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81.
Aliakbar Dehno Khalaji Mahsa Nikookar Catherine Charles Smail Triki Franck Thetiot Debasis Das 《Journal of Cluster Science》2014,25(2):605-615
A novel bidentate Schiff base ligand L (L = N-(4-amino-2-chloro-phenyl)-2-hydroxybenzaldehyde) and the subsequent octahedral manganese(III) Schiff base complex MnL 3 have been synthesized and characterized by, FT-IR spectroscopy and elemental analyses (CHN). Additionally, Schiff base ligand has been characterized by 1H NMR spectroscopy. Thermogravimetric analysis of the ligand and its metal complexes reveals their thermal stability and decomposition pattern. Thus, the MnL 3 complex has been investigated as a novel precursor for the facile preparation of Mn3O4 nanoparticles via solid-state thermal decomposition under aerobic conditions, at a temperature of ca. 450 °C The resulting Mn3O4 nanocrystals were characterized by FT-IR spectroscopy, X-ray powder diffraction (XRPD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The XRPD studies reveal the characteristic diffraction peaks indexed to the Mn3O4 hausmanite structure, while the absence of additional peaks tends to clearly indicate the high purity of the sample. In addition, the TEM/SEM investigations displayed the nanoplate shape of the rather monodisperse crystalline Mn3O4 nanoparticles, with an average diameter of ca. 10 nm. The statistical distribution of the nanoparticles size has to be provided with an histogram graphic. 相似文献
82.
Paulina X. Medina Rangel Elena Moroni Franck Merlier Prof. Levi A. Gheber Prof. Razi Vago Dr. Bernadette Tse Sum Bui Prof. Karsten Haupt 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(7):2838-2844
One of the most promising strategies to treat cancer is the use of therapeutic antibodies that disrupt cell–cell adhesion mediated by dysregulated cadherins. The principal site where cell–cell adhesion occurs encompasses Trp2 found at the N-terminal region of the protein. Herein, we employed the naturally exposed highly conserved peptide Asp1-Trp2-Val3-Ile4-Pro5-Pro6-Ile7, as epitope to prepare molecularly imprinted polymer nanoparticles (MIP-NPs) to recognize cadherins. Since MIP-NPs target the site responsible for adhesion, they were more potent than commercially available therapeutic antibodies for inhibiting cell–cell adhesion in cell aggregation assays, and for completely disrupting three-dimensional tumor spheroids as well as inhibiting invasion of HeLa cells. These biocompatible supramolecular anti-adhesives may potentially be used as immunotherapeutic or sensitizing agents to enhance antitumor effects of chemotherapy. 相似文献
83.
Ashraf A. Aly Stefan Brse Alaa A. Hassan Nasr K. Mohamed Lamiaa E. Abd El-Haleem Martin Nieger Nesrin M. Morsy Mohammed B. Alshammari Mahmoud A. A. Ibrahim Elshimaa M. N. Abdelhafez 《Molecules (Basel, Switzerland)》2020,25(23)
Three new series of paracyclophanyl-dihydronaphtho[2,3-d]thiazoles and paracyclophanyl-thiazolium bromides were designed, synthesized, and characterized by their spectroscopic data, along with X-ray analysis. One-dose assay results of anticancer activity indicated that 3a–e had the highest ability to inhibit the proliferation of different cancer cell lines. Moreover, the hybrids 3c–e were selected for five-dose analyses to demonstrate a broad spectrum of antitumor activity without apparent selectivity. Interestingly, series I compounds (Z)-N-substituted-4,9-dihydronaphtho[2,3-d]thiazol-3(2H)-yl)-4′-[2.2]paracyclophanylamide) that are carrying 1,4-dihydronaphthoquinone were more active as antiproliferative agents than their naphthalene-containing congeners (series II: substituted 2-(4′-[2.2]paracyclophanyl)hydrazinyl)-4-(naphth-2-yl)-thiazol-3-ium bromide hybrids) and (series III: 3-(4′-[2.2]paracyclophanyl)amido-2-(cyclopropylamino)-4-(naphth-2-yl)thiazol-3-ium bromide) toward the SK-MEL-5 melanoma cell line. Further antiproliferation investigations of 3c and 3e on the healthy, normal unaffected SK-MEL-5 cell line indicated their relative safety. Compound 3c showed an inhibition of eight isoforms of cyclin-dependent kinases (CDK); however, it exhibited the lowest IC50 of 54.8 nM on CDK1 in comparison to Dinaciclib as a reference. Additionally, compound 3c revealed a remarkable downregulation of phospho-Tyr15 with a level (7.45 pg/mL) close to the reference. 3c mainly showed cell cycle arrest in the pre-G1 and G2/M phases upon analysis of the SK-MEL-5 cell line. The sequential caspase-3 assay for 3c indicated a remarkable overexpression level. Finally, a molecular docking study was adopted to elucidate the binding mode and interactions of the target compounds with CDK1. 相似文献
84.
The Sasa-satsuma(SS) dynamical equation interpret propagation of ultra-short and femto-second pulses in optical fibers. This dynamical model has important physical significance.In this article, two mathematical techniques namely, improved F-expansion and improved auxiliary methods are utilized to construct the several types of solitons such as dark soliton, bright soliton, periodic soliton, Elliptic function and solitary waves solutions of Sasa-satsuma dynamical equation. These results have imperative applications in sciences and other fields, and constructive to recognize the physical structure of this complex dynamical model. The computing work and obtained results show the influence and effectiveness of current methods. 相似文献
85.
86.
Dr. Tao Liu Dr. Aline Nonat Dr. Maryline Beyler Dr. Martín Regueiro‐Figueroa Dr. Katia Nchimi Nono Dr. Olivier Jeannin Dr. Franck Camerel Dr. François Debaene Dr. Sarah Cianférani‐Sanglier Prof. Raphaël Tripier Dr. Carlos Platas‐Iglesias Dr. Loïc J. Charbonnière 《Angewandte Chemie (International ed. in English)》2014,53(28):7259-7263
Lanthanide complexes (Ln=Eu, Tb, and Yb) that are based on a C2‐symmetric cyclen scaffold were prepared and characterized. The addition of fluoride anions to aqueous solutions of the complexes resulted in the formation of dinuclear supramolecular compounds in which the anion is confined into the cavity that is formed by the two complexes. The supramolecular assembly process was monitored by UV/Vis absorption, luminescence, and NMR spectroscopy and high‐resolution mass spectrometry. The X‐ray crystal structure of the europium dimer revealed that the architecture of the scaffold is stabilized by synergistic effects of the Eu? F? Eu bridging motive, π stacking interactions, and a four‐component hydrogen‐bonding network, which control the assembly of the two [EuL] entities around the fluoride ion. The strong association in water allowed for the luminescence sensing of fluoride down to a detection limit of 24 nM . 相似文献
87.
David E. Salazar Marcano Mhamad Aly Moussawi Alexander V. Anyushin Sarah Lentink Luc Van Meervelt Ivana Ivanovi-Burmazovi Tatjana N. Parac-Vogt 《Chemical science》2022,13(10):2891
Hybrid structures incorporating different organic and inorganic constituents are emerging as a very promising class of materials since they synergistically combine the complementary and diverse properties of the individual components. Hybrid materials based on polyoxometalate clusters (POMs) are particularly interesting due to their versatile catalytic, redox, electronic, and magnetic properties, yet the controlled incorporation of different clusters into a hybrid structure is challenging and has been scarcely reported. Herein we propose a novel and general strategy for combining multiple types of metal-oxo clusters in a single hybrid molecule. Two novel hybrid POM structures (HPOMs) bis-functionalised with dipentaerythritol (R–POM1–R; R = (OCH2)3CCH2OCH2C(CH2OH)) were synthesised as building-blocks for the formation of heterometallic hybrid triads (POM2–R–POM1–R–POM2). Such a modular approach resulted in the formation of four novel heterometallic hybrids combing the Lindqvist {V6}, Anderson–Evans {XMo6} (X = Cr or Al) and trisubstituted Wells–Dawson {P2V3W15} POM structures. Their formation was confirmed by multinuclear Nuclear Magnetic Resonance (NMR), infrared (IR) and UV-Vis spectroscopy, as well as Mass Spectrometry, Diffusion Ordered Spectroscopy (DOSY) and elemental analysis. The thermal stability of the hybrids was also examined by Thermogravimetric Analysis (TGA), which showed that the HPOM triads exhibit higher thermal stability than comparable hybrid structures containing only one type of POM. The one-pot synthesis of these novel compounds was achieved in high yields in aqueous and organic media under simple reflux conditions, without the need of any additives, and could be translated to create other hybrid materials based on a variety of metal-oxo cluster building-blocks.A versatile modular approach has been developed for incorporating different metal-oxo nanoclusters with characteristic structures into a single hybrid molecule by covalently linking them with polyol ligands. 相似文献
88.
89.
Alaa A. Hassan Yusria R. Ibrahim Essmat M. El‐Sheref Ashraf A. Aly Stefan Bräse Alan B. Brown 《Journal of heterocyclic chemistry》2012,49(6):1380-1385
1‐Substituted 3‐[3‐(methyl/phenyl)‐1H‐pyrazol‐5‐yl]thioureas react with the triple bond of dimethyl acetylenedicarboxylate forming (Z)‐methyl 2‐[(Z)‐3‐substituted‐2‐(3‐(methyl/phenyl‐1H‐pyrazol‐5‐ylimino)‐4‐oxothiazolidin‐5‐ylidene)acetates. Rational for these conversations are presented. 相似文献
90.