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Sample records for coii tetra penta

  1. Tris(bis(trimethylsilyl)amido)uranium: Compounds with tri-, tetra-, and penta-valent uranium

    SciTech Connect

    Stewart, J.L.

    1988-04-01

    This trivalent uranium compound, serves as a precursor to new tri-, tetra-, and penta-valent uranium species. The geometry about the U atom is pyramidal. Lewis-base coordination compounds of U(N(SiMe/sub 3/)/sub 2/)/sub 3/ with a one-to-one- ratio of Lewis base to uranium were isolated with pyridine, 4-dimethylamino-pyridine, 2,6-Me/sub 2/-C/sub 6/H/sub 3/NC, and TPO. Two-to-one coordination compounds were obtained with t-butylnitrile and t-butylisocyanide. Compounds with more sterically demanding bases could not be isolated. The expected decrease in U-N(SiMe/sub 3/)/sub 2/ bond length with increase in oxidation state is not observed. Reaction of ClU(N(SiMe/sub 3/)/sub 2/)/sub 3/and Li(NH(p-tolyl)) yields the uranium (IV) dimer, U/sub 2/(N(SiMe/sub 3/)/sub 2/)/sub 4/(..mu..-N(p-tolyl))/sub 2/. Reaction with 2,4,6-triemethylaniline produces a dimer. Analogous substitution products could not be obtained with aniline or p-toluidine. t-Bu/sub 3/CO/sup /minus//, t-Bu/sub 2/CHO/sup /minus//, and t-Bu/sub 3/SiO/sup /minus// are used to synthesize new tetravalent, mononuclear uranium compounds. Reaction of ClU(tritox)/sub 3/ with alkyllithium reagents leads to isolation of RU(tritox)/sub 3/. The reaction of U(ditox)/sub 4/ with MeLi affords the addition product U(ditox)/sub 4/(Me)Li, whose crystal structure is described. Preparation of uranium silox compounds is reported. 97 refs., 26 figs., 39 tabs.

  2. Tetra­kis(μ-penta­fluoro­benzoato-κ2 O:O′)bis­[(tetra­hydro­furan-κO)molybdenum(II)

    PubMed Central

    Han, Li-Juan

    2011-01-01

    In the asymmetric unit of the title compound, [Mo2(C7F5O2)4(C4H8O)2], two independent half-mol­ecules are present, which are completed by a crystallographically imposed center of inversion between the individual Mo atoms. In each mol­ecule, four penta­fluoro­benzoate anions bridge the quadruply bonded Mo2 4+ unit that is, in addition, axially coordinated by two O atoms of tetra­hydro­furan (THF) mol­ecules. In the two independent mol­ecules, the mean Mo—Mo bond length is 2.110 Å. Since the THF mol­ecules are equally disordered over two sets of sites, there are four different Mo—O distances in both half-mol­ecules with an overall mean of 2.542 Å. A zigzag chain is formed by π–π stacking inter­actions between penta­fluoro­phenyl rings, indicated by a centroid–centroid distance of 3.7054 (11) Å and a centroid-to-plane distance of 3.4169 (3) Å. The extension of the unit gives a three-dimensional network structure with the THF mol­ecules located in the voids. PMID:22058882

  3. Dicarbon­yl(hexa­methyl­ene-1,3,5,7-tetra­mine-κN 1)(η5-penta­methyl­cyclo­penta­dien­yl)iron(II) tetra­fluoridoborate

    PubMed Central

    M’thiruaine, Cyprian M.; Friedrich, Holger B.; Changamu, Evans O.; Fernandes, Manuel A.

    2012-01-01

    In the title compound, [Fe(C10H15)(C6H12N4)(CO)2]BF4, the arrangement around the FeII atom corresponds to a three-legged piano stool. The penta­methyl­cyclo­penta­dienyl (Cp*) ligand occupies three coordination sites, while two CO ligands and one N atom of the hexa­methyl­ene­tetra­mine ligand occupy the remaining coordination sites, completing a pseudo-octahedral geometry. Both the complex cation and the BF4 − anion reside on crystallographic mirror planes. The Fe—N bond length is 2.069 (2) and the Fe—Cp*(centroid) distance is 1.7452 (3) Å. PMID:22807762

  4. The First Pilot Comprehensive Evaluation of the Outcomes of Different Types of Robotic Surgeries in the Different Surgical Departments: The Penta, Tetra and Trifecta Achievements in Robotic Surgeries

    PubMed Central

    Sejima, Takehiro; Morizane, Shuichi; Fujiwara, Kazunori; Ashida, Keigo; Saito, Hiroaki; Taniguchi, Yuji; Nakamura, Hiroshige; Takenaka, Atsushi

    2016-01-01

    Background To ensure safe performance in robotic surgery, the Minimal Invasive Surgery Center (MISC) is composed of the anesthesiology department, five surgery departments and co-medical staff in our institution. The objective of this study was to evaluate the outcomes of different types of robotic surgeries for cancer treatment (n = 326) from different surgery departments in the MISC. Methods The outcomes of robot-assisted radical prostatectomy (RARP), partial nephrectomy (RAPN), transoral robotic surgery (TORS) for pharyngeal cancer, and robotic surgery for lung, gastric and rectal cancer were evaluated using the similar concept of pentafecta in RARP. Results The pentafecta rates of RARP and robotic surgery for rectal cancer were 33.3 and 56.5%, respectively. The tetrafecta rates of RARP (excluding potency evaluation from pentafecta) and TORS were 48.4 and 57.1%, respectively. The trifecta rates of RAPN, robotic surgeries for lung and gastric cancer were 75.9, 74.2 and 84.2%, respectively. The failure of tetrafecta in RARP achievement was significantly associated with high risk than with low risk according to National Comprehensive Cancer Network classification. Conclusion This is the world’s first comprehensive evaluation of different types of robotic surgeries for cancer treatment in the constitutional framework of an academic institution. MISC, which provides the constitutional framework of an academic institution, is providing immeasurable benefits in terms of robotic surgery quality, and it may ultimately lead to high penta-, tetra-, and trifecta rates for robotic surgeries for cancer treatment in all surgical departments. PMID:27493484

  5. Trichlorido-1κ2 Cl,2κCl-(2,6-dimethyl­phenolato-2κO)-μ-oxido-bis{1,2(η5)-2,3,4,5-tetra­methyl-1-[4-(trimethyl­silyl)phen­yl]cyclo­penta­dien­yl}dititanium(IV)

    PubMed Central

    Luo, Xuyang; Wu, Qiaolin; Mu, Ying

    2011-01-01

    The title dinuclear titanocene, [Ti2(C8H9O)(C18H25Si)2Cl3O], contains one Ti atom tetra­hedrally coordinated by two Cl atoms, a bridging O atom and the substituted cyclo­penta­dienyl ligand, and another Ti atom tetra­hedrally coordinated by a Cl atom, a bridging O atom, the 2,6-dimethyl­phenolate ligand and the substituted cyclo­penta­dienyl ligand. The bridging O atom lies on a twofold rotation axis. PMID:22064795

  6. Synthesis, DNA-binding, DNA-photonuclease profiling and antimicrobial activity of novel tetra-aza macrocyclic Ni(II), Co(II) and Cu(II) complexes constrained by thiadiazole

    NASA Astrophysics Data System (ADS)

    Vinay Kumar, B.; Bhojya Naik, H. S.; Girija, D.; Sharath, N.; Pradeepa, S. M.; Joy Hoskeri, H.; Prabhakara, M. C.

    A new tetra-aza macrocyclic ligand, L (C24H16N12O2S4) and its complexes of type, [MLCl2] and [CuL]Cl2 (where M = Ni(II), Co(II); L = N,N'-(benzene-1,3-diyldi-1,3,4-thiadiazole-5,2-diyl)bis{2-[(5-benzene-1,3-diyl-1,3,4-thiadiazol-2-yl)amino]acetamide}) were synthesized and characterized by the spectral and analytical techniques. An octahedral geometry has been proposed for Ni(II) and Co(II) complexes while Cu(II) complex exhibit a square planar geometry. All the synthesized metal complexes were screened for their in vitro antimicrobial activity against selected species of pathogenic bacteria and fungi. The binding property of the complexes with CT-DNA was studied by absorption spectral analysis, followed by viscosity measurement and thermal denaturation studies. The photo induced cleavage studies revealed that the complexes possess photonuclease property against pUC19 DNA under UV-visible irradiation.

  7. Bis[1,2-bis­(meth­oxy­carbon­yl)ethene-1,2-dithiol­ato-κ2 S,S′]bis­(η5-penta­methyl­cyclo­penta­dien­yl)tetra-μ3-sulfido-tetra­iron(4 Fe–Fe) hexa­fluoridophosphate

    PubMed Central

    Inomata, Shinji; Ito, Shohei; Takase, Tsugiko

    2013-01-01

    The asymmetric unit of the title compound, [Fe4(C6H6O4S2)2(C10H15)2S4]PF6, contains two different complex cations and two PF6 − anions. The two complex cations have similar conformations with the butterfly-like Fe4S4 core surrounded by two penta­methyl­cyclo­penta­dienyl ligands and the S atoms of two dithiol­ate ligands. In each Fe4S4 core, there are four short Fe—Fe and two long Fe⋯Fe contacts, suggesting bonding and non-bonding inter­actions, respectively. The Fe—S distances range from 2.1287 (13) to 2.2706 (16) Å for one and from 2.1233 (13) to 2.2650 (16) Å for the other Fe4S4 core. The Fe—S distances involving the dithiol­ate ligands are in a more narrow range [2.1764 (16)–2.1874 (13) Å for one and 2.1743 (14)–2.1779 (16) Å for the other cation]. There are no significant inter­actions between cations and anions. PMID:23634019

  8. Crystal structure of μ-oxido-1,1'κ(2) O:O-bis{tetra-μ-oxido-1:2κ(2) O:O;1:3κ(2) O:O;2:3κ(4) O:O-tris[1,2,3(η(5))-penta-methyl-cyclo-penta-dien-yl]-trianglo-trititanium(IV)}.

    PubMed

    Pérez-Redondo, Adrián; Martín, Avelino

    2015-04-01

    The title polynuclear organometallic titanium(IV) oxide, [{Ti3(η(5)-C5Me5)3(μ-O)4}2(μ-O)], exhibits two Ti3O4 cores bridged by an O atom located on a twofold axis. All metal centres present the typical three-legged piano-stool coordination environment, where one site is occupied by a penta-methyl-cyclo-penta-dienyl ligand linked in an η(5)-coordination fashion, while three bridging O atoms fill the other three sites. PMID:26029420

  9. Penta-zirconium copper tribismuth.

    PubMed

    Balinska, Agnieszka; Tarasiuk, Ivan; Pavlyuk, Volodymyr

    2013-01-01

    Penta-zirconium copper tribismuth, Zr5CuBi3, crystallizes in the hexa-gonal Hf5CuSn3 structure type. The asymmetric unit contains two Zr sites (site symmetries 3.2 and m2m), one Cu site (site symmetry 3.m) and one Bi site (site symmetry m2m). The environment of the Bi atoms is a tetra-gonal anti-prism with one added atom and a coordination number (CN) of 9. The polyhedron around the Zr1 atom is a defective cubo-octa-hedron with CN = 11. The bicapped hexa-gonal anti-prism (CN = 14) is typical for Zr2 atoms. The Cu atom is enclosed in a eight-vertex polyhedron (octa-hedron with two centered faces). The metallic type of bonding was indicated by an analysis of the inter-atomic distances and electronic structure calculation data.

  10. catena-Poly[[tetra­kis­(μ-penta­fluoro­benzoato-κ2 O:O′)dimolybdenum(II)]-μ-4,4′-bipyridine-κ2 N:N′

    PubMed Central

    Han, Li-Juan

    2011-01-01

    In the title compound, [Mo2(C7F5O2)4(C10H8N2)]n, the mol­ecule forms a paddle-wheel-type structure. Each Mo2 4+ unit is equatorially coordinated by four pentafluoro­benzoate groups, while the axial positions are occupied by two 4,4′-bipyridine mol­ecules. The Mo—Mo bond length of 2.1227 (4) Å is representative of a dimolybdenum quadruple bond. An infinite linear chain parallel to [110] is formed by the Mo2 4+ unit coordinating axially to the two N atoms of the 4,4′-bipyridine ligand [Mo—N = 2.594 (2) Å]. The crystal packing shows mol­ecules linked together into a three-dimensional network via Mo—N coordination inter­actions and weak π–π stacking inter­actions between perfluoro­phenyl rings [centroid–centroid distance = 3.7280 (3) Å and centroid-to-plane distance = 3.6103 (12) Å between two penta­fluoro­phenyl rings]. PMID:22058859

  11. Crystal structure of a dinuclear Co(II) complex with bridging fluoride ligands: di-μ-fluorido-bis-{tris-[(6-methyl-pyridin-2-yl)meth-yl]amine}-dicobalt(II) bis-(tetra-fluorido-borate).

    PubMed

    Inomata, Masataka; Suenaga, Yusaku

    2014-11-01

    Reaction of Co(BF4)2·6H2O with tris-[(6-methyl-pyridin-2-yl)meth-yl]amiine in methanol results in a fluoride abstraction from BF4 (-), yielding the unexpected title compound, [Co2F2(C21H24N4)2](BF4)2. The complex cation consists of two inversion-related [Co(C21H24N4)](2+) moieties bridged by a pair of fluoride ligands. The Co(II) cation is six-coordinated in a distorted octa-hedral geometry and forms a +II high-spin state. In the crystal, the complex cation and the BF4 (-) anion are connected by C-H⋯F hydrogen bonds, forming a three-dimensional network. An intra-molecular C-H⋯F hydrogen bond is also observed. PMID:25484774

  12. Penta-europium dicadmium penta-anti-monide oxide, Eu(5)Cd(2)Sb(5)O.

    PubMed

    Saparov, Bayrammurad; Bobev, Svilen

    2011-01-15

    The title compound, Eu(5)Cd(2)Sb(5)O adopts the Ba(5)Cd(2)Sb(5)F-type structure (Pearson symbol oC52), which contains nine crystallographically unique sites in the asymmetric unit, all on special positions. One Eu, two Sb, and the Cd atom have site symmetry m..; two other Eu, the third Sb and the O atom have site symmetry m2m; the remaining Eu atom has 2/m.. symmetry. Eu atoms fill penta-gonal channels built from corner-sharing CdSb(4) tetra-hedra. The isolated O atom, i.e., an oxide ion O(2-), is located in a distorted tetra-hedral cavity formed by four Eu cations.

  13. Crystal structure of μ-oxido-1,1′κ2 O:O-bis{tetra-μ-oxido-1:2κ2 O:O;1:3κ2 O:O;2:3κ4 O:O-tris[1,2,3(η5)-penta­methyl­cyclo­penta­dien­yl]-trianglo-trititanium(IV)}

    PubMed Central

    Pérez-Redondo, Adrián; Martín, Avelino

    2015-01-01

    The title polynuclear organometallic titanium(IV) oxide, [{Ti3(η5-C5Me5)3(μ-O)4}2(μ-O)], exhibits two Ti3O4 cores bridged by an O atom located on a twofold axis. All metal centres present the typical three-legged piano-stool coordination environment, where one site is occupied by a penta­methyl­cyclo­penta­dienyl ligand linked in an η5-coordination fashion, while three bridging O atoms fill the other three sites. PMID:26029420

  14. Iridoids from Pentas lanceolata.

    PubMed

    Schripsema, Jan; Caprini, Geisa Paulino; van der Heijden, Rob; Bino, Raoul; de Vos, Ric; Dagnino, Denise

    2007-09-01

    From the aerial parts of Pentas lanceolata, belonging to the family Rubiaceae, a series of iridoid glucosides was isolated by preparative HPLC. Seven iridoid glucosides were identified. Besides asperuloside and asperulosidic acid, characteristic iridoids for Rubiaceae, five new iridoids were isolated, namely, tudoside (1), 13R-epi-gaertneroside (2), 13R-epi-epoxygaertneroside (3), and a mixture of E-uenfoside (4) and Z-uenfoside (5). Further, it was shown that the compound reported as citrifolinin B (6) is in fact the same as tudoside and should be revised. Also, the configuration of the previously reported iridoids gaertneroside and epoxygaertneroside has been elucidated.

  15. (1'S,12'R,13'S,17'S)-15',15'-Dimethyl-1,2-dihydro-11',14',16',18'-tetra-oxa-7'-aza-spiro-[indole-3,8'-penta-cyclo-[10.6.0.0(2,9).0(3,7).0(13,17)]octa-deca-ne]-2,10'-dione.

    PubMed

    Sabari, V; Ponnusamy, R; Prasanna, R; Raghunathan, R; Aravindhan, S

    2013-04-01

    In the title compound, C22H24N2O6, the indole ring has a twist conformation and the tetra-hydro-2H-pyran-2-one ring a half-chair conformation. One of the pyrrolidine rings adopts an envelope conformation on the N atom, while the other has a twist conformation; the 'butterfly' angle between their mean planes is 62.98 (11)°. The dioxolane ring adopts a twist conformation and the tetra-hydro-furan ring has an envelope conformation on the C atom in the fused tetra-hydro-2H-pyran-2-one ring adjacent to the O atom of the tetra-hydro-furan ring. The 'butterfly' angle between the mean planes of these two five-membered rings is 69.14 (10)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains along the a axis.

  16. Orally administered DTPA penta-ethyl ester for the decorporation of inhaled 241Am

    PubMed Central

    Sueda, Katsuhiko; Sadgrove, Matthew P.; Huckle, James E.; Leed, Marina G. D.; Weber, Waylon M.; Doyle-Eisele, Melanie; Guilmette, Raymond A.; Jay, Michael

    2014-01-01

    Diethylenetriaminepentaacetic acid (DTPA) is an effective decorporation agent to facilitate the elimination of radionuclides from the body, but its permeability-limited oral bioavailability limits its utility in mass-casualty emergencies. To overcome this limitation, a prodrug strategy using the penta-ethyl ester form of DTPA is under investigation. Pharmacokinetic and biodistribution studies were conducted in rats by orally administering [14C]DTPA penta-ethyl ester, and this prodrug and its hydrolysis products were analyzed as a single entity. Compared to a previous reporting of intravenously administered DTPA, the oral administration of this prodrug resulted in a sustained plasma concentration profile with higher plasma exposure and lower clearance. An assessment of the urine composition revealed that the bioactivation was extensive but incomplete, with no detectable levels of the penta- or tetra-ester forms. Tissue distribution at 12 h was limited, with approximately 73% of the administered dose being associated with the gastrointestinal tract. In the efficacy study, rats were exposed to aerosols of 241Am nitrate before receiving a single oral treatment of the prodrug. The urinary excretion of 241Am was found to be 19% higher than with the control. Consistent with prior reports of DTPA, the prodrug was most effective when the treatment delays were minimized. PMID:24619514

  17. Penta-graphene: A new carbon allotrope

    PubMed Central

    Zhang, Shunhong; Zhou, Jian; Wang, Qian; Chen, Xiaoshuang; Kawazoe, Yoshiyuki; Jena, Puru

    2015-01-01

    A 2D metastable carbon allotrope, penta-graphene, composed entirely of carbon pentagons and resembling the Cairo pentagonal tiling, is proposed. State-of-the-art theoretical calculations confirm that the new carbon polymorph is not only dynamically and mechanically stable, but also can withstand temperatures as high as 1000 K. Due to its unique atomic configuration, penta-graphene has an unusual negative Poisson’s ratio and ultrahigh ideal strength that can even outperform graphene. Furthermore, unlike graphene that needs to be functionalized for opening a band gap, penta-graphene possesses an intrinsic quasi-direct band gap as large as 3.25 eV, close to that of ZnO and GaN. Equally important, penta-graphene can be exfoliated from T12-carbon. When rolled up, it can form pentagon-based nanotubes which are semiconducting, regardless of their chirality. When stacked in different patterns, stable 3D twin structures of T12-carbon are generated with band gaps even larger than that of T12-carbon. The versatility of penta-graphene and its derivatives are expected to have broad applications in nanoelectronics and nanomechanics. PMID:25646451

  18. Penta-graphene: A new carbon allotrope.

    PubMed

    Zhang, Shunhong; Zhou, Jian; Wang, Qian; Chen, Xiaoshuang; Kawazoe, Yoshiyuki; Jena, Puru

    2015-02-24

    A 2D metastable carbon allotrope, penta-graphene, composed entirely of carbon pentagons and resembling the Cairo pentagonal tiling, is proposed. State-of-the-art theoretical calculations confirm that the new carbon polymorph is not only dynamically and mechanically stable, but also can withstand temperatures as high as 1000 K. Due to its unique atomic configuration, penta-graphene has an unusual negative Poisson's ratio and ultrahigh ideal strength that can even outperform graphene. Furthermore, unlike graphene that needs to be functionalized for opening a band gap, penta-graphene possesses an intrinsic quasi-direct band gap as large as 3.25 eV, close to that of ZnO and GaN. Equally important, penta-graphene can be exfoliated from T12-carbon. When rolled up, it can form pentagon-based nanotubes which are semiconducting, regardless of their chirality. When stacked in different patterns, stable 3D twin structures of T12-carbon are generated with band gaps even larger than that of T12-carbon. The versatility of penta-graphene and its derivatives are expected to have broad applications in nanoelectronics and nanomechanics.

  19. Penta-graphene: A new carbon allotrope.

    PubMed

    Zhang, Shunhong; Zhou, Jian; Wang, Qian; Chen, Xiaoshuang; Kawazoe, Yoshiyuki; Jena, Puru

    2015-02-24

    A 2D metastable carbon allotrope, penta-graphene, composed entirely of carbon pentagons and resembling the Cairo pentagonal tiling, is proposed. State-of-the-art theoretical calculations confirm that the new carbon polymorph is not only dynamically and mechanically stable, but also can withstand temperatures as high as 1000 K. Due to its unique atomic configuration, penta-graphene has an unusual negative Poisson's ratio and ultrahigh ideal strength that can even outperform graphene. Furthermore, unlike graphene that needs to be functionalized for opening a band gap, penta-graphene possesses an intrinsic quasi-direct band gap as large as 3.25 eV, close to that of ZnO and GaN. Equally important, penta-graphene can be exfoliated from T12-carbon. When rolled up, it can form pentagon-based nanotubes which are semiconducting, regardless of their chirality. When stacked in different patterns, stable 3D twin structures of T12-carbon are generated with band gaps even larger than that of T12-carbon. The versatility of penta-graphene and its derivatives are expected to have broad applications in nanoelectronics and nanomechanics. PMID:25646451

  20. 3-Hy-droxy-2,2-bis-(1H-pyrazol-1-yl)-cyclo-penta-none.

    PubMed

    Rybakov, Victor B; Utkina, Anastasia A; Kurkin, Alexander V; Yurovskaya, Marina A

    2012-03-01

    The title compound, C(11)H(12)N(4)O(2), was unexpectedly obtained in the reaction of α,α'-disubstituted cyclo-penta-none with 1,1,3,3-tetra-meth-oxy-propane in the presence of dioxane saturated with HCl. It belongs to a previously unknown class of gem-bihetaryl ketones which may be useful for screening of new substances with biological activity. In the studied structure, the cyclo-penta-none moiety adopts an envelope conformation, with the hy-droxy-bearing C atom as the flap [deviation from basal plane = 0.643 (3) Å]. The dihedral angle between the two pyrazole rings is 80.02 (8)°. In the crystal, inversion dimers are formed via a pair of O-H⋯N hydrogen bonds. PMID:22412705

  1. Investigations into the construction of the penta-substituted ring C of Neosurugatoxin - a crystallographic study.

    PubMed

    Jones, Alan M; Storey, John M D; Harrison, William T A

    2016-01-01

    The crystal structures of three cyclo-penta-[c]furans with various substituents at the 4-, 5- and 6-positions of the ring system are reported, namely, (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl-hexa-hydro-1H-cyclo-penta-[c]furan-4,5-diol, C14H18O3, (I), (±)-(3aR,4S,5S,6aS)-4-benz-yloxy-4-methyl-5-phenyl-hexa-hydro-1H-cyclo-penta-[c]furan-5-ol, C21H24O3, (II), and (±)-(1aR,1bS,4aR,5S,5aR)-5-benz-yloxy-5-methyl-5a-phenyl-hexa-hydro-2H-oxireno[2',3':3,4]cyclopenta-[1,2-c]furan, C21H22O3, (III). The dominant inter-action in (I) and (II) is an O-H⋯O hydrogen bond across the bicyclic 5,5-ring system between the non-functionalized hy-droxy group and the tetra-hydro-furan O atom, which appears to influence the envelope conformations of the fused five-membered rings, whereas in (III), the rings have different conformations. A weak intra-molecular C-H⋯O inter-action appears to influence the degree of tilt of the phenyl ring attached to the 5-position and is different in (I) compared to (II) and (III). PMID:26870582

  2. Investigations into the construction of the penta-substituted ring C of Neosurugatoxin - a crystallographic study.

    PubMed

    Jones, Alan M; Storey, John M D; Harrison, William T A

    2016-01-01

    The crystal structures of three cyclo-penta-[c]furans with various substituents at the 4-, 5- and 6-positions of the ring system are reported, namely, (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl-hexa-hydro-1H-cyclo-penta-[c]furan-4,5-diol, C14H18O3, (I), (±)-(3aR,4S,5S,6aS)-4-benz-yloxy-4-methyl-5-phenyl-hexa-hydro-1H-cyclo-penta-[c]furan-5-ol, C21H24O3, (II), and (±)-(1aR,1bS,4aR,5S,5aR)-5-benz-yloxy-5-methyl-5a-phenyl-hexa-hydro-2H-oxireno[2',3':3,4]cyclopenta-[1,2-c]furan, C21H22O3, (III). The dominant inter-action in (I) and (II) is an O-H⋯O hydrogen bond across the bicyclic 5,5-ring system between the non-functionalized hy-droxy group and the tetra-hydro-furan O atom, which appears to influence the envelope conformations of the fused five-membered rings, whereas in (III), the rings have different conformations. A weak intra-molecular C-H⋯O inter-action appears to influence the degree of tilt of the phenyl ring attached to the 5-position and is different in (I) compared to (II) and (III).

  3. Penta-potassium μ-arsenato-bis-(hy-droxy-tetra-molybdate) dihydrate.

    PubMed

    Yu, Hai-Hui; Kong, Li; Cui, Ji-Wen; Wang, Hai-Tao

    2011-01-15

    The title arsenatomolybdate, K(5)[Mo(8)O(24)(OH)(2)(AsO(4))]·2H(2)O, which was obtained hydro-thermally, features an [AsMo(8)O(28)(OH)(2)](5-) anion, which is formed by two Mo(4)O(14)(OH) units that are linked by As in a sandwich-like fashion. The overall symmetry of the anion is m2m. The {Mo(4)O(14)(OH)} core is composed of two pairs of confacial biocta-hedral {Mo(2)O(9)} units with two μ(4)-O atoms which have been characterized as hydroxyl groups. The anions are further inter-connected by potassium cations, forming a three-dimensional network structure with the uncoordinated water mol-ecules occupying the channels. The structure is further stabilized by O-H⋯O hydrogen bonding.

  4. Community Support Gives Rise to New Penta Career Center

    ERIC Educational Resources Information Center

    McCulloch, Michelle

    2007-01-01

    For more than 40 years, Penta Career Center in Perrysburg, Ohio, has successfully served thousands of high school students and adults from Northwest Ohio. Calling a converted 1949 United States Army Depot building home, Penta serves students from 16 surrounding school districts, and offers programs in six core areas: arts and communications;…

  5. Transition metal complexes of a new 15-membered [N5] penta-azamacrocyclic ligand with their spectral and anticancer studies

    NASA Astrophysics Data System (ADS)

    El-Boraey, Hanaa A.; Serag El-Din, Azza A.

    2014-11-01

    Novel penta-azamacrocyclic 15-membered [N5] ligand [L] i.e. 1,5,8,12-tetetraaza-3,4: 9,10-dibenzo-6-ethyl-7-methyl-1,12-(2,6-pyrido)cyclopentadecan-5,7 diene-2,11-dione and its transition metal complexes with Co(II), Ni(II), Cu(II), Ru(III) and Pd(II) have been synthesized and structurally characterized by elemental analysis, spectral, thermal as well as magnetic and molar conductivity measurements. On basis of IR, MS, UV-Vis 1H NMR and EPR spectral studies an octahedral geometry has been proposed for all complexes except Co(II), Cu(II) nitrate complexes and Pd(II) chloride complex that adopt tetrahedral, square pyramidal and square planar geometries, respectively. The antitumor activity of the synthesized ligand and some complexes against human breast cancer cell lines (MCF-7) and human hepatocarcinoma cell lines (HepG2) has been studied. The complexes (IC50 = 2.04-9.7, 2.5-3.7 μg/mL) showed potent antitumor activity comparable with their ligand (IC50 = 11.7, 3.45 μg/mL) against the above mentioned cell lines, respectively. The results evidently show that the activity of the ligand becomes more pronounced and significant when coordinated to the metal ion.

  6. Investigations into the construction of the penta­substituted ring C of Neosurugatoxin – a crystallographic study

    PubMed Central

    Jones, Alan M.; Storey, John M. D.; Harrison, William T A

    2016-01-01

    The crystal structures of three cyclo­penta­[c]furans with various substituents at the 4-, 5- and 6-positions of the ring system are reported, namely, (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-4,5-diol, C14H18O3, (I), (±)-(3aR,4S,5S,6aS)-4-benz­yloxy-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-5-ol, C21H24O3, (II), and (±)-(1aR,1bS,4aR,5S,5aR)-5-benz­yloxy-5-methyl-5a-phenyl­hexa­hydro-2H-oxireno[2′,3′:3,4]cyclopenta­[1,2-c]furan, C21H22O3, (III). The dominant inter­action in (I) and (II) is an O—H⋯O hydrogen bond across the bicyclic 5,5-ring system between the non-functionalized hy­droxy group and the tetra­hydro­furan O atom, which appears to influence the envelope conformations of the fused five-membered rings, whereas in (III), the rings have different conformations. A weak intra­molecular C—H⋯O inter­action appears to influence the degree of tilt of the phenyl ring attached to the 5-position and is different in (I) compared to (II) and (III). PMID:26870582

  7. Metal-metal interactions in linear tri-, penta-, hepta-, and nona-nuclear ruthenium string complexes.

    PubMed

    Niskanen, Mika; Hirva, Pipsa; Haukka, Matti

    2012-05-01

    Density functional theory (DFT) methodology was used to examine the structural properties of linear metal string complexes: [Ru(3)(dpa)(4)X(2)] (X = Cl(-), CN(-), NCS(-), dpa = dipyridylamine(-)), [Ru(5)(tpda)(4)Cl(2)], and hypothetical, not yet synthesized complexes [Ru(7)(tpta)(4)Cl(2)] and [Ru(9)(ppta)(4)Cl(2)] (tpda = tri-α-pyridyldiamine(2-), tpta = tetra-α-pyridyltriamine(3-), ppta = penta-α-pyridyltetraamine(4-)). Our specific focus was on the two longest structures and on comparison of the string complexes and unsupported ruthenium backboned chain complexes, which have weaker ruthenium-ruthenium interactions. The electronic structures were studied with the aid of visualized frontier molecular orbitals, and Bader's quantum theory of atoms in molecules (QTAIM) was used to study the interactions between ruthenium atoms. The electron density was found to be highest and distributed most evenly between the ruthenium atoms in the hypothetical [Ru(7)(tpta)(4)Cl(2)] and [Ru(9)(ppta)(4)Cl(2)] string complexes.

  8. Thermal conductivity of penta-graphene from molecular dynamics study.

    PubMed

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-10-21

    Using classical equilibrium molecular dynamics simulations and applying the original Tersoff interatomic potential, we study the thermal transport property of the latest two dimensional carbon allotrope, penta-graphene. It is predicted that its room-temperature thermal conductivity is about 167 W/mK, which is much lower than that of graphene. With normal mode decomposition, the accumulated thermal conductivity with respect to phonon frequency and mean free path is analyzed. It is found that the acoustic phonons make a contribution of about 90% to the thermal conductivity, and phonons with mean free paths larger than 100 nm make a contribution over 50%. We demonstrate that the remarkably lower thermal conductivity of penta-graphene compared with graphene results from the lower phonon group velocities and fewer collective phonon excitations. Our study highlights the importance of structure-property relationship and provides better understanding of thermal transport property and valuable insight into thermal management of penta-graphene.

  9. Penta-hepta defect motion in hexagonal patterns

    SciTech Connect

    Tsimring, L.S.

    1995-05-22

    The structure and dynamics of penta-hepta defects (PHD`s) in hexagonal patterns are studied in the framework of coupled amplitude equations for the underlying plane waves. An analytical solution for the phase field of moving PHD is found in the far field, which generalizes the static solution due to Pismen and Nepomnyashchy. The mobility tensor of the PHD is calculated using a combined analytical and numerical approach. The results for the velocity of a PHD climbing in slightly nonoptimal hexagonal patterns are compared with numerical simulations of amplitude equations. The interaction of penta-hepta defects in optimal hexagonal patterns is considered.

  10. Poly[diaqua-(μ(4)-carboxyl-atomethyl-phospho-nato)(μ(4)-carb-oxy-methyl-phospho-nato)penta-deca-methyl-penta-tin(IV)].

    PubMed

    Boye, Mouhamadou Sembene; Diasse-Sarr, Aminata; Grosjean, Arnaud; Guionneau, Philippe

    2013-02-01

    The central Sn(IV) atom of the penta-nuclear title complex, {[Sn(CH(3))(3)](3)O(2)C(CH(2))PO(3)[Sn(CH(3))(3)(H(2)O)](2)HO(2)C(CH(2))PO(3)}, is located on a twofold rotation axis; due to symmetry, the H atom of the carboxyl group of the anion is disordered with a site occupancy of 0.5. The central Sn(IV) atom is bonded to three methyl groups (one of which is disordered about the twofold rotation axis) and is symmetrically trans coordinated by two phospho-nate groups with Sn-O = 2.2665 (12) Å while the other SnMe(3) residues are asymmetrically trans coordinated with Sn-O = 2.1587 (12) and 2.3756 (13) Å for one residue and Sn-O = 2.1522 (12) and 2.4335 (12) Å for the other; the Sn-O distances involving two O atoms trans to carboxyl-ate are longer than those trans to phospho-nate groups. The Sn-C distances lie in a very narrow range [2.112 (2)-2.133 (3) Å]. The oxyanion behaves as a tetra-coordinating ligand. The bridging mode of the latter leads to the formation of layers parallel to (001) that are inter-connected by O-H⋯O and C-H⋯O hydrogen bonds. PMID:23424406

  11. New Penta(tetrathiafulvalenyl)[60]fullerenes for Supramolecular Materials.

    PubMed

    Busseau, Antoine; Villegas, Carmen; Dabos-Seignon, Sylvie; Cabanetos, Clément; Hudhomme, Piétrick; Legoupy, Stéphanie

    2016-06-13

    New penta(organo)fullerenes donor-acceptor systems bearing five tetrathiafulvalene recognition units have been synthesized to promote self-assemblies similar in appearance to shuttlecocks nested into each other thanks to the conical host cavity created around the fullerene together with the π-π and electronic interactions. PMID:27061313

  12. New Penta(tetrathiafulvalenyl)[60]fullerenes for Supramolecular Materials.

    PubMed

    Busseau, Antoine; Villegas, Carmen; Dabos-Seignon, Sylvie; Cabanetos, Clément; Hudhomme, Piétrick; Legoupy, Stéphanie

    2016-06-13

    New penta(organo)fullerenes donor-acceptor systems bearing five tetrathiafulvalene recognition units have been synthesized to promote self-assemblies similar in appearance to shuttlecocks nested into each other thanks to the conical host cavity created around the fullerene together with the π-π and electronic interactions.

  13. Pyrolysis of the tetra pak

    SciTech Connect

    Korkmaz, Ahmet; Yanik, Jale Brebu, Mihai; Vasile, Cornelia

    2009-11-15

    This study deals with pyrolysis of tetra pak which is widely used as an aseptic beverage packaging material. Pyrolysis experiments were carried out under inert atmosphere in a batch reactor at different temperatures and by different pyrolysis modes (one- and two-step). The yields of char, liquid and gas were quantified. Pyrolysis liquids produced were collected as three separate phases; aqueous phase, tar and polyethylene wax. Characterization of wax and the determination of the total amount of phenols in aqueous phase were performed. Chemical compositions of gas and char products relevant to fuel applications were determined. Pure aluminum can be also recovered by pyrolysis.

  14. Predicting experimentally stable allotropes: Instability of penta-graphene

    PubMed Central

    Ewels, Christopher P.; Rocquefelte, Xavier; Kroto, Harold W.; Rayson, Mark J.; Briddon, Patrick R.; Heggie, Malcolm I.

    2015-01-01

    In recent years, a plethora of theoretical carbon allotropes have been proposed, none of which has been experimentally isolated. We discuss here criteria that should be met for a new phase to be potentially experimentally viable. We take as examples Haeckelites, 2D networks of sp2-carbon–containing pentagons and heptagons, and “penta-graphene,” consisting of a layer of pentagons constructed from a mixture of sp2- and sp3-coordinated carbon atoms. In 2D projection appearing as the “Cairo pattern,” penta-graphene is elegant and aesthetically pleasing. However, we dispute the author’s claims of its potential stability and experimental relevance. PMID:26644554

  15. Penta­lanthanum zinc diplumbide, La5Zn1−xPb2+x (x ≃ 0.6)

    PubMed Central

    Oshchapovsky, Igor; Pavlyuk, Volodymyr; Dmytriv, Grygoriy; Harbrecht, Bernd

    2014-01-01

    The title non-stoichiometric penta­lanthanum zinc diplumbide, La5Zn1−xPb2+x (x ≃ 0.6), was prepared from the elements in an evacuated silica ampoule. It adopts the Nb5Sn2Si-type structure (space group I4/mcm, Pearson symbol tI32), a ternary ordered superstructure of the W5Si3 type. Among the four independent crystallographic positions, three are fully occupied by La (Wyckoff 16k), La (4b), and Pb (8h) and one is occupied by a statistical mixture [occupancy ratio 0.394 (12):0.606 (12)] of Zn and Pb (4a). The structure is constructed by face-sharing 10-vertex polyhedra around the unmixed Pb sites. These fragments enclose channels of trans-face-sharing tetra­gonal anti­prisms occupied by the disordered Zn and Pb sites. PMID:24526938

  16. Synthesis and structure-activity relationship study of antidiabetic penta-O-galloyl-D-glucopyranose and its analogues.

    PubMed

    Ren, Yulin; Himmeldirk, Klaus; Chen, Xiaozhuo

    2006-05-01

    The rapid increase of obesity-associated diabetes has created urgent demands for more effective antidiabetic therapies and pharmaceuticals that are able to address the problems of hyperglycemia and weight gain simultaneously. Our previous studies indicated that the alpha- and beta-anomers of penta-O-galloyl-D-glucopyranose (PGG), 2 and 3, act as insulin mimetics that bind to and activate the insulin receptor, stimulate glucose transport in adipocytes, and reduce blood glucose and insulin levels in diabetic and obese animals. In addition, they inhibit differentiation of preadipocytes into adipocytes. These activities suggest that 2 and 3 may reduce blood glucose without increasing adiposity. To investigate the structure-activity relationship of 2 and 3, four series of novel compounds were prepared and their glucose transport stimulatory activities were measured using a radioactive glucose uptake bioassay. The assay results indicate that both the glucose and the galloyl groups are critical to the activity of 2 and 3. It appears that the glucose core provides an optimal scaffold to present the galloyl groups with the correct spatial orientation to induce activity. Moreover, the galloyl groups linked to the 1, 2, 3, and 4 positions of glucose are essential, while the galloyl group connected to the 6 position of 2 is unnecessary for the induction of activity. The discovery that two related novel compounds, 6-deoxytetra-O-galloyl-alpha-D-glucopyranose (43) and tetra-O-galloyl-alpha-D-xylopyranose (59), also possess glucose transport stimulatory activity suggests that 2 may be further modified around position 6 to modulate and enhance its efficacy. To test this hypothesis, we developed a new synthetic method that allows for the stereoselective preparation of derivatives of 2 that are modified on C-6. We found that 6-chloro-6-deoxy-1,2,3,4-tetra-O-galloyl-alpha-D-glucopyranose (80) exhibits a significantly higher glucose transport stimulatory activity than 2. Its activity

  17. Disparate Strain Dependent Thermal Conductivity of Two-dimensional Penta-Structures.

    PubMed

    Liu, Huake; Qin, Guangzhao; Lin, Yuan; Hu, Ming

    2016-06-01

    Two-dimensional (2D) carbon allotrope called penta-graphene was recently proposed from first-principles calculations and various similar penta-structures emerged. Despite significant effort having been dedicated to electronic structures and mechanical properties, little research has been focused on thermal transport in penta-structures. Motivated by this, we performed a comparative study of thermal transport properties of three representative pentagonal structures, namely penta-graphene, penta-SiC2, and penta-SiN2, by solving the phonon Boltzmann transport equation with interatomic force constants extracted from first-principles calculations. Unexpectedly, the thermal conductivity of the three penta-structures exhibits diverse strain dependence, despite their very similar geometry structures. While the thermal conductivity of penta-graphene exhibits standard monotonic reduction by stretching, penta-SiC2 possesses an unusual nonmonotonic up-and-down behavior. More interestingly, the thermal conductivity of penta-SiN2 has 1 order of magnitude enhancement due to the strain induced buckled to planar structure transition. The mechanism governing the diverse strain dependence is identified as the competition between the change of phonon group velocity and phonon lifetime of acoustic phonon modes with combined effect from the unique structure transition for penta-SiN2. The disparate thermal transport behavior is further correlated to the fundamentally different bonding nature in the atomic structures with solid evidence from the distribution of deformation charge density and more in-depth molecular orbital analysis. The reported giant and robust tunability of thermal conductivity may inspire intensive research on other derivatives of penta-structures as potential materials for emerging nanoelectronic devices. The fundamental physics understood from this study also solidifies the strategy to engineer thermal transport properties of broad 2D materials by simple mechanical

  18. Disparate Strain Dependent Thermal Conductivity of Two-dimensional Penta-Structures.

    PubMed

    Liu, Huake; Qin, Guangzhao; Lin, Yuan; Hu, Ming

    2016-06-01

    Two-dimensional (2D) carbon allotrope called penta-graphene was recently proposed from first-principles calculations and various similar penta-structures emerged. Despite significant effort having been dedicated to electronic structures and mechanical properties, little research has been focused on thermal transport in penta-structures. Motivated by this, we performed a comparative study of thermal transport properties of three representative pentagonal structures, namely penta-graphene, penta-SiC2, and penta-SiN2, by solving the phonon Boltzmann transport equation with interatomic force constants extracted from first-principles calculations. Unexpectedly, the thermal conductivity of the three penta-structures exhibits diverse strain dependence, despite their very similar geometry structures. While the thermal conductivity of penta-graphene exhibits standard monotonic reduction by stretching, penta-SiC2 possesses an unusual nonmonotonic up-and-down behavior. More interestingly, the thermal conductivity of penta-SiN2 has 1 order of magnitude enhancement due to the strain induced buckled to planar structure transition. The mechanism governing the diverse strain dependence is identified as the competition between the change of phonon group velocity and phonon lifetime of acoustic phonon modes with combined effect from the unique structure transition for penta-SiN2. The disparate thermal transport behavior is further correlated to the fundamentally different bonding nature in the atomic structures with solid evidence from the distribution of deformation charge density and more in-depth molecular orbital analysis. The reported giant and robust tunability of thermal conductivity may inspire intensive research on other derivatives of penta-structures as potential materials for emerging nanoelectronic devices. The fundamental physics understood from this study also solidifies the strategy to engineer thermal transport properties of broad 2D materials by simple mechanical

  19. Hexaaqua-cobalt(II) 5,5'-(propane-1,3-diyldithio)bis-(1H-tetra-zole-1-acetate).

    PubMed

    Liang, Wan-Ling; Yu, Qing; Zhang, Xiu-Qing; Qin, Jiang-Ke; Liang, Hong

    2009-07-29

    The asymmetric unit of the title complex, [Co(H(2)O)(6)](C(9)H(10)N(8)O(4)S(2)), contains one-half of a [Co(H(2)O)(6)](2+) cation and one-half of a 5,5'-(propane-1,3-diyldithio)bis-(1H-tetra-zole-1-acetate) (battp(2-)) anion. The Co(II) center is coordinated by six H(2)O mol-ecules in a distorted octa-hedral coordination environment. In the crystal structure, intra- and inter-molecular O-H⋯O and O-H⋯N hydrogen bonds link the cations and anions into a three-dimensional network. π-π contacts between the tetra-zole rings [centroid-centroid distance = 3.346 (1) Å] may further stabilize the structure.

  20. Zirconium(IV) dilanthanum(III) penta­sulfide

    PubMed Central

    Raw, Adam D.; Ibers, James A.

    2011-01-01

    Zirconium(IV) dilanthanum(III) penta­sulfide, ZrLa2S5, crystallizes with four formula units in the space group Pnma in the U3S5 structure type. The asymmetric unit comprises one Zr, one La and four S atoms. The Zr and three S atoms are situated on mirror planes. The structure consists of LaS8 face-sharing bicapped distorted trigonal prisms and ZrS7 edge-sharing monocapped octa­hedra. PMID:22199468

  1. Mono- and polynuclear Co(II) silanethiolates with aliphatic diamines

    NASA Astrophysics Data System (ADS)

    Pladzyk, Agnieszka; Baranowska, Katarzyna

    2014-01-01

    Four Co(II) complexes, [Co{SSi(OtBu)3}2(dmpda)] 1, [Co{SSi(OtBu)3}2(bda)2]n2 [Co{SSi(OtBu)3}2(pda)2]n3 and [Co{SSi(OtBu)3}2(hda)2]n4 [dmpda = 3-(dimethylamino)-1-propylamine; bda = 1.4-butanediamine; pda = 1.5-pentanediamine; had = 1.6-hexanediamine] have been synthesized and characterized using X-ray diffraction. Complex 1 is mononuclear and contains Co(II) coordinated by dmpda molecule in chelating mode, whereas compounds 3 and 4 are one-dimensional polymers with pda and hda diamines as bridges between the metallic centers respectively. In all complexes tri-tert-butoxysilanethiolate residue acts as terminal S-donor ligand. Full characterization of obtained compounds 1-4 was additionally carried out with the use of IR and UV-vis spectroscopy, elemental and thermal analysis.

  2. Glycine zinc sulfate penta­hydrate: redetermination at 10 K from time-of-flight neutron Laue diffraction

    PubMed Central

    Fortes, A. Dominic; Howard, Christopher M.; Wood, Ian G.; Gutmann, Matthias J.

    2016-01-01

    Single crystals of glycine zinc sulfate penta­hydrate [systematic name: hexa­aqua­zinc tetra­aquadiglycinezinc bis­(sulfate)], [Zn(H2O)6][Zn(C2H5NO2)2(H2O)4](SO4)2, have been grown by isothermal evaporation from aqueous solution at room temperature and characterized by single-crystal neutron diffraction. The unit cell contains two unique ZnO6 octa­hedra on sites of symmetry -1 and two SO4 tetra­hedra with site symmetry 1; the octa­hedra comprise one [tetra­aqua-diglycine zinc]2+ ion (centred on one Zn atom) and one [hexa­aqua­zinc]2+ ion (centred on the other Zn atom); the glycine zwitterion, NH3 +CH2COO−, adopts a monodentate coordination to the first Zn atom. All other atoms sit on general positions of site symmetry 1. Glycine forms centrosymmetric closed cyclic dimers due to N—H⋯O hydrogen bonds between the amine and carboxyl­ate groups of adjacent zwitterions and exhibits torsion angles varying from ideal planarity by no more than 1.2°, the smallest values for any known glycine zwitterion not otherwise constrained by a mirror plane. This work confirms the H-atom locations estimated in three earlier single-crystal X-ray diffraction studies with the addition of independently refined fractional coordinates and Uij parameters, which provide accurate inter­nuclear X—H (X = N, O) bond lengths and consequently a more accurate and precise depiction of the hydrogen-bond framework. PMID:27746937

  3. 21 CFR 582.6789 - Tetra sodium pyrophosphate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Tetra sodium pyrophosphate. 582.6789 Section 582.6789 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....6789 Tetra sodium pyrophosphate. (a) Product. Tetra sodium pyrophosphate. (b) Conditions of use....

  4. 21 CFR 182.6789 - Tetra sodium pyrophosphate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Tetra sodium pyrophosphate. 182.6789 Section 182...) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 1 § 182.6789 Tetra sodium pyrophosphate. (a) Product. Tetra sodium pyrophosphate. (b) Conditions of use. This substance is generally recognized as safe...

  5. 40 CFR 721.10430 - Tetra alkyl ammonium salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Tetra alkyl ammonium salt (generic... Specific Chemical Substances § 721.10430 Tetra alkyl ammonium salt (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as tetra...

  6. 40 CFR 721.10430 - Tetra alkyl ammonium salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Tetra alkyl ammonium salt (generic... Specific Chemical Substances § 721.10430 Tetra alkyl ammonium salt (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as tetra...

  7. 21 CFR 582.6789 - Tetra sodium pyrophosphate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....6789 Tetra sodium pyrophosphate. (a) Product. Tetra sodium pyrophosphate. (b) Conditions of use. This... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetra sodium pyrophosphate. 582.6789 Section 582.6789 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  8. Penta-BxNy sheet: a density functional theory study of two-dimensional material.

    PubMed

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Chen, Gang

    2016-01-01

    By using density functional theory with generalized gradient approximation, we have carried out detailed investigations of two-dimensional BxNy nanomaterials in the Cairo pentagonal tiling geometry fully composed of pentagons (penta-BxNy). Only penta-BN and BN2 planar structures are dynamically stable without imaginary modes in their phonon spectra. Their stabilities have been further evaluated by formation energy analysis, first-principles molecular dynamics simulation, and mechanical stability analysis. Penta-BN2 is superior to penta-BN in structural stability. Its stability analysis against oxidization and functional group adsorption as well as its synthesizing reaction path analysis show possibilities in fabricating penta-BN2 on experiment. Furthermore, the penta-BN2 could be transferred from metallic to semiconducting by ionizing or covalently binding an electron per dinitrogen. Also, it has been found to have superior mechanical properties, such as the negative Poisson's ratio and the comparable stiffness as that of hexagonal h-BN sheet. These studies on the stabilities, electronic properties, and mechanical properties suggest penta-BN2 as an attractive material to call for further studies on both theory and experiment. PMID:27539445

  9. Penta-BxNy sheet: a density functional theory study of two-dimensional material

    NASA Astrophysics Data System (ADS)

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Chen, Gang

    2016-08-01

    By using density functional theory with generalized gradient approximation, we have carried out detailed investigations of two-dimensional BxNy nanomaterials in the Cairo pentagonal tiling geometry fully composed of pentagons (penta-BxNy). Only penta-BN and BN2 planar structures are dynamically stable without imaginary modes in their phonon spectra. Their stabilities have been further evaluated by formation energy analysis, first-principles molecular dynamics simulation, and mechanical stability analysis. Penta-BN2 is superior to penta-BN in structural stability. Its stability analysis against oxidization and functional group adsorption as well as its synthesizing reaction path analysis show possibilities in fabricating penta-BN2 on experiment. Furthermore, the penta-BN2 could be transferred from metallic to semiconducting by ionizing or covalently binding an electron per dinitrogen. Also, it has been found to have superior mechanical properties, such as the negative Poisson’s ratio and the comparable stiffness as that of hexagonal h-BN sheet. These studies on the stabilities, electronic properties, and mechanical properties suggest penta-BN2 as an attractive material to call for further studies on both theory and experiment.

  10. Penta-BxNy sheet: a density functional theory study of two-dimensional material

    PubMed Central

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Chen, Gang

    2016-01-01

    By using density functional theory with generalized gradient approximation, we have carried out detailed investigations of two-dimensional BxNy nanomaterials in the Cairo pentagonal tiling geometry fully composed of pentagons (penta-BxNy). Only penta-BN and BN2 planar structures are dynamically stable without imaginary modes in their phonon spectra. Their stabilities have been further evaluated by formation energy analysis, first-principles molecular dynamics simulation, and mechanical stability analysis. Penta-BN2 is superior to penta-BN in structural stability. Its stability analysis against oxidization and functional group adsorption as well as its synthesizing reaction path analysis show possibilities in fabricating penta-BN2 on experiment. Furthermore, the penta-BN2 could be transferred from metallic to semiconducting by ionizing or covalently binding an electron per dinitrogen. Also, it has been found to have superior mechanical properties, such as the negative Poisson’s ratio and the comparable stiffness as that of hexagonal h-BN sheet. These studies on the stabilities, electronic properties, and mechanical properties suggest penta-BN2 as an attractive material to call for further studies on both theory and experiment. PMID:27539445

  11. Penta-Quark States with Strangeness, Hidden Charm and Beauty

    NASA Astrophysics Data System (ADS)

    Wu, Jia-Jun; Zou, Bing-Song

    The classical quenched quark models with three constituent quarks provide a good description for the baryon spatial ground states, but fail to reproduce the spectrum of baryon excited states. More and more evidences suggest that unquenched effects with multi-quark dynamics are necessary ingredients to solve the problem. Several new hyperon resonances reported recently could fit in the picture of penta-quark states. Based on this picture, some new hyperon excited states were predicted to exist; meanwhile with extension from strangeness to charm and beauty, super-heavy narrow N* and Λ* resonances with hidden charm or beauty were predicted to be around 4.3 and 11 GeV, respectively. Recently, two of such N* with hidden charm might have been observed by the LHCb experiment. More of those states are expected to be observed in near future. This opens a new window in order to study hadronic dynamics for the multi-quark states.

  12. Tight-binding approach to penta-graphene

    PubMed Central

    Stauber, T.; Beltrán, J. I.; Schliemann, J.

    2016-01-01

    We introduce an effective tight-binding model to discuss penta-graphene and present an analytical solution. This model only involves the π-orbitals of the sp2-hybridized carbon atoms and reproduces the two highest valence bands. By introducing energy-dependent hopping elements, originating from the elimination of the sp3-hybridized carbon atoms, also the two lowest conduction bands can be well approximated - but only after the inclusion of a Hubbard onsite interaction as well as of assisted hopping terms. The eigenfunctions can be approximated analytically for the effective model without energy-dependent hopping elements and the optical absorption is discussed. We find large isotropic absorption ranging from 7.5% up to 24% for transitions at the Γ-point. PMID:26940279

  13. Doped penta-graphene and hydrogenation of its related structures: a structural and electronic DFT-D study.

    PubMed

    Quijano-Briones, J J; Fernández-Escamilla, H N; Tlahuice-Flores, A

    2016-06-21

    The structure of penta-graphene (penta-C), an irregular pentagonal two-dimensional (2D) structure, has been predicted recently. In this communication we carried out a dispersion-corrected density functional theory (DFT-D) study of the penta-C doped with Si, Ge and Sn atoms and its related hydrogenated penta-C structures (H-penta-C-X). We predict various new structures as thermally stable based on Born-Oppenheimer molecular dynamics (BOMD) calculations. Moreover, their dynamical stability is attested by phonon dispersions spectra. In general, we found that the bandgap value of doped structures reduces, while H-penta-C-X show large bandgap values. This feature can be exploited for potential uses of hydrogenated doped-penta-C structures as dielectric layers in electronic devices.

  14. Doped penta-graphene and hydrogenation of its related structures: a structural and electronic DFT-D study.

    PubMed

    Quijano-Briones, J J; Fernández-Escamilla, H N; Tlahuice-Flores, A

    2016-06-21

    The structure of penta-graphene (penta-C), an irregular pentagonal two-dimensional (2D) structure, has been predicted recently. In this communication we carried out a dispersion-corrected density functional theory (DFT-D) study of the penta-C doped with Si, Ge and Sn atoms and its related hydrogenated penta-C structures (H-penta-C-X). We predict various new structures as thermally stable based on Born-Oppenheimer molecular dynamics (BOMD) calculations. Moreover, their dynamical stability is attested by phonon dispersions spectra. In general, we found that the bandgap value of doped structures reduces, while H-penta-C-X show large bandgap values. This feature can be exploited for potential uses of hydrogenated doped-penta-C structures as dielectric layers in electronic devices. PMID:27220553

  15. Dynamics of a penta-hepta defect in a hexagonal pattern

    PubMed

    Tam; Ohata; Wu

    2000-01-01

    The structure and dynamics of a penta-hepta defect in a hexagonal pattern are studied experimentally. The hexagonal pattern is formed by placing a layer of soap bubbles (diameter approximately 1 mm) on a flat glass plate. We find that an isolated penta-hepta defect in a bubble raft with free boundary always moves along the direction perpendicular to the wave vector of the nonsingular mode and towards the nearest boundary. The structure of the penta-hepta defect is found to be similar to that found in nonequilibrium pattern forming systems. PMID:11046360

  16. Removal efficiencies for 136 tetra- through octa-chlorinated dibenzo-p-dioxins and dibenzofuran congeners with activated carbons.

    PubMed

    Zhou, Xu-Jian; Li, Xiao-Dong; Ni, Ming-Jiang; Cen, Ke-Fa

    2015-11-01

    In this study, the removal efficiency of 136 tetra- to octa-chlorinated dibenzo-p-dioxin (CDD)/furan (F) congeners from a nitrogen + oxygen carrier gas was studied using a laboratory-scale, fixed bed adsorption system. Two kinds of activated carbon with dissimilar pore structures were used as adsorbents. The total concentration of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in the source gas was 541 ng/Nm(3) and that of the 17 toxic 2,3,7,8-substituted PCDD/Fs 96.35 ng/Nm(3), accounting for 17.8% of the total original weight amount. Their toxic equivalent quantity (TEQ) was 8.31 ng I-TEQ/Nm(3). For both activated carbons, the removal efficiencies of the ten PCDD/F homologue groups rise with chlorine substitution number. The removal efficiencies vary approximately as a power function of vapor pressure (correlation coefficients r(2) = 0.93 and 0.81, respectively). Competitive adsorption and desorption occur as adsorption time went on, causing elution of the lower chlorinated homologues, i.e. tetra-CDD/F and Penta-CDD/F congeners. In addition, there are significantly different concentration distributions for isomers in the same homologue groups. However, their removal efficiencies have weak correlation with their initial concentrations. The correlation coefficients are from -0.47 to 0.32 and from -0.57 to 0.46 respectively for the two kinds of activated carbons.

  17. A first-principles study of stable few-layer penta-silicene.

    PubMed

    Aierken, Yierpan; Leenaerts, Ortwin; Peeters, François M

    2016-07-21

    Recently penta-graphene was proposed as a stable two-dimensional carbon allotrope consisting of a single layer of interconnected carbon pentagons [Zhang et al., PNAS, 2015, 112, 2372]. Its silicon counterpart, penta-silicene, however, is not stable. In this work, we show that multilayers of penta-silicene form stable materials with semiconducting or metallic properties, depending on the stacking mode. We demonstrate their dynamic stability through their phonon spectrum and using molecular dynamics. A particular type of bilayer penta-silicene is found to have lower energy than all of the known hexagonal silicene bilayers and forms therefore the most stable bilayer silicon material predicted so far. The electronic and mechanical properties of these new silicon allotropes are studied in detail and their behavior under strain is investigated. We demonstrate that strain can be used to tune its band gap.

  18. Sub-Camera Calibration of a Penta-Camera

    NASA Astrophysics Data System (ADS)

    Jacobsen, K.; Gerke, M.

    2016-03-01

    Penta cameras consisting of a nadir and four inclined cameras are becoming more and more popular, having the advantage of imaging also facades in built up areas from four directions. Such system cameras require a boresight calibration of the geometric relation of the cameras to each other, but also a calibration of the sub-cameras. Based on data sets of the ISPRS/EuroSDR benchmark for multi platform photogrammetry the inner orientation of the used IGI Penta DigiCAM has been analyzed. The required image coordinates of the blocks Dortmund and Zeche Zollern have been determined by Pix4Dmapper and have been independently adjusted and analyzed by program system BLUH. With 4.1 million image points in 314 images respectively 3.9 million image points in 248 images a dense matching was provided by Pix4Dmapper. With up to 19 respectively 29 images per object point the images are well connected, nevertheless the high number of images per object point are concentrated to the block centres while the inclined images outside the block centre are satisfying but not very strongly connected. This leads to very high values for the Student test (T-test) of the finally used additional parameters or in other words, additional parameters are highly significant. The estimated radial symmetric distortion of the nadir sub-camera corresponds to the laboratory calibration of IGI, but there are still radial symmetric distortions also for the inclined cameras with a size exceeding 5μm even if mentioned as negligible based on the laboratory calibration. Radial and tangential effects of the image corners are limited but still available. Remarkable angular affine systematic image errors can be seen especially in the block Zeche Zollern. Such deformations are unusual for digital matrix cameras, but it can be caused by the correlation between inner and exterior orientation if only parallel flight lines are used. With exception of the angular affinity the systematic image errors for corresponding

  19. [Genetic study of the Penta E locus and identification of rare alleles].

    PubMed

    Lai, Li; Shen, Xiaoli; Han, Lili; Chen, Dian; Hu, Jie

    2015-10-01

    OBJECTIVE To study the genetic polymorphisms of Penta E locus in Fujian Han population. METHODS Polymorphisms of the Penta E locus in 851 unrelated individuals were analyzed using polymerase chain reaction-short tandem repeat (PCR-STR). The mutation rate of rare alleles was analyzed in 494 paternity identification cases (in a total of 674 meiosis). RESULTS Twenty-six alleles were identified for the Penta E locus, with their frequencies ranging from 0.0006 to 0.1528. There were 7 rare alleles, among which Penta E-28.4 ([AAAGA]29) was identified for the first time. Genetic parameters of the Penta E locus in Fujian Han population were obtained, including PIC= 0.91, PE= 0.817, PD= 0.986, and mutation rate= 0.0015. CONCLUSION The Penta E locus is highly polymorphic and has a low mutation rate in Fujian Han population. It also has a good prospect in genetics applications. DNA sequencing is a good method for identifying rare alleles. PMID:26418985

  20. Sequence change and phylogenetic signal in muscoid COII DNA sequences.

    PubMed

    Szalanski, Allen L; Owens, Carrie B

    2003-08-01

    The complete DNA sequence of the mtDNA cytochrome oxidase II gene from house fly, Musca domestica, face fly, Musca autumnalis, stable fly, Stomoxys calcitrans, horn fly, Haematobia irritans, and black garbage fly, Hydrotaea aenescens, are reported. The nucleotide sequence codes for a 229 amino acid peptide. The COII sequence is A + T rich (74.1%), with up to 12.3% nucleotide and 8.4% amino acid divergence among the five taxa. Of the 688 nucleotides encoding for the gene, 135 nucleotide sites (19.6%) are variable, and 55 (8.0%) are phylogenetically informative. A phylogenetic analysis using three calliphorids as the outgroup taxa, indicates that the two haematophagus species, horn fly and stable fly, form a sister group.

  1. Triggering of suicidal erythrocyte death by penta-O-galloyl-β-D-glucose.

    PubMed

    Alzoubi, Kousi; Honisch, Sabina; Abed, Majed; Lang, Florian

    2013-12-24

    The polyphenolic 1,2,3,4,6-penta-O-galloyl-beta-D-glucose from several medicinal herbs triggers apoptosis and has, thus, been proposed for treatment of malignancy. The substance is at least partially effective through caspase activation. In analogy to apoptosis of nucleated cells, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by phosphatidylserine translocation to the erythrocyte surface. Eryptosis is triggered by increase of cytosolic Ca2+-activity ([Ca2+]i). The sensitivity to [Ca2+]i is enhanced by ceramide. The present study explored whether penta-O-galloyl-β-D-glucose stimulates eryptosis. Cell volume was estimated from forward scatter, phosphatidylserine exposure from annexin V binding, hemolysis from hemoglobin-release, [Ca2+]i from Fluo3-fluorescence and ceramide abundance from fluorescent antibodies. A 48-h exposure of human erythrocytes to penta-O-galloyl-β-D-glucose significantly decreased forward scatter (50 µM) and significantly increased annexin V binding (10 µM). Up to 50 µM penta-O-galloyl-β-D-glucose did not significantly modify [Ca2+]i. However, the effect of penta-O-galloyl-β-D-glucose (25 µM) induced annexin V binding was slightly, but significantly, blunted by removal of extracellular Ca2+, pointing to sensitization of erythrocytes to the scrambling effect of Ca2+. Penta-O-galloyl-β-D-glucose (25 µM) further increased ceramide formation. In conclusion, penta-O-galloyl-β-D-glucose stimulates suicidal erythrocyte death or eryptosis, an effect partially due to stimulation of ceramide formation with subsequent sensitization of erythrocytes to Ca2+.

  2. Crystal structure of tetra-guanidinium [hexa-hydrogen hexa-arsenato(V)tetra-vanadate(V)] tetra-hydrate.

    PubMed

    Harrison, William T A

    2014-09-01

    The complete polyoxidometallate anion in the title compound, (CH6N3)4[H6V4As6O30]·4H2O, is generated by crystallographic inversion symmetry. The polyhedral building units are distorted VO6 octa-hedra and AsO3OH tetra-hedra. The VO6 units feature a short formal V=O double bond and are linked by a common edge. Two such V2O6 double octahedral units are linked by four isolated AsO3OH tetra-hedra to complete the anion, which features two inter-nal O-H⋯O hydrogen bonds. In the crystal, O-H⋯O hydrogen bonds between the polyoxidometallate anions generate (01-1) sheets. The sheets are connected by cation-to-cluster N-H⋯O hydrogen bonds, and cation-to-water N-H⋯O links also occur. The O atom of one of the water mol-ecules is disordered over two sites in a 0.703 (17):0.297 (17) ratio.

  3. Dietary protein source and level alters growth in neon tetras.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutritional studies for aquarium fish like the neon tetra are sparse in comparison with those for food fish. To determine the optimum dietary protein level and source for growth of neon tetras, diets were formulated to contain 25, 35, 45 and 55% dietary protein from either marine animal protein or ...

  4. Recoverable plasticity in penta-twinned metallic nanowires governed by dislocation nucleation and retraction

    PubMed Central

    Qin, Qingquan; Yin, Sheng; Cheng, Guangming; Li, Xiaoyan; Chang, Tzu-Hsuan; Richter, Gunther; Zhu, Yong; Gao, Huajian

    2015-01-01

    There has been relatively little study on time-dependent mechanical properties of nanowires, in spite of their importance for the design, fabrication and operation of nanoscale devices. Here we report a dislocation-mediated, time-dependent and fully reversible plastic behaviour in penta-twinned silver nanowires. In situ tensile experiments inside scanning and transmission electron microscopes show that penta-twinned silver nanowires undergo stress relaxation on loading and complete plastic strain recovery on unloading, while the same experiments on single-crystalline silver nanowires do not exhibit such a behaviour. Molecular dynamics simulations reveal that the observed behaviour in penta-twinned nanowires originates from the surface nucleation, propagation and retraction of partial dislocations. More specifically, vacancies reduce dislocation nucleation barrier, facilitating stress relaxation, while the twin boundaries and their intrinsic stress field promote retraction of partial dislocations, resulting in full strain recovery. PMID:25585295

  5. Removal efficiencies for 136 tetra- through octa-chlorinated dibenzo-p-dioxins and dibenzofuran congeners with activated carbons.

    PubMed

    Zhou, Xu-Jian; Li, Xiao-Dong; Ni, Ming-Jiang; Cen, Ke-Fa

    2015-11-01

    In this study, the removal efficiency of 136 tetra- to octa-chlorinated dibenzo-p-dioxin (CDD)/furan (F) congeners from a nitrogen + oxygen carrier gas was studied using a laboratory-scale, fixed bed adsorption system. Two kinds of activated carbon with dissimilar pore structures were used as adsorbents. The total concentration of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in the source gas was 541 ng/Nm(3) and that of the 17 toxic 2,3,7,8-substituted PCDD/Fs 96.35 ng/Nm(3), accounting for 17.8% of the total original weight amount. Their toxic equivalent quantity (TEQ) was 8.31 ng I-TEQ/Nm(3). For both activated carbons, the removal efficiencies of the ten PCDD/F homologue groups rise with chlorine substitution number. The removal efficiencies vary approximately as a power function of vapor pressure (correlation coefficients r(2) = 0.93 and 0.81, respectively). Competitive adsorption and desorption occur as adsorption time went on, causing elution of the lower chlorinated homologues, i.e. tetra-CDD/F and Penta-CDD/F congeners. In addition, there are significantly different concentration distributions for isomers in the same homologue groups. However, their removal efficiencies have weak correlation with their initial concentrations. The correlation coefficients are from -0.47 to 0.32 and from -0.57 to 0.46 respectively for the two kinds of activated carbons. PMID:26154037

  6. Tetra- versus Pentavalent Inhibitors of Cholera Toxin**

    PubMed Central

    Fu, Ou; Pukin, Aliaksei V; van Ufford, H C Quarles; Branson, Thomas R; Thies-Weesie, Dominique M E; Turnbull, W Bruce; Visser, Gerben M; Pieters, Roland J

    2015-01-01

    The five B-subunits (CTB5) of the Vibrio cholerae (cholera) toxin can bind to the intestinal cell surface so the entire AB5 toxin can enter the cell. Simultaneous binding can occur on more than one of the monosialotetrahexosylganglioside (GM1) units present on the cell surface. Such simultaneous binding arising from the toxins multivalency is believed to enhance its affinity. Thus, blocking the initial attachment of the toxin to the cell surface using inhibitors with GM1 subunits has the potential to stop the disease. Previously we showed that tetravalent GM1 molecules were sub-nanomolar inhibitors of CTB5. In this study, we synthesized a pentavalent version and compared the binding and potency of penta- and tetravalent cholera toxin inhibitors, based on the same scaffold, for the first time. The pentavalent geometry did not yield major benefits over the tetravalent species, but it was still a strong inhibitor, and no major steric clashes occurred when binding the toxin. Thus, systems which can adopt more geometries, such as those described here, can be equally potent, and this may possibly be due to their ability to form higher-order structures or simply due to more statistical options for binding. PMID:26478842

  7. Synthesis, spectroscopic and catalytic studies of Cu(II), Co(II) and Ni(II) complexes immobilized on Schiff base modified chitosan

    NASA Astrophysics Data System (ADS)

    Antony, R.; Theodore David Manickam, S.; Saravanan, K.; Karuppasamy, K.; Balakumar, S.

    2013-10-01

    A new class of bidentate (N, O) Schiff base ligand (L) has been derived from the functional biopolymer (chitosan) and 1,2-diphenylethanedione in 1:1 M ratio. This ligand has been used to synthesise the new first row transition metal complexes of Cu(II), Co(II) and Ni(II). The structural properties of the ligand and the synthesized tetra-coordinated complexes have been investigated by elemental analysis, magnetic study, molar conductance measurement and spectroscopic methods viz. FT-IR, UV-Vis., 1H NMR, 13C NMR and XRD. The spectral evidences strongly suggested the square planar geometry to the complexes. The XRD studies proved that crystallinity of chitosan has been diminished after Schiff base formation and metal complexation of L. Thermal and surface properties of the complexes have been also discussed from the investigation of their TG-DTG curves and SEM images, respectively. In addition, the catalytic efficiency of these complexes has been studied in the cyclohexane oxidation reaction using H2O2 as oxidant at 70 °C.

  8. Half-metallicity and ferromagnetism in penta-AlN2 nanostructure

    PubMed Central

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Liu, Haiying; Li, Shujuan; Zhao, Peng; Chen, Gang

    2016-01-01

    We have performed a detailed first-principles study of the penta-AlN2 nanostructure in the Cairo pentagonal tiling geometry, which is dynamically stable due to the absence of imaginary mode in the calculated phonon spectrum. The formation energy and the fragment cohesive energy analyses, the molecular dynamics simulations, and the mechanical property studies also support the structural stability. It could withstand the temperature as high as 1400 K and sustain the strain up to 16.1% against structural collapse. The slightly buckled penta-AlN2 is found to be a ferromagnetic semiconductor. The strain of ~9% could drive the structural transition from the buckled to the planar. Interestingly, the strain of >7% would change the conducting properties to show half-metallic characters. Furthermore, it could be also used to continuously enhance the magnetic coupling strength, rendering penta-AlN2 as a robust ferromagnetic material. These studies shed light on the possibilities in synthesizing penta-AlN2 and present many unique properties, which are worth of further studying on both theory and experiment. PMID:27616459

  9. Half-metallicity and ferromagnetism in penta-AlN2 nanostructure.

    PubMed

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Liu, Haiying; Li, Shujuan; Zhao, Peng; Chen, Gang

    2016-01-01

    We have performed a detailed first-principles study of the penta-AlN2 nanostructure in the Cairo pentagonal tiling geometry, which is dynamically stable due to the absence of imaginary mode in the calculated phonon spectrum. The formation energy and the fragment cohesive energy analyses, the molecular dynamics simulations, and the mechanical property studies also support the structural stability. It could withstand the temperature as high as 1400 K and sustain the strain up to 16.1% against structural collapse. The slightly buckled penta-AlN2 is found to be a ferromagnetic semiconductor. The strain of ~9% could drive the structural transition from the buckled to the planar. Interestingly, the strain of >7% would change the conducting properties to show half-metallic characters. Furthermore, it could be also used to continuously enhance the magnetic coupling strength, rendering penta-AlN2 as a robust ferromagnetic material. These studies shed light on the possibilities in synthesizing penta-AlN2 and present many unique properties, which are worth of further studying on both theory and experiment. PMID:27616459

  10. Half-metallicity and ferromagnetism in penta-AlN2 nanostructure

    NASA Astrophysics Data System (ADS)

    Li, Jiao; Fan, Xinyu; Wei, Yanpei; Liu, Haiying; Li, Shujuan; Zhao, Peng; Chen, Gang

    2016-09-01

    We have performed a detailed first-principles study of the penta-AlN2 nanostructure in the Cairo pentagonal tiling geometry, which is dynamically stable due to the absence of imaginary mode in the calculated phonon spectrum. The formation energy and the fragment cohesive energy analyses, the molecular dynamics simulations, and the mechanical property studies also support the structural stability. It could withstand the temperature as high as 1400 K and sustain the strain up to 16.1% against structural collapse. The slightly buckled penta-AlN2 is found to be a ferromagnetic semiconductor. The strain of ~9% could drive the structural transition from the buckled to the planar. Interestingly, the strain of >7% would change the conducting properties to show half-metallic characters. Furthermore, it could be also used to continuously enhance the magnetic coupling strength, rendering penta-AlN2 as a robust ferromagnetic material. These studies shed light on the possibilities in synthesizing penta-AlN2 and present many unique properties, which are worth of further studying on both theory and experiment.

  11. Crystal structure of bis-(N,N,N',N'-tetra-methyl-guanidinium) tetra-chlorido-cuprate(II).

    PubMed

    Ndiaye, Mamadou; Samb, Abdoulaye; Diop, Libasse; Maris, Thierry

    2016-07-01

    In the structure of the title salt, (C5H14N3)2[CuCl4], the Cu(II) atom in the anion lies on a twofold rotation axis. The tetra-chlorido-cuprate(II) anion adopts a flattened tetra-hedral coordination environment and inter-acts electrostatically with the tetra-methyl-guanidinium cation. The crystal packing is additionally consolidated through N-H⋯Cl and C-H⋯Cl hydrogen bonds, resulting in a three-dimensional network structure. PMID:27555960

  12. Extraction of Co(II) from aqueous solution using emulsion liquid membrane.

    PubMed

    Gasser, M S; El-Hefny, N E; Daoud, J A

    2008-03-01

    The extraction equilibrium of Co(II) from thiocyanate medium by CYANEX 923 (mixture of straight chain alkylated phosphine oxides) in cyclohexane was studied. The stoichiometry of the extraction reaction was postulated based on slope analysis method and the extraction constant Kex was calculated. The stripping percentage of Co(II) with sulphuric acid from the loaded CYANEX 923 was found to increase with the increase in acid concentration. The extraction of Co(II) from aqueous thiocyanate medium into emulsion liquid membrane using CYANEX 923 extractant was also studied. The influence of different parameters such as stirring speed, surfactant concentration, pH of the extractant phase, carrier concentration, internal phase stripping acid concentration, initial Co(II) concentration as well as temperature on the emulsion stability were investigated. The applicability of the emulsion liquid membrane (ELM) process using CYANEX 923 as extractant and SPAN 80 as surfactant for the removal and the concentration of Co(II) from thiocyanate solution was investigated. The results show that it is possible to recover 95% of cobalt in the inner phase after 10 min of contacting time with a concentration factor of 5.

  13. Tetra-amelia and splenogonadal fusion in Roberts syndrome

    SciTech Connect

    Ravel, T.J.L. de; Seftel, M.D.; Wright, C.A.

    1997-01-20

    Roberts-SC phocomelia syndrome comprises limb deficiencies of variable severity, facial clefts, and other anomalies. Tetra-amelia may also be associated with facial clefts and similar anomalies. We report on a female infant with severe tetra-amelia, micrognathia, cleft palate, splenogonadal fusion, and premature centromere separation. We propose that this represents the severe expression of the Roberts-SC phocomelia syndrome. 18 refs., 6 figs.

  14. 3,3-Dimethyl-1,2,3,4-tetra­hydro­cyclo­penta­[b]indole-1,2-dione (bruceolline E)

    PubMed Central

    Jordon, Jason A.; Badenock, Jeanese C.; Gribble, Gordon W.; Jasinski, Jerry P.; Golen, James A.

    2012-01-01

    The title compound, C13H11NO2, crystallizes with two mol­ecules in the asymmetric unit. The crystal packing is stabilized by N—H⋯O hydrogen bonds, which link the mol­ecules into chains along [10], and weak C—H⋯O inter­actions. PMID:22346990

  15. Tetra­pyrazine­platinum(II) bis­(tetra­fluoro­borate) acetonitrile hemisolvate

    PubMed Central

    Derry, Paul J.; Wang, Xiaoping; Smucker, Bradley W.

    2008-01-01

    The improved synthesis and characterization of tetra­pyrazine­platinum(II) bis­(tetra­fluoro­borate) acetonitrile hemisolvate, [Pt(C4H4N2)4](BF4)2·0.5CH3CN, is reported. The unit cell contains a half equivalent of an acetonitrile solvent mol­ecule per tetra­pyrazine­platinum(II) ion. The coordination geometry of the PtII ion is almost square-planar, with the Pt atom residing on an inversion center. The BF4 − counter-anion, located at a general position, has an idealized tetra­hedral geometry and an acetonitrile solvent mol­ecule, the methyl group of which is disordered over two equal positions, sits on a twofold rotation axis. PMID:21580888

  16. Sorption Characteristics of Aqueous Co(II) on Preformed Iron Ferrite Impregnated into Phenolsulphonic Formaldehyde Resin

    SciTech Connect

    Lee, K. J.; Kim, Y. K.

    2002-02-26

    A series of stepwise procedures to prepare a new organic-inorganic composite magnetic resin with phenolsulphonicformaldehyde and freshly formed iron ferrite was established, based upon wet-and-neutralization method for synthesizing iron ferrite and pearl-polymerization method for synthesizing rigid bead-type composite resin. The composite resin prepared by the above method shows stably high removal efficiency (maximally over 3.1 meq./gresin) to Co(II) species from wastewater in a wide range of solution pH. The wide range of applicable solution pH (i.e. pH 4.09 to 10.32) implies that the composite resin overcomes the limitations of the conventional ferrite process that is practically applicable only to alkaline conditions. It has been found that both ion exchange (by the organic resin constituent) and surface adsorption (by the inorganic adsorbent constituent) are major reaction mechanisms for removing Co(II) from wastewater, but surface precipitation results in the high sorption capacity to Co(II) beyond normal ion exchange capacity of the phenolsulphonic-formaldehyde resin. Standard enthalpy change derived from van't Hoff equation is 32.0 kJ{center_dot}mol-1 conforming to the typical range for chemisorption or ion exchange. In a wide range of equilibrium Co(II) concentration, the overall isotherm is qualitatively explained by the generalized adsorption isotherm concept proposed by McKinley. At the experimental conditions where the composite resin shows equivalent selectivity to Co(II) and other competing reagents (i.e. EDTA and Na), the ratios of Co(II) to other chemicals turn out to be 2:1 and 1:221, respectively. In addition, the selectivity of the PSF-F to Co(II) species is very high (about 72% of Co(II)-removal efficiency) even when the molar ratio of Co(II) to Ca(II) is 1:30. It is anticipated that the composite resin can also be used for column-operation with process-control by applying external magnetic field, since the rigid bead-type composite resin shows

  17. Tripodal phenylamine-based ligands and their CoII complexes.

    PubMed

    Jones, Matthew B; MacBeth, Cora E

    2007-10-01

    The syntheses of two phenylamine-based ligand systems, N(o-PhNH(2))(3) and N(o-PhNHC(O)(i)Pr)(3), are reported. These ligands readily coordinate to Co(II) to form monomeric complexes. X-ray diffraction studies establish that the [N(o-PhNC(O)(i)Pr)(3)](3-) ligand stabilizes the Co(II) ion in a trigonal-monopyramidal coordination environment. The axial coordination site in this complex is accessible and, upon cyanide coordination, generates an electrochemically active species.

  18. Ethyl-enedi-ammonium sodium tetra-kis-[bis-(ethyl-enedi-amine-κ(2) N,N')(oxalato-κ(2) O (1),O (2))cobalt(III)] [penta-hydrogen di(phosphato-octa-deca-tungstate)] tetra-deca-hydrate.

    PubMed

    Zhang, Shuzhuo; Wang, Jing; Xu, Yun

    2013-10-16

    The title compound, Na(C2H10N2)[Co(C2O4)(C2H8N2)2]4[H5(P2W18O62)2]·14H2O, prepared under hydro-thermal conditions, consists of two Dawson-type [P2W18O62](6-) anions, four isolated [Co(en)2(ox)](+) cations (en = ethyl-enedi-amine and ox = oxalate), one Na(+) cation, one [H2en](2+) cation, and a number of ordered (14) and disordered solvent water mol-ecules. The [P2W18O62](6-) polyoxidometalate anion has site symmetry 1 and contains two structurally distinct types of W atoms: viz. six W atoms on vertical pseudo-mirror planes grouped in two sets of three, and 12 equatorial W atoms that do not lie in the pseudo-mirror planes grouped in two sets of six. In each [Co(en)2(ox)](+) cation, the Co(III) ion is coordinated by four N atoms from two en ligands and two O atoms from the ox ligands, completing a distorted octa-hedral structure. The sodium cation lies on an inversion centre and additionally links the complex cations and anions. In the crystal, the various units are linked by N-H⋯O and O-H⋯O hydrogen bonds, which together with C-H⋯O hydrogen bonds form a three-dimensional structure. The contribution of a region of disordered electron density, possibly highly disordered solvent water mol-ecules, to the scattering was removed with the SQUEEZE option of PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. To equilibrate the charges five H(+) ions have been added to the polyoxidometalate. These H(+) ions and the disordered solvent contribution were not included in the reported mol-ecular weight and density. PMID:24454036

  19. Crystal structure and magnetic properties of a linear tetranuclear Co(II) cluster.

    PubMed

    Wang, Yingying; Wen, Meixia; Gao, Zhongjun; Sheng, Ning

    2016-09-01

    Polynuclear complexes are an important class of inorganic functional materials and are of interest particularly for their applications in molecular magnets. Multidentate chelating ligands play an important role in the design and syntheses of polynuclear metal clusters. A novel linear tetranuclear Co(II) cluster, namely bis{μ3-(E)-2-[(2-oxidobenzylidene)amino]phenolato}bis{μ2-(E)-2-[(2-oxidobenzylidene)amino]phenolato}bis(1,10-phenanthroline)tetracobalt(II), [Co4(C14H11NO2)4(C12H8N2)2], was prepared under solvothermal conditions through a mixed-ligand synthetic strategy. The structure was determined by X-ray single-crystal diffraction and bulk purity was confirmed by powder X-ray diffraction. The complex molecule has a centrosymmetric tetranuclear chain-like structure and the four Co(II) ions are located in two different coordination environments. The Co(II) ions at the ends of the chain are in a slightly distorted octahedral geometry, while the two inner Co(II) ions are in five-coordinate distorted trigonal bipyramidal environments. A magnetic study reveals ferromagnetic Co(II)...Co(II) exchange interactions for the complex. PMID:27585934

  20. Adsorption of Co(II) by a carboxylate-functionalized polyacrylamide grafted lignocellulosics.

    PubMed

    Shibi, I G; Anirudhan, T S

    2005-02-01

    A new adsorbent (PGBS-COOH) having carboxylate functional group at the chain end was synthesized by graft copolymerization of acrylamide onto banana stalk, BS (Musa Paradisiaca) using ferrous ammonium sulphate/H2O2 redox initiator system. The efficiency of the adsorbent in the removal of cobalt [Co(II)] from water was investigated using batch adsorption technique. The adsorbent exhibits very high adsorption potential for Co(II) and under optimum conditions more than 99% removal was achieved. The maximum adsorption capacity was observed at the pH range 6.5-9.0. The equilibrium isotherm data were analysed using three isotherm models, Langmuir, Freundlich and Scatchard, to determine the best fit equation for the sorption of Co(II) on the PGBS-COOH. A comparative study with a commercial cation exchanger, Ceralite IRC-50, having carboxylate functional group showed that PGBS-COOH is 2.8 times more effective compared to Ceralite IRC-50 at 30 degrees C. Synthetic nuclear power plant coolant water samples were also treated by the adsorbent to demonstrate its efficiency in removing Co(II) from water in the presence of other metal ions. Acid regeneration was tried for several cycles to recover the adsorbed metal ions and also to restore the sorbent to its original state.

  1. 40 CFR 721.10679 - Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester (generic). 721.10679 Section 721... Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester... identified generically as carboxylic acid, substituted alkylstannylene ester, reaction products...

  2. Impaired ergosterol biosynthesis mediated fungicidal activity of Co(II) complex with ligand derived from cinnamaldehyde.

    PubMed

    Shreaz, Sheikh; Shiekh, Rayees A; Raja, Vaseem; Wani, Waseem A; Behbehani, Jawad M

    2016-03-01

    In this study, we have used aldehyde function of cinnamaldehyde to synthesize N, N'-Bis (cinnamaldehyde) ethylenediimine [C20H20N2] and Co(II) complex of the type [Co(C40H40N4)Cl2]. The structures of the synthesized compounds were determined on the basis of physiochemical analysis and spectroscopic data ((1)H NMR, FTIR, UV-visible and mass spectra) along with molar conductivity measurements. Anticandidal activity of cinnamaldehyde its ligand [L] and Co(II) complex was investigated by determining MIC80, time-kill kinetics, disc diffusion assay and ergosterol extraction and estimation assay. Ligand [L] and Co(II) complex are found to be 4.55 and 21.0 folds more efficient than cinnamaldehyde in a liquid medium. MIC80 of Co(II) complex correlated well with ergosterol inhibition suggesting ergosterol biosynthesis to be the primary site of action. In comparison to fluconazole, the test compounds showed limited toxicity against H9c2 rat cardiac myoblasts. In confocal microscopy propidium iodide (PI) penetrates the yeast cells when treated with MIC of metal complex, indicating a disruption of cell membrane that results in imbibition of dye. TEM analysis of metal complex treated cells exhibited notable alterations or damage to the cell membrane and the cell wall. The structural disorganization within the cell cytoplasm was noted. It was concluded that fungicidal activity of Co(II) complex originated from loss of membrane integrity and a decrease in ergosterol content is only one consequence of this.

  3. Tetra­butyl­ammonium butyl­tetra­chlorido­stannate(IV)

    PubMed Central

    Diop, Tidiane; van der Lee, Arie; Diop, Libasse

    2013-01-01

    In the title compound, [N(C4H9)4][Sn(C4H9)Cl4], the SnIV atom of the stannate anion has a trigonal-bipyramidal coordination sphere by two Cl atoms and one butyl chain in the equatorial plane and by two Cl atoms in the apical positions. Two of the four butyl chains of the tetra­butyl­ammonium cation are partially disordered, each with refined site occupancies of 0.691 (6):0.309 (6). Weak C—H⋯Cl hydrogen-bonding inter­actions help to consolidate the crystal packing, as well as a short Cl⋯Cl inter­action of 3.295 (2) Å. PMID:24098187

  4. [μ-6,9-Bis(carboxylatomethyl)-3,12-bis(car­boxymethyl)-3,6,9,12-tetraaza­tetradecanedioato]bis­[aqua­cobalt(II)] tetra­hydrate

    PubMed Central

    Qian, Qi-feng; Wu, Jin-hui; Qian, Jin-liang

    2013-01-01

    The binuclear title complex, [Co2(C18H26N4O12)(H2O)2]·4H2O, lies about a centre of inversion, the CoII atom being coordinated in a distorted octa­hedral arrangement defined by one water mol­ecule and N2O3 donors derived from one end of a 6,9-bis(carboxylatomethyl)-3,12-bis(car­boxy­methyl)-3,6,9,12-tetraaza­tetradecanedioate (H2TTHA4−) tetra­anion. In the crystal, numerous O—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network. PMID:23424439

  5. [μ-6,9-Bis(carboxylatomethyl)-3,12-bis(car-boxymethyl)-3,6,9,12-tetraaza-tetradecanedioato]bis-[aqua-cobalt(II)] tetra-hydrate.

    PubMed

    Qian, Qi-Feng; Wu, Jin-Hui; Qian, Jin-Liang

    2013-02-01

    The binuclear title complex, [Co(2)(C(18)H(26)N(4)O(12))(H(2)O)(2)]·4H(2)O, lies about a centre of inversion, the Co(II) atom being coordinated in a distorted octa-hedral arrangement defined by one water mol-ecule and N(2)O(3) donors derived from one end of a 6,9-bis(carboxylatomethyl)-3,12-bis(car-boxy-methyl)-3,6,9,12-tetraaza-tetradecanedioate (H(2)TTHA(4-)) tetra-anion. In the crystal, numerous O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. PMID:23424439

  6. Crystal structure of the tetra-gonal polymorph of bis-(1-ethyl-3-methyl-imidazolium) tetra-bromido-cadmate.

    PubMed

    Đorđević, Tamara; Gerger, Sabrina; Karanović, Ljiljana

    2016-07-01

    Both unique Cd atoms in the tetra-gonal polymorph of bis-(1-ethyl-3-methyl-imidazolium) tetra-bromido-cadmate, (C6H11N2)2[CdBr4], occupy special positions (site symmetry -4). The crystal structure consists of isolated tetra-hedral [CdBr4](2-) anions which are surrounded by 1-ethyl-3-methyl-imidazolium cations. The methyl and ethyl side chains of the cations show positional disorder in a 0.590 (11):0.410 (11) ratio. In the crystal, (C6H11N2)(+) cations display three weak C-H⋯Br hydrogen-bond inter-actions through the imidazolium ring H atoms with the Br(-) ligands of the surrounding complex anions. The alkyl groups of the side chains are not involved in hydrogen bonding. PMID:27555953

  7. Spectroscopic properties of a series of Co(II) coordination polymers and the influence of Co(II) coordination environment on photoelectric property

    NASA Astrophysics Data System (ADS)

    Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun

    2015-02-01

    Four Co(II) coordination polymers, [Co(suc)]n1, [Co(pdc)]n2, {[Co7(suc)4(OH)6(H2O)3] · 8H2O}n3, {[Co(bdc)(phen)(H2O)] · H2O}n4 (H2suc = succinic acid, H2pdc = pyridine-3,4-dicarboxylic acid, H2bdc = 1,2-benzenedicarboxylic acid, phen = 1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc2- and pdc2- anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc2- anions bridging seven-nuclear [Co7(OH)6(H2O)3]3- unit and polymer 4 is a 1D structure bridged by bdc2- anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed.

  8. Spectroscopic properties of a series of Co(II) coordination polymers and the influence of Co(II) coordination environment on photoelectric property.

    PubMed

    Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun

    2015-02-25

    Four Co(II) coordination polymers, [Co(suc)]n 1, [Co(pdc)]n 2, {[Co7(suc)4(OH)6(H2O)3]·8H2O}n 3, {[Co(bdc)(phen)(H2O)]·H2O}n 4 (H2suc=succinic acid, H2pdc=pyridine-3,4-dicarboxylic acid, H2bdc=1,2-benzenedicarboxylic acid, phen=1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc(2-) and pdc(2-) anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc(2-) anions bridging seven-nuclear [Co7(OH)6(H2O)3](3-) unit and polymer 4 is a 1D structure bridged by bdc(2-) anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed.

  9. Spectroscopic properties of a series of Co(II) coordination polymers and the influence of Co(II) coordination environment on photoelectric property.

    PubMed

    Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun

    2015-02-25

    Four Co(II) coordination polymers, [Co(suc)]n 1, [Co(pdc)]n 2, {[Co7(suc)4(OH)6(H2O)3]·8H2O}n 3, {[Co(bdc)(phen)(H2O)]·H2O}n 4 (H2suc=succinic acid, H2pdc=pyridine-3,4-dicarboxylic acid, H2bdc=1,2-benzenedicarboxylic acid, phen=1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc(2-) and pdc(2-) anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc(2-) anions bridging seven-nuclear [Co7(OH)6(H2O)3](3-) unit and polymer 4 is a 1D structure bridged by bdc(2-) anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed. PMID:25280332

  10. Induction of apoptosis by penta-O-galloyl-beta-D-glucose through activation of caspase-3 in human leukemia HL-60 cells.

    PubMed

    Pan, M H; Lin, J H; Lin-Shiau, S Y; Lin, J K

    1999-09-24

    Penta-O-galloyl-beta-D-glucose is structurally related to (-)-epigallocatechin gallate and is isolated from hydrolyzed tannin. Penta-O-galloyl-beta-D-glucose can inhibit tumor promotion by teleocidin. We investigated the effects of penta-O-galloyl-beta-D-glucose and various tea polyphenols on cell viability in human leukemia HL-60 cells. In this study, we demonstrated that penta-O-galloyl-beta-D-glucose was able to induce apoptosis in a concentration- and time-dependent manner; however, other polyphenols were less effective. We further investigated the molecular mechanisms of penta-O-galloyl-beta-D-glucose-induced apoptosis. Treatment with penta-O-galloyl-beta-D-glucose caused induction of caspase-3/CPP32 activity in dose- and time-dependent manner, but not caspase-1 activity, and induced the degradation of poly-(ADP-ribose) polymerase. Pretreatment with acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO) and Z-Val-Ala-Asp-fluoromethyl-ketone (Z-VAD-FMK) inhibited penta-O-galloyl-beta-D-glucose-induced DNA fragmentation. Furthermore, treatment with penta-O-galloyl-beta-D-glucose (50 microM) caused a rapid loss of mitochondrial transmembrane potential, release of mitochondrial cytochrome c into cytosol, and subsequent induction of procaspase-9 processing. Our results indicate that penta-O-galloyl-beta-D-glucose allows caspase-activated deoxyribonuclease to enter the nucleus and degrade chromosomal DNA, and induces DFF-45 (DNA fragmentation factor) degradation. These results lead to a working hypothesis that penta-O-galloyl-beta-D-glucose-induced apoptosis is triggered by the release of cytochrome c into the cytosol, procaspase-9 processing, activation of caspase-3, degradation of poly-(ADP-ribose) polymerase, and DNA fragmentation caused by the caspase-activated deoxyribonuclease through the digestion of DFF-45. The induction of apoptosis by penta-O-galloyl-beta-D-glucose may provide a pivotal mechanism for its cancer chemopreventive action.

  11. 1,1,4,7,7-Penta­methyl­diethylenetri­ammonium trinitrate

    PubMed Central

    Gatfaoui, Sofian; Rzaigui, Mohamed; Marouani, Houda

    2014-01-01

    In the title compound, C9H26N3 3+·3NO3 −, the triprotonated 1,1,4,7,7-penta­methyl­diethylenetri­amine mol­ecules are linked to the nitrate anions by multiple bifurcated N—H⋯(O,O) and weak C—H⋯O hydrogen bonds. The organic cation is characterized by N—C—C—N torsion angles of −176.2 (2) and 176.6 (2)°. PMID:24764908

  12. Penta-hepta defect chaos in a model for rotating hexagonal convection.

    PubMed

    Young, Yuan-Nan; Riecke, Hermann

    2003-04-01

    In a model for rotating non-Boussinesq convection with mean flow, we identify a regime of spatiotemporal chaos that is based on a hexagonal planform and is sustained by the induced nucleation of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlations between the defects in the form of density-dependent creation and annihilation rates of defects. We extract these rates from the distribution function and also directly from the defect dynamics.

  13. Diadenosine tetra- and pentaphosphates affect contractility and bioelectrical activity in the rat heart via P2 purinergic receptors.

    PubMed

    Pustovit, Ksenia B; Kuzmin, Vladislav S; Abramochkin, Denis V

    2016-03-01

    Diadenosine polyphosphates (Ap(n)As) are endogenously produced molecules which have been identified in various tissues of mammalian organism, including myocardium. Ap(n)As contribute to the blood clotting and are also widely accepted as regulators of blood vascular tone. Physiological role of Ap(n)As in cardiac muscle has not been completely elucidated. The present study aimed to investigate the effects of diadenosine tetra- (Ap4A) and penta- (Ap5A) polyphosphates on contractile function and action potential (AP) waveform in rat supraventricular and ventricular myocardium. We have also demonstrated the effects of A4pA and Ap5A in myocardial sleeves of pulmonary veins (PVs), which play a crucial role in genesis of atrial fibrillation. APs were recorded with glass microelectrodes in multicellular myocardial preparations. Contractile activity was measured in isolated Langendorff-perfused rat hearts. Both Ap4A and Ap5A significantly reduced contractility of isolated Langendorff-perfused heart and produced significant reduction of AP duration in left and right auricle, interatrial septum, and especially in right ventricular wall myocardium. Ap(n)As also shortened APs in rat pulmonary veins and therefore may be considered as potential proarrhythmic factors. Cardiotropic effects of Ap4A and Ap5A were strongly antagonized by selective blockers of P2 purine receptors suramin and pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS), while P1 blocker DPCPX was not effective. We conclude that Ap(n)As may be considered as new class of endogenous cardioinhibitory compounds. P2 purine receptors play the central role in mediation of Ap4A and Ap5A inhibitory effects on electrical and contractile activity in different regions of the rat heart. PMID:26680209

  14. Breathing mode vibrations and elastic properties of single-crystal and penta-twinned gold nanorods.

    PubMed

    Gan, Yong; Sun, Zheng; Chen, Zhen

    2016-08-10

    The acoustic vibrations of individual single-crystal and penta-twinned gold nanorods with widths from ∼7 to ∼26 nm are studied using atomic-level simulations and finite element calculations. It is demonstrated that the continuum model in the limit of an infinite rod length could be used to describe the breathing periods of nanorods with an aspect ratio as small as ∼2.5, in combination with bulk material elastic constants. The elastic moduli of gold nanorods are determined via their atomistically simulated extensional periods and the dispersion relation based on long-wavelength approximation. The twinned nanorods become stiffer as the width is reduced, which is in contrast to the size dependence of the modulus in single-crystal nanorods. Further finite element calculations for the breathing periods of nanorods are performed using isotropic elastic constants of bulk gold. We find that the breathing vibrations of the penta-twinned nanorods are more affected by the crystal structure effect than those of single-crystal nanorods, because a smaller range of crystal directions perpendicular to the long axis is involved in the breathing vibrations of twinned nanorods.

  15. Indirect Oxidation of Co(II) in the Presence of the Marine Mn(II)-Oxidizing Bacterium Bacillus Sp. Strain SG-1

    SciTech Connect

    Murray, K.J.; Webb, S.M.; Bargar, J.R.; Tebo, B.M.; /Scripps Inst. Oceanography /SLAC, SSRL /Oregon Health Sci. U.

    2009-04-29

    Cobalt(II) oxidation in aquatic environments has been shown to be linked to Mn(II) oxidation, a process primarily mediated by bacteria. This work examines the oxidation of Co(II) by the spore-forming marine Mn(II)-oxidizing bacterium Bacillus sp. strain SG-1, which enzymatically catalyzes the formation of reactive nanoparticulate Mn(IV) oxides. Preparations of these spores were incubated with radiotracers and various amounts of Co(II) and Mn(II), and the rates of Mn(II) and Co(II) oxidation were measured. Inhibition of Mn(II) oxidation by Co(II) and inhibition of Co(II) oxidation by Mn(II) were both found to be competitive. However, from both radiotracer experiments and X-ray spectroscopic measurements, no Co(II) oxidation occurred in the complete absence of Mn(II), suggesting that the Co(II) oxidation observed in these cultures is indirect and that a previous report of enzymatic Co(II) oxidation may have been due to very low levels of contaminating Mn. Our results indicate that the mechanism by which SG-1 oxidizes Co(II) is through the production of the reactive nanoparticulate Mn oxide.

  16. Penta-substituted benzimidazoles as potent antagonists of the calcium-sensing receptor (CaSR-antagonists).

    PubMed

    Gerspacher, Marc; Altmann, Eva; Beerli, René; Buhl, Thomas; Endres, Ralf; Gamse, Rainer; Kameni-Tcheudji, Jacques; Kneissel, Michaela; Krawinkler, Karl Heinz; Missbach, Martin; Schmidt, Alfred; Seuwen, Klaus; Weiler, Sven; Widler, Leo

    2010-09-01

    A series of novel benzimidazole derivatives has been designed via a scaffold morphing approach based on known calcilytics chemotypes. Subsequent lead optimisation led to the discovery of penta-substituted benzimidazoles that exhibit attractive in vitro and in vivo calcium-sensing receptor (CaSR) inhibitory profiles. In addition, synthesis and structure-activity relationship data are provided.

  17. Solid dispersions of the penta-ethyl ester prodrug of diethylenetriaminepentaacetic acid (DTPA): Formulation design and optimization studies

    PubMed Central

    Yang, Yu-Tsai; Di Pasqua, Anthony J.; Zhang, Yong; Sueda, Katsuhiko; Jay, Michael

    2015-01-01

    The penta-ethyl ester prodrug of diethylenetriaminepentaacetic acid (DTPA), which exists as an oily liquid, was incorporated into a solid dispersion for oral administration by the solvent evaporation method using blends of polyvinylpyrrolidone (PVP), Eudragit® RL PO and α-tocopherol. D-optimal mixture design was used to optimize the formulation. Formulations that had a high concentration of both Eudragit® RL PO and α-tocopherol exhibited low water absorption and enhanced stability of the DTPA prodrug. Physicochemical properties of the optimal formulation were evaluated using Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). In vitro release of the prodrug was evaluated using the USP Type II apparatus dissolution method. DSC studies indicated that the matrix had an amorphous structure, while FTIR spectrometry showed that DTPA penta-ethyl ester and excipients did not react with each other during formation of the solid dispersion.. Dissolution testing showed that the optimized solid dispersion exhibited a prolonged release profile, which could potentially result in a sustained delivery of DTPA penta-ethyl to enhance bioavailability. In conclusion, DTPA penta-ethyl ester was successfully incorporated into a solid matrix with high drug loading and improved stability compared to prodrug alone. PMID:24047113

  18. Measurement of cone beam CT coincidence with megavoltage isocentre and image sharpness using the QUASAR Penta-Guide phantom.

    PubMed

    Sykes, J R; Lindsay, R; Dean, C J; Brettle, D S; Magee, D R; Thwaites, D I

    2008-10-01

    For image-guided radiotherapy (IGRT) systems based on cone beam CT (CBCT) integrated into a linear accelerator, the reproducible alignment of imager to x-ray source is critical to the registration of both the x-ray-volumetric image with the megavoltage (MV) beam isocentre and image sharpness. An enhanced method of determining the CBCT to MV isocentre alignment using the QUASAR Penta-Guide phantom was developed which improved both precision and accuracy. This was benchmarked against our existing method which used software and a ball-bearing (BB) phantom provided by Elekta. Additionally, a method of measuring an image sharpness metric (MTF(50)) from the edge response function of a spherical air cavity within the Penta-Guide phantom was developed and its sensitivity was tested by simulating misalignments of the kV imager. Reproducibility testing of the enhanced Penta-Guide method demonstrated a systematic error of <0.2 mm when compared to the BB method with near equivalent random error (s=0.15 mm). The mean MTF(50) for five measurements was 0.278+/-0.004 lp mm(-1) with no applied misalignment. Simulated misalignments exhibited a clear peak in the MTF(50) enabling misalignments greater than 0.4 mm to be detected. The Penta-Guide phantom can be used to precisely measure CBCT-MV coincidence and image sharpness on CBCT-IGRT systems.

  19. Novel and High Volume Use Flame Retardants in US Couches Reflective of the 2005 PentaBDE Phase Out

    PubMed Central

    2012-01-01

    California’s furniture flammability standard Technical Bulletin 117 (TB 117) is believed to be a major driver of chemical flame retardant (FR) use in residential furniture in the United States. With the phase-out of the polybrominated diphenyl ether (PBDE) FR mixture PentaBDE in 2005, alternative FRs are increasingly being used to meet TB 117; however, it was unclear which chemicals were being used and how frequently. To address this data gap, we collected and analyzed 102 samples of polyurethane foam from residential couches purchased in the United States from 1985 to 2010. Overall, we detected chemical flame retardants in 85% of the couches. In samples purchased prior to 2005 (n = 41) PBDEs associated with the PentaBDE mixture including BDEs 47, 99, and 100 (PentaBDE) were the most common FR detected (39%), followed by tris(1,3-dichloroisopropyl) phosphate (TDCPP; 24%), which is a suspected human carcinogen. In samples purchased in 2005 or later (n = 61) the most common FRs detected were TDCPP (52%) and components associated with the Firemaster550 (FM 550) mixture (18%). Since the 2005 phase-out of PentaBDE, the use of TDCPP increased significantly. In addition, a mixture of nonhalogenated organophosphate FRs that included triphenyl phosphate (TPP), tris(4-butylphenyl) phosphate (TBPP), and a mix of butylphenyl phosphate isomers were observed in 13% of the couch samples purchased in 2005 or later. Overall the prevalence of flame retardants (and PentaBDE) was higher in couches bought in California compared to elsewhere, although the difference was not quite significant (p = 0.054 for PentaBDE). The difference was greater before 2005 than after, suggesting that TB 117 is becoming a de facto standard across the U.S. We determined that the presence of a TB 117 label did predict the presence of a FR; however, lack of a label did not predict the absence of a flame retardant. Following the PentaBDE phase out, we also found an increased number of flame retardants on

  20. Mechanism of Co(II) adsorption by zero valent iron/graphene nanocomposite.

    PubMed

    Xing, Min; Xu, Lejin; Wang, Jianlong

    2016-01-15

    Nanoscale zero valent iron (ZVI)/graphene (GF) composite was prepared and characterized by Brunauer-Emmett-Teller (BET) surface area measurement and zeta potential determination. The adsorption isotherm of Co(II) in aqueous solution, as well as the influence of pH values and ionic strengths was studied. The mechanism of Co(II) adsorption by GF was investigated through analyzing the sorption products at initial pH of 3.0, 6.0 and 9.0 using high-resolution transmission electron microscope with energy dispersive X-ray detector (HRTEM-EDX), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), Raman spectra, X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) measurement. The results indicated that Langmuir isotherm model fitted well and the adsorption capacity was 131.58 mg g(-1) at 30°C. Adsorption capacity was not significantly influenced by ionic strength and kept high at pH 4.0∼9.0. The detail information of GF-Co interaction at different initial pH values was obtained using XAFS analysis combined with other characterization methods. Coordination numbers (CN) and interatomic distances (R) of both Fe and Co were given. At pH 3.0 and pH 6.0, the Co-substituted iron oxides transformed to CoFe2O4-like structure, while at pH 9.0 they changed to green rust-like phases. Co occupied preferentially in the octahedral sites in acid solution. The adsorption mechanism of Co(II) was attributed to inner-sphere complexation and dissolution/re-precipitation of the substituted metal oxides. PMID:26368802

  1. Mechanism of Co(II) adsorption by zero valent iron/graphene nanocomposite.

    PubMed

    Xing, Min; Xu, Lejin; Wang, Jianlong

    2016-01-15

    Nanoscale zero valent iron (ZVI)/graphene (GF) composite was prepared and characterized by Brunauer-Emmett-Teller (BET) surface area measurement and zeta potential determination. The adsorption isotherm of Co(II) in aqueous solution, as well as the influence of pH values and ionic strengths was studied. The mechanism of Co(II) adsorption by GF was investigated through analyzing the sorption products at initial pH of 3.0, 6.0 and 9.0 using high-resolution transmission electron microscope with energy dispersive X-ray detector (HRTEM-EDX), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), Raman spectra, X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) measurement. The results indicated that Langmuir isotherm model fitted well and the adsorption capacity was 131.58 mg g(-1) at 30°C. Adsorption capacity was not significantly influenced by ionic strength and kept high at pH 4.0∼9.0. The detail information of GF-Co interaction at different initial pH values was obtained using XAFS analysis combined with other characterization methods. Coordination numbers (CN) and interatomic distances (R) of both Fe and Co were given. At pH 3.0 and pH 6.0, the Co-substituted iron oxides transformed to CoFe2O4-like structure, while at pH 9.0 they changed to green rust-like phases. Co occupied preferentially in the octahedral sites in acid solution. The adsorption mechanism of Co(II) was attributed to inner-sphere complexation and dissolution/re-precipitation of the substituted metal oxides.

  2. Penta-terbium lithium tris-tannide, Tb(5)LiSn(3).

    PubMed

    Stetskiv, Andrij; Tarasiuk, Ivan; Misztal, Renata; Pavlyuk, Volodymyr

    2011-11-01

    The new ternary phase penta-terbium lithium tris-tannide, Tb(5)LiSn(3), crystallizes in the hexa-gonal Hf(5)CuSn(3) structure type, which is a 'filled' version of the binary RE(5)Sn(3) phases (Mn(5)Si(3)-type) (RE is rare earth). The asymmetric unit contains two Tb sites (site symmetries 3.2 and m2m), one Li site (site symmetry [Formula: see text].m) and one Sn site (site symmetry m2m). The 14-vertex Frank-Kasper polyhedra are typical for Li and Tb atoms. The environment of the Sn atom is a pseudo-Frank-Kasper polyhedron with a coordination number of 13 for the tin atom. One of the Tb atoms is enclosed in a 17-vertex polyhedron. The metallic type of bonding was indicated by an analysis of the inter-atomic distances.

  3. Penta­terbium lithium tris­tannide, Tb5LiSn3

    PubMed Central

    Stetskiv, Andrij; Tarasiuk, Ivan; Misztal, Renata; Pavlyuk, Volodymyr

    2011-01-01

    The new ternary phase penta­terbium lithium tris­tannide, Tb5LiSn3, crystallizes in the hexa­gonal Hf5CuSn3 structure type, which is a ‘filled’ version of the binary RE 5Sn3 phases (Mn5Si3-type) (RE is rare earth). The asymmetric unit contains two Tb sites (site symmetries 3.2 and m2m), one Li site (site symmetry .m) and one Sn site (site symmetry m2m). The 14-vertex Frank–Kasper polyhedra are typical for Li and Tb atoms. The environment of the Sn atom is a pseudo-Frank–Kasper polyhedron with a coordination number of 13 for the tin atom. One of the Tb atoms is enclosed in a 17-vertex polyhedron. The metallic type of bonding was indicated by an analysis of the inter­atomic distances. PMID:22219726

  4. Hydrogenation of Penta-Graphene Leads to Unexpected Large Improvement in Thermal Conductivity.

    PubMed

    Wu, Xufei; Varshney, Vikas; Lee, Jonghoon; Zhang, Teng; Wohlwend, Jennifer L; Roy, Ajit K; Luo, Tengfei

    2016-06-01

    Penta-graphene (PG) has been identified as a novel two-dimensional (2D) material with an intrinsic bandgap, which makes it especially promising for electronics applications. In this work, we use first-principles lattice dynamics and iterative solution of the phonon Boltzmann transport equation (BTE) to determine the thermal conductivity of PG and its more stable derivative, hydrogenated penta-graphene (HPG). As a comparison, we also studied the effect of hydrogenation on graphene thermal conductivity. In contrast to hydrogenation of graphene, which leads to a dramatic decrease in thermal conductivity, HPG shows a notable increase in thermal conductivity, which is much higher than that of PG. Considering the necessity of using the same thickness when comparing thermal conductivity values of different 2D materials, hydrogenation leads to a 63% reduction in thermal conductivity for graphene, while it results in a 76% increase for PG. The high thermal conductivity of HPG makes it more thermally conductive than most other semiconducting 2D materials, such as the transition metal chalcogenides. Our detailed analyses show that the primary reason for the counterintuitive hydrogenation-induced thermal conductivity enhancement is the weaker bond anharmonicity in HPG than PG. This leads to weaker phonon scattering after hydrogenation, despite the increase in the phonon scattering phase space. The high thermal conductivity of HPG may inspire intensive research around HPG and other derivatives of PG as potential materials for future nanoelectronic devices. The fundamental physics understood from this study may open up a new strategy to engineer thermal transport properties of other 2D materials by controlling bond anharmonicity via functionalization.

  5. Separation and extraction of Co(II) using magnetic chitosan nanoparticles grafted with β-cyclodextrin and determination by FAAS

    NASA Astrophysics Data System (ADS)

    Moghimi, Ali

    2014-12-01

    A novel and selective method for the fast determination of trace amounts of Co(II) ions in water samples has been developed. The procedure is based on the selective sorption of Co(II) ions using magnetic chitosan nanoparticles grafted with β-cyclodextrin at different pH followed by elution with organic eluents and determination by atomic absorption spectrometry The preconcentration factor was 100 (1 mL elution volume) for a 100 mL sample volume. The limit of detection of the proposed method is 1.0 ng mL-1. The maximum sorption capacity of sorbent under optimum conditions has been found to be 5 mg of Co per gram of sorbent. The relative standard deviation under optimum conditions was 3.0% ( n = 10). Accuracy and applicability of the method was estimated using test samples of natural and model water with different amounts of Co(II).

  6. Gel-liquid extraction and separation of U(VI), Th(IV), Ce(III), and Co(II)

    SciTech Connect

    Shakir, K.; Beheir, S.G.

    1980-01-01

    The gel-liquid extraction of U(VI), Th(IV), Ce(III), and Co(II) has been investigated in the 0.01 to 2 M HNO/sub 3/ range using a gel prepared by swelling styrene divinylbenzene with di-(2-ethylhexyl)phosphoric acid. Obtained results indicate that all of the tested cations can be extracted and that the extraction coefficients increase in the order Ce(III) < Co(II) < Th(IV) < U(VI) and generally decrease with acidity. Under suitable conditions, separation of Th(IV), Ce(III), or Co(II) from U(VI) or of Th(IV) from Ce(III) can be achieved. Kinetic studies indicate that the extraction process is controlled by a progressive shell sorption mechanism. 10 figures, 3 tables

  7. Sequence analysis of a few species of termites (Order: Isoptera) on the basis of partial characterization of COII gene.

    PubMed

    Sobti, Ranbir Chander; Kumari, Mamtesh; Sharma, Vijay Lakshmi; Sodhi, Monika; Mukesh, Manishi; Shouche, Yogesh

    2009-11-01

    The present study was aimed to get the nucleotide sequences of a part of COII mitochondrial gene amplified from individuals of five species of Termites (Isoptera: Termitidae: Macrotermitinae). Four of them belonged to the genus Odontotermes (O. obesus, O. horni, O. bhagwatii and Odontotermes sp.) and one to Microtermes (M. obesi). Partial COII gene fragments were amplified by using specific primers. The sequences so obtained were characterized to calculate the frequencies of each nucleotide bases and a high A + T content was observed. The interspecific pairwise sequence divergence in Odontotermes species ranged from 6.5% to 17.1% across COII fragment. M. obesi sequence diversity ranged from 2.5 with Odontotermes sp. to 19.0% with O. bhagwatii. Phylogenetic trees drawn on the basis of distance neighbour-joining method revealed three main clades clustering all the individuals according to their genera and families.

  8. Crystal structure of bis­(N,N,N′,N′-tetra­methyl­guanidinium) tetra­chlorido­cuprate(II)

    PubMed Central

    Ndiaye, Mamadou; Samb, Abdoulaye; Diop, Libasse; Maris, Thierry

    2016-01-01

    In the structure of the title salt, (C5H14N3)2[CuCl4], the CuII atom in the anion lies on a twofold rotation axis. The tetra­chlorido­cuprate(II) anion adopts a flattened tetra­hedral coordination environment and inter­acts electrostatically with the tetra­methyl­guanidinium cation. The crystal packing is additionally consolidated through N—H⋯Cl and C—H⋯Cl hydrogen bonds, resulting in a three-dimensional network structure. PMID:27555960

  9. Complete mitochondrial genome of the penguin tetra, Thayeria boehlkei.

    PubMed

    Xiao, Gui-Bao; Li, Jiong-Tang; Li, Xiao-Min; Wang, Xiu-Li; Sun, Xiao-Wen

    2016-09-01

    The penguin tetra (Thayeria boehlkei) is one of the most popular aquarium fish and belongs to the family of Characidae. The composition, phylogeny, and classification of this family are uncertain. Here, the complete mitogenome of T. boehlkei was reported to be 16,524 bp in length. It contains 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. Comparing the mitochondrial genome of T. boehlkei with its congener Astyanax mexicanus revealed high-sequence similarity. The mitochondrial genome of T. boehlkei will contribute to conservation studies and evolution analysis of Characidae family.

  10. Cutaneous Ossifying Fibroma in a Neon Tetra (Paracheirodon innesi).

    PubMed

    Murphy, B; Imai, D M

    2016-01-01

    A cutaneous proliferative mass was identified arising from the caudal peduncle of a captive neon tetra fish (Paracheirodon innesi). The lesion was histologically consistent with an ossifying fibroma (OF), a fibro-osseous proliferative lesion typically identified in the jaws or tooth-associated supportive tissues of mammals. Although it has been previously reported, there is no recent report of this lesion occurring in a fish. This is the first report of a cutaneous ossifying fibroma in a characin fish. The authors speculate on the pathogenesis of this lesion, which may have arisen from the scale-associated mesenchymal tissues. PMID:27476108

  11. Cutaneous Ossifying Fibroma in a Neon Tetra (Paracheirodon innesi).

    PubMed

    Murphy, B; Imai, D M

    2016-01-01

    A cutaneous proliferative mass was identified arising from the caudal peduncle of a captive neon tetra fish (Paracheirodon innesi). The lesion was histologically consistent with an ossifying fibroma (OF), a fibro-osseous proliferative lesion typically identified in the jaws or tooth-associated supportive tissues of mammals. Although it has been previously reported, there is no recent report of this lesion occurring in a fish. This is the first report of a cutaneous ossifying fibroma in a characin fish. The authors speculate on the pathogenesis of this lesion, which may have arisen from the scale-associated mesenchymal tissues.

  12. Blade loss transient dynamics analysis. Volume 3: User's manual for TETRA program

    NASA Technical Reports Server (NTRS)

    Black, G. R.; Gallardo, V. C.; Storace, A. S.; Sagendorph, F.

    1981-01-01

    The users manual for TETRA contains program logic, flow charts, error messages, input sheets, modeling instructions, option descriptions, input variable descriptions, and demonstration problems. The process of obtaining a NASTRAN 17.5 generated modal input file for TETRA is also described with a worked sample.

  13. High-performance gel electrolytes with tetra-armed polymer network for Li ion batteries

    NASA Astrophysics Data System (ADS)

    Hazama, Taisuke; Fujii, Kenta; Sakai, Takamasa; Aoki, Masahiro; Mimura, Hideyuki; Eguchi, Hisao; Todorov, Yanko; Yoshimoto, Nobuko; Morita, Masayuki

    2015-07-01

    An organo gel with only 6 wt % tetra-armed poly(ethylene glycol), TetraPEG, was prepared and applied as a novel gel electrolyte for Li ion batteries (LIBs). The TetraPEG gel electrolyte containing 1.0 M LiPF6 in binary or ternary mixtures, i.e., EC + DEC and EC + DEC + TFEP (EC: ethylene carbonate, DEC: diethyl carbonate and TFEP: tris(2,2,2-trifluoroethyl)phosphate showed high ionic conductivity required for the use in LIB systems. The TetraPEG gel based on ternary EC + DEC + TFEP system acts as a nonflammable gel electrolyte at the TFEP content higher than 20 vol%. In cyclic voltammetry and charge/discharge cycling tests, the TetraPEG gel electrolytes showed good reversibility for a graphite negative electrode.

  14. Nano-accuracy measurements and the surface profiler by use of Monolithic Hollow Penta-Prism for precision mirror testing

    NASA Astrophysics Data System (ADS)

    Qian, Shinan; Wayne, Lewis; Idir, Mourad

    2014-09-01

    We developed a Monolithic Hollow Penta-Prism Long Trace Profiler-NOM (MHPP-LTP-NOM) to attain nano-accuracy in testing plane- and near-plane-mirrors. A new developed Monolithic Hollow Penta-Prism (MHPP) combined with the advantages of PPLTP and autocollimator ELCOMAT of the Nano-Optic-Measuring Machine (NOM) is used to enhance the accuracy and stability of our measurements. Our precise system-alignment method by using a newly developed CCD position-monitor system (PMS) assured significant thermal stability and, along with our optimized noise-reduction analytic method, ensured nano-accuracy measurements. Herein we report our tests results; all errors are about 60 nrad rms or less in tests of plane- and near-plane- mirrors.

  15. Tetra-Phocomelia: The Seal Limb Deformity - A Case Report

    PubMed Central

    Rathod, Setu; Ghose, Seetesh

    2015-01-01

    We report a case of term live baby with tetra-phocomelia born to a 35-year-old G3P2L2A0 with history of consanguineous marriage. She was an unbooked case from a tribal community with no previous antenatal visits. At 39 wk of gestation, she was admitted to our hospital with complaint of pain abdomen and on examination was found to be in second stage of labour. She delivered vaginally a term live 2.5 kg female baby with multiple anomalies. There was no history of drug intake, radiation exposure, maternal diabetes or family history of congenital anomalies to support the occurrence of tetra-phocomelia in this baby. The neonate also had multiple facial abnormalities like hypertelorism, microretrognathia and partial cleft palate. Further investigations revealed no abnormalities of internal organs. At present the baby is being followed up at our paediatric department. The case is reported owing to its rarity and term live birth. PMID:25859493

  16. Artificial neural networks for simultaneous spectrophotometric differential kinetic determination of Co(II) and V(IV).

    PubMed

    Safavi, A; Abdollahi, H; Hormozi Nezhad, M R

    2003-03-01

    A method for simultaneous analysis of V(IV) and Co(II) has been developed by using artificial neural network (ANN). This method is based on the difference of the chemical reaction rate of V(IV) and Co(II) with Fe(III) in the presence of chromogenic reagent, 1,10-phenanthroline. The reduced product of the reaction, Fe(II), can form a colored complex with 1,10-phenanthroline and make a visible spectrophotometric signal for indirect monitoring of the V(IV) and Co(II) concentrations. Feed forward neural networks have been trained to quantify considered metal ions in mixtures under optimum conditions. The networks were shown to be capable of correlating reduced spectral kinetic data using principal component analysis (PCA) of mixtures with individual metal ion. In this way an ANN containing three layers of nodes was trained. Sigmoidal and linear transfer functions were used in the hidden and output layers, respectively, to facilitate nonlinear calibration. Both V(IV) and Co(II) were analyzed in the concentration range of 0.1-4.0 mug ml(-1). The proposed method was also applied satisfactorily to the determination of considered metal ions in several synthetic and water samples. PMID:18968936

  17. Effects of tetra-arsenic tetra-sulfide on BXSB lupus-prone mice: a pilot study.

    PubMed

    Zhao, Y; Wen, G; Qiao, Z; Xu, H; Sun, Q; Huang, H; Shan, S; Mu, Z; Zhang, J

    2013-04-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease of uncertain etiology that affects multiple tissues and organs. Arsenic trioxide (ATO) has been used in lupus-prone mice with a regulatory effect on immune abnormality. Tetra-arsenic tetra-sulfide (As4S4), a traditional Chinese medicine, is effective on acute promyelocytic leukemia with mild side effects than ATO. In this study, a pilot study was performed to investigate the effects and the mechanism of As4S4 on the lupus-prone BXSB mice. Improvement of monocytosis (p<0.05) in spleen and decreased serum interleukin-6 (IL-6) (p=0.0277) were observed with As4S4 treatment. As4S4-treated mice exhibited amelioration of skin, liver and renal disease with mild side effects. Histological analysis revealed that As4S4 suppressed immune complex deposition, mesangial proliferation and inflammatory cell infiltration in kidney and liver. Our study support that As4S4 selectively suppresses cutaneous lupus and nephritis in BXSB mice and might be a potential treatment for SLE.

  18. Uptake, p53 Pathway Activation, and Cytotoxic Responses for Co(II) and Ni(II) in Human Lung Cells: Implications for Carcinogenicity

    PubMed Central

    Luczak, Michal W.; Zhitkovich, Anatoly

    2013-01-01

    Cobalt(II) and nickel(II) ions display similar chemical properties and act as hypoxia mimics in cells. However, only soluble Co(II) but not soluble Ni(II) is carcinogenic by inhalation. To explore potential reasons for these differences, we examined responses of human lung cells to both metals. We found that Co(II) showed almost 8 times higher accumulation than Ni(II) in H460 cells but caused a less efficient activation of the transcriptional factor p53 as measured by its accumulation, Ser15 phosphorylation, and target gene expression. Unlike Ni(II), Co(II) was ineffective in downregulating the p53 inhibitor MDM4 (HDMX). Co(II)-treated cells continued DNA replication at internal doses that caused massive apoptosis by Ni(II). Apoptosis and the overall cell death by Co(II) were delayed and weaker than by Ni(II). Inhibition of caspases but not programmed necrosis pathways suppressed Co(II)-induced cell death. Knockdown of p53 produced 50%–60% decreases in activation of caspases 3/7 and expression of 2 most highly upregulated proapoptotic genes PUMA and NOXA by Co(II). Overall, p53-mediated apoptosis accounted for 55% cell death by Co(II), p53-independent apoptosis for 20%, and p53/caspase-independent mechanisms for 25%. Similar to H460, normal human lung fibroblasts and primary human bronchial epithelial cells had several times higher accumulation of Co(II) than Ni(II) and showed a delayed and weaker caspase activation by Co(II). Thus, carcinogenicity of soluble Co(II) could be related to high survival of metal-loaded cells, which permits accumulation of genetic and epigenetic abnormalities. High cytotoxicity of soluble Ni(II) causes early elimination of damaged cells and is expected to be cancer suppressive. PMID:24068677

  19. Highly branched penta-saccharide-bearing amphiphiles for membrane protein studies

    PubMed Central

    Ehsan, Muhammad; Du, Yang; Scull, Nicola J.; Tikhonova, Elena; Tarrasch, Jeffrey; Mortensen, Jonas S.; Loland, Claus J.; Skiniotis, Georgios; Guan, Lan; Byrne, Bernadette; Kobilka, Brian K.; Chae, Pil Seok

    2016-01-01

    Detergents are essential tools for membrane protein manipulation. Micelles formed by detergent molecules have the ability to encapsulate the hydrophobic domains of membrane proteins. The resulting protein-detergent complexes (PDCs) are compatible with the polar environments of aqueous media, making structural and functional analysis feasible. Although a number of novel agents have been developed to overcome the limitations of conventional detergents, most of them have traditional head groups such as glucoside or maltoside. In this study, we introduce a class of amphiphiles, the PSA’Es with a novel highly branched penta-saccharide hydrophilic group. The PSA’Es conferred markedly increased stability to a diverse range of membrane proteins compared to conventional detergents, indicating a positive role for the new hydrophilic group in maintaining the native protein integrity. In addition, PDCs formed by PSA’Es were smaller and more suitable for electron microscopic analysis than those formed by DDM, indicating that the new agents have significant potential for the structure-function studies of membrane proteins. PMID:26966956

  20. Biological and biomedical functions of Penta-O-galloyl-D-glucose and its derivatives.

    PubMed

    Cao, Yanyan; Himmeldirk, Klaus B; Qian, Yanrong; Ren, Yulin; Malki, Ahmed; Chen, Xiaozhuo

    2014-07-01

    Penta-O-galloyl-D-glucose (PGG) is a simple hydrolysable tannin in plants. PGG exists in two anomeric forms, α-PGG and β-PGG. While β-PGG can be found in a wide variety of plants, α-PGG is rather rare in nature. Numerous studies with β-PGG revealed a wide variety of biological activities, such as anti-microbial and anti-cancer functions. Until recently, studies with α-PGG were limited by the lack of its availability. Since the development of an efficient chemical synthesis of the compound, several investigations have revealed its anti-diabetic, anti-cancer, and anti-platelet-coagulation functions. Based on structure-activity-relationship (SAR) studies with α-PGG, a variety of α-PGG-related novel compounds were synthesized and some of them have been shown to possess promising therapeutic activities. In this review, the authors will survey and evaluate the biological functions of PGG with a focus on α-PGG and its derivatives.

  1. Simple technique for the fabrication of a penta prism with high accuracy right angle deviation.

    PubMed

    Chatterjee, Sanjib; Pavan Kumar, Y

    2007-09-10

    What we believe to be a new technique for the fabrication of a penta prism (PP) with high accuracy right angle deviation of the incident beam is presented. We derive simple formulas relating to the error in right angle deviation with the errors in 45 degrees (beta) and 90 degrees (delta) angles of a PP, and we determine error in right angle deviation from the angle ((error in right angle deviation)r) between the plane wavefronts reflected from the right angled surfaces (external Fresnel reflection on the entrance surface and internal Fresnel reflection on the exit surface) of a PP and the angular error (delta) between the same surfaces. The error in right angle deviation is determined from the measurement of (error in right angle deviation)r using an autocollimator and a Fizeau interferometer, and error in right angle deviation is corrected to a high order of accuracy during the final stage of polishing one of the slanted surfaces of the PP. A new technique to determine the magnitude and direction of the small values of (error in right angle deviation)r is proposed and verified. The result for a PP is presented.

  2. Penta-prism long trace profiler (PPLTP) for measurement of grazing incidence space optics

    SciTech Connect

    Qian, S.; Li, H.; Takacs, P.Z.

    1996-05-01

    The Long Trace Profiler (LTP) is in use at a number of locations throughout the world for the measurement of the figure and mid- frequency roughness of x-ray mirrors. The standard configuration requires that the surface tested lie in a horizontal plane as the optical head is scanned along a horizontal line. For applications where gravity-induced sag of the surface cannot be tolerated, such as in x-ray telescope mirror metrology, it is desirable to measure the mirror as it is mounted in a vertical configuration. By making simple modifications to the standard LTP system, we have demonstrated that it is possible to use the LTP principle to measure the surface of x- ray mirrors and mandrels mounted in the vertical orientation. The major change in the LTP system is the use of a penta prism on a vertical translation stage to direct the probe beam onto the surface and the addition of a precision rotation stage to hold the test object. A 3-D map of the surface topography of the complete cylindrical asphere can be generated quite easily with this technique. Measurements with a prototype system indicate a slope error accuracy of better than 1 microradian is possible, with a figure error repeatability of better than 50 nm. 19 refs., 4 figs.

  3. Design of Compact Penta-Band and Hexa-Band Microstrip Antennas

    NASA Astrophysics Data System (ADS)

    Srivastava, Kunal; Kumar, Ashwani; Kanaujia, Binod K.

    2016-03-01

    This paper presents the design of two multi-band microstrip antennas. The antenna-1 gives Penta-Band and antenna-2 gives Hexa-band in the WLAN band. The frequency bands of the antenna-1 are Bluetooth 2.47 GHz (2.43 GHz-2.54 GHz), WiMax band 3.73 GHz (3.71 GHz-3.77 GHz), WLAN 5.1 GHz (4.99 GHz-5.13 GHz), upper WLAN 6.36 GHz (6.29 GHz-6.43 GHz), C band band 7.42 GHz (7.32 GHz-7.50 GHz) and the antenna-2 are WLAN band 2.6 GHz (2.56 GHz-2.63 GHz), 3.0 GHz (2.94 GHz-3.05 GHz), WiMax band 3.4 GHz (3.34 GHz-3.55 GHz), 4.85 GHz (4.81 GHz-4.92 GHz), WLAN 5.3 GHz (5.27 GHz-5.34 GHz) and upper WLAN 6.88 GHz. Both the antennas are fabricated and their measured results are presented to validate the simulated results. Proposed antennas have compact sizes and good radiation performances.

  4. Band gap engineering in penta-graphene by substitutional doping: first-principles calculations

    NASA Astrophysics Data System (ADS)

    Berdiyorov, G. R.; Dixit, G.; Madjet, M. E.

    2016-11-01

    Using density functional theory, we study the structure, electronic properties and partial charges of a new carbon allotrope—penta-graphene (PG)—substitutionally doped by Si, B and N. We found that the electronic bandgap of PG can be tuned down to 0.2 eV due to carbon substitutions. However, the value of the band gap depends on the type and location of the dopants. For example, the strongest reduction of the band gap is obtained for Si substitutions on the top (bottom) plane of PG, whereas the substitution in the middle plane of PG has a smaller effect on the band gap of the material. Surface termination with fluorine and hydroxyl groups results in an increase of the band gap together with considerable changes in electronic and atomic partial charge distribution in the system. Our findings, which are robust against the use of different exchange-correlation functionals, indicate the possibility of tuning the bandgap of the material to make it suitable for optoelectronic and photovoltaic applications.

  5. A comparative density functional study on electrical properties of layered penta-graphene

    SciTech Connect

    Yu, Zhi Gen Zhang, Yong-Wei

    2015-10-28

    We present a comparative study of the influence of the number of layers, the biaxial strain in the range of −3% to 3%, and the stacking misalignments on the electronic properties of a new 2D carbon allotrope, penta-graphene (PG), based on hybrid-functional method within the density functional theory (DFT). In comparison with local exchange-correlation approximation in the DFT, the hybrid-functional provides an accurate description on the degree of p{sub z} orbitals localization and bandgap. Importantly, the predicted bandgap of few-layer PG has a weak layer dependence. The bandgap of monolayer PG is 3.27 eV, approximately equal to those of GaN and ZnO; and the bandgap of few-layer PG decreases slowly with the number of layers (N) and converge to 2.57 eV when N ≥ 4. Our calculations using HSE06 functional on few-layer PG reveal that bandgap engineering by stacking misalignment can further tune the bandgap down to 1.37 eV. Importantly, there is no direct-to-indirect bandgap transition in PG by varying strain, layer number, and stacking misalignment. Owing to its tunable, robustly direct, and wide bandgap characteristics, few-layer PG is promising for optoelectronic and photovoltaic applications.

  6. Structures, functions and molecular evolution of the penta-EF-hand Ca2+-binding proteins.

    PubMed

    Maki, Masatoshi; Kitaura, Yasuyuki; Satoh, Hirokazu; Ohkouchi, Susumu; Shibata, Hideki

    2002-11-01

    Penta-EF-hand (PEF) proteins comprise a family of Ca(2+)-binding proteins that have five repetitive EF-hand motifs. Among the eight alpha-helices (alpha1-alpha8), alpha4 and alpha7 link EF2-EF3 and EF4-EF5, respectively. In addition to the structural similarities in the EF-hand regions, the PEF protein family members have common features: (i) dimerization through unpaired C-terminal EF5s, (ii) possession of hydrophobic Gly/Pro-rich N-terminal domains, and (iii) Ca(2+)-dependent translocation to membranes. Based on comparison of amino acid sequences, mammalian PEF proteins are classified into two groups: Group I PEF proteins (ALG-2 and peflin) and Group II PEF proteins (Ca(2+)-dependent protease calpain subfamily members, sorcin and grancalcin). The Group I genes have also been found in lower animals, plants, fungi and protists. Recent findings of specific interacting proteins have started to gradually unveil the functions of the noncatalytic mammalian PEF proteins.

  7. Band gap engineering in penta-graphene by substitutional doping: first-principles calculations.

    PubMed

    Berdiyorov, G R; Dixit, G; Madjet, M E

    2016-11-30

    Using density functional theory, we study the structure, electronic properties and partial charges of a new carbon allotrope-penta-graphene (PG)-substitutionally doped by Si, B and N. We found that the electronic bandgap of PG can be tuned down to 0.2 eV due to carbon substitutions. However, the value of the band gap depends on the type and location of the dopants. For example, the strongest reduction of the band gap is obtained for Si substitutions on the top (bottom) plane of PG, whereas the substitution in the middle plane of PG has a smaller effect on the band gap of the material. Surface termination with fluorine and hydroxyl groups results in an increase of the band gap together with considerable changes in electronic and atomic partial charge distribution in the system. Our findings, which are robust against the use of different exchange-correlation functionals, indicate the possibility of tuning the bandgap of the material to make it suitable for optoelectronic and photovoltaic applications. PMID:27633017

  8. Volvo Penta 4.3 GL E15 Emissions and Durability Test

    SciTech Connect

    Zoubul, G.; Cahoon, M.; Kolb, R.

    2011-10-01

    A new Volvo Penta carbureted 4.3 GL engine underwent emissions and dynamometer durability testing from break-in to expected end of life using an accelerated ICOMIA marine emissions cycle and E15 fuel. Only ethanol content was controlled. All aging used splash-blended E15 fuel. Exhaust emissions, exhaust gas temperature, torque, power, barometric pressure, air temperature, and fuel flow were measured at five intervals using site-blended E15 aging fuel and certification fuel (E0). The durability test cycle showed no noticeable impact on mechanical durability or engine power. Emissions performance degraded beyond the certification limit for this engine family, mostly occurring by 28% of expected life. Such degradation is inconsistent with prior experience. Comparisons showed that E15 resulted in lower CO and HC, but increased NOX, as expected for non-feedback-controlled carbureted engines with increased oxygen in the fuel. Fuel consumption also increased with E15 compared with E0. Throughout testing, poor starting characteristics were exhibited on E15 fuel for hot re-start and cold-start. Cranking time to start and smooth idle was roughly doubled compared with typical E0 operation. The carburetor was factory-set for lean operation to ensure emissions compliance. Test protocols did not include carburetor adjustment to account for increased oxygen in the E15 fuel.

  9. A comparative density functional study on electrical properties of layered penta-graphene

    NASA Astrophysics Data System (ADS)

    Yu, Zhi Gen; Zhang, Yong-Wei

    2015-10-01

    We present a comparative study of the influence of the number of layers, the biaxial strain in the range of -3% to 3%, and the stacking misalignments on the electronic properties of a new 2D carbon allotrope, penta-graphene (PG), based on hybrid-functional method within the density functional theory (DFT). In comparison with local exchange-correlation approximation in the DFT, the hybrid-functional provides an accurate description on the degree of pz orbitals localization and bandgap. Importantly, the predicted bandgap of few-layer PG has a weak layer dependence. The bandgap of monolayer PG is 3.27 eV, approximately equal to those of GaN and ZnO; and the bandgap of few-layer PG decreases slowly with the number of layers (N) and converge to 2.57 eV when N ≥ 4. Our calculations using HSE06 functional on few-layer PG reveal that bandgap engineering by stacking misalignment can further tune the bandgap down to 1.37 eV. Importantly, there is no direct-to-indirect bandgap transition in PG by varying strain, layer number, and stacking misalignment. Owing to its tunable, robustly direct, and wide bandgap characteristics, few-layer PG is promising for optoelectronic and photovoltaic applications.

  10. Band gap engineering in penta-graphene by substitutional doping: first-principles calculations.

    PubMed

    Berdiyorov, G R; Dixit, G; Madjet, M E

    2016-11-30

    Using density functional theory, we study the structure, electronic properties and partial charges of a new carbon allotrope-penta-graphene (PG)-substitutionally doped by Si, B and N. We found that the electronic bandgap of PG can be tuned down to 0.2 eV due to carbon substitutions. However, the value of the band gap depends on the type and location of the dopants. For example, the strongest reduction of the band gap is obtained for Si substitutions on the top (bottom) plane of PG, whereas the substitution in the middle plane of PG has a smaller effect on the band gap of the material. Surface termination with fluorine and hydroxyl groups results in an increase of the band gap together with considerable changes in electronic and atomic partial charge distribution in the system. Our findings, which are robust against the use of different exchange-correlation functionals, indicate the possibility of tuning the bandgap of the material to make it suitable for optoelectronic and photovoltaic applications.

  11. Characterization of a robust co(II) fluorescent complex deposited intact on HOPG.

    PubMed

    Heras-Ojea, María José; Mañeru, Daniel Reta; Rosado, Lidia; Zuazo, Juan Rubio; Castro, German R; Tewary, Subrata; Rajaraman, Gopalan; Aromí, Guillem; Jiménez, Erika; Sañudo, E Carolina

    2014-08-11

    The new diimine fluorescent ligand ACRI-1 based on a central acridine yellow core is reported along with its coordination complex [Co2 (ACRI-1)2 ] (1), a fluorescent weak ferromagnet. Due to the strong fluorescence of the acridine yellow fluorophore, it is not completely quenched when the ligand is coordinated to Co(II) . The magnetic properties of bulk complex 1 and its stability in solution have been studied. Complex 1 has been deposited on highly ordered pyrolitic graphite (HOGP) from solution. The thin films prepared have been characterized by AFM, time-of-flight secondary ion mass spectrometry (TOF-SIMS), grazing incidence X-ray diffraction (GIXRD), X-ray absorption spectroscopy (XAS), X-ray magnetic circular dichroism (XMCD) and theoretical calculations. The data show that the complex is robust and remains intact on the surface of graphite.

  12. Two Isostructural Coordination Polymers Showing Diverse Magnetic Behaviors: Weak Coupling (Ni(II)) and an Ordered Array of Single-Chain Magnets (Co(II)).

    PubMed

    Chen, Min; Zhao, Hui; Sañudo, E Carolina; Liu, Chun-Sen; Du, Miao

    2016-04-18

    Two isomorphic 3-D complexes with the formulas [M3(TPTA) (OH)2(H2O)4]n (M = Ni for 1 and Co for 2; H4TPTA = [1,1':4',1″-terphenyl]-2',3,3″,5'-tetracarboxylic acid) have been synthesized and magnetically characterized. Complexes 1 (Ni(II)) and 2 (Co(II)) have the same 1-D rod-shaped inorganic SBUs but exhibit significantly different magnetic properties. Complex 2(Co(II)) is a 3-D arrangement of a 1-D Co(II) single-chain magnet (SCM), while complex 1(Ni(II)) exhibits weak coupling. PMID:27022765

  13. Two Isostructural Coordination Polymers Showing Diverse Magnetic Behaviors: Weak Coupling (Ni(II)) and an Ordered Array of Single-Chain Magnets (Co(II)).

    PubMed

    Chen, Min; Zhao, Hui; Sañudo, E Carolina; Liu, Chun-Sen; Du, Miao

    2016-04-18

    Two isomorphic 3-D complexes with the formulas [M3(TPTA) (OH)2(H2O)4]n (M = Ni for 1 and Co for 2; H4TPTA = [1,1':4',1″-terphenyl]-2',3,3″,5'-tetracarboxylic acid) have been synthesized and magnetically characterized. Complexes 1 (Ni(II)) and 2 (Co(II)) have the same 1-D rod-shaped inorganic SBUs but exhibit significantly different magnetic properties. Complex 2(Co(II)) is a 3-D arrangement of a 1-D Co(II) single-chain magnet (SCM), while complex 1(Ni(II)) exhibits weak coupling.

  14. Mechanism of the tunable structural color of neon tetra

    NASA Astrophysics Data System (ADS)

    Yoshioka, Shinya

    2010-03-01

    Many examples of the structural color can be found in butterfly wings, beetle's elytra and bird feathers. Since the color-producing microstructures of these examples mainly consist of stable materials, for example, dried cuticles in insects and keratin and melanin granules in bird feathers, it is impossible to actively change the microstructure. On the other hand, some fish have the tunability in their structural colors. For example, a small tropical fish, neon tetra, has a longitudinal stripe that looks blue-green in the day time, while it changes into deep violet at night. This fact clearly indicates the variability in the microstructure. It is known that the iridophore of the stripe part of neon tetra contains two stacks of thin light-reflecting platelets that are made of guanine crystal. Since the arrangement of the platelets is observed periodic, the stack is thought to cause the structural color through the multilayer thin-film interference. Consequently, the variability in the color is thought to originate from the variation in the distance between the platelets. Two explanations have been proposed so far for the distance variation. Lythoge and Shand considered that the distance is controlled by osmotic pressure that induces the inflow of the water into the iridophore[1]. On the other hand, Nagaishi et al. proposed a different model, called Venetian blind model, in which the inclination angle of the platelets is varied, resulting in the change in the distance[2]. Recently, we have performed detailed optical measurements on the iridophore of neon tetra. We have paid particular attention to the direction of the reflected light, since the Venetian blind model expects that the direction varies with the color change owing to the tilt of the platelets. We present the experimental results and quantitatively discuss the validity of the Venetian blind model. [4pt] [1] J. N. Lythgoe, and J. Shand, J Physiol. 325, 23-34 (1982). [0pt] [2] H. Nagaishi, N. Oshima, and R

  15. Two tetra-Cd(II)-substituted vanadogermanate frameworks.

    PubMed

    Zhou, Jian; Zhao, Jun-Wei; Wei, Qi; Zhang, Jie; Yang, Guo-Yu

    2014-04-01

    Two new tetra-Cd(II)-substituted vanadogermanate frameworks {(CdX)4Ge8V(IV)10O46(H2O)[V(III)(H2O)2]4(GeO2)4}·8H2O (X = ethylenediamine (en, 1) and 1,2-diaminopropane (dap, 2)) were hydrothermally prepared and characterized by IR spectra, elemental analysis, powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and X-ray single-crystal diffraction. Both are isomorphic, and their 3-D frameworks are made up of tetra-Cd(II)-substituted {(CdX)4Ge8V(IV)10O46(H2O)}(12-) fundamental building units interconnected through planar tetra-V(III) [V(III)4O2(H2O)8](8-) clusters and tetrahedral GeO4 bridges. In the unique {(CdX)4Ge8V(IV)10O46(H2O)}(12-) cage, four [Ge2O7] dimers and four CdO4N2 trigonal prisms are alternately concatenated by μ3-O bridges to create a round {Ge8Cd4O28(X)4}(16-) fragment, five VO5 groups are linked by sharing edges to generate a pentanuclear [V5O17] subunit, and then the {Ge8Cd4O28(X)4}(16-) fragment is sandwiched by two V5O17 subunits via sharing O-atoms producing a D4h-symmetric {(CdX)4Ge8V(IV)10O46(H2O)}(12-) cage with a free water molecule located at the center. As we know, both display unprecedented 3-D organic-inorganic hybrid frameworks built up from the largest number of transition-metal-substituted vanadogermanate {(CdX)4Ge8V(IV)10O46}(12-) cluster shells linked by both GeO4 tetrahedra and rare [V(III)4O2(H2O)8](8-) clusters. Magnetic measurements reveal the antiferromagnetic couplings within the magnetic vanadium centers. PMID:24641354

  16. Alcohol challenge and sensitivity to change of The Essential Tremor Rating Assessment Scale (TETRAS)

    PubMed Central

    Voller, Bernhard; Lines, Emily; McCrossin, Gayle; Artiles, Aaron; Tinaz, Sule; Lungu, Codrin; Hallett, Mark; Haubenberger, Dietrich

    2014-01-01

    Background The Essential Tremor (ET) Rating Assessment Scale (TETRAS) has shown excellent inter- and intra-rater reliability. To assess the scale’s ability to detect changes in tremor severity, we compared TETRAS performance with standard postural tremor accelerometry during a standardized ethanol challenge. Methods Fifteen adult ET patients received a single oral ethanol dose calculated to reach 0.05 g/dl breath alcohol content (brAC) on two different study days. Two investigators independently assessed the effects with accelerometry on one day and with TETRAS on another day. Measurements were taken at 8 time-points (2 time-points baseline and 6 time-points up to 2 hours post ethanol). Further outcome measures included brAC readings at the same time points. Results Because correlation between TETRAS and accelerometry revealed a logarithmic relation, for all comparisons, accelerometry data were log-transformed and a cumulative score logACC(R+L) was calculated. Correlation between logACC(R+L) and TETRAS was significant (r= 0.57, p<0.01). Repeated measures ANOVA for both TETRAS and accelerometry before and after ethanol showed a significant effect of time-point (F=34.6, p<0.01; F=13.5, p<0.01). Corrected post-hoc tests showed a difference between baseline and each of the following 6 time-points. TETRAS and brAC were significantly correlated (r=−0.29, p<0.01). Intra-rater test-retest analysis between baseline measures showed high correlation (ICC=0.974, p<0.001). The ethanol challenge showed excellent reproducibility. Conclusion We demonstrated sensitivity of the TETRAS performance scale to change after a therapeutic intervention. Our study provides responsiveness validity for TETRAS, further establishing its potential as a valid instrument for ET evaluation in both clinical and research settings. PMID:24123358

  17. (μ-3,4-Diacetyl­hexa-2,4-diene-2,5-diol­ato-κ4 O 2,O 3:O 4,O 5)bis­[aqua(1,10-phen­an­thro­line-κ2 N,N′)copper(II)] bis­(tetra­fluorid­oborate) monohydrate

    PubMed Central

    Tovilla, Jorge A.; Hernández-Ortega, Simón; Valdés-Martínez, Jesús

    2009-01-01

    In the title compound, [Cu2(C10H12O4)(C12H8N2)2(H2O)2](BF4)2·H2O, the two Cu atoms are each chelated by the acetyl­acetonate unit of the 3,4-diacetyl­hexa-2,4-diene-2,5-diolate (tae) ligand. The Cu atoms are square-pyramidally penta­coordinated, with one bidentate 1,10-phenanthroline (phen) and the tae ligand basal and one water mol­ecule apical. The pyridyl rings of the phen ligands participate in π–π [centroid–centroid distance = 3.894 (3) Å] and C—H ⋯ π inter­actions, generating layers which are inter­connected through O—H⋯O and O—H⋯F hydrogen bonds between the water mol­ecules and the tetra­fluorido­borate anions. The F atoms of both tetra­fluorido­borate anions are each disordered over two positions of equal occupancy. PMID:21582322

  18. Crystal structure of tetra­methyl­tetra­thia­fulvalenium (1S)-camphor-10-sulfonate dihydrate

    PubMed Central

    Sommer, Mathieu; Allain, Magali; Mézière, Cécile; Pop, Flavia; Giffard, Michel

    2015-01-01

    Electro-oxidation of tetra­methyl­tetra­thia­fulvalene (TMTTF) in the presence of the chiral anion (1S)-camphor-10-sulfonate (S-camphSO3 −) in tetra­hydro­furan/water medium afforded a 1/1 salt formulated as TMTTF·S-camphSO3·2H2O or 2-(4,5-dimethyl-1,3-di­thiol-2-yl­idene)-4,5-dimethyl-1,3-di­thiole radical ion (1+) [(1S)-7,7-dimethyl-2-oxobi­cyclo­[2.2.1]heptan-1-yl]methane­sulfonate dihydrate, C10H12S4 +·C10H15O4S−·2H2O. In this salt, two independent TMTTF units are present but, in both cases, the observed bond lengths and especially the central C=C distance [1.392 (6) and 1.378 (6) Å] are in agreement with a complete oxidation of TMTTF which is thus present as TMTTF. + radical cations. These cations form one-dimensional stacks in which they are associated two by two, forming dimers with short [3.472 (1) to 3.554 (2) Å] S⋯S contacts. The two S-camphSO3 anions present also form stacks and are connected with each other via the water mol­ecules with many O—H⋯O hydrogen bonds ranging from 1.86 (3) to 2.15 (4) Å; the O—H⋯O hydrogen-bonding network can be described as being constituted of C 2 2(6) chains bearing R 3 3(11) lateral rings. On the other hand, the columns of cations and anions are connected through C—H⋯O hydrogen bonds, forming a system expanding in three directions; finally, the result is a three-dimensional network of O—H⋯O and C—H⋯O hydrogen bonds. PMID:26279858

  19. Epigallocatechin-3-gallate and penta-O-galloyl-β-D-glucose inhibit protein phosphatase-1.

    PubMed

    Kiss, Andrea; Bécsi, Bálint; Kolozsvári, Bernadett; Komáromi, István; Kövér, Katalin E; Erdődi, Ferenc

    2013-01-01

    Protein phosphatase-1 (PP1) and protein phosphatase-2A (PP2A) are responsible for the dephosphorylation of the majority of phosphoserine/threonine residues in cells. In this study, we show that (-)-epigallocatechin-3-gallate (EGCG) and 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), polyphenolic constituents of green tea and tannins, inhibit the activity of the PP1 recombinant δ-isoform of the PP1 catalytic subunit and the native PP1 catalytic subunit (PP1c) with IC(50) values of 0.47-1.35 μm and 0.26-0.4 μm, respectively. EGCG and PGG inhibit PP2Ac less potently, with IC(50) values of 15 and 6.6 μm, respectively. The structure-inhibitory potency relationships of catechin derivatives suggests that the galloyl group may play a major role in phosphatase inhibition. The interaction of EGCG and PGG with PP1c was characterized by NMR and surface plasmon resonance-based binding techniques. Competitive binding assays and molecular modeling suggest that EGCG docks at the hydrophobic groove close to the catalytic center of PP1c, partially overlapping with the binding surface of microcystin-LR or okadaic acid. This hydrophobic interaction is further stabilized by hydrogen bonding via hydroxyl/oxo groups of EGCG to PP1c residues. Comparative docking shows that EGCG binds to PP2Ac in a similar manner, but in a distinct pose. Long-term treatment (24 h) with these compounds and other catechins suppresses the viability of HeLa cells with a relative effectiveness reminiscent of their in vitro PP1c-inhibitory potencies. The above data imply that the phosphatase-inhibitory features of these polyphenols may be implicated in the wide spectrum of their physiological influence.

  20. Penta-EF-Hand Protein Peflin Is a Negative Regulator of ER-To-Golgi Transport

    PubMed Central

    Held, Aaron; Sargeant, John; Thorsen, Kevin; Hay, Jesse C.

    2016-01-01

    Luminal calcium regulates vesicle transport early in the secretory pathway. In ER-to-Golgi transport, depletion of luminal calcium leads to significantly reduced transport and a buildup of budding and newly budded COPII vesicles and vesicle proteins. Effects of luminal calcium on transport may be mediated by cytoplasmic calcium sensors near ER exits sites (ERES). The penta-EF-hand (PEF) protein apoptosis-linked gene 2 (ALG-2) stabilizes sec31A at ER exit sites (ERES) and promotes the assembly of inner and outer shell COPII components. However, in vitro and intact cell approaches have not determined whether ALG-2 is a negative or positive regulator, or a regulator at all, under basal physiological conditions. ALG-2 interacts with another PEF protein, peflin, to form cytosolic heterodimers that dissociate in response to calcium. However, a biological function for peflin has not been demonstrated and whether peflin and the ALG-2/peflin interaction modulates transport has not been investigated. Using an intact, single cell, morphological assay for ER-to-Golgi transport in normal rat kidney (NRK) cells, we found that depletion of peflin using siRNA resulted in significantly faster transport of the membrane cargo VSV-G. Double depletion of peflin and ALG-2 blocked the increased transport resulting from peflin depletion, demonstrating a role for ALG-2 in the increased transport. Furthermore, peflin depletion caused increased targeting of ALG-2 to ERES and increased ALG-2/sec31A interactions, suggesting that peflin may normally inhibit transport by preventing ALG-2/sec31A interactions. This work identifies for the first time a clear steady state role for a PEF protein in ER-to-Golgi transport—peflin is a negative regulator of transport. PMID:27276012

  1. Identification and characterization of two penta-EF-hand Ca(2+)-binding proteins in Dictyostelium discoideum.

    PubMed

    Ohkouchi, S; Nishio, K; Maeda, M; Hitomi, K; Adachi, H; Maki, M

    2001-08-01

    Penta-EF-hand (PEF) proteins such as ALG-2 (apoptosis-linked gene 2 product) and the calpain small subunit are a newly classified family of Ca(2+)-binding proteins that possess five EF-hand-like motifs. We identified two mutually homologous PEF proteins, designated DdPEF-1 and DdPEF-2 (64% amino acid residue identities), in the cellular slime mold Dictyostelium discoideum. Both PEF proteins showed a higher similarity to mammalian ALG-2 and peflin (Group I PEF proteins) than to calpain and sorcin subfamily (Group II PEF proteins) in the first EF-hand (EF-1) regions. Northern blot analyses revealed that DdPEF-1 and DdPEF-2 were constitutively expressed throughout development of Dictyostelium, but their levels of expression were developmentally regulated. In situ hybridization analyses demonstrated that DdPEF-1 was expressed in both the anterior prestalk and the posterior prespore regions of the tipped aggregate, slugs and early culminants. On the other hand, DdPEF-2 was dominantly expressed in the anterior tip region of these multicellular structures. Both PEF proteins were detected as 22-23-kDa proteins in soluble fractions in the presence of EGTA but in particulate fractions in the presence of Ca(2+) by Western blotting using specific monoclonal antibodies. Together with the finding of PEF-like sequences in DNA databases of plants, fungi and protists, our results strongly suggest that Group I PEF proteins are ubiquitously present in all eukaryotes and play important roles in basic cellular functions.

  2. Crystal structure of the tetra­gonal polymorph of bis­(1-ethyl-3-methyl­imidazolium) tetra­bromido­cadmate

    PubMed Central

    Đorđević, Tamara; Gerger, Sabrina; Karanović, Ljiljana

    2016-01-01

    Both unique Cd atoms in the tetra­gonal polymorph of bis­(1-ethyl-3-methyl­imidazolium) tetra­bromido­cadmate, (C6H11N2)2[CdBr4], occupy special positions (site symmetry -4). The crystal structure consists of isolated tetra­hedral [CdBr4]2− anions which are surrounded by 1-ethyl-3-methyl­imidazolium cations. The methyl and ethyl side chains of the cations show positional disorder in a 0.590 (11):0.410 (11) ratio. In the crystal, (C6H11N2)+ cations display three weak C—H⋯Br hydrogen-bond inter­actions through the imidazolium ring H atoms with the Br− ligands of the surrounding complex anions. The alkyl groups of the side chains are not involved in hydrogen bonding. PMID:27555953

  3. Spectroscopic and mycological studies of Co(II), Ni(II) and Cu(II) complexes with 4-aminoantipyrine derivative

    NASA Astrophysics Data System (ADS)

    Sharma, Amit Kumar; Chandra, Sulekh

    2011-10-01

    Complexes of the type [M(L)X 2], where M = Co(II), Ni(II) and Cu(II), have been synthesized with novel NO-donor Schiff's base ligand, 1,4-diformylpiperazine bis(4-imino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one) which is obtained by the acid catalyzed condensation of 1,4-diformylpiperazine with 4-aminoantipyrine. The elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV, NMR, mass and EPR studies of the compounds led to the conclusion that the ligand acts as tetradentate chelate. The Schiff's base ligand forms hexacoordinated complexes having octahedral geometry for Ni(II) and tetragonal geometry for Co(II) and Cu(II) complexes. The mycological studies of the compounds were examined against the several opportunistic pathogens, i.e., Alternaria brassicae, Aspergillus niger and Fusarium oxysporum. The Cu(II) complexes were found to have most fungicidal behavior.

  4. Ni(II) And Co(II) Sensing By Escherichia Coli RcnR

    SciTech Connect

    Iwig, J.S.; Leitch, S.; Herbst, R.W.; Maroney, M.J.; Chivers, P.T.

    2009-05-18

    Escherichia coli RcnR and Mycobacterium tuberculosis CsoR are the founding members of a recently identified, large family of bacterial metal-responsive DNA-binding proteins. RcnR controls the expression of the metal efflux protein RcnA only in response to Ni(II) and Co(II) ions. Here, the interaction of Ni(II) and Co(II) with wild-type and mutant RcnR proteins is examined to understand how these metals function as allosteric effectors. Both metals bind to RcnR with nanomolar affinity and stabilize the protein to denaturation. X-ray absorption and electron paramagnetic resonance spectroscopies reveal six-coordinate high-spin sites for each metal that contains a thiolate ligand. Experimental data support a tripartite N-terminal coordination motif (NH{sub 2}-Xaa-NH-His) that is common for both metals. However, the Ni(II)- and Co(II)-RcnR complexes are shown to differ in the remaining coordination environment. Each metal coordinates a conserved Cys ligand but with distinct M-S distances. Co(II)-thiolate coordination has not been observed previously in Ni(II)-/Co(II)-responsive metalloregulators. The ability of RcnR to recruit ligands from the N-terminal region of the protein distinguishes it from CsoR, which uses a lower coordination geometry to bind Cu(I). These studies facilitate comparisons between Ni(II)-RcnR and NikR, the other Ni(II)-responsive transcriptional regulator in E. coli, to provide a better understanding how different nickel levels are sensed in E. coli. The characterization of the Ni(II)- and Co(II)-binding sites in RcnR, in combination with bioinformatics analysis of all RcnR/CsoR family members, identified a four amino acid fingerprint that likely defines ligand-binding specificity, leading to an emerging picture of the similarities and differences between different classes of RcnR/CsoR proteins.

  5. Redetermination of tantalum penta­bromide, (TaBr5)2

    PubMed Central

    Habermehl, Katja; Pantenburg, Ingo; Meyer, Gerd

    2010-01-01

    Crystals of di-μ-bromido-bis­[tetra­bromidotantalum(V)], (TaBr5)2, were obtained by recrystallization at 773 K. A first crystal structure study of (TaBr5)2 was reported by Rolsten [J. Am. Chem. Soc. (1958) ▶, 80, 2952–2953], who analysed the powder diffraction pattern and came to the conclusion that it crystallizes isotypically with (NbBr5)2 in a primitive ortho­rhom­bic cell. These findings are not in agreement with our current results of a monoclinic C-centred structure. (TaBr5)2 is isotypic with α-(NbCl5)2. The crystal structure contains [TaBr6] octa­hedra sharing common edges forming [TaBr5]2 dimers. Two crystallographically independent dimers with symmetries m and 2/m and Ta⋯Ta distances of 4.1574 (11) and 4.1551 (15) Å, respectively, are present in the structure. PMID:21588474

  6. Binuclear Cu(II) and Co(II) Complexes of Tridentate Heterocyclic Shiff Base Derived from Salicylaldehyde with 4-Aminoantipyrine

    PubMed Central

    Al-Obaidi, Omar Hamad Shihab

    2012-01-01

    New binuclear Co(II) and Co(II) complexes of ONO tridentate heterocyclic Schiff base derived from 4-aminoantipyrine with salicylaldehyde have been synthesized and characterized on the bases of elemental analysis, UV-Vis., FT-IR, and also by aid of molar conductivity measurements, magnetic measurements, and melting points. It has been found that the Schiff bases with Cu(II) or Co(II) ion forming binuclear complexes on (1 : 1) “metal : ligand” stoichiometry. The molar conductance measurements of the complexes in DMSO correspond to be nonelectrolytic nature for all prepared complexes. Distorted octahedral environment is suggested for metal complexes. A theoretical treatment of the formation of complexes in the gas phase was studied, and this was done by using the HyperChem-6 program for the molecular mechanics and semi-empirical calculations. The free ligand and its complexes have been tested for their antibacterial activities against two types of human pathogenic bacteria: the first type (Staphylococcus aureus) is Gram positive and the second type (Escherichia coli) is Gram negative (by using agar well diffusion method). Finally, it was found that compounds show different activity of inhibition on growth of the bacteria. PMID:22611346

  7. Cranial skeletogenesis and osteology of the redeye tetra Moenkhausia sanctaefilomenae.

    PubMed

    Walter, B E

    2013-01-01

    The skeletogenesis and osteology of the syncranium of the redeye tetra Moenkhausia sanctaefilomenae is described. Skeletal development is rapid, with many elements of the chondrocranium and splanchnocranium well formed prior to the onset of ossification. The chondrocranium develops from an initial set of cartilaginous precursors, and continued elaboration proceeds from a series of processes which expand and converge to form the floor of the cranial vault, the otic capsule, the supraorbital bridge and the ethmoid region. Prodigious growth is observed for a number of splanchnocranial elements, including the Meckel's cartilage and the ceratohyal cartilage. Ossification occurs in overlapping phases with initial ossification of the jaws and neurocranial floor followed by the splanchnocranium, the supraorbital bridges and the ethmoid and cranial vault. Teeth are observed primarily on the premaxilla and dentary, while a single tooth is present on the maxilla. Particular cartilages, which had originally formed in the early larva, appear to degenerate and have no ossified representative in the adult syncranium. The cranial development for M. sanctaefilomenae is compared to those of other characiforms. PMID:23331139

  8. Penta- and hexa-coordinate ferric hemoglobins display distinct pH titration profiles measured by Soret peak shifts.

    PubMed

    Uppal, Sheetal; Kumar, Amit; Shandilya, Manish; Mukhi, Nitika; Singh, Amit Kumar; Kateriya, Suneel; Kaur, Jagreet; Kundu, Suman

    2016-10-01

    Hemoglobins with diverse characteristics have been identified in all kingdoms of life. Their ubiquitous presence indicates that these proteins play important roles in physiology, though function for all hemoglobins are not yet established with certainty. Their physiological role may depend on their ability to bind ligands, which in turn is dictated by their heme chemistry. However, we have an incomplete understanding of the mechanism of ligand binding for these newly discovered hemoglobins and the measurement of their kinetic parameters depend on their coordination at the heme iron. To gain insights into their functional role, it is important to categorize the new hemoglobins into either penta- or hexa-coordinated varieties. We demonstrate that simple pH titration and absorbance measurements can determine the coordination state of heme iron atom in ferric hemoglobins, thus providing unambiguous information about the classification of new globins. This method is rapid, sensitive and requires low concentration of protein. Penta- and hexa-coordinate hemoglobins displayed distinct pH titration profiles as observed in a variety of hemoglobins. The pentacoordinate distal histidine mutant proteins of hexacoordinate hemoglobins and ligand-bound hexacoordinate forms of pentacoordinate hemoglobins reverse the pH titration profiles, thus validating the sensitivity of this spectroscopic technique.

  9. Paediatric trauma and trauma care in Flanders (Belgium). Methodology and first descriptive results of the PENTA registry.

    PubMed

    Van de Voorde, Patrick; Sabbe, Marc; Calle, Paul; Lesaffre, Emmanuel; Rizopoulos, Dimitris; Tsonaka, Roula; Christiaens, Daphne; Vantomme, Anneleen; De Jaeger, Annick; Matthys, Dirk

    2008-11-01

    Paediatric injury surveillance and prevention are definite priorities for the European, Belgian, and Flemish authorities. Current available data for Flanders (Belgium) are fragmentary and out-of-date. The PENTA registry (PaEdiatric Network around TraumA) was therefore set up to obtain recent population-based data on trauma and trauma care in children and youngsters in Flanders. Data were collected prospectively in a representative sample (n = 18) of Flemish emergency departments (ED). All children (age 0-17 years) who presented at the ED in 2005 or died prehospital due to trauma were included. The registry was split into two levels. The basic A registry ('all' trauma) consisted of 30 variables, and the more exhaustive B registry ('severe trauma', defined as length of hospitalisation >48 hours, including all nonsurvivors) collected data on 291 variables. The incidence for paediatric trauma presenting at Flemish ED was approximately 119/1000/year. Further data were collected in a random sample of 7,879 cases (21.9% of 35,900 eligible patients). Of all cases, 0.8% were considered 'severe' and included in the B registry. In conclusion, the 'burden' of injury in Flanders is still enormous. PENTA provides the first population-based data about the circumstances and the extent of injury in children and youngsters for the Flemish region. In this article we present in detail the surplus value of the methods used, the difficulties encountered, and the most relevant epidemiological findings from the registry. PMID:18202851

  10. Penta- and hexa-coordinate ferric hemoglobins display distinct pH titration profiles measured by Soret peak shifts.

    PubMed

    Uppal, Sheetal; Kumar, Amit; Shandilya, Manish; Mukhi, Nitika; Singh, Amit Kumar; Kateriya, Suneel; Kaur, Jagreet; Kundu, Suman

    2016-10-01

    Hemoglobins with diverse characteristics have been identified in all kingdoms of life. Their ubiquitous presence indicates that these proteins play important roles in physiology, though function for all hemoglobins are not yet established with certainty. Their physiological role may depend on their ability to bind ligands, which in turn is dictated by their heme chemistry. However, we have an incomplete understanding of the mechanism of ligand binding for these newly discovered hemoglobins and the measurement of their kinetic parameters depend on their coordination at the heme iron. To gain insights into their functional role, it is important to categorize the new hemoglobins into either penta- or hexa-coordinated varieties. We demonstrate that simple pH titration and absorbance measurements can determine the coordination state of heme iron atom in ferric hemoglobins, thus providing unambiguous information about the classification of new globins. This method is rapid, sensitive and requires low concentration of protein. Penta- and hexa-coordinate hemoglobins displayed distinct pH titration profiles as observed in a variety of hemoglobins. The pentacoordinate distal histidine mutant proteins of hexacoordinate hemoglobins and ligand-bound hexacoordinate forms of pentacoordinate hemoglobins reverse the pH titration profiles, thus validating the sensitivity of this spectroscopic technique. PMID:27449132

  11. Penta-Twinned Copper Nanorods: Facile Synthesis via Seed-Mediated Growth and Their Tunable Plasmonic Properties

    DOE PAGESBeta

    Luo, Ming; Ruditskiy, Aleksey; Peng, Hsin-Chieh; Tao, Jing; Figueroa-Cosme, Legna; He, Zhike; Xia, Younan

    2016-01-07

    When seed-mediated growth is used as a versatile approach to the synthesis of penta-twinned Cu nanorods with uniform diameters and controllable aspect ratios is reported. The success of this approach relies on our recent synthesis of uniform Pd decahedra, with sizes in the range of 6–20 nm. The Pd decahedral seeds can direct the heterogeneous nucleation and growth of Cu along the fivefold axis to produce nanorods with uniform diameters defined by the lateral dimension of the original seeds. Due to a large mismatch in the lattice constants between Cu and Pd (7.1%), the deposited Cu is forced to growmore » along one side of the Pd decahedral seed, generating a nanorod with an asymmetric distribution of Cu, with the Pd seed situated at one of the two ends. According to extinction spectra, the as-obtained Cu nanorods can be stored in water under the ambient conditions for at least six months without noticeable degradation. The resulting stability allows us to systematically investigate the size-dependent surface plasmon resonance properties of the penta-twinned Cu nanorods. With the nanorod transverse modes positioned at 560 nm, the longitudinal modes can be readily tuned from the visible to the near-infrared region by controlling the aspect ratio.« less

  12. Magnetic properties of weakly exchange-coupled high spin Co(II) ions in pseudooctahedral coordination evaluated by single crystal X-band EPR spectroscopy and magnetic measurements.

    PubMed

    Neuman, Nicolás I; Winkler, Elín; Peña, Octavio; Passeggi, Mario C G; Rizzi, Alberto C; Brondino, Carlos D

    2014-03-01

    We report single-crystal X-band EPR and magnetic measurements of the coordination polymer catena-(trans-(μ2-fumarato)tetraaquacobalt(II)), 1, and the Co(II)-doped Zn(II) analogue, 2, in different Zn:Co ratios. 1 presents two magnetically inequivalent high spin S = 3/2 Co(II) ions per unit cell, named A and B, in a distorted octahedral environment coordinated to four water oxygen atoms and trans coordinated to two carboxylic oxygen atoms from the fumarate anions, in which the Co(II) ions are linked by hydrogen bonds and fumarate molecules. Magnetic susceptibility and magnetization measurements of 1 indicate weak antiferromagnetic exchange interactions between the S = 3/2 spins of the Co(II) ions in the crystal lattice. Oriented single crystal EPR experiments of 1 and 2 were used to evaluate the molecular g-tensor and the different exchange coupling constants between the Co(II) ions, assuming an effective spin S′= 1/2. Unexpectedly, the eigenvectors of the molecular g-tensor were not lying along any preferential bond direction, indicating that, in high spin Co(II) ions in roughly octahedral geometry with approximately axial EPR signals, the presence of molecular pseudo axes in the metal site does not determine preferential directions for the molecular g-tensor. The EPR experiment and magnetic measurements, together with a theoretical analysis relating the coupling constants obtained from both techniques, allowed us to evaluate selectively the exchange coupling constant associated with hydrogen bonds that connect magnetically inequivalent Co(II) ions (|JAB(1/2)| = 0.055(2) cm(–1)) and the exchange coupling constant associated with a fumarate bridge connecting equivalent Co(II) ions (|JAA(1/2)| ≈ 0.25 (1) cm(–1)), in good agreement with the average J(3/2) value determined from magnetic measurements.

  13. Synthesis, characterization and biomolecule-binding properties of novel tetra-platinum(II)-thiopyridylporphyrins.

    PubMed

    Lourenço, Leandro M O; Iglesias, Bernardo A; Pereira, Patrícia M R; Girão, Henrique; Fernandes, Rosa; Neves, Maria G P M S; Cavaleiro, José A S; Tomé, João P C

    2015-01-14

    The new complexes tetra-platinum(II)-thiopyridylporphyrin 3 and tetra-platinum(II)-thiopyridylporphyrinato Zn(II) 4 were obtained by coordination of the peripheral thiopyridyl units of the free-base 5,10,15,20-tetrakis[2,3,5,6-tetrafluoro-4-(4-pyridylsulfanyl)phenyl]porphyrin 1 or their corresponding zinc complex 2, respectively, with four chloro(2,2'-bipyridine)platinum(II) [Pt(bpy)Cl](+) units. Both compounds were characterized by several spectroscopic techniques demonstrating a particular behaviour in the emission spectra due to the absence or presence of zinc. The tetra-platinum(II)-thiopyridylporphyrins exhibited an increase in the emission quantum yield when compared with the starting thiopyridylporphyrins 1 and 2. Spectroscopic studies of both platinum derivatives reveal their ability to interact unequivocally with DNA from calf thymus and DNA of low molecular weight from salmon sperms, and also with the most abundant protein in human blood plasma, human serum albumin (HSA). Herein, both tetra-platinum(II)-thiopyridylporphyrins 3 and 4 exhibit electrostatic surface binding with the negative phosphate groups of DNA. Similar to cationic-anionic binding with DNA, tetra-platinum(II)-thiopyridylporphyrinato zinc(II) demonstrates a particular binding intercalation mode with DNA. Photophysical studies demonstrated that both porphyrins are photostable and able to generate singlet oxygen ((1)O2) after light irradiation. Exposure of pMT123 plasmid DNA to tetra-platinum(II)-thiopyridylporphyrins and irradiation with light lead to single-strand breakage as determined by the conversion of the supercoiled form of the plasmid (form I) into the nicked circular form (form II). The tetra-platinum(II)-thiopyridylporphyrinato Zn(II) demonstrates a particular intercalation binding mode with DNA and an ability to cleave DNA after photo-excitation.

  14. 2,2,5,7,8-Penta­methyl­chroman-6-yl 2,3,4,6-tetra-O-acetyl-α-d-glucopyran­oside from synchrotron data

    PubMed Central

    Brzezinski, Krzysztof; Wałejko, Piotr; Baj, Aneta; Witkowski, Stanisław; Dauter, Zbigniew

    2011-01-01

    The crystal structure of the title compound, C28H38O11, solved and refined against synchrotron diffraction data, contains two formula units in the asymmetric unit. In both mol­ecules, the dihydro­pyran ring along with its methyl substituents is disordered and adopts two alternative half-chair conformations. The occupancy of the major conformers of the two mol­ecules refined to 0.858 (5) and 0.523 (5). PMID:21522460

  15. Cyclo­hexa­nespiro-2′-[2′,3′,6′,7′-tetra­hydro-1′H-cyclo­penta­[d]pyrimidin]-4′(5′H)-one

    PubMed Central

    Shi, Daxin; Qian, Dongfeng; Zhang, Qi; Li, Jiarong

    2009-01-01

    The title compound, C12H18N2O, was synthesized by the reaction of cyclo­hexa­none and 2-amino­cyclo­pent-1-enecarbonitrile. In the mol­ecule of the title compound, the six-carbon ring displays a chair conformation, the six-membered 1,3-diaza ring and the cyclo­pentene ring both assume envelope conformations. Supra­molecular aggregation is achieved by N—H⋯O hydrogen bonds. PMID:21582267

  16. Tetra-triethyleneoxysulfonyl substituted zinc phthalocyanine for photodynamic cancer therapy.

    PubMed

    Kuzyniak, Weronika; Ermilov, Eugeny A; Atilla, Devrim; Gürek, Ayşe Gül; Nitzsche, Bianca; Derkow, Katja; Hoffmann, Björn; Steinemann, Gustav; Ahsen, Vefa; Höpfner, Michael

    2016-03-01

    Photodynamic therapy (PDT) has emerged as an effective and minimally invasive treatment option for several diseases, including some forms of cancer. However, several drawbacks of the approved photosensitizers (PS), such as insufficient light absorption at therapeutically relevant wavelengths hampered the clinical effectiveness of PDT. Phthalocyanines (Pc) are interesting PS-candidates with a strong light absorption in the favourable red spectral region and a high quantum yield of cancer cell destroying singlet oxygen generation. Here, we evaluated the suitability of tetra-triethyleneoxysulfonyl substituted zinc phthalocyanine (ZnPc) as novel PS for PDT. ZnPc-induced phototoxicity, induction of apoptosis as well as cell cycle arresting effects was studied in the human gastrointestinal cancer cell lines of different origin. Photoactivation of ZnPc-pretreated (1-10 μM) cancer cells was achieved by illumination with a broad band white light source (400-700 nm) at a power density of 10 J/cm(2). Photoactivation of ZnPc-loaded cells revealed strong phototoxic effects, leading to a dose-dependent decrease of cancer cell proliferation of up to almost 100%, the induction of apoptosis and a G1-phase arrest of the cell cycle, which was associated with decrease in cyclin D1 expression. By contrast, ZnPc-treatment without illumination did not induce any cytotoxicity, apoptosis, cell cycle arrest or decreased cell growth. Antiangiogenic effects of ZnPc-PDT were investigated in vivo by performing CAM assays, which revealed a marked degradation of blood vessels and the capillary plexus of the chorioallantoic membrane of fertilized chicken eggs. Based on our data we think that ZnPc may be a promising novel photosensitizer for innovative PDT.

  17. Simulation of the conformation of the murein fabric: the oligoglycan, penta-muropeptide, and cross-linked nona-muropeptide.

    PubMed

    Koch, A L

    2000-12-01

    The structure and conformation of the sacculus of bacteria at a scale much larger than just the component disaccharide penta-muropeptide is not well known and is crucially important for the understanding of bacterial growth and cell wall function. By computer simulations, the minimal energy conformations and the energy needed for stretching the component parts were found. The oligosaccharide chain, modeled as (GlcNAc-MurNAc)8 when under no tension, can assumed a variety of nearly iso-energetic conformations. These included a variety of bends and kinks, with the chain forming an irregular random coil. In the most relaxed and minimal energy state, the D-lactyl groups of the MurNAc (N-acetyl muramic acid) residues protruded at about an angle of 90 degrees relative to the D-lactyl groups of their immediate MurNAc neighbors in the same chain. The cell wall penta-muropeptide precursor is identical for Escherichia coli and Bacillus subtilis; it also adopted many conformations, each of an energy almost equal to the global minimum. The cross-bridged structure of the tail-to-tail linkage of disaccharide nona-muropeptide has a second type of association, in addition to the covalent cross-bridge, which has not been considered before. This is the ionic interaction between the free D-Ala and the free amino group of the m-A2 pm. In vivo, when the cross-bridge is stretched (in the computer to simulate growth), this pairing dissociates. The possible biological significance of this is that it exposes the underlying 'tail-to-tail' peptide bond to autolysis and will expose both the ends of the m-A2 pm and the D-AlaD-Ala groups that may then be able to react with nascent penta-muropeptides to form trimers. This suggests a new model for growth of the bacterial cell wall that depends on changes in the chemical conformation of the cross-bridge structure as it comes to bear stress.

  18. Crystal structure of trans-diammine(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4) N)chromium(III) tetra-chlorido-zincate chloride monohydrate from synchrotron data.

    PubMed

    Moon, Dohyun; Choi, Jong-Ha

    2016-04-01

    The asymmetric unit of the title complex salt, [Cr(C10H24N4)(NH3)2][ZnCl4]Cl·H2O, is comprised of four halves of the Cr(III) complex cations (the counterparts being generated by application of inversion symmetry), two tetra-chlorido-zincate anions, two chloride anions and two water mol-ecules. Each Cr(III) ion is coordinated by the four N atoms of the cyclam (1,4,8,11-tetra-aza-cyclo-tetra-deca-ne) ligand in the equatorial plane and by two N atoms of ammine ligands in axial positions, displaying an overall distorted octa-hedral coordination environment. The Cr-N(cyclam) bond lengths range from 2.0501 (15) to 2.0615 (15) Å, while the Cr-(NH3) bond lengths range from 2.0976 (13) to 2.1062 (13) Å. The macrocyclic cyclam moieties adopt the trans-III conformation with six- and five-membered chelate rings in chair and gauche conformations. The [ZnCl4](2-) anions have a slightly distorted tetra-hedral shape. In the crystal, the Cl(-) anions link the complex cations, as well as the solvent water mol-ecules, through N-H⋯Cl and O-H⋯Cl hydrogen-bonding inter-actions. The supra-molecular set-up also includes N-H⋯Cl, C-H⋯Cl, N-H⋯O and O-H⋯Cl hydrogen bonding between N-H or C-H groups of cyclam, ammine N-H and water O-H donor groups, and O atoms of the water mol-ecules, Cl(-) anions or Cl atoms of the [ZnCl4](2-) anions as acceptors, leading to a three-dimensional network structure. PMID:27375863

  19. Blade loss transient dynamics analysis, volume 2. Task 2: TETRA 2 user's manual

    NASA Technical Reports Server (NTRS)

    Black, Gerald; Gallardo, Vincente C.

    1986-01-01

    This is the user's manual for the TETRA 2 Computer Code, a program developed in the NASA-Lewis Blade Loss Program. TETRA 2 calculates a turbine engine's dynamic structural response from applied stimuli. The calculation options are: (1) transient response; and (2) steady state forced response. Based on the method of modal syntheses, the program allows the use of linear, as well as nonlinear connecting elements. Both transient and steady state options can include: flexible Bladed Disk Module, and Nonlinear Connecting Elements (including deadband, hardening/softening spring). The transient option has the additional capability to calculate response with a squeeze film bearing module. TETRA 2 output is summarized in a plotfile which permits post processing such as FFT or graphical animation with the proper software and computer equipment.

  20. (η(4)-Cyclo-octa-tetra-ene)(η(8)-cyclo-octa-tetra-ene)iodido-tantalum(V).

    PubMed

    Verma, Pratik; Sussman, Victor J; Brennessel, William W; Ellis, John E

    2014-07-01

    The title complex, [Ta(η(4)-C8H8)(η(8)-C8H8)I], lies across a crystallographic mirror plane that includes the Ta(V) atom and the iodide ligand. One cyclo-octa-tetra-ene (cot) ring is η(4)-coordinating and is bis-ected by the mirror plane. The fold angle between the plane of the coordinating butadiene portion and the middle plane of the ring is 27.4 (4)°. An additional minor fold angle of 9.3 (7)° exists between the final plane in the ring and the middle plane. The other cot ring is η(8)-coordinating and is also cut by the mirror plane. In this case, the ring is disordered over the mirror plane, and one position is modeled with appropriate restraints and constraints with respect to distances, angles and displacement parameters (the second position is generated by symmetry). This ring is nearly planar, with an r.m.s. deviation of only 0.05 Å when all eight C atoms are included in the calculation. Pairs of inter-molecular η(8)-cot rings are parallel stacked and slightly off center, with a centroid-centroid distance of 3.652 Å. No other significant inter-molecular inter-actions are observed. The compound is of inter-est as the first structurally characterized mixed halogen-cot complex of the group 5 metals and contains the longest terminal Ta-I distance [3.0107 (5) Å] reported to date. PMID:25161515

  1. Structural, DFT and biological studies on Co(II) complexes of semi and thiosemicarbazide ligands derived from diketo hydrazide

    NASA Astrophysics Data System (ADS)

    Yousef, T. A.; El-Gammal, O. A.; Ahmed, Sara F.; Abu El-Reash, G. M.

    2014-11-01

    Three ligands have been prepared by addition ethanolic suspension of 2-hydrazino-2-oxo-N-phenyl-acetamide to phenyl isocyanate (H2PAPS), phenyl isothiocyanate (H2PAPT) and benzoyl isothiocyanate (H2PABT). The Co(II) chloride complexes were prepared and characterized by conventional techniques. The isolated complexes were assigned the formulaes, [Co(HPAPS)Cl(H2O)2]H2O, [Co(HPAPT)Cl]H2O and [Co(H2PABT)Cl2], respectively. The IR spectra of complexes shows that H2PAPS behaves as a mononegative tridentate via CO of hydrazide moiety and enolized CO of hydrazide moiety and CN (azomethine) group due to enolization of CO isocyanate moiety. H2PAPT behaves as mononegative tridentate via one CO of hydrazide moiety and thiol CS and NH groups and finally H2PABT behaves as neutral tetradentate via one CO of hydrazide moiety, CO of benzoyl moiety, Cdbnd S due to enolization of the second CO of hydrazide moiety and new CN (azomethine) groups. The vibrational frequencies of the IR spectra of ligands which were determined experimentally are compared with those obtained theoretically from DFT calculations. Also, the bond lengths, bond angles, HOMO, LUMO and dipole moments have been calculated. The calculated HOMO-LUMO energy gap reveals that charge transfer occurs within the ligand molecules. The calculated values of binding energies indicates the stability of metal complexes is higher that of ligand. Also, the kinetic and thermodynamic parameters for the different thermal degradation steps of the complexes were determined by Coats-Redfern and Horowitz-Metzger methods. The antibacterial activities were also tested against Bacillus subtilis and Escherichia coli bacteria. The free ligands showed a higher antibacterial effect than their Co(II) complexes except [Co(HPAPS)Cl(H2O)2]H2O which shows higher activity than corresponding ligand. The antitumor activities of the Ligands and their Co(II) complexes have been evaluated against liver (HePG2) and breast (MCF-7) cancer cells. All ligands

  2. Co(II) PCP Pincer Complexes as Catalysts for the Alkylation of Aromatic Amines with Primary Alcohols.

    PubMed

    Mastalir, Matthias; Tomsu, Gerald; Pittenauer, Ernst; Allmaier, Günter; Kirchner, Karl

    2016-07-15

    Efficient alkylations of amines by alcohols catalyzed by well-defined Co(II) complexes are described that are stabilized by a PCP ligand (N,N'-bis(diisopropylphosphino)-N,N'-dimethyl-1,3-diaminobenzene) based on the 1,3-diaminobenzene scaffold. This reaction is an environmentally benign process implementing inexpensive, earth-abundant nonprecious metal catalysts and is based on the acceptorless alcohol dehydrogenation concept. A range of primary alcohols and aromatic amines were efficiently converted into mono-N-alkylated amines in good to excellent isolated yields. PMID:27356282

  3. (2R*,4R*,7S*,10R*,12R*)-3,11,13,15-Tetra­oxa­penta­cyclo­[5.5.3.01,7.02,4.010,12]penta­deca-5,8-dien-14-one

    PubMed Central

    Mehta, Goverdhan; Sen, Saikat; Kumar, C. S. Ananda

    2013-01-01

    The title compound, C11H8O5, features a ‘skipped’ diene, an anti-bis­(epoxide) and a cyclic carbonate, all embedded in a densely functionalized [4.4.3]propellane scaffold. The crystal packing of this diepoxide is effected primarily by C—H⋯O hydrogen bonds, which link the mol­ecules into tapes along the b axis. Inter-tape connectivity is brought about by centrosymmetrically disposed pairs of C⋯O contacts [3.183 (4) Å] between the Cδ+=Oδ- dipoles of neighbouring carbonate moieties. PMID:24098200

  4. Bis(di­methyl­formamide)­penta­kis­(μ-N,2-dioxido­benzene-1-carb­ox­imidato)tetra­kis­(1-methyl­imidazole)di-μ-propionato-penta­manganese(III)manganese(II)–di­methyl­formamide–methanol (1/0.24/1.36)

    PubMed Central

    Lutter, Jacob C.; Kampf, Jeff W.; Zeller, Matthias; Zaleski, Curtis M.

    2013-01-01

    The title compound [Mn6(C7H4NO3)5(C3H5O2)2(C4H6N2)4.17(C3H7NO)1.83]·0.24C3H7NO·1.36CH3OH or Mn(II)(C3H5O2)2[15-MCMn(III)N(shi)-5](Me—Im)4.17(DMF)1.83·0.24DMF·1.36MeOH (where MC is metallacrown, shi3− is salicyl­hydroximate, Me—Im is 1-methyl­imidazole, DMF is N,N-di­methyl­formamide, and MeOH is methanol), contains an MnII ion in the central cavity and five MnIII ions in the MC ring. The central MnII ion is seven coordinate and has a geometry best described as distorted face-capped trigonal prismatic with Φ angles of 6.13, 10.36, and 11.73° and an estimated average s/h ratio of 1.03±0.11. Four of the ring MnIII ions are six coordinate with distorted octa­hedral geometries. Two of the MnIII ions have Λ absolute stereoconfiguration, while the other two MnIII ions have a planar configuration. The fifth MnIII ion is five coordinate and has a distorted square pyramidal geometry with τ = 0.20. Three of the MnIII ions bind one 1-methyl­imidazole ligand. Two of the ring MnIII ions have a 1-methyl­imidazole and a DMF disordered over a coordination site. For one of the ring MnIII ions, the occupancy ratio of the ligands refines to 0.51 (1):0.49 (1) in favor of the DMF. For the other ring MnIII ion, the occupancy ratio of the ligands refines to 0.68 (1):0.32 (1) in favor of the 1-methyl­imidazole. Two propionate anions serve to bridge the central MnII ion between two different MnIII ions. The methyl groups of the bridging propionate anions are disordered over two positions. The methyl group disorder also induces disorder in the H atoms of the adjacent methyl­ene C atom to the same degree. For one of the propionate anions, the occupancy ratio refines to 0.752 (8):0.248 (8) and for the second, the occupancy ratio refines to 0.604 (6):0.396 (6). In addition, the disorder of the methyl group of the latter propionate anion is correlated with a partially occupied [0.604 (6)] methanol mol­ecule. Furthermore, a methanol mol­ecule and a DMF mol­ecule are positionally disordered in the lattice. The occupancy refines to 0.757 (7):0.243 (7) in favor of the methanol mol­ecule. Correlated to the occupancy of the methanol and DMF mol­ecules is a disordered benzene ring of one salicyl­hydroximate ligand. The benzene ring is disordered over two positions with an occupancy ratio of 0.757 (7):0.243 (7). Lastly, the two lattice methanol mol­ecules are hydrogen bonded to the 15-MC-5 mol­ecule. For the partially occupied methanol mol­ecule associated with the disordered propionate anion, the hydroxyl group of the methanol is hydrogen bonded to a carboxyl­ate O atom of the propionate anion. For the partially occupied methanol mol­ecule associated with the partially occupied lattice DMF mol­ecule, the hydroxyl group of the methanol is hydrogen bonded to the phenolate O atom of a salicyl­hydroximate ligand and to the carbonyl O atom of a coordinated DMF mol­ecule. PMID:24426984

  5. 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

  6. 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. PMID:25878828

  7. Public health assessment for Penta Wood Products Incorporated, Siren, Burnett County, Wisconsin, Region 5. Cerclis No. WID006176945. Preliminary report

    SciTech Connect

    1996-10-02

    Penta Wood Products Superfund National Priorities List (NPL) site is a part of the Agency for Toxic Substances and Disease Registry (ATSDR) Public Health Assesment Enhancement Initiative. This document indicates what actions the DOH and ATSDR have taken to address the elements required by Section 104(I)(6)(A) of the comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) as amended (42 U.S.C. 9604(I)(6)(A)). Those elements are: (1) Nature and extent of contamination; (2) Potential pathways of human exposure; (3) Demographics (size and susceptibility of nearby populations); (4) Health hazards of the site; and (5) Comparison of morbidity and mortality data. In addition, this document indicates how the DOH and ATSDR provided earlier, specifically targeted evaluations. DOH`s future plans at this site are also presented in this document.

  8. Synthesis and spectroscopic studies of novel Cu(II), Co(II), Ni(II) and Zn(II) mixed ligand complexes with saccharin and nicotinamide

    NASA Astrophysics Data System (ADS)

    Çakır, S.; Bulut, İ.; Naumov, P.; Biçer, E.; Çakır, O.

    2001-01-01

    Four novel mixed ligand complexes of Cu(II), Co(II), Ni(II) and Zn(II) with saccharin and nicotinamide were synthesised and characterised on the basis of elemental analysis, FT-IR spectroscopic study, UV-Vis spectrometric and magnetic susceptibility data. The structure of the Cu (II) complex is completely different from those of the Co(II), Ni(II) and Zn(II) complexes. From the frequencies of the saccharinato CO and SO 2 modes, it has been proven that the saccharinato ligands in the structure of the Cu complex are coordinated to the metal ion ([Cu(NA) 2(Sac) 2(H 2O)], where NA — nicotinamide, Sac — saccharinato ligand or ion), whilst in the Co(II), Ni(II) and Zn(II) complexes are uncoordinated and exist as ions ([M(NA) 2(H 2O) 4](Sac) 2).

  9. Blade loss transient dynamics analysis, volume 1. Task 2: TETRA 2 theoretical development

    NASA Technical Reports Server (NTRS)

    Gallardo, Vincente C.; Black, Gerald

    1986-01-01

    The theoretical development of the forced steady state analysis of the structural dynamic response of a turbine engine having nonlinear connecting elements is discussed. Based on modal synthesis, and the principle of harmonic balance, the governing relations are the compatibility of displacements at the nonlinear connecting elements. There are four displacement compatibility equations at each nonlinear connection, which are solved by iteration for the principle harmonic of the excitation frequency. The resulting computer program, TETRA 2, combines the original TETRA transient analysis (with flexible bladed disk) with the steady state capability. A more versatile nonlinear rub or bearing element which contains a hardening (or softening) spring, with or without deadband, is also incorporated.

  10. Management of oral pyogenic granuloma with sodium tetra decyl sulphate. A case series.

    PubMed

    Samatha, Y; Reddy, T Harshavardhan; Jyothirrmai; Ravikiran, A; Sankar, A J Sai

    2013-01-01

    Pyogenic granuloma, or granuloma pyogenicum, is a common, tumor-like growth of the oral cavity or skin that is considered to be an exaggerated, localized connective tissue reaction to a minor injury or irritation. A total of five clinical cases of oral pyogenic granuloma were randomly selected in the age group between 26 and 41 years. All these cases were treated with sodium tetra decyl sulphate and examined for regression and reccurrence of the lesion for six months. Various treatment modalities consist of conservative surgical excision, cryosurgery, laser surgery and sclerotherapy. Sclerotherapy with sodium tetra decyl sulphate is a relatively simple and effective method for treating oral pyogenic granuloma.

  11. Single-ion-magnet behavior in a two-dimensional coordination polymer constructed from Co(II) nodes and a pyridylhydrazone derivative.

    PubMed

    Liu, Xiangyu; Sun, Lin; Zhou, Huiliang; Cen, Peipei; Jin, Xiaoyong; Xie, Gang; Chen, Sanping; Hu, Qilin

    2015-09-21

    A novel two-dimensional (2D) coordination polymer, [Co(ppad)2]n (1), resulted from the assembly of Co(II) ions based on a versatile ligand termed N(3)-(3-pyridoyl)-3-pyridinecarboxamidrazone. Alternating/direct-current magnetic studies of compound 1 indicate that the spatially separated high-spin Co(II) ions act as single-ion magnets (SIMs). The present work represents the first case of a 2D Co(II)-based SIM composed of a monocomponent organic spacer.

  12. Synthesis, Structure, and Reactivity of Co(II) and Ni(II) PCP Pincer Borohydride Complexes

    PubMed Central

    2015-01-01

    The 15e square-planar complexes [Co(PCPMe-iPr)Cl] (2a) and [Co(PCP-tBu)Cl] (2b), respectively, react readily with NaBH4 to afford complexes [Co(PCPMe-iPr)(η2-BH4)] (4a) and [Co(PCP-tBu)(η2-BH4)] (4b) in high yields, as confirmed by IR spectroscopy, X-ray crystallography, and elemental analysis. The borohydride ligand is symmetrically bound to the cobalt center in η2-fashion. These compounds are paramagnetic with effective magnetic moments of 2.0(1) and 2.1(1) μB consistent with a d7 low-spin system corresponding to one unpaired electron. None of these complexes reacted with CO2 to give formate complexes. For structural and reactivity comparisons, we prepared the analogous Ni(II) borohydride complex [Ni(PCPMe-iPr)(η2-BH4)] (5) via two different synthetic routes. One utilizes [Ni(PCPMe-iPr)Cl] (3) and NaBH4, the second one makes use of the hydride complex [Ni(PCPMe-iPr)H] (6) and BH3·THF. In both cases, 5 is obtained in high yields. In contrast to 4a and 4b, the borohydride ligand is asymmetrically bound to the nickel center but still in an η2-mode. [Ni(PCPMe-iPr)(η2-BH4)] (5) loses readily BH3 at elevated temperatures in the presence of NEt3 to form 6. Complexes 5 and 6 are both diamagnetic and were characterized by a combination of 1H, 13C{1H}, and 31P{1H} NMR, IR spectroscopy, and elemental analysis. Additionally, the structure of these compounds was established by X-ray crystallography. Complexes 5 and 6 react with CO2 to give the formate complex [Ni(PCPMe-iPr)(OC(C=O)H] (7). The extrusion of BH3 from [Co(PCPMe-iPr)(η2-BH4)] (4a) and [Ni(PCPMe-iPr)(η2-BH4)] (5) with the aid of NH3 to yield the respective hydride complexes [Co(PCPMe-iPr)H] and [Ni(PCPMe-iPr)H] (6) and BH3NH3 was investigated by DFT calculations showing that formation of the Ni hydride is thermodynamically favorable, whereas the formation of the Co(II) hydride, in agreement with the experiment, is unfavorable. The electronic structures and the bonding of the borohydride ligand in [Co

  13. Ethane-1,2-diaminium bis­{5-[4-(1H-tetra­zol-5-yl)phen­yl]tetra­zolide} dihydrate

    PubMed Central

    Li, Chun-Rong; Xia, Zheng-Qiang

    2011-01-01

    In the two anions of the title salt, C2H10N2 2+·2C8H5N8 −·2H2O, the central aromatic rings make dihedral angles of 13.53 (6) and 6.53 (7)° with the deprotonated tetra­zole rings, and 11.39 (6) and 10.41 (9)° with the other tetra­zole groups. In the crystal, the cations, anions and water mol­ecules are linked by an extensive O—H⋯N, N—H⋯O and N—H⋯N hydrogen-bond network into two-dimensional wave-like duplex sheets extending parallel to the bc plane. π–π stacking inter­actions between benzene rings [inter­centroid distances are 3.8482 (4) and 3.9621 (5) Å] and between tetra­zole rings [inter­centroid distances are 3.4350 (4) and 3.7169 (4) Å] further consolidate the crystal structure. PMID:22059036

  14. Probing bistability in Fe(II) and Co(II) complexes with an unsymmetrically substituted quinonoid ligand.

    PubMed

    van der Meer, Margarethe; Rechkemmer, Yvonne; Breitgoff, Frauke D; Dechert, Sebastian; Marx, Raphael; Dörfel, María; Neugebauer, Petr; van Slageren, Joris; Sarkar, Biprajit

    2016-05-28

    The generation of molecular platforms, the properties of which can be influenced by a variety of external perturbations, is an important goal in the field of functional molecular materials. We present here the synthesis of a new quinonoid ligand platform containing an [O,O,O,N] donor set. The ligand is derived from a chloranilic acid core by using the [NR] (nitrogen atom with a substituent R) for [O] isoelectronic substitution. Mononuclear Fe(II) and Co(II) complexes have been synthesized with this new ligand. Results obtained from single crystal X-ray crystallography, NMR spectroscopy, (spectro)electrochemistry, SQUID magnetometry, multi-frequency EPR spectroscopy and FIR spectroscopy are used to elucidate the electronic and geometric structures of the complexes. Furthermore, we show here that the spin state of the Fe(II) complex can be influenced by temperature, pressure and light and the Co(II) complex displays redox-induced spin-state switching. Bistability is observed in the solid-state as well as in solution for the Fe(II) complex. The new ligand presented here, owing to the [NR] group present in it, will likely have more adaptability while investigating switching phenomena compared to its [O,O,O,O] analogues. Thus, such classes of ligands as well as the results obtained on the reversible changes in physical properties of the metal complexes are likely to contribute to the generation of multifunctional molecular materials. PMID:27109712

  15. Iron Oxide Impregnated Morus alba L. Fruit Peel for Biosorption of Co(II): Biosorption Properties and Mechanism

    PubMed Central

    Koduru, Janardhan Reddy; Chang, Yoon-Young; Yang, Jae-Kyu; Kim, Im-Soon

    2013-01-01

    Biosorption is an ecofriendly wastewater treatment technique with high efficiency and low operating cost involving simple process for the removal of heavy metal ions from aqueous solution. In the present investigation, Morus alba L. fruit peel powder (MAFP) and iron oxide impregnated Morus alba L. fruit peel powder (IO-MAFP) were prepared and used for treating Co(II) contaminated aqueous solutions. Further the materials were characterized by using FTIR and SEM-EDX analysis. From FT-IR analysis it was found that hydroxyl, methoxy, and carbonyl groups are responsible for Co(II) biosorption. The kinetic data obtained for both biosorbents was well fitted with pseudo-second-order kinetic model. The equilibrium data was in tune with the Langmuir and Freundlich isotherm models. The thermodynamic studies were also carried and it was observed that sorption process was endothermic at 298–328 K. These studies demonstrated that both biosorbents were promising, efficient, economic, and biodegradable sorbents. PMID:24324384

  16. Removal of Co(II) from waste water using dry cow dung powder : a green ambrosia to soil

    NASA Astrophysics Data System (ADS)

    Bagla, Hemlata; Khilnani, Roshan

    2015-04-01

    Co(II) is one of the hazardous products found in the waste streams. The anthropogenic activities are major sources of Co(II) in our environment. Some of the well-established processes such as chemical precipitation, membrane process, liquid extraction and ion exchange have been applied as a tool for the removal of this metal ion [1]. All the above methods are not considered to be greener due to some of their shortcomings such as incomplete metal ion removal, high requirement of energy and reagents, generation of toxic sludge or other waste materials which in turn require further treatments for their cautious disposal. The present investigation entails the application of dry cow dung powder (DCP) as an indigenous, inexpensive and eco-friendly material for the removal of Co(II) from aqueous medium. DCP, is naturally available bio-organic, complex, polymorphic humified fecal matter of cow and is enriched with minerals, carbohydrates, fats, proteins, bile pigments, aliphatic-aromatic species such as 'Humic acid' (HA), Fulvic acid, Ulmic acid [2,3]. Batch biosorption experiments were conducted employing 60Co(II) as a tracer and effect of various process parameters such as pH (1-8), temperature (283-363K), amount of biosorbent (5-40 g/L), time of equilibration (0-30 min), agitation speed (0-4000 rpm), concentration of initial metal ions (0.5-20 mg/mL) and interfering effect of different organic as well as inorganic salts were studied. The Kinetic studies were carried out employing various models but the best fitting was given by Lagergren Pseudo-second order model [4] with high correlation coefficient R2 value of 0.999 and adsorption capacity of 2.31 mg/g. The thermodynamic parameters for biosorption were also evaluated which indicated spontaneous and exothermic process with high affinity of DCP for Co(II). Many naturally available materials are used for biosorption of hazardous metal pollutants, where most of them are physically or chemically modified. In this research

  17. Tetrahymena functional genomics database (TetraFGD): an integrated resource for Tetrahymena functional genomics.

    PubMed

    Xiong, Jie; Lu, Yuming; Feng, Jinmei; Yuan, Dongxia; Tian, Miao; Chang, Yue; Fu, Chengjie; Wang, Guangying; Zeng, Honghui; Miao, Wei

    2013-01-01

    The ciliated protozoan Tetrahymena thermophila is a useful unicellular model organism for studies of eukaryotic cellular and molecular biology. Researches on T. thermophila have contributed to a series of remarkable basic biological principles. After the macronuclear genome was sequenced, substantial progress has been made in functional genomics research on T. thermophila, including genome-wide microarray analysis of the T. thermophila life cycle, a T. thermophila gene network analysis based on the microarray data and transcriptome analysis by deep RNA sequencing. To meet the growing demands for the Tetrahymena research community, we integrated these data to provide a public access database: Tetrahymena functional genomics database (TetraFGD). TetraFGD contains three major resources, including the RNA-Seq transcriptome, microarray and gene networks. The RNA-Seq data define gene structures and transcriptome, with special emphasis on exon-intron boundaries; the microarray data describe gene expression of 20 time points during three major stages of the T. thermophila life cycle; the gene network data identify potential gene-gene interactions of 15 049 genes. The TetraFGD provides user-friendly search functions that assist researchers in accessing gene models, transcripts, gene expression data and gene-gene relationships. In conclusion, the TetraFGD is an important functional genomic resource for researchers who focus on the Tetrahymena or other ciliates. Database URL: http://tfgd.ihb.ac.cn/

  18. Isopropyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyran­oside

    PubMed Central

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

    2013-01-01

    The title compound, C17H26O10, was formed by a Koenigs–Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide and propan-2-ol. The central ring adopts a chair conformation. The crystal does not contain any significant inter­molecular inter­actions. PMID:23424447

  19. A new tetra-primer ARMS-PCR for genotyping bovine kappa-casein polymorphisms.

    PubMed

    Fonseca, P A S; Rosse, I C; Demiranda, M; Machado, M A; Verneque, R S; Peixoto, M G C D; Carvalho, M R S

    2013-12-11

    Kappa-casein (κ-casein) is one of the most abundant milk proteins. Its main function is to avoid the aggregation of casein micelles, keeping them, and therefore calcium phosphate, in pockets in solution. In bovines, a κ-casein functional polymorphism has been associated with fat, calcium, and protein milk contents and faster curd contraction in cheese production. Quicker curd contraction reduces the loss of milk solids, enhancing cheese yield. This polymorphism induces a double amino acid substitution (Thr136Ile and Ala148Asp). The polymorphism is normally detected by PCR-RFLP, which is a laborious method. An interesting methodological alternative is the tetra-primer amplification refractory mutation system PCR (tetra-primer ARMS-PCR). A tetra-primer ARMS-PCR for the detection of this κ-casein polymorphism has been described. However, specificity was not achieved, probably due to problems with primer design. We developed a new tetra-primer ARMS-PCR for the detection of the κ-casein polymorphism. This new method was validated in a double-blind test, by comparison with the results obtained for 50 Guzerá bulls formerly genotyped by PCR-RFLP. This new method achieved 100% sensitivity and specificity. We conclude that this method is a useful, cost-efficient alternative for the detection of functional κ-casein polymorphisms.

  20. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Derivative of tetra-chloro-ethy-lene. 721.3560 Section 721.3560 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.3560 Derivative...

  1. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Health Administration regulations and set forth at 29 CFR 1910.134, and 30 CFR part 11, respectively, and... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Derivative of tetra-chloro-ethy-lene. 721.3560 Section 721.3560 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  2. 21 CFR 177.1660 - Poly (tetra-methyl-ene tere-phtha-late).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Poly (tetra-methyl-ene tere-phtha-late). 177.1660 Section 177.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use...

  3. 21 CFR 177.1660 - Poly (tetra-methylene tereph-thalate).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Poly (tetra-methylene tereph-thalate). 177.1660 Section 177.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and Repeated...

  4. Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

    SciTech Connect

    Long, Yan; Lin, Zuoxian; Xia, Menghang; Zheng, Wei; Li, Zhiyuan

    2013-03-01

    Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependent inhibitions of HERG channel currents with IC{sub 50} values of 4 nM and 17 nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I–V curves in a hyperpolarized direction for 10–15 mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I–V curve in a hyperpolarized direction for 24.4 mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners. - Highlights: ► Tetra-n-octylammonium and benzethonium are potent HERG channel inhibitors. ► Channel activation and inactivation processes are accelerated by the two compounds. ► Both compounds are the open-channel blockers to HERG channels. ► HERG channel inhibition by both compounds is use-, voltage- and state dependent. ► The in vivo risk of QT prolongation needs to be studied for the two compounds.

  5. Crystal structure of trans-diammine(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4 N)chromium(III) tetra­chlorido­zincate chloride monohydrate from synchrotron data

    PubMed Central

    Moon, Dohyun; Choi, Jong-Ha

    2016-01-01

    The asymmetric unit of the title complex salt, [Cr(C10H24N4)(NH3)2][ZnCl4]Cl·H2O, is comprised of four halves of the CrIII complex cations (the counterparts being generated by application of inversion symmetry), two tetra­chlorido­zincate anions, two chloride anions and two water mol­ecules. Each CrIII ion is coordinated by the four N atoms of the cyclam (1,4,8,11-tetra­aza­cyclo­tetra­deca­ne) ligand in the equatorial plane and by two N atoms of ammine ligands in axial positions, displaying an overall distorted octa­hedral coordination environment. The Cr—N(cyclam) bond lengths range from 2.0501 (15) to 2.0615 (15) Å, while the Cr—(NH3) bond lengths range from 2.0976 (13) to 2.1062 (13) Å. The macrocyclic cyclam moieties adopt the trans-III conformation with six- and five-membered chelate rings in chair and gauche conformations. The [ZnCl4]2− anions have a slightly distorted tetra­hedral shape. In the crystal, the Cl− anions link the complex cations, as well as the solvent water mol­ecules, through N—H⋯Cl and O—H⋯Cl hydrogen-bonding inter­actions. The supra­molecular set-up also includes N—H⋯Cl, C—H⋯Cl, N—H⋯O and O—H⋯Cl hydrogen bonding between N—H or C—H groups of cyclam, ammine N—H and water O—H donor groups, and O atoms of the water mol­ecules, Cl− anions or Cl atoms of the [ZnCl4]2− anions as acceptors, leading to a three-dimensional network structure. PMID:27375863

  6. Frequency-switching inversion-recovery for severely hyperfine-shifted NMR: evidence of asymmetric electron relaxation in high-spin Co(II).

    PubMed

    Riley, Erin A; Petros, Amy K; Smith, Karen Ann; Gibney, Brian R; Tierney, David L

    2006-12-11

    A new method for reliably measuring longitudinal relaxation rates for severely hyperfine-shifted NMR signals in aqueous solutions is presented. The method is illustrated for a well-defined cobalt tetracysteinate, with relevance to cobalt-substituted metalloproteins. The relaxation measurements are indicative of asymmetric electronic relaxation of the high-spin Co(II) ion.

  7. Highly stable water dispersible calix[4]pyrrole octa-hydrazide protected gold nanoparticles as colorimetric and fluorometric chemosensors for selective signaling of Co(II) ions.

    PubMed

    Bhatt, Keyur D; Vyas, Disha J; Makwana, Bharat A; Darjee, Savan M; Jain, Vinod K

    2014-01-01

    Water dispersible stable gold nanoparticles (AuNps) have been synthesized by using calix[4]pyrrole octa-hydrazide (CPOH) as a reducing as well as stabilizing agent. CPOH-AuNps have been characterized by surface plasmon resonance, particle size analyzer and transmission electron microscopy. CPOH-AuNps are water dispersible, highly stable for more than 150 days at neutral pH with a size of less than 10nm and zeta potential of 15±2 MeV. Ion sensing property of CPOH-AuNps has been investigated for various metal ions Pb(II), Cd(II), Mn(II), Fe(III), Ni(II), Zn(II), Hg(II), Co(II) and Cu(II) by colorimetry and spectrofluorimetry. Among all the metal ions investigated, only Co(II) ions gives sharp colour change from ruby red to blue and is easily detectable by naked-eye. CPOH-AuNps being fluorescent in nature also shows great sensitivity and selectivity for Co(II) ions. Co(II) ions can be selectively detected at very low concentration level of 1 nM in a facile way of fluorescence quenching.

  8. Highly stable water dispersible calix[4]pyrrole octa-hydrazide protected gold nanoparticles as colorimetric and fluorometric chemosensors for selective signaling of Co(II) ions

    NASA Astrophysics Data System (ADS)

    Bhatt, Keyur D.; Vyas, Disha J.; Makwana, Bharat A.; Darjee, Savan M.; Jain, Vinod K.

    2014-03-01

    Water dispersible stable gold nanoparticles (AuNps) have been synthesized by using calix[4]pyrrole octa-hydrazide (CPOH) as a reducing as well as stabilizing agent. CPOH-AuNps have been characterized by surface plasmon resonance, particle size analyzer and transmission electron microscopy. CPOH-AuNps are water dispersible, highly stable for more than 150 days at neutral pH with a size of less than 10 nm and zeta potential of 15 ± 2 MeV. Ion sensing property of CPOH-AuNps has been investigated for various metal ions Pb(II), Cd(II), Mn(II), Fe(III), Ni(II), Zn(II), Hg(II), Co(II) and Cu(II) by colorimetry and spectrofluorimetry. Among all the metal ions investigated, only Co(II) ions gives sharp colour change from ruby red to blue and is easily detectable by naked-eye. CPOH-AuNps being fluorescent in nature also shows great sensitivity and selectivity for Co(II) ions. Co(II) ions can be selectively detected at very low concentration level of 1 nM in a facile way of fluorescence quenching.

  9. DNA binding, photoactivated DNA cleavage and cytotoxic activity of Cu(II) and Co(II) based Schiff-base azo photosensitizers

    NASA Astrophysics Data System (ADS)

    Pradeepa, S. M.; Bhojya Naik, H. S.; Vinay Kumar, B.; Indira Priyadarsini, K.; Barik, Atanu; Prabhakara, M. C.

    2015-04-01

    A new class of Cu(II) and Co(II) complexes of azo-containing Schiff base of the type [Cu(L1)2] and [Co(L1)2], where L1 = 4-[(E)-{2-hydroxy-3-[(E)-(4-bromophenyl)diazenyl]benzylidene}amino]benzoic acid have been synthesized and characterized. Extension of conjugation and the presence of free carboxylic acid group of the ligand L1 increased the wavelength of the complexes from visible region to the near IR region (620-850 nm). The Cu(II) and Co(II) complexes interacted with CT-DNA via intercalative mode with the respective Kb value of 3.2 × 104 M-1 and 2.9 × 104 M-1 and acted as proficient photocleavers of SC pUC19 DNA in UV-A light, forming 1O2 as the reactive oxygen species with the quantum yield of 0.38 and 0.36, respectively. Furthermore, the Cu(II) and Co(II) complexes showed photocytotoxicity toward two selected tumor cell lines MCF-7 and A549 by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) method, and the Cu(II) complex exhibits higher photocytotoxicity than Co(II) complex against each of the selected cell lines, this result is identical with their DNA binding ability order.

  10. Hydrothermal self-assembly and supercapacitive behaviors of Co(II) ion-modified graphene aerogels in H{sub 2}SO{sub 4} electrolyte

    SciTech Connect

    Bao, Qi; Hui, K.N.; Hui, K.S.; Wang, Yi; Hong, Xiaoting

    2014-08-15

    Highlights: • 3D Co(II) ions modified graphene aerogels were prepared by one-step hydrothermal process. • The aerogel electrodes showed hybrid supercapacitor behaviors. • The aerogel electrodes exhibited high rate capability and long-term cycling stability. - Abstract: Reduced graphene oxide (r-GO) aerogels decorated with divalent cobalt ions were synthesized via a one-pot hydrothermal self-assembly route. The interaction of Co(II) ions with 3D r-GO aerogels was investigated by spectroscopic techniques, including Raman, attenuated total reflectance infrared, and X-ray photoelectron spectroscopies. The excellent electrochemical properties of the aerogels were confirmed by cyclic voltammetry, galvanostatic charge/discharge tests, and electrochemical impedance spectroscopy in an acid electrolyte (1 M H{sub 2}SO{sub 4}). The Co(II) ion-modified r-GO aerogels can be used as high-performance hybrid supercapacitor materials with a specific capacitance of 387.2 F g{sup –1} at 1 A g{sup –1} current density and a good cycling stability without capacity decay over 1000 cycles. The mechanical integrity enhancement of the hybrid r-GO aerogel framework and the improvement in its unique capacitive performance are attributed to the efficient interconnection produced by electro-active Co(II) ions.

  11. Ferromagnetic coupling mediated by Coπ non-covalent contacts in a pentacoordinate Co(ii) compound showing field-induced slow relaxation of magnetization.

    PubMed

    Nemec, I; Herchel, R; Trávníček, Z

    2016-08-01

    [Co(II)(dpt)(NCS)2], where dpt = bis(3-aminopropyl)amine, was identified as a pentacoordinate Co(II) compound showing field-induced slow relaxation of magnetization. Furthermore, intermolecular ferromagnetic coupling mediated by Coπ non-covalent contacts, where π orbitals originate from the thiocyanato ligand, is reported for the first time. PMID:27435418

  12. Crystal structure of (1,3-di-tert-butyl-η(5)-cyclo-penta-dien-yl)tri-methyl-hafnium(IV).

    PubMed

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos

    2015-05-01

    The mol-ecule of the title organometallic hafnium(IV) com-pound, [Hf(CH3)3(C13H21)] or [HfMe3(η(5)-C5H3-1,3- (t) Bu2)], adopts the classical three-legged piano-stool geometry for mono-cyclo-penta-dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo-penta-dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter-molecular inter-actions present between the mol-ecules in the crystal structure.

  13. Crystal structure of (1,3-di-tert-butyl-η5-cyclo­penta­dien­yl)tri­methyl­hafnium(IV)

    PubMed Central

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos

    2015-01-01

    The mol­ecule of the title organometallic hafnium(IV) com­pound, [Hf(CH3)3(C13H21)] or [HfMe3(η5-C5H3-1,3-tBu2)], adopts the classical three-legged piano-stool geometry for mono­cyclo­penta­dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo­penta­dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter­molecular inter­actions present between the mol­ecules in the crystal structure. PMID:25995884

  14. Secondary ligand-directed assembly of Co(II) coordination polymers based on a pyridine carboxylate ligand

    SciTech Connect

    Cao, Ke-Li; Zhang, Yi-Ping; Cai, Yi-Ni; Xu, Xiao-Wei; Feng, Yun-Long

    2014-07-01

    To investigate the influence of hydrogen bonds and secondary ligands on the structures and properties of the resulting frameworks, five new Co(II) compounds have been synthesized by the reactions of Co(II) salts and 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL) with four rationally selected dicarboxylic acid ligands. Without secondary ligand, we got one compound [CoL{sub 2}(H{sub 2}O){sub 2}]{sub n}·2nH{sub 2}O (1), which possesses a 1D chain structure. In the presence of ancillary ligands, namely, 1,3-adamantanedicarboxylic acid (H{sub 2}adbc), terephthalic acid (H{sub 2}tpa), thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) and 1,4-benzenedithioacetic acid (H{sub 2}bdtc), four 3D structures [Co{sub 2}L{sub 2}(adbc)]{sub n}·nH{sub 2}O (2), [Co{sub 2}L{sub 2}(tpa)]{sub n} (3), [Co{sub 2}L{sub 2}(tdc)]{sub n} (4), [Co{sub 2}L{sub 2}(bdtc)(H{sub 2}O)]{sub n} (5) were obtained, respectively. It can be observed from the architectures of 1–5 that hydrogen bonds and secondary ligands both have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. The XRPD, TGA data of title polymers and the magnetic properties for 2 and 5 have also been investigated. - Graphical abstract: The structural differences show that the ancillary ligands have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. - Highlights: • Five new Co(II) coordination polymers have been synthesized by solvothermal reactions based on 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL). • The long-flexible ligand (HL) is a good candidate to produce interpenetrating architectures. • The secondary dicarboxylic acid ligands play important roles in the spatial connective fashions and the formation of various dimensional compounds. • The magnetism studies show that both 2 and 5 exhibit antiferromagnetic interactions.

  15. Orally efficacious novel small molecule 6-chloro-6-deoxy-1,2,3,4-tetra-O-galloyl-α-D-glucopyranose selectively and potently stimulates insulin receptor and alleviates diabetes.

    PubMed

    Cao, Yanyan; Li, Yunsheng; Kim, Jaekyung; Ren, Yulin; Himmeldirk, Klaus; Liu, Yi; Qian, Yanrong; Liu, Fengming; Chen, Xiaozhuo

    2013-01-01

    Type 2 diabetes (T2D) has become an epidemic worldwide while T1D remains a great medical challenge. Insulin receptor (IR) signaling activators could alleviate hyperglycemia, reduce the burden on the pancreas, and contribute to prevention and treatment of both types of diabetes. Previously, we reported the synthesis and identification of a natural antidiabetic compound α-penta-galloyl-glucose (α-PGG). Subsequent studies led to the identification of an α-P6GG derivative, 6-chloro-6-deoxy-1,2,3,4-tetra-O-galloyl-α-D-glucopyranose (6Cl-TGQ). Here, we report that 6Cl-TGQ not only induced rapid and long-lasting glucose uptake comparable to insulin in adipocytes but also reduced high blood glucose levels to near normal and significantly decreased plasma insulin levels and improved glucose tolerance performance in high-fat diet-induced T2D mice when administered orally at 5 mg/kg once every other day. Moreover, a single gavage of 6Cl-TGQ at 10 mg/kg induced rapid and sharp decline of blood glucose in streptozotocin-induced T1D mice. Our studies further indicated that 6Cl-TGQ activated IR signaling in cell models and insulin-responsive tissues of mice. 6Cl-TGQ-induced Akt phosphorylation was completely blocked by IR and PI3K inhibitors, while the induced glucose uptake was blocked by the same compounds and a Glut4 inhibitor. Receptor binding studies indicated that 6Cl-TGQ bound to IR with a higher affinity than α-PGG. Importantly, 6Cl-TGQ, unlike insulin, selectively induced phosphorylation of IR without activating IGF1R or its signaling and did not increase cancer cell proliferation. These results indicate that 6Cl-TGQ is a potent orally efficacious compound with low carcinogenic potential and may contribute to the prevention and treatment of T1D and T2D.

  16. Polybrominated diphenyl ether (PBDE) accumulation by earthworms (Eisenia fetida) exposed to biosolids-, polyurethane foam microparticle-, and Penta-BDE-amended soils.

    PubMed

    Gaylor, Michael O; Harvey, Ellen; Hale, Robert C

    2013-12-01

    Polybrominated diphenyl ether (PBDE) flame retardants have been used in consumer polymers at up to percent levels. While long viewed as biologically inaccessible therein, PBDEs may become bioaccessible following volatilization or polymer deterioration. PBDEs may then enter soils via polymer fragmentation or following land application of sewage sludge-derived biosolids. Studies of direct PBDE uptake from these materials by soil organisms are scarce. We thus exposed earthworms ( Eisenia fetida ) to artificial soil amended with a Class B anaerobically digested biosolid (ADB), an exceptional quality composted biosolid (CB), PBDE-containing polyurethane foam (PUF) microparticles, and Penta-BDE-spiked artificial soil (SAS). Worms accumulated mg/kg (lipid) ∑Penta-PBDE burdens from all substrates. Biota-soil accumulation factors (BSAFs) for worms exposed to ADB- and CB-amended soils were comparable after 28 d. BSAFs generally decreased with increasing congener KOW and substrate dosage. Biosolids-associated PBDE bioavailability was lower than spiked PBDEs. BSAFs for worms exposed to PUF microparticles ranged from 3.9 to 33.4, with ∑Penta-PBDE tissue burdens reaching 3740 mg/kg lipid. Congener accumulation patterns were similar in worms and polyethylene passive sampling devices immersed in ADB-amended soil coincident with exposed worms. However, passive sampler accumulation factors were lower than BSAFs. Our results demonstrate that PBDEs may accumulate in organisms ingesting soils containing biosolids or waste plastics. Such organisms may then transfer their burdens to predators or translocate them from the site of application/disposal.

  17. Polybrominated diphenyl ether (PBDE) accumulation by earthworms (Eisenia fetida) exposed to biosolids-, polyurethane foam microparticle-, and Penta-BDE-amended soils.

    PubMed

    Gaylor, Michael O; Harvey, Ellen; Hale, Robert C

    2013-12-01

    Polybrominated diphenyl ether (PBDE) flame retardants have been used in consumer polymers at up to percent levels. While long viewed as biologically inaccessible therein, PBDEs may become bioaccessible following volatilization or polymer deterioration. PBDEs may then enter soils via polymer fragmentation or following land application of sewage sludge-derived biosolids. Studies of direct PBDE uptake from these materials by soil organisms are scarce. We thus exposed earthworms ( Eisenia fetida ) to artificial soil amended with a Class B anaerobically digested biosolid (ADB), an exceptional quality composted biosolid (CB), PBDE-containing polyurethane foam (PUF) microparticles, and Penta-BDE-spiked artificial soil (SAS). Worms accumulated mg/kg (lipid) ∑Penta-PBDE burdens from all substrates. Biota-soil accumulation factors (BSAFs) for worms exposed to ADB- and CB-amended soils were comparable after 28 d. BSAFs generally decreased with increasing congener KOW and substrate dosage. Biosolids-associated PBDE bioavailability was lower than spiked PBDEs. BSAFs for worms exposed to PUF microparticles ranged from 3.9 to 33.4, with ∑Penta-PBDE tissue burdens reaching 3740 mg/kg lipid. Congener accumulation patterns were similar in worms and polyethylene passive sampling devices immersed in ADB-amended soil coincident with exposed worms. However, passive sampler accumulation factors were lower than BSAFs. Our results demonstrate that PBDEs may accumulate in organisms ingesting soils containing biosolids or waste plastics. Such organisms may then transfer their burdens to predators or translocate them from the site of application/disposal. PMID:24160918

  18. Spectroscopic evaluation of Co(II), Ni(II) and Cu(II) complexes derived from thiosemicarbazone and semicarbazone

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Kumar, Anil

    2007-12-01

    Co(II), Ni(II) and Cu(II) complexes were synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan. These complexes were characterized by elemental analysis, molar conductance, magnetic moment, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO corresponds to non-electrolytic nature. All the complexes are of high-spin type. On the basis of different spectral studies six coordinated geometry may be assigned for all the complexes except Co(L) 2(SO 4) and Cu(L) 2(SO 4) [where L = L 1 and L 2] which are of five coordinated square pyramidal geometry.

  19. (2E,25E)-11,14,17,33,36,39,42-Hepta-oxa-penta-cyclo-[41.4.0.0.0.0]hepta-tetra-conta-1(43),2,5(10),6,8,18,20,22,25,27,29,31,44,46-tetra-decaene-4,24-dione.

    PubMed

    Anh, Le Tuan; Hieu, Truong Hong; Soldatenkov, Anatoly T; Soldatova, Svetlana A; Khrustalev, Victor N

    2011-05-01

    The title compound, C(40)H(40)O(9), is a product of the double crotonic condensation of bis-(2-acetyl-phen-oxy)-3-oxapentane with bis-(2-formyl-phen-oxy)-3,6-dioxaoctane. The title macromolecule includes the 31-crown-7-ether skeletal unit and adopts a saddle-like conformation. The two ethyl-ene fragments have E configurations. The volume of the inter-nal cavity of the macrocycle is approximately 125 Å(3). In the crystal, the mol-ecules are arranged at van der Waals distances. PMID:21754440

  20. (2E,25E)-11,14,17,33,36,39,42-Hepta­oxa­penta­cyclo­[41.4.0.05,10.018,23.027,32]hepta­tetra­conta-1(43),2,5(10),6,8,18,20,22,25,27,29,31,44,46-tetra­decaene-4,24-dione

    PubMed Central

    Anh, Le Tuan; Hieu, Truong Hong; Soldatenkov, Anatoly T.; Soldatova, Svetlana A.; Khrustalev, Victor N.

    2011-01-01

    The title compound, C40H40O9, is a product of the double crotonic condensation of bis­(2-acetyl­phen­oxy)-3-oxapentane with bis­(2-formyl­phen­oxy)-3,6-dioxaoctane. The title macromolecule includes the 31-crown-7-ether skeletal unit and adopts a saddle-like conformation. The two ethyl­ene fragments have E configurations. The volume of the inter­nal cavity of the macrocycle is approximately 125 Å3. In the crystal, the mol­ecules are arranged at van der Waals distances. PMID:21754440

  1. Detection of mitochondrial COII DNA sequences in ant guts as a method for assessing termite predation by ants.

    PubMed

    Fayle, Tom M; Scholtz, Olivia; Dumbrell, Alex J; Russell, Stephen; Segar, Simon T; Eggleton, Paul

    2015-01-01

    Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest. We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII) from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2 % of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1 % of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63 % (5/7; Camponotus sp. 1) to 0 % (0/7; Ponera sp. 1), there was no evidence (with small sample sizes) for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that ant-termite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs. PMID:25853549

  2. Detection of Mitochondrial COII DNA Sequences in Ant Guts as a Method for Assessing Termite Predation by Ants

    PubMed Central

    Fayle, Tom M.; Scholtz, Olivia; Dumbrell, Alex J.; Russell, Stephen; Segar, Simon T.; Eggleton, Paul

    2015-01-01

    Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest. We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII) from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2 % of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1 % of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63 % (5/7; Camponotus sp. 1) to 0 % (0/7; Ponera sp. 1), there was no evidence (with small sample sizes) for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that ant-termite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs. PMID:25853549

  3. Detection of mitochondrial COII DNA sequences in ant guts as a method for assessing termite predation by ants.

    PubMed

    Fayle, Tom M; Scholtz, Olivia; Dumbrell, Alex J; Russell, Stephen; Segar, Simon T; Eggleton, Paul

    2015-01-01

    Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest. We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII) from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2 % of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1 % of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63 % (5/7; Camponotus sp. 1) to 0 % (0/7; Ponera sp. 1), there was no evidence (with small sample sizes) for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that ant-termite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs.

  4. Insulin receptor signaling activated by penta-O-galloyl-α-D: -glucopyranose induces p53 and apoptosis in cancer cells.

    PubMed

    Cao, Yanyan; Evans, Susan C; Soans, Eroica; Malki, Ahmed; Liu, Yi; Liu, Yan; Chen, Xiaozhuo

    2011-09-01

    p53 is essential for cell cycle arrest and apoptosis induction while insulin receptor (IR) signaling is important for cell metabolism and proliferation and found upregulated in cancers. While IR has recently been found to be involved in apoptosis, p53 induction or apoptosis mediated through IR signaling activation has never been documented. Here, we report that the IR signaling pathway, particularly the IR-MEK pathway, mediates biological and biochemical changes in p53 and apoptosis in tumor cells. Specifically, natural compound penta-O-galloyl-α-D: -glucopyranose (α-PGG), a previously characterized IR signaling activator, induced apoptosis in RKO cells without significantly affecting its normal counterpart FHC cells. α-PGG induced apoptosis in RKO cells through p53, Bax and caspase 3. Importantly, α-PGG's ability to elevate p53 was diminished by IR inhibitor and IR-siRNA, suggesting a non-conventional role of IR as being involved in p53 induction. Further studies revealed that α-PGG activated MEK, a downstream signaling factor of IR. Blocking MEK significantly suppressed α-PGG-induced p53 and Bax elevation. All these results suggested that α-PGG induced p53, Bax, and apoptosis through the IR-MEK signaling pathway. The unique activity of α-PGG, a novel IR phosphorylation and apoptosis inducer, may offer a new therapeutic strategy for eliciting apoptotic signal and inhibiting cancer growth.

  5. Anti-cancer, anti-diabetic and other pharmacologic and biological activities of penta-galloyl-glucose

    PubMed Central

    Zhang, Jinhui; Li, Li; Kim, Sung-Hoon; Hagerman, Ann E.; Lü, Junxuan

    2010-01-01

    1, 2, 3, 4, 6-penta-O-galloyl-β-D-glucose (PGG) is a polyphenolic compound highly enriched in a number of medicinal herbals. Several in vitro and a handful of in vivo studies have shown that PGG exhibits multiple biological activities which implicate a great potential for PGG in the therapy and prevention of several major diseases including cancer and diabetes. Chemically and functionally, PGG appears to be distinct from its constituent gallic acid or tea polyphenols. For anti-cancer activity, three published in vivo preclinical cancer model studies with PGG support promising efficacy to selectively inhibit malignancy without host toxicity. Potential mechanisms include anti-angiogenesis, anti-proliferative actions through inhibition of DNA replicative synthesis and S-phase arrest and also G1 arrest, induction of apoptosis, anti-inflammation and anti-oxidation. Putative molecular targets include p53, Stat3, Cox-2, VEGFR1, AP-1, SP-1, Nrf-2 and MMP-9. For anti-diabetic activity, PGG and analogues appear to improve glucose uptake. However, very little is known about the absorption, pharmacokinetics and metabolism of PGG, nor its toxicity profile. The lack of large quantity of highly pure PGG has been a bottleneck limiting in vivo validation of cancer preventive and therapeutic efficacies in clinically relevant models. PMID:19575286

  6. 40 CFR 721.5225 - Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl) (specific name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Naphthalene,1,2,3,4-tetra- hy-dro(1... New Uses for Specific Chemical Substances § 721.5225 Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl... substance naphthalene,1,2,3,4-tetrahydro(1-phenylethyl) (PMN P-85-1331) is subject to reporting under...

  7. 40 CFR 721.5225 - Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl) (specific name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Naphthalene,1,2,3,4-tetra- hy-dro(1... New Uses for Specific Chemical Substances § 721.5225 Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl... substance naphthalene,1,2,3,4-tetrahydro(1-phenylethyl) (PMN P-85-1331) is subject to reporting under...

  8. 40 CFR 721.5225 - Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl) (specific name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Naphthalene,1,2,3,4-tetra- hy-dro(1... New Uses for Specific Chemical Substances § 721.5225 Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl... substance naphthalene,1,2,3,4-tetrahydro(1-phenylethyl) (PMN P-85-1331) is subject to reporting under...

  9. 40 CFR 721.5225 - Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl) (specific name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Naphthalene,1,2,3,4-tetra- hy-dro(1... New Uses for Specific Chemical Substances § 721.5225 Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl... substance naphthalene,1,2,3,4-tetrahydro(1-phenylethyl) (PMN P-85-1331) is subject to reporting under...

  10. 40 CFR 721.5225 - Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl) (specific name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Naphthalene,1,2,3,4-tetra- hy-dro(1... New Uses for Specific Chemical Substances § 721.5225 Naphthalene,1,2,3,4-tetra- hy-dro(1-phenylethyl... substance naphthalene,1,2,3,4-tetrahydro(1-phenylethyl) (PMN P-85-1331) is subject to reporting under...

  11. G4-Tetra DNA Duplex Induce Lung Cancer Cell Apoptosis in A549 Cells

    NASA Astrophysics Data System (ADS)

    Xu, Xiaobo; Zhao, YiZhuo; Lu, Hu; Fu, Cuiping; Li, Xiao; Jiang, Liyan; Li, Shanqun

    2016-10-01

    The specific DNA is typically impermeable to the plasma membrane due to its natural characters, but DNA tetra structures (DTNs) can be readily uptake by cells in the absence of transfection agents, providing a new strategy to deliver DNA drugs. In this research, the delivery efficiency of tetrahedral DNA nanostructures was measured on adenocarcinomic human alveolar basal epithelial (A549) cells via delivering AS1411 (G4). The DNA tetra-AS1411 complex was rapidly and abundantly uptake by A549 cells, and the induced apoptosis was enhanced. Furthermore, biodistribution in mouse proved the rapid clearance from non-targeted organs in vivo. This study improved the understanding of potential function in DNA-based drug delivery and proved that DTNs-AS1411 could be potentially useful for the treatment of lung cancer.

  12. 2,2,6,6-Tetra­methyl­piperidinium triisopropoxysilanethiol­ate

    PubMed Central

    Baranowska, Katarzyna; Roman, Paweł; Socha, Justyna

    2009-01-01

    The crystal of the title compound, C9H20N+·C9H21O3SSi−, is built of aggregates, each made up of two 2,2,6,6-tetra­methyl­piperidinium cations and two triisopropoxysilanethiol­ate anions. The aggregates are linked by four N—H⋯S bonds and correspond to an R 2 4(8) graph-set motif. PMID:21578416

  13. 3-Phenyl­tetra­hydro­furan-2,5-dione

    PubMed Central

    Quan, Li; Yin, Handong

    2009-01-01

    In the title compound, C10H8O3, the dihedral angle between the approximately planar tetra­hydro­furan-2,5-dione ring [maximum deviation 0.014 (3) Å] and the phenyl ring is 85.68 (8)°. Weak C—H⋯O=C inter­molecular hydrogen-bonding contacts are observed in the structure. PMID:21581623

  14. N-(5-Amino-1H-tetra­zol-1-yl)formamide

    PubMed Central

    He, Chun-Lin; Du, Zhi-Ming; Tang, Zheng-Qiang; Cong, Xiao-Min; Meng, Ling-Qiao

    2009-01-01

    In the title compound, C2H4N6O, the planar [maximum deviation = 0.006 (2) Å] amino­tetra­zole group makes a dihedral angle of 83.65 (8)° with the formamide unit. In the crystal structure, inter­molecular N—H⋯N, N—H⋯O and C—H⋯N hydrogen bonds are responsible for the formation of a three-dimensional network. PMID:21578483

  15. Di-μ-hydroxido-bis-[hemiaqua-(N,N,N',N'-tetra-methyl-ethane-1,2-diamine)-copper(II)] bis-(tetra-fluoridoborate).

    PubMed

    Haníková, Jaroslava; Kuchár, Juraj; Trávníček, Zdeněk; Cernák, Juraj

    2012-06-01

    The title compound, [Cu(2)(OH)(2)(C(6)H(16)N(2))(2)(H(2)O)](BF(4))(2), consists of dinuclear centrosymmetric [Cu(2)(OH)(2)(tmen)(2)(H(2)O)](2+) complex cations (tmen = N,N,N',N'-tetra-methyl-ethane-1,2-diamine) and tetra-fluoridoborate anions. In the cation, the Cu(II) atom shows a slightly distorted square-pyramidal coordination geometry provided by a pair of μ-OH(-) anions and by the N atoms of a chelate tmen ligand in the basal plane. The apical position is statistically occupied by the O atom of a half-occupancy water mol-ecule. The F atoms of the anion are disordered over three sets of sites with occupancies of 0.598 (9):0.269 (6):0.134 (8). The crystal packing is governed by ionic forces as well as by O-H⋯F hydrogen bonds. PMID:22719335

  16. Guidelines for the tetra-primer ARMS-PCR technique development.

    PubMed

    Medrano, Ruan Felipe Vieira; de Oliveira, Camila Andréa

    2014-07-01

    The tetra-primer amplification refractory mutation system-polymerase chain (ARMS-PCR) reaction is a simple and economical method to genotype single-nucleotide polymorphisms (SNPs). It uses four primers in a single PCR and is followed just by gel electrophoresis. However, the optimization step can be very hardworking and time-consuming. Hence, we propose to demonstrate and discuss critical steps for its development, in a way to provide useful information. Two SNPs that provided different amplification conditions were selected. DNA extraction methods, annealing temperatures, PCR cycles protocols, reagents, and primers concentration were also analyzed. The use of tetra-primer ARMS-PCR could be impaired for SNPs in DNA regions rich in cytosine and guanine and for samples with DNA not purified. The melting temperature was considered the factor of greater interference. However, small changes in the reagents concentration significantly affect the PCR, especially MgCl2. Balancing the inner primers band is also a key step. So, in order to balance the inner primers band, intensity is important to observe which one has the weakest band and promote its band by increasing its concentration. The use of tetra-primer ARMS-PCR attends the expectations of modern genomic research and allows the study of SNPs in a fast, reliable, and low-cost way. PMID:24519268

  17. Assessment of specific energy absorption rate (SAR) in the head from a TETRA handset

    NASA Astrophysics Data System (ADS)

    Dimbylow, Peter; Khalid, Mohammed; Mann, Simon

    2003-12-01

    Finite-difference time-domain (FDTD) calculations of the specific energy absorption rate (SAR) from a representative TETRA handset have been performed in an anatomically realistic model of the head. TETRA (Terrestrial Trunked Radio) is a modern digital private mobile radio system designed to meet the requirements of professional users, such as the police and fire brigade. The current frequency allocations in the UK are 380-385 MHz and 390-395 MHz for the public sector network. A comprehensive set of calculations of SAR in the head was performed for positions of the handset in front of the face and at both sides of the head. The representative TETRA handset considered, operating at 1 W in normal use, will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a monopole antenna operating at 3 W in normal use will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a helical antenna operating at 3 W in normal use will show compliance with the ICNIRP occupational exposure restriction but will be over the public exposure restriction by up to ~50% if kept in the position of maximum SAR for 6 min continuously.

  18. Assessment of specific energy absorption rate (SAR) in the head from a TETRA handset.

    PubMed

    Dimbylow, Peter; Khalid, Mohammed; Mann, Simon

    2003-12-01

    Finite-difference time-domain (FDTD) calculations of the specific energy absorption rate (SAR) from a representative TETRA handset have been performed in an anatomically realistic model of the head. TETRA (Terrestrial Trunked Radio) is a modern digital private mobile radio system designed to meet the requirements of professional users, such as the police and fire brigade. The current frequency allocations in the UK are 380-385 MHz and 390-395 MHz for the public sector network. A comprehensive set of calculations of SAR in the head was performed for positions of the handset in front of the face and at both sides of the head. The representative TETRA handset considered. operating at 1 W in normal use, will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a monopole antenna operating at 3 W in normal use will show compliance with both the ICNIRP occupational and public exposure restrictions. The handset with a helical antenna operating at 3 W in normal use will show compliance with the ICNIRP occupational exposure restriction but will be over the public exposure restriction by up to approximately 50% if kept in the position of maximum SAR for 6 min continuously.

  19. Enhanced NH3-Sensitivity of Reduced Graphene Oxide Modified by Tetra-α-Iso-Pentyloxymetallophthalocyanine Derivatives.

    PubMed

    Li, Xiaocheng; Wang, Bin; Wang, Xiaolin; Zhou, Xiaoqing; Chen, Zhimin; He, Chunying; Yu, Zheying; Wu, Yiqun

    2015-12-01

    Three kinds of novel hybrid materials were prepared by noncovalent functionalized reduced graphene oxide (rGO) with tetra-α-iso-pentyloxyphthalocyanine copper (CuPc), tetra-α-iso-pentyloxyphthalocyanine nickel (NiPc) and tetra-α-iso-pentyloxyphthalocyanine lead (PbPc) and characterized by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), Raman spectra, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and atomic force microscope (AFM). The as-synthesized MPc/rGO hybrids show excellent NH3 gas-sensing performance with high response value and fast recovery time compared with bare rGO. The enhancement of the sensing response is mainly attributed to the synergism of gas adsorption of MPc to NH3 gas and conducting network of rGO with greater electron transfer efficiency. Strategies for combining the good properties of rGO and MPc derivatives will open new opportunities for preparing and designing highly efficient rGO chemiresistive gas-sensing hybrid materials for potential applications in gas sensor field. PMID:26403926

  20. Enhanced NH3-Sensitivity of Reduced Graphene Oxide Modified by Tetra-α-Iso-Pentyloxymetallophthalocyanine Derivatives

    NASA Astrophysics Data System (ADS)

    Li, Xiaocheng; Wang, Bin; Wang, Xiaolin; Zhou, Xiaoqing; Chen, Zhimin; He, Chunying; Yu, Zheying; Wu, Yiqun

    2015-09-01

    Three kinds of novel hybrid materials were prepared by noncovalent functionalized reduced graphene oxide (rGO) with tetra-α-iso-pentyloxyphthalocyanine copper (CuPc), tetra-α-iso-pentyloxyphthalocyanine nickel (NiPc) and tetra-α-iso-pentyloxyphthalocyanine lead (PbPc) and characterized by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), Raman spectra, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and atomic force microscope (AFM). The as-synthesized MPc/rGO hybrids show excellent NH3 gas-sensing performance with high response value and fast recovery time compared with bare rGO. The enhancement of the sensing response is mainly attributed to the synergism of gas adsorption of MPc to NH3 gas and conducting network of rGO with greater electron transfer efficiency. Strategies for combining the good properties of rGO and MPc derivatives will open new opportunities for preparing and designing highly efficient rGO chemiresistive gas-sensing hybrid materials for potential applications in gas sensor field.

  1. Semiconducting behavior of substituted tetra-azaporphyrin thin films in photoelectrochemical cells

    SciTech Connect

    Yanagi, H.; Tsukatani, K.; Yamaguchi, H.; Ashida, M. . Faculty of Engineering); Schlettwein, D.; Woehrle, D. . Organische und Makromolekulare Chemie)

    1993-07-01

    Phthalocyanines are well-known organic semiconductors and have attracted interest in application to electrophotography, chemical sensors, and solar energy conversion. Photoelectrochemical properties of zinc(II) and copper(II) complexes of (1) phthalocyanine, (2) tetrapyrido [2,3-b;2[prime],3[prime]-g;2[double prime],3[double prime]-1;2[prime][double prime],3[prime][double prime]-q]-5,10,15,20-tetra-azaporphyrin, and (3) tetrapyrazino[b;g;1;q]-5,10,15,20-tetra-azaporphyrin, were investigated in thin-film electrodes prepared by vacuum deposition (VD), drop-casting (DC) and in situ synthesis (IS). The opposing behavior, photoreduction at electrodes of 1 and photo-oxidation at electrodes of 2 and 3, are discussed in terms of a band-energy shift of tetra-azaporphyrin macrocycles caused by substitution with heterocyclic pyrido and pyrazino groups. The photoelectrochemical efficiency of the electrodes is strongly affected by the film morphology which is dependent on the preparation methods, and increased in order of DC

  2. A new coordination tetra­mer of copper(I) iodide and benzyl­dimethyl­amine: tetra-μ3-iodido-tetra­kis[(benzyl­dimethyl­amine-κN)copper(I)

    PubMed Central

    Yang, Shuying; Li, Yuebao; Cui, Yujie; Pan, Jianguo

    2009-01-01

    The title compound, [Cu4I4(C9H13N)4], has a distorted cubane-like [Cu4I4] core structure. Each CuI atom is tetra­hedrally coordinated by three I atoms and one N atom of an benzyl­dimethyl­amine ligand. Each I atom acts as a μ3-ligand, linking three CuI atoms. The Cu—I bond distances vary between 2.6328 (7) and 2.7121 (6) Å, while the Cu—N bond distances vary between 2.107 (3) and 2.122 (3) Å. PMID:21583366

  3. Anti-cancer gallotannin penta-O-galloyl-beta-D-glucose is a nanomolar inhibitor of select mammalian DNA polymerases.

    PubMed

    Mizushina, Yoshiyuki; Zhang, Jinhui; Pugliese, Angelo; Kim, Sung-Hoon; Lü, Junxuan

    2010-10-15

    Penta-1,2,3,4,6-O-galloyl-beta-D-glucose (PGG) has been shown by us and others to inhibit the in vivo growth of human prostate cancer (PCa) xenografts in athymic nude mice and mouse lung cancer allograft in syngenic mice without evident adverse effect on their body weight. We observed a rapid inhibition of DNA synthesis in S-phase cells in PGG-exposed cancer cells and in PGG-treated isolated nuclei. The purpose of the present study was to test the hypothesis that PGG inhibits DNA replicative synthesis through a direct inhibition of one or more DNA polymerases (pols). Using purified pols, we show that PGG exhibited a selective inhibition against the activities of B-family replicative pols (alpha, delta and epsilon) and Y-family (eta, iota and kappa) of bypass synthesis pols, and the inhibitory effect of PGG on pol alpha was the strongest with IC(50) value of 13 nM. PGG also inhibited pol beta, but the potency was an order of magnitude less than against pol alpha. PGG inhibition of pol alpha and kappa activity was non-competitive with respect to the DNA template-primer and the dNTP substrate; whereas it inhibited pol beta competitively. Docking simulation on pol beta, which is the only mammalian pol with solved crystal structure, suggests several favorable interactions with the catalytic pocket/binding site for the incoming dNTP. These results support PGG as a novel inhibitor of select families of mammalian pols by distinct mechanisms, and suggest that the potent pol inhibition may contribute to its anti-cancer efficacy.

  4. Biotransformation Capacity of Carboxylesterase in Skin and Keratinocytes for the Penta-Ethyl Ester Prodrug of DTPA.

    PubMed

    Fu, Jing; Sadgrove, Matthew; Marson, Lesley; Jay, Michael

    2016-08-01

    The penta-ethyl ester prodrug of the chelating agent diethylene triamine pentaacetic acid (DTPA), referred to as C2E5, effectively accelerated clearance of americium after transdermal delivery. Carboxylesterases (CESs) play important roles in facilitating C2E5 hydrolysis. However, whether CESs in human skin hydrolyze C2E5 remains unknown. We evaluated the gene and protein expression of CESs in distinctive human epidermal cell lines: HEKa, HEKn, HaCaT, and A431. The substrates p-nitrophenyl acetate (pNPA) and 4-nitrophenyl valerate (4-NPV) were used to access esterase and CES activity. C2E5 hydrolysis was measured by radiometric high-performance liquid chromatography after incubation of [(14)C]C2E5 with supernatant fractions after centrifugation at 9000g (S9) prepared from skin cell lines. CES-specific inhibitors were used to access metabolism in human skin S9 fractions with analysis by liquid chromatography-tandem mass spectrometry. We identified the human carboxylesterase 1 and 2 (CES1 and CES2) bands in a Western blot. The gene expression of these enzymes was supported by a real-time polymerase chain reaction (qPCR). pNPA and 4-NPV assays demonstrated esterase and CES activity in all the cell lines that were comparable to human skin S9 fractions. The prodrug C2E5 was hydrolyzed by skin S9 fractions, resulting in a primary metabolite, C2E4. In human skin S9 fractions, inhibition of C2E5 hydrolysis was greatest with a pan-CES inhibitor (benzil). CES1 inhibition (troglitazone) was greater than CES2 (loperamide), suggesting a primary metabolic role for CES1. These results indicate that human keratinocyte cell lines are useful for the evaluation of human cutaneous metabolism and absorption of ester-based prodrugs. However, keratinocytes from skin provide a small contribution to the overall metabolism of C2E5. PMID:27130352

  5. Complex Formation in a Liquid-Liquid Extraction System Containing Co(II), 4-(2-Thiazolylazo)resorcinol and Monotetrazolium Salt.

    PubMed

    Divarova, Vidka; Stojnova, Kirila; Racheva, Petya; Lekova, Vanya

    2016-01-01

    The ion-associated complex formed between anionic chelate of Co(II)-4-(2-Thiazolylazo)resorcinol (TAR) with the monotetrazolium cation of 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-phenyl-2H-tetrazolium chloride (INT) in the liquid-liquid extraction system Co(II)-TAR-INT-H(2)O-CHCl(3) was studied by the spectrophotometric method. The optimum extraction conditions of Co(II) were found. The extraction equilibria were studied. The equilibrium constants, the recovery factor and some analytical characteristics were calculated. The validity of Beer's law was checked. The molar ratio of the components in the ternary ion-associated complex Co(II)-TAR-INT was determined. The general formula of the complex was suggested. The effect of various foreign ions and reagents on the process of complex formation in the liquid-liquid extraction system was studied.

  6. Spectroscopic investigation of the structure of complex compounds of Cu(II), Co(II), and Ni(II) with. cap alpha. - and. beta. -diketone

    SciTech Connect

    Krymova, N.M.; Ivanov, V.E.; Ostapkevich, N.A.

    1986-11-10

    In the reactions of Cu(II), Co(II), and Ni(II) chlorides with 2,3-butanedione and 2,4-pentanedione isonicotinoylhydrazones in neutral and weakly acid media complex compounds of the addition-product type are formed, but in an alkaline medium inner-complex compounds are formed. By methods of electronic and ESR spectroscopy it was shown that the Cu(II) complex compounds have a planar-square structure, the Ni(II) complexes are octrahedral, but the Co(II) complexes have a tetrahedral or distorted tetrahedral structure. In the spectrochemical series 2,3-butanedione and 2,4-pentanedione isonicotinoylhydrazones occupy positions between water and ammonia.

  7. Spectral studies on Co(II), Ni(II) and Cu(II) complexes with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Kumar, Anil

    2007-04-01

    Co(II), Ni(II) and Cu(II) complexes are synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan. These complexes are characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurements of the complexes in DMSO correspond to non-electrolytic nature except Ni(L) 2(NO 3) 2, which is 1:2 electrolyte. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry may be assigned for Co(II) and Ni(II) complexes except nitrato complexes of Ni(II) which is of tetrahedral geometry, whereas tetragonal geometry for Cu(II) complexes.

  8. Wet oxidative method for removal of 2,4,6-trichlorophenol in water using Fe(III), Co(II), Ni(II) supported MCM41 catalysts.

    PubMed

    Chaliha, Suranjana; Bhattacharyya, Krishna Gopal

    2008-02-11

    Chlorophenols in water are resistant to biological oxidation and they have to be destroyed by chemical oxidation. In the present work, Fe(III), Co(II) and Ni(II) incorporated MCM41 mesoporous solids were used as catalysts for oxidation of 2,4,6-trichlorophenol in water with or without the oxidant, H(2)O(2). The catalysts were prepared by impregnation and were characterized by XRD and FTIR measurements. The parent MCM41, Fe(III), Co(II) and Ni(II) impregnated MCM41 had cation exchange capacity of 20.5, 25.5, 24.2, 26.0 mequiv./100g, respectively. The catalysts were used after calcination at 773-873 K for 5 h. The reactions were carried out in a high pressure stirred reactor at 0.2 MPa (autogenous) and 353 K under various reaction conditions. The conversion achieved with Fe(III), Co(II) and Ni(II) incorporated MCM41 in 5h is respectively 59.4, 50.0 and 65.6% with 2,4,6-TCP:H(2)O(2) molar ratio of 1:1, and 60.2, 60.9 and 68.8% in absence of H(2)O(2). The oxidation has a first order rate coefficient of (1.2-4.8)x10(-3)min(-1). The results show that introduction of Fe(III), Co(II) and Ni(II) into MCM-41 through impregnation produces very effective catalysts for wet oxidation of 2,4,6-trichlorophenol.

  9. Characterization and biological studies on Co(II), Ni(II) and Cu(II) complexes of carbohydrazones ending by pyridyl ring

    NASA Astrophysics Data System (ADS)

    Abu El-Reash, G. M.; El-Gammal, O. A.; Ghazy, S. E.; Radwan, A. H.

    2013-03-01

    The chelating behavior of ligands based on carbohydrazone core modified with pyridine end towards Co(II), Ni(II) and Cu(II) ions have been examined. The ligands derived from the condensation of carbohydrazide with 2-acetylpyridine (H2APC) and 4-acetylpyridine (H2APEC). The 1H NMR, IR data and the binding energy calculations of H2APC revealed the presence of two stereoisomers syn and anti in the solid state and in the solution. The 1H NMR, IR data and the binding energy calculations confirmed the presence of H2APEC in one keto form only in the solid state and in the solution. The spectroscopic data confirmed that H2APC behaves as a monobasic pentadentate in Co(II) and Cu(II) complexes and as mononegative tetradentate in Ni(II) complex. On the other hand, H2APEC acts as a mononegative tridentate in Co(II) complex, neutral tridentate in Ni(II) complex and neutral bidentate in Cu(II) complex. The electronic spectra and the magnetic measurements of complexes as well as the ESR of the copper complexes suggested the octahedral geometry. The bond length and bond angles were evaluated by DFT method using material studio program. The thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. The antioxidant (DDPH and ABTS methods), anti-hemolytic and in vitro Ehrlich ascites of the compounds have been screened.

  10. Application of carrier element free coprecipitation (CEFC) method for determination of Co(II), Cu(II) and Ni(II) ions in food and water samples.

    PubMed

    Serencam, Huseyin; Duran, Celal; Ozdes, Duygu; Bektas, Hakan

    2013-01-01

    A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element free coprecipitation (CEFC) of Co(II), Cu(II), and Ni(II) ions by using 2-{4-[2-(1H-indol-3-yl)ethyl]-3-(4-methylbenzyl)-5-oxo-4,5-dihydro- 1H-1,2,4-triazol-l-yl}-N'-(pyridin-2-yl methylidene)acetohydrazide (IMOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry (FAAS). The detection limits for Co(II), Cu(II) and Ni(II) ions were found to be 0.40, 0.16 and 0.17 microg L(-1), respectively, and the relative standard deviations for the analyte ions were lower than 3.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Co(II), Cu(II) and Ni(II) ions levels in sea and stream water as liquid samples and red pepper, black pepper, and peppermint as solid samples. PMID:23878931

  11. Preconcentration of Cu(II), Co(II), and Ni(II) using an Optimized Enrichment Procedure: Useful and Alternative Methodology for Flame Atomic Absorption Spectrometry.

    PubMed

    Tokay, Feyzullah; Bağdat, Sema

    2016-03-01

    In this paper, a new solid phase extraction procedure is described for Cu(II), Co(II), and Ni(II). Silica gel which was coated with N,N'-bis(4-methoxysalicylidene) ethylenediamine (MSE) is used as a sorbent. Three independent variables were optimized using central composite design (CCD) for sorption and elution of metal ions. The optimum values of sorption and elution variables allowed simultaneous preconcentration of the ions in same conditions as follows, for sorption, pH 6.9, flow rate 5.4 mL min(-1), sample volume 50.0 mL, and for elution, flow rate 2.6 mL min(-1), eluent concentration 1.0 mol L(-1), eluent volume 5.0 mL. The detection limits (LOD) were found to be 1.1 µg L(-1) for Cu(II), 7.4 µg L(-1) for Co(II), and 7.5 µg L(-1) for Ni(II) and preconcentration factor was 200 for each of the ions. The accuracy of the method was tested with Lake Ontario water and multi-element standard solution. The proposed method was also applied to various water samples. The proposed method can be alternatively suggested as accurate, precise, easy, and a cheap method for Cu(II), Co(II), and Ni(II) determination. PMID:26823544

  12. Positional isomeric tunable two Co(II) 6-connected 3-D frameworks with pentanuclear to binuclear units: structures, ion-exchange and magnetic properties.

    PubMed

    Han, Min-Le; Duan, Ya-Ping; Li, Dong-Sheng; Wang, Hai-Bin; Zhao, Jun; Wang, Yao-Yu

    2014-11-01

    Two new Co(II) based metal-organic frameworks, namely {[Co5(μ3-OH)2(m-pda)3(bix)4]·2ClO4}n (1) and {[Co2(p-pda)2(bix)2(H2O)]·H2O}n (2), were prepared by hydrothermal reactions of Co(II) salt with two isomeric dicarboxyl tectons 1,3-phenylenediacetic acid (m-pda) and 1,4-phenylenediacetic acid (p-pda), along with 1,3-bis(imidazol-L-ylmethyl)benzene (bix). Both complexes 1 and 2 have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). 1 shows a 6-connected 3-D pcu cationic framework with pentanuclear [Co5(μ3-OH)2(COO)6(bix)2](2+) units, while 2 exhibits a 6-connected 3-D msw net based on [Co2(μ2-H2O)(COO)2](2+) clusters. The results indicate that the different dispositions of the carboxylic groups of dicarboxylates have an important effect on the overall coordination frameworks. Perchlorate anions in 1 can be partly exchanged by thiocyanate and azide anions, however they are unavailable to nitrate anions. Magnetic susceptibility measurements indicate that both 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions. PMID:25190003

  13. Butterfly-like enantiomerically homochiral {Co(II)6Co(III)4} clusters exhibiting both slow magnetic relaxation and ferroelectric property.

    PubMed

    Li, Qipeng; Qian, Jinjie; Tian, Chongbin; Lin, Ping; He, Zhangzhen; Wang, Ning; Shen, Jinni; Zhang, Huabin; Chu, Tao; Yuan, Daqiang; Yang, Yi; Xue, Liping; Du, Shaowu

    2014-02-28

    A pair of enantiomerically homochiral {Co(II)6Co(III)4} clusters featuring a butterfly-like structure, [Co(II)6Co(III)4(μ3-OH)(μ3-X)(S-pa)4(pdm)6(pdmH)2](ClO4)4·3.5H2O (S-1) and [Co(II)6Co(III)4(μ3-OH)(μ3-X)(R-pa)4(pdm)6(pdmH)2](ClO4)4·3.5H2O (R-1) (X = OH or OMe, S- or R-paH = S- or R-phenylalaninol and pdmH2 = pyridine-2,6-diyldimethanol), have been synthesized and structurally characterized. They are the second largest homochiral Co clusters constructed by chiral ligands. They are also the first example of high-nuclearity homochiral Co clusters having both slow magnetic relaxation behaviour and ferroelectric property. PMID:24356559

  14. Bruceolline D: 3,3-dimethyl-1H,4H-cyclo­penta­[b]indol-2(3H)-one

    PubMed Central

    Lopchuk, Justin M.; Gribble, Gordon W.; Jasinski, Jerry P.

    2013-01-01

    The title compound, C13H13NO, crystallizes with four independent mol­ecules in the asymmetric unit. The 12-membered penta­[b]indole rings are essentially planar, with maximum deviations ranging from 0.034 (4) to 0.036 (4) Å in the four unique mol­ecules. In the crystal, weak C—H⋯O inter­actions are observed, which link the mol­ecules into chains along [010]. PMID:24046619

  15. The precursor form of Hansenula polymorpha copper amine oxidase 1 in complex with CuI and CoII

    PubMed Central

    Klema, Valerie J.; Johnson, Bryan J.; Klinman, Judith P.; Wilmot, Carrie M.

    2012-01-01

    Copper amine oxidases (CAOs) catalyze the oxidative deamination of primary amines to their corresponding aldehydes, with the concomitant reduction of O2 to H2O2. Catalysis requires two cofactors: a mononuclear copper center and the cofactor 2,4,5-trihydroxyphenylalanine quinone (TPQ). TPQ is synthesized through the post-translational modification of an endogenous tyrosine residue and requires only oxygen and copper to proceed. TPQ biogenesis in CAO can be supported by alternate metals, albeit at decreased rates. A variety of factors are thought to contribute to the degree to which a metal can support TPQ biogenesis, including Lewis acidity, redox potential and electrostatic stabilization capability. The crystal structure has been solved of one of two characterized CAOs from the yeast Hansenula polymorpha (HPAO-1) in its metal-free (apo) form, which contains an unmodified precursor tyrosine residue instead of fully processed TPQ (HPAO-1 was denoted HPAO in the literature prior to 2010). Structures of apoHPAO-1 in complex with CuI and CoII have also been solved, providing structural insight into metal binding prior to biogenesis. PMID:22691777

  16. Sensitive spectrophotometric determination of Co(II) using dispersive liquid-liquid micro-extraction method in soil samples.

    PubMed

    Hasanpour, Foroozan; Hadadzadeh, Hassan; Taei, Masoumeh; Nekouei, Mohsen; Mozafari, Elmira

    2016-05-01

    Analytical performance of conventional spectrophotometer was developed by coupling of effective dispersive liquid-liquid micro-extraction method with spectrophotometric determination for ultra-trace determination of cobalt. The method was based on the formation of Co(II)-alpha-benzoin oxime complex and its extraction using a dispersive liquid-liquid micro-extraction technique. During the present work, several important variables such as pH, ligand concentration, amount and type of dispersive, and extracting solvent were optimized. It was found that the crucial factor for the Co(II)-alpha benzoin oxime complex formation is the pH of the alkaline alcoholic medium. Under the optimized condition, the calibration graph was linear in the ranges of 1.0-110 μg L(-1) with the detection limit (S/N = 3) of 0.5 μg L(-1). The preconcentration operation of 25 mL of sample gave enhancement factor of 75. The proposed method was applied for determination of Co(II) in soil samples. PMID:27040110

  17. Co(II) and Cd(II) Complexes Derived from Heterocyclic Schiff-Bases: Synthesis, Structural Characterisation, and Biological Activity

    PubMed Central

    Ahmed, Riyadh M.; Yousif, Enaam I.; Al-Jeboori, Mohamad J.

    2013-01-01

    New monomeric cobalt and cadmium complexes with Schiff-bases, namely, N′-[(E)-(3-hydroxy-4-methoxyphenyl)methylidene]furan-2-carbohydrazide (L1) and N′-[(E)-(3-hydroxy-4-methoxyphenyl)methylidene]thiophene-2-carbohydrazide (L2) are reported. Schiff-base ligands L1 and L2 were derived from condensation of 3-hydroxy-4-methoxybenzaldehyde (iso-vanillin) with furan-2-carboxylic acid hydrazide and thiophene-2-carboxylic acid hydrazide, respectively. Complexes of the general formula [M(L)2]Cl2 (where M = Co(II) or Cd(II), L = L1 or L2) have been obtained from the reaction of the corresponding metal chloride with the ligands. The ligands and their metal complexes were characterised by spectroscopic methods (FTIR, UV-Vis, 1H, and 13C NMR spectra), elemental analysis, metal content, magnetic measurement, and conductance. These studies revealed the formation of four-coordinate complexes in which the geometry about metal ion is tetrahedral. Biological activity of the ligands and their metal complexes against gram positive bacterial strain Bacillus (G+) and gram negative bacteria Pseudomonas (G−) revealed that the metal complexes become less resistive to the microbial activities as compared to the free ligands. PMID:24027449

  18. Sensitive spectrophotometric determination of Co(II) using dispersive liquid-liquid micro-extraction method in soil samples.

    PubMed

    Hasanpour, Foroozan; Hadadzadeh, Hassan; Taei, Masoumeh; Nekouei, Mohsen; Mozafari, Elmira

    2016-05-01

    Analytical performance of conventional spectrophotometer was developed by coupling of effective dispersive liquid-liquid micro-extraction method with spectrophotometric determination for ultra-trace determination of cobalt. The method was based on the formation of Co(II)-alpha-benzoin oxime complex and its extraction using a dispersive liquid-liquid micro-extraction technique. During the present work, several important variables such as pH, ligand concentration, amount and type of dispersive, and extracting solvent were optimized. It was found that the crucial factor for the Co(II)-alpha benzoin oxime complex formation is the pH of the alkaline alcoholic medium. Under the optimized condition, the calibration graph was linear in the ranges of 1.0-110 μg L(-1) with the detection limit (S/N = 3) of 0.5 μg L(-1). The preconcentration operation of 25 mL of sample gave enhancement factor of 75. The proposed method was applied for determination of Co(II) in soil samples.

  19. Poly[[tetra­aquatetrakis­[μ3-5-(pyridine-4-carboxamido)­isophthalato]cobalt(II)digadolinium(III)] tetra­hydrate

    PubMed Central

    Deng, Yi-Fang; Chen, Man-Sheng; Zhang, Chun-Hua; Kuang, Dai-Zhi

    2011-01-01

    In the centrosymmetric polymeric title compound, {[CoGd2(C14H8N2O5)4(H2O)4]·4H2O}n, the GdIII cation is coordinated by one water mol­ecule and four pyridine-4-carboxamido­isophthalate (L) anions in a distorted square-anti­prismatic arrangement, while the CoII cation, located on an inversion center, is coordinated by two pyridyl-N atoms, two carboxyl­ate-O atoms and two water mol­ecules in a distorted octa­hedral geometry. The asymmetric unit contains two anionic L ligands: one bridges two Gd cations and one Co cation through two carboxyl groups and one pyridine-N atom; the other bridges two Gd cations and one Co cation through two carboxyl groups and the uncoordinated pyridine-N atom is hydrogen-bonded to the adjacent coordinated water mol­ecule. Extensive O—H⋯O and N—H⋯O hydrogen bonds are present in the crystal structure. PMID:22064912

  20. Development of novel tetra- and trinucleotide microsatellite markers for giant grouper Epinephelus lanceolatus using 454 pyrosequencing.

    PubMed

    Kim, Keun-Sik; Noh, Choong Hwan; Moon, Shin-Joo; Han, Seung-Hee; Bang, In-Chul

    2016-06-01

    Giant grouper (Epinephelus lanceolatus) is a commercially important species, but its wild population has recently been classified as vulnerable. This species has significant potential for use in aquaculture, though a greater understanding of population genetics is necessary for selective breeding programs to minimize kinship for genetically healthy individuals. High-throughput pyrosequencing of genomic DNA was used to identify and characterize novel tetra- and trinucleotide microsatellite markers in giant grouper from Sabah, Malaysia. In total, of 62,763 sequences containing simple sequence repeats (SSRs) were obtained, and 78 SSR loci were selected to possibly contain tetra- and trinucleotide repeats. Of these loci, 16 had tetra- and 8 had trinucleotide repeats, all of which exhibited polymorphisms within easily genotyped regions. A total of 143 alleles were identified with an average of 5.94 alleles per locus, with mean observed and expected heterozygosities of 0.648 and 0.620, respectively. Among of them, 15 microsatellite markers were identified without null alleles and with Hardy-Weinberg equilibrium. These alleles showed a combined non-exclusion probability of 0.01138. The probability of individual identification (PID) value combined with in descending order 12 microsatellite markers was 0.00008, which strongly suggests that the use of the microsatellite markers developed in this study in various combinations would result in a high resolution method for parentage analysis and individual identification. These markers could be used to establish a broodstock management program for giant grouper and to provide a foundation for genetic studies such as population structure, parentage analysis, and kinship selection. PMID:27059503

  1. Synthesis and characterization of monomolecular DNA G-quadruplexes formed by tetra-end-linked oligonucleotides.

    PubMed

    Oliviero, Giorgia; Amato, Jussara; Borbone, Nicola; Galeone, Aldo; Petraccone, Luigi; Varra, Michela; Piccialli, Gennaro; Mayol, Luciano

    2006-01-01

    Guanine-rich DNA sequences are widely dispersed in the eukaryotic genome and are abundant in regions with relevant biological significance. They can form quadruplex structures stabilized by guanine quartets. These structures differ for number and strand polarity, loop composition, and conformation. We report here the syntheses and the structural studies of a set of interconnected d(TG(4)T) fragments which are tethered, with different orientations, to a tetra-end-linker in an attempt to force the formation of specific four-stranded DNA quadruplex structures. Two synthetic strategies have been used to obtain oligodeoxyribonucleotide (ODN) strands linked with their 3'- or 5'-ends to each of the four arms of the linker. The first approach allowed the synthesis of tetra-end-linked ODN (TEL-ODN) containing the four ODN strands with a parallel orientation, while the latter synthetic pathway led to the synthesis of TEL-ODNs each containing antiparallel ODN pairs. The influence of the linker at 3'- or 5'-ODN, on the quadruplex typology and stability, in the presence of sodium or potassium ions, has been investigated by circular dichroism (CD), CD thermal denaturation, (1)H NMR experiments at variable temperature, and molecular modeling. All synthesized TEL-ODNs formed parallel G-quadruplex structures. Particularly, the TEL-ODN containing all parallel ODN tracts formed very stable parallel G-quadruplex complexes, whereas the TEL-ODNs containing antiparallel ODN pairs led to relatively less stable parallel G-quadruplexes. The molecular modeling data suggested that the above antiparallel TEL-ODNs can adopt parallel G-quadruplex structures thanks to a considerable folding of the tetra-end-linker around the whole quadruplex scaffold.

  2. Tetra-aqua-bis-[2-(2-nitro-phen-yl)acetato-κO]cobalt(II).

    PubMed

    Danish, Muhammad; Tahir, Muhammad Nawaz; Iftikhar, Sana; Raza, Muhammad Asam; Ashfaq, Muhammad

    2015-03-01

    The mol-ecule of the title compound, [Co(C8H6NO4)2(H2O)4], is centrosymmetric. It is a cobalt(II) complex, bearing two (2-nitro-phen-yl)acetate and four aqua ligands. The coordination around the Co(II) atom is distorted octa-hedral, defined by four O atoms of water mol-ecules in the equatorial plane and by two carboxyl-ate O atoms at axial positions. The dihedral angles between the benzene ring and the acetate and nitro groups are 61.90 (10) and 19.21 (11)°, respectively. The water mol-ecules form O-H⋯O hydrogen bonds with the nitro and carboxyl-ate groups, leading to a layered structural arrangement parallel to (001).

  3. The effects of UV irradiation on titania deposition from titanium tetra-isopropoxide

    NASA Astrophysics Data System (ADS)

    Egashira, Yasuyuki; Sugimachi, Masato; Nishizawa, Kouichi; Saito, Kazunobu; Osawa, Toshio; Komiyama, Hiroshi

    1994-05-01

    The influence of UV irradiation on the deposition of titania from titanium tetra-isopropoxide (TTIP) under reduced pressure was studied. It was found that UV irradiation accelerates the titania growth rate by a factor of 2-3 in the temperature range of 573 to 623 K. The coverage quality of micron-size trenches in the cases with and without UV irradiation indicates the role of the photo-enhanced surface reaction. The threshold wavelength of 380 nm which is equivalent to the energy gap of anatase indicates strongly that band-to-band excitation is responsible for the photo-enhanced surface reaction.

  4. Communication: Substrate induced dehydrogenation: Transformation of octa-ethyl-porphyrin into tetra-benzo-porphyrin

    NASA Astrophysics Data System (ADS)

    van Vörden, D.; Lange, M.; Schmuck, M.; Schaffert, J.; Cottin, M. C.; Bobisch, C. A.; Möller, R.

    2013-06-01

    Individual molecules of octa-ethyl-porhphyrin-iron(III)-chloride adsorbed on a Cu(111) surface are studied by scanning tunneling microscopy. Upon moderate heating the molecules are found to transform into Fe-tetra-benzo-porphyrin at a surprisingly low temperature of 380 K. If the annealing is interrupted, the different steps of the transformation can be imaged. By evaluating the ratio of transformed molecules as function of annealing temperature, an approximate activation energy of 1.2 eV ± 0.1 eV could be determined.

  5. 1,3-Bis(pyridin-2-yl)-1H-benzimidazol-3-ium tetra­fluoridoborate

    PubMed Central

    Grieco, Gabriele; Blacque, Olivier; Berke, Heinz

    2011-01-01

    The asymmetric unit of the title compound, C17H13N4 +·BF4 −, contains one half of the benzimidazolium cation and one half of the tetra­fluoridoborate anion, with crystallographic mirror planes bis­ecting the mol­ecules. One F atom of the tetra­fluoridoborate is equally disordered about a crystallographic mirror plane. In the crystal, C—H⋯F inter­actions link the cations and anions into layers parallel to (100). The crystal packing is further stabilized by F⋯π contacts involving the tetra­fluoridoborate anions and the five-membered rings [F⋯centroid = 2.811 (2) Å]. PMID:22091091

  6. Crystal structure of non-centrosymmetric bis-(4-meth-oxy-benzyl-ammonium) tetra-chlorido-zincate.

    PubMed

    Mahbouli Rhouma, Najla; Rayes, Ali; Mezzadri, Francesco; Calestani, Gianluca; Loukil, Mohamed

    2016-07-01

    The structure of the title non-centrosymmetric organic-inorganic hybrid salt, (C8H12NO)2[ZnCl4], consists of two 4-meth-oxy-benzyl-ammonium cations sandwiched between anionic layers, formed by isolated tetra-chlorido-zincate tetra-hedra. The double layers extend parallel to the ac plane. The crystal packing is assured by Coulombic inter-actions and by a complex N-H⋯Cl and C-H⋯Cl hydrogen-bonding system mostly involving the positively charged ammonium groups and the chloride ligands of the isolated tetra-hedral [ZnCl4](2-) units. One of the methyl-ene-ammonium groups is disordered over two sets of sites in a 0.48 (2):0.52 (2) ratio. The crystal investigated was twinned by non-merohedry with a twin component ratio of 0.738 (2):0.262 (2). PMID:27555961

  7. Crystal structure of an unknown tetra-hydro-furan solvate of tetra-kis-(μ 3-cyanato-κ(3) N:N:N)tetra-kis-[(triphenyl-phosphane-κP)-silver(I)].

    PubMed

    Frenzel, Peter; Schaarschmidt, Dieter; Jakob, Alexander; Lang, Heinrich

    2015-10-01

    In the title compound, [{[(C6H5)3P]Ag}4{NCO}4], a distorted Ag4N4-heterocubane core is set up by four Ag(I) ions being coordinated by the N atoms of the cyanato anions in a μ 3-bridging mode. In addition, a tri-phenyl-phosphine ligand is datively bonded to each of the Ag(I) ions. Intra-molecular Ag⋯Ag distances as short as 3.133 (9) Å suggest the presence of argentophilic (d (10)⋯d (10)) inter-actions. Five moderate-to-weak C-H⋯O hydrogen-bonding inter-actions are observed in the crystal structure, spanning a three-dimensional network. A region of electron density was treated with the SQUEEZE procedure in PLATON [Spek (2015). Acta Cryst. C71, 9-18] following unsuccessful attempts to model it as being part of disordered tetra-hydro-furan solvent mol-ecules. The given chemical formula and other crystal data do not take into account these solvent mol-ecules.

  8. Crystal structure of an unknown tetra-hydro-furan solvate of tetra-kis-(μ 3-cyanato-κ(3) N:N:N)tetra-kis-[(triphenyl-phosphane-κP)-silver(I)].

    PubMed

    Frenzel, Peter; Schaarschmidt, Dieter; Jakob, Alexander; Lang, Heinrich

    2015-10-01

    In the title compound, [{[(C6H5)3P]Ag}4{NCO}4], a distorted Ag4N4-heterocubane core is set up by four Ag(I) ions being coordinated by the N atoms of the cyanato anions in a μ 3-bridging mode. In addition, a tri-phenyl-phosphine ligand is datively bonded to each of the Ag(I) ions. Intra-molecular Ag⋯Ag distances as short as 3.133 (9) Å suggest the presence of argentophilic (d (10)⋯d (10)) inter-actions. Five moderate-to-weak C-H⋯O hydrogen-bonding inter-actions are observed in the crystal structure, spanning a three-dimensional network. A region of electron density was treated with the SQUEEZE procedure in PLATON [Spek (2015). Acta Cryst. C71, 9-18] following unsuccessful attempts to model it as being part of disordered tetra-hydro-furan solvent mol-ecules. The given chemical formula and other crystal data do not take into account these solvent mol-ecules. PMID:26594421

  9. HPC - Platforms Penta Chart

    SciTech Connect

    Trujillo, Angelina Michelle

    2015-10-08

    Strategy, Planning, Acquiring- very large scale computing platforms come and go and planning for immensely scalable machines often precedes actual procurement by 3 years. Procurement can be another year or more. Integration- After Acquisition, machines must be integrated into the computing environments at LANL. Connection to scalable storage via large scale storage networking, assuring correct and secure operations. Management and Utilization – Ongoing operations, maintenance, and trouble shooting of the hardware and systems software at massive scale is required.

  10. HPC - Facilities Penta

    SciTech Connect

    Trujillo, Angelina Michelle

    2015-10-08

    Strategy, Planning, Acquiring- very large scale computing require very large physical infrastructures, pipes, pumps, power, etc. Planning and acquiring $25M+ infrastructure projects and bringing in more power to the county takes a lot of long lead time / planning. Integration- New physical infrastructure must be integrated into our buildings, with the LANL site power and water systems, with existing infrastructure, and with the machines. Very large physical infrastructure projects are necessary. Management and Utilization – Ongoing operations, monitoring, maintenance, and trouble shooting of the physical infrastructure is required.

  11. Mechanism of variable structural colour in the neon tetra: quantitative evaluation of the Venetian blind model

    PubMed Central

    Yoshioka, S.; Matsuhana, B.; Tanaka, S.; Inouye, Y.; Oshima, N.; Kinoshita, S.

    2011-01-01

    The structural colour of the neon tetra is distinguishable from those of, e.g., butterfly wings and bird feathers, because it can change in response to the light intensity of the surrounding environment. This fact clearly indicates the variability of the colour-producing microstructures. It has been known that an iridophore of the neon tetra contains a few stacks of periodically arranged light-reflecting platelets, which can cause multilayer optical interference phenomena. As a mechanism of the colour variability, the Venetian blind model has been proposed, in which the light-reflecting platelets are assumed to be tilted during colour change, resulting in a variation in the spacing between the platelets. In order to quantitatively evaluate the validity of this model, we have performed a detailed optical study of a single stack of platelets inside an iridophore. In particular, we have prepared a new optical system that can simultaneously measure both the spectrum and direction of the reflected light, which are expected to be closely related to each other in the Venetian blind model. The experimental results and detailed analysis are found to quantitatively verify the model. PMID:20554565

  12. Intestinal and liver morphometry of the Yellow Tail Tetra (Astyanax altiparanae) fed with oregano oil.

    PubMed

    Ferreira, Pollyanna M F; Caldas, Débora W; Salaro, Ana Lúcia; Sartori, Sirlene S R; Oliveira, Jerusa M; Cardoso, Alex J S; Zuanon, Jener A S

    2016-01-01

    This study aimed to evaluate the effect of oregano oil on the intestinal and liver morphometry of yellow tail tetra, Astyanax altiparanae. Fish (1.46 ± 0.09 g) were kept in a 60-L aquaria, at a stocking density of 0.5 fi sh L-1. Six diets containing varying amounts of oregano oil were evaluated (0.0; 0.5; 1.0; 1.5; 2.0 and 2.5 g of oregano oil kg-1). At the end of 90 days, the fi sh were euthanised. Four intestines and four livers were collected per treatment, which were fi xed in Bouin and embedded in resin. For height and width folds, the absorption surface area and thickness of the muscular layer a positive linear effect of oregano oil was observed. A decrescent linear effect on the total number of goblet cells was also observed. For the cytoplasmic percentage of hepatocytes and liver glycogen, a positive linear effect of oregano oil was observed. There was a decreasing linear effect on the percentage of nuclei in the hepatocytes and capillaries. Thus, the oregano essential oil promotes increased absorption areas, modulates the amount of goblet cells involved in protecting the intestinal mucosa and promotes cytoplasmic increase with greater deposition of liver glycogen in yellow tail tetra. PMID:27331801

  13. Bis(tetra-ethyl-ammonium) bis-(hydrogen l-tartrate) l-tartaric acid monohydrate.

    PubMed

    Rajalakshmi, M; Indirajith, R; Gopalakrishnan, R; Ramamurthi, K; Stoeckli-Evans, Helen

    2011-06-01

    In the title compound, 2C(8)H(20)N(+)·2C(4)H(5)O(6) (-)·C(4)H(6)O(6)·H(2)O, the presence of the two tetra-ethyl-ammonium cations is balanced by two hydrogen l-tartrate anions. Also present in the asymmetric unit are a mol-ecule of l-tartaric acid and a water mol-ecule. The various components are linked by O-H⋯O hydrogen bonds. In the crystal, two-dimensional networks are formed via O-H⋯O hydrogen bonds and C-H⋯O inter-actions involving the water mol-ecule, the hydrogen l-tartrate anions and the l-tartaric acid mol-ecules. These layers, which stack along [001], are separated by tetra-ethyl-ammonium cations. The latter are also involved in C-H⋯O inter-actions with the anions and the l-tartaric acid and water mol-ecules participating in the two-dimensional network.

  14. The 3He long-counter TETRA at the ALTO ISOL facility

    NASA Astrophysics Data System (ADS)

    Testov, D.; Verney, D.; Roussière, B.; Bettane, J.; Didierjean, F.; Flanagan, K.; Franchoo, S.; Ibrahim, F.; Kuznetsova, E.; Li, R.; Marsh, B.; Matea, I.; Penionzhkevich, Yu.; Pai, H.; Smirnov, V.; Sokol, E.; Stefan, I.; Suzuki, D.; Wilson, J. N.

    2016-04-01

    A new β-decay station (BEDO) has been installed behind the PARRNe mass separator operated on-line at the electron-driven ALTO ISOL facility. The station is equipped with a movable tape collector allowing the creation of the radioactive sources of interest at the very center of a modular detection system. The mechanical structure was designed to host various assemblies of detectors in compact geometry. We report here the first on-line use of this system equipped with the 4π 3He neutron counter TETRA built at JINR Dubna associated with HPGe and plastic 4π β detectors. The single neutron detection efficiency achieved is 53(2)% measured using the 252Cf source. For β-delayed neutron measurements the neutron detection efficiency was derived from the comparison of gated γ-spectra. The on-line commissioning of the TETRA setup was performed with laser-ionized gallium beams. β and neutron events were recorded as a function of time. From these data we report P1n(82Ga)=22(2)% and T1/2(82Ga)=0.604(11) s in good agreement with values available in the literature. The new detection system will be used in other experiments aimed at investigations of β-decay properties of neutron-rich isotopes produced at ALTO.

  15. Mechanism of variable structural colour in the neon tetra: quantitative evaluation of the Venetian blind model.

    PubMed

    Yoshioka, S; Matsuhana, B; Tanaka, S; Inouye, Y; Oshima, N; Kinoshita, S

    2011-01-01

    The structural colour of the neon tetra is distinguishable from those of, e.g., butterfly wings and bird feathers, because it can change in response to the light intensity of the surrounding environment. This fact clearly indicates the variability of the colour-producing microstructures. It has been known that an iridophore of the neon tetra contains a few stacks of periodically arranged light-reflecting platelets, which can cause multilayer optical interference phenomena. As a mechanism of the colour variability, the Venetian blind model has been proposed, in which the light-reflecting platelets are assumed to be tilted during colour change, resulting in a variation in the spacing between the platelets. In order to quantitatively evaluate the validity of this model, we have performed a detailed optical study of a single stack of platelets inside an iridophore. In particular, we have prepared a new optical system that can simultaneously measure both the spectrum and direction of the reflected light, which are expected to be closely related to each other in the Venetian blind model. The experimental results and detailed analysis are found to quantitatively verify the model.

  16. Water dynamics in aqueous solutions of tetra-n-alkylammonium salts: hydrophobic and Coulomb interactions disentangled.

    PubMed

    van der Post, Sietse T; Scheidelaar, Stefan; Bakker, Huib J

    2013-12-01

    We studied the effects of tetra-n-alkylammonium bromide (N(C(n)H(2n+1))(4)(+)Br(-)) salts on the dynamics of water using polarization-resolved femtosecond infrared spectroscopy. With this technique, we are capable of distinguishing the response of water solvating the hydrophobic cations from that of water solvating the bromide anion. We observe that both types of ions slow down the orientational dynamics of the water molecules in their solvation shells. However, the nature of this slowdown is different for both ions. For the hydrophobic cation, we find an increasing number of retarded water molecules, scaling with the alkyl chain length. Water in the bromide solvation shell experiences a partial decay of its orientation by a fast wobbling motion, after which the remaining anisotropy decays much slower. The dynamics of the wobbling motion are observed to be dependent on the nature of the cation. For Me(4)NBr, the slow reorientation time is not concentration-dependent, and no aggregation is observed. This is in contrast to the tetra-n-alkylammonium salts with longer alkyl chains, for which the slow reorientation time of bromide-bound water molecules increases dramatically with concentration, and clusters of cations and anions appear to be formed. PMID:24228939

  17. Intestinal and liver morphometry of the Yellow Tail Tetra (Astyanax altiparanae) fed with oregano oil.

    PubMed

    Ferreira, Pollyanna M F; Caldas, Débora W; Salaro, Ana Lúcia; Sartori, Sirlene S R; Oliveira, Jerusa M; Cardoso, Alex J S; Zuanon, Jener A S

    2016-01-01

    This study aimed to evaluate the effect of oregano oil on the intestinal and liver morphometry of yellow tail tetra, Astyanax altiparanae. Fish (1.46 ± 0.09 g) were kept in a 60-L aquaria, at a stocking density of 0.5 fi sh L-1. Six diets containing varying amounts of oregano oil were evaluated (0.0; 0.5; 1.0; 1.5; 2.0 and 2.5 g of oregano oil kg-1). At the end of 90 days, the fi sh were euthanised. Four intestines and four livers were collected per treatment, which were fi xed in Bouin and embedded in resin. For height and width folds, the absorption surface area and thickness of the muscular layer a positive linear effect of oregano oil was observed. A decrescent linear effect on the total number of goblet cells was also observed. For the cytoplasmic percentage of hepatocytes and liver glycogen, a positive linear effect of oregano oil was observed. There was a decreasing linear effect on the percentage of nuclei in the hepatocytes and capillaries. Thus, the oregano essential oil promotes increased absorption areas, modulates the amount of goblet cells involved in protecting the intestinal mucosa and promotes cytoplasmic increase with greater deposition of liver glycogen in yellow tail tetra.

  18. Synthesis, characterization, antimicrobial, DNA binding and cleavage studies of mixed ligand Cu(II), Co(II) complexes.

    PubMed

    Leela, D Shiva; Ushaiah, B; Anupama, G; Sunitha, M; Kumari, C Gyana

    2015-01-01

    The mixed ligand complexes MLA of Cu(II) and Co(II) with Schiff base derived from 4-amino antipyrine and 5-NO(2) salicylaldehyde (2,3 -dimethyl-1-phenyl-4-(2-hydroxy-5-nitro benzylideneamino)-pyrazol-5-one) as ONO donor (L) and A = 2,2 bipyridine (bpy),1,10 phenonthroline (1,10 phen) as N, N donor ligands have been prepared, owing to their biological and other applications. The structural features have arrived from their elemental analyses, magnetic susceptibility, molar conductance, Mass, IR, UV-VIS, powdered XRD and ESR spectral studies, that established MLA type of composition for the metal complexes. The electronic absorption spectral data of the complexes suggest an octahedral geometry around the central metal ion. The interaction of the complexes with Calf Thymus (CT) DNA has been studied using absorption spectra, viscosity measurements and fluorescence spectra. The binding constants (K(b)) of the complexes were determined as 2.1 × 10(6) M(-1) for complex 1, 2.5x10(6)M(-1) for complex 2, 1.16 × 10(6) M(-1) for complex 3,1.25x10(6)M(-1) for complex 4, DNA cleavage experiments performed on pBR-322 plasmids using metal complexes in the presence of H(2)O(2) showed that all the complexes afford a pronounced DNA cleavage. Molecular modelling studies were also performed to confirm the geometries of the complexes. The ligand and their metal complexes were screened for their antimicrobial activity against bacteria. The results showed that the metal complexes are biologically active. PMID:25548074

  19. 40 CFR 180.1281 - S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1-cyclohex-2-enyl)-3-methyl-penta-(2Z,4E...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1-cyclohex-2-enyl)-3-methyl-penta-(2Z,4E)-dienoic Acid; exemption from the... Exemptions From Tolerances § 180.1281 S-Abscisic Acid,...

  20. Molecular instability in the COII-tRNA(Lys) intergenic region of the human mitochondrial genome: multiple origins of the 9-bp deletion and heteroplasmy for expanded repeats.

    PubMed Central

    Thomas, M G; Cook, C E; Miller, K W; Waring, M J; Hagelberg, E

    1998-01-01

    We have identified two individuals from Glasgow in Scotland who have a deletion of one of two copies of the intergenic 9-bp sequence motif CCCCCTCTA, located between the cytochrome oxidase II (COII) and lysine tRNA (tRNA(Lys)) genes of the human mitochondrial genome. Although this polymorphism is common in Africa and Asia, it has not been reported in Northern Europe. Analysis of the mitochondrial DNA control region sequences of these two individuals suggests that they belong to a lineage that originated independently of the previously characterized African and Asian 9-bp deleted lineages. Among the Scottish population we have also identified a maternal lineage of three generations exhibiting heteroplasmy for two, three and four copies of the CCCCCTCTA motif. Polymerase chain reaction amplification across the COII-tRNA(Lys) intergenic region of these individuals gives different ratios of the three product lengths that are dependent on the concentration of the DNA-binding dye crystal violet. To investigate whether changes in repeat number were generated de novo, we constructed clones containing known numbers of the CCCCCTCTA motif. In the presence of high concentrations of crystal violet we obtained two, three and four copies of this motif when the amplification template contained only four copies. Various DNA-binding drugs are known to stabilize bulged structures in DNA and contribute to the process of slipped-strand mispairing during DNA replication. These results suggest that the COII-tRNA(Lys) intergenic region is unstable owing to slipped-strand mispairing. Although sequences containing four copies of the CCCCCTCTA motif are less stable in vitro, we observed an increase in the proportion of mitochondrial genomes with four repeats between-a mother and a daughter in the heteroplasmic lineage. From this we conclude that drift in the germ-line lineage is a main factor in the maintenance or loss of heteroplasmy. PMID:9684291

  1. Novel FeII and CoII Complexes of Natural Product Tryptanthrin: Synthesis and Binding with G-Quadruplex DNA

    PubMed Central

    Zhong, Yi-ning; Zhang, Yan; Gu, Yun-qiong; Wu, Shi-yun; Shen, Wen-ying

    2016-01-01

    Tryptanthrin is one of the most important members of indoloquinoline alkaloids. We obtained this alkaloid from Isatis. Two novel FeII and CoII complexes of tryptanthrin were first synthesized. Single-crystal X-ray diffraction analyses show that these complexes display distorted four-coordinated tetrahedron geometry via two heterocyclic nitrogen and oxygen atoms from tryptanthrin ligand. Binding with G-quadruplex DNA properties revealed that both complexes were found to exhibit significant interaction with G-quadruplex DNA. This study may potentially serve as the basis of future rational design of metal-based drugs from natural products that target the G-quadruplex DNA.

  2. Novel FeII and CoII Complexes of Natural Product Tryptanthrin: Synthesis and Binding with G-Quadruplex DNA

    PubMed Central

    Zhong, Yi-ning; Zhang, Yan; Gu, Yun-qiong; Wu, Shi-yun; Shen, Wen-ying

    2016-01-01

    Tryptanthrin is one of the most important members of indoloquinoline alkaloids. We obtained this alkaloid from Isatis. Two novel FeII and CoII complexes of tryptanthrin were first synthesized. Single-crystal X-ray diffraction analyses show that these complexes display distorted four-coordinated tetrahedron geometry via two heterocyclic nitrogen and oxygen atoms from tryptanthrin ligand. Binding with G-quadruplex DNA properties revealed that both complexes were found to exhibit significant interaction with G-quadruplex DNA. This study may potentially serve as the basis of future rational design of metal-based drugs from natural products that target the G-quadruplex DNA. PMID:27698647

  3. Bis{2-[2,5-bis­(pyridin-2-yl)-1H-imidazol-4-yl]pyridinium} tetra­cyanidoplatinate(II) tetra­hydrate

    PubMed Central

    Gámez-Heredia, Raquel; Navarro, Rosa E.; Höpfl, Herbert; Cruz-Enríquez, Adriana; Campos-Gaxiola, José J.

    2013-01-01

    The asymmetric unit of the title hydrated complex salt, (C18H14N5)2[Pt(CN)4]·4H2O, consists of one 2-[2,5-bis­(pyridin-2-yl)-1H-imidazol-4-yl]pyridinium cation, half a tetra­cyanidoplatinate(II) dianion, which is located about a crystallographic inversion center, and two water mol­ecules of crystallization. The PtII atom has a square-planar coordination environment, with Pt—CCN distances of 1.992 (4) and 2.000 (4) Å. In the cation, there is an N—H⋯N hydrogen bond linking adjacent pyridinium and pyridine rings in positions 4 and 5. Despite this, the organic component is non-planar, as shown by the dihedral angles of 10.3 (2), 6.60 (19) and 15.66 (18)° between the planes of the central imidazole ring and the pyridine/pyridinium substituents in the 2-, 4- and 5-positions. In the crystal, cations and anions are linked via O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming a three-dimensional network. Additional π–π, C—H⋯O and C—H⋯N contacts provide stabilization to the crystal lattice. PMID:23794972

  4. Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity.

    PubMed

    Wallace, Denise; Eltiti, Stacy; Ridgewell, Anna; Garner, Kelly; Russo, Riccardo; Sepulveda, Francisco; Walker, Stuart; Quinlan, Terence; Dudley, Sandra; Maung, Sithu; Deeble, Roger; Fox, Elaine

    2012-01-01

    Terrestrial Trunked Radio (TETRA) technology ("Airwave") has led to public concern because of its potential interference with electrical activity in the brain. The present study is the first to examine whether acute exposure to a TETRA base station signal has an impact on cognitive functioning and physiological responses. Participants were exposed to a 420 MHz TETRA signal at a power flux density of 10 mW/m(2) as well as sham (no signal) under double-blind conditions. Fifty-one people who reported a perceived sensitivity to electromagnetic fields as well as 132 controls participated in a double-blind provocation study. Forty-eight sensitive and 132 control participants completed all three sessions. Measures of short-term memory, working memory, and attention were administered while physiological responses (blood volume pulse, heart rate, skin conductance) were monitored. After applying exclusion criteria based on task performance for each aforementioned cognitive measure, data were analyzed for 36, 43, and 48 sensitive participants for these respective tasks and, likewise, 107,125, and 129 controls. We observed no differences in cognitive performance between sham and TETRA exposure in either group; physiological response also did not differ between the exposure conditions. These findings are similar to previous double-blind studies with other mobile phone signals (900-2100 MHz), which could not establish any clear evidence that mobile phone signals affect health or cognitive function.

  5. Crystal structure of μ-1κC:2(η2)-carbonyl-carbonyl-1κC-chlorido-2κCl-μ-chlorido­borylene-1:2κ2 B:B-[1(η5)-penta­methyl­cyclo­penta­dien­yl](tri­cyclo­hexyl­phosphane-2κP)iron(II)platinum(II) benzene monosolvate

    PubMed Central

    Braunschweig, Holger; Kramer, Thomas

    2014-01-01

    In the mol­ecular structure of the dinuclear title compound [η5-(C5(CH3)5)(CO)Fe{(μ-BCl)(μ-CO)}PtCl(P(C6H11)3)]·C6H6, the two metal atoms, iron(II) and platinum(II), are bridged by one carbonyl (μ-CO) and one chlorido­borylene ligand (μ-BCl). The PtII atom is additionally bound to a chloride ligand situated trans to the bridging borylene, and a tri­cyclo­hexyl­phosphane ligand (PCy3) trans to the carbonyl ligand, forming a distorted square-planar structural motif at the PtII atom. The FeII atom is bound to a penta­methyl­cyclo­penta­dienyl ligand [η5-C5(CH3)5] and one carbonyl ligand (CO), forming a piano-stool structure. Additionally, one benzene solvent mol­ecule is incorporated into the crystal structure, positioned staggered relative to the penta­methyl­cyclo­penta­dienyl ligand at the FeII atom, with a centroid–centroid separation of 3.630 (2) Å. PMID:25484763

  6. Oenothera paradoxa defatted seeds extract and its bioactive component penta-O-galloyl-β-D-glucose decreased production of reactive oxygen species and inhibited release of leukotriene B4, interleukin-8, elastase, and myeloperoxidase in human neutrophils.

    PubMed

    Kiss, Anna K; Filipek, Agnieszka; Czerwińska, Monika; Naruszewicz, Marek

    2010-09-22

    In this study, we analyzed ex vivo the effect of an aqueous extract of Oenothera paradoxa defatted seeds on the formation of neutrophil-derived oxidants. For defining active compounds, we also tested lypophilic extract constituents such as gallic acid, (+)-catechin, ellagic acid, and penta-O-galloyl-β-D-glucose and a hydrophilic fraction containing polymeric procyanidins. The anti-inflammatory potential of the extract and compounds was tested by determining the release from activated neutrophils of elastase, myeloperoxidase, interleukin-8 (IL-8), and leukotriene B4 (LTB4), which are considered relevant for the pathogenesis of cardiovascular diseases. The extract of O. paradoxa defatted seeds displays potent antioxidant effects against both 4β-phorbol-12β-myristate-α13-acetate- and formyl-met-leu-phenylalanine-induced reactive oxygen species production in neutrophils with IC50 values around 0.2 μg/mL. All types of polyphenolics present in the extract contributed to the extract antioxidant activity. According to their IC50 values, penta-O-galloyl-β-D-glucose was the more potent constituent of the extract. In cell-free assays, we demonstrated that this effect is partially due to the scavenging of O2- and H2O2 oxygen species. The extract and especially penta-O-galloyl-β-D-glucose significantly inhibit elastase, myeloperoxidase IL-8, and LTB4 release with an IC50 for penta-O-galloyl-β-D-glucose of 17±1, 15±1, 6.5±2.5, and around 20 μM, respectively. The inhibition of penta-O-galloyl-β-D-glucose on reactive oxygen species and especially on O2- production, myeloperoxidase, and chemoattractant release may reduce the interaction of polymorphonuclear leukocyte with the vascular endothelium and by that potentially diminish the risk of progression of atherosclerosis development.

  7. Bioactivity-guided isolation of 1,2,3,4,6-Penta-O-galloyl-D-glucopyranose from Paeonia lactiflora roots as a PTP1B inhibitor.

    PubMed

    Baumgartner, Renate R; Steinmann, Dirk; Heiss, Elke H; Atanasov, Atanas G; Ganzera, Markus; Stuppner, Hermann; Dirsch, Verena M

    2010-09-24

    The inhibition of protein tyrosine phosphatase 1B (PTP1B) is of substantial interest for the treatment of type-2 diabetes mellitus. Using an in vitro enzyme assay with human recombinant PTP1B 1,2,3,4,6-penta-O-galloyl-D-glucopyranose was isolated from the roots of Paeonia lactiflora as an inhibitor of PTP1B, with an IC(50) value of 4.8 μM. Additionally, 1 was shown to act as an insulin sensitizer in human hepatoma cells (HCC-1.2) at a concentration of 10 μM. Thus, a potential new mechanism of action is provided explaining the antidiabetic properties of P. lactiflora.

  8. Effects of penta-O-galloyl-β-D-glucose on human neutrophil function: significant down-regulation of L-selectin expression.

    PubMed

    Kiss, Anna K; Filipek, Agnieszka; Zyżyńska-Granica, Barbara; Naruszewicz, Marek

    2013-07-01

    Penta-O-galloyl-β-D-glucose (PGG) occurrs in high concentrations in medicinal herbs such as Rhus chinensis, Paeonia suffruticosa, Acer truncatum and Terminalia chebula, which demonstrate anti-inflammatory activity. We investigated the effect of PGG on stimulated and non-stimulated neutrophils in processes which included reactive oxygen species generation (ROS), metalloproteinase-9 and interleukin-8 secretion (IL-8), β₂ integrin (CD11b) and L-selectin (CD62L) expression and apoptosis. In concentrations of 5 μM-20 μM, PGG demonstrated statistically significant inhibition of ROS generation, IL-8 secretion and β₂ integrin expression in stimulated neutrophils. The inhibition of L-selectin expression by PGG resulted in prevention in neutrophils' endothelial attachment. The result obtained may explain the anti-inflammatory activity of this compound and underline the contribution of PGG in the activity of PGG rich plant extracts.

  9. Gelation mechanism of tetra-armed poly(ethylene glycol) in aprotic ionic liquid containing nonvolatile proton source, protic ionic liquid.

    PubMed

    Hashimoto, Kei; Fujii, Kenta; Nishi, Kengo; Sakai, Takamasa; Yoshimoto, Nobuko; Morita, Masayuki; Shibayama, Mitsuhiro

    2015-04-01

    We report the gelation mechanism of tetra-armed prepolymer chains in typical aprotic ionic liquid (aIL), i.e., A-B type cross-end coupling reaction of tetra-armed poly(ethylene glycol)s with amine and activated ester terminals (TetraPEG-NH2 and TetraPEG-NHS, respectively) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide ([C2mIm][TFSA]). In the ion gel system, we focused on the pH (or H(+) concentration) dependence of the gelation reaction. We thus applied the protic ionic liquid (pIL), 1-ethylimidazolium TFSA ([C2ImH][TFSA]), as a nonvolatile H(+) source, and added it into the solvent aIL. It was found that the gelation time of TetraPEG ion gel can be successfully controlled from 1 min to 3 h depending on the concentration of pIL (cpIL = 0-3 mM). This suggests that the acid-base properties of TetraPEG-NH2 showing acid-base equilibrium (-NH2 + H(+) ⇆ -NH3(+)) in the solutions play a key role in the gelation process. The acid dissociation constants, pKa's of TetraPEG-NH3(+) and C2ImH(+) (cation of pIL) in aIL were directly determined by potentiometric titration to be 16.4 and 13.7, respectively. This indicates that most of the H(+) ions bind to TetraPEG-NH2 and then C2ImH(+) exists as neutral C2Im. The reaction efficiency of amide bond (cross-linked point) systematically decreased with increasing cpIL, which was reflected to the mechanical strength of the ion gels. From these results, we discuss the gelation mechanism of TetraPEG in aIL to point out the relationship between polymer network structure and [H(+)] in the solutions. PMID:25768427

  10. Is the PentaBDE replacement, tris (1,3-dichloro-2-propyl) phosphate (TDCPP), a developmental neurotoxicant? Studies in PC12 cells

    SciTech Connect

    Dishaw, Laura V.; Powers, Christina M.; Ryde, Ian T.; Roberts, Simon C.; Seidler, Frederic J.; Slotkin, Theodore A.; Stapleton, Heather M.

    2011-11-15

    Organophosphate flame retardants (OPFRs) are used as replacements for the commercial PentaBDE mixture that was phased out in 2004. OPFRs are ubiquitous in the environment and detected at high concentrations in residential dust, suggesting widespread human exposure. OPFRs are structurally similar to neurotoxic organophosphate pesticides, raising concerns about exposure and toxicity to humans. This study evaluated the neurotoxicity of tris (1,3-dichloro-2-propyl) phosphate (TDCPP) compared to the organophosphate pesticide, chlorpyrifos (CPF), a known developmental neurotoxicant. We also tested the neurotoxicity of three structurally similar OPFRs, tris (2-chloroethyl) phosphate (TCEP), tris (1-chloropropyl) phosphate (TCPP), and tris (2,3-dibromopropyl) phosphate (TDBPP), and 2,2 Prime ,4,4 Prime -tetrabromodiphenyl ether (BDE-47), a major component of PentaBDE. Using undifferentiated and differentiating PC12 cells, changes in DNA synthesis, oxidative stress, differentiation into dopaminergic or cholinergic neurophenotypes, cell number, cell growth and neurite growth were assessed. TDCPP displayed concentration-dependent neurotoxicity, often with effects equivalent to or greater than equimolar concentrations of CPF. TDCPP inhibited DNA synthesis, and all OPFRs decreased cell number and altered neurodifferentiation. Although TDCPP elevated oxidative stress, there was no adverse effect on cell viability or growth. TDCPP and TDBPP promoted differentiation into both neuronal phenotypes, while TCEP and TCPP promoted only the cholinergic phenotype. BDE-47 had no effect on cell number, cell growth or neurite growth. Our results demonstrate that different OPFRs show divergent effects on neurodifferentiation, suggesting the participation of multiple mechanisms of toxicity. Additionally, these data suggest that OPFRs may affect neurodevelopment with similar or greater potency compared to known and suspected neurotoxicants.

  11. Theoretical Modeling of the Magnetic Behavior of Thiacalix[4]arene Tetranuclear Mn(II)2Gd(III)2 and Co(II)2Eu(III)2 Complexes.

    PubMed

    Aldoshin, Sergey M; Sanina, Nataliya A; Palii, Andrew V; Tsukerblat, Boris S

    2016-04-01

    In view of a wide perspective of 3d-4f complexes in single-molecule magnetism, here we propose an explanation of the magnetic behavior of the two thiacalix[4]arene tetranuclear heterometallic complexes Mn(II)2Gd(III)2 and Co(II)2Eu(III)2. The energy pattern of the Mn(II)2Gd(III)2 complex evaluated in the framework of the isotropic exchange model exhibits a rotational band of the low-lying spin excitations within which the Landé intervals are affected by the biquadratic spin-spin interactions. The nonmonotonic temperature dependence of the χT product observed for the Mn(II)2Gd(III)2 complex is attributed to the competitive influence of the ferromagnetic Mn-Gd and antiferromagnetic Mn-Mn exchange interactions, the latter being stronger (J(Mn, Mn) = -1.6 cm(-1), Js(Mn, Gd) = 0.8 cm(-1), g = 1.97). The model for the Co(II)2Eu(III)2 complex includes uniaxial anisotropy of the seven-coordinate Co(II) ions and an isotropic exchange interaction in the Co(II)2 pair, while the Eu(III) ions are diamagnetic in their ground states. Best-fit analysis of χT versus T showed that the anisotropic contribution (arising from a large zero-field splitting in Co(II) ions) dominates (weak-exchange limit) in the Co(II)2Eu(III)2 complex (D = 20.5 cm(-1), J = -0.4 cm(-1), gCo = 2.22). This complex is concluded to exhibit an easy plane of magnetization (arising from the Co(II) pair). It is shown that the low-lying part of the spectrum can be described by a highly anisotropic effective spin-(1)/2 Hamiltonian that is deduced for the Co(II)2 pair in the weak-exchange limit.

  12. Photophysical and electrochemical properties of a dysprosium-zinc tetra(4-sulfonatophenyl)porphyrin complex.

    PubMed

    Chen, Wen-Tong; Liu, Dong-Sheng; Xu, Ya-Ping; Luo, Qiu-Yan; Pei, Yun-Peng

    2016-02-01

    A dysprosium-zinc porphyrin, [DyZn(TPPS)H3O]n (1) (TPPS = tetra(4-sulfonatophenyl)porphyrin), was prepared through solvothermal reactions and structurally characterized by single-crystal X-ray diffraction analyses. Complex 1 features a three-dimensional (3-D) porous open framework that is thermally stable up to 400 °C. Complex 1 displays a void space of 215 Å(3), occupying 9.2% of the unit cell volume. The fluorescence spectra reveal that it shows an emission band in the red region. The fluorescence lifetime is 39 µsec and the quantum yield is 1.7%. The cyclic voltammetry (CV) measurement revealed one quasi-reversible wave with E1/2  = 0.30 V. PMID:26014749

  13. Application of tetra-n-methylammonium hydroxide on cellulose dissolution and isolation from sugarcane bagasse.

    PubMed

    Zhong, Chao; Wang, Chunming; Wang, Fengxue; Jia, Honghua; Wei, Ping; Zhao, Yin

    2016-01-20

    Cellulose isolation, a promising way for lignocellulosic biomass utilization, is always restricted by the poor solubility of cellulose. In this paper, tetra-n-methylammonium hydroxide (TMAH) was confirmed to be capable of readily dissolving/regenerating cellulose without chemical modification at room temperature. Meanwhile, cellulose isolation from lignocellulosic biomass by initially dissolving the biomass in TMAH followed by cellulose precipitation was proposed, and the isolated substance with average cellulose purity of 92.1 ± 0.3% could be obtained throughout this process under the optimum conditions: temperature 52 °C, time 60 min, and loading ratio of TMAH/biomass (w/w) 7.2:1. Besides, high efficiency cellulose isolation (i.e. >70% cellulose purity) could be continuously remained during 4-round cycles by using the recycled TMAH solvent without distinct activity loss.

  14. Structures and spectra of complexes of tetra-tetrazole macrocycle with organic contaminants

    NASA Astrophysics Data System (ADS)

    Teng, Yifei; Du, Jingshan; Xu, Junbo; Teng, Qiwen; Wu, Shi

    2015-06-01

    The binding affinities of the tetra-tetrazole macrocycle to organic contaminants were studied using density function theory (DFT) at B3LYP/6-31G( d, p) level after the basis set superior error (BSSE). The host molecule shows the binding affinity to the guest molecules owing to the formation of the hydrogen bonds. Based on the B3LYP/6-31G( d) optimized geometries, the electronic spectra of the complexes were calculated using INDO/CIS method. The first absorption bands in the electronic spectra of most of the complexes, compared with that of the host, are red-shifted. The chemical shifts of the carbon atoms with sp 3 hybridization in the host, calculated at B3LYP/6-31G( d) level, are basically shifted upwards. The complex formed by the host and acrolein exhibits the aromaticity although the host shows the anti-aromaticity.

  15. A Tb-Zn tetra(4-sulfonatophenyl)porphyrin hybrid: Preparation, structure, photophysical and electrochemical properties

    NASA Astrophysics Data System (ADS)

    Chen, Wen-Tong; Hu, Rong-Hua; Wang, Yin-Feng; Zhang, Xian; Liu, Juan

    2014-05-01

    A terbium-zinc porphyrin, i.e. [TbZn(TPPS)H3O]n (1) (TPPS=tetra(4-sulfonatophenyl)porphyrin), has been obtained from a solvothermal reaction and structurally analyzed by single-crystal X-ray diffraction. Compound 1 is characteristic of a condensed three-dimensional (3-D) porous open framework with two types of infinite one-dimensional (1-D) chain-like structure. Compound 1 exhibits a void space of 215 Å3, which is 9.2% of the unit-cell volume. TG/DTA measurement reveals that the framework of compound 1 is thermally stable up to 336 °C. In order to reveal its photophysical and electrochemical properties, we investigated compound 1 in detail with UV-vis spectra, fluorescence, quantum yield, luminescence lifetime, and CV/DPV.

  16. Photophysical and electrochemical properties of a dysprosium-zinc tetra(4-sulfonatophenyl)porphyrin complex.

    PubMed

    Chen, Wen-Tong; Liu, Dong-Sheng; Xu, Ya-Ping; Luo, Qiu-Yan; Pei, Yun-Peng

    2016-02-01

    A dysprosium-zinc porphyrin, [DyZn(TPPS)H3O]n (1) (TPPS = tetra(4-sulfonatophenyl)porphyrin), was prepared through solvothermal reactions and structurally characterized by single-crystal X-ray diffraction analyses. Complex 1 features a three-dimensional (3-D) porous open framework that is thermally stable up to 400 °C. Complex 1 displays a void space of 215 Å(3), occupying 9.2% of the unit cell volume. The fluorescence spectra reveal that it shows an emission band in the red region. The fluorescence lifetime is 39 µsec and the quantum yield is 1.7%. The cyclic voltammetry (CV) measurement revealed one quasi-reversible wave with E1/2  = 0.30 V.

  17. 4-[4-(1H-Tetra­zol-5-yl)phen­oxy]benzaldehyde

    PubMed Central

    Lu, Jing; Xu, Jiao; Ni, Li-Wei; Ma, Wei-Li; Du, Zhen-Ting

    2011-01-01

    The asymmetric unit of the title compound, C14H10N4O2, contains two independent mol­ecules with similar structures. In one mol­ecule, the tetra­zole ring is oriented at dihedral angles of 17.71 (16) and 57.13 (17)°, respectively, to the central benzene ring and the terminal benzene ring; in the other mol­ecule, the corresponding dihedral angles are 16.46 (18) and 75.87 (18)°. Inter­molecular N—H⋯N hydrogen bonds and weak C—H⋯O and C—H⋯N hydrogen bonds occur in the crystal structure. PMID:22220109

  18. Enantioselective molecular sensing of aromatic amines using tetra-(S)-di-2-naphthylprolinol calix[4]arene.

    PubMed

    Jennings, K; Diamond, D

    2001-07-01

    This paper presents new analytical data, and evidence of the fluorescence quenching mechanism involved in enantioselective signals obtained with the chiral host tetra-(S)-di-2-naphthylprolinol calix[4]arene. Excellent selectivity is obtained with phenylglycinol and norephidrine in methanol, and samples of unknown enantiomeric composition have been determined with an average error of 1.08 and 0.62%, respectively (n = 6), on the basis of a single fluorescence measurement. The absence of any quenching observed with the related amines of phenylalaninol is attributed to a methylene spacer which inhibits efficient interaction between the aryl group of the guest and the naphthyl group of the host. The importance of the phenyl group of the guest in the quenching mechanism is confirmed by the complete absence of any quenching effect with cyclohexylethylamine. PMID:11478636

  19. Early Detection of Lung Cancer with Meso Tetra (4-Carboxyphenyl) Porphyrin-Labeled Sputum

    PubMed Central

    Patriquin, Lara; Merrick, Daniel T.; Hill, David; Holcomb, Richard G.; Lemieux, Madeleine E.; Bennett, Gordon; Karia, Bijal; Rebel, Vivienne I.; Bauer, Thomas

    2016-01-01

    Introduction Early detection of lung cancer in high-risk individuals reduces mortality. Low-dose spiral computed tomography (LDCT) is the current standard but suffers from an exceedingly high false-positive rate (>96%) leading to unnecessary and potentially dangerous procedures. We, therefore, set out to develop a simple, noninvasive, and quantitative assay to detect lung cancer. Methods This proof-of-concept study evaluated the sensitivity/specificity of the CyPath Early Lung Cancer Detection Assay to correctly classify LDCT-confirmed cohorts of high-risk control (n = 102) and cancer (n = 26) subjects. Fluorescence intensity parameters of red fluorescent cells (RFCs) from tetra (4-carboxyphe-nyl) porphyrin (TCPP)-labeled lung sputum samples and subjects’ baseline characteristics were assessed for their predictive power by multivariable logistic regression. A receiver operating characteristic curve was constructed to evaluate the sensitivity/specificity of the CyPath assay. Results RFCs were detectable in cancer subjects more often than in high-risk ones (p = 0.015), and their characteristics differed between cohorts. Two independent predictors of cancer were the mean of RFC average fluorescence intensity/area per subject (p < 0.001) and years smoked (p = 0.003). The CyPath-based classifier had an overall accuracy of 81% in the test population; false-positive rate of 40% and negative predictive value of 83%. Conclusions The tetra (4-carboxyphenyl) porphyrin-based CyPath assay correctly classified study participants into cancer or high-risk cohorts with considerable accuracy. Optimizing sputum collection, sample reading, and refining the classifier should improve sensitivity and specificity. The CyPath assay thus has the potential to complement LDCT screening or serve as a stand-alone approach for early lung cancer detection. PMID:26200451

  20. Cu(II), Co(II) and Ni(II) complexes of new Schiff base ligand: Synthesis, thermal and spectroscopic characterizations

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; El-Sayed, Mohamed Y.; Adam, Abdel Majid A.

    2013-04-01

    Cu(II), Co(II), and Ni(II) complexes were synthesized from 2-[(5-o-chlorophenylazo-2-hydroxybenzylidin)amino]-phenol Schiff base (H2L). Metal ions coordinate in a tetradentate or hexadentate features with these O2N donor ligand, which are characterized by elemental analyses, magnetic moments, infrared, Raman laser, electronic, and 1H NMR spectral studies. The elemental analysis suggests the stoichiometry to be 1:1 (metal:ligand). Reactions with Cu(II), Co(II) and Ni(II), resulted [Cu(H2L)(H2O)2(Cl)]Cl, [Co(H2L)(H2O)3]Cl2ṡ3H2O and [Ni(H2L)(H2O)2]Cl2ṡ6H2O. The thermal decomposition behavior of H2L complexes has been investigated by thermogravimetric analysis (TG/DTG) at a heating rate of 10 °C min-1 under nitrogen atmosphere. The brightness side in this study is to take advantage for the preparation and characterizations of single phases of CuO, CoO and NiO nanoparticles using H2L complexes as precursors via a solid-state decomposition procedure. The crystalline structures of products using X-ray diffractometer (XRD), morphology of particles by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) were investigated.

  1. DNA cleavage, antibacterial, antifungal and anthelmintic studies of Co(II), Ni(II) and Cu(II) complexes of coumarin Schiff bases: Synthesis and spectral approach

    NASA Astrophysics Data System (ADS)

    Patil, Sangamesh A.; Prabhakara, Chetan T.; Halasangi, Bhimashankar M.; Toragalmath, Shivakumar S.; Badami, Prema S.

    2015-02-01

    The metal complexes of Co(II), Ni(II) and Cu(II) have been synthesized from 6-formyl-7,8-dihydroxy-4-methylcoumarin with o-toluidine/3-aminobenzotrifluoride. The synthesized Schiff bases and their metal complexes were structurally characterized based on IR, 1H NMR, 13C NMR, UV-visible, ESR, magnetic, thermal, fluorescence, mass and ESI-MS studies. The molar conductance values indicate that complexes are non-electrolytic in nature. Elemental analysis reveals ML2·2H2O [M = Co(II), Ni(II) and Cu(II)] stoichiometry, where 'L' stands for a singly deprotonated ligand. The presence of co-ordinated water molecules were confirmed by thermal studies. The spectroscopic studies suggest the octahedral geometry. Redox behavior of the complexes were confirmed by cyclic voltammetry. All the synthesized compounds were screened for their antibacterial (Escherichia coli, Pseudomonas auregenosa, klebsiella, Proteus, Staphylococcus aureus and salmonella) antifungal (Candida, Aspergillus niger and Rhizopus), anthelmintic (Pheretima posthuma) and DNA cleavage (Calf Thymus DNA) activity.

  2. Synthesis, X-ray crystal structure and spectroscopy of a Werner-type host Co(II) complex, trans-bisisothiocyanatotetrakis( trans-4-styrylpyridine)cobalt(II)

    NASA Astrophysics Data System (ADS)

    Karunakaran, C.; Thomas, K. R. J.; Shunmugasundaram, A.; Murugesan, R.

    2000-05-01

    Single crystals of the title Co(II) complex, [Co(stpy) 4(NCS) 2] [stpy= trans-4-styrylpyridine] are prepared and characterized by elemental analysis, IR, and UV-visible spectroscopy and X-ray crystal structure determination. The complex crystallizes in the orthorhombic space group Pna2 1 with unit-cell parameters, a=32.058(3), b=15.362(5), c=9.818(5) Å, and Z=4. The structure consists of discrete monomeric units of [Co(stpy) 4(NCS) 2]. The equatorial positions of the Co(II) polyhedron are occupied by nitrogen atoms of the four stpy ligands and the axial positions are occupied by the nitrogen atoms of the two thiocyanate ions. The unit cell packing reveals interpenetration of styryl groups owing to conformational flexibility of phenyl and pyridyl rings in stpy ligands. Thus, it leads to efficient packing of the crystal lattice leaving no space available for guest inclusion. IR spectra reveal nitrogen coordination from stpy and terminal -NCS coordination of the thiocyanate group. The optical reflectance bands 475, 540 (shoulder) and 1022 nm suggest octahedral geometry in accordance with the X-ray data. However, the optical spectrum of acetonitrile solution shows an intense band at 615 nm and a weak shoulder at 570 nm suggesting participation of the solvent molecules in the coordination sphere. These bands indicate the presence of both tetrahedral and octahedral species in solution.

  3. N-donor co-ligands driven two new Co(II)- coordination polymers with bi- and trinuclear units: Crystal structures, and magnetic properties

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi-Hang; Han, Min-Le; Wu, Ya-Pan; Dong, Wen-Wen; Li, Dong-Sheng; Lu, Jack Y.

    2016-10-01

    Two new Co(II) coordination polymers(CPs), namely [Co2(bpe)2(Hbppc)]n (1) and [Co3(μ3-OH)(bppc)(bpm)(H2O)]·3H2O (2) (H5bppc=biphenyl-2,4,6,3‧,5‧-pentacarboxylic acid, bpe=1,2-bis(4-pyridyl)ethene, bpm=bis(4-pyridyl)amine), have been obtained and characterized by elemental analysis, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), IR spectra and thermogravimetric analysis (TGA). 1 shows a binodal (4,6)-connected fsc net with a (44·610·8)(44·62) topology, while 2 shows a binodal (5,7)-connected 3D network based on trinuclear [Co3(μ3-OH)]5+ units with unusual (3.46.52.6)(32.46.57.65.7) topology. Variable-temperature magnetic susceptibility measurements reveals that complex 1 shows ferromagnetic interactions between the adjacent Co(II) ions, whereas 2 is a antiferromagnetic system.

  4. Tetra-aqua-bis(nicotinamide-κN)cobalt(II) bis-(2-fluoro-benzoate).

    PubMed

    Ozbek, F Elif; Tercan, Barış; Sahin, Ertan; Necefoğlu, Hacali; Hökelek, Tuncer

    2009-01-01

    The title complex, [Co(C(6)H(6)N(2)O)(2)(H(2)O)(4)](C(7)H(4)FO(2))(2), contains one Co(II) atom (site symmetry ), two monodentate nicotin-amide (NA) ligands, four coordinated water mol-ecules and two 2-fluoro-benzoate (FB) anions. The four O atoms in the equatorial plane around the Co atom form a slightly distorted square-planar arrangement, while the slightly distorted octa-hedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl group and the adjacent benzene ring is 29.8 (3)°, while the pyridine and benzene rings are oriented at a dihedral angle of 7.97 (12)°. In the crystal structure, mol-ecules are linked by O-H⋯O, N-H⋯O and N-H⋯F hydrogen bonds, forming an infinite three-dimensional network. π-π Contacts between the pyridine and benzene rings [centroid-centroid distance = 3.673 (3) Å] may further stabilize the crystal structure. PMID:21582108

  5. (2,3,5,6-Tetra­fluoro­phenolato-κO)(5,10,15,20-tetra­phenyl­porphyrinato)iron(III)

    PubMed Central

    Xu, Nan; Powell, Douglas R.; Richter-Addo, George B.

    2013-01-01

    The title compound, [Fe(C44H28N4)(C6HF4O)], is a porphyrin complex with iron(III) in fivefold coordination with a tetra­fluoro­phenolate group as the axial ligand. The Fe atom and the phenolate ligand are disordered across the porphyrin ring with the two phenolates appearing to be roughly related by a center of symmetry. The occupancies of the two phenolate groups refined to 0.788 (3) for the major component and 0.212 (3) for the minor component. The structure shows extraordinary Fe displacements of 0.488 (4) (major) and 0.673 (4) Å (minor) from the 24-atom mean plane of the porphyrin. The Fe—Np distances range from 2.063 (4) to 2.187 (6) Å and the Fe—O distances are 1.903 (5) Å for major component and 1.87 (2) Å for minor component. The four phenyl groups attached to the porphyrin ring form dihedral angles of 63.4 (4), 49.6 (4), 62.4 (4), and 63.3 (4)° (in increasing numerical order) with the three nearest C atoms of the porphyrin ring. The major and minor component phenolate groups form dihedral angles of 24.9 (4)° and 24.8 (4)°, respectively, with the four porphyrin N atoms. The Fe⋯Fe distance between the two iron(III) atoms of adjacent porphyrin mol­ecules is 6.677 (3) Å. No close inter­molecular inter­action was observed. The crystal studied was twinned by inversion, with a major–minor component ratio of 0.53 (3):0.47 (3). PMID:24098188

  6. catena-Poly[[tetra­aqua­cadmium]-μ-5,5′-(1,4-phenyl­ene)di(tetra­zol-2-ido)-κ2 N 2:N 2′

    PubMed Central

    Dang, Qinqin; Caiyun, Han

    2013-01-01

    In the title compound, [Cd(C8H4N8)(H2O)4]n, 5,5′-(1,4-phenyl­ene)di(tetra­zol-2-ide) (L) ligands bridge CdII atoms into polymeric chains along [201]. The CdII atom is situated on an inversion centre and is coordinated by two N atoms from two L ligands and by four water O atoms in a distorted octa­hedral geometry. In the L ligand, the benzene ring resides on an inversion centre and the tetra­zole rings are twisted from its plane by 22.3 (1)°. An extensive hydrogen-bonding network formed by classical O—H⋯N and O—H⋯O inter­actions consolidates the crystal packing, linking the poymeric chains into a three-dimensional structure. PMID:23723784

  7. 40 CFR 721.4040 - Glycols, polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. 721.4040 Section 721.4040 Protection of...-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. (a) Chemical..., polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetramethyl butyl)phenyl ether, sodium salt (P-90-1565)...

  8. Synthesis and characterization of Co(II), Ni(II), Cu(II) and Zn(II) complexes of tridentate Schiff base derived from vanillin and DL-α-aminobutyric acid

    NASA Astrophysics Data System (ADS)

    Nair, M. Sivasankaran; Joseyphus, R. Selwin

    2008-09-01

    Co(II), Ni(II), Cu(II) and Zn(II) complexes of the Schiff base derived from vanillin and DL-α-aminobutyric acid were synthesized and characterized by elemental analysis, IR, electronic spectra, conductance measurements, magnetic measurements, powder XRD and biological activity. The analytical data show the composition of the metal complex to be [ML(H 2O)], where L is the Schiff base ligand. The conductance data indicate that all the complexes are non-electrolytes. IR results demonstrate the tridentate binding of the Schiff base ligand involving azomethine nitrogen, phenolic oxygen and carboxylato oxygen atoms. The IR data also indicate the coordination of a water molecule with the metal ion in the complex. The electronic spectral measurements show that Co(II) and Ni(II) complexes have tetrahedral geometry, while Cu(II) complex has square planar geometry. The powder XRD studies indicate that Co(II) and Cu(II) complexes are amorphous, whereas Ni(II) and Zn(II) complexes are crystalline in nature. Magnetic measurements show that Co(II), Ni(II) and Cu(II) complexes have paramagnetic behaviour. Antibacterial results indicated that the metal complexes are more active than the ligand.

  9. Tetra Primer ARMS PCR Optimization to Detect Single Nucleotide Polymorphisms of the CYP2E1 Gene.

    PubMed

    Suhda, Saihas; Paramita, Dewi Kartikawati; Fachiroh, Jajah

    2016-01-01

    Single nucleotide polymorphism (SNP) detection has been used extensively for genetic association studies of diseases including cancer. For mass, yet accurate and more economic SNP detection we have optimized tetra primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) to detect three SNPs in the cytochrome P450 2E1 (CYP2E1) gene locus; i.e. rs3813865, rs2070672 and rs3813867. The optimization system strategies used were (1) designing inner and outer primers; (2) determining of their optimum primer concentration ratios; and (3) determining of the optimum PCR annealing temperature. The tetra primer ARMS PCR result could be directly observed using agarose gel electrophoresis. The method succesfully determined three SNPs in CYP2E1 locus, the results being consistent with validation using DNA sequencing and restriction fragment length polymorphisms (RFLP). PMID:27509930

  10. Tetra Primer ARMS PCR Optimization to Detect Single Nucleotide Polymorphisms of the CYP2E1 Gene.

    PubMed

    Suhda, Saihas; Paramita, Dewi Kartikawati; Fachiroh, Jajah

    2016-01-01

    Single nucleotide polymorphism (SNP) detection has been used extensively for genetic association studies of diseases including cancer. For mass, yet accurate and more economic SNP detection we have optimized tetra primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) to detect three SNPs in the cytochrome P450 2E1 (CYP2E1) gene locus; i.e. rs3813865, rs2070672 and rs3813867. The optimization system strategies used were (1) designing inner and outer primers; (2) determining of their optimum primer concentration ratios; and (3) determining of the optimum PCR annealing temperature. The tetra primer ARMS PCR result could be directly observed using agarose gel electrophoresis. The method succesfully determined three SNPs in CYP2E1 locus, the results being consistent with validation using DNA sequencing and restriction fragment length polymorphisms (RFLP).

  11. Synthesis, characterization and in vitro antimicrobial studies of Co(II), Ni(II) and Cu(II) complexes derived from macrocyclic compartmental ligand

    NASA Astrophysics Data System (ADS)

    El-Gammal, O. A.; Bekheit, M. M.; El-Brashy, S. A.

    2015-02-01

    New Co(II), Ni(II) and Cu(II) complexes derived from tetradentate macrocyclic nitrogen ligand, (1E,4E,8E,12E)-5,8,13,16-tetramethyl-1,4,9,12-tetrazacyclohexadeca-4,8,12,16-tetraene (EDHDH) have been synthesized. The complexes have been characterized by elemental analysis, spectral (IR, UV-Vis, 1H NMR and ESR (for Cu(II) complex)) mass, and magnetic as well as thermal analysis measurements. The complexes afforded the formulae: [Cu(EDHDH)Cl2]·2EtOH and [M(EDHDH)X2]·nH2O where M = Co(II) and Ni(II), X = Cl- or OH-, n = 1,0, respectively. The data revealed an octahedral arrangement with N4 tetradentate donor sites in addition to two Cl atoms occupying the other two sites. ESR spectrum of Cu2+ complex confirmed the suggested geometry with values of a α2and β2 indicating that the in-plane σ-bonding and in-plane π-bonding are appreciably covalent, and are consistent with very strong σ-in-plane bonding in the complexes. The molecular modeling is drawn and showed the bond length, bond angle, chemical reactivity, energy components (kcal/mol) and binding energy (kcal/mol) for all the title compounds using DFT method. Also, the thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. Moreover, the in vitro antibacterial studies of all compounds screened against pathogenic bacteria (two Gram +ve and two Gram -ve) to assess their inhibiting potential. The assay indicated that the inhibition potential is metal ion dependent. The ligand, EDHDH, Co(II) and Cu(II) complexes exhibited a remarkable antibacterial activity against Streptococcus Pyogenes as Gram +ve and Proteus vulgaris as Gram -ve bacterial strains. On the other hand, Ni(II) complex revealed a moderate antibacterial activity against both Gram +ve organisms and no activity against Gram -ve bacterial strain.

  12. [μ(2)-Bis(diphenyl-phosphanyl)methane][μ(3)-bis-(diphenyl-phosphanyl)meth-yl]trichlorido-tetra-gold(I) tetra-hydro-furan disolvate.

    PubMed

    Wang, Huan-Huan; Gao, Qian; Cui, Yue; Wang, Lin; Xie, Ya-Bo

    2011-01-08

    The title tetra-nuclear complex, [Au(4)(C(25)H(21)P(2))Cl(3)(C(25)H(22)P(2))]·2C(4)H(8)O, features two non-equivalent Ph(2)PCPPh(2) fragments, one of which represents the 'complete' mol-ecule (with two H atoms at the central C atom); each of the two P atoms of this mol-ecule is coordinated by an Au atom [Au-P = 2.2256 (13) and 2.2710 (13) Å], and these two Au atoms form an Au-Au bond [3.2945 (3) Å], thus closing the five-membered Au(2)P(2)C ring. The first of these Au atoms has a terminal chlorido ligand [Au-Cl = 2.2806 (12) Å], whereas the second Au atom forms a covalent bond with the central C atom of the bis-(diphenyl-phosphino)methyl group [Au-C = 2.114 (5) Å]; the latter group in turn coordinates with its P atoms the gold atoms of the Cl-Au-Au-Cl group [Au-P = 2.2356 (13) and 2.2338 (13), Au-Au = 3.3177 (3), Au-Cl = 2.3091 (12) and 2.2950 (13) Å], thus closing the second Au(2)P(2)C ring. The two such rings have different chemical functions, but both exhibit envelope conformations. However, the first (with different substituents at the Au atoms) is non-symmetrical with one of the P atoms in the flap position of the envelope; the other one has a conformation with mirror symmetry, and the gold-substituted C atom is displaced by 0.740 (5) Å from the almost exactly planar (r.m.s. deviation = 0.0038 Å) Au(2)P(2) group.

  13. Surface-Enhanced Resonance Raman Spectra of Langmuir-Blodgett Films of Tetra-Lauryl Chloroaluminum Phthalocyanine

    NASA Astrophysics Data System (ADS)

    Luo, Tao; Zhang, Weiqing; Gan, Fuxi

    1992-07-01

    The Langmuir-Blodgett (LB) films of tetra-lauryl chloroaluminum phthalocyanine (TLAlClPc) and a 1:1 mixture of TLAlClPc and stearyl alcohol (SA) were prepared. The Raman spectrum of solid TLAlClPc in KBr pellet was investigated. All the Raman lines were assigned. The surface-enhanced resonance Raman spectra of the LB films deposited on the silver island film that were vacuum-deposited on glass slides have been observed.

  14. Preparation and use of tetra-alkyl cobalt dicarbollide for extraction of cesium and strontium into hydrocarbon solvents

    DOEpatents

    Miller, Rebecca L.; Pinkerton, Anthony B.; Abney, Kent D.; Kinkead, Scott A.

    1997-01-01

    Preparation and use of tetra-C-alkyl cobalt dicarbollide for extraction of cesium and strontium into hydrocarbon solvents. Tetra-C-alkyl derivatives of cobalt dicarbollide, Co(C.sub.2 R.sub.2 B.sub.9 H.sub.9).sub.2.sup.- (CoB.sub.2 R.sub.4.sup.- ; R=CH.sub.3 and C.sub.6 H.sub.13) are demonstrated to be significant cesium and strontium extractants from acidic and alkaline solutions into non-toxic organic solvent systems. Extractions using mesitylene and diethylbenzene are compared to those with nitrobenzene as the organic phase. CoB.sub.2 -hexyl.sub.4.sup.- in diethylbenzene shows improved selectivity (10.sup.4) for Cs over Na in acidic solution. In dilute alkaline solution, CoB.sub.2 -hexyl.sub.4.sup.- extracts Cs less efficiently, but more effectively removes Sr from higher base concentrations. A general synthesis of tetra-C-alkyl cobalt dicarbollides is described.

  15. Preparation and use of tetra-alkyl cobalt dicarbollide for extraction of cesium and strontium into hydrocarbon solvents

    DOEpatents

    Miller, R.L.; Pinkerton, A.B.; Abney, K.D.; Kinkead, S.A.

    1997-02-11

    Preparation and use of tetra-C-alkyl cobalt dicarbollide for extraction of cesium and strontium into hydrocarbon solvents. Tetra-C-alkyl derivatives of cobalt dicarbollide, Co(C{sub 2}R{sub 2}B{sub 9}H{sub 9}){sub 2}{sup {minus}}(CoB{sub 2}R{sub 4}{sup {minus}}; R=CH{sub 3} and C{sub 6}H{sub 13}) are demonstrated to be significant cesium and strontium extractants from acidic and alkaline solutions into non-toxic organic solvent systems. Extractions using mesitylene and diethylbenzene are compared to those with nitrobenzene as the organic phase. CoB{sub 2}-hexyl{sub 4}{sup {minus}} in diethylbenzene shows improved selectivity (10{sup 4}) for Cs over Na in acidic solution. In dilute alkaline solution, CoB{sub 2}-hexyl{sub 4}{sup {minus}} extracts Cs less efficiently, but more effectively removes Sr from higher base concentrations. A general synthesis of tetra-C-alkyl cobalt dicarbollides is described. 6 figs.

  16. Digital recovery, modification, and analysis of Tetra Tech seismic horizon mapping, National Petroleum Reserve Alaska (NPRA), northern Alaska

    USGS Publications Warehouse

    Saltus, R.W.; Kulander, Christopher S.; Potter, Christopher J.

    2002-01-01

    We have digitized, modified, and analyzed seismic interpretation maps of 12 subsurface stratigraphic horizons spanning portions of the National Petroleum Reserve in Alaska (NPRA). These original maps were prepared by Tetra Tech, Inc., based on about 15,000 miles of seismic data collected from 1974 to 1981. We have also digitized interpreted faults and seismic velocities from Tetra Tech maps. The seismic surfaces were digitized as two-way travel time horizons and converted to depth using Tetra Tech seismic velocities. The depth surfaces were then modified by long-wavelength corrections based on recent USGS seismic re-interpretation along regional seismic lines. We have developed and executed an algorithm to identify and calculate statistics on the area, volume, height, and depth of closed structures based on these seismic horizons. These closure statistics are tabulated and have been used as input to oil and gas assessment calculations for the region. Directories accompanying this report contain basic digitized data, processed data, maps, tabulations of closure statistics, and software relating to this project.

  17. Synthesis and library construction of privileged tetra-substituted Δ5-2-oxopiperazine as β-turn structure mimetics.

    PubMed

    Kim, Jonghoon; Lee, Won Seok; Koo, Jaeyoung; Lee, Jeongae; Park, Seung Bum

    2014-01-13

    In this study, we developed an efficient and practical procedure for the synthesis of tetra-substituted Δ5-2-oxopiperazine that mimics the bioactive β-turn structural motif of proteins. This synthetic route is robust and modular enough to accommodate four different substituents to obtain a high level of molecular diversity without any deterioration in stereochemical enrichment of the natural and unnatural amino acids. Through the in silico studies, including a distance calculation of side chains and a conformational overlapping of our model compound with a native β-turn structure, we successfully demonstrated the conformational similarity of tetra-substituted Δ5-2-oxopiperazine to the β-turn motif. For the library construction in a high-throughput manner, the fluorous tag technology was adopted with the use of a solution-phase parallel synthesis platform. A 140-membered pilot library of tetra-substituted Δ5-2-oxopiperazines was achieved with an average purity of 90% without further purification.

  18. Synthesis, spectral characterization and catalytic activity of Co(II) complexes of drugs: Crystal structure of Co(II)-trimethoprim complex

    NASA Astrophysics Data System (ADS)

    Madhupriya, Selvaraj; Elango, Kuppanagounder P.

    2014-01-01

    New Co(II) complexes with drugs such as trimethoprim (TMP), cimetidine (CTD), niacinamide (NAM) and ofloxacin (OFL) as ligands were synthesized. The complexes were characterized by analytical analysis, various spectral techniques such as FT-IR, UV-Vis, magnetic measurements and molar conductivity. The magnetic susceptibility results coupled with the electronic spectra suggested a tetrahedral geometry for the complexes. The coordination mode of trimethoprim ligand and geometry of the complex were confirmed by single crystal X-ray studies. In this complex the metal ion possesses a tetrahedral geometry with two nitrogen atom from two TMP ligands and two chloride ions coordinated to it. The catalytic activity of the complexes in aryl-aryl coupling reaction was screened and the results indicated that among the four complexes [Co(OFL)Cl(H2O)] exhibited excellent catalytic activity.

  19. Synthesis, characterization, in vitro antimicrobial and DNA cleavage studies of Co(II), Ni(II) and Cu(II) complexes with ONOO donor coumarin Schiff bases

    NASA Astrophysics Data System (ADS)

    Patil, Sangamesh A.; Unki, Shrishila N.; Kulkarni, Ajaykumar D.; Naik, Vinod H.; Badami, Prema S.

    2011-01-01

    A series of Co(II), Ni(II) and Cu(II) complexes have been synthesized with Schiff bases derived from 2-hydroxy-1-naphthaldehyde and 2-oxo-2H-chromene-3-carbohydrazide/6-bromo-2-oxo-2H-chromene-3-carbohydrazide. The chelation of the complexes has been proposed in the light of analytical, spectral (IR, UV-Vis, 1H NMR, ESR, FAB-mass and fluorescence), magnetic and thermal studies. The measured molar conductance values indicate that, the complexes are non-electrolytic in nature. The redox behavior of the complexes was investigated with electrochemical method by using cyclic voltammetry. The Schiff bases and their metal complexes have been screened for their in vitro antibacterial ( Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Salmonella typhi) and antifungal activities ( Candida albicans, Cladosporium and Aspergillus niger) by MIC method. The DNA cleavage is studied by agarose gel electrophoresis method.

  20. Two-dimensional Zn(II) and one-dimensional Co(II) coordination polymers based on benzene-1,4-dicarboxylate and pyridine ligands.

    PubMed

    Zhou, Li-Juan; Han, Chang-Bao; Wang, Yu-Ling

    2016-02-01

    Coordination polymers constructed from metal ions and organic ligands have attracted considerable attention owing to their diverse structural topologies and potential applications. Ligands containing carboxylate groups are among the most extensively studied because of their versatile coordination modes. Reactions of benzene-1,4-dicarboxylic acid (H2BDC) and pyridine (py) with Zn(II) or Co(II) yielded two new coordination polymers, namely, poly[(μ4-benzene-1,4-dicarboxylato-κ(4)O:O':O'':O''')(pyridine-κN)zinc(II)], [Zn(C8H4O2)(C5H5N)]n, (I), and catena-poly[aqua(μ3-benzene-1,4-dicarboxylato-κ(3)O:O':O'')bis(pyridine-κN)cobalt(II)], [Co(C8H4O2)(C5H5N)2(H2O)]n, (II). In compound (I), the Zn(II) cation is five-coordinated by four carboxylate O atoms from four BDC(2-) ligands and one pyridine N atom in a distorted square-pyramidal coordination geometry. Four carboxylate groups bridge two Zn(II) ions to form centrosymmetric paddle-wheel-like Zn2(μ2-COO)4 units, which are linked by the benzene rings of the BDC(2-) ligands to generate a two-dimensional layered structure. The two-dimensional layer is extended into a three-dimensional supramolecular structure with the help of π-π stacking interactions between the aromatic rings. Compound (II) has a one-dimensional double-chain structure based on Co2(μ2-COO)2 units. The Co(II) cations are bridged by BDC(2-) ligands and are octahedrally coordinated by three carboxylate O atoms from three BDC(2-) ligands, one water O atom and two pyridine N atoms. Interchain O-H...O hydrogen-bonding interactions link these chains to form a three-dimensional supramolecular architecture. PMID:26846498

  1. 9-(Dicyano­methyl­idene)fluorene–tetra­thia­fulvalene (1/1)

    PubMed Central

    Salmerón-Valverde, Amparo; Bernès, Sylvain

    2012-01-01

    The title compound, C16H8N2·C6H4S4, crystallizes with the fluorene derivative placed in a general position and two half tetra­thia­fulvalene (TTF) mol­ecules, each completed to a whole mol­ecule through an inversion center. The fluorene ring system is virtually planar (r.m.s. deviation from the mean plane = 0.027 Å) and the dicyano group is twisted from the fluorene plane by only 3.85 (12)°. The TTF mol­ecules are also planar, and their central C=C bond lengths [1.351 (8) and 1.324 (7) Å] compare well with the same bond length in neutral TTF (ca 1.35 Å). These features indicate that no charge transfer occurs between mol­ecules in the crystal; the compound should thus be considered a cocrystal rather than an organic complex. This is confirmed by the crystal structure, in which no significant stacking inter­actions are observed between mol­ecules. PMID:22589995

  2. Synthesis and gas adsorption properties of tetra-armed microporous organic polymer networks based on triphenylamine.

    PubMed

    Yang, Xiao; Yao, Shuwen; Yu, Miao; Jiang, Jia-Xing

    2014-04-01

    Two novel tetra-armed microporous organic polymers have been designed and synthesized via a nickel-catalyzed Yamamoto-type Ullmann cross-coupling reaction or Suzuki cross-coupling polycondensation. These polymers are stable in various solvents, including concentrated hydrochloric acid, and are thermally stable. The homocoupled polymer YPTPA shows much higher Brunauer-Emmet-Teller-specific surface area up to 1557 m(2) g(-1) than the copolymer SPTPA (544 m(2) g(-1)), and a high CO2 uptake ability of 3.03 mmol g(-1) (1.13 bar/273 K) with a CO2 /N2 sorption selectivity of 17.3:1. Both polymers show high isosteric heats of CO2 adsorption (22.7-26.5 kJ mol(-1)) because the incorporation of nitrogen atoms into the skeleton of microporous organic polymers enhances the interaction between the pore wall and the CO2 molecules. The values are higher than those of the porous aromatic frameworks, which contain neither additional polar functional groups nor nitrogen atoms, and are rather close to those of previously reported microporous organic polymers containing the nitrogen atoms on the pore wall. These data show that these materials would be potential candidates for applications in post-combustion CO2 capture and sequestration technology.

  3. Reversible Piezofluorochromic Property and Intrinsic Structure Changes of Tetra(4-methoxyphenyl)ethylene under High Pressure.

    PubMed

    Wu, Jinxia; Tang, Jia; Wang, Hailong; Qi, Qingkai; Fang, Xiaofeng; Liu, Yifei; Xu, Shuping; Zhang, Sean Xiao-An; Zhang, Houyu; Xu, Weiqing

    2015-09-01

    During the past decade, luminescent mechanochromism has received much attention. Despite the garnered attention, only a few studies have reported the effect of internal molecular structure change on the performance of mechanochromic fluorescence. Here, we chose tetra(4-methoxyphenyl)ethylene (TMOE) as a model molecule to study the correlation between structure and fluorescence property under a hydrostatic pressure produced by a diamond anvil cell (DAC). TMOE is a methoxy-substituted tetraphenylethylene (TPE) derivative and has a nearly centrosymmetric structure and a natural propeller shape. Ultraviolet-visible absorption and fluorescence spectra of TMOE and TPE in solution proved that the presence of methoxy groups in TMOE is responsible for the difference in fluorescence emissions of TMOE and TPE. Under a hydrostatic pressure, the in situ fluorescence spectra of TMOE at different concentrations show that the fluorescence intensity gradually weakens, accompanied by an obvious redshift. The Raman peak intensities decrease gradually, and the peaks disappear eventually with the pressure increasing. These spectral changes are attributed to the changes in the intramolecular conformation, that is, the strengthening of the weak C-H···O hydrogen bonds in TMOE molecules, which is caused by the twisted dihedral angle between the benzene ring and the carbon rigid plane of ethylene. Density functional theory simulation further confirms that the decreased dihedral angle could weaken Raman peak intensity, which is consistent with our experimental results. PMID:26262432

  4. A Tb–Zn tetra(4-sulfonatophenyl)porphyrin hybrid: Preparation, structure, photophysical and electrochemical properties

    SciTech Connect

    Chen, Wen-Tong; Hu, Rong-Hua; Wang, Yin-Feng; Zhang, Xian; Liu, Juan

    2014-05-01

    A terbium-zinc porphyrin, i.e. [TbZn(TPPS)H{sub 3}O]{sub n} (1) (TPPS=tetra(4-sulfonatophenyl)porphyrin), has been obtained from a solvothermal reaction and structurally analyzed by single-crystal X-ray diffraction. Compound 1 is characteristic of a condensed three-dimensional (3-D) porous open framework with two types of infinite one-dimensional (1-D) chain-like structure. Compound 1 exhibits a void space of 215 Å{sup 3}, which is 9.2% of the unit-cell volume. TG/DTA measurement reveals that the framework of compound 1 is thermally stable up to 336 °C. In order to reveal its photophysical and electrochemical properties, we investigated compound 1 in detail with UV–vis spectra, fluorescence, quantum yield, luminescence lifetime, and CV/DPV. - Graphical abstract: A terbium–zinc porphyrin [TbZn(TPPS)H{sub 3}O]{sub n} has been obtained from a solvothermal reaction. It features a condensed 3-D porous open framework. It shows good thermal stability. - Highlights: • This paper reports a novel terbium–zinc porphyrin. • It features a novel condensed three-dimensional porous open framework. • The title compound is thermally stable up to 336 °C. • It is studied by UV–vis, fluorescence, quantum yield, lifetime, and CV/DPV.

  5. Crystal structure of tetra­aqua­(di­methyl­formamide)­tetra­kis­(μ-N,2-dioxido­benzene-1-carboximidato)tetra­kis­(μ-tri­methyl­acetato)­tetra­manganese(III)sodiumyttrium–di­methyl­formamide–water (1/8.04/0.62)

    PubMed Central

    Travis, Jordan R.; Zeller, Matthias; Zaleski, Curtis M.

    2015-01-01

    The synthesis and crystal structure for the title compound, [YNaMn4(C7H4NO3)4(C5H9O2)4(H2O)3.76(C3H7NO)0.24]·8.04C3H7NO·0.62H2O or [YIIINa(OTMA)4[12-MCMn(III)N(shi)-4](H2O)3.76(DMF)0.24·8.04DMF·0.62H2O, where OTMA is tri­methyl­acetate, MC is metallacrown, shi3− is salicyl­hydroximate, and DMF is N,N-di­methyl­formamide, is reported. The macrocyclic metallacrown consists of an –[MnIII–N–O]4– ring repeat unit, and the metallacrown captures one YIII ion and one NaI ion in the central cavity on opposite faces of the metallacrown. Overall the metallacrown is domed towards the side of the NaI ion. Both the YIII and NaI ions are eight-coordinate, and the tri­methyl­acetate anions bridge the central YIII to each ring MnIII ion. The ring MnIII ions are six-coordinate with a tetra­gonally distorted octa­hedral geometry. PMID:26594496

  6. Synthesis of tetra- and octa-aurated heteroaryl complexes towards probing aromatic indoliums

    PubMed Central

    Yuan, Jun; Sun, Tingting; He, Xin; An, Ke; Zhu, Jun; Zhao, Liang

    2016-01-01

    Polymetalated aromatic compounds are particularly challenging synthetic goals because of the limited thermodynamic stability of polyanionic species arising from strong electrostatic repulsion between adjacent carbanionic sites. Here we describe a facile synthesis of two polyaurated complexes including a tetra-aurated indole and an octa-aurated benzodipyrrole. The imido trinuclear gold(I) moiety exhibits nucleophilicity and undergoes an intramolecular attack on a gold(I)-activated ethynyl to generate polyanionic heteroaryl species. Their computed magnetic properties reveal the aromatic character in the five-membered ring. The incorporation of the aurated substituents at the nitrogen atom can convert non-aromaticity in the parent indolium into aromaticity in the aurated one because of hyperconjugation. Thus, the concept of hyperconjugative aromaticity is extended to heterocycles with transition metal substituents. More importantly, further analysis indicates that the aurated substituents can perform better than traditional main-group substituents. This work highlights the difference in aromaticity between polymetalated aryls and their organic prototypes. PMID:27186982

  7. Surface Plasmon Resonance Sensor Based on Ethylene Tetra-Fluoro-Ethylene Hollow Fiber.

    PubMed

    Chen, Pan; He, Yu-Jing; Zhu, Xiao-Song; Shi, Yi-Wei

    2015-01-01

    A new kind of hollow fiber surface plasmon resonance sensor (HF-SPRS) based on the silver-coated ethylene tetra-fluoro-ethylene (ETFE) hollow fiber (HF) is presented. The ETFE HF-SPRS is fabricated, and its performance is investigated experimentally by measuring the transmission spectra of the sensor when filled by liquid sensed media with different refractive indices (RIs). Theoretical analysis based on the ray transmission model is also taken to evaluate the sensor. Because the RI of ETFE is much lower than that of fused silica (FSG), the ETFE HF-SPRS can extend the lower limit of the detection range of the early reported FSG HF-SPRS from 1.5 to 1.42 approximately. This could greatly enhance the application potential of HF-SPRS. Moreover, the joint use of both ETFE and FSG HF-SPRSs can cover a wide detection range from 1.42 to 1.69 approximately with high sensitivities larger than 1000 nm/RIU. PMID:26540062

  8. Antitumor polycyclic acridines. 7. Synthesis and biological properties of DNA affinic tetra- and pentacyclic acridines.

    PubMed

    Stanslas, J; Hagan, D J; Ellis, M J; Turner, C; Carmichael, J; Ward, W; Hammonds, T R; Stevens, M F

    2000-04-20

    New synthetic routes to a series of tetra- and pentacyclic acridines related in structure to marine natural products are reported. The novel water-soluble agent dihydroindolizino[7,6,5-kl]acridinium chloride 14 has inhibitory activity in a panel of non-small-cell lung and breast tumor cell lines exceeding that of m-AMSA. The salt inhibited the release of minicircle products of kDNA confirming that disorganization of topoisomerase II partly underlies the activity of the compound. COMPARE analysis of the NCI mean graph profile of compound 14 at the GI(50) level corroborates this conclusion with Pearson correlation coefficients (>0.6) to clinical agents of the topoisomerase II class: however, this correlation was not seen at the LC(50) level. The inhibitory action of 14 on Saccharomyces cerevisiae transfected with human topoisomerase II isoforms showed a 3-fold selectivity against the IIalpha isoform over the IIbeta isoform. Unlike m-AMSA, 14 is not susceptible to P-glycoprotein-mediated drug efflux and retains activity in lung cells with derived resistance to the topoisomerase II inhibitor etoposide.

  9. DNA Barcodes of Rosy Tetras and Allied Species (Characiformes: Characidae: Hyphessobrycon) from the Brazilian Amazon Basin

    PubMed Central

    Castro Paz, Francis Paola; Batista, Jacqueline da Silva; Porto, Jorge Ivan Rebelo

    2014-01-01

    DNA barcoding can be an effective tool for fast and accurate species-level identification based on sequencing of the mitochondrial cytochrome c oxidase subunit (COI) gene. The diversity of this fragment can be used to estimate the richness of the respective species. In this study, we explored the use of DNA barcoding in a group of ornamental freshwater fish of the genus Hyphessobrycon. We sequenced the COI from 10 species of Hyphessobrycon belonging to the “Rosy Tetra Clade” collected from the Amazon and Negro River basins and combined our results with published data. The average conspecific and congeneric Kimura 2-parameter distances were 2.3% and 19.3%, respectively. Six of the 10 species were easily distinguishable by DNA barcoding (H. bentosi, H. copelandi, H. eques, H. epicharis, H. pulchrippinis, and H. sweglesi), whereas the remaining species (H. erythrostigma, H. pyrrhonotus, H. rosaceus and H. socolofi) lacked reciprocal monophyly. Although the COI gene was not fully diagnostic, the discovery of distinct evolutionary units in certain Hyphessobrycon species under the same specific epithet as well as haplotype sharing between different species suggest that DNA barcoding is useful for species identification in this speciose genus. PMID:24878569

  10. Crystal structure of borated N,N,N′,N′-tetra­methyldi­amino­methane

    PubMed Central

    Louven, Kathrin; Quentin, Georgina; Strohmann, Carsten

    2015-01-01

    In the title compound, {[(di­methyl­amino)­meth­yl]di­methyl­amine}­trihydridoboron, C5H17BN2, the tetra­hedral geometry of the N—C—N unit is slightly disorted. As a result of the bulky amine substituents, a wider N—C—N angle of 113.6 (1)° is observed. The bond lengths between the N atom and methyl groups are slighly elongated to 1.481 (2) and 1.482 (2) Å at the borated N atom, whereas the distances between the other N atom and its methyl groups are only 1.461 (2) and 1.462 (2) Å. The studied crystal was twinned. The twin data refinement was subsequently carried out with a scale factor of 0.263 (1). The two lattices of the twin domains were rotated by 179.84°. PMID:26594453

  11. DNA barcodes of Rosy Tetras and allied species (Characiformes: Characidae: Hyphessobrycon) from the Brazilian Amazon basin.

    PubMed

    Castro Paz, Francis Paola; Batista, Jacqueline da Silva; Porto, Jorge Ivan Rebelo

    2014-01-01

    DNA barcoding can be an effective tool for fast and accurate species-level identification based on sequencing of the mitochondrial cytochrome c oxidase subunit (COI) gene. The diversity of this fragment can be used to estimate the richness of the respective species. In this study, we explored the use of DNA barcoding in a group of ornamental freshwater fish of the genus Hyphessobrycon. We sequenced the COI from 10 species of Hyphessobrycon belonging to the "Rosy Tetra Clade" collected from the Amazon and Negro River basins and combined our results with published data. The average conspecific and congeneric Kimura 2-parameter distances were 2.3% and 19.3%, respectively. Six of the 10 species were easily distinguishable by DNA barcoding (H. bentosi, H. copelandi, H. eques, H. epicharis, H. pulchrippinis, and H. sweglesi), whereas the remaining species (H. erythrostigma, H. pyrrhonotus, H. rosaceus and H. socolofi) lacked reciprocal monophyly. Although the COI gene was not fully diagnostic, the discovery of distinct evolutionary units in certain Hyphessobrycon species under the same specific epithet as well as haplotype sharing between different species suggest that DNA barcoding is useful for species identification in this speciose genus.

  12. Surface Plasmon Resonance Sensor Based on Ethylene Tetra-Fluoro-Ethylene Hollow Fiber

    PubMed Central

    Chen, Pan; He, Yu-Jing; Zhu, Xiao-Song; Shi, Yi-Wei

    2015-01-01

    A new kind of hollow fiber surface plasmon resonance sensor (HF-SPRS) based on the silver-coated ethylene tetra-fluoro-ethylene (ETFE) hollow fiber (HF) is presented. The ETFE HF-SPRS is fabricated, and its performance is investigated experimentally by measuring the transmission spectra of the sensor when filled by liquid sensed media with different refractive indices (RIs). Theoretical analysis based on the ray transmission model is also taken to evaluate the sensor. Because the RI of ETFE is much lower than that of fused silica (FSG), the ETFE HF-SPRS can extend the lower limit of the detection range of the early reported FSG HF-SPRS from 1.5 to 1.42 approximately. This could greatly enhance the application potential of HF-SPRS. Moreover, the joint use of both ETFE and FSG HF-SPRSs can cover a wide detection range from 1.42 to 1.69 approximately with high sensitivities larger than 1000 nm/RIU. PMID:26540062

  13. Toxic equivalency factors for tetra- through octachlorinated dibenzofurans in PLHC-1 fish hepatoma cell line

    SciTech Connect

    Tysklind, M.; Rappe, C.; Tillift, D.E.; Eriksson, L.

    1995-12-31

    Planar halogenated hydrocarbons (PHHs) elicit dioxin-like effects in fish at extremely low doses. However, the relative potencies of PHHs in fish differ from mammals in both absolute magnitude and relative rank order. Therefore, the relative potencies of polychlorinated dibenzofurans (PCDFs) were examined in PLHC-1 fish hepatoma cells. The response of PHHs in this cell line correlates with their toxicity to cause early life stage toxicity in fish. Twenty PCDFs were selected by means of a multivariate chemical characterization in combination with a 2{sup 4}-factorial design and separated into a 10 congener training set and 10 congener validation set. Toxic equivalency factors (TEFs) were determined for all 20 PCDF congeners based on ethoxyresorufin-O-deethylase (EROD) induction in the PLHC-1 cells. A quantitative structure-activity relation-ship (QSAR) model was constructed by partial least square modelling (PLS) of the physiochemical descriptor variables for the PCDFs in the training set and their EROD responses in the PLHC-1 cells. A predictive model was developed which accurately assessed the TEFs of the validation set of PCDFs. The model accounted for 87% (R{sup 2}) of the variance in TEFs and a cross-validated variance (Q{sup 2}) of 79%. From this QSAR, TEF values were predicted for all of the tetra through octa-chlorinated PCDFs in fish. Interestingly, there was a high degree of correlation among TEF values calculated in the PLHC-1 cells and the TEF values calculated in H411 E rat hepatoma cells.

  14. Electrocatalytic Oxygen Reduction by Iron Tetra-arylporphyrins Bearing Pendant Proton Relays

    SciTech Connect

    Carver, Colin T.; Matson, Benjamin D.; Mayer, James M.

    2012-03-28

    Fe(III)meso-tetra(2-carboxyphenyl)porphine chloride (1) was investigated as an electrocatalyst for the oxygen reduction reaction (ORR). Rotating ring-disk voltammetry and independent reactions with hydrogen peroxide indicate that 1 has very high selectivity for reduction of O2 to H2O, without forming significant amounts of H2O2. Cyclic voltammetric measurements at high substrate/catalyst ratios allowed the determination of the turnover frequency (TOF) of 1, TOF = 103 s-1. The 4-carboxyphenyl isomer of 1, in which the carboxylic acids point away from the iron center, is a substantially slower and less selective catalyst. This direct comparison demonstrates that the value of the carboxylate groups positioned to act as proton delivery relays to enhance both the TOF and selectivity of 1 as a catalyst for the ORR. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

  15. Dichlorido(3-phenyl-indenyl-idene)bis-(triphenyl-phosphane)ruthenium(II) tetra-hydro-furan disolvate.

    PubMed

    Bats, Jan W; Pérez Gomes, Jessica; Doppiu, Angelino; Hashmi, A Stephen K

    2011-06-01

    The Ru(II) atom in the title compound, [RuCl(2)(C(15)H(10))(C(18)H(15)P)(2)]·2C(4)H(8)O, has a distorted square-pyramidal conformation. The P and Cl atoms are at the base of the pyramid and the Ru-C(indenyl-idene) bond is in the axial position. The two Cl ligands and the two phosphane ligands are in trans positions. The Cl-Ru-Cl and P-Ru-P angles are 157.71 (2) and 166.83 (2)°, respectively. The two independent tetra-hydro-furan (THF) solvent mol-ecules are disordered. One THF mol-ecule was refined using a split-atom model. The second THF mol-ecule was accounted for by using program PLATON/SQUEEZE [Spek (2009 ▶). Acta Cryst. D65, 148-155]. The molecular conformation shows three intramolecular C-H⋯Cl contacts and two C-H⋯π interactions while the crystal packing features an intermolecular C-H⋯Cl contact and two very weak intermolecular C-H⋯π contacts. PMID:21754621

  16. TETRA observation of gamma-rays at ground level associated with nearby thunderstorms

    PubMed Central

    Ringuette, Rebecca; Case, Gary L; Cherry, Michael L; Granger, Douglas; Guzik, T Gregory; Stewart, Michael; Wefel, John P

    2013-01-01

    [1] Terrestrial gamma-ray flashes (TGFs)—very short, intense bursts of electrons, positrons, and energetic photons originating from terrestrial thunderstorms—have been detected with satellite instruments. TGF and Energetic Thunderstorm Rooftop Array (TETRA), an array of NaI(Tl) scintillators at Louisiana State University, has now been used to detect similar bursts of 50 keV to over 2 MeV gamma-rays at ground level. After 2.6 years of observation, 24 events with durations 0.02–4.2 ms have been detected associated with nearby lightning, three of them coincident events observed by detectors separated by ∼1000 m. Nine of the events occurred within 6 ms and 5 km of negative polarity cloud-to-ground lightning strokes with measured currents in excess of 20 kA. The events reported here constitute the first catalog of TGFs observed at ground level in close proximity to the acceleration site. PMID:26167428

  17. Spectroscopic studies of the interaction between tetra-substituted aluminum phthalocyanines and bovine serum albumin

    NASA Astrophysics Data System (ADS)

    He, Yipeng; Zheng, Liqin; Huang, Yide; Lin, Pingping; Yang, Hongqin; Peng, Yiru

    2014-11-01

    Serum albumin, the most abundant plasma protein in mammalian blood, shows significant effects on delivery and therapeutic efficacy of drugs, therefore, the investigation of binding interaction between serum albumin and drugs is vital and necessary. In the present study, the binding interaction of two aluminum (III) phthalocyanine (AlPc) derivatives, tetrasulfonate- and tetra-(p-sulfoazophenyl-4-aminosulfonyl)-substituted AlPc (complexes 1 and 2), with bovine serum albumin (BSA) was investigated by UV-Vis and fluorescence spectroscopy. Adding BSA to the Pc complexes in water caused remarkable changes in the Q-band of the Pc complexes, indicating an altered aggregation behavior. When titrating these AlPcs with BSA in PBS, the intrinsic fluorescence of BSA was significantly quenched through a static quenching process. The binding of Pc complexes to BSA might change its conformation, evidenced by the red shift of maximum emission wavelength. Furthermore, binding constants and binding sites were obtained and binding ability between the Pc complexes and BSA was assessed. Our results suggest that complexes 1 and 2 readily interact with BSA whereas the latter shows more affinity (with higher binding constant value) to BSA, implying the stretched amphiphilic substituents of complex 2 may contribute to their transportation in the blood.

  18. Local tetra patterns: a new feature descriptor for content-based image retrieval.

    PubMed

    Murala, Subrahmanyam; Maheshwari, R P; Balasubramanian, R

    2012-05-01

    In this paper, we propose a novel image indexing and retrieval algorithm using local tetra patterns (LTrPs) for content-based image retrieval (CBIR). The standard local binary pattern (LBP) and local ternary pattern (LTP) encode the relationship between the referenced pixel and its surrounding neighbors by computing gray-level difference. The proposed method encodes the relationship between the referenced pixel and its neighbors, based on the directions that are calculated using the first-order derivatives in vertical and horizontal directions. In addition, we propose a generic strategy to compute nth-order LTrP using (n - 1)th-order horizontal and vertical derivatives for efficient CBIR and analyze the effectiveness of our proposed algorithm by combining it with the Gabor transform. The performance of the proposed method is compared with the LBP, the local derivative patterns, and the LTP based on the results obtained using benchmark image databases viz., Corel 1000 database (DB1), Brodatz texture database (DB2), and MIT VisTex database (DB3). Performance analysis shows that the proposed method improves the retrieval result from 70.34%/44.9% to 75.9%/48.7% in terms of average precision/average recall on database DB1, and from 79.97% to 85.30% and 82.23% to 90.02% in terms of average retrieval rate on databases DB2 and DB3, respectively, as compared with the standard LBP.

  19. An oxalate selective electrode based on modified PVC-membrane with tetra-butylammonium--Clinoptilolite nanoparticles.

    PubMed

    Hoseini, Zohre; Nezamzadeh-Ejhieh, Alireza

    2016-03-01

    A modified PVC-membrane electrode with tetra-butylammonium bromide - Clinoptilolite nano-particles (TBA-NCP) showed good Nernstian slope (29.9±0.6 mV per decade of oxalate concentration) in concentration range of 3.1×10(-7)-8.3×10(-1) mol L(-1) with a detection limit of 1.5×10(-7) mol L(-1). The best performance was obtained with a membrane composition of 31.5% PVC, 62.5% DOP and 6% TBA-NCP in the temperature range of 20-35 °C and the pH range of 4-9. The fast response time and good reproducibility over a period of 3 months are other characteristics of the sensor. The proposed electrode was successfully used as an indicator electrode in titration of oxalate ions with CaCl2 solution. The proposed electrode was also used in direct potentiometric determination of oxalate in many real samples such as: mushroom, black and green tea, spinach and beet.

  20. Mol-ecular and crystal structure of gossypol tetra-methyl ether with an unknown solvate.

    PubMed

    Honkeldieva, Muhabbat; Talipov, Samat; Mardanov, Rustam; Ibragimov, Bakhtiyar

    2015-02-01

    The title compound, C34H38O8 (systematic name: 5,5'-diisopropyl-2,2',3,3'-tetra-meth-oxy-7,7'-dimethyl-2H,2'H-8,8'-bi-[naphtho-[1,8-bc]furan]-4,4'-diol), has been obtained from a gossypol solution in a mixture of dimethyl sulfate and methanol. The mol-ecule is situated on a twofold rotation axis, so the asymmetric unit contains one half-mol-ecule. In the mol-ecule, the hy-droxy groups are involved in intra-molecular O-H⋯O hydrogen bonds, and the two naphthyl fragments are inclined each to other by 83.8 (1)°. In the crystal, weak C-H⋯O and C-H⋯π inter-actions consolidate the packing, which exhibits channels with an approximate diameter of 6 Å extending along the c-axis direction. These channels are filled with highly disordered solvent mol-ecules, so their estimated scattering contribution was subtracted from the observed diffraction data using the SQUEEZE option in PLATON [Spek, A. L. (2015). Acta Cryst. C71, 9-18]. PMID:25878814

  1. Evaluation on the hydrolysis of methylumbelliferyl-tetra-N-acetylchitotetraoside by various glucosidases. A comparative study.

    PubMed

    Den Tandt, W R; Scharpe, S; Overdijk, B

    1993-01-01

    1. In human plasma, an enzyme is present which hydrolyzes 4-methylumbelliferyl-tetra-N-acetylchitotetraoside. The function of this enzyme is unknown. 2. We have examined whether hyaluronidase, neutral endoglucosaminidase, N-acetyl-beta-D-hexosaminidase, aspartylglucosaminidase, beta-D-glucosidase, and chitobiase could hydrolyze MU-TACT. The results obtained are detailed below. 3. A purified commercial preparation of hyaluronidase does not hydrolyze MU-TACT. 4. Substrate specificity requirements, pH optimum and subcellular localization indicate that neutral endoglucosaminidase is distinguishable from MU-TACT hydrolase. Also commercial neutral endoglucosaminidase D and H have no affinity towards MU-TACT. 5. N-Acetyl-beta-D-hexosaminidase is different from MU-TACT hydrolase for the following reasons: (a) a purified enzyme preparation does not hydrolyze MU-TACT; (b) there is no correlation in the activity of the enzymes; (c) MU-TACT hydrolase is not deficient in cells of a patient with a deficiency of total N-acetyl-beta-D-glucosaminidase; and (d) the 2 enzymes have very different chromatographic characteristics and Con A binding properties. 6. Enzyme characteristics, substrate structural requirements and a lack of correlation with MU-TACT hydrolase activity suggest that aspartylglucosaminidase, beta-D-glucosidase, and chitobiase are not involved in the hydrolysis of MU-TACT. 7. None of the enzymes which we have considered corresponds to MU-TACT hydrolase. The exact nature and the function of the enzyme remains an enigma. PMID:8432379

  2. Unifying Evaluation of the Technical Performances of Iron-Tetra-amido Macrocyclic Ligand Oxidation Catalysts.

    PubMed

    DeNardo, Matthew A; Mills, Matthew R; Ryabov, Alexander D; Collins, Terrence J

    2016-03-01

    The main features of iron-tetra-amido macrocyclic ligand complex (a sub-branch of TAML) catalysis of peroxide oxidations are rationalized by a two-step mechanism: Fe(III) + H2O2 → Active catalyst (Ac) (kI), and Ac + Substrate (S) → Fe(III) + Product (kII). TAML activators also undergo inactivation under catalytic conditions: Ac → Inactive catalyst (ki). The recently developed relationship, ln(S0/S∞) = (kII/ki)[Fe(III)]tot, where S0 and S∞ are [S] at time t = 0 and ∞, respectively, gives access to ki under any conditions. Analysis of the rate constants kI, kII, and ki at the environmentally significant pH of 7 for a broad series of TAML activators has revealed a 6 orders of magnitude reactivity differential in both kII and ki and 3 orders differential in kI. Linear free energy relationships linking kII with ki and kI reveal that the reactivity toward substrates is related to the instability of the active TAML intermediates and suggest that the reactivity in all three processes derives from a common electronic origin. The reactivities of TAML activators and the horseradish peroxidase enzyme are critically compared. PMID:26886296

  3. In vitro exposure of DE-71, a penta-PBDE mixture, on immune endpoints in bottlenose dolphins (Tursiops truncatus) and B6C3F1 mice.

    PubMed

    Wirth, Jena R; Peden-Adams, Margie M; White, Natasha D; Bossart, Gregory D; Fair, Patricia A

    2015-02-01

    Polybrominated diphenyl ethers (PBDEs) are an emerging contaminant of concern with low level exposures demonstrating toxicity in laboratory animals and wildlife, although immunotoxicity studies have been limited. Bottlenose dolphin peripheral blood leukocytes (PBLs) and mouse splenocytes were exposed to environmentally relevant DE-71 (a penta-PBDE mixture) concentrations (0-50 µg ml(-1) ) in vitro. Natural killer (NK) cell activity and lymphocyte (B and T cell) proliferation were evaluated using the parallelogram approach for risk assessment. This study aimed to substantiate results from field studies with dolphins, assess the sensitivities between the mouse model and dolphins, and to evaluate risk using the parallelogram approach. In mouse cells, NK cell activity increased at in vitro doses 0.05, 0.5 and 25 µg DE-71 ml(-1) , whereas proliferation was not modulated. In dolphin cells, NK cell activity and lymphocyte proliferation was not altered after in vitro exposure. In vitro exposure of dolphin PBLs to DE-71 showed similar results to correlative field studies; NK cell activity in mice was more sensitive to in vitro exposure than dolphins, and the parallelogram approach showed correlation with all three endpoints to predict risk in bottlenose dolphins.

  4. Use of gadolinium diethylene triamine penta-acetic acid, as measured by ELISA, in the determination of glomerular filtration rates in cats.

    PubMed

    Sox, Erika M; Chiotti, Ruthanne; Goldstein, Richard E

    2010-10-01

    The goal of this study was to evaluate a commercially available assay for gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) for use in estimating glomerular filtration rate (GFR) in cats (Gd-DTPA GFR) with a wide range of GFRs. Eighteen adult cats (11 healthy and seven with chronic kidney disease) were included. Plasma concentrations of Gd-DTPA following intravenous injection were measured with an ELISA kit (FIT-GFR). Results for Gd-DTPA GFR were compared with simultaneously obtained values for plasma clearance of iohexol (iohexol GFR), plasma blood urea nitrogen (BUN) and creatinine concentrations. A negative correlation existed between iohexol GFR and plasma concentrations of BUN and creatinine. A positive correlation existed between Gd-DTPA GFR and iohexol GFR. There was no correlation between Gd-DTPA GFR and plasma concentrations of BUN and creatinine. In this study plasma clearance of Gd-DTPA assayed by FIT-GFR did not appear to provide a sufficiently accurate estimation of GFR in cats when compared with plasma clearance of iohexol, and plasma concentrations of BUN and creatinine. PMID:20724186

  5. Anticonvulsant activity of 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose isolated from leaves of Mangifera indica.

    PubMed

    Viswanatha, G L; Mohan, C G; Shylaja, H; Yuvaraj, H C; Sunil, V

    2013-07-01

    The present study was aimed to evaluate the anticonvulsant activity of 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (PGG) isolated from methanolic leaf extracts of Mangifera indica in mice. Anticonvulsant activity of PGG was evaluated against pentylenetetrazole (PTZ)-induced and maximal electroshock (MES)-induced convulsions in mice. Additionally, locomotor activity and GABA levels in the brain were estimated to explore the possible CNS-depressant activity and mechanism behind the anticonvulsant activity, respectively. In these studies, PGG (2.5, 5, and 10 mg/kg, intraperitoneal (i.p.)) showed significant and dose-dependent inhibition of PTZ and MES-induced convulsions. Furthermore, PGG administration showed significant decrease in the locomotor activity as an indication of its CNS-depressant property; also, PGG has significantly increased the GABA levels in the cerebellum and whole brain other than the cerebellum. In conclusion, PGG isolated from M. indica showed potent anticonvulsant activity, and possible mechanism may be due to enhanced GABA levels in the brain.

  6. 1,2,3,4,6-Penta-O-galloyl-beta-D-glucose reduces renal crystallization and oxidative stress in a hyperoxaluric rat model.

    PubMed

    Lee, Hyo-Jung; Jeong, Soo-Jin; Lee, Hyo-Jeong; Lee, Eun-Ok; Bae, Hyunsu; Lieske, John C; Kim, Sung-Hoon

    2011-03-01

    Adhesion of calcium oxalate (CaOx) crystals to kidney cells may be a key event in the pathogenesis of kidney stones associated with marked hyperoxaluria. Previously, we found that 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), isolated from a traditional medicinal herb, reduced CaOx crystal adhesion to renal epithelial cells by acting on the cells as well as on the crystal surface. Here we used the ethylene glycol (EG)-mediated hyperoxaluric rat model and found evidence of oxidant stress as indicated by decreases in the activities of the renal antioxidant enzymes, superoxide dismutase, catalase, and glutathione peroxidase, with increased kidney cell apoptosis and serum malondialdehyde levels, all evident by 21 days of EG treatment. These effects of hyperoxaluria were reversed by concurrent PGG treatment along with decreased urinary oxalate levels and CaOx supersaturation. Renal epithelial cell expression of the crystal binding molecule hyaluronan increased diffusely within 7 days of EG initiation, suggesting it is not a result of but precedes crystal deposition. Renal cell osteopontin (OPN) was also upregulated in EG-treated animals, and PGG significantly attenuated overexpression of both OPN and hyaluronan. Thus, our findings demonstrate that PGG reduces renal crystallization and oxidative renal cell injury, and may be a candidate chemopreventive agent for nephrolithiasis.

  7. Inhibitory effects of 1,2,3,4,6-penta-O-galloyl-beta-D-glucopyranose on biofilm formation by Staphylococcus aureus.

    PubMed

    Lin, Mei-Hui; Chang, Fang-Rong; Hua, Mu-Yi; Wu, Yang-Chang; Liu, Shih-Tung

    2011-03-01

    1,2,3,4,6-Penta-O-galloyl-β-D-glucopyranose (PGG) is an active ingredient in plants that are commonly used in Chinese medicine to treat inflammation. We demonstrate here that PGG, at 6.25 μM, does not inhibit the growth of Staphylococcus aureus, and yet it prevents biofilm formation on polystyrene and polycarbonate surfaces. At the same concentration, PGG is not toxic to human epithelial and fibroblast cells. PGG has an IB₅₀ value, i.e., the PGG concentration that inhibits 50% biofilm formation, of 3.6 μM. The value is substantially lower than that of N-acetylcysteine, iodoacetamide, and N-phenyl maleimide, which are known to inhibit biofilm formation by S. aureus. Biochemical and scanning electron microscopy results also reveal that PGG inhibits initial attachment of the bacteria to solid surface and the synthesis of polysaccharide intercellular adhesin, explaining how PGG inhibits biofilm formation. The results of this study demonstrate that coating PGG on polystyrene and silicon rubber surfaces with polyaniline prevents biofilm formation, indicating that PGG is highly promising for clinical use in preventing biofilm formation by S. aureus.

  8. 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) reduces renal crystallization and oxidative stress in a hyperoxaluric rat model

    PubMed Central

    Lee, Hyo-Jung; Jeong, Soo-Jin; Lee, Hyo-Jeong; Lieske, John C.; Kim, Sung-Hoon

    2014-01-01

    Adhesion of calcium oxalate (CaOx) crystals to kidney cells may be a key event in the pathogenesis of kidney stones associated with marked hyperoxaluria. Previously, we found that 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG), isolated from a traditional medicinal herb, reduced CaOx crystal adhesion to renal epithelial cells by acting on the cells as well as the crystal surface. Here we used the ethylene glycol (EG) - mediated hyperoxaluric rat model and found evidence of oxidant stress as indicated by decreases in the activities of the renal antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase, with increased kidney cell apoptosis and serum malondialdehyde levels, all evident by 21 days of EG treatment. These effects of hyperoxaluria were reversed by concurrent PGG treatment along with decreased urinary oxalate levels and CaOx supersaturation. Renal epithelial cell expression of the crystal binding molecule hyaluronan increased diffusely within 7 days of EG initiation, suggesting it is not a result of but precedes crystal deposition. Renal cell osteopontin (OPN) was also up regulated in EG-treated animals, and PGG significantly attenuated over expression of both OPN and hyaluronan. Thus, our findings demonstrate that PGG reduces renal crystallization and oxidative renal cell injury, and may be a candidate chemo preventative agent for nephrolithiasis. PMID:21085110

  9. Structural analysis of the complex between penta-EF-hand ALG-2 protein and Sec31A peptide reveals a novel target recognition mechanism of ALG-2.

    PubMed

    Takahashi, Takeshi; Kojima, Kyosuke; Zhang, Wei; Sasaki, Kanae; Ito, Masaru; Suzuki, Hironori; Kawasaki, Masato; Wakatsuki, Soichi; Takahara, Terunao; Shibata, Hideki; Maki, Masatoshi

    2015-01-01

    ALG-2, a 22-kDa penta-EF-hand protein, is involved in cell death, signal transduction, membrane trafficking, etc., by interacting with various proteins in mammalian cells in a Ca2+-dependent manner. Most known ALG-2-interacting proteins contain proline-rich regions in which either PPYPXnYP (type 1 motif) or PXPGF (type 2 motif) is commonly found. Previous X-ray crystal structural analysis of the complex between ALG-2 and an ALIX peptide revealed that the peptide binds to the two hydrophobic pockets. In the present study, we resolved the crystal structure of the complex between ALG-2 and a peptide of Sec31A (outer shell component of coat complex II, COPII; containing the type 2 motif) and found that the peptide binds to the third hydrophobic pocket (Pocket 3). While amino acid substitution of Phe85, a Pocket 3 residue, with Ala abrogated the interaction with Sec31A, it did not affect the interaction with ALIX. On the other hand, amino acid substitution of Tyr180, a Pocket 1 residue, with Ala caused loss of binding to ALIX, but maintained binding to Sec31A. We conclude that ALG-2 recognizes two types of motifs at different hydrophobic surfaces. Furthermore, based on the results of serial mutational analysis of the ALG-2-binding sites in Sec31A, the type 2 motif was newly defined. PMID:25667979

  10. Molecular structure, vibrational spectra, HOMO, LUMO and NMR studies of 2,3,4,5,6-penta bromo toluene and bromo durene based on density functional calculations.

    PubMed

    Krishna Kumar, V; Suganya, S; Mathammal, R

    2014-05-01

    This work deals with the vibrational spectra of 2,3,4,5,6-Penta Bromo Toluene (PBT) and Bromo Durene (BD) by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis based on density functional theory (DFT) using B3LYP/6-31G* level and basis set combinations and was scaled using various scale factors yielding a good agreement between observed and calculated frequencies. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. The HOMO and LUMO energies were calculated within the molecule. (13)C and (1)H NMR chemical shifts results were also calculated and compared with the experimental values. Thermodynamical properties like entropy heat capacity, zero point energy have been calculated for the title molecules.

  11. Apoptosis induced by penta-acetyl geniposide in C6 glioma cells is associated with JNK activation and Fas ligand induction

    SciTech Connect

    Peng, C.-H.; Tseng, T.-H.; Huang, C.-N.; Hsu, S.-P.; Wang, C.-J. . E-mail: wcj@csmu.edu.tw

    2005-01-15

    In our previous study, penta-acetyl geniposide ((AC){sub 5}GP) is suggested to induce tumor cell apoptosis through the specific activation of PKC{delta}. However, the downstream signal pathway of PKC{delta} has not yet been investigated. It was shown that JNK may play an important role in the regulation of apoptosis and could be a possible downstream signal of PKC{delta} isoforms. In the present study, we investigate whether JNK is involved in (AC){sub 5}GP induced apoptosis. The result reveals that (AC){sub 5}GP induces JNK activation and c-Jun phosphorylation thus stimulating the expression of Fas-L and Fas. Using SP600125 to block JNK activation shows that (AC){sub 5}GP-mediated apoptosis and related proteins expression are attenuated. Furthermore, we find that the (AC){sub 5}GP induces apoptosis through the activation of JNK/Jun/Fas L/Fas/caspase 8/caspase 3, a mitochondria-independent pathway. The JNK pathway is suggested to be the downstream signal of PKC{delta}, since rottlerin impedes (AC){sub 5}GP-induced JNK activation. Therefore, (AC){sub 5}GP mediates cell death via activation of PKC{delta}/JNK/FasL cascade signaling.

  12. Structural analysis of the complex between penta-EF-hand ALG-2 protein and Sec31A peptide reveals a novel target recognition mechanism of ALG-2.

    PubMed

    Takahashi, Takeshi; Kojima, Kyosuke; Zhang, Wei; Sasaki, Kanae; Ito, Masaru; Suzuki, Hironori; Kawasaki, Masato; Wakatsuki, Soichi; Takahara, Terunao; Shibata, Hideki; Maki, Masatoshi

    2015-02-06

    ALG-2, a 22-kDa penta-EF-hand protein, is involved in cell death, signal transduction, membrane trafficking, etc., by interacting with various proteins in mammalian cells in a Ca2+-dependent manner. Most known ALG-2-interacting proteins contain proline-rich regions in which either PPYPXnYP (type 1 motif) or PXPGF (type 2 motif) is commonly found. Previous X-ray crystal structural analysis of the complex between ALG-2 and an ALIX peptide revealed that the peptide binds to the two hydrophobic pockets. In the present study, we resolved the crystal structure of the complex between ALG-2 and a peptide of Sec31A (outer shell component of coat complex II, COPII; containing the type 2 motif) and found that the peptide binds to the third hydrophobic pocket (Pocket 3). While amino acid substitution of Phe85, a Pocket 3 residue, with Ala abrogated the interaction with Sec31A, it did not affect the interaction with ALIX. On the other hand, amino acid substitution of Tyr180, a Pocket 1 residue, with Ala caused loss of binding to ALIX, but maintained binding to Sec31A. We conclude that ALG-2 recognizes two types of motifs at different hydrophobic surfaces. Furthermore, based on the results of serial mutational analysis of the ALG-2-binding sites in Sec31A, the type 2 motif was newly defined.

  13. In vitro exposure of DE-71, a penta-PBDE mixture, on immune endpoints in bottlenose dolphins (Tursiops truncatus) and B6C3F1 mice.

    PubMed

    Wirth, Jena R; Peden-Adams, Margie M; White, Natasha D; Bossart, Gregory D; Fair, Patricia A

    2015-02-01

    Polybrominated diphenyl ethers (PBDEs) are an emerging contaminant of concern with low level exposures demonstrating toxicity in laboratory animals and wildlife, although immunotoxicity studies have been limited. Bottlenose dolphin peripheral blood leukocytes (PBLs) and mouse splenocytes were exposed to environmentally relevant DE-71 (a penta-PBDE mixture) concentrations (0-50 µg ml(-1) ) in vitro. Natural killer (NK) cell activity and lymphocyte (B and T cell) proliferation were evaluated using the parallelogram approach for risk assessment. This study aimed to substantiate results from field studies with dolphins, assess the sensitivities between the mouse model and dolphins, and to evaluate risk using the parallelogram approach. In mouse cells, NK cell activity increased at in vitro doses 0.05, 0.5 and 25 µg DE-71 ml(-1) , whereas proliferation was not modulated. In dolphin cells, NK cell activity and lymphocyte proliferation was not altered after in vitro exposure. In vitro exposure of dolphin PBLs to DE-71 showed similar results to correlative field studies; NK cell activity in mice was more sensitive to in vitro exposure than dolphins, and the parallelogram approach showed correlation with all three endpoints to predict risk in bottlenose dolphins. PMID:24706408

  14. Chloridotris(penta­fluoro­benzene­thiol­ato-κS)[tris­(4-fluoro­phen­yl)phosphine-κP]osmium(IV)

    PubMed Central

    Arias, Asdrúbal; Meléndez, Lidia; Bernès, Sylvain; Arroyo, Maribel

    2010-01-01

    The title complex, [Os(C6F5S)3Cl(C18H12F3P)], displays a trigonal-bipyramidal OsIV coordination geometry with the S atoms of three thiol­ate ligands occupying the equatorial positions. The thiol­ate penta­fluoro­phenyl substituents are all placed above the equatorial plane, forming a claw-like cavity which accommodates the chloride ligand with a normal Os—Cl bond length. The phosphine ligand trans to the chloride ligand reveals a short Os—P bond length compared to other chloride–phosphine OsIV complexes (average = 2.40 Å). This strong bonding indicates that the inductive effect of the F atoms in the phosphine does not affect significantly its basicity, compared to triphenyl­phosphine. This feature is also consistent with the known poor trans influence of Cl−. The crystal packing involves π–π contacts between inversion-related thiol­ate C6F5 rings, with a centroid–centroid separation of 3.659 (8) Å. PMID:21580558

  15. Synthesis, spectroscopic studies and crystal structure of the Schiff base ligand L derived from condensation of 2-thiophenecarboxaldehyde and 3,3'-diaminobenzidine and its complexes with Co(II), Ni(II), Cu(II), Cd(II) and Hg(II): Comparative DNA binding studies of L and its Co(II), Ni(II) and Cu(II) complexes

    NASA Astrophysics Data System (ADS)

    Shakir, Mohammad; Abbasi, Ambreen; Azam, Mohammad; Khan, Asad U.

    2011-09-01

    The Schiff base ligand, N,N'-bis-(2-thiophenecarboxaldimine)-3,3'-diaminobenzidine (L) obtained from condensation of 2-thiophenecarboxaldehyde and 3,3'-diaminobenzidine, was used to synthesize the complexes of type, [M 2L 2]Cl 4 [M = Co(II), Ni(II), Cu(II), Cd(II) and Hg(II)]. The newly synthesized ligand (L) was characterized on the basis of the results of elemental analysis, FT-IR, 1H NMR, 13C NMR, mass spectroscopic studies and single crystal X-ray crystallography. The characteristic resonance signals in 1H NMR and 13C NMR spectra indicated the presence of azomethine group as a result of condensation reaction. The stoichiometry, bonding and stereochemistries of complexes were ascertained on the basis of results of elemental analysis, magnetic susceptibility measurements, molar conductance and spectroscopic studies viz., FT-IR, 1H and 13C NMR, UV-vis and EPR. EPR, UV-vis and magnetic moment data revealed an octahedral geometry for complexes with distortion in Cu(II) complex and conductivity data show 1:2 electrolytic nature of complexes. Absoption and fluorescence spectroscopic studies supported that Schiff base ligand L and its Co(II), Ni(II) and Cu(II) complexes exhibited significant binding to calf thymus DNA. The complexes exhibited higher affinity to calf thymus DNA than the free Schiff base ligand L.

  16. Chloridotris[μ2-2-(dimethyl­amino)­ethano­lato]-μ3-hydroxido-tri-μ2-trifluoro­acetato-tetra­copper(II) tetra­hydro­furan solvate

    PubMed Central

    Hussain, S. Tajammul; Bakar, Shahzad Abu; Mazhar, Mohammad; Zeller, Matthias

    2010-01-01

    The title compound, [Cu4(C2F3O2)3(C4H10NO)3Cl(OH)]·C4H8O or [Cu4(TFA)3(dmae)3Cl(OH)]·THF (dmae is dimeth­yl­amino­ethano­late, TFA is trifluoro­acetate and THF is tetra­hydro­furan), has an approximate mol­ecular threefold symmetry with three equivalent {Cu(dmae)(TFA)} units bridging between a Cu—Cl and a hydroxide unit, with the latter two lying on the mol­ecular threefold axis. However, in the solid state, the tetranuclear complex has Ci symmetry. The Cu atom bonded to the Cl atom has a distorted tetra­hedral geometry. The other three Cu atoms have distorted square-pyramidal geometries with an NO4 coordination environment. The bonds within the CuNO3 base of the pyramid range from 1.953 (2) to 2.033 (3) Å, while the apical Cu—O bonds are significantly longer, ranging from 2.286 (2) to 2.377 (2) Å. The square-pyramidal geometries are augmented by weak inter­actions towards a sixth O atom, forming a highly distorted octa­hedral coordination environment [long Cu—O distances = 2.712 (2)–2.824 (2) Å]. The hydroxide group is hydrogen bonded to the tetra­hydro­furan solvent mol­ecule. One of the –CF3 groups shows minor disorder over two positions, with a refined occupancy ratio of 0.894 (4):0.106 (5). PMID:21587732

  17. Chloridotris[μ(2)-2-(dimethyl-amino)-ethano-lato]-μ(3)-hydroxido-tri-μ(2)-trifluoro-acetato-tetra-copper(II) tetra-hydro-furan solvate.

    PubMed

    Hussain, S Tajammul; Bakar, Shahzad Abu; Mazhar, Mohammad; Zeller, Matthias

    2010-01-01

    The title compound, [Cu(4)(C(2)F(3)O(2))(3)(C(4)H(10)NO)(3)Cl(OH)]·C(4)H(8)O or [Cu(4)(TFA)(3)(dmae)(3)Cl(OH)]·THF (dmae is dimeth-yl-amino-ethano-late, TFA is trifluoro-acetate and THF is tetra-hydro-furan), has an approximate mol-ecular threefold symmetry with three equivalent {Cu(dmae)(TFA)} units bridging between a Cu-Cl and a hydroxide unit, with the latter two lying on the mol-ecular threefold axis. However, in the solid state, the tetranuclear complex has C(i) symmetry. The Cu atom bonded to the Cl atom has a distorted tetra-hedral geometry. The other three Cu atoms have distorted square-pyramidal geometries with an NO(4) coordination environment. The bonds within the CuNO(3) base of the pyramid range from 1.953 (2) to 2.033 (3) Å, while the apical Cu-O bonds are significantly longer, ranging from 2.286 (2) to 2.377 (2) Å. The square-pyramidal geometries are augmented by weak inter-actions towards a sixth O atom, forming a highly distorted octa-hedral coordination environment [long Cu-O distances = 2.712 (2)-2.824 (2) Å]. The hydroxide group is hydrogen bonded to the tetra-hydro-furan solvent mol-ecule. One of the -CF(3) groups shows minor disorder over two positions, with a refined occupancy ratio of 0.894 (4):0.106 (5). PMID:21587732

  18. Intra- and inter-nucleosomal interactions of the histone H4 tail revealed with a human nucleosome core particle with genetically-incorporated H4 tetra-acetylation.

    PubMed

    Wakamori, Masatoshi; Fujii, Yoshifumi; Suka, Noriyuki; Shirouzu, Mikako; Sakamoto, Kensaku; Umehara, Takashi; Yokoyama, Shigeyuki

    2015-11-26

    Post-translational modifications (PTMs) of histones, such as lysine acetylation of the N-terminal tails, play crucial roles in controlling gene expression. Due to the difficulty in reconstituting site-specifically acetylated nucleosomes with crystallization quality, structural analyses of histone acetylation are currently performed using synthesized tail peptides. Through engineering of the genetic code, translation termination, and cell-free protein synthesis, we reconstituted human H4-mono- to tetra-acetylated nucleosome core particles (NCPs), and solved the crystal structures of the H4-K5/K8/K12/K16-tetra-acetylated NCP and unmodified NCP at 2.4 Å and 2.2 Å resolutions, respectively. The structure of the H4-tetra-acetylated NCP resembled that of the unmodified NCP, and the DNA wrapped the histone octamer as precisely as in the unmodified NCP. However, the B-factors were significantly increased for the peripheral DNAs near the N-terminal tail of the intra- or inter-nucleosomal H4. In contrast, the B-factors were negligibly affected by the H4 tetra-acetylation in histone core residues, including those composing the acidic patch, and at H4-R23, which interacts with the acidic patch of the neighboring NCP. The present study revealed that the H4 tetra-acetylation impairs NCP self-association by changing the interactions of the H4 tail with DNA, and is the first demonstration of crystallization quality NCPs reconstituted with genuine PTMs.

  19. Improved antimicrobial therapy with cationic tetra- and octa-substituted phthalocyanines

    NASA Astrophysics Data System (ADS)

    Angelov, I.; Mantareva, V.; Kussovski, V.; Woehrle, D.; Borisova, E.; Avramov, L.

    2008-12-01

    Photodynamic therapy (PDT) today is an innovative and not yet widespread light-drug initiated treatment that is based on the photoactive compound irradiated with proper light to produce oxygen species that are toxic to the pathogenic biological objects- bacteria, viruses, tumor cells. The obstacles that limited the efficacy of PDT concern to the selectivity and multi-drug resistance prolong time for cellular release and side effects of skin photosensitivity for commercial porphyrin originated photosensitizers (PS). Now there are very intensive investigations for introducing in practice a new, with a least side effects PSs for PDT. The usefulness of the more extended macromolecules structured with proper substituents refers not only to the improved optical properties like far-red and with intensive absorption and emission capacity, but mainly to the ability for selective delivery and adhesion to the target cells, such as bacteria or other pathogens. The present study focuses on the charge effect of photodynamic agent on the uptake capacity toward gram-negative bacteria cells and their further photoinactivation. The multi-drug resistant microorganism Aeromanas hydrophilla, which is causing diseases to fishes and humans, is treated. The new octa-cationic phthalocyanines are designed to compare PDT efficacy to the efficacy of tetra-substituted derivatives with the same functional peripheral substituents. The higher cellular accumulation to the bacteria cells as a result of the high number of positive charges of photosensitizer, leading to the better adhesion to the cellular membranes and improved photoinactivation of bacteria causing superficial and intraorgan infections. These results set a base of a rationale design of covalently octa-substituted phthalocyanines with positive charge for a successful treatment of microorganisms.

  20. Growth, spectroscopic and physicochemical properties of bis mercury ferric chloride tetra thiocyanate: A nonlinear optical crystal

    NASA Astrophysics Data System (ADS)

    Ramesh, V.; Shihabuddeen Syed, A.; Jagannathan, K.; Rajarajan, K.

    2013-05-01

    Single crystal of bis mercury ferric chloride tetra thiocyanate [Hg2FeCl3(SCN)4; (MFCTC)] was grown from ethanol-water (3:1) mixed solvent using slow evaporation solvent technique (SEST) for the first time. The cell parameters of the grown crystal were confirmed by single crystal XRD. The coordination of transition metal ions with the SCN ligand is well-identified using FT-IR spectral analysis. The chemical composition of MFCTC was confirmed using CHNS elemental test. The ESR spectral profile of MFCTC was recorded from 298 K to 110 K, which strongly suggests the incorporation of Fe3+ ion and its environment with respect to SCN ligand. The HPLC chromatogram of MFCTC highlights the purity of the compound. The UV-Vis-NIR studies revealed the ultra violet cut-off wavelength of MFCTC in ethanol as 338 nm. The dielectric constant and dielectric loss of the sample were studied as a function of frequency and temperature. The TGA-DTA and DSC thermal analysis show that the sample is thermally stable up to 234.31 °C, which is comparatively far better than the thermal stability of Hg3CdCl2(SCN)6; (171.3 °C) and other metal-organic coordination complex crystals such as CdHg(SCN)4 (198.5 °C), Hg(N2H4CS)4Mn(SCN)4 (199.06 °C) and Hg(N2H4CS)4Zn(SCN)4 (185 °C). The SHG conversion efficiency of MFCTC is found to be higher than KDP.

  1. Crystal structure of cis-di­chlorido­(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4 N)chromium(III) (oxalato-κ2 O 1,O 2)(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4 N)chromium(III) bis(perchlorate) from synchrotron data

    PubMed Central

    Moon, Dohyun; Choi, Jong-Ha

    2016-01-01

    In the asymmetric unit of the title compound, [CrCl2(C10H24N4)][Cr(C2O4)(C10H24N4)](ClO4)2 (C10H24N4 = 1,4,8,11-tetra­aza­cyclo­tetra­decane, cyclam; C2O4 = oxalate, ox), there are two independent halves of the [CrCl2(cyclam)]+ and [Cr(ox)(cyclam)]+ cations, and one perchlorate anion. In the complex cations, which are completed by application of twofold rotation symmetry, the CrIII ions are coordinated by the four N atoms of a cyclam ligand, and by two chloride ions or one oxalate bidentate ligand in a cis arrangement, displaying an overall distorted octa­hedral coordination environment. The Cr—N(cyclam) bond lengths are in the range of 2.075 (5) to 2.096 (4) Å while the Cr—Cl and Cr—O(ox) bond lengths are 2.3358 (14) and 1.956 (4) Å, respectively. Both cyclam moieties adopt the cis-V conformation. The slightly distorted tetra­hedral ClO4 − anion remains outside the coordination sphere. The supra­molecular architecture includes N—H⋯O and N—H⋯Cl hydrogen bonding between cyclam NH donor groups, O atoms of the oxalate ligand or ClO4 − anions and one Cl ligand as acceptors, leading to a three-dimensional network structure. PMID:27746932

  2. Microwave-assisted synthesis, characterization and spectral properties of non-peripherally tetra-substituted phthalocyanines containing eugenol moieties

    NASA Astrophysics Data System (ADS)

    Kantar, Cihan; Şahin, Zarife Sibel; Büyükgüngör, Orhan; Şaşmaz, Selami

    2015-06-01

    The microwave-assisted synthesis and characterization of novel non-peripherally eugenol substituted metallophthalocyanines (M: Co(II), Ni(II), Cu(II), Zn(II)) have been reported for the first time in this study. All the new compounds were characterized by a combination of FT-IR, 1H NMR, 13C NMR, and UV/vis spectroscopy techniques. The crystal structure of compound (1) was also determined by the single crystal diffraction technique. Newly synthesized eugenol substituted phthalocyanines have more redshift Q bands (about 17-18 nm) than previously reported eugenol substituted phthalocyanines. Zinc(II)phthalocyanine (1d) has an extra absorption band at 746 nm that calling "X band" at UV/vis spectrum.

  3. Synthesis, spectroscopic characterization, molecular modeling and antimicrobial activities of Mn(II), Co(II), Ni(II), Cu(II) complexes containing the tetradentate aza Schiff base ligand

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Ruchi

    2013-02-01

    Mn(II), Co(II), Ni(II), and Cu(II) complexes with a tetradentate macrocyclic ligand [1.2.5.6tetraoxo-3,4,7,8tetraaza-(1,2,3,4,5,6,7,8)tetrabenzene(L)] were synthesized and characterized by elemental analysis, molar conductance measurements, mass, nmr, i.r., electronic and e.p.r. spectral studies. All the complexes are non electrolytes in nature and may be formulated as [M(L)X2] [where, M = Mn(II), Co(II), Ni(II), Cu(II) and X = Cl-, CH3COO-]. On the basis of i.r., electronic and e.p.r. spectral studies a distorted octahedral geometry has been assigned for all complexes. The antimicrobial activities and LD50 values of the ligand and its complexes, as growth inhibiting agents, have been screened in vitro against two different species of bacteria and plant pathogenic fungi.

  4. Synthesis and X-ray structure analysis of a new binuclear Schiff base Co(II) complex with the ligand N,N'-bis(3-methoxysalicylidene)-1,4-butanediamine

    SciTech Connect

    Nasr-Esfahani, M.

    2009-12-15

    The title binuclear complex, tris[N,N-bis(3-methoxysalicylidene)-1,4-diaminobutane] dicobalt(II), C{sub 60}H{sub 70}Co{sub 2}N{sub 6}O{sub 15}, was prepared by the reaction of the tetradentate Schiff base ligand bis(3-methoxysalicylidene)-1,4-diaminobutane and Co(CH{sub 3}COO){sub 2} . 4H{sub 2}O in a ethanol solution and structurally characterized by single-crystal X-ray diffraction. This complex has a dinuclear structure where two Co(II) ions are bridged by one N{sup 0},N'-bis(3-methoxysalicylidene)-1,4-diaminobutane. The two Co(II) ions, have two distorted octahedral coordination involving two O and two N atoms.

  5. Antibacterial Co(II) and Ni(II) Complexes of N-(2-Furanylmethylene)-2-Aminothiadiazole and Role of SO42−, NO3−, C2O42− and CH3CO2− anions on Biological Properties

    PubMed Central

    Rauf, Abdul; Supuran, Claudiu T.

    2002-01-01

    Co(II) and Ni(II) complexes with a Schiff base, N-(2-furanylmethylene)-2-aminothiadiazole have been prepared and characterized by their physical, spectral and analytical data. The synthesized Schiff-bases act as tridentate ligands during the complexation reaction with Co(II) and Ni(II. metal ions. They possess the composition [M(L)2]Xn (where M=Co(II) or Ni(II), L=, X=NO3−, SO42−, C2O42− or CH3CO2− and n=1 or 2) and show an octahedral geometry. In order to evaluate the effect of anions upon chelation, the Schiff-base and its complexes have been screened for antibacterial activity against bacterial strains e.g., Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. PMID:18476008

  6. On the Importance of Noncovalent Carbon-Bonding Interactions in the Stabilization of a 1D Co(II) Polymeric Chain as a Precursor of a Novel 2D Coordination Polymer.

    PubMed

    Pal, Pampi; Konar, Saugata; Lama, Prem; Das, Kinsuk; Bauzá, Antonio; Frontera, Antonio; Mukhopadhyay, Subrata

    2016-07-14

    A new cobalt(II) coordination polymer 2 with μ1,5 dicyanamide (dca) and a bidentate ligand 3,5-dimethyl-1-(2'-pyridyl)pyrazole (pypz) is prepared in a stepwise manner using the newly synthesized one-dimensional linear Co(II) coordination polymer 1 as a precursor. The structural and thermal characterizations elucidate that the more stable complex 2 shows a two-dimensional layer structural feature. Here, Co(II) atoms with μ1,5 dicyanamido bridges are linked by the ligand pypz forming a macrocyclic chain that runs along the crystallographic 'c' axis having 'sql' (Shubnikov notation) net topology with a 4-connected uninodal node having point symbol {4(4).6(2)}. The remarkable noncovalent carbon-bonding contacts detected in the X-ray structure of compound 1 are analyzed and characterized by density functional theory calculations and the analysis of electron charge density (atoms in molecules). PMID:27295490

  7. Electronic, epr and magnetic studies of Co(II), Ni(II) and Cu(II) complexes with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from pyrole-2-carboxyaldehyde

    NASA Astrophysics Data System (ADS)

    Chandra, Sulekh; Kumar, Anil

    2007-07-01

    Co(II), Ni(II) and Cu(II) complexes are synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from pyrole-2-carboxyaldehyde. These complexes are characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies .The molar conductance measurements of the complexes in DMSO correspond to non-electrolytic nature except Co(L 1) 2(NO 3) 2 and Ni(L 1) 2(NO 3) 2 complexes which are 1:2 electrolytes. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry may be assigned for Co(II) and Ni(II) complexes except Co(L 1) 2(NO 3) 2 and Ni(L 1) 2(NO 3) 2 which are of tetrahedral geometry. A tetragonal geometry may be suggested for Cu(II) complexes.

  8. On the Importance of Noncovalent Carbon-Bonding Interactions in the Stabilization of a 1D Co(II) Polymeric Chain as a Precursor of a Novel 2D Coordination Polymer.

    PubMed

    Pal, Pampi; Konar, Saugata; Lama, Prem; Das, Kinsuk; Bauzá, Antonio; Frontera, Antonio; Mukhopadhyay, Subrata

    2016-07-14

    A new cobalt(II) coordination polymer 2 with μ1,5 dicyanamide (dca) and a bidentate ligand 3,5-dimethyl-1-(2'-pyridyl)pyrazole (pypz) is prepared in a stepwise manner using the newly synthesized one-dimensional linear Co(II) coordination polymer 1 as a precursor. The structural and thermal characterizations elucidate that the more stable complex 2 shows a two-dimensional layer structural feature. Here, Co(II) atoms with μ1,5 dicyanamido bridges are linked by the ligand pypz forming a macrocyclic chain that runs along the crystallographic 'c' axis having 'sql' (Shubnikov notation) net topology with a 4-connected uninodal node having point symbol {4(4).6(2)}. The remarkable noncovalent carbon-bonding contacts detected in the X-ray structure of compound 1 are analyzed and characterized by density functional theory calculations and the analysis of electron charge density (atoms in molecules).

  9. Low-Temperature Chemical Vapor Deposition of Silicon Dioxide Using Tetra-isocyanate-silane ( Si(NCO)4)

    NASA Astrophysics Data System (ADS)

    Taniguchi, Hitoshi; Sugiura, Osamu

    1994-10-01

    Deposition characteristics and step coverage of low-temperaturechemical vapor deposition silicon dioxide (CVD SiO2) using tetra-isocyanate-silane ( Si(NCO)4; TICS) and H2Ohave been investigated for application to interlayerdielectric films for advanced VLSI.The deposition rate was 13 nm/min at 100°C.The rate rapidly decreased with the increasing deposition temperature.It was determined by partial pressure rather than by flow rate of material gases.The step coverage showed a conformal profile.

  10. Tetra methyl substituted Cu(II) phthalocyanine as alternative hole transporting material for organometal halide perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Sfyri, Georgia; Kumar, Challuri Vijay; Wang, Yu-Long; Xu, Zong-Xiang; Krontiras, C. A.; Lianos, Panagiotis

    2016-01-01

    Copper phthalocyanine is a promising hole transporting material, which can be employed with solid state perovskite solar cells. Tetra methyl substituted copper phthalocyanine was presently studied as a hole transporting material and demonstrated improved performance with respect to unsubstituted copper phthalocyanine. This material shows a strong absorption in the Visible and Near IR part of the electromagnetic spectrum contributing to the absorption of photons. Its LUMO and HOMO level are favourably positioned for injecting electrons and scavenging holes. Methyl substitution facilitates closer molecular packing leading to a stronger extinction coefficient, stronger π-π interaction and higher charge carrier mobility.

  11. Fabricating photoswitches and field-effect transistors from self-assembled tetra(2-isopropyl-5-methyphenoxy) copper phthalocyanines nanowires.

    PubMed

    Cheng, Chuanwei; Gao, Junshan; Xu, Guoyue; Zhang, Haiqian; Li, Yingying; Luo, Yan

    2009-05-01

    Tetra(2-isopropyl-5-methyphenoxy) copper phthalocyanine (CuPc) nanowires synthesized by a facile, low temperature self-assembled route, were incorporated into nano-devices: photoswitch and organic field-effect transistor. The devices were capable of switching on/off reversibly and fast by turning the 808 nm infrared light on/off. And the carrier mobility micro of CuPc nanowires incorporated in the devices was -0.02 cm2/V x s. The prelimenary results in this study show the potential application of metal phthalocyanine nanowires in low-cost fabrication of nano photo-electric devices.

  12. n-Propyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyran­oside

    PubMed Central

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

    2013-01-01

    The title compound [systematic name: (2R,3R,4S,5R,6R)-2-(acet­oxy­meth­yl)-6-propoxytetra­hydro-2H-pyran-3,4,5-triyl triacetate], C17H26O10, 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 inter­actions such as hydrogen bonds. PMID:23424448

  13. 2-Oxo-4-phenyl-1,2,5,6-tetra-hydro-benzo[h]quinoline-3-carbonitrile.

    PubMed

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

    2011-09-01

    In the mol-ecule of the title compound, C(20)H(14)N(2)O, the tetra-hydro-benzo[h]quinoline fused-ring system is buckled owing to the ethyl-ene -CH(2)CH(2)- fragment, the benzene ring and the pyridine ring being twisted by 19.7 (1)°. The 4-substituted aromatic ring is bent away from the pyridine ring by 62.9 (1)° in order to avoid crowding the cyanide substituent. In the crystal, two mol-ecules are linked by a pair of N-H⋯O hydrogen bonds to form a centrosymmetric dimer. PMID:22065624

  14. Crystal structure of azido-(η(5)-cyclo-penta-dien-yl)bis-(tri-phenyl-phosphane-κP)ruthenium(II) di-chloro-methane hemisolvate.

    PubMed

    Hernández-Calva, Adriana; Meléndez-Balbuena, Lidia; Arroyo, Maribel; Ramírez-Monroy, Armando

    2014-10-01

    The title solvated complex, [Ru(η(5)-C5H5)(N3){P(C6H5)3}2]·0.5CH2Cl2, displays a typical piano-stool geometry about the Ru(II) atom. The bond lengths and angles of the cyclo-penta-dienyl and phosphane ligands are very similar to that of the unsolvated complex [Taqui Khan et al. (1994 ▶). Acta Cryst. C50, 502-504]. The azide anion displays similar N-N distances of 1.173 (3) and 1.156 (3) Å and has an N-N-Ru angle of 119.20 (15)°, indicating a greater contribution of the canonical form Ru-N=N((+))=N((-)) for the bonding situation. An intra-molecular C-H⋯N hydrogen-bonding inter-action between one ortho H atom of a phosphane ligand and the N atom coordinating to the metal is observed. A similar inter-molecular inter-action is observed between a meta H atom of a phosphane ligand and the terminal azide N atom of a neighbouring complex. Finally, two C-H⋯N inter-actions exists between the H atoms of the di-chloro-methane solvent mol-ecule and the terminal N atom of two azide anions. The solvent mol-ecule is located about a twofold rotation axis and shows disorder of the Cl atoms with an occupancy ratio of 0.62 (3):0.38 (3). PMID:25484673

  15. Crystal structure of calpain-3 penta-EF-hand (PEF) domain - a homodimerized PEF family member with calcium bound at the fifth EF-hand

    SciTech Connect

    Partha, Sarathy K.; Ravulapalli, Ravikiran; Allingham, John S.; Campbell, Robert L.; Davies, Peter L.

    2014-08-21

    Calpains are Ca2+dependent intracellular cysteine proteases that cleave a wide range of protein substrates to help implement Ca2+ signaling in the cell. The major isoforms of this enzyme family, calpain-1 and calpain-2, are heterodimers of a large and a small subunit, with the main dimer interface being formed through their C-terminal penta-EF hand (PEF) domains. Calpain-3, or p94, is a skeletal muscle-specific isoform that is genetically linked to limb-girdle muscular dystrophy. Biophysical and modeling studies with the PEF domain of calpain-3 support the suggestion that full-length calpain-3 exists as a homodimer. Here, we report the crystallization of calpain-3's PEF domain and its crystal structure in the presence of Ca2+, which provides evidence for the homodimer architecture of calpain-3 and supports the molecular model that places a protease core at either end of the elongated dimer. Unlike other calpain PEF domain structures, the calpain-3 PEF domain contains a Ca2+ bound at the EF5-hand used for homodimer association. Three of the four Ca2+-binding EF-hands of the PEF domains are concentrated near the protease core, and have the potential to radically change the local charge within the dimer during Ca2+ signaling. Examination of the homodimer interface shows that there would be steric clashes if the calpain-3 large subunit were to try to pair with a calpain small subunit.

  16. The hydrolyzable gallotannin, penta-O-galloyl-β-D-glucopyranoside, inhibits the formation of advanced glycation endproducts by protecting protein structure.

    PubMed

    Ma, Hang; Liu, Weixi; Frost, Leslie; Wang, Ling; Kong, Liwen; Dain, Joel A; Seeram, Navindra P

    2015-05-01

    Glycation is a spontaneous process initiated by a condensation reaction between reducing sugars and proteins that leads to the formation of advanced glycation endproducts (AGEs). The in vivo accumulation of AGEs is associated with several chronic human diseases and, thus, the search for AGE inhibitors is of great research interest. Hydrolyzable tannins (gallotannins and ellagitannins) are bioactive plant polyphenols which show promise as natural inhibitors of glycation and AGE formation. Notably, the gallotannin, 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), is a key intermediate involved in the biosynthesis of hydrolyzable tannins in plants. Herein, we investigated the effects of PGG on the individual stages of protein glycation and on protein structure (using bovine serum albumin; BSA). MALDI-TOF data demonstrated that PGG inhibited early glycation by 75% while the synthetic AGE inhibitor, aminoguanidine (AG), was not active (both at 50 μM). In addition, PGG reduced the formation of middle and late stage AGEs by 90.1 and 60.5%, respectively, which was superior to the positive control, AG. While glycation induced conformational changes in BSA from α-helix to β-sheets (from circular dichroism and congo red binding studies), PGG (at 50 μM) reduced this transition by 50%. Moreover, BSA treated with PGG was more stable in its structure and retained its biophysical properties (based on zeta potential and electrophoretic mobility measurements). The interaction between PGG and BSA was further supported by molecular docking studies. Overall, the current study adds to the growing body of data supporting the anti-AGE effects of hydrolyzable tannins, a ubiquitous class of bioactive plant polyphenols.

  17. The hydrolyzable gallotannin, penta-O-galloyl-β-D-glucopyranoside, inhibits the formation of advanced glycation endproducts by protecting protein structure.

    PubMed

    Ma, Hang; Liu, Weixi; Frost, Leslie; Wang, Ling; Kong, Liwen; Dain, Joel A; Seeram, Navindra P

    2015-05-01

    Glycation is a spontaneous process initiated by a condensation reaction between reducing sugars and proteins that leads to the formation of advanced glycation endproducts (AGEs). The in vivo accumulation of AGEs is associated with several chronic human diseases and, thus, the search for AGE inhibitors is of great research interest. Hydrolyzable tannins (gallotannins and ellagitannins) are bioactive plant polyphenols which show promise as natural inhibitors of glycation and AGE formation. Notably, the gallotannin, 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), is a key intermediate involved in the biosynthesis of hydrolyzable tannins in plants. Herein, we investigated the effects of PGG on the individual stages of protein glycation and on protein structure (using bovine serum albumin; BSA). MALDI-TOF data demonstrated that PGG inhibited early glycation by 75% while the synthetic AGE inhibitor, aminoguanidine (AG), was not active (both at 50 μM). In addition, PGG reduced the formation of middle and late stage AGEs by 90.1 and 60.5%, respectively, which was superior to the positive control, AG. While glycation induced conformational changes in BSA from α-helix to β-sheets (from circular dichroism and congo red binding studies), PGG (at 50 μM) reduced this transition by 50%. Moreover, BSA treated with PGG was more stable in its structure and retained its biophysical properties (based on zeta potential and electrophoretic mobility measurements). The interaction between PGG and BSA was further supported by molecular docking studies. Overall, the current study adds to the growing body of data supporting the anti-AGE effects of hydrolyzable tannins, a ubiquitous class of bioactive plant polyphenols. PMID:25789915

  18. Penta-O-galloyl-β-D-glucose ameliorates inflammation by inhibiting MyD88/NF-κB and MyD88/MAPK signalling pathways

    PubMed Central

    Jang, Se-Eun; Hyam, Supriya R; Jeong, Jin-Ju; Han, Myung Joo; Kim, Dong-Hyun

    2013-01-01

    Background and Purpose The gallnut of Rhus chinensis MILL and its main constituent penta-O-galloyl-β-D-glucose (PGG) inhibited NF-κB activation in LPS-stimulated peritoneal and colonic macrophages. Here we have investigated PGG mechanisms underlying anti-inflammatory effects of PGG in vitro and in vivo. Experimental Approach Male C57BL/6 mice (18–22 g, 6 weeks old) were used to prepare peritoneal and colonic macrophages and for the induction of colitis by intrarectal administration of 2,3,4-trinitrobenzene sulphonic acid (TNBS). A range of inflammatory markers and transcription factors were evaluated by elisa, immunoblotting, flow cytometry and confocal microscopy. Key Results Expression of Toll-like receptor (TLR)-4 or Lipopolysaccharide (LPS) binding to TLR-4 in LPS-stimulated peritoneal macrophages was not affected by PGG. However PGG inhibited binding of an anti-MyD88 antibody to peritoneal macrophages, but did not reduce binding of anti–IL-1 receptor-associated kinase (IRAK1) and IRAK4 antibodies to the macrophages with or without transfection with MyD88 siRNA. PGG potently reduced the activation of IRAK1, NF-κB, and MAPKs in LPS- or pepetidoglycan-stimulated peritoneal and colonic macrophages. PGG suppressed IL-1β, TNF-α and IL-6 in LPS-stimulated peritoneal macrophages, while increasing expression of the anti-inflammatorycytokine IL-10. Oral administration of PGG inhibited colon shortening and myeloperoxidase activity in mice with TNBS-induced colitis, along with reducing NF-κB activation and IL-1β, TNF-α, and IL-6 levels, whereas it increased IL-10. Conclusions and Implications PGG reduced activation of NF-κB and MAPK signalling pathways by directly interacting with the MyD88 adaptor protein. PGG may ameliorate inflammatory diseases such as colitis. PMID:23941302

  19. Opposing Effects of Cucurbit[7]uril and 1,2,3,4,6-Penta-O-galloyl-β-d-glucopyranose on Amyloid β25-35 Assembly.

    PubMed

    de Almeida, Natália E C; Do, Thanh D; Tro, Michael; LaPointe, Nichole E; Feinstein, Stuart C; Shea, Joan-Emma; Bowers, Michael T

    2016-02-17

    Alzheimer's disease (AD) is a neurodegenerative disease characterized by extracellular deposits of amyloid β protein (Aβ) in the brain. The conversion of soluble monomers to amyloid Aβ fibrils is a complicated process and involves several transient oligomeric species, which are widely believed to be highly toxic and play a crucial role in the etiology of AD. The development of inhibitors to prevent formation of small and midsized oligomers is a promising strategy for AD treatment. In this work, we employ ion mobility spectrometry (IMS), transmission electron microscopy (TEM), and molecular dynamics (MD) simulations to elucidate the structural modulation promoted by two potential inhibitors of Aβ oligomerization, cucurbit[7]uril (CB[7]) and 1,2,3,4,6-penta-O-galloyl-β-d-glucopyranose (PGG), on early oligomer and fibril formation of the Aβ25-35 fragment. One and two CB[7] molecules bind to Aβ25-35 monomers and dimers, respectively, and suppress aggregation by remodeling early oligomer structures and inhibiting the formation of higher-order oligomers. On the other hand, nonselective binding was observed between PGG and Aβ25-35. The interactions between PGG and Aβ25-35, surprisingly, enhanced the formation of Aβ aggregates by promoting extended Aβ25-35 conformations in both homo- and hetero-oligomers. When both ligands were present, the inhibitory effect of CB[7] overrode the stimulatory effect of PGG on Aβ25-35 aggregation, suppressing the formation of large amyloid oligomers and eliminating the structural conversion from isotropic to β-rich topologies induced by PGG. Our results provide mechanistic insights into CB[7] and PGG action on Aβ oligomerization. They also demonstrate the power of the IMS technique to investigate mechanisms of multiple small-molecule agents on the amyloid formation process. PMID:26629788

  20. Analgesic effects of 1,2,3,4,6-penta-O-galloyl-β-D-glucose in an animal model of lipopolysaccharide-induced pain.

    PubMed

    Chun, Kun; Kim, Si-Oh; Lee, Sang-Han

    2016-10-01

    We examined the analgesic effects of 1,2,3, 4,6-penta-O-galloyl-β-D-glucose (β-PGG), a prototypical gallotannin, in an animal model of lipopolysaccharide (LPS)‑induced pain. To evaluate the analgesic activity of β-PGG, we assessed the potential of β-PGG to inhibit the generation of nitric oxide (NO) in LPS-stressed RAW 264.7 cells, and found that β-PGG inhibits NO generation in a dose-dependent manner. Furthermore, the effects of β-PGG on the voluntary movements of LPS-exposed animals were evaluated. The results showed that the voluntary movements of animals were markedly recovered after β-PGG treatment. The mRNA expression of interleukin (IL)-1β (1.33±0.38-fold) and IL-6 (0.64±0.40-fold) in the brain tissue of β-PGG-treated animals markedly decreased compared with that observed in the control groups (3.86±0.91 and 2.45±1.12-fold, respectively) and in the other LPS-administered groups. The results showed that β-PGG has potential to alleviate pain, not only by decreasing cellular NO generation in RAW 264.7 cells but also by the recovery of voluntary movement lost owing to inflammatory pain. This suggests that β-PGG is comparable to ibuprofen, which was used as a positive control in this study. Collectively, these findings suggest that β-PGG is a valuable natural compound which possesses analgesic activity. PMID:27600119

  1. Synthesis, spectral characterization and thermal studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes with 2-amino benzoic acid- and 2-hydroxy benzoic acid thiophen-2-ylmethylene hydrazide

    NASA Astrophysics Data System (ADS)

    Singh, Vinod P.; Singh, Pooja

    2013-03-01

    A series of metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) with 2-amino benzoic acid thiophen-2-ylmethylene hydrazide (Habth) and 2-hydroxy benzoic acid thiophen-2-ylmethylene hydrazide (Hhbth) have been synthesized. The complexes were characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, electronic, IR, NMR, ESR spectra and thermal studies (TGA and DTA). Molecular structure of the Habth ligand was determined by single crystal X-ray diffraction technique. Habth acts as a monobasic bidentate ligand in all its complexes bonding through a deprotonated Csbnd O- and lbond2 Cdbnd Nsbnd groups whereas, Hhbth acts as a monobasic bidentate in its Co(II) and Ni(II) complexes, bonding through a deprotonated Csbnd O- and lbond2 Cdbnd Nsbnd groups and as monobasic tridentate in Cu(II) and Zn(II) complexes bonding through lbond2 Cdbnd O, lbond2 Cdbnd Nsbnd and deprotonated (Csbnd O)- groups with the metal ion. Electronic spectra suggest a square planar geometry for Co(II), Ni(II) and Cu(II) complexes of Habth and Co(II) and Ni(II) complexes of Hhbth. However, the Cu(II) and Zn(II) complexes of Hhbth have octahedral geometry. The ESR spectra of Cu(II) complex of Hhbth in the solid state and in DMSO frozen solution show axial signals and suggest the presence of unpaired electron in d orbital of Cu(II). The Cu(II) complex of Habth in solid state shows isotropic signal, whereas, axial signal in DMSO frozen solution in the range of tetragonally distorted octahedral geometry due to interactions of DMSO molecules at axial positions. Thermal studies of some of the metal complexes show a multi-step decomposition pattern of bonded ligands in the complex.

  2. Synthesis, characterization and in vitro antimicrobial studies of Co(II), Ni(II) and Cu(II) complexes derived from macrocyclic compartmental ligand.

    PubMed

    El-Gammal, O A; Bekheit, M M; El-Brashy, S A

    2015-02-25

    New Co(II), Ni(II) and Cu(II) complexes derived from tetradentate macrocyclic nitrogen ligand, (1E,4E,8E,12E)-5,8,13,16-tetramethyl-1,4,9,12-tetrazacyclohexadeca-4,8,12,16-tetraene (EDHDH) have been synthesized. The complexes have been characterized by elemental analysis, spectral (IR, UV-Vis, (1)H NMR and ESR (for Cu(II) complex)) mass, and magnetic as well as thermal analysis measurements. The complexes afforded the formulae: [Cu(EDHDH)Cl2]·2EtOH and [M(EDHDH)X2]·nH2O where M=Co(II) and Ni(II), X=Cl(-) or OH(-), n=1,0, respectively. The data revealed an octahedral arrangement with N4 tetradentate donor sites in addition to two Cl atoms occupying the other two sites. ESR spectrum of Cu(2+) complex confirmed the suggested geometry with values of a α(2)and β(2) indicating that the in-plane σ-bonding and in-plane π-bonding are appreciably covalent, and are consistent with very strong σ-in-plane bonding in the complexes. The molecular modeling is drawn and showed the bond length, bond angle, chemical reactivity, energy components (kcal/mol) and binding energy (kcal/mol) for all the title compounds using DFT method. Also, the thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. Moreover, the in vitro antibacterial studies of all compounds screened against pathogenic bacteria (two Gram +ve and two Gram -ve) to assess their inhibiting potential. The assay indicated that the inhibition potential is metal ion dependent. The ligand, EDHDH, Co(II) and Cu(II) complexes exhibited a remarkable antibacterial activity against Streptococcus Pyogenes as Gram +ve and Proteus vulgaris as Gram -ve bacterial strains. On the other hand, Ni(II) complex revealed a moderate antibacterial activity against both Gram +ve organisms and no activity against Gram -ve bacterial strain.

  3. Synthesis, characterization and in vitro antimicrobial studies of Co(II), Ni(II) and Cu(II) complexes derived from macrocyclic compartmental ligand.

    PubMed

    El-Gammal, O A; Bekheit, M M; El-Brashy, S A

    2015-02-25

    New Co(II), Ni(II) and Cu(II) complexes derived from tetradentate macrocyclic nitrogen ligand, (1E,4E,8E,12E)-5,8,13,16-tetramethyl-1,4,9,12-tetrazacyclohexadeca-4,8,12,16-tetraene (EDHDH) have been synthesized. The complexes have been characterized by elemental analysis, spectral (IR, UV-Vis, (1)H NMR and ESR (for Cu(II) complex)) mass, and magnetic as well as thermal analysis measurements. The complexes afforded the formulae: [Cu(EDHDH)Cl2]·2EtOH and [M(EDHDH)X2]·nH2O where M=Co(II) and Ni(II), X=Cl(-) or OH(-), n=1,0, respectively. The data revealed an octahedral arrangement with N4 tetradentate donor sites in addition to two Cl atoms occupying the other two sites. ESR spectrum of Cu(2+) complex confirmed the suggested geometry with values of a α(2)and β(2) indicating that the in-plane σ-bonding and in-plane π-bonding are appreciably covalent, and are consistent with very strong σ-in-plane bonding in the complexes. The molecular modeling is drawn and showed the bond length, bond angle, chemical reactivity, energy components (kcal/mol) and binding energy (kcal/mol) for all the title compounds using DFT method. Also, the thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. Moreover, the in vitro antibacterial studies of all compounds screened against pathogenic bacteria (two Gram +ve and two Gram -ve) to assess their inhibiting potential. The assay indicated that the inhibition potential is metal ion dependent. The ligand, EDHDH, Co(II) and Cu(II) complexes exhibited a remarkable antibacterial activity against Streptococcus Pyogenes as Gram +ve and Proteus vulgaris as Gram -ve bacterial strains. On the other hand, Ni(II) complex revealed a moderate antibacterial activity against both Gram +ve organisms and no activity against Gram -ve bacterial strain. PMID:25218230

  4. Spectroscopic, magnetic and thermal studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes of 3-acetylcoumarin-isonicotinoylhydrazone and their antimicrobial and anti-tubercular activity evaluation

    NASA Astrophysics Data System (ADS)

    Hunoor, Rekha S.; Patil, Basavaraj R.; Badiger, Dayananda S.; Vadavi, Ramesh S.; Gudasi, Kalagouda B.; Chandrashekhar, V. M.; Muchchandi, I. S.

    2010-11-01

    Co(II), Ni(II), Cu(II) and Zn(II) complexes with a new heterocyclic Schiff base derived by the condensation of isonicotinoylhydrazide and 3-acetylcoumarin have been synthesized. 1H, 13C and 2D HETCOR NMR analyses confirm the formation of title compound and existence of the same in two isomeric forms. The metal complexes were characterized on the basis of various spectroscopic techniques like electronic, EPR, IR, 1H and 13C NMR studies, elemental analysis, magnetic properties and thermogravimetric analysis, and also by the aid of molar conductivity measurements. It is found that the Schiff base behaves as a monobasic tridentate ligand coordinating in the imidol form with 1:1 metal to ligand stoichiometry. Trigonal bipyramidal geometry has been assigned for Ni(II) and Cu(II) complexes, while tetrahedral for Co(II) and Zn(II) complexes. The compounds were subjected to antimicrobial and anti-tubercular activity screening using serial broth dilution method and Minimum Inhibitory Concentration (MIC) is determined. Zn(II) complex has shown significant antifungal activity with an MIC of 6.25 μg/mL while Cu(II) complex is noticeable for antibacterial activity at the same concentration. Anti-TB activity of the ligand has enhanced on complexation with Co(II) and Ni(II) ions.

  5. Theoretical and experimental studies on three new coordination complexes of Co(II), Ni(II), and Cu(II) with 2,4-dichloro-6-{(E)-[(5-chloro-2 sulfanylphenyl)imino]methyl}phenol Schiff base ligand.

    PubMed

    Kusmariya, Brajendra S; Mishra, A P

    2015-11-01

    Three mononuclear coordination complexes of Co(II), Ni(II), and Cu(II) have been synthesized from 2,4-dichloro-6-{(E)-[(5-chloro-2-sulfanylphenyl)imino]methyl}phenol ligand (H 2 L) obtained by simple condensation reaction of 3,5-dichloro-2-hydroxybenzaldehyde and 2-amino-4-chlorobenzenethiol and characterized by elemental analysis, spectral (FT-IR, electronic, and (1)H-NMR), molar conductance, thermal, SEM, PXRD, and fluorescence studies. The PXRD analysis and SEM-EDX micrographs show the crystalline nature of complexes. The domain size and the lattice strain of synthesized compounds have been determined according to Williamson-Hall plot. TG of the synthesized complexes illustrates the general decomposition pattern of the complexes. The ligand exhibits an interesting fluorescence property which is suppressed after complex formation. The Co(II) complex adopted a distorted octahedral configuration while Ni(II) and Cu(II) complexes showed square planar geometry around metal center. The geometry optimization, HOMO-LUMO, molecular electrostatic potential map (MEP), and spin density of synthesized compounds have been performed by density functional theory (DFT) method using B3LYP/6-31G and B3LYP/LANL2DZ as basis set. Graphical abstract Three new coordination complexes of Co(II), Ni(II) and Cu(II) with 2,4-dichloro-6-{(E)-[(5-chloro-2 sulfanylphenyl)imino]methyl}phenol Schiff base ligand. PMID:26438445

  6. Determination of Pb(II), Zn(II), Cd(II), and Co(II) ions by flame atomic absorption spectrometry in food and water samples after preconcentration by coprecipitation with Mo(VI)-diethyldithiocarbamate.

    PubMed

    Tufekci, Mehmet; Bulut, Volkan Numan; Elvan, Hamide; Ozdes, Duygu; Soylak, Mustafa; Duran, Celal

    2013-02-01

    A new, simple, and rapid separation and preconcentration procedure, for determination of Pb(II), Cd(II), Zn(II), and Co(II) ions in environmental real samples, has been developed. The method is based on the combination of coprecipitation of analyte ions by the aid of the Mo(VI)-diethyldithiocarbamate-(Mo(VI)-DDTC) precipitate and flame atomic absorption spectrometric determinations. The effects of experimental conditions like pH of the aqueous solution, amounts of DDTC and Mo(VI), standing time, centrifugation rate and time, sample volume, etc. and also the influences of some foreign ions were investigated in detail on the quantitative recoveries of the analyte ions. The preconcentration factors were found to be 150 for Pb(II), Zn(II) and Co(II), and 200 for Cd(II) ions. The detection limits were in the range of 0.1-2.2 μg L(-1) while the relative standard deviations were found to be lower than 5 % for the studied analyte ions. The accuracy of the method was checked by spiked/recovery tests and the analysis of certified reference material (CRM TMDW-500 Drinking Water). The procedure was successfully applied to seawater and stream water as liquid samples and baby food and dried eggplant as solid samples in order to determine the levels of Pb(II), Cd(II), Zn(II), and Co(II) ions. PMID:22527456

  7. Chelating agent free-solid phase extraction (CAF-SPE) of Co(II), Cu(II) and Cd(II) by new nano hybrid material (ZrO2/B2O3).

    PubMed

    Yalçinkaya, Ozcan; Kalfa, Orhan Murat; Türker, Ali Rehber

    2011-11-15

    New nano hybrid material (ZrO(2)/B(2)O(3)) was synthesized and applied as a sorbent for the separation and/or preconcentration of Co(II), Cu(II) and Cd(II) in water and tea leaves prior to their determination by flame atomic absorption spectrometry. Synthesized nano material was characterized by scanning electron microscope, transmission electron microscope and X-ray diffraction. The optimum conditions for the quantitative recovery of the analytes, including pH, eluent type and volume, flow rate of sample solution were examined. The effect of interfering ions was also investigated. Under the optimum conditions, adsorption isotherms and adsorption capacities have been examined. The recoveries of Co(II), Cu(II) and Cd(II) were 96 ± 3%, 95 ± 3%, 98 ± 4% at 95% confidence level, respectively. The analytical detection limits for Co(II), Cu(II), and Cd(II) were 3.8, 3.3, and 3.1 μg L(-1), respectively. The reusability and adsorption capacities (32.2 mg g(-1) for Co, 46.5 mg g(-1) for Cu and 109.9 mg g(-1) for Cd) of the sorbent were found as satisfactory. The accuracy of the method was confirmed by analyzing certified reference material (GBW-07605 Tea leaves) and spiked real samples. The method was applied for the determination of analytes in tap water and tea leaves.

  8. (2,3,5,6-Tetra­fluoro­phenolato)[5,10,15,20-tetra­kis­(4-meth­oxy­phen­yl)porphyrinato]iron(III) cyclo­hexane monosolvate

    PubMed Central

    Xu, Nan; Powell, Douglas R.; Richter-Addo, George B.

    2013-01-01

    The title compound, [Fe(C6HF4O)(C48H36N4O4)]·C6H12, represents a five-coordinate iron(III) porphyrin complex in a square-pyramidal geometry with a tetra­fluoro­phenolate anion as the axial ligand. The FeIII atom is displaced by 0.364 (2) Å from the 24-atom mean plane of the porphyrinate ring towards the tetra­fluoro phenolate anion. The average Fe—N distance is 2.053 (2) Å and the Fe—O distance is 1.883 (2) Å. A porphyrin aryl H atom points in the general direction of the phenoxide ring. The mean plane separation between the 24-atom porphyrin planes of two adjacent porphyrin rings is ∼3.7 Å, and the lateral shift is ∼3.5 Å resu, ting in an Fe⋯Fe separation of 5.6167 (14) Å. PMID:24098166

  9. Delivery of Methylene Blue and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate from cross-linked poly(vinyl alcohol) hydrogels: a potential means of photodynamic therapy of infected wounds.

    PubMed

    Donnelly, Ryan F; Cassidy, Corona M; Loughlin, Ryan G; Brown, Anthony; Tunney, Michael M; Jenkins, Mark G; McCarron, Paul A

    2009-09-01

    Poly(vinyl alcohol)-borate complexes were evaluated as a potentially novel drug delivery platform suitable for in vivo use in photodynamic antimicrobial chemotherapy (PACT) of wound infections. An optimised formulation (8.0%w/w PVA, 2.0%w/w borax) was loaded with 1.0 mg ml(-1) of the photosensitisers Methylene Blue (MB) and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP). Both drugs were released to yield receiver compartment concentrations (>5.0 microg ml(-1)) found to be phototoxic to both planktonic and biofilm-grown methicillin-resistant Staphylococcus aureus (MRSA), a common cause of wound infections in hospitals. Newborn calf serum, used to simulate the conditions prevalent in an exuding wound, did not adversely affect the properties of the hydrogels and had no significant effect on the rate of TMP-mediated photodynamic kill of MRSA, despite appreciably reducing the fluence rate of incident light. However, MB-mediated photodynamic kill of MRSA was significantly reduced in the presence of calf serum and when the clinical isolate was grown in a biofilm. Results support the contention that delivery of MB or TMP using gel-type vehicles as part of PACT could make a contribution to the photodynamic eradication of MRSA from infected wounds.

  10. Di-μ-hydroxido-bis­[hemiaqua­(N,N,N′,N′-tetra­methyl­ethane-1,2-diamine)­copper(II)] bis­(tetra­fluoridoborate)

    PubMed Central

    Haníková, Jaroslava; Kuchár, Juraj; Trávníček, Zdeněk; Černák, Juraj

    2012-01-01

    The title compound, [Cu2(OH)2(C6H16N2)2(H2O)](BF4)2, consists of dinuclear centrosymmetric [Cu2(OH)2(tmen)2(H2O)]2+ complex cations (tmen = N,N,N′,N′-tetra­methyl­ethane-1,2-diamine) and tetra­fluoridoborate anions. In the cation, the CuII atom shows a slightly distorted square-pyramidal coordination geometry provided by a pair of μ-OH− anions and by the N atoms of a chelate tmen ligand in the basal plane. The apical position is statistically occupied by the O atom of a half-occupancy water mol­ecule. The F atoms of the anion are disordered over three sets of sites with occupancies of 0.598 (9):0.269 (6):0.134 (8). The crystal packing is governed by ionic forces as well as by O—H⋯F hydrogen bonds. PMID:22719335

  11. catena-Poly[[[tetra-aqua-cobalt(II)]-μ-4,4'-bipyridine-κN:N'] 2-[4-(2-carboxyl-ato-eth-yl)phen-oxy]acetate].

    PubMed

    Wang, Xi-Fang; Liu, Chong-Bo; Huang, De-He; Xiong, Zhi-Qiang

    2009-06-13

    In the title complex, {[Co(C(10)H(8)N(2))(H(2)O)(4)](C(11)H(10)O(5))}(n), the unique Co(II) ion lies on an inversion center and is coordinated by two N atoms from two 4,4'-bipyridine ligands and four O atoms from four water mol-ecules in a slightly distorted octa-hedral coordination geometry. The 4,4'-bipyridine ligands bridge Co(II) ions into a one-dimensional chain structure. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link cations and anions into a three-dimensional network. The dianions are completely disordered about an inversion center.

  12. Ethyl 1-benzoyl-4-hy­droxy-2,6-diphenyl-1,2,5,6-tetra­hydro­pyridine-3-carboxyl­ate

    PubMed Central

    Aridoss, G.; Sundaramoorthy, S.; Velmurugan, D.; Jeong, Y. T.

    2011-01-01

    In the title compound, C27H25NO4, the tetra­hydro­pyridine ring adopts a half-chair conformation. The three phenyl rings form dihedral angles of 66.33 (7), 87.36 (8) and 36.90 (7)° with the least-squares plane through the tetra­hydro­pyridine ring. The mol­ecular conformation is stabilized by an intra­molecular O—H⋯O hydrogen bond, generating an S(6) motif. PMID:21522308

  13. Hydrogen Permeability of a Polymer Based Composite Tank Material Under Tetra-Axial Strain

    NASA Technical Reports Server (NTRS)

    Stokes, Eric H.

    2003-01-01

    of the microcracks in the material. This paper documents the results of hydrogen permeability testing on a Bismaleimide (BMI) based graphite fiber composite material under a variety of tetra-axial strain states.

  14. Denaturation of Proteins by SDS and by Tetra-alkylammonium Dodecyl Sulfates

    PubMed Central

    Lee, Andrew; Tang, Sindy K. Y.; Mace, Charles R.

    2011-01-01

    This paper describes the use of capillary electrophoresis (CE) to examine the influence of different cations (C+; C+ = Na+ and tetra-n-alkylammonium, NR4 +, where R = Me, Et, Pr, Bu) on the rates of denaturation of bovine carbonic anhydrase II (BCA) in the presence of the anionic surfactant dodecylsulfate (DS−). Analysis of the denaturation of BCA in solutions of Na+DS− and NR4 +DS− (in Tris-Gly buffer) indicated that the rates of formation of complexes of denatured BCA with DS− (BCAD-DS−n,sat) are indistinguishable and independent of the cation below the critical micellar concentration (cmc), and independent of the total concentration of DS− above the cmc. At concentrations of C+DS− above the cmc, BCA denatured with rates that depended on the cation; the rates decreased by a factor > 104, in the order Na+ ~ NMe4 + > NEt4 + > NPr4 + > NBu4 + – the same order as the values of cmc (which decrease from 4.0 mM for Na+DS− to 0.9 mM for NBu4 +DS− in Tris-Gly buffer). The relationship between values of cmc and rates of formation of BCAD-DS−n,sat suggested that the kinetics of denaturation of BCA involve the association of this protein with monomeric DS−, rather than with micelles of (C+DS−)n. A less-detailed survey of seven other proteins (α-lactalbumin, β-lactoglobulin A, β-lactoglobulin B, carboxypeptidase B, creatine phosphokinase, myoglobin, and ubiquitin) showed that the difference between Na+DS− and NR4 +DS− observed with BCA was not general. Instead, the influence of NR4 + on the association of DS− with these proteins depended on the protein. The selection of cation contributed to the properties (including composition, electrophoretic mobility, and partitioning behavior in aqueous two-phase systems) of aggregates of denatured protein and DS−. These results suggest that variation in the behavior of NR4 +DS− with changes in R may be exploited in methods for analyzing and separating mixtures of proteins. PMID:21834533

  15. Methyl tetra-O-acetyl-α-D-glucopyranuronate: crystal structure and influence on the crystallisation of the β anomer.

    PubMed

    Hayes, John A; Eccles, Kevin S; Lawrence, Simon E; Moynihan, Humphrey A

    2016-04-29

    Methyl tetra-O-acetyl-β-D-glucopyranuronate (1) and methyl tetra-O-acetyl-α-D-glucopyranuronate (3) were isolated as crystalline solids and their crystal structures were obtained. That of the β anomer (1) was the same as that reported by Root et al., while anomer (3) was found to crystallise in the orthorhombic space group P212121 with two independent molecules in the asymmetric unit. No other crystal forms were found for either compound upon recrystallisation from a range of solvents. The α anomer (3) was found to be an impurity in initially precipitated batches of β-anomer (1) in quantities <3%; however, it was possible to remove the α impurity either by recrystallisation or by efficient washing, i.e. the α anomer is not incorporated inside the β anomer crystals. The β anomer (1) was found to grow as prisms or needles elongated in the a crystallographic direction in the absence of the α impurity, while the presence of the α anomer (3) enhanced this elongation. PMID:27031190

  16. Integration and optimization of the DUV ALTA pattern generation system using a CAR process with the Tetra photomask etch system

    NASA Astrophysics Data System (ADS)

    Buxbaum, Alex H.; Fuller, Scott E.; Montgomery, Warren; Ungureit, Michael E.

    2003-12-01

    Etec Systems, the Mask Business Group of Applied Materials, is in a unique position within the mask making industry - Etec has the opportunity to integrate individual parts of the overall mask manufacturing process to provide a more complete solution. Here we present the integration of the DUV ALTA laser pattern generator and the TetraTM photomask etch system with advanced CAR resist processes. Dry etch process effects of flow, overetch, and oxygen content (in a Cl2/O2/He plasma) are discussed for the baseline POR resist in terms of etch rate, selectivity, etch bias, CD uniformity and micro-loading; the optimized etch process space was then implemented for advanced CAR resists. Iso-dense bias, football pattern loading and other pattern transfer results influencing mask manufactureability are also presented. Within the synthesis and optimization of the pattern generation system, process, and dry etch sub 13 nm range process uniformity has been achieved. The integrated ALTA / Tetra / Advanced-CAR solution set is characterized on both Etec test patterns and customer demonstrations.

  17. The effect of GSM and TETRA mobile handset signals on blood pressure, catechol levels and heart rate variability.

    PubMed

    Barker, Anthony T; Jackson, Peter R; Parry, Helen; Coulton, Leslie A; Cook, Greg G; Wood, Steven M

    2007-09-01

    An acute rise in blood pressure has been reported in normal volunteers during exposure to signals from a mobile phone handset. To investigate this finding further we carried out a double blind study in 120 healthy volunteers (43 men, 77 women) in whom we measured mean arterial pressure (MAP) during each of six exposure sessions. At each session subjects were exposed to one of six different radio frequency signals simulating both GSM and TETRA handsets in different transmission modes. Blood catechols before and after exposure, heart rate variability during exposure, and post exposure 24 h ambulatory blood pressure were also studied. Despite having the power to detect changes in MAP of less than 1 mmHg none of our measurements showed any effect which we could attribute to radio frequency exposure. We found a single statistically significant decrease of 0.7 mmHg (95% CI 0.3-1.2 mmHg, P = .04) with exposure to GSM handsets in sham mode. This may be due to a slight increase in operating temperature of the handsets when in this mode. Hence our results have not confirmed the original findings of an acute rise in blood pressure due to exposure to mobile phone handset signals. In light of this negative finding from a large study, coupled with two smaller GSM studies which have also proved negative, we are of the view that further studies of acute changes in blood pressure due to GSM and TETRA handsets are not required. PMID:17486598

  18. The visible light degradation activity and the photocatalytic mechanism of tetra(4-carboxyphenyl) porphyrin sensitized TiO{sub 2}

    SciTech Connect

    Wang, Huigang; Zhou, Dongmei; Wu, Zhangzhu; Wan, Junmin; Zheng, Xuming; Yu, Lihong; Phillips, David Lee

    2014-09-15

    Highlights: • Tetra(4-carboxyphenyl) porphyrin were chemically sensitized on TiO{sub 2}. • S2–S0 fluorescence intensity is enhanced and lifetime prolonged noticeably by TiO{sub 2}. • The TCPP-TiO{sub 2} exhibits better photoactivity under visible light than that of TiO{sub 2}. • The electronic relaxation dynamics is presented, catalytic mechanism is discussed. • Adsorption and photo degradation of MB were systematically investigated. - Abstract: Tetra(4-carboxyphenyl) porphyrin(TCPP) were chemically sensitized on TiO{sub 2} to act as visible light antenna and to modify the photoresponse properties of TiO{sub 2} particles, their properties of photo-generated holes and electrons were studied by transient absorption spectroscopes. The time-correlated single-photon counting (TCSPC) technique revealed that the S2–S0 fluorescence intensity of TCPP is enhanced noticeably by TiO{sub 2}, and the lifetime prolonged. Adsorption and photo degradation of methylene blue (MB) over TCPP-TiO{sub 2} were systematically investigated. Moreover the overall picture of electronic relaxation dynamics for TCPP-TiO{sub 2} is presented, and the detailed short-time dynamics for visible-light induced catalytic mechanism was discussed. The development of the porphyrin-based photocatalyst provides an alternative approach in harnessing solar visible light and show promising prospect for the treatment of dye pollutants from wastewaters in future industrial application.

  19. A study on chemical composition and detection of chemical adulteration in tetra pack milk samples commercially available in Multan.

    PubMed

    Awan, Adeela; Naseer, Misbah; Iqbal, Aasfa; Ali, Muhammad; Iqbal, Rehana; Iqbal, Furhan

    2014-01-01

    The aim of this study was to analyze and compare the chemical composition of 8 tetra pack milk samples, Olpers (S1), Haleeb (S2), Good milk (S3), Everyday (S4), Milk Pack (S5), Dairy Queen (S6), Dairy Umang (S7), Nurpur (S8) available in local markets and to detect the presence of various chemical adulterants in tetra pack milk samples in Southern Punjab (Pakistan). Density, pH, solid not fat, total solids, lactometer reading, specific gravity and fat contents were analyzed to determine the chemical composition of milk samples. Our results revealed that all the studied parameters had statistically non significant differences (P>0.05) except total fat in milk samples which was significantly different (P=0.03) among the 8 studied milk samples. Presence of a number of chemical adulterants, formalin, cane sugar, starch, glucose, ammonium sulphate, salt, pulverized soap, detergents, skim milk powder, benzoic acid, salicylic acid, borax, boric acid and alkalinity were also detected in milk samples following standard procedures. Results indicated that formalin, cane sugar, glucose, alkalinity and benzoic acid were present in all samples while salt test was positive only for Olper milk. All other studied adulterants were not detected in 8 milk samples under study. % fat was the only significantly different feature among the studied milk quality parameters with S8 containing lowest while S5 having the maximum % fat. PMID:24374447

  20. Suppressing of slow magnetic relaxation in tetracoordinate Co(II) field-induced single-molecule magnet in hybrid material with ferromagnetic barium ferrite

    PubMed Central

    Nemec, Ivan; Herchel, Radovan; Trávníček, Zdeněk

    2015-01-01

    The novel field-induced single-molecule magnet based on a tetracoordinate mononuclear heteroleptic Co(II) complex involving two heterocyclic benzimidazole (bzi) and two thiocyanido ligands, [Co(bzi)2(NSC)2], (CoL4), was prepared and thoroughly characterized. The analysis of AC susceptibility data resulted in the spin reversal energy barrier U = 14.7 cm−1, which is in good agreement with theoretical prediction, Utheor. = 20.2 cm−1, based on axial zero-field splitting parameter D = −10.1 cm−1 fitted from DC magnetic data. Furthermore, mutual interactions between CoL4 and ferromagnetic barium ferrite BaFe12O19 (BaFeO) in hybrid materials resulted in suppressing of slow relaxation of magnetization in CoL4 for 1:2, 1:1 and 2:1 mass ratios of CoL4 and BaFeO despite the lack of strong magnetic interactions between two magnetic phases. PMID:26039085

  1. MtDNA COI-COII marker and drone congregation area: an efficient method to establish and monitor honeybee (Apis mellifera L.) conservation centres.

    PubMed

    Bertrand, Bénédicte; Alburaki, Mohamed; Legout, Hélène; Moulin, Sibyle; Mougel, Florence; Garnery, Lionel

    2015-05-01

    Honeybee subspecies have been affected by human activities in Europe over the past few decades. One such example is the importation of nonlocal subspecies of bees which has had an adverse impact on the geographical repartition and subsequently on the genetic diversity of the black honeybee Apis mellifera mellifera. To restore the original diversity of this local honeybee subspecies, different conservation centres were set up in Europe. In this study, we established a black honeybee conservation centre Conservatoire de l'Abeille Noire d'Ile de France (CANIF) in the region of Ile-de-France, France. CANIF's honeybee colonies were intensively studied over a 3-year period. This study included a drone congregation area (DCA) located in the conservation centre. MtDNA COI-COII marker was used to evaluate the genetic diversity of CANIF's honeybee populations and the drones found and collected from the DCA. The same marker (mtDNA) was used to estimate the interactions and the haplotype frequency between CANIF's honeybee populations and 10 surrounding honeybee apiaries located outside of the CANIF. Our results indicate that the colonies of the conservation centre and the drones of the DCA show similar stable profiles compared to the surrounding populations with lower level of introgression. The mtDNA marker used on both DCA and colonies of the conservation centre seems to be an efficient approach to monitor and maintain the genetic diversity of the protected honeybee populations.

  2. Synthesis, DFT Calculation, and Antimicrobial Studies of Novel Zn(II), Co(II), Cu(II), and Mn(II) Heteroleptic Complexes Containing Benzoylacetone and Dithiocarbamate

    PubMed Central

    Ekennia, Anthony C.; Onwudiwe, Damian C.; Olasunkanmi, Lukman O.; Osowole, Aderoju A.; Ebenso, Eno E.

    2015-01-01

    Heteroleptic complexes of zinc(II), copper(II), manganese(II), and cobalt(II) of the types [MLL′(H2O)2]·nH2O and [MLL′]·nH2O have been synthesized using sodium N-methyl-N-phenyldithiocarbamate (L) and benzoylacetone (L′). The metal complexes were characterized by elemental analysis, electrical conductance, magnetic susceptibility, infrared (IR), and UV-visible spectroscopic studies. The electrical conductance measurements revealed the nonelectrolytic nature of the synthesized complexes. The results of the elemental analyses, magnetic susceptibility measurements, and electronic spectra inferred that the Zn(II) complex adopted a four-coordinate geometry while the Co(II), Cu(II), and Mn(II) complexes assumed octahedral geometries. The IR spectra showed that the metal ions coordinated with the ligands via the S- and O-donor atoms. The geometry, electronic, and thermodynamic parameters of the complexes were obtained from density functional theory (DFT) calculations. The spin density distributions, relative strength of H–bonds, and thermodynamic parameters revealed that the order of stability of the metal complexes is Mn < Co < Cu > Zn. The agar diffusion methods were used to study the antimicrobial activity of the complexes against two Gram positive bacteria (S. aureus and S. pneumoniae), one Gram negative bacterium (E. coli), and two fungi organisms (A. niger and A. candida) and the complexes showed a broad spectrum of activities against the microbes. PMID:26681931

  3. Oxygen Activation by Co(II) and a Redox Non-Innocent Ligand: Spectroscopic Characterization of a Radical-Co(II)-Superoxide Complex with Divergent Catalytic Reactivity.

    PubMed

    Corcos, Amanda R; Villanueva, Omar; Walroth, Richard C; Sharma, Savita K; Bacsa, John; Lancaster, Kyle M; MacBeth, Cora E; Berry, John F

    2016-02-17

    Bimetallic (Et4N)2[Co2(L)2], (Et4N)2[1] (where (L)(3-) = (N(o-PhNC(O)(i)Pr)2)(3-)) reacts with 2 equiv of O2 to form the monometallic species (Et4N)[Co(L)O2], (Et4N)[3]. A crystallographically characterized analog (Et4N)2[Co(L)CN], (Et4N)2[2], gives insight into the structure of [3](1-). Magnetic measurements indicate [2](2-) to be an unusual high-spin Co(II)-cyano species (S = 3/2), while IR, EXAFS, and EPR spectroscopies indicate [3](1-) to be an end-on superoxide complex with an S = 1/2 ground state. By X-ray spectroscopy and calculations, [3](1-) features a high-spin Co(II) center; the net S = 1/2 spin state arises after the Co electrons couple to both the O2(•-) and the aminyl radical on redox non-innocent (L(•))(2-). Dianion [1](2-) shows both nucleophilic and electrophilic catalytic reactivity upon activation of O2 due to the presence of both a high-energy, filled O2(-) π* orbital and an empty low-lying O2(-) π* orbital in [3](1-). PMID:26799113

  4. Synthesis and characterization of Cu(II), Co(II) and Ni(II) complexes of a number of sulfadrug azodyes and their application for wastewater treatment.

    PubMed

    El-Baradie, K; El-Sharkawy, R; El-Ghamry, H; Sakai, K

    2014-01-01

    The azodye ligand (HL(1)) was synthesized from the coupling of sulfaguanidine diazonium salt with 2,4-dihydroxy-benzaldehyde while the two ligands, HL(2) and HL(3), were prepared by the coupling of sulfadiazine diazonium salt with salicylaldehyde (HL(2)) and 2,4-dihydroxy-benzaldehyde (HL(3)). The prepared ligands were characterized by elemental analysis, IR, (1)H NMR and mass spectra. Cu(II), Co(II) and Ni(II) complexes of the prepared ligands have been synthesized and characterized by various spectroscopic techniques like IR, UV-Visible as well as magnetic and thermal (TG and DTA) measurements. It was found that all the ligands behave as a monobasic bidentate which coordinated to the metal center through the azo nitrogen and α-hydroxy oxygen atoms in the case of HL(1) and HL(3). HL(2) coordinated to the metal center through sulfonamide oxygen and pyrimidine nitrogen. The applications of the prepared complexes in the oxidative degradation of indigo carmine dye exhibited good catalytic activity in the presence of H2O2 as an oxidant. The reactions followed first-order kinetics and the rate constants were determined. The degradation reaction involved the catalytic action of the azo-dye complexes toward H2O2 decomposition, which can lead to the generation of HO radicals as a highly efficient oxidant attacking the target dye. The detailed kinetic studies and the mechanism of these catalytic reactions are under consideration in our group. PMID:24239761

  5. Reactivity of Hydride Bridges in High-Spin [3M-3(μ-H)] Clusters (M = FeII, CoII).

    PubMed

    Lee, Yousoon; Anderton, Kevin J; Sloane, Forrest T; Ermert, David M; Abboud, Khalil A; García-Serres, Ricardo; Murray, Leslie J

    2015-08-26

    The designed [3M-3(μ-H)] clusters (M = Fe(II), Co(II)) Fe3H3L (1-H) and Co3H3L (2-H) [where L(3-) is a tris(β-diketiminate) cyclophane] were synthesized by treating the corresponding M3Br3L complexes with KBEt3H. From single-crystal X-ray analysis, the hydride ligands are sterically protected by the cyclophane ligand, and these complexes selectively react with CO2 over other unsaturated substrates (e.g., CS2, Me3SiCCH, C2H2, and CH3CN). The reaction of 1-H or 2-H with CO2 at room temperature yielded Fe3(OCHO)(H)2L (1-CO2) or Co3(OCHO)(H)2L (2-CO2), respectively, which evidence the differential reactivity of the hydride ligands within these complexes. The analogous reactions at elevated temperatures revealed a distinct difference in the reactivity pattern for 2-H as compared to 1-H; Fe3(OCHO)3L (1-3CO2) was generated from 1-H, while 2-H afforded only 2-CO2.

  6. In situ generation of Co(II) by use of a solid-phase reactor in an FIA assembly for the spectrophotometric determination of penicillamine.

    PubMed

    Corominas, B Gómez-Taylor; Pferzschner, Julia; Icardo, M Catalá; Zamora, L Lahuerta; Martínez Calatayud, J

    2005-09-01

    A flow injection analysis (FIA) manifold for the determination of penicillamine in pharmaceutical preparations is proposed. The manifold includes a solid-phase reactor for the in situ production of the derivatizing reagent, Co(II) ion, which forms a coloured complex with penicillamine in an alkaline medium. The reactor is prepared by natural immobilization of cobalt carbonate on a polymer matrix, which endows it with a high mechanical and microbiological stability. The cobalt released by passage of a 5 x 10(-4) mol l(-1) sulphuric acid stream at a flow-rate of 2.3 ml min(-1) is merged with a volume of 314 microl of sample containing penicillamine in ammonium-ammonia buffer at pH 9.5 to measure the absorbance at 360 nm. Beer's law is obeyed over the penicillamine concentration range 5-60 mg l(-1). The limit of detection (LOD) of the method is 1 mg l(-1) and its throughput 70 samples h(-1).

  7. Coligand-regulated assembly, fluorescence, and magnetic properties of Co(II) and Cd(II) complexes with a non-coplanar dicarboxylate

    NASA Astrophysics Data System (ADS)

    Xin, Ling-Yun; Liu, Guang-Zhen; Ma, Lu-Fang; Wang, Li-Ya

    2013-10-01

    A non-coplanar dicarboxylate ndca (H2ndca=5-norbornene-2,3-dicarboxylic acid), combining with various dipyridyl-typed tectons, constructs six Cd(II)/Co(II) coordination polymers under hydrothermal conditions, namely [Co(ndca)(H2O)]n (1), {[Co(ndca)(bpe)(H2O)]·H2O}n (2), [Co(ndca)(bpa)0.5(H2O)]n (3), [Cd(ndca)(bpe)(H2O)]n (4), {[Cd(ndca)(bpa)(H2O)]·0.5H2O}n (5), and {[Cd(ndca)(bpp) (H2O)]·H2O}n (6) (bpe=1,2-di(4-pyridyl)ethylene, bpa=1,2-bi(4-pyridyl)ethane, and bpp=1,3-bis(4-pyridyl)propane). All these compounds contain various metal(II)-carboxylate motifs, including carboxylate binuclear (2, 4, 5), carboxylate chain (1, 6) and carboxylate layer (3), which are further extended by dipyridyl-typed coligands to afford a vast diversity of the structures with 2D pyknotic layers (1, 6), 2D open layer (5), 2D→3D interpenetrated networks (2,4), and 3D pillared-layer framework (3), respectively. In addition, fluorescent spectra of Cd(II) complexes and magnetic properties of Co(II) complexes are also given.

  8. Competitive Adsorption Study of CO2 and SO2 on CoII3[CoIII(CN)6]2 Using DRIFTS

    SciTech Connect

    Windisch, Charles F.; Thallapally, Praveen K.; McGrail, B. Peter

    2010-09-15

    Diffuse reflectance infrared Fourier transform spectroscopy was used to study the competitive adsorption of CO2 and SO2 on the cobalt Prussian blue analogue CoII3[CoIII(CN)6]2 at 298 K. Characteristic peaks for adsorbed CO2 and SO2 species were identified and their relative areas, measured simultaneously as a function of pressure at 298 K, varied in accordance with a Langmuir-Freundlich isotherm fitted to both gases in the low-coverage Henry’s Law limit. Evidence for co-adsorption of trace water was also obtained, as well as the apparent formation of an analogous cobalt nitroprusside compound as a reaction product under certain conditions. The several aspects of the adsorption of CO2 and SO2 on CoCo determined in this work point to an important role for real-time diffuse reflectance infrared measurements in adsorption studies, particularly in the case of competitive adsorption where the occurrence and fate of molecular-level markers arising from more than one adsorbed species can be monitored simultaneously. Depending on the application, this may more than offset certain quantitative limitations of the technique that confine measurements to a relatively narrow set of experimental conditions and demand careful consideration of the effects of sample preparation and treatment.

  9. DNA Binding, Cleavage and Antibacterial Activity of Mononuclear Cu(II), Ni(II) and Co(II) Complexes Derived from Novel Benzothiazole Schiff Bases.

    PubMed

    Vamsikrishna, Narendrula; Kumar, Marri Pradeep; Tejaswi, Somapangu; Rambabu, Aveli; Shivaraj

    2016-07-01

    A series of novel bivalent metal complexes M(L1)2 and M(L2)2 where M = Cu(II), Ni(II), Co(II) and L1 = 2-((benzo [d] thiazol-6-ylimino)methyl)-4-bromophenol [BTEMBP], L2 = 1-((benzo [d] thiazol-6-ylimino)methyl) naphthalen-2-ol [BTEMNAPP] were synthesized. All the compounds have been characterized by elemental analysis, SEM, Mass, (1)H NMR, (13)C NMR, UV-Vis, IR, ESR, spectral data and magnetic susceptibility measurements. Based on the analytical and spectral data four-coordinated square planar geometry is assigned to all the complexes. DNA binding properties of these complexes have been investigated by electronic absorption spectroscopy, fluorescence and viscosity measurements. It is observed that these binary complexes strongly bind to calf thymus DNA by an intercalation mode. DNA cleavage efficacy of these complexes was tested in presence of H2O2 and UV light by gel electrophoresis and found that all the complexes showed better nuclease activity. Finally the compounds were screened for antibacterial activity against few pathogens and found that the complexes have potent biocidal activity than their free ligands.

  10. Oxygen Activation by Co(II) and a Redox Non-Innocent Ligand: Spectroscopic Characterization of a Radical-Co(II)-Superoxide Complex with Divergent Catalytic Reactivity.

    PubMed

    Corcos, Amanda R; Villanueva, Omar; Walroth, Richard C; Sharma, Savita K; Bacsa, John; Lancaster, Kyle M; MacBeth, Cora E; Berry, John F

    2016-02-17

    Bimetallic (Et4N)2[Co2(L)2], (Et4N)2[1] (where (L)(3-) = (N(o-PhNC(O)(i)Pr)2)(3-)) reacts with 2 equiv of O2 to form the monometallic species (Et4N)[Co(L)O2], (Et4N)[3]. A crystallographically characterized analog (Et4N)2[Co(L)CN], (Et4N)2[2], gives insight into the structure of [3](1-). Magnetic measurements indicate [2](2-) to be an unusual high-spin Co(II)-cyano species (S = 3/2), while IR, EXAFS, and EPR spectroscopies indicate [3](1-) to be an end-on superoxide complex with an S = 1/2 ground state. By X-ray spectroscopy and calculations, [3](1-) features a high-spin Co(II) center; the net S = 1/2 spin state arises after the Co electrons couple to both the O2(•-) and the aminyl radical on redox non-innocent (L(•))(2-). Dianion [1](2-) shows both nucleophilic and electrophilic catalytic reactivity upon activation of O2 due to the presence of both a high-energy, filled O2(-) π* orbital and an empty low-lying O2(-) π* orbital in [3](1-).

  11. Co(II), Ni(II) and Cu(II) complexes with coumarin-8-yl Schiff-bases: Spectroscopic, in vitro antimicrobial, DNA cleavage and fluorescence studies

    NASA Astrophysics Data System (ADS)

    Patil, Sangamesh A.; Unki, Shrishila N.; Kulkarni, Ajaykumar D.; Naik, Vinod H.; Badami, Prema S.

    2011-09-01

    A new series of Co(II), Ni(II) and Cu(II) complexes of the type ML·2H 2O of Schiff-bases derived from m-substituted thiosemicarbazides and 8-acetyl-7-hydroxy-4-methylcoumarin have been synthesized and characterized by spectroscopic studies. Schiff-bases exhibit thiol-thione tautomerism wherein sulphur plays an important role in the coordination. The coordination possibility of the Schiff-bases towards metal ions have been proposed in the light of elemental analyses, spectral (IR, UV-vis, FAB-mass, ESR and fluorescence), magnetic and thermal studies. The low molar conductance values in DMF indicate that, the metal complexes are non-electrolytes. The cyclic voltammetric studies suggested that, the Cu(II) and Ni(II) complexes are of single electron transfer quasi-reversible nature. The Schiff-bases and its metal complexes have been evaluated for their in vitro antibacterial ( Escherichia coli, Staphilococcus aureus, Bascillus subtilis and Salmonella typhi) and antifungal activities ( Candida albicans, Cladosporium and Aspergillus niger) by MIC method. The Schiff-base I and its metal complexes exhibited DNA cleavage activity on isolated DNA of A. niger.

  12. Electrochemical Determination of Bisphenol A with Pencil Graphite Electrodes Modified with Co(II), Ni(II), Cu(II) and Fe(II) Phthalocyaninetetrasulfonates.

    PubMed

    Özcan, Levent; Altuntas, Muhammet; Büyüksagis, Aysel; Türk, Hayrettin; Yurdakal, Sedat

    2016-01-01

    Pencil graphite electrodes modified with Co(II), Ni(II), Cu(II) and Fe(II) metallophthalocyaninetetrasulfonates (MePcTSs) were investigated for an electrochemical determination of bisphenol A (BPA). The electrochemical performances of the modified electrodes for different pH values in phosphate and the Britton-Robinson buffers were determined by cyclic voltammetry; the electrode performances were better in the Britton-Robinson buffer. NiPcTS and CoPcTS modifications of the electrodes had remarkable enhancements on their performances. The differential pulse voltammetry parameters for the electrodes were optimized, and we found that the electrochemical response versus the concentration of BPA is linear from 5.0 × 10(-7) to 1.0 × 10(-5) M for the NiPcTS and CoPcTS modified electrodes. The detection limits of these modified electrodes are 2.9 × 10(-7) and 4.3 × 10(-7) M, respectively, and the effects of interfering species are less than 5%. The results show that NiPcTS and CoPcTS modified pencil graphite electrodes could be used for electrochemical determinations of BPA for analytical purposes. PMID:27506715

  13. Molecular systematics and phylogeography of Cebus capucinus (Cebidae, Primates) in Colombia and Costa Rica by means of the mitochondrial COII gene.

    PubMed

    Ruiz-Garcia, Manuel; Castillo, Maria Ignacia; Ledezma, Andrea; Leguizamon, Norberto; Sánchez, Ronald; Chinchilla, Misael; Gutierrez-Espeleta, Gustavo A

    2012-04-01

    We propose the first molecular systematic hypothesis for the origin and evolution of Cebus capucinus based on an analysis of 710 base pairs (bp) of the cytochrome c oxidase subunit II (COII) mitochondrial gene in 121 C. capucinus specimens sampled in the wild. The animals came from the borders of Guatemala and Belize, Costa Rica, and eight different departments of Colombia (Antioquia, Chocó, Sucre, Bolivar, Córdoba, Magdalena, Cauca, and Valle del Cauca). Three different and significant haplotype lineages were found in Colombia living sympatrically in the same departments. They all presented high levels of gene diversity but the third Colombian gene pool was determined likely to be the most ancestral lineage. The second Colombian mitochondrial (mt) haplogroup is likely the source of origin of the unique Central America mt haplogroup that was detected. Our molecular population genetics data do not agree with the existence of two well-defined subspecies in Central America (limitaneus and imitator). This Central America mt haplogroup showed significantly less genetic diversity than the Colombian mt haplogroups. All the C. capucinus analyzed showed evidence of historical population expansions. The temporal splits among these four C. capucinus lineages were related to the completion of the Panamanian land bridge as well as to climatic changes during the Quaternary Period. PMID:21455949

  14. Co(II), Ce(III) and UO 2(VI) bis-salicylatothiosemicarbazide complexes . Binary and ternary complexes, thermal studies and antimicrobial activity

    NASA Astrophysics Data System (ADS)

    El-Wahab, Z. H. Abd; Mashaly, Mahmoud M.; Salman, A. A.; El-Shetary, B. A.; Faheim, A. A.

    2004-10-01

    A series of new metal complexes of Co(II), Ce(III) and UO 2(VI), with the Schiff base ligand, H 2L, bis-salicylatothiosemicarbazide have been prepared in presence of different molar ratios of LiOH·H 2O as a deprotonating agent. Also, the ternary complexes were prepared by using 2-aminopyridine (2-Ampy) or oxalic acid (Ox) as a secondary ligand. All synthesized compounds were identified and confirmed by elemental analyses, molar conductivities, spectral (UV-Vis, IR, 1H NMR, mass) and magnetic moment measurements as well as TG-DSC technique. The changes in the selected vibrational absorption bands in IR and NMR spectra of the Schiff base ligand upon coordination indicate that, the ligand behaves as a neutral, monoanionic and/or dianionic tetradentate manner with ONNO donor sites. Conductance measurements suggest the non-electrolytic and 1:1 electrolytic nature of the metal complexes. Thermal studies suggest a mechanism for degradation of the metal complexes as function of temperature supporting the chelation modes, moreover, show the possibility of obtaining new complexes pyrolytically in the solid state which cannot be synthesized from solution. Antimicrobial screening of the free ligand and its binary complexes showed that, the free ligand and some metal complexes possess antimicrobial activities towards four type of bacteria and five types of fungi and these results were compared with eleven type of known antibiotics.

  15. Supramolecular complexes of Co(II), Ni(II) and Zn(II) p-hydroxybenzoates with caffeine: Synthesis, spectral characterization and crystal structure

    NASA Astrophysics Data System (ADS)

    Taşdemir, Erdal; Özbek, Füreya Elif; Sertçelik, Mustafa; Hökelek, Tuncer; Çelik, Raziye Çatak; Necefoğlu, Hacali

    2016-09-01

    Three novel complexes Co(II), Ni(II) and Zn(II) containing p-hydroxybenzoates and caffeine ligands were synthesized and characterized by elemental analysis, FT-IR and UV-vis Spectroscopy, molar conductivity and single crystal X-ray diffraction methods. The thermal properties of the synthesized complexes were investigated by TGA/DTA. The general formula of the complexes is [M(HOC6H4COO)2(H2O)4]·2(C8H10N4O2)·8H2O (where: M: Co, Ni and Zn). The IR studies showed that carboxylate groups of p-hydroxybenzoate ligands have monodentate coordination mode. The M2+ ions are octahedrally coordinated by two p-hydroxybenzoate ligands, four water molecules leading to an overall MO6 coordination environment. The medium-strength hydrogen bondings involving the uncoordinated caffeine ligands and water molecules, coordinated and uncoordinated water molecules and p-hydroxybenzoate ligands lead to three-dimensional supramolecular networks in the crystal structures.

  16. MtDNA COI-COII marker and drone congregation area: an efficient method to establish and monitor honeybee (Apis mellifera L.) conservation centres.

    PubMed

    Bertrand, Bénédicte; Alburaki, Mohamed; Legout, Hélène; Moulin, Sibyle; Mougel, Florence; Garnery, Lionel

    2015-05-01

    Honeybee subspecies have been affected by human activities in Europe over the past few decades. One such example is the importation of nonlocal subspecies of bees which has had an adverse impact on the geographical repartition and subsequently on the genetic diversity of the black honeybee Apis mellifera mellifera. To restore the original diversity of this local honeybee subspecies, different conservation centres were set up in Europe. In this study, we established a black honeybee conservation centre Conservatoire de l'Abeille Noire d'Ile de France (CANIF) in the region of Ile-de-France, France. CANIF's honeybee colonies were intensively studied over a 3-year period. This study included a drone congregation area (DCA) located in the conservation centre. MtDNA COI-COII marker was used to evaluate the genetic diversity of CANIF's honeybee populations and the drones found and collected from the DCA. The same marker (mtDNA) was used to estimate the interactions and the haplotype frequency between CANIF's honeybee populations and 10 surrounding honeybee apiaries located outside of the CANIF. Our results indicate that the colonies of the conservation centre and the drones of the DCA show similar stable profiles compared to the surrounding populations with lower level of introgression. The mtDNA marker used on both DCA and colonies of the conservation centre seems to be an efficient approach to monitor and maintain the genetic diversity of the protected honeybee populations. PMID:25335970

  17. Synthesis, characterization, biological activity of binuclear Co(II), Cu(II) and mononuclear Ni(II) complexes of bulky multi-dentate thiosemicarbazide

    NASA Astrophysics Data System (ADS)

    El-Gammal, O. A.; Abd Al-Gader, I. M.; El-Asmy, A. A.

    2014-07-01

    The chelation behavior of 9,10-dihydro-9,10-ethanoanthracene-11,12-dicarbonyl) bis (N-ethylhydrazine-1-carbothioamide) (H6ETS)(1) towards Co2+, Ni2+and Cu2+ have been studied. The spectral data revealed that the ligand acts as a bi- and/or mono-negative multi-dentate. The isolated Ni(II) and Cu(II) complexes are square-planar while the Co(II) is tetrahedral. EPR spectrum of Cu(II) complex confirmed simulated an axial spin-Hamiltonian exhibiting a four-line pattern with nitrogen super-hyperfine couplings originating from imine hydrazinic nitrogen atoms and possess a significant amount of tetrahedral distortion leading to a pseudo-square-planar geometry with unpaired electron has d ground state. Also, the thermal behavior and kinetic parameters were determined. Furthermore, the title compounds were investigated for their antibacterial activity using inhibition zone diameter and for DNA degradation, superoxide-scavenging activity as well as hydroxyl radicals that generated by the oxidation of cytochrome c in L-ascorbic acid/CuSO4-cytochrome c system.

  18. Synthesis and characterization of Cu(II), Co(II) and Ni(II) complexes of a number of sulfadrug azodyes and their application for wastewater treatment

    NASA Astrophysics Data System (ADS)

    El-Baradie, K.; El-Sharkawy, R.; El-Ghamry, H.; Sakai, K.

    2014-03-01

    The azodye ligand (HL1) was synthesized from the coupling of sulfaguanidine diazonium salt with 2,4-dihydroxy-benzaldehyde while the two ligands, HL2 and HL3, were prepared by the coupling of sulfadiazine diazonium salt with salicylaldehyde (HL2) and 2,4-dihydroxy-benzaldehyde (HL3). The prepared ligands were characterized by elemental analysis, IR, 1H NMR and mass spectra. Cu(II), Co(II) and Ni(II) complexes of the prepared ligands have been synthesized and characterized by various spectroscopic techniques like IR, UV-Visible as well as magnetic and thermal (TG and DTA) measurements. It was found that all the ligands behave as a monobasic bidentate which coordinated to the metal center through the azo nitrogen and α-hydroxy oxygen atoms in the case of HL1 and HL3. HL2 coordinated to the metal center through sulfonamide oxygen and pyrimidine nitrogen. The applications of the prepared complexes in the oxidative degradation of indigo carmine dye exhibited good catalytic activity in the presence of H2O2 as an oxidant. The reactions followed first-order kinetics and the rate constants were determined. The degradation reaction involved the catalytic action of the azo-dye complexes toward H2O2 decomposition, which can lead to the generation of HOrad radicals as a highly efficient oxidant attacking the target dye. The detailed kinetic studies and the mechanism of these catalytic reactions are under consideration in our group.

  19. DNA cleavage, antimicrobial, spectroscopic and fluorescence studies of Co(II), Ni(II) and Cu(II) complexes with SNO donor coumarin Schiff bases

    NASA Astrophysics Data System (ADS)

    Patil, Sangamesh A.; Naik, Vinod H.; Kulkarni, Ajaykumar D.; Badami, Prema S.

    2010-01-01

    A series of Co(II), Ni(II) and Cu(II) complexes of the type ML 2 have been synthesized with Schiff bases derived from methylthiosemicarbazone and 5-formyl-6-hydroxy coumarin/8-formyl-7-Hydroxy-4-methylcoumarin. The complexes are insoluble in common organic solvents but soluble in DMF and DMSO. The measured molar conductance values in DMF indicate that, the complexes are non-electrolytes in nature. In view of analytical, spectral (IR, UV-vis, ESR, FAB-mass and fluorescence), magnetic and thermal studies, it has been concluded that, all the metal complexes possess octahedral geometry in which ligand is coordinated to metal ion through azomethine nitrogen, thione sulphur and phenolic oxygen atom via deprotonation. The redox behavior of the metal complexes was investigated by using cyclic voltammetry. The Schiff bases and their complexes have been screened for their antibacterial ( Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi) and antifungal activities ( Aspergillus niger, Aspergillus flavus and Cladosporium) by Minimum Inhibitory Concentration method. The DNA cleavage is studied by agarose gel electrophoresis method.

  20. Synthesis, DFT Calculation, and Antimicrobial Studies of Novel Zn(II), Co(II), Cu(II), and Mn(II) Heteroleptic Complexes Containing Benzoylacetone and Dithiocarbamate.

    PubMed

    Ekennia, Anthony C; Onwudiwe, Damian C; Olasunkanmi, Lukman O; Osowole, Aderoju A; Ebenso, Eno E

    2015-01-01

    Heteroleptic complexes of zinc(II), copper(II), manganese(II), and cobalt(II) of the types [MLL'(H2O)2]·nH2O and [MLL']·nH2O have been synthesized using sodium N-methyl-N-phenyldithiocarbamate (L) and benzoylacetone (L'). The metal complexes were characterized by elemental analysis, electrical conductance, magnetic susceptibility, infrared (IR), and UV-visible spectroscopic studies. The electrical conductance measurements revealed the nonelectrolytic nature of the synthesized complexes. The results of the elemental analyses, magnetic susceptibility measurements, and electronic spectra inferred that the Zn(II) complex adopted a four-coordinate geometry while the Co(II), Cu(II), and Mn(II) complexes assumed octahedral geometries. The IR spectra showed that the metal ions coordinated with the ligands via the S- and O-donor atoms. The geometry, electronic, and thermodynamic parameters of the complexes were obtained from density functional theory (DFT) calculations. The spin density distributions, relative strength of H-bonds, and thermodynamic parameters revealed that the order of stability of the metal complexes is Mn < Co < Cu > Zn. The agar diffusion methods were used to study the antimicrobial activity of the complexes against two Gram positive bacteria (S. aureus and S. pneumoniae), one Gram negative bacterium (E. coli), and two fungi organisms (A. niger and A. candida) and the complexes showed a broad spectrum of activities against the microbes. PMID:26681931

  1. Suppressing of slow magnetic relaxation in tetracoordinate Co(II) field-induced single-molecule magnet in hybrid material with ferromagnetic barium ferrite.

    PubMed

    Nemec, Ivan; Herchel, Radovan; Trávníček, Zdeněk

    2015-01-01

    The novel field-induced single-molecule magnet based on a tetracoordinate mononuclear heteroleptic Co(II) complex involving two heterocyclic benzimidazole (bzi) and two thiocyanido ligands, [Co(bzi)2(NSC)2], (CoL4), was prepared and thoroughly characterized. The analysis of AC susceptibility data resulted in the spin reversal energy barrier U = 14.7 cm(-1), which is in good agreement with theoretical prediction, U(theor). = 20.2 cm(-1), based on axial zero-field splitting parameter D = -10.1 cm(-1) fitted from DC magnetic data. Furthermore, mutual interactions between CoL4 and ferromagnetic barium ferrite BaFe12O19 (BaFeO) in hybrid materials resulted in suppressing of slow relaxation of magnetization in CoL4 for 1:2, 1:1 and 2:1 mass ratios of CoL4 and BaFeO despite the lack of strong magnetic interactions between two magnetic phases. PMID:26039085

  2. N-[3a-(4-Bromo-phen-yl)-8b-hy-droxy-6,8-dimeth-oxy-3-phenyl-2,3,3a,8b-tetra-hydro-1H-cyclo-penta-[b]benzofuran-1-yl]formamide monohydrate.

    PubMed

    Aubert, Emmanuel; Thuaud, Frédéric; Ribeiro, Nigel; Désaubry, Laurent; Espinosa, Enrique

    2013-01-01

    In the title compound, C26H24BrNO5·H2O, a synthetic analogue of natural flavagline, the cyclo-pentane ring adopts an envelope conformation (the flap atom bearing the phenyl group) and the vicinal phenyl and bromo-phenyl groups are slightly shifted relative to each other [CPh-C-C-CPhBr = 36.3 (2)°]. Intra-molecular N-H⋯O and C-H⋯O hydrogen bonds form S(5) motifs. In the crystal, the organic and the water mol-ecules are linked by an O-H⋯O hydrogen bond. Pairs of organic and water mol-ecules, located about inversion centers, inter-act through O-H⋯O hydrogen bonds, forming R4(4)(20) and R4(4)(26) motifs, which together lead to C2(2)(9) motifs. The crystal packing is also characterized by N-H⋯O and C-H⋯O hydrogen bonds between neighbouring organic mol-ecules, forming R2(2)(10) and R2(2)(18) motifs, respectively. PMID:23476436

  3. Dimethyl 2-[23-oxo-22,24-diphenyl-8,11,14-trioxa-25-aza-tetra-cyclo-[19.3.1.0(2,7).0(15,20)]penta-cosa-2,4,6,15(20),16,18-hexaen-25-yl]but-2-enedioate.

    PubMed

    Anh, Le Tuan; Hieu, Truong Hong; Soldatenkov, Anatoly T; Soldatova, Svetlana A; Khrustalev, Victor N

    2012-05-01

    The title compound, C(39)H(37)NO(8), is a product of the Michael addition of the cyclic secondary amine subunit of aza-14-crown-4 ether to dimethyl acetyl-enedicarboxyl-ate. The piperidinone ring exhibits a distorted chair conformation and the dimethyl acetyl-enedicarboxyl-ate fragment has a cis configuration with a dihedral angle of 56.61 (5)° between the two carboxyl-ate groups. The crystal packing is stabilized by the weak C-H⋯O hydrogen bonds. PMID:22590276

  4. Dimethyl 2-[23-oxo-22,24-diphenyl-8,11,14-trioxa-25-aza­tetra­cyclo­[19.3.1.02,7.015,20]penta­cosa-2,4,6,15(20),16,18-hexaen-25-yl]but-2-enedioate

    PubMed Central

    Anh, Le Tuan; Hieu, Truong Hong; Soldatenkov, Anatoly T.; Soldatova, Svetlana A.; Khrustalev, Victor N.

    2012-01-01

    The title compound, C39H37NO8, is a product of the Michael addition of the cyclic secondary amine subunit of aza-14-crown-4 ether to dimethyl acetyl­enedicarboxyl­ate. The piperidinone ring exhibits a distorted chair conformation and the dimethyl acetyl­enedicarboxyl­ate fragment has a cis configuration with a dihedral angle of 56.61 (5)° between the two carboxyl­ate groups. The crystal packing is stabilized by the weak C—H⋯O hydrogen bonds. PMID:22590276

  5. 3,10,14,21-Tetra-kis(4-meth-oxy-phen-yl)penta-cyclo-[11.8.0.0(2,11).0(4,9).0(15,20)]henicosa-1(21),2,4(9),5,7,10,13,15(20),16,18-decaen-12-one chloro-form monosolvate.

    PubMed

    Gopinath, S; Narayanan, P; Sethusankar, K; Nandakumar, Meganathan; Mohanakrishnan, Arasambattu K

    2014-08-01

    The asymmetric unit of the title compound, C49H36O6·CHCl3, contains half an organic mol-ecule, the complete mol-ecule being generated by the operation of a crystallographic twofold rotation axis, and half a highly disordered chloro-form mol-ecule. The contribution to the diffraction pattern of the latter was removed using the program SQUEEZE in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]; the unit-cell characteristics take into account the presence of CHCl3. The dihedral angles between the planes of the naphthalene ring system and the meth-oxy-benzene rings are 71.05 (7) (syn to the central C=O group) and 57.27 (6)° (anti to the central C=O group). In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating C(12) chains running parallel to the b axis. PMID:25249919

  6. Di-μ-cyanido-tetra­cyanido(5,5,7,12,12,14-hexa­methyl-1,4,8,11-tetra­aza­cyclo­tetra­decane)[N-(quinolin-8-yl)quinoline-2-carboxamidato]diiron(III)nickel(II) 2.07-hydrate

    PubMed Central

    Yang, Yuqi; Zhou, Hongbo; Shen, Xiaoping

    2013-01-01

    The asymmetric unit of the title complex, [Fe2Ni(C19H12N3O)2(CN)6(C16H36N4)]·2.07H2O, contains one [Fe(qcq)(CN)3]− anion, half a [Ni(teta)]2+ cation and two partially occupied inter­stitial water mol­ecules [qcq− is the N-(quinolin-8-yl)quinoline-2-carboxamidate anion and teta is 5,5,7,12,12,14-hexa­methyl-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne]. In the complex mol­ecule, two [Fe(qcq)(CN)3]− anions additionally coordinate the central [Ni(teta)]2+ cation through cyanide groups in a trans mode, resulting in a trinuclear structure with the Ni2+ cation lying on an inversion centre. The two inter­stitial water mol­ecules are partially occupied, with occupancy factors of 0.528 (10) and 0.506 (9). O—H⋯O and O—H⋯N hydrogen bonding involving the two lattice water molecules and the carbonyl function and a teta N atom in an adjacent cluster leads to the formation of layers extending parallel to (010). PMID:23723777

  7. 40 CFR 721.1800 - 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1800 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as...

  8. 40 CFR 721.1800 - 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1800 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as...

  9. 40 CFR 721.1800 - 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1800 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as...

  10. 40 CFR 721.9530 - Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) ester of cycloalkyl spir-o-ke-tal. 721.9530 Section 721.9530 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.9530 Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester...) The chemical substance identified generically as bis(2,2,6,6-tetramethyl pi-per-idin-yl) ester of...

  11. 40 CFR 721.4040 - Glycols, polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Glycols, polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. 721.4040 Section 721.4040 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant...

  12. The meloxicam complexes of Co(II) and Zn(II): Synthesis, crystal structures, photocleavage and in vitro DNA-binding

    NASA Astrophysics Data System (ADS)

    Sanatkar, Tahereh Hosseinzadeh; Hadadzadeh, Hassan; Simpson, Jim; Jannesari, Zahra

    2013-10-01

    Two neutral mononuclear complexes of Co(II) and Zn(II) with the non-steroidal anti-inflammatory drug meloxicam (H2mel, 4-hydroxy-2-methyl-N-(5-methyl-2-thiazolyl)-2H-1,2-benzothiazine-3-carboxammide-1,1-dioxide), [Co(Hmel)2(EtOH)2] (1), and [Zn(Hmel)2(EtOH)2] (2), were synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopy and their solid-state structures were studied by single-crystal diffraction. The complexes have a distorted octahedral geometry around the metal atom. The experimental data indicate that the meloxicam acts as a deprotonated bidentate ligand (through the amide oxygen and the nitrogen atom of the thiazolyl ring) in the complexes, and a strong intramolecular hydrogen bond between the amide N-H function and the enolate O atom stabilizes the ZZZ conformation of meloxicam ligands. Absorption, fluorescence spectroscopy and cyclic voltammetry have been used to investigate the binding of the complexes with fish sperm DNA (FS-DNA). Additionally, the photocleavage studies have been also used to investigate the binding of the complexes with plasmid DNA. The interaction of the complexes with DNA was monitored by a blue shift and hyperchromism in the UV-Vis spectra attributed to an electrostatic binding mode. A competitive study with ethidium bromide (EB) has shown that the complexes can displace the DNA-bound EB indicating that they bind to DNA in strong competition with EB. The experimental results show that the complexes can cleave pUC57 plasmid DNA.

  13. Antibacterial studies, DNA oxidative cleavage, and crystal structures of Cu(II) and Co(II) complexes with two quinolone family members, ciprofloxacin and enoxacin.

    PubMed

    Jiménez-Garrido, N; Perelló, L; Ortiz, R; Alzuet, G; González-Alvarez, M; Cantón, E; Liu-González, M; García-Granda, S; Pérez-Priede, M

    2005-03-01

    Nine coordination compounds of Cu(II) and Co(II) with Ciprofloxacin (HCp) and Enoxacin (HEx) as ligands have been prepared and characterized. Single crystal structural determinations of [Cu(HCp)2(ClO4)2].6H2O (1) and [Co(HEx)2(Ex)]Cl.2CH(3)OH.12H2O (4) are reported. The crystal of 1 is composed of [Cu(HCp)2(ClO4)2] units with the two perchlorate anions semicoordinated, and uncoordinated water molecules. The copper ion, at a crystallographic inversion centre, is in a tetragonally distorted octahedral environment. The structure of 4 consists of cationic monomeric [Co(HEx)2(Ex)]+ units, chloride anions, and uncoordinated methanol and water molecules. The complex is six-coordinate, with a slightly distorted octahedral environment around the metal centre. Some complexes of ciprofloxacin and enoxacin were screened for their activity against several bacteria, showing activity similar to that of the corresponding free ligands. All compounds tested were more active against Gram-negative bacteria than against Gram-positive bacteria. Ciprofloxacin hydrochloride and its complexes were more active than enoxacin and its complexes. In addition, the bactericidal studies against Staphylococcus aureus ATCC 25923 reveal that one complex exhibits the "paradoxical effect" (diminution in the number of bacteria killed at high drug concentration), which has been described and related to the mechanism of action of quinolones, but three other complexes do not, suggesting different mechanisms of bactericidal action. The ability of Cu(HCp)2(NO3)2.6H2O to cleave DNA has been determined. The results show that the complex behaves as an efficient chemical nuclease with ascorbate/hydrogen peroxide activation. Mechanistic studies using different inhibiting reagents reveal that hydroxyl radicals are involved in the DNA scission process mediated by this compound.

  14. Coligand-regulated assembly, fluorescence, and magnetic properties of Co(II) and Cd(II) complexes with a non-coplanar dicarboxylate

    SciTech Connect

    Xin, Ling-Yun; Liu, Guang-Zhen; Ma, Lu-Fang; Wang, Li-Ya

    2013-10-15

    A non-coplanar dicarboxylate ndca (H{sub 2}ndca=5-norbornene-2,3-dicarboxylic acid), combining with various dipyridyl-typed tectons, constructs six Cd(II)/Co(II) coordination polymers under hydrothermal conditions, namely [Co(ndca)(H{sub 2}O)]{sub n} (1), ([Co(ndca)(bpe)(H{sub 2}O)]·H{sub 2}O){sub n} (2), [Co(ndca)(bpa){sub 0.5}(H{sub 2}O)]{sub n} (3), [Cd(ndca)(bpe)(H{sub 2}O)]{sub n} (4), ([Cd(ndca)(bpa)(H{sub 2}O)]·0.5H{sub 2}O){sub n} (5), and ([Cd(ndca)(bpp) (H{sub 2}O)]·H{sub 2}O){sub n} (6) (bpe=1,2-di(4-pyridyl)ethylene, bpa=1,2-bi(4-pyridyl)ethane, and bpp=1,3-bis(4-pyridyl)propane). All these compounds contain various metal(II)–carboxylate motifs, including carboxylate binuclear (2, 4, 5), carboxylate chain (1, 6) and carboxylate layer (3), which are further extended by dipyridyl-typed coligands to afford a vast diversity of the structures with 2D pyknotic layers (1, 6), 2D open layer (5), 2D→3D interpenetrated networks (2,4), and 3D pillared-layer framework (3), respectively. In addition, fluorescent spectra of Cd(II) complexes and magnetic properties of Co(II) complexes are also given. - Graphical abstract: Six various cadmium(II)/cobalt(II)–organic frameworks were constructed by 5-norbornene-2,3-dicarboxylic acid and different bis(pyridine) rod-like tectons, and Cd (II) complexes exhibit blue–violet emissions, whereas Co (II) complexes show antiferromagnetic behaviours. Display Omitted.

  15. Synthesis, characterization and in vitro anticancer activity of 18-membered octaazamacrocyclic complexes of Co(II), Ni(II), Cd(II) and Sn(II)

    NASA Astrophysics Data System (ADS)

    Kareem, Abdul; Zafar, Hina; Sherwani, Asif; Mohammad, Owais; Khan, Tahir Ali

    2014-10-01

    An effective series of 18 membered octaazamacrocyclic complexes of the type [MLX2], where X = Cl or NO3 have been synthesized by template condensation reaction of oxalyl dihydrazide with dibenzoylmethane and metal salt in 2:2:1 molar ratio. The formation of macrocyclic framework, stereochemistry and their overall geometry have been characterized by various physico-chemical studies viz., elemental analysis, electron spray ionization-mass spectrometry (ESI-MS), I.R, UV-Vis, 1H NMR, 13C NMR spectroscopy, X-ray diffraction (XRD) and TGA/DTA studies. These studies suggest formation of octahedral macrocyclic complexes of Co(II), Ni(II), Cd(II) and Sn(II). The molar conductance values suggest nonelectrolytic nature for all the complexes. Thermogravimatric analysis shows that all the complexes are stable up to 600 °C. All these complexes have been tested against different human cancer cell lines i.e. human hepatocellular carcinoma (Hep3B), human cervical carcinoma (HeLa), human breast adenocarcinoma (MCF7) and normal cells (PBMC). The newly synthesized 18-membered octaazamacrocyclic complexes during in vitro anticancer evaluation, displayed moderate to good cytotoxicity on liver (Hep3B), cervical (HeLa) and breast (MCF7) cancer cell lines, respectively. The most effective anticancer cadmium complex (C34H28N10CdO10) was found to be active with IC50 values, 2.44 ± 1.500, 3.55 ± 1.600 and 4.82 ± 1.400 in micro-molar on liver, cervical and breast cancer cell lines, respectively.

  16. Crystal structure of bis­(2-amino-5-chloro­pyridinium) tetra­chlorido­cobaltate(II)

    PubMed Central

    Mghandef, Marwa; Boughzala, Habib

    2015-01-01

    The title salt, (C5H6ClN2)2[CoCl4], was synthesized by slow evaporation of an aqueous solution at room temperature. The asymmetric unit consists of two essentially planar (C5H6ClN2)+ cations [maximum deviations = 0.010 (3) and 0.014 (3) Å] that are nearly perpendicular to each other [dihedral angle = 84.12 (7)°]. They are bonded through N—H⋯Cl hydrogen bonds to distorted [CoCl4]2− tetra­hedra, leading to the formation of undulating layers parallel to (100). The structure is isotypic with the Zn analogue [Kefi et. al (2011). Acta Cryst. E67, m355–m356.] PMID:25995878

  17. The influence of a solvent on the aggregation of ruthenium(II) tetra-15-crown-5-phthalocyaninate

    NASA Astrophysics Data System (ADS)

    Grishina, A. D.; Zolotarevskii, V. I.; Gorbunova, Yu. G.; Pereshivko, L. Ya.; Enakieva, Yu. Yu.; Krivenko, T. V.; Savel'Ev, V. V.; Vannikov, A. V.; Tsivadze, A. Yu.

    2009-11-01

    The images of ensembles of ruthenium(II) complexes with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules, (R4Pc)Ru(TED)2, obtained on an atomic force microscope were analyzed. A comparison with the X-ray structure analysis data was performed to estimate the number and mutual arrangement (architecture) of molecules in supramolecular aggregates depending on the nature of the solvent and the temperature of solutions before casting. Storage at room temperature or heating of a solution of the complex in tetrachloroethane caused the formation of stable supramolecular “wires” 600 nm or more long. The z-scanning method was used to study the third-order nonlinear optical characteristics of solutions of the (R4Pc)Ru(TED)2 complex in tetrachloroethane.

  18. Surface-Enhanced Raman Spectra of Tetra(4-Sulfonatophenyl)Porphyrin on the Surface of Plasmonic Silver Films

    NASA Astrophysics Data System (ADS)

    Gogoleva, S. D.; Lavysh, A. V.; Motevich, I. G.; Askirka, V. F.; Strekal, N. D.; Sheinin, V. B.; Koifman, O. I.; Zenkevich, E. I.; Maskevich, S. A.

    2016-05-01

    Absorption and Raman spectra of the tetra(4-sulfonatophenyl)porphyrin (TSPP) zwitterion in aqueous solutions under conditions at which porphyrin nanotubes (PNT) form (pH 1) are presented. TSPP was immobilized on the surface of plasmonic silver films (PSF) via quick transfer of a suspension of the molecules into a solution at pH 5 and onto the film surface in order to avoid degrading the film. Images of PNT and spheroidal TSPP aggregates on the PSF surface were visualized using confocal microscopy. Spatially resolved surface-enhanced Raman spectra (SERS) of these objects were recorded. Differences in SERS of PNT and TSPP globular aggregates are discussed based on quantum-chemical calculations of TSPP vibrational spectra. Vibrational bands sensitive to the tube-spherulite transition are found.

  19. Synthesis of tetra-substituted imidazoles and 2-imidazolines by Ni(0)-catalyzed dehydrogenation of benzylic-type imines.

    PubMed

    Tlahuext-Aca, Adrian; Hernández-Fajardo, Oscar; Arévalo, Alma; García, Juventino J

    2014-11-14

    Ni(0)-catalyzed dehydrogenation of benzylic-type imines was performed to yield asymmetrical tetra-substituted imidazoles and 2-imidazolines. This was achieved with a single operational step while maintaining good selectivity and atom economy. The catalytic system shows low to moderate tolerance for fluoro-, trifluoromethyl-, methyl-, and methoxy-substituted benzylic-type imines. In addition, the substitution pattern at the N-heterocyclic products was easily controlled by the appropriate selection of R-groups in the starting organic substrates. Based on experimental observations, we propose a reaction mechanism in which benzylic C(sp(3))-H bond activation and insertion steps play pivotal roles in this nickel-catalyzed organic transformation. PMID:25232889

  20. Crystal structure of catena-poly[N,N,N',N'-tetra-methyl-guanidinium [(chlorido-cadmate)-di-μ-chlorido

    PubMed

    Ndiaye, Mamadou; Samb, Abdoulaye; Diop, Libasse; Maris, Thierry

    2016-01-01

    In the structure of the title salt, {(C5H14N3)[CdCl3]} n , the Cd(II) atom of the complex anion is five-coordinated by one terminal and four bridging Cl atoms. The corresponding coordination polyhedron is a distorted trigonal bipyramid, with Cd-Cl distances in the range 2.4829 (4)-2.6402 (4) Å. The bipyramids are condensed into a polyanionic zigzag chain extending parallel to [101]. The tetra-methyl-guanidinium cations are situated between the polyanionic chains and are linked to them through N-H⋯Cl hydrogen bonds, forming a layered network parallel to (010). PMID:26870572

  1. N,N′-Bis(2-aza­niumylbenz­yl)ethane-1,2-diaminium tetra­chloride

    PubMed Central

    Garza Rodríguez, Luis Ángel; Bernès, Sylvain; Elizondo Martínez, Perla; Nájera Martínez, Blanca; Pérez Rodríguez, Nancy

    2011-01-01

    The title compound, C16H26N4 4+·4Cl−, is based on a fully protonated tetra­amine. In the cation, both benzene rings are connected by an all-trans chain, and the rings are almost parallel, with an angle between the mean planes of 8.34 (12)°. The benzene rings are arranged in such a way that the NH3 + substituents are oriented cis with respect to the central chain. This arrangement is a consequence of multiple N—H⋯Cl hydrogen bonds, involving all N—H groups in the cation and the four independent Cl− anions. These contacts have strengths ranging from weak to strong (based on H⋯Cl separations), and generate a complex three-dimensional crystal structure with no preferential crystallographic orientation for the contacts. PMID:22199749

  2. Redistribution of meta-tetra(hydroxyphenyl)chlorin (m-THPC) from conventional and PEGylated liposomes to biological substrates.

    PubMed

    Reshetov, Vadzim; Kachatkou, Dzmitry; Shmigol, Tatiana; Zorin, Vladimir; D'Hallewin, Marie-Ange; Guillemin, Francois; Bezdetnaya, Lina

    2011-06-01

    We used the phenomenon of previously described photoinduced fluorescence quenching and fluorescence polarization to evaluate the transfer of meta-tetra(hydroxyphenyl)chlorin (m-THPC) from commercial high-drug load liposomes to plasma proteins and model membranes. Fluorescence quenching of m-THPC in liposomes by iodide indicates that part of m-THPC in PEGylated liposomes is localized in the PEG shell, while the rest is bound to the lipid bilayer. It was shown that the two molecule pools in the commercial PEGylated liposomal formulation Fospeg® condition the characteristics of the m-THPC release kinetics. A substantial percentage of m-THPC from Fospeg® is released much faster than from the conventional liposomal formulation Foslip®. Using the technique of resonance light scattering, it was shown that partial m-THPC aggregation is present in liposomes with very high drug loads, higher in PEGylated liposomes compared to conventional ones.

  3. Excited state dynamics of metastable phthalocyanine-tetrasulfonate tetra-anions probed by pump/probe photoelectron spectroscopy

    SciTech Connect

    Ehrler, Oli T.; Yang Jiping; Sugiharto, Albert B.; Unterreiner, Andreas N.; Kappes, Manfred M.

    2007-11-14

    Femtosecond time-resolved pump-probe photoelectron spectroscopy was used to study elementary relaxation processes occurring in isolated phthalocyanine-tetrasulfonate tetra-anions ([MPc(SO{sub 3}){sub 4}]{sup 4-}, M=Cu,Ni, and ''free-base'' [H{sub 2}Pc(SO{sub 3}){sub 4}]{sup 4-}) following Q band excitation by one-photon absorption at 775 nm. Whereas the Cu and Ni systems decay rapidly by means of internal conversion without electron loss, the free-base phthalocyanine primarily undergoes excited state tunneling electron emission. This reflects less efficient coupling to lower lying states within the corresponding spin manifold. Results are interpreted in terms of (time-dependent) density functional theory calculations of ground and electronically excited states and kinetically modeled to yield the associated rates.

  4. 3,4,7,8-Tetra­methyl-1,10-phenanthrolin-1-ium nitrate monohydrate

    PubMed Central

    Zhang, Ke-Jie; Zhang, Yan-Fang

    2012-01-01

    In the crystal of the title compound, C16H17N2 +·NO3 −·H2O, the tetra­methyl-1,10-phenanthrolinium cations, nitrate anions and lattice water mol­ecules are all located on a mirror plane with the methyl H atoms of the cation equally disordered over two sites about the mirror plane. The cation, anion and water mol­ecule are linked by O—H⋯O and N—H⋯O hydrogen bonds into a sheet parallel to the bc plane. π–π stacking between phenanthroline ring systems is observed in the crystal structure, the centroid–centroid distance being 3.4745 (6) Å. PMID:22719684

  5. 4',4‴,7,7″-tetra-O-methylcupressuflavone inhibits seed germination of Lactuca sativa.

    PubMed

    DeForest, Jacob C; Du, Lin; Joyner, P Matthew

    2014-04-25

    Biflavonoids have been isolated from a wide variety of plant species, but little is known about their native biological functions. Here we report a possible ecological role for biflavonoids by describing the isolation of the biflavonoid 4',4‴,7,7″-tetra-O-methylcupressuflavone (1) from Araucaria columnaris and its inhibitory effect on seed germination. Compound 1 was isolated from needles of a single A. columnaris specimen and inhibited germination of Lactuca sativa seeds in a culture-dish assay; it was also detected in soil samples under the canopy where reduced germination was observed, but not in a location away from the canopy where germination was uninhibited. PMID:24628372

  6. The mechanism of color change in the neon tetra fish: a light-induced tunable photonic crystal array.

    PubMed

    Gur, Dvir; Palmer, Benjamin A; Leshem, Ben; Oron, Dan; Fratzl, Peter; Weiner, Steve; Addadi, Lia

    2015-10-12

    The fresh water fish neon tetra has the ability to change the structural color of its lateral stripe in response to a change in the light conditions, from blue-green in the light-adapted state to indigo in the dark-adapted state. The colors are produced by constructive interference of light reflected from stacks of intracellular guanine crystals, forming tunable photonic crystal arrays. We have used micro X-ray diffraction to track in time distinct diffraction spots corresponding to individual crystal arrays within a single cell during the color change. We demonstrate that reversible variations in crystal tilt within individual arrays are responsible for the light-induced color variations. These results settle a long-standing debate between the two proposed models, the "Venetian blinds" model and the "accordion" model. The insight gained from this biogenic light-induced photonic tunable system may provide inspiration for the design of artificial optical tunable systems. PMID:25914222

  7. The mechanism of color change in the neon tetra fish: a light-induced tunable photonic crystal array.

    PubMed

    Gur, Dvir; Palmer, Benjamin A; Leshem, Ben; Oron, Dan; Fratzl, Peter; Weiner, Steve; Addadi, Lia

    2015-10-12

    The fresh water fish neon tetra has the ability to change the structural color of its lateral stripe in response to a change in the light conditions, from blue-green in the light-adapted state to indigo in the dark-adapted state. The colors are produced by constructive interference of light reflected from stacks of intracellular guanine crystals, forming tunable photonic crystal arrays. We have used micro X-ray diffraction to track in time distinct diffraction spots corresponding to individual crystal arrays within a single cell during the color change. We demonstrate that reversible variations in crystal tilt within individual arrays are responsible for the light-induced color variations. These results settle a long-standing debate between the two proposed models, the "Venetian blinds" model and the "accordion" model. The insight gained from this biogenic light-induced photonic tunable system may provide inspiration for the design of artificial optical tunable systems.

  8. Complexes of tetra-tert-butyl-tetraazaporphine with Al(III) and Zr(IV) cations as fluoride selective ionophores.

    PubMed

    Górski, Lukasz; Mroczkiewicz, Monika; Pietrzak, Mariusz; Malinowska, Elzbieta

    2009-02-01

    In this work, complexes of Zr(IV) and Al(III) cations with 2,7,12,17-tetra-tert-butyl-5,10,15,20-tetraazaporphine (TAP) were tested as ionophores in plasticized PVC membranes of ion-selective electrodes. It was found that both tested ionophores show enhanced affinity towards fluoride anion. High fluoride selectivity was observed in the presence of anionic or cationic additives in the membrane, which indicates that proposed compounds work according to charged or neutral carrier mechanism, depending on membrane composition and pretreatment. tert-Butyl substituents, present in the structure of tested compounds, were supposed to prevent formation of ionophore dimers within the membrane phase. This process was found to be responsible for some unfavorable potentiometric properties of electrodes based on complexes of Zr(IV) and Al(III) cations with porphyrins (compounds closely related to tetra-tert-butyl-5,10,15,20-tetraazaporphine). As it was shown using spectrophotometrical measurements, Al(III)-TAP was not susceptible to dimerization, while dimer formation was observed for Zr(IV)-TAP. In full agreement with these observations, electrodes with membranes containing Al(III)-TAP responded in near-Nernstian and fast manner towards fluoride anion, while the employment of Zr(IV)-TAP as ionophore resulted in super-Nernstian and sluggish response. Plasticized PVC membranes doped with Al(III)-TAP and 20mol% of lipophilic anionic additives shown remarkable F(-) selectivity, with selectivity coefficients, logK(F-pot.).(Y-), as follows: -4.4 (Y(-)Br(-)), -4.3 (Cl(-)), -4.2 (NO(3)(-)), -3.6 (SCN(-)), -2.9 (ClO(4)(-)). PMID:19166721

  9. Tetra­aqua­bis­(piperazin-1-ium)cobalt(II) bis­(sulfate) dihydrate

    PubMed Central

    Sahbani, Thameur; Smirani Sta, Wajda; Rzaigui, Mohamed

    2013-01-01

    In the centrosymmetric title compound, [Co(C4H11N2)2(H2O)4](SO4)2·2H2O, the CoII atom is coordinated in a distorted octa­hedral geometry by four water O atoms and two piperazinium N atoms. These four water O atoms define an equatorial plane with a maximum deviation of 0.0384 (1) Å while the two piperazinium N atoms complete the octa­hedron in the axial positions. Neighboring complex mol­ecules and sulfate anions are connected through an extensive network of N—H⋯O and O—H⋯O hydrogen bonds, which link the different chemical species into layers in the ab plane. Additional Owater—H⋯O hydrogen bonds involving the non-coordinating water mol­ecules and C—H⋯O inter­actions connect these layers into a three-dimensional supra­molecular structure. PMID:24454163

  10. Synthesis, antimicrobial activity, structural and spectral characterization and DFT calculations of Co(II), Ni(II), Cu(II) and Pd(II) complexes of 4-amino-5-pyrimidinecarbonitrile.

    PubMed

    Mohamed, Tarek A; Shaaban, Ibrahim A; Farag, Rabei S; Zoghaib, Wajdi M; Afifi, Mahmoud S

    2015-01-25

    Co(II), Ni(II), Cu(II) and Pd(II) complexes of 4-amino-5-pyrimidinecarbonitrile (APC) have been synthesized and characterized using elemental analysis, magnetic susceptibility, mass spectrometry, infrared (4000-200 cm(-1)), UV-Visible (200-1100 nm), (1)H NMR and ESR spectroscopy as well as TGA analysis. The molar conductance measurements in DMSO imply non-electrolytic complexes, formulated as [M(APC)2Cl2] where M=Co(II), Ni(II), Cu(II) and Pd(II). The infrared spectra of Co(II), Ni(II) and Cu(II) complexes indicate a bidentate type of bonding for APC through the exocyclic amino and adjacent pyrimidine nitrogen as donors whereas APC coordinated to Pd(II) ion as a monodentated ligand via a pyrimidine nitrogen donor. The magnetic measurements and the electronic absorption spectra support distorted octahedral geometries for Co(II), Ni(II) and Cu(II) complexes however a square planar complex was favored for the Pd(II) complex (C2h skeleton symmetry). In addition, we carried out B3LYP and ω-B97XD geometry optimization at 6-31G(d) basis set except for Pd(II) where we implemented LanL2DZ/6-31G(d) combined basis set. The computational results favor all trans geometrical isomers where amino N, pyrimidine N and Cl are trans to each other (structure 1). Finally, APC and its divalent metal ion complexes were screened for their antibacterial activity, and the synthesized complexes were found to be more potent antimicrobial agents than APC against one or more microbial species. PMID:25105264

  11. Synthesis, antimicrobial activity, structural and spectral characterization and DFT calculations of Co(II), Ni(II), Cu(II) and Pd(II) complexes of 4-amino-5-pyrimidinecarbonitrile.

    PubMed

    Mohamed, Tarek A; Shaaban, Ibrahim A; Farag, Rabei S; Zoghaib, Wajdi M; Afifi, Mahmoud S

    2015-01-25

    Co(II), Ni(II), Cu(II) and Pd(II) complexes of 4-amino-5-pyrimidinecarbonitrile (APC) have been synthesized and characterized using elemental analysis, magnetic susceptibility, mass spectrometry, infrared (4000-200 cm(-1)), UV-Visible (200-1100 nm), (1)H NMR and ESR spectroscopy as well as TGA analysis. The molar conductance measurements in DMSO imply non-electrolytic complexes, formulated as [M(APC)2Cl2] where M=Co(II), Ni(II), Cu(II) and Pd(II). The infrared spectra of Co(II), Ni(II) and Cu(II) complexes indicate a bidentate type of bonding for APC through the exocyclic amino and adjacent pyrimidine nitrogen as donors whereas APC coordinated to Pd(II) ion as a monodentated ligand via a pyrimidine nitrogen donor. The magnetic measurements and the electronic absorption spectra support distorted octahedral geometries for Co(II), Ni(II) and Cu(II) complexes however a square planar complex was favored for the Pd(II) complex (C2h skeleton symmetry). In addition, we carried out B3LYP and ω-B97XD geometry optimization at 6-31G(d) basis set except for Pd(II) where we implemented LanL2DZ/6-31G(d) combined basis set. The computational results favor all trans geometrical isomers where amino N, pyrimidine N and Cl are trans to each other (structure 1). Finally, APC and its divalent metal ion complexes were screened for their antibacterial activity, and the synthesized complexes were found to be more potent antimicrobial agents than APC against one or more microbial species.

  12. Synthesis, characterization, DFT and biological studies of (Z)-N‧-(2-oxoindolin-3-ylidene)picolinohydrazide and its Co(II), Ni(II) and Cu(II) complexes

    NASA Astrophysics Data System (ADS)

    Rakha, T. H.; El-Gammal, O. A.; Metwally, H. M.; Abu El-Reash, G. M.

    2014-03-01

    The picolinohydrazide derivative: (Z)-N‧-(2-oxoindolin-3-ylidene)picolinohydrazide (H2IPH) and its Co(II), Ni(II) and Cu(II) complexes have been synthesized and investigated by using the modern spectroscopic and physicochemical techniques viz. IR, 1H NMR, UV-Vis spectrometric methods and magnetic moment measurements. The investigation study revealed that the ligand acts as monobasic tri- and tetradentate in Co(II) and Ni(II) complex, respectively and as neutral tridentate in Cu(II) complex. On the basis of magnetic moment and spectral studies, a six coordinated octahedral geometry is assigned for all complexes. The molecular modeling are drawn and showed the bond length, bond angle, chemical reactivity, energy components (kcal/mol) and binding energy (kcal/mol) for all the title compounds and also NLO for the ligand is shown. The energy gap between the HOMO and LUMO for Ni(II) complex is (-7 eV) which indicates that these compound is a promising structure for photovoltaic devices such as solar cells. A comparison of the experimental and theoretical spectra can be very useful in making correct assignments and understanding the basic chemical shift. The thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. The in vitro antibacterial studies of these complexes screened against pathogenic bacteria proved them as growth inhibiting agents. Antitumor activity, carried out in vitro on human mammary gland (breast) MCF7, have shown that the Co(II) complex exhibited potent activity followed by the ligand, Cu(II) and Ni(II) complexes.

  13. Crystal structure of (2E,4E)-5-[bis-(2-hy-droxy-eth-yl)amino]-1-(4-chloro-phen-yl)-5-phenyl-penta-2,4-dien-1-one.

    PubMed

    Golovanov, Alexander A; Vologzhanina, Anna V; Odin, Ivan S; Tret'yakova, Tat'yana P; Naumov, Sergey V

    2015-11-01

    In the title compound, C21H22ClNO3, the penta-diene unit is nearly planar [maximum deviation = 0.023 (1) Å], but the carbonyl O atom deviates significantly [by 0.304 (1) Å] from its mean plane, which is twisted with respect to the phenyl and chloro-benzene rings by 71.34 (13) and 46.40 (13)°, respectively. In the crystal, inversion-related molecules are linked by two pairs of O-H⋯O hydrogen bonds, forming chains propagating along [01-1], enclosing R (2) 2(16) and R (2) 2(22) ring motifs. The chains are linked via C-H⋯O hydrogen bonds and C-H⋯π inter-actions into a three-dimensional supra-molecular architecture. PMID:26594571

  14. Ethyl 2-(3-phenyl­thio­ureido)-5,6-di­hydro-4H-cyclo­penta­[b]thio­phene-3-carboxyl­ate

    PubMed Central

    de Oliveira, Jaismary G. B.; Mendonça Junior, Francisco J. B.; de Lima, Maria do Carmo A.; de Simone, Carlos A.; Ellena, Javier A.

    2012-01-01

    In the title compound, C17H18N2O2S2, the angle between the mean plane defined by the atoms of the 5,6-dihydro-4H-cyclo­penta­[b]thio­phene moiety (r.m.s. deviation = 0.19 Å) and the phenyl ring is 72.8°(2). The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O inter­action, which generates an S(6) ring motif. In the crystal, pairs of N—H⋯S hydrogen bonds link the mol­ecules to form inversion dimers with an R 2 2(8) ring motif. PMID:22904826

  15. Crystal structure of aqua[N-(2-oxidobenzyl-κO)-l-leucinato-κ2 N,O](1,10-phenanthroline-κ2 N,N′)­nickel(II) penta­hydrate

    PubMed Central

    Faizi, Md. Serajul Haque; Sharkina, Natalia O.

    2015-01-01

    In the title compound, [Ni(C13H17NO3)(C12H8N2)(H2O)]·5H2O, the NiII atom is in a distorted octa­hedral coordination environment provided by the two N atoms of one bidentate phenanthroline ligand and two O atoms and one N atom from a tridentate 2-[(2-hy­droxy­benz­yl)amino]-4-methyl­penta­noic acid (HAMA) ligand and one water mol­ecule. The complex was prepared by the reaction of nickel(II) nitrate with HAMA in the presence of 1,10-phenanthroline in a 1:1:1 ratio. In the crystal, the complex mol­ecules and solvate water mol­ecules are associated via O—H⋯O hydrogen bonds into a three-dimensional network. PMID:25878817

  16. Poly[[(methanol)(μ4-2,4,5,6-tetra­fluoro­benzene-1,3-dicarboxyl­ato)copper(II)] methanol monosolvate

    PubMed Central

    Yan, Dan; Duan, Qian

    2012-01-01

    In the title compound, {[Cu(C8F4O4)(CH3OH)]·CH3OH}n, two CuII atoms are bridged by four carboxyl­ate groups, forming the well known paddle-wheel secondary building unit (SBU) with axial methanol ligands. In each ligand, the dihedral angles between the benzene ring and the two carboxyl­ate groups are 80.43 (17) and 62.5 (4)°. Within each SBU, the four carboxyl­ate groups come from four symmetry-equivalent tetra­fluoro­isophthalate ligands. Each tetra­fluoro­isophthalate group connects two SBUs, forming a layered structure . In the crystal, O—H⋯O hydrogen bonds involving the free and ligated methanol mol­ecules link the mol­ecules into a three-dimensional supra­molecular network. PMID:22719324

  17. 4-{5-[(2-Bromo­benz­yl)sulfan­yl]-1H-tetra­zol-1-yl}benzoic acid

    PubMed Central

    Mafud, Ana C.; Mascarenhas, Yvonne P.; Nascimento, Alessandro S.

    2013-01-01

    In the title compound, C15H11BrN4O2S, the tetra­zole ring makes dihedral angles of 45.97 (10) and 75.41 (1)°, respectively, with the benzoyl and bromo­benzene rings while the dihedral angle between the benzene rings is 73.77 (1)°. In the crystal, mol­ecules are linked through O—H⋯ N and C—H⋯ O hydrogen bonds, giving infinite chains in both the [110] and [1-10] directions. These chains are further connected by C—Br⋯π and C—O⋯π inter­actions and also by π–π stacking between tetra­zole rings [centroid–centroid distance = 3.312 (1) Å], generating a three-dimensional network. PMID:24046647

  18. Design and performance of a ZnSe tetra-prism for homogeneous substrate heating using a CO2 laser for pulsed laser deposition experiments.

    PubMed

    May-Smith, T C; Muir, A C; Darby, M S B; Eason, R W

    2008-04-10

    We report on the design and performance of a ZnSe tetra-prism for homogeneous substrate heating using a continuous wave CO(2) laser beam in pulsed laser deposition experiments. We discuss here three potential designs for homogenizing prisms and use ray-tracing modeling to compare their operation to an alternative square-tapered beam-pipe design. A square-pyramidal tetra-prism design was found to be optimal and was subjected to modeling and experimental testing to determine the influence of interference and diffraction effects on the homogeneity of the resultant intensity profile produced at the substrate surface. A heat diffusion model has been used to compare the temperature distributions produced when using various different source intensity profiles. The modeling work has revealed the importance of substrate thickness as a thermal diffuser in producing a resultant homogeneous substrate temperature distribution. PMID:18404174

  19. Computational quest for spherical C12B68 fullerenes with "magic" π-electrons and quasi-planar tetra-coordinated carbon.

    PubMed

    Li, Fengyu; Jiang, De-en; Chen, Zhongfang

    2014-02-01

    Inspired by the exciting properties of B80 clusters and the novel chemical bonding of planar tetra-coordinated carbon (ptC), we computationally investigated C12B68 clusters by substituting 12 boron atoms to 12 carbon in the B80 framework. Three types of C12B68 configurations, namely core-shell, boron-trapped and fullerene-like, were examined. The fullerene-like C12B68 clusters are featured with multiple quasi-planar tetra-coordinated carbon moieties; though with "magic" (72) number of electrons, they are not highly aromatic due to the limitations of Hirsch's rule for clusters with more than 50 π electrons. These C12B68 fullerenes are not global minima, but the appreciable HOMO-LUMO gaps, spherical aromaticity, and the thermal stability indicate their reasonable stabilities.

  20. Ethyl 6-methyl-2-oxo-4-[4-(1H-tetra­zol-5-yl)phen­yl]-1,2,3,4-tetra­hydro­pyrimidine-5-carboxyl­ate–di­methyl­formamide–water (2/1/1)

    PubMed Central

    Ouyang, Hua-Yong; Chang, Yi-Qi; Zhao, Lu

    2014-01-01

    The asymmetric unit of the title compound, 2C15H16N6O3·C3H7NO·H2O, contains two independent ethyl 6-methyl-2-oxo-4-[4-(1H-tetra­zol-5-yl)phen­yl]-1,2,3,4-tetra­hydro­pyrim­id­ine-5-carboxyl­ate mol­ecules, in which the dihedral angles between the tetra­zole and benzene rings are 20.54 (12) and 12.13 (12)°. An intra­molecular C—H⋯O hydrogen bond occurs in each mol­ecule. In the crystal, N—H⋯O, N—H⋯N, O—H⋯O and O—H⋯N hydrogen bonds, as well as weak C—H⋯O and C—H⋯N hydrogen bonds, link the mol­ecules into a three-dimensional supra­molecular architecture. π–π stacking is also observed between parallel tetra­zole rings of adjacent mol­ecules, the centroid–centroid distance being 3.482 (6) Å. PMID:24526960

  1. Crystal structure of hexa­kis­(dmpu)-di-μ2-hydroxido-dialuminium tetraiodide dmpu tetra­solvate [dmpu is 1,3-di­methyl­tetra­hydro­pyrimidin-2(1H)-one]: a centrosymmetric dinuclear aluminium complex containing AlO5 polyhedra

    PubMed Central

    Lundberg, Daniel; Lyczko, Krzysztof

    2015-01-01

    The structure of the title compound, [Al2(OH)2(C6H12N2O)6]I4·4C6H12N2O (systematic name: di-μ2-hydroxido-bis­{tris­[1,3-di­methyl­tetra­hydro­pyrimidin-2(1H)-one-κO]aluminium} tetra­iodide 1,3-di­methyl­tetra­hydro­pyrimidin-2(1H)-one tetra­solvate), is composed of two Al(C6H12N2O)3 moieties linked into a centrosymmetric dinuclear unit by a pair of bridging hydroxide ions. The aluminium cations show a distorted trigonal bipyramidal AlO5 coordination environment formed only by monodentate ligands. The Al—O bond lengths are in the range 1.789 (2)–1.859 (2) Å (mean bond length = 1.818 Å). The non-coordinating iodide anions compensate the charge of the complex cation. The remaining solvent mol­ecules and the iodide counter-anions inter­act with the complex cation by weak non-classical C—H⋯I and C—H⋯O hydrogen bonds. PMID:26396749

  2. Coordination behavior of tetraaza [N4] ligand towards Co(II), Ni(II), Cu(II), Cu(I) and Pd(II) complexes: Synthesis, spectroscopic characterization and anticancer activity

    NASA Astrophysics Data System (ADS)

    El-Boraey, Hanaa A.

    2012-11-01

    Novel eight Co(II), Ni(II), Cu(II), Cu(I) and Pd(II) complexes with [N4] ligand (L) i.e. 2-amino-N-{2-[(2-aminobenzoyl)amino]ethyl}benzamide have been synthesized and structurally characterized by elemental analysis, spectral, thermal (TG/DTG), magnetic, and molar conductivity measurements. On the basis of IR, mass, electronic and EPR spectral studies an octahedral geometry has been proposed for Co(II), Ni(II) complexes and Cu(II) chloride complex, square-pyramidal for Cu(I) bromide complex. For Cu(II) nitrate complex (6), Pd(II) complex (8) square planar geometry was proposed. The EPR data of Cu(II) complexes in powdered form indicate dx2-y2 ground state of Cu(II) ion. The antitumor activity of the synthesized ligand and some selected metal complexes has been studied. The palladium(II) complex (8) was found to display cytotoxicity (IC50 = 25.6 and 41 μM) against human breast cancer cell line MCF-7 and human hepatocarcinoma HEPG2 cell line.

  3. New macrocyclic schiff base complexes incorporating a homopiperazine unit: Synthesis of some Co(II), Ni(II),Cu(II) and Zn(II) complexes and crystal structure and theoretical studies

    NASA Astrophysics Data System (ADS)

    Keypour, Hassan; Rezaeivala, Majid; Ramezani-Aktij, Ameneh; Bayat, Mehdi; Dilek, Nefise; Ünver, Hüseyin

    2016-07-01

    A new macrocyclic Schiff base ligand, L, was synthesized by condensation reaction of 1,4-bis(2-formylphenyl)homopiperazine and 1,4-diaminobutane in acetonitrile. The Schiff base ligand was characterized by using elemental analyses, FT-IR, 1H, 13C NMR and mass spectroscopic techniques. The metal (II) complexes [ML], were synthesized from the reaction of MCl2.nH2O (M: Co, Ni, Cu and Zn) with Schiff base ligand, L and characterized by elemental analyses and FT-IR. X-ray crystal structure of [CoLCl]+ distorted square pyramidal geometry with an N4Cl core, arising from coordination by the four donor nitrogen atoms from the macrocyclic framework and one Cl atom. It crystallizes triclinic space group, P-1 with a = 7.1777(1) Å, b = 11.0357 (2) Å, c = 15.1520(2) Å, V = 1183.14(3), Z = 2, Dc = 1.556 g cm-3, μ (MoKα) = 0.156 mm-1. Also, the bonding situation between the [MCl]+ and Ligand (L) fragments in [MLCl]ClO4 (M = Co(II), Ni(II), Cu(II), Zn(II)) complexes were carried out by energy-decomposition analysis (EDA). The results showed that there is an increasing trend in the case of ΔEelstat of the complexes by changing the M from Co(II) to Zn(II).

  4. Synthesis, spectroscopic, antimicrobial and DNA cleavage studies of new Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) complexes with naphthofuran-2-carbohydrazide Schiff base

    NASA Astrophysics Data System (ADS)

    Halli, Madappa B.; Sumathi, R. B.

    2012-08-01

    A series of Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) complexes have been synthesized with newly synthesized Schiff base derived from naphthofuran-2-carbohydrazide and cinnamaldehyde. The elemental analyses of the complexes are confined to the stoichiometry of the type MLCl2 [M = Co(II) and Cu(II)], ML2Cl2 [M = Ni(II), Cd(II), Zn(II) and Hg(II)] respectively, where L is Schiff base ligand. Structures have been proposed from elemental analyses, IR, electronic, mass, 1H NMR, ESR spectral data, magnetic, and thermal studies. The measured low molar conductance values in DMF indicate that the complexes are non-electrolytes. Spectroscopic studies suggest coordination occurs through azomethine nitrogen and carbonyl oxygen of the ligand with the metal ions. The Schiff base and its complexes have been screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Salmonella typhi) and antifungal (Aspergillus niger, Aspergillus flavus, Cladosporium and Candida albicans) activities by minimum inhibitory concentration (MIC) method. The DNA cleavage studies by agarose gel electrophoresis method was studied for all the complexes.

  5. Synthesis, characterization and biological activity of some new VO(IV), Co(II), Ni(II), Cu(II) and Zn(II) complexes of chromone based NNO Schiff base derived from 2-aminothiazole

    NASA Astrophysics Data System (ADS)

    Kalanithi, M.; Kodimunthiri, D.; Rajarajan, M.; Tharmaraj, P.

    2011-11-01

    Coordination compounds of VO(IV), Co(II), Ni(II), Cu(II) and Zn(II) with the Schiff base obtained through the condensation of 2-aminothiazole with 3-formyl chromone were synthesized. The compounds were characterized by 1H, 13C NMR, UV-Vis, IR, Mass, EPR, molar conductance and magnetic susceptibility measurements. The Cu(II) complex possesses tetrahedrally distorted square planar geometry whereas Co(II), Ni(II), and Zn(II) show distorted tetrahedral geometry. The VO(IV) complex shows square pyramidal geometry. The cyclic voltammogram of Cu (II) complex showed a well defined redox couple Cu(II)/Cu(I) with quasireversible nature. The antimicrobial activity against the species Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Candida albigans and Aspergillus niger was screened and compared to the activity of the ligand. Emission spectrum was recorded for the ligand and the metal(II) complexes. The second harmonic generation (SHG) efficiency was measured and found to have one fourth of the activity of urea. The SEM image of the copper(II) complex implies that the size of the particles is 2 μm.

  6. Synthesis, spectral, antitumor, antioxidant and antimicrobial studies on Cu(II), Ni(II) and Co(II) complexes of 4-[(1H-Benzoimidazol-2-ylimino)-methyl]-benzene-1,3-diol

    NASA Astrophysics Data System (ADS)

    El-wakiel, Nadia; El-keiy, Mai; Gaber, Mohamed

    2015-08-01

    A new Schiff base of 2-aminobenzimidazole with 2,4-dihydroybezaldehyde (H3L), and its Cu(II), Ni(II) and Co(II) complexes have been synthesized and characterized by elemental analyses, molar conductance, thermal analysis (TGA), inductive coupled plasma (ICP), magnetic moment measurements, IR, EI-mass, UV-Vis. and ESR spectral studies. On the basis of spectral studies and analytical data, it is evident that the Schiff base acts as dibasic tridentate ligand coordinating via deprotonated OH, NH and azomethine nitrogen atom. The results showed that Co(II) and Ni(II) complexes have tetrahedral structure while Cu(II) complexes has octahedral geometry. The kinetic and thermodynamic parameters of the thermal decomposition stages have been evaluated. The studied complexes were tested for their in vitro antimicrobial activities against some bacterial strains. The anticancer activity of the ligand and its metal complexes is evaluated against human liver Carcinoma (HEPG2) cell. These compounds exhibited a moderate and weak activity against the tested HEPG2 cell lines with IC50 of 9.08, 18.2 and 19.7 μg/ml for ligand, Cu(II) and Ni(II) complexes, respectively. In vitro antioxidant activity of the newly synthesized compounds has also been evaluated.

  7. Synthesis, characterization and biological activity of some new VO(IV), Co(II), Ni(II), Cu(II) and Zn(II) complexes of chromone based NNO Schiff base derived from 2-aminothiazole.

    PubMed

    Kalanithi, M; Kodimunthiri, D; Rajarajan, M; Tharmaraj, P

    2011-11-01

    Coordination compounds of VO(IV), Co(II), Ni(II), Cu(II) and Zn(II) with the Schiff base obtained through the condensation of 2-aminothiazole with 3-formyl chromone were synthesized. The compounds were characterized by (1)H, (13)C NMR, UV-Vis, IR, Mass, EPR, molar conductance and magnetic susceptibility measurements. The Cu(II) complex possesses tetrahedrally distorted square planar geometry whereas Co(II), Ni(II), and Zn(II) show distorted tetrahedral geometry. The VO(IV) complex shows square pyramidal geometry. The cyclic voltammogram of Cu (II) complex showed a well defined redox couple Cu(II)/Cu(I) with quasireversible nature. The antimicrobial activity against the species Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Candida albigans and Aspergillus niger was screened and compared to the activity of the ligand. Emission spectrum was recorded for the ligand and the metal(II) complexes. The second harmonic generation (SHG) efficiency was measured and found to have one fourth of the activity of urea. The SEM image of the copper(II) complex implies that the size of the particles is 2 μm.

  8. Tetra­kis(triphenyl­phosphane-κP)silver(I) trifluoro­methane­sulfonate dichloro­methane monosolvate

    PubMed Central

    Jiang, Yu-Hang; Cui, Li-Na; Huang, Xu; Jin, Qiong-Hua; Zhang, Cun-Lin

    2011-01-01

    In the title compound, [Ag(C18H15P)4]CF3O3S·CH2Cl2, the Ag atom is coordinated by four P atoms from four PPh3 ligands. The P—Ag—P angles are in the range 108.02 (6)–110.15 (6)°, which confirms the distorted tetra­hedral environment around the Ag atom. PMID:22219751

  9. 40 CFR 721.1800 - 3,3′,5,5′-Tetra-methyl-bi-phenyl-4,4′-diol.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 3,3â²,5,5â²-Tetra-methyl-bi-phenyl-4,4â²-diol. 721.1800 Section 721.1800 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1800...

  10. Synthesis, crystal structure and properties of a novel tetra-nuclear Cu complex of ANPyO

    SciTech Connect

    Liu Jinjian; Liu Zuliang; Cheng Jian

    2013-01-15

    A transition metal Cu complex with 2,6-diamino-3,5-dinitropyridine-N-oxide (ANPyO) ligand has been synthesized and its crystal structure has been analyzed by X-ray diffraction methods. The crystal belongs to Triclinic system with space group P-1. The cell parameters are a=8.6710(17) nm, b=11.226(2) nm, c=18.741(4) nm, {alpha}=98.26(3), {beta}=102.60(3), {gamma}=109.17(3), V=1635.1(6) nm{sup 3}, D{sub c}=1.957 g/cm{sup 3}, {mu}=2.663 mm{sup -1}, F(000)=968, Z=2, R{sub 1}=0.0764, WR{sub 2}=0.1608. The thermal decomposition process of the title complex was studied by means of the TG-DTG and DSC at a heating rate of 20 K/min. It consists of two slow endothermic peaks and one violent exothermic peak with 37.22% residues. The apparent activation energy and pre-exponential factor of the complex in thermal decomposition process were calculated by means of the Kissinger method and Ozawa-Doyle method. The thermal decomposition of AP was accelerated due to the catalyst of the complex, it suggests that the complex can provide theoretical support to further performance study as it is added to the propellant formulations to regulate the burning rate. - Graphical abstract: A novel tetra-nuclear Cu complex of ANPyO was synthesized and its molecular structure was measured. Highlights: Black-Right-Pointing-Pointer We have synthesized and characterized a new tetra-nuclear Cu complex. Black-Right-Pointing-Pointer We have measured its molecular structure and thermal decomposition. Black-Right-Pointing-Pointer A special coordination mode between ligand and central copper atoms has been obtained. Black-Right-Pointing-Pointer It provides theoretical support to further performance study as energetic catalyst.

  11. Different hydrogen-bonded structures in three 2-thienyl-substituted tetra­hydro-1,4-ep­oxy-1-benzazepines

    PubMed Central

    Blanco, Maria C.; Palma, Alirio; Bahsas, Ali; Cobo, Justo; Glidewell, Christopher

    2009-01-01

    The mol­ecules of (2RS,4SR)-2-exo-(5-bromo-2-thienyl)-7-chloro-2,3,4,5-tetra­hydro-1H-1,4-ep­oxy-1-benzazepine, C14H11BrClNOS, (I), are linked into cyclic centrosymmetric dimers by C—H⋯π(thienyl) hydrogen bonds. Each such dimer makes rather short Br⋯Br contacts with two other dimers. In (2RS,4SR)-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetra­hydro-1H-1,4-ep­oxy-1-benzazepine, C15H15NOS, (II), a com­bination of C—H⋯O and C—H⋯π(thienyl) hydrogen bonds links the mol­ecules into chains of rings. A more complex chain of rings is formed in (2RS,4SR)-7-chloro-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetra­hydro-1H-1,4-ep­oxy-1-benzazepine, C15H14ClNOS, (III), built from a combination of two independent C—H⋯O hydrogen bonds, one C—H⋯π(arene) hydrogen bond and one C—H⋯π(thienyl) hydro­gen bond. PMID:19726868

  12. Electropolymerizable peripherally tetra-{2-[3-(diethylamino)phenoxy]ethoxy} substituted as well as axially (4-phenylpiperazin-1-yl)propanoxy-disubstituted silicon phthalocyanines and their electrochemistry.

    PubMed

    Biyiklioglu, Zekeriya; Alp, Hakan

    2015-11-21

    A novel type of peripherally tetra-substituted as well as axially disubstituted silicon(iv) phthalocyanine containing electropolymerizable ligands was designed and synthesized for the first time. Axial bis-hydroxy silicon phthalocyanine 2 was prepared from 2(3),9(10),16(17),23(24)-tetrakis-{2-[3-(diethylamino)phenoxy]ethoxy}phthalocyanine 1 in dichloromethane by using 1.8-diazabicyclo[5.4.0]undec-7-ene (DBU) and trichlorosilane. Peripherally tetra and axially di-substituted silicon phthalocyanine 4 was synthesized from 2(3),9(10),16(17),23(24)-tetrakis-{2-[3-(diethylamino)phenoxy]ethoxy}silicon(iv)phthalocyanine dihydroxide 2 with 1-(3-chloropropyl)-4-phenylpiperazine 3 in toluene in the presence of NaH at 120 °C. These complexes were fully characterized by various spectroscopy techniques such as (1)H-NMR, (13)C-NMR, IR, UV-Vis, and MALDI-TOF spectroscopy and elemental analysis as well. Electropolymerization properties of silicon(IV) phthalocyanine complexes were investigated by cyclic and square wave voltammetry. Electrochemical studies reveal that silicon(IV) phthalocyanine complexes were electropolymerized on the working electrode during the anodic potential scan. This study is the first example of electropolymerization of both peripherally tetra and axially di-substituted silicon phthalocyanines on the same molecule.

  13. Crystal structure of non-centrosymmetric bis­(4-meth­oxy­benzyl­ammonium) tetra­chlorido­zincate

    PubMed Central

    Mahbouli Rhouma, Najla; Rayes, Ali; Mezzadri, Francesco; Calestani, Gianluca; Loukil, Mohamed

    2016-01-01

    The structure of the title non-centrosymmetric organic–inorganic hybrid salt, (C8H12NO)2[ZnCl4], consists of two 4-meth­oxy­benzyl­ammonium cations sandwiched between anionic layers, formed by isolated tetra­chlorido­zincate tetra­hedra. The double layers extend parallel to the ac plane. The crystal packing is assured by Coulombic inter­actions and by a complex N—H⋯Cl and C—H⋯Cl hydrogen-bonding system mostly involving the positively charged ammonium groups and the chloride ligands of the isolated tetra­hedral [ZnCl4]2− units. One of the methyl­ene­ammonium groups is disordered over two sets of sites in a 0.48 (2):0.52 (2) ratio. The crystal investigated was twinned by non-merohedry with a twin component ratio of 0.738 (2):0.262 (2). PMID:27555961

  14. Crystal structure of tetra-kis-(isonicotinamide-κN)bis-(thio-cyanato-κN)cobalt(II)-isonicotinamide-ethanol (1/2/1).

    PubMed

    Neumann, Tristan; Jess, Inke; Näther, Christian

    2016-08-01

    The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)4]·2C6H6N2O·C2H5OH, comprises one Co(II) cation, two thio-cyanate anions, four coordinating and two solvent isonicotinamide molecules and one ethanol solvent mol-ecule. The Co(II) cations are octa-hedrally coordinated by four N-coordinating isonicotinamide ligands and two terminally N-bonded thio-cyanate anions. These discrete complexes are linked by inter-molecular N-H⋯O and N-H⋯S hydrogen-bonding inter-actions into a three-dimensional network. The two isonicotinamide and the ethanol solvent mol-ecules are embedded in channels of this network and are linked through further N-H⋯O and N-H⋯N hydrogen bonds to the network. The ethanol solvent mol-ecule is disordered over two sets of sites (occupancy ratio 0.6:0.4). PMID:27536386

  15. Crystal structure of tetra­kis­(isonicotinamide-κN)bis­(thio­cyanato-κN)cobalt(II)–isonicotinamide–ethanol (1/2/1)

    PubMed Central

    Neumann, Tristan; Jess, Inke; Näther, Christian

    2016-01-01

    The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)4]·2C6H6N2O·C2H5OH, comprises one CoII cation, two thio­cyanate anions, four coordinating and two solvent isonicotinamide molecules and one ethanol solvent mol­ecule. The CoII cations are octa­hedrally coordinated by four N-coordinating isonicotinamide ligands and two terminally N-bonded thio­cyanate anions. These discrete complexes are linked by inter­molecular N—H⋯O and N—H⋯S hydrogen-bonding inter­actions into a three-dimensional network. The two isonicotinamide and the ethanol solvent mol­ecules are embedded in channels of this network and are linked through further N—H⋯O and N—H⋯N hydrogen bonds to the network. The ethanol solvent mol­ecule is disordered over two sets of sites (occupancy ratio 0.6:0.4). PMID:27536386

  16. Mn(III)(tetra-biphenyl-porphyrin)-TCNE single-chain magnet via suppression of the interchain interactions.

    PubMed

    Ishikawa, Ryuta; Katoh, Keiichi; Breedlove, Brian K; Yamashita, Masahiro

    2012-08-20

    A single-chain magnet (SCM) of [Mn(TBPP)(TCNE)]·4m-PhCl(2) (1), where TBPP(2-) = meso-tetra(4-biphenyl)porphyrinate; TCNE(•-) = tetracyanoethenide radical anion; m-PhCl(2) = meta-dichlorobenzene, was prepared via suppression of interchain interactions. 1 has a one-dimensional alternating Mn(III)(porphrin)-TCNE(•-)chain structure similar to those of a family of complexes reported by Miller and co-workers. From a comparison of the static magnetic properties of 1 with other Mn(III)(porphyrin)-TCNE(•-) chains, a magneto-structural correlation between the intrachain magnetic exchange and both the dihedral angle between the mean plane on [Mn(TBPP)(TCNE)] and Mn-N≡C was observed. The ac magnetic susceptibility data of 1 could be fit with the Arrhenius law, indicating that slow magnetic relaxation and ruling out three-dimensional long-range ordering and spin-glass-like behavior. The Cole-Cole plot for 1 was semicircular, verifying that it is an SCM. Therefore, 1 is an ideal single-chain magnet with significantly strong intrachain magnetic exchange interactions beyond the Ising limit.

  17. Influence of solvent polarity on the structure of drop-cast electroactive tetra(aniline)-surfactant thin films.

    PubMed

    Dane, Thomas G; Bartenstein, Julia E; Sironi, Beatrice; Mills, Benjamin M; Alexander Bell, O; Emyr Macdonald, J; Arnold, Thomas; Faul, Charl F J; Briscoe, Wuge H

    2016-09-21

    The influence of processing conditions on the thin film microstructure is a fundamental question that must be understood to improve the performance of solution-processed organic electronic materials. Using grazing-incidence X-ray diffraction, we have studied the structure of thin films of a tetra(aniline)-surfactant complex prepared by drop-casting from five solvents (hexane, chloroform, tetrahydrofuran, dichloromethane and ethanol), selected to cover a range of polarities. We found that the structure, level of order and degree of orientation relative to the substrate were extremely sensitive to the solvent used. We have attempted to correlate such solvent sensitivity with a variety of solvent physical parameters. Of particular significance is the observation of a sharp structural transition in the thin films cast from more polar solvents; such films presented significantly greater crystallinity as measured by the coherence length and paracrystalline disorder parameter. We attribute this higher structural order to enhanced dissociation of the acid surfactant in the more polar solvents, which in turn promotes complex formation. Furthermore, the more polar solvents provide more effective screening of (i) the attractive ionic interaction between oppositely charged molecules, providing greater opportunity for dynamic reorganisation of the supramolecular aggregates into more perfect structures; and (ii) the repulsive interaction between the positively charged blocks permitting a solvophobic-driven aggregation of the aromatic surfaces during solvent evaporation. PMID:27539382

  18. Self-assembly of PEGylated tetra-phenylalanine derivatives: structural insights from solution and solid state studies

    PubMed Central

    Diaferia, Carlo; Mercurio, Flavia Anna; Giannini, Cinzia; Sibillano, Teresa; Morelli, Giancarlo; Leone, Marilisa; Accardo, Antonella

    2016-01-01

    Water soluble fibers of PEGylated tetra-phenylalanine (F4), chemically modified at the N-terminus with the DOTA chelating agent, have been proposed as innovative contrast agent (CA) in Magnetic Resonance Imaging (MRI) upon complexation of the gadolinium ion. An in-depth structural characterization of PEGylated F4-fibers, in presence (DOTA-L6-F4) and in absence of DOTA (L6-F4), is reported in solution and at the solid state, by a multiplicity of techniques including CD, FTIR, NMR, DLS, WAXS and SAXS. This study aims to better understand how the aggregation process influences the performance of nanostructures as MRI CAs. Critical aggregation concentrations for L6-F4 (43 μM) and DOTA-L6-F4 (75 μM) indicate that self-aggregation process occurs in the same concentration range, independently of the presence of the CA. The driving force for the aggregation is the π-stacking between the side chains of the aromatic framework. CD, FTIR and WAXS measurements indicate an antiparallel β-sheet organization of the monomers in the resulting fibers. Moreover, WAXS and FTIR experiments point out that in solution the nanomaterials retain the same morphology and monomer organizations of the solid state, although the addition of the DOTA chelating agent affects the size and the degree of order of the fibers. PMID:27220817

  19. Citric acid and ethylene diamine tetra-acetic acid as effective washing agents to treat sewage sludge for agricultural reuse.

    PubMed

    Ren, Xianghao; Yan, Rui; Wang, Hong-Cheng; Kou, Ying-Ying; Chae, Kyu-Jung; Kim, In S; Park, Yong-Jin; Wang, Ai-Jie

    2015-12-01

    This paper presents the effects of different concentrations of citric acid (CA) and ethylene diamine tetra-acetic acid (EDTA) when used as additive reagents for the treatment of sewage sludge for agricultural use. Herein, both the retention of nutrients and removal of metals from the sewage sludge are examined. The average removal rate for the metals after treatment by CA decreased in the order Cu>Pb>Cd>Cr>Zn, while the rates after treatment by EDTA decreased in the order of Pb>Cu>Cr>Cd>Zn. After treatment with CA and EDTA, total nitrogen and total phosphorus concentrations in the sludge decreased, while the content of available nitrogen and Olsen-P increased. In addition, a multi-criteria analysis model-fuzzy analytic network process method (with 3 main factors and 12 assessment sub-factors) was adopted to evaluate the effectiveness of different treatment methods. The results showed that the optimal CA and EDTA concentrations for sewage sludge treatment were 0.60 and 0.125 mol/L, respectively.

  20. Embryonic and Morphological Development of Larvae and Juvenile of the Buenos Aires Tetra, Hyphessobrycon anisitsi (Pisces Characidae) Characidae Fishes.

    PubMed

    Park, Jae-Min; Han, Kyeong-Ho; Han, Ran

    2015-03-01

    We have launched an investigation for Embryonic Development, Larvae and Juvenile Morphology, of Buenos aires tetra in order to build basic data of Characidae and fish seeding production. We brought 50 couples of Characidae from Bizidduck aquarium in Yeosu-si, Jeollanamdo, from Korea on March of 2015. We put them in the tetragonal glass aquarium (50×50×30 cm). Breeding water temperature was 27.5~28.5°C (mean 28.0±0.05°C) and being maintained. The shape of fertilized egg was round shape, and it was adhesive demersal egg. The egg size was 0.63~0.91 mm (mean 0.74±0.07 mm, n=20). After getting fertilized egg, the developmental stage was gastrula stage, and embryo covered almost two-thirds of Yolk. Incubation was happened after 16 hours 13 minutes from gastrula stage, and the tail of juvenile came out first with tearing egg capsule. Immediately after the incubation, prelarvae had 3.78~3.88 mm length (mean 3.84±0.04 mm, n=5), and it had no mouth and anus yet. 34 days after hatching from the incubation, juvenile had 8.63~13.1 mm (mean 10.9±1.66 mm), and it had similar silver-colored body shape with its mother.

  1. Photodynamic Therapy of the Murine LM3 Tumor Using Meso-Tetra (4-N,N,N-Trimethylanilinium) Porphine

    PubMed Central

    Colombo, L. L.; Juarranz, A.; Cañete, M.; Villanueva, A.; Stockert, J. C.

    2007-01-01

    Photodynamic therapy (PDT) of cancer is based on the cytotoxicity induced by a photosensitizer in the presence of oxygen and visible light, resulting in cell death and tumor regression. This work describes the response of the murine LM3 tumor to PDT using meso-tetra (4-N,N,N-trimethylanilinium) porphine (TMAP). BALB/c mice with intradermal LM3 tumors were subjected to intravenous injection of TMAP (4 mg/kg) followed 24 h later by blue-red light irradiation (λmax: 419, 457, 650 nm) for 60 min (total dose: 290 J/cm2) on depilated and glycerol-covered skin over the tumor of anesthetized animals. Control (drug alone, light alone) and PDT treatments (drug + light) were performed once and repeated 48 h later. No significant differences were found between untreated tumors and tumors only treated with TMAP or light. PDT-treated tumors showed almost total but transitory tumor regression (from 3 mm to less than 1 mm) in 8/9 animals, whereas no regression was found in 1/9. PDT response was heterogeneous and each tumor showed different regression and growth delay. The survival of PDT-treated animals was significantly higher than that of TMAP and light controls, showing a lower number of lung metastasis but increased tumor-draining lymph node metastasis. Repeated treatment and reduction of tissue light scattering by glycerol could be useful approaches in studies on PDT of cancer. PMID:23675051

  2. Synthesis, dark toxicity and induction of in vitro DNA photodamage by a tetra(4-nido-carboranylphenyl)porphyrin.

    PubMed

    Vicente, M G H; Nurco, D J; Shetty, S J; Osterloh, J; Ventre, E; Hegde, V; Deutsch, W A

    2002-11-01

    The total synthesis of tetra(4-carboranylphenyl)porphyrins 4 and 6 and their zinc(II) complexes 5 and 7 are described. These compounds were characterized by analytical and spectroscopic methods and, in the case of 5, by X-ray crystallography. The water-soluble nido-carboranylporphyrins 6 and 7 were found to have low dark toxicity towards V79 hamster lung fibroblast cells, using a clonogenic assay (50% colony survival, CS(50)>300 microM). Upon light activation nido-carboranylporphyrin 6 effectively induced DNA damage in vitro. Two different methods were used to assess the extent of DNA damage: the super-coiled to nicked DNA and the alkaline Comet assay using human leukemia K562 cells. Significant PDT-induced DNA damage was observed for porphyrin 6 using both assays, compared to light-only and porphyrin-only experiments. It is concluded that this type of nido-carboranylporphyrin is a promising sensitizer for both the boron neutron capture therapy and the photodynamic therapy of tumors.

  3. Separation properties of aluminium-plastic laminates in post-consumer Tetra Pak with mixed organic solvent.

    PubMed

    Zhang, S F; Zhang, L L; Luo, K; Sun, Z X; Mei, X X

    2014-04-01

    The separation properties of the aluminium-plastic laminates in postconsumer Tetra Pak structure were studied in this present work. The organic solvent blend of benzene-ethyl alcohol-water was used as the separation reagent. Then triangle coordinate figure analysis was taken to optimize the volume proportion of various components in the separating agent and separation process. And the separation temperature of aluminium-plastic laminates was determined by the separation time, efficiency, and total mass loss of products. The results show that cost-efficient separations perform best with low usage of solvents at certain temperatures, for certain times, and within a certain range of volume proportions of the three components in the solvent agent. It is also found that similar solubility parameters of solvents and polyethylene adhesives (range 26.06-34.85) are a key factor for the separation of the aluminium-plastic laminates. Such multisolvent processes based on the combined-system concept will be vital to applications in the recycling industry.

  4. Efficient convergent synthesis of bi-, tri-, and tetra-antennary complex type N-glycans and their HIV-1 antigenicity.

    PubMed

    Shivatare, Sachin S; Chang, Shih-Huang; Tsai, Tsung-I; Ren, Chien-Tai; Chuang, Hong-Yang; Hsu, Li; Lin, Chih-Wei; Li, Shiou-Ting; Wu, Chung-Yi; Wong, Chi-Huey

    2013-10-16

    The structural diversity of glycoproteins often comes from post-translational glycosylation with heterogeneous N-glycans. Understanding the complexity of glycans related to various biochemical processes demands a well-defined synthetic sugar library. We report herein a unified convergent strategy for the rapid production of bi-, tri-, and tetra-antennary complex type N-glycans with and without terminal N-acetylneuraminic acid residues connected via the α-2,6 or α-2,3 linkages. Moreover, using sialyltransferases to install sialic acid can minimize synthetic steps through the use of shared intermediates to simplify the complicated procedures associated with conventional sialic acid chemistry. Furthermore, these synthetic complex oligosaccharides were compiled to create a glycan array for the profiling of HIV-1 broadly neutralizing antibodies PG9 and PG16 that were isolated from HIV infected donors. From the study of antibody PG16, we identified potential natural and unnatural glycan ligands, which may facilitate the design of carbohydrate-based immunogens and hasten the HIV vaccine development.

  5. Embryonic and Morphological Development of Larvae and Juvenile of the Buenos Aires Tetra, Hyphessobrycon anisitsi (Pisces Characidae) Characidae Fishes

    PubMed Central

    Park, Jae-Min; Han, Kyeong-Ho; Han, Ran

    2015-01-01

    We have launched an investigation for Embryonic Development, Larvae and Juvenile Morphology, of Buenos aires tetra in order to build basic data of Characidae and fish seeding production. We brought 50 couples of Characidae from Bizidduck aquarium in Yeosu-si, Jeollanamdo, from Korea on March of 2015. We put them in the tetragonal glass aquarium (50×50×30 cm). Breeding water temperature was 27.5~28.5°C (mean 28.0±0.05°C) and being maintained. The shape of fertilized egg was round shape, and it was adhesive demersal egg. The egg size was 0.63~0.91 mm (mean 0.74±0.07 mm, n=20). After getting fertilized egg, the developmental stage was gastrula stage, and embryo covered almost two-thirds of Yolk. Incubation was happened after 16 hours 13 minutes from gastrula stage, and the tail of juvenile came out first with tearing egg capsule. Immediately after the incubation, prelarvae had 3.78~3.88 mm length (mean 3.84±0.04 mm, n=5), and it had no mouth and anus yet. 34 days after hatching from the incubation, juvenile had 8.63~13.1 mm (mean 10.9±1.66 mm), and it had similar silver-colored body shape with its mother. PMID:25949207

  6. Citric acid and ethylene diamine tetra-acetic acid as effective washing agents to treat sewage sludge for agricultural reuse.

    PubMed

    Ren, Xianghao; Yan, Rui; Wang, Hong-Cheng; Kou, Ying-Ying; Chae, Kyu-Jung; Kim, In S; Park, Yong-Jin; Wang, Ai-Jie

    2015-12-01

    This paper presents the effects of different concentrations of citric acid (CA) and ethylene diamine tetra-acetic acid (EDTA) when used as additive reagents for the treatment of sewage sludge for agricultural use. Herein, both the retention of nutrients and removal of metals from the sewage sludge are examined. The average removal rate for the metals after treatment by CA decreased in the order Cu>Pb>Cd>Cr>Zn, while the rates after treatment by EDTA decreased in the order of Pb>Cu>Cr>Cd>Zn. After treatment with CA and EDTA, total nitrogen and total phosphorus concentrations in the sludge decreased, while the content of available nitrogen and Olsen-P increased. In addition, a multi-criteria analysis model-fuzzy analytic network process method (with 3 main factors and 12 assessment sub-factors) was adopted to evaluate the effectiveness of different treatment methods. The results showed that the optimal CA and EDTA concentrations for sewage sludge treatment were 0.60 and 0.125 mol/L, respectively. PMID:26235448

  7. Influence of solvent polarity on the structure of drop-cast electroactive tetra(aniline)-surfactant thin films.

    PubMed

    Dane, Thomas G; Bartenstein, Julia E; Sironi, Beatrice; Mills, Benjamin M; Alexander Bell, O; Emyr Macdonald, J; Arnold, Thomas; Faul, Charl F J; Briscoe, Wuge H

    2016-09-21

    The influence of processing conditions on the thin film microstructure is a fundamental question that must be understood to improve the performance of solution-processed organic electronic materials. Using grazing-incidence X-ray diffraction, we have studied the structure of thin films of a tetra(aniline)-surfactant complex prepared by drop-casting from five solvents (hexane, chloroform, tetrahydrofuran, dichloromethane and ethanol), selected to cover a range of polarities. We found that the structure, level of order and degree of orientation relative to the substrate were extremely sensitive to the solvent used. We have attempted to correlate such solvent sensitivity with a variety of solvent physical parameters. Of particular significance is the observation of a sharp structural transition in the thin films cast from more polar solvents; such films presented significantly greater crystallinity as measured by the coherence length and paracrystalline disorder parameter. We attribute this higher structural order to enhanced dissociation of the acid surfactant in the more polar solvents, which in turn promotes complex formation. Furthermore, the more polar solvents provide more effective screening of (i) the attractive ionic interaction between oppositely charged molecules, providing greater opportunity for dynamic reorganisation of the supramolecular aggregates into more perfect structures; and (ii) the repulsive interaction between the positively charged blocks permitting a solvophobic-driven aggregation of the aromatic surfaces during solvent evaporation.

  8. Seventy-five-million-year-old tropical tetra-like fish from Canada tracks Cretaceous global warming.

    PubMed

    Newbrey, M G; Murray, A M; Wilson, M V H; Brinkman, D B; Neuman, A G

    2009-11-01

    Newly discovered fossil fish material from the Cretaceous Dinosaur Park Formation of Alberta, Canada, documents the presence of a tropical fish in this northern area about 75 million years ago (Ma). The living relatives of this fossil fish, members of the Characiformes including the piranha and neon tetras, are restricted to tropical and subtropical regions, being limited in their distribution by colder temperatures. Although characiform fossils are known from Cretaceous through to Cenozoic deposits, none has been reported previously from North America. The modern distribution of characiforms in Mexico and southern Texas in the southernmost United States is believed to have been the result of a relatively recent colonization less than 12 Ma. The new Canadian fossils document the presence of these fish in North America in the Late Cretaceous, a time of significantly warmer global temperatures than now. Global cooling after this time apparently extirpated them from the northern areas and these fishes only survived in more southern climes. The lack of early Cenozoic characiform fossils in North America suggests that marine barriers prevented recolonization during warmer times, unlike in Europe where Eocene characiform fossils occur during times of global warmth.

  9. Seventy-five-million-year-old tropical tetra-like fish from Canada tracks Cretaceous global warming

    PubMed Central

    Newbrey, M. G.; Murray, A. M.; Wilson, M. V. H.; Brinkman, D. B.; Neuman, A. G.

    2009-01-01

    Newly discovered fossil fish material from the Cretaceous Dinosaur Park Formation of Alberta, Canada, documents the presence of a tropical fish in this northern area about 75 million years ago (Ma). The living relatives of this fossil fish, members of the Characiformes including the piranha and neon tetras, are restricted to tropical and subtropical regions, being limited in their distribution by colder temperatures. Although characiform fossils are known from Cretaceous through to Cenozoic deposits, none has been reported previously from North America. The modern distribution of characiforms in Mexico and southern Texas in the southernmost United States is believed to have been the result of a relatively recent colonization less than 12 Ma. The new Canadian fossils document the presence of these fish in North America in the Late Cretaceous, a time of significantly warmer global temperatures than now. Global cooling after this time apparently extirpated them from the northern areas and these fishes only survived in more southern climes. The lack of early Cenozoic characiform fossils in North America suggests that marine barriers prevented recolonization during warmer times, unlike in Europe where Eocene characiform fossils occur during times of global warmth. PMID:19675010

  10. Selective accumulation of meso-tetra(hydroxyphenyl)chlorin in steroid-synthesizing cells of the rat adrenal gland

    NASA Astrophysics Data System (ADS)

    Colombo-Benkmann, Mario; Muhm, Markus; Gahlen, Johannes; Vry, Magnus-Sebastian; Deubzer, Hedwig; Holloschi, Andreas; Haffner, Matthias; Heym, Christine; Senninger, Norbert

    1998-04-01

    Rat adrenal glands fluoresce intensely after systemic application of meso-tetra(hydroxyphenyl)chlorin (mTHPC). We investigated which parts of the adrenal gland accumulate mTHPC. Furthermore we examined the time course of adrenal mTHPC-accumulation. Ten male Wistar rats each were given 0.5 or 0.7 mg mTHPC kg-1 iv. Each two animals were perfused with normal saline and Zamboni fixative 6, 12, 24, 48 and 72 hours after photosensitization. Untreated animals served as controls. Fluorescence was quantified on 20 micrometer frozen sections with CCD-camera and appropriate software. Immunohistochemistry identified specific cell types with antibodies to steroid-synthesizing enzymes. The cortex exhibited an intense fluorescence, with weaker fluorescence of corticocytes in the zona glomerulosa compared to the other zones. Besides intensely fluorescing singly lying scattered cells, the medulla showed a faint mTHPC-induced fluorescence. Immunohistochemistry revealed that intramedullary cells with intense fluorescence were corticocytes, showing a positive reaction to the 21-(beta) -hydroxylase antibody. Peak accumulation of mTHPC was always observed after 24 hours. Our results indicate for the first time that only steroid synthesizing cells of the adrenal gland exhibit an intense photosensitizer-induced fluorescence. Thus mTHPC-application is an uncomplicated method to identify steroid-synthesizing cells, possibly also in other organs.

  11. Structural differences in two polymorphs of tetra-kis-(dimethylamino)-ethylene-C{sub 60}: An x-ray diffraction study

    SciTech Connect

    Fujiwara, Motoyasu; Kambe, Takashi; Oshima, Kokichi

    2005-05-01

    A type of low-temperature structure for ferromagnetic {alpha}-tetra-kis (dimethylamino)-ethylene (TDAE)-C{sub 60} is proposed on the basis of low-temperature x-ray analysis. We observed that intense superlattice reflections with odd indices successively appeared below T{sub s}=170 K. The space group symmetry of the low-temperature phase is determined to be P2{sub 1}/n. Two inequivalent C{sub 60} sites exist in the low-temperature phase, which are indispensable to the orbital ordering model of C{sub 60}. The contact configuration for the neighboring C{sub 60}s along the stacking c direction is uniquely determined. The double bond between the hexagons faces the neighboring pentagon. We found that the surrounding TDAE molecules shift along the c axis ({approx}0.07 A) and that these shifts correlate perfectly to the alignment of C{sub 60}. This result indicates that the steric effect between C{sub 60} and TDAE molecules plays an important role in the orientational ordering of C{sub 60}. On the other hand, in the {alpha}{sup '} phase, no structural phase transition was observed below 30 K. This indicates that all the C{sub 60}s are crystallographically equivalent. Structural differences separate the magnetic peculiarities of the two polymorphs in TDAE-C{sub 60}.

  12. Non-identity of human plasma lysozyme and 4-methylumbelliferyl-tetra-N-acetyl-beta-D-chitotetraoside hydrolase.

    PubMed

    Den Tandt, W R; Inaba, T; Verhamme, I; Overdyk, B; Brouwer, J; Prieur, D

    1988-01-01

    1. Using 4-methylumbelliferyl-tetra-N-acetyl-beta-D-chitotetraoside (MU-TACT) as substrate, it is possible to measure the activity of purified lysozyme and to demonstrate lysozyme activity in the urine of patients with acute monocytic leukemia, characterized by massive lysozymuria. 2. Notwithstanding this observation, we present evidence that in normal human plasma another acid endoglucosaminidase is hydrolyzing the substrate. 3. The following data support the hypothesis of the existence of a separate hydrolase: (a) Thermoinactivation is different for MU-TACT hydrolase and lysozyme. (b) In plasma and many other biological samples, the concentration of lysozyme is too low to be measured with the artificial substrate and there is no correlation between MU-TACT hydrolase and lysozyme. (c) Serum of lysozyme deficient rabbits has normal MU-TACT hydrolase activity. (d) On Sephadex G-200 and DEAE cellulose chromatography, lysozyme and MU-TACT hydrolase are eluted separately. (e) Immunoremoval of lysozyme from human plasma does not affect the activity towards MU-TACT. (f) The effect of N-acetylglucosamine and N-acetylmuramic acid on the activity of lysozyme and MU-TACT hydrolase is different. PMID:3181601

  13. Self-assembly of PEGylated tetra-phenylalanine derivatives: structural insights from solution and solid state studies.

    PubMed

    Diaferia, Carlo; Mercurio, Flavia Anna; Giannini, Cinzia; Sibillano, Teresa; Morelli, Giancarlo; Leone, Marilisa; Accardo, Antonella

    2016-01-01

    Water soluble fibers of PEGylated tetra-phenylalanine (F4), chemically modified at the N-terminus with the DOTA chelating agent, have been proposed as innovative contrast agent (CA) in Magnetic Resonance Imaging (MRI) upon complexation of the gadolinium ion. An in-depth structural characterization of PEGylated F4-fibers, in presence (DOTA-L6-F4) and in absence of DOTA (L6-F4), is reported in solution and at the solid state, by a multiplicity of techniques including CD, FTIR, NMR, DLS, WAXS and SAXS. This study aims to better understand how the aggregation process influences the performance of nanostructures as MRI CAs. Critical aggregation concentrations for L6-F4 (43 μM) and DOTA-L6-F4 (75 μM) indicate that self-aggregation process occurs in the same concentration range, independently of the presence of the CA. The driving force for the aggregation is the π-stacking between the side chains of the aromatic framework. CD, FTIR and WAXS measurements indicate an antiparallel β-sheet organization of the monomers in the resulting fibers. Moreover, WAXS and FTIR experiments point out that in solution the nanomaterials retain the same morphology and monomer organizations of the solid state, although the addition of the DOTA chelating agent affects the size and the degree of order of the fibers. PMID:27220817

  14. Gondola-shaped tetra-rhenium metallacycles modified evanescent wave infrared chemical sensors for selective determination of volatile organic compounds.

    PubMed

    Huang, Genin Gary; Lee, Chung-Jay; Tsai, Bo-Chan; Yang, Jyisy; Sathiyendiran, Malaichamy; Lu, Kuang-Lieh

    2011-07-15

    Water-stable and cavity-contained rhenium metallacycles were synthesized, and their ability to selectively interact with volatile organic compounds (VOCs) systematically studied using attenuated total reflection infrared (ATR-IR) spectroscopy. Integrating the unique properties of rhenium metallacycles into optical sensing technologies significantly improves selectivity in detecting aromatic compounds. To explore the interaction of rhenium metallacycles with VOCs, the surface of ATR sensing elements was modified with the synthesized rhenium metallacycles and used to detect VOCs. The results indicate that rhenium metallacycles have crown ether-like recognition sites, which can selectively interact with aromatic compounds, especially those bearing polar functional groups. The IR absorption bands of rhenium metallacycles shift significantly upon adsorption of aromatic VOCs, revealing a strong interaction between the tetra-rhenium metallacycles and guest aromatic compounds. Optimizing the thickness of the metallacycles coated on the surface of the sensing element led to rapid response in detection. The dynamic range of response was generally up to 30 mg/L with detection limits ca. 30 μg/L. Further studies of the effect of interferences indicate that recovery can be higher than 95% for most of the compounds tested. The results on the flow-cell device indicated that the performances were similar to a static detection system but the detection of VOCs can be largely simplified.

  15. In vitro cytotoxicity assessment of [5,10,15,20-tetra (4-sulfophenyl) porphyrin] on tumor and nontumor cell lines

    NASA Astrophysics Data System (ADS)

    Alexandrova, R.; Sabotinov, O.; Stoykova, Elena V.; Ion, Rodica-Mariana; Shurulinkov, Stanislav; Minchev, Georgi

    2004-06-01

    In this study we evaluate the cytotoxicity of 5,10,15,20- tetra (4-sulfophenyl) porphyrins on a tumor cell line LSCC-SF-Mc29, obtained from a transplantable chicken hepatoma induced by the myelocytomatosis virus Mc29, a timor line LSR-SF-SR, obtained from a transplantable sarcoma in rat induced by Rous sarcoma virus strain Schmidt-Ruppin and for normal mouse cell line (BALB/c-3T3-A31) and bovine kidney cell line (MDBK). The cells were exposed to irradiation from a pulsed CuBr vapor laser system at 510.6 nm and 578.2 nm at fluence rate 50 mW/cm2 and pulse frequency rate 20 kHz. The viability of cells was determined by the neutral red uptake cytotoxicity assay. The light dose-response curves and light exposures that ensure viability drop to 50 % were obtained for each cell line. The cytotoxic effect of TS4PP is most distinguished for LSCC-SF-Mc29. The bovine cell line is more vulnerable than the mouse line, especially at 510.6 nm. The 2-4 times higher viability of the normal cell lines in comparison with the tumor lines has been obtained.

  16. Supramolecular architectures in Co(II) and Cu(II) complexes with thiophene-2-carboxylate and 2-amino-4,6-dimethoxypyrimidine ligands.

    PubMed

    Karthikeyan, Ammasai; Thomas Muthiah, Packianathan; Perdih, Franc

    2016-05-01

    The coordination chemistry of mixed-ligand complexes continues to be an active area of research since these compounds have a wide range of applications. Many coordination polymers and metal-organic framworks are emerging as novel functional materials. Aminopyrimidine and its derivatives are flexible ligands with versatile binding and coordination modes which have been proven to be useful in the construction of organic-inorganic hybrid materials and coordination polymers. Thiophenecarboxylic acid, its derivatives and their complexes exhibit pharmacological properties. Cobalt(II) and copper(II) complexes of thiophenecarboxylate have many biological applications, for example, as antifungal and antitumor agents. Two new cobalt(II) and copper(II) complexes incorporating thiophene-2-carboxylate (2-TPC) and 2-amino-4,6-dimethoxypyrimidine (OMP) ligands have been synthesized and characterized by X-ray diffraction studies, namely (2-amino-4,6-dimethoxypyrimidine-κN)aquachlorido(thiophene-2-carboxylato-κO)cobalt(II) monohydrate, [Co(C5H3O2S)Cl(C6H9N3O2)(H2O)]·H2O, (I), and catena-poly[copper(II)-tetrakis(μ-thiophene-2-carboxylato-κ(2)O:O')-copper(II)-(μ-2-amino-4,6-dimethoxypyrimidine-κ(2)N(1):N(3))], [Cu2(C5H3O2S)4(C6H9N3O2)]n, (II). In (I), the Co(II) ion has a distorted tetrahedral coordination environment involving one O atom from a monodentate 2-TPC ligand, one N atom from an OMP ligand, one chloride ligand and one O atom of a water molecule. An additional water molecule is present in the asymmetric unit. The amino group of the coordinated OMP molecule and the coordinated carboxylate O atom of the 2-TPC ligand form an interligand N-H...O hydrogen bond, generating an S(6) ring motif. The pyrimidine molecules also form a base pair [R2(2)(8) motif] via a pair of N-H...N hydrogen bonds. These interactions, together with O-H...O and O-H...Cl hydrogen bonds and π-π stacking interactions, generate a three-dimensional supramolecular architecture. The one

  17. Spectroscopic and thermal degradation behavior of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes with thiopental sodium anesthesia drug

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.

    2013-04-01

    A new series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized with thiopental sodium anesthesia drug. The elemental analyses of the complexes are confined to stoichiometry of the formulas [M(TPL)3]ṡnH2O (M = Cr(III) or Fe(III); n = 6 or 5), [M(TPL)2(H2O)2]ṡnH2O (M = Mn(II), Co(II) or Ni(II); n = 0 or 4), and [M(TPL)2] (M = Cu(II) or Zn(II); n = 2 or 0) respectively, where TPL is thiopental chelating agent. Structures have been discussed and suggested upon elemental analyses, infrared, Raman, electronic, electron spin resonance, 1H NMR spectral data and magnetic studies. The X-ray powder diffraction (XRD) was performed of metal complexes. The XRD patterns indicate crystalline nature for the complexes. The measured low molar conductance values in dimethylsulfoxide indicate that the complexes are non-electrolyte nature. Spectroscopic discussion refer that coordination take place through three types: Cdbnd N (pyrimidine moiety) nitrogen and C2sbnd S (2-thiolate group) for Cr(III), Mn(II) and Fe(III), C6dbnd O (amido group) oxygen and C2sbnd S (2-thiolate group) for Co(II) and Ni(II), and Cu(II) and Zn(II) ions coordinated via Cdbnd N (pyrimidine moiety) nitrogen, C2dbnd S (2-thiolate group) and C6dbnd O (amido group) oxygen, respectively. The thermal behavior (TG/DTG/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz-Metzger and Coats-Redfern methods. The thiopental and its complexes have been screened for their antimicrobial (G+ and G-) bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa) and fungi (Aspergillus flavus and Candida albicans) activities by minimum inhibitory concentration (MIC) method.

  18. Crystal structure of cyclo-tris­(μ-3,4,5,6-tetra­fluoro-o-phenyl­ene-κ2 C 1:C 2)trimercury–tetra­cyano­ethyl­ene (1/1)

    PubMed Central

    Castañeda, Raúl; Timofeeva, Tatiana V.; Khrustalev, Victor N.

    2015-01-01

    The title compound, [Hg3(C6F4)3]·C6N4, contains one mol­ecule of tetra­cyano­ethyl­ene B per one mol­ecule of mercury macrocycle A, i.e., A•B, and crystallizes in the monoclinic space group C2/c. Macrocycle A and mol­ecule B both occupy special positions on a twofold rotation axis and the inversion centre, respectively. The supra­molecular unit [A•B] is built by the simultaneous coordination of one of the nitrile N atoms of B to the three mercury atoms of the macrocycle A. The Hg⋯N distances range from 2.990 (4) to 3.030 (4) Å and are very close to those observed in the related adducts of the macrocycle A with other nitrile derivatives. The mol­ecule of B is almost perpendicular to the mean plane of the macrocycle A at the dihedral angle of 88.20 (5)°. The donor–acceptor Hg⋯N inter­actions do not affect the C N bond lengths [1.136 (6) and 1.140 (6) Å]. The trans nitrile group of B coordinates to another macrocycle A, forming an infinite mixed-stack [A•B]∞ architecture toward [101]. The remaining N atoms of two nitrile groups of B are not engaged in any donor–acceptor inter­actions. In the crystal, the mixed stacks are held together by inter­molecular C—F⋯C N secondary inter­actions [2.846 (5)–2.925 (5) Å]. PMID:26594514

  19. Synthesis, spectroscopic characterization and biological activities of N4O2 Schiff base ligand and its metal complexes of Co(II), Ni(II), Cu(II) and Zn(II)

    NASA Astrophysics Data System (ADS)

    Al-Resayes, Saud I.; Shakir, Mohammad; Abbasi, Ambreen; Amin, Kr. Mohammad Yusuf; Lateef, Abdul

    The Schiff base ligand, bis(indoline-2-one)triethylenetetramine (L) obtained from condensation of triethylenetetramine and isatin was used to synthesize the complexes of type, [ML]Cl2 [M = Co(II), Ni(II), Cu(II) and Zn(II)]. L was characterized on the basis of the results of elemental analysis, FT-IR, 1H and 13C NMR, mass spectroscopic studies. The stoichiometry, bonding and stereochemistries of complexes were ascertained on the basis of results of elemental analysis, magnetic susceptibility values, molar conductance and various spectroscopic studies. EPR, UV-vis and magnetic moments revealed an octahedral geometry for complexes. L and its Cu(II) and Zn(II) complexes were screened for their antibacterial activity. Analgesic activity of Cu(II) and Zn(II) complexes was also tested in rats by tail flick method. Both complexes were found to possess good antibacterial and moderate analgesic activity.

  20. Adsorption of Co(II), Ni(II), Cu(II), and Zn(II) on hexagonal templated zirconia obtained thorough a sol-gel process: the effects of nanostructure on adsorption features.

    PubMed

    de Farias, Robson F; do Nascimento, Ana A S; Bezerra, Cícero W B

    2004-09-01

    Using zirconium tetrabutoxide, diaminedecane, and diamineoctane as precursors, a templated hexagonal zirconia matrix is synthesized and characterized by X-ray diffractometry and scanning electron microscopy. The adsorption capacity of such a matrix toward Co(II), Ni(II), Cu(II), and Zn(II) from aqueous solutions is studied. The adsorption affinity of the synthesized hexagonal templated zirconia toward the cations is Cu(II)>Zn(II) >Ni(II)>Co(II). It is also verified that the adsorption of the cations follows a Langmuir and not a Freundlich isotherm. All obtained isotherms are of type I, according to the IUPAC classification. The observed adsorption affinity sequence can be explained by taking into account the velocity constant for the substitution of water molecules into the cation coordination spheres, as well as the Irving-Williams series.

  1. Adsorption of Co(II), Ni(II), Cu(II), and Zn(II) on hexagonal templated zirconia obtained thorough a sol-gel process: the effects of nanostructure on adsorption features.

    PubMed

    de Farias, Robson F; do Nascimento, Ana A S; Bezerra, Cícero W B

    2004-09-01

    Using zirconium tetrabutoxide, diaminedecane, and diamineoctane as precursors, a templated hexagonal zirconia matrix is synthesized and characterized by X-ray diffractometry and scanning electron microscopy. The adsorption capacity of such a matrix toward Co(II), Ni(II), Cu(II), and Zn(II) from aqueous solutions is studied. The adsorption affinity of the synthesized hexagonal templated zirconia toward the cations is Cu(II)>Zn(II) >Ni(II)>Co(II). It is also verified that the adsorption of the cations follows a Langmuir and not a Freundlich isotherm. All obtained isotherms are of type I, according to the IUPAC classification. The observed adsorption affinity sequence can be explained by taking into account the velocity constant for the substitution of water molecules into the cation coordination spheres, as well as the Irving-Williams series. PMID:15276032

  2. Interstitial photodynamic therapy of canine prostate with meso-tetra-(m-hydroxyphenyl) chlorin and 5-aminolevulinic acid: a preliminary study

    NASA Astrophysics Data System (ADS)

    Chang, Shi-Chung; Buonaccorsi, Giovanni A.; MacRobert, Alexander J.; Bown, Stephen G.

    1996-01-01

    Photodynamic therapy (PDT) is proved to have potential for managing various malignancies. We investigated tissue biodistribution and photodynamic effects on a canine model in vivo using second generation photosensitizers, meso-tetra(m-hydroxyphenyl)chlorin (mTHPC) and 5-aminolaevulinic acid (ALA) to evaluate the feasibility and possible future application of PDT on the prostate. Using fluorescence microscopy, the optimal sensitization time of the prostate was between 24 - 72 hours with mTHPC and, 3 hours with ALA. After optimum time of sensitization, prostates of mature beagle were treated with laser at various sites by placing fiber interstitially under the guidance of transrectal ultrasound. The light dose for each treatment site was 100 J (100 mW for 1,000 seconds at the wavelength of 650 and 630 nm, respectively). With mTHPC, single laser fiber was able to induce organ confined PDT lesion as large as 20 by 18 by 18 mm in size. However, the PDT lesion with ALA was negligible 3 days after treatment. Physical distress manifested as urinary retention, poor appetite and body weigh loss, was more prominent with increasing number of treatment sites as a result of extensive prostatic swelling and urethral damages. However, these problems usually alleviated spontaneously 7 to 10 days after PDT. The characteristic histological changes were hemorrhagic necrosis and glandular destruction with preservation of interlobular collagen fibers. Urethral damage seen at the early stage healed by regeneration of urothelium in 4 weeks. We conclude that interstitial PDT with mTHPC is technically possible to produce extensive glandular necrosis in the normal prostate which heals safely and does not change the prostatic architecture. ALA, although it seems promising for bladder tumors, is much less effective than mTHPC on the prostate. With mTHPC, it might have the potential for treating prostate cancers localized in the periphery of the gland.

  3. DFT-D study of 14N nuclear quadrupolar interactions in tetra-n-alkyl ammonium halide crystals.

    PubMed

    Dib, Eddy; Alonso, Bruno; Mineva, Tzonka

    2014-05-15

    The density functional theory-based method with periodic boundary conditions and addition of a pair-wised empirical correction for the London dispersion energy (DFT-D) was used to study the NMR quadrupolar interaction (coupling constant CQ and asymmetry parameter ηQ) of (14)N nuclei in a homologous series of tetra-n-alkylammonium halides (C(x)H(2x+1))4N(+)X(-) (x = 1-4), (X = Br, I). These (14)N quadrupolar properties are particularly challenging for the DFT-D computations because of their very high sensitivity to tiny geometrical changes, being negligible for other spectral property calculations as, for example, NMR (14)N chemical shift. In addition, the polarization effect of the halide anions in the considered crystal mesophases combines with interactions of van der Waals type between cations and anions. Comparing experimental and theoretical results, the performance of PBE-D functional is preferred over that of B3LYP-D. The results demonstrated a good transferability of the empirical parameters in the London dispersion formula for crystals with two or more carbons per alkyl group in the cations, whereas the empirical corrections in the tetramethylammonium halides appeared to be inappropriate for the quadrupolar interaction calculation. This is attributed to the enhanced cation-anion attraction, which causes a strong polarization at the nitrogen site. Our results demonstrated that the (14)N CQ and ηQ are predominantly affected by the molecular structures of the cations, adapted to the symmetry of the anion arrangements. The long-range polarization effect of the surrounding anions at the target nitrogen site becomes more important for cells with lower spatial symmetry. PMID:24758512

  4. Bioactive surface modifications on inner walls of poly-tetra-fluoro-ethylene tubes using dielectric barrier discharge

    NASA Astrophysics Data System (ADS)

    Cho, Yong Ki; Park, Daewon; Kim, Hoonbae; Lee, Hyerim; Park, Heonyong; Kim, Hong Ja; Jung, Donggeun

    2014-03-01

    Bioactive surface modification can be used in a variety of medical polymeric materials in the fields of biochips and biosensors, artificial membranes, and vascular grafts. In this study, the surface modification of the inner walls of poly-tetra-fluoro-ethylene (PTFE) tubing was carried out to improve vascular grafts, which are made of biocompatible material for the human body in the medical field. Focus was centered on the cell attachment of the inner wall of the PTFE by sequential processes of hydrogen plasma treatment, hydrocarbon deposition, and reactive plasma treatment on the PFTE surface using micro plasma discharge. Micro plasma was generated by a medium-frequency alternating current high-voltage generator. The preliminary modification of PTFE was conducted by a plasma of hydrogen and argon gases. The hydrocarbon thin film was deposited on modified PTFE with a mixture of acetylene and argon gases. The reactive plasma treatment using oxygen plasma was done to give biocompatible functionality to the inner wall surface. The hydrophobic surface of bare PTFE is made hydrophilic by the reactive plasma treatment due to the formation of carbonyl groups on the surface. The reactive treatment could lead to improved attachment of smooth muscle cells (SMCs) on the modified PTFE tubing. Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurement were used for the analysis of the surface modification. The SMC-attached PTFE tube developed will be applicable to in vitro human vasculature-mimetic model systems, and to medical vascular grafts.

  5. Preparation and characterization of sterile sub-200 nm meso-tetra(4-hydroxylphenyl)porphyrin-loaded nanoparticles for photodynamic therapy.

    PubMed

    Konan, Yvette Niamien; Cerny, Radovan; Favet, Joselyne; Berton, Myriam; Gurny, Robert; Allémann, Eric

    2003-01-01

    A photosensitizer, meso-tetra(4-hydroxyphenyl)porphyrin, was incorporated into sub-150 nm nanoparticles using the emulsification-diffusion technique in order to perform sterilization by filtration using 0.22 microm membranes. The three selected polyesters (poly(D,L-lactide-co-glycolide), (50:50 PLGA, 75:25 PLGA) and poly(D,L-lactide (PLA)) for the nanoparticle production were all amorphous in nature and have similar molecular weights but different copolymer molar ratios. The influence of the copolymer molar ratio and the theoretical drug loading was investigated in terms of particle size, drug loading, entrapment efficiency and surface characteristics. With all the polymers used, sub-150 nm nanoparticles were produced with good reproducibility and narrow size distributions irrespective of both the polymer nature and the theoretical drug loading. After purification by cross-flow filtration, the nanoparticle suspensions were sterilized by membrane filtration and freeze-dried in the presence of a lyoprotectant (trehalose). For all types of nanoparticles, complete redispersion in various media could be obtained. All final freeze-dried products were refiltrable on a 0.22 microm membrane and were stable in terms of mean particle size and drug loading over a period up to 6 months. The effective drug loading increased at higher theoretical drug loading, the entrapment efficiency was however decreased. The same trend was observed with the three polyesters. The sterility of the final freeze-dried nanoparticles was confirmed by the results of the sterility testing which showed no bacterial contamination. PMID:12551712

  6. DFT-D study of 14N nuclear quadrupolar interactions in tetra-n-alkyl ammonium halide crystals.

    PubMed

    Dib, Eddy; Alonso, Bruno; Mineva, Tzonka

    2014-05-15

    The density functional theory-based method with periodic boundary conditions and addition of a pair-wised empirical correction for the London dispersion energy (DFT-D) was used to study the NMR quadrupolar interaction (coupling constant CQ and asymmetry parameter ηQ) of (14)N nuclei in a homologous series of tetra-n-alkylammonium halides (C(x)H(2x+1))4N(+)X(-) (x = 1-4), (X = Br, I). These (14)N quadrupolar properties are particularly challenging for the DFT-D computations because of their very high sensitivity to tiny geometrical changes, being negligible for other spectral property calculations as, for example, NMR (14)N chemical shift. In addition, the polarization effect of the halide anions in the considered crystal mesophases combines with interactions of van der Waals type between cations and anions. Comparing experimental and theoretical results, the performance of PBE-D functional is preferred over that of B3LYP-D. The results demonstrated a good transferability of the empirical parameters in the London dispersion formula for crystals with two or more carbons per alkyl group in the cations, whereas the empirical corrections in the tetramethylammonium halides appeared to be inappropriate for the quadrupolar interaction calculation. This is attributed to the enhanced cation-anion attraction, which causes a strong polarization at the nitrogen site. Our results demonstrated that the (14)N CQ and ηQ are predominantly affected by the molecular structures of the cations, adapted to the symmetry of the anion arrangements. The long-range polarization effect of the surrounding anions at the target nitrogen site becomes more important for cells with lower spatial symmetry.

  7. Antibacterial and anticancer activity of a series of novel peptides incorporating cyclic tetra-substituted C(α) amino acids.

    PubMed

    Hicks, Rickey P

    2016-09-15

    Eleven antimicrobial peptides (AMP) based on the incorporation of cyclic tetra substituted C(α) amino acids, as well as other unnatural amino acids were designed, synthesized and screened for in vitro activity against 18 strains of bacteria as well as 12 cancer cell lines. The AMPs discussed herein are derived from the following peptide sequence: Ac-GF(X)G(X)B(X)G(X)F(X)G(X)GB(X)BBBB-amide, X=any one of the following residues, A5c, A6c, Tic or Oic and B=any one of the following residues, Arg, Lys, Orn, Dpr or Dab. A diversity of in vitro inhibitory activity was observed for these AMPs. Several analogs exhibited single digit μM activity against drug resistant bacteria including; multiple drug resistant Mycobacterium tuberculosis, extremely drug resistant Mycobacterium tuberculosis and MRSA. The physicochemical properties of the basic amino acid residues incorporated into these AMPs seem to play a major role in defining antibacterial activity. Overall hydrophobicity seems to play a limited role in defining antibacterial activity. The ESKAPE pathogens were used to compare the activity of these AMPs to another family of synthetic AMPs incorporating the unnatural amino acids Tic and Oic. In most cases similarly substituted members of both families exhibited similar inhibitory activity against the ESKAPE pathogens. In specific cases differences in activity as high as 15 fold were observed between analogs. In addition four of these AMPs exhibited promising IC50 (<7.5μM) values against 12 different and diverse cancer cell lines. Five other AMPs exhibited promising IC50 (<7.5μM) values against selected cancer cell lines. PMID:27387357

  8. Antibacterial and anticancer activity of a series of novel peptides incorporating cyclic tetra-substituted C(α) amino acids.

    PubMed

    Hicks, Rickey P

    2016-09-15

    Eleven antimicrobial peptides (AMP) based on the incorporation of cyclic tetra substituted C(α) amino acids, as well as other unnatural amino acids were designed, synthesized and screened for in vitro activity against 18 strains of bacteria as well as 12 cancer cell lines. The AMPs discussed herein are derived from the following peptide sequence: Ac-GF(X)G(X)B(X)G(X)F(X)G(X)GB(X)BBBB-amide, X=any one of the following residues, A5c, A6c, Tic or Oic and B=any one of the following residues, Arg, Lys, Orn, Dpr or Dab. A diversity of in vitro inhibitory activity was observed for these AMPs. Several analogs exhibited single digit μM activity against drug resistant bacteria including; multiple drug resistant Mycobacterium tuberculosis, extremely drug resistant Mycobacterium tuberculosis and MRSA. The physicochemical properties of the basic amino acid residues incorporated into these AMPs seem to play a major role in defining antibacterial activity. Overall hydrophobicity seems to play a limited role in defining antibacterial activity. The ESKAPE pathogens were used to compare the activity of these AMPs to another family of synthetic AMPs incorporating the unnatural amino acids Tic and Oic. In most cases similarly substituted members of both families exhibited similar inhibitory activity against the ESKAPE pathogens. In specific cases differences in activity as high as 15 fold were observed between analogs. In addition four of these AMPs exhibited promising IC50 (<7.5μM) values against 12 different and diverse cancer cell lines. Five other AMPs exhibited promising IC50 (<7.5μM) values against selected cancer cell lines.

  9. TetraMabs: simultaneous targeting of four oncogenic receptor tyrosine kinases for tumor growth inhibition in heterogeneous tumor cell populations

    PubMed Central

    Castoldi, Raffaella; Schanzer, Jürgen; Panke, Christian; Jucknischke, Ute; Neubert, Natalie J.; Croasdale, Rebecca; Scheuer, Werner; Auer, Johannes; Klein, Christian; Niederfellner, Gerhard; Kobold, Sebastian; Sustmann, Claudio

    2016-01-01

    Monoclonal antibody-based targeted tumor therapy has greatly improved treatment options for patients. Antibodies against oncogenic receptor tyrosine kinases (RTKs), especially the ErbB receptor family, are prominent examples. However, long-term efficacy of such antibodies is limited by resistance mechanisms. Tumor evasion by a priori or acquired activation of other kinases is often causative for this phenomenon. These findings led to an increasing number of combination approaches either within a protein family, e.g. the ErbB family or by targeting RTKs of different phylogenetic origin like HER1 and cMet or HER1 and IGF1R. Progress in antibody engineering technology enabled generation of clinical grade bispecific antibodies (BsAbs) to design drugs inherently addressing such resistance mechanisms. Limited data are available on multi-specific antibodies targeting three or more RTKs. In the present study, we have evaluated the cloning, eukaryotic expression and purification of tetraspecific, tetravalent Fc-containing antibodies targeting HER3, cMet, HER1 and IGF1R. The antibodies are based on the combination of single-chain Fab and Fv fragments in an IgG1 antibody format enhanced by the knob-into-hole technology. They are non-agonistic and inhibit tumor cell growth comparable to the combination of four parental antibodies. Importantly, TetraMabs show improved apoptosis induction and tumor growth inhibition over individual monospecific or BsAbs in cellular assays. In addition, a mimicry assay to reflect heterogeneous expression of antigens in a tumor mass was established. With this novel in vitro assay, we can demonstrate the superiority of a tetraspecific antibody to bispecific tumor antigen-binding antibodies in early pre-clinical development. PMID:27578890

  10. Synthesis, magnetism and spectral studies of six defective dicubane tetranuclear {M4O6} (M = Ni(II), Co(II), Zn(II)) and three trinuclear Cd(II) complexes with polydentate Schiff base ligands.

    PubMed

    Jiang, Lin; Zhang, Dong-Yan; Suo, Jing-Jing; Gu, Wen; Tian, Jin-Lei; Liu, Xin; Yan, Shi-Ping

    2016-06-21

    A series of Ni(II), Co(II), Zn(II) and Cd(II) complexes with polytopic Schiff base ligands have been synthesized. The single-crystal X-ray crystallography results show that tetranuclear complexes have common face-shared defective dicubane cores, whereas trinuclear Cd(II) complexes are almost linear entities. Synthesis methods (solvent evaporation and hydrothermal synthesis), reaction conditions (pH, solvents and dosage) and coligands (azide, methanol, chloride and acetate) play vital roles in determining the final structure of the complexes and therefore their magnetic properties. In complexes , the terminal and central M(2+) ions are connected through mixed bridges, μ-phenoxido/μ1,1,1-X and μ-Oalphatic/μ1,1,1-X, while central two M(2+) ions are linked by double bridges, μ1,1,1-X (X = azido and methoxido groups for and respectively). For complex , two central Ni(II) ions are connected through two μ1,1,1-N3(-) which is relatively less reported. For complexes , there are two kinds of Cd(II), the centre Cd(II) ions are eight-coordinated with triangle dodecahedral geometries, while the two side Cd(II) ions are six-coordinated with trigonal prism geometries using chlorides or acetates as terminal ligands. Magnetic susceptibility measurements (χM) for compounds have been performed, and they reveal predominant ferromagnetic exchange interactions in Co(II) and Ni(II) tetramers. The photoluminescence studies show that the Zn(II) complex and three Cd(II) complexes have strong fluorescence, and the lifetimes are measured to be in the 10(2) nanosecond timescale. PMID:27230103

  11. Theoretical and experimental studies of two Co(II) and Ni(II) coordination complex with N,O donor 2-chloro-6-{[(4-hydroxy-3-methoxyphenyl)methylidene]amino}-4 nitrophenol ligand

    NASA Astrophysics Data System (ADS)

    Kusmariya, Brajendra S.; Tiwari, Sandeep; Tiwari, Anjali; Mishra, A. P.; Naikoo, Gowhar Ahmad; Pandit, Umar J.

    2016-07-01

    Here we report two mononuclear Co(II) and Ni(II) complexes of general formula [M(L)2(H2O)].2H2O; {M = CoII & NiII} derived from bidentate 2-chloro-6-{[(4-hydroxy-3-methoxyphenyl)methylidene]amino}-4 nitrophenol ligand (HL). These compounds were characterized by elemental analysis, spectral (FT-IR, electronic and 1H-NMR), molar conductance, thermal, PXRD, SEM and electrochemical studies. Distorted octahedral geometry was proposed around the metal center with ligand (HL). The PXRD and SEM analysis shows the crystalline nature of complexes. The broadening of diffraction peaks were explained in terms of domain size and the lattice strain according to Scherrer and Williamson-Hall method. TG of the synthesized complexes illustrates their general decomposition pattern and thermal stability. The kinetic and thermodynamic parameters viz. activation energy (E∗), pre-exponential factor (Z), entropy of activation (ΔS∗), enthalpy of activation (ΔH∗) and free energy of activation (ΔG∗) of degradation process were also evaluated using Coats-Redfern (C-R), Piloyan-Novikova (P-N) and Horowitz-Metzger (H-M) methods for both complexes assuming first order degradation. The optical band gap values of complexes were found to be in good agreement with calculated HOMO-LUMO energy gap (ΔE) and lie in semiconducting range. The cyclic voltammetric studies of synthesized compounds were carried out in order to examine their electrochemical behavior. In addition theoretical calculations by means of DFT at B3LYP level were incorporated to support the experimental findings.

  12. sup 31 P and sup 1 H NMR studies of the structure of enzyme-bound substrate complexes of lobster muscle arginine kinase: Relaxation measurements with Mn(II) and Co(II)

    SciTech Connect

    Jarori, G.K.; Ray, B.D.; Rao, B.D.N. )

    1989-11-28

    The paramagnetic effects of Mn(II) and Co(II) on the spin-lattice relaxation rates of {sup 31}P nuclei of ATP and ADP and of Mn(II) on the spin-lattice relaxation rate of the {delta} protons of arginine bound to arginine kinase from lobster tail muscle have been measured. Temperature variation of {sup 31}P relaxation rates in E-MnADP and E-MnATP yields activation energies ({Delta}E) in the range 6-10 kcal/mol. Thus, the {sup 31}P relaxation rates in these complexes are exchange limited and cannot provide structural information. However, the relaxation rates in E-CoADP and E-CoATP exhibit frequency dependence and {Delta}E values in the range 1-2 kcal/mol; i.e., these rates depend upon {sup 31}P-Co(II) distances. These distances were calculated to be in the range 3.2-4.5 {angstrom}, appropriate for direct coordination between Co(II) and the phosphoryl groups. The paramagnetic effect of Mn(II) on the {sup 1}H spin-lattice relaxation rate of the {delta} protons of arginine in the E-MnADP-Arg complex was also measured at three frequencies. From the frequency dependence of the relaxation rate an effective {tau}{sub C} of 0.6 ns has also been calculated, which is most likely to be the electron spin relaxation rate ({tau}{sub S1}) for Mn(II) in this complex. The distance estimated on the basis of the reciprocal sixth root of the average relaxation rate of the {delta} protons was 10.9 {plus minus} 0.3 {angstrom}.

  13. Synthesis of novel binary and ternary complexes derived from 1-(2-hydroxy benzoyl)-4-phenylthiosemicarbazide (L1) and 2,2‧-dipyridyl (L2) with CoII, CuII and ZnII salts

    NASA Astrophysics Data System (ADS)

    Azhari, Shaker J.; Mlahi, Mosaad R.; Al-Asmy, Ahmed A.; Mostafa, Mohsen M.

    2015-02-01

    The complexes derived the reactions of 1-(2-hydroxybenzoyl)-4-phenylthiosemicarbazide (L1) with MX2 (M = CoII, CuII and ZnII ions; X = Cl- in case of CoII and CuII ions, Cl- and Ac- in case of ZnII) in EtOH, were synthesized and characterized. The results suggested that the complexes have the general formulae, [Cu(L1-2H)(EtOH)(H2O)2]ṡH2O, [Co(L1-2H)(EtOH)(H2O)]ṡ2H2O and [Zn(L1-2H)(EtOH)]. Also, the ternary complexes, derived from the reactions 2,2‧-dipyridyl (L2) with the metals salts followed by adding a solution of the L1 were synthesized and having the general formulae, [Cu2(L2)(L1-2H)(H2O)(OH)2]ṡ1/2H2O, [Co(L2)(L1-2H)]ṡ1.5EtOHṡ3H2O and [Zn(L2)(L1-2H)]ṡEtOH. The binary and ternary complexes were characterized by elemental analyses, molar conductivities, spectral (IR, UV-Vis, 1H-NMR and mass), thermal and magnetic measurements. The existence of OH group in the ternary complexes was confirmed by IR spectra. The amounts of solvent were determined from the results of TGA. The biological activity for the ligand and two complexes were tested against DNA.

  14. (meso-5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetra­azacyclo­tetra­deca-4,11-diene)nickel(II) bis­[O,O′-bis(4-methyl­phen­yl) dithio­phosphate

    PubMed Central

    Xie, Bin; Xiang, Yang-Guang; Zou, Li-Ke; Chang, Xiu-Li; Ji, Chang-You

    2009-01-01

    In the title compound, [Ni(C16H32N4)](C14H14O2PS2)2 or [Ni(trans[14]dien)][S2P(OC6H4Me-4)2]2, where trans[14]dien is meso-5,7,7,12,14,14-hexa­methyl-1,4,8,11-tetra­azacyclo­tetra­deca-4,11-diene, the NiII ion lies across a centre of inversion and is four-coordinated in a relatively undistorted square-planar arrangement by the four N atoms of the macrocyclic ligand trans[14]dien. The two O,O′-di(4-methyl­phen­yl)dithio­phos­phates act as counter-ions to balance the charge. Important geometric data include Ni—N = 1.9135 (16) and 1.9364 (15) Å. PMID:21577413

  15. Single Pore Translocation of Folded, Double-Stranded, and Tetra-stranded DNA through Channel of Bacteriophage Phi29 DNA Packaging Motor

    PubMed Central

    Haque, Farzin; Wang, Shaoying; Stites, Chris; Chen, Li; Wang, Chi; Guo, Peixuan

    2015-01-01

    The elegant architecture of the channel of bacteriophage phi29 DNA packaging motor has inspired the development of biomimetics for biophysical and nanobiomedical applications. The reengineered channel inserted into a lipid membrane exhibits robust electrophysiological properties ideal for precise sensing and fingerprinting of dsDNA at the single-molecule level. Herein, we used single channel conduction assays to quantitatively evaluate the translocation dynamics of dsDNA as a function of the length and conformation of dsDNA. We extracted the speed of dsDNA translocation from the dwell time distribution and estimated the various forces involved in the translocation process. A ~35-fold slower speed of translocation per base pair was observed for long dsDNA, a significant contrast to the speed of dsDNA crossing synthetic pores. It was found that the channel could translocate both dsDNA with ~32% of channel current blockage and ~64% for tetra-stranded DNA (two parallel dsDNA). The calculation of both cross-sectional areas of the dsDNA and tetra-stranded DNA suggested that the blockage was purely proportional to the physical space of the channel lumen and the size of the DNA substrate. Folded dsDNA configuration was clearly reflected in their characteristic current signatures. The finding of translocation of tetra-stranded DNA with 64% blockage is in consent with the recently elucidated mechanism of viral DNA packaging via a revolution mode that requires a channel larger than the dsDNA diameter of 2 nm to provide room for viral DNA revolving without rotation. The understanding of the dynamics of dsDNA translocation in the phi29 system will enable us to design more sophisticated single pore DNA translocation devices for future applications in nanotechnology and personal medicine. PMID:25890769

  16. Single pore translocation of folded, double-stranded, and tetra-stranded DNA through channel of bacteriophage phi29 DNA packaging motor.

    PubMed

    Haque, Farzin; Wang, Shaoying; Stites, Chris; Chen, Li; Wang, Chi; Guo, Peixuan

    2015-01-01

    The elegant architecture of the channel of bacteriophage phi29 DNA packaging motor has inspired the development of biomimetics for biophysical and nanobiomedical applications. The reengineered channel inserted into a lipid membrane exhibits robust electrophysiological properties ideal for precise sensing and fingerprinting of dsDNA at the single-molecule level. Herein, we used single channel conduction assays to quantitatively evaluate the translocation dynamics of dsDNA as a function of the length and conformation of dsDNA. We extracted the speed of dsDNA translocation from the dwell time distribution and estimated the various forces involved in the translocation process. A ∼35-fold slower speed of translocation per base-pair was observed for long dsDNA, a significant contrast to the speed of dsDNA crossing synthetic pores. It was found that the channel could translocate both dsDNA with ∼32% of channel current blockage and with ∼64% for tetra-stranded DNA (two parallel dsDNA). The calculation of both cross-sectional areas of the dsDNA and tetra-stranded DNA suggested that the blockage was purely proportional to the physical space of the channel lumen and the size of the DNA substrate. Folded dsDNA configuration was clearly reflected in their characteristic current signatures. The finding of translocation of tetra-stranded DNA with 64% blockage is in consent with the recently elucidated mechanism of viral DNA packaging via a revolution mode that requires a channel larger than the dsDNA diameter of 2 nm to provide room for viral DNA revolving without rotation. The understanding of the dynamics of dsDNA translocation in the phi29 system will enable us to design more sophisticated single pore DNA translocation devices for future applications in nanotechnology and personal medicine.

  17. A special conjugated model around sp3 carbon atoms: density functional theory study on the homoaromatic electron delocalization and applications of benzo-fused tetra(triptycene)porphyrins.

    PubMed

    Qi, Dongdong; Zhang, Lijuan; Zhao, Luyang; Cai, Xue; Jiang, Jianzhuang

    2012-06-01

    The three-unit homoaromatic electron-delocalizing nature of the benzo-fused tetra(triptycene)porphyrins (TTPs) with a three-dimensional conjugated model is clarified using density functional theory studies. Due to the electron delocalization, the unidirectional photon-induced current of this kind of TTP molecular skeleton with a highest efficiency of about 90% in the range between 350 and 500 nm gives them great potential as efficient solar antenna collectors. In addition, their active triptycene cups fused at the central porphyrin core render possible potential application in host-guest chemistry.

  18. Hydrogen-Free Plasma-Enhanced Chemical Vapor Deposition of Silicon Dioxide Using Tetra-isocyanate-silane (Si(NCO) 4)

    NASA Astrophysics Data System (ADS)

    Idris, Irman; Sugiura, Osamu

    1995-06-01

    Deposition of silicon dioxide by plasma-enhanced chemical vapor deposition (PECVD) technique using tetra-isocyanate-silane (Si(NCO)4 : TICS) and oxygen for interlayer dielectric film application is proposed. Film properties strongly depend on the gas composition. The film which was deposited under an oxygen-rich condition was water-free after deposition. The film density, refractive index, resistivity, and dielectric constant were 2.3 g/cm3, 1.46, 5×1014 Ω·cm, and 3.6, respectively. The etch rate by buffered HF was 330 nm/min.

  19. Density and viscosity studies of symmetrical tetra- n-alkylammonium bromides in water-ethanol mixtures at 303.15 K1

    NASA Astrophysics Data System (ADS)

    Hasan, M.; Pawar, T. B.; Sawant, A. B.

    2010-03-01

    The densities and viscosities of tetra- n-alkylammonium bromides, R4NBr (R=CH3 to C4H9), NaBPh4 and NaBr have been measured in 0, 10, 30, 50, 70, 90, and 100 wt % ethanol + water at 303.15 K. From the densities, apparent and limiting partial molar volumes of the electrolytes and ions in these mixture have been evaluated. The viscosity data have been analyzed with the help of Jones-Dole equation and the viscosity B-coefficients have been determined. The viscosity B-coefficients are further split up in to their ionic contributions.

  20. 4-Chloro-N-methyl-2-(1,2,3,4-tetra­hydro­isoquinolin-1-yl)aniline

    PubMed Central

    Harrad, Mohamed Anouar; Valerga, Pedro; Puerta, M. Carmen; Ali, Mustapha Ait; Karim, Abdellah

    2010-01-01

    The racemic title compound, C16H17ClN2, shows a tetra­hydro­isoquinoline skeleton with a 4-chloro-N-methyl­aniline group linked to the C atom at position 1. The dihedral angle between the benzene rings is 85.82 (4)°. An intra­molecular N—H⋯N hydrogen bond occurs. In the crystal, mol­ecules are linked through inter­molecular C—H⋯π inter­actions. PMID:21589493