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81.
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The crystal structure of NaSbF4 has been redetermined by X-ray diffraction. The coordination about antimony is AX6E with a 2.2.2.1 geometry. The units are linked by fluorine bridges and form a double layer perpendicular to the a axis. Infrared and Raman spectra were recorded and are discussed in terms of the distorted octahedral arrangement of fluorines about each antimony. 相似文献
83.
An efficient and facile one-pot synthesis is described for the preparation of novel tricyclic fused pyranothiazolopyrimidines containing both biologically active thiazolopyrimidine and pyranopyrimidine templates via three-component reaction involving an isocyanide with a dialkylacetylenedicarboxylate (DAAD) and 2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyrimidine-5,7(6H)-dione, in high yields. 相似文献
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Alkylidene Meldrum's acids and 2,6‐dimethylphenyl isocyanide react smoothly in the presence of arylhydroxylamines at room temperature to produce 2,5‐dioxo‐pyrrolidines in fairly high yield. 相似文献
86.
Nona Habibi Mahmoud Ebrahimi 《International journal of environmental analytical chemistry》2013,93(14):1459-1470
ABSTRACTA novel ion-selective electrochemical sensor based on kryptofix-22DD (1,10-didecyl-1,10-diaza-18-crown-6) as an ionophore was constructed for determination of lanthanum(III) cation in solutions. The D-Optimal Mixture Design(D-OMD) was used as an experimental design strategy for optimal formulation of the membrane ingredients, and the actual values of the ingredients were compared with their predicted values. The amounts of the ionophore, plasticizer, PVC, and also the graphite powder which influence the performance of the fabricated electrode were analyzed using D-OMD. A non-linear relationship was observed between the slope of the electrochemical response of the electrode and these variables and the interaction between the variables as well. The experimental results showed that the amount of the ionophore has the most positive effect on the electrochemical response of the electrode. The constructed electrode exhibits a Nernstian slope (20.60 ± 0.21 mv.decade?1) in a wide linear concentration range from 1.0 × 10?7 to 1.0 × 10?1 M with respect to La3+ cation at pH range of 4.0 to 6.0, and its detection limit was found to be:0.8 × 10?7M. The selectivity of the proposed electrode towards some of the metal cations present in lanthanum(III) cation solutions was tested, and the experimental results showed a good selectivity towards this metal cation. 相似文献
87.
Zohreh Mehri Lighvan Hossein Ali Khonakdar Abolfazl Heydari Mina Rafiee Maryam Dehdashti Jahromi Ali Derakhshani Amir Abbas Momtazi-Borojeni 《应用有机金属化学》2020,34(10):e5839
The organometallic palladium complex with nitrogen-containing heterocycles is a potent antitumor agent. Coordination of phosphorus ligands to organometallic complexes increases their hydrophilicity, promotes ligand−DNA interactions and damage level to cancer cells, and blocks division in target cells. In this study, a phosphaadamantane palladium complex ([Pd{(C,N)- (C12H8NH2)} (PTA) Cl], PTA = 1,3,5-Triaza-7-phosphaadamantane) ( 2 ) was synthesized via the reaction of biologically active PTA with binuclear palladacycles [Pd2{(C,N)-(C12H8NH2)}2(μ-Cl)2] ( 1 ). In vitro studies of the complex with DNA (calf-thymus) explored by UV–Vis, emission titration, circular dichroism and helix melting methods showed that the complex interacts with DNA via an intercalative mechanism. Furthermore, competitive binding studies using warfarin, digoxin and ibuprofen site markers containing definite binding sites revealed the binding of the complex to site I on bovine serum albumin. The in vitro release mechanism of the palladium complex exhibited a biphasic pattern characterized by an initial burst release followed by a slower sustained release. Ultimately, in vitro evaluation of cytotoxicity and cell death showed that the complexes were able to decrease the viability of human cancer cell lines (MCF-7 and Jurkat) in a dose-dependent manner, but lower decreases were observed in the viability of normal fibroblast cells ASF-4 at the dosages evaluated. Finally, the order of in vitro anticancer activities was found to be consistent with the DNA-binding affinities. 相似文献
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A simple and efficient method for the synthesis of 9,9‐dimethyl‐9,10‐dihydro‐8H‐benzo‐[α]xanthen‐11(12)‐one derivatives (DDBXs) was developed by the condensation reaction of various substituted aryl al... 相似文献
90.