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91.
Alberto de Juan Dr. Yann Pouillon Dr. Luisa Ruiz‐González Dr. Almudena Torres‐Pardo Dr. Santiago Casado Prof. Dr. Nazario Martín Prof. Dr. Ángel Rubio Dr. Emilio M. Pérez 《Angewandte Chemie (International ed. in English)》2014,53(21):5394-5400
Extensive research has been devoted to the chemical manipulation of carbon nanotubes. The attachment of molecular fragments through covalent‐bond formation produces kinetically stable products, but implies the saturation of some of the C? C double bonds of the nanotubes. Supramolecular modification maintains the structure of the SWNTs but yields labile species. Herein, we present a strategy for the synthesis of mechanically interlocked derivatives of SWNTs (MINTs). In the key rotaxane‐forming step, we employed macrocycle precursors equipped with two π‐extended tetrathiafulvalene SWNT recognition units and terminated with bisalkenes that were closed around the nanotubes through ring‐closing metathesis (RCM). The mechanically interlocked nature of the derivatives was probed by analytical, spectroscopic, and microscopic techniques, as well as by appropriate control experiments. Individual macrocycles were observed by HR STEM to circumscribe the nanotubes. 相似文献
92.
Susana Araceli Carrizales Álvarez Anna Ilyina Karla Monzerratt Gregorio Jáuregui José Luis Martínez Hernández Brenda Berenice Vazquez Gutiérrez Elda Patricia Segura Ceniceros Alejandro Zugasti Cruz Hened Saade Caballero Raúl Guillermo López Campos 《Applied biochemistry and biotechnology》2014,174(5):1945-1958
Avian influenza viruses preferentially bind to sialic acid alpha-2,3-galactose (N-SA-α-2,3-Gal) receptors on epithelial cells. Herein, we describe a procedure we have developed for isolation of N-SA-α-2,3-Gal receptors from porcine trachea using magnetic nanoparticles (NPs) coated with chitosan (NP-Ch) and functionalized with Maackia amurensis lectin (NP-lectin). Magnetic nanoparticles were coated with chitosan in a one-step co-precipitation, and then M. amurensis lectin was immobilized covalently using glutaraldehyde. Lectin coated nanoparticles were incubated with sialic acid enriched fraction of tracheal homogenate, and N-SA-α-2,3-Gal receptor was extracted under magnetic field in two cycles. The presence of 66.4 kDa protein was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The interaction of immobilized receptor (NP-Ch-R) with M. amurensis lectin (NP-Ch-R-L) was demonstrated by Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA). 相似文献
93.
Álvaro Dávila García Sylvain Bernès Fernando Sartillo-Piscil Rosa Luisa Meza-León 《Journal of heterocyclic chemistry》2020,57(12):4373-4379
The enantiopure synthesis of a truncated tetradenolide is presented. Starting from the versatile Chiron 7,3-lactone-xylofuranose derivative (7,3-LXF), the enantiomerically pure synthesis of the title compound is obtained in six steps with a 40% overall yield. 相似文献
94.
Dr. Luis Martín-Gomis Sairaman Seetharaman David Herrero Prof. Dr. Paul A. Karr Prof. Dr. Fernando Fernández-Lázaro Prof. Dr. Francis D'Souza Prof. Dr. Ángela Sastre-Santos 《Chemphyschem》2020,21(20):2254-2262
The effect of donor-acceptor distance in controlling the rate of electron transfer in axially linked silicon phthalocyanine-C60 dyads has been investigated. For this, two C60-SiPc-C60 dyads, 1 and 2 , varying in their donor-acceptor distance, have been newly synthesized and characterized. In the case of C60-SiPc-C60 1 where the SiPc and C60 are separated by a phenyl spacer, faster electron transfer was observed with kcs equal to 2.7×109 s−1 in benzonitrile. However, in the case of C60-SiPc-C60 2 , where SiPc and C60 are separated by a biphenyl spacer, a slower electron transfer rate constant, kcs=9.1×108 s−1, was recorded. The addition of an extra phenyl spacer in 2 increased the donor-acceptor distance by ∼4.3 Å, and consequently, slowed down the electron transfer rate constant by a factor of ∼3.7. The charge separated state lasted over 3 ns, monitoring time window of our femtosecond transient spectrometer. Complimentary nanosecond transient absorption studies revealed formation of 3SiPc* as the end product and suggested the final lifetime of the charge separated state to be in the 3–20 ns range. Energy level diagrams established to comprehend these mechanistic details indicated that the comparatively high-energy SiPc.+-C60.− charge separated states (1.57 eV) populated the low-lying 3SiPc* (1.26 eV) prior returning to the ground state. 相似文献
95.
Víctor Yañez Rodríguez Miguel Ángel del Águila María José Iglesias Fernando López Ortiz 《Tetrahedron》2012,68(36):7355-7362
Directed ortho lithiation of diphenylphosphinic acid and subsequent electrophilic trapping provides mono ortho-functionalized derivatives including enantiopure γ-aminophosphinic acids in moderate yields. Copper catalyzed coupling of the ortho anion leads to biphenyl-2,2′-diylbis(phenylphosphinic acid), a phosphorus analogue of biphenyl-2,2′-dicarboxylic acid. Preliminary studies of the metal-binding abilities of this O,O-chelating ligand towards a series of metal cations are included. 相似文献
96.
97.
María Yolanda Ríos M. Ángeles Ramírez‐Cisneros Ismael León‐Rivera Samuel Estrada‐Soto Gabriel Navarrete‐Vázquez A. Berenice Aguilar‐Guadarrama 《Magnetic resonance in chemistry : MRC》2012,50(4):329-331
Complete 1H and 13C NMR chemical shift assignments for 3,4‐seco‐lup‐20(29)‐en‐3‐oic acid ( 1 ) have been established by means of two‐dimensional COSY, HSQC, HMBC and NOESY spectroscopic experiments as well as by analysis of MS data. Compound 1 was isolated from Decatropis bicolor (Zucc.) Radlk. (Rutaceae) in addition to six coumarins and one alkaloid of known structure. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
98.
Dendronized Anionic Gold Nanoparticles: Synthesis,Characterization, and Antiviral Activity
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Cornelia E. Peña‐González Pilar García‐Broncano Prof. M. Francesca Ottaviani Dr. Michela Cangiotti Dr. Alberto Fattori Margarita Hierro‐Oliva Prof. M. Luisa González‐Martín Dr. Jorge Pérez‐Serrano Dr. Rafael Gómez Prof. M. Ángeles Muñoz‐Fernández Dr. Javier Sánchez‐Nieves Dr. F. Javier de la Mata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2987-2999
Anionic carbosilane dendrons decorated with sulfonate functions and one thiol moiety at the focal point have been used to synthesize water‐soluble gold nanoparticles (AuNPs) through the direct reaction of dendrons, gold precursor, and reducing agent in water, and also through a place‐exchange reaction. These nanoparticles have been characterized by NMR spectroscopy, TEM, thermogravimetric analysis, X‐ray photoelectron spectroscopy (XPS), UV/Vis spectroscopy, elemental analysis, and zeta‐potential measurements. The interacting ability of the anionic sulfonate functions was investigated by EPR spectroscopy with copper(II) as a probe. Different structures and conformations of the AuNPs modulate the availability of sulfonate and thiol groups for complexation by copper(II). Toxicity assays of AuNPs showed that those produced through direct reaction were less toxic than those obtained by ligand exchange. Inhibition of HIV‐1 infection was higher in the case of dendronized AuNPs than in dendrons. 相似文献
99.
Efrén Andablo-Reyes Roque Hidalgo-Álvarez Juan de Vicente 《ournal of non Newtonian Fluid Mechanics》2010,165(19-20):1419-1421
This communication describes a general procedure for the estimation of the true gap and tilt angle in commercially available torsional flow plate–plate rheometers by simply measuring the torque and normal force acting on the plates when shearing a Newtonian fluid. 相似文献
100.
Arturo Álvarez Vázquez 《Archiv der Mathematik》2010,95(1):25-29
In this paper we present a calculation to study a relationship between the generalized theta function and the Deuring polynomial. 相似文献