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32.
Elasasy M. E. A. Elnaggar D. H. Hafez N. A. Abdel Azab M. E. Amr A. E. Omran M. M. Mohamed A. M. 《Russian Journal of General Chemistry》2021,91(5):915-925
Russian Journal of General Chemistry - Some new fluoro-heterocyclic compounds containing thiazole and pyridine moities have been synthesized and studied for their antiproliferative activity.... 相似文献
33.
Dr. Anton A. Anisimov Dr. Fedor V. Drozdov Yulia S. Vysochinskaya Ekaterina O. Minyaylo Prof. Alexander S. Peregudov Prof. Fedor M. Dolgushin Dr. Olga I. Shchegolikhina Prof. Aziz M. Muzafarov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(50):11404-11407
This study presents the synthesis of organoboron derivatives of stereoregular 4-, 6-, and 12-unit phenylcyclosilsesquioxanes. All compounds obtained were isolated in good yields (70–80 %) and were fully characterized by 1H, 13C, 29Si, 11B NMR, IR spectroscopy, HRMS ESI, and elemental microanalysis. The structure of the key modifier, obtained for the first time, 4-(tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl) dimethylvinylsilane, was also confirmed by single-crystal XRD. 相似文献
34.
Isomotive dielectrophoresis (isoDEP) is a unique DEP geometrical configuration where the gradient of the field-squared () is constant. IsoDEP analyzes polarizable particles based on their magnitude and direction of translation. Particle translation is a function of the polarizability of both the particles and suspending medium, the particles’ size and shape, and the frequency of the electric field. However, other electrokinetics act on the particles simultaneously, including electrothermal hydrodynamics. Hence, to maximize the DEP force relative to over electrokinetic forces, design parameters such as microchannel geometry, fabrication materials, and applied electric field must be properly tuned. In this work, scaling law analyses were developed to derive design rules, relative to particle diameter, to reduce unwanted electrothermal hydrodynamics relative to DEP-induced particle translation. For a particle suspended in 10 mS/m media, if the channel width and height are below ten particle diameters, the electrothermal-driven flow is reduced by ∼500 times compared to a channel that is 250 particles diameters in width and height. Replacing glass with silicon as the device's underlying substrate for an insulative-based isoDEP reduces the electrothermal induced flow approximately 20 times less. 相似文献
35.
A novel Schiff base namely (E)-3-((2,6-dihydroxypyrimidin-4-ylimino)methyl)-4H-chromen-4-one and its Co (II), N (II)i, Cu (II) and Cd (II) complexes have been synthesized and proved by elemental analysis, molar conductance, thermal analysis (TGA), Inductive Coupled plasma (ICP), magnetic moment measurements, X-ray powder diffraction, IR, EI-mass,1H NMR, 13C NMR,UV–Vis. and ESR spectral studies. On the basis of these data, it is evident that the Schiff base acts as bidentate via oxygen atom of carbonyl group and azomethine nitrogen atom for Co (II) complex; monobasic bidentate ligand for Ni (II), Cu (II) and Cd (II) complexes via oxygen atom of hydroxyl group and nitrogen atom of pyrimidine ring. The results showed all complexes have octahedral geometry. The average particle size of the ligand and its complexes were found to be 1.010–0.343 nm. The pharmacological action (antioxidant, antimicrobial and anticancer) of the prepared compounds is studied. The antitumor activity of the ligand and its metal complexes is evaluated against human liver carcinoma (HEPG2) cell. The data displayed the Co (II) complexes strong cytotoxicity where IC50 values of Co (II) complex and 5-fluorouracil (stander drug) are 9.33 and 7.86 μg/ml respectively. The Co (II) and Cd (II) complexes have antibacterial activity more than ampicillin (stander drug). The interaction of the synthesized compounds with calf-thymus DNA (CT-DNA) has been performed via absorption spectra and viscosity technique. The DNA- binding constants have been determined. 相似文献
36.
Novel Schiff base ligand based on the condensation of 4,6-diacetyl resorcinol with 2-amino-4-methylthiazole in addition to its metal complexes with Cr (III), Mn (II), Fe (III), Co (II), Ni (II), Cu (II), Zn (II) and Cd (II) ions have been synthesized. The structure, electronic properties, and thermal behaviour of Schiff base and its metal complexes have been studied by elemental analysis, mass, 1H NMR, IR spectra, thermal analysis, and theoretically by density function theory. The ligand acted as mononegative bidentate (NO) ligand and all complexes showed octahedral geometry except Cu (II) showed tetrahedral geometry as indicated from the spectral and magnetic studies. The Cu (II), Zn (II) and Cd (II) complexes were non electrolytes while the rest of the complexes were electrolytes. The antibacterial plus anticancer activities of the parent Schiff base and its metal complexes were screened. In addition, the molecular docking study was performed to explore the possible ways for binding to Crystal Structure of Human Astrovirus capsid protein (5ibv) receptor. 相似文献
37.
The strategy of structurally integrating noble metal and metal oxides is expected to offer exceptional opportunities toward emerging functions of all. We report the creation of an efficient hetero-structured nanocatalyst consisting of Mn3O4 core, SiO2 shell impregnated with noble Ag nanoparticles. The triple nanocatalyst Mn3O4/Ag/SiO2 was synthesized by using a facile three-step approach to disperse Ag nanoparticles between the surfaces of functionalized Mn3O4 and SiO2. The physicochemical structural characterization was performed by XRD and FTIR. The surface morphologies were observed by SEM and TEM. The EDX measurements confirmed the composition of the composite. The nanocomposite has been used as a catalyst for the degradation of Direct blue 78 in the presence of sodium borohydride (NaBH4). It has a drastic catalytic effect as compared to Mn3O4/Ag and Mn3O4. The rate constant of Direct blue 78 reduction followed the order: Mn3O4/Ag/SiO2 (0.25166 min−1) > Mn3O4/Ag (0.07971 min−1) > Mn3O4 (0.00947 min−1). The effects of different reaction conditions of the catalytic reaction have been determined. The catalytic activity of the as- synthesized nanocomposite was examined for the binary dyes system by incorporation of an additional dye (Sunset yellow). Its influence on the degradation rate and efficiency of Direct blue 78 was investigated. The nanocatalyst exhibited excellent catalytic activity towards the complete degradation of both the Direct blue 78 and Sunset yellow. The degradation percentage for these dyes reached 99.33 and 94.68%, respectively. The recovery and reusability of the Mn3O4/Ag/SiO2 nanocomposite was studied in the reduction reaction of Direct blue 78. Five consecutive recovery reaction cycles were performed. They revealed high stability and constant efficiency of the catalyst for four cycles. 相似文献
38.
Basma H. Amin Mohamed I. Abou-Dobara Mostafa A. Diab Essam A. Gomaa Mohammed A. El-Mogazy Adel Z. El-Sonbati Mohamed S. EL-Ghareib Mostafa A. Hussien Hanaa M. Salama 《应用有机金属化学》2020,34(8):e5689
A novel series of mixed-ligand complexes of 5,5′-{(1E,1E′)-1,4-phenelynebis(diazene-2,1-diyl)}bis(quinolin-8-ol) (H2L1) as a primary ligand and 4-aminoantipyrine(L2) as a secondary ligand with Mn(II) ion were prepared using two general formulae: [Mn2(H2L1)2(L2)2X4].4Cl (X = OH2( 1 ), ONO2−( 2 ), Cl=nil; OAc( 3 ), Cl = nil) and [Mn2(H2L1)(L2)2(O2SO2)2]( 4 ). Free ligands and their complexes were characterized. Electronic absorption spectra of the mixed-ligand complexes indicate a distorted octahedral geometry around the central metal ion, and the anions X− are in the axial positions for all compounds. The ligands behave in a neutral bidentate manner, through nitrogen atoms and oxygen atoms of the carbonyl group (L2), whereas H2L1 coordinated through nitrogen and OH groups as a neutral bidentate ligand. All complexes do not contain coordinated water molecules, but complex ( 1 ) contains four water molecules. The water molecules are removed in a single step. The complexes exhibited magnetic susceptibility corresponding to five unpaired electrons. The antimicrobial activity of the Mn(II) mixed-ligand complexes ( 1–4 ) against two gram-positive bacteria, three local gram-negative bacteria, and three fungi species was tested. Mn(II) mixed-ligand complex ( 2 ) exhibited significant antibacterial activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas sp. Mixed-ligand complex ( 2 ) exhibited a high potential cytotoxicity against the growth of human lung cancer cells. 相似文献
39.
Ilyas Saad Alfosail Feras K. Bellaredj Mohamed L. F. Younis Mohammad I. 《Nonlinear dynamics》2019,95(3):2263-2274
Nonlinear Dynamics - We present an investigation of the dynamic behavior of an electrostatically actuated clamped–clamped microbeam, under the simultaneous excitation of primary and... 相似文献
40.
Fanny Danton Dr. Mohamed Othman Dr. Ata Martin Lawson Dr. Ján Moncol Dr. Alina Ghinet Prof. Benoît Rigo Prof. Adam Daïch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(24):6113-6118
An efficient domino transformation using a phenyliodine(III) diacetate (PIDA)/I2 combination towards Morin 1,4-thiazine compounds has been developed starting from N,S-acetals. The latter leads to “one-step” regioselective methylene insertion without the need for traditional sulfoxide intermediates in good yields. The reaction involves easily accessible N,S-acetals obtained from cost-effective basic ketones and cysteamine as starting materials. This process ultimately leads to 1,4-thiazines related to natural product and fused derivatives necessary for further QSAR study. 相似文献