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61.
Nesrin Karaali Serdar Aydin Nimet Baltas Emre Mentese 《Journal of heterocyclic chemistry》2020,57(4):1806-1815
A new series of 5,6-dimethyl-2-phenyl-1H-benzimidazole derivatives was synthesized. The antioxidant activities of the synthesized compounds were determined according to the cupric reducing antioxidant capacity (CUPRAC), ABTS, and DPPH assays. Many of the target compounds showed good antioxidant activity. Among these compounds, it has been determined that the carbothioamide and 1,2,4-triazole derivatives had a very good antioxidant capacity. Also, all compounds were screened for in vitro inhibitory activity against Jack bean urease. Among the synthesized molecules, the starting compound, acetate, and acetohydrazide derivatives (with IC50 values 12.02, 11.40, and 8.04 μg/mL, respectively) had a higher inhibitory effect on urease and exhibited a lower IC50 values than acetohydroxamic acid (IC50: 20.50 μg/mL) and thiourea (IC50: 14.04 μg/mL) as a reference inhibitors. 相似文献
62.
63.
In this study, nanofiber structures were obtained with convenient polymers (PVA [polyvinyl alcohol] and PCL [poly o-caprolactone]) derived from the herbal extracts of olive leaves, fumitory, and terebinth plants. Optimum nanofiber structures were identified by measuring viscosity and conductivity values and performing morphological analysis, characterization, and mechanical tests of the prepared solutions. The potential use for wound healing at the most efficient level was determined as a result of antibacterial analysis of the structures obtained. APT (PVA/terebinth) and BFO (PCL/fumitory) nanofibers had the thinnest diameter range and the highest strength values. In terms of the determination of antibacterial effects, nanofiber structures of all 3 plant species proved to be effective against bacteria. The greatest effect was observed against Escherichia coli in the nanofiber structure containing olive leaves, with a zone diameter of 32 mm. In addition, APT and BFO nanofibers had the highest values of thinness and strength. In these 2 samples, using BFO against Staphylococcus aureus and APT against Candida albicans increased their areas of activity. In the literature review, no study was available about obtaining nanofibers, especially from fumitory and terebinth plants. This study aimed to increase knowledge on obtaining nanofiber structures, including various polymers derived from olive leaves, fumitory, and terebinth plants. 相似文献
64.
A squarate-based synthesis of 2-ferrocenylidene-4-cyclopentene-1,3-diones is described. When refluxed in dioxane at 100 °C, heated with silica gel as a solvent free grinded solid mixture at 125 °C or stirred with silica gel in ethyl acetate at room temperature, 4-ferrocenylethynyl-4-hydroxy-2-cyclobutenones, prepared from ethynylferrocene and 3-cyclobutene-1,2-diones, afforded 2-ferrocenylidene-4-cyclopentene-1,3-diones as the major or single product of the reaction. In some cases, ferrocenyl quinones also resulted from these reactions as the minor products. The major or exclusive formation of 2-ferrocenylidene-4-cyclopentene-1,3-diones is attributed to the radical-stabilizing ability of the ferrocenyl group. 相似文献
65.
This paper presents a numerical method based on Fluctuationlessness Theorem for the solution of Ordinary Differential Equations
over appropriately defined Hilbert Spaces. We focus on the linear differential equations in this work. The approximated solution
is written in the form of an nth degree polynomial of the independent variable. The unknown coefficients are obtained by setting up a system of linear equations
which satisfy the initial or boundary conditions and the differential equation at the grid points, which are constructed as
the independent variable’s matrix representation restricted to an n dimensional subspace of the Hilbert Space. An error comparison of the numerical solution and the MacLaurin series with the
analytical solution is performed. The results show that the numerical solution obtained here converges to the analytical solution
without using too many mesh points. 相似文献
66.
Aydin Tavman Serkan Ikiz A. Funda Bagcigil N. Yakut Özgür Seyyal Ak 《Russian Journal of Inorganic Chemistry》2010,55(2):215-222
2-Methyl-6-(5-H-methyl-chloro-nitro-1H-benzimidazol-2-yl)-phenols( HL x :x= 1-4)ligands and HL1 complexes with Fe(NO3)3, Cu(NO3)2, AgNO3, Zn(NO3)2 have been synthesized and characterized. The structures of the compounds were confirmed on the basis of elemental analysis, molar conductivity, magnetic moment, FT-IR, 1H-and 13C-NMR. Antibacterial activity of the free ligands, their hydrochloride salts and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide as well as the minimum inhibitory concentration dilution method, against nine bacteria. While HL1 ligand has not any activity, it’s Ag(I) complex show antibacterial effect toward almost to all the bacteria. Zn(II) complex has antibacterial effect on especially K. pneumoniae, S. epidermidis and S. aureus bacteria. 相似文献
67.
Murat Güney Selçuk Eşsiz Arif Daştan Metin Balci Ottorino De Lucchi Ertan Şahin Fabrizio Fabris 《Helvetica chimica acta》2013,96(5):941-950
Stereoisomerically pure endo‐ and exo‐7‐halo‐7‐(trimethylstannyl)benzonorcar‐3‐enes (=endo‐ and exo‐(1‐halo‐1a,2,7,7a‐tetrahydro‐1H‐cyclopropa[b]naphthalen‐1‐yl)trimethylstannane) 4 and 6 were selectively obtained by lithium? tin or magnesium? tin transmetalation in good yields (Scheme 2 and 3). The reaction of these compounds with copper(I) thiophene‐2‐carboxylate (CuTC) produced in both cases the corresponding CS‐symmetric bicyclopropylidene (=cyclopropylidenecyclopropane) syn‐ 1 , a single diastereoisomer (Schemes 5 and 6). The structure of syn‐ 1 was undoubtedly elucidated by X‐ray single crystal diffraction. The coupling mechanism of the carbenoid cyclopropane is discussed (Scheme 7). 相似文献
68.
Haydar Kilic Omer Aydin Sinan Bayindir Nurullah Saracoglu 《Journal of heterocyclic chemistry》2016,53(6):2096-2101
Bismuth nitrate catalyzed condensation reactions of indoline with 1,2‐ and 1,3‐diketones were investigated and were reported to proceed via different reaction pathways with the involvement of one or two of the carbonyl groups. While the reaction of indoline with cyclohexane‐1,3‐dione ( 4 ) gave solely condensation product, the reaction between the acetylacetone ( 5 ) and indoline provided N‐acetyl indoline as single products on retro‐aldol process. In contrast to 1,3‐diketones, the reaction with benzil ( 17 ) was performed under difficult conditions and proceeded to give secondary products. 相似文献
69.
This paper proposes an approximate adhesion model for fibrillar adhesives for developing a fibrillar adhesive design methodology and compares numerical simulation adhesion results with macroscale adhesion data from polymer microfiber array experiments. A technique for fabricating microfibers with a controlled angle is described for the first time. Polyurethane microfibers with different hardnesses, angles, and aspect ratios are fabricated using optical lithography and polymer micromolding techniques and tested with a custom tensile adhesion measurement setup. Macroscale adhesion and overall work of adhesion of the microfiber arrays are measured and compared with the models to observe the effect of fiber geometry and preload. The adhesion strength and work of adhesion behavior of short and long vertical and long angled fiber arrays have similar trends with the numerical simulations. A scheme is also proposed to aid in optimized fiber adhesive design. 相似文献
70.
(1R,2R)-1,2-bis-(5-amino-1,3,4-thiadiazole-2-yl)ethane-1,2-diol (L) has been prepared by the reaction of thiosemicarbazide with (2R,3R)-(+)-tartaric
acid (I) and phosphorous oxychloride, and its complexes with Co(II), Ni(II) and Cu(II) have been obtained. The structures
of the ligand and its complexes have been established by i. r., 1H- and 13C-n.m.r. spectra, u.v.–vis–nir spectroscopy, elemental analyses, T.g.-D.t.a. and magnetic susceptibility measurements. 相似文献