Zobrazení zdroje stránky Pritchardcherry8884

However, contrary to the pale yellow coloration of the [Pt(CN)4]2-/HAT(CN)6 systems, currently the dark violet or dark green coloration of solutions and crystalline phases were noted owing to the intense absorption in almost the whole visible region. DFT calculations reproduced the UV-Vis spectroscopic characteristics and linked it with the enhanced charge-transfer of the [PtX4]2-HAT(CN)6 electronic interactions. Based on the isomorphism of all three (PPh4)2[PtL4][HAT(CN)6]·3MeCN congeners we constructed and characterized the unprecedented, first ever anion-π-based binary rod-like core-shell crystalline composites 1-X@1-CN.Correction for 'Single-precision open-shell CCSD and CCSD(T) calculations on graphics processing units' by Zhifan Wang et al., Phys. Chem. Chem. Phys., 2020, 22, 25103-25111, DOI .Repurposed drugs are now considered as attractive therapeutics against COVID-19. It is shown that Remdesivir, a nucleoside drug that was originally invented for the Ebola virus, is effective in suppressing the replication of SARS-CoV-2 that causes COVID-19. Similarly, Galidesivir, Favipiravir, Ribavirin, N4-hydroxycytidine (EIDD-1931), and EIDD-2801 (a prodrug of EIDD-1931) were also found to be effective against COVID-19. However, the mechanisms of action of these drugs are not yet fully understood. For example, in some experimental studies, these drugs were proposed to act as a RNA-chain terminator, while in other studies, these were proposed to induce base-pair mutations above the error catastrophe limit to stall the replication of the viral RNA. To understand the mutagenic effects of these drugs, the role of different tautomers in their base-pairing abilities is studied here in detail by employing a reliable dispersion-corrected density functional theoretic method. It is found that Remdesivir and Galidesiiviral properties of these drugs.A Cu-catalyzed O-alkylation of phenol derivatives using alkylsilyl peroxides as alkyl radical precursors is described. The reaction proceeds smoothly under mild reaction conditions and the use of two different ligands with a Cu catalyst provides a wide range of products. A mechanistic study suggested that the reaction proceeds via a radical mechanism.Noble metal nanoparticles (NPs) are ideal scaffolds for the fabrication of sensing devices because of their high surface-to-volume ratio combined with their unique optical and electrical properties which are extremely sensitive to changes in the environment. Such characteristics guarantee high sensitivity in sensing processes. Metal NPs can be decorated with ad hoc molecular building blocks which can act as receptors of specific analytes. By pursuing this strategy, and by taking full advantage of the specificity of supramolecular recognition events, highly selective sensing devices can be fabricated. Besides, noble metal NPs can also be a pivotal element for the fabrication of chemical nose/tongue sensors to target complex mixtures of analytes. This review highlights the most enlightening strategies developed during the last decade, towards the fabrication of chemical sensors with either optical or electrical readout combining high sensitivity and selectivity, along with fast response and full reversibility, with special attention to approaches that enable efficient environmental and health monitoring.A series of pentametallic "cubane-plus-dangler" complexes have been target synthesized. [https://www.selleckchem.com/products/arv471.html selleck inhibitor] Among them, the [Fe3Ni2] aggregate strongly resembled the native oxygen-evolving center by mimicking the "cubane-plus-dangler" skeleton, the aqua binding site, and the connectivity between the pendent ion and the parent cubane. Our synthetic strategy that uses tri-substituted methanol as the "cubane-generator" and carboxylate as the pendant ligand provides a feasible approach for accessing model compounds of biological catalyst systems.Four new ligand precursors (H2L1-H2L4), derived from the Mannich condensation of two amino acids (l-Val and l-Phe) and two 3,5-disubstituted phenols (t-Bu or Me), and the corresponding oxidovanadium(iv) (1-4) and copper(ii) (6-7) complexes are synthesized. Two other related compounds (H2L5 and H2L6), containing an additional 2-methyl-pyridine arm, and the corresponding VIVO (5) and CuII (8-9) complexes were also obtained. All metal complexes are monomeric in the solid state, having a solvent molecule or a chloride ion in the coordination sphere. The in vitro cytotoxic activity of all compounds is evaluated against cancer cells from different origins. The IC50 values at 72 h are in the range of 6-15 μM for HeLa cells, 4-17 μM for A-549 cells and &gt;25 μM for MDA-MB-231 cells, except for [VIVOL1(CH3OH)] (1) and [CuL6(H2O)] (9). With the exception of H2L6, overall, the metal complexes are more cytotoxic than the corresponding ligand precursors. Globally, the cellular viability data show that (i) the l-Phe derived compounds are more cytotoxic than the corresponding l-Val complexes; (ii) the presence of the bulkier t-Bu groups increases the cytotoxicity; (iii) the presence of a 2-methyl-pyridine arm increases considerably the cytotoxicity; and (iv) the CuII-complexes are more cytotoxic than the VIVO-compounds. Complexes [VIVOL3(CH3OH)] (3), [CuL3(H2O)] (7) and [CuL5(H2O)] (8) were further evaluated and their mechanism of action was determined to be apoptosis, evidenced by AnnexinV staining and the increase in caspase 3/7 activity. Compounds 3, 7 and 8 also exhibit DNA cleavage activity, involving the formation of reactive oxygen species and were able to induce genomic damage in cells as determined by COMET assay.Nanographenes (NGs) and graphene nanoribbons (GNRs) are unique connectors between the domains of 1D-conjugated polymers and 2D-graphenes. They can be synthesized with high precision by oxidative flattening processes from dendritic or branched 3D-polyphenylene precursors. Their size, shape and edge type enable not only accurate control of classical (opto)electronic properties, but also access to unprecedented high-spin structures and exotic quantum states. NGs and GNRs serve as active components of devices such as field-effect transistors and as ideal objects for nanoscience. This field of research includes their synthesis after the deposition of suitable monomers on surfaces. An additional advantage of this novel concept is in situ monitoring of the reactions by scanning tunnelling microscopy and electronic characterization of the products by scanning tunnelling spectroscopy.