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101.
Synthesis of poly(?-caprolactone-b-ethylene glycol-b-?-caprolactone) ABA type block copolymer by “click” chemistry and ring-opening polymerization (ROP) was reported by using propargyl polyethylene glycol (propargyl-PEG) and terminally azido poly(?-caprolactone) ester (PCL-N3). For this purpose, primarily propargyl-PEG was synthesized by using reaction of PEGs (3000 Da, 2000 Da, 1500 Da, 1000 Da, 600 Da ve 400 Da) and propargyl chloride. 3-azido-1-propanol was obtained by using chemical interaction of 3-chloro-1-propanol and sodium azide. Synthesis of PCL-N3 was carried out by means of ROP of ?-caprolactone and 3-azido-1-propanol. Finally, poly(?-caprolactone-b-ethylene glycol-b-?-caprolactone) ABA type block copolymers were synthesized by using PCL-N3 and propargyl-PEG. The primary parameters such as concentration, time, and temperature that influenced the reactions were assessed. The product characterization was achieved using NMR, FT-IR, GPC, elemental analysis, and fractional precipitation [non-solvent (petroleum ether-mL)/solvent (THF-mL)] techniques. 相似文献
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Handan Günay Alper Tolga Çolak Ersin Temel Özlem Saniye Bayraktar Ferdağ Çolak Orhan Büyükgüngör 《Journal of Coordination Chemistry》2016,69(9):1499-1513
Two coordination polymers with 5-aminoisophthalic acid (H2aip), [Ni(μ-aip)(H2O)2(tmeda)]n (1) and {H2dap[Zn2(μ-aip)(μ3-aip)2]?9H2O}n (2) (H2aip = 5-aminoisophthalic acid, tmeda = N,N,N′-N′-tetramethylethylenediamine, dap = 1,3-diaminopropane) have been synthesized. Elemental and thermal analyses, magnetic susceptibilities, IR, AAS, mass and UV–vis spectroscopic studies have been performed to characterize the compounds. Nickel(II) has octahedral geometry by two oxygens of different carboxylates, bidentate, tmeda as bidentate chelating and two water ligands. Zn(II) has tetrahedral geometry by three oxygens of different carboxylate groups and one nitrogen by amine of aip. 1 crystallizes in the orthorhombic crystal system with space group Pccn and 2 in monoclinic crystal system with space group P21/c. Complex 2 exhibits photoluminescence properties in the solid state at room temperature. This study determined the susceptibility patterns of 1 and 2 against bacterial, yeast and mold micro-organisms. Antimicrobial activities were done on 12 different micro-organisms using the micro-dilution method. Tested microbial species were inhibited by 1 with a Minimum inhibitory concentrations (MIC) of 375–3000 μg mL?1. Compound 2 showed antimicrobial activities against tested micro-organisms with a MIC of 188–1500 μg mL?1. Compound 2 showed antibacterial activity against Legionella pneumophila sg1 375 μg mL?1 (MIC value). 相似文献
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Abdelhakim Bouyahya Aicha El Allam Ikrame Zeouk Douae Taha Gokhan Zengin Bey Hing Goh Michelina Catauro Domenico Montesano Nasreddine El Omari 《Molecules (Basel, Switzerland)》2022,27(1)
Grifolin is a volatile compound contained in essential oils of several medicinal plants. Several studies show that this substance has been the subject of numerous pharmacological investigations, which have yielded interesting results. Grifolin demonstrated beneficial effects for health via its multiple pharmacological activities. It has anti-microbial properties against bacteria, fungi, and parasites. In addition, grifolin exhibited remarkable anti-cancer effects on different human cancer cells. The anticancer action of this molecule is related to its ability to act at cellular and molecular levels on different checkpoints controlling the signaling pathways of human cancer cell lines. Grifolin can induce apoptosis, cell cycle arrest, autophagy, and senescence in these cells. Despite its major pharmacological properties, grifolin has only been investigated in vitro and in vivo. Therefore, further investigations concerning pharmacodynamic and pharmacokinetic tests are required for any possible pharmaceutical application of this substance. Moreover, toxicological tests and other investigations involving humans as a study model are required to validate the safety and clinical applications of grifolin. 相似文献
105.
Transformation of mean chain dimensions in a bimodal Gaussian network is analyzed by generating a two-dimensional trifunctional network using Monte Carlo technique and deforming it, subject to the balance of mean forces at each junction. Instantaneous fluctuations in chain dimensions are not considered in the simulations. The problem is, therefore, equivalent to the analysis of a two-dimensional deterministic system of two sets, short and long, of linear springs, joined at trifunctional junctions. The molecular deformation of network chains, the distribution of orientation of chain vectors and the reduced stresses are studied as a function of extension ratio and network topology. 相似文献
106.
In this study,the electronic transition properties and structural analysis of the metal complexes(Ni(Ⅱ),Co(Ⅱ),Cu(Ⅱ)and Mn(Ⅱ))of three different polymer ligands were performed by using XRF and X-ray diffraction(XRD)techniques,respectively.The structural analysis of the polymers and their complexes were performed by XRD technique and some of the polymers were found to be in the face-centred cubic(fcc)structure.In addition,the values of the present K X-ray intensity ratios are significantly greater than the values reported in literature. 相似文献
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Lucia Recinella Annalisa Chiavaroli Viviana di Giacomo Marco Daniel Antolini Alessandra Acquaviva Sheila Leone Luigi Brunetti Luigi Menghini Gunes Ak Gokhan Zengin Simonetta Cristina Di Simone Claudio Ferrante Giustino Orlando 《Molecules (Basel, Switzerland)》2021,26(1)
Tanacetum parthenium (feverfew) has traditionally been employed as a phytotherapeutic remedy in the treatment of migraine. In this study, a commercial T. parthenium water extract was investigated to explore its anti-inflammatory and neuromodulatory effects. Isolated mouse cortexes were exposed to a K+ 60 mM Krebs-Ringer buffer and treated with T. parthenium water extract. The prostaglandin E2 (PGE2) level, brain-derived neurotrophic factor (BDNF), interleukin-10 (IL-10), and IL-1β gene expression were evaluated in the cortex. The effects on dopamine (DA) release and dopamine transporter (DAT) gene expression were assayed in hypothalamic HypoE22 cells. A bioinformatics analysis was conducted to further investigate the mechanism of action. The extract was effective in reducing cortex PGE2 release and IL-1β gene expression. In the same experimental system, IL-10 and BDNF gene expressions increased, and in HypoE22 cells, the extract decreased the extracellular dopamine level and increased the DAT gene expression due to the direct interaction of parthenolide with the DAT. Overall, the present findings highlight the efficacy of T. parthenium water extract in controlling the inflammatory pathways that occur during cortical-spreading depression. Additionally, the inhibition of the hypothalamic DA release observed in this study further supports the role of dopaminergic pathways as key targets for novel pharmacological approaches in the management of migraine attacks. 相似文献
110.