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11.
Novel quinolone derivatives featuring an 1,3,4-oxadiazole ring as a metal-chelating component and a benzyl group base on HIV-1 integrase inhibitors pharmacophore were designed and synthesized. An antiviral assay revealed that most analogues inhibited HIV-1 replication in the cell culture. Our results showed that compounds bearing small alkyl groups as R group were inactive in anti-HIV-1 assay, whereas compounds possessing benzyl or substituted benzyl at the same position showed good anti-HIV activity with the range of 20–57% at 100 μM concentration. Among them, 3-(5-((2-fluorobenzyl)thio)-1,3,4-oxadiazol-2-yl)-8-phenylquinolin-4-(1H)-one (compound 13) showed reasonable cell-based antiviral activity (EC50 = 50 μM) with no considerable cytotoxicity (CC50 > 100 μM) in the cell viability assay, suggesting that it may be amenable to further development for identifying new anti-HIV-1 agents. Docking studies using the later crystallographic data available for PFV integrase corroborate favorable binding to the active site of HIV integrase, providing a basis for the design of more potent analogues.  相似文献   
12.
Abstract  A new route to the synthesis of 2-arylthieno[2,3-d]pyrimidin-4(3H)-ones has been developed through heterocyclization of 2-amino-4,5-dimethylthiophene-3-carboxamide with aromatic aldehydes in boiling glacial acetic acid followed by air oxidation. The unoxidized intermediates, 2-aryl-2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-ones, are isolated when the reactions are carried out either at room temperature or under a nitrogen atmosphere. Graphical Abstract     相似文献   
13.
A new ruthenium/dendrimer complex stabilized on the surface of silica-functionalized nano-magnetite was fabricated and well characterized. The nano-catalyst showed good activity in the synthesis of benzil derivatives via the oxidation of stilbenes with high turnover frequency (TOF) at room temperature. Moreover, the catalyst could also be reused up to fifteen times without any loss of its activity.  相似文献   
14.
Grass waste was used for transform an inexpensive waste into health. Silver nanoparticles (AgNPs) have been synthesized using waste material (dried grass). The average size of silver nanoparticles observed in transmission electron images was estimated to be about 15?nm. The anticancer, antifungal and antibacterial effect of AgNPs were studied in vitro. The minimum inhibitory concentration of AgNPs against Pseudomonas aeruginosa and Acinetobacter baumannii was calculated about 3?µg/ml. The highest level of inhibitory effect of AgNPs against Fusarium solani was close to 90% at a concentration of 20?μg/ml of AgNPs. An inhibitory effect on the cancer cell growth is reach, by increasing the concentration of AgNPs to 5?µg/ml; the cancer cells’ survival decreases about 30%. Western results showed that the expression of Cyclin D1 protein of MCF-7 cell line decreased after treatment with the effective concentration of AgNPs.  相似文献   
15.
In this work, surfactant-coated Fe3O4@decanoic acid nanoparticles was synthesized as a viable nanosorbent for coextraction of drugs with different polarities (hydrophobic, hydrophilic). To reach desirable enrichment factors, efficient clean-up and low limits of detection (LODs), the method was combined with dispersive liquid–liquid microextraction (DLLME). The coupling of these extraction methods with GC-FID detection was applied to simultaneous extraction and quantification of venlafaxine (VLF) as a hydrophilic model drug and desipramine (DESI) and clomipramine (CLO) as hydrophobic model drugs in urine samples. The effect of sample pH, nanosorbent amount, sorption time, surfactant concentration, eluent type, eluent volume, salt content, elution time in magnetic solid phase extraction step and extraction solvent and its volume along with sample pH in DLLME step were optimized. Under the selected conditions, linearity was achieved within the range of 5–5000 µg L?1. The LOD values were obtained in the range of 1.5–3.0 µg L?1 for DESI, 1.2–2.5 µg L?1 for VLF and 2.0–4.0 µg L?1 for CLO, respectively. The percent of extraction recoveries and relative standard deviations (n?=?5) were in the range of 82.4–95.9 and 6.1 for DESI, 60.5–92.8 and 6.9 for VLF and 57.2–58.0 and 5.5 for CLO, respectively. Ultimately, the applicability of the new method was successfully confirmed by the extraction and quantification of DESI, VLF and CLO from human urine samples.  相似文献   
16.
17.
The present study attempts to develop a detailed numerical approach and a simulation procedure to predict the motion of gas, ions and particles inside a simple parallel plate channel containing a single corona wire. A hybrid Finite Element (FEM)-Flux Corrected Transport (FCT)-Finite Volume (FVM) method is used: the FEM–FCT numerical algorithm is applied for modeling the steady-state corona discharge, while the turbulent gas flow and the particle motion under electrostatic forces are modeled using the commercial CFD code FLUENT. Calculations for the gas flow are carried out by solving the Reynolds-averaged Navier–Stokes equations and turbulence is modeled using the k? turbulence model. An additional source term is added to the gas flow equation to include the effect of the electric field, obtained by solving a coupled system of the electric field and charge transport equations using User-Defined Functions (UDFs). The particle phase is simulated based on the Lagrangian approach, where a large number of particles is traced with their motion affected by the gas flow and electrostatic forces using the Discrete Phase Model (DPM) in FLUENT. The developed model is useful to gain insight into the particle collection phenomena that take place inside an ESP.  相似文献   
18.

Abstract  

Efficient and convenient synthesis of β-acetamido ketones has been achieved by one-pot reaction of acetophenone, aryl aldehydes, acetyl chloride, and acetonitrile in the presence of 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogensulfate [HO3S(CH2)4MIM][HSO4], a Br?nsted-acidic ionic liquid, as a green and reusable catalyst in solvent-free media at room temperature. The catalyst could be recycled and reused without noticeable decrease in catalytic activity.  相似文献   
19.
A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one‐pot, four‐component unsymmetrical Hantzsch condensation of dimedone, aldehydes, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate [TBA]2[W6O19] under solvent‐free conditions has been developed. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and considerable catalytic activity was still achieved after the fifth run.  相似文献   
20.
Oscillating chemical reactions are complex systems, involving a large number of chemical species. In oscillating chemical reaction, some species, usually a reaction intermediate, exhibit fluctuation in its concentration. In this report, visible oscillating chemiluminescence produced by the addition of luminol (3-aminophthalhydrazide) to the oscillating system of H2O2=KSCN=CuSO4=TMAOH was investigated using spectrofluorimetry method. The effects of ingredient concentration of the oscillating system and complexing agents like citric acid and cysteine on the behavior of the oscillating system were investigated. Moreover, the influence of nonaqueous solvents such as ethanol and ethylene glycol has been studied.  相似文献   
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