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51.
Niculina D. Bogdan Dr. Mihaela Matache Veronika M. Meier Dr. Cristian Dobrotă Dr. Ioana Dumitru Gheorghe D. Roiban Dr. Daniel P. Funeriu Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(7):2170-2180
Herein we describe the design and synthesis of the first series of di‐functional ligands for the directed construction of inorganic‐protein frameworks. The synthesized ligands are composed of a metal‐ion binding moiety (terpyridine‐based) conjugated to an epoxysuccinyl peptide, known to covalently bind active cysteine proteases through the active‐site cysteine. We explore and optimize two different conjugation chemistries between the di‐functionalized metal‐ion ligand and the epoxysuccinyl‐containing peptide moiety: peptide‐bond formation (with limited success) and CuI‐catalysed click chemistry (with good results). Further, the complexation of the synthesized ligands with FeII and NiII ions is investigated: the di‐functional ligands are confirmed to behave similarly to the parent terpyridine. As designed, the peptidic moiety does not interfere with the complexation reaction, in spite of the presence of two triazole rings that result from the click reaction. ES‐MS together with NMR and UV/Vis studies establish the structure, the stoichiometry of the complexation reactions, as well as the conditions under which chemically sensitive peptide‐containing polypyridine ligands can undergo the self‐assembly process. These results establish the versatility of our approach and open the way to the synthesis of di‐functional ligands containing more elaborated polypyridine ligands as well as affinity labels for different enzyme families. As such, this paper is the first step towards the construction of robust supramolecular species that cover a size‐regime and organization level previously unexplored. 相似文献
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53.
Pavel Jandera Jiří Urban Veronika Škeříková Pavel Langmaier Romana Kubíčková Josef Planeta 《Journal of chromatography. A》2010,1217(1):22-33
We prepared hybrid particle-monolithic polymethacrylate columns for micro-HPLC by in situ polymerization in fused silica capillaries pre-packed with 3–5 μm C18 and aminopropyl silica bonded particles, using polymerization mixtures based on laurylmethacrylate–ethylene dimethacrylate (co)polymers for the reversed-phase (RP) mode and [2-(methacryloyloxy)ethyl]-dimethyl-(3-sulfopropyl) zwitterionic (co)polymers for the hydrophilic interaction (HILIC) mode. The hybrid particle-monolithic columns showed reduced porosity and hold-up volumes, approximately 2–2.5 times lower in comparison to the pure monolithic columns prepared in the whole volume of empty capillaries. The elution volumes of sample compounds are also generally lower in comparison to packed or pure monolithic columns. The efficiency and permeability of the hybrid columns are intermediate in between the properties of the reference pure monolithic and particle-packed columns. The chemistries of the embedded solid particles and of the interparticle monolithic moiety in the hybrid capillary columns contribute to the retention to various degrees, affecting the selectivity of separation. Some hybrid columns provided improved separations of proteins in comparison to the reference particle-packed columns in the reversed-phase mode. Zwitterionic hybrid particle-monolithic columns show dual mode retention HILIC/RP behaviour depending on the composition of the mobile phase and allow separations of polar compounds such as phenolic acids in the HILIC mode at lower concentrations of acetonitrile and, often in shorter analysis time in comparison to particle-packed and full-volume monolithic columns. 相似文献
54.
Simone Göttlich Simon Hoher Patrick Schindler Veronika Schleper Alexander Verl 《Applied Mathematical Modelling》2014
In this paper a model comparison approach based on material flow systems is investigated that is divided into a microscopic and a macroscopic model scale. On the microscopic model scale particles are simulated using a model based on Newton dynamics borrowed from the engineering literature. Phenomenological observations lead to a hyperbolic partial differential equation on the macroscopic model scale. Suitable numerical algorithms are presented and both models are compared numerically and validated against real-data test settings. 相似文献
55.
Boris Remenec Silvia Dulanská Veronika Gardoňová Ľubomír Mátel 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):907-910
This paper describes a rapid method of 94Nb pre-concentration, separation and purification by using cation and anion exchange resins. The method is suitable for analyzing highly contaminated radioactive waste samples in a relatively short time and high decontamination factors. The use and effectiveness of the method was successfully tested by analysis of samples from nuclear reactor parts such as control rod drive shaft, shielding cassettes, neutron in-core measurement channels (KNI), pressure vessel construction material and fuel cassette construction material samples. 相似文献
56.
Edit Csapó Péter Buglyó Nóra Veronika Nagy M. Amélia Santos Alma Corona Etelka Farkas 《Polyhedron》2010
Two histidinehydroxamic acid derivatives (N-methyl-histidinehydroxamic acid, N-Me-Hisha and Z-histidinehydroxamic acid, Z-Hisha) have been synthesized and their complexation with Cu2+-, Ni2+- and Zn2+-ions has been studied by using pH-potentiometric, UV–Vis, CD, 1H NMR, EPR and ESI-MS methods. Both of the two new derivatives contain one donor atom less compared to the histidinehydroxamic acid (Hisha). In the case of N-Me-Hisha the hydroxamate-N as donor is eliminated, while the coordination of the amino-N of Z-Hisha is not possible at all. 相似文献
57.
Veronika Nagy Erika Turcsi Péter Molnár Zoltán Szabó József Deli 《Tetrahedron letters》2007,48(51):9012-9014
Latoxanthin was isolated as a minor carotenoid from the ripe fruits of yellow tomato shaped paprika (Capsicum annuum var. lycopersiciforme flavum) and identified as (all-E,3S,5R,6R,3′S,5′R,6′S)-5′,6′-epoxy-5,6,5′,6′-tetrahydro-β,β-carotene-3,5,6,3′-tetrol based on spectral data. 相似文献
58.
Veronika Sobotíková Miloslav Feistauer 《Numerical Methods for Partial Differential Equations》2007,23(6):1368-1395
This paper is concerned with the effect of numerical integration applied to the discontinuous Galerkin finite element discretization of nonlinear convection‐diffusion problems in 2D. In the space semidiscretization the volume and line integrals are evaluated by numerical quadratures. Our goal is to estimate the error caused by the numerical integration and to show what numerical quadratures guarantee that the accuracy of the method with exact integration is preserved. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 相似文献
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60.
Next‐Generation o‐Nitrobenzyl Photolabile Groups for Light‐Directed Chemistry and Microarray Synthesis
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Nicole Kretschy Ann‐Katrin Holik Prof. Veronika Somoza Dr. Klaus‐Peter Stengele Prof. Mark M. Somoza 《Angewandte Chemie (International ed. in English)》2015,54(29):8555-8559
Light as an external trigger is a valuable and easily controllable tool for directing chemical reactions with high spatial and temporal accuracy. Two o‐nitrobenzyl derivatives, benzoyl‐ and thiophenyl‐NPPOC, undergo photo‐deprotection with significantly improved efficiency over that of the commonly used NPPOC group. The two‐ and twelvefold increase in photo‐deprotection efficiency was proven using photolithograph synthesis of microarrays. 相似文献