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991.
Dr. Eduardo Ferreira Molina Natana Aparecida Martins de Jesus Serge Paofai Dr. Peter Hammer Dr. Maria Amela-Cortes Dr. Malo Robin Dr. Stephane Cordier Dr. Yann Molard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(67):15248-15251
Hybrid materials that combine diureasil matrices and octahedral molybdenum clusters have been synthesized to design lead-, cadmium- and rare-earth-free emitters for lighting or optoelectronic applications. This association leads to homogeneous and stable hybrids, for which the emission color can be tailored in the entire visible range, including white light; this is thanks to effective energy transfers from the host to the nanocluster. 相似文献
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Teh-Chang Chou Ju-Fang Cheng Atul R. Gholap Jim Jing-Kai Huang Jyun-Chang Chen Jing-Kai Huang Jui-Chang Tseng 《Tetrahedron》2019,75(48):130689
A general approach toward the synthesis of multi-functionalized diazapentacene derivatives 1, using 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene (TDCp, 2), a substituted benzene-1,2-diamine (ADA, 6), and a naphthalene-1,4-dione (BQ, 3) as the building units, is described. The synthesis basically entails three operations: (i) oxidation of the dichloroetheno-bridge in the Diels-Alder cycloadduct 4 of TDCp and 3, (ii) condensation of the 1,2-diketone 5 thus generated with an ADA to give quinoxaline-fused polycyclic compounds 7, followed by (iii) an one-pot, three-reaction process keyed upon the base- or acid-catalyzed aromatization-driven Grob-type fragmentation to produce quinoxaline ring-embedded diazapentaceneesters 1. The diazapentacene derivative 1a underwent the nucleophilic aromatic ipso-amination with primary and secondary amines to afford the amino-substituted derivatives 12, which tend to self-assemble in solid state driven by the cofacial π-stacking interactions, demonstrated by the crystal packing structures of 12a and 12f. 相似文献
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Accreditation and Quality Assurance - Validation (and in some extension verification) are concepts often applied to analytical procedures (or methods). The new edition of ISO/IEC 17025 clearly... 相似文献
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Sayma Adriana Rodriguez-Montelongo Jesus Gonzalez-Hernandez Abel Hurtado Macias Ana Sonia Silva-Ramirez Claudia G. Castillo Martin del Campo Jose Manuel Gutierrez-Hernandez Facundo Ruiz Omar Gonzalez-Ortega 《Journal of nanoparticle research》2018,20(11):311
Hollow gold nanoshells (HGN) with a diameter of 50–70 nm and tunable optical properties within the near-infrared region were synthesized from a substitution reaction using a sacrificial template, in which the morphological properties of the HGN were affected by the synthesis conditions. Using EDX line scan, the composition of the structure was determined to verify if the sacrificial template is completely consumed or residues remain after the chemical synthesis, obtaining that the final HGN structure contains about 11% of the remaining silver that showed no significant effect on the cell viability of a hNS1 cell line, but resulted as toxic on a C6 glioma cell line at high concentrations. The photothermal properties were evaluated using a NIR laser, which despite its low power showed the conversion of light into heat. This study was conducted to evaluate the potential of these nanostructures as therapeutic agents with an emphasis on toxicity. 相似文献
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Synthesis,characterization and assessment of the cytotoxic activity of Cu(II), Fe(III) and Mn(III) complexes of camphoric acid‐derived salen ligands 下载免费PDF全文
Dina Murtinho Zênis N. da Rocha Ana Salomé Pires Roberto P. Jiménez Ana Margarida Abrantes Mafalda Laranjo Ana Catarina Mamede João Eduardo Casalta‐Lopes Maria Filomena Botelho Alberto A. C. C. Pais Sandra C. C. Nunes Hugh D. Burrows Telma Costa M. Elisa Silva Serra 《应用有机金属化学》2015,29(7):425-432
Novel Cu(II), Fe(III) and Mn(III) salen‐type metal complexes from (1R,3S)‐N,N′‐bis[salicylidene]‐1,3‐diamino‐1,2,2‐trimethylcyclopentane were synthesized and screened for their in vitro cytotoxic activity against three human cancer cell lines: melanoma, colorectal and breast. In vitro experiments carried out with the three metal complexes show that the copper complex exhibits the highest cytotoxic activity towards all cell lines studied, presenting IC50 values of 3.32–6.71 μM. A significant improvement in the anti‐proliferative effect, by 20‐fold, is observed with this complex when compared with conventional chemotherapy. The relationship between structure, redox characteristics and biological activity in human cancer cell lines was evaluated for the most efficient Cu(II) complex and associated with theoretical calculations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
An expedient approach to enhance Mizoroki–Heck coupling reaction by infrared irradiation using palladacycle compounds 下载免费PDF全文
Fernando Ortega‐Jiménez Francisco X. Domínguez‐Villa Alfredo Rosas‐Sánchez Guillermo Penieres‐Carrillo José G. López‐Cortés M. Carmen Ortega‐Alfaro 《应用有机金属化学》2015,29(8):556-560
An alternative and environmentally friendly strategy to promote the Mizoroki–Heck cross‐coupling reaction by the use of infrared irradiation using palladacycles as precatalysts is reported. Coupling products are obtained in high yield and short reaction time. A comparison with the classical use of reflux conditions, and commercial sources of palladium complexes, shows the advantages of this new alternative for promoting coupling reactions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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