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141.
Newly synthesized Cu(II) pyrazino[2,3‐f][1,10]phenanthroline complexes as potential anticancer candidates 下载免费PDF全文
New binary and ternary copper(II) complexes, [Cu(py‐phen)2(NO3)]NO3 ( 1 ), [Cu2(py‐phen)2(gly)2(NO3)2(H2O)2]?3H2O ( 2 ) and [Cu2(py‐phen)2(tyr)2(H2O)2](NO3)2?3H2O ( 3 ) (py‐phen: pyrazino[2,3‐f][1,10]phenanthroline; gly: glycine; tyr: tyrosine), have been synthesized and characterized using CHN analysis, electrospray ionization mass spectrometry, Fourier transform infrared spectroscopy and single‐crystal X‐ray diffraction. Interaction of these complexes with calf thymus DNA has been investigated using absorption spectral titration, ethidium bromide and Hoechst 33258 displacement assay and thermal denaturation measurements. These complexes were found to be efficient cleaving agents and cleavage reactions were mediated by hydrolytic and oxidative pathways. The interaction between these complexes and bovine serum albumin (BSA) was investigated using electronic absorption and fluorescence spectroscopy. The experimental results show that the fluorescence quenching mechanism of these complexes and BSA is a static quenching process. Furthermore, in vitro cytotoxicities of these complexes against tumour cell lines (Caco‐2, MCF‐7 and A549) and healthy cell line (BEAS‐2B) showed that they exhibited anticancer activity with low IC50 values. These complexes were markedly active against the cell lines and can be good drug candidates that are effective and safe for healthy tissue. 相似文献
142.
We report critical coupling of electromagnetic waves to plasmonic cavity arrays fabricated on Moiré surfaces. Dark field plasmon microscopy imaging and polarization dependent spectroscopic reflection measurements reveal the critical coupling conditions of the cavities. The critical coupling conditions depend on the superperiod of the Moiré surface, which also defines the coupling between the cavities. Complete transfer of the incident power can be achieved for traveling wave plasmonic resonators, which have a relatively short superperiod. When the superperiod of the resonators increases, the coupled resonators become isolated standing wave resonators in which complete transfer of the incident power is not possible. Analytical and finite difference time domain calculations support the experimental observations. 相似文献
143.
Edink E Rucktooa P Retra K Akdemir A Nahar T Zuiderveld O van Elk R Janssen E van Nierop P van Muijlwijk-Koezen J Smit AB Sixma TK Leurs R de Esch IJ 《Journal of the American Chemical Society》2011,133(14):5363-5371
Optimization of fragment hits toward high-affinity lead compounds is a crucial aspect of fragment-based drug discovery (FBDD). In the current study, we have successfully optimized a fragment by growing into a ligand-inducible subpocket of the binding site of acetylcholine-binding protein (AChBP). This protein is a soluble homologue of the ligand binding domain (LBD) of Cys-loop receptors. The fragment optimization was monitored with X-ray structures of ligand complexes and systematic thermodynamic analyses using surface plasmon resonance (SPR) biosensor analysis and isothermal titration calorimetry (ITC). Using site-directed mutagenesis and AChBP from different species, we find that specific changes in thermodynamic binding profiles, are indicative of interactions with the ligand-inducible subpocket of AChBP. This study illustrates that thermodynamic analysis provides valuable information on ligand binding modes and is complementary to affinity data when guiding rational structure- and fragment-based discovery approaches. 相似文献
144.
In the present study, maleimide‐modified epoxide resin containing UV‐curable hybrid coating materials were prepared and coated on polycarbonate substrates in order to improve their surface properties. UV‐curable, bismaleimide‐modified aliphatic epoxy resin was prepared from N‐(p‐carboxyphenyl) maleimide (p‐CPMI) and cycloaliphatic epoxy (Cyracure‐6107) resin. The structure of the bismaleimide modified aliphatic epoxy resin was analyzed by FTIR and the characteristic absorption band for maleimide ring was clearly observed at 3100 cm?1. Silica sol was prepared from tetraethylorthosilicate (TEOS) and methacryloxy propyl trimethoxysilane (MAPTMS) by sol–gel method. The coating formulations with different compositions were prepared from UV‐curable bismaleimide‐based epoxy oligomer and sol–gel mixture. The molecular structure of the hybrid coating material was analyzed by 29Si‐CP/MAS NMR spectroscopy techniques. In the 29Si CP/MAS NMR spectrum of the hybrid coating, mainly two kinds of signals were observed at ?68 and ?110 ppm that correspond to T3 and Q4 peaks, respectively. This result shows that a fully condensed structure was obtained. The thermal and morphological properties of these coatings materials were investigated by using TGA and SEM techniques. Hardness and abrasion resistance properties of coating materials were examined and both were found to increase with sol–gel precursor content of the coating. The photopolymerization kinetics was investigated by using RT‐IR. 70% conversion was attained with the addition of 15 wt% of BMI resin into the acrylate‐based coating formulation. It was found that the UV‐curable organic–inorganic hybrid coatings improved the surface properties of polycarbonate. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
145.
Sülin Ta?c?o?lu Adnan Ayd?nBahattin Yalç?n Esra Kak?Ömer Andaç Orhan BüyükgüngörBa?ak Ko?ar 《Polyhedron》2011,30(13):2171-2180
Four copper(II) coordination polymers, {[Cu(pz(COO)2)(H2O)]4·HBr}n (1), {[Cu(pz(COO)2)(NH3)2]·H2O}n (2), {[Cu3H2(pz(COO)2)4(H2O)3]·2H2O}n (3) and {[Cu2(pz(COO)2)2(NH3)2(H2O)3][Cu(pz(COO)2)(NH3)(H2O)2][Cu(pz(COO)2)(NH3)(H2O)]·2H2O}n (4) were synthesized using pyrazine-2,3-dicarboxylic acid, CuBr2, 2-(2-aminoethylamino)ethanol/triethanol amine/ammonia in a methanol:water (1:1) solution, and the mixed ligand complexes were characterized by spectroscopic methods, thermal and elemental analysis, and magnetic susceptibility. Complexes 2 and 4 were also characterized by means of single crystal X-ray crystallography. The characterizations show that the complexes have polynuclear molecular structures, except for complex 2, and all of the complex structures form polymeric chains. Complex 4 has a pseudo-merohedral twin structure. 相似文献
146.
M. Abdur Rouf Imran Vural Erem Bilensoy Atilla Hincal Dilek Demir Erol 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(1-2):167-175
The objective of this study was to improve poor aqueous solubility and dissolution properties of anticancer drug rapamycin through formation of inclusion complexes with natural and modified cyclodextrins. Of the cyclodextrins tested, ??-cyclodextrin and hydroxypropyl-??-cyclodextrin did not complex with rapamycin. However, complexes of rapamycin with ??-cyclodextrin, methyl-??-cyclodextrin and hydroxypropyl-??-cyclodextrin were prepared and characterized by techniques such as Fourier Transform infrared spectroscopy, differential scanning calorimetry, phase solubility analysis and in vitro dissolution studies. According to the characterization data for the complexes, rapamycin water solubility was highly enhanced by all three ??-cyclodextrins with methyl-??-cyclodextrin complex resulting in particularly higher solubility enhancement. FTIR spectra and DSC thermograms supported the formation of inclusion complexes. The complexes showed highly improved dissolution rate in water. Complexation with cyclodextrin derivatives such as methyl-??-cyclodextrin and hydroxypropyl-??-cyclodextrin can provide promising alternatives for the formulation of rapamycin. 相似文献
147.
Synthesis of Dibutadienyl Piperazines, 1,1-Dithio and 1,4-Dithio Substituted Dienes from Nitrodienes
Cemil İbiş Gökşin Aydınlı 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2529-2535
Nitrodiene 1a , 1b reacted with 1,4-dithiolbutan and gave the heterocyclic compounds 3a , 3b . 1b gave with 1,3-acetonedithiol the compound 5b . The nitrodiene compound 1b reacted with o-dithiolbenzene ( 6 ) and yielded the ketene dithioacetal ( 7b ). Heterocyclic compounds 11a , 11b , 12a , and 12b were prepared from the reactions of 9a with 2,2'-oxydiethanethiol. The compounds 9a , 9b were prepared from 2-nitropentachloro-1,3-butadiene and alkylthiols ( 8a , 8b ). Mono(thio) substituted diene compound 9b gave dibutadienyl piperazine 14b with piperazine in diethylether. 相似文献
148.
Eren Esin Aydın Mihrace Filiz Oksuz Aysegul Uygun 《Journal of Solid State Electrochemistry》2020,24(4):1057-1065
Journal of Solid State Electrochemistry - We managed to provide one-step facile electrochromic device (ECD) preparation to incorporate two cathodic coloring components into lithium ion (Li+)-doped... 相似文献
149.
Hakan Bektaş Bahar B. Sökmen Sinem Aydın Emre Menteşe Adile Bektaş Gamze Dilekçi 《Journal of heterocyclic chemistry》2020,57(5):2234-2242
A new series of benzimidazole derivatives ( 1-15 ) containing 1,2,4-triazole, 1,3,4-thiadiazole, 1,3,4-oxadiazole, and thiazolidinon rings have been synthesized. All new synthesized benzimidazole compounds were confirmed by 1H NMR, 13C NMR spectra, and LC-MS, and they were examined for their antioxidant and antimicrobial activities. Compounds 7 and 1 showed the highest and the lowest antioxidant activities, respectively. The lowest minimum inhibition concentration value found in compound 5 against Enterobacter aerogenes. 相似文献
150.
Abstract Aromatic aldehydes 1 were reductively aminated to the corresponding secondary amines 2 using NaBH4 in methanol in good yields. Amines 2 were oxidized with H2O2‐WO4 2? regioselectively to nitrones 3, the structures of which were easily determined by reacting them with hydroxylamine hydrochloride as well as by spectral means. The products of hydroxylaminolysis in ether proved to be the corresponding benzaldehyde oximes 4 and benzyl or methyl hydroxylamine hydrochlorides 5. 相似文献