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41.
M. Laura Carbajal Silvia L. Soto Espinoza Silvina N. Valdez Edgardo Poskus Eduardo E. Smolko Mariano Grasselli 《Reactive and Functional Polymers》2009,69(11):816-820
In this work, we describe the cografting of glycidyl methacrylate and dimethyl acrylamide onto a macroporous polysulfone polymer. Aminophenyl arsenical compounds were covalently attached to the copolymer through epoxy ring add-on reactions followed by a 2-mercaptoethanol activation. Thioredoxin and thioredoxin-fusion proteins were immobilized onto this surface and detected by specific antibody recognition. Preservation of native protein folding was confirmed by the detection of the enzymatic activity of an unstable fusion protein. Immobilized fusion protein onto the modified material maintains the enzymatic activity for a longer time, up to two weeks, against the free protein under the same storage conditions that remains active for 2 days. 相似文献
42.
Xuan Shen Hao Yang Xiu-Hua Hu Yan Xu Feng-Ling Wang Su Chen Dun-Ru Zhu 《Inorganic chemistry communications》2009,12(8):785-788
A series of new neutral iridium(III) complexes containing strong-field ancillary ligands, [Ir(ppy)2(PPh3)L] (ppy = 2-phenylpyridine, PPh3 = triphenylphosphine, L = NCS−, 1; , 2; NCO−, 3), have been synthesized and fully characterized by 1H NMR, IR, ESI mass spectral and elemental analysis. The crystal structure of 1 has been determined by X-ray analysis. The photoluminescence (PL) spectra of 1–3 show emission maxima at 477, 489 and 485 nm, respectively, corresponding to blue light-emitting of 1 and blue-green light-emitting of 2 and 3. PL quantum yields (PLQYs) of 1–3 are 0.39, 0.13 and 0.43, respectively. 相似文献
43.
Yuanbiao Huang Jianxin Chen Lisheng Chi Chunxia Wei Zhichun Zhang Zhongshui Li Aike Li Li Zhang 《应用聚合物科学杂志》2009,112(3):1486-1495
A series of different steric hindrance nickel(II) complexes 1 – 6 bearing 2,6‐bis(imino)pyridine ligands have been synthesized and characterized. The molecular structures of the complexes 3 – 5 were determined by X‐ray diffraction analysis. The coordination geometry around the nickel center of the complexes is either square pyramid for complexes 3 and 4 or trigonal bipyramid for complex 5 . All of the nickel complexes exhibit high catalytic activity for norbornene polymerization in the presence of MAO, although low activity for ethylene oligomerization and polymerization. The effects of the Al/Ni ratio, halogen, monomer concentration, temperature, and reaction time on activity of catalyst for norbornene polymerization and polymer microstructure were investigated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
44.
45.
Mara Dobroschke Yvonne Geldmacher Ingo Ott Dr. Melanie Harlos Lisa Kater Laura Wagner Ronald Gust Prof. Dr. William S. Sheldrick Prof. Dr. Aram Prokop Dr. 《ChemMedChem》2009,4(2):177-187
Whereas the cytostatic agents mer‐[RhX3(DMSO)(pp)] (X=Cl, Br; pp=phen, dpq) are considerably more potent than their facial isomers, this order is reversed for the analogous kinetically more inert IrIII polypyridyl complexes. The complexes induce specific apoptotic cell death in leukemia and lymphoma cells via the intrinsic mitochondrial pathway and cause negligible necrotic damage.
46.
Lennart Bunch Prof. Darryl S. Pickering Prof. Thierry Gefflaut Prof. Virginie Vinatier Dr. Virgil Helaine Ahmad Amir Birgitte Nielsen Anders A. Jensen Prof. 《ChemMedChem》2009,4(11):1925-1929
Subtype‐selective ligands are of great interest to the scientific community, as they provide a tool for investigating the function of one receptor or transporter subtype when functioning in its native environment. Several 4‐substituted (S)‐glutamate (Glu) analogues were synthesized, and altogether this approach has provided important insight into the structure–activity relationships (SAR) for ionotropic and metabotropic glutamate receptors (iGluRs and mGluRs), as well as the excitatory amino acid transporters (EAATs). In this work, three 4,4‐disubstituted Glu analogues 1 – 3 , which are hybrid structures of important 4‐substituted Glu analogues 4 – 8 , were investigated at iGluRs and EAATs. Collectively, their pharmacological profiles add new and valuable information to the SAR for the iGluRs and EAAT1–3. 相似文献
47.
Michel Stephan Damjan terk Barbara Mohar 《Advanced Synthesis \u0026amp; Catalysis》2009,351(17):2779-2786
Switching Knowles DiPAMP’s {DiPAMP=1,2‐bis[(o‐anisyl)(phenyl)phosphino]‐ ethane} MeO groups with i‐PrO ones led to the i‐Pr‐SMS‐Phos {i‐Pr‐SMS‐Phos=1,2‐bis[(o‐isoprop‐ oxyphenyl)(phenyl)phosphino]ethane} ligand which displayed a boosted catalyst activity coupled with an enhanced enantioselectivity in the rhodium(I)‐catalyzed hydrogenation of a wide‐range of representative olefinic substrates (dehydro‐α‐amido acids, itaconates, acrylates, enamides, enol acetates, α,α‐diarylethylenes, etc). The rhodium(I)‐(i‐Pr‐SMS‐Phos) catalytic profile was investigated revealing its structural attributes and robustness, and in contrast to the usual trend, 31P NMR analysis revealed that its methyl (Z)‐α‐acetamidocinnamate (MAC) adduct consisted of a reversed diastereomeric ratio of 1.4:1 in favour of the most reactive diastereomer. 相似文献
48.
The Heck reaction of iodobenzene and methyl acrylate was investigated with CO2-philic Pd complex catalysts having fluorous ponytails and the organic base triethylamine (Et3N) in the presence of CO2 under solventless conditions at 80 °C. The catalysts are not soluble in the organic phase in the absence of CO2 and the reaction occurs in a solid-liquid biphasic system. When the organic liquid mixture is pressurized by CO2, CO2 is dissolved into the organic phase and this promotes the dissolution of the Pd complex catalysts. As a result, the Heck reaction occurs homogeneously in the organic phase, which enhances the rate of reaction. This positive effect of CO2 pressurization competes with the negative effect that the reacting species are diluted by an increasing amount of CO2 molecules dissolved. Thus, the maximum conversion appears at a CO2 pressure of around 4 MPa under the present reaction conditions. The catalysts are separated in the solid granules by depressurization and are recyclable without loss of activity after washing with n-hexane and/or water. When the washing is made with hexane alone, the catalytic activity tends to increase on the repeated Heck reactions, probably due to the accumulation of such a base adduct as Et3NHI on the catalysts. When the washing is further made with water, however, the base adduct is taken off from the catalysts and they show similar activity levels in the repeated runs. The potential of CO2 pressure tunable heterogeneous/homogeneous reaction system has also been investigated for Sonogashira reactions of iodobenzene and phenylacetylene under similar conditions. 相似文献
49.
Peng Ren Na Xu Chen Chen Hai-Bin Song Wei Shi Peng Cheng 《Inorganic chemistry communications》2008,11(7):730-732
1D cobalt(II) and nickel(II) coordination polymers {[Co(dba)(H2O)4] · H2O}n (1) and {[Ni(dba)(H2O)4] · H2O}n (2) (H2dba = 2,5-dihydroxy-p-benzenediacetic acid) were synthesized under low temperature solvothermal condition. When 4,4′-bipyridine (bpy) was introduced to the synthetic systems of 1 and 2, respectively, two novel 2D coordination polymers {[Co(dba)(bpy)] · 0.5H2O}n (3) and [Ni(dba)(bpy)(H2O)2]n (4) with different structures were obtained. All of the compounds were characterized by elemental analysis, FT-IR, UV–Vis spectra and single crystal X-ray diffraction. 相似文献
50.
Amrane S De Cian A Rosu F Kaiser M De Pauw E Teulade-Fichou MP Mergny JL 《Chembiochem : a European journal of chemical biology》2008,9(8):1229-1234
DNA hairpin structures formed within a repeated tract might be a causative factor for triplet expansion observed in several debilitating diseases. We have designed and used a fluorescence resonance energy transfer (FRET) melting assay to screen for ligands that bind specifically to the CNG triplet repeats. Using this assay, we screened a panel of 33 chemicals that were previously designed to bind DNA or RNA secondary structures. Remarkably, we found that macrocyclic compounds, such as acridine dimers and trimers, exhibit interesting affinities and specificities for this motif. 相似文献