keyword
MENU ▼
Read by QxMD icon Read
search

Bis

keyword
https://www.readbyqxmd.com/read/28813053/copper-ii-benzimidazole-complexes-as-efficient-fluorescent-probes-for-l-cysteine-in-water
#1
Duraiyarasu Maheshwaran, Selvarasu Priyanga, Ramasamy Mayilmurugan
Copper(ii) complexes [Cu(L1)(H2O)2](SO3CF3)21 and [Cu(L2)(H2O)2](SO3CF3)22 based on 2,6-bis(benzimidazolyl)pyridine were synthesized and are reported herein as highly selective "turn-on" optical probes for l-cysteine. The Cu(ii)/Cu(i) redox potential of probe 1 (0.14 V vs. NHE) was lower than that of 2 (0.233 V vs. NHE) in water. The molecular structure of 2 adopted a square pyramidal geometry (τ = 0.2545), with the Cu-Npy bond (1.958 Å) of its middle pyridine unit being shorter than the other two Cu-Nbenzim bonds (Cu-N, 1...
August 16, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28813052/mixed-ligand-iridium-iii-complexes-as-photodynamic-anticancer-agents
#2
Yue Zheng, Liang He, Dong-Yang Zhang, Cai-Ping Tan, Liang-Nian Ji, Zong-Wan Mao
Many phosphorescent iridium complexes are potent candidates as photodynamic therapeutic agents. In this work, a series of mixed-ligand phosphorescent iridium complexes (Ir1: [Ir(L1)(bpy)Cl](PF6)2; Ir2: [Ir(L1)(ppy)Cl](PF6); Ir3: [Ir(L2)(bpy)Cl](PF6)2; Ir4: [Ir(L2)(ppy)Cl](PF6). L1 = 2,6-bis(2-benzimidazolyl)pyridine; bpy = 2,2'-bipyridine; L2 = 2,6-bis(1-methyl-benzimidazol-2-yl)pyridine; ppy = 2-phenylpyridine) have been synthesized and characterized. These complexes display high luminescence quantum yields and long phosphorescence lifetimes...
August 16, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28812891/catalytic-alkynylation-of-cyclic-acetals-and-ketals-enabled-by-synergistic-gold-i-trimethylsilyl-catalysis
#3
Matheo Berthet, Olivier Songis, Catherine Taillier, Vincent Dalla
A completely regioselective and challenging gold(I)-catalyzed ring-opening of cyclic 1,3-dioxolanes and dioxanes by trimethylsilyl alkynes to set diol-derived propargyl trimethylsilyl bis-ethers is reported. This unprecedented and not trivial transformation does not operate with the catalytic methodologies recently reported for catalytic alkynylation of acyclic acetals/ketals, and is uniquely enabled by the application of a recently introduced synergistic gold(I)-silicon catalysis concept capable of producing simultaneously catalytic amounts of two key players, a silicon-based Lewis superacid and a nucleophilic gold acetylide...
August 16, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28812744/benzene-centred-tripodal-diglycolamides-for-the-sequestration-of-trivalent-actinides-metal-ion-extraction-and-luminescence-spectroscopic-investigations-in-a-room-temperature-ionic-liquid
#4
Seraj Ahmad Ansari, Prasanta Kumar Mohapatra, Andrea Leoncini, Jurriaan Huskens, Willem Verboom
Three benzene-centred tripodal diglycolamide (Bz-T-DGA) ligands, where the diglycolamide (DGA) moieties are attached to a central benzene ring through ethylene spacers (LI), amide groups (LII) or ether linkages (LIII), were evaluated for their extraction behaviour towards trivalent actinide and lanthanide ions in a room temperature ionic liquid (RTIL), viz. 1-butyl-3-methylimidazolium bis(trifluoromethane)sulfonimide ([C4mim][Tf2N]). The extraction behaviour of these ligands in [C4mim][Tf2N] medium was compared with that obtained in the molecular solvent n-dodecane showing an opposite selectivity of LIII > LII > LIvs...
August 16, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28812350/green-solvent-processable-dopant-free-hole-transporting-materials-for-robust-and-efficient-perovskite-solar-cells
#5
Junwoo Lee, Mahdi Malekshahi Byranvand, Gyeongho Kang, Sung Y Son, Seulki Song, Guan-Woo Kim, Taiho Park
In addition to having proper energy levels and high hole mobility (μh) without the use of dopants, hole-transporting materials (HTMs) used in n-i-p-type perovskite solar cells (PSCs) should be processed using green solvents to enable environmentally friendly device fabrication. Although many HTMs have been assessed, owing to the limited solubility of HTMs in green solvents, no green-solvent-processable HTM has been reported to date. Here we report on a green-solvent-processable HTM, an asymmetric D-A polymer (asy-PBTBDT) that exhibits superior solubility even in the green solvent, 2-methylanisole, which is a known food additive...
August 16, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28812322/reactivity-of-silanes-with-tbuponop-ruthenium-dichloride-facile-synthesis-of-chloro-silyl-ruthenium-compounds-and-subsequent-reactivity
#6
James Matthew Boncella, Nickolas H Anderson, Aaron M Tondreau
The coordination of tBuPONOP (tBuPONOP = 2,6-bis(ditertbutylphosphinito)pyridine) to different ruthenium starting materials, to generate (tBuPONOP)RuCl2, was investigated. The 16-electron species (tBuPONOP)Ru(H)Cl was produced from the reaction of triethylsilane with (tBuPONOP)RuCl2. Reactions of (tBuPONOP)RuCl2 with both phenylsilane or diphenylsilane afforded the 16-electron hydrido-silyl species (tBuPONOP)Ru(H)(PhSiCl2) and (tBuPONOP)Ru(H)(Ph2SiCl), respectively. Reactions of all three of these complexes with silver triflate afforded the simple salt metathesis products of (tBuPONOP)Ru(H)(OTf), (tBuPONOP)Ru(H)(PhSiCl(OTf)), and (tBuPONOP)Ru(H)(Ph2Si(OTf))...
August 15, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28812072/critical-universality-and-asymmetry-of-ionic-solution-iodobenzene-1-decyl-3-methyl-imidazolium-bis-trifluorosulfonyl-imide
#7
Xiaoyi Tao, Tianxiang Yin, Weiguo Shen
The liquid-liquid coexistence curve, heat capacity in the critical and noncritical regions, and the turbidity in critical one-phase and two-phase regions of the binary solution {iodobenzene + 1-decyl-3-methylimidazolium bis(trifluorosulfonyl)imide ([C10mim][NTf2])} have been precisely measured. From the data collected in the critical region, the critical exponents α, β, γ and ν, as well as the universal critical amplitude ratios RB and X were obtained and were shown to agree well with their theoretical values for the 3D-Ising universality class, which further confirmed the 3D-Ising criticality of ionic solutions even in a very low relative permittivity solvent...
August 16, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28811186/identification-and-characterization-of-small-molecule-inhibitors-of-porcine-reproductive-and-respiratory-syndrome-virus
#8
Alyssa B Evans, Pengfei Dong, Hyelee Loyd, Jianqiang Zhang, George A Kraus, Susan Carpenter
Porcine reproductive and respiratory syndrome virus (PRRSV) is the etiological agent of PRRS, an economically significant disease of swine worldwide. PRRSV is poorly controlled by the currently available vaccines, and alternative control strategies are needed to help prevent the continual circulation of the virus. Previously, we developed a synthetic route for the natural compound atractylodinol and demonstrated anti-PRRSV activity in vitro. However, the synthetic route was inefficient and the yield was poor...
August 12, 2017: Antiviral Research
https://www.readbyqxmd.com/read/28810731/the-impact-of-hydrogen-bonding-on-the-dynamics-and-structure-of-protic-ionic-liquid-water-binary-mixtures
#9
Heather E Bailey, Yong-Lei Wang, Michael D Fayer
The orientational dynamics and microscopic liquid structure of a protic ionic liquid, 1-ethylimidazolium bis(trifluoromethylsulfonyl)imide (EhimNTf2), and its aprotic analogue, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EmimNTf2), were studied at various water concentrations using optical heterodyne-detected optical Kerr Effect (OHD-OKE) spectroscopy, linear infrared spectroscopy, and atomistic simulations. The OHD-OKE experiments essentially measure the orientational relaxation of the Ehim+ and Emim+ cations...
August 15, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28809813/molecular-mechanisms-underlying-inhibitory-binding-of-alkylimidazolium-ionic-liquids-to-laccase
#10
Jianliang Sun, Hao Liu, Wenping Yang, Shicheng Chen, Shiyu Fu
Water-miscible alkylimidazolium ionic liquids (ILs) are "green" co-solvents for laccase catalysis, but generally inhibit enzyme activity. Here, we present novel insights into inhibition mechanisms by a combination of enzyme kinetics analysis and molecular simulation. Alkylimidazolium cations competitively bound to the TI Cu active pocket in the laccase through hydrophobic interactions. Cations with shorter alkyl chains (C₂~C₆) entered the channel inside the pocket, exhibiting a high compatibility with laccase (competitive inhibition constant Kic = 3...
August 15, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28809800/effect-of-2-6-bis-1-hydroxy-1-1-diphenyl-methyl-pyridine-as-organic-additive-in-sulfide-nimop-%C3%AE-al%C3%A2-o%C3%A2-catalyst-for-hydrodesulfurization-of-straight-run-gas-oil
#11
Carlos Eduardo Santolalla-Vargas, Victor Santes, Erick Meneses-Domínguez, Vicente Escamilla, Agileo Hernández-Gordillo, Elizabeth Gómez, Felipe Sánchez-Minero, José Escobar, Leonardo Díaz, Oscar Goiz
The effect of 2,6-bis-(1-hydroxy-1,1-diphenyl-methyl) pyridine (BDPHP) in the preparation of NiMoP/γ-Al₂O₃ catalysts have been investigated in the hydrodesulfurization (HDS) of straight-run gas oil. The γ-Al₂O₃ support was modified by surface impregnation of a solution of BDPHP to afford BDPHP/Ni molar ratios (0.5 and 1.0) in the final composition. The highest activity for NiMoP materials was found when the molar ratio of BDPHP/Ni was of 0.5. X-ray diffraction (XRD) results revealed that NiMoP (0...
August 15, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28809499/copper-assisted-oxidative-trifluoromethylthiolation-of-2-3-allenoic-acids-with-agscf3
#12
Shen Pan, Yangen Huang, Xiu-Hua Xu, Feng-Ling Qing
The oxidative trifluoromethylthiolation of 2,3-allenoic acids with AgSCF3 in the presence of (NH4)2S2O8 and catalytic copper salt was investigated. A series of 4-aryl-2,3-allenoic acids underwent radical trifluoromethylthiolation/intramolecular cyclization to afford β-trifluoromethylthiolated butenolides, which were conveniently transformed into trifluoromethylthiolated furan derivatives. In contrast, 2-monosubstituted 2,3-allenoic acids were converted into the corresponding 3,4-bis(trifluoromethylthio)but-2-enoic-acids under similar reaction conditions...
August 15, 2017: Organic Letters
https://www.readbyqxmd.com/read/28809493/macroscopic-structural-compositions-of-%C3%AF-conjugated-polymers-combined-insights-from-solid-state-nmr-and-molecular-dynamics-simulations
#13
Anton Melnyk, Matthias Junk, Michael D McGehee, Bradley F Chmelka, Michael Ryan Hansen, Denis Andrienko
Molecular dynamics simulations are combined with solid-state NMR measurements to gain insight into the macroscopic structural composition of the π-conjugated polymer poly(2,5-bis(3-tetradecyl-thiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT). The structural and dynamical properties, as established by the NMR analyses, were used to test the local structure of three constitutient mesophases with: (i) crystalline backbones and side chains, (ii) lamellar backbones and disordered side chains, or (iii) amorphous backbones and side chains...
August 15, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28809474/a-nano-in-nano-approach-for-enzyme-immobilization-based-on-block-copolymers
#14
Finizia Auriemma, Claudio De Rosa, Anna Malafronte, Rocco Di Girolamo, Chiara Santillo, Yuri Gerelli, Giovanna Fragneto, Robert David Barker, Vincenzo Pavone, Ornella Maglio, Angela Lombardi
We have set-up a facile approach for fabrication of supports with tailored nanoporosity for immobilization of enzymes. To this aim block copolymers self-assembly has been used to prepare nanostructured thin films with well-defined architecture containing pores of tailorable size delimited by walls with tailorable degree of hydrophilicity. In particular, we have employed a mixture of polystyrene-block-poly(L-lactide) (PS-PLLA) and polystyrene-block-poly(ethylene oxide) (PS-PEO) diblock copolymers to generate thin films with a lamellar morphology consisting of PS lamellar do-mains alternating with mixed PEO/PLLA blocks lamellar domains...
August 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28809469/electrostatic-polysulfides-confinement-to-inhibit-redox-shuttle-process-in-the-lithium-sulfur-batteries
#15
Min Ling, Wenjun Yan, Ayako Kawase, Hui Zhao, Yanbao Fu, Vincent S Battaglia, Gao Liu
Cationic polymer can capture polysulfide ions and inhibit polysulfide shuttle effect in lithium sulfur (Li-S) rechargeable batteries, enhancing the Li-S battery cycling performance. The cationic poly[bis(2-chloroethyl) ether-alt-1,3-bis[3-(dimethylamino) propyl]urea] quaternized (PQ) with a high density quaternary ammonium cations can trap the lithium polysulfide through the electrostatic attraction between positively charged quaternary ammonium (R4N+) and negatively charged polysulfide (Sx2-). PQ binder based sulfur electrodes deliver much higher capacity and provide better stability than traditional polyvinylidene fluoride (PVDF) binder based electrodes in Li-S cells...
August 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28809454/palladium-catalysed-carbon-fluorine-and-carbon-hydrogen-bond-alumination-of-fluoroarenes-and-heteroarenes
#16
Mark Richard Crimmin, Wenyi Chen, Thomas Hooper, Andrew White, Jamues Ng
Through serendipitous discovery, a palladium bis(phosphine) complex was identified as a catalyst for the selective transformation of sp2C-F and sp2C-H bonds of fluoroarenes and heteroarenes to sp2C-Al bonds (19 examples, 1 mol% Pd loading). The carbon-fluorine bond functionalization reaction is highly selective for the formation of organoaluminum products in preference to hydrodefluorination products (selectivity = 4.4:1 to 27:1). Evidence is presented for a two step mechanism in which hydrodefluorination is followed by sp2C-H alumination...
August 15, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28808388/caesalpinia-crista-linn-induces-protection-against-dna-and-membrane-damage
#17
R Sunil Kumar, Ramesh Balenahalli Narasingappa, Chandrashekhar G Joshi, Talakatta K Girish, Ananda Danagoudar
BACKGROUND: Caesalpinia crista is a medicinal herb used to cure various ailments in subtropical and tropical regions of Southeast Asia. OBJECTIVE: The objective of this evaluation of C. crista against free radical induced DNA and erythrocyte damage. MATERIALS AND METHODS: The profiles of polyphenol and flavonoid were quantified through reversed-phase high-performance liquid chromatography. Free radical induced DNA and membrane damage were performed using H2O2 as oxidative agent...
July 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28808381/characterization-antibacterial-and-antioxidant-properties-of-silver-nanoparticles-synthesized-from-aqueous-extracts-of-allium-sativum-zingiber-officinale-and-capsicum-frutescens
#18
Gloria Aderonke Otunola, Anthony Jide Afolayan, Emmanuel Olusegun Ajayi, Samuel Wale Odeyemi
BACKGROUND: Herbal drug delivery is limited by poor solubility and bioavailability which can be overcome with suitable nanomaterials that will enhance their pharmacokinetics and performance. OBJECTIVE: This study aimed to analyze the synthesis, characterization, and biological activities of silver nanoparticles (AgNPs) from three spices. MATERIALS AND METHODS: AgNPs were prepared using 0.1 M silver nitrate and aqueous extracts of Allium sativum L...
July 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28806690/occurrence-and-distribution-of-halogenated-flame-retardants-in-an-urban-watershed-comparison-to-polychlorinated-biphenyls-and-organochlorine-pesticides
#19
Qian Wang, Barry C Kelly
Due to restrictions on polybrominated diphenyl ethers (PBDEs), market demand for alternative flame retardants is projected to increase, worldwide. Information regarding the environmental behavior of these compounds is limited. The present study involved field measurements of several alternative halogenated flame retardants (HFRs), along with PBDEs and legacy persistent organic pollutants (POPs) in surface water, bottom sediments and suspended particulate matter (SPM) within a highly urbanized watershed in Singapore...
August 11, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28806585/relationship-between-craving-and-plasma-leptin-concentrations-in-patients-with-cocaine-addiction
#20
Giovanni Martinotti, Chiara Montemitro, Gaia Baroni, Sara Andreoli, Flaminia Alimonti, Marco Di Nicola, Federico Tonioni, Lorenzo Leggio, Massimo di Giannantonio, Luigi Janiri
BACKGROUND: There is robust evidence indicating an overlap between neurobiological circuitry and pathways that regulate addictions and those that regulate appetite and food intake. Rodent work suggests a role of the appetitive peptide leptin in cocaine-seeking behaviours. The goal of this study was to investigate the possible relationship between plasma leptin concentrations and cocaine craving and use in patients seeking treatment for cocaine dependence. METHODS: Patients (N=43) with a DSM-IV diagnosis of cocaine dependence were studied before starting detoxification (baseline; T0) and then again 14days after (T1; only those patients who abstained from cocaine during the study)...
August 5, 2017: Psychoneuroendocrinology
keyword
keyword
5436
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"