussed taking into account the chirality of the species. Supramolecular aspects in the solid state are presented. The solution behaviour of the title compounds, including dynamic aspects, are discussed on the basis of multinuclear ((1)H, (13)C, (19)F) NMR spectroscopy.

  3. Ultrasonically assisted turning of Ti-6Al-2Sn-4Zr-6Mo

    NASA Astrophysics Data System (ADS)

    Muhammad, R.; Maurotto, A.; Roy, A.; Silberschmidt, V. V.

    2012-08-01

    Titanium alloys are widely used in the aerospace and offshore industries due to their high strength-to-weight ratio sustained at elevated temperatures, their fracture-resistance features and exceptionally good corrosion-resistance properties. However, poor thermal conductivity and high chemical affinity of these alloys to tool materials severely impair their machinability. As a result the machining processes of titanium alloys are typically characterized by low cutting feeds and speeds making production of components uneconomical. Recently, a non-conventional hybrid machining technique, namely, ultrasonically assisted turning has been shown to significantly improve the machinability of intractable alloys with a concomitant improvement in material removal rates, thus improving machining economics. In the current work, a 3D finite element model of turning of Ti-6Al-2Sn-4Zr-6Mo is developed in the commercial software, MSC Marc/Mentat. A constitutive behaviour of the workpiece material under large deformations and elevated temperatures is adequately represented by a Johnson-Cook material model. For validation of the developed numerical model, experimental tests were carried out. The numerical and experimental results were found to be in good agreement.

  4. Organically templated uranium(IV) fluorooxalates with layer structures: (H4TREN)[U2F6(C2O4)3].4H2O (TREN = tris(2-aminoethyl)amine) and (H4APPIP)[U2F6(C2O4)3].4H2O (APPIP = 1,4-bis(3-amino-propyl)piperazine).

    PubMed

    Wang, Chih-Min; Wu, Yi-Ying; Chen, Pei-Lin; Lii, Kwang-Hwa

    2007-03-14

    Two organically-templated layered uranium(IV) fluorooxalates, (H(4)TREN)[U(2)F(6)(C(2)O(4))(3)].4H(2)O (1) (TREN = tris(2-aminoethyl)amine) and (H(4)APPIP)[U(2)F(6)(C(2)O(4))(3)].4H(2)O (2) (APPIP = 1,4-bis(3-aminopropyl)piperazine), have been synthesized by hydrothermal methods and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and magnetic susceptibility. Both structures consist of anionic [U(2)F(6)(C(2)O(4))(3)](4-) layers separated by organic ammonium cations and lattice water molecules. The UF(3)O(6) polyhedra are connected by oxalate ligands in different ways within the layers. They are the first examples of organically-templated uranium fluorooxalates. Crystal data for compound 1 follow: monoclinic, P2(1)/c (No. 14), a = 19.1563(5) A, b = 8.9531(2) A, c = 16.6221(4) A, beta = 114.633(1) degrees, and Z = 4. Crystal data for compound are the same as those for 1 except a = 10.3309(8) A, b = 15.564(1) A, c = 17.537(1) A, and beta = 95.430(4) degrees.

  5. Destruction of 2,4,6-trinitrotoluene using ammonium peroxydisulfate

    SciTech Connect

    Cooper, J.F.; Wang, F.; Shell, T.; King, K.

    1996-07-01

    TNT was destroyed in a small batch reactor, using uncatalyzed 4 N ammonium peroxydisulfate at 95 {degrees}C. The material was destroyed below limit of detection in less that 15 minutes, indicating a formal order rate constant of 0.06 min{sup -1}. A crude estimate of scaleup rates indicates a throughput of 1 tonne/m{sup 3}-day.

  6. Photophysical Properties of 4'-(p-aminophenyl)-2,2':6',2″-terpyridine

    NASA Astrophysics Data System (ADS)

    Song, Peng; Sun, Shi-guo; Zhou, Pan-wang; Liu, Jian-yong; Xu, Yong-qian; Peng, Xiao-jun

    2010-10-01

    Spectral and photophysical investigations of 4'-(p-aminophenyl)-2,2':6',2″-terpyridine (APT) have been performed in various solvents with different polarity and hydrogen-bonding ability. The emission spectra of APT are found to exhibit dual fluorescence in polar solvents, which attributes to the local excited and intramolecular charge transfer states, respectively. The two-state model is proven out for APT in polar solvent by the time-correlated single photon counting emission decay measurement. Interestingly, the linear relationships of different emission maxima and solvent polarity parameter are found for APT in protic and aprotic solvents, because of the hydrogen bond formation between APT and alcohols at the amino nitrogen N25. Furthermore, the effects of the complexation of the metal ion with tpy group of APT and the hydrogen bond formation between APT with methanol at the terpyridine nitrogen N4-N8-N14 are also presented. The appearance of new long-wave absorption and fluorescence bands indicates that a new ground state of the complexes is formed.

  7. Crystal structures of ethyl 6-(4-methyl-phen-yl)-4-oxo-4H-chromene-2-carboxyl-ate and ethyl 6-(4-fluoro-phen-yl)-4-oxo-4H-chromene-2-carboxyl-ate.

    PubMed

    Gomes, Ligia R; Low, John Nicolson; Fernandes, Carlos; Gaspar, Alexandra; Borges, Fernanda

    2016-01-01

    The crystal structures of two chromone derivatives, viz. ethyl 6-(4-methyl-phen-yl)-4-oxo-4H-chromene-2-carboxyl-ate, C19H16O4, (1), and ethyl 6-(4-fluoro-phen-yl)-4-oxo-4H-chromene-2-carboxyl-ate C18H13FO4, (2), have been determined: (1) crystallizes with two mol-ecules in the asymmetric unit. A comparison of the dihedral angles beween the mean planes of the central chromone core with those of the substituents, an ethyl ester moiety at the 2-position and a para-substituted phenyl ring at the 6-position shows that each mol-ecule differs significantly from the others, even the two independent mol-ecules (a and b) of (1). In all three mol-ecules, the carbonyl groups of the chromone and the carboxyl-ate are trans-related. The supra-molecular structure of (1) involves only weak C-H⋯π inter-actions between H atoms of the substituent phenyl group and the phenyl group, which link mol-ecules into a chain of alternating mol-ecules a and b, and weak π-π stacking inter-actions between the chromone units. The packing in (2) involves C-H⋯O inter-actions, which form a network of two inter-secting ladders involving the carbonyl atom of the carboxyl-ate group as the acceptor for H atoms at the 7-position of the chromone ring and from an ortho-H atom of the exocyclic benzene ring. The carbonyl atom of the chromone acts as an acceptor from a meta-H atom of the exocyclic benzene ring. π-π inter-actions stack the mol-ecules by unit translation along the a axis.

  8. catena-Poly[{μ(3)-4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanyl-yl-idene)]diphenolato}{μ(2)-4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]diphenolato}dicopper(II)].

    PubMed

    Kia, Reza; Kargar, Hadi; Adabi Ardakani, Amir; Tahir, Muhammad Nawaz

    2012-07-01

    The asymmetric unit of the title compound, [Cu(2)(C(18)H(14)Cl(4)N(2)O(2))(2)](n), contains two independent Cu(II) ions which are bridged by a pair of 4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]diphenolate ligands, forming a dinuclear unit. One of the Cu(II) ions is coordinated in a distorted square-planar environment and the other is coordinated in a distorted square-pyramidal environment. The long apical Cu-O bond of the square-pyramidal coordinated Cu(II) ion is formed by a symmetry-related O atom, creating a one-dimensional polymer along [010]. In addition, short inter-molecular Cl⋯Cl distances [3.444 (2) Å] and weak π-π inter-actions [centroid-centroid distances = 3.736 (2)-3.875 (3) Å] are observed. The crystal studied was an inversion twin with a refined twin component ratio of 0.60 (1):0.40 (1).

  9. Antiinflammatory 2,6-di-tert-butyl-4-(2-arylethenyl)phenols.

    PubMed

    Lazer, E S; Wong, H C; Possanza, G J; Graham, A G; Farina, P R

    1989-01-01

    A series of 2,6-di-tert-butyl-4-(2-arylethenyl)phenols was prepared and examined for their ability to inhibit cyclooxygenase and 5-lipoxygenase in vitro and developing adjuvant arthritis in vivo in the rat. Structure-activity relationships are discussed. Among the best compounds is (E)-2,6-di-tert-butyl-4-[2-(3-pyridinyl)ethenyl]phenol (7d). It has an IC50 of 0.67 microM for cyclooxygenase and 2.7 microM for 5-lipoxygenase and an ED50 of 2.1 mg/kg in developing adjuvant arthritis. Additional in vivo data are reported for 7d.

  10. Synthesis, spectral, thermal, optical and theoretical studies of (2E,6E)-2-benzylidene-6-(4-methoxybenzylidene)cyclohexanone.

    PubMed

    Meenatchi, V; Muthu, K; Rajasekar, M; Meenakshisundaram, Sp

    2014-01-01

    Single crystals of (2E,6E)-2-benzylidine-6-(4-methoxybenzylidine)cyclohexanone are grown by slow evaporation of ethanolic solution at room temperature. The characteristic functional groups present in the molecule are confirmed by Fourier transform infrared and Fourier transform Raman analyses. The scanning electron microscopy study reveals the surface morphology of the material. Thermogravimetric/differential thermal analysis study reveals the purity of the material and the crystal is transparent in the visible region having a lower optical cut-off at ∼487nm. The second harmonic generation efficiency of as-grown material is estimated by Kurtz and Perry technique. Optimized geometry has been derived using Hartree-Fock calculations performed at the level 6-31G (d,p) and the first-order molecular hyperpolarizability (β) is estimated. The specimen is further characterized by nuclear magnetic resonance spectroscopy.

  11. Synthesis and Antimicrobial Activity of 6-Thioxo-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]-quinazolin-2-one Derivatives

    PubMed Central

    Nosulenko, Inna S.; Voskoboynik, Olexii Yu.; Berest, Galina G.; Safronyuk, Sergiy L.; Kovalenko, Sergiy I.; Kamyshnyi, Oleksandr M.; Polishchuk, Nataliya M.; Sinyak, Raisa S.; Katsev, Andrey V.

    2014-01-01

    Abstract Potassium 8-R1-9-R2-10-R3-3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-6-thiolates 2.1–2.26 were synthesized via cyclocondensation of 6-R-3-(3-R1-4-R2-5-R3-aminophenyl)-1,2,4-triazin-5-ones 1.1–1.26 with carbon disulfide, potassium hydroxide, and ethanol or with potassium O-ethyl dithiocarbonate in 2-propanol. The corresponding thiones 3.1–3.26 were obtained by treatment of 2.1–2.26 with hydrochloric acid. It was found that the nature of the substituents in positions 3, 4, and 5 of the corresponding 6-R-3-(3-R1-4-R2-5-R3-aminophenyl)-1,2,4-triazin-5-ones were affected on the terms of the reaction. The structures of compounds were proven by a complex of physicochemical methods (1H, 13C NMR, LC–MS, and EI-MS). The results of the antibacterial and antifungal activity assay allowed the determination of the high sensitivity of Staphylococcus aureus ATCC 25923 (MIC 6.25–100 μg/mL, MBC 12.5–200 μg/mL) to the synthesized compounds. PMID:25853063

  12. 40 CFR 721.5740 - Phenol, 4,4′-methy-lenebis (2,6-dimethyl-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol, 4,4â²-methy-lenebis (2,6... Specific Chemical Substances § 721.5740 Phenol, 4,4′-methy-lenebis (2,6-dimethyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as Phenol,...

  13. Thymine photodimer formation in DNA hairpins. Unusual conformations favor (6 - 4) vs. (2 + 2) adducts.

    PubMed

    Hariharan, Mahesh; Siegmund, Karsten; Saurel, Clifton; McCullagh, Martin; Schatz, George C; Lewis, Frederick D

    2014-02-01

    The photochemical reactions of eleven synthetic DNA hairpins possessing a single TT step either in a base-paired stem or in a hexanucleotide linker have been investigated. The major reaction products have been identified as the cis-syn (2 + 2) adduct and the (6 - 4) adduct on the basis of their spectroscopic properties including 1D and 2D NMR spectra, UV spectra and stability or instability to photochemical cleavage. Product quantum yields and ratios determined by HPLC analysis allow the behaviour of the eleven hairpins to be placed into three groups: Group I in which the (2 + 2) adduct is the major product, as is usually the case for DNA, Group II in which comparable amounts of (2 + 2) and (6 - 4) adducts are formed, and Group III in which the major product is the (6 - 4) adduct. The latter behaviour is without precedent in natural or synthetic DNA and appears to be related to the highly fluxional structures of the hairpin reactants. Molecular dynamics simulation of ground state conformations provides quantum yields and product ratios calculated using a single parameter model that are in reasonable agreement with most of the experimental results. Factors which may influence the observed product ratios are discussed.

  14. Thermophysical properties of CF4/O2 and SF6/O2 gas mixtures

    NASA Astrophysics Data System (ADS)

    Damyanova, M.; Hohm, U.; Balabanova, E.; Barton, D.

    2016-03-01

    Fitting formulae are presented for the calculation of the second interaction virial coefficients, mixture viscosities and binary diffusion coefficients for CF4/O2 and SF6/O2 gas mixtures in the temperature range between 200 K and 1000 K. The data recommended are obtained from the isotropic (n-6) Lennard-Jones intermolecular interaction potentials of the pure substances by using the Hohm-Zarkova-Damyanova mixing rules. In general, a good agreement is observed between our results and the experimental and theoretical data found in the literature.

  15. (Z)-Ethyl 3-(2,4,6-trimethyl­anilino)but-2-enoate

    PubMed Central

    Amézquita-Valencia, Manuel; Hernández-Ortega, Simón; Suárez-Ortiz, G. Alejandra; Toscano, Rubén Alfredo; Cabrera, Armando

    2009-01-01

    The title compound, C15H21NO2, was obtained by the reaction of acetoacetate with 2,4,6-trimethyl­aniline using Mexican bentonitic clay as a catalyst. It crystallizes in the enamine form. The β-enamino ester residue is almost perpendicular to the aromatic ring [dihedral angle = 88.10 (6)°]. The mol­ecular conformation is stabilized by a strong intra­molecular N—H⋯O hydrogen bond. In addition, the N—H group forms a weak inter­molecular N—H⋯O hydrogen bond linking the mol­ecules into centrosymmetric dimers. PMID:21578324

  16. Reduction of 2,4,6-trinitrotoluene by Clostridium acetobutylicum through hydroxylamino-nitrotoluene intermediates

    SciTech Connect

    Hughes, J.B.; Wang, C.Y.; Bhadra, R.; Richardson, A.; Bennett, G.N.; Rudolph, F.B.

    1998-03-01

    Studies were conducted to isolate and identify intermediates of 2,4,6-trinitrotoluene (TNT) transformation by Clostridium acetobutylicum and to quantify their concentrations in active whole cell cultures. Only two intermediates of TNT reduction were detected in cell cultures and were identified as 4-hydroxylamino-2,6-dinitrotoluene and 2,4-dihydroxylamino-6-nitrotoluene. Structures were confirmed with {sup 1}H-NMR, {sup 13}C-NMR, and desorption chemical ionization mass spectroscopy. When cells were suspended in a non-growth saline medium, both hydroxylamine forms accumulated. In media capable of supporting cell growth, the 2,4-dihydroxylamino-6-nitrotoluene accumulated with concentrations of 4-hydroxylamino-2,6-dinitrotoluene remaining near detection limits. Studies using purified 2,4-dihydroxylamino-6-nitrotoluene confirmed that its biotransformation rate in active cultures greatly exceeded abiotic decomposition in aqueous medium.

  17. Vibrational spectra of Cs2Cu(SO4)2·6H2O and Cs2Cu(SeO4)2·nH2O (n = 4, 6) with a crystal structure determination of the Tutton salt Cs2Cu(SeO4)2·6H2O

    NASA Astrophysics Data System (ADS)

    Wildner, M.; Marinova, D.; Stoilova, D.

    2016-02-01

    The solubility in the three-component systems Cs2SO4-CuSO4-H2O and Cs2SeO4-CuSeO4-H2O have been studied at 25 °C. The experimental results show that double salts, Cs2Cu(SO4)2·6H2O and Cs2Cu(SeO4)2·4H2O, crystallize from the ternary solutions within large concentration ranges. Crystals of Cs2Cu(SeO4)2·6H2O were synthesized at somewhat lower temperatures (7-8 °C). The thermal dehydration of the title compounds was studied by TG, DTA and DSC methods and the respective dehydration schemes are proposed. The calculated enthalpies of dehydration (ΔHdeh) have values of: 434.2 kJ mol-1 (Cs2Cu(SeO4)2·6H2O), 280.9 kJ mol-1 (Cs2Cu(SeO4)2·4H2O), and 420.2 kJ mol-1 (the phase transition of Cs2Cu(SO4)2·6H2O into Cs2Cu(SO4)2·H2O). The crystal structure of Cs2Cu(SeO4)26H2O was determined from single crystal X-ray diffraction data. It belongs to the group of Tutton salts, crystallizing isotypic to the respective sulfate in a monoclinic structure which is characterized by isolated Cu(H2O)6 octahedra and SeO4 tetrahedra, interlinked by hydrogen bonds and [9]-coordinated Cs+ cations. Infrared spectra of the cesium copper compounds are presented and discussed with respect to both the normal modes of the tetrahedral ions and the water molecules. The analysis of the infrared spectra of the double compounds reveals that the distortion of the selenate tetrahedra in Cs2Cu(SeO4)2·4H2O is stronger than those in Cs2Cu(SeO4)2·6H2O in agreement with the structural data. Matrix-infrared spectroscopy was applied to confirm this claim - Δν3 for SO4 2 - ions matrix-isolated in Cs2Cu(SeO4)2·6H2O has a value of 35 cm-1 and that of the same ions included in Cs2Cu(SeO4)2·4H2O - 84 cm-1. This spectroscopic finding is due to the formation of strong covalent bands Cu-OSO3 on one hand, and on the other to the stronger deformation of the host SeO4 2 - tetrahedra in Cs2Cu(SeO4)2·4H2O as compared to those in Cs2Cu(SeO4)2·6H2O. The strength of the hydrogen bonds as deduced from the

  18. 2,2,4,4,5,5-Hexakis(2,6-Diethylphenyl) pentastanna (1.1.1)Propellane: Characterization and Molecular Structure

    DTIC Science & Technology

    1989-05-24

    Thermolysis of hexakis(2,6-diethylphenyl)cyclotristannane in xylenes at 2 0 0d’C provides blue violet, crystalline 2 ,2 ,4 ,4 ,5,5-hexakis(2,6...and a structure with substantial singlet diradical character is proposed for 1. Solutions of 1 are intensely blue -violet in color with abscrption maxima...University Pittsburgh, PA 15213 Thermolysis of hexakis(2,6-diethylphenyl)cyclotristannane, 4, in xylenes at 200 0 C provides blue violet, crystalline

  19. Luminescent nitridophosphates CaP2 N4 :Eu(2+) , SrP2 N4 :Eu(2+) , BaP2 N4 :Eu(2+) , and BaSr2 P6 N12 :Eu(2.).

    PubMed

    Pucher, Florian J; Marchuk, Alexey; Schmidt, Peter J; Wiechert, Detlef; Schnick, Wolfgang

    2015-04-20

    Nitridophosphates MP2 N4 :Eu(2+) (M=Ca, Sr, Ba) and BaSr2 P6 N12 :Eu(2+) have been synthesized at elevated pressures and 1100-1300 °C starting from the corresponding azides and P3 N5 with EuCl2 as dopant. Addition of NH4 Cl as mineralizer allowed for the growth of single crystals. This led to the successful structure elucidation of a highly condensed nitridophosphate from single-crystal X-ray diffraction data (CaP2 N4 :Eu(2+) (P63 , no. 173), a=16.847(2), c=7.8592(16) Å, V=1931.7(6) Å(3) , Z=24, 2033 observed reflections, 176 refined parameters, wR2 =0.096). Upon excitation by UV light, luminescence due to parity-allowed 4f(6) ((7) F)5d(1) →4f(7) ((8) S7/2 ) transition was observed in the orange (CaP2 N4 :Eu(2+) , λmax =575 nm), green (SrP2 N4 :Eu(2+) , λmax =529 nm), and blue regions of the visible spectrum (BaSr2 P6 N12 :Eu(2+) and BaP2 N4 :Eu(2+) , λmax =450 and 460 nm, respectively). Thus, the emission wavelength decreases with increasing ionic radius of the alkaline-earth ions. The corresponding full width at half maximum values (2240-2460 cm(-1) ) are comparable to those of other known Eu(2+) -doped (oxo)nitrides emitting in the same region of the visible spectrum. Following recently described quaternary Ba3 P5 N10 Br:Eu(2+) , this investigation represents the first report on the luminescence of Eu(2+) -doped ternary nitridophosphates. Similarly to nitridosilicates and related oxonitrides, Eu(2+) -doped nitridophosphates may have the potential to be further developed into efficient light-emitting diode phosphors.

  20. Penta- and 2,4,6-tri-chlorophenol biodegradation during municipal solid waste anaerobic digestion.

    PubMed

    Limam, Intissar; Limam, Rim Driss; Mezni, Mohamed; Guenne, Angéline; Madigou, Céline; Driss, Mohamed Ridha; Bouchez, Théodore; Mazeas, Laurent

    2016-08-01

    In this study isotopic tracing using (13)C labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35°C (mesophilic) and 55°C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, (13)C6-PCP and (13)C6-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35°C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance ((13)C-NMR) Spectroscopy analysis of (13)C labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35°C to acetate and then to HCO(3-). Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of (13)C labelled 2,4,6-TCP into (13)C (CH4 and CO2). Concerning (13)C labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no dechlorination was observed at 55°C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions.

  1. Fluorescent complexes of DNA with DAPI 4′,6-diamidine-2-phenyl indole.2HCl or DCI 4′,6-dicarboxyamide-2-phenyl indole

    PubMed Central

    Kapuściński, Jan; Skoczylas, Bogna

    1978-01-01

    4′,6-Dioarboxyamide-2-phenyl indole (DCI), a non-ionic structural analogue of 4′,6-diamidine-2-phenyl indole·2HCl (DAPI), was synthesized in order to verify the hypothesis of intercalation of both dyes into the DNA double helix. The influence of pH, viscosity, and different concentrations of SDS (sodium dodecylsulphate) or NaCl on the optical and fluorescent properties and the changes in thermal transition of both dye complexes with DNA confirm the affinity of the dyes to the double helix as well as their stabilizing influence on the secondary DNA structure. The results of binding studies, carried out by fluorescent methods have shown that the dyes are strongly bound to DNA, though the number of binding sites is small. According to the experimental data, the fluorescent properties of DAPI and DCI complexes with DNA are connected with the intercalating binding mechanism of these dyes. On the other hand, the eventual ionic or hydrogen bonds of dyes outside the DNA helix do not change noticeably their fluorescent properties. PMID:31603

  2. Optical spectroscopy of ZnSiF6·6H2O:Mn4+ red phosphor

    NASA Astrophysics Data System (ADS)

    Hoshino, Ryosuke; Adachi, Sadao

    2013-12-01

    We report on a method of synthesizing Mn4+-activated ZnSiF6.6H2O hydrate phosphor by the chemical reaction in a Teflon beaker. The structural and optical properties of ZnSiF6.6H2O:Mn4+ are investigated using x-ray diffraction measurement, photoluminescence (PL) analysis, PL excitation spectroscopy, diffuse reflectance measurement, and Raman scattering spectroscopy. The synthesized phosphor exhibits a series of sharp red emission peaks at ˜630 nm, which is characteristic for Mn4+ ions. The luminescent study is focused on the thermal quenching phenomenon above ˜300 K and is found to be caused by thermal decomposition of the ZnSiF6.6H2O host. Degradation in the PL intensity under near-UV light illumination has also been observed to occur in this phosphor.

  3. Transfer between the cesium 6 {sup 2}P{sub 1/2} and 6 {sup 2}P{sub 3/2} levels induced by collisions with H{sub 2}, HD, D{sub 2}, CH{sub 4}, C{sub 2}H{sub 6}, CF{sub 4}, and C{sub 2}F{sub 6}

    SciTech Connect

    Pitz, Greg A.; Fox, Charles D.; Perram, Glen P.

    2011-09-15

    The cross sections of spin-orbit energy exchange between the cesium 6 {sup 2}P{sub 1/2}{r_reversible}6 {sup 2}P{sub 3/2} states induced by collisions with N{sub 2}, H{sub 2}, HD, D{sub 2}, CH{sub 4}, C{sub 2}H{sub 6}, CF{sub 4}, and C{sub 2}F{sub 6} were obtained for pressures less than 100 Torr at room temperature by means of steady-state laser-induced fluorescence techniques. The spin-orbit energy exchange rate with N{sub 2}, H{sub 2}, HD, D{sub 2}, CH{sub 4}, C{sub 2}H{sub 6}, CF{sub 4}, and C{sub 2}F{sub 6}, have been measured as {sigma}{sub 21}(6 {sup 2}P{sub 3/2}{yields}6 {sup 2}P{sub 1/2})= 16.3, 34.1, 30.0, 22.7, 21.4, 65.6, 64.8, and 137 A{sup 2} and {sigma}{sub 12}(6 {sup 2}P{sub 1/2}{yields}6 {sup 2}P{sub 3/2})= 1.8, 4.4, 4.1, 3.0, 2.9, 13.3, 9.7, and 16.3 A{sup 2}, respectively. Correlations of the spin-orbit transfer probabilities with rotational-energy defect and vibrational-energy defect have been shown.

  4. Energetics and structure of hydroxynicotinic acids. Crystal structures of 2-, 4-, 6-hydroxynicotinic and 5-chloro-6-hydroxynicotinic acids.

    PubMed

    Santos, Rui C; Figueira, Rita M B B M; Piedade, M Fátima M; Diogo, Hermínio P; Minas da Piedade, Manuel E

    2009-10-29

    The relationship between energetics and structure in 2-, 4-, 5-, and 6-hydroxynicotinic and 5-chloro-6-hydroxynicotinic acids (2HNA, 4HNA, 5HNA, 6HNA, and 5Cl6HNA, respectively) was investigated in the solid and gaseous phases by means of a variety of experimental and computational chemistry techniques. The molecular and crystal structures of the 2HNA, 4HNA, 6HNA, and 5Cl6HNA solid forms used in this study were determined by single crystal X-ray diffraction at 293 +/- 2 K. The 2HNA, 4HNA, and 5Cl6HNA samples were monoclinic (space groups: P2(1)/n for 2HNA and P2(1)/c for 4HNA and 5Cl6HNA), and that of 6HNA was found to be triclinic (space group: P1). The 2HNA sample investigated corresponds to a new polymorphic form of this compound. The 2HNA, 4HNA, 6HNA, and 5Cl6HNA molecules crystallize as oxo tautomers exhibiting N-H and Cring=O bonds. This is also supported by the observation of bands typical of N-H and Cring=O stretching frequencies in the corresponding FT-IR spectra. The absence of these bands in the spectrum of 5HNA indicates that a hydroxy tautomer with an unprotonated N heteroatom and a Cring-OH bond is likely to be present in this case. Results of theoretical calculations carried out at the G3MP2 and CBS-QB3 levels of theory suggest that in the ideal gas phase, at 298.15 K, 2HNA favors the oxo form, 4HNA prefers the hydroxy form, and no strong dominance of one of the two tautomers exists in the case of 6HNA and 5Cl6HNA. The standard molar enthalpies of formation of 2HNA, 4HNA, 5HNA, 6HNA, and 5Cl6HNA in the crystalline state, at 298.15 K, Delta(f)H(m)(o)(cr), were determined by micro combustion calorimetry. The corresponding enthalpies of sublimation, Delta(sub)H(m)(o), were also derived from vapor pressure versus temperature measurements by the Knudsen effusion method. The obtained Delta(f)H(m)(o)(cr) and Delta(sub)H(m)(o) values led to the enthalpies of formation of 2HNA, 4HNA, 5HNA, 6HNA, and 5Cl6HNA in the gaseous phase. These were discussed together

  5. Some 1-(diorganooxyphosphonyl)methyl-2,4- and -2,6-dinitro-benzenes

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, John A. (Inventor); Kourtides, Demetrius A. (Inventor)

    1989-01-01

    1-(Diorgano oxyphosphonyl) methyl) 2,4- and 2,6-dinitro- and diamino benzenes are prepared by nitrating an (organophosphonyl)methly benzene to produce the dinitro compounds which are then reduced to the diamino compounds. The organo group (alkyl, haloalkyl, aryl) on the phosphorus may be removed to give the free acids, (HO)2P(double bond O) single bond. The diamino compounds may be polymerized with dianhydrides or diacyl halides to produce fire and flame resistant polymers which are useful in the manufacture of aircraft structures.

  6. The 1-((diorganooxyphosphonyl)-methyl)-2,4- and -2,6-diamido benzenes

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, John A. (Inventor); Kourtides, Demetrius A. (Inventor)

    1989-01-01

    1-((Diorgano oxyphosphonyl) methyl)-2,4- and -2,6-dinitro and diamino benzenes are prepared by nitrating an (organophosphonyl) methyl benzene to produce the dinitro compounds which are then reduced to the diamino compounds. The organo grounds (alkyl, haloalkyl, aryl) on the phosphorus may be removed to give the free acids (HO)2P(double bond O)single bond. The diamino compounds may be polymerized with dianhydrides or diacyl halides to produce fire and flame resistant polymers which are useful in the manufacture of aircraft structures.

  7. Distribution and excretion of 2,4,5,2',4',5'-hexabromobiphenyl, the major component of Firemaster BP-6.

    PubMed

    Matthews, H B; Kato, S; Morales, N M; Tuey, D B

    1977-10-01

    The intestinal absorption, distribution, and excretion of the major component of Firemaster BP-6,2,4,5,2',4',5'-hexabromobiphenyl, has been studied in the male rat. This polybrominated biphenyl was readily absorbed from the intestine, initially distributed throughout the body, and eventually stored primarily in the adipose tissue, was not subject to appreciable metabolism, and was excreted almost exclusively in the feces and at a very slow rate. Approximately 90% of an oral dose was absorbed from the intestine, and extrapolation of the rate of excretion to infinity indicates that less than 10% of the total dose would ever be excreted.

  8. Antibacterial Activity of 2-(2′,4′-Dibromophenoxy)-4,6-dibromophenol from Dysidea granulosa

    PubMed Central

    Shridhar, Divya M. P.; Mahajan, Girish B.; Kamat, Vijayendra P.; Naik, Chandrakant G.; Parab, Rajashri R.; Thakur, Nidhi R.; Mishra, Prabhu D.

    2009-01-01

    2-(2′,4′-Dibromophenoxy)-4,6-dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity, especially against methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), vancomycin resistant Enterococci (VRE), vancomycin sensitive Enterococci (VSE) and Bacillus spp. Minimal inhibitory concentration (MIC) was evaluated against 57 clinical and standard strains of Gram positive and Gram negative bacteria. The observed MIC range was 0.117–2.5 μg/mL against all the Gram positive bacteria and 0.5–2 μg/mL against Gram negative bacteria. The in-vitro antibacterial activity observed was better than that of the standard antibiotic linezolid, a marketed anti-MRSA drug. The results establish 2-(2′,4′-dibromophenoxy)-4,6-dibromophenol, as a potential lead molecule for anti-MRSA and anti-VRE drug development. PMID:19841726

  9. Study of the K2Ni(SO4)26H2O-K2Co(SO4)26H2O-H2O diagram and determination of the conditions for growing K2(Ni,Co)(SO4)26H2O mixed crystals

    NASA Astrophysics Data System (ADS)

    Zhokhov, A. A.; Masalov, V. M.; Zverkova, I. I.; Emelchenko, G. A.; Manomenova, V. L.; Rudneva, E. B.; Vasilieva, N. A.; Voloshin, A. E.

    2016-11-01

    The phase diagram of the K2Ni(SO4)2 · 6H2O-K2Co(SO4)2 · 6H2O-H2O ternary system is investigated in the temperature range of 30-70°C, and a relationship between the compositions of the equilibrium phases of the K2Co x Ni(1- x)(SO4)2 · 6H2O (KCNSH) solid solution and the growth solution is established. It is shown how the salt compositions of the liquid and solid phases change during crystal growth upon slow cooling of solution. A dependence of the lattice parameters of the KCNSH solid solution on the concentration of isomorphic components is experimentally found.

  10. Role of UV photolysis in accelerating the biodegradation of 2,4,6-TCP.

    PubMed

    Wang, Wenbing; Kirumba, George; Zhang, Yongming; Wu, Yanqing; Rittmann, Bruce E

    2015-09-18

    2,4,6-TCP, a kind of chlorinated aromatic and aliphatic compound, is difficult to be biodegraded by ordinary microorganisms. UV photolysis and biodegradation of 2,4,6-TCP by Bacillus amyloliquefaciens intimate coupling is a potential means to accelerate its biotransformation. The initial steps of 2,4,6-TCP biodegradation involve mono-oxygenation reactions that have molecular oxygen and an intracellular electron carrier as cosubstrates. It was demonstrated that B. amyloliquefaciens has the 2,4,6-TCP monooxygenase gene tcpA which could encode 2,4,6-TCP monooxygenase (TCP-MO). TCP-MO would catalytically decompose 2,4,6-TCP into 2,6-DCHQ. We employed an internal loop photolytic biofilm reactor for 2,4,6-TCP degradation. Sequentially coupled photolysis and biodegradation experimental results suggested that 2,4,6-TCP removal rate in P + B (TCP(UV) + phenol) protocol was higher by 77 and 103 % when compared to B (TCP + phenol) and B (TCP-only) protocols respectively. The corresponding loss rate coefficient (k) values were 0.069, 0.039, 0.034 mg/L·min(-1) respectively. This is because UV photolysis converted 2,4,6-TCP into its intermediates: 2,4-dichlorophenol (2,4-DCP), 4-monochlorophenol (4-MCP), phenol, 2,6-dichloro-p-hydroquinone (2,6-DCHQ), with all displaying less inhibition to bacterial action. In addition, phenol was the crucial UV-photolysis product from 2,4,6-TCP, its catabolic oxidation generating internal electron carriers that may accelerate the initial steps of 2,4,6-TCP biodegradation. Intimately coupled photolysis and biodegradation experimental results suggested that 2,4,6-TCP removal rate in P&B (TCP + phenol) protocol was higher by 166 and 681 % when compared to P&B (TCP-only) and P + B protocols respectively. The corresponding loss rate coefficient (k) values were 0.539, 0.203, 0.069 mg/L·min(-1) respectively. It provided sufficient evidence to demonstrate that intimately coupled photolysis and biodegradation accelerated 2,4,6-TCP

  11. Synthesis and structure of A4V6[Te2(4+)Te6+]O24 (A = K, Rb)-two new quaternary mixed-valent tellurium oxides.

    PubMed

    Zhu, Tianxiang; Qin, Jingui; Halasyamani, P Shiv

    2011-09-14

    Two new mixed-valent tellurium oxides with vanadium(V), A(4)V(6)[Te(2)(4+)Te(6+)]O(24) (A = K and Rb), have been synthesized by hydrothermal and conventional solid state techniques. Their structures were determined by single-crystal X-ray diffraction analysis. These two iso-structural compounds exhibit layered structural topologies consisting of [V(6)Te(3)O(24)](4-) anionic units. In these anionic structural units, a Te(6+)O(6) octahedron is connected to six VO(4) tetrahedra by corner-sharing to generate a [V(6)TeO(24)] unit, and each of these [V(6)TeO(24)] units are interconnected by sharing two Te(4+)O(3) polyhedra to complete the infinite [V(6)Te(3)O(24)](4-) sheets. Infrared spectroscopy, UV-Visible diffuse reflectance spectroscopy, and thermogravimetric analysis were also performed on these two compounds. Crystal data: K(4)V(6)Te(3)O(24), trigonal, space group R ̅3c (No. 167) with a = b = 9.7075(6) Å, c = 42.701(3) Å, V = 3484.9(4) Å(3), and Z = 6; Rb(4)V(6)Te(3)O(24), trigonal, space group R ̅3c (No. 167) with a = b = 9.8399(9) Å, c = 43.012(4) Å, V = 3606.6(6) Å(3), and Z = 6.

  12. Intrinsically radiopaque polyurethanes with chain extender 4,4'-isopropylidenebis [2-(2,6-diiodophenoxy)ethanol] for biomedical applications.

    PubMed

    Dawlee, S; Jayabalan, M

    2015-05-01

    Radiopaque polyurethanes are used for medical applications as it allows post-operative assessment of the biomaterial devices using X-ray. Inherently, radiopaque polyurethanes based on polytetramethylene glycol (PTMG), polypropylene glycol, 4,4'-methylenebis(phenyl isocyanate), and a new iodinated chain extender 4,4'-isopropylidenebis[2-(2,6-diiodophenoxy)ethanol] with flexible spacers were synthesized and characterized. The iodinated polyurethanes were clear, optically transparent, and had high molecular weights. The polyurethanes also possessed excellent radiopacity and high thermal stability. The biocompatibility of the most promising iodinated polyurethane was evaluated both in vitro (cytotoxicity evaluation by direct contact and MTT assay, using L929 mouse fibroblast cells) and in vivo (toxicology studies in rabbits and subcutaneous implantation in rats). The material was nontoxic and well tolerated by the animals. Thus, these radiopaque and transparent polyurethanes are expected to have potential for various biomedical applications.

  13. A temperature-induced order-disorder phase transition in a 4-substituted 4,2':6',4''-terpyridine.

    PubMed

    Granifo, Juan; Westermeyer, Marleen; Riquelme, Maricel; Gaviño, Rubén; Suárez, Sebastián; Halac, Emilia B; Baggio, Ricardo

    2015-12-01

    Crystals of 4'-(isoquinolin-4-yl)-4,2':6',4''-terpyridine (iqtp), C24H16N4, grown from an ethanol solution, undergo a reversible first-order single-crystal to single-crystal phase transition at Tc in the range 273-275 K, from a disordered higher-temperature phase [form (I)] in the space group P21/c, with one single molecule in the asymmetric unit, to an ordered lower-temperature one [form (II)] in the space group P21/n, with two independent molecules in the asymmetric unit. There is a group-subgroup relationship linking (I)-(II), due to cell doubling and the disappearance of a number of symmetry operations. In addition to X-ray diffraction, the transition has been monitored by Raman spectroscopy and differential scanning calorimetry, the latter disclosing an enthalpy change of 0.72 (6) kJ mol(-1). Variations of the unit-cell parameters with temperature between 170 and 293 K are presented. The evolution of diffraction spots in the vicinity of the transition temperature shows the coexistence of both phases, confirming the first-order character of the transition. Structural details of both phases are analyzed and intermolecular interactions compared in order to investigate the mechanism of the phase transition. A three-dimensional Hirshfeld surface analysis was performed to corroborate the significant changes in the intermolecular features.

  14. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  15. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  16. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  17. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  18. 40 CFR 721.5260 - 1,3,6-Naphthalenetrisulfonic acid, 7-[[2-[(aminocarbonyl)amino]- 4-[[4-[[2-[2-(ethenylsulfonyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...,3,6-Naphthalenetrisulfonic acid, 7- - 4- ethyl]amino]- 6-fluoro-1,3,5-triazin-2-yl]amino]phenyl]azo... substance identified as 1,3,6-Naphthalenetrisulfonic acid, 7- -4- ethyl]amino]-6-fluoro-1,3,5-triazin-2-yl... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 1,3,6-Naphthalenetrisulfonic acid,...

  19. 40 CFR 721.5260 - 1,3,6-Naphthalenetrisulfonic acid, 7-[[2-[(aminocarbonyl)amino]- 4-[[4-[[2-[2-(ethenylsulfonyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...,3,6-Naphthalenetrisulfonic acid, 7- - 4- ethyl]amino]- 6-fluoro-1,3,5-triazin-2-yl]amino]phenyl]azo... substance identified as 1,3,6-Naphthalenetrisulfonic acid, 7- -4- ethyl]amino]-6-fluoro-1,3,5-triazin-2-yl... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,3,6-Naphthalenetrisulfonic acid,...

  20. 40 CFR 721.5260 - 1,3,6-Naphthalenetrisulfonic acid, 7-[[2-[(aminocarbonyl)amino]- 4-[[4-[[2-[2-(ethenylsulfonyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...,3,6-Naphthalenetrisulfonic acid, 7- - 4- ethyl]amino]- 6-fluoro-1,3,5-triazin-2-yl]amino]phenyl]azo... substance identified as 1,3,6-Naphthalenetrisulfonic acid, 7- -4- ethyl]amino]-6-fluoro-1,3,5-triazin-2-yl... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,3,6-Naphthalenetrisulfonic acid,...

  1. 40 CFR 721.5260 - 1,3,6-Naphthalenetrisulfonic acid, 7-[[2-[(aminocarbonyl)amino]- 4-[[4-[[2-[2-(ethenylsulfonyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...,3,6-Naphthalenetrisulfonic acid, 7- - 4- ethyl]amino]- 6-fluoro-1,3,5-triazin-2-yl]amino]phenyl]azo... substance identified as 1,3,6-Naphthalenetrisulfonic acid, 7- -4- ethyl]amino]-6-fluoro-1,3,5-triazin-2-yl... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1,3,6-Naphthalenetrisulfonic acid,...

  2. 40 CFR 721.5260 - 1,3,6-Naphthalenetrisulfonic acid, 7-[[2-[(aminocarbonyl)amino]- 4-[[4-[[2-[2-(ethenylsulfonyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...,3,6-Naphthalenetrisulfonic acid, 7- - 4- ethyl]amino]- 6-fluoro-1,3,5-triazin-2-yl]amino]phenyl]azo... substance identified as 1,3,6-Naphthalenetrisulfonic acid, 7- -4- ethyl]amino]-6-fluoro-1,3,5-triazin-2-yl... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 1,3,6-Naphthalenetrisulfonic acid,...

  3. Synthesis of Heteroaryl Sulfonamides from Organozinc Reagents and 2,4,6-Trichlorophenyl Chlorosulfate.

    PubMed

    Colombe, James R; DeBergh, J Robb; Buchwald, Stephen L

    2015-06-19

    A method for the preparation of aryl and heteroaryl sulfonamides using 2,4,6-trichlorophenyl chlorosulfate (TCPC) is described. The reaction of 2-pyridylzinc reagents with TCPC resulted in 2,4,6-trichlorophenyl (TCP) pyridine-2-sulfonates, and the parent pyridine-2-sulfonate was shown to react with amines. Less electron-rich aryl- and heteroarylzinc reagents reacted with TCPC to afford sulfonyl chlorides that were converted in situ to sulfonamides.

  4. Superconductivity in new iron pnictide oxide Fe2As2Sr4(Mg,Ti)2O6

    NASA Astrophysics Data System (ADS)

    Sato, Shinya; Ogino, Hiraku; Kishio, Kohji; Shimoyama, Jun-Ichi

    2010-03-01

    A new iron arsenide oxide Fe2As2Sr4MgTiO6, which is isostructural with the iron-based superconductor Fe2Pn2Sr4M2O6^[1,2], has been successfully synthesized by the solid-state reaction in quartz ampoules. Fe2As2Sr4MgTiO6 has antifluorite-type iron arsenide layer and K2NiF4-type oxide layer, while the M-site is composed of a combination of divalent (Mg^2+) and tetravalent (Ti^4+) cations as in the case of a double perovskite La(Mg,Ti)O3. This fact indicates chemical flexibility of the perovskite-related layer in this system. This compound showed bulk superconductivity with Tc of ˜20 K by partial substitution of Co for Fe. Moreover, high Tc above 35 K was recorded by samples starting from Co-free and Ti-rich compositions, Fe2As2Sr4(Mg1-xTix)2O6 (x =0.7˜0.8). [1] H. Ogino et al., Supercond. Sci. Technol. 22 (2009) 075008. [2] X. Zhu et al., Phys. Rev. B 79 (2009) 220512(R).

  5. Monoclinic structure of hydroxylpyromorphite Pb10(PO4)6(OH)2 - hydroxylmimetite Pb10(AsO4)6(OH)2 solid solution series

    NASA Astrophysics Data System (ADS)

    Giera, Alicja; Manecki, Maciej; Borkiewicz, Olaf; Zelek, Sylwia; Rakovan, John; Bajda, Tomasz; Marchlewski, Tomasz

    2016-04-01

    Seven samples of hydroxyl analogues of pyromorphite-mimetite solid solutions series were synthesized from aqueous solutions at 80° C in a computer-controlled chemistate: 200 mL aqueous solutions of 0.05M Pb(NO3)2 and 0.03M KH2AsO4 and/or KH2PO4 were dosed with a 0.25 mL/min rate to a glass beaker, which initially contained 100 mL of distilled water. Constant pH of 8 was maintained using 2M KOH. The syntheses yielded homogeneous fine-grained white precipitates composition of which was close to theoretical Pb10[(PO4)6-x(AsO4)x](OH)2, where x = 0, 1, 2, 3, 4, 5, 6. High-resolution powder X-ray diffraction data were obtained in transmission geometry at the beamline 11-BM at the Advanced Photon Source (Argonne National Laboratory in Illinois, USA). The structure Rietveld refinements based on starting parameters of either hexagonal hydroxylpyromorphite or monoclinic mimetite-M were performed using GSAS+EXPGUI software. Apatite usually crystallizes in the hexagonal crystal system with the space group P63/m. For the first time, however, the lowering of the hexagonal to monoclinic crystal symmetry was observed in the hydroxyl variety of pyromorphite-mimetite solid solution series. This is indicated by better fitting of the modeled monoclinic structure to the experimental data. The same is not the case for analogous calcium hydroxylapatite series Ca5(PO4)3OH - Ca5(AsO4)3OH (Lee et al. 2009). Systematical linear increase of unit cell parameters is observed with As substitution from a=9.88, b=19.75, and c=7.43 for Pb10(PO4)6(OH)2 to a=10.23, b=20.32, and c=7.51 for Pb10(AsO4)6(OH)2. A strong pseudohexagonal character (γ ≈ 120° and b ≈ 2a) of the analyzed monoclinic phases was established. This work is partially funded by AGH research grant no 11.11.140.319 and partially by Polish NCN grant No 2011/01/M/ST10/06999. Lee Y.J., Stephens P.W., Tang Y., Li W., Philips B.L., Parise J.B., Reeder R.J., 2009. Arsenate substitution in hydroxylapatite: Structural characterization

  6. Glycosylation, sugar hydrazones, and antimicrobial evaluation of some 6-substituted-1,2,4-triazines.

    PubMed

    El-Barbary, A A; Hafiz, Y A; Abdel-Wahed, M S

    2010-01-01

    Hydrazinolysis of 4-amino-6-[2-(4-methoxyphenyl)vinyl]-3-thioxo-3,4-dihydro-2H-[1,2,4] triazin-5-one (1) gave the corresponding hydrazino derivatives (2) Cyclocondensation of (2) with carbon disulfide furnished 8-amino-6-[2-(4-methoxyphenyl)vinyl]-3-thioxo-2,8-dihydro-3H-[1,2,4]triazolo[4,3-b][1,2,4]triazin-7-one (3) which was treated with 2,3,4,6- tetra-O-acetyl-alpha-D-glucopyranosyl bromide (4) in pyridine to give the corresponding N-glucosyl derivative 5, which deblocked to give 8. Compound 2 was reacted with isatin 9 and/or isatoic anhydride 10 to afford 11 and 12. Treatment of 11 and 12 with (4) in pyridine gave the corresponding mono glucosyl derivatives 13 and 14, which were deblocked by ammonia and afforded 15 and 16. Condensation of 2 with aldoses afforded the corresponding cyclic products 17a-f and with D-fructose furnished 18. Acetylation of 17b, d afforded the corresponding polyacetyl derivatives 19b,d. Compound 2 condensed with some aromatic aldehydes in boiling methanol and gave 20a-f. The newly synthesized compounds were tested as antimicrobial agents.

  7. n-Propyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyran-oside.

    PubMed

    Mönch, Bettina; Emmerling, Franziska; Kraus, Werner; Becker, Roland; Nehls, Irene

    2013-02-01

    THE TITLE COMPOUND [SYSTEMATIC NAME: (2R,3R,4S,5R,6R)-2-(acet-oxy-meth-yl)-6-propoxytetra-hydro-2H-pyran-3,4,5-triyl triacetate], C(17)H(26)O(10), was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide and n-propanol. The central ring adopts a chair conformation. The crystal does not contain any significant inter-actions such as hydrogen bonds.

  8. Phase transition and glass transition concerning configurational order/disorder of ions in crystalline (TMA) 2[Sr{Ni(pro) 2} 6](ClO 4) 4 and (TMA)[Sm{Ni(pro) 2} 6](ClO 4) 4

    NASA Astrophysics Data System (ADS)

    Yukawa, Y.; Igarashi, S.; Masuda, Y.; Oguni, M.

    2002-03-01

    Crystalline (TMA) 2[Sr{Ni(pro) 2} 6](ClO 4) 4 was synthesized newly and its structure was determined, where TMA and pro denote tetramethylammonium and L-prolinato, respectively. Heat capacities of crystalline (TMA) 2[Sr{Ni(pro) 2} 6](ClO 4) 4 and (TMA)[Sm{Ni(pro) 2} 6](ClO 4) 4 were measured at low temperatures by using an adiabatic calorimeter. In the former compound, a phase transition of the first order was found to occur at (160±1) K with a sharp heat-capacity peak. The enthalpy and entropy of the transition were estimated to be (11.0±0.2) and (69.4±1.5) JK -1 mol -1, respectively. In the latter compound, a phase transition of the first order and a glass transition were found at (190±1) and (162±2) K, respectively. The entropy of the phase transition was estimated to be in the range 20-45 JK -1 mol -1. The phase transitions were attributed to the orientational order/disorder process of perchlorate ions ClO 4-, and it was suggested that each ClO 4- ion has six and three distinguishable, reasonably stable orientations in the high-temperature disordered phase for the Sr II and Sm III complex compounds, respectively. The glass transition was interpreted as a freezing-in phenomenon of the reorientational motion of ClO 4- ions, and the activation energy for the motion was estimated to be (53±1) kJ mol -1 and less than 39 kJ mol -1 for the Sm III and Sr II complex compounds, respectively; the removal of one of the two TMA ions neighboring to the ClO 4- ion leads to an increase in the activation energy. It is discussed that the cooperative interaction between the orientations of the ClO 4- ions operates through the orientational and positional shifts of TMA ions, and thus the lattice deformation in the relevant region, associated with the orientational change of the ClO 4- ions. Then it is noted that the position of the ClO 4- ion itself would shift to form preferable ionic interaction, for example through a kind of hydrogen bond of C-H δ+ ⋯ δ- O-Cl, for

  9. Crystal structure of 4,4',4''-(1,3,5-triazine-2,4,6-tri-yl)tripyridinium trichloride 2.5-hydrate.

    PubMed

    Ling, Bo-Kai; Feng, Xiao-Long; Li, Yang; Luan, Tian-Gang

    2015-11-01

    The asymmetric unit of the title compound, C18H15N6 (3+)·3Cl(-)·2.5H2O, contains two independent (1,3,5-triazine-2,4,6-tri-yl)tripyridinium cations. Both cations are approximately planar, the r.m.s. deviations of fitted non-H atoms being 0.045 and 0.051 Å. In the crystal, extensive O-H⋯Cl, O-H⋯O, N-H⋯Cl and N-H⋯O hydrogen bonds and weak C-H⋯Cl and C-H⋯O inter-actions link the organic cations, Cl(-) anions and water mol-ecules into a three-dimensional supra-molecular architecture. π-π stacking between the pyridine rings of adjacent cations is also observed, the centroid-to-centroid distance being 3.7578 (8) Å.

  10. Bioconversion of 2,4-diamino-6-nitrotoluene to a novel metabolite under anoxic and aerobic conditions.

    PubMed Central

    Gilcrease, P C; Murphy, V G

    1995-01-01

    Under nitrate-reducing, nongrowth conditions, a Pseudomonas fluorescens species reduced 2,4,6-trinitrotoluene to aminodinitrotoluenes, which were then further reduced to diaminonitrotoluenes. 2,4-Diamino-6-nitrotoluene (2,4-DANT) was further transformed to a novel metabolite, 4-N-acetylamino-2-amino-6-nitrotoluene (4-N-AcANT), while 2,6-diamino-4-nitrotoluene (2,6-DANT) was persistent. Efforts to further degrade 2,4-DANT and 2,6-DANT under aerobic, nitrogen-limited conditions were unsuccessful; 2,6-DANT remained persistent, and 2,4-DANT was again transformed to the 4-N-AcANT compound. PMID:8534088

  11. Vibrational and elastic properties of As4O6 and As4O6.2He at high pressures: Study of dynamical and mechanical stability

    NASA Astrophysics Data System (ADS)

    Cuenca-Gotor, V. P.; Gomis, O.; Sans, J. A.; Manjón, F. J.; Rodríguez-Hernández, P.; Muñoz, A.

    2016-10-01

    The formation of a new compound with stoichiometry As4O6.2He at relatively low pressure (3 GPa) has been recently reported when arsenolite (As4O6) powder is compressed with helium as a pressure-transmitting medium. In this work, we study the lattice dynamics of As4O6 and As4O6.2He at high pressures from an experimental and theoretical perspective by means of Raman scattering measurements and ab initio calculations and report the theoretical elastic properties of both compounds at high pressure. Raman scattering measurements show a completely different behaviour of As4O6 and As4O6.2He at high pressures. Furthermore, the theoretical calculation of phonon dispersion curves and elastic stiffness coefficients at high pressure in both compounds allow us to discuss their dynamical and mechanical stability under hydrostatic compression. Both compounds are dynamically stable even above 35 GPa, but As4O6 becomes mechanically unstable at pressures beyond 19.7 GPa. These results allow explaining the pressure-induced amorphization of As4O6 found experimentally above 15-20 GPa and the lack of observation of any instability in As4O6.2He up to the highest studied pressure (30 GPa).

  12. Exposure to 2,4- and 2,6-toluene diisocyanate (TDI) during production of flexible foam: determination of airborne TDI and urinary 2,4- and 2,6-toluenediamine (TDA).

    PubMed

    Kääriä, K; Hirvonen, A; Norppa, H; Piirilä, P; Vainio, H; Rosenberg, C

    2001-07-01

    Occupational exposure to 2,4- and 2,6-toluene diisocyanate (2,4- and 2,6-TDI) was measured during the production of flexible foam. The usefulness of urinalysis of the TDI-derived amines, 2,4- and 2,6-toluenediamine (2,4- and 2,6-TDA), for exposure assessment was compared with air monitoring. Urine samples were collected from 17 employees at two plants. The workers' personal exposure was measured using 1-(2-methoxyphenyl)-piperazine (2MP)-impregnated glass fibre filters for sampling and high-performance liquid chromatography (HPLC) with ultraviolet (UV) and electrochemical (EC) detection for quantification. The limit of detection (LOD) of 2,4- and 2,6-TDI was 0.01 microtg ml(-1) for a 20 microl injection. The precision of sample preparation, expressed as the relative standard deviation (RSD), was 0.6% with UV detection and 0.8% with EC detection at a 2,4-TDI concentration of 0.2 microg ml(-1) (n = 6). For 2,6-TDI, the corresponding RSDs were 0.5% and 0.8%. The urinary 2,4- and 2,6-TDA metabolites were determined after acid hydrolysis as heptafluorobutyric anhydride derivatives by gas chromatography-mass spectrometry. The LOD in urine was 0.35 nmol l(-1) for 2,4-TDA and 0.04 nmol l(-1) for 2,6-TDA. The precision (RSD) of six analyses of human urine spiked to a concentration of 100 nmol l(-1) was 3.7% for 2,4-TDA and 3.6% for 2,6-TDA. There was a trend for linear correlation between urinary TDA concentration and the product of airborne TDI concentration and sampling time. Urinalysis of TDA is proposed as a practical method for assessing personal exposures in workers exposed intermittently to TDI.

  13. Oxidative degradation of 2,4-xylidine by photosensitization with 2,4,6-triphenylpyrylium: homogeneous and heterogeneous catalysis.

    PubMed

    Amat, Ana M; Arques, Antonio; Bossmann, Stefan H; Braun, André M; Göb, Sabine; Miranda, Miguel A; Oliveros, Esther

    2004-12-01

    The possibility of using zeolites containing the 2,4,6-triphenylpyrylium cation as photocatalysts for the degradation of pollutants has been tested on aqueous xylidine (2,4-dimethylaniline) solutions as models for contaminated wastewaters. The influence of the photocatalyst and substrate concentrations on xylidine oxidation has been investigated in homogeneous solution, by performing a series of experiments chosen according to the experimental design methodology (Doehlert uniform array). The empirical models and the corresponding response surfaces obtained from data analysis have been used for simulating and predicting degradation efficiency. The results have shown that conversion increases with increasing amounts of photocatalyst and decreasing concentration of the model pollutant. The fluorescence of 2,4,6-triphenylpyrylium was quenched by xylidine with a rate constant k(q) of 3.1x10(9)M(-1)s(-1). This result suggests a direct electron transfer between the excited pyrylium salt and xylidine. Because of the limited stability of the photocatalyst in homogeneous media, a pyrylium containing Y-zeolite has been tested for the photocatalytic oxidation of xylidine under heterogeneous conditions. The results suggest that the supported catalyst has a much improved stability and that xylidine oxidation rates remain nearly constant during the whole reaction time. An additional advantage of the pyrylium containing zeolite photocatalyst is that it can be recycled and used for further experiments.

  14. 3-Amino-2-carbamoyl-4,6-diphenyl-4,5- and -4,7-dihydrothieno-(2,3-b)pyridines

    SciTech Connect

    Krauze, A.A.; Liepin'sh, E.E.; Dubur, G.Ya.

    1987-10-01

    The treatment of piperidinium salts of 3-cyano-1,4-dihydropyridine-2-thiols with alkyl halides leads to 2-alkylthio-3-cyano-1,4-dihydropyridines. The authors have shown that alkylation of the piperidinium salt of 4,6-diphenyl-3-cyano-1,4-dihydropyridine-2-thiol with iodoacetamide gives carbamoylmethylthio derivative II, which, by the action of an equimolar amount of a base with heating to 50-60/sup 0/C, gives a mixture of 3-amino-2-carbamoyl-4,6-diphenyl-4,7-dihydrothieno(2,3-b)pyridine and 3-amino-2-carbamoyl-4,6-diphenyl-4,5-dihydrothieno(2,3-b)-pyridine in a ratio of 1:1. In the presence of excess base the principal product is IV. It was established by PMR spectroscopy that dihydropyridine II initially undergoes cyclization to 4,7-dihydrothienopyridine III, which then undergoes isomerization to 4,5-dihydrothienopyridine IV. Acidification of a solution of IV in d/sub 6/-DMSO gives rise to reverse isomerization.

  15. 1,2,3,3′,4′,6′-Hexaacetyl-4,6-O-benzyl­idenesucrose

    PubMed Central

    Brito-Arias, Marco A.; Soto-Ortega, Miguel; García-Báez, Efrén V.

    2011-01-01

    In the title compound, C31H38O17, the 1,3-dioxane and pyran­oside rings both show 4 C 1 chair conformations while for the d-fructofuran­oside moiety an envelop 3E conformation is observed. The phenyl ring is oriented almost perpendicular to the 1,3-dioxane ring [dihedral angle = 79.3 (2)°], and the acetate groups are equatorial for the pyran­oside ring and axial for the furan­oside ring. The analysis of potential hydrogen bonds shows both intra- and inter­molecular C—H⋯O contacts to be present. PMID:21523142

  16. Synthesis and antifungal activity of natural product-based 6-alkyl-2 3 4 5-tetrahydropyridines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven 6-alkyl-2,3,4,5-tetrahydropyridines (5a–5g) that mimic the natural products piperideines that were recently identified in the fire ant venom have been synthesized. Compounds 5c–5g with the C-6 alkyl chain lengths from C14 to C18 showed varying degrees of antifungal activities, with 5e (6-hexa...

  17. Synthesis and anticonvulsant activity of 6-alkoxy-[1,2,4]triazolo[3,4-a]phthalazines.

    PubMed

    Zhang, Lei; Guan, Li-Ping; Sun, Xian-Yu; Wei, Cheng-Xi; Chai, Kyu-Yun; Quan, Zhe-Shan

    2009-03-01

    A new series of 6-alkoxy-[1,2,4]triazolo[3,4-a]phthalazines (3a-3v) were synthesized and their anticonvulsant activity and neurotoxicity were evaluated by the maximal electroshock test and the rotarod test respectively. Significant anticonvulsant activity was displayed by a number of compounds. The most promising compounds 6-(4-chlorobenzyloxy)-[1,2,4]triazolo[3,4-a]phthalazine (3f) and 6-heptyloxy-[1,2,4]triazolo[3,4-a]phthalazine (3s) showed a median effective dose of 7.1 and 11.0 mg/kg, and had protective index value of 5.2 and 8.0 respectively. The two compounds were further found to have potent activity against seizures induced by pentylenetetrazole, isoniazid, thiosemicarbazide, 3-mercaptopropionic acid but not seizures induced by strychnine, indicating that the two compounds might function by enhancing gamma-aminobutyric acid neurotransmission.

  18. Synthesis, structure and properties of tetrachlorido[N2,N2,N4,N4,N6,N6-hexakis((pyridin-2-yl)methyl)-1,3,5-triazine-2,4,6-triamine]dicopper(II) bis(acetonitrile), [Cu2Cl4(L)]·2CH3CN

    NASA Astrophysics Data System (ADS)

    Uma Maheswari, Palanisamy; van Albada, Gerard A.; Modec, Barbara; Kozlevčar, Bojan; Reedijk, Jan

    2012-04-01

    The bisadduct of Cu(II) chloride with the potential nonadentate ligand N2,N2,N4,N4,N6,N6-hexakis((pyridin-2-yl)methyl)-1,3,5-triazine-2,4,6-triamine, [Cu2Cl4(L)]·2CH3CN, is described. Each of the 2 Cu(II) ions is in a 5-coordinate geometry, intermediate between square pyramidal and tetragonal pyramidal, comprising a CuN3Cl2 chromophore. The intramolecular Cu-Cu distance of 7.511(2) Å is too large for a significant magnetic interaction, as confirmed by EPR spectroscopy. All Cu-N and Cu-Cl distances are as commonly found. An acetonitrile solvent molecule is filling a lattice cavity. Packing interactions also appear as normal and intermolecular Cu-Cu contacts are 8.773(2) and 9.991(2) Å.

  19. Purification and properties of 2-hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid hydrolase involved in microbial degradation of carbazole.

    PubMed

    Riddle, Robert R; Gibbs, Phillip R; Willson, Richard C; Benedik, Michael J

    2003-03-01

    Hydrolysis following meta-ring cleavage by a dioxygenase is a well-known step in aromatic compound metabolism. The 2-hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid hydrolase from Pseudomonas LD2 is a new member of the small group of characterized aromatic hydrolases that catalyze the cleavage of C-C bonds. In this study, the His(6)-tagged 2-hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid (HOPDA) hydrolase was purified from a recombinant Escherichia coli strain utilizing immobilized metal affinity chromatography. 2-Hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid hydrolase is a colorless homodimer with no cofactor requirement. The enzyme actively converted HOPDA into benzoic acid and 2-hydroxypenta-2,4-dienoic acid. The enzyme exhibited activity between pH 6.5 and 10.5 with a maximum activity at pH 7.0. The optimum temperature at pH 7.0 was 60 degrees C. The calculated K'(m) for HOPDA was 4.6 microM, the V(max) was 3.3 micromol min(-1), and the K(s) was 70.0 microM. This corresponds to a maximum specific turnover rate of 1300 HOPDAs(-1)dimer(-1). The deduced amino acid sequence of CarC showed 30.3, 31.3, and 31.8% identity with TodF (P. putida F1), XylF (P. putida), and DmpD (Pseudomonas sp. CF600), respectively, which are meta-cleavage compound hydrolases from other Pseudomonads. The amino acid sequence Gly-X-Ser-X-Gly, which is highly conserved in these hydrolases, is also found in CarC. Lysates from a strain expressing enzyme in which the putative active site serine is mutated to alanine showed a significant reduction in activity.

  20. Interplay of magnetic sublattices in langite Cu4(OH)6SO4 · 2H2O

    NASA Astrophysics Data System (ADS)

    Lebernegg, S.; Tsirlin, A. A.; Janson, O.; Redhammer, G. J.; Rosner, H.

    2016-03-01

    Magnetic and crystallographic properties of the mineral langite Cu4(OH)6SO{}4\\cdot 2H2O are reported. Thermodynamic measurements combined with a microscopic analysis, based on density-functional bandstructure calculations, identify a quasi-two-dimensional (2D), partially frustrated spin-1/2 lattice resulting in the low Néel temperature of {T}{{N}}≃ 5.7 K. This spin lattice splits into two parts with predominant ferro- and antiferromagnetic (AFM) exchange couplings, respectively. The former, ferromagnetic (FM) part is prone to the long-range magnetic order and saturates around 12 T, where the magnetization reaches 0.5 {μ }{{B}}/Cu. The latter, AFM part features a spin-ladder geometry and should evade long-range magnetic order. This representation is corroborated by the peculiar temperature dependence of the specific heat in the magnetically ordered state. We argue that this separation into ferro- and antiferromagnetic sublattices is generic for quantum magnets in Cu2+ oxides that combine different flavors of structural chains built of CuO4 units. To start from reliable structural data, the crystal structure of langite in the 100-280 K temperature range has been determined by single-crystal x-ray diffraction, and the hydrogen positions were refined computationally.

  1. Mammalian toxicology and human exposures to the flame retardant 2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol (TBBPA): implications for risk assessment.

    PubMed

    Colnot, Thomas; Kacew, Sam; Dekant, Wolfgang

    2014-03-01

    The compound 2,2',6,6'-Tetrabromo-4,4'-isopropylidenediphenol (tetrabromobisphenol A, TBBPA) is used as a reactive and additive flame retardant. This review evaluates the mammalian toxicology of TBBPA and summarizes recent human exposure and risk assessments. TBBPA has a low potential for systemic or reproductive toxicity, and no-observed-adverse-effect-levels were greater than 1,000 mg/kg body weight (bw)/day in a 90-day oral toxicity study, a developmental toxicity study and a two-generation reproductive and developmental toxicity study. Some interactions of TBBPA with hormone-mediated pathways were noted in vitro; however, when studied in vivo, TBBPA did not produce adverse effects that might be considered to be related to disturbances in the endocrine system. Therefore, in accordance with internationally accepted definitions, TBBPA should not be considered an "endocrine disruptor." Furthermore, TBBPA is rapidly excreted in mammals and therefore does not have a potential for bioaccumulation. Measured concentrations of TBBPA in house dust, human diet and human serum samples are very low. Daily intakes of TBBPA in humans were estimated to not exceed a few ng/kg bw/day. Due to the low exposures and the low potential for toxicity, margins of exposures for TBBPA in the human population were between 6 × 10(4) (infants) to 6 × 10(7) (adults). Exposures of the general population are also well below the derived-no-effect-levels derived for endpoints of potential concern in REACH.

  2. Phosphatidylinositol 4,5-bisphosphate (PIP(2)) controls magnesium gatekeeper TRPM6 activity.

    PubMed

    Xie, Jia; Sun, Baonan; Du, Jianyang; Yang, Wenzhong; Chen, Hsiang-Chin; Overton, Jeffrey D; Runnels, Loren W; Yue, Lixia

    2011-01-01

    TRPM6 is crucial for human Mg2+ homeostasis as patients carrying TRPM6 mutations develop hypomagnesemia and secondary hypocalcemia (HSH). However, the activation mechanism of TRPM6 has remained unknown. Here we demonstrate that phosphatidylinositol-4,5-bisphophate (PIP2) controls TRPM6 activation and Mg2+ influx. Stimulation of PLC-coupled M1-receptors to deplete PIP2 potently inactivates TRPM6. Translocation of over-expressed 5-phosphatase to cell membrane to specifically hydrolyze PIP2 also completely inhibits TRPM6. Moreover, depolarization-induced-activation of the voltage-sensitive-phosphatase (Ci-VSP) simultaneously depletes PIP2 and inhibits TRPM6. PLC-activation induced PIP2-depletion not only inhibits TRPM6, but also abolishes TRPM6-mediated Mg2+ influx.Furthermore, neutralization of basic residues in the TRP domain leads to nonfunctional or dysfunctional mutants with reduced activity by PIP2, suggesting that they are likely to participate in interactions with PIP2.Our data indicate that PIP2 is required for TRPM6 channel function; hydrolysis of PIP2 by PLC-coupled hormones/agonists may constitute an important pathway for TRPM6 gating, and perhaps Mg2+ homeostasis.

  3. 2,4,6-Trinitrotoluene reduction by carbon monoxide dehydrogenase from Clostridium thermoaceticum

    SciTech Connect

    Huang, S.; Lindahl, P.A.; Wang, C.; Bennett, G.N.; Rudolph, F.B.; Hughes, J.B.

    2000-03-01

    Purified CO dehydrogenase (CODH) from Clostridium thermoaceticum catalyzed the transformation of 2,4,6-trinitrotoluene (TNT). The intermediates and reduced products of TNT transformation were separated and appear to be identical to the compounds formed by C. acetobutylicum, namely, 2-hydroxylamino-4,6-dinitrotoluene (2 HA46DNT), 4-hydroxylamino-2,6-dinitrotoluene (4HA26DNT), 2,4-dihydroxylamino-6-nitrotoluene (24DHANT), and the Bamberger rearrangement product of 2,4-dihydroxylamino-6-nitrotoluene. In the presence of saturating CO, CODH catalyzed the conversion of TNT to two monohydroxylamino derivatives (2HA46DNT and 4HA26DNT), with 4HA26DNT as the dominant isomer. These derivatives were then converted to 24DHANT, which slowly converted to the Bamberger rearrangement product. Apparent K{sub m} and k{sub cat} values of TNT reduction were 165 {+-} 43 {micro}M for TNT and 400 {+-} 94 s{sup {minus}1}, respectively. Cyanide, an inhibitor for the CO/CO{sub 2} oxidation/reduction activity of CODH, inhibited the TNT degradation activity of CODH.

  4. 2,4,6-trinitrotoluene reduction by carbon monoxide dehydrogenase from Clostridium thermoaceticum.

    PubMed

    Huang, S; Lindahl, P A; Wang, C; Bennett, G N; Rudolph, F B; Hughes, J B

    2000-04-01

    Purified CO dehydrogenase (CODH) from Clostridium thermoaceticum catalyzed the transformation of 2,4,6-trinitrotoluene (TNT). The intermediates and reduced products of TNT transformation were separated and appear to be identical to the compounds formed by C. acetobutylicum, namely, 2-hydroxylamino-4,6-dinitrotoluene (2HA46DNT), 4-hydroxylamino-2,6-dinitrotoluene (4HA26DNT), 2, 4-dihydroxylamino-6-nitrotoluene (24DHANT), and the Bamberger rearrangement product of 2,4-dihydroxylamino-6-nitrotoluene. In the presence of saturating CO, CODH catalyzed the conversion of TNT to two monohydroxylamino derivatives (2HA46DNT and 4HA26DNT), with 4HA26DNT as the dominant isomer. These derivatives were then converted to 24DHANT, which slowly converted to the Bamberger rearrangement product. Apparent K(m) and k(cat) values of TNT reduction were 165 +/- 43 microM for TNT and 400 +/- 94 s(-1), respectively. Cyanide, an inhibitor for the CO/CO(2) oxidation/reduction activity of CODH, inhibited the TNT degradation activity of CODH.

  5. Development of 6H-Chromeno[3,4-c]pyrido[3',2':4,5]thieno[2,3-e]pyridazin-6-ones as Par-4 Secretagogues

    PubMed Central

    Frasinyuk, Mykhaylo S.; Bondarenko, Svitlana P.; Sviripa, Vitaliy M.; Burikhanov, Ravshan; Rangnekar, Vivek M.; Liu, Chunming; Watt, David S.

    2015-01-01

    Nitrosation and cyclization of 4-(3-aminothieno[2,3-b]pyridine-2-yl)-2H-chromen-2-ones 1 afforded substituted 6H-chromeno[3,4-c]pyrido[3',2':4,5]thieno[2,3-e]pyridazin-6-ones 2 that inhibited the intermediary filament protein, vimentin, at low micromolar concentrations. This inhibition promoted the secretion of Prostate Apoptosis Response-4 protein (Par-4), which selectively triggered apoptosis in prostate cancer cells such as CWR22Rv1, LNCaP-derivative C4-2B, PC-3 and its aggressive analog, PC-3 MM2. PMID:26236052

  6. Site occupation and photoluminescence properties of Ce3+ in Sr4Ca4La2 (PO4)6O2: Experiments and ab initio calculations

    NASA Astrophysics Data System (ADS)

    Zhou, Rongfu; Ning, Lixin; Zhou, Weijie; Lin, Litian; Shi, Rui; Liang, Hongbin

    2017-04-01

    Cerium-doped oxyapatite phosphors, Sr4Ca4La2(PO4)6O2: Ce3+, are prepared by a traditional solid-state reaction method. X-ray diffraction (XRD) refinement reveals that the hexagonal Sr4Ca4La2(PO4)6O2 structure is characterized by a random distribution of Sr and Ca atoms on the nine-coordinated cationic 4f sites and of Sr, Ca, and La atoms on the seven-coordinated cationic 6 h sites. Photoluminescence properties of Ce-doped samples are then studied with excitation energies in the vacuum-ultraviolet (VUV) to ultraviolet (UV) range at low temperature. Three main types of occupation sites for Ce3+ are identified based on analysis of emission and excitation spectra and of luminescence decay behaviors. The Ce3+ occupation on the seven-coordinated La (6 h) site is found to be dominant, which is supported by wave function-based CASSCF/CASPT2 embedded cluster calculations on Ce3+ 4f → 5d transition energies at the spin-orbit level. The role of the coordinated oxygen ion that is not bonded with P5+ in the 5d centroid shift of CeLa(6h)3+ is emphasized. The thermal stability and doping concentration dependence of the 5d luminescence are also investigated and discussed in association with the coordination structures of Ce3+.

  7. Copper(II) bis [2-((E)-2-(pyrid-2-yl)ethylimino)methyl)-6-bromo-4-chlorophenolate

    SciTech Connect

    Zhang, X. L.

    2013-01-15

    A new complex CuL{sub 2} [HL = 2-((E)-(2-(pyridin-2-yl)ethylimino)methyl)-6-bromo-4-chlorophenol] was synthesized, and its structure (C{sub 28}H{sub 22}Br{sub 2}Cl{sub 2}CuN{sub 4}O{sub 2}, Mr = 740.76) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1{sup -}, with a = 5.157(6), b = 12.090(1), c =12.310(1) A, {alpha} = 113.962(2) Degree-Sign , {beta} = 96.7910(10) Degree-Sign , {gamma} = 90.0300(10) Degree-Sign , V = 695.4(8) A{sup 3}, Z = 1, R = 0.0481. The complex molecules are linked via the weak C-H...N hydrogen bonds, leading to the formation of one dimension (1D) chains along the a axis.

  8. Concentrations of Polybrominated Diphenyl Ethers (PBDEs) and 2,4,6-Tribromophenol in Human Placental Tissues

    PubMed Central

    Leonetti, Christopher; Butt, Craig M.; Hoffman, Kate; Miranda, Marie Lynn; Stapleton, Heather M.

    2015-01-01

    Legacy environmental contaminants such as polybrominated diphenyl ethers (PBDEs) are widely detected in human tissues. However, few studies have measured PBDEs in placental tissues, and there are no reported measurements of 2,4,6-tribromophenol (2,4,6-TBP) in placental tissues. Measurements of these contaminants are important for understanding potential fetal exposures, as these compounds have been shown to alter thyroid hormone regulation in vitro and in vivo. In this study, we measured a suite of PBDEs and 2,4,6-TBP in 102 human placental tissues collected between 2010–2011 in Durham County, North Carolina, USA. The most abundant PBDE congener detected was BDE-47, with a mean concentration of 5.09 ng/g lipid (range: 0.12–141 ng/g lipid; detection frequency 91%); however, 2,4,6-TBP was ubiquitously detected and present at higher concentrations with a mean concentration of 15.4 ng/g lipid (range:1.31–316 ng/g lipid; detection frequency 100%). BDE-209 was also detected in more than 50% of the samples, and was significantly associated with 2,4,6-TBP in placental tissues, suggesting they may have a similar source, or that 2,4,6-TBP may be a degradation product of BDE-209. Interestingly, BDE-209 and 2,4,6-TBP were negatively associated with age (rs=−0.16; p=0.10 and rs=−0.17; p=0.08, respectively). The results of this work indicate that PBDEs and 2,4,6-TBP bioaccumulate in human placenta tissue and likely contribute to prenatal exposures to these environmental contaminants. Future studies are needed to determine if these joint exposures are associated with any adverse health measures in infants and children. PMID:26700418

  9. Competitive solvation of K+ by C6H6 and H2O in the K+-(C6H6)n-(H2O)m (n = 1-4; m = 1-6) aggregates

    NASA Astrophysics Data System (ADS)

    Albertí, Margarita; Lago, Noelia Faginas

    2013-04-01

    The competitive solvation of the potassium ion by benzene and water is investigated at molecular level by means of Molecular Dynamics simulations on the K+-(C6H6) n -(H2O) m ( n = 1-4; m = 1-6) ionic aggregates. The preference of K+ to bind C6H6 or H2O is investigated in the range of temperatures in which isomerisation processes are likely by adding water and benzene to the K+-(C6H6) n and K+-(H2O) m aggregates, respectively. Hydrogen bonds and the π-hydrogen bond, in spite of their weakness with respect to the K+- π and K+-H2O interactions, play an important role in stabilising different isomers, thus favouring isomerisation processes. Accordingly with experimental information it has been found that K+ bind preferably C6H6 rather than H2O and that the fragmentation of C6H6 is only observed for aggregates containing four molecules of benzene.

  10. A study of radiolytic stability of 25,27-bis(2-propyloxy) calix[4]-26,28-crown-6 (iPR-C[4]C-6)

    SciTech Connect

    Jianchen, Wang; Chongli, Song

    2008-07-01

    The radiolytic stability of 25,27-bis(2-propyloxy)calix[4] arene -26,28-crown-6 (iPr-C[4]C-6) was studied. {sup 60}co was used as a radiation source. Its dose rate was 437 Gy/min., and the total absorbed dose of the iPr-C[4]C-6 was from 10{sup 4} to 10{sup 6} Gy. The iPr-C[4]C-6 solid and 0.025 mol/L iPr-C[4]C-6/n-octanol which were pre-equilibrated with 0.01 mol/L and 3 mol/L nitric acid, respectively, were given different doses, and their extraction performance was researched. Their degradation mechanism was investigated by mass spectrometry (MS) and infrared spectroscopy (IR). The results show that radiolytic stability of the iPr-C[4]C-6 solid and 0.025 mol/L iPr-C[4]C-6/n-octanol are good when their absorbed dose is less than 10{sup 6} Gy. The extracting system of iPr-C[4]C-6/n-octanol is promising for separating cesium from high-level liquid waste(HLLW)

  11. Propellant Containing 3, 6bis(1h-1,2,3,4-Tetrazol-5-Ylamino)-1,2,4,5- Tetrazine Or Salt Thereof

    DOEpatents

    Hiskey, Michael A.; Chavez, David E.; Naud, Darren

    2003-12-02

    The compound 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine and its salts are provided together with a propellant composition including an oxidizer, a binder and 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine or its salts.

  12. COMPARISON OF BIOMARKERS IN WORKERS EXPOSED TO 2,4,6-TRINITROTOLUENE

    EPA Science Inventory

    2,4,6-Trinitrotoluene (TNT) is an important occupational and environmental pollutant. In TNT-exposed humans, the notable toxic manifestations have included aplastic anemia, toxic hepatitis, cataracts, hepatomegaly, and liver cancer. Therefore, we developed methods to biomonitor w...

  13. Mechanism of bioactivation and covalent binding of 2,4,6-trinitrotoluene.

    PubMed

    Leung, K H; Yao, M; Stearns, R; Chiu, S H

    1995-06-30

    Studies were undertaken to investigate the mechanism of bioactivation and covalent binding of TNT. Incubation of [14C]TNT with rat liver microsomes in the presence of an NADPH generating system resulted in metabolism and covalent binding to microsomal proteins. Time-dependence studies showed that TNT was rapidly reduced to yield 4-hydroxylamino-2,6-dinitrotoluene (4HA), 4-amino-2,6-dinitrotoluene (4A) and 2-amino-4,6-dinitrotoluene (2A) as intermediates which were further metabolized to form 2,4-diamino-6-nitrotoluene (2,4DA) and 2,6-diamino-4-nitrotoluene (2,6DA). In contrast to the rapid disappearance of TNT, formation of covalent protein adducts increased with time, suggesting that the reactive intermediate was likely to be formed not directly from TNT but from proximal intermediates such as 4HA. The hypothesis that 4HA was more readily converted to the reactive intermediate than TNT was further supported by the increased levels of covalent adduct formation when [14C]4HA was incubated directly with liver microsomes. Covalent binding of TNT and 4HA was dependent on oxygen concentration. Higher levels of covalent adducts were formed when TNT was incubated aerobically (up to 50% oxygen concentration) than under anaerobic conditions. Covalent binding of [14C]4HA also increased with increasing oxygen concentrations. These results suggest that the reactive intermediate is likely to be an oxidized metabolite of 4HA, e.g. 4-nitroso-2,6-dinitrotoluene. Compounds containing a free sulfhydryl group (cysteine, N-acetylcysteine, GSH or 3,4-dichlorobenzenethiol) decreased the amount of covalent binding to various degrees, suggesting the involvement of the sulfhydryl group in adduct formation with TNT following bioactivation. Metabolic activation of TNT by liver microsomes required NADPH but not NADH as the cofactor. Incubation of [14C]TNT with purified rat liver NADPH cytochrome P450 reductase under either aerobic or anaerobic conditions yielded exclusively 4HA. In contrast

  14. Chiral pyridin-3-ones and pyridines: syntheses of enantiopure 2,4-disubstituted 6-hydroxy-1,6-dihydro-2H-pyridin-3-ones, 2,3-disubstituted 4-iodopyridines, and enantiopure 2,3-disubstituted 4-pyridinemethanols.

    PubMed

    Husain, Irfan; Saquib, Mohammad; Bajpai, Vikas; Kumar, Brijesh; Shaw, Arun K

    2011-11-04

    The development of an innovative method to access enantiopure 2,4-disubstituted 6-hydroxy-1,6-dihydro-2H-pyridin-3-ones starting from D-glucal via the aza-Achmatowicz transformation has been described. These highly functionalized pyridin-3-ones have been utilized for the synthesis of contiguously substituted pyridines through a rapid and efficient Et(3)N/Ac(2)O promoted cyclo-elimination, aromatization cascade, allowing the facile assembly of important pyridine-based building blocks like 2-substituted 3-acetoxy-4-iodopyridines and enantiopure 2-substituted 3-acetoxy-4-pyridinemethanols possessing benzylic stereogenic centers, whose synthesis otherwise would be tedious. The utilization of commercially available sugars as starting materials, mild reaction conditions, catalytic transfer hydrogen (CTH) of α-furfuryl azide derivatives, transfer of chiral aryl/alkyl methanols from enulosides to pyridin-3-ones and pyridines, high yields, and short reaction times are key features of this method. The utility of the method has been further exemplified by demonstrating the usage of the 2-substituted 3-acetoxy-4-iodopyridine for the construction of biologically significant molecules like 2,7-disubstituted furo[2,3-c]pyridines and 7,7'-disubstituted 2,2'-bifuro[2,3-c]pyridines.

  15. Anaerobic transformation of 2,4,6-TNT by bovine ruminal microbes.

    PubMed

    Fleischmann, Thomas J; Walker, Karen C; Spain, Jim C; Hughes, Joseph B; Morrie Craig, A

    2004-02-20

    Degradation of TNT by bovine rumen fluid, a novel source of anaerobic microbes, was investigated. Whole rumen fluid contents were spiked with TNT and incubated for a 24h time period. Supernatant samples taken at 0, 1, 2, 4, and 24h were analyzed by reverse-phase HPLC with diode array detection. Within 1h, TNT was not detectable and reduction products of TNT including 2-hydroxyl-amino-4,6-dinitrotoluene, 4-hydroxylamino-2,6-dinitrotoluene, and 4-amino-2,6-dinitrotoluene were present with smaller amounts of diamino-nitrotoluenes. Within 2h, only the diamino and dihydroxyamino-nitrotoluene products remained. After 4h, 2,4-diamino-6-nitrotoluene and 2,4-dihydroxyamino-6-nitrotoluene were the only known molecular species left. At 24h known UV absorbing metabolites were no longer detected, suggesting further transformation such as complete reduction to triaminotoluene or destruction of the aromatic ring of TNT may have occurred. TNT was not transformed at 24h in autoclaved and buffered controls. This study presents the first direct evidence of biodegradation of TNT by ruminal microbes.

  16. Structural and theoretical characterization of a new twisted 4'-substituted terpyridine compound: 4'-(isoquinolin-4-yl)-2,2':6',2''-terpyridine.

    PubMed

    Granifo, Juan; Arévalo, Beatriz; Gaviño, Rubén; Suárez, Sebastián; Baggio, Ricardo

    2016-12-01

    4'-Substituted derivatives of 2,2':6',2''-terpyridine with N-containing heteroaromatic substituents, such as pyridyl groups, might be able to coordinate metal centres through the extra N-donor atom, in addition to the chelating terpyridine N atoms. The incorporation of these peripheral N-donor sites would also allow for the diversification of the types of noncovalent interactions present, such as hydrogen bonding and π-π stacking. The title compound, C24H16N4, consists of a 2,2':6',2''-terpyridine nucleus (tpy), with a pendant isoquinoline group (isq) bound at the central pyridine (py) ring. The tpy nucleus deviates slightly from planarity, with interplanar angles between the lateral and central py rings in the range 2.24 (7)-7.90 (7)°, while the isq group is rotated significantly [by 46.57 (6)°] out of this planar scheme, associated with a short Htpy...Hisq contact of 2.32 Å. There are no strong noncovalent interactions in the structure, the main ones being of the π-π and C-H...π types, giving rise to columnar arrays along [001], further linked by C-H...N hydrogen bonds into a three-dimensional supramolecular structure. An Atoms In Molecules (AIM) analysis of the noncovalent interactions provided illuminating results, and while confirming the bonding character for all those interactions unquestionable from a geometrical point of view, it also provided answers for some cases where geometric parameters are not informative, in particular, the short Htpy...Hisq contact of 2.32 Å to which AIM ascribed an attractive character.

  17. Disappearance of superconductivity in the solid solution between (Ca4Al2O6)(Fe2As2) and (Ca4Al2O6)(Fe2P2) superconductors.

    PubMed

    Shirage, Parasharam M; Kihou, Kunihiro; Lee, Chul-Ho; Takeshita, Nao; Eisaki, Hiroshi; Iyo, Akira

    2012-09-19

    The effect of alloying the two perovskite-type iron-based superconductors (Ca(4)Al(2)O(6))(Fe(2)As(2)) and (Ca(4)Al(2)O(6))(Fe(2)P(2)) was examined. While the two stoichiometric compounds possess relatively high T(c)'s of 28 and 17 K, respectively, their solid solutions of the form (Ca(4)Al(2)O(6))(Fe(2)(As(1-x)P(x))(2)) do not show superconductivity over a wide range from x = 0.50 to 0.95. The resultant phase diagram is thus completely different from those of other typical iron-based superconductors such as BaFe(2)(As,P)(2) and LaFe(As,P)O, in which superconductivity shows up when P is substituted for As in the non-superconducting "parent" compounds. Notably, the solid solutions in the non-superconducting range exhibit resistivity anomalies at temperatures of 50-100 K. The behavior is reminiscent of the resistivity kink commonly observed in various non-superconducting parent compounds that signals the onset of antiferromagnetic/orthorhombic long-range order. The similarity suggests that the suppression of the superconductivity in the present case also has a magnetic and/or structural origin.

  18. 2,4,6-Tris(2,2,2-trinitroethylamino)-1,3,5-triazine: Synthesis, Characterization, and Energetic Properties

    NASA Astrophysics Data System (ADS)

    Li, Shenghua; Zhang, Weiwei; Wang, Yuan; Zhao, Xiuxiu; Zhang, Lubo; Pang, Siping

    2014-05-01

    A simple and straightforward route for the synthesis of 2,4,6-tris(2,2,2-trinitroethylamino)-1,3,5-triazine (TTET) has been developed. The compound was fully characterized by multinuclear (1H, 13C) magnetic resonance and infrared (IR) spectroscopy, elemental analysis, electron ionization-mass spectrometry, and differential scanning calorimetry (DSC). TTET was found to have good physical properties, such as good thermal stability (Td = 186°C), reasonable impact sensitivity (21.5 J), and high density (1.88 g . cm-3). Additionally, the detonation properties of TTET obtained with the empirical Kamlet-Jacobs equations identify it as a competitively energetic compound, which in some cases is superior to 1,3,5-Trinitroperhydro-1,3,5-triazine.

  19. Feeding of [5,5-2H(2)]-1-desoxy-D-xylulose and [4,4,6,6,6-2H(5)]-mevalolactone to a geosmin-producing Streptomyces sp. and Fossombronia pusilla.

    PubMed

    Spiteller, Dieter; Jux, Andreas; Piel, Jörn; Boland, Wilhelm

    2002-12-01

    The biosynthesis of the trisnor sesquiterpenoid geosmin (4,8a-dimethyl-octahydro-naphthalen-4a-ol) (1) was investigated by feeding labeled [5,5-2H(2)]-1-desoxy-D-xylulose (11), [4,4,6,6,6-(2)H(5)]-mevalolactone (7) and [2,2-2H(2)]-mevalolactone (9) to Streptomyces sp. JP95 and the liverwort Fossombronia pusilla. The micro-organism produced geosmin via the 1-desoxy-D-xylulose pathway, whereas the liverwort exclusively utilized mevalolactone for terpenoid biosynthesis. Analysis of the labeling pattern in the resulting isotopomers of geosmin (1) by mass spectroscopy (EI/MS) revealed that geosmin is synthesized in both organisms by cyclization of farnesyl diphosphate to a germacradiene-type intermediate 4. Further transformations en route to geosmin (1) involve an oxidative dealkylation of an i-propyl substituent, 1,2-reduction of a resulting conjugated diene, and bicyclization of a germacatriene intermediate 13. The transformations largely resemble the biosynthesis of dehydrogeosmin (2) in cactus flowers but differ with respect to the regioselectivity of the side chain dealkylation and 1,2-reduction

  20. Vicarious nucleophilic substitution using 4-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxylamine to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, A.R.; Pagoria, P.F.; Schmidt, R.D.

    1997-05-27

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0 and 50 C for between about 0.1 and 24 hr, a trinitroaromatic compound of the structure shown where X, Y, and Z are each independently selected from the group consisting of -H and -NH{sub 2}, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen; with an effective amount of 1-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxamine to produce DATB or TATB; in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present or when hydroxylamine or its O-alkyl derivatives replace ATA primarily DATB is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are important and useful specialty explosives and intermediates for other materials.

  1. Vicarious nucleophilic substitution using 4-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxylamine to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, Alexander R.; Pagoria, Philip F.; Schmidt, Robert D.

    1997-01-01

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,-trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0.degree. and 50.degree. C. for between about 0.1 and 24 hr, a trinitroaromatic compound of structure V: ##STR1## wherein X, Y, and Z are each independently selected from the group consisting of --H and --NH.sub.2, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen; with an effective amount of 1-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxamine to produce DATB or TATB; in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present or when hydroxylamine or its O-alkyl derivatives replace ATA primarily DATB is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are important and useful specialty explosives and intermediates for other materials.

  2. Crystal structure of poly[[μ3-4,4'-(4,4'-bipyridine-2,6-diyl)dibenzoato]{μ2-4-[6-(4-carboxyphenyl)-4,4'-bipyridin-4'-ium-2-yl]benzoato}manganese(II)] hemi-hydrate].

    PubMed

    Li, Yaping; Sun, Dajun; Ming, Julia; Han, Liying; Su, Guanfang

    2014-11-01

    The title compound, {[Mn(C24H14N2O4)(C24H16N2O4)]·0.5H2O} n , was obtained by the reaction of manganese nitrate with the ligand 4,4'-(4,4'-bi-pyridine-2,6-di-yl) di-benzoic acid under hydro-thermal conditions. The water O atom is located on a twofold rotation axis. The Mn(2+) ion is hepta-coordinated by six O atoms and one N atom from the ligands. In this structure, the ligands adopts two different forms, one completely deprotonated and one with a protonated N atom (pyridinium) and a carboxylic acid function. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds consolidate the packing, forming a three-dimensional framework.

  3. Electronic, magnetic properties and chemical bonding in layered oxychalcogenides Ca4Fe2Cu2S2O6 and Ca4Fe2Cu2Se2O6 from first principles calculations

    NASA Astrophysics Data System (ADS)

    Suetin, D. V.; Ivanovskii, A. L.

    2012-10-01

    The crystal structure, electronic, magnetic properties and inter-atomic bonding in recently synthesized five-component Fe-containing oxychalcogenides Ca4Fe2Cu2Ch2O6, where Ch are S or Se, which unlike all other related materials contain Fe atoms in 2D perovskite-like oxide blocks (Ca4Fe2O6), were probed by means of first-principle FLAPW-GGA calculations. We found that these materials can be characterized as antiferromagnetic ionic semiconductors, composed of alternating non-magnetic chalcogenide blocks (Cu2Ch2) and antiferromagnetic oxide blocks (Ca4Fe2O6) with S-AFM spin configuration for Fe sublattice; the interaction between these building blocks is ionic. Moreover, our results reveal that for these materials the formation of "natural multiple quantum wells" can be expected — like it has been found for more simple four-component LnCuOCh phases. This feature (unique for five-component Fe-containing phases) originates from 2D density of states and quantum size effects in these layered materials.

  4. Comparative analysis of P2Y4 and P2Y6 receptor architecture in native and transfected neuronal systems.

    PubMed

    D'Ambrosi, Nadia; Iafrate, Monia; Saba, Elena; Rosa, Patrizia; Volonté, Cinzia

    2007-06-01

    Although extensive studies provided molecular and pharmacological characterization of metabotropic P2Y receptors for extracellular nucleotides, little is still known about their quaternary structure. By the use of transfected cellular systems and SDS-PAGE, in our previous work we established the propensity of P2Y(4) receptor to form dimeric interactions. Here we focused on endogenously expressed P2Y(4) and P2Y(6) subtypes, comparing their oligomeric complexes under Blue Native (BN) gel electrophoresis. We provided evidence that P2Y(4) and P2Y(6) receptors form high order complexes in native neuronal phenotypes and that the oligomers can be disaggregated down to the dimeric P2Y(4) or to the dimeric and monomeric P2Y(6) receptor. Moreover, dimeric P2Y(4) and monomeric P2Y(6) proteins display selective microdomain partitioning in lipid rafts from specialized subcellular compartments such as synaptosomes. Ligand activation by UTP shifted the oligomerization of P2Y(6) but not of P2Y(4) receptor, as analysed by BN electrophoresis. Finally, whereas transfected P2Y(4) and P2Y(6) proteins homo-interact and posses the appropriate domains to associate with all P2Y(1,2,4,6,11) subtypes, in naive PC12 cells the endogenous P2Y(4) forms hetero-oligomers only with the P2Y(6) subunit. In conclusion, our results indicate that quaternary structure distinguishing P2Y(4) from P2Y(6) receptors might be crucial for specific ligand activation, membrane partitioning and consequent functional regulation.

  5. Vicarious nucleophilic substitution to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, Alexander R.; Pagoria, Philip F.; Schmidt, Robert D.

    1996-01-01

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,-trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0.degree. and 50.degree. C. for between about 0.1 and 24 hr, a trinitroaromatic compound of structure V: ##STR1## wherein X, Y, and Z are each independently selected from --H, or --NH.sub.2, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen, with an amount effective to produce DATB or TATB of 1,1,1-trialkylhydrazinium halide wherein alkyl is selected from methyl, ethyl, propyl or butyl and halide is selected from chloride, bromide or iodide. in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present primarily DATB and picramide is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are useful specialty explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).

  6. Vicarious nucleophilic substitution to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, A.R.; Pagoria, P.F.; Schmidt, R.D.

    1996-10-29

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0 and 50 C for between about 0.1 and 24 hr, a trinitroaromatic compound of the structure shown within where X, Y, and Z are each independently selected from --H, or --NH{sub 2}, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen, with an amount effective to produce DATB or TATB, or 1,1,1-trialkylhydrazinium halide wherein alkyl is selected from methyl, ethyl, propyl or butyl and halide is selected from chloride, bromide or iodide, in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulfoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present primarily DATB and picramide is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are useful specialty explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).

  7. Transformation of 2,4,6-Trinitrotoluene by Pseudomonas pseudoalcaligenes JS52.

    PubMed

    Fiorella, P D; Spain, J C

    1997-05-01

    Pseudomonas pseudoalcaligenes JS52 grows on nitrobenzene via partial reduction of the nitro group and enzymatic rearrangement of the resultant hydroxylamine. Cells and cell extracts of nitrobenzene-grown JS52 catalyzed the transient formation of 4-hydroxylamino-2,6-dinitrotoluene (4HADNT), 4-amino-2,6-dinitrotoluene (4ADNT), and four previously unidentified metabolites from 2,4,6-trinitrotoluene (TNT). Two of the novel metabolites were identified by liquid chromatography/mass spectrometry and (sup1)H-nuclear magnetic resonance spectroscopy as 2,4-dihydroxylamino-6-nitrotoluene (DHANT) and 2-hydroxylamino-4-amino-6-nitrotoluene (2HA4ANT). A polar yellow metabolite also accumulated during transformation of TNT by cells and cell extracts. Under anaerobic conditions, extracts of strain JS52 did not catalyze the production of the yellow metabolite or release nitrite from TNT; moreover, DHANT and 2HA4ANT accumulated under anaerobic conditions, which indicated that their further metabolism was oxygen dependent. Small amounts of nitrite were released during transformation of TNT by strain JS52. Sustained transformation of TNT by cells required nitrobenzene, which indicated that TNT transformation does not provide energy. Transformation of TNT catalyzed by enzymes in cell extracts required NADPH. Transformation experiments with (sup14)C-TNT indicated that TNT was not mineralized; however, carbon derived from TNT became associated with cells. Nitrobenzene nitroreductase purified from strain JS52 transformed TNT to DHANT via 4HADNT, which indicated that the nitroreductase could catalyze the first two steps in the transformation of TNT. The unusual ability of the nitrobenzene nitroreductase to catalyze the stoichiometric reduction of aromatic nitro compounds to the corresponding hydroxylamine provides the basis for the novel pathway for metabolism of TNT.

  8. Transformation of 2,4,6-Trinitrotoluene by Pseudomonas pseudoalcaligenes JS52

    PubMed Central

    Fiorella, P. D.; Spain, J. C.

    1997-01-01

    Pseudomonas pseudoalcaligenes JS52 grows on nitrobenzene via partial reduction of the nitro group and enzymatic rearrangement of the resultant hydroxylamine. Cells and cell extracts of nitrobenzene-grown JS52 catalyzed the transient formation of 4-hydroxylamino-2,6-dinitrotoluene (4HADNT), 4-amino-2,6-dinitrotoluene (4ADNT), and four previously unidentified metabolites from 2,4,6-trinitrotoluene (TNT). Two of the novel metabolites were identified by liquid chromatography/mass spectrometry and (sup1)H-nuclear magnetic resonance spectroscopy as 2,4-dihydroxylamino-6-nitrotoluene (DHANT) and 2-hydroxylamino-4-amino-6-nitrotoluene (2HA4ANT). A polar yellow metabolite also accumulated during transformation of TNT by cells and cell extracts. Under anaerobic conditions, extracts of strain JS52 did not catalyze the production of the yellow metabolite or release nitrite from TNT; moreover, DHANT and 2HA4ANT accumulated under anaerobic conditions, which indicated that their further metabolism was oxygen dependent. Small amounts of nitrite were released during transformation of TNT by strain JS52. Sustained transformation of TNT by cells required nitrobenzene, which indicated that TNT transformation does not provide energy. Transformation of TNT catalyzed by enzymes in cell extracts required NADPH. Transformation experiments with (sup14)C-TNT indicated that TNT was not mineralized; however, carbon derived from TNT became associated with cells. Nitrobenzene nitroreductase purified from strain JS52 transformed TNT to DHANT via 4HADNT, which indicated that the nitroreductase could catalyze the first two steps in the transformation of TNT. The unusual ability of the nitrobenzene nitroreductase to catalyze the stoichiometric reduction of aromatic nitro compounds to the corresponding hydroxylamine provides the basis for the novel pathway for metabolism of TNT. PMID:16535610

  9. Material characterization of superplastically formed titanium (Ti-6Al-2Sn-4Zr-2Mo) sheet

    NASA Technical Reports Server (NTRS)

    Ossa, William A.; Royster, Dick M.

    1987-01-01

    The aerospace industry has focused considerable interest on the near-alpha titanium alloy Ti-6Al-2Sn-4Zr-2Mo (Ti-6242) because of both its high-temperature properties and its superplastic forming (SPF) capabilities. This paper describes current research to characterize selected mechanical properties of Ti-6242 sheet in the SPF-strained condition, both with and without heat treatment, and compares the results with those obtained on as-received material. Tensile and creep tests were conducted, and metallographic analysis was performed to show the effect of 100 to 700 percent SPF strain on titanium properties. Analysis shows that as a result of SPF processing, both tensile and yield strengths, as well as elongation, are moderately reduced. Creep tests at 800 F and 1000 F show that the SPF processed material displays superior creep resistance compared with the as-received material. A post-SPF duplex-anneal heat treatment had no beneficial effect on tensile and creep properties.

  10. Adipic acid-2,6-bis-(1H-benzimidazol-2-yl)pyridine-water (1/2/4).

    PubMed

    Lin, Songzhu; Jia, Ruokun; Gao, Feng; Zhou, Xiaoqing

    2012-12-01

    The asymmetric unit of the title hydrated co-crystal, 2C19H13N5·C6H10O4·4H2O, consists of one 2,6-bis-(1H-benzimidazol-2-yl)pyridine mol-ecule, half of an adipic acid mol-ecule (bis-ected by an inversion center) and two water solvates. In the crystal, N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds and π-π inter-actions [centroid-centroid distances = 3.769 (2) and 3.731 (2) Å] form a three-dimensional supra-molecular structure.

  11. [V16Sb4O42(H2O){VO(C6H14N2)2}4]: a terminal expansion to a polyoxovanadate archetype.

    PubMed

    Wutkowski, Adam; Näther, Christian; Kögerler, Paul; Bensch, Wolfgang

    2008-03-17

    The charge-neutral antimonatopolyoxovanadium(IV) cluster [V(IV)16Sb(III)4O42(H2O){V(IV)O(C6H14N2)2}4].10H2O.C6H14N2 was obtained under solvothermal conditions. The central cluster fragment, [V(IV) 16Sb(III)4O42], is a derivative of the [V18O42] archetype and is formed by replacing two VO5 polyhedra by two Sb2O5 units. The {V20Sb4} structure expands the {V16Sb4} motif by the addition of four square-pyramidal, terminal VO(1,2-diaminocyclohexane)2 groups. At low temperatures, the magnetic ground state is characterized by four independent S = 1/2 sites.

  12. (4E)-dehydrocitrals [(2E,4E)- and (2Z,4E )-3,7-dimethyl-2,4,6-octatrienals] from acarid mite Histiogaster sp. A096 (Acari: Acaridae).

    PubMed

    Hiraoka, H; Mori, N; Nishida, R; Kuwahara, Y

    2001-12-01

    A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be (4E)-dehydrocitrals [(2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienals] by GC/MS, GC/FT-IR, UV and 1H-NMR spectra. Both isomers of (4E)-dehydrocitral prepared by syntheses in 4 steps from 3-methyl-2-butenal with 34.2% yields (based on the ylide) were separated by column chromatography into the (2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. Mass spectra together with GC retention times of the purified natural (4E)-dehydrocitrals were identical with those of synthetic (2E,4E)-3,7-dimethyl-2,4,6-octatrienal and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. The geometry at the 2-C position of both synthetic (4E)-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of (4E)-dehydrocitrals from the animal kingdom.

  13. Crystal structures of the water and acetone monosolvates of bis-[4'-(pyridin-4-yl)-2,2':6',2''-terpyridine]-manganese(II) bis-(hexa-fluorido-phosphate).

    PubMed

    Lourenço, Leandro M O; Almeida Paz, Filipe A; Fernandes, José A

    2015-04-01

    The crystal structures of bis-[4'-(pyridin-4-yl)-2,2':6',2''-terpyridine]-man-gan-ese(II) bis-(hexa-fluorido-phosphate) monohydrate, [Mn(C20H14N4)2](PF6)2·H2O, (1), and bis-[4'-(pyridin-4-yl)-2,2':6',2''-terpyridine]-manganese(II) bis(hexa-fluorido-phosphate) acetone monosolvate, (2), [Mn(C20H14N4)2](PF6)2·CH3COCH3, are described. At 150 K, (1) and (2) have monoclinic (P21/c) and ortho-rhom-bic (C2221) symmetries, respectively. Both structures exhibit octahedrally coordinated Mn(II) atoms and disorder. They display weak inter-actions, such as C-H⋯F, C-H⋯N, C-H⋯π, F⋯π and π-π. The twofold rotation axis in the molecule of (2) is coincident with a twofold rotation axis of the crystal.

  14. Structural stability, NH 2 inversion and vibrational assignments of 2,4,6-trichloroaniline and 2,3,5,6-tetrachloroaniline

    NASA Astrophysics Data System (ADS)

    Badawi, Hassan M.; Förner, Wolfgang; Al-Saadi, Abdulaziz A.

    2009-12-01

    The structural stability of aniline, 2,4,6-trichloroaniline and 2,3,5,6-tetrachloroaniline was investigated by DFT-B3LYP and ab initio MP2 and MP4(SDQ) calculations with the 6-311G∗∗ basis set. From the calculations the three molecules were predicted to exist predominantly in a symmetric near-planar structure. The NH 2 inversion barrier was estimated from the MP2/6-311G∗∗ level of theory to be about 9.6 kJ/mol for aniline, 5.9 kJ/mol for the trichloro and 4.6 kJ/mol for the tetrachloro derivatives. The line intensities of the ring breathing and the C sbnd Cl stretching modes were shown to have a great dependence on the number of chlorine atoms on the benzene ring. The relative change in Raman line intensity of the C sbnd Cl stretching mode was explained on the basis of the inductive effect of the chlorine atoms on the benzene ring. The vibrational frequencies were computed at the DFT-B3LYP level and the infrared and Raman spectra for each molecule were calculated. Complete vibrational assignments were made on the basis of normal coordinate analyses and potential energy distributions for the two chloroanilines.

  15. Incorporating Small Fatigue Crack Growth in Probabilistic Life Prediction: Effect of Stress Ratio in Ti-6Al-2Sn-4Zr-6-Mo (Preprint)

    DTIC Science & Technology

    2012-08-01

    growth rates as well as the variability in the same, in the + titanium alloy, Ti-6Al-2Sn-4Zr-6Mo (Ti- 6 -2- 4 - 6 ) was studied at 260°C. A probabilistic...were obtained in a separate study on the effect of R on the small-crack growth regime in another + titanium alloy, Ti- 6 - 4 [32]. Given that crack...microstructure of Ti-6Al-2Sn-4Zr-6Mo (Ti- 6 -2- 4 - 6 ) at 260°C with particular emphasis on incorporating small-crack data into probabilistic life prediction

  16. Occurrence of earthy and musty odor compounds (geosmin, 2-methylisoborneol and 2,4,6-trichloroanisole) in biologically treated wastewater.

    PubMed

    Urase, T; Sasaki, Y

    2013-01-01

    The concentrations of earthy and musty odor compounds (2-methylisoborneol (2-MIB), geosmin and 2,4,6-trichloroanisole (TCA)) in treated wastewater were measured. Concentrations of 2,4,6-TCA (4.3-37.7 ng/L) and geosmin (3.7-42.2 ng/L) higher than their odor thresholds were detected for effluents from large-scale treatment plants. The effluent from a small-scale wastewater plant treating toilet and kitchen wastewater contained the target earthy and musty odor compounds below the odor thresholds. The ozonation applied as an advanced wastewater treatment process was considerably more effective for the removal of 2,4,6-TCA than for the removal of 2-MIB and geosmin. The measured concentrations of 2,4,6-TCA in river environments without the influence of large-scale wastewater effluents were less than the odor threshold.

  17. Independent movement of the voltage sensors in KV2.1/KV6.4 heterotetramers

    PubMed Central

    Bocksteins, Elke; Snyders, Dirk J.; Holmgren, Miguel

    2017-01-01

    Heterotetramer voltage-gated K+ (KV) channels KV2.1/KV6.4 display a gating charge-voltage (QV) distribution composed by two separate components. We use state dependent chemical accessibility to cysteines substituted in either KV2.1 or KV6.4 to assess the voltage sensor movements of each subunit. By comparing the voltage dependences of chemical modification and gating charge displacement, here we show that each gating charge component corresponds to a specific subunit forming the heterotetramer. The voltage sensors from KV6.4 subunits move at more negative potentials than the voltage sensors belonging to KV2.1 subunits. These results indicate that the voltage sensors from the tetrameric channels move independently. In addition, our data shows that 75% of the total charge is attributed to KV2.1, while 25% to KV6.4. Thus, the most parsimonious model for KV2.1/KV6.4 channels’ stoichiometry is 3:1. PMID:28139741

  18. Microbial Transformation of 2,4,6-Trinitrotoluene in Aerobic Soil Columns

    PubMed Central

    Bruns-Nagel, D.; Breitung, J.; von Low, E.; Steinbach, K.; Gorontzy, T.; Kahl, M.; Blotevogel, K.; Gemsa, D.

    1996-01-01

    2,4,6-Trinitrotoluene (TNT)-contaminated soil material of a former TNT production plant was percolated aerobically in soil columns. Nineteen days of percolation with a potassium phosphate buffer supplemented with glucose or glucose plus ammonium sulfate caused an over 90% decline in the amount of extractable nitroaromatics in soils containing 70 to 2,100 mg of TNT per kg (dry weight). In the percolation solution, a complete elimination of TNT was achieved. Mutagenicity and soil toxicity were significantly reduced by the percolation process. 4-N-Acetylamino-2-amino-6-nitrotoluene was generated in soil and percolation fluid as a labile TNT metabolite. PMID:16535369

  19. 2,3,4,6-Tetrachlorophenyl esters as antiseptics for fibrous materials

    SciTech Connect

    Stepanenko, N.I.; Ryakhovskaya, A.I.; Romanenko, O.A.; Garifullina, K.R.

    1983-09-10

    Wastes containing tri- and tetrachlorobenzenes are obtained during production of di- and trichlorobenzenes. One way of utilizing these wastes is conversion into di- and trichlorophenols by saponification. Chlorination of a mixture of di- and trichlorophenols converts it into 2,3,4,6-tetrachlorophenol with high yields (95-96 wt. %). The uses of tetrachlorophenol are limited by its strong specific odor and volatility. The possibility of obtaining esters of 2,3,4,6-tetrachlorophenol and saturated aliphatic C/sub 2/-C/sub 12/ monocarboxylic acids, which have good antiseptic properties in relation to fibrous materials are described.

  20. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  1. Study of alpha-case depth in Ti-6Al-2Sn-4Zr-2Mo and Ti-6Al-4V

    NASA Astrophysics Data System (ADS)

    Gaddam, R.; Sefer, B.; Pederson, R.; Antti, M.-L.

    2013-12-01

    At temperatures exceeding 480°C titanium alloys generally oxidises and forms a hard and brittle layer enriched with oxygen, which is called alpha case. This layer has negative effects on several mechanical properties and lowers the tensile ductility and the fatigue resistance. Therefore any alpha-case formed on titanium alloys during various manufacturing processes, such as heat treatment procedures, must be removed before the final part is mounted in an engine. In addition, long time exposure at elevated temperatures during operation of an engine could possibly also lead to formation of alpha-case on actual parts, therefore knowledge and understanding of the alpha-case formation and its effect on mechanical properties is important. Factors that contribute for growth of alpha-case are: presence of oxygen, exposure time, temperature and pressure. In the present study, isothermal oxidation experiments in air were performed on forged Ti-6Al-2Sn-4Zr-2Mo at 500°C and 593°C up to 500 hours. Similar studies were also performed on Ti-6Al-4V plate at 593°C and 700°C. Alpha-case depth for both alloys was quantified using metallography techniques and compared.

  2. Comprehensive investigations of kinetics of alkaline hydrolysis of TNT (2,4,6-trinitrotoluene), DNT (2,4-dinitrotoluene), and DNAN (2,4-dinitroanisole).

    PubMed

    Sviatenko, Liudmyla; Kinney, Chad; Gorb, Leonid; Hill, Frances C; Bednar, Anthony J; Okovytyy, Sergiy; Leszczynski, Jerzy

    2014-09-02

    Combined experimental and computational techniques were used to analyze multistep chemical reactions in the alkaline hydrolysis of three nitroaromatic compounds: 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), and 2,4-dinitroanisole (DNAN). The study reveals common features and differences in the kinetic behavior of these compounds. The analysis of the predicted pathways includes modeling of the reactions, along with simulation of UV-vis spectra, experimental monitoring of reactions using LC/MS techniques, development of the kinetic model by designing and solving the system of differential equations, and obtaining computationally predicted kinetics for decay and accumulation of reactants and products. Obtained results suggest that DNT and DNAN are more resistant to alkaline hydrolysis than TNT. The direct substitution of a nitro group by a hydroxide represents the most favorable pathway for all considered compounds. The formation of Meisenheimer complexes leads to the kinetic first-step intermediates in the hydrolysis of TNT. Janovsky complexes can also be formed during hydrolysis of TNT and DNT but in small quantities. Methyl group abstraction is one of the suggested pathways of DNAN transformation during alkaline hydrolysis.

  3. 1-(2’,4’,6’-Trinitrophenyl)imidazoles and -1,2,4-triazoles as Energetic Materials

    DTIC Science & Technology

    1994-03-01

    triazoles and involved condensation of phenyl hydrazine hydrochloride (30) with dicyandiamide (31) to give 3,5-diamino-l-phenyl-1,2,4-triazole (32) (Reference...the presence of nitro groups on the phenyl ring hinders the condensation of the hydrazine with dicyandiamide , and while the 2’- and 4...8217-nitrophenyldiaminotriazoles (34) and (35) may be prepared, 2,4-dinitrophenyl-hydrazine was inert to reaction with dicyandiamide . Furthermore, oxidation of 34

  4. Thermal decomposition study of Mo0.6W0.4Se2 single crystals

    NASA Astrophysics Data System (ADS)

    Chaki, Sunil H.; Deshpande, M. P.; Tailor, Jiten P.

    2013-06-01

    The Mo0.6W0.4Se2 single crystals were grown by direct vapour transport (DVT) technique. The thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential thermogravimetric (DTG) analysis were carried out on the as-grown Mo0.6W0.4Se2 single crystals in inert nitrogen atmosphere. All these thermal analysis were done from ambient temperature to 1223 K. The activation energy, enthalpy, entropy and Gibbs free energy of Mo0.6W0.4Se2 single crystals were determined from the thermal curves using Broido, Horowitz-Metzger (H-M), Piloyan-Novikova (P-N) and Coats-Redfern (C-R) relations. The results are reported in this paper.

  5. Crystal structure of 4-bromo-2-[(E)-N-(2,2,6,6-tetra­methyl­piperidin-4-yl)carboximido­yl]phenol dihydrate

    PubMed Central

    Mague, Joel T.; Mohamed, Shaaban K.; Akkurt, Mehmet; Abdelhamid, Antar A.; Albayati, Mustafa R.

    2015-01-01

    In the title hydrate, C16H23BrN22H2O, the organic mol­ecule features a strong intra­molecular O—H⋯N hydrogen bond. The piperidine ring, in addition, adopts a chair conformation with the exocyclic C—N bond in an equatorial orientation. The water molecules of crystallization are disordered (each over two sets of sites with half occupancy. In the crystal, they associate into corrugated (100) sheets of (H2O)4 tetra­mers linked by O—H⋯O hydrogen bonds. The organic mol­ecules, in turn, are arranged at both sides of these sheets, linked by water–piperidine O—H⋯N hydrogen bonds. PMID:25995942

  6. Hepatic macromolecular covalent binding of the hepatocarcinogen 2,6-dinitrotoluene and its 2,4-isomer in vivo: modulation by the sulfotransferase inhibitors pentachlorophenol and 2,6-dichloro-4-nitrophenol

    SciTech Connect

    Kedderis, G.L.; Dyroff, M.C.; Rickert, D.E.

    1984-09-01

    The sulfotransferase inhibitors 2,6-dichloro-4-nitrophenol and pentachlorophenol were used to investigate the role of sulfate ester formation during the in vivo bioactivation of 2,4- and 2,6-dinitrotoluene (DNT). Male F-344 rats were administered one of the sulfotransferase inhibitors (40 mu mol/kg i.p.) 45 min prior to oral administration of 28 mg/kg (ring-14C)-2,4-DNT or (3-3H)-2,6-DNT and killed 12 h later. Pentachlorophenol had no significant effect on the urinary excretion of the benzyl glucuronide or benzoic acid metabolites of 2,6-DNT. The sulfotransferase inhibitors decreased the total hepatic macromolecular covalent binding of 2,4-DNT by 33%, and of 2,6-DNT by 69%. Purification of hepatic DNA by hydroxylapatite chromatography indicated covalent binding of 2,4- and 2,6-DNT at levels of 45 and 94 pmol equivalents/mg DNA, respectively. The sulfotransferase inhibitors decreased the binding of the hepatocarcinogen 2,6-DNT to hepatic DNA by greater than 95%. 2,6-Dichloro-4-nitrophenol decreased the binding of 2,4-DNT to DNA by greater than 84% while the decrease due to pentachlorophenol was 33%. These results suggest that sulfation is important in the biotransformation of 2,4- and 2,6-DNT to reactive metabolites which covalently bind to DNA. 3H2O was detected in the urine of rats administered (3-3H)-2,6-DNT. Pentachlorophenol decreased 3H2O formation to the same extent as it decreased the total hepatic macromolecular covalent binding of 2,6-DNT, suggesting that 3H exchange at the 3 position of 2,6-DNT occurs following sulfate ester formation. These results are consistent with a nitrenium-carbonium ion resonance of the sulfate ester-derived reactive intermediate of 2,6-DNT.

  7. Visual detection of 2,4,6-trinitrotolune by molecularly imprinted colloidal array photonic crystal.

    PubMed

    Lu, Wei; Asher, Sanford A; Meng, Zihui; Yan, Zequn; Xue, Min; Qiu, Lili; Yi, Da

    2016-10-05

    We developed a photonic crystal (PhC) sensor for the quantification of 2,4,6-trinitrotoluene (TNT) in solution. Monodisperse (210nm in diameter) molecularly imprinted colloidal particles (MICs) for TNT were prepared by the emulsion polymerization of methyl methacrylate and acrylamide in the presence of TNT as a template. The MICs were then self-assembled into close-packed opal PhC films. The adsorption capacity of the MICs for TNT was 64mg TNT/g. The diffraction from the PhC depended on the TNT concentration in a methanol/water (3/2, v/v) potassium dihydrogen phosphate buffer solution (pH=7.0, 30mM). The limit of detection (LOD) of the sensor was 1.03μg. The color of the molecularly imprinted colloidal array (MICA) changed from green to red with an 84nm diffraction red shift when the TNT concentration increased to 20mM. The sensor response time was 3min. The PhC sensor was selective for TNT compared to similar compounds such as 2,4,6-trinitrophenol, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-nitromesitylene, 4-nitrotoluene, 2-nitrotoluene, 1,3-dinitrobenzene, methylbenzene, 4-nitrophenol, 2-nitroaniline, 3-aminophenol and 3-nitroaniline. The sensor showed high stability with little response change after three years storage. This sensor technology might be useful for the visual determination of TNT.

  8. Reduction of the explosive 2,4,6-trinitrotoluene by enzymes from aquatic sediments

    SciTech Connect

    Beelen, P. van; Burris, D.R.

    1995-12-01

    Enzymes were extracted from aquatic sediments. Some of these enzymes reduced 2,4,6-trinitrotoluene (TNT) with nicotinamide adenosine dinucleotide phosphate (NADPH) as an electron donor under aerobic conditions. The origin of these enzymes was not clear as the enzymes were extracted from a sediment containing plant roots and microorganisms. Aquatic plants were determined to e a source of TNT-reducing enzymes. Chemical reduction was not a rate-limiting process in the assays as the enzymatic activity was inhibited by heating or the addition of proteases. Enzymatic activity in the extracts was further characterized. Partial purifications of enzymes from the sediment extracts shows that several proteins capable of reducing NT with NADPH were present. The enzymes did not require flavins and preferred NADPH over NADH as the electron donor. The pH optimum for the stability of the enzymes was near neutral, and the temperature optimum was in the 37 to 45 C range. Addition of dithiothreitol improved the stability of the enzymes. The enzymes reduced 2,4,6-trinitrotoluene to 2-amino-4,6-dinitrotoluene, 4-amino-2,6-dinitrotoluene, 2,4-diamino-6-nitrotoluene, and 2,6-diamino-4-nitrotoluene under aerobic conditions with NADPH. When used as a starting substrate, the aminodinitrotoluenes were not reduced by the enzymes. It might be possible that the hydroxylaminodinitrotoluenes are reduced to di[hydroxylamine]nitrotoluenes prior to the formation of the diaminonitrotoluenes. Sediments from 11 surface water bodies were examined for the presence of TNT-reducing enzymes, and 10 were found to have activity. These enzymes appear to be ubiquitous and are present in both freshwater and saltwater sediments. Reduction of TNT by sediment enzymes can be a significant environmental fate process for TNT in aquatic systems.

  9. 5,6-Dihydro-2H-1,3-dithiolo[4,5-b][1,4]dioxine-2-thione

    PubMed Central

    Wang, Guan-nan; Xiao, Xun-wen; Cai, Tongjiang; Huang, Qin

    2011-01-01

    The title mol­ecule, C5H4O2S3, consists of a planar [mean deviation = 0.020 (1) Å] 1,3-dithiole-2-thione unit with an ethyl­enedi­oxy group in the 4,5-positions. The dioxine ring is in a twist-chair conformation. PMID:21754789

  10. 5,6-Dihydro-2H-1,3-dithiolo[4,5-b][1,4]dioxine-2-thione.

    PubMed

    Wang, Guan-Nan; Xiao, Xun-Wen; Cai, Tongjiang; Huang, Qin

    2011-06-01

    The title mol-ecule, C(5)H(4)O(2)S(3), consists of a planar [mean deviation = 0.020 (1) Å] 1,3-dithiole-2-thione unit with an ethyl-enedi-oxy group in the 4,5-positions. The dioxine ring is in a twist-chair conformation.

  11. Theoretical computation of thermophysical properties of high-temperature F2, CF4, C2F2, C2F4, C2F6, C3F6 and C3F8 plasmas

    NASA Astrophysics Data System (ADS)

    Wang, WeiZong; Wu, Yi; Rong, MingZhe; Éhn, László; Černušák, Ivan

    2012-07-01

    The calculated values of thermodynamic and transport properties of pure F2 and fluorocarbon compounds CF4, C2F2, C2F4, C2F6, C3F6 and C3F8 at high temperatures are presented in this paper. The thermodynamic properties are determined by the method of Gibbs free energy minimization, using standard thermodynamic tables. The transport properties, including electron diffusion coefficients, viscosity, thermal conductivity and electrical conductivity, are evaluated using the Chapman-Enskog method expanded up to the third-order approximation (second order for viscosity). The most accurate cross-section data that could be located are used to evaluate collision integrals. The calculations based on the assumption of local thermodynamic equilibrium are performed for atmospheric-pressure plasmas in the temperature range from 300 to 30 000 K for different pressures between 0.1 and 10 atm. The results of F2, CF4, C2F2, C2F4 and C2F6 are compared with those of previously published studies. Larger discrepancies occur for transport coefficients; these are explained in terms of the different values of the collision integrals that were used. The results presented here are expected to be more accurate because of the improved collision integrals employed.

  12. N-(2,3-Dihydro-1,4-benzodioxin-6-yl)-4-fluoro-benzene-sulfonamide.

    PubMed

    Mughal, Shumaila Younas; Khan, Islam Ullah; Harrison, William T A; Khan, Muneeb Hayat; Arshad, Muhammad Nadeem

    2012-08-01

    In the title compound, C(14)H(12)FNO(4)S, the dihedral angle between the aromatic rings is 50.26 (9)° and the C-S-N-C bond adopts a gauche conformation [torsion angle = -68.12 (15)°]. The dihydro-dioxine ring is disordered over two orientations, which both approximate to half-chairs, in a 0.880 (7):0.120 (7) ratio. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains propagating in [100]. Weak C-H⋯O and C-H⋯F inter-actions consolidate the packing.

  13. [Pb(Tab)2(4,4'-bipy)](PF6)2: two-step ambient temperature quantitative solid-state synthesis, structure and dielectric properties.

    PubMed

    Wang, Fan; Ni, Chun-Yan; Liu, Quan; Li, Fu-Ling; Shi, Jing; Li, Hong-Xi; Lang, Jian-Ping

    2013-10-18

    Ambient temperature solid-state reaction of Pb(OAc)2 with TabHPF6 afforded an intermediate product [Pb(Tab)2]2(PF6)4, which further reacted with 4,4'-bipy in the solid state to generate a unique 2D cationic coordination polymer [Pb(Tab)2(4,4'-bipy)](PF6)2 in quantitative yield. Both complexes possess a low dielectric constant and low dielectric loss in the high electric field frequency range.

  14. Synthesis, stereochemical and biological studies of some N-cyclohexylcarbamoyl -2,6-diarylpiperidin-4-ones

    NASA Astrophysics Data System (ADS)

    Sethukumar, A.; Anand, P. Surendar; Kumar, C. Udhaya; Prakasam, B. Arul

    2017-02-01

    A series of N-cyclohexylcarbamoylpiperidin-4-ones were synthesized by the addition reaction of corresponding piperidin-4-ones with cyclohexylisocyanate in benzene. The structure and stereochemistry of the synthesized N-cyclohexylcarbamoyl -2, 6-diarylpiperidin-4-ones, were established on the basis of their analytical and spectral data (IR, 1H and 13C NMR). 2D NMR spectra (HOMOCOSY, HSQC, HMBC and NOESY) were also recorded to analyze the stereochemistry. In the IR spectra of synthesized compounds, the characteristic absorptions due to ring and amide carbonyl functionalities were observed which evidences the formation of N-cyclohexylcarbamoyl-2, 6-diarylpiperidin-4-ones. NMR spectral results are in line with the proposed structure of the compounds synthesized. Conformational analysis was carried out from the extracted coupling constants and NOESY spectral results. The synthesized compounds were evaluated for their antibacterial and antifungal activities.

  15. Syntheses and structures of two new M 6L i8(N 3) a6 cluster-unit based compounds: Cs 4Re 6S 8(N 3) 6·H 2O and Na 2Mo 6Br 8(N 3) 6·2H 2O

    NASA Astrophysics Data System (ADS)

    Pilet, Guillaume; Cordier, Stéphane; Golhen, Stéphane; Perrin, Christiane; Ouahab, Lahcène; Perrin, André

    2003-09-01

    The two new cluster compounds, Cs 4Re 6S 8(N 3) 6·H 2O (1) and Na 2Mo 6Br 8(N 3) 6·2H 2O (2), have been prepared via solution chemistry route, starting from the Cs 4Re 6S 8Br 6CsBr and Mo 6Br 12 precursors synthesized by solid state chemistry techniques, and structurally characterized (crystal data: Cs 4Re 6S 8(N 3) 6·H 2O (1): Orthorhombic, space group Pnam, a=10.0651(1) Å, b=15.8856(2) Å, c=20.1714(3) Å, V=3225.2(7) Å 3, Z=4, dcalc=4.48 g cm -3, μ=27.43 mm -1; Na 2Mo 6Br 8(N 3) 6·2H 2O (2): Orthorhombic, space group Ibam, a=11.5643(3) Å, b=14.3959(5) Å, c=17.0340(7) Å, V=2835.8(2) Å 3, Z=4, dcalc=3.63 g cm -3, μ=13.91 mm -1). Their structures revealed that in both cases, the M 6L i8 cluster core remains unchanged in the starting and final compounds whereas the bromine apical ligands (Br a) are substituted by N 3 azide groups leading to M 6L i8(N 3) a6 cluster unit. The new Cs 4Re 6S 8(N 3) 6·H 2O is the first example of a compound containing an octahedral rhenium cluster coordinated to azide groups.

  16. Vibrational spectra and dispersion analysis of K2Ni(SeO4)2·6H2O Tutton salt single crystal doped with K2Ni(SO4)2·6H2O

    NASA Astrophysics Data System (ADS)

    Ivanovski, Vladimir; Mayerhöfer, Thomas G.

    2013-10-01

    Dispersion analysis of the polarized IR reflectance spectra of K2Ni(SeO4)2·6H2O doped with K2Ni(SO4)2·6H2O has been performed. Vibrational parameters like oscillator strength, attenuation constant and frequency of the transversal phonons for the modes of Au symmetry type plus the orientation of the transition dipole moments for the modes of Bu symmetry type in the ac crystal plane have been obtained. The spectra-structure correlation of the H2O stretching vibrations show that bands appearing in the spectra for polarization of the external radiation oriented along the b axis are mainly due to the H2O stretching vibrations of one of the three crystallographically distinct sets of water molecules. The orientation of the transition dipoles of stretching vibrations of the selenate ion differ from the characteristic spectra of the sulfate analog in that no mutually perpendicular transition dipoles are found in the ac crystal plane. Water librational bands masked with the bands of the ν4(SO42-) mode in the sulfate analog have now been unveiled and assigned. The ratio between the oscillator strength and the attenuation constant appears to be a helpful tool in the assignment of the sulfate stretching vibrations and water librations. The vibrational and orientational characteristics of the ν4(SeO42-) modes were obtained. Тhe ν3(SO42-) frequency region of the isomorphously isolated SO42- ion in the K2Ni(SeO4)2·6H2O matrix was investigated in some detail. Contrary to the expected three, four bands can be identified. Three of them were assigned to ν3(SO42-) based on the orientation of the transition dipole moments. On the basis of the IR, but also Raman spectra of the pure and mixed crystals, a discussion of the influence of the potential field and the hydrogen bonds with the change in the volume of the unit cell is given.

  17. Transition metal complexes of the pyridylphosphine ligand o-C6H4(CH2PPy2)2.

    PubMed

    Vaughan, Teresa F; Spencer, John L

    2016-11-14

    The synthesis and coordination behaviour of the pyridylphosphine ligand o-C6H4(CH2PPy2)2 (Py = 2-pyridyl) are reported. The phosphine selenide was synthesised and the (1)JPSe value of 738 Hz indicates the phosphorus atoms have a similar basicity to PPh3. The ligand reacts with platinum(ii) and palladium(ii) complexes to give simple diphosphine complexes of the type [MX2(PP)] (M = Pt, X = Cl, I, Me, Et; M = Pd, X = Cl, Me). When the ligand is reacted with chloromethyl(hexa-1,5-diene)platinum the [PtClMe(PP)] complex results, from which a series of unsymmetrical platinum complexes of the type [PtMeL(PP)](+) (L = PPh3, PTA, SEt2 and pyridine) can be made. This enabled the comparison of the cis and trans influences of a range of ligands. The following cis influence series was compiled based on (31)P NMR data of these complexes: Py ≈ Cl > SEt2 > PTA > PPh3. Reaction of [PtClMe(PP)] with NaCH(SO2CF3)2 and carbon monoxide slowly formed an acyl complex, where the CO had inserted in the Pt-Me bond. Attempts to achieve P,P,N chelation, through abstracting the chloride ligand in [PtClMe(PP)], were unsuccessful. When the ligand reacted with platinum(0), palladium(0) and silver(i) complexes the bis-chelated complexes [M(PP)2] (M = Pt, Pd) and [Ag(PP)2](+) were formed respectively. Reaction of the ligand with [Ir(COD)(μ-Cl)]2 formed [IrCl(PP)(COD)]. When the chloride ligand was abstracted, the pyridyl nitrogens were able to interact with the iridium centre facilitating the isomerisation of the 1,2,5,6-η(4)-COD ligand to a 1-κ-4,5,6-η(3)-C8H12 ligand. The X-ray crystal structure of [Ir(1-κ-4,5,6-η(3)-C8H12)(PPN)]BPh4 confirmed the P,P,N chelation mode of the ligand. In solution, this complex displayed hemilabile behaviour, with the pyridyl nitrogens exchanging at a rate faster than the NMR time scale at room temperature.

  18. 2-Methylpyridinium/pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olates as potent anticonvulsant agents—synthesis and crystal structure

    SciTech Connect

    Mangaiyarkarasi, G.; Kalaivani, D.

    2013-12-15

    The molecular salt, 2-methylpyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropy-rimidin-4-olate) (I), is prepared from the ethanolic solution of 1-chloro-2,4-dinitrobenzene, pyrimidine-2,4,6-(1H,3H,5H)-trione (barbituric acid) and 2-methylpyridine at room temperature, and the molecular salt, pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate (II), is prepared from the same reactants, by dissolving them in hot DMSO and ethanol mixture at 70°C. The structures of I and II are characterized by visible, IR, {sup 1}H-NMR, {sup 13}C-NMR and elemental analysis and confirmed by single crystal X-ray analysis. Both the salts crystallize in triclinic crystal system with sp. gr. P-bar1. They possess noticeable anticonvulsant activity even at low concentration (25 mg/kg). Acute toxicity studies of these complexes indicate that LD{sub 50} values are greater than 1500 mg/kg and the tested animals do not show any behavioural changes.

  19. 2-Methylpyridinium/pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olates as potent anticonvulsant agents—synthesis and crystal structure

    NASA Astrophysics Data System (ADS)

    Mangaiyarkarasi, G.; Kalaivani, D.

    2013-12-01

    The molecular salt, 2-methylpyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropy-rimidin-4-olate) ( I), is prepared from the ethanolic solution of 1-chloro-2,4-dinitrobenzene, pyrimidine-2,4,6-(1H,3H,5H)-trione (barbituric acid) and 2-methylpyridine at room temperature, and the molecular salt, pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate ( II), is prepared from the same reactants, by dissolving them in hot DMSO and ethanol mixture at 70°C. The structures of I and II are characterized by visible, IR, 1H-NMR, 13C-NMR and elemental analysis and confirmed by single crystal X-ray analysis. Both the salts crystallize in triclinic crystal system with sp. gr. . They possess noticeable anticonvulsant activity even at low concentration (25 mg/kg). Acute toxicity studies of these complexes indicate that LD50 values are greater than 1500 mg/kg and the tested animals do not show any behavioural changes.

  20. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  1. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  2. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  3. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  4. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  5. Renoprotection: focus on TRPV1, TRPV4, TRPC6 and TRPM2.

    PubMed

    Markó, L; Mannaa, M; Haschler, T N; Krämer, S; Gollasch, M

    2017-03-01

    Members of the transient receptor potential (TRP) cation channel receptor family have unique sites of regulatory function in the kidney which enables them to promote regional vasodilatation and controlled Ca(2+) influx into podocytes and tubular cells. Activated TRP vanilloid 1 receptor channels (TRPV1) have been found to elicit renoprotection in rodent models of acute kidney injury following ischaemia/reperfusion. Transient receptor potential cation channel, subfamily C, member 6 (TRPC6) in podocytes is involved in chronic proteinuric kidney disease, particularly in focal segmental glomerulosclerosis (FSGS). TRP vanilloid 4 receptor channels (TRPV4) are highly expressed in the kidney, where they induce Ca(2+) influx into endothelial and tubular cells. TRP melastatin (TRPM2) non-selective cation channels are expressed in the cytoplasm and intracellular organelles, where their inhibition ameliorates ischaemic renal pathology. Although some of their basic properties have been recently identified, the renovascular role of TRPV1, TRPV4, TRPC6 and TRPM2 channels in disease states such as obesity, hypertension and diabetes is largely unknown. In this review, we discuss recent evidence for TRPV1, TRPV4, TRPC6 and TRPM2 serving as potential targets for acute and chronic renoprotection in chronic vascular and metabolic disease.

  6. Biotransformation of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-Hexaazaisowurtzitane (CL-20) by Denitrifying Pseudomonas sp. Strain FA1

    DTIC Science & Technology

    2003-09-01

    CoCl26H2O, 0.15 g of ZnCl2, 0.01 g of CuSO4 5H2O, 0.10 g of FeSO47H2O, 0.05 g of Na2MoO4, 0.05 g of NiCl26H2O, and 0.05 g of Na2WO4 2H2O . A...solution was used as the trace element solution and was composed of (per liter of deionized water) 0.20 g of MnSO4H2O, 0.10 g of CaCl2 2H2O , 0.10 g of

  7. Conformational Changes in Inositol 1,3,4,5,6-Pentakisphosphate 2-Kinase upon Substrate Binding

    PubMed Central

    Baños-Sanz, José Ignacio; Sanz-Aparicio, Julia; Whitfield, Hayley; Hamilton, Chris; Brearley, Charles A.; González, Beatriz

    2012-01-01

    Inositol 1,3,4,5,6-pentakisphosphate 2-kinase (IP5 2-K) catalyzes the synthesis of inositol 1,2,3,4,5,6-hexakisphosphate from ATP and IP5. Inositol 1,2,3,4,5,6-hexakisphosphate is implicated in crucial processes such as mRNA export, DNA editing, and phosphorus storage in plants. We previously solved the first structure of an IP5 2-K, which shed light on aspects of substrate recognition. However, failure of IP5 2-K to crystallize in the absence of inositide prompted us to study putative conformational changes upon substrate binding. We have made mutations to residues on a region of the protein that produces a clasp over the active site. A W129A mutant allowed us to capture IP5 2-K in its different conformations by crystallography. Thus, the IP5 2-K apo-form structure displays an open conformation, whereas the nucleotide-bound form shows a half-closed conformation, in contrast to the inositide-bound form obtained previously in a closed conformation. Both nucleotide and inositide binding produce large conformational changes that can be understood as two rigid domain movements, although local changes were also observed. Changes in intrinsic fluorescence upon nucleotide and inositide binding are in agreement with the crystallographic findings. Our work suggests that the clasp might be involved in enzyme kinetics, with the N-terminal lobe being essential for inositide binding and subsequent conformational changes. We also show how IP5 2-K discriminates between inositol 1,3,4,5-tetrakisphosphate and 3,4,5,6-tetrakisphosphate enantiomers and that substrate preference can be manipulated by Arg130 mutation. Altogether, these results provide a framework for rational design of specific inhibitors with potential applications as biological tools for in vivo studies, which could assist in the identification of novel roles for IP5 2-K in mammals. PMID:22745128

  8. Spin dynamics of the organic linear chain compounds (TMTTF)2X (X=SbF6, AsF6, BF4, ReO4, and SCN)

    NASA Astrophysics Data System (ADS)

    Salameh, B.; Yasin, S.; Dumm, M.; Untereiner, G.; Montgomery, L.; Dressel, M.

    2011-05-01

    We have performed a comprehensive investigation on the spin susceptibility of the organic quantum-spin systems (TMTTF)2X (X=SbF6, AsF6, BF4, ReO4, and SCN) in the temperature range from T=1.8 up to 380 K. At elevated temperatures, the spin susceptibility at constant volume (χs)V can be described by a spin-(1)/(2) antiferromagnetic Heisenberg chain with exchange constants J between 400 and 460 K. Below T≈100 K, slight deviations from the model occur due to interchain interaction. At low temperatures, the compounds undergo transitions to various ordered states of structural or magnetic origin that are discussed in detail. The spin-dimerized ground states of (TMTTF)2AsF6 and (TMTTF)2BF4 can be described by an alternating spin chain with a singlet-triplet energy gap Δσ(0)=34.8 and 52 K, respectively. In (TMTTF)2ReO4, however, the spin susceptibility in the anion-ordered state deviates from this model and obeys an activated law with Δσ=1100 K. In the antiferromagnetic ground states of (TMTTF)2SbF6 and (TMTTF)2SCN an increase of the spin susceptibility is observed at the lowest temperatures.

  9. Water Quality Criteria for 2,4-Dinitrotoluene and 2,6-Dinitrotoluene.

    DTIC Science & Technology

    1987-08-01

    TEA ) interfaced to a gas chromatograph is capable of detecting 5 pg of 2,4- DNT in standard solutions. The use of this technique, as well as the...combination of a TEA with HPLC, is suggested for detection of 2,4-DNT in ,, -14- V.J . ". .- "-v - ".7.- < - .’.-- .-.-.p " explosives, explosion debris...hand swabs, and human plasma. Phillips et al. (1983) reported detection limits of 0.05 mg/L [(50 parts per billion (ppb)] using GC/ TEA to determine

  10. μ-2,2',6,6'-Tetramethyl-4,4'-bipyridine-κ2N1:N1'-bis[(diethylenetriamine-κ3N,N',N'')palladium(II)] tetranitrate.

    PubMed

    Seidel, Rüdiger W; Oppel, Iris M

    2011-06-01

    The title compound, [Pd(2)(C(4)H(13)N(3))(2)(C(14)H(16)N(2))](NO(3))(4), comprises discrete tetracationic dumbbell-type dinuclear complex molecules and noncoordinating nitrate anions. Two Pd(dien)(2+) moieties (dien is diethylenetriamine) are joined by the rigid linear exo-bidentate bridging 2,2',6,6'-tetramethyl-4,4'-bipyridine ligand to form the dinuclear complex, which lies across a centre of inversion in the space group P2(1)/n, so that the rings in the 2,2',6,6'-tetramethyl-4,4'-bipyridine bridging ligand are parallel. In the crystal, the primary and secondary amino groups of the dien ligand act as hydrogen-bond donors towards the nitrate anions to form a three-dimensional hydrogen-bond network.

  11. 75 FR 11740 - S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1-cyclohex-2-enyl)-3-methyl-penta-(2Z,4E...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... AGENCY 40 CFR Part 180 S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1- cyclohex-2-enyl)-3-methyl-penta-(2Z,4E)-dienoic Acid; Amendment to an Exemption from the Requirement of a Tolerance AGENCY... exemption from the requirement of a tolerance for residues of the biochemical pesticide S-Abscisic Acid,...

  12. Nominal vs Local Shot-Peening Effects on Fatigue Lifetime in Ti-6Al-2Sn-4Zr-6Mo at Elevated Temperature

    DTIC Science & Technology

    2009-11-01

    PROCEDURE A. Material The materia l in this study was tbe IX + /1 titanium aUoy. Ti- 6 -2- 4 - 6 . in the duplex microstructural condition. Two y,;riants of the...ress level and temperature in the turbine engine alloy Ti-6AI-2Sn-4Zr- 6Mo (Ti- 6 -2- 4 - 6 ). The experimental conditions were chosen to target a regime...defects. which are produced during SP by thermally activated pro- cesses.II~.~1J A detailed discussion of these relaxation elTects in Ti- 6 -2- 4 - 6 is

  13. Nominal Versus Local Shot-Peening Effects on Fatigue Lifetime in Ti-6Al-2Sn-4Zr-6Mo at Elevated Temperature (Preprint)

    DTIC Science & Technology

    2008-09-01

    this study was the α+β titanium alloy, Ti- 6 -2- 4 - 6 , in the duplex microstructural condition. Two variants of the microstructure, which differed...condition, at a given stress level and temperature in the turbine engine alloy, Ti-6Al-2Sn-4Zr-6Mo (Ti- 6 -2- 4 - 6 ). The experimental conditions were chosen to...LSG surface. Fig. 1: Microstructures of the Ti- 6 -2- 4 - 6 alloy considered in the study; (a) Microstructure A and (b) Microstructure

  14. Process for manufacturing bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene

    DOEpatents

    Rasmussen, Paul George; Lawton, Richard Graham

    2014-06-03

    A process to manufacture substituted tetracyano-hexaazatricyclics with the substitutions occurring at the 9 and 10 hydrogens. The process begins with 2,3-dichloro-5,6-dicyanopyrazine, which is reacted to form the desired tetracyano-hexaazatricyclic. Different process embodiments enable different reaction paths to the desired tetracyano-hexaazatricyclic. Different tetracyano-hexaazatricyclic embodiments include bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene and bis(2-methoxyethoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracen- e.

  15. Curing of epoxy resins with 1-DI(2-chloroethoxyphosphinyl) methyl-2,4 and -2,6-diaminobenzene

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, J. A.; Kourtides, D. A.

    1983-01-01

    Fire resistant compositions were prepared using 1-di(2-chloroethoxy-phosphinyl)methyl-2,4- and -2,6-diaminobenzene (DCEPD) as a curing agent for typical epoxy resins such as EPON 828 (Shell), XD 7342 (Dow), and My 720 (Ciba Geigy). In addition, compositions of these three epoxy resins with common curing agents such as m-phenylenediamine (MPD) or 4,4'-diaminodiphenylsulphone (DDS) were studied to compare their reactions with those of DCEPD. The reactivity of the three curing agents toward the epoxy resins, measured by differential calorimetry (DSC), was of the order MPD DCEPD DDS. The relatively lower reactivity of DCEPD toward epoxy resins was attributed to electronic effects.

  16. Proton Relaxation in 1, 3, 5-Triamino-2, 4, 6-Trinitrobenzene (TATB).

    DTIC Science & Technology

    1980-06-16

    AD-AO? 209 NAVAL RESEARCH LAB WASHINGTON DC F/G 7/4 PROTON RELAXATION IN 1. 3, 5-TRIAMINO-2, 4. 6-TRINITROBENZENE C-ETC(Ul~JUN A0 A N GARROWAY , H A...TATB) 1 April - 31 September 1979 S. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(a) S. CONTRACT OR GRANT NUMBER(@) A.N. Garroway and H.A. Resing DE-AP-03

  17. SAGE ANALYSIS OF TRANSCRIPTOME RESPONSES IN ARABIDOPSIS ROOTS EXPOSED TO 2,4,6-TRINITROTOLUENE

    EPA Science Inventory

    Serial Analysis of Gene Expression (SAGE) was used to profile transcript levels in Arabidopsis thaliana roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and ea...

  18. SOIL REDUCES 2,4,6-TRINITROTOLUENE BIOAVAILABILITY AND GENOTOXICITY IN VIVO

    EPA Science Inventory

    Soil Reduces 2,4,6- Trinitrotoluene Bioavailability and Genotoxicity In Vivo

    As chemicals age in soil, irreversible binding of chemical contaminants to organic components in the soil may occur, impacting the amount of chemical that is biologically available upon exp...

  19. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false 4-Hydroxymethyl-2,6-di-tert-butylphenol. 178.2550 Section 178.2550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Antioxidants and...

  20. Preparation of 1,3,5-triamo-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-05-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  1. TOXICITY OF TETRYL (N-METHYL-N,2,4,6-TETRANITROANILINE) IN F344 RATS

    EPA Science Inventory

    The toxicity of tetryl (N-methyl-N,2,4,6-tetranitroaniline) in male and female F344 rats was evaluated after adminstration in the diet for 14 or 90 days. The 14-day study diet concentrations used were 0, 500, 1250, 2000, 2500, and 5000 ppm; the 90-day study diet concentrations we...

  2. Mineralization of 2,4,6-Trinitrotoleune (TNT) in Coastal Waters and Sediments

    DTIC Science & Technology

    2006-08-21

    sp. and Staphylococcus sp. (Kalafut et al. 1998), actinomycetes (Pasti- Grigsby et al. 1996), Enterobacter cloacae (French et al. 1998), Klebsiella sp...Pasti-Grigsby, MB, Lewis, TA, Crawford, DL, Crawford, RL (1996). Transformation of 2,4,6- Trinitrotoluene (TNT) by Actinomycetes isolated from TNT

  3. Preparation of 3,3'-azobis(6-amino-1,2,4,5-tetrazine)

    DOEpatents

    Hiskey, Michael A.; Chavez, David E.; Naud, Darren

    2002-01-01

    The compound of the structure ##STR1## where a, b, c, d and e are 0 or 1 and a+b+c+d+e is from 0 to 5 is disclosed together with the species 3,3'-azobis(6-amino-1,2,4,5-tetrazine) and a process of preparing such compounds.

  4. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-01-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  5. [Screening of new 2,4- and 2,6-dinitroaniline derivates for phytotoxicity and antimitotic activity].

    PubMed

    Ozheredov, S P; Emets, A I; Brytsun, V N; Ozheredova, I P; Lozinskiĭ, M O; Blium, Ia B

    2009-01-01

    The results of Allium-test screening of new 2,4- and 2,6-dinitroaniline derivates on antimitotic activity and phytotoxicity are presented in the work. It is revealed that all studied compounds which are derivates of 2,4-dinitroaniline, 2,6-dinitro-(4-fluoromethyl)-aniline as well as (methylsulfonyl) nitrobenzol, can evoke a change in mitotic index value, an appearance of cytogenetic damages and also have phytotoxic effect on Allium cepa seedling roots. On data obtained the continuation of investigation the action of N-(2,4-dinitrophenyl)-orto-aminobenzoic acid, N,N-diethyl-2,6-dinitro-4-(trifluoromethyl)-aniline and 1-methylsulfonyl-3-nitrobenzol as potential herbicides is proposed.

  6. Ca2+ sensitization in idiopathic dilated human myocardium. Differential in vitro effects of (+)-(5-methyl-6-phenyl)-1,3,5,6-tetrahydro-3,6-methano-1,5-benzodiazoci ne-2,4-dione, a novel purely Ca2+sensitizing agent, and (+)-5-(1-(3,4-dimethoxybenzoyl)-1,2,3,4-tetrahydroquinolin-6-yl)-6-meth yl-3, 6-dihydro-2H-1,3,4-thiadiazin-2-one on skinned fibres and isolated ventricular strips.

    PubMed

    Herzig, J W; Chiesi, M; Depersin, H; Grüninger, S; Hasenfuss, G; Kubalek, R; Leutert, T; Pieske, B; Pioch, K; Wenk, P; Holubarsch, C

    1996-06-01

    (+)-(5-Methyl-6-phenyl)-1,3,5,6-tetrahydro-3,6-methano-1, 5-benzodiazocine-2,4-dione (CAS 165755-40-8, CGP 48506) is a novel Ca2+ sensitizing agent devoid of any other positive inotropic mechanism, particularly phosphodiesterase (PDE) III inhibition. 5-(1-(3,4-Dimethoxybenzoyl)-1,2,3,4-tetrahydroquinolin-6-yl)-6-met hyl-3, 6-dihydro-2H-1,3,4-thiadiazin-2-one (CAS 120223-04-3, EMD 53998) is a PDE III inhibitor with a Ca2+ sensitizing activity residing in its (+)-enantiomer, EMD 57033 (CAS 147527-31-9). In skinned fibres and electrically stimulated left ventricular strips from idiopathic dilated human hearts, New York Heart Association (NYHA) class IV, the Ca2+ sensitizing and inotropic effects of the benzodiazocine CGP 48506 and the thiadiazinones EMD 53998 or EMD 57033 were compared. Both CGP 48506 and EMD 53998 induce a left shift of the Ca2+ activation curve of force towards lower Ca2+ concentrations in skinned fibres, which indicates Ca2+ sensitization. Only EMD 53998, but not CGP 48506, increases skinned fibre force at both minimum (resting) and maximally activating Ca2+ concentrations. This is taken as an argument for a principal difference in the mechanisms of the Ca2+ sensitizing actions of the two compounds. CGP 48506 is shown not to influence the amplitude of the Ca2+ transient in rat cardiomyocytes. On the other hand, both CGP 48506 and EMD 57033 show comparable, though quantitatively different, positive inotropic effects in electrically stimulated left ventricular strip preparations. It is unclear whether the PDE III inhibitory component of the profile of actions of EMD 57033 may play a role in preventing the increase in diastolic tension as expected from the skinned fibre experiments. It is noteworthy that both Ca2+ sensitizing agents act as positive inotropic compounds in the end-stage failing human heart where other inotropic agents like beta 1-adrenergic agonists or PDE inhibitors have been described to fail.

  7. Variation of Physical Properties in the Nominal Sr4V2O6Fe2As2

    SciTech Connect

    Sefat, A. S.; Garlea, Vasile O; Singh, David J; McGuire, Michael A; Sales, Brian C; Zuev, Yuri L

    2011-01-01

    We show using a combination of powder X-ray and neutron diffraction, first principles calculations, temperature- and field-dependent magnetization, heat capacity and resistivity data that the superconducting behavior of Sr4V2O6Fe2As2 is dependent on synthesis conditions, particularly, heating profiles result in unintentional chemical doping. This compound can be tuned from a state in which the vanadium electrons are itinerant with a high electronic density of states, to a state where the vanadium-oxide layers are insulating and presumably magnetic.

  8. Variation of Physical Properties in the Nominal Sr4V2O6Fe2As2

    SciTech Connect

    Safa-Sefat, Athena; Singh, David J; Garlea, Vasile O; Zuev, Yuri L; McGuire, Michael A; Sales, Brian C

    2011-01-01

    We show using a combination of powder X-ray and neutron diffraction, first-principles calculations, temperature- and field-dependent magnetization, heat capacity and resistivity data that the superconducting behavior of Sr{sub 4}V{sub 2}O{sub 6}Fe{sub 2}As{sub 2} is dependent on synthesis conditions, particularly, heating profiles result in unintentional chemical doping. This compound can be tuned from a state in which the vanadium electrons are itinerant with a high electronic density of states, to a state where the vanadium-oxide layers are insulating and presumably magnetic.

  9. Ferroelectric properties and polarization dynamics in Ba4Sm2Ti4Ta6O30 tungsten bronze ceramics

    NASA Astrophysics Data System (ADS)

    Zhu, Xiao Li; Chen, Xiang Ming

    2016-04-01

    Ferroelectricity and polarization reversal dynamics in Ba4Sm2Ti4Ta6O30 tungsten bronze ceramics were investigated by measuring dielectric spectra and the evolution of hysteresis loops over a wide temperature range. With decreasing temperature, the dielectric properties and differential scanning calorimetry results showed diffuse peaks at ˜280 K with large thermal hysteresis, suggesting a first order ferroelectric transition. A dielectric relaxation was observed at low temperature that followed the Vogel-Fulcher relationship. The saturation and remanent polarizations of the Ba4Sm2Ti4Ta6O30 ceramics showed remarkable dependence on the applied field and temperature. The temperature dependence of the coercive field was divided into three linear regions and fitted to the Vopsaroiu model. Activation energies for polarization reversal of 0.73, 0.79, and 0.65 eV were determined for the following three regions: (I) the diffuse ferroelectric transition region (323.15-293.15 K), (II) the region just below the ferroelectric transition temperature (293.15-233.15 K), and (III) the low temperature relaxation region (233.15-173.15 K), respectively. The decrease of the activation energy in region III was attributed to the low temperature relaxation of Ba4Sm2Ti4Ta6O30.

  10. 2-Amino-6-methyl­pyridinium 4-methyl­benzene­sulfonate

    PubMed Central

    Babu, K. Syed Suresh; Dhavamurthy, M.; NizamMohideen, M.; Peramaiyan, G.; Mohan, R.

    2014-01-01

    In the asymmetric unit of the title salt, C6H9N2 +·C7H7O3S−, there are two independent 2-amino-6-methyl­pyridinium cations and two independent 4-methyl­benzene­sulfonate anions. Both cations are protonated at their pyridine N atoms and their geometries reveal amine–imine tautomerism. In the 4-methyl­benzene­sulfonate anions, the carboxyl­ate groups are twisted out of the benzene ring planes by 88.4 (1) and 86.2 (2)°. In the crystal, the sulfonate O atoms of an anion inter­act with the protonated N atoms and the 2-amino groups of a cation via a pair of N—H⋯O hydrogen bonds, forming an R 2 2(8) ring motif. These motifs are connected via N—H⋯O hydrogen bonds, forming chains running along the a-axis direction. Within the chains there are weak C—H⋯O hydrogen bonds present. In addition, aromatic π–π stacking inter­actions [centroid–centroid distances = 3.771 (2), 3.599 (2), 3.599 (2) and 3.497 (2) Å] involving neighbouring chains are also observed. PMID:24860395

  11. Brr2 plays a role in spliceosomal activation in addition to U4/U6 unwinding.

    PubMed

    Zhang, Lingdi; Li, Xueni; Hill, Ryan C; Qiu, Yan; Zhang, Wenzheng; Hansen, Kirk C; Zhao, Rui

    2015-03-31

    Brr2 is a DExD/H-box RNA helicase that is responsible for U4/U6 unwinding, a critical step in spliceosomal activation. Brr2 is a large protein (∼250 kD) that consists of an N-terminal domain (∼500 residues) with unknown function and two Hel308-like modules that are responsible for RNA unwinding. Here we demonstrate that removal of the entire N-terminal domain is lethal to Saccharomyces cerevisiae and deletion of the N-terminal 120 residues leads to splicing defects and severely impaired growth. This N-terminal truncation does not significantly affect Brr2's helicase activity. Brr2-Δ120 can be successfully assembled into the tri-snRNP (albeit at a lower level than the WT Brr2) and the spliceosomal B complex. However, the truncation significantly impairs spliceosomal activation, leading to a dramatic reduction of U5, U6 snRNAs and accumulation of U1 snRNA in the B(act) complex. The N-terminal domain of Brr2 does not seem to be directly involved in regulating U1/5'ss unwinding. Instead, the N-terminal domain seems to be critical for retaining U5 and U6 snRNPs during/after spliceosomal activation through its interaction with snRNAs and possibly other spliceosomal proteins, revealing a new role of Brr2 in spliceosomal activation in addition to U4/U6 unwinding.

  12. Natural product-based 6-hydroxy-2 3 4 6-tetrahydropyrrolo[1 2-a]pyrimidinium Scaffold as a new antifungal template

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic analogues of the marine-derived class of natural products phloeodictines have been prepared and exhibited potent in vitro fungicidal activities against a broad array of fungal pathogens including drug-resistant strains. The 6-hydroxy-2,3,4,6-tetrahydropyrrolo[1,2-a] pyrimidinium structura...

  13. Construction of a Pseudomonas hybrid strain that mineralizes 2,4,6-trinitrotoluene.

    PubMed Central

    Duque, E; Haidour, A; Godoy, F; Ramos, J L

    1993-01-01

    A bacterium, Pseudomonas sp. strain C1S1, able to grow on 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as N sources, was isolated. The bacterium grew at 30 degrees C with fructose as a C source and accumulated nitrite. Through batch culture enrichment, we isolated a derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium. Use of TNT by these two strains as an N source involved the successive removal of nitro groups to yield 2,4- and 2,6-dinitrotoluene, 2-nitrotoluene, and toluene. Transfer of the Pseudomonas putida TOL plasmid pWW0-Km to Pseudomonas sp. clone A allowed the transconjugant bacteria to grow on TNT as the sole C and N source. All bacteria in this study, in addition to removing nitro groups from TNT, reduced nitro groups on the aromatic ring via hydroxylamine to amino derivatives. Azoxy dimers probably resulting from the condensation of partially reduced TNT derivatives were also found. PMID:8468288

  14. Volumetric Properties of the Mixture (+,-)-Methyl-1,3-dioxolan-2-one C4H6O3 + C6H12O3 2,4,6-Trimethyl-1,3,5-trioxane (VMSD1511, LB4523_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture (+,-)-Methyl-1,3-dioxolan-2-one C4H6O3 + C6H12O3 2,4,6-Trimethyl-1,3,5-trioxane (VMSD1511, LB4523_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  15. Conjugated microporous polymers-based fluorescein for fluorescence detection of 2,4,6-trinitrophenol.

    PubMed

    Geng, Tong-Mou; Ye, Sai-Nan; Wang, Yu; Zhu, Hai; Wang, Xie; Liu, Xue

    2017-04-01

    2,4,6-Trinitrophenol (TNP, also called picric acid, PA) pose a large threat to environmental health, public safety and military security. Conjugated microporous polymers are emerging new fluorescence sensing materials for TNP. In this paper, we report the synthesis of two fluorescein containing conjugated microporous polymers (DTF and TTF) through the palladium catalyzed Sonogashira-Hagihara polycondensation reactions of tetraiodofluorescein sodium salt (TIFA) with 1,4-diethynylbenzene (DEB) or 1,3,5-triethynylbenzene (TEB). DTF and TTF are porous with the BET surface areas of 705 and 712m(2)g(-1) and exhibit high chemical and thermal stabilities. The formation of conjugated polymers with the incorporation of ethynyl groups leads to the fluorescent properties. The fluorescence quenching behaviors of DTF by nitroaromatic analytes in THF suspension are investigated. It is found that the fluorescence of DTF can be effectively quenched by 2,4,6-trinitrophenol over 2-nitrophenol (NP), 4-nitrotoluene (NT), nitrobenzene (NB), phenol (PhOH), p-dichlorobenzene (DClB) and 2,4-dinitrotoluene (DNT) with an SV constant of 2.08×10(3)Lmol(-1) and a detection limit of 7.22×10(-7)molL(-1) (0.165mgL(-1)). In short, the DTF may be a new kind of fluorescence sensing material for detecting TNP.

  16. Observations of CH4, C2H6, and C2H2 in the stratosphere of Jupiter.

    PubMed

    Sada, P V; Bjoraker, G L; Jennings, D E; McCabe, G H; Romani, P N

    1998-12-01

    We have performed high-resolution spectral observations at mid-infrared wavelengths of CH4 (8.14 micrometers), C2H6 (12.16 micrometers), and C2H2 (13.45 micrometers) on Jupiter. These emission features probe the stratosphere of the planet and provide information on the carbon-based photochemical processes taking place in that region of the atmosphere. The observations were performed using our cryogenic echelle spectrometer CELESTE, in conjunction with the McMath-Pierce 1.5-m solar telescope between November 1994 and February 1995. We used the methane observations to derive the temperature profile of the jovian atmosphere in the 1-10 mbar region of the stratosphere. This profile was then used in conjunction with height-dependent mixing ratios of each hydrocarbon to determine global abundances for ethane and acetylene. The resulting mixing ratios are 3.9(+1.9)(-1.3) x 10(-6) for C2H6 (5 mbar pressure level), and 2.3 +/- 0.5 x 10(-8) for C2H2 (8 mbar pressure level), where the quoted uncertainties are derived from model variations in the temperature profile which match the methane observation uncertainties.

  17. Protonation of calix[4]arene-(2,3-naphthylene-crown-6,crown-6): Experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Kvíčalová, Magdalena; Makrlík, Emanuel; Böhm, Stanislav; Vaňura, Petr; Asfari, Zouhair

    2017-04-01

    On the basis of extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium H3O+ (aq) + 1·Na+ (nb) ⇄1·H3O+ (nb) + Na+ (aq) occurring in the two-phase water-nitrobenzene system (1 = calix[4]arene-(2,3-naphthylene-crown-6,crown-6); aq = aqueous phase, nb = nitrobenzene phase) was determined as log Kex(H3O+,1·Na+) = -0.2 ± 0.1. Further, the stability constant of the 1·H3O+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log βnb(1·H3O+) = 5.9 ± 0.2. Finally, applying quantum chemical DFT calculations, the most probable structure of the cationic complex species 1·H3O+ was derived. In the resulting complex, the "central" cation H3O+ is bound by three strong hydrogen bonds to two phenoxy oxygen atoms and to one ethereal oxygen from the crown-6 moiety of the parent ligand 1. The interaction energy, E(int), of the considered 1·H3O+ complex was found to be -416.0 kJ/mol, confirming the formation of this cationic species as well.

  18. Chiral 6-aryl-furo[2,3-d]pyrimidin-4-amines as EGFR inhibitors.

    PubMed

    Han, Jin; Kaspersen, Svein Jacob; Nervik, Sondre; Nørsett, Kristin G; Sundby, Eirik; Hoff, Bård Helge

    2016-08-25

    Epidermal growth factor receptor inhibitors are of importance in cancer therapy and possibly in the management of pain. Herein, we report a structure-activity relationship study with 29 new 6-aryl-furo[2,3-d]pyrimidin-4-amines, involving modification of the 4-amino group and 6-aryl function. The EGFR activity was especially dependent on having a chiral 4-benzylamino group with correct stereochemistry. Molecular dynamics indicate this to be due to favourable cation-π interactions. The most active inhibitor identified, equipotent to Erlotinib, was substituted with (R)-1-phenylethylamine at C-4 and a N(1), N(1)-dimethyl-1,2-diamine group in para position of the 6-aryl moiety. These new furopyrimidines had a different off-target kinase profile when compared to Erlotinib, and also possessed high activity towards Ba/F3 EGFR(L858R) reporter cells. Further, comparing the EGFR data of the furo[2,3-d]pyrimidin-4-amines with that of the corresponding thieno- and pyrrolopyrimidines concludes the furopyrimidine scaffold to be highly useful for development of new epidermal growth factor receptor antagonists.

  19. Synthesis, stereochemical, structural and biological studies of some 2,6-diarylpiperidin-4-one N(4‧)-cyclohexyl thiosemicarbazones

    NASA Astrophysics Data System (ADS)

    Sethukumar, A.; Udhaya Kumar, C.; Agilandeshwari, R.; Arul Prakasam, B.

    2013-09-01

    A new series of 2,6-diarylpiperidin-4-one N(4')-cyclohexyl thiosemicarbazones (13-23) were synthesized by corresponding 2,6-diarylpiperidin-4-ones (1-11) reaction with cyclohexyl thiosemicarbazide (12). The chemical structures were confirmed by means of IR, one and two dimensional NMR, Mass spectra and single crystal X-ray diffraction analysis. Compounds 13-23, exist in chair conformation with equatorial orientation of all the substituents at piperidine ring except the methyl group at C-5 of compounds 21-23 oriented at axial disposition to stabilize the chair conformation. Single crystal X-ray structural analysis of compound 18, evidences that the configuration about Cdbnd N double bond is syn to C-5 carbon (E-form). All the synthesized compounds were screened their biological activity.

  20. Polymer of phosphonylmethyl-2,4- and -2,6-diamino benzene and polyfunctional monomer

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, J. A. (Inventor); Kourtides, D. A. (Inventor)

    1986-01-01

    A phosphonyl methyl benzene is prepared by nitration to produce a 2,4-dinitro phosphonyl methyl benzene, which is then reduced to a diamino compound. The diamino compound is then used to cure a polymerizable monomer. The diamino compound may be polymerized with polyfunctional epoxides to produce heat and fire resistant polymer structures for making flame and fire resistant polymer structures such as for aircraft secondary structures.

  1. 6-Hydroxy-methyl-4-meth-oxy-2H-pyran-2-one (Opuntiol).

    PubMed

    Abbasi, Muhammad Athar; Shahzadi, Tayyaba; Akkurt, Mehmet; Aziz-Ur-Rehman; Riaz, Tauheeda

    2009-12-19

    The title compound, C(7)H(8)O(4), isolated from Opuntia dillenii Haw (Cacta-ceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C-H⋯O and O-H⋯O inter-molecular hydrogen bonds, resulting in the formation of a three-dimensional network.

  2. Synthesis and properties of fluorescent 4′-azulenyl-functionalized 2,2′:6′,2″-terpyridines

    PubMed Central

    Ion, Adrian E; Cristian, Liliana; Voicescu, Mariana; Bangesh, Masroor; Madalan, Augustin M; Bala, Daniela; Mihailciuc, Constantin

    2016-01-01

    Summary 4′-Azulenyl-substituted terpyridines were efficiently synthesized following the Kröhnke methodology via azulenylchalcone intermediates. These azulenyl-containing terpyridines showed fluorescent emission with a fluorescence quantum yield varying from 0.14, in the case of parent terpyridine, to 0.64 when methyl groups are grafted on the azulenyl seven-membered ring. According to the crystal structures and TDDFT calculations, different twisting of the aromatic constituents is responsible for the observed fluorescent behavior. The electrochemical profile contains one-electron oxidation/reduction steps, which can only be explained on the basis of the redox behavior of the azulene unit. The ability of the 4′-azulenyl 2,2′:6′,2″-terpyridine to bind poisoning metal cations was studied by UV–vis titrations using aqueous solutions of Hg(II) and Cd(II) chlorides as illustrative examples. PMID:27829888

  3. Structural and computational characterization of 4‧,4‧,6‧,6‧-tetrachloro-3-(2-methoxyethyl)-3H,4H-spiro-1,3,2-benzoxaza phosphinine-2,2‧- [1,3,5,2,4,6] triazatriphosphinine

    NASA Astrophysics Data System (ADS)

    Işıklan, Muhammet; Yıldırım, Erdem Kamil; Atiş, Murat; Sonkaya, Ömer; Çoşut, Bünyemin

    2016-08-01

    In this study a new monospirocyclic phosphazene derivative, 4‧,4‧,6‧,6‧-tetrachloro-3-(2-methoxyethyl)-3H,4H-spiro [1,3,2-benzoxazaphosphinine-2,2‧- [1,3,5,2,4,6] triazatriphosphinine] (SP1) was synthesized from the reaction of hexachlorocyclotriphosphazene (N3P3Cl6) with N/O donor-type, 2-{[(2-Metoxyethyl) amino]methyl}phenol. The structural investigations of the compound were verified by elemental analyses, MS, FTIR, 1H, 13C, 31P NMR spectroscopy and the single crystal X-ray diffraction analysis. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method (DFT) using 6-311++G (d, p) basis set. The complete assignments of all vibrational modes were performed on the basis of the total energy distributions (TED). Isotropic chemical shifts (31P, 1H and 13C NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. Theoretical calculations of bond parameters, harmonic vibration frequencies and nuclear magnetic resonance are in good agreement with experimental results. The electrophilic and nucleophilic attack centers in SP1 were predicted with the local softness values (sk+, and sk-) of individual atoms and it is confirmed that P atoms of the PCl2 groups are nucleophilic attack centers.

  4. Synthesis of biologically active 1'-(2-oxo-2H-benzopyran-6-yl)- 5'-hydroxy-2'-methylindole-3'-amido-2"-phenyl-thiazolidene-4"-ones.

    PubMed

    Mulwad, Vinata V; Parmar, Hitesh T; Mir, Abid A

    2011-01-01

    6-Aminocoumarins on refluxing with ethyl acetoacetate in 1,2-dichloroethane gave two products: 3'-(2-oxo-2H-benzopyran-6-yl-amino)-but-2'-enoic acid ethyl ester 2a-c and N-(-2-oxo-2H-benzopyran-6-yl)-3'-oxo-butyramide 3a-c. Compounds 2a-c on treatment with 1,4-benzoquinone in N2-atmosphere yielded 1'-( 2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methyl-3'-carbethoxyindoles 4a-c, which on further treatment with hydrazine hydrate gave 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-acid hydrazides 5a-c. These acid hydrazides were treated with benzaldehyde to give 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-benzylidene hydrazides 6a-c, which on further treatment with mercaptoacetic acid in 1,4-dioxane yielded 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-amido-2"-phenylthiazolidene-4"-ones 7a-c. The structures of the compounds have been established on the basis of spectral and analytical data. All compounds have been screened for their antimicrobial activity and have been found to exhibit significant antibacterial and antifungal activities.

  5. Identification of urinary metabolites of 2,4,6-trinitrotoluene in rats by liquid chromatography-mass spectometry.

    PubMed

    Yinon, J; Hwang, D G

    1985-08-01

    Metabolites of 2,4,6-trinitrotoluene (TNT) were found in the urine of rats fed with TNT. The urine extracts were analysed by liquid chromatography-mass spectrometry (LC-MS). Metabolites found included TNT itself as well as 2-amino-4,6-dinitrotoluene, 4-amino-2,6-dinitrotoluene and 2,4-diamino-6-nitrotoluene, indicating that reduction processes are responsible for the formation of these metabolites.

  6. Broadband Yellowish-Green Emitting Ba4Gd3Na3(PO4)6F2:Eu(2+) Phosphor: Structure Refinement, Energy Transfer, and Thermal Stability.

    PubMed

    Fu, Xiaopeng; Lü, Wei; Jiao, Mengmeng; You, Hongpeng

    2016-06-20

    A series of Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphors with a broad emitting band have been synthesized by a traditional solid state reaction. The crystal structural and photoluminescence properties of Ba4Gd3Na3(PO4)6F2:Eu(2+) are investigated. The different crystallographic sites of Eu(2+) in Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphors have been verified by means of their photoluminescence (PL) properties and decay times. Energy transfer between Eu(2+) ions, analyzed by excitation, emission, and PL decay behavior, has been indicated to be a dipole-dipole mechanism. Moreover, the luminescence quantum yield as well as the thermal stability of the Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphor have been investigated systematically. The as-prepared Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphor can act as a promising candidate for n-UV convertible white LEDs.

  7. Phase Polymorphism of [Co(DMSO)6](BF4)2 Studied by Differential Scanning Calorimetry

    NASA Astrophysics Data System (ADS)

    Migdał-Mikuli, Anna; Skoczylas, Łukasz; Szostak, Elżbieta

    2006-04-01

    Five solid phases of [Co(DMSO)6](BF4)2 have been detected by differential scanning calorimetry (DSC). Phase transitions were detected between the following solid phases: stable KIb↔ stable KIa at T̅C4 = (328±2) K, metastable KIII ↔ undercooled phase K0 at T̅C3 = (383±4) K, metastable KII ↔ undercooled K0 at T̅C2 = (399±2) K and stable KIa ↔ stable K0 at T̅C1 = (404±1) K. The title compound melts at Tm = 440 K. From the entropy changes at the melting point and at phase transitions it can be concluded that the phases K0 and undercooled K0 are orientationally dynamically disordered crystals. The stable phases KIa, KIb are ordered solid phases. The metastable phases KII and KIII are probably solid phases with a high degree of orientational dynamical disorder

  8. Crystal structure of tetra-wickmanite, Mn(2+)Sn(4+)(OH)6.

    PubMed

    Lafuente, Barbara; Yang, Hexiong; Downs, Robert T

    2015-02-01

    The crystal structure of tetra-wickmanite, ideally Mn(2+)Sn(4+)(OH)6 [mangan-ese(II) tin(IV) hexa-hydroxide], has been determined based on single-crystal X-ray diffraction data collected from a natural sample from Långban, Sweden. Tetra-wickmanite belongs to the octa-hedral-framework group of hydroxide-perovskite minerals, described by the general formula BB'(OH)6 with a perovskite derivative structure. The structure differs from that of an ABO3 perovskite in that the A site is empty while each O atom is bonded to an H atom. The perovskite B-type cations split into ordered B and B' sites, which are occupied by Mn(2+) and Sn(4+), respectively. Tetra-wickmanite exhibits tetra-gonal symmetry and is topologically similar to its cubic polymorph, wickmanite. The tetra-wickmanite structure is characterized by a framework of alternating corner-linked [Mn(2+)(OH)6] and [Sn(4+)(OH)6] octa-hedra, both with point-group symmetry -1. Four of the five distinct H atoms in the structure are statistically disordered. The vacant A site is in a cavity in the centre of a distorted cube formed by eight octa-hedra at the corners. However, the hydrogen-atom positions and their hydrogen bonds are not equivalent in every cavity, resulting in two distinct environments. One of the cavities contains a ring of four hydrogen bonds, similar to that found in wickmanite, while the other cavity is more distorted and forms crankshaft-type chains of hydrogen bonds, as previously proposed for tetra-gonal stottite, Fe(2+)Ge(4+)(OH)6.

  9. Crystal structure of tetra­wickmanite, Mn2+Sn4+(OH)6

    PubMed Central

    Lafuente, Barbara; Yang, Hexiong; Downs, Robert T.

    2015-01-01

    The crystal structure of tetra­wickmanite, ideally Mn2+Sn4+(OH)6 [mangan­ese(II) tin(IV) hexa­hydroxide], has been determined based on single-crystal X-ray diffraction data collected from a natural sample from Långban, Sweden. Tetra­wickmanite belongs to the octa­hedral-framework group of hydroxide-perovskite minerals, described by the general formula BB’(OH)6 with a perovskite derivative structure. The structure differs from that of an ABO3 perovskite in that the A site is empty while each O atom is bonded to an H atom. The perovskite B-type cations split into ordered B and B′ sites, which are occupied by Mn2+ and Sn4+, respectively. Tetra­wickmanite exhibits tetra­gonal symmetry and is topologically similar to its cubic polymorph, wickmanite. The tetra­wickmanite structure is characterized by a framework of alternating corner-linked [Mn2+(OH)6] and [Sn4+(OH)6] octa­hedra, both with point-group symmetry -1. Four of the five distinct H atoms in the structure are statistically disordered. The vacant A site is in a cavity in the centre of a distorted cube formed by eight octa­hedra at the corners. However, the hydrogen-atom positions and their hydrogen bonds are not equivalent in every cavity, resulting in two distinct environments. One of the cavities contains a ring of four hydrogen bonds, similar to that found in wickmanite, while the other cavity is more distorted and forms crankshaft-type chains of hydrogen bonds, as previously proposed for tetra­gonal stottite, Fe2+Ge4+(OH)6. PMID:25878828

  10. 2,4,6-Trichloroanisole is a potent suppressor of olfactory signal transduction

    PubMed Central

    Takeuchi, Hiroko; Kato, Hiroyuki; Kurahashi, Takashi

    2013-01-01

    We investigated the sensitivity of single olfactory receptor cells to 2,4,6-trichloroanisole (TCA), a compound known for causing cork taint in wines. Such off-flavors have been thought to originate from unpleasant odor qualities evoked by contaminants. However, we here show that TCA attenuates olfactory transduction by suppressing cyclic nucleotide-gated channels, without evoking odorant responses. Surprisingly, suppression was observed even at extremely low (i.e., attomolar) TCA concentrations. The high sensitivity to TCA was associated with temporal integration of the suppression effect. We confirmed that potent suppression by TCA and similar compounds was correlated with their lipophilicity, as quantified by the partition coefficient at octanol/water boundary (pH 7.4), suggesting that channel suppression is mediated by a partitioning of TCA into the lipid bilayer of plasma membranes. The rank order of suppression matched human recognition of off-flavors: TCA equivalent to 2,4,6-tribromoanisole, which is much greater than 2,4,6-trichlorophenol. Furthermore, TCA was detected in a wide variety of foods and beverages surveyed for odor losses. Our findings demonstrate a potential molecular mechanism for the reduction of flavor. PMID:24043819

  11. Biotransformation of 2,4,6-trinitrotoluene in Anabaena sp. cultures

    SciTech Connect

    Pavlostathis, S.G.; Jackson, G.H.

    1999-03-01

    The transformation of 2,4,6-trinitrotoluene (TNT) was investigated in cultures of the cyanobacterium Anabaena sp. by conducting a series of batch assays. 2,4,6-Trinitrotoluene was added to Anabaena sp. cultures in single and consecutive additions, at various initial concentrations, to determine its transformation kinetics, to identify products formed, to evaluate potential toxicity, and to determine the effect of light deprivation on the TNT transformation process. 2,4,6-Trinitrotoluene disappearance occurred only in the presence of Anabaena sp. cultures maintained under a normal 16-h photoperiod. Toxicity leading to culture chlorosis and death was observed in batch systems with an initial TNT concentration greater than 10 mg/L. A low rate and extent of TNT disappearance was observed in light-deprived cultures, which were inhibited even at low TNT concentrations. At pH values between 7.5 and 8.5, azoxy-tetranitrotoluene isomers were detected in both the culture medium and solvent extracts of biomass and accounted for only 20 and 4.4% of the initially added TNT moles, respectively. At a culture pH range between 5.6 and 5.9, achieved by aeration with a 5% CO{sub 2}/air mixture, hydroxylaminodinitrotoluene equimolar to the TNT addition was produced and then depleted from the culture medium with prolonged incubation. Although TNT reduction in Anabaena sp. cultures occurred, yielding low levels of azoxy-tetranitrotoluene isomers or hydroxylaminodinitrotoluene, uptake and other transformation reactions of TNT and/or its transformation products by Anabaena sp. may have taken place. Based on a less than 15% observed increase of biomass concentration over the relatively short incubation periods and by considering the mean biomass concentration constant, the TNT disappearance rate followed pseudo-first-order kinetics. The biomass carbon-normalized TNT disappearance rates in Anabaena sp. cultures were about three orders of magnitude higher than previously reported TNT

  12. Analysis of 2,4,6-nonatrienal geometrical isomers from male flea beetles, Epitrix hirtipennis and E. fuscula

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2E,4E,6Z) and (2E,4E,6E) isomers as components of its male-produced aggregation pheromone. Here, we l...

  13. Phase Polymorphism of [Mn(DMSO)6](BF4)2 Studied by Differential Scanning Calorimetry

    NASA Astrophysics Data System (ADS)

    Migdał-Mikuli, Anna; Skoczylas, Łukasz

    2008-12-01

    The tetrafluoroborate of hexadimethylsulfoxidemanganese(II) was synthesized and studied by differential scanning calorimetry. Five solid phases of [Mn(DMSO)6](BF4)2 were revealed. Specifically, four phase transitions of the first order were detected between the following solid phases: stable KIb↔stable KIa at TC4 = 215 K; metastable KIII↔overcooled K0 at TC3 = 354 K; metastable KII↔overcooled K0 at TC2 =377 K; stable KIa→stable K0 at TC1 =385 K. [Mn(DMSO)6](BF4)2 starts to decompose at 400 K with a loss of one DMSO molecule per formula unit and forms [Mn(DMSO)5](BF4)2 which next decomposes in one step to MnF2 at the temperature range of 460 - 583 K. From the entropy changes it can be concluded that the phases K0 and metastable KII are orientationally dynamically disordered (ODDIC) crystals. The stable phases KIb and KIa are ordered solid phases.

  14. 2-Methyl-sulfanyl-5,6-dihydro-2H-1,3-dithiolo[4,5-b][1,4]dioxin-2-ium tetra-fluoro-borate.

    PubMed

    Zhou, Guoquan; Chen, Xinzhi

    2012-04-01

    The title compound, C(6)H(7)O(2)S(3) (+)·BF(4) (-), consists of a planar 2-thioxo-1,3-dithiol-4,5-yl unit [maximum deviation from the ring plane = 0.020 (3) Å], with an ethyl-enedi-oxy group fused at the 4,5-positions; the ethyl-enedi-oxy C atoms are disordered over two positions with site-occupancy factors of 0.5. The 1,4-dioxine ring has a twist-chair conformation. Weak cation-anion S⋯F inter-actions [3.022 (4)-3.095 (4) Å] and an S⋯O [3.247 (4) Å] inter-action are present.

  15. Concentrations of organochlorine pesticides and 2,4,6-trichloroanisole in cork bark.

    PubMed

    Olivella, M Àngels; Caixach, Josep; Planas, Carles; Oliveras, Anna; Jové, Patrícia

    2012-02-01

    Organochlorine pesticides are persistent lipophilic organic pollutants and tend to accumulate in growing plants. During growth, cork is in contact with the open air for long periods (9-12 years). Owing to the previous widespread use of organochlorine pesticides and their high persistence in the environment, there is a risk that residues of such pesticides may be present in cork. In this study, the concentrations of 14 organochlorine pesticides-all of which are indicators of environmental pollution-were analyzed in cork bark samples from three regions in Spain and one in Portugal. In addition, the concentrations of 2,4,6-trichlorophenol (TCP) and 2,4,6-trichloroanisole (TCA) were also analyzed. Our results show only very low concentrations of lindane, γ-HCH (<2.6 ng g(-1)) and its byproducts α-HCH (<3.5 ng g(-1)) and β-HCH (<0.6 ng g(-1)). Among the DDT and its metabolites, only two were found: p,p'-DDT was found in a cork sample from Extremadura (0.1 ng g(-1)) and p,p'-DDE was present at a maximum concentration of 2.9 ng g(-1) in a cork sample from Castile-La Mancha. However, all concentrations were well below the legal limit established by Regulation (EC) No. 396/2005 (10 ng g(-1) in foodstuffs). We can conclude, therefore, that the cork samples we studied complied with food safety standards.

  16. Chemically catalyzed uptake of 2,4,6-trinitrotoluene by Vetiveria zizanioides.

    PubMed

    Makris, Konstantinos C; Shakya, Kabindra M; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

    2007-07-01

    The efficiency of vetiver grass (Vetiveria zizanioides) in removing 2,4,6-trinitrotoluene (TNT) from aqueous media was explored in the presence of a common agrochemical, urea, used as a chaotropic agent. Chaotropic agents disrupt water structure, increasing solubilization of hydrophobic compounds (TNT), thus, enhancing plant TNT uptake. The primary objectives of this study were to: (i) characterize TNT absorption by vetiver in hydroponic media, and (ii) determine the effect of urea on chemically catalyzing TNT uptake by vetiver grass in hydroponic media. Results showed that vetiver exhibited a high TNT uptake capacity (1.026 mgg(-1)), but kinetics were slow. Uptake was considerably enhanced in the presence of urea, which significantly (p<0.001) increased the 2nd-order reaction rate constant over that of the untreated (no urea) control. Three major TNT metabolites were detected in the roots, but not in the shoot, namely 1,3,5-trinitrobenzene, 4-amino 2,6-dinitrotoluene, and 2-amino 4,6-dinitrotoluene, indicating TNT degradation by vetiver grass.

  17. Water Quality Criteria for 2,4-Dinitrotoluene and 2,6-Dinitrotoluene

    DTIC Science & Technology

    1987-08-01

    spiked water samples, with detection limits in the picogram (pg) range. Fine et al. (1984) report that a thermal energy analyzer ( TEA ) .m interfaced to...a gas chromatograph is capable of detecting 5 pg of 2,4- DNT in standard solutions. The use of this technique, as well as the combination of a TEA ...reported detection limits of 0.05 mg/L [(50 parts per billion No,. (ppb)] using CC/ TEA to determine the presence of nitroaromatics in ode biologically

  18. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C5Me4R)2UBr2, (C5Me4R)2U(O-2,6-iPr2C6H3)(Br), and [K(THF)][(C5Me4R)2UBr2] (R = Me, Et)

    DOE PAGES

    Lichtscheidl, Alejandro Gaston; Pagano, Justin K.; Scott, Brian Lindley; ...

    2016-01-06

    The organometallic uranium species (C5Me4R)2UBr2 (R = Me, Et) were obtained by treating their chloride analogues (C5Me4R)2UCl2 (R = Me, Et) with Me3SiBr. Treatment of (C5Me4R)2UCl2 and (C5Me4R)2UBr2 (R = Me, Et) with K(O-2,6-iPr2C6H3) afforded the halide aryloxide mixed-ligand complexes (C5Me4R)2U(O-2,6-iPr2C6H3)(X) (R = Me, Et; X = Cl, Br). Complexes (C5Me4R)2U(O-2,6-iPr2C6H3)(Br) (R = Me, Et) can also be synthesized by treating (C5Me4R)2U(O-2,6-iPr2C6H3)(Cl) (R = Me, Et) with Me3SiBr, respectively. Reduction of (C5Me4R)2UCl2 and (C5Me4R)2UBr2 (R = Me, Et) with KC8 led to isolation of uranium(III) “ate” species [K(THF)][(C5Me5)2UX2] (X = Cl, Br) and [K(THF)0.5][(C5Me4Et)2UX2] (X = Cl, Br), which canmore » be converted to the neutral complexes (C5Me4R)2U[N(SiMe3)2] (R = Me, Et). Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.« less

  19. 1,5-Dichloro-3(2,7),7(2,7)-dinaphthal-ena-2,4,6,8-tetra-oxa-1(2,6),5(2,6)-di(1,3,5-triazina)octa-phane.

    PubMed

    Sang, Qiu-Guang; Yang, Jing-Kui

    2011-09-01

    In the macrocyclic title compound, C(26)H(12)Cl(2)N(6)O(4), an O-atom-bridged calix[2]naphthalene-[2]triazine synthesized using a one-pot approach from naphthalene-2,7-diol and cyanuric chloride, the two isolated naphthalene planes and the two triazine-2,6-di-oxy planes adopt a 1,3-alternate configuration, with a dihedral angle of 84.10 (8)° between the naphthalene rings and a dihedral angle of 39.02 (14)° between the triazine rings. In the crystal, weak inter-molecular π-π stacking inter-actions are found between face-to-face naphthalene rings [centroid-centroid distance = 3.662 (7) Å].

  20. Measurement of the specific refractivities of CF4 and C2F6

    NASA Astrophysics Data System (ADS)

    Burner, A. W.; Goad, W. K.

    1980-07-01

    In order to relate the measured fringe shift of an interferometer to the density of a medium, the relation between density and refractive index, which is expressed by the specific refractivity, must be known. In the present paper, the specific refractivities of the wind tunnel test gases CF4 and C2F6 are determined in order to verify estimations based on the atomic refractivities of carbon and fluorine. A Twyman-Green two-beam interferometer with a 633-nm He-Ne laser light source was used to measure the specific refractivity as a function of fringe shift as the density of the gas was changed. Values of 0.122 and 0.131 cu cm/g were obtained for CF4 and C2F6 respectively at a temperature of 300 K, which are within 1% of the values computed from the atomic refractivities.

  1. Measurement of the specific refractivities of CF4 and C2F6

    NASA Technical Reports Server (NTRS)

    Burner, A. W.; Goad, W. K.

    1980-01-01

    In order to relate the measured fringe shift of an interferometer to the density of a medium, the relation between density and refractive index, which is expressed by the specific refractivity, must be known. In the present paper, the specific refractivities of the wind tunnel test gases CF4 and C2F6 are determined in order to verify estimations based on the atomic refractivities of carbon and fluorine. A Twyman-Green two-beam interferometer with a 633-nm He-Ne laser light source was used to measure the specific refractivity as a function of fringe shift as the density of the gas was changed. Values of 0.122 and 0.131 cu cm/g were obtained for CF4 and C2F6 respectively at a temperature of 300 K, which are within 1% of the values computed from the atomic refractivities.

  2. Decreased transpiration in poplar trees exposed to 2,4,6-trinitrotoluene

    SciTech Connect

    Thompson, P.L.; Ramer, L.A.; Guffey, A.P.; Schnoor, J.L.

    1998-01-01

    The improper handling of the toxic compound 2,4,6-trinitrotoluene (TNT) has led to the contamination of soil and groundwater, and the uptake of TNT by a variety of plants has been established. This article discusses the effects of various concentrations of the explosive 2,4,6-trinitrotoluene (TNT) on the transpiration of hybrid poplar trees growing in hydroponic media. Transpiration was measured daily by gravimetric means. The rapid removal of TNT from hydroponic solutions was a result of plant uptake and required a daily dosage of TNT to ensure a relatively constant exposure over time. Transpiration decreased with increasing TNT concentrations {ge}5 mg/L. Decreases in transpiration were accompanied by leaf chlorosis and abscission. A comparison between a laboratory study and a pilot-scale experiment showed good scale-up potential.

  3. Summary of External Peer Review and Public Comments and Disposition for 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8,-hexamethylcyclopenta[γ]-2-benzopyran (HHCB)

    EPA Pesticide Factsheets

    This document summarizes the public and external peer review comments that the EPA’s Office of Pollution Prevention and Toxics (OPPT) received for the draft work plan risk assessment for 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta--2-benzopyran

  4. FTY-720P Suppresses Osteoclast Formation by Regulating Expression of Interleukin-6 (IL-6), Interleukin-4 (IL-4), and Matrix Metalloproteinase 2 (MMP-2)

    PubMed Central

    Zhang, Dawei; Huang, Yongjun; Huang, Zongwen; Zhang, Rongkai; Wang, Honggang; Huang, Dong

    2016-01-01

    Background Osteoclast formation is closely related to the immune system. FTY720, a new immunosuppressive agent, has some functions in immune regulation. Its main active ingredients become FTY-720P in vivo by phosphorylation modification. The objective of this study was to determine the effects of FTY-720 with various concentrations on osteoclasts in vitro. Material/Methods RAW264.7 cells and bone marrow-derived mononuclear phagocytes (BMMs) were treated with RANKL to obtain osteoclasts in vitro. To investigate the role of FTY-720 in osteoclast formation, trap enzyme staining was performed and the number of osteoclasts was counted. Bone slices were stained with methylene blue, we counted the number of lacunae after bone slices were placed into dishes together with osteoclasts, and we observed the effect and function of FTY-720 in osteoclasts induced by RAW264.7 cells and BMMs. Then, we used a protein array kit to explore the effects of FTY-720P on osteoclasts. Results The results of enzyme trap staining and F-actin staining experiments show that, with the increasing concentration of FTY-720P, the number of osteoclast induced by RAW264.7 cells and BMMs gradually decreased (P<0.05), especially when the FTY-720P concentration reached 1000 ng/ml, and the number of osteoclasts formed was the lowest (P<0.05). With bone lacuna toluidine blue staining, the results also show that, with the increasing concentration of FTY-720P, the number of bone lacuna gradually decreased (P<0.05), and the number of lacunae is lowest when the concentration reached 800 ng/ml. Finally, protein array results showed that IL-4, IL-6, IL-12, MMP-2, VEGF-C, GFR, basic FGF, MIP-2, and insulin proteins were regulated after FTY-720P treatment. Conclusions FTY-720P can suppress osteoclast formation and function, and FTY-720P induces a series of cytokine changes. PMID:27344392

  5. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, Betty W.

    1986-01-01

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the present invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve much of the TATB, but readily dissolves these explosives.

  6. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, B.W.

    1984-11-29

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the subject invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve the TATB, but readily dissolves these interfering explosives.

  7. 2-Ethyl-6-methyl­anilinium 4-methyl­benzene­sulfonate

    PubMed Central

    Wu, Tian-Quan; Xia, Lin; Hu, Ai-Xi; Ye, Jiao

    2009-01-01

    The title compound, C9H14N+·C7H7SO3 −, contains a 2-ethyl-6-methyl­anilinium cation and a 4-methyl­benzene­sulfonic anion. The cations are anchored between the anions through N—H⋯O hydrogen bonds. Electrostatic and van der Waals inter­actions, as well as hydrogen bonds, maintain the structural cohesion. PMID:21581966

  8. Effect of structure on potency and selectivity in 2,6-disubstituted 4-(2-arylethenyl)phenol lipoxygenase inhibitors.

    PubMed

    Lazer, E S; Wong, H C; Wegner, C D; Graham, A G; Farina, P R

    1990-07-01

    A series of 2,6-disubstituted 4-(2-arylethenyl)phenols with potent human neutrophil 5-lipoxygenase (5-LO) inhibiting activity (IC50S in the 10(-7) M range) and weaker human platelet cyclooxygenase (CO) inhibiting activity (IC50S in the 10(-6) M range) is described. This series evolved from the chemical modification of an antiinflammatory dual CO/5-LO inhibitor, 2,6-di-tert-butyl-4-[2-(3-pyridyl)ethenyl]phenol (BI-L-93 BS). The potency and selectivity for 5-LO inhibition is greatly influenced by the nature of the substituents in the 2- and 6-positions. Other structure-activity relationships that determine relative 5-LO and CO potency are discussed. In vivo activity against antigen-induced leukotriene-mediated bronchoconstriction and cell influx in guinea pigs is presented. Representatives of the series are active when administered at 30 mg/kg ip.

  9. Crystal structure of 2-amino-7,7-dimethyl-5-oxo-4-(pyridin-4-yl)-5,6,7,8-tetrahydro-4 H-chromene-3-carbonitrile hemihydrate

    NASA Astrophysics Data System (ADS)

    Sharma, N.; Banerjee, B.; Brahmachari, G.; Kant, R.; Gupta, V. K.

    2015-12-01

    The title compound, 2-amino-7,7-dimethyl-5-oxo-4-(pyridin-4-yl)-5,6,7,8-tetrahydro-4 Hchromene-3-carbonitrile was synthesized by multicomponent reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure was determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. C2/ c, a = 22.010(6), b = 11.0364(10), c = 17.147(4) Å, β = 130.37(4)°, Z = 8, R = 0.0433 for 2377 observed reflections.

  10. The electronic structure and spin polarization of bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II)

    NASA Astrophysics Data System (ADS)

    Wisbey, David Scott

    The electronic structure of bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) (or Cu(CNdpm)2), (C24H36N2O 4Cu, Cu(II)) is spin polarized. Spin polarization was observed in molecular thin films of the metal organic molecule bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) (or Cu(CNdpm)2), (C24H36N2O 4Cu, Cu(II)) deposited on Co(111) using spin polarized photoemission. The spin polarization of Cu(CNdpm)2 deposited on Co(111) is coverage dependent, but deviates from the mean field (Ginzburg-Landau) model for a simple paramagnet on a ferromagnet. The results are, nonetheless, seen to be consistent with magnetometry and the predicted density of states. Weak ferromagnetic interaction is implicated between molecules by a positive Weiss constant. A nonzero coercivity is observed when an external magnetic field is applied. For Cu(CNdpm)2 deposited on Co(111), the induced spin polarization asymmetry was found to favor select molecular orbitals consistent with calculations. The results indicate a strong influence of the ferromagnetic Co(111) substrate and some extramolecular coupling. The metal-organic molecule bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) (Cu(CNdpm)2), (C24H36N2O 4Cu, Cu(II)), is a copper spin ½ system with a magnetic moment of 1.05+/-0.04 muB per molecule, slightly smaller than the 1.215+0.02 muB per molecule for the larger size copper spin ½ system C36H 48N4O4Cu * C4H8O (bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II) 4,4'-bipyridylethene * THF). There is generally good agreement between photoemission from vapor deposited thin films of the C24H36N 2O4Cu on Cu(111) and Co(111) and model calculations. Although this molecule is expected to have a gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, the molecule remains surprisingly well screened in the photoemission final state. Using light polarization dependent angle-resolved photoemission, the metal

  11. ZnO Catalyzed Efficient Synthesis of Some New 2-Substituted-4,6-diarylpyrimidines

    PubMed Central

    Ameta, K. L.; Kumar, Biresh; Rathore, Nitu S.

    2012-01-01

    A simple and efficient protocol is developed for the synthesis of 2-substituted-4,6-diarylpyrimidines from one-pot three-component reaction of 4′-hydroxy-3′,5′-dinitro substituted chalcones, S-benzylthiouronium chloride (SBT), and heterocyclic secondary amines (morpholine/pyrrolidine/piperidine) in the presence of 15 mol% of ZnO as a heterogeneous catalyst. The present methodology offers several advantages such as being a simple procedure as well as providing excellent yields, and short reaction time. The catalyst is inexpensive, stable, and can be easily recycled and reused for several cycles with consistent activity. PMID:24052838

  12. 2,4,6-trinitrotoluene transformation by a tropical marine yeast, Yarrowia lipolytica NCIM 3589.

    PubMed

    Jain, M R; Zinjarde, S S; Deobagkar, D D; Deobagkar, D N

    2004-11-01

    Yarrowia lipolytica NCIM 3589, a tropical marine degrader of hydrocarbons and triglycerides transformed 2,4,6-trinitrotoluene (TNT) very efficiently. Though this yeast could not utilize TNT as the sole carbon or nitrogen source, it was capable of reducing the nitro groups in TNT to aminodinitrotoluene (ADNT). In a complete medium containing glucose and ammonium sulphate as the available carbon and nitrogen sources respectively, the culture was able to completely transform 1 mM (227 ppm) of TNT under such conditions. A dual pathway was found to be functional, one of which resulted in the formation of the hydride-Meisenheimer complex (H(-)TNT) as a transiently accumulating metabolite that was subsequently denitrated to 2,4-dinitrotoluene (2,4-DNT), whereas the other pathway resulted in the formation of amino derivatives. The presence of increasing amounts of reducing equivalents in the form of glucose promoted better growth and the nitroreductases of this yeast to reduce the aromatic ring to 2,4-DNT although, the reduction of the nitro groups to amino groups was the major functional pathway. The ability of this tropical marine yeast to transform TNT into products such as 2,4-DNT which in turn could be metabolized by other microbes has implications in the use of this yeast for bioremediation of TNT polluted marine environments.

  13. Synthesis and photoluminescence of violet-blue phosphor Ba10(PO4)6F2: Eu2+

    NASA Astrophysics Data System (ADS)

    Huang, Yumei; Zhang, Xinguo; Pan, Jialiang

    2017-01-01

    A violet-blue phosphor of Ba10(PO4)6F2: Eu2+ was prepared by high-temperature solid state reaction. Luminescence, concentration quenching and thermal stability of Ba10(PO4)6F2: Eu2+ are systematically investigated. The phosphor exhibits a broadband UV absorption and a violet-blue emission peaking at 420 nm with corresponding CIE coordinates of (0.163, 0.024). It is found that Eu2+ ions occupy 9-coordinated Ba(1) and 7-coordinated Ba(2) site in Ba10(PO4)6F2, and therefore generate two emission sub-bands at 415 and 433 nm. The optimal concentration of Eu2+ is 5 mol% according to emission intensity and the quenching mechanism is verified to be a dipole-dipole interaction. Ba10(PO4)6F2: 0.05Eu2+ phosphor shows good thermal stability with 81% of room temperature intensity at 180 °C.

  14. CDK4/6 inhibitors in HER2-positive breast cancer.

    PubMed

    Corona, Silvia Paola; Ravelli, Andrea; Cretella, Daniele; Cappelletti, Maria Rosa; Zanotti, Laura; Dester, Martina; Gobbi, Angela; Petronini, Pier Giorgio; Generali, Daniele

    2017-04-01

    Notwithstanding the continuous progress made in cancer treatment in the last 20 years, and the availability of new targeted therapies, metastatic Breast Cancer (BC) is still incurable. Targeting the cell cycle machinery has emerged as an attractive strategy to tackle cancer progression, showing very promising results in the preclinical and clinical settings. The first selective inhibitors of CDK4/6 received breakthrough status and FDA approval in combination with letrozole (February 2015) and fulvestrant (February 2016) as first-line therapy in ER-positive advanced and metastatic BC. Considering the success of this family of compounds in hormone-positive BC, new possible applications are being investigated in other molecular subtypes. This review summarizes the latest findings on the use of CDK4/6 inhibitors in HER2 positive BC.

  15. First Observation of the nu(17)-nu(4) Difference Bands of Diborane (10)B(2)H(6) and (11)B(2)H(6).

    PubMed

    Flaud; Lafferty; Bürger; Pawelke; Domenech; Bermejo

    2000-10-01

    An analysis of the nu(17)-nu(4) difference bands near 800 cm(-1) of two isotopic species, (10)B(2)H(6) and (11)B(2)H(6), of diborane has been carried out using infrared spectra recorded with a resolution of ca. 0.003 cm(-1). In addition, the nu(17) band of (10)B(2)H(6) has been recorded and assigned. Since this band in (11)B(2)H(6) had already been studied (R. L. Sams, T. A. Blake, S. W. Sharpe, J.-M. Flaud, and W. J. Lafferty, J. Mol. Spectrosc. 191, 331-342 (1998)), it was possible to derive precise energy levels and Hamiltonian constants for the 4(1) vibrational states of both isotopic species. Copyright 2000 Academic Press.

  16. Synthesis of 3-amino-6-methyl-5-ethoxycarbonyl-4,7-dihydrothieno(2,3-b)pyridine derivatives

    SciTech Connect

    Krauze, A.A.; Liepin'sh, E.E.; Pelcher, Yu.E.; Dubur, G.Ya.

    1987-07-01

    The alkylation of piperidinium salts of substituted 1,4-dihydropyridine-2-thiols with chloroacetonitrile or iodoacetamide gave 2-cyanomethylthio- and 2-carbamoylmethylthio-substituted 6-methyl-4-acryl(pyridyl)-5-ethoxycarbonyl-3-cyano-1,4-dihydropyridines, which undergo intramolecular cyclization in basic media to give 3-amino-6-methyl-4-aryl(pyridyl)-5-ethoxycarbonyl-2-cyano(carbamoyl)-4,7-dihydrothieno(2,3-b)pyridines.

  17. Perpendicular magnetic anisotropy in Co2Fe0.4Mn0.6Si

    NASA Astrophysics Data System (ADS)

    Ludbrook, B. M.; Ruck, B. J.; Granville, S.

    2016-07-01

    We report perpendicular magnetic anisotropy (PMA) in the half-metallic ferromagnetic Heusler alloy Co2Fe0.4Mn0.6Si (CFMS) in a MgO/CFMS/Pd trilayer stack. PMA is found for CFMS thicknesses between 1 and 2 nm, with a magnetic anisotropy energy density of KU=1.5 ×106 erg/cm3 for tCFMS=1.5 nm. Both the MgO and Pd layer are necessary to induce the PMA. We measure a tunable anomalous Hall effect, where its sign and magnitude vary with both the CFMS and Pd thickness.

  18. Synthesis, antitubercular, antifungal and antibacterial activities of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one.

    PubMed

    Islam, Mojahidul; Siddiqui, Anees A; Rajesh, Ramadoss

    2008-01-01

    A series of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-ones has been synthesized. An appropriate aromatic hydrocarbon reacts with succinic anhydride in presence of AlCl3 to yield beta-aroyl propionic acid. The corresponding acid was cyclized with hydrazine hydrate to give 6-(substituted aryl)-2,3,4,5-tetrahydro-3-pyridazinone, which was heated on steam bath with phosphorus(V) oxychloride to yield 3-chloro 6-substituted phenyl pyridazine. This intermediate after reaction with hydrazine hydrate was converted into 3-hydrazino-6-substituted phenyl pyridazine. The resulting product was converted into 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one by reacting with substituted aroyl propionic acid. Spectral data (IR, NMR, mass spectra) confirmed the structures of the synthesized compounds. The synthesized compounds were investigated for their in vitro antitubercular, antifungal and antibacterial activities. The results indicated that the synthesized compounds have mild to potent activities with reference to their appropriate reference standards.

  19. A one-pot synthesis of 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane by hydrodeoxygenation of xylose using a palladium catalyst

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an effort to expand the number of biobased chemicals available from sugars, xylose has been converted to 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane in a one-pot reaction using palladium supported on silica-alumina as the catalyst. The title compound is produced in 35-40% yield under 7 MPa H2 pr...

  20. Crystal structure of hexa-prop-2-en-1-yl 4,4',4'',4''',4'''',4'''''-[1,3,5,2λ(5),4λ(5),6λ(5)-tri-aza-triphosphinine-2,2,4,4,6,6-hexa-yl-hexa-kis-(-oxy)]hexa-benzoate.

    PubMed

    Zhu, Jing; Li, Qian; Zheng, Fu-Wei; He, Juan; Qu, Ling-Bo

    2015-12-01

    In the title compound, C60H54N3O18P3, the central phosphazene ring is essentially planar, with an r.m.s. deviation of the six fitted atoms of 0.068 Å. The P-N bond lengths are within the narrow range 1.575 (2)-1.585 (2) Å, indicating the electrons are delocalized within the ring. The two ethenyl benzoate substituents on each P atom are located up and down with respect to the plane of the central P3N3 ring. The atoms of two terminal propenyl groups are disordered over two sets of sites, with refined site-occupancy ratios of 0.249 (12):0.751 (12) and 0.476 (9):0.524 (9). No intermolecular interactions are observed.

  1. Assembly of lipophilic tetranuclear (Cu4 and Zn4) molecular metallophosphonates from 2,4,6-triisopropylphenylphosponic acid and pyrazole ligands.

    PubMed

    Chandrasekhar, Vadapalli; Sasikumar, Palani; Boomishankar, Ramamoorthy; Anantharaman, Ganapathi

    2006-04-17

    A sterically hindered aryl phosphonic acid ArP(O)(OH)2 (2) (Ar = 2,4,6-isopropylphenyl) was synthesized and structurally characterized. ArP(O)(OH)2 forms an interesting hydrogen-bonded corrugated sheet-type supramolecular structure in the solid-state. A three-component reaction involving ArP(O)(OH)2, 3,5-dimethylpyrazole(DMPZH), and Cu(CH3COO)2.H2O produces the tetranuclear Cu(II) compound [Cu4(mu3-OH)2{ArPO2(OH)}2(CH3CO2)2(DMPZH)4][CH3COO]2.CH2Cl2 (3). A similar three-component reaction involving ArP(O)(OH)2, 3,5-dimethylpyrazole, and Zn(CH3COO)2.2H2O yields the tetranuclear Zn(II) compound [Zn4{ArPO3}2{ArPO2(OH)}2{DMPZH}4(DMPZ)2].5MeOH (4). While 3 has been found to have an asymmetric cage structure where two dinuclear copper cores are bridged by bidentate [ArPO2(OH)]- ligands, 4 possesses an open-book tricyclic structure composed of three fused metallophosphonate rings. Magnetic studies on 3 revealed antiferromagnetic behavior.

  2. Synthesis and crystal structure of a dinuclear yttrium(III)- (lanthanide(III)-) copper(II) complex with an unusual 2-methyl-2,4,6-tris(trifluoromethyl)-1,3-dioxane-4,6-diolato ligand

    SciTech Connect

    Wang, S.; Pang, Z.; Smith, K.D.L. )

    1993-11-10

    A dinuclear Ln[sup III]-Cu[sup II] complex with an unusual 2-methyl-2,4,6-tris(trifluoromethyl)-1,3-dioxane-4,6-diolato ligand has been synthesized and characterized structurally. The 1,3-dioxane-4,6-diolato ligand is the product of cycloaddition of 1,1,1-trifluoro-2,2-propanediol to a hexafluoroacetylacetonato ligand promoted by the metal complex.

  3. 1-(6-Bromo-3,4-dihydro-2H-1,4-benz­oxazin-4-yl)-2,2-dichloro­ethanone

    PubMed Central

    Ye, Fei; Li, Ying; Fu, Ying; Zhao, Li-Xia; Gao, Shuang

    2012-01-01

    The title compound, C10H8BrCl2NO2, is a target mol­ecule in our research on herbicide safeners. The oxazine ring has an envelope conformation, with puckering parameters close to ideal values [Q = 0.498 (3) Å, θ = 53.7 (3)° and ϕ = 253.4 (4)°]. The crystal structure is stabilized by C—H⋯O, C—H⋯Cl and C—H⋯Br inter­actions. PMID:22904947

  4. 1-(6-Bromo-3,4-dihydro-2H-1,4-benz-oxazin-4-yl)-2,2-dichloro-ethanone.

    PubMed

    Ye, Fei; Li, Ying; Fu, Ying; Zhao, Li-Xia; Gao, Shuang

    2012-08-01

    The title compound, C(10)H(8)BrCl(2)NO(2), is a target mol-ecule in our research on herbicide safeners. The oxazine ring has an envelope conformation, with puckering parameters close to ideal values [Q = 0.498 (3) Å, θ = 53.7 (3)° and ϕ = 253.4 (4)°]. The crystal structure is stabilized by C-H⋯O, C-H⋯Cl and C-H⋯Br inter-actions.

  5. Fire resistant polyamide based on 1-(diorganooxyphosphonyl)methyl-2,4- and -2,6diamino benzene

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, J. A. (Inventor); Kourtides, D. A. (Inventor)

    1986-01-01

    1-(Diorganooxyphosphonyl)methyl2,4- and-2,6diamino benzenes are reacted with polyacylhalides and optionally comonomers to produce polyamides which have desirable heat and fire resistance properties. These polymers are used to form fibers and fabrics where fire resistance properties are important, e.g., aircraft equipment and structures.

  6. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.8965 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  7. 2-Amino-4,6-dimethyl­pyridinium chloride dihydrate

    PubMed Central

    Al-Dajani, Mohammad T. M.; Talaat, Jamal; Salhin, Abdusalam; Hemamalini, Madhukar; Fun, Hoong-Kun

    2011-01-01

    In the title hydrated mol­ecular salt, C7H11N2 +·Cl−·2H2O, the pyridine N atom of the 2-amino-4,6-dimethyl­pyridine mol­ecule is protonated. The cation is essentially planar, with a maximum deviation of 0.006 (2) Å. In the crystal, the components are linked by N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds, thereby forming sheets lying parallel to (100). The crystal structure is further stabilized by aromatic π–π stacking inter­actions between the pyridinium rings [centroid–centroid distance = 3.4789 (9) Å]. PMID:22058738

  8. Facile Routes to NiF(6)(2)(-), AgF(4)(-), AuF(6)(-), and PtF(6)(-) Salts Using O(2)(+) as a Source of O(2)F in Anhydrous HF.

    PubMed

    Lucier, G. M.; Shen, C.; Elder, S. H.; Bartlett, N.

    1998-07-27

    O(2)(+) salts dissolved in liquid anhydrous hydrogen fluoride (aHF) at 20 degrees C or below oxidize aHF solutions of PtF(6)(2)(-) to PtF(6)(-). The parent base of O(2)(+) salts in aHF (O(2)F((solv))) generated with alkali fluoride is long-lived below -50 degrees C. An aHF solution of O(2)F((solv)) oxidizes Au(III) to Au(V) below -50 degrees C (2O(2)F((solv)) + AuF(4)(-)((solv)) --> AuF(6)(-)((solv)) +2O(2(g))). In situ generation of O(2)F((solv)) (O(2)(+)((solv)) + F(-)((solv)) --> O(2)F((solv))) with AgF(2) or NiF(2) in suspension in the aHF made basic with alkali fluoride gives AgF(4)(-) and NiF(6)(2)(-)salts. Low solubility of AAsF(6)(A = Cs, K) in aHF provides for the metathetical preparation of (O(2))(2)PdF(6) solutions in aHF. Removal of aHF, even at -60 degrees C, results in some O(2) and F(2) loss, to a composition approaching (O(2))PdF(5).

  9. Supramolecular hydrogen-bonded 1D arrangement in the crystals of 2,4-diamino-6-benzyl-1,3,5-triazine and 2,4-diamino-6-(4‧-methylbenzyl)-1,3,5-triazine

    NASA Astrophysics Data System (ADS)

    Janczak, Jan; Kubiak, Ryszard

    2009-02-01

    Two crystals of triazine derivatives, 2,4-diamino-6-benzyl-1,3,5-triazine ( 1) and 2,4-diamino-6-(4'-methylbenzyl)-1,3,5-triazine ( 2), are synthesised by a direct reaction of cyanoguanidine with the respective cyanocompounds. The IR spectra of the compounds are very similar. In the crystals the molecules are interconnected by N sbnd H⋯N hydrogen bonds forming one-dimensional hydrogen bonded polymer in 1 and three-dimensional hydrogen bonded network in 2. The arrangement of molecules in the crystal of 1 is denser than in 2 due to the π-π interactions between the π-clouds of the aromatic triazine rings that are absent in the crystal of 2. The geometries of the molecules in the crystals have been compared with those obtained by ab-initio molecular orbital calculated results that represent the geometries of molecules in the gas-phase.

  10. Poly[[penta­aqua­(μ4-pyridine-2,4,6-tri­carboxyl­ato)(μ3-pyridine-2,4,6-tri­carboxyl­ato)diterbium(III)] mono­hydrate

    PubMed Central

    Yu, Xiao-Ke; Zhu, Hong-Lin

    2012-01-01

    The three-dimensional title coordination polymer, {[Tb2(C8H2NO6)2(H2O)5]·H2O}n, was hydro­thermally synthesized by reacting the corresponding rare-earth salt with pyridine-2,4,6-tricarb­oxy­lic acid (H3ptc). There are two independent TbIII atoms in the structure, one of which is nine-coordinated, forming a monocapped NO8 square-anti­prism and the other is eight-coordinated exhibiting a 4,4-bicapped NO7 trigonal–prismatic environment. The complex units are inter­connected through the ptc3− anions acting in different coordination modes, resulting in a three-dimensional coordin­ation polymer. The crystal structure features extensive O—H⋯O hydrogen bonds. PMID:22904780

  11. Impact of ferrihydrite and anthraquinone-2,6-disulfonate on the reductive transformation of 2,4,6-trinitrotoluene by a gram-positive fermenting bacterium.

    PubMed

    Borch, Thomas; Inskeep, William P; Harwood, Jace A; Gerlach, Robin

    2005-09-15

    Batch studies were conducted to explore differences in the transformation pathways of 2,4,6-trinitrotoluene (TNT) reduction by a Gram-positive fermenting bacterium (Cellulomonas sp. strain ES6) in the presence and absence of ferrihydrite and the electron shuttle anthraquinone-2,6-disulfonate (AQDS). Strain ES6 was capable of TNT and ferrihydrite reduction with increased reduction rates in the presence of AQDS. Hydroxylaminodinitrotoluenes, 2,4-dihydroxylamino-6-nitrotoluene (2,4-DHANT), and tetranitroazoxytoluenes were the major metabolites observed in ferrihydrite- and AQDS-free systems in the presence of pure cell cultures. Ferrihydrite enhanced the production of amino derivatives because of reactions with microbially produced surface-associated Fe(ll). The presence of AQDS in the absence of ferrihydrite promoted the fast initial formation of arylhydroxylamines such as 2,4-DHANT. However, unlike in pure cell systems, these arylhydroxylamines were transformed into several unidentified polar products. When both microbially reduced ferrihydrite and AQDS were present simultaneously, the reduction of TNT was more rapid and complete via pathways thatwould have been difficult to infer solely from single component studies. This study demonstrates the complexity of TNT degradation patterns in model systems where the interactions among bacteria, Fe minerals, and organic matter have a pronounced effect on the degradation pathway of TNT.

  12. Tungsten phosphanylarylthiolato complexes [W{PhP(2-SC6H4)2-kappa3S,S',P} 2] and [W{P(2-SC6H4)3-kappa4S,S',S",P}2]: synthesis, structures and redox chemistry.

    PubMed

    Hildebrand, Alexandra; Lönnecke, Peter; Silaghi-Dumitrescu, Luminita; Hey-Hawkins, Evamarie

    2008-09-14

    PhP(2-SHC6H4)2 (PS2H2) reacts with WCl6 with reduction of tungsten to give the air-sensitive tungsten(IV) complex [W{PhP(2-SC6H4)2-kappa(3)S,S',P}2] (1). 1 is oxidised in air to [WO{PhPO(2-SC6H4)2-kappa(3)S,S',O}{PhP(2-SC6H4)2-kappa(3)S,S',P}] (2). The attempted synthesis of 2 by reaction of 1 with iodosobenzene as oxidising agent was unsuccessful. [W{P(2-SC6H4)3-kappa(4)S,S',S",P}2] (3) was formed in the reaction of P(2-SHC6H4)3 (PS3H3) with WCl6. The W(VI) complex 3 contains two PS3(3-) ligands, each coordinated in a tetradentate fashion resulting in a tungsten coordination number of eight. The reaction of 3 with AgBF4 yields the dinuclear tungsten complex [W2{P(2-SC6H4)3-kappa(4)S,S',S",P}3]BF4 (4). Complexes 1-4 were characterised by spectral methods and X-ray structure determination.

  13. Crystal structure of [Co(NH3)6][Co(CO)4]2

    PubMed Central

    Müller, Thomas G.; Kraus, Florian

    2015-01-01

    Hexaamminecobalt(II) bis­[tetra­carbonyl­cobaltate(-I)], [Co(NH3)6][Co(CO)4]2, was synthesized by reaction of liquid ammonia with Co2(CO)8. The CoII atom is coordinated by six ammine ligands. The resulting polyhedron, the hexa­amminecobalt(II) cation, exhibits point group symmetry -3. The Co-I atom is coordinated by four carbonyl ligands, leading to a tetra­carbonyl­cobaltate(−I) anion in the shape of a slightly distorted tetra­hedron, with point group symmetry 3. The crystal structure is related to that of high-pressure BaC2 (space group R-3m), with the [Co(NH3)6]2+ cations replacing the Ba sites and the [Co(CO)4]− anions replacing the C sites. N—H⋯O hydrogen bonds between cations and anions stabilize the structural set-up in the title compound. PMID:26594524

  14. Hydrogen-bond-directed assemblies of [La(18-crown-6)(H2O)4](BiCl6)·3H2O and [Nd(18-crown-6)(H2O)4](BiCl6)·3.5H2O regulated by different symmetries

    NASA Astrophysics Data System (ADS)

    Zhang, Shi-Yong; Li, Jian; Zeng, Ying; Wen, He-Rui; Du, Zi-Yi

    2016-12-01

    The reactions of La2O3 or Nd2O3 with BiCl3 and 18-crown-6 in the presence of excessive hydrochloric acid afforded two ion-pair compounds, namely [La(18-crown-6)(H2O)4](BiCl6)·3H2O (1) and [Nd(18-crown-6)(H2O)4](BiCl6)·3.5H2O (2). Although these two compounds contain similar building blocks, they exhibit two distinct hydrogen-bonded networks, which are mainly induced by the slightly different geometries of their large-sized cationic [Ln(18-crown-6)(H2O)4]3+ components.

  15. [Cu13 {S2 CN(n) Bu2 }6 (acetylide)4 ](+) : A Two-Electron Superatom.

    PubMed

    Chakrahari, Kiran Kumarvarma; Liao, Jian-Hong; Kahlal, Samia; Liu, Yu-Chiao; Chiang, Ming-Hsi; Saillard, Jean-Yves; Liu, C W

    2016-11-14

    The first structurally characterized copper cluster with a Cu13 centered cuboctahedral arrangement, a model of the bulk copper fcc structure, was observed in [Cu13 (S2 CN(n) Bu2 )6 (C≡CR)4 ](PF6 ) (R=C(O)OMe, C6 H4 F) nanoclusters. Four of the eight triangular faces of the cuboctahedron are capped by acetylide groups in μ3  fashion, and each of the six square faces is bridged by a dithiolate ligand in μ22 fashion, which leads to a truncated tetrahedron of twelve sulfur atoms. DFT calculations are fully consistent with the description of these Cu13 clusters as two-electron superatoms, that is, a [Cu13 ](11+) core passivated by ten monoanionic ligands, with an a1 HOMO containing two 1S jellium electrons.

  16. Analysis of 2,4,6-nonatrienal geometrical isomers from male flea beetles, Epitrix hirtipennis and E. fuscula.

    PubMed

    Zilkowski, Bruce W; Bartelt, Robert J; Vermillion, Karl

    2008-07-09

    Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2 E,4 E,6 Z) and (2 E,4 E,6 E) isomers as components of its male-produced aggregation pheromone. Here, we learned that the related species, E. hirtipennis, also emits a blend of 2,4,6-nonatrienals, including isomers not previously characterized. Patterns in emission and response suggest a pheromonal function. In an effort to acquire standards to aid in identification, we found that exposing (2 E,4 E,6 E)-2,4,6-nonatrienal (or other available 2,4,6-nonatrienals) to light readily generated a mixture of six geometrical isomers. Configurations of these were determined by NMR, and chromatographic properties (GC and HPLC) were documented. On the basis of chromatographic comparison to these standards, the most abundant, new compound from E. hirtipennis was concluded to be (2 E,4 Z,6 Z)-2,4,6-nonatrienal. Minor components from both E. hirtipennis and E. fuscula were also characterized. The analytical approach given here would also be of use in the food industry, where 2,4,6-nonatrienals are important as aroma compounds.

  17. Neuroprotective Activity of (1S,2E,4R,6R,-7E,11E)-2,7,11-cembratriene-4,6-diol (4R) in vitro and in vivo in Rodent Models of Brain Ischemia

    PubMed Central

    Xu, Zhenfeng; Mu, Chaofeng; Alvarez, Paloma; Ford, Byron D.; El Sayed, Khalid; Eterovic, Vesna A.; Ferchmin, Pedro A.; Hao, Jiukuan

    2015-01-01

    (1S,2E,4R,6R,-7E,11E)-2,7,11-cembratriene-4,6-diol (4R) is a precursor to key flavor ingredients in leaves of Nicotiana species. The present study shows 4R decreased brain damage in rodent ischemic stroke models. The 4R-pretreated mice had lower infarct volume (26.2±9.7 mm3) than those in control groups (untreated: 63.4±4.2 mm3, DMSO: 60.2±14.2 mm3). The 4R-posttreated rats also had less infarct volume (120±65 mm3) than those in the rats of DMSO group (291±95 mm3). The results from in vitro experiments indicate that 4R decreased neuro2a cells (neuroblastoma cells) apoptosis induced by oxygen glucose deprivation (OGD), and improved the population spikes (PSs) recovery in rat acute hippocampal slices under OGD; a phosphatidylinositol 3-kinase (PI3K) inhibitor, wortmannin, abolished the effect of 4R on PSs recovery. Furthermore, 4R also inhibited monocyte adhesion to bEND5 cells (murine brain-derived endothelial cells) and upregulation of intercellular adhesion molecule-1(ICAM-1) induced by OGD/reoxygenation (OGD/R), and restored the p-Akt level to pre-OGD/R values in bEND5 cells. In conclusion, the present study indicates that 4R has a protective effect in rodent ischemic stroke models. Inhibition of ICAM-1 expression and restoration of Akt phosphorylation are the possible mechanisms involved in cellular protection by 4R. PMID:25677097

  18. Photoluminescent and magnetic properties of lanthanide containing apatites: NaxLn10-x(SiO4)6O2-yFy, CaxLn10-x(SiO4)6O2-yFy (Ln = Eu, Gd, and Sm), Gd9.34(SiO4)6O2, and K1.32Pr8.68(SiO4)6O1.36F0.64.

    PubMed

    Latshaw, Allison M; Hughey, Kendall D; Smith, Mark D; Yeon, Jeongho; Zur Loye, Hans-Conrad

    2015-02-02

    Single crystals of NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Na(1.64)Gd(8.36)(SiO(4))(6)O(0.72)F(1.28), Gd(9.34)(SiO(4))(6)O(2), Ca(2.6)Eu(7.4)(SiO(4))(6)O(1.4)F(0.6), Ca(4.02)Sm(5.98)(SiO(4))(6)F(2), and K(1.32)Pr(8.68)(SiO(4))(6)O(1.36)F(0.64) and powders of NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Eu(9.34)(SiO(4))(6)O(2), and Gd(9.34)(SiO(4))(6)O(2) were synthesized via flux growth in selected alkali-fluoride melts. All of the compounds adopt the apatite structure with space group P6(3)/m. Luminescence and magnetic data were collected on NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Eu(9.34)(SiO(4))(6)O(2), and Gd(9.34)(SiO(4))(6)O(2). Luminescent data indicate that changing the cations and anions that surround the lanthanide site does not change the luminescent properties, making apatites versatile structures for optical materials.

  19. Vanadium(V) tartrato complexes: speciation in the H3O+(OH-)/H2VO4-/(2R,3R)-tartrate system and X-ray crystal structures of Na4[V4O8(rac-tart)2].12H2O and (NEt4)4[V4O8((R,R)-tart)2].6H2O (tart = C4H2O6(4-)).

    PubMed

    Schwendt, Peter; Tracey, Alan S; Tatiersky, Jozef; Gáliková, Jana; Zák, Zdirad

    2007-05-14

    A study of the aqueous H3O+(OH-)/H2VO4-/(2R,3R)-tartrate system has been performed at 273 K in a 1.0 mol/L Na+(Cl-) ionic medium using 51V NMR spectroscopy. In this relatively complicated system, more than 12 different species were observed. Ligand concentration, vanadate concentration, and pH variation studies were carried out, particularly for the range of pH 5.8-8.0 and for pH 2.4. Chemical shifts, vanadium-ligand stoichiometry, and also composition and formation constants for some, but not all, species are given. Despite some reduction of vanadium(V) to vanadium(IV) in an acidic medium at pH approximately 2.4, the stoichiometries of the principal species in solution at this pH were determined. Electrospray ionization mass spectra for some solutions were obtained and were in accordance with the conclusions drawn from the speciation studies. A series of crystalline vanadium(V) tartrato complexes M4[V4O8(tart)2].aq were also prepared and characterized. X-ray diffraction studies of Na4[V4O8(rac-tart)2].12H2O (1) and (NEt4)4[V4O8((R,R)-tart)2].6H2O (2) revealed unique tetranuclear [V4O8(tart)2]4- ions for which the {V4O4} rings have boat conformations.

  20. Ultralarge 3d/4f Coordination Wheels: From Carboxylate/Amino Alcohol-Supported {Fe4Ln2} to {Fe18Ln6} Rings

    PubMed Central

    2017-01-01

    A family of wheel-shaped charge-neutral heterometallic {FeIII4LnIII2}- and {FeIII18MIII6}-type coordination clusters demonstrates the intricate interplay of solvent effects and structure-directing roles of semiflexible bridging ligands. The {Fe4Ln2}-type compounds [Fe4Ln2(O2CCMe3)6(N3)4(Htea)42(EtOH), Ln = Dy (1a), Er (1b), Ho (1c); [Fe4Tb2(O2CCMe3)6(N3)4(Htea)4] (1d); [Fe4Ln2(O2CCMe3)6(N3)4(Htea)42(CH2Cl2), Ln = Dy (2a), Er (2b); [Fe4Ln2(O2CCMe3)4(N3)6(Htea)42(EtOH)·2(CH2Cl2), Ln = Dy (3a), Er (3b) and the {Fe18M6}-type compounds [Fe18M6(O2CCHMe2)12(Htea)18(tea)6(N3)6]·n(solvent), M = Dy (4, 4a), Gd (5), Tb (6), Ho (7), Sm (8), Eu (9), and Y (10) form in ca. 20–40% yields in direct reaction of trinuclear FeIII pivalate or isobutyrate clusters, lanthanide/yttrium nitrates, and bridging triethanolamine (H3tea) and azide ligands in different solvents: EtOH for the smaller {Fe4Ln2} wheels and MeOH/MeCN or MeOH/EtOH for the larger {Fe18M6} wheels. Single-crystal X-ray diffraction analyses revealed that 1–3 consist of planar centrosymmetric hexanuclear clusters built from FeIII and LnIII ions linked by an array of bridging carboxylate, azide, and aminopolyalcoholato-based ligands into a cyclic structure with a cavity, and with distinct sets of crystal solvents (2 EtOH per formula unit in 1a–c, 2 CH2Cl2 in 2, and 2 EtOH and 2 CH2Cl2 in 3). In 4–10, the largest 3d/4f wheels currently known, nearly linear Fe3 fragments are joined via mononuclear Ln/Y units by a set of isobutyrates and amino alcohol ligands into virtually planar rings. The magnetic properties of 1–10 reveal slow magnetization relaxation for {Fe4Tb2} (1d) and slow relaxation for {Fe4Ho2} (1c), {Fe18Dy6} (4), and {Fe18Tb6} (6). PMID:28135085

  1. Laboratory Spectra of Mixtures of CH4, C2H6, and CH3OH

    NASA Technical Reports Server (NTRS)

    Mastrapa, Rachel; Berry, Matthew T.; Sandford, Scott

    2011-01-01

    Infrared spectroscopy is commonly used as a tool for identifying the composition of objects in the Solar System and beyond. Using laboratory spectra, optical constants can be calculated and used to create model spectra for comparison to spectra obtained from infrared telescopes. In this study, the optical constants of mixtures of simple organics, including CH4, C2H6, and CH3OH were calculated from 15 to 70 K, in the frequency range of 9000-500 cm(sup -1) (1.1-20 micrometers), at a spectral resolution of 1 cm(sup -1).

  2. Synthesis, loading control and applications of 2,4,6-triphenylpyrilium as a solar photocatalyst

    NASA Astrophysics Data System (ADS)

    Vercher Perez, Rosa

    2005-07-01

    The technologies or processes of oxidation outpost that uses like energy the solar radiation for the degradation of polluting agents, suppose a novel alternative with important economic and environmental advantages. A proof of it has been the spectacular development which they have been these applications at world-wide level in the last years old, as well as the interest that the subject in international the scientific community has provoked. 2,4,6-trifenilpirilio by its singularity in this field has been chosen for this thesis the cation. It has been left from a study about the fotocatalitica activity of this cation, from the salt of hidrogenosulfato 2,4,6-trifenilpirilio and of the salt of tetrafluorborato 2,4,6-trifenilpirilio, when they act in homogenous phase on polluting agents, derivatives of dissolved fenolicos compounds in residual coming from the industry. In the first stage of the study I confirm the degradativo power of this cation but nevertheless a series of disadvantages in homogena phase was detected, had to the chemical characteristics of this organic species: hidrolitica opening of the ring and impossibility of reusability. With the purpose of correcting these problems it has been investigated and developed different methods from synthesis, in which this cation is supported in inorganic materials, concretely: silica gel, zeolites and sepiolitas. It has been come to the study, of individual form, the parameters that influence of significant form in the yield of the different processes and also has been verified the fotocatalitica activity of the new synthesized materials. In the developed methods it has been managed to totally control the amount of cation supported in the chosen materials and of this form to be able to know the effectiveness his activity like fotocatalizador in heterogenous phase. It is possible to emphasize, that the proposed procedures of synthesis, are quite simple and fast in his execution. The made studies have been carried

  3. Photophysics of poly(2,3,4,5,6-pentafluoro styrene) film

    NASA Technical Reports Server (NTRS)

    O'Connor, Donald B.; Scott, Gary W.; Coulter, Daniel R.; Miskowski, Vincent M.; Yavrouian, Andre

    1990-01-01

    The temperature-dependent steady-state emission, emission polarization anisotropy, and fluorescence-kinetics of poly(2,3,4,5,6-pentafluoro styrene) film are reported. Two interconverting excited-state conformations of the chromophore have been identified. The fluorescence of the higher energy conformation results from excitation on the red edge of the polymer absorption band at temperatures below 180 K. The energy barrier for conversion of the high energy conformer to the lower energy conformer is estimated to be E/hc = 27 + or - 7/cm. Electronic energy migration is not evident in this polymer.

  4. UV photolysis for enhanced phenol biodegradation in the presence of 2,4,6-trichlorophenol (TCP).

    PubMed

    Song, Jiaxiu; Wang, Wenbing; Li, Rongjie; Zhu, Jun; Zhang, Yongming; Liu, Rui; Rittmann, Bruce E

    2016-02-01

    A bacterial strain isolated from activated sludge and identified as Bacillus amyloliquefaciens could biodegrade phenol, but 2,4,6-trichlorophenol (TCP) inhibited phenol biodegradation and biomass growth. UV photolysis converted TCP into dichlorocatechol, monochlorophenol, and dichlorophenol, and this relieved inhibition by TCP. Phenol-removal and biomass-growth rates were significantly accelerated after UV photolysis: the monod maximum specific growth rate (μ(max)) increased by 9% after TCP photolysis, and the half-maximum-rate concentration (K(S)) decreased by 36%. Thus, the major benefit of UV photolysis in this case was to transform TCP into a set of much-less-inhibitory products.

  5. Glucopyranosyl-1,4-dihydropyridine as a new fluorescent chemosensor for selective detection of 2,4,6-trinitrophenol.

    PubMed

    Pinrat, Oran; Boonkitpatarakul, Kanokthorn; Paisuwan, Waroton; Sukwattanasinitt, Mongkol; Ajavakom, Anawat

    2015-03-21

    Glucopyranosyl-1,4-dihydropyridine (Glc-DHP) was synthesized as a new fluorescent chemosensor via cyclotrimerization of the β-amino acrylate in the presence of TiCl4. This DHP derivative is soluble in aqueous medium and the solution gives a blue fluorescence signal with a quantum yield of 29%. The fluorescence signal of Glc-DHP was selectively quenched by 2,4,6-trinitrophenol (TNP) with a quenching coefficient (Ksv) of 4.47 × 10(4) and at one of the best reported detection limits of 0.94 μM. The quenching mechanism was confirmed to be of the static type at the low concentration region (less than 50 μM) with the significant quenching effect of competitive absorption starting from the concentration of 50 μM. Even in the real sample (seawater and industrial water), the quenching efficiencies of TNP on the fluorescence emission of Glc-DHP were proven to be at the same level with that of the test in pure water, demonstrating the practicability of the detection. Furthermore, a fluorescent paper sensor could be prepared by immersing the paper into the Glc-DHP solution. The fluorescence of the paper sensor disappeared either by writing with TNP solution or by exposure to TNP vapor. This detection could be observed by the naked eye under black light. The pH effect was proven to be a substantial factor in the quenching mechanism, providing an accurate determination of TNP, 2,4-dinitrophenol (DNP) and 4-nitrophenol (4NP) in real mixed-samples.

  6. 40 CFR 721.5356 - Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Ethanol, 2,2â²2â³-nitrilotris... Substances § 721.5356 Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl... subject to reporting. (1) The chemical substance identified as ethanol, 2,22″-nitrilotris-, compound...

  7. 40 CFR 721.5356 - Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Ethanol, 2,2â²2â³-nitrilotris... Substances § 721.5356 Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl... subject to reporting. (1) The chemical substance identified as ethanol, 2,22″-nitrilotris-, compound...

  8. 40 CFR 721.5356 - Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Ethanol, 2,2â²2â³-nitrilotris... Substances § 721.5356 Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl... subject to reporting. (1) The chemical substance identified as ethanol, 2,22″-nitrilotris-, compound...

  9. 40 CFR 721.5356 - Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Ethanol, 2,2â²2â³-nitrilotris... Substances § 721.5356 Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl... subject to reporting. (1) The chemical substance identified as ethanol, 2,22″-nitrilotris-, compound...

  10. 40 CFR 721.5356 - Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Ethanol, 2,2â²2â³-nitrilotris... Substances § 721.5356 Ethanol, 2,22″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl... subject to reporting. (1) The chemical substance identified as ethanol, 2,22″-nitrilotris-, compound...

  11. Solvatochromism, hyperpolarizability, molecular and crystal structure of betaine dye 4-(2,4,6-triphenylpyridinium-1-yl)-phenolate

    NASA Astrophysics Data System (ADS)

    Stadnicka, Katarzyna; Milart, Piotr; Olech, Andrzej; Olszewski, Piotr K.

    2002-01-01

    Solvatochromic effect of 4-(2,4,6-triphenylpyridinium-1-yl)-phenolate hydrate, 1, was determined. CT absorption band, which gave the shift from 23,880 (in water solution) to 14,440 cm -1 (in anisole solution) allowed the molecular second order polarizability βCT to be estimated as 59.5×10 -30 cm 5 esu -1. The crystal structure of 1 was determined: C 29H 21NO·5.78H 2O; orthorhombic, C222 1, a=15.005(9), b=24.356(4), c=7.5097(9) Å; V=2744.5(17) Å 3, Z=4, DX=1.224 g cm -1; λ=0.71073 Å (Mo Kα); μ=0.087 mm -1; final R1=0.0551 for 2882 reflections [ I>2 σ( I)]. The molecules of 1, in an anti-parallel arrangement, form columns along the c-axis through stacking between the pyridinium ring and a phenyl ring in para position of the neighbouring molecule. Water molecules filling channels between the columns are disordered. Two of water molecules are connected by hydrogen bonds with negatively charged oxygen atom of 1. Powdered samples of 1 revealed only weak SHG response as measured using HRS method in relation to urea standard.

  12. Enantioselective [4 + 2] cycloaddition of cyclic N-sulfimines and acyclic enones or ynones: a concise route to sulfamidate-fused 2,6-disubstituted piperidin-4-ones.

    PubMed

    Liu, Yong; Kang, Tai-Ran; Liu, Quan-Zhong; Chen, Lian-Mei; Wang, Ya-Chuan; Liu, Jie; Xie, Yong-Mei; Yang, Jin-Liang; He, Long

    2013-12-06

    A concise route to valuable sulfamate-fused 2,6-disubstituted piperidin-4-ones or 2,3-dihydropyridin-4(1H)-ones in good yield with high diastereo- and enantioselectivity is presented. The combination of chiral primary amine and o-fluorobenzoic acid efficiently promoted an asymmetric [4 + 2] cycloaddition reaction of N-sulfonylimines and enones or ynones. The cycloaddition reaction between cyclic N-sulfonylimines and ynones is first reported.

  13. Synthesis and X-ray structural investigation of (C{sub 3}N{sub 6}H{sub 7}){sub 4}(CN{sub 3}H{sub 6}){sub 2}[UO{sub 2}(CrO{sub 4}){sub 4}] . 4H{sub 2}O and (H{sub 3}O){sub 6}[UO{sub 2}(CrO{sub 4}){sub 4}

    SciTech Connect

    Serezhkina, L. B.; Peresypkina, E. V.; Virovets, A. V.; Verevkin, A. G.; Pushkin, D. V.

    2009-03-15

    Single crystals of the compounds (C{sub 3}N{sub 6} H{sub 7}){sub 4}(CN{sub 3}H{sub 6}){sub 2}[UO{sub 2}(CrO{sub 4}){sub 4}] . 4H{sub 2}O (I) and (H{sub 3}O){sub 6}[UO{sub 2}(CrO{sub 4}){sub 4}] (II) are synthesized, and their structures are investigated using X-ray diffraction. Compound I crystallizes in the triclinic system with the unit cell parameters a = 6.3951(8) A, b = 10.8187(16) A, c = 16.9709(18) A, {alpha} = 93.674(4){sup o}, {beta} = 97.127(4){sup o}, {gamma} = 92.020(4){sup o}, space group, P1-barZ = 1, V = 1161.6(3) A{sup 3}, and R = 0.0470. Crystals of compound II belong to the monoclinic system with the unit cell parameters a = 14.3158(4) A, b = 11.7477(3) A, c = 13.1351(4) A, {beta}= 105.836(1){sup o}, space group C2/c, Z = 4, V = 2125.2(1) A{sup 3}, and R = 0.0213. The uranium-containing structural units of crystals I and II are mononuclear anionic complexes of the composition [UO{sub 2}(CrO{sub 4}){sub 4}]{sup 6-} with an island structure, which belong to the crystal-chemical group Am{sub 1}{sup 4} (A = UO{sub 2+}{sup 2}, M{sup 1} = CrO{sub 2-}{sup 4}) of the uranyl complexes. The [UO{sub 2}(CrO{sub 4}){sub 4}]{sup 6-} anionic complexes are joined into a three-dimensional framework through the electrostatic interactions with outer-sphere cations and a system of hydrogen bonds.

  14. Measurement of the Specific Refractivities of CF4 and C2F6

    NASA Technical Reports Server (NTRS)

    Burner, A. W.; Goad, W. K.

    1977-01-01

    In order to relate the measured fringe shift of an interferometer to density, the relation between density rho and refractive index n must be known. For gases where the refractive index is close to unity, this relation between density and refractive index is very closely approximated by (n - 1) = K rho where K is the specific refractivity, or the Gladstone-Dale constant. The specific refractivity, which is weakly dependent on wavelength and temperature, is readily available for a number of common test gases such as N2 and air. For more unique test gases such as CF4 and C2F6 for which refractive index data at optical wavelengths is not readily available, the constants can be estimated from the atomic refractivities of carbon and fluorine. In order to verify this estimation, a two-beam interferometer was used to experimentally determine the specific refractivities of CF4 and C2F6. This data was required for holographic interferometric measurements made at the Langley Hypersonic CF4 Tunnel. A Twyman-Green interferometer with a He-Ne laser light source of vacuum wavelength lambda equal to 633 nm was used to measure the constants. One beam of the two-beam interferometer passed through an optical cell of known inside length l which could be evacuated and slowly filled with the test gas to a density of 7.2 kg/cu m for CF4 or 5.7 kg/cu m for C2F6. If the refractive index (and hence density) is constant along the optical path through the cell, the fringe shift M and density change Delta rho are related M = 2Kl Delta rho/lambda for the double pass interferometer. Thus K can be determined by measuring the fringe shift as the density is changed. The output of a photodiode used to detect the fringe shift was recorded on a strip chart recorder. The rate of pressure increase of the test gas in the cell was controlled such that the fringes shifted at a rate of 0.5 to 1 fringe per sec. The pressure in the test cell was measured with a high accuracy quartz crystal pressure

  15. Growth and characterization of a new nonlinear optical organic crystal: 2,4,6-Trimethylacetanilide

    NASA Astrophysics Data System (ADS)

    Upadhyaya, V.; Prabhu, Sharada G.

    2015-09-01

    A new nonlinear optical organic material, 2,4,6-trimethylacetanilide (246TMAA), also known as N-[2,4,6- trimethylphenyl]acetamide, has been synthesized and grown as a single crystal by the slow evaporation technique by organic solvents. The grown crystals have been characterized by morphology study. The crystals are prismatic. Surface examination shows granular dendritic pattern in optical micrograph. The Scanning Electron Micrograph shows the layered growth of the crystal. The Differential Scanning Calorimeter plot shows no phase change until melting point (219°C). The density of the crystals is 1.1g/cc and the crystals are soft. The crystals are transparent in the visible region and in the ultra-violet region till 280 nm. 246TMAA crystallizes with 2 molecules in a monoclinic unit cell in the noncentrosymmetric point group m, space group Pn. Refractive indices of this optically biaxial crystal along the three crystallophysical axes have been measured at 633 nm. The optical second harmonic generation efficiency of the crystal at 1064 nm is about half that of the urea crystal, measured by powder method using Nd:YAG laser. The results show that the 246TMAA crystal can efficiently be used for up-conversion of infrared radiation into visible green light. The powder X-ray diffraction spectrum of the crystal has been obtained.

  16. Spectral Analysis and Crystal Structures of 4-(4-Methylphenyl)-6-Phenyl-2,3,3a, 4-Tetrahydro-1H-Pyrido[3,2,1-jk]Carbazole and 4-(4-Methoxyphenyl)-6-Phenyl-2,3,3a, 4-Tetrahydro-1H-Pyrido[3,2,1-jk]Carbazole.

    PubMed

    Kalyana Sundar, J; Natarajan, S; Chitra, S; Paul, Nidhin; Manisankar, P; Muthusubramanian, S; Suresh, J

    2011-01-01

    The crystal structures of 4-(4-methylphenyl)-6-phenyl-2,3,3a,4-tetrahydro-1H-pyrido[3,2,1-jk]carbazole (IIa) and 4-(4-methoxyphenyl)-6-phenyl-2,3,3a,4-tetrahydro-1H-pyrido[3,2,1-jk]carbazole (IIb) were elucidated by single crystal X-ray diffraction. Compound (IIa), C28H25N, crystallizes in the triclinic system, space group P-1, with a = 8.936(2) Å, b = 10.490(1) Å, c = 11.801(1) Å, α = 102.69(5) (°) ,  β = 103.27(3) (°) , γ = 93.80(1) (°) , and Z = 2. The compound (IIb), C28H25NO, crystallizes in the monoclinic system, space group P21/a, with a = 11.376(5) Å, b = 14.139(3) Å, c = 13.237(4) Å, β = 97.41(3) (°) , and Z = 4. In both the structures, the pyrido ring adopts a twist boat conformation and the carbazole molecule has the twisted envelope structure with C3 and C13 at the flap. No classical hydrogen bonds are observed in the crystal structures. Details of the preparation, structures, and spectroscopic properties of the new compounds are discussed.

  17. Synthesis of Substituted 2,3,5,6-tetraarylbenzo(1,2-b:5,4-b')difurans

    NASA Technical Reports Server (NTRS)

    Abdul-Aziz, Mahmoud; Auping, Judith V.; Meador, Michael A.

    1995-01-01

    A series of substituted 2,3,5,6-tetraarylbenzo(l,2-b:5,4-b')difurans 1 was synthesized. This synthesis is based upon the photocyclization of 2,5-dibenzoylresorcinol dibenzyl ethers to the corresponding tetrahydrobenzo(1,2-b:5,4-b')difurans. Treatment of the photoproducts with methanesulfonyl chloride in pyridine afforded 1 in overall yields ranging from 30-72%. A number of these compounds have high fluorescence quantum yields (of phi(sub f) = 0.76-0.90), and their fluorescence spectra exhibit large solvatochromic shifts. These compounds may be suitable for use as fluorescent probes.

  18. N-15 NMR study of the immobilization of 2,4- and 2,6-dinitrotoluene in aerobic compost.

    PubMed

    Thorn, Kevin A; Pennington, Judith C; Kennedy, Kay R; Cox, Larry G; Hayes, Charolett A; Porter, Beth E

    2008-04-01

    Large-scale aerobic windrow composting has been used to bioremediate washout lagoon soils contaminated with the explosives TNT (2,4,6-trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) at several sites within the United States. We previously used 15N NMR to investigate the reduction and binding of T15NT in aerobic bench-scale reactors simulating the conditions of windrow composting. These studies have been extended to 2,4-dinitrotoluene (2,4DNT) and 2,6-dinitrotoluene (2,6DNT), which, as impurities in TNT, are usually presentwherever soils have been contaminated with TNT. Liquid-state 15N NMR analyses of laboratory reactions between 4-methyl-3-nitroaniline-15N, the major monoamine reduction product of 2,4DNT, and the Elliot soil humic acid, both in the presence and absence of horseradish peroxidase, indicated that the amine underwent covalent binding with quinone and other carbonyl groups in the soil humic acid to form both heterocyclic and non-heterocyclic condensation products. Liquid-state 15N NMR analyses of the methanol extracts of 20 day aerobic bench-scale composts of 2,4-di-15N-nitrotoluene and 2,6-di-15N-nitrotoluene revealed the presence of nitrite and monoamine, but not diamine, reduction products, indicating the occurrence of both dioxygenase enzyme and reductive degradation pathways. Solid-state CP/MAS 15N NMR analyses of the whole composts, however, suggested that reduction to monoamines followed by covalent binding of the amines to organic matter was the predominant pathway.

  19. N-15 NMR study of the immobilization of 2,4- and 2,6-dinitrotoluene in aerobic compost

    USGS Publications Warehouse

    Thorn, K.A.; Pennington, J.C.; Kennedy, K.R.; Cox, L.G.; Hayes, C.A.; Porter, B.E.

    2008-01-01

    Large-scale aerobic windrow composting has been used to bioremediate washout lagoon soils contaminated with the explosives TNT (2,4,6- trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) at several sites within the United States. We previously used 15N NMR to investigate the reduction and binding of T15NT in aerobic bench -scale reactors simulating the conditions of windrow composting. These studies have been extended to 2,4-dinitrotoluene (2,4DNT) and 2,6-dinitrotoluene (2,6DNT), which, as impurities in TNT, are usually present wherever soils have been contaminated with TNT. Liquid-state 15N NMR analyses of laboratory reactions between 4-methyl-3-nitroaniline-15N, the major monoamine reduction product of 2,4DNT, and the Elliot soil humic acid, both in the presence and absence of horseradish peroxidase, indicated that the amine underwent covalent binding with quinone and other carbonyl groups in the soil humic acid to form both heterocyclic and non-heterocyclic condensation products. Liquid-state 15N NMR analyses of the methanol extracts of 20 day aerobic bench-scale composts of 2,4-di-15N-nitrotoluene and 2,6-di-15N-nitrotoluene revealed the presence of nitrite and monoamine, but not diamine, reduction products, indicating the occurrence of both dioxygenase enzyme and reductive degradation pathways. Solid-state CP/MAS 15N NMR analyses of the whole composts, however, suggested that reduction to monoamines followed by covalent binding of the amines to organic matter was the predominant pathway. ?? 2008 American Chemical Society.

  20. Study on the aerobic biodegradability and degradation kinetics of 3-NP; 2,4-DNP and 2,6-DNP.

    PubMed

    She, Zonglian; Xie, Tian; Zhu, Yingjie; Li, Leilei; Tang, Gaifeng; Huang, Jian

    2012-11-30

    Four biodegradability tests (BOD(5)/COD ratio, production of carbon dioxide, relative oxygen uptake rate and relative enzymatic activity) were used to determine the aerobic biodegradability of 3-nitrophenol (3-NP), 2,4-dinitrophenol (2,4-DNP) and 2,6-dinitrophenol (2,6-DNP). Furthermore, biodegradation kinetics of the compounds was investigated in sequencing batch reactors both in the presence of glucose (co-substrate) and with nitrophenol as the sole carbon source. Among the three tested compounds, 3-NP showed the best biodegradability while 2,6-DNP was the most difficult to be biodegraded. The Haldane equation was applied to the kinetic test data of the nitrophenols. The kinetic constants are as follows: the maximum specific degradation rate (K(max)), the saturation constants (K(S)) and the inhibition constants (K(I)) were in the range of 0.005-2.98 mg(mgSS d)(-1), 1.5-51.9 mg L(-1) and 1.8-95.8 mg L(-1), respectively. The presence of glucose enhanced the degradation of the nitrophenols at low glucose concentrations. The degradation of 3-NP was found to be accelerated with the increasing of glucose concentrations from 0 to 660 mg L(-1). At high (1320-2000 mg L(-1)) glucose concentrations, the degradation rate of 3-NP was reduced and the K(max) of 3-NP was even lower than the value obtained in the absence of glucose, suggesting that high concentrations of co-substrate could inhibit 3-NP biodegradation. At 2,4-DNP concentration of 30 mg L(-1), the K(max) of 2,4-DNP with glucose as co-substrate was about 30 times the value with 2,4-DNP as sole substrate. 2,6-DNP preformed high toxicity in the case of sole carbon source degradation and the kinetic data was hardly obtained.

  1. Spectral and quantum chemical studies on 1,3-bis(N(1)-4-amino-6-methoxypyrimidinebenzenesulfonamide-2,2,4,4-ethane-1,2-dithiol)-2,4-dichlorocyclodiphosph(V)azane and its erbium complex.

    PubMed

    Al-Mogren, Muneerah M; Alaghaz, Abdel-Nasser M A; El-Gogary, Tarek M

    2014-01-24

    Novel 1,3-bis(N(1)-4-amino-6-methoxypyrimidine-benzenesulfonamide-2,2,4,4-ethane-1,2-dithiol)-2,4-dichlorocyclodiphosph(V)azane (L), was prepared and their coordinating behavior towards the lanthanide ion Er(III) was studied. The structures of the isolated products are proposed based on elemental analyses, IR, UV-VIS., (1)H NMR, (13)C NMR, (31)P NMR, SEM, XRD, mass spectra, effective magnetic susceptibility measurements and thermogravimetric analysis (TGA). Computational studies have been carried out at the DFT-B3LYP/6-31G(d) level of theory on the structural and spectroscopic properties of L and its binuclear Er(III) complex. Different tautomers of the ligand were optimized at the ab initio DFT level. Keto-form structure is about 17.7 kcal/mol more stable than the enol form (taking zpe correction into account). Simulated IR frequencies were scaled and compared with that experimentally measured. TD-DFT method was used to compute the UV-VIS spectra which compared by the measured electronic spectra.

  2. Vasodilation effect of 2-benzyl-5-hydroxy-6-methoxy-3, 4-dihydroisoquinolin-1-one.

    PubMed

    Xu, Wei-Qi; Xiong, Zhi-Zheng; Chen, Ting-Ting; Gao, Xiao-Yan; Yu, Hang; Zhang, San-Qi; Cao, Yong-Xiao

    2012-08-01

    A 2-Benzyl-5-hydroxy-6-methoxy-3, 4-dihydroisoquinolin-1-one (ZC2) is a newly synthesized isoquinolinone compound. Its effect on vasodilation was evaluated in the present study. Isometric tension of rat artery rings was recorded by a sensitive myography system in vitro. The results showed that ZC2 relaxed rat mesenteric arteries pre-contracted by KCl, phenylephrine and 9, 11- dideoxy- 11α, 9α-epoxymethano-prostaglandin F2α (U46619), and abdominal aorta pre-contracted by KCl in a concentration-dependent manner. The ZC2-induced vasodilation was not affected by an endothelium denudation. ZC2 rightwards shifted the concentration-contraction curves, induced by KCl, phenylephrine, and 5-hydroxytryptamine (5-HT) in a non-parallel manner, which suggests that the vasodilation effects are most likely via voltage-dependent calcium channel (VDCC) and receptor-operated calcium channel (ROCC). Moreover, in Ca(2+)-free medium, ZC2 concentration-dependently depressed the vasoconstrictions induced by phenylephrine and CaCl(2), and decreased a contractile response induced by caffeine, which indicates a role of extracellular Ca(2+) influx inhibition through VDCC and ROCC, and intracellular Ca(2+) release from Ca(2+) store via the ryanodine receptors. Glibenclamide did not affect the vasodilation induced by ZC2, suggesting that ATP sensitive potassium channel is not involved in the vasodilation. The results indicate that ZC2 induces vasodilation by inhibiting the VDCC and ROCC, and receptormediated Ca(2+) influx and release. The inhibition of intracellular Ca(2+) release may be mediated via the ryanodine receptors.

  3. The Influence of Precipitation of Alpha2 on Properties and Microstructure in TIMETAL 6-4

    NASA Astrophysics Data System (ADS)

    Wu, Zhiwei; Qiu, Chunlei; Venkatesh, V.; Fraser, Hamish L.; Williams, R. E. A.; Viswanathan, G. B.; Thomas, Matthew; Nag, S.; Banerjee, Rajarshi; Loretto, Michael H.

    2013-04-01

    Samples of Hot Isostatically Pressed (HIPped) powder of TIMETAL 6-4 (Ti-6Al-4V, compositions in wt pct unless indicated), which was HIPped at 1203 K (930 °C), and of forged bar stock, which was slowly cooled from above the beta transus, were both subsequently held at 773 K (500 °C) for times up to 5 weeks and analyzed using scanning and transmission electron microscopy and atom probe analysis. It has been shown that in the samples aged for 5 weeks at 773 K (500 °C), there is a high density of alpha22, an ordered phase based on the composition Ti3Al) precipitates, which are typically 5 nm in size, and a significantly smaller density was present in the slowly cooled samples. The fatigue and tensile properties of samples aged for 5 weeks at 773 K (500 °C) have been compared with those of the HIPped powder and of the forged samples which were slowly cooled from just above the transus, and although no significant difference was found between the fatigue properties, the tensile strength of the aged samples was 5 pct higher than that of the as-HIPped and slowly cooled forged samples. The ductility of the forged samples did not decrease after aging at 773 K (500 °C) despite the strength increase. Transmission electron microscopy has been used to assess the nature of dislocations generated during tensile and fatigue deformation and it has been found that not just is planar slip observed, but dislocation pairs are not uncommon in samples aged at 773 K (500 °C) and some are seen in slowly cooled Ti6Al4V.

  4. Kobyashevite, Cu5(SO4)2(OH)6·4H2O, a new devilline-group mineral from the Vishnevye Mountains, South Urals, Russia

    NASA Astrophysics Data System (ADS)

    Pekov, Igor V.; Zubkova, Natalia V.; Yapaskurt, Vasiliy O.; Belakovskiy, Dmitriy I.; Chukanov, Nikita V.; Kasatkin, Anatoly V.; Kuznetsov, Aleksey M.; Pushcharovsky, Dmitry Y.

    2013-04-01

    A new mineral kobyashevite, Cu5(SO4)2(OH)6·4H2O (IMA 2011-066), was found at the Kapital'naya mine, Vishnevye Mountains, South Urals, Russia. It is a supergene mineral that occurs in cavities of a calcite-quartz vein with pyrite and chalcopyrite. Kobyashevite forms elongated crystals up to 0.2 mm typically curved or split and combined into thin crusts up to 1 × 2 mm. Kobyashevite is bluish-green to turquoise-coloured. Lustre is vitreous. Mohs hardness is 2½. Cleavage is {010} distinct. D(calc.) is 3.16 g/cm3. Kobyashevite is optically biaxial (-), α 1.602(4), β 1.666(5), γ 1.679(5), 2 V(meas.) 50(10)°. The chemical composition (wt%, electron-microprobe data) is: CuO 57.72, ZnO 0.09, FeO 0.28, SO3 23.52, H2O(calc.) 18.39, total 100.00. The empirical formula, calculated based on 18 O, is: Cu4.96Fe0.03Zn0.01S2.01O8.04(OH)5.96·4H2O. Kobyashevite is triclinic, Poverline{ 1 } , a 6.0731(6), b 11.0597(13), c 5.5094(6) Å, α 102.883(9)°, β 92.348(8)°, γ 92.597(9)°, V 359.87(7) Å3, Z = 1. Strong reflections of the X-ray powder pattern [ d,Å- I( hkl)] are: 10.84-100(010); 5.399-40(020); 5.178-12(110); 3.590-16(030); 2.691-16(20-1, 040, 002), 2.653-12(04-1, 02-2), 2.583-12(2-11, 201, 2-1-1), 2.425-12(03-2, 211, 131). The crystal structure (single-crystal X-ray data, R = 0.0399) contains [Cu4(SO4)2(OH)6] corrugated layers linked via isolated [CuO2(H2O)4] octahedra; the structural formula is CuCu4(SO4)2(OH)6·4H2O. Kobyashevite is a devilline-group member. It is named in memory of the Russian mineralogist Yuriy Stepanovich Kobyashev (1935-2009), a specialist on mineralogy of the Urals.

  5. 3,4-trans-4-Aryl-3-(1-pyridinio)-1,2,3,4-tetrahydropyridine-6-thiolates--new group of potential cardiotonic drugs.

    PubMed

    Krauze, A; Vītoliņa, R; Garaliene, V; Sīle, L; Klusa, V; Duburs, G

    2005-11-01

    3,4-trans-4-Aryl-3-(1-pyridinio)-1,2,3,4-tetrahydropyridine-6-thiolates 6-11 were prepared by a Michael reaction of N-acetonylpyridinium chloride with 3-aryl-2-cyanothioacrylamides or by a one-pot three-carbon condensation of N-acetonylpyridinium chloride, aromatic aldehyde and 2-cyanothioacetamide, and their cardiotonic properties were studied. 3,4-trans-5-cyano-2-hydroxy-2-methyl-4-(3-nitrophenyl)-3-(1-pyridinio)-1,2,3,4-tetrahydropyridine-6-thiolate 8 was considered as a lead compound in this series since it in vitro experiments (spontaneously beating rat atria) showed a cardiotonic activity similar to that of milrinone 2, however compound 8 induced activity at lover concentrations and without influence on chronotropic action of the heart. Unlike milrinone 2, thiolate 8 in vivo experiments (anaesthetized rats) did not influence blood pressure and heart rate. The acute toxicity of compound 8 was more than 10 times lower than that of milrinone 2.

  6. Down-regulation of intestinal apical calcium entry channel TRPV6 by ubiquitin E3 ligase Nedd4-2.

    PubMed

    Zhang, Wei; Na, Tao; Wu, Guojin; Jing, Haiyan; Peng, Ji-Bin

    2010-11-19

    Nedd4-2 is an archetypal HECT ubiquitin E3 ligase that disposes target proteins for degradation. Because of the proven roles of Nedd4-2 in degradation of membrane proteins, such as epithelial Na(+) channel, we examined the effect of Nedd4-2 on the apical Ca(2+) channel TRPV6, which is involved in transcellular Ca(2+) transport in the intestine using the Xenopus laevis oocyte system. We demonstrated that a significant amount of Nedd4-2 protein was distributed to the absorptive epithelial cells in ileum, cecum, and colon along with TRPV6. When co-expressed in oocytes, Nedd4-2 and, to a lesser extent, Nedd4 down-regulated the protein abundance and Ca(2+) influx of TRPV6 and TRPV5, respectively. TRPV6 ubiquitination was increased, and its stability was decreased by Nedd4-2. The Nedd4-2 inhibitory effects on TRPV6 were partially blocked by proteasome inhibitor MG132 but not by the lysosome inhibitor chloroquine. The rate of TRPV6 internalization was not significantly altered by Nedd4-2. The HECT domain was essential to the inhibitory effect of Nedd4-2 on TRPV6 and to their association. The WW1 and WW2 domains interacted with TRPV6 terminal regions, and a disruption of the interactions by D204H and D376H mutations in the WW1 and WW2 domains increased TRPV6 ubiquitination and degradation. Thus, WW1 and WW2 may serve as a molecular switch to limit the ubiquitination of TRPV6 by the HECT domain. In conclusion, Nedd4-2 may regulate TRPV6 protein abundance in intestinal epithelia by controlling TRPV6 ubiquitination.

  7. Thermally stable compositions including 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt

    DOEpatents

    Hiskey, Michael A.; Huynh, My Hang

    2010-01-26

    An explosive formulation including 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt and a high temperature binder is disclosed together with a process of preparing 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt.

  8. Enhancement of microbial 2,4,6-trinitrotoluene transformation with increased toxicity by exogenous nutrient amendment.

    PubMed

    Liang, Shih-Hsiung; Hsu, Duen-Wei; Lin, Chia-Ying; Kao, Chih-Ming; Huang, Da-Ji; Chien, Chih-Ching; Chen, Ssu-Ching; Tsai, Isheng Jason; Chen, Chien-Cheng

    2017-04-01

    In this study, the bacterial strain Citrobacter youngae strain E4 was isolated from 2,4,6-trinitrotoluene (TNT)-contaminated soil and used to assess the capacity of TNT transformation with/without exogenous nutrient amendments. C. youngae E4 poorly degraded TNT without an exogenous amino nitrogen source, whereas the addition of an amino nitrogen source considerably increased the efficacy of TNT transformation in a dose-dependent manner. The enhanced TNT transformation of C. youngae E4 was mediated by increased cell growth and up-regulation of TNT nitroreductases, including NemA, NfsA and NfsB. This result indicates that the increase in TNT transformation by C. youngae E4 via nitrogen nutrient stimulation is a cometabolism process. Consistently, TNT transformation was effectively enhanced when C. youngae E4 was subjected to a TNT-contaminated soil slurry in the presence of an exogenous amino nitrogen amendment. Thus, effective enhancement of TNT transformation via the coordinated inoculation of the nutrient-responsive C. youngae E4 and an exogenous nitrogen amendment might be applicable for the remediation of TNT-contaminated soil. Although the TNT transformation was significantly enhanced by C. youngae E4 in concert with biostimulation, the 96-h LC50 value of the TNT transformation product mixture on the aquatic invertebrate Tigriopus japonicas was higher than the LC50 value of TNT alone. Our results suggest that exogenous nutrient amendment can enhance microbial TNT transformation; however, additional detoxification processes may be needed due to the increased toxicity after reduced TNT transformation.

  9. A Versatile Synthesis of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)

    SciTech Connect

    Mitchell, A R; Pagoria, P F; Schmidt, R D; Coburn, M D; Lee, G S; Hsu, P C

    2006-04-06

    A safe and versatile synthesis of high-purity 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) based on vicarious nucleophilic substitution (VNS) chemistry has now been achieved. The starting material can be selected from a variety of inexpensive nitroarenes obtained from commercial suppliers (4-nitroaniline, picric acid) or U.S. stockpiles (ammonium picrate, TNT). The use of picric acid and ammonium picrate (Explosive D) is preferred as both compounds are directly converted to picramide in the presence of ammonium salts (diammonium hydrogen phosphate, ammonium carbamate) in sulfolane at elevated temperature. The picramide resulting from this process is directly converted to TATB using an optimized VNS reaction employing inexpensive hydroxylamine as the nucleophilic aminating reagent. A crucial element in our synthesis is a novel and efficient purification of TATB.

  10. Lanthanide complexes of 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one

    SciTech Connect

    Sitran, S; Fregona, D. ); Faraglia, G. )

    1990-01-01

    The title ligand (H(Dh), dehydroacetic acid) reacts with lanthanide(III) acetates in anhydrous methanol to form complexes of formula (M(Dh){sub 3}(MeOH)). When hydrated lanthanide acetates are used, hydrated compounds such as (Ce(Dh){sub 3}(H{sub 2}O)) or (Eu(Dh){sub 3}(H{sub 2}O)).H{sub 2}O are obtained. The reaction of lanthanum triacetate with H(Dh) yields the mixed complex (La(Dh){sub 2}(O{sub 2}CMe)), formation of the 1:3 complex also being unfavored in the presence of a large ligand excess. The complexes have been characterized by infrared and NMR ({sup 1}H and {sup 13}C) spectroscopy and by thermogravimetric measurements.

  11. Mutagenicities of 2,4- and 2,6-dinitrotoluenes and their reduced products in Salmonella typhimurium nitroreductase- and O-acetyltransferase-overproducing Ames test strains.

    PubMed

    Sayama, M; Mori, M; Shoji, M; Uda, S; Kakikawa, M; Kondo, T; Kodaira, K I

    1998-12-03

    Mutagenicities of 2,4- and 2,6-dinitrotoluene (2,4-and 2,6-DNT), and reduced metabolites formed by the incubation of 2,4- and 2,6-DNT with Salmonella typhimurium TA98, were tested using S. typhimurium YG strains possessing high level of nitroreductase (NR) and/or O-acetyltransferase (OAT) activities. All compounds tested showed greatest mutagenic activities toward strains YG1041 and YG1042, which possess high levels of NR and OAT activities. The relative mutagenic activities of 2,4-DNT and its related compounds toward YG1041 and YG1042 were aminonitrotoluenes<2,4-DNT<2,2'-dimethyl-5, 5'-dinitroazoxybenzene (2,2'-DM-5, 5'-DNAOB)4-hydroxylamino-2-nitrotoluene (4HA2NT)<4, 4'-dimethyl-3,3'-dinitroazoxybenzene (4,4'-DM-3,3'-DNAOB), and aminonitrotoluenes (2A4AT, 4A2NT)<2,4-DNT<4HA2NT4,4'-dimethyl-3, 3'-dinitroazoxybenzene (4,4'-DM-3,3'-DNAOB)<2HA4NT, respectively. In addition, the relative mutagenic activities of 2,6-DNT and its related compounds toward YG1041 and YG1042 were 2, 6-DNT<2-hydroxylamino-6-nitrotoluene (2HA6NT)<2,2'-dimethyl-3, 3'-dinitroazoxybenzene (2,2'-DM-3,3'-DNAOB), and 2-amino-6-nitrotoluene (2A6NT)<2,6-DNT<2HA6NT, respectively. These results, together with previous findings, suggested that aminohydroxylamino dimethylazoxybenzenes or aminohydroxylamino dimethylazobenzenes produced either by the reduction of hydroxylaminonitrotoluenes or by the reduction of dimethyl dinitroazoxybenzenes are active metabolites responsible for the mutagenic activities of 2,4- and 2,6-DNT.

  12. Vladimirivanovite, Na6Ca2[Al6Si6O24](SO4,S3,S2,Cl)2 · H2O, a new mineral of sodalite group

    NASA Astrophysics Data System (ADS)

    Sapozhnikov, A. N.; Kaneva, E. V.; Cherepanov, D. I.; Suvorova, L. F.; Levitsky, V. I.; Ivanova, L. A.; Reznitsky, L. Z.

    2012-12-01

    The results of an examination of vladimirivanovite, a new mineral of the sodalite group, found at the Tultui deposit in the Baikal region are discussed. The mineral occurs in the form of outer rims (0.01-3 mm thick) of lazurite, elongated segregations without faced crystals (0.2 to 3-4 mm in size; less frequently, 4 × 12-15 × 20 mm), and rare veinlets (up to 5 mm) hosted in calciphyre and marble. Vladimirivanovite is irregular and patchy dark blue. The mineral is brittle; on average, the microhardness VHN is 522-604, 575 kg/mm2; and the Mohs hardness is 5.0-5.5. The measured and calculated densities are 2.48(3) and 2.436 g/cm3, respectively. Vladimirivanovite is optically biaxial; 2 V meas = 63(±1)°, 2 V calc = 66.2°; the refractive indices are α = 1.502-1.507 (±0.002), N m = 1.509-1.514 (±0.002), and N g = 1.512-1.517 (±0.002). The chemical composition is as follows, wt %: 32.59 SiO2, 27.39 Al2O3, 7.66 CaO, 17.74 Na2O, 11.37 SO3, 1.94 S, 0.12 Cl, and 1.0 H2O; total is 99.62. The empirical formula calculated based on (Si + Al) = 12 with sulfide sulfur determined from the charge balance is Na6.36Ca1.52(Si6.03Al5.97)Σ12O23.99(SO4)1.58(S3)0.17(S2)0.08 · Cl0.04 · 0.62H2O; the idealized formula is Na6Ca2[Al6Si6O24](SO4,S3,S2,Cl)2 · H2O. The new mineral is orthorhombic, space group Pnaa; the unit-cell dimensions are a = 9.066, b = 12.851, c = 38.558 Å, V = 4492 Å3, and Z = 6. The strongest reflections in the X-ray powder diffraction pattern ( dÅ— I[ hkl]) are: 6.61-5[015], 6.43-11[020, 006], 3.71-100[119, 133], 2.623-30[20.12, 240], 2.273-6[04.12], 2.141-14[159, 13.15], 1.783-9[06.12, 04.18], and 1.606-6[080, 00.24]. The crystal structure has been solved with a single crystal. The mineral was named in memoriam of Vladimir Georgievich Ivanov (1947-2002), Russian mineralogist and geochemist. The type material of the mineral is deposited at the Mineralogical Museum of St. Petersburg State University, St. Petersburg, Russia.

  13. Further evidence for the tetraoxoiodate(V) anion, IO(4)(3-): hydrothermal syntheses and structures of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O and Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O.

    PubMed

    Sykora, Richard E; Wells, Daniel M; Albrecht-Schmitt, Thomas E

    2002-05-20

    The hydrothermal reaction of MoO(3) with BaH(3)IO(6) at 180 degrees C for 3 days results in the formation of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O (1). Under similar conditions, the reaction of Ba(OH)(2) x 8H(2)O with MoO(3) and Ba(IO(4))(2) x 6H(2)O yields Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O (2). The structure of 1, determined by single-crystal X-ray diffraction, consists of corner- and edge-sharing distorted MoO(6) octahedra that create two-dimensional slabs. Contained within this molybdenum oxide framework are approximately C(2v) tetraoxoiodate(V) anions, IO(4)(3-), that are involved in bonding with five Mo(VI) centers. The two equatorial oxygen atoms of the IO(4)(3-) anion chelate a single Mo(VI) center, whereas the axial atoms are mu(3)-oxo groups and complete the octahedra of four MoO(6) units. The coordination of the tetraoxoiodate(V) anion to these five highly electropositive centers is probably responsible for stabilizing the substantial anionic charge of this anion. The Ba(2+) cations separate the layers from one another and form long ionic contacts with neighboring oxygen atoms and a water molecule. Compound 2 also contains distorted MoO(6) octahedra. However, these solely edge-share with octahedral hexaoxoiodate(VII), IO(6)(5-), anions to form zigzagging one-dimensional, (1)(infinity)[(MoO(2))(IO(6))](3-), chains that are polar. These chains are separated from one another by Ba(2+) cations that are coordinated by additional water molecules. Bond valence sums for the iodine atoms in 1 and 2 are 5.01 and 7.03, respectively. Crystallographic data: 1, monoclinic, space group C2/c, a = 13.584(1) A, b = 7.3977(7) A, c = 20.736(2) A, beta = 108.244(2) degrees, Z = 4; 2, orthorhombic, space group Fdd2, a = 13.356(7) A, b = 45.54(2) A, c = 4.867(3) A, Z = 8.

  14. Dual Role of Endogenous Serotonin in 2,4,6-Trinitrobenzene Sulfonic Acid-Induced Colitis

    PubMed Central

    Rapalli, Alberto; Bertoni, Simona; Arcaro, Valentina; Saccani, Francesca; Grandi, Andrea; Vivo, Valentina; Cantoni, Anna M.; Barocelli, Elisabetta

    2016-01-01

    Background and Aims: Changes in gut serotonin (5-HT) content have been described in Inflammatory Bowel Disease (IBD) and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous 5-HT through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of IBD. Materials and Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135), 5-HT2A (Ketanserin), 5-HT3 (Ondansetron), 5-HT4 (GR125487), 5-HT7 (SB269970) receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylamino)tetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4, and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it. Conclusion: The prevailing deleterious contribution given by endogenous 5-HT to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders. PMID:27047383

  15. Initial reductive reactions in aerobic microbial metabolism of 2,4,6-trinitrotoluene.

    PubMed

    Vorbeck, C; Lenke, H; Fischer, P; Spain, J C; Knackmuss, H J

    1998-01-01

    Because of its high electron deficiency, initial microbial transformations of 2,4,6-trinitrotoluene (TNT) are characterized by reductive rather than oxidation reactions. The reduction of the nitro groups seems to be the dominating mechanism, whereas hydrogenation of the aromatic ring, as described for picric acid, appears to be of minor importance. Thus, two bacterial strains enriched with TNT as a sole source of nitrogen under aerobic conditions, a gram-negative strain called TNT-8 and a gram-positive strain called TNT-32, carried out nitro-group reduction. In contrast, both a picric acid-utilizing Rhodococcus erythropolis strain, HL PM-1, and a 4-nitrotoluene-utilizing Mycobacterium sp. strain, HL 4-NT-1, possessed reductive enzyme systems, which catalyze ring hydrogenation, i.e., the addition of a hydride ion to the aromatic ring of TNT. The hydride-Meisenheimer complex thus formed (H-TNT) was further converted to a yellow metabolite, which by electrospray mass and nuclear magnetic resonance spectral analyses was established as the protonated dihydride-Meisenheimer complex of TNT (2H-TNT). Formation of hydride complexes could not be identified with the TNT-enriched strains TNT-8 and TNT-32, or with Pseudomonas sp. clone A (2NT), for which such a mechanism has been proposed. Correspondingly, reductive denitration of TNT did not occur.

  16. Initial Reductive Reactions in Aerobic Microbial Metabolism of 2,4,6-Trinitrotoluene

    PubMed Central

    Vorbeck, Claudia; Lenke, Hiltrud; Fischer, Peter; Spain, Jim C.; Knackmuss, Hans-Joachim

    1998-01-01

    Because of its high electron deficiency, initial microbial transformations of 2,4,6-trinitrotoluene (TNT) are characterized by reductive rather than oxidation reactions. The reduction of the nitro groups seems to be the dominating mechanism, whereas hydrogenation of the aromatic ring, as described for picric acid, appears to be of minor importance. Thus, two bacterial strains enriched with TNT as a sole source of nitrogen under aerobic conditions, a gram-negative strain called TNT-8 and a gram-positive strain called TNT-32, carried out nitro-group reduction. In contrast, both a picric acid-utilizing Rhodococcus erythropolis strain, HL PM-1, and a 4-nitrotoluene-utilizing Mycobacterium sp. strain, HL 4-NT-1, possessed reductive enzyme systems, which catalyze ring hydrogenation, i.e., the addition of a hydride ion to the aromatic ring of TNT. The hydride-Meisenheimer complex thus formed (H−-TNT) was further converted to a yellow metabolite, which by electrospray mass and nuclear magnetic resonance spectral analyses was established as the protonated dihydride-Meisenheimer complex of TNT (2H−-TNT). Formation of hydride complexes could not be identified with the TNT-enriched strains TNT-8 and TNT-32, or with Pseudomonas sp. clone A (2NT−), for which such a mechanism has been proposed. Correspondingly, reductive denitration of TNT did not occur. PMID:16349484

  17. Treatment of 2,4,6-trinitrotoluene (TNT) red water by vacuum distillation.

    PubMed

    Zhao, Quanlin; Ye, Zhengfang; Zhang, Mohe

    2010-08-01

    2,4,6-Trinitrotoluene (TNT) red water from Chinese explosive industry was treated by vacuum distillation. The water quality before and after distillation was evaluated using high performance liquid chromatograph, UV-vis spectroscopy, Gas Chromatography/Mass Spectroscopy (GC/MS) and other physical and chemical analyses. The acute toxicity of TNT red water and its distillate was evaluated by determining the luminescence inhibition of Vibrio qinghaiensis sp. Nov. The results showed that the parameters except pH of the distillate met the criterion specified by the Chinese discharge standard for water pollutants from ordnance industry. Distillation removed chemical oxygen demand almost completely and the chrominance was reduced from 100,000 degrees to 17 degrees . The concentrations of 2,4-dinitrotoluene-3-sulfonate and 2,4-dinitrotoluene-5-sulfonate decreased from 20 x 10(3) and 31 x 10(3)mg L(-1) to 1.3 and 1.8 mg L(-1), respectively. GC/MS results showed that most of the organic components of TNT red water can be removed by distillation. The acute toxicity of water sample after distillation reduced 96%, compared with that of unprocessed TNT red water.

  18. Mechanistic and Kinetic Studies on the Homogeneous Gas-Phase Formation of PCTA/DTs from 2,4-Dichlorothiophenol and 2,4,6-Trichlorothiophenol

    PubMed Central

    Xu, Fei; Shi, Xiangli; Li, Yunfeng; Zhang, Qingzhu

    2015-01-01

    Polychlorinated thianthrene/dibenzothiophenes (PCTA/DTs) are sulfur analogues compounds to polychlorinated dibenzo-p-dioxin/dibenzofurans (PCDD/Fs). Chlorothiophenols (CTPs) are key precursors to form PCTA/DTs. 2,4-DCTP has the minimum number of Cl atoms to form 2,4,6,8-tetrachlorinated dibenzothiophenes (2,4,6,8-TeCDT), which is the most important and widely detected of the PCDTs. In this paper, quantum chemical calculations were carried out to investigate the homogeneous gas-phase formation of PCTA/DTs from 2,4-DCTP and 2,4,6-TCTP precursors at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. Several energetically feasible pathways were revealed to compare the formation potential of PCTA/DT products. The rate constants of the crucial elementary reactions were evaluated by the canonical variational transition-state (CVT) theory with the small curvature tunneling (SCT) correction over a wide temperature range of 600–1200 K. This study shows that pathways that ended with elimination of Cl step were dominant over pathways ended with elimination of the H step. The water molecule has a negative catalytic effect on the H-shift step and hinders the formation of PCDTs from 2,4-DCTP. This study, together with works already published from our group, clearly illustrates an increased propensity for the dioxin formation from CTPs over the analogous CPs. PMID:26343647

  19. Mechanistic and Kinetic Studies on the Homogeneous Gas-Phase Formation of PCTA/DTs from 2,4-Dichlorothiophenol and 2,4,6-Trichlorothiophenol.

    PubMed

    Xu, Fei; Shi, Xiangli; Li, Yunfeng; Zhang, Qingzhu

    2015-08-28

    Polychlorinated thianthrene/dibenzothiophenes (PCTA/DTs) are sulfur analogues compounds to polychlorinated dibenzo-p-dioxin/dibenzofurans (PCDD/Fs). Chlorothiophenols (CTPs) are key precursors to form PCTA/DTs. 2,4-DCTP has the minimum number of Cl atoms to form 2,4,6,8-tetrachlorinated dibenzothiophenes (2,4,6,8-TeCDT), which is the most important and widely detected of the PCDTs. In this paper, quantum chemical calculations were carried out to investigate the homogeneous gas-phase formation of PCTA/DTs from 2,4-DCTP and 2,4,6-TCTP precursors at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. Several energetically feasible pathways were revealed to compare the formation potential of PCTA/DT products. The rate constants of the crucial elementary reactions were evaluated by the canonical variational transition-state (CVT) theory with the small curvature tunneling (SCT) correction over a wide temperature range of 600-1200 K. This study shows that pathways that ended with elimination of Cl step were dominant over pathways ended with elimination of the H step. The water molecule has a negative catalytic effect on the H-shift step and hinders the formation of PCDTs from 2,4-DCTP. This study, together with works already published from our group, clearly illustrates an increased propensity for the dioxin formation from CTPs over the analogous CPs.

  20. Dielectric and magnetic behavior of nanocrystalline Cu0.4Co0.6Fe2O4 ferrite

    NASA Astrophysics Data System (ADS)

    Jadoun, Priya; Sharma, Jyoti; Prashant, B. L.; Dolia, S. N.; Bhatnagar, Deepak; Saxena, V. K.

    2016-05-01

    The mixed copper cobalt ferrite nanoparticles (Cu0.4Co0.6Fe2O4) have been synthesized by sol-gel auto combustion route with aqueous metal nitrates and citric acid as the precursor. The crystal structure has been analyzed by X-Ray diffraction (XRD) method. XRD reveals the formation of single phase cubic spinel structure. The Scanning Electron Microscopy (SEM) is used for morphological studies. The dielectric measurements at room temperature show the decrease in dielectric constant with increasing frequency which is attributed to Maxwell Wagner model and conduction mechanism in ferrites.The magnetic measurements show ferromagnetic behavior at room temperature and large coercivity is observed on cooling down the temperature to 20K.

  1. Synthesis, structural, optical and thermal studies on 3, 5-diethyl-2, 6-di (4-fluorophenyl)-4-oxopiperidinium chloride

    NASA Astrophysics Data System (ADS)

    Yuvaraj, V.; NizamMohideen, M.; Arockia doss, M.; Rajarajan, G.; Savithiri, S.; Murugakoothan, P.

    2017-02-01

    A new organic compound 3, 5-diethyl-2, 6-di (4-fluorophenyl)-4-oxopiperidinium chloride (DFOC) was synthesized and its crystal was grown from ethanolic solution adopting the slow evaporation solution growth technique. The structure of the grown crystal was analyzed by single crystal X-ray diffraction study. The compound crystallizes in the orthorhombic system with space group Pnma. 1H and 13C Fourier transform nuclear magnetic resonance spectra of DFOC were recorded to elucidate its molecular structure. UV-vis-NIR spectral study showed that the grown crystal is transparent in the entire visible region with the lower cut-off wavelength of 269 nm. The thermal stability of DFOC was studied by thermogravimetric and differential thermal (TG-DTA) analyses.

  2. Synthesis, structural, optical and thermal studies on 3,5-diethyl-2, 6-di (4-methoxyphenyl)-4-oxopiperidinium chloride

    NASA Astrophysics Data System (ADS)

    Yuvaraj, V.; Jauhar, RO. MU.; NizamMohideen, M.; Rajarajan, G.; Arockiadoss, M.; Savithiri, S.; Murugakoothan, P.

    2016-11-01

    A new organic compound 3, 5-diethyl-2, 6-di(4-methoxyphenyl)-4-oxopiperidinium chloride (DMOC) was synthesized and its crystals were grown from an ethanolic solution adopting slow evaporation solution growth technique. The structure of the grown crystal was analyzed by single crystal X-ray diffraction study. The compound crystallizes in the orthorhombic system with space group Pnma. 1H and 13C Fourier transform nuclear magnetic resonance spectra of DMOC were recorded to elucidate its molecular structure. UV-vis-NIR spectral study showed that the grown crystal is transparent in the entire visible region. The thermal stability of DMOC was studied by thermogravimetric and differential thermal (TG-DTA) analyses.

  3. Solvation dynamics of 4-(dicyanomethylene)-2-methyl-6-( p-dimethylaminostyryl)-4H-pyran (DCM) in a microemulsion

    NASA Astrophysics Data System (ADS)

    Pal, Samir Kumar; Mandal, Debabrata; Sukul, Dipankar; Bhattacharyya, Kankan

    1999-10-01

    The photophysical process of the laser dye 4-(dicyanomethylene)-2-methyl-6-( p-dimethylaminostyryl)-4H-pyran (DCM) is studied in aerosol-OT (AOT) microemulsions in n-heptane using picosecond spectroscopy. When AOT and water are added to a solution of DCM in n-heptane, some of the DCM molecules migrate from bulk n-heptane to the water pool. The absorption and emission peaks of the DCM molecules in the polar water pool are markedly red shifted from those in the bulk n-heptane and the emission intensity in the water pool is nearly 40 times higher. Dual emission is not observed in the microemulsions. DCM exhibits slow solvation dynamics in the water pool with an average solvation time of 1.23 ns.

  4. Solvatochromic behaviours and structure-spectra relationships of 4-carboxyl-2,6-dinitrophenylazohydroxynaphthalenes.

    PubMed

    Adegoke, Olajire A; Idowu, Olakunle S

    2010-02-01

    Comprehensive electronic absorption spectra of a new dye series, 4-carboxyl-2,6-dinitrophenylazohydroxynaphthalenes have been investigated in solvents of varying polarities. The solvent dependent UV-vis spectral shifts were analysed using some solvent physical parameters such as refractive index, dielectric function, hydrogen bonding acceptor ability, orientation of polarization and others. The observed spectral shifts were correlated with different solute-solvent interaction mechanisms using simple and multiple linear regression analyses. The results of the curve fitting coefficients enabled us to classify the various interactions of solvents with the dyes and relate the solvatochromic behaviours to the substituent effects on the dye molecules. Charge-transfer complexation occurring between one of the congeners and N,N'-dimethylformamide was extensively studied and discovered to be both concentration- and temperature-dependent. The electronic character and the chemical nature of the solvents as well as the chemical nature of the other substituents, apart from the common hydroxyl group, are important factors for the observed solvatochromic properties of the 4-carboxyl-2, 6-dinitrophenylazohydroxynaphthalenes.

  5. Adsorption of 2,4,6-trinitrotoluene on carboxylated porous polystyrene microspheres

    NASA Astrophysics Data System (ADS)

    Ye, Zhengfang; Meng, Qingqiang; Lu, Shengtao

    2012-02-01

    Large-pore-size (150 nm) polystyrene (PSt) microspheres were carboxylated with phthalic anhydride (PA) through Friedel-Crafts acetylation to study the adsorption of 2,4,6-trinitrotoluene (TNT) on this material from aqueous solution. The scanning electron microscope (SEM) images and mercury porosimetry measurements (MPM) of the microspheres showed that the pore structure was unchanged during the reaction. High adsorption capacity (11.2 mg g-1 of suction-dried adsorbent) and adsorption rate (33.9 mg g-1 h-1) for TNT were observed during the study. As shown by the adsorption isotherm, the adsorption of TNT on PA-PSt can be described by the Freundlich adsorption equation, indicating heterogeneous adsorption process. On-column adsorption of TNT on PA-PSt and elution indicated that TNT can be completely removed from aqueous solution and condensed into acetone.

  6. Construction of New Coordination Polymers from 4'-(2,4-disulfophenyl)- 3,2':6'3"-terpyridine: Polymorphism, pH-dependent syntheses, structures, and properties

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Li, Chao-Jie; He, Jia-En; Chen, Yin-Yu; Zheng, Sheng-Run; Fan, Jun; Zhang, Wei-Guang

    2016-01-01

    Nine new coordination compounds, namely, [Co(HDSPTP)2(H2O)44H2O (H2DSPTP=4'-(2,4-disulfophenyl)-3,2':6'3"-terpyridine, 1 and 2), {[Ni(DSPTP)(H2O)4]·3H2O}n (3), {[Cu(HDSPTP)2(H2O)3]·8H2O}n (4), {[Cu(HDSPTP)2(H2O)3]·6H2O}n (5), {[Cu(DSPTP)(H2O)2]·H2O}n (6), {[Zn(DSPTP)(H2O)22H2O}n (7), {[Cd(DSPTP)(H2O)22H2O}n (8), and [Ag2(DSPTP)(H2O)]n (9), were constructed based on a new ligand containing both terpyridyl and sulfo groups. The reactions of H2DSPTP with Co(NO3)2.6H2O resulted in two mononuclear complexes (compounds 1 and 2). They are polymorphisms that display different hydrogen bonding networks. They are selectively synthesized by altering the added alkalis. The reaction of H2DSPTP with Ni(NO3)2·6H2O resulted in a 1D "S-shaped" coordination chain (compound 3). The reactions of Cu(II) with H2DSPTP at different pH value resulted in the following three compounds: two kinds of 1D chains obtained at pH 3.0 and 4.0 for compounds 4 and 5, respectively, and a 3D framework based on binuclear ring units with 4-connected sra topology (Compound 6). The reactions of H2DSPTP with ds-block ions resulted in the following three compounds: a Zn(II) (compound 7) and a Cd(II) (compound 8) 3D frameworks with structures similar to that in compound 6, and a 3D framework based on tetranuclear Ag(I) SBUs with binodal (4,8)-connected flu type 3D framework topology. The structural diversity is mainly attributed to the rich coordination modes (from monodentate to μ7-mode) and conformations (cis-cis and cis-trans) of HDSPTP-/DSPTP2- ligands and the metal center and can be controllable synthesized by altering the alkalis, and pH value. Thermal stability of all compounds was performed, and the thermal behaviors of compounds 6 and 8 were further explored by PXRD. Compound 6 exhibits low thermal stability and undergo a crystalline-crystalline-amorphous phase transition as temperature increases from 25 °C to 200 °C, and show amorphous-crystalline phase transition when rehydrated

  7. Disproportional proton tautomers of pipecolic acid and 2,6-dichloro-4-nitrophenol in a 2:3 complex

    NASA Astrophysics Data System (ADS)

    Anioła, Michalina; Dega-Szafran, Zofia; Katrusiak, Andrzej; Komasa, Anna; Szafran, Mirosław

    2016-09-01

    A racemic mixture of (R/S)-pipecolic acid (piperidine-2-carboxylic acid, P2C) forms a stable crystalline aggregate with 2,6-dichloro-4-nitrophenol (DCNP) at the unusual 2:3 ratio (1). Complex 1 has been characterized by X-ray analysis, Raman, FTIR and NMR spectra, and its structure (2) has been optimized by the B3LYP/6-31G(d,p) approach. The crystals are monoclinic, P21/n space group. The piperidine rings adopt chair conformations with the equatorial positions of the carboxylic groups. A P2C zwitterion is linked to two 2,6-dichloro-4-nitrophenol molecules through two non-equivalent short COO⋯HO-C hydrogen bonds and a cation (P2C+H) is hydrogen bonded with the DCNP- anion. These P2C molecules are NH⋯O hydrogen bonded. The FTIR spectrum is in agreement with the X-ray studies. The 13C CP MAS spectrum confirms the presence of two different P2C and DCNP units in the complex. In the optimized structure of the isolate aggregate, three DCNP molecules are bonded to two pipecolic acid zwitterions. Charge delocalization has been analyzed using the Natural Bond Orbital (NBO) method.

  8. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloranisole

    DOEpatents

    Ott, Donald G.; Benziger, Theodore M.

    1990-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  9. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    DOEpatents

    Ott, Donald G.; Benziger, Theodore M.

    1991-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  10. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    DOEpatents

    Ott, D.G.; Benziger, T.M.

    1991-03-05

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole is described. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB. 8 figures.

  11. Spectroscopic studies and structure of 3-methoxy-2 -[(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde

    SciTech Connect

    Oezay, H.; Yildiz, M.; Uenver, H.; Durlu, T. N.

    2013-01-15

    The compound called 3-methoxy-2- [(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with hexachlorocyclotriphosphazene. It has been characterized by elemental analysis, MS, IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and UV-visible spectroscopic techniques. The structure of the title compound has been determind by X-ray analysis. Crystals are orthorhombic, space group P2{sub 1}2{sub 1}2{sub 1}, Z = 4, a = 7.705(1), b = 12.624(1), c = 17.825(2) A, R{sub 1} = 0.0390 and wR{sub 2} = 0.1074 [I > 2{sigma}(I)], respectively.

  12. Lahnsteinite, Zn4(SO4)(OH)6 · 3H2O, a new mineral from the Friedrichssegen Mine, Germany

    NASA Astrophysics Data System (ADS)

    Chukanov, N. V.; Rastsvetaeva, R. K.; Aksenov, S. M.; Pekov, I. V.; Belakovskiy, D. I.; Blass, G.; Möhn, G.

    2013-12-01

    A new mineral, lahnsteinite, has been found in the dump of the Friedrichssegen Mine, Bad Ems district, Rhineland-Palatinate (Rheinland-Pfalz), Germany. Lahnsteinite, occurring as colorless tabular crystals in the cavities of goethite, is associated with pyromorphite, hydrozincite, quartz, and native copper. The Mohs' hardness is 1.5; the cleavage is perfect parallel to (001). D calc = 2.995 g/cm3, D meas = 2.98(2) g/cm3. The IR spectrum is given. The new mineral is optically biaxial, negative, α = 1.568(2), β = 1.612(2), γ = 1.613(2), 2 V meas = 18(3)°, 2 V calc = 17°. The chemical composition (wt %, electron microprobe data; H2O was determined by gas chromatography of ignition products) is as follows: 3.87 FeO, 1.68 CuO, 57.85 ZnO, 15.83 SO3, 22.3 H2O, total is 101.53. The empirical formula is (Zn3.3Fe0.27Cu0.11)Σ3.91(S0.98O4)(OH)5 · 3H2.10O. The crystal structure has been studied on a single crystal. Lahnsteinite is triclinic, space group P1, a = 8.3125(6), b = 14.545(1), c = 18.504(2) Å, α = 89.71(1), β = 90.05(1), γ = 90.13(1)°, V = 2237.2(3) Å3, Z = 8. The strong reflections in the X-ray powder diffraction pattern [ d, Å ( I, %)] are: 9.30 (100), 4.175 (18), 3.476 (19), 3.290 (19), 2.723 (57), 2.624 (36), 2.503 (35), 1.574 (23). The mineral has been named after its type locality near the town of Lahnstein. The type specimen of lahnsteinite is deposited in the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, registration number 4252/1.

  13. Polarized Raman study of [N(C3H7)4]2Cd2Cl6 single crystal.

    PubMed

    Hannachi, N; Guidara, K; Bulou, A; Gargouri, M; Hlel, F

    2010-10-01

    Chemical preparation, mid-infrared and Raman spectra of [N(C(3)H(7))(4)](2)Cd(2)Cl(6) are presented. Polarized Raman spectra of oriented single crystals have been recorded in the range 7-3900 cm(-1) under various polarization configurations with regard to the symmetry and the numbers of several band modes observed in the Raman and infrared spectra. The obtained results are consistent with the theoretical predictions based on the infrared and Raman selection rules.

  14. 76 FR 81437 - Proposed Significant New Use Rule for Phenol, 2,4-dimethyl-6-(1-methylpentadecyl)-

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-28

    ... AGENCY 40 CFR Part 721 RIN 2070-AB27 Proposed Significant New Use Rule for Phenol, 2,4-dimethyl-6-(1...) for the chemical substance identified as phenol, 2,4-dimethyl-6-(1- methylpentadecyl)- (PMN P-94-209...? Under section 5(a)(2) of TSCA, EPA is re-proposing a SNUR previously proposed for phenol,...

  15. Inhibition of Bacterial Dihydrofolate Reductase by 6-Alkyl-2,4-diaminopyrimidines

    PubMed Central

    Nammalwar, Baskar; Bourne, Christina R.; Bunce, Richard A.; Wakeham, Nancy; Bourne, Philip C.; Ramnarayan, Kal; Mylvaganam, Shankari; Berlin, K. Darrell; Barrow, Esther W.; Barrow, William W.

    2012-01-01

    A series of (±)-6-alkyl-2,4-diaminopyrimidine-based inhibitors of bacterial dihydrofolate reductase (DHFR) have been prepared and evaluated for biological potency against Bacillus anthracis and Staphylococcus aureus. Biological studies reveal attenuated activity relative to earlier structures lacking substitution at C6 of the diaminopyrimidine moiety, though minimum inhibitory concentration (MIC) values are in the 0.125–8 μg/mL range for both organisms. This effect was rationalized from previous three-dimensional X-ray structure studies that indicate the presence of a side pocket containing two water molecules adjacent to the main binding pocket. Because of the hydrophobic nature of the substitutions at C6 the main interactions are with protein residues Leu20 and Leu28. These interactions lead to a minor conformational change in the protein, which opens the pocket containing these waters such that it is continuous with the main binding pocket. These water molecules are reported to play a critical role in the catalytic reaction. This highlights a new area for inhibitor expansion within the limited architectural variation at the catalytic site of bacterial DHFR. PMID:22930550

  16. Synthesis and reactivity of 6-substituted (Z)-2-En-4-ynoic acids

    SciTech Connect

    Struve, G.; Seltzer, S.

    1982-05-21

    Five different 6-substituted (Z)-2-en-4-ynoic acids (X = CH/sub 3/,CH/sub 3/CHOH, CH/sub 3/C(=CH/sub 2/), CH/sub 3/CHOAc, CH/sub 3/CO have been synthesized. The first three were formed by coupling of methyl(Z)-3-iodopropenoate and the appropriate cuprous acetylide followed by ester hydrolysis. The latter two were obtained from the hydroxyl compound by acetylation and oxidation, respectively. Three of the five compounds were shown to undergo lactonization by nucleophilic addition of the carboxlate group to the acetylenic carbon to yield 4-alkylidene-2-butenolide derivatives with specific trans addition. The rate of lactonization for the title compound (X = CH/sub 3/CO) is too fast to measure. The kinetics of lactonization for X = CH/sub 3/CHOAc and CH/sub 3/CHOH have been measured in water and dimethylformamide. The observed rate ratio for lactonization suggests the possibility of electrophilic catalysis by the neighboring acetate group.

  17. Structures of exocyclic R,R- and S,S-N(6),N(6)-(2,3-dihydroxybutan-1,4-diyl)-2'-deoxyadenosine adducts induced by 1,2,3,4-diepoxybutane.

    PubMed

    Kowal, Ewa A; Seneviratne, Uthpala; Wickramaratne, Susith; Doherty, Kathleen E; Cao, Xiangkun; Tretyakova, Natalia; Stone, Michael P

    2014-05-19

    1,3-Butadiene (BD) is an industrial and environmental chemical present in urban air and cigarette smoke, and is classified as a human carcinogen. It is oxidized by cytochrome P450 to form 1,2,3,4-diepoxybutane (DEB); DEB bis-alkylates the N(6) position of adenine in DNA. Two enantiomers of bis-N(6)-dA adducts of DEB have been identified: R,R-N(6),N(6)-(2,3-dihydroxybutan-1,4-diyl)-2'-deoxyadenosine (R,R-DHB-dA), and S,S-N(6),N(6)-(2,3-dihydroxybutan-1,4-diyl)-2'-deoxyadenosine (S,S-DHB-dA) [ Seneviratne , U. , Antsypovich , S. , Dorr , D. Q. , Dissanayake , T. , Kotapati , S. , and Tretyakova , N. ( 2010 ) Chem. Res. Toxicol. 23 , 1556 -1567 ]. Herein, the R,R-DHB-dA and S,S-DHB-dA adducts have been incorporated into the 5'-d(C(1)G(2)G(3)A(4)C(5)X(6)A(7)G(8)A(9)A(10)G(11))-3':5'-d(C(12)T(13)T(14)C(15)T(16)T(17)G(18)T(19)C(20)C(21)G(22))-3' duplex [X(6) = R,R-DHB-dA (R(6)) or S,S-DHB-dA (S(6))]. The structures of the duplexes were determined by molecular dynamics calculations, which were restrained by experimental distances obtained from NMR data. Both the R,R- and S,S-DHB-dA adducts are positioned in the major groove of DNA. In both instances, the bulky 3,4-dihydroxypyrrolidine rings are accommodated by an out-of-plane rotation about the C6-N(6) bond of the bis-alkylated adenine. In both instances, the directionality of the dihydroxypyrrolidine ring is evidenced by the pattern of NOEs between the 3,4-dihydroxypyrrolidine protons and DNA. Also in both instances, the anti conformation of the glycosyl bond is maintained, which combined with the out-of-plane rotation about the C6-N(6) bond, allows the complementary thymine, T(17), to remain stacked within the duplex, and form one hydrogen bond with the modified base, between the imine nitrogen of the modified base and the T(17) N3H imino proton. The loss of the second Watson-Crick hydrogen bonding interaction at the lesion sites correlates with the lower thermal stabilities of the R,R- and S,S-DHB-dA duplexes, as

  18. Multiple intramolecular hydrogen bonds in 2,4-di-tert-butyl-6-[N-(2,6-diisopropylphenyl)-P,P-diphenylphosphorimidoyl]phenol.

    PubMed

    Lee, Jong Dae; Suh, Il Hwan; Kang, Sang Ook

    2011-05-01

    The title compound, C(38)H(48)NOP, isolated from the reaction of (2-diphenylphosphanyl-4,6-di-tert-butyl)phenol with 2,6-diisopropylphenyl azide at 273 K, can act as an N,O-bidentate ligand. Crystal structure analysis shows a deviation from ideal tetrahedral symmetry around the P atom. The molecule exists as a monomer in the solid state, whose conformation is stabilized via multiple intramolecular hydrogen bonds. Geometric parameters from both experimental and theoretical calculations are compared.

  19. Nqrs Data for C10H12Br4N2Zn [Br4Zn·2(C5H6N)] (Subst. No. 1253)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C10H12Br4N2Zn [Br4Zn·2(C5H6N)] (Subst. No. 1253)

  20. Cork Taint of Wines: Role of the Filamentous Fungi Isolated from Cork in the Formation of 2,4,6-Trichloroanisole by O Methylation of 2,4,6-Trichlorophenol

    PubMed Central

    Álvarez-Rodríguez, María Luisa; López-Ocaña, Laura; López-Coronado, José Miguel; Rodríguez, Enrique; Martínez, María Jesús; Larriba, Germán; Coque, Juan-José R.

    2002-01-01

    Cork taint is a musty or moldy off-odor in wine mainly caused by 2,4,6-trichloroanisole (2,4,6-TCA). We examined the role of 14 fungal strains isolated from cork samples in the production of 2,4,6-TCA by O methylation of 2,4,6-trichlorophenol (2,4,6-TCP). The fungal strains isolated belong to the genera Penicillium (four isolates); Trichoderma (two isolates); and Acremonium, Chrysonilia, Cladosporium, Fusarium, Mortierella, Mucor, Paecilomyces, and Verticillium (one isolate each). Eleven of these strains could produce 2,4,6-TCA when they were grown directly on cork in the presence of 2,4,6-TCP. The highest levels of bioconversion were carried out by the Trichoderma and Fusarium strains. One strain of Trichoderma longibrachiatum could also efficiently produce 2,4,6-TCA in liquid medium. However, no detectable levels of 2,4,6-TCA production by this strain could be detected on cork when putative precursors other than 2,4,6-TCP, including several anisoles, dichlorophenols, trichlorophenols, or other highly chlorinated compounds, were tested. Time course expression studies with liquid cultures showed that the formation of 2,4,6-TCA was not affected by a high concentration of glucose (2% or 111 mM) or by ammonium salts at concentrations up to 60 mM. In T. longibrachiatum the O methylation of 2,4,6-TCP was catalyzed by a mycelium-associated S-adenosyl-l-methionine (SAM)-dependent methyltransferase that was strongly induced by 2,4,6-TCP. The reaction was inhibited by S-adenosyl-l-homocysteine, an inhibitor of SAM-dependent methylation, suggesting that SAM is the natural methyl donor. These findings increase our understanding of the mechanism underlying the origin of 2,4,6-TCA on cork, which is poorly understood despite its great economic importance for the wine industry, and they could also help us improve our knowledge about the biodegradation and detoxification processes associated with chlorinated phenols. PMID:12450804

  1. Synthesis, spectral and structural studies of alkyl 2-(3-alkyl-2,6-diarylpiperidin-4-ylidene)hydrazinecarboxylate derivatives: Crystal and molecular structure of methyl 2-(3-methyl-2,6-diphenylpiperidin-4-ylidene)hydrazinecarboxylate

    NASA Astrophysics Data System (ADS)

    Udhaya Kumar, C.; Sethukumar, A.; Velayutham Pillai, M.; Arul Prakasam, B.; Ramalingan, C.; Vidhyasagar, T.

    2016-05-01

    An efficient synthetic route with good overall yields to synthesize alkyl 2-(3-alkyl-2,6-diarylpiperidin-4-ylidene)hydrazinecarboxylates (7-14) is reported. All the synthesized compounds were characterized by their analytical and spectral (IR, 1H, 13C and 2D NMR) data. Single crystal X-ray structural analysis of compound 7, evidences that the configuration about Cdbnd N double bond is syn to C5 carbon (E-form) and exists in normal chair conformation with equatorial orientations of all the substituents.

  2. Frequency dependent study of the correlation functions in EPR spectroscopy--The Cole-Davidson approach. II. 2,N-(4-n-Butyl benzilidene) 4-amino 2,2,6,6-tetramethyl piperidine 1-oxide in toluene.

    PubMed

    Hwang, Jimmy S; Al-Janabi, Yahya T; Oweimreen, Ghassan A

    2010-11-01

    EPR linewidth measurements of 2,N-(4-n-butyl benzilidene) 4-amino 2,2,6,6-tetramethyl piperidine 1-oxide (BBTMPO) in toluene at 1 GHz (L-Band), 4 GHz (S-Band), 9 GHz (X-Band) and 34 GHz (Q-Band) microwave frequencies indicate the presence of a distribution of relaxation times. The empirical response parameter introduced by Cole-Davidson for the analysis of dielectric relaxation in liquids has been used for the analysis of EPR relaxation data in the L-Band and S-Band frequency regions. The Cole-Davidson parameter can assume values in the range 0 < β ≤ 1. When β = 1, one obtains the Debye-type spectral density. The calculated linewidth data at 1 GHz and 4 GHz agree with a Cole-Davidson parameter of 0.7 for the spherocone shaped BBMTPO solute. β < 1 at the L- and S-bands suggests the presence of an asymmetrical distribution of relaxation times associated with different modes of relaxation mechanisms or internal molecular motions. This study shows EPR experiments at low microwave frequencies are more sensitive to the shape of the correlation function. Differences between this study and an earlier study [6] on perdeuterated 2,2,6,6-tetramethly-4-piperidone N oxide (PD-Tempone) in toluene are attributed to the size of and absence of deuteration in the BBTMPO probe.

  3. Anaerobic biotransformation of 2,4-dinitrotoluene and 2,6-dinitrotoluene by Clostridium acetobutylicum: A pathway through dihydroxylamino intermediates

    SciTech Connect

    Hughes, J.B.; Wang, C.Y.; Zhang, C.

    1999-04-01

    Experiments were conducted to isolate and identify the intermediates and products of 2,4-dinitrotoluene and 2,6-dinitrotoluene metabolism by Clostridium acetobutylicum. Transformation of both dinitrotoluenes initially resulted in the formation of hydroxylaminonitrotoluenes. Subsequent transformation favored the formation of dihydroxylaminotoluenes, with a limited reduction to aminonitrotoluene isomers. In cell cultures, metabolism beyond the level of dihydroxylaminotoluene was not observed. In cell extracts, where activity could be maintained for periods in excess of those in cell cultures, further transformation yielded aminohydroxylaminotoluenes and eventually diaminotoluenes. These findings further demonstrate the potential for hydroxylamines to be significant intermediates of nitroaromatic transformation under anaerobic fermentative conditions. Interestingly, the rearrangement of dihydroxylaminotoluenes was not observed, as was the case in previous studies of 2,4-dihydroxylamino-6-nitrotoluene metabolism. Dihydroxylaminotoluenes were found to be quite unstable, decomposing rapidly upon exposure to oxygen, complicating the assessment of their fate in remediation processes.

  4. Plant Uptake of 2,4,6-Trinitrotoluene, 4-Amino-2,6-Dinitrotoluene, and 2-Amino-4,6-Dinitrotoluene Using 14C-Labeled and Unlabeled Compounds

    DTIC Science & Technology

    1988-11-01

    and Physical Characteristics of Test Soils Parameter Clay Silt pH 5.71 4.54 Particle size Percent sand 8.70 9.37 Percent silt 36.90 73.13 Percent clay ...showed significantly greater yields in clay than in silt. 59. Yields for all control and treated pots in this study were signifi- cantly lower than (about...and in TNT- treated clay . However, uptake levels represented less than 1 percent of the total 14C available in each pot (based on T65 carbon train

  5. Diastereoselective synthesis of 2-arylmethylene-6-hydroxyspiro[4.5]deca-7-ones via FeCl3·6H2O-catalyzed spiroannulation/hydride transfer of 6-(5-arylpent-4-yn-1-yl)-7-oxabicyclo[4.1.0]heptan-2-ols.

    PubMed

    Lin, Hsin-Hui; Lee, Kuan-Yi; Chen, Yin-An; Liu, Chi-Fan; Yeh, Ming-Chang P

    2014-12-05

    In the presence of a catalytic amount of FeCl3·6H2O, 6-(5-arylpent-4-yn-1-yl)-7-oxabicyclo[4.1.0]heptan-2-ols underwent attack of the pendant acetylene at the iron-activated oxirane to give a vinylic carbocation. Hydride transfer from the carbinol carbon to the newly formed cation center furnished 2-arylmethylene-6-hydroxyspiro[4.5]deca-7-ones in excellent stereoselectivity and good yields.

  6. Studies in iridoid synthesis. Chemoselective transformations of cis-1,2,4,6-tetrahydrophthalic anhydride.

    PubMed

    Stevens, Anne T; Bull, James R; Chibale, Kelly

    2008-02-07

    In the course of synthetic studies towards the development of diastereoselective routes to secoiridoid aglycones, cis-1,2,4,6-tetrahydrophthalic anhydride was transformed into the corresponding lactone cis-3a,4,7,7a-tetrahydro-3H-isobenzofuran-1-one, which served as a key precursor for a variety of chemoselective synthetic manipulations. Unsuccessful formylation of an ester intermediate resulted in a (E/Z) mixture of vinyl alcohols which were protected as acetates and as a single p-methoxybenzyl (PMB) ether (E) isomer. Dihydroxylation of the cyclohexene motif using OsO(4) led to the unexpected deprotection of the PMB ether. On the other hand, successful formylation of a suitably silyl protected lactonised intermediate was achieved using tert-butoxybis(dimethylamino)methane, or Bredereck's reagent. Tetrabutylammonium fluoride (TBAF) deprotection of a methoxyethoxymethyl (MEM)-ether intermediate serendipitously afforded an approximately 1 : 1 mixture of pyrano-pyranones, which are products of a seldom encountered intramolecular Michael addition, using an oxygen donor, to the terminus of an alpha,beta-unsaturated system, followed by beta-elimination of the MEM moiety.

  7. High uptake of 2,4,6-trinitrotoluene by vetiver grass--potential for phytoremediation?

    PubMed

    Makris, Konstantinos C; Shakya, Kabindra M; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

    2007-03-01

    2,4,6-Trinitrotoluene (TNT) is a potent mutagen, and a Group C human carcinogen that has been widely used to produce munitions and explosives. Vast areas that have been previously used as ranges, munition burning, and open detonation sites are heavily contaminated with TNT. Conventional remediation activities in such sites are expensive and damaging to the ecosystem. Phytoremediation offers a cost-effective, environment-friendly solution, utilizing plants to extract TNT from contaminated soil. We investigated the potential use of vetiver grass (Vetiveria zizanioides) to effectively remove TNT from contaminated solutions. Vetiver grass plants were grown in hydroponic systems containing 40 mg TNTL(-1) for 8d. Aqueous concentrations of TNT reached the method detection limit ( approximately 1 microg L(-1)) within the 8-d period, demonstrating high affinity of vetiver for TNT, without any visible toxic effects. Results from this preliminary hydroponic study are encouraging, but in need of verification using TNT-contaminated soils.

  8. Fundamental Kinetics Database Utilizing Shock Tube Measurements (Volumes 1, 2, 3, 4, and Volume 6)

    DOE Data Explorer

    Davidson, D. F.; Hanson, R. K

    The data from shock tube experiments generally takes three forms: ignition delay times, species concentration time-histories and reaction rate measurements. Volume 1 focuses on ignition delay time data measured and published by the Shock Tube Group in the Mechanical Engineering Department of Stanford University. The cut-off date for inclusion into this volume was January 2005. Volume 2 focuses on species concentration time-histories and was cut off December 2005. The two volumes are in PDF format and are accompanied by a zipped file of supporting data. Volume 3 was issued in 2009. Volume 4, Ignition delay times measurements came out in May, 2014, along with Reaction Rates Measurements, Vol 6. Volume 5 is not available at this time.

  9. Sliding and Rocking of Unanchored Components and Structures: Chapter 7.6 ASCE 4 Revision 2

    SciTech Connect

    S. R. Jensen

    2011-04-01

    Chapter 7.6 of ASCE 4-Rev 2, Seismic Analysis of Safety-Related Nuclear Structures: Standard and Commentary, provides updated guidance for analysis of rocking and sliding of unanchored structures and components subjected to seismic load. This guidance includes provisions both for simplified approximate energy-based approaches, and for detailed probabilistic time history analysis using nonlinear methods. Factors to be applied to the analytical results are also provided with the intent of ensuring achievement of the 80% non-exceedence probability target of the standard. The present paper surveys the published literature supporting these provisions. The results of available testing and analysis are compared to results produced by both simplified and probabilistic approaches. In addition, adequacy of the standard's provisions for analysis methods and factors is assessed. A comparison is made between the achieved level of conservatism and the standard's non-exceedence probability target.

  10. Solvothermal synthesis, crystal structure and properties of [Mn(C 6H 18N 4)] 4Mn 2Sb 4S 12 containing the new hetero-metallic [Mn 2Sb 4S 12] core

    NASA Astrophysics Data System (ADS)

    Schaefer, Michael; Näther, Christian; Bensch, Wolfgang

    2003-08-01

    The novel thioantimonate(III) [Mn(C 6H 18N 4)] 4Mn 2Sb 4S 12 was synthesised under solvothermal conditions by reacting Mn, Sb and S in an aqueous solution of tren (=tris(2-aminoethyl)amine). In the structure MnS 4 tetrahedra and SbS 3 pyramids are linked via common corners and edges to form a new hetero-metallic [Mn 2Sb 4S 12] core. The [Mn(C 6H 18N 4)] 2+ cations are located at the periphery of the core and are bound to the [Mn 2Sb 4S 12] unit via two S atoms. Interesting features of the structure are two large angles around S atoms connecting neighboured MnS 4 tetrahedra. The competition between interatomic bonding interactions and steric requirements are responsible for this observation. The thermal decomposition proceeds in one step involving a complex redox reaction.

  11. Induction of apoptosis of 2,4',6-trihydroxybenzophenone in HT-29 colon carcinoma cell line.

    PubMed

    Lay, Ma Ma; Karsani, Saiful Anuar; Malek, Sri Nurestri Abd

    2014-01-01

    2,4',6-Trihydroxy-4-methoxybenzophenone was isolated from the ethyl acetate fraction of Phaleria macrocarpa (Scheff.) Boerl. fruits. It was found to inhibit cell proliferation in HT-29 human colon carcinoma cell line but caused little damage to WRL-68 normal human liver and MRC-5 normal human fibroblast lung cell lines. The compound was found to sharply affect the viability of HT-29 cells in a dose- and time-dependent manner. HT-29 cells treated with the compound showed morphological changes under microscopic examination such as cell shrinkage, membrane blebbing, DNA fragmentation, and the occurrence of apoptotic nuclei. The percentage of early apoptotic, late apoptotic, and dead or necrotic cells was determined by flow cytometry using annexin V-FTIC/PI staining. In addition, flow cytometry showed that, when the HT-29 cells were treated with 115 µM of the compound, it resulted in G0/G1 phase arrest in a time-dependent manner. Western blot revealed an upregulation of PUMA, Bak, Bcl-2, and Mcl-1 proteins suggesting that the compound induced apoptosis in HT-29 cells by regulating these proteins.

  12. (2E,6E)-2,6-Bis(4-methyl­benzyl­idene)cyclo­hex-3-en-1-one

    PubMed Central

    Abaee, M. Saeed; Massa, Werner; Mojtahedi, Mohammad M.; Mesbah, A. Wahid

    2012-01-01

    The title compound, C22H20O, shows an approximately planar cyclo­hexenone ring [maximum deviation = 0.069 (4) Å], with a disordered position of the C=C bond [ratio = 0.71 (2)/0.29 (2)]. The benzene rings of the 4-methyl­benzyl­idene units, attached in the 2- and 6-positions to the cyclo­hexenone ring, are rotated in the same direction by 28.6 (4) and 22.4 (4)°, with respect to the mean plane of the cyclo­hexenone ring [fraction 0.71 (2); maximum deviation = 0.06 (3) Å]. In the crystal, mol­ecules are packed in the manner of a distorted hexa­gonal rod packing with their long axes all aligned along [201]. A number of C—H⋯π inter­actions stablize the crystal structure. PMID:22346982

  13. Synthesis and anti-inflammatory activity evaluation of some novel 6-alkoxy(phenoxy)-[1,2,4]triazolo[3,4-a]phthalazine-3-amine derivatives.

    PubMed

    Sun, Xian-Yu; Hu, Chuan; Deng, Xian-Qing; Wei, Cheng-Xi; Sun, Zhi-Gang; Quan, Zhe-Shan

    2010-11-01

    Starting from phthalic anhydride, several new 6-alkoxy(phenoxy)-[1,2,4]triazolo[3,4-a]phthalazine-3-amine derivatives were synthesized as potent anti-inflammatory agent. The study showed that the compounds 6h (6-(2-chlorophenoxy)-[1,2,4]triazolo[3,4-a]phthalazine-3-amine) and 6s (6-(4-aminophenoxy)-[1,2,4] triazolo[3,4-a]phthalazine-3-amine) exhibited the highest anti-inflammatory activity (81% and 83% inhibition, respectively, at 0.5 h after i.p. administration) which were slightly more potent than the reference drug Ibuprofen (61%). Furthermore, the peak activity of 6h and 6s was observed at the 3 h after p.o. administration, and they exhibited stronger anti-inflammatory activity than Ibuprofen at the dose of 50 mg/kg at the peak time.

  14. Design, Synthesis and Biological Evaluation of 6-(2,6-Dichloro-3,5-dimethoxyphenyl)-4-substituted-1H-indazoles as Potent Fibroblast Growth Factor Receptor Inhibitors.

    PubMed

    Zhang, Zhen; Zhao, Dongmei; Dai, Yang; Cheng, Maosheng; Geng, Meiyu; Shen, Jingkang; Ma, Yuchi; Ai, Jing; Xiong, Bing

    2016-10-23

    Tyrosine kinase fibroblast growth factor receptor (FGFR), which is aberrant in various cancer types, is a promising target for cancer therapy. Here we reported the design, synthesis, and biological evaluation of a new series of 6-(2,6-dichloro-3,5-dimethoxyphenyl)-4-substituted-1H-indazole derivatives as potent FGFR inhibitors. The compound 6-(2,6-dichloro-3,5-dimethoxyphenyl)-N-phenyl-1H-indazole-4-carboxamide (10a) was identified as a potent FGFR1 inhibitor, with good enzymatic inhibition. Further structure-based optimization revealed that 6-(2,6-dichloro-3,5-dimethoxyphenyl)-N-(3-(4-methylpiperazin-1-yl)phenyl)-1H-indazole-4-carboxamide (13a) is the most potent FGFR1 inhibitor in this series, with an enzyme inhibitory activity IC50 value of about 30.2 nM.

  15. Synthesis, antimicrobial activity and QSAR studies of new 2,3-disubstituted-3,3a,4,5,6,7-hexahydro-2H-indazoles.

    PubMed

    Minu, Maninder; Thangadurai, Ananda; Wakode, Sharad Ramesh; Agrawal, Shyam Sundar; Narasimhan, Balasubramanian

    2009-06-01

    Antimicrobial activity of synthesized 2,3-disubstituted-3,3a,4,5,6,7-hexahydro-2H-indazole derivatives indicated that 3-(4-chlorophenyl)-2-(4-nitrophenylsulfonyl)-3,3a,4,5,6,7-hexahydro-2H-indazole (6) and 3-(4-fluorophenyl)-2-(4-nitrophenylsulfonyl)-3,3a,4,5,6,7-hexahydro-2H-indazole (20) were the most active compounds. Further, the results of QSAR studies indicated the importance of topological parameters (2)chi and (2)chi(v) in defining the antimicrobial activity of hexahydroindazoles.

  16. 40 CFR 721.9527 - Bis(1,2,2,6,6-pentamethyl-4-piperidin-4-ol) ester of cy-clo-ali-phatic spiroketal.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-4-ol) ester of cy-clo-ali-phatic spiroketal. 721.9527 Section 721.9527 Protection of Environment...-piperidin-4-ol) ester of cy-clo-ali-phatic spiroketal. (a) Chemical substance and significant new uses...-piperidin-4-ol) ester of cycloaliphatic spiroketal (PMN No. P-91-1361) is subject to reporting under...

  17. 2-Amino-4-methyl-6-oxo-3,6-dihydro­pyrimidin-1-ium perchlorate–2-amino-6-methyl­pyrimidin-4(1H)-one–water (1/1/1)

    PubMed Central

    Kaabi, Kamel; El Glaoui, Maher; Ferretti, Valeria; Zeller, Matthias; Ben Nasr, Cherif

    2011-01-01

    In the title compound, C5H8N3O+·ClO4 −·C5H7N3O·H2O, each perchlorate anion is paired with a protonated cationic 2-amino-6-methyl­pyrimidin-4(1H)-one and another non-protonated entity of the same organic pyrimidinone. The crystal structure is stabilized by N—H⋯Oorg, N—H⋯Owater, N—H⋯OClO4, O—H⋯OClO4, N—H⋯N and C—H⋯OClO4 hydrogen bonds between the anions, organic entities and water mol­ecules. Inter­molecular π–π stacking inter­actions between neighbouring organic rings are observed with a face-to-face distance of 3.776 (2) Å, and O—H⋯O hydrogen bonds link the perchlorate anions and the water mol­ecules into chains along the b-axis direction. The perchlorate anion and the inter­stitial water mol­ecule are disordered over two mutually incompatible positions with a common occupancy ratio of 0.678 (16):0.322 (16). PMID:22065517

  18. 2-Amino-4-methyl-6-oxo-3,6-dihydro-pyrimidin-1-ium perchlorate-2-amino-6-methyl-pyrimidin-4(1H)-one-water (1/1/1).

    PubMed

    Kaabi, Kamel; El Glaoui, Maher; Ferretti, Valeria; Zeller, Matthias; Ben Nasr, Cherif

    2011-09-01

    In the title compound, C(5)H(8)N(3)O(+)·ClO(4) (-)·C(5)H(7)N(3)O·H(2)O, each perchlorate anion is paired with a protonated cationic 2-amino-6-methyl-pyrimidin-4(1H)-one and another non-protonated entity of the same organic pyrimidinone. The crystal structure is stabilized by N-H⋯O(org), N-H⋯O(water), N-H⋯O(ClO4), O-H⋯O(ClO4), N-H⋯N and C-H⋯O(ClO4) hydrogen bonds between the anions, organic entities and water mol-ecules. Inter-molecular π-π stacking inter-actions between neighbouring organic rings are observed with a face-to-face distance of 3.776 (2) Å, and O-H⋯O hydrogen bonds link the perchlorate anions and the water mol-ecules into chains along the b-axis direction. The perchlorate anion and the inter-stitial water mol-ecule are disordered over two mutually incompatible positions with a common occupancy ratio of 0.678 (16):0.322 (16).

  19. Dermal Sensitization Potential of Insect Repellents: Methyl N,N’-Dihexylethylenediaminemonocarbamate (CHR4), (E)-1,2,3,4-Tetrahydro-6-Methyl-1-(2-Methyl-1-Oxo-2-Butenyl) Quinoline (CHR5), and 1,2,3,4-Tetrahydro-6-Methyl-1-(3-Methyl-1-Oxo-2-Butenyl) Quinoline (CHR6).

    DTIC Science & Technology

    1984-05-20

    Chemical name: Methyl-N,N’-Dihexylethylenediamine- monocarbamate (CHR4) Chemical Abstract Service Registry No.: None Structural formula: CH3 (C11 2 )sNH...Quinoline (CRj5) Chemical Abstract Service Registry No.: None Structural formula: CH I C=O CH 3 ’CH 3 Empirical formula: C H NO- 3. Chemical Name...l,2,3,4-Tetralhydro-6-Me thyl-l-(3-Methiyi- l-Oxo-2-Sutenyl) Quinoline (CdiR6) Chemical Abstract Service Registry No.: None Ieia

  20. Silica gel-catalyzed one-pot syntheses in water and fluorescence properties studies of 5-amino-2-aryl-3H-chromeno[4,3,2-de][1,6]naphthyridine-4-carbonitriles and 5-amino-2-aryl-3H-quinolino[4,3,2-de][1,6]naphthyridine-4-carbonitriles.

    PubMed

    Wu, Hui; Lin, Wei; Wan, Yu; Xin, Hai-qiang; Shi, Da-qing; Shi, Yan-hui; Yuan, Rui; Bo, Rong-cheng; Yin, Wei

    2010-01-01

    The silica gel-catalyzed synthesis of 5-amino-2-aryl-3H-chromeno[4,3,2-de][1,6]naphthyridine-4-carbonitriles and 5-amino-2-aryl-3H-quinolino[4,3,2-de][1,6]naphthyridine-4-carbonitriles were simply achieved upon the one-pot cascade reaction of malononitrile with substituted 2-hydroxyacetophenone (or 2-aminoacetophenone) and aromatic aldehyde in aqueous media. The mechanistic investigation results based on electrospray ionization mass spectrometry (ESI-MS) indicated that malononitrile displayed a dual role during this transformation. Thirteen bonds were cleaved and 12 new bonds were constructed in the formation of 5-amino-2-aryl-3H-chromeno[4,3,2-de][1,6]naphthyridine-4-carbonitriles, while only 2 H(2)O molecules were removed. The fluorescence properties screening showed five new compounds have high fluorescence quantum yields.

  1. NCOA6 differentially regulates the expression of the CYP2C9 and CYP3A4 genes

    PubMed Central

    Surapureddi, Sailesh; Rana, Ritu; Goldstein, Joyce A

    2011-01-01

    CYP2Cs and CYP3A4 sub family of enzymes of the Cytochrome P-450 super family metabolize clinically prescribed therapeutics. Constitutive and induced expressions of these enzymes are under the control of HNF4α and rifampicin activated PXR. In the present study, we show a mechanism for ligand dependent synergistic cross talk between PXR and HNF4α. Two-hybrid screening identified NCOA6 as a HNF4α interacting protein. NCOA6 was also found to interact with PXR through the first LXXLL motif in GST pull down and mammalian two hybrid assays. NCOA6 enhances the synergistic activation of CYP2C9 and CYP3A4 promoter activity by PXR and HNF4α in the presence of rifampicin. However silencing NCOA6 abrogated the synergistic activation and induction of CYP2C9 by PXR-HNF4α but not of CYP3A4. ChIP analysis revealed that NCOA6 could bridge HNF4α and PXR binding sites of the CYP2C9 promoter. Our results indicate that NCOA6 is responsible for the synergistic activation of CYP2C9 by HNF4α and PXR and NCOA6 differentially regulates CYP2C9 and CYP3A4 gene expression though both the genes are regulated by the same nuclear receptors. PMID:21292004

  2. Chronic toxicity of 2,4,6-trinitrotoluene to a marine polychaete and an estuarine amphipod

    SciTech Connect

    Green, A.; Moore, D.; Farrar, D.

    1999-08-01

    The chronic toxicity of sediment-associated 2,4,6-trinitrotoluene (TNT) to the marine polychaete Neanthes arenaceodentata and the estuarine amphipod Leptocheirus plumulosus was evaluated. Test organisms were exposed to sediments spiked with radiolabeled TNT for 28 d, after which time the endpoints of mortality, growth, and reproduction (L. plumulosus only) were assayed and compared against the TNT tissue concentrations as well as the TNT sediment concentrations. Survival was significantly reduced at a tissue concentration of 61 {micro}g TNT/g wet wt tissue in N. arenaceodentata and L. plumulosus with enhancement (significant for N. arenaceodentata) occurring at the lower TNT concentrations. Growth was significantly reduced at the highest TNT exposure of 10.0 {micro}g TNT/g wet wt tissue in L. plumulosus. Reproduction was significantly reduced at a tissue concentration of 6.3 {micro}g TNT/g wet wt tissue in L. plumulosus. The results of this study demonstrate that both N. arenaceodentata and L. plumulosus are sensitive to the presence of sediment-associated TNT and that more information is needed about the toxicity of TNT to benthic fauna to facilitate risk assessment and management of TNT-contaminated sites.

  3. SEDIMENT-MEDIATED REDUCTION OF 2,4,6-TRINITROTOLUENE AND FATE OF THE RESULTING AROMATIC (POLY)AMINES

    EPA Science Inventory

    2,4,6-Trinitrotoluene is a major surface and subsurface contaminant found at numerous munitions production and storage facilities. The reductive transformation of 2,4,6-trinitrotoluene (TNT) to aromatic (poly)amines and the consequent fate of these products were studied in anaer...

  4. Colorimetric determination of 1-(4'-nitrophenyl)-2-aminopropane-1,3-diol with 2,4,6-trinitrobenzenesulfonic acid in the presence of chloramphenicol.

    PubMed

    Pietta, P G; Agnellini, D; Pace, M

    1979-12-01

    A colorimetric method based on the interaction between the chloramphenicol degradation product 1-(4'-nitrophenyl)-2-aminopropane-1,3-diol and the 2,4,6-trinitrobenzenesulfonic acid reagent was developed. Analytical solutions were reacted with the reagent at pH 9.1 for 20 min at room temperature, and the resulting color was measured at 340 nm. A linear relationship between absorbance and concentration occurred within the 5--25-micrograms/ml range under the conditions studied. Replicate analyses were in good agreement. An average recovery of 99.4 +/- 0.4% was obtained for the synthetic mixtures.

  5. The 1-((diorganooxy phosphonyl) methyl)-2,4- and -2,6-diamino benzenes and their derivatives

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, John A. (Inventor); Kourtides, Demetrius A. (Inventor)

    1987-01-01

    The 1-((diorganooxy phosphonyl) methyl)-2,4- and -2,6-dinitro- and diamino benzenes are prepared by nitrating an (organo phosphenyl) methyl benzene to produce the dinitro compounds which are then reduced to the diamino compounds. The organo groups (alkyl, haloalkyl, aryl) on the phosphorus may be removed to give the free acids (HO)2P(=0)-. The diamino compounds may be polymerized with dianhydrides or diacyl halides to produce fire and flame resistant polymers which are useful in the manufacture of aircraft structures.

  6. 6-Methyl-1,2,4-benzenetriol, a new intermediate in penicillic acid biosynthesis in Penicillium cyclopium

    SciTech Connect

    Sekiguchi, J.; Katayama, S.; Yamada, Y.

    1987-07-01

    Penicillic acid-negative mutants were obtained from a color mutant derived from Penicillium cyclopium NRRL 1888 through N-methyl-N'-nitro-N-nitrosoguanidine treatment. One mutant (SK2N6) accumulated 6-methyl-1,2,4-benzenetriol, which was not previously known to be a metabolite of P. cyclopium, in addition to orsellinic acid and orcinol. The radioactivity of (1-/sup 14/C)acetic acid was rapidly incorporated into 6-methyl-1,2,4-benzenetriol in a culture of P. cyclopium SK2N6. Moreover, the radioactivity of (/sup 14/C)6-methyl-1,2,4-benzenetriol was efficiently incorporated into penicillic acid in a culture of P. cyclopium NRRL 1888. These data indicate that 6-methyl-1,2,4-benzenetriol is a precursor for penicillic acid biosynthesis. The results on the addition of 1,4-dihydroxy-6-methoxy-2-methylbenzene, 6-methoxy-2-methylbenzoquinone (1,4), and 1-O-methylorcinol to a culture of P. cyclopium SK2N6 indicated that only the former two compounds are converted to penicillic acid. Thus, a new portion of the penicillic acid biosynthetic pathway is proposed.

  7. Exploring the thermoelectric and magnetic properties of uranium selenides: Tl2Ag2USe4 and Tl3Cu4USe6

    NASA Astrophysics Data System (ADS)

    Azam, Sikander; Khan, Saleem Ayaz; Din, Haleem Ud; Khenata, Rabah; Goumri-Said, Souraya

    2016-09-01

    The electronic, magnetic and thermoelectric properties of Tl2Ag2USe4 and Tl3Cu4USe6 compounds were investigated using the full potential linear augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). The exchange correlation was treated with the generalized gradient approximation plus optimized effective Hubbard parameter and spin-orbit coupling (GGA+U+SOC). The present uranium selenides show narrow direct energy band gap values of 0.7 and 0.875 eV for Tl2Ag2USe4 and Tl3Cu4USe6 respectively. For both selenides U-d/f states are responsible for electrical transport properties. Uranium atoms were the most contributors in the magnetic moment compared to other atoms and show ferromagnetic nature. The spin density isosurfaces show the polarization of neighboring atoms of Uranium, such as silver/copper and selenium. Thermoelectric calculations reveal that Tl3Cu4USe6 is more suitable for thermoelectric device applications than Tl2Ag2USe4.

  8. Transformation of 2,4,6-trinitrotoluene by the aquatic plant Myriophyllum spicatum

    SciTech Connect

    Pavlostathis, S.G.; Comstock, K.K.; Jacobson, M.E.; Saunders, F.M.

    1998-11-01

    The ability of the aquatic plant Eurasian Watermilfoil (Myriophyllum spicatum) to transform 2,4,6-trinitrotoluene (TNT) was investigated in a series of batch assays. The TNT was added to plant cultures in single and multiple consecutive additions, at various initial concentrations, to determine its transformation kinetics, identify products formed, evaluate phytotoxic effects, and to determine the effect of light deprivation on the TNT transformation process. Rapid disappearance of TNT from the plant culture media was observed. The TNT disappearance rate was a function of both plant and TNT concentration (i.e., followed mixed, second-order kinetics). The TNT transformation occurred only in the presence of plants and was inhibited by the addition of sodium azide. Phytotoxicity leading to plant chlorosis was observed in batch plant cultures with an initial TNT concentration above 5.9 {micro}M. Reductive transformation of TNT to aminodinitrotoluenes and lower levels of hydroxylaminodinitrotoluene and diaminonitrotoluenes detected in the plant culture media accounted for less than 10 to 20% of the total TNT mass added. Extraction of plant material at the end of batch incubations when all TNT was depleted from the media yielded low levels of TNT and aminodinitrotoluenes and accounted for only 3.4% of the initially added TNT mass. Light deprivation decreased both the rate and extent of the reductive transformation of TNT.

  9. Mitochondria targeted peptides protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxicity.

    PubMed

    Yang, Lichuan; Zhao, Kesheng; Calingasan, Noel Y; Luo, Guoxiong; Szeto, Hazel H; Beal, M Flint

    2009-09-01

    A large body of evidence suggests that mitochondrial dysfunction and oxidative damage play a role in the pathogenesis of Parkinson's disease (PD). A number of antioxidants have been effective in animal models of PD. We have developed a family of mitochondria-targeted peptides that can protect against mitochondrial swelling and apoptosis (SS peptides). In this study, we examined the ability of two peptides, SS-31 and SS-20, to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity in mice. SS-31 produced dose-dependent complete protection against loss of dopamine and its metabolites in striatum, as well as loss of tyrosine hydroxylase immunoreactive neurons in substantia nigra pars compacta. SS-20, which does not possess intrinsic ability in scavenging reactive oxygen species, also demonstrated significant neuroprotective effects on dopaminergic neurons of MPTP-treated mice. Both SS-31 and SS-20 were very potent (nM) in preventing MPP+ (1-methyl-4-phenylpyridinium)-induced cell death in cultured dopamine cells (SN4741). Studies with isolated mitochondria showed that both SS-31 and SS-20 prevented MPP+-induced inhibition of oxygen consumption and ATP production, and mitochondrial swelling. These findings provide strong evidence that these neuroprotective peptides, which target both mitochondrial dysfunction and oxidative damage, are a promising approach for the treatment of PD.

  10. Mitochondria Targeted Peptides Protect Against 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine Neurotoxicity

    PubMed Central

    Yang, Lichuan; Zhao, Kesheng; Calingasan, Noel Y.; Luo, Guoxiong; Szeto, Hazel H.

    2009-01-01

    Abstract A large body of evidence suggests that mitochondrial dysfunction and oxidative damage play a role in the pathogenesis of Parkinson's disease (PD). A number of antioxidants have been effective in animal models of PD. We have developed a family of mitochondria-targeted peptides that can protect against mitochondrial swelling and apoptosis (SS peptides). In this study, we examined the ability of two peptides, SS-31 and SS-20, to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity in mice. SS-31 produced dose-dependent complete protection against loss of dopamine and its metabolites in striatum, as well as loss of tyrosine hydroxylase immunoreactive neurons in substantia nigra pars compacta. SS-20, which does not possess intrinsic ability in scavenging reactive oxygen species, also demonstrated significant neuroprotective effects on dopaminergic neurons of MPTP-treated mice. Both SS-31 and SS-20 were very potent (nM) in preventing MPP+ (1-methyl-4-phenylpyridinium)-induced cell death in cultured dopamine cells (SN4741). Studies with isolated mitochondria showed that both SS-31 and SS-20 prevented MPP+-induced inhibition of oxygen consumption and ATP production, and mitochondrial swelling. These findings provide strong evidence that these neuroprotective peptides, which target both mitochondrial dysfunction and oxidative damage, are a promising approach for the treatment of PD. Antioxid. Redox Signal. 11, 2095–2104. PMID:19203217

  11. Magnetic and structural transitions in La0.4Na0.6Fe2As2 single crystals

    DOE PAGES

    Yan, Jiaqiang; Nandi, S.; Saparov, Bayrammurad I.; ...

    2015-01-05

    La0.4Na0.6Fe2As2 single crystals have been grown out of an NaAs flux in an alumina crucible and characterized by measuring magnetic susceptibility, electrical resistivity, specific heat, as well as single-crystal x-ray and neutron diffraction. La0.4Na0.6Fe2As2 single crystals show a structural phase transition from a high-temperature tetragonal phase to a low-temperature orthorhombic phase at Ts=125 K. This structural transition is accompanied by an anomaly in the temperature dependence of electrical resistivity, anisotropic magnetic susceptibility, and specific heat. Concomitant with the structural phase transition, the Fe moments order along the a direction with an ordered moment of 0.7(1) μB at T=5 K. Finally,more » the low-temperature stripe antiferromagnetic structure is the same as that in other AFe2As2 (A = Ca, Sr, Ba) compounds. La0.5₋xNa0.5+xFe2As2 provides a material platform for the study of iron-based superconductors where the electron-hole asymmetry could be studied by simply varying the La/Na ratio.« less

  12. Bis(2,3-diamino­pyridinium) bis­(μ-pyridine-2,6-dicarboxyl­ato)-κ4 O 2,N,O 6:O 64 O 2:O 2,N,O 6-bis­[aqua­(pyridine-2,6-dicarboxyl­ato-κ3 O 2,N,O 6)bis­muthate(III)] tetra­hydrate

    PubMed Central

    Aghabozorg, Hossein; Kazemi, Shokoofeh; Agah, Ali Akbar; Mirzaei, Masoud; Notash, Behrouz

    2011-01-01

    In the centrosymmetric dinuclear complex anion of the title compound, (C5H8N3)2[Bi2(C7H3NO4)4(H2O)24H2O, the BiIII atom is eight-coordinated in an N2O6 environment and has a distorted bicapped trigonal–prismatic coordination environment. Extensive inter­molecular O—H⋯O, N—H⋯O and weak C—H⋯O hydrogen bonds lead to the stability of the crystal structure. Inter­actions between one C—H group of the 2,3-diamino­pyridinium [(2,3-dapyH)+] cation and the aromatic ring of the pyridine-2,6-dicarboxyl­ate (pydc) ligand (C—H⋯centroid distance = 2.78 Å) and π–π inter­actions between the (2,3-dapyH)+ cations and between the (2,3-dapyH)+ cation and the pydc ligand [centroid–centroid distances = 3.489 (5) and 3.694 (5) Å] are observed. PMID:21522286

  13. 40 CFR 721.4589 - Propanedioic acid, [(4-methoxyphenyl)methylene]-, bis(1,2,2,6,6-pentamethyl-4-piperdinyl) ester...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-pentamethyl-4-piperdinyl) ester (9CI). 721.4589 Section 721.4589 Protection of Environment ENVIRONMENTAL...-pentamethyl-4-piperdinyl) ester (9CI). (a) Chemical substance and significant new uses subject to reporting...) ester (9CI) (PMN P-95-1411; CAS No. 147783-69-5) is subject to reporting under this section for...

  14. 40 CFR 721.4589 - Propanedioic acid, [(4-methoxyphenyl)methylene]-, bis(1,2,2,6,6-pentamethyl-4-piperdinyl) ester...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-pentamethyl-4-piperdinyl) ester (9CI). 721.4589 Section 721.4589 Protection of Environment ENVIRONMENTAL...-pentamethyl-4-piperdinyl) ester (9CI). (a) Chemical substance and significant new uses subject to reporting...) ester (9CI) (PMN P-95-1411; CAS No. 147783-69-5) is subject to reporting under this section for...

  15. Synthesis of 4‧-substituted-2,2‧;6‧,2″-terpyridine Ru(II) complexes electrochemical, fluorescence quenching and antibacterial studies

    NASA Astrophysics Data System (ADS)

    Ezhilarasu, Tamilarasu; Sathiyaseelan, Anbazhagan; Kalaichelvan, Pudupalayam Thangavelu; Balasubramanian, Sengottuvelan

    2017-04-01

    Three new Ru(II) terpyridine complexes viz. [Ru(BBtpy)2](PF6)2 [Ru(L1)] (BBtpy = 4‧-(4-benzyloxybenzaldehyde)-2,2‧:6‧,2″-terpyridine), [Ru(BMBtpy)2](PF6)2 [Ru(L2)] (BMBtpy = 4‧-(4-benzyloxy-3-methoxybenzaldehyde)-2,2‧:6‧,2″-terpyridine) and [Ru(BEBtpy)2](PF6)2 [Ru(L3)] (BEBtpy = 4‧-(4-benzyloxy-3-ethoxybenzaldehyde)-2,2‧:6‧,2″-terpyridine) have been synthesized and characterized. The MALDI-TOF/MS fragmentation pattern of [Ru(BMBtpy)2](PF6)2 complex exhibits a molecular ion peak at m/z = 987.09 [M-2PF6]2+ fragment. These Ru(II) complexes are redox active, show both metal centered oxidation and ligand centered reduction processes. The peak potential and peak current Ipa and Ipc also undergo definite shift and increase with increase in the scan rate (20-120 mV/s). The fluorescence of Ru(II) complexes [Ru(L1)], [Ru(L2)] and [Ru(L3)] are effectively quenched by 1,4-benzoquinone and 1,4-naphthoquinone in acetonitrile. The antibacterial activity of ruthenium(II) complexes were screened against four human pathogens both gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and gram negative bacteria (Escherichia coli, Klebsiella pneumonia) by the well diffusion method. The antibacterial activity of Ru(II) complexes is comparable to that of standard antibiotics like tetracycline.

  16. Isolation and structures of sulfonium salts derived from thioethers: [{o-C(6)H(4)(CH(2)SMe)(2)}H][NbF(6)] and [{[9]aneS(3)}H][NbF(6)].

    PubMed

    Jura, Marek; Levason, William; Reid, Gillian; Webster, Michael

    2009-10-07

    Two very unusual sulfonium salts, [{o-C(6)H(4)(CH(2)SMe)(2)}H][NbF(6)] and [{[9]aneS(3)}H][NbF(6)], obtained from reaction of the thioethers with NbF(5) in CH(2)Cl(2) solution, are reported and their structures described; the eight-coordinate tetrafluoro Nb(v) cation of the dithioether is obtained from the same reaction.

  17. LASERS: Tunable lasing due to the 4T2-4A2 electronic-vibrational transition in Cr3+ ions in BeAl6O10

    NASA Astrophysics Data System (ADS)

    Alimpiev, A. I.; Pestryakov, Efim V.; Petrov, V. V.; Solntsev, V. P.; Trunov, V. I.; Matrosov, V. N.

    1988-03-01

    Tunable radiation in the 0.79-0.87 μm range was obtained at room temperature in a new active medium BeAl6O10:Cr3+. The energy gap between the 2E and 4T2 levels (~ 236 cm-1) and the activation energy Ea approx 1667 cm-1 were determined. Absorption, luminescence, and excitation spectra were determined and an investigation was made of the temperature dependence of the excited-state relaxation time of Cr3+ ions in BeAl6O10(τlum approx 13 × 10-6 s at 300 K).

  18. (4′-Ethynyl-2,2′:6′,2′′-terpyridine)(2,2′:6′,2′′-terpyridine)­ruthenium(II) bis­(hexa­fluoridophosphate) acetonitrile disolvate

    PubMed Central

    Chen, Weizhong; Rein, Francisca N.; Scott, Brian L.; Rocha, Reginaldo C.

    2013-01-01

    The title heteroleptic bis­-terpyridine complex, [Ru(C15H11N3)(C17H11N3)](PF6)2·2CH3CN, crystallized from an acetonitrile solution as a salt containing two hexa­fluoridophosphate counter-ions and two acetonitrile solvent mol­ecules. The RuII atom has a distorted octa­hedral geometry due to the restricted bite angle [157.7 (3)°] of the two mer-arranged N,N′,N′′-tridendate ligands, viz. 2,2′:6′,2′′-terpyridine (tpy) and 4′-ethynyl-2,2′:6′,2′′-terpyridine (tpy′), which are essentially perpendicular to each other, with a dihedral angle of 87.75 (12)° between their terpyridyl planes. The rod-like acetyl­ene group lies in the same plane as its adjacent terpyridyl moiety, with a maximum deviation of only 0.071 (11) Å from coplanarity with the pyridine rings. The mean Ru—N bond length involving the outer N atoms trans to each other is 2.069 (6) Å at tpy and 2.070 (6) Å at tpy′. The Ru—N bond length involving the central N atom is 1.964 (6) Å at tpy and 1.967 (6) Å at tpy′. Two of the three counter anions were refined as half-occupied. PMID:23424425

  19. Microcrystalline phase transformation from ZrF4·HF·2H2O to ZrO2 through the intermediate phases ZrF4·3H2O, ZrF4·H2O, Zr2OF6·H2O and ZrF4

    NASA Astrophysics Data System (ADS)

    Dey, C. C.

    2014-09-01

    The behavior of hydrated zirconium fluoride has been studied by perturbed angular correlation spectroscopy. It is found that the crystalline compound ZrF4·HF·2H2O, formed initially by drying solution of Zr metal in concentrated HF, transforms spontaneously to ZrF4·3H2O. This trihydrated compound dehydrates to ZrF4 through the intermediate monohydrates ZrF4·H2O and Zr2OF6·H2O. The compound ZrF4 finally transforms to ZrO2 at ∼343 K. Different crystalline phases of ZrF4·HF·2H2O, ZrF4·3H2O, ZrF4·H2O, Zr2OF6·H2O, ZrF4 and ZrO2 have been identified and characterized by PAC spectroscopy. From previous PAC measurements, the intermediate ZrF4·H2O and Zr2OF6·H2O were not observed and the dehydration from ZrF4·3H2O to ZrF4 was found to be routed directly. Present measurements by PAC exhibits dissimilar crystal structures for ZrF4·3H2O and ZrF4·H2O unlike the crystal structures found in hafnium analogous compounds.

  20. RE2MAl6Si4 (RE = Gd, Tb, Dy; M = Au, Pt): layered quaternary intermetallics featuring CaAl2Si2-type and YNiAl4Ge2-type slabs grown from aluminum flux.

    PubMed

    Latturner, Susan E; Bilc, Daniel; Mahanti, S D; Kanatzidis, Mercouri G

    2003-12-01

    Six new intermetallic aluminum silicides--Gd(2)PtAl(6)Si(4), Gd(2)AuAl(6)Si(4), Tb(2)PtAl(6)Si(4), Tb(2)AuAl(6)Si(4), Dy(2)PtAl(6)Si(4), and Dy(2)AuAl(6)Si(4)--have been obtained from reactions carried out in aluminum flux. The structure of these compounds was determined by single-crystal X-ray diffraction. They form in space group Rthremacr;m with cell constants of a = 4.1623(3) A and c = 51.048(5) A for the Gd(2)PtAl(6)Si(4) compound. The crystal structure is comprised of hexagonal nets of rare earth atoms alternating with two kinds of layers that have been observed in other multinary aluminide intermetallic compounds (CaAl(2)Si(2) and YNiAl(4)Ge(2)). All six RE(2)MAl(6)Si(4) compounds show antiferromagnetic transitions at low temperatures (T(N) < 20 K); magnetization studies of the Dy compounds show metamagnetic behavior with reorientation of spins at 6000 G. Band structure calculations indicate that the AlSi puckered hexagonal sheets in this structure are electronically distinct from the other surrounding structural motifs.

  1. IR, FT-ICR-MS studies on (1'S, 6'S)-1-cyclopropyl-7-(2,8-diazabicyclo[4.3.0] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid hydrochloride salt.

    PubMed

    Lin, Zhiwei

    2014-01-01

    The infrared spectra of (1'S, 6'S)-1-cyclopropyl-7-(2,8-diazabicyclo[4.3.0] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid hydrochloride salt (CLF-HCl) were studied and compared with free base. Their fragmentation pathways were investigated using tandem mass spectrometric (MS/MS) techniques on Fourier-transform ion cyclotron resonance spectrum, and many characteristic fragment ions were found.

  2. Systematic study of spin crossover and structure in [Co(terpyRX)2](Y)2 systems (terpyRX = 4'-alkoxy-2,2':6',2''-terpyridine, X = 4, 8, 12, Y = BF4(-), ClO4(-), PF6(-), BPh4(-)).

    PubMed

    Nielsen, Pia; Toftlund, Hans; Bond, Andrew D; Boas, John F; Pilbrow, John R; Hanson, Graeme R; Noble, Christopher; Riley, Mark J; Neville, Suzanne M; Moubaraki, Boujemaa; Murray, Keith S

    2009-08-03

    A family of spin crossover cobalt(II) complexes of the type [Co(terpyRX)(2)](Y)(2) x nH(2)O (X = 4, 8, 12 and Y = BF(4)(-), ClO(4)(-), PF(6)(-), BPh(4)(-)) has been synthesized, whereby the alkyl chain length, RX, and counteranion, Y, have been systematically varied. The structural (single crystal X-ray diffraction) and electronic (magnetic susceptibility, electron paramagnetic resonance (EPR)) properties have been investigated within this family of compounds. Single crystal X-ray diffraction analysis of [Co(terpyR8)(2)](ClO(4))(2), [Co(terpyR8)(2)](BF(4))(2) x H(2)O, and [Co(terpyR4)(2)](PF(6))(2) x 3 H(2)O, at 123 K, revealed compressed octahedral low spin Co(II) environments and showed varying extents of disorder in the alkyl tail portions of the terpyRX ligands. The magnetic and EPR studies were focused on the BF(4)(-) family and, for polycrystalline solid samples, revealed that the spin transition onset temperature (from low to high spin) decreased as the alkyl chain lengthened. EPR studies of polycrystalline powder samples confirmed these results, showing signals only due to the low spin state at the temperatures seen in magnetic measurements. Further to this, simultaneous simulation of the EPR spectra of frozen solutions of [Co(terpyR8)(2)](BF(4))(2) x H(2)O, recorded at S-, X-, and Q-band frequencies, allowed accurate determination of the g and A values of the low spin ground state. The temperature dependence of the polycrystalline powder EPR spectra of this and the R4 and R12 complexes is explained in terms of Jahn-Teller effects using the warped Mexican hat potential energy surface model perturbed by the low symmetry of the ligands. While well recognized in Cu(II) systems, this is one of the few times this approach has been used for Co(II).

  3. New estimates of global CH4 and C2H6 production in the Precambrian crust

    NASA Astrophysics Data System (ADS)

    Sutcliffe, Chelsea N.; Lacrampe-Couloume, Georges; Ballentine, Chris J.; Sherwood Lollar, Barbara

    2015-04-01

    Saline fracture fluids found deep within the Precambrian shield possess isotopic and geochemical signatures consistent with prolonged water rock interaction. Noble gas-derived residence times of these fluids, on the order of millions to billions of years, highlight their significance as an ancient deep hydrosphere (Lippmann-Pipke et al., 2011; Holland et al., 2013). With mM concentrations of dissolved gases such as H2 and hydrocarbons, these fracture fluids are energy rich and capable of sustaining microbial communities of H2-utilizing methanogens and sulphate reducers (Lin et al., 2006). Globally, Precambrian rocks constitute over 70% of the volume of the continental crust (Goodwin, 1996) and represent a substantial under-investigated source of such dissolved gases. Recent calculations of global H2 production from these Precambrian Shield rocks, including both hydration reactions and radiolysis, doubles previous estimates to an increased rate of 0.4-2.3 x 1011 mol/yr (Sherwood Lollar et al., 2014). This has important consequences for hydrocarbon production, reflected in the high abundance of CH4 and C2H6 in dissolved fracture gases, up to 80 and 10 vol %, respectively. Given the long residence times of these fluids, hydrocarbon production could have persisted on geological timescales. To date, production from this source has not been incorporated into models of evolution of the early atmosphere. Additionally, the quantification of abiotic sources of methane and ethane in the analogous terrestrial Precambrian crust could contribute to our understanding of the origin of the episodic traces of methane recently detected on Mars (Webster et al., 2014). Investigating the origin of these gases has important implications for the global carbon cycle, as well as the distribution of life in the terrestrial deep subsurface and on other planets. We examine the isotopic evolution of these fracture fluids in the Canadian Shield and provide the first attempts to estimate methane

  4. Degradation of 2,4,6-trichlorophenol by bacteria isolated from secondary sludge of a pulp and paper mill.

    PubMed

    Karn, Santosh Kr; Reddy, M Sudhakara

    2012-01-01

    Bacterial strains capable of degrading trichlorophenol (2,4,6-TCP) were isolated from the secondary sludge of a pulp and paper mill and were characterized. These isolates were identified as Planococcus rifietoensis (CL4) and Bacillus pumilus (CL5), based on their 16S rRNA sequence analysis. These isolates were able to grow and utilize 2,4,6-TCP as their source of carbon as well as energy. HPLC analysis and stoichometric release of chloride in the medium confirmed the degradation ability of these isolates. Removal efficiency of 2,4,6-TCP by these isolates was discovered to be high. They were able to remove 90% of 2,4,6-TCP when grown at a concentration of 600 mg L(-1). Inoculation of these bacteria completely removed 2,4,6-TCP within 2 weeks from the sludge of the pulp and paper mill when supplemented at the rate of 100 mg L(-1). Absorbable Organic Halogen (AOX) and Extractable Organic Halogen (EOX) were significantly reduced by 63% and 70% respectively from the sludge due to inoculation of these bacteria. These isolates have high potential to remove 2,4,6-TCP and may be used for removal of 2,4,6-TCP from pulp paper mill waste.

  5. Research program and teaching led by the master in Hippocrates' Epidemics 2, 4 and 6.

    PubMed

    Alessi, Robert

    2010-01-01

    This paper addresses the extent to which one may identify in the author of Epidemics 2, 4 and 6 the personality of a master who shared - and probably led--with several colleagues a research program focused on a few topics which were both used for teaching purposes. The first lines of Epidemics 2.3.1 (the so-called katastasis of Perinthus), are the starting-point of the analysis, where information is given about the arrival in Perinthus of a community of doctors, probably composed by masters and disciples. Further commenting on this difficult passage (where a new establishment ot the text is proposed) in connection with others shows the author either expressing his disagreement with colleagues, or making recommendations to pupils, by words which denote a particularly strong and distinguished personality whose purpose is not to give to the reader a complete description of diseases and symptoms for his observations were in fact determined by precise research considerations. Medical research is in fact, in this group of doctors and pupils arriving in Perinthus where the personality of the author prevails, closely related to the needs of teaching.

  6. 40 CFR 721.9527 - Bis(1,2,2,6,6-pentamethyl-4-piperidin-4-ol) ester of cy-clo-ali-phatic spiroketal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... processing/use workers only, requirements as specified in § 721.63(a)(4), (a)(5)(iv), (a)(5)(v), (a)(5)(vi... paragraph: This substance may cause systemic effects, eye irritation. (iii) Industrial, commercial,...

  7. Synthesis of 2,6-trans- and 3,3,6-trisubstituted tetrahydropyran-4-ones from Maitland-Japp derived 2H-dihydropyran-4-ones: a total synthesis of diospongin B.

    PubMed

    Clarke, Paul A; Nasir, Nadiah Mad; Sellars, Philip B; Peter, Alejandra M; Lawson, Connor A; Burroughs, James L

    2016-07-12

    6-Substituted-2H-dihydropyran-4-one products of the Maitland-Japp reaction have been converted into tetrahydropyrans containing uncommon substitution patterns. Treatment of 6-substituted-2H-dihydropyran-4-ones with carbon nucleophiles led to the formation of tetrahydropyran rings with the 2,6-trans-stereochemical arrangement. Reaction of the same 6-substituted-2H-dihydropyran-4-ones with l-Selectride led to the formation of 3,6-disubstituted tetrahydropyran rings, while trapping of the intermediate enolate with carbon electrophiles in turn led to the formation 3,3,6-trisubstituted tetrahydropyran rings. The relative stereochemical configuration of the new substituents was controlled by the stereoelectronic preference for pseudo-axial addition of the nucleophile and trapping of the enolate from the opposite face. Application of these methods led to a synthesis of the potent anti-osteoporotic diarylheptanoid natural product diospongin B.

  8. A bimetallic iridium(ii) catalyst: [{Ir(IDipp)(H)}2][BF4]2 (IDipp = 1,3-bis(2,6-diisopropylphenylimidazol-2-ylidene)).

    PubMed

    Rubio-Pérez, Laura; Iglesias, Manuel; Munárriz, Julen; Polo, Victor; Sanz Miguel, Pablo J; Pérez-Torrente, Jesús J; Oro, Luis A

    2015-06-18

    A new Ir(ii) complex [{Ir(μ-κCNHC,η(6)Dipp-IDipp)(H)}2][BF4]2 has been prepared and fully characterised. This complex acts as a catalyst for the hydroalkynylation of imines according to an unprecedented diiridium-mediated mechanism.

  9. Synthesis of N-unsubstituted and N-methyl derivatives of 4-aryl-2,6-dimethyl-1,2-dihydropyridine-3,5-dicarbonitriles

    SciTech Connect

    Zandersons, A.Z.; Lusis, V.K.; Mutsenietse, D.Kh.; Dubur, G.Ya.

    1987-07-01

    In the reduction of 2,6-dimethyl-4-arylpyridine-3,5-dicarbonitriles or their N-oxides by sodium borohydride, a mixture of 1,2- and 1,4-dihydropyridine-3,5-dicarbonitriles is formed. 1,2,6-Trimethyl-4-aryl-1,2-dihydropyridine-3,5-dicarbonitriles were obtained by reducing the corresponding pyridinium perchlorates or by alkylating 4-acryl-2,6-dimethyl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives by methyl iodide.

  10. 4',6-diamidino-2-phenylindole (DAPI) interacts with rare structures of GC polymers.

    PubMed

    Barcellona, M L; Chen, Y; Müller, J D; Gratton, E

    2001-01-01

    The binding of 4',6-diamidino-2-phenylindole (DAPI) to double-stranded GC polymers either in the alternating or in homopolymer sequence was investigated using fluorescence techniques. We employed fluctuation correlation spectroscopy, which measures the diffusion coefficient of fluorescent particles, to demonstrate that the fluorescence was originating from relatively slowly diffusing entities. These entities display a very large heterogeneity of diffusing coefficients, indicating that molecular aggregation is extensive in our samples. We used frequency domain fluorometry to characterize the fluorescence lifetime of the species, while varying the GC polymer-dye coverage systematically. At very low coverage we observed a relatively bright fluorescent component with a lifetime value of approximately 4 ns. The stoichiometry of binding of this bright species was such that it can only arise from rare molecular structures, either unusual loops or large molecular aggregates. The amount and characteristics of this bright fluorescent component were different between the homo and the alternating polymer, indicating that the difference in sequence of the two polymers is responsible for the different aggregates which are then detected in the fluorescence experiment. At large GC polymer coverage we observed a relatively wide distribution of fluorescent species with short lifetime values, in the range between 0.12 and 0.2 ns. Given the stoichiometry of binding of this fluorescent component, we concluded that it could arise either from intercalative and/or non-specific binding to the DNA double-stranded molecules. We comment on the origin of the rare but brightly fluorescent binding sites and discuss the potential to detect such unusual DNA structures.

  11. Mechanistic aspects of 4-amino-2,6-dichlorophenol-induced in vitro nephrotoxicity.

    PubMed

    Rankin, Gary O; Hong, Suk-Kil; Anestis, Dianne K; Ball, John G; Valentovic, Monica A

    2008-03-12

    4-Amino-2,6-dichlorophenol (ADCP) is a potent acute nephrotoxicant in vivo inducing prominent renal corticomedullary necrosis. In vitro, ADCP exposure increases lactate dehydrogenase (LDH) release from rat renal cortical slices at 0.05 mM or greater. The purpose of this study was to examine the ability of antioxidants, cytochrome P450 (CYP) and flavin adenine dinucleotide monooxygenase (FMO) activity modulators, indomethacin, glutathione and inhibitors of glutathione conjugate metabolism to attenuate ADCP cytotoxicity in vitro. Renal cortical slices prepared from untreated male Fischer 344 rats (N=4/group) were preincubated at 37 degrees C under a 100% oxygen atmosphere with an inhibitor or vehicle for 5-30 min. ADCP (0.05-0.5mM) or vehicle was added and incubations continued for 120 min. At the end of the incubation period, LDH release was measured as an index of nephrotoxicity. ADCP cytotoxicity was partially attenuated by ascorbate (1.0 or 2.0mM), but not by N,N'-diphenyl-p-phenylenediamine (DPPD), alpha-tocopherol or deferoxamine. Inhibitors of CYP (metyrapone, piperonyl butoxide and isoniazid) and FMO activity modulators (methimazole, N-octylamine) had no effect on ADCP cytotoxicity. Indomethacin or glutathione 1.0mM completely and partially blocked ADCP 0.1 and 0.5mM cytotoxicity, respectively. N-acetylcysteine, AOAA (an inhibitor of cysteine conjugate beta-lyase) and probenecid (an organic anion transport inhibitor), but not AT-125 (an inhibitor of gamma-glutamyl transferase), partially attenuated ADCP 0.1mM cytotoxicity. Overall, these results suggest that reactive metabolites may be produced from ADCP primarily via a co-oxidation-mediated mechanism. The difference in the ability of ascorbate and glutathione to attenuate ADCP-induced cytotoxicity in vitro in kidney cells could indicate that alkylation via the reactive benzoquinoneimine metabolite might be responsible for cytotoxicity rather than a free radical-mediated mechanism.

  12. Measuring Ca2+-signalling at fertilization in the sea urchin Psammechinus miliaris: alterations of this Ca2+-signal by copper and 2,4,6-tribromophenol.

    PubMed

    Schäfer, Sabine; Bickmeyer, Ulf; Koehler, Angela

    2009-08-01

    During fertilization, eggs undergo a temporary rise in the intracellular concentration of free Ca(2+) ions. Using the membrane permeable acetoxymethylester of the fluorescent calcium indicator dye Fura-2, Fura-2 AM, the Ca(2+)-signal at fertilization was not detectable in eggs of the sea urchin Psammechinus miliaris. However, after treatment of the eggs with Fura-2 AM in combination with MK571, an inhibitor for multidrug resistance associated proteins, clear Ca(2+)-signals at fertilization could be measured without microinjection of the dye. We used this methodology to detect possible alterations of Ca(2+)-signalling at fertilization by exposure of eggs to environmental pollutants. For this purpose, the heavy metal copper, the bromophenol 2,4,6-tribromophenol, the organic compound bisphenol A and the polycyclic aromatic hydrocarbon phenanthrene were tested for their potential to inhibit fertilization success of P. miliaris. Copper and 2,4,6-tribromophenol showed a dose-dependent effect on fertilization rates of P. miliaris and significantly inhibited fertilization at 6.3 microM Cu(2+) and 1 microM 2,4,6-tribromphenol. Bisphenol A significantly inhibited fertilization success at 438 microM while phenanthrene had no effect up to 56 microM. 6.3 microM copper and 100 microM 2,4,6-tribromophenol significantly increased the Ca(2+)-signal at fertilization. This alteration may contribute to the reduced fertilization rates of P. miliaris after exposure to copper and 2,4,6-tribromophenol.

  13. Photographer : JPL Range : 4.2 million km. ( 2.6 million miles ) Jupiter's moon Europa, the size of

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Photographer : JPL Range : 4.2 million km. ( 2.6 million miles ) Jupiter's moon Europa, the size of earth's moon, is apparently covered by water ice, as indicated by ground spectrometers and its brightness. In this view, global scale dark sreaks discovered by Voyager 1 that criss-cross the the satelite are becoming visible. Bright rayed impact craters, which are abundant on Ganymede and Callisto, would be easily visible at this range, suggesting that Europa's surface is young and that the streaks are reflections of currently active internal dynamic processes.

  14. A Study on Alpha-Case Depth in Ti-6Al-2Sn-4Zr-2Mo

    NASA Astrophysics Data System (ADS)

    McReynolds, Kevin S.; Tamirisakandala, Seshacharyulu

    2011-07-01

    Isothermal oxidation experiments in air were performed on Ti-6Al-2Sn-4Zr-2Mo (Ti-6242) with a bimodal microstructure in the temperature range 811 K to 922 K (538 °C to 649 °C) for up to 500 hours, and α-case depths were quantified using metallography. Alpha-case depth followed a parabolic variation with time. Alpha-case depths in excess of 10 μm formed above 811 K (538 °C) and 100-hour exposures. An activation energy of 244 kJ/mol was estimated for diffusion of oxygen in the α phase of Ti-6242.

  15. MEISENHEIMER COMPLEX BETWEEN 2,4,6-TRINITROTOLUENE AND 3-AMINOPROPYLTRIETHOXYSILANE AND ITS USE FOR A PAPER-BASED SENSOR

    PubMed Central

    Hughes, Shantelle; Dasary, Samuel S. R.; Begum, Salma; Williams, Nya; Yu, Hongtao

    2015-01-01

    2,4,6-Trinitrotoluene (TNT) forms a red-colored Meisenheimer complex with 3-aminopropyltrenthoxysilane (APTES) both in solution and on solid phase. The TNT-APTES complex is unique since it forms yellow-colored complexes with 2,4,6-trinitrophenol and 4-nitrophenol, and no complex with 2,4-dinitrotoluene. The absorption spectrum of TNT-APTES has two absorption bands at 530 and 650 nm, while APTES complexes with 2,4,6-trinitrophenol and 4-nitrophenol have absorption maxima at around 420 nm, and no absorption change for 2,4-dinitrotoluene. The TNT-APTES complex facilitates the exchange of the TNT-CH3 proton/deuteron with solvent molecules. The red color of TNT-APTES is immediately visible at 1 µM of TNT. PMID:26380171

  16. Coordination chemistry of verdazyl radicals: group 12 metal (Zn, Cd, Hg) complexes of 1,4,5,6-tetrahydro-2,4-dimethyl-6-(2 pyridiyl)-1,2,4,5-tetrazin -3(2H)-one (pvdH3) and 1,5-dimethyl-3-(2 pyridil)-6-oxoverdazyl (pvd).

    PubMed

    Brook, D J; Fornell, S; Stevens, J E; Noll, B; Koch, T H; Eisfeld, W

    2000-02-07

    Ferricyanide oxidation of 1,4,5,6-tetrahydro-2,4-dimethyl-6-(2'-pyridyl)-1,2,4,5-tetrazin-3(2H)-one (pvdH3) produces the stable chelating free radical 1,5-dimethyl-3-(2'-pyridyl)-6-oxoverdazyl (pvd) as an orange solid. Combination of group 12 metal halides with the ligand pvdH3 in acetonitrile results in precipitation of metal complexes. The mercuric chloride complex crystallizes in the monoclinic space group P2(1/c) with unit cell dimensions a = 8.5768(8) A, b = 19.1718(17) A, c = 8.5956(8) A, beta = 90.405 degrees, and V = 1413.4(2) A3. The mercuric ion is tricoordinate with a distorted trigonal planar geometry. Cadmium iodide and zinc chloride induce ring opening of the tetrazine resulting in pentacoordinate complexes of a hydrazone ligand. The cadmium iodide complex crystallizes in the triclinic space group P1 with cell dimensions a = 7.7184(8) A, b = 8.0240(9) A, c = 13.348(2) A, alpha = 97.876(4) degrees, beta = 95.594(6) degrees, gamma = 107.304(6) degrees, and V = 773.40(21) A3. Oxidation of all three metal complexes produces verdazyl radicals. Metal coordination is indicated by small changes in the EPR spectrum and by changes in the UV-visible spectrum, in particular the changes in the position of bands in the visible region. The metal halide-pvd complexes can also be synthesized by direct combination of metal halides with the free radical.

  17. A previously unexposed forest soil microbial community degrades high levels of the pollutant 2,4,6-trichlorophenol.

    PubMed

    Sánchez, M A; Vásquez, M; González, B

    2004-12-01

    2,4,6-trichlorophenol (2,4,6-TCP) is a hazardous pollutant that is efficiently degraded by some aerobic soil bacterial isolates under laboratory conditions. The degradation of this pollutant in soils and its effect on the soil microbial community are poorly understood. We report here the ability of a previously unexposed forest soil microbiota to degrade high levels of 2,4,6-TCP and describe the changes in the soil microbial community found by terminal restriction fragment length polymorphism (T-RFLP) analysis. After 30 days of incubation, about 50% degradation of this pollutant was observed in soils amended with 50 to 5,000 ppm of 2,4,6-TCP. The T-RFLP analysis showed that the soil bacterial community was essentially unchanged after exposure to up to 500 ppm of 2,4,6-TCP. However, a significant decrease in richness was found with 2,000 and 5,000 ppm of 2,4,6-TCP, even though the removal of this pollutant remained high. The introduction of Ralstonia eutropha JMP134 or R. eutropha MS1, two efficient 2,4,6-TCP degraders, to this soil did not improve degradation of this pollutant, supporting the significant bioremediation potential of this previously unexposed, endogenous forest soil microbial community.

  18. Rate Coefficients of C2H with C2H4, C2H6, and H2 from 150 to 359 K

    NASA Technical Reports Server (NTRS)

    Opansky, Brian J.; Leone, Stephen R.

    1996-01-01

    Rate coefficients for the reactions C2H with C2H4, C2H6, and H2 are measured over the temperature range 150-359 K using transient infrared laser absorption spectroscopy. The ethynyl radical is formed by photolysis of C2H2 with a pulsed excimer laser at 193 nm, and its transient absorption is monitored with a color center laser on the Q(sub 11)(9) line of the A(sup 2) Pi-Chi(sup 2) Sigma transition at 3593.68 cm(exp -1). Over the experimental temperature range 150-359 K the rate constants of C2H with C2H4, C2H6, and H2 can be fitted to the Arrhenius expressions k(sub C2H4) = (7.8 +/- 0.6) x 10(exp -11) exp[(134 +/- 44)/T], k(sub C2H6) = (3.5 +/- 0.3) x 10(exp -11) exp[(2.9 +/- 16)/T], and k(sub H2) = (1.2 +/- 0.3) x 10(exp -11) exp[(-998 +/- 57)]/T cm(exp 3) molecule(exp -1) sec(exp -1). The data for C2H with C2H4 and C2H6 indicate a negligible activation energy to product formation shown by the mild negative temperature dependence of both reactions. When the H2 data are plotted together with the most recent high-temperature results from 295 to 854 K, a slight curvature is observed. The H2 data can be fit to the non-Arrhenius form k(sub H2) = 9.2 x 10(exp -18) T(sup 2.17 +/- 0.50) exp[(-478 +/- 165)/T] cm(exp 3) molecules(exp -1) sec(exp -1). The curvature in the Arrhenius plot is discussed in terms of both quantum mechanical tunneling of the H atom from H2 to the C2H radical and bending mode contributions to the partition function.

  19. Absorption spectra of vanadyl ion doped in MgNH 4PO 4·6H 2O (struvite) crystal

    NASA Astrophysics Data System (ADS)

    Agarwal, O. P.; Chand, Prem

    1984-10-01

    Results of Electron Paramagnetic Resonance (EPR) and optical absorption studies of VO 2+ ion doped in struvite at room liquid nitrogen temperatures are reported. Three preferential V= O bond directions in the crystal have been identified. The optical and EPR data have shown the formation of NH 4(PO 4VO(H 2O) 5 complex in the crystal as a result of VO 2+ doping. Correlating the optical and EPR data the molecular orbital coefficients are also obtained and discussed.

  20. Multigram-scale synthesis of an orthogonally protected 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose (AAT) building block.

    PubMed

    Christina, A E; Blas Ferrando, V M; de Bordes, F; Spruit, W A; Overkleeft, H S; Codée, J D C; van der Marel, G A

    2012-07-15

    Reported is the gram-scale synthesis of tert-butyldiphenylsilyl 4-(N-benzyloxycarbonyl)-amino-2-azido-2,4,6-trideoxy-β-D-galactopyranoside, which represents an orthogonally protected 2,4-diamino-D-fucose building block, a common constituent of various zwitterionic polysaccharides. The building block has been synthesized from D-glucosamine in 19% overall yield over 14 steps, requiring 5 chromatographic purifications. The key step in the synthesis is the introduction of the C-4 amino substituent, which has been accomplished by a one-pot three step procedure, involving regioselective C-3-O-trichloroacetimidate formation, C-4-O-triflation, and intramolecular substitution. The building block can be used as an acceptor and is readily transformed into a donor glycoside.

  1. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyride neurotoxicity is attenuated in mice overexpressing Bcl-2.

    PubMed

    Yang, L; Matthews, R T; Schulz, J B; Klockgether, T; Liao, A W; Martinou, J C; Penney, J B; Hyman, B T; Beal, M F

    1998-10-15

    The proto-oncogene Bcl-2 rescues cells from a wide variety of insults. Recent evidence suggests that Bcl-2 protects against free radicals and that it increases mitochondrial calcium-buffering capacity. The neurotoxicity of 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyride (MPTP) is thought to involve both mitochondrial dysfunction and free radical generation. We therefore investigated MPTP neurotoxicity in both Bcl-2 overexpressing mice and littermate controls. MPTP-induced depletion of dopamine and loss of [3H]mazindol binding were significantly attenuated in Bcl-2 overexpressing mice. Protection was more profound with an acute dosing regimen than with daily MPTP administration over 5 d. 1-Methyl-4-phenylpyridinium (MPP+) levels after MPTP administration were similar in Bcl-2 overexpressing mice and littermates. Bcl-2 blocked MPP+-induced activation of caspases. MPTP-induced increases in free 3-nitrotyrosine levels were blocked in Bcl-2 overexpressing mice. These results indicate that Bcl-2 overexpression protects against MPTP neurotoxicity by mechanisms that may involve both antioxidant activity and inhibition of apoptotic pathways.

  2. Photophysical Properties of a 1,2,3,4,5,6-Hexasubstituted Fullerene Derivative

    PubMed Central

    Chin, Khin K.; Chuang, Shih-Ching; Hernandez, Billy; Selke, Matthias; Foote, Christopher S.

    2008-01-01

    The photophysical properties of a novel 1,2,3,4,5,6-hexasusbstituted fullerene derivative (1) are examined in this study. In addition to the ground state absorption spectrum of 1 we report its triplet-triplet absorption spectrum and molar extinction coefficient (ΔεT-T), as well as the triplet quantum yield (ΦT), lifetime (τT), and energy (ET). The saturation of a single six-member ring on the fullerene cage results in significant changes in the triplet state properties as compared to that of pristine C60. The triplet-triplet absorption spectrum shows a hypsochromic shift in long wavelength absorption and both the triplet state lifetime and triplet quantum yield are decreased. The triplet energy was found to be similar to that of C60. In addition, the quantum yield (ΦΔ) of singlet oxygen generated by 1 was calculated and is found to be significantly less than in the case of C60. PMID:17181318

  3. (4R,6S)-2-Dihydromenisdaurilide is a Butenolide that Efficiently Inhibits Hepatitis C Virus Entry

    PubMed Central

    Chung, Chueh-Yao; Liu, Ching-Hsuan; Wang, Guey-Horng; Jassey, Alagie; Li, Chia-Lin; Chen, Lei; Yen, Ming-Hong; Lin, Chun-Ching; Lin, Liang-Tzung

    2016-01-01

    Without a vaccine, hepatitis C virus (HCV) remains a significant threat, putting 170–300 million carriers worldwide at risk of cirrhosis and hepatocellular carcinoma. Although the direct-acting antivirals targeting HCV replication have revolutionized the treatment of hepatitis C, several obstacles persist, including resistance development, potential side-effects, and the prohibitive cost that limits their availability. Furthermore, treatment of HCV re-infection in liver transplantation remains a significant challenge. Developing novel antivirals that target viral entry could help expand the scope of HCV therapeutics and treatment strategies. Herein, we report (4R,6S)-2-dihydromenisdaurilide (DHMD), a natural butenolide, as an efficient inhibitor of HCV entry. Specifically, DHMD potently inhibited HCV infection at non-cytotoxic concentration. Examination on the viral life cycle demonstrated that DHMD selectively targeted the early steps of infection while leaving viral replication/translation and assembly/release unaffected. Furthermore, DHMD did not induce an antiviral interferon response. Mechanistic dissection of HCV entry revealed that DHMD could inactivate cell-free virus, abrogate viral attachment, and inhibit viral entry/fusion, with the most pronounced effect observed against the viral adsorption phase as validated using ELISA and confocal microscopy. Due to its potency, DHMD may be of value for further development as an entry inhibitor against HCV, particularly for application in transplant setting. PMID:27426693

  4. 2,4,6-trichlorophenol (TCP) photobiodegradation and its effect on community structure.

    PubMed

    Zhang, Yongming; Pu, Xuejing; Fang, Miaomiao; Zhu, Jun; Chen, Lujun; Rittmann, Bruce E

    2012-07-01

    The mechanisms occurring in a photolytic circulating-bed biofilm reactor (PCBBR) treating 2,4,6-trichlorophenol (TCP) were investigated using batch experiments following three protocols: photodegradation alone (P), biodegradation alone (B), and intimately coupled photodegradation and biodegradation (P&B). Initially, the ceramic particles used as biofilm carriers rapidly adsorbed TCP, particularly in the B experiments. During the first 10 min, the TCP removal rate for P&B was equal to the sum of the rates for P and B, and P&B continued to have the greatest TCP removal, with the TCP concentration approaching zero only in the P&B experiments. When phenol, an easily biodegradable compound, was added along with TCP in order to promote TCP mineralization by means of secondary utilization, P&B was superior to P and B in terms of mineralization of TCP, giving 95% removal of chemical oxygen demand (COD). The microbial communities, examined by clone libraries, changed dramatically during the P&B experiments. Whereas Burkholderia xenovorans, a known degrader of chlorinated aromatics, was the dominant strain in the TCP-acclimated inoculum, it was replaced in the P&B biofilm by strains noted for biofilm formation and biodegrading non-chlorinated aromatics.

  5. SAGE Analysis of Transcriptome Responses in Arabidopsis Roots Exposed to 2,4,6-Trinitrotoluene1

    PubMed Central

    Ekman, Drew R.; Lorenz, W. Walter; Przybyla, Alan E.; Wolfe, N. Lee; Dean, Jeffrey F.D.

    2003-01-01

    Serial analysis of gene expression was used to profile transcript levels in Arabidopsis roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and each was sequenced to a depth of roughly 32,000 tags. More than 19,000 unique tags were identified overall. The second most highly induced tag (27-fold increase) represented a glutathione S-transferase. Cytochrome P450 enzymes, as well as an ABC transporter and a probable nitroreductase, were highly induced by TNT exposure. Analyses also revealed an oxidative stress response upon TNT exposure. Although some increases were anticipated in light of current models for xenobiotic metabolism in plants, evidence for unsuspected conjugation pathways was also noted. Identifying transcriptome-level responses to TNT exposure will better define the metabolic pathways plants use to detoxify this xenobiotic compound, which should help improve phytoremediation strategies directed at TNT and other nitroaromatic compounds. PMID:14551330

  6. Precipitation hardening of an Al-4.2 wt% Mg-0.6 wt% Cu alloy

    SciTech Connect

    Ratchev, P.; Verlinden, B.; Houtte, P. van; Smet, P. de

    1998-06-12

    The precipitation hardening of an experimental Al-4.2 wt % Mg-0.6 wt % Cu alloy has been studied. After a first initial jump, the yield strength increases almost linearly with the logarithm of the ageing time and a peak of hardness is reached after 11 days at 180 C. Special attention is given to the precipitation hardening during the early stage of ageing. It has been shown that S{double_prime} phase can be formed heterogeneously on dislocation loops and helices and a new mechanism of precipitation hardening due to this S{double_prime} phase precipitation is proposed. The precipitation of S{double_prime} on dislocations is the predominant cause of strengthening during the initial stage of precipitation hardening (up to 30 min at 180 C). Guinier-Preston-Bagaryatsky (GPB) zones (or better, the recently introduced Cu/Mg clusters) also appear in the initial stage, but their contribution to the hardness, which up to now as considered to be predominant, is shown to be smaller than the one of the S{double_prime} precipitates. Since the density of the S{double_prime} nucleation sites is related to the amount of dislocations, this mechanism is important in the case of a bake hardening treatment when ageing is preceded by cold deformation. Uniform S{double_prime} precipitation has also been found at the later ageing stage, which suggests that the contribution of S{double_prime} to the precipitation hardening at that stage is not less important.

  7. Germination and seedling development of switchgrass and smooth bromegrass exposed to 2,4,6-trinitrotoluene.

    PubMed

    Peterson, M M; Horst, G L; Shea, P J; Comfort, S D

    1998-01-01

    It is estimated that explosives contaminate approximately 0.82 million cubic metres of soil at former military installations throughout the US; major contaminants often include 2,4,6-trinitrotoluene (TNT) and its degradation products. At some sites, phytoremediation may be a viable option to incineration or other costly remediation treatments. Grasses may be particularly suited for remediation because of their growth habit and adaptability to a wide range of soil and climate conditions. We characterized the effects of TNT on germination and early seedling development of switchgrass and smooth bromegrass to evaluate their potential use on contaminated sites. Switchgrass and smooth bromegrass seeds were germinated in nutrient-free agar containing 0 to 60 mg TNT litre(-1). Smooth bromegrass germination decreased as TNT concentration increased, while switchgrass germination was unaffected by TNT. Concentrations up to 15 mg TNT litre(-1) did not affect switchgrass root growth rate, but bromegrass root growth was reduced at TNT concentrations above 7.5 mg litre(-1). At 7.5 mg TNT litre(-1), however, shoot growth rate was reduced in both species. Examination at 20-fold magnification revealed switchgrass radicles were unaffected by TNT, while smooth bromegrass radicles appeared slightly swollen. Results indicate switchgrass is more tolerant of TNT than smooth bromegrass, but the establishment of both species may be limited to soil containing less than 50 mg kg(-1) of extractable TNT.

  8. Sonochemical synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)

    SciTech Connect

    Lee, Kien-Yin

    1996-05-01

    The synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from trichlorotrinitrobenzene (TCTNB) in toluene and ammonium hydroxide solution under the influence of ultrasonic waves was investigated. When the two-phase reaction mixture was irradiated with high intensity ultrasound at ambient temperature, fine-particle TATB (FP-TATB) was produced. This sonochemically produced TATB powder is lemon color in appearance and was analyzed to have the same explosive properties as reported in the literature. That is, it is insensitive to impact stimuli, and thermally stable. The median particle diameter of FP-TATB was calculated to be around 14 {mu}m, and the powder can be pressed to a density of 1.82 g/cm{sup 3} without a binder. The amination process is simple and requires neither the monitoring of the ammonia gas pressure nor the controlling of the reaction temperature during amination reaction, and we anticipate no problem in large scale production of FP-TATB.

  9. Synthesis and luminescence properties of double perovskite Sr2ZnMoO6:Mn4+ deep red phosphor

    NASA Astrophysics Data System (ADS)

    Cao, Renping; Ceng, Xiangfeng; Huang, Jijun; Ao, Hui; Zheng, Guotai; Yu, Xiaoguang; Zhang, Xinqin

    2016-12-01

    A double perovskite Sr2ZnMoO6:Mn4+ (SZM:Mn4+) phosphor is synthesized by high-temperature solid-state reaction method in air. Emission band peaking at ∼705 nm of SZM:Mn4+ phosphor in the range of 650-790 nm is attributed to the 2E → 4A2 transition of Mn4+ ion with activated different lattice vibration modes. Three excitation bands in the range of 210-610 nm are assigned to the O2- → Mn4+ charge transfer and the 4A2 → (4T1, 2T2, and 4T2) transition of Mn4+ ion. The optimal Mn4+ ion concentration is ∼0.8 mol% in SZM:Mn4+ phosphor. Fluorescence lifetime of SZM:Mn4+ phosphor decreases from ∼132 μs to 108 μs with increasing Mn4+ ion concentration in the range of 0.2-1.0 mol%. Time-resolved spectra and fluorescence lifetime data indicate that luminescent center is caused by Mn4+ ion. The luminous mechanism of SZM:Mn4+ phosphor is explained by Tanabe-Sugano energy level diagram of Mn4+ ion. The results are useful to understand the influences of the neighboring coordination environment around Mn4+ and host crystal structure to the luminescence properties of Mn4+ ion and develop other novel Mn4+-doped materials.

  10. Workers exposed to thermal degradation products of TDI- and MDI-based polyurethane: biomonitoring of 2,4-TDA, 2,6-TDA, and 4,4'-MDA in hydrolyzed urine and plasma.

    PubMed

    Dalene, M; Skarping, G; Lind, P

    1997-08-01

    The aim of the study was to investigate biomarkers of exposure to thermal degradation products of 2,4- and 2,6-toluene diisocyanate (TDI)- and 4,4'-methylenediphenyl diisocyanate (MDI)-based polyurethane and the toxicokinetics of these products. Blood and urine were collected from 15 factory workers exposed to thermal degradation products of MDI-based polyurethane glue and TDI-based flexible foam. Four of these workers were also studied during an exposure-free period. Urine and plasma were analyzed after acidic hydrolysis and the concentrations of the isocyanates' corresponding amines, 2,4-, 2,6-toluenediamine (TDA), and 4,4'-methylenedianiline (MDA), were determined as derivatives of pentafluoropropionic anhydride by gas chromatography using chemical ionization mass spectrometry monitoring negative ions. Urinary elimination rates were in the range of < 0.01-5.7 micrograms of 2,4-TDA per hour, < 0.01-3.5 micrograms of 2,6-TDA per hour, and < 0.01-1.6 micrograms of 4,4'-MDA per hour. Plasma levels were in the range of < 0.1-5.5 ng of 2,4-TDA per mL, < 0.1-2.3 ng of 2,6-TDA per mL, and < 0.1-45 ng of 4,4'-MDA per mL. The urinary half-lives of 4,4'-MDA for four of the workers were found to be 59, 61, 73, and 82 hours. The half-lives of 4,4'-MDA in plasma were 10, 14, 16, and 22 days. Elimination rate peaks of 2,4-TDA, 2,6-TDA, and 4,4'-MDA in urine varied during and between workdays. The individual variation in plasma concentrations of 2,4-TDA, 2,6-TDA, and 4,4'-MDA with time was small, but between individuals the variation was great.

  11. Biodegradation of 2,4,6-trichlorophenol and associated hydraulic conductivity reduction in sand-bed columns.

    PubMed

    Antizar-Ladislao, Blanca; Galil, Noah I

    2006-06-01

    The aim of this research was to investigate the long-term hydraulic conductivity changes in sand-bed columns exposed to 2,4,6-trichlorophenol (TCP). Continuous flow laboratory studies were conducted using sand-bed columns (15 cm i.d.; 200 cm length) at 20+/-1 degrees C during 365 d. The influence of (i) initial loads of 2,4,6-TCP (15, 30, 45 and 60 mg kg(-1) of 2,4,6-TCP), and (ii) recirculating water velocity (0.09, 0.56 and 1.18 cm min(-1)) on the biodegradation of 2,4,6-TCP and hydraulic conductivity changes in the sand-bed columns were investigated. The experimental results indicated that biodegradation of 2,4,6-TCP followed pseudo-first-order kinetics in the range of k(1)=0.01-1.64 d(-1), and it was influenced by initial load (p<0.01) and recirculating water velocity (p<0.01). Indigenous microbial biomass growth and changes resulted in a spatial (180 cm) and temporal (365 d) reduction of hydraulic conductivity in the sand-bed columns by up to two orders of magnitude during biodegradation of 2,4,6-TCP. The fastest hydraulic conductivity reductions were observed in the sand-bed column operated at the highest recirculating water velocity and highest cumulative load of 2,4,6-TCP following 365 d of continuous treatment (p<0.05).

  12. Corrosion behavior and biocompatibility of nanostructured TiO2 film on Ti6Al4V.

    PubMed

    Karpagavalli, Ramji; Zhou, Anhong; Chellamuthu, Prithiviraj; Nguyen, Kytai

    2007-12-15

    The corrosion behavior and cell adhesion property of nanostructured TiO2 films deposited electrolytically on Ti6Al4V were examined in the present in vitro study. The nanostructured TiO2 film deposition on Ti6Al4V was achieved via peroxoprecursors. SEM micrographs exhibit the formation of amorphous and crystallite TiO2 nanoparticles on Ti6Al4V before and after being annealed at 500 degrees C. Corrosion behavior of TiO2-deposited and uncoated Ti6Al4V was evaluated in freely aerated Hank's solution at 37 degrees C by the measurement and analysis of open-circuit potential variation with time, Tafel plots, and electrochemical impedance spectroscopy. The electrochemical results indicated that nano-TiO2 coated Ti6Al4V showed a better corrosion resistance in simulated biofluid than uncoated Ti6Al4V. Rat bone cells and human aortic smooth muscle cells were grown on these substrates to study the cellular responses in vitro. The SEM images revealed enhanced cell adhesion, cell spreading, and proliferation on nano-TiO2 coated Ti6Al4V compared to those grown on uncoated substrates for both cell lines. These results suggested that nanotopography produced by deposition of nanostructured TiO2 onto Ti alloy surfaces might enhance corrosion resistance, biocompatibility, and cell integration for implants made of Ti alloys.

  13. Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes

    PubMed Central

    Lin, He; Yao, Chao; Zhang, Xianping; Zhang, Haitao; Wang, Dongliang; Zhang, Qianjun; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo

    2014-01-01

    Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 104 A/cm2 in 10 T and 4.3 × 104 A/cm2 in 14 T at 4.2 K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications. PMID:24663054

  14. Structural and photophysical properties of HPPCO (4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one) derivatives.

    PubMed

    Jeong, Yong-Kwang; Kim, Min-Ah; Lee, Hyo-Sung; Kim, Jong-Moon; Lee, Sung Woo; Kang, Jun-Gill

    2015-01-05

    Proton-substitution effects of 4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one (HPPCO) on structural and photophysical properties were presented. HPPCO crystallized in the orthorhombic space group Pbca with an intermolecular hydrogen bonding between OH and oxygen atom of the carbonyl. The proton-substituted derivatives, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl acetate (OPPCA) and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl benzoate (OPPCB), crystallized in the monoclinic P2₁/c space group. For OPPCA and OPPCB, a weak interaction between carbonyl oxygen atom in the substituted group and carbon atom in the fused ring was responsible for three-dimensional arrangements. In addition, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl furan-2-carboxylate (OPPCF), and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl naphthoate (OPPCN) were also synthesized. HPPCO and the four derivatives excited by ultraviolet (UV) light produced blue emission. Proton substitution of the OH group significantly increased the radiative transitions and moderately decreased the non-radiative transitions. Consequently the luminescence quantum yields of the derivatives enhanced more than 4.6-fold, no matter what the groups were substituted. Structural and optical properties were further determined using density functional theory (DFT) and ZINDO calculations. The planar structure of the pyridocarbazole-fused ring resulted in π→π(*) electronic transitions within the main frame, with an additional transition from the n(O) of carbonyl to the π(*) of the main frame. The three excited states that arose from these transitions were responsible for the blue luminescence.

  15. Soil Sorption and Plant Uptake of 2,4,6-Trinitrotoluene

    DTIC Science & Technology

    1988-09-01

    growth , Each soil batch received 50 ug N an (NH4 ) 2 SO4 , 25 ug P as Na•l 2 PO4 , and 25 ug K as K11 per gram of soil, This corresponds to a rate of 56 kg...King 1974; Won, DiSalvo, and Ng 1976), inhibitory to plant growth (Laklings and Gan 1981; Palazzo at al. 1985; Schott and Worthly 1974), and, in some...may be magnified, Toxicity of TNT wastes to duckweed (Lemna • •r2usiAl) has been demonstrated by Schott and Worthley (1974), and depression of yields

  16. Raman and infrared spectroscopic study of synthetic ungemachite, K3Na8Fe(SO4)6(NO3)2·6H2O

    NASA Astrophysics Data System (ADS)

    Vargas Jentzsch, Paul; Ciobotă, Valerian; Bolanz, Ralph Michael; Kampe, Bernd; Rösch, Petra; Majzlan, Juraj; Popp, Jürgen

    2012-08-01

    Iron is an important element usually found in atmospheric particulate matter, and its occurrence can be attributed to both natural and anthropogenic sources. It is an accepted fact that the atmospheric particles interact with water and other atmospheric components, therefore dissolution-crystallization processes can be expected. In this work, considering specially that low pH values are characteristic of aerosol solutions, we postulate that the rare mineral ungemachite, K3Na8Fe(SO4)6(NO3)2·6H2O can crystallize in atmosphere. The Raman and infrared spectra of synthetic ungemachite are presented and the band assignments are proposed and discussed. This is the first time that a synthetic method for ungemachite is reported.

  17. Synthesis and in vitro anticancer evaluation of some 4,6-diamino-1,3,5-triazine-2-carbohydrazides as Rad6 ubiquitin conjugating enzyme inhibitors.

    PubMed

    Kothayer, Hend; Spencer, Sebastian M; Tripathi, Kaushlendra; Westwell, Andrew D; Palle, Komaraiah

    2016-04-15

    Series of 4-amino-6-(arylamino)-1,3,5-triazine-2-carbohydrazides (3a-e) and N'-phenyl-4,6-bis(arylamino)-1,3,5-triazine-2-carbohydrazides (6a-e), for ease of readership, we will abbreviate our compound names as 'new triazines', have been synthesized, based on the previously reported Rad6B-inhibitory diamino-triazinylmethyl benzoate anticancer agents TZ9 and 4-amino-N'-phenyl-6-(arylamino)-1,3,5-triazine-2-carbohydrazides. Synthesis of the target compounds was readily accomplished in two steps from either bis-aryl/aryl biguanides via reaction of phenylhydrazine or hydrazinehydrate with key 4-amino-6-bis(arylamino)/(arylamino)-1,3,5-triazine-2-carboxylate intermediates. These new triazine derivatives were evaluated for their abilities to inhibit Rad6B ubiquitin conjugation and in vitro anticancer activity against several human cancer cell lines: ovarian (OV90 and A2780), lung (H1299 and A549), breast (MCF-7 and MDA-MB231) and colon (HT29) cancer cells by MTS assays. All the 10 new triazines exhibited superior Rad6B inhibitory activities in comparison to selective Rad6 inhibitor TZ9 that was reported previously. Similarly, new triazines also showed better IC50 values in survival assays of various tumor cell lines. Particularly, new triazines 6a-c, exhibited lower IC50 (3.3-22 μM) values compared to TZ9.

  18. Novel opioid peptide derived antagonists containing (2S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2S)-Mdcp].

    PubMed

    Ghosh, Animesh; Luo, Jie; Liu, Chen; Weltrowska, Grazyna; Lemieux, Carole; Chung, Nga N; Lu, Yixin; Schiller, Peter W

    2008-09-25

    A synthesis of the novel tyrosine analogue (2 S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2 S)-Mdcp] (15) was developed. In (2 S)-Mdcp, the amino and hydroxyl groups of 2',6'-dimethyltyrosine are replaced by a methyl and a carbamoyl group, respectively, and its substitution for Tyr (1) in opioid agonist peptides resulted in compounds showing antagonism at all three opioid receptors. The cyclic peptide (2 S)-Mdcp-c[D-Cys-Gly-Phe(pNO 2)-D-Cys]NH 2 (1) was a potent and selective mu antagonist, whereas (2 S)-Mdcp-c[D-Pen-Gly-Phe(pF)-Pen]-Phe-OH (3) showed subnanomolar delta antagonist activity and extraordinary delta selectivity.

  19. Rietveld refinement, electronic structure and ionic conductivity of Sr{sub 4}La{sub 6}(SiO{sub 4}){sub 6}F{sub 2} and Sr{sub 4}La{sub 6}(SiO{sub 4}){sub 6}O ceramics

    SciTech Connect

    Boughzala, Khaled; Debbichi, Mourad; Njema, Hela; Bouzouita, Khaled

    2016-07-15

    In this paper, we report the effect of the tunnel anions on the ionic conductivity of Strontium-Lanthanum silicate apatites. The Sr{sub 4}La{sub 6}(SiO{sub 4}){sub 6}F{sub 2} and Sr{sub 4}La{sub 6}(SiO{sub 4}){sub 6}O ceramics were prepared by the solid state reaction method. X-ray diffraction, NMR spectroscopy and Raman measurements were performed to investigate the crystal structure and vibrational active modes. Moreover, the electronic structures of the crystals were evaluated by the first-principles quantum mechanical calculation based on the density functional theory. Finally, the ionic conductivity was studied according to the complex impedance method. - Graphical abstract: The relaxed primitive unit cell for Sr{sub 4}La{sub 6}Fap. Display Omitted.

  20. Ethyl 3-(6-phenyl-4λ4-1,2-dithiolo[1,5-b][1,2,4]dithia­zol-2-yl)propanoate

    PubMed Central

    Marković, Rade; Rašović, Aleksandar; Steel, Peter J.

    2008-01-01

    The title compound, C15H15NO2S3, exists in a bicyclic form, with resonance contributions from two monocyclic forms, each without a second S—S bond. The trithiapentalene heterocyclic ring system is planar, with a mean deviation of 0.014 (2) Å from the mean plane, and is inclined to the plane of the attached phenyl ring at an angle of 17.24 (7)°. PMID:21200742

  1. Conformational Isomerism of trans-[Pt(NH2C6H11)2I2] and the Classical Wernerian Chemistry of [Pt(NH2C6H11)4]X2 (X = Cl, Br, I)1

    PubMed Central

    Johnstone, Timothy C.; Lippard, Stephen J.

    2012-01-01

    X-ray crystallographic analysis of the compound trans-[Pt(NH2C6H11)2I2] revealed the presence of two distinct conformers within one crystal lattice. This compound was studied by variable temperature NMR spectroscopy to investigate the dynamic interconversion between these isomers. The results of this investigation were interpreted using physical (CPK) and computational (molecular mechanics and density functional theory) models. The conversion of the salts [Pt(NH2C6H11)4]X2 into trans-[Pt(NH2C6H11)2X2] (X = Cl, Br, I) was also studied and is discussed here with an emphasis on parallels to the work of Alfred Werner. PMID:23554544

  2. Synthesis and in vitro anticancer activity of 6,7-methylenedioxy (or 5-hydroxy-6-methoxy)-2-(substituted selenophenyl)quinolin-4-one analogs.

    PubMed

    Chen, Chien-Ting; Hsu, Mei-Hua; Cheng, Yung-Yi; Liu, Chin-Yu; Chou, Li-Chen; Huang, Li-Jiau; Wu, Tian-Shung; Yang, Xiaoming; Lee, Kuo-Hsiung; Kuo, Sheng-Chu

    2011-12-01

    6,7-Methylenedioxy (or 5-hydroxy-6-methoxy)-2-(substituted selenophenyl)quinolin-4-ones and their isosteric compounds were synthesized and evaluated for anticancer activity. Structure-activity relationships (SAR) of these compounds were established. Among all tested compounds, 6,7-methylenedioxy-2-(5-methylselenophen-2-yl)quinolin-4-one (4d) was found to be the most promising anticancer agent. In screening against NCI's 60 human tumor cell line panel, 4d exhibited highly selective and potent inhibitory activity against MDA-MB-435 melanoma. Furthermore, the results of COMPARE analysis suggested that 4d is an antimitotic agent with a different mechanism of action from the conventional antimitotic agents, such as colchicine, vinca alkaloids and paclitaxel. Therefore, 4d was identified as a new lead compound that merits further optimization.

  3. Crystal structure of 2-amino-4,6-di-meth-oxy-pyrimidinium thio-phene-2-carboxyl-ate.

    PubMed

    Rajam, Ammaiyappan; Muthiah, P T; Butcher, Ray J; Jasinski, Jerry P

    2015-07-01

    In the title salt, C6H10N3O2 (+)·C5H3O2S(-), the 2-amino-4,6-di-meth-oxy-pyrimidinium cation inter-acts with the carboxyl-ate group of the thio-phene-2-carboxyl-ate anion through a pair of N-H⋯O hydrogen bonds, forming an R 2 (2)(8) ring motif. These motifs are centrosymmetrically paired via N-H⋯O hydrogen bonds, forming a complementary DDAA array. The separate DDAA arrays are linked by π-π stacking inter-actions between the pyrimidine rings, as well as by a number of weak C-H⋯O and N-H⋯O inter-actions. In the anion, the dihedral angle between the ring plane and the CO2 group is 11.60 (3)°. In the cation, the C atoms of methoxy groups deviate from the ring plane by 0.433 (10) Å.

  4. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  5. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  6. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  7. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  8. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  9. Toxicity of 2,6-Di-tert-butyl-4-Nitrophenol (DBNP).

    PubMed

    Alexander, W K; Briggs, G B; Still, K R; Jederberg, W W; MacMahon, K; Baker, W H; Mackerer, C

    2001-04-01

    U.S. Navy submarines reported a yellowing of metal surfaces on their internal surfaces. The yellowing was initially identified on the painted steel bulkheads but further examination indicated that it was not limited to steel surfaces and included bedding, thread tape, Formica, plastisol covered hand-wheels, and aluminum lockers. Crew members also reported to the medical department that their skin turned yellow when they came in contact with these contaminated surfaces and requested information on the effects of exposure. Studies conducted by General Dynamics' Electric Boat Division (EBD) determined that the agent was 2,6-Di-tertbutyl-4-Nitrophenol (DBNP). 2,6-Di-butylphenol (DBP) is an antioxidant additive used in lubricating oils and hydraulic fluids. In the enclosed atmosphere of a submarine, the oil mist could be spread throughout the boat by venting the lube oil to the atmosphere. Submarines use electrostatic precipitators (ESP) to clean the air of particulate materials. During passage through the ESP, oil mist containing DBP is nitrated to DBNP, which is then moved throughout the boat in the ventilation system. Analysis of the EBD data indicated 24-hour exposure concentrations to be in the range of <3.0 to 122 ppb in the laboratory and submarine settings. Submarine crews may be exposed to these concentrations for as many as 24 hours/ day for 90 days during underway periods. Toxicity studies regarding the oral and dermal uptake of DBNP were conducted. From the literature the lethal dose to 50 percent of the population (LD50) of DBNP (rat) was reported by Vesselinovitch et al. in 1961 to be 500 mg/kg. Our studies indicated that the LD50 is in the range of 80 mg/kg in the rat. Our work also includes dermal absorption studies, which indicated that DBNP is not well absorbed through intact skin. Within this study, no no-observable adverse effect level (NOAEL) or lowest observable adverse effect level (LOAEL) was identified. Calculation of a reference dose was

  10. Structural and photophysical properties of HPPCO (4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one) derivatives

    NASA Astrophysics Data System (ADS)

    Jeong, Yong-Kwang; Kim, Min-Ah; Lee, Hyo-Sung; Kim, Jong-Moon; Lee, Sung Woo; Kang, Jun-Gill

    2015-01-01

    Proton-substitution effects of 4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one (HPPCO) on structural and photophysical properties were presented. HPPCO crystallized in the orthorhombic space group Pbca with an intermolecular hydrogen bonding between OH and oxygen atom of the carbonyl. The proton-substituted derivatives, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl acetate (OPPCA) and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl benzoate (OPPCB), crystallized in the monoclinic P21/c space group. For OPPCA and OPPCB, a weak interaction between carbonyl oxygen atom in the substituted group and carbon atom in the fused ring was responsible for three-dimensional arrangements. In addition, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl furan-2-carboxylate (OPPCF), and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl naphthoate (OPPCN) were also synthesized. HPPCO and the four derivatives excited by ultraviolet (UV) light produced blue emission. Proton substitution of the OH group significantly increased the radiative transitions and moderately decreased the non-radiative transitions. Consequently the luminescence quantum yields of the derivatives enhanced more than 4.6-fold, no matter what the groups were substituted. Structural and optical properties were further determined using density functional theory (DFT) and ZINDO calculations. The planar structure of the pyridocarbazole-fused ring resulted in π → π* electronic transitions within the main frame, with an additional transition from the n(O) of carbonyl to the π* of the main frame. The three excited states that arose from these transitions were responsible for the blue luminescence.

  11. Transformation of 2,4,6-trinitrotoluene in soil in the presence of the earthworm Eisenia andrei

    SciTech Connect

    Renoux, A.Y.; Sarrazin, M.; Hawari, J.; Sunahara, G.I.

    2000-06-01

    The ability of the earthworm Eisenia andrei to metabolize 2,4,6-trinitrotoluene (TNT) was studied in experiments with TNT-spiked soils, dermal contact tests, and with an in vitro assay. Lethality of TNT in a forest sandy soil was first determined. Then TNT at lethal and sublethal concentrations was applied to the same soil and was monitored along with its metabolites in extracts of soil and earthworm tissue for up to 14 d post application. High performance liquid chromatography-ultra violet analyses indicated that TNT was transformed in the presence of E. andrei by a reductive pathway to 2-amino-3,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), 2,4-diamino-6-nitrotoluene (2.4-DANT), and traces of 2,6-diamino-4-nitrotoluene (2,6-DANT) in earthworm tissues. This transformation could be explained by either a metabolic mechanism within the earthworm or by the enhancement of an earthworm-associated microbial activity or both. The TNT concentrations decreased from the spiked soils. However, the monoamino-dinitrotoluene (2-ADNT and 4-ADNT) concentrations increased with exposure duration and were dependent on the initial TNT soil concentrations. This was also observed to a lesser extent in the TNT-spiked soils with no earthworms present. The biotransformation of TNT into 2-ADNT, 4-ADNT, and 2,4-DANT and the presence of these metabolites in E. andrei after dermal contact on TNT-spiked filter paper showed that dermal uptake can be a significant exposure route for TNT. In vitro experiments showed that earthworm homogenate could metabolize TNT and form 2-ADNT and 4-ADNT at room temperature and at 37 C. This effect was inhibited by heat inactivation prior to incubation or by incubation at 4 C, suggesting that the biotransformation of TNT in the presence of E. andrei may be enzymatic in nature.

  12. Adipic acid-2,4-diamino-6-(4-meth-oxy-phen-yl)-1,3,5-triazine (1/2).

    PubMed

    Thanigaimani, Kaliyaperumal; Razak, Ibrahim Abdul; Arshad, Suhana; Jagatheesan, Rathinavel; Santhanaraj, Kulandaisamy Joseph

    2012-10-01

    The asymmetric unit of the title compound, 2C(10)H(11)N(5)O·C(6)H(10)O(4), consists of a 2,4-diamino-6-(4-meth-oxy-phen-yl)-1,3,5-triazine mol-ecule and one-half mol-ecule of adipic acid which lies about an inversion center. The triazine ring makes a dihedral angle of 12.89 (4)° with the adjacent benzene ring. In the crystal, the components are linked by N-H⋯O and O-H⋯N hydrogen bonds, thus generating a centrosymmetric 2 + 1 unit of triazine and adipic acid mol-ecules with R(2) (2)(8) motifs. The triazine mol-ecules are connected to each other by N-H⋯N hydrogen bonds, forming an R(2) (2)(8) motif and a supra-molecular ribbon along the c axis. The 2 + 1 units and the supra-molecular ribbons are further inter-linked by weak N-H⋯O, C-H⋯O and C-H⋯π inter-actions, resulting in a three-dimensional network.

  13. Decomposition of some polynitro arenes initiated by heat and shock Part I. 2,4,6-Trinitrotoluene.

    PubMed

    Varga, Róbert; Zeman, Svatopluk

    2006-05-20

    Samples of 2,4,6-trinitrotoluene (TNT) exposed to heat or to shock and residues after their detonation have been analyzed chromatographically (LC-UV and LC/MS). It was found that the main identified decomposition intermediates are identical in all the three cases. 4,6-Dinitro-2,1-benzoisoxazole and 2,4,6-trinitrobenzaldehyde are the most reactive from them. It has been stated that the chemical micro-mechanism of the primary fragmentations of shock-exposed TNT molecules and/or its detonation transformation should be the same as in the case of its low-temperature thermal decomposition.

  14. Software Design Document Vehicle Simulation CSCI (5). Volume 3, Sections 2.5.4 - 2.6.18.12.1

    DTIC Science & Technology

    1991-06-01

    vec sub Section 2.6.2.65 vec mag3 /simnet/common/include/global/sim macros.h zero qet-new velocities Section 2.5.12.29.3 f mat copy Section 2.6.2.12.1...Section 2.1.2.2.3.1.1 vehicle place Section 2.5.19.1.2 v_mag Macro defined in /simnet/releasesrclibsrc/include/dyn state.h mag3 Macro defined in

  15. Aerobic Degradation of 2,4,6-Trinitrotoluene by Enterobacter cloacae PB2 and by Pentaerythritol Tetranitrate Reductase

    PubMed Central

    French, Christopher E.; Nicklin, Stephen; Bruce, Neil C.

    1998-01-01

    Enterobacter cloacae PB2 was originally isolated on the basis of its ability to utilize nitrate esters, such as pentaerythritol tetranitrate (PETN) and glycerol trinitrate, as the sole nitrogen source for growth. The enzyme responsible is an NADPH-dependent reductase designated PETN reductase. E. cloacae PB2 was found to be capable of slow aerobic growth with 2,4,6-trinitrotoluene (TNT) as the sole nitrogen source. Dinitrotoluenes were not produced and could not be used as nitrogen sources. Purified PETN reductase was found to reduce TNT to its hydride-Meisenheimer complex, which was further reduced to the dihydride-Meisenheimer complex. Purified PETN reductase and recombinant Escherichia coli expressing PETN reductase were able to liberate nitrogen as nitrite from TNT. The ability to remove nitrogen from TNT suggests that PB2 or recombinant organisms expressing PETN reductase may be useful for bioremediation of TNT-contaminated soil and water. PMID:9687442

  16. Aerobic degradation of 2,4,6-trinitrotoluene by Enterobacter cloacae PB2 and by pentaerythritol tetranitrate reductase

    SciTech Connect

    French, C.E.; Bruce, N.C.; Nicklin, S.

    1998-08-01

    Enterobacter cloacae PB2 was originally isolated on the basis of its ability to utilize nitrate esters, such as pentaerythritol tetranitrate (PETN) and glycerol trinitrate, as the sole nitrogen source for growth. The enzyme responsible is an NADPH-dependent reductase designated PETN reductase. E. cloacae PB2 was found to be capable of slow aerobic growth with 2,4,6-trinitrotoluene (TNT) as the sole nitrogen source. Dinitrotoluenes were not produced and could not be used as nitrogen sources. Purified PETN reductase was found to reduce TNT to its hydride-Meisenheimer complex, which was further reduced to the dihydride-Meisenheimer complex. Purified PETN reductase and recombinant Escherichia coli expressing PETN reductase were able to liberate nitrogen as nitrite from TNT. The ability to remove nitrogen from TNT suggests that PB2 or recombinant organisms expressing PETN reductase may be useful for bioremediation of TNT-contaminated soil and water.

  17. Structures of Exocyclic R,R- and S,S-N6,N6-(2,3-Dihydroxybutan-1,4-diyl)-2′-Deoxyadenosine Adducts Induced by 1,2,3,4-Diepoxybutane

    PubMed Central

    2015-01-01

    1,3-Butadiene (BD) is an industrial and environmental chemical present in urban air and cigarette smoke, and is classified as a human carcinogen. It is oxidized by cytochrome P450 to form 1,2,3,4-diepoxybutane (DEB); DEB bis-alkylates the N6 position of adenine in DNA. Two enantiomers of bis-N6-dA adducts of DEB have been identified: R,R-N6,N6-(2,3-dihydroxybutan-1,4-diyl)-2′-deoxyadenosine (R,R-DHB-dA), and S,S-N6,N6-(2,3-dihydroxybutan-1,4-diyl)-2′-deoxyadenosine (S,S-DHB-dA) [SeneviratneU., AntsypovichS., DorrD. Q., DissanayakeT., KotapatiS., and TretyakovaN. (2010) Chem. Res. Toxicol.23, 1556−156720873715]. Herein, the R,R-DHB-dA and S,S-DHB-dA adducts have been incorporated into the 5′-d(C1G2G3A4C5X6A7G8A9A10G11)-3′:5′-d(C12T13T14C15T16T17G18T19C20C21G22)-3′ duplex [X6 = R,R-DHB-dA (R6) or S,S-DHB-dA (S6)]. The structures of the duplexes were determined by molecular dynamics calculations, which were restrained by experimental distances obtained from NMR data. Both the R,R- and S,S-DHB-dA adducts are positioned in the major groove of DNA. In both instances, the bulky 3,4-dihydroxypyrrolidine rings are accommodated by an out-of-plane rotation about the C6-N6 bond of the bis-alkylated adenine. In both instances, the directionality of the dihydroxypyrrolidine ring is evidenced by the pattern of NOEs between the 3,4-dihydroxypyrrolidine protons and DNA. Also in both instances, the anti conformation of the glycosyl bond is maintained, which combined with the out-of-plane rotation about the C6-N6 bond, allows the complementary thymine, T17, to remain stacked within the duplex, and form one hydrogen bond with the modified base, between the imine nitrogen of the modified base and the T17 N3H imino proton. The loss of the second Watson–Crick hydrogen bonding interaction at the lesion sites correlates with the lower thermal stabilities of the R,R- and S,S-DHB-dA duplexes, as compared to the corresponding unmodified duplex. The reduced base stacking at the

  18. Crystal structure of 5-(5,6-di-hydro-benzo[4,5]imidazo[1,2-c]quinazolin-6-yl)-2-meth-oxy-phenol.

    PubMed

    Adam, Farook; Arafath, Md Azharul; Rosenani, A Haque; Razali, Mohd R

    2015-12-01

    In the mol-ecule of the title compound, C21H17N3O2, the 5,6-di-hydro-benzimidazo[1,2-c]quinazoline moiety is disordered over two orientations about a pseudo-mirror plane, with a refined occupancy ratio of 0.863 (2):0.137 (2). The dihedral angles formed by the benzimidazole ring system and the benzene ring of the quinazoline group are 14.28 (5) and 4.7 (3)° for the major and minor disorder components, respectively. An intra-molecular O-H⋯O hydrogen bond is present. In the crystal, mol-ecules are linked by O-H⋯N hydrogen bonds, forming chains running parallel to [10-1].

  19. Crystal structure, spectroscopic and theoretical studies on two Schiff base compounds of 2,6-dichlorobenzylidene-2,4-dichloroaniline and 2,4-dichlorobenzylidene-2,4-dichloroaniline.

    PubMed

    Soltani, Alireza; Ghari, Fereshteh; Khalaji, Aliakbar Dehno; Lemeski, E Tazikeh; Fejfarova, Karla; Dusek, Michal; Shikhi, Masoomeh

    2015-03-15

    The crystal structures of two Schiff base compounds, 2,6-dichlorobenzylidene-2,4-dichloroaniline (1) and 2,4-dichlorobenzylidene-2,4-dichloroaniline (2) have been determined from single-crystal X-ray diffraction and characterized by FT-IR and (1)H NMR spectroscopy. The electronic structures of compounds 1 and 2 in the gas phase were computed by the density functional theory (DFT) method. The obtained theoretical results were supported by the crystallographic data. In addition, theoretical configurations of the title compounds were relaxed and studied in terms of the combined analysis of HOMO-LUMO energy gap, total density of states (DOS), molecular electrostatic potential (MEP), NMR spectra and harmonic vibrational frequencies.

  20. Crystal structure, spectroscopic and theoretical studies on two Schiff base compounds of 2,6-dichlorobenzylidene-2,4-dichloroaniline and 2,4-dichlorobenzylidene-2,4-dichloroaniline

    NASA Astrophysics Data System (ADS)

    Soltani, Alireza; Ghari, Fereshteh; Khalaji, Aliakbar Dehno; Tazikeh Lemeski, E.; Fejfarova, Karla; Dusek, Michal; Shikhi, Masoomeh

    2015-03-01

    The crystal structures of two Schiff base compounds, 2,6-dichlorobenzylidene-2,4-dichloroaniline (1) and 2,4-dichlorobenzylidene-2,4-dichloroaniline (2) have been determined from single-crystal X-ray diffraction and characterized by FT-IR and 1H NMR spectroscopy. The electronic structures of compounds 1 and 2 in the gas phase were computed by the density functional theory (DFT) method. The obtained theoretical results were supported by the crystallographic data. In addition, theoretical configurations of the title compounds were relaxed and studied in terms of the combined analysis of HOMO-LUMO energy gap, total density of states (DOS), molecular electrostatic potential (MEP), NMR spectra and harmonic vibrational frequencies.

  1. Fate of 3-tert-Butyl-4-hydroxyanisole, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta(g)-2-benzopyrane and chlorpyrifos in a Conventional Wastewater Treatement Plant

    NASA Astrophysics Data System (ADS)

    Thomas, S. M.; Bodour, A.; Inniss, E. C.; Murray, K. E.

    2007-12-01

    Emerging contaminants (ECs) are a major concern in the environment, particularly those found in waters. Wastewater treatment plants (WWTPs) play a key role in reducing the concentrations in the environment because compounds may be transformed under either aerobic or anaerobic conditions or may sorb to wastewater sludges and therefore be removed from waters. If these ECs are not contained or treated then effluent discharged from the WWTP and to a receiving stream may contain hazardous levels of these contaminants. Reported here is a study of the fate of three emerging contaminants (ECs): 3-tert-Butyl-4-hydroxyanisole (BHA), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyrane (HHCB) and chlorpyrifos. Experiments were conducted on a laboratory scale by emulating conditions of a conventional WWTP in San Antonio, TX. The goal of the research was to determine general characteristics for both sorption (to wastewater sludges) and degradation. The sorption experiments were performed by exposing the sludge to a variety of initial concentration of ECs for 24 hours. After exposure these three ECs were extracted and analyzed using gas chromatography followed by flame ionization detector (GC/FID). Sorption experiments indicated that HHCB and chlorpyrifos are more hydrophobic than BHA and, therefore, would be mostly contained in the sludges. The degradation rates for these ECs were also considered for both aerobic and anaerobic conditions using different bench-scale reactor setups for 21 days. The differences between the reactor setups included volume of reactor, amount of sludge, mode of supply of nutrients and acclimatization of sludge to the ECs. One sludge was first acclimated to EC concentrations and then used in the experiment. The acclimated reactor had reaction rate constants approximately double that of the non-acclimated sludge reactor setups and followed first order reaction kinetics. Aerobic degradation occurred more readily for all three compounds

  2. Identification of the minimum PAR4 inhibitor pharmacophore and optimization of a series of 2-methoxy-6-arylimidazo[2,1-b][1,3,4]thiadiazoles.

    PubMed

    Temple, Kayla J; Duvernay, Matthew T; Maeng, Jae G; Blobaum, Anna L; Stauffer, Shaun R; Hamm, Heidi E; Lindsley, Craig W

    2016-11-15

    This letter describes the further deconstruction of the known PAR4 inhibitor chemotypes (MWs 490-525 and with high plasma protein binding) to identify a minimum PAR4 pharmacophore devoid of metabolic liabilities and improved properties. This exercise identified a greatly simplified 2-methoxy-6-arylimidazo[2,1-b][1,3,4]thiadiazole scaffold that afforded nanomolar inhibition of both activating peptide and γ-thrombin mediated PAR4 stimulation, while reducing both molecular weight and the number of hydrogen bond donors/acceptors by ∼50%. This minimum PAR4 pharmacophore, with competitive inhibition, versus non-competitive of the larger chemotypes, allows an ideal starting point to incorporate desired functional groups to engender optimal DMPK properties towards a preclinical candidate.

  3. Enzymatic synthesis and phosphorolysis of 4(2)-thioxo- and 6(5)-azapyrimidine nucleosides by E. coli nucleoside phosphorylases

    PubMed Central

    Stepchenko, Vladimir A; Miroshnikov, Anatoly I; Seela, Frank

    2016-01-01

    The trans-2-deoxyribosylation of 4-thiouracil (4SUra) and 2-thiouracil (2SUra), as well as 6-azauracil, 6-azathymine and 6-aza-2-thiothymine was studied using dG and E. coli purine nucleoside phosphorylase (PNP) for the in situ generation of 2-deoxy-α-D-ribofuranose-1-phosphate (dRib-1P) followed by its coupling with the bases catalyzed by either E. coli thymidine (TP) or uridine (UP) phosphorylases. 4SUra revealed satisfactory substrate activity for UP and, unexpectedly, complete inertness for TP; no formation of 2’-deoxy-2-thiouridine (2SUd) was observed under analogous reaction conditions in the presence of UP and TP. On the contrary, 2SU, 2SUd, 4STd and 2STd are good substrates for both UP and TP; moreover, 2SU, 4STd and 2’-deoxy-5-azacytidine (Decitabine) are substrates for PNP and the phosphorolysis of the latter is reversible. Condensation of 2SUra and 5-azacytosine with dRib-1P (Ba salt) catalyzed by the accordant UP and PNP in Tris∙HCl buffer gave 2SUd and 2’-deoxy-5-azacytidine in 27% and 15% yields, respectively. 6-Azauracil and 6-azathymine showed good substrate properties for both TP and UP, whereas only TP recognizes 2-thio-6-azathymine as a substrate. 5-Phenyl and 5-tert-butyl derivatives of 6-azauracil and its 2-thioxo derivative were tested as substrates for UP and TP, and only 5-phenyl- and 5-tert-butyl-6-azauracils displayed very low substrate activity. The role of structural peculiarities and electronic properties in the substrate recognition by E. coli nucleoside phosphorylases is discussed. PMID:28144328

  4. Enzymatic synthesis and phosphorolysis of 4(2)-thioxo- and 6(5)-azapyrimidine nucleosides by E. coli nucleoside phosphorylases.

    PubMed

    Stepchenko, Vladimir A; Miroshnikov, Anatoly I; Seela, Frank; Mikhailopulo, Igor A

    2016-01-01

    The trans-2-deoxyribosylation of 4-thiouracil ((4S)Ura) and 2-thiouracil ((2S)Ura), as well as 6-azauracil, 6-azathymine and 6-aza-2-thiothymine was studied using dG and E. coli purine nucleoside phosphorylase (PNP) for the in situ generation of 2-deoxy-α-D-ribofuranose-1-phosphate (dRib-1P) followed by its coupling with the bases catalyzed by either E. coli thymidine (TP) or uridine (UP) phosphorylases. (4S)Ura revealed satisfactory substrate activity for UP and, unexpectedly, complete inertness for TP; no formation of 2'-deoxy-2-thiouridine ((2S)Ud) was observed under analogous reaction conditions in the presence of UP and TP. On the contrary, (2S)U, (2S)Ud, (4S)Td and (2S)Td are good substrates for both UP and TP; moreover, (2S)U, (4S)Td and 2'-deoxy-5-azacytidine (Decitabine) are substrates for PNP and the phosphorolysis of the latter is reversible. Condensation of (2S)Ura and 5-azacytosine with dRib-1P (Ba salt) catalyzed by the accordant UP and PNP in Tris∙HCl buffer gave (2S)Ud and 2'-deoxy-5-azacytidine in 27% and 15% yields, respectively. 6-Azauracil and 6-azathymine showed good substrate properties for both TP and UP, whereas only TP recognizes 2-thio-6-azathymine as a substrate. 5-Phenyl and 5-tert-butyl derivatives of 6-azauracil and its 2-thioxo derivative were tested as substrates for UP and TP, and only 5-phenyl- and 5-tert-butyl-6-azauracils displayed very low substrate activity. The role of structural peculiarities and electronic properties in the substrate recognition by E. coli nucleoside phosphorylases is discussed.

  5. The dipeptidyl-peptidase-like protein DPP6 determines the unitary conductance of neuronal Kv4.2 channels.

    PubMed

    Kaulin, Yuri A; De Santiago-Castillo, José A; Rocha, Carmen A; Nadal, Marcela S; Rudy, Bernardo; Covarrubias, Manuel

    2009-03-11

    The neuronal subthreshold-operating A-type K(+) current regulates electrical excitability, spike timing, and synaptic integration and plasticity. The Kv4 channels underlying this current have been implicated in epilepsy, regulation of dopamine release, and pain plasticity. However, the unitary conductance (gamma) of neuronal somatodendritic A-type K(+) channels composed of Kv4 pore-forming subunits is larger (approximately 7.5 pS) than that of Kv4 channels expressed singly in heterologous cells (approximately 4 pS). Here, we examined the putative novel contribution of the dipeptidyl-peptidase-like protein-6 DPP6-S to the gamma of native [cerebellar granule neuron (CGN)] and reconstituted Kv4.2 channels. Coexpression of Kv4.2 proteins with DPP6-S was sufficient to match the gamma of native CGN channels; and CGN Kv4 channels from dpp6 knock-out mice yielded a gamma indistinguishable from that of Kv4.2 channels expressed singly. Moreover, suggesting electrostatic interactions, charge neutralization mutations of two N-terminal acidic residues in DPP6-S eliminated the increase in gamma. Therefore, DPP6-S, as a membrane protein extrinsic to the pore domain, is necessary and sufficient to explain a fundamental difference between native and recombinant Kv4 channels. These observations may help to understand the molecular basis of neurological disorders correlated with recently identified human mutations in the dpp6 gene.

  6. The Dipeptidyl-Peptidase-Like Protein DPP6 Determines the Unitary Conductance of Neuronal Kv4.2 Channels

    PubMed Central

    De Santiago-Castillo, José A.; Rocha, Carmen A.; Nadal, Marcela S.; Rudy, Bernardo; Covarrubias, Manuel

    2009-01-01

    The neuronal subthreshold-operating A-type K+ current regulates electrical excitability, spike timing, and synaptic integration and plasticity. The Kv4 channels underlying this current have been implicated in epilepsy, regulation of dopamine release, and pain plasticity. However, the unitary conductance (γ) of neuronal somatodendritic A-type K+ channels composed of Kv4 pore-forming subunits is larger (∼7.5 pS) than that of Kv4 channels expressed singly in heterologous cells (∼4 pS). Here, we examined the putative novel contribution of the dipeptidyl-peptidase-like protein-6 DPP6-S to the γ of native [cerebellar granule neuron (CGN)] and reconstituted Kv4.2 channels. Coexpression of Kv4.2 proteins with DPP6-S was sufficient to match the γ of native CGN channels; and CGN Kv4 channels from dpp6 knock-out mice yielded a γ indistinguishable from that of Kv4.2 channels expressed singly. Moreover, suggesting electrostatic interactions, charge neutralization mutations of two N-terminal acidic residues in DPP6-S eliminated the increase in γ. Therefore, DPP6-S, as a membrane protein extrinsic to the pore domain, is necessary and sufficient to explain a fundamental difference between native and recombinant Kv4 channels. These observations may help to understand the molecular basis of neurological disorders correlated with recently identified human mutations in the dpp6 gene. PMID:19279261

  7. Synthesis of 6-acrylamido-4-(2-[18F]fluoroanilino)quinazoline: Aprospective irreversible EGFR binding probe

    SciTech Connect

    Vasdev, Neil; Dorff, Peter N.; Gibbs, Andrew R.; Nandanan,Erathodiyil; Reid, Leanne M.; O'Neil, James P.; VanBrocklin, Henry F.

    2004-03-30

    Acrylamido-quinazolines substituted at the 6-position bindirreversibly to the intracellular ATP binding domain of the epidermalgrowth factor receptor (EGFR). A general route was developed forpreparing 6-substituted-4-anilinoquinazolines from [18F]fluoroanilinesfor evaluation as EGFR targeting agents with PET. By a cyclizationreaction, 2-[18F]fluoroaniline was reacted withN'-(2-cyano-4-nitrophenyl)-N,N-dimethylimidoformamide to produce6-nitro-4-(2-[18F]fluoroanilino)quinazoline in 27.5 percentdecay-corrected radiochemical yield. Acid mediated tin chloride reductionof the nitro group was achieved in 5 min (80 percent conversion) andsubsequent acylation with acrylic acid gave6-acrylamido-4-(2-[18F]fluoroanilino)quinazoline in 8.5 percentdecay-corrected radiochemical yield, from starting fluoride, in less than2 hours.

  8. Synthesis, characterization and anticonvulsant activity evaluation of some 1,4-dihydropyridines and 3,5-(substituted)oxycarbonyl-1,4-dihydro-2,6-dimethyl-N-[2-(4-sulfamoylphenylamino)-acetyl]-4-(substituted)pyridines.

    PubMed

    Subudhi, Bharat Bhusan; Panda, Prasanna K; Swain, Sarada P; Sarangi, Priyambada

    2009-01-01

    A series of 3,5-(substituted)oxycarbonyl-1,4-dihydro-2,6-dimethyl-4-(substituted)pyridines (1a-j) were synthesized by Hantzsch method for pyridine synthesis. Treatment with chloroacetyl chloride produced N-(2-chloroacetyl)-3,5-(substituted)oxycarbonyl-1,4-dihydro-2,6-dimethyl-4-(substituted)pyridines (2a-e), which on further treatment with sulfanilamide resulted in 3,5-(substituted)oxycarbonyl-1,4-dihydro-2,6-dimethyl-N-[2-(4-sulfamoylphenylamino)-acetyl]-4-(substituted)pyridines (3a-e). The structures has been established on the basis of spectral (IR, 1H-NMR, mass) and elemental analysis. Compounds 1a-j and 3a-e (5 mg/kg and 10 mg/kg) were evaluated for their anticonvulsant effect against pentylenetetrazole-induced convulsions with diazepam (4 mg/kg) as the reference. Compounds 3a-e exhibited significant (p<0.01) anticonvulsant activity compared to the control.

  9. Anaerobic degradation of 2,4,6-trinitrotoluene in granular activated carbon fluidized bed and batch reactors.

    PubMed

    Moteleb, M A; Suidan, M T; Kim, J; Davel, J L; Adrian, N R

    2001-01-01

    In this study, an anaerobic fluidized bed reactor (AFBR) was used to treat a synthetically produced pink water waste stream containing trinitrotoluene (TNT). The synthesized waste consisted of 95 mg/l-TNT, the main contaminant in pink water, which was to be co-metabolized with 560-mg/l ethanol. Granular activated carbon was used as the attachment medium for biological growth. TNT was reduced to a variety of compounds, mainly 2,4,6-triaminotoluene (2,4,6-TAT), 2,4-diamino-6-nitrotoluene (2,4-DA-6-NT), 2,6-diamino-4-nitrotoluene (2,6-DA-4-NT), 2-amino-4,6-dinitrotoluene (2-A-4,6-DNT), and 4-amino-2,6-dinitrotoluene (4-A-2,6-DNT). These conversions resulted through the oxidation of ethanol to carbon dioxide under anoxic conditions, or reduction to methane under methanogenic conditions. The anaerobic reactor was charged with 1.0 kg of 16 x 20 U.S. Mesh Granular Activated Carbon (GAC) and was pre-loaded with 200 g of TNT prior to the addition of the mixed seed culture. During the first three weeks of operation, ethanol was completely degraded and no methane was produced. Effluent inorganic carbon revealed stoichiometric conversion of the feed ethanol to dissolved inorganic carbon with accumulation of carbon dioxide in the headspace of the reactor. GAC extraction showed incremental reduction of the nitro groups to amino groups, with 2,4,6-TAT as the final product. After three weeks, the oxygen from the nitro groups was depleted and methane production commenced. The reproducibility of this phenomenon was confirmed by repeating the experiment in the same manner using an identical AFBR. Furthermore, serum bottle tests were conducted using TNT loading ratios of 0.2, 0.4, 0.8, 1.0 g-TNT/g-GAC as well as experiments in the absence of GAC. Similar behavior to that of the columns was observed, with degradation rates varying according to the particular condition. GAC greatly enhanced the degradation rates and the higher TNT loading resulted in slower degradation rates of ethanol.

  10. [2, 4, 6-Trichlorophenol Mineralization Promoted by Anaerobic Reductive Dechlorination of Acclimated Sludge and Extracellular Respiration Dechlorination Pathway].

    PubMed

    Song, Jia-xiu; Li, Ling; Sheng, Fan-fan; Guo, Cui-xiang; Zhang, Yong-ming; Li, Zu-yuan; Wang, Tian-li

    2015-10-01

    In anaerobic conditions, the acclimation of activated sludge was studied with sodium lactate as the electron donor and 2,4,6-trichlorophenol as the electron acceptor. Metabolic characteristics of dechlorination were the focus of this study. The result showed highly efficient dechlorination on 2, 4, 6-trichlorophenol that the conversion rate reached to 100% in 9 - 24 h when initial concentrations of sodium lactate and 2,4, 6-trichlorophenol were 20 mmol x L(-1) and 40 - 80 μmol x L(-1), respectively. The intermediate product 2,4-dichlorophenol was found in low concentration (< 4.22 μmol x L(-1)). And 4-chlorophenol and phenol were the main products. Ortho chlorophenol (2, 4, 6-trichlorophenol, 2, 4-dichlorophenol) can be converted rapidly by acclimated sludge, while the further conversion of 4-chlorophenol and phenol was limited. The residues of anaerobic metabolism were degraded by aerobic sludge, among which 4-chlorophenol (initial concentration of 33 mol x L(-1)) removal rate was up to 100% under aerobic conditions. The acclimated bacteria can rapidly transfer Fe(III) and humus (AQDS) into reductive Fe(II) and AQH2DS which indicated that the dissimilatory iron reducing bacteria was enriched in the acclimated sludge. The electron mediator [Fe(III) and AQDS] significantly accelerated the dechlorination rate. The acclimated sludge could perform extracellular respiration dechlorination with electron mediators.

  11. Synthesis and Pharmacological Characterization of C4-(Thiotriazolyl)-substituted-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylates. Identification of (1R,2S,4R,5R,6R)-2-Amino-4-(1H-1,2,4-triazol-3-ylsulfanyl)bicyclo[3.1.0]hexane-2,6-dicarboxylic Acid (LY2812223), a Highly Potent, Functionally Selective mGlu2 Receptor Agonist.

    PubMed

    Monn, James A; Prieto, Lourdes; Taboada, Lorena; Hao, Junliang; Reinhard, Matthew R; Henry, Steven S; Beadle, Christopher D; Walton, Lesley; Man, Teresa; Rudyk, Helene; Clark, Barry; Tupper, David; Baker, S Richard; Lamas, Carlos; Montero, Carlos; Marcos, Alicia; Blanco, Jaime; Bures, Mark; Clawson, David K; Atwell, Shane; Lu, Frances; Wang, Jing; Russell, Marijane; Heinz, Beverly A; Wang, Xushan; Carter, Joan H; Getman, Brian G; Catlow, John T; Swanson, Steven; Johnson, Bryan G; Shaw, David B; McKinzie, David L

    2015-09-24

    Identification of orthosteric mGlu(2/3) receptor agonists capable of discriminating between individual mGlu2 and mGlu3 subtypes has been highly challenging owing to the glutamate-site sequence homology between these proteins. Herein we detail the preparation and characterization of a series of molecules related to (1S,2S,5R,6S)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylate 1 (LY354740) bearing C4-thiotriazole substituents. On the basis of second messenger responses in cells expressing other recombinant human mGlu2/3 subtypes, a number of high potency and efficacy mGlu2 receptor agonists exhibiting low potency mGlu3 partial agonist/antagonist activity were identified. From this, (1R,2S,4R,5R,6R)-2-amino-4-(1H-1,2,4-triazol-3-ylsulfanyl)bicyclo[3.1.0]hexane-2,6-dicarboxylic acid 14a (LY2812223) was further characterized. Cocrystallization of 14a with the amino terminal domains of hmGlu2 and hmGlu3 combined with site-directed mutation studies has clarified the underlying molecular basis of this unique pharmacology. Evaluation of 14a in a rat model responsive to mGlu2 receptor activation coupled with a measure of central drug disposition provides evidence that this molecule engages and activates central mGlu2 receptors in vivo.

  12. 4-[(E)-2,6-Dichloro-benzyl-ideneamino]-3-{1-[4-(2-methyl-prop-yl)phen-yl]eth-yl}-1H-1,2,4-triazole-5(4H)-thione.

    PubMed

    Fun, Hoong-Kun; Chantrapromma, Suchada; Sujith, K V; Patil, P S; Kalluraya, B; Muralidharan, A; Dharmaprakash, S M

    2008-07-16

    In the title Schiff base compound, C(21)H(22)Cl(2)N(4)S, the triazole ring makes dihedral angles of 2.15 (11) and 87.48 (11)° with the 2,6-dichloro-phenyl and methyl-propyl-phenyl rings, respectively. Weak intra-molecular C-H⋯S and C-H⋯Cl inter-actions generate S(6) and S(5) ring motifs, respectively. In the crystal structure, centrosymmetrically related mol-ecules are linked into dimers by N-H⋯S hydrogen bonds. These dimers are arranged into sheets parallel to the ab plane and are stacked along the c axis. C-H⋯π inter-actions involving the methyl-propyl-phenyl ring and π-π inter-actions involving the dichloro-phenyl ring [centroid-centroid distance = 3.5865 (3) Å] are also observed.

  13. Growth process of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers

    SciTech Connect

    Zhu Chengcai; Nai Xueying; Zhu Donghai; Guo Fengqin; Zhang Yongxing; Li Wu

    2013-01-15

    The reactions occurred and growth process in the preparation of copper aluminum borate (Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17}) whiskers based on flux method (Al{sub 2}(SO{sub 4}){sub 3}/CuSO{sub 4}/H{sub 3}BO{sub 3} as raw materials, K{sub 2}SO{sub 4} as flux) were investigated. The thermogravimetric and differential scanning calorimetry analysis (TG-DSC), inductively coupled plasma atomic emission spectrum analysis (ICP-AES) and X-ray diffraction analysis (XRD) results of reactants mixture quenched at various temperatures and phase diagrams of K{sub 2}SO{sub 4}-Al{sub 2}(SO{sub 4}){sub 3} system and B{sub 2}O{sub 3}-Al{sub 2}O{sub 3} system showed that the reaction process proceeds through three steps: the formation and decomposition of two different kinds of potassium aluminum sulfate (K{sub 3}Al(SO{sub 4}){sub 3} and KAl(SO{sub 4}){sub 2}); the formation of aluminum borate (Al{sub 4}B{sub 2}O{sub 9}) and decomposition of copper sulfate (CuSO{sub 4}) and boric acid (H{sub 3}BO{sub 3}); growth and formation of copper aluminum borate (Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17}) whiskers. The scanning electron microscopy (SEM) analysis results indicated that morphology in growth of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. - Graphical abstract: The morphology in growth of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. Highlights: Black-Right-Pointing-Pointer Reaction process in the preparation of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers was researched systematically. Black-Right-Pointing-Pointer Crystal growth mechanism of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} whiskers was proposed by theory and experiments. Black-Right-Pointing-Pointer Properties of Cu{sub 2}Al{sub 6}B{sub 4}O{sub 17} were analyzed by instruments, such as TG-DSC, ICP-AES, XRD and SEM.

  14. Sediment-mediated reduction of 2,4,6-trinitrotoluene and fate of the resulting aromatic (poly)amines

    SciTech Connect

    Elovitz, M.S. ); Weber, E.J. )

    1999-08-01

    2,4,6-Trinitrotoluene is a major surface and subsurface contaminant found at numerous munitions production and storage facilities. The reductive transformation of 2,4,6-trinitrotoluene (TNT) to aromatic (poly)amines and the consequent fate of these products were studied in anaerobic and aerobic sediment-water systems. Reduction of TNT was rapid under both anaerobic and aerobic conditions. Nitro-reduction was regioselective, leading to the preferential formation of 4-amino-2,6 dinitrotoluene (4-ADNT) and 2,4-diamino-6 nitrotoluene (2,4-DANT). Subsequent sorption of 2,4-DANT was rapid under aerobic conditions and resulted in nearly complete, irreversible retention by the sediment phase. Under anaerobic conditions, the rapidly formed 2,4-DANT displayed little affinity for the sediment phase. Instead, 2,4 DANT was further transformed to products that remained in the aqueous phase. Sorption studies in nontransforming sediments indicated increased irreversible sorption with replacement of nitro groups with amino groups. Covalent binding of the DANTs was partially inhibited under anoxic conditions, but sorption of TNT and the ADNTs was unaffected by changes in redox conditions.

  15. Bioremediation of 2,4,6-trinitrotoluene by bacterial nitroreductase expressing transgenic aspen.

    PubMed

    Van Dillewijn, Pieter; Couselo, José L; Corredoira, Elena; Delgado, Antonio; Wittich, Rolf-Michael; Ballester, Antonio; Ramos, Juan L

    2008-10-01

    Trees belonging to the genus Populus are often used for phytoremediation due to their deep root formation, fast growth and high transpiration rates. Here, we study the capacity of transgenic hybrid aspen (Populus tremula x tremuloides var. Etropole) which expresses the bacterial nitroreductase gene, pnrA, to tolerate and take-up greater amounts of the toxic and recalcitrant explosive, 2,4,6-trinitrotoluene (TNT) from contaminated waters and soil. Transgenic aspen tolerate up to 57 mg TNT/L in hydroponic media and more than 1000 mg TNT/ kg soil, whereas the parental aspen could not endure in hydroponic culture with more than 11 mg TNT/L or soil with more than 500 mg TNT/kg. Likewise, the phytotoxicological limit for transgenic plants to a constant concentration of TNT was 20 mg TNT/L while wild-type plants only tolerated 10 mg TNT/L. Transgenic plants also showed improved uptake of TNT over wild-type plants when the original TNT concentration was above 35 mg TNT/L in liquid media or 750 mg TNT/kg in soil. Assays with 13C-labeled TNT show rapid adsorption of TNT to the root surface followed by a slower entrance rate into the plant. Most of the 13C-carbon from the labeled TNT taken up bythe plant (> 95%) remains in the root with little translocation to the stem. Altogether, transgenic aspen expressing pnrA are highly interesting for phytoremediation applications on contaminated soil and underground aquifers.

  16. Photochemistry of 1 and 2-(2-methylphenyl)-1,6-heptadiene. [4a-methyl-1,2,3,4,4a,9,10,10a-octahydrophenanthrene

    SciTech Connect

    Barrows, R.D.; Hornback, J.M.

    1982-01-01

    In an attempt to synthesize partially saturated phenanthrene derivatives by an intramolecular Diels-Alder reaction between a photochemically produced o-xylylene (diene) and a tethered dienophile, it was found that 1 and 2 underwent a photochemically allowed (2 + 2) cycloaddition. Irradiation of 1 gave 6-(2-methylphenyl)bicyclo(3.2.0)heptane in 86% yield. Upon irradiation of 2, a benzvalene rearrangement of 2 first took place, producing the meta isomer 2-(3-methylphenyl)-1,6-heptadiene, followed by a (2 + 2) photocycloaddition giving 1-(3-methylphenyl)bicyclo(3.2.0)heptane in 15% yield. Direct irradiation of 2-(3-methylphenyl)-1,6-heptadiene gave the same bicyclo derivative as 2 in 34% yield. Examination of the fluorescence spectra of 1 and 2 in comparison with 1-(2-methylphenyl)propene and 2-(2-methylphenyl)-1-butene, respectively, has shown that 1 may be biased toward (2 + 2) cycloaddition where 2 is not biased toward (2 + 2) photocycloization. Attempts to produce 4a-methyl-1,2,3,4,4a,9,10,10a-octahydrophenanthrene by an intramolecular Diels-Alder reaction of the o-xylylene produced by irradiation of 3 will also be described.

  17. 4-Hy­droxy-6-methyl­pyridin-2(1H)-one

    PubMed Central

    Reyes, Héctor; Aguirre, Gerardo; Chávez, Daniel

    2013-01-01

    In the crystal structure of the title compound, C6H7NO2, N—H⋯O and O—H⋯O hydrogen bonds link the mol­ecules, forming a zigzag array along [001] and a layer structure parallel to the ab plane. PMID:24098221

  18. 1-(2,6-Diisopropyl-phen-oxy)-4-phenyl-phthalazine.

    PubMed

    Tong, Bihai; Mei, Qunying

    2012-08-01

    In the title mol-ecule, C(26)H(26)N(2)O, the phenyl and phen-oxy 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 inter-actions.

  19. Volumetric Properties of the Mixture Oxolan-2-one C4H6O2 + C4H10O Butan-1-ol (VMSD1511, LB4906_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Oxolan-2-one C4H6O2 + C4H10O Butan-1-ol (VMSD1511, LB4906_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  20. Volumetric Properties of the Mixture Methanol CH4O + C4H6O2 Oxolan-2-one (VMSD1511, LB4904_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Methanol CH4O + C4H6O2 Oxolan-2-one (VMSD1511, LB4904_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  1. 3,6-Bis(2-pyridyl)di-1,2,4-triazolo[3,4-a:4',3'-c]phthalazine.

    PubMed

    Chang, Wen-Fu; Wen, Yuh-Sheng; Liu, Ling-Kang

    2004-09-01

    The title compound, C20H12N8, (I), has been prepared by the reaction of 1,4-dihydrazinophthalazine and pyridine-2-carboxaldehyde, followed by an oxidative cyclization by treatment with bromine. In the solid state, the molecules of (I) are discrete, comprising a fused and twisted four-ring system with an overall helical appearance. The distance between the two intramolecular pyridyl N atoms is 3.075 (2) A, this short contact distance suggesting a pi-pi interaction.

  2. 2,6-Dihy-droxy-4-oxo-2-(pyridin-1-ium-3-yl)-4H-1,3,2-benzodioxaborinin-2-ide 0.67-hydrate.

    PubMed

    Garcia-Grajeda, Blanca A; Höpfl, Herbert; Guerrero-Alvarez, Jorge A; Campos-Gaxiola, José J; Cruz-Enríquez, Adriana

    2014-04-01

    The asymmetric unit of the title compound, C12H10BNO5·0.67H2O, contains three independent pyridinylboronic acid esters adopting zwitterionic forms and two water mol-ecules. The six-membered heterocyclic rings in the boronic esters have half-chair conformations and the deviations of the B atoms from the boronate mean planes range from 0.456 (3) to 0.657 (3) Å. All of the B atoms have tetra-hedral coordination environments, with B-O and B-C bond lengths of 1.446 (4)-1.539 (3) and 1.590 (5)-1.609 (5) Å, respectively. In the crystal, the ester and water mol-ecules are linked into a three-dimensional network by a large number of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds. The crystal packing is further accomplished by π-π inter-actions, with centroid-centroid distances of 3.621 (4)-3.787 (4) Å.

  3. Pseudomonas aeruginosa strain MA01 aerobically metabolizes the aminodinitrotoluenes produced by 2,4,6-trinitrotoluene nitro group reduction.

    PubMed

    Alvarez, M A; Kitts, C L; Botsford, J L; Unkefer, P J

    1995-11-01

    Many microbes reduce the nitro substituents of 2,4,6-trinitrotoluene (TNT), producing aminodinitrotoluenes (ADNTs). These compounds are recalcitrant to further breakdown and are acutely toxic. In a search for organisms capable of metabolizing ADNTs, a bacterial strain was isolated for the ability to use 2-aminobenzoate (anthranilate) as sole C-source. This isolate, Pseudomonas aeruginosa MA01, metabolized TNT by first reducing one nitro group to form either 2-amino-4,6-dinitrotoluene (2ADNT) or 4-amino-2,6-dinitrotoluene (4ADNT). However, strain MA01 was distinct from other TNT-reducing organisms in that it transformed these compounds into highly polar metabolites through an O2-dependent process. Strain MA01 was able to cometabolize TNT, 2ADNT, and 4ADNT in the presence of a variety of carbon and energy sources. During aerobic cometabolism with succinate, 45% of uniformly ring-labeled [14C]TNT was transformed to highly polar compounds. Aerobic cometabolism of purified [14C]2ADNT and [14C]4ADNT with succinate as C-source produced similar amounts of these polar metabolites. During O2-limited cometabolism with succinate as C-source and nitrate as electron acceptor, less than 8% of the [14C]TNT was transformed to polar metabolites. Purified 2,6-diamino-4-nitrotoluene was not metabolized, and while 2,4-diamino-6-nitrotoluene was acetylated, the product (N-acetyl-2,4-diamino-6-nitrotoluene) was not further metabolized. Therefore, strain MA01 metabolized TNT by oxidation of the ADNTs and not by reduction the remaining nitro groups on the ADNTs.

  4. Fluorine-containing heterocycles: synthesis and some reactions of new 3-amino-2-functionalized-6-(2'-thienyl)-4-trifluoromethylthieno [2,3-b]pyridines.

    PubMed

    Abdel-Monem, M I; Mohamed, O S; Bakhite, E A

    2001-01-01

    3-Cyano-6-(2'-thienyl)-4-trifluoromethylpyridine-2(1H)-thione (2) was prepared and reacted with chloroacetone or phenacyl bromide to yield the 2-acetyl or benzoyl-3-amino-6-(2'-thienyl)-4-trifluoromethylthieno[2,3-b]pyridines (3a, b). In contrast, the reaction of 2 with chloroacetamide or its N-aryl derivatives gave the corresponding 2-carbamoylmethyl thiopyridines 4a-c. Upon treatment of these educts with K2CO3 or C2H5ONa in ethanol, they underwent intramolecular Thorpe-Ziegler cyclization to afford 3-amino-2-carbamoyl-6-(2'-thienyl)-4-trifluoromethyl-thieno[2,3-b]pyridine (5a) and its N-aryl analogs 5b, c. Compounds 5a-c underwent some reactions to yield new pyrido[3',2':4,5]thieno[3,2-d]pyrimidines and pyrido[3',2':4,5]thieno[3,2-d][1,2,3] triazines.

  5. Genomic and proteomic characterization of Gordonia sp. NB4-1Y in relation to 6 : 2 fluorotelomer sulfonate biodegradation.

    PubMed

    Van Hamme, Jonathan D; Bottos, Eric M; Bilbey, Nicholas J; Brewer, Sharon E

    2013-08-01

    Gordonia sp. strain NB4-1Y was isolated from vermicompost using bis-(3-pentafluorophenylpropyl)-sulfide as the sole added sulfur source and was found to have a broad capacity for metabolizing organosulfur compounds. NB4-1Y is closely related to G. desulfuricans and was found to metabolize 6 : 2 fluorotelomer sulfonate (6 : 2 FTS) to 5 : 3 fluorotelomer acid (5 : 3 acid) via 6 : 2 fluorotelomer acid (6 : 2 FTCA), 6 : 2 unsaturated fluorotelomer acid (6 : 2 FTUCA) and 5 : 3 unsaturated fluorotelomer acid (5 : 3 Uacid). Given that the molecular and biochemical basis for the microbial metabolism of poly- and per-fluorinated compounds has yet to be examined, we undertook to investigate 6 : 2 FTS metabolism in NB4-1Y. To this end, a whole-genome shotgun sequence was prepared and two-dimensional differential in-gel electrophoresis was used to compare proteomes of MgSO4- and 6 : 2 FTS-grown cells. Of the three putative alkanesulfonate monooxygenases, four nitrilotriacetate monooxygenases and one taurine dioxygenase located in the draft genome, two nitrilotriacetate monooxygenases were differentially expressed in the presence of 6 : 2 FTS. It is hypothesized that these two enzymes may be responsible for 6 : 2 FTS desulfonation. In addition, a differentially expressed putative double bond reductase may be involved in the reduction of 5 : 3 Uacid to 5 : 3 acid. Other proteins differentially expressed during 6 : 2 FTS metabolism included a sulfate ABC transporter ATP-binding protein and two alkyl hydroperoxide reductases. This work establishes a foundation for future studies on the molecular biology and biochemistry of poly- and per-fluorinated compound metabolism in bacteria.

  6. Reactions of Fe+ and FeO+ with C2H2, C2H4, and C2H6: temperature-dependent kinetics.

    PubMed

    Ard, Shaun G; Melko, Joshua J; Fournier, Joseph A; Shuman, Nicholas S; Viggiano, Albert A

    2013-10-10

    We present the first temperature-dependent rate constants and branching ratios for the reactions of Fe(+) and FeO(+) with C2H2, C2H4, and C2H6 from 170 to 700 K. Fe(+) is observed to react only by association with the three hydrocarbons, with temperature dependencies of T(-2) to T(-3). FeO(+) reacts with C2H2 and C2H4 at the collision rate over the temperature range, and their respective product branchings show similar temperature dependences. In contrast, the reaction with ethane is collisional at 170 K but varies as T(-0.5), while the product branching remains essentially flat with temperature. These variations in reactivity are discussed in terms of the published reactive potential surfaces. The effectiveness of Fe(+) as an oxygen-transfer catalyst toward the three hydrocarbons is also discussed.

  7. 40 CFR 721.5281 - 2-Naphthalenesulfonic acid, 3-[[4-[(2,4-dimethyl-6-sulfophenyl)azo]-2-methoxy-5-methylphenyl]azo...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 2-Naphthalenesulfonic acid, 3- -2-methoxy-5-methylphenyl]azo]-4-hydroxy-7-(phenylamino)-, sodium salt, compd. With 2,2â²,2â³-nitrilotris (9CI). 721.5281 Section 721.5281 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT...

  8. 40 CFR 721.5281 - 2-Naphthalenesulfonic acid, 3-[[4-[(2,4-dimethyl-6-sulfophenyl)azo]-2-methoxy-5-methylphenyl]azo...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 2-Naphthalenesulfonic acid, 3- -2-methoxy-5-methylphenyl]azo]-4-hydroxy-7-(phenylamino)-, sodium salt, compd. With 2,2â²,2â³-nitrilotris (9CI). 721.5281 Section 721.5281 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT...

  9. 40 CFR 721.5281 - 2-Naphthalenesulfonic acid, 3-[[4-[(2,4-dimethyl-6-sulfophenyl)azo]-2-methoxy-5-methylphenyl]azo...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 2-Naphthalenesulfonic acid, 3- -2-methoxy-5-methylphenyl]azo]-4-hydroxy-7-(phenylamino)-, sodium salt, compd. With 2,2â²,2â³-nitrilotris (9CI). 721.5281 Section 721.5281 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT...

  10. 40 CFR 721.5281 - 2-Naphthalenesulfonic acid, 3-[[4-[(2,4-dimethyl-6-sulfophenyl)azo]-2-methoxy-5-methylphenyl]azo...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Naphthalenesulfonic acid, 3- -2-methoxy-5-methylphenyl]azo]-4-hydroxy-7-(phenylamino)-, sodium salt, compd. With 2,2â²,2â³-nitrilotris (9CI). 721.5281 Section 721.5281 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT...

  11. 40 CFR 721.5281 - 2-Naphthalenesulfonic acid, 3-[[4-[(2,4-dimethyl-6-sulfophenyl)azo]-2-methoxy-5-methylphenyl]azo...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2-Naphthalenesulfonic acid, 3- -2-methoxy-5-methylphenyl]azo]-4-hydroxy-7-(phenylamino)-, sodium salt, compd. With 2,2â²,2â³-nitrilotris (9CI). 721.5281 Section 721.5281 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT...

  12. Photoluminescence properties of a novel red emitting Ba10F2(PO4)6:Eu3+ phosphor

    NASA Astrophysics Data System (ADS)

    Peng, You-shun; Shi, Wei-wei; Han, Cong-lin; Kang, Yan-yan; Wang, Yan-su; Zhang, Zhi-wei

    2015-06-01

    A novel red-emitting phosphor Ba10F2(PO4)6:Eu3+ is synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirms the phase formation of Ba10F2(PO4)6:Eu3+ materials. The photoluminescence excitation (PLE) and emission (PL) spectra, the concentration dependence of the emission intensity, decay curves and Commission International de I'Eclairage (CIE) of the phosphors are investigated. It is observed that Ba10F2(PO4)6:Eu3+ phosphors exhibit two dominating bands situated at 591 and 616 nm, originating from the 5D0 → 7F1 and 5D0 → 7F2 transition of the Eu3+ ion, respectively. The decay time is also determined for various concentrations of Eu3+ in Ba10F2(PO4)6:Eu3+. Crystal lattice, PL spectra and decay time analysis indicate there exist two isolated Eu3+ crystallography sites in Ba10F2(PO4)6. The calculated color coordinates lie in the red region. Therefore, Ba10F2(PO4)6:Eu3+ phosphors may be good candidates for red components in near-UV (NUV) white LEDs.

  13. Synthesis, conformational preferences and antimicrobial evaluation of N-piperazinoacetyl-r-2,c-6-diphenylpiperidin-4-ones

    NASA Astrophysics Data System (ADS)

    Akila, A.; Jeganathan, P.; Ponnuswamy, S.

    2016-09-01

    Five new N-piperazinoacetyl-r-2,c-6-diphenylpiperidin-4-ones 11-15 have been synthesized and characterized using IR, 1H, 13C, DEPT & 2D NMR and mass spectral studies. The NMR spectral data indicate that the N-piperazinoacetyl-r-2,c-6-diphenylpiperidin-4-ones 11-15 prefer to exist in an equilibrium between B1 and B2 conformations. Furthermore, the antibacterial and antifungal studies were carried out. The results show that the piperazinoacetyl piperidin-4-ones 11-15 exhibit good activity against the selected bacterial and fungal strains.

  14. Cascade synthesis of polyoxygenated 6H,11H-[2]benzopyrano-[4,3-c][1]benzopyran-11-ones.

    PubMed

    Naumov, Mikael I; Sutirin, Sergey A; Shavyrin, Andrey S; Ganina, Olga G; Beletskaya, Irina P; Bourgarel-Rey, Véronique; Combes, Sébastien; Finet, Jean-Pierre; Fedorov, Alexey Yu

    2007-04-27

    2-(methoxymethoxymethyl)aryllead triacetates, obtained in situ from the corresponding arylboronic acids, reacted with 4-hydroxycoumarins, leading to 3-(2-methoxymethoxymethyl)aryl-4-hydroxycoumarin derivatives in good to high yields. These compounds underwent a cascade sequence of reactions, deprotection-halogenation-annulation, to afford polyoxygenated tetracyclic 6H,11H-[2]benzopyrano-[4,3-c] [1]benzopyran-11-ones in good yields. Some compounds showed a moderate cytotoxicity against human epithelial mammary HBL100 cells.

  15. Structure and optical properties of KLa9(GeO4)6O2 and KLa8.37Eu0.63(GeO4)6O2

    NASA Astrophysics Data System (ADS)

    Lipina, Olga A.; Surat, Ludmila L.; Tyutyunnik, Alexander P.; Enyashin, Andrey N.; Chufarov, Alexander Yu.; Zubkov, Vladimir G.

    2017-01-01

    New KLa9(GeO4)6O2 and KLa8.37Eu0.63(GeO4)6O2 germanates with the apatite structure type (space group P63/m, Z = 1) have been synthesized by the sol-gel method using ethylenediaminetetraacetic acid as a precursor and characterized by powder X-ray diffraction, scanning electron microscopy and diffuse reflectance spectroscopy. Density functional theory calculations reveal that KLa9(GeO4)6O2 is a direct bandgap material, and near-UV excitation leads to the electronic transitions from the O2p- orbitals to the Lad- and K4s- states. Photoluminescence measurements of the Eu3+-doped sample indicate emission in the visible spectral range corresponding to the characteristic transitions from the excited 5D0 and 5D1 levels in europium ion.

  16. Fluorescence of poly[2,6-(4-phenylquinoline)] and its blends

    NASA Astrophysics Data System (ADS)

    Lin, Hung-Sheng

    Optical absorption measurements and photoluminescence spectroscopy have been carried out on a class of nitrogen-containing pi-conjugated polymers which can be used as active materials in light emitting diodes. In this dissertation, Poly [2,6-(4-phenylquinoline)] (PPQ) was used as a model system to demonstrate that optical properties could be manipulated by inducing morphology changes in various PPQ-blends as well as by solvent interactions with the pi-conjugated backbone of the PPQ. It is shown that by controlling the preparation conditions, adding small molecules, and/or blending with other interactive polymers, the of the absorption and/or emission could be altered. Furthermore, it was found that both doping and chain packing may have important effects on the energy gap between the ground state and the excited state. There are two major peaks in the UV absorption spectrum of the PPQ. One peak is assigned to the phenyl group side chain, whereas the other one reflects the PPQ backbone, whose absorption has been illustrated to be dependent on experimental conditions. The position of the major photoluminescence emission peak was found to be influenced by (1) the nature of the solvent and the doping agents used, (2) different processing methods, and (3) blending with photo-inactive polymers such as Poly(vinyl alcohol) (PVA), Poly(ethylene oxide) (PEO), Poly(acrylic acid)(PAA), Sulfonic polystyrene (SPS), etc. These factors singly or in combination contribute to the shifting of the emission peak. In a polymer blend, the strength of the enthalpic interaction between its components determines the spatial separation of the polymers, which results in different morphologies in the blend, and in turn, different optical properties of the blend. Since the emission from a blend depends on its morphological dispersion, optical studies of polymer blends first involve control of morphologies in these blends. The morphologies of polymer blends have been studied by using Scanning

  17. 2-r-(4-Chloro­phen­yl)-6-c-phenyl-3,4,5,6-tetra­hydro-2H-thio­pyran-4-one 1-oxide

    PubMed Central

    Thiruvalluvar, A.; Balamurugan, S.; Butcher, R. J.; Pandiarajan, K.; Devanathan, D.

    2008-01-01

    The thio­pyran unit of the title mol­ecule, C17H15ClO2S, is in chair form. A crystallographic mirror plane bis­ects the mol­ecule, passing through the O=S and the opposite C=O atoms of the central ring, with statistical disorder of the Cl atom. The geometry around the S atom is tetra­hedral and the carbonyl C is planar. The 4-chloro­phenyl group at the 2 position and the phenyl ring at the 6 position have equatorial orientations. Inter­molecular C—H⋯O and C—H⋯Cl hydrogen bonds are found in the crystal structure. In addition, there is a short O⋯C inter­molecular contact [2.970 (5) Å]. PMID:21581339

  18. Assembly of tetra, di and mononuclear molecular cadmium phosphonates using 2,4,6-triisopropylphenylphosponic acid and ancillary ligands.

    PubMed

    Chandrasekhar, Vadapalli; Sasikumar, Palani; Boomishankar, Ramamoorthy

    2008-10-14

    The reaction of ArPO(3)H(2) (Ar = 2,4,6-iPr(3)-C(6)H(2)) with Cd(CH(3)COO)(2).2H(2)O using various co-ligands such as methanol, dimethylformamide (DMF) and 3,5-dimethylpyrazole (DMPZH) resulted in the formation of tetranuclear assemblies [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(CH(3)OH)(4)].3(CH(3)OH) (1), [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(DMF)(4)].3(DMF) (2) and [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(DMF)(2)(DMPZH)(2)].2(DMF).2(H(2)O) (3). In all of these compounds the tetranuclear cadmium array, containing two five-coordinate and two six-coordinate cadmium atoms, is held together by two mu(4) capping [ArPO(3)](2-) and four anisobidentate mu(2) [ArPO(2)(OH)](-) ligands. Each cadmium atom is bound to an additional ancillary ligand. The reaction of ArPO(3)H(2) with Cd(CH(3)COO)(2).2H(2)O in the presence of the chelating ligand 2,2'-bipyridine (bipy) leads to the exclusive formation of the dinuclear assembly [Cd(2)(ArPO(3)H)(4)(bipy)(2)].(CH(3)OH)(H(2)O) (4). The latter contains an eight-membered Cd(2)P(2)O(4) inorganic ring formed as a result of the bridging coordination action of two anisobidentate mu(2) [ArPO(2)(OH)](-) ligands. Each cadmium atom is bound by one chelating bipy and one monodentate [ArPO(2)(OH)](-) ligands. Use of four equivalents of 3,5-dimethylpyrazole leads to the formation of the mononuclear derivative [Cd(ArPO(3)H)(2)(DMPZH)(4)] (5). The molecular structure of the latter comprises of a central cadmium atom surrounded by six monodentate ligands. Four of these are neutral pyrazole ligands that occupy the equatorial plane; the remaining two are anionic phosphinate ligands which are present trans to each other. The thermal analysis of 1 and 4 reveals that the char residue obtained at 600 degrees C consists predominantly of Cd(2)P(2)O(7).

  19. Quasi-two-dimensional S =1/2 magnetism of Cu[ C6H2 (COO)4][ C2H5NH3 ] 2

    NASA Astrophysics Data System (ADS)

    Nath, R.; Padmanabhan, M.; Baby, S.; Thirumurugan, A.; Ehlers, D.; Hemmida, M.; Krug von Nidda, H.-A.; Tsirlin, A. A.

    2015-02-01

    We report structural and magnetic properties of the spin-1/2 quantum antiferromagnet Cu[ C6H2(COO) 4 ][ C2H5NH3 ] 2 by means of single-crystal x-ray diffraction, magnetization, heat capacity, and electron-spin-resonance (ESR) measurements on polycrystalline samples, as well as band-structure calculations. The triclinic crystal structure of this compound features CuO4 plaquette units connected into a two-dimensional framework through anions of the pyromellitic acid [ C6H2(COO) 4 ]4 -. The ethylamine cations [ C2H5NH3]+ are located between the layers and act as spacers. Magnetic susceptibility and heat capacity measurements establish a quasi-two-dimensional, weakly anisotropic, and nonfrustrated spin-1/2 square lattice with the ratio of the couplings Ja/Jc≃0.7 along the a and c directions, respectively. No clear signatures of the long-range magnetic order are seen in thermodynamic measurements down to 1.8 K. However, the gradual broadening of the ESR line suggests that magnetic ordering occurs at lower temperatures. Leading magnetic couplings are mediated by the organic anion of the pyromellitic acid and exhibit a nontrivial dependence on the Cu-Cu distance, with the stronger coupling between those Cu atoms that are farther apart.

  20. High-spin intermediates of the photolysis of 2,4,6-triazido-3-chloro-5-fluoropyridine

    PubMed Central

    Korchagin, Denis V; Neuhaus, Patrik; Sander, Wolfram

    2013-01-01

    Summary In contrast to theoretical expectations, the photolysis of 2,4,6-triazido-3-chloro-5-fluoropyridine in argon at 5 K gives rise to EPR peaks of just two triplet mononitrenes, two quintet dinitrenes, and a septet trinitrene. EPR spectral simulations in combination with DFT calculations show that observable nitrenes can be assigned to triplet 2,4-diazido-3-chloro-5-fluoropyridyl-6-nitrene (D T = 1.026 cm−1, E T = 0), triplet 2,6-diazido-3-chloro-5-fluoropyridyl-4-nitrene (D T = 1.122 cm−1, E T = 0.0018 cm−1), quintet 4-azido-3-chloro-5-fluoropyridyl-2,6-dinitrene (D Q = 0.215 cm−1, E Q = 0.0545 cm−1), quintet 2-azido-3-chloro-5-fluoropyridyl-4,6-dinitrene (D Q = 0.209 cm−1, E Q = 0.039 cm−1) and septet 3-chloro-5-fluoropyridyl-2,4,6-trinitrene (D S = −0.1021 cm−1, E S = −0.0034 cm−1). Preferential photodissociation of the azido groups located in ortho-positions to the fluorine atom of pyridines is associated with strong π-conjugation of these groups with the pyridine ring. On photoexcitation, such azido groups are more efficiently involved in reorganization of the molecular electronic system and more easily adopt geometries of the locally excited predissociation states. PMID:23766785

  1. Synthesis, crystal structures and characterization of four coordination polymers based on 5-amino-2,4,6-triiodoisophthalic acid

    SciTech Connect

    Zhang Koulin; Chang Yan; Zhang Jingbo; Yuan Limin; Deng Ye; Diao Guowang; Ng, Seik Weng

    2011-05-15

    One homochiral 1D coordination polymer [Cu(ATIBDC)(2,2'-bipy)].3H{sub 2}O.CH{sub 3}OH (1) and three achiral 1D coordination polymers: [Cd(ATIBDC)(2,2'-bipy)(H{sub 2}O)].3H{sub 2}O (2), [Cd(ATIBDC)(phen)(H{sub 2}O)].4H{sub 2}O (3), and [Mn(ATIBDC)(phen){sub 2}].5H{sub 2}O (4) have been synthesized and characterized (H{sub 2}ATIBDC=5-amino-2,4,6-triiodoisophthalic acid, 2,2'-bipy=2,2'-bipyridine, and phen=1,10-phenanthroline). Extended high dimensional network architectures are further constructed with the help of weak secondary interactions, such as hydrogen bonding, aromatic stacking, and halogen bonding (C-I..{pi} and C-I...N/O). Complex 1 crystallizes in the monoclinic system with chiral space group P2(1) and exhibits a right-handed 2{sub 1} helical chain structure. The homochirality of 1 was confirmed by CD spectrum. Interestingly, two new configurations of decameric water cluster are found in 3 and 4. The acyclic tetrameric cluster (H{sub 2}O){sub 3}(CH{sub 3}OH) in 1 and (H{sub 2}O){sub 4} in 2 array into highly ordered helical infinite chains. Thermal stabilities of all the complexes have been studied. Solid state fluorescent properties of the Cd(II) complexes have been explored. -- Graphical abstract: The synthesis, crystal structures and characterization of one 1D homochiral coordination polymer and three achiral 1D coordination polymers with 5-amino-2,4,6-triiodoisophthalic acid (H{sub 2}ATIBDC) are reported. Display Omitted highlights: > Four 1D coordination polymers with 5-amino-2,4,6-triiodoisophthalate are reported. > The halogen bonds play important roles in the supramolecular assembly. > Solid state fluorescent properties of the Cd(II) complexes are explored.

  2. 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.

  3. Oxidation and alpha-case formation in Ti–6Al–2Sn–4Zr–2Mo alloy

    SciTech Connect

    Gaddam, Raghuveer; Sefer, Birhan; Pederson, Robert; Antti, Marta-Lena

    2015-01-15

    Isothermal heat treatments in ambient air were performed on wrought Ti–6Al–2Sn–4Zr–2Mo (Ti-6242) material at 500, 593 and 700°C for times up to 500 h. In the presence of oxygen at elevated temperatures simultaneous reactions occurred in Ti-6242 alloy, which resulted in the formation of an oxide scale and a layer with higher oxygen concentration (termed as alpha-case). Total weight gain analysis showed that there was a transition in the oxidation kinetics. At 500°C, the oxidation kinetics obeyed a cubic relationship up to 200 h and thereafter changed to parabolic at prolonged exposure times. At 593°C, it followed a parabolic relationship. After heat treatment at 700°C, the oxidation obeyed a parabolic relationship up to 200 h and thereafter changed to linear at prolonged exposure times. The observed transition is believed to be due to the differences observed in the oxide scale. The activation energy for parabolic oxidation was estimated to be 157 kJ/mol. In addition, alpha-case layer was evaluated using optical microscope, electron probe micro-analyser and microhardness tester. The thickness of the alpha-case layer was found to be a function of temperature and time, increasing proportionally, and following a parabolic relationship. The activation energy for the formation of alpha-case layer was estimated to be 153 kJ/mol. - Highlights: • Transition in oxidation kinetics was observed in Ti–6Al–2Sn–4Zr–2Mo alloy in the temperature range 500–700°C. • The activation energy for parabolic oxidation and for alpha-case formation is about 157 kJ/mol and 153 kJ/mol. • Thickness of alpha-case layer estimated by optical microscopy and electron probe microanalysis is comparable.

  4. Concerning the electronic coupling of MoMo quadruple bonds linked by 4,4'-azodibenzoate and comparison with t2g 6-Ru(II) centers by 4,4'-azodiphenylcyanamido ligands.

    PubMed

    Chisholm, Malcolm H; D'Acchioli, Jason S; Hadad, Christopher M; Patmore, Nathan J

    2006-12-25

    From the reactions between Mo2(O2CtBu)4 and each of terephthalic acid and 4,4'-azodibenzoic acid, the compounds [Mo2(O2CtBu)3]2(mu-O2CC6H4CO2) (1) and [Mo2(O2CtBu)3]2(mu-O2CC6H4N2C6H4CO2) (2) have been made and characterized by spectroscopic and electrochemical methods. Their electronic structures have been examined by computations employing density functional theory on model compounds where HCO2 substitutes for tBuCO2. On the basis of these studies, the two Mo2 units are shown to be only weakly coupled and the mixed-valence ions 1+ and 2+ to be valence-trapped and Class II and I, respectively, on the Robin-Day classification scheme for mixed-valence compounds. These results are compared to t2g6-Ru centers linked by 1,4-dicyanamidobenzene and azo-4,4'-diphenylcyanamido bridges for which the mixed-valence ions [Ru-bridge-Ru]5+ have been previously classified as fully delocalized, Class III [Crutchley et al. Inorg. Chem. 2001, 40, 1189; Inorg. Chem. 2004, 43, 1770], and on the basis of results described herein, it is proposed that the latter complex ion is more likely a mixed-valence organic radical where the bridge is oxidized and not the Ru(2+) centers.

  5. X-Ray Powder Diffraction Data for Na8(AlSiO4)6(ReO4)2

    SciTech Connect

    McCready, David E.; Mattigod, Shas V.; Young, James S.; McGrail, B. Peter

    2004-01-31

    X-ray powder diffraction data for a new zeolite, Na8(AlSiO4)6(ReO4)2, are reported. Rietveld refinement shows this compound adopts the primitive cubic structure of sodalite (Space Group , #218) with a = 9.1528 (1) Å. The calculated value of the reference intensity ratio (RIR, or I/Ic) is 7.54. The experimental density (Dm) is 2.98 ± 0.10 g/cm3, in agreement with the calculated density (Dx) of 3.029 g/cm3. Chemical analysis of Na8(AlSiO4)6(ReO4)2 gives its composition as 11.7 ± 1.6 wt % Na; 10.7 ± 0.2 wt % Al; 11.6 ± 0.9 wt % Si; 30.6 ± 1.2 wt % Re, which compares favorably with the theoretical composition of 13.2 wt % Na, 11.6 wt% Al, 12.1 wt% Si; 26.6 wt % Re. In addition, scanning electron microscopy reveals a doubly terminated trapezohedral crystal morphology for Na8(AlSiO4)6(ReO4)2, which is typical of sodalite.

  6. Design, synthesis, and preclinical evaluation of new 5,6- (or 6,7-) disubstituted-2-(fluorophenyl)quinolin-4-one derivatives as potent antitumor agents.

    PubMed

    Chou, Li-Chen; Tsai, Meng-Tung; Hsu, Mei-Hua; Wang, Sheng-Hung; Way, Tzong-Der; Huang, Chi-Hung; Lin, Hui-Yi; Qian, Keduo; Dong, Yizhou; Lee, Kuo-Hsiung; Huang, Li-Jiau; Kuo, Sheng-Chu

    2010-11-25

    Our previous exploration of 2-phenylquinolin-4-ones (2-PQs) has led to an anticancer drug candidate 2-(2-fluorophenyl)-6,7-methylenedioxyquinolin-4-one monosodium phosphate (CHM-1-P-Na). In order to develop additional new drug candidates, novel 2-PQs were designed, synthesized, and evaluated for cytotoxic activity. Most analogues, including 1b, 2a,b, 3a,b, 4a,b, and 5a,b, exhibited significant inhibitory activity (IC(50) of 0.03-8.2 μM) against all tested tumor cell lines. As one of the most potent analogue, 2-(3-fluorophenyl)-5-hydroxy-6-methoxyquinolin-4-one (3b) selectively inhibited 14 out of 60 cancer cell lines in a National Cancer Institute (NCI) evaluation. Preliminary mechanism of action study suggested that 3b had a significant effect on the tyrosine autophosphorylation of insulin-like growth factor-1 receptor (IGF-1R). Safety pharmacology profiling of 3b showed no significant effect on normal biological functions of most enzymes tested. Furthermore, sodium 2-(3-fluorophenyl)-6-methoxy-4-oxo-1,4-dihydroquinolin-5-yl phosphate (15), the monophosphate of 3b, exceeded the activity of doxorubicin and was comparable to CHM-1-P-Na in a Hep3B xenograft nude mice model. In summary, 15 is a promising clinical candidate and is currently under preclinical study.

  7. 2,3,4,5,6-Penta­fluoro-trans-cinnamic acid

    PubMed Central

    Navarrete, Angélica; Somanathan, Ratnasamy; Aguirre, Gerardo

    2013-01-01

    The title compound, C9H3F5O2, crystallizes as O—H⋯O hydrogen-bonded carb­oxy­lic acid dimers that, together with C—H⋯F inter­actions and O⋯F [2.8065 (13) and 2.9628 (13) Å] and F⋯F [2.6665 (11), 2.7049 (12) and 2.7314 (12) Å] contacts, form a sheet-like structure. The sheets are stacked via short π–π inter­actions [centroid–centroid distance = 4.3198 (11) Å]. An intra­molecular C—H⋯F inter­action is also observed. PMID:24098209

  8. 4-Hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester derivatives as potent anti-tumor agents.

    PubMed

    Hayakawa, Ichiro; Shioya, Rieko; Agatsuma, Toshinori; Furukawa, Hidehiko; Naruto, Shunji; Sugano, Yuichi

    2004-01-19

    Based on the structure of 4-hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester (1), which exhibits selective cytotoxicity against a tumorigenic cell line, (2,4-dimethoxyphenyl)-(4-hydroxy-3-methyl-6-phenylbenzofuran-2-yl)-methanone (18m) was designed and synthesized as a biologically stable derivative containing no ester group. Although the potency of 18m was almost the same as our initial hit compound 1, 18m is expected to last longer in the human body as an anticancer agent.

  9. Synthesis and structure-active relationship of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline anticonvulsants.

    PubMed

    Gitto, Rosaria; De Luca, Laura; Ferro, Stefania; Agnello, Stefano; Russo, Emilio; De Sarro, Giovanbattista; Chimirri, Alba

    2010-12-01

    We have previously disclosed that some 6,7-dimethoxyisoquinoline derivatives are able to produce anticonvulsant effects in different animal models of epilepsy. Following these studies this paper describes the synthesis of a small series of new 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines strictly related to previously reported analogues. This novel series of isoquinolines was designed on the basis of well defined structure-active relationship (SAR) information already acquired for this class of anticonvulsant agents. The pharmacological effects of the new synthesized compounds were evaluated against audiogenic seizures in Dilute Brown non-Agouti (DBA/2) mice. The preliminary pharmacological screening led to the identification of a new active molecule the 2-acetyl-1-(4'-methylphenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (6d) that displayed significant anticonvulsant activity. Computational studies helped to rationalize these obtained pharmacological results.

  10. One-dimensional decavanadate chains in the crystal structure of Rb4[Na(H2O)6][HV10O28]·4H2O.

    PubMed

    Yakubovich, Olga V; Steele, Ian M; Yakovleva, Ekaterina V; Dimitrova, Olga V

    2015-06-01

    New decavanadate minerals, the products of the leaching or metasomatic processes, are possible in nature via Na/Rb removal/inclusion reactions. As part of our search for novel vanadate phases with varying functionalities, a new phase, tetrarubidium hexaaquasodium hydrogen decavanadate tetrahydrate, Rb4[Na(H2O)6][HV10O28]·4H2O, has been synthesized by the hydrothermal technique at 553 K. Ten shared edges of V-centred octahedra form monoprotonated decavanadate cages, which are joined together via hydrogen bonds into one-dimensional chains parallel to the [101] direction. Within these chains, H atoms are sandwiched between neighbouring polyanions. Na and Rb atoms and H2O molecules occupy interstices flanked by the anionic chains providing additional crosslinking in the structure. This compound is the second decavanadate with P2/n symmetry. Structural relationships among protonated and deprotonated decavanadates with inorganic cations, including minerals of the pascoite group, are discussed.

  11. X-ray crystallography of methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4 H-pyran)-3-carboxylate

    NASA Astrophysics Data System (ADS)

    Sharma, Suresh; Banerjee, Bubun; Brahmachari, Goutam; Kant, Rajni; Gupta, Vivek K.

    2016-12-01

    The organic carbonitrile namely methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4 H-pyran)- 3-carboxylate is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst and its crystal structure is determined by X-ray technique. The crystals are monoclinic, sp. gr. C2/ c, a = 12.3069(8) Å, b = 9.7023(7) Å, c = 24.812(2) Å, β = 94.862(6)°, Z = 8. The dihedral angle between pyran and phenyl rings is 87.8(1)°; the pyran ring is almost planar The dihedral angle between the mean planes of phenyl ring and nitro group is 44.4(2)°. The crystal structure is stabilized by N-H···N and N-H···O hydrogen bonds. In addition, C-H···π interactions are also observed in the crystal structure.

  12. X-ray and Synchrotron Diffraction Studies of 2-(Pyridin-2-yl)-1,10- Phenanthroline in the Role of Ligand for Two Copper Polymorphs or Hydrogen bonded with 2,2,6,6-Tetramethyl-4-oxopiperidinium Hexafluorophosphate

    SciTech Connect

    Krause, Jeanette A.; Zhao, Daoli; Chatterjee, Sayandev; Yeung, Bonnie M.; Connick, William B.; Collins, Sibrina N.

    2013-12-01

    Different extended packing motifs of dichloro-[2-(pyridin-2-yl)-1,10-phenanthroline]copper(II), CuCl2 (C17H11N3Cl2) are obtained depending on the crystallization conditions. A triclinic form (I) is obtained from dimethylformamide-diethyl ether or methanol whereas crystallization from dimethylformamide-water yields a monoclinic form (II). In each case, the CuII center is in a 5-coordinate, distorted square-pyramidal geometry. The extended packing for both forms can be described as a highly-offset π stacking arrangement with interlayer distances of 3.674 (3) and 3.679 (3) Å for (I) and (II), respectively. The reaction of diprotonated Pt(tmpip2NCN)Cl (tmpip2NCN = 2,6-bis(2,2,6,6-tetramethylpiperidylmethyl)- benzyl) with AgPF6 under acidic conditions followed by the addition of 2-(pyridin-2-yl)-1,10-phenanthroline, results in a hydrogen bonded co-crystal, 2,2,6,6-tetramethyl-4-oxopiperidinium hexafluorophosphate- 2-(pyridin-2-yl)-1,10-phenanthroline (1/1),C9H18NO+.PF6-.C17H11N3.(III). The extended packing maximizes π-π interactions in a parallel, faceto-face arrangement with an interlayer stacking distance of 3.4960 (14) Å.

  13. The 5 f r arrow 6 d absorption spectrum of Pa sup 4+ /Cs sub 2 ZrCl sub 6

    SciTech Connect

    Edelstein, N.; Kot, W.K. ); Krupa, J. )

    1992-01-01

    The 5{ital f}{sup 1}{r arrow}6{ital d}{sup 1} absorption spectrum of {sup 231}Pa{sup 4+} diluted in a single crystal of Cs{sub 2}ZrCl{sub 6} has been measured at 4.2 K. Three bands corresponding to the 6{ital d}({Gamma}{sub 8{ital g}}, {Gamma}{sub 7{ital g}}, and {Gamma}{sup {prime}}{sub 8{ital g}} ) levels are assigned. Extensive vibronic structure has been observed for the lowest 5{ital f}{r arrow}6{ital d} transition and this structure is compared to that recently reported for the 6{ital d}{sup 1}{r arrow}5{ital f}{sup 1} emission spectra in the same system.

  14. Acute toxicity of cadmium, copper, zinc, ammonia, 3,3 prime -dichlorobenzidine, 2,6-dichloro-4-nitroaniline, methylene chloride, and 2,4,6-trichlorophenol to juvenile grass shrimp and killifish

    SciTech Connect

    Burton, D.T.; Fisher, D.J. )

    1990-05-01

    The acute toxicity of several compounds was investigated while performing a toxicity evaluation of a complex chemical effluent. The tests were conducted for one or more of the following reasons: (1) data were not available for the chemical; (2) data were not available for the species; or (3) data were not available for the juvenile life stage of the species. Forty-eight hour acute toxicity tests were run on juvenile grass shrimp (Palaemonetes pugio) and juvenile killifish (Fundulus heteroclitus) exposed to the following compounds: cadmium, copper, zinc, ammonia, 3,3{prime}-dichlorobenzidine, 2,6-dichloro-4-nitroaniline, methylene chloride (dichloromethane) and 2,4,6-trichlorophenol.

  15. Nqrs Data for C10H4CrD6N2O3S [C9CrD6O3·CH4N2S] (Subst. No. 1205)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C10H4CrD6N2O3S [C9CrD6O3·CH4N2S] (Subst. No. 1205)

  16. Synthesis and crystal structure of Ru III-supported tungstoantimonate [Sb 2W 20Ru III2(H 2O) 2(dmso) 6O 68] 4-

    NASA Astrophysics Data System (ADS)

    Bi, Li-Hua; Li, Bao; Bi, Shuai; Wu, Li-Xin

    2009-06-01

    The first Ru III-supported tungstoantimonate [Ru II(bpy) 3] 2[Sb 2W 20Ru III2(H 2O) 2(dmso) 6O 68]·3dmso (bpy=bi-pyridine) ( 1a) has been successfully isolated as [Ru(bpy) 3] 2+ (Rubpy) salt by routine synthetic reaction in mixed solutions with dmso and water. Single-crystal X-ray analysis was carried out on 1a, which crystallizes in the triclinic system space group P-1 with a=16.804 (6), b=16.988 (6), c=17.666 (6) Å, α=107.397 (13)°, β=106.883 (13)°, γ=103.616 (12)°. V=4309 (3) Å 3, Z=1 with R1=0.0773. The compound 1a reveals the following features: (1) Rubpy is firstly used as an alternative ruthenium-source for the synthesis of Ru-substituted heteropolytungstate; (2) the structure of 1a consists of four Ru III-O-S(CH 3) 2 and two W-O-S(CH 3) 2 bonds resulting in an assembly with C2 symmetry; (3) the Ru III ions are linked to two dmso groups via two Ru III-O-S(CH 3) 2 bonds, which represents the other dmso-coordination mode to Ru III in POM chemistry. The cyclic voltammetry studies of 1a in dmso/H 2SO 4 (3/1 v/v) at pH 2.5 medium using the glassy carbon electrode as a working electrode show the respective electrochemical behaviors of the W-centers and the Ru-centers within 1a, which could be separated clearly. In addition, the compound 1a exhibits photoluminescence arising from π*- t2g ligand-to-metal transition of Rubpy.

  17. Constraints on Asian and European sources of methane from CH4-C2H6-CO correlations in Asian outflow

    NASA Astrophysics Data System (ADS)

    Xiao, Yaping; Jacob, Daniel J.; Wang, James S.; Logan, Jennifer A.; Palmer, Paul I.; Suntharalingam, Parvadha; Yantosca, Robert M.; Sachse, Glen W.; Blake, Donald R.; Streets, David G.

    2004-08-01

    Aircraft observations of Asian outflow from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the NW Pacific (March and April 2001) show large CH4 enhancements relative to background, as well as strong CH4-C2H6-CO correlations that provide signatures of regional sources. We apply a global chemical transport model simulation of the CH4-C2H6-CO system for the TRACE-P period to interpret these observations in terms of CH4 sources and to explore in particular the unique constraints from the CH4-C2H6-CO correlations. We use as a priori a global CH4 source inventory constrained with National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) surface observations [Wang et al., 2004]. We find that the observed CH4 concentration enhancements and CH4-C2H6-CO correlations in Asian outflow in TRACE-P are determined mainly by anthropogenic emissions from China and Eurasia (defined here as Europe and eastern Russia), with only little contribution from tropical sources (wetlands and biomass burning). The a priori inventory overestimates the observed CH4 enhancements and shows regionally variable biases for the CH4/C2H6 slope. The CH4/CO slopes are simulated without significant bias. Matching both the observed CH4 enhancements and the CH4-C2H6-CO slopes in Asian outflow requires increasing the east Asian anthropogenic source of CH4, and decreasing the Eurasian anthropogenic source, by at least 30% for both. The need to increase the east Asian source is driven by the underestimate of the CH4/C2H6 slope in boundary layer Chinese outflow. The Streets et al. [2003] anthropogenic emission inventory for east Asia fits this constraint by increasing CH4 emissions from that region by 40% relative to the a priori, largely because of higher livestock and landfill source estimates. Eurasian sources (mostly European) then need to be reduced by 30-50% from the a priori value of 68 Tg yr-1. The decrease of

  18. 4,4'-, 5,5'-, and 6,6'-dimethyl-2,2'-bipyridyls: The structures, phase transitions, vibrations, and methyl group tunneling of their complexes with chloranilic acid

    NASA Astrophysics Data System (ADS)

    Bator, G.; Sawka-Dobrowolska, W.; Sobczyk, L.; Grech, E.; Nowicka-Scheibe, J.; Pawlukojć, A.; Wuttke, J.; Baran, J.; Owczarek, M.

    2011-07-01

    The crystal and molecular structures of 4,4'- and 6,6'-dimethyl-2,2'-bipyridyl complexes with 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (chloranilic acid, CLA) have been determined and compared with those of the complex with the 5,5'-derivative, which is known to possess interesting antiferroelectric properties. In the crystalline state, all three compounds form hydrogen bonded chains with N+-H...O- and O-H...N bridges on both sides of the bipyridyl constituent. The comparison of three derivatives indicates that the N+-H...O- hydrogen bonds are shortest for the 5,5'-dimethyl complex. The 4,4'- and 6,6'-derivatives do not show any ferroelectric feature. The 6,6'-one is, however, characterized by a continuous phase transition, revealed in the differential scanning calorimetry, dilatometric, and dielectric characteristics. The tunneling splitting measured by neutron backscattering in the energy range ±30 μeV for the neat dimethyl bipyridyls and their complexes with CLA indicates that the different splittings are primarily due to the crystal packing effect and that charge transfer between interacting compounds plays only a minor role.

  19. Ligand field density functional theory calculation of the 4f24f15d1 transitions in the quantum cutter Cs2KYF6:Pr3+.

    PubMed

    Ramanantoanina, Harry; Urland, Werner; Cimpoesu, Fanica; Daul, Claude

    2013-09-07

    Herein we present a Ligand Field Density Functional Theory (LFDFT) based methodology for the analysis of the 4f(n)→ 4f(n-1)5d(1) transitions in rare earth compounds and apply it for the characterization of the 4f(2)→ 4f(1)5d(1) transitions in the quantum cutter Cs2KYF6:Pr(3+) with the elpasolite structure type. The methodological advances are relevant for the analysis and prospection of materials acting as phosphors in light-emitting diodes. The positions of the zero-phonon energy corresponding to the states of the electron configurations 4f(2) and 4f(1)5d(1) are calculated, where the praseodymium ion may occupy either the Cs(+)-, K(+)- or the Y(3+)-site, and are compared with available experimental data. The theoretical results show that the occupation of the three undistorted sites allows a quantum-cutting process. However size effects due to the difference between the ionic radii of Pr(3+) and K(+) as well as Cs(+) lead to the distortion of the K(+)- and the Cs(+)-site, which finally exclude these sites for quantum-cutting. A detailed discussion about the origin of this distortion is also described.

  20. Ba0.4Rb0.6Mn2As2: A prototype half-metallic ferromagnet

    DOE PAGES

    Pandey, Abhishek; Johnston, D. C.

    2015-11-02

    Half-metallic ferromagnetism (FM) in single-crystal Ba0.39(1)Rb0.61(1)Mn2As2 below its Curie temperature TC = 103(2) K is reported. The magnetization M versus applied magnetic field H isotherm data at 1.8 K show complete polarization of the itinerant doped-hole magnetic moments that are introduced by substituting Rb for Ba. Here, the material exhibits extremely soft FM, with unobservably small remanent magnetization and coercive field. Surprisingly, and contrary to typical itinerant FMs, the M(H) data follow the Arrott-plot paradigm that is based on a mean-field theory of local-moment FMs. The in-plane electrical resistivity data are fitted well by an activated-T2 expression for T ≤more » TC, whereas the data sharply deviate from this model for T > TC. Hence the activated-T2 resistivity model is an excellent diagnostic for determining the onset of half-metallic FM in this compound, which in turn demonstrates the presence of a strong correlation between the electronic transport and magnetic properties of the material. Together with previous data on 40% hole-doped Ba0.6K0.4Mn2As2, these measurements establish 61%-doped Ba0.39Rb0.61Mn2As2 as a prototype for a class of half-metallic ferromagnets in which all the itinerant carriers in the material are ferromagnetic.« less