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1.
Functional Binding Surface of a β‐Hairpin VEGF Receptor Targeting Peptide Determined by NMR Spectroscopy in Living Cells
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![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Donatella Diana Anna Russomanno Dr. Lucia De Rosa Dr. Rossella Di Stasi Dr. Domenica Capasso Dr. Sonia Di Gaetano Dr. Alessandra Romanelli Dr. Luigi Russo Dr. Luca D. D'Andrea Prof. Roberto Fattorusso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):91-95
In this study, the functional interaction of HPLW peptide with VEGFR2 (Vascular Endothelial Growth Factor Receptor 2) was determined by using fast 15N‐edited NMR spectroscopic experiments. To this aim, 15N uniformly labelled HPLW has been added to Porcine Aortic Endothelial Cells. The acquisition of isotope‐edited NMR spectroscopic experiments, including 15N relaxation measurements, allowed a precise characterization of the in‐cell HPLW epitope recognized by VEGFR2. 相似文献
2.
Rossella Bartolo Anna Germinario Miguel Sánchez 《Annals of Global Analysis and Geometry》2002,21(1):63-84
In this paper the problem of the geodesic connectedness and convexity ofincomplete Riemannian manifolds is analyzed. To this aim, a detailedstudy of the notion of convexity for the associated Cauchy boundary iscarried out. In particular, under widely discussed hypotheses,we prove the convexity of open domains (whose boundaries may benondifferentiable) of a complete Riemannian manifold. Variationalmethods are mainly used. Examples and applications are provided,including a result for dynamical systems on the existence oftrajectories with fixed energy. 相似文献
3.
Rossella Agliardi 《Annali dell'Universita di Ferrara》1993,39(1):93-109
A well-known example by Ivrii concerning the operatorP=D
t
2
−t2lD
x
2
+atkDx (a≠0), shows that there exists a delicate relation amongl, k and the Gevrey index of well-posedness of the Cauchy problem. In this paper we give a generalization to a class of pseudo-differential
operators includingP.
Sunto Un famoso esempio di Ivrii riguardante l'operatoreP=D t 2 −t2lD x 2 +atkDx (a≠0), mostra che c'è una relazione sottile tral, k e l'indice di Gevrey di buona positura del problema di Cauchy. In questo articolo viene data una generalizzazione ad una classe di operatori pseudodifferenziali che comprendeP.相似文献
4.
González-Núñez ME Mello R Royo J Asensio G Monzó I Tomás F López JG Ortiz FL 《The Journal of organic chemistry》2005,70(9):3450-3457
[reaction: see text] Data on the apparent dipole moment of thianthrene-5-oxide (1) and (1)H NMR spectra in different solvents support the conformational mobility of 1, which flaps between two limit boat conformations with the sulfinyl group in pseudoequatorial and pseudoaxial positions, respectively. The conformational equilibrium of 1 occurs too fast for the (1)H NMR (500 MHz) time-scale even at -130 degrees C, and the equilibrium constant has not been determined. The apparent dipole moments of 1 in n-hexane and 1,4-dioxane and the (1)H NMR spectra of 1 and the model compounds cis- and trans-thianthrene-5,10-dioxides (2) and thianthrene (5) in different solvents and at various temperatures confirm that the relative position of the conformational equilibrium of 1 is solvent-dependent, and more polar solvents favor the conformation with the sulfoxide group in the pseudoaxial position (1(')(ax)). Variable-temperature (1)H NMR spectra have established the interconversion barrier of trans-2 and confirmed that the conformational equilibrium of cis-2 is strongly displaced toward the conformation with both sulfinyl groups in the pseudoequatorial position. The (1)H NMR data support the transannular interaction of the functional groups in 1 and trans-2. 相似文献
5.
Baeyer-Villiger oxidation with potassium peroxomonosulfate supported on acidic silica gel 总被引:1,自引:0,他引:1
González-Núñez ME Mello R Olmos A Asensio G 《The Journal of organic chemistry》2005,70(26):10879-10882
[reaction: see text] Potassium peroxomonosulfate deposited onto silica SiO2 x KHSO5 efficiently reacts with ketones in dichloromethane at room temperature to give the corresponding esters or lactones in quantitative yields. This method avoids hydrolysis of the reaction products. The Baeyer-Villiger reaction is catalyzed by potassium hydrogensulfate present in the supported reagent. 相似文献
6.
7.
Lanthanide Identity Governs Guest-Induced Dimerization in LnIII[15-MC
N(L-pheHA)-5])3+ Metallacrowns
Prof. Carmelo Sgarlata Bernadette L. Schneider Valeria Zito Dr. Rossella Migliore Prof. Matteo Tegoni Prof. Vincent L. Pecoraro Prof. Giuseppe Arena 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17669-17675
Series of lanthanide-containing metallic coordination complexes are frequently presented as structurally analogous, due to the similar chemical and coordinative properties of the lanthanides. In the case of chiral (LnIII[15-MC N(L-pheHA)-5])3+ metallacrowns (MCs), which are well established supramolecular hosts, the formation of dimers templated by a dicarboxylate guest (muconate) in solution of neutral pH is herein shown to have a unique dependence on the identity of the MC's central lanthanide. Calorimetric data and nuclear magnetic resonance diffusion studies demonstrate that MCs containing larger or smaller lanthanides as the central metal only form monomeric host-guest complexes whereas analogues with intermediate lanthanides (for example, Eu, Gd, Dy) participate in formation of dimeric host-guest-host compartments. The driving force for the dimerization event across the series is thought to be a competition between formation of highly stable MCs (larger lanthanides) and optimally linked bridging guests (smaller lanthanides). 相似文献
8.
Lucia De Rosa Rossella Di Stasi Alessandra Romanelli Luca Domenico DAndrea 《Molecules (Basel, Switzerland)》2021,26(12)
Although a plethora of chemistries have been developed to selectively decorate protein molecules, novel strategies continue to be reported with the final aim of improving selectivity and mildness of the reaction conditions, preserve protein integrity, and fulfill all the increasing requirements of the modern applications of protein conjugates. The targeting of the protein N-terminal alpha-amine group appears a convenient solution to the issue, emerging as a useful and unique reactive site universally present in each protein molecule. Herein, we provide an updated overview of the methodologies developed until today to afford the selective modification of proteins through the targeting of the N-terminal alpha-amine. Chemical and enzymatic strategies enabling the selective labeling of the protein N-terminal alpha-amine group are described. 相似文献
9.
Francesca Sisto Simone Carradori Paolo Guglielmi Mattia Spano Daniela Secci Arianna Granese Anatoly P. Sobolev Rossella Grande Cristina Campestre Maria Carmela Di Marcantonio Gabriella Mincione 《Molecules (Basel, Switzerland)》2021,26(7)
Following a similar approach on carvacrol-based derivatives, we investigated the synthesis and the microbiological screening against eight strains of H. pylori, and the cytotoxic activity against human gastric adenocarcinoma (AGS) cells of a new series of ether compounds based on the structure of thymol. Structural analysis comprehended elemental analysis and 1H/13C/19F NMR spectra. The analysis of structure–activity relationships within this molecular library of 38 structurally-related compounds reported that some chemical modifications of the OH group of thymol led to broad-spectrum growth inhibition on all isolates. Preferred substitutions were benzyl groups compared to alkyl chains, and the specific presence of functional groups at para position of the benzyl moiety such as 4-CN and 4-Ph endowed the most anti-H. pylori activity toward all the strains with minimum inhibitory concentration (MIC) values up to 4 µg/mL. Poly-substitution on the benzyl ring was not essential. Moreover, several compounds characterized by the lowest minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) values against H. pylori were also tested in order to verify a cytotoxic effect against AGS cells with respect to 5-fluorouracil and carvacrol. Three derivatives can be considered as new lead compounds alternative to current therapy to manage H. pylori infection, preventing the occurrence of severe gastric diseases. The present work confirms the possibility to use natural compounds as templates for the medicinal semi-synthesis. 相似文献
10.
Cell Tracking with Caged Xenon: Using Cryptophanes as MRI Reporters upon Cellular Internalization
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Stefan Klippel Jörg Döpfert Dr. Jabadurai Jayapaul Martin Kunth Federica Rossella Matthias Schnurr Dr. Christopher Witte Dr. Christian Freund Dr. Leif Schröder 《Angewandte Chemie (International ed. in English)》2014,53(2):493-496
Caged xenon has great potential in overcoming sensitivity limitations for solution‐state NMR detection of dilute molecules. However, no application of such a system as a magnetic resonance imaging (MRI) contrast agent has yet been performed with live cells. We demonstrate MRI localization of cells labeled with caged xenon in a packed‐bed bioreactor working under perfusion with hyperpolarized‐xenon‐saturated medium. Xenon hosts enable NMR/MRI experiments with switchable contrast and selectivity for cell‐associated versus unbound cages. We present MR images with 103‐fold sensitivity enhancement for cell‐internalized, dual‐mode (fluorescence/MRI) xenon hosts at low micromolar concentrations. Our results illustrate the capability of functionalized xenon to act as a highly sensitive cell tracer for MRI detection even without signal averaging. The method will bridge the challenging gap for translation to in vivo studies for the optimization of targeted biosensors and their multiplexing applications. 相似文献