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Yanai Nobuhiro - - 2012
Directional self-assembly with both positional and orientational order has been achieved by the self-assembly of metal-organic framework (MOF) colloids. In their Communication (DOI: 10.1002/anie.201109132), S. Granick and N. Yanai report the formation of well-defined clusters and hexagonal arrangements by directional facet-to-facet attraction between colloidal MOF crystals through simple van der ...
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Senapati Dulal - - 2012
This communication reports a unique way to tune the first order NLO properties of nanoparticles tremendously via organized assembly structures, through σ-bond conjugation.
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Aparicio Fátima - - 2012
Linear organogelators and , which self-assemble cooperatively into fibrillar structures, act as efficient crystal growth media for common pharmaceutical ingredients like ASP, CAF, IND and CBZ.
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Solvent-dependent amplification of chirality in assemblies of porphyrin trimers based on benzene ...
Veling Nico - - 2012
Self-assembling achiral and chiral porphyrin trimers based on benzene tricarboxamide exhibit amplification of chirality only in solvents in which the assemblies are dynamic enough to rearrange their constituting components.
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Walker Sophie - - 2012
As tau aggregation likely plays a role in a number of neurodegenerative diseases, understanding the processes that affect tau aggregation is of considerable importance. One factor that has been shown to influence tau's aggregation propensity is the oxidation state of the protein itself. Tau protein, which contains two naturally occurring ...
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Kumatani Akichika - - 2012
A facile solution process for the fabrication of organic single crystal semiconductor devices which meets the demand for low-cost and large-area fabrication of high performance electronic devices is demonstrated. In this paper, we develop a bottom-up method which enables direct formation of organic semiconductor single crystals at selected locations with ...
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Rao Koya Prabhakara - - 2011
The donor-acceptor-donor (D-A-D) conjugated molecules 1,4-bis(diarylaminophenylethynyl)anthraquinone (1,4-Am(2) Aq) and 1,4-bis(ferrocenylethynyl)anthraquinone (1,4-Fc(2) Aq), undergo a double proton cyclization reaction with bis(trifluoromethanesulfone)imide acid (TFSIH) to yield 1,4-bis(diarylaminophenyl or ferrocenyl) dipyrylium salts [1,4-R(2) Pyl(2) ](TFSI)(2) (R=Am or Fc) with novel planar pentacyclic structures similar to the aromatic benzo[e]pyrene-type skeleton. [1,4-Am(2) Pyl(2) ](TFSI)(2) could ...
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Kamdem Ramsay S T - - 2011
Canarene (1), a triterpene with an unprecedented carbon backbone, was isolated from Canarium schweinfurthii . It is the first member of a new class of triterpenoids, for which the name "canarane'' is proposed. 1 showed weak α-glucosidase inhibitory activity, and its structure was unambiguously deduced by single-crystal X-ray diffraction.
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Yang Jun-Li - - 2011
An extract of the rhizomes of CYPERUS ROTUNDUS L. afforded two new sesquiterpenoids ( 2 and 3) with rearranged secoeudesmane and germacrane skeletons, and a new 9,10- SECO-cycloartane triterpenoid ( 9), as well as seven previously reported terpenoids, including a monoterpenoid ( 1), five sesquiterpenoids ( 4- 8) with guaiane, patchoulane, ...
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Wu Weibing - - 2011
In the title compound, C(30)H(35)B(2)NO(4), the carbazole skeleton is essentially planar (r.m.s. deviation for all non-H atoms = 0.035 Å), and is oriented at a dihedral angle of 65.0 (3)° with respect to the adjacent phenyl ring.
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Ingavat Nattha - - 2011
A novel sesquiterpenoid, asperaculin A (1), possessing a novel [5,5,5,6]fenestrane ring system, was isolated from the marine-derived fungus Aspergillus aculeatus CRI323-04. The structure of asperaculin A (1) was established by analysis of spectroscopic data. The name aspergillane is proposed for the sesquiterpene skeleton in asperaculin A (1).
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Liu Lei-Lei - - 2011
Four new polyacetylenes, namely chrysindins A-D ( 1- 4), together with 6 known polyacetylenes, were isolated from the flowers of CHRYSANTHEMUM INDICUM. Their structures were established on the basis of comprehensive spectroscopic analyses. Chrysindins A ( 1) and B ( 2) bear a novel carbon skeleton.
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Zhao Yue - - 2011
Analyte-induced formation of partial duplexes was used for biosensor development with cocaine as a model. The cocaine-aptamer interaction resulted in formation of a partial double strand section in the aptamer, where Ru(phen)(3)(2+) was intercalated for electrochemiluminescent analysis of cocaine.
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Röhrich Anika - - 2011
New macrocyclic 1,4,8,11-tetraazacyclotetradecane (cyclam) derivatives with 1, 2 and 4 neurotensin(8-13) units 4, 5 and 7 have been synthesized. Compounds 4 and 5 were prepared by the reaction of non-stabilized neurotensin(8-13) and cyclamtetrapropionic acid 2 using 1-ethyl-3-(3-dimethylaminocarbonyl)carbodiimide-hydrochloride and N-hydroxysulfosuccinimide. The tetrameric compound 7 was synthesized by Michael addition of neurotensin(8-13) ...
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Nelson Hannah C - - 2011
The objective of this project was to investigate the trends of changes in the crystal morphology of cocaine in the presence of the common adulterants, caffeine and lidocaine HCl. By performing gold chloride microcrystal tests on samples of cocaine with adulterants at 10, 20, and 50% concentrations, trends in ...
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Liu Dingbin - - 2011
In recent years, gold nanoparticles (AuNPs) have drawn considerable research attention in the fields of catalysis, drug delivery, imaging, diagnostics, therapy and biosensors due to their unique optical and electronic properties. In this review, we summarized recent advances in the development of AuNP-based colorimetric and fluorescent assays for ions including ...
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Tanaka Naonobu - - 2011
Two new steroidal alkaloids possessing a cevanine-type skeleton, veramadines A (1) and B (2), were isolated from the aerial parts of Veratrum maackii var. japonicum. The structures of 1 and 2 were elucidated on the basis of their spectroscopic data.
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Helz George R - - 2011
An extraordinary affinity of MoS₄²⁻ for Cu accounts for Mo-induced Cu deficiency in ruminants (molybdenosis) and offers an approach to treating Wilson's disease in humans. Evidence of thiomolybdates in sulfidic natural waters, and possibly even as metastable traces in oxic natural waters, raises the question of how Cu-Mo affinity might ...
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Cheng Shi-Yie - - 2011
Capilloquinol (1), possessing an unprecedented farnesyl quinoid skeleton, was isolated from the Dongsha Atoll soft coral Sinularia capillosa. The structure of capilloquinol was elucidated by extensive analysis of spectroscopic data. The cytotoxicity and antiviral activity against human cytomegalovirus of 1 was evaluated in vitro.
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Sperotto Elena - - 2010
The copper-mediated aromatic nucleophilic substitution reactions developed by Fritz Ullmann and Irma Goldberg required stoichiometric amounts of copper and very high reaction temperatures. Recently, it was found that addition of relatively cheap ligands (diamines, aminoalcohols, diketones, diols) made these reactions truly catalytic, with catalyst amounts as low as 1 mol% ...
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Chen Shui-Sheng - - 2011
A highly stable copper(II) microporous framework with cylindrical channels constructed from 1,4-di(1H-imidazol-4-yl)benzene (H(2)L) and CuCl(2)·2H(2)O is composed of Cu(II)-imidazolate tubes interconnected by the 1,4-phenylene group of L(2-), and shows temperature dependent selective gas sorption properties.
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Chufán Eduardo E - - 2010
Peptidylglycine α-hydroxylating monooxygenase (PHM) catalyzes the stereospecific hydroxylation of the Cα of C-terminal glycine-extended peptides and proteins, the first step in the activation of many peptide hormones, growth factors, and neurotransmitters. The crystal structure of the enzyme revealed two nonequivalent Cu sites (Cu(M) and Cu(H)) separated by ∼11 Å. In ...
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Ando Koji - - 2010
Structural and energetic reorganizations in redox reaction of type 1 copper proteins are studied by density functional and ab initio molecular orbital calculations. Model complexes of the active site with varying number of ligands, from Cu(SCH(3))(0/+) to Cu(SCH(3))(Im)(2)(S(CH(3))(2))(0/+), where Im denotes imidazole, are investigated. Following the findings of structural instability ...
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Oliveira Elisabete - - 2010
Three new compounds bearing furyl, aryl, or thienyl moieties linked to an imidazo-crown ether system (1, 2, and 3) were synthesized and fully characterized by elemental analysis, infrared, UV-vis absorption, and emission spectroscopy, X-ray crystal diffraction, and MALDI-TOF-MS spectrometry. The interaction toward metal ions (Ca(2+), Cu(2+), Ni(2+), and Hg(2+)) and ...
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Hansson Mattias D - - 2011
Ferrochelatase catalyzes the insertion of Fe(2+) into protoporphyrin IX. The enzymatic product heme (protoheme IX) is a well-known cofactor in a wide range of proteins. The insertion of metal ions other than Fe(2+) occurs rarely in vivo, but all ferrochelatases that have been studied can insert Zn(2+) at a good ...
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Safin Damir A - - 2010
Deprotonation of the N-thiophosphorylated thioureas RC(S)NHP(S)(OiPr)(2) (R = Me(2)N, HL(I); iPrNH, HL(II); 2,6-Me(2)C(6)H(3)NH, HL(III), 2,4,6-Me(3)C(6)H(2)NH, HL(IV), aza-15-crown-5, HL(V)) and reaction with CuI or Cu(NO(3))(2) in aqueous EtOH leads to the polynuclear complexes [Cu(4)(L(I)-S,S')(4)], [Cu(8)(L(II)-S,S')(8)], and [Cu(3)(L(III-V)-S,S')(3)]. The structures of these compounds were investigated by IR, (1)H, (31)P{(1)H} NMR, UV-vis spectroscopy ...
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Gomila Antoine - - 2010
We report the self-induced "electroclick" immobilization of the [Cu(II)(6-ethynyl-TMPA)(H(2)O)](2+) complex, by its simple electro-reduction, onto a mixed azidoundodecane-/decane-thiol modified gold electrode. The redox response of the grafted [Cu(II/I)(TMPA)] at the modified electrode is fully reversible indicating no Cu coordination change and a fast electron transfer.
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Cheong Wai Yeng - - 2010
Temperature programmed desorption methods have been used to probe the enantioselectivity of achiral Cu(100), Cu(110), and Cu(111) single crystal surfaces modified by chiral organic molecules including amino acids, alcohols, alkoxides, and amino-alcohols. The following combinations of chiral probes and chiral modifiers on Cu surfaces were included in this study: propylene ...
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Morita Hiroyuki - - 2010
Curcuminoid synthase (CUS) from Oryza sativa is a plant-specific type III polyketide synthase (PKS) that catalyzes the remarkable one-pot formation of the C(6)-C(7)-C(6) diarylheptanoid scaffold of bisdemethoxycurcumin, by the condensation of two molecules of 4-coumaroyl-CoA and one molecule of malonyl-CoA. The crystal structure of O. sativa CUS was solved at ...
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Sun Yi - - 2010
Five new dinuclear Cu(II) complexes were designed and synthesized, using hypocrellin B, a naturally occurring photosensitizer that has received extensive studies as promising photodynamic therapy (PDT) agent, as bridging ligand, and five kinds of diimine ligands, including 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 3,4,7,8-tetramethyl-1,10-phenanthroline (tmp), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq), and dipyrido[3,2-a:2',3'-c]phenazene (dppz), as terminal ...
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Zhou Xiao-Ping - - 2010
This paper aims to illustrate the rich potential of the thioether-carboxyl combination in generating coordination networks with tunable and interesting structural features. By simply varying the ratio between Cu(NO(3))(2) and the bifunctional ligand tetrakis(methylthio)benzenedicarboxylic acid (TMBD) as the reactants, three coordination networks can be hydrothermally synthesized in substantial yields, which ...
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Dutta Daipayan - - 2010
Two novel organic-inorganic hybrid tungsto- and molybdo-telurates having formula [{Na(4)(H(2)O)(14)}{Cu(gly)}(2)][TeMo(6)O(24)] (1){gly = glycine} and [{Cu(en)(2)}(3){TeW(6)O(24)}]·6H(2)O {en = ethyline-diamine} (2) based on Anderson type heteropolyoxometalates (POMs) have been synthesized and characterized by X-ray crystallography. Common structural feature of both 1 and 2 is the presence of a unique 1D open rack-like ...
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Furlan Sara - - 2010
The coordination of copper to the amyloid-β (1-16) (Aβ) peptide has been investigated because of its relevance for understanding Cu redox activity when the ion is embedded in peptides involved in neurodegenerative diseases. In this work, several reasonable models of Cu(+) coordination were built on the basis of experimental information ...
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Siluvai Gnana S - - 2011
Sco is a red copper protein that plays an essential yet poorly understood role in the metalation of the Cu(A) center of cytochrome oxidase, and is stable in both the Cu(I) and Cu(II) forms. To determine which oxidation state is important for function, we constructed His135 to Met or selenomethionine ...
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Kokalj Anton - - 2010
Three corrosion inhibitors for copper-3-amino-1,2,4-triazole (ATA), benzotriazole (BTAH), and 1-hydroxybenzotriazole (BTAOH)-were investigated by corrosion experiments and atomistic computer simulations. The trend of corrosion inhibition effectiveness of the three inhibitors on copper in near-neutral chloride solution is determined experimentally as BTAH ≳ ATA ≫ BTAOH. A careful analysis of the results ...
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Liu Yunlong - - 2011
A new rhodamine B-based dual-function chromo- and fluorogenic probe for Cu(2+) and ClO(-) has been designed, synthesized, and characterized. The probe comprises a spectroscopic unit of rhodamine B and a Cu(2+)-specific chelating unit of pyridinecarboxamide as well as a ClO(-)-specific reactive moiety of diacylhydrazine, and is a highly selective and ...
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Kang Peng - - 2010
N,N,N',N'-tetramethylethylenediamine (TMED), the simplest and most extensively used peralkylated diamine ligand, is conspicuously absent from those known to form a bis(μ-oxo)dicopper(III) (O) species, [(TMED)(2)Cu(III)(2)(μ(2)-O)(2)](2+), upon oxygenation of its Cu(I) complex. Presented here is the characterization of this O species and its reactivity toward exogenous substrates. Its formation is complicated both ...
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Smeets Pieter J - - 2010
The reactive oxidizing species in the selective oxidation of methane to methanol in oxygen activated Cu-ZSM-5 was recently defined to be a bent mono(μ-oxo)dicopper(II) species, [Cu(2)O](2+). In this communication we report the formation of an O(2)-precursor of this reactive site with an associated absorption band at 29,000 cm(-1). Laser excitation ...
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Donoghue Patrick J - - 2010
Insight into copper-oxygen species proposed as intermediates in oxidation catalysis is provided by the identification of a Cu(II)-superoxide complex supported by a sterically hindered, pyridinedicarboxamide ligand. A tetragonal, end-on superoxide structure is proposed based on DFT calculations and UV-vis, NMR, EPR, and resonance Raman spectroscopy. The complex yields a trans-1,2-peroxodicopper(II) ...
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Sarell Claire J - - 2010
A role for Cu(2+) ions in Alzheimer disease is often disputed, as it is believed that Cu(2+) ions only promote nontoxic amorphous aggregates of amyloid-β (Aβ). In contrast with currently held opinion, we show that the presence of substoichiometric levels of Cu(2+) ions in fact doubles the rate of production ...
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Kabehie Sanaz - - 2010
Heteroleptic copper compounds have been designed and synthesized on solid supports. Chemical redox agents were used to change the oxidation state of the SiO(2)-immobilized heteroleptic copper compounds from Cu(I) to Cu(II) and then back to Cu(I). Optical spectroscopy of a dimethyl sulfoxide suspension demonstrated the reversibility of the Cu(I)/Cu(II) SiO(2)-immobilized ...
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Freedman Danna E - - 2010
Structural characterization, exploiting X-ray scattering differences at elemental absorption edges, is developed to quantitatively determine crystallographic site-specific metal disorder. We apply this technique to the problem of Zn-Cu chemical disorder in ZnCu(3)(OH)(6)Cl(2). This geometrically frustrated kagomé antiferromagnet is one of the best candidates for a spin-liquid ground state, but chemical ...
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Binolfi Andrés - - 2010
The aggregation of alpha-synuclein (AS) is a critical step in the etiology of Parkinson's disease (PD). A central, unresolved question in the pathophysiology of PD relates to the role of AS-metal interactions in amyloid fibril formation and neurodegeneration. Our previous works established a hierarchy in alpha-synuclein-metal ion interactions, where Cu(II) ...
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Sun Bao-Zhen - - 2010
The possible reaction mechanisms for CO oxidation on the perfect Cu(2)O(111) surface have been investigated by performing periodic density functional theoretical calculations. We find that Cu(2)O(111) is able to facilitate the CO oxidation with different mechanisms. Four possible mechanisms are explored (denoted as M(ER1), M(ER2), M(LH1), and M(LH2), respectively): M(ER1) ...
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Révész Agnes - - 2010
Electrospray ionization of dilute aqueous solutions of copper(II) chloride-containing traces of pyridine (py) as well as ammonia permits the generation of the gaseous ions (py)(2) Cu(+) and (py)(2) CuCl(+) , of which the latter is a formal copper(II) compound, whereas the former contains copper(I). Collision-induced dissociation of the mass-selected ions ...
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Wright Ashley M - - 2010
The synthesis and characterization of a {CuNO}(10) complex, namely, [Cu(CH(3)NO(2))(5)(NO)][PF(6)](2), has been achieved by the addition of [NO][PF(6)] to copper metal powder in the presence of nitromethane. In the solid state, this complex exhibits a bent Cu-N-O moiety [Cu-N-O = 121.0(3)°] and a long Cu-N bond. This complex readily reacts ...
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Lebrun Jérémie D - - 2011
Metal effect on the enzyme secretion in fungi is usually related to total concentrations but not to bioavailable metal species. In this work, we aimed at enhancing the secretion of lignin-modifying oxidoreductases in Trametes versicolor by favouring the bioavailability of essential metals. For this purpose, the fungus was exposed to ...
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Ruthstein Sharon - - 2010
Herein, we identify the coordination environment of Cu²(+) in the human α1-glycine receptor (GlyR). GlyRs are members of the pentameric ligand-gated ion channel superfamily (pLGIC) that mediate fast signaling at synapses. Metal ions like Zn²(+) and Cu²(+) significantly modulate the activity of pLGICs, and metal ion coordination is essential for ...
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Lancaster Kyle M - - 2010
Redox and spectroscopic (electronic absorption, multifrequency electron paramagnetic resonance (EPR), and X-ray absorption) properties together with X-ray crystal structures are reported for the type 2 Cu(II) C112D/M121E variant of Pseudomonas aeruginosa azurin. The results suggest that Cu(II) is constrained from interaction with the proximal glutamate; this structural frustration implies a ...
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Cerón Maria Luisa - - 2011
A theoretical study of methanol decomposition using a model representing the initial step of the reaction CH₃OH + CuO → CH₂O + H₂O + Cu is presented. Theoretical calculations using B3LYP/6-31 G along with Lanl2DZ pseudopotentials on metallic centers were performed and the results discussed within the framework of the ...
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