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1.
《印度化学会志》2022,99(11):100754
Naked-eye colored chemo dosimeter based on vanilline based conjugated sensor was synthesized and characterized. The main point of this paper is that the solvent also affects on selectivity of metals. Vanilline based conjugate sensor exhibited high selectivity and sensitivity for detection of Ferric ions (Fe+3) in all (both polar and nonpolar) solvents according to absorbance which can be observed by naked eye. The selectivity was more prominent in nonpolar or less polar solvent due to solubility factor of ions and sensor but not for polar. The detection of limit of the synthesized probes was shown up to 0.84 ppm. The dielectric constant of solvents affected on the complex formation of ligand with transition metal ions. A filter paper strip system was used for rapid monitoring of detection by color variation. 相似文献
2.
Federica Valentini Giulia Brufani Benedetta Di Erasmo Luigi Vaccaro 《Current Opinion in Green and Sustainable Chemistry》2022
The great challenge for modern research is to define the most efficient tools to make more sustainable the industrial production and manufacturing. Among the different aspects that require attention the replacement of toxic and/or non-renewable solvents it is certainly playing a crucial role. Dealing with widely used dipolar aprotic solvents, among the different alternatives proposed in the literature γ-valerolactone (GVL) plays a pivotal role covering different application area. In this contribution, the benefits derived from the use of GVL as a circular, safe, biomass-derived reaction medium are highlighted covering most recent publications (2021). The presentation has been divided into three major sections: (i) biomass valorization, (ii) materials synthesis, manufacturing and recycle and (iii) new synthetic methodologies. 相似文献
3.
《Arabian Journal of Chemistry》2022,15(10):104145
In the present study, novel representatives of the important group of biologically-active, dehydroabietic acid-bearing dithiocarbamate moiety, were synthesized and characterized by 1H NMR, 13C NMR, HR-MS. The in vitro antiproliferative activity evaluation (MTT) indicated that these compounds exhibited potent inhibitory activities in various cancer cell lines (HepG-2, MCF-7, HeLa, T-24, MGC-803). Particularly, compound III-b possessed extraordinary cytotoxicity with low micromolar IC50 values ranging from 4.07 to 38.84 µM against tested cancer cell lines, while displayed weak cytotoxicity on two normal cell lines (LO-2 and HEK 293 T). Subsequently, the potential mechanisms of representative compound III-b were elementarily investigated by Transwell experiment, which showed III-b can inhibit cancer cells migration. Annexin-V/PI dual staining showed that the compound can induce HepG-2 cells apoptosis in a dose-dependent manner. Meanwhile this apoptosis may be related to the upregulated protein expression of cleaved-caspase 3, cleaved-caspase 9, Bax and downregulated of Bcl-2 indicated by Western Blot. Later study further confirmed that ROS levels in HepG-2 cells increased significantly with the rise of concentrations. In addition, through the network pharmacology data analyzing, the core targets and signaling pathways of compound III-b for treatment of liver neoplasms were forecasted. Molecular docking model showed that compound III-b had high affinity with hub targets (CASP3, EGFR, HSP90AA1, MAPK1, ERBB2, MDM2), suggesting that compound III-b might target the hub protein to modulate signaling activity. Taken together, these data indicated that dehydroabietic acid structural modification following the “Molecular hybridization” principle is a feasible way to discover the potential multi-targeted antitumor compounds. 相似文献
4.
《中国化学快报》2019,30(11):1951-1954
Utilization of intermolecular Friedel-Crafts and intramolecular condensation reaction,novel 1,3-di-(pyridine-2-yl)benzene(N,C,N terdentate) skeleton with electro-withdrawing group in 6' position of pyridyl and a cyclization between 6' position of pyridyl and 6 position of benzyl ring were firstly designed and synthesized.The structures of these novel N,C,N terdentate were confirmed by NMR,MS and X-ray single crystalanalyses.The photophysical properties of these compounds were briefly explored. 相似文献
5.
6.
The past decades have witnessed the emergence of low-dimensional carbon-based nanostructures owing to their unique properties and various subsequent applications. It is of fundamental importance to explore ways to achieve atomically precise fabrication of these interesting structures. The newly developed on-surface synthesis approach provides an efficient strategy for this challenging issue, demonstrating the potential of atomically precise preparation of low-dimensional nanostructures. Up to now, the formation of various surface nanostructures, especially carbon-based ones, such as graphene nanoribbons (GNRs), kinds of organic (organometallic) chains and films, have been achieved via on-surface synthesis strategy, in which in-depth understanding of the reaction mechanism has also been explored. This review article will provide a general overview on the formation of one-dimensional carbon-based nanostructures via on-surface synthesis method. In this review, only a part of the on-surface chemical reactions (specifically, C−X (X=Cl, Br, I) and C−H activation reactions) under ultra-high vacuum conditions will be covered. 相似文献
7.
《Tetrahedron letters》2019,60(44):151205
A simple and efficient approach for the synthesis of novel 2-carboxanilido-3-arylquinazolin-4-ones via the one-pot condensation of readily available N1-(2-carboxyphenyl)-N2-(aryl)oxalamides with various aromatic amines is described. Notably, this methodology allows us to synthesize 3-aryl-quinazolin-4-ones using aromatic amines with various substituents, both electron-donating and electron-withdrawing, which ensures structural diversity of the products and an atomic-economic process. 相似文献
8.
《中国化学快报》2020,31(12):3209-3212
Constructing a reliable and favorable electrode-electrolyte interface is crucial to utilize the exceptional energy storage capability in commercial lithium-ion batteries. Here, we report a facile synthesis approach for the lithium difluorophosphate (LiPO2F2) solution as an effective film-forming additive via direct adding the Li2CO3 into LiPF6 solution at 45 °C. Benefiting from the significantly reduced interface resistance (RSEI) and charge transfer impedance (Rct) of both the cathode and anode by adding the prepared LiPO2F2 solution into a baseline electrolyte, the cycling performance of the graphite||LiNi0.5Mn0.3Co0.2O2 pouch cell is remarkably improved under all-climate condition. 相似文献
9.
The chalcogenido indates K6In2Q6 (Q = S, Se, Te) were synthesized from melts of the pure elements at a maximum temperature of 700 °C. All three potassium salts contain dinuclear units [In2Q6]6– of two edge-sharing [InQ4] tetrahedra. The sulfido and the selenido indate are isotypic and crystallize in the K6Mn2O6-type structure [monoclinic, space group P21/c, a = 784.32(9)/809.32(3), b = 1274.58(14)/1322.37(4), c = 836.48(9)/870.53(3) pm, β = 97.900(2)/97.5877(8)°, Z = 2, R1 = 0.0123/0.0109; for Q = S/Se]. The tellurido indate K6In2Te6 crystallizes in a new orthorhombic structure type [space group Pnma, a = 1793.70(12), b = 1491.55(11), c = 837.40(6) pm, Z = 4, R1 = 0.0157]. In this structure, the telluride anions form a hexagonal close packing, in which K+ cations occupy all octahedral voids; the In3+ ions take 1/6 (but always adjacent) tetrahedral voids. This structure-chemical relation to the h.c.p. packing, which is similarly found for most of the sodium dimetallates (e.g. Na6Fe2S6), is substantiated by a full crystallographic group-subgroup tree. The crystal chemistry of the new indates is discussed and compared with that of alkali chalcogenido metallates(III) of Fe, Al and Ga containing [M2Q6]6– dimers, which overall form as many as ten different structure types. DFT band structure calculations of the three title compounds exhibit bandgaps, which continuously decrease from the S to the Te compound and which are also in accordance with the pale yellow (S), bright yellow (Se) and red-brown (Te) color of the compounds. The chemical bonding in the salts and within the metallate anion is discussed on the basis of the partial DOS and a Bader analysis of the calculated electron density. 相似文献
10.
Myung Jun Kim Mutya A. Cruz Feichen Yang Benjamin J. Wiley 《Current Opinion in Electrochemistry》2019
Scalable, solution-phase syntheses of metal nanowires are enabling their increased use in electrochemical processes. This review highlights recent results demonstrating how metal nanowires can exhibit better durability and higher activity than traditional metal nanoparticle electrocatalysts on carbon supports. Metal nanowires can also form interconnected two-dimensional and three-dimensional (3D) networks that eliminate the need for a carbon support, thus eliminating the detrimental effects of carbon corrosion. Porous 3D networks of nanowires can be used as flow-through electrodes with the highest specific surface areas and mass transport coefficients obtained to date, enabling dramatic increases in the productivity of electrochemical reactions. Nanowire networks are also serving as 3D current collectors that improve the capacity of batteries. The tunable surface structure and dimensions of metal nanowires offer researchers a new opportunity to create electrodes that are tailored from the atomic scale to the microscale to improve electrochemical performance. 相似文献