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921.
DA Lanfranchi E Cesar-Rodo B Bertrand HH Huang L Day L Johann M Elhabiri K Becker DL Williams E Davioud-Charvet 《Organic & biomolecular chemistry》2012,10(31):6375-6387
Improving the solubility of polysubstituted 1,4-naphthoquinone derivatives was achieved by introducing nitrogen in two different positions of the naphthoquinone core, at C-5 and at C-8 of menadione through a two-step, straightforward synthesis based on the regioselective hetero-Diels-Alder reaction. The antimalarial and the antischistosomal activities of these polysubstituted aza-1,4-naphthoquinone derivatives were evaluated and led to the selection of distinct compounds for antimalarial versus antischistosomal action. The Ag(II)-assisted oxidative radical decarboxylation of the phenyl acetic acids using AgNO(3) and ammonium peroxodisulfate was modified to generate the 3-picolinyl-menadione with improved pharmacokinetic parameters, high antimalarial effects and capacity to inhibit the formation of β-hematin. 相似文献
922.
The Friedel-Crafts reaction of (η(4)-tetraphenylcyclobutadiene)(η(5)-carbomethoxycyclopentadienyl)cobalt with acid chlorides/aluminum chloride resulted exclusively in para-phenyl acylation. Both monoacylated (1.1 equiv of RCOCl/AlCl(3)) and tetraacylated products (>4 equiv of RCOCl/AlCl(3)) were synthesized. Reaction of PhCC(o-RC(6)H(4)) (R = Me, i-Pr) with Na(C(5)H(4)CO(2)Me) and CoCl(PPh(3))(3) gave predominantly (η(4)-1,3-diaryl-2,4-diphenylcyclobutadiene)(η(5)-carbomethoxycyclopentadienyl)cobalt metallocenes (1,3-[trans] vs 1,2-[cis] selectivity up to 6:1). Conformational control of Friedel-Crafts reactions on the major isomers gave exclusively para-acylation of the unsubstituted phenyl groups. 相似文献
923.
Kremmer E Meyer K Grässer FA Flatley A Kösters M Luppa PB Krämer PM 《Analytical and bioanalytical chemistry》2012,402(2):989-995
Procalcitonin (PCT)—a diagnostic serum parameter for bacterial infection and sepsis—is of great interest in the field of biosensors
for point-of-care testing. Its detection needs specific biological recognition elements, such as antibodies. Herein, we describe
the development and characterization of rat monoclonal antibodies (mAbs) for PCT, and their application in enzyme-linked immunosorbent
assays (ELISAs) for the determination of PCT in patient serum samples. From about 50 mAbs, two mAbs, CALCA 2F3 and CALCA 4A6,
were selected as a pair with high affinity for PCT in sandwich immunoassays. Both mAbs could be used either as capture or
as detection mAb. They were Protein G-purified and biotinylated when used as detection mAb. The setup of two sandwich ELISAs
with standards of human recombinant (hr) PCT, using either CALCA 2F3 (assay A) or CALCA 4A6 (assay B) as capture mAbs and
the biotinylated mAbs CALCA 4A6 or CALCA 2F3, respectively, as detection mAbs, led to highly specific determinations of PCT
without cross-reactivity to calcitonin and katacalcin. Test midpoints (IC50) of both assays were determined for hrPCT standards in 4% (w/v) human serum albumin and found with 2.5 (assay A) and 2.7 μg L−1 (assay B). With both sandwich ELISAs a collection of eight patient serum samples have been determined in comparison to the
determination by the Elecsys BRAHMS PCT assay. Good correlations between our prototype ELISAs and the BRAHMS assay could be
demonstrated (R
2: assay A, 0.996 and assay B, 0.990). The use of these newly developed anti-PCT mAbs should find broad applications in immunosensors
for point-of-care diagnostics of sepsis and systemic inflammation processes. 相似文献
924.
Hsin-Fu Huang Markus Zahn Francois Peters Elisabeth Lemaire 《Journal of Electrostatics》2012,70(6):481-488
Analytical solutions to the continuum spin and linear velocities as well as the two-dimensional volume flow rate are solved and presented for negative electrorheological Poiseuille flows induced by internal micro-particle Quincke electrorotation using continuum anti-symmetric/couple stress theories with finite spin viscosities and small spin velocities. Theoretical predictions on the volume flow rate and linear velocity profile obtained from the continuum finite spin viscosity small spin velocity theory presented herein agree very well with the experimental measurements in the parametric regime of low or small driving pressure gradients as reported in current literature. 相似文献
925.
Cerulli Martina De Santis Marianna Gaar Elisabeth Wiegele Angelika 《4OR: A Quarterly Journal of Operations Research》2021,19(3):415-448
4OR - Alternating direction methods of multipliers (ADMMs) are popular approaches to handle large scale semidefinite programs that gained attention during the past decade. In this paper, we focus... 相似文献
926.
927.
Tian N Lenkeit D Pelz S Kourkoulos D Hertel D Meerholz K Holder E 《Dalton transactions (Cambridge, England : 2003)》2011,40(43):11629-11635
The structure-property correlations of a set of heteroleptic red- and green-emitting Ir(III) complexes with different temperature sensitivities and charge trapping capabilities are described, revealing superb performance in multi-layer phosphorescent organic light-emitting diodes (PhOLEDs) expressed by very high maximum luminous efficiencies up to 36.8 cd A(-1). Using 2-phenylpyridine and with 2-(naphthalen-1-yl)pyridine as the C^N ligand, the resulting red emitting complex featured a maximum luminous efficiency of 10.8 cd A(-1); one of the most excellent device performances within this class of red Ir(III) emitters. 相似文献
928.
Dynamics of intermediate filament assembly followed in micro-flow by small angle X-ray scattering 总被引:2,自引:0,他引:2
Brennich ME Nolting JF Dammann C Nöding B Bauch S Herrmann H Pfohl T Köster S 《Lab on a chip》2011,11(4):708-716
The assembly of intermediate filaments (IFs) is a complex process that can be recapitulated through a series of distinct steps in vitro. The combination of microfluidics and small angle X-ray scattering (SAXS) provides a powerful tool to investigate the kinetics of this process on the relevant timescales. Microfluidic mixers based on the principle of hydrodynamic focusing allow for precise control of the mixing of proteins and smaller reagents like ions. Here, we present a multi-layer device that prevents proteins from adsorbing to the channel walls by engulfing the protein jet with a fluid layer of buffer. To ensure compatibility with SAXS, the device is fabricated from UV-curable adhesive (NOA 81). To demonstrate the successful prevention of contact between the protein jet and the channel walls we measure the distribution of a fluorescent dye in the device by confocal microscopy at various flow speeds and compare the results to finite element method (FEM) simulations. The prevention of contact enables the investigation of the assembly of IFs in flow by gradually increasing the salt concentration in the protein jet. The diffusion of salt into the jet can be determined by FEM simulations. SAXS data are collected at different positions in the jet, corresponding to different salt concentrations, and they reveal distinct differences between the earliest assembly states. We find that the mean square radius of gyration perpendicular to the filament axis increases from 13 nm(2) to 58 nm(2) upon assembly. Thereby we provide dynamic structural data of a complex assembly process that was amenable up to now only by microscopic techniques. 相似文献
929.
3-(Hetero)aryl substituted indoles, 7-azaindoles, and pyrroles can be obtained in a very concise fashion via a one-pot Masuda borylation-Suzuki coupling sequence. The concise total syntheses of the marine natural products meridianins A (5) and G (4i) nicely illustrate the utility of this methodology. 相似文献
930.