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41.
A series of novel racemic 2‐(1,3‐diaryl‐3‐hydroxypropyl)cyclohexan‐1‐ol derivatives were synthesized from 1,5‐diketones. All the synthesized compounds were characterized by spectroscopic methods. The antibacterial activities of obtained chiral 1,5‐diols were investigated against four Gram‐positive and three Gram‐negative bacteria by determining of minimum inhibitory concentrations (MICs) in vitro. Compounds 3b , 3c , and 3d were found to be active against Enterococcus faecalis and Escherichia coli. In addition, compound 3j were found to be moderately active against all tested bacterial strains.  相似文献   
42.
Journal of Solid State Electrochemistry - Porous cathodes are preferred to be used in lithium-sulfur (Li–S) batteries for better impregnation of the active material. On the other hand, the...  相似文献   
43.
A novel tetradentate azo‐Schiff base ligand (H2L) was synthesized by 2:1 molar condensation of an azo‐aldehyde and ethylenediamine. Its mononuclear Cu(II), Ni(II), Co(II) and Zn(II) complexes were prepared and their structures were confirmed using elemental analysis, NMR, infrared and UV–visible spectroscopies and molar conductivity measurements. The results suggest that the metal ion is bonded to the tetradentate ligand through phenolic oxygens and imine nitrogens of the ligand. The solid‐state structures of the azo‐Schiff base ligand and its Cu(II) complex were determined using single‐crystal X‐ray diffraction studies. The azo‐Schiff base ligand lies on a crystallographic inversion centre and thus the asymmetric unit contains half of the molecule. X‐ray data revealed that keto–amine tautomer is favoured in the solid‐state structure of the ligand. In the structure of the Cu(II) complex, the Cu(II) ion is coordinated to two phenolate oxygen atoms and two imine nitrogen atoms of the azo‐Schiff base ligand with approximate square planar geometry. The anticancer activity of the synthesized complexes was investigated for human cancer cell line (MCF‐7) and cytotoxicity of the synthesized compounds was determined against mouse fibroblast cells (L929). The ligand and its complexes were found to show antitumor activity. The synthesized metal complexes were optimized at the B3LYP/LANL2DZ level and a new theoretical formula for MCF‐7 cells was also derived.  相似文献   
44.
45.
In this work, we derive the Euler-Lagrange equation for an elastic line which is lying on a pseudo-hypersurface in pseudo-Euclidean spaces . Following this, we check the solutions which depend on the boundary conditions whether they are geodesic on a pseudo-hypersurface or not. The relaxed elastic line on a pseudo-hyperplane, a pseudo-hypersphere, and pseudo-hyperbolic space is a geodesic. However, the relaxed elastic line on a pseudo-hypercylinder, is a space-like geodesic.  相似文献   
46.

In the present study, pure bentonite and bentonite modified by HNO3, EDTA, and HDTMA are adsorbents. The changes on the surfaces of bentonite samples are studied by IR spectroscopy. The adsorption of aniline, phenol, and phenol derivatives on these adsorbents is examined by means of gas chromatography. As the result of these examinations, it is seen that the adsorption capacities of clay-organic complexes (bentonite-EDTA and bentonite-HDTMA) are higher than those of bentonite-HNO3 and pure bentonite.

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47.
3‐Aryl‐2‐benzoylbenzofurans were synthesized by the reaction of α‐carboradical produced from dimedon by oxidizing with manganese(III) acetate in acetic acid and the chalcone derivatives.  相似文献   
48.
A series of chalcone derivatives containing thioglicolic acid (4a–j) was prepared by addition of thioglicolic acid to the chalcones (3a–j) in the presence of KOt-Bu under solvent-free conditions. The mechanistic pathway of the reaction can be explained by the Michael-type addition of thioglicolic acid to chalcone derivatives (3a–j).  相似文献   
49.
Ionone-based terpenoid-like bischalcones (3ah and 4ah) were synthesized from the reaction of α- and/or β-ionones with aldehyde derivatives in excellent yields. The antibacterial activities of synthesized compounds were screened against human pathogenic micro-organisms by employing the disk-diffusion technique.  相似文献   
50.
The objective of this study was to investigate the effects of high hydrostatic pressure (HHP) on the stability of red blood cells (RBCs) and platelets. Bovine blood cells (n=5) were treated with the pressure of 55, 110, 154 and 220 MPa at 25 °C for 5 min. Light microscopy, atomic force microscopy and flow cytometry studies revealed that RBCs were morphologically stable up until the 220 MPa pressure treatments, at which surface modifications were observed. The platelets were found to be less stable than RBCs. HHP application did not cause any significant change in the signal intensity, band area and frequency values of the infrared bands with the exception that a significant variation was observed in the area of the cholesterol band. No statistically significant variations were observed in the secondary structure elements due to HHP treatment according to the artificial neural network study based on the FTIR data.  相似文献   
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