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201.
New polymeric ligand (resin) was prepared by the condensation of thiosemicarbazides with formaldehyde in the presence of acidic medium. Thisemicarbazide–formaldehyde polymer–metal complexes were prepared with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) in 1:2 metal:ligand molar ratio. The polymeric ligand and its polymer–metal complexes were characterized by elemental analysis, thermogravimetric analysis (TGA), FTIR, 13C NMR and 1H NMR. The geometry of central metal ions was conformed by electronic (UV–vis) and EPR spectra. The antibacterial activities of all the synthesized polymers were investigated against Bacillus subtilis and Staphylococcus aureus (Gram‐positive) and Escherichia coli and Salmonella typhi (Gram‐negative). These compounds showed excellent activities against these bacteria using the shaking flask method. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
202.
A new polyester, poly‐(ethylene oxamide‐N,N′‐diacetate) (PEODA), containing glycine moiety was synthesized by the reaction of oxamide‐N,N′‐diacetic acid and ethylene glycol and its polymer–metal complexes were synthesized with transition metal ions. The monomer oxamide‐N,N′‐diacetic acid was prepared by the reaction of glycine and diethyl oxalate. The polymer and its metal complexes were characterized by elemental analysis and other spectroscopic techniques. The in vitro antibacterial activities of all the synthesized polymers were investigated against some bacteria and fungi. The analytical data revealed that the coordination polymers of Mn(II), Co(II) and Ni(II) are coordinated with two water molecules, which are further supported by FTIR spectra and TGA data. The polymer–metal complexes showed excellent antibacterial activities against both types of microorganisms; the polymeric ligand was also found to be effective but less so than the polymer–metal complexes. On the basis of the antimicrobial behavior, these polymers may be used as antifungal and antifouling coating materials in fields like life‐saving medical devices and the bottoms of ships. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
203.
Nahid Nishat Sumaiya Hasnain Tansir Ahmad Asma Parveen 《Journal of Thermal Analysis and Calorimetry》2011,105(3):969-979
The production of new biocidal polyester Schiff base metal complexes [PESB–M(II)] via polycondensation reaction between chelated
Schiff base diol and adipoyl chloride is reported. The resulting polyesters were characterized by physico-chemical and spectroscopic
methods. The analytical data of all the synthesized polyesters were found to be in good agreement with 1:1 molar ratio of
chelated Schiff base diol to adipoyl chloride. Thermogravimetric analyses of synthesized polyesters were studied by TG in
nitrogen atmosphere up to 1073 K and results indicate that Cu(II) polyester complex exhibited better heat resistant properties
than the other polyesters complexes. Magnetic moment and UV–visible spectra were examined to explain the structure of all
the polyesters which reveled that Mn(II), Co(II), Ni(II) have octahedral geometry while Cu(II) possess a distorted octahedral
geometry. These newly developed polyesters were also tested for their antibacterial activity against several bacteria and
fungi. Among all the tested compounds PESB–Cu(II) possess the highest bactericidal and fungicidal activity. 相似文献
204.
Shahabadi N Fatahi N Mahdavi M Nejad ZK Pourfoulad M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,83(1):420-424
The present study investigated the binding interaction between an antiviral drug, valacyclovir and calf thymus DNA (CT-DNA) using emission, absorption, circular dichroism, viscosity and DNA melting studies. In fluorimetric studies, thermodynamic enhancement constant (K(D)) and bimolecular enhancement constant (K(B)) were calculated at different temperatures and demonstrated that fluorescence enhancement is not initiated by a dynamic process, but instead by a static process that involves complex DNA formation in the ground state. Further, the enthalpy and entropy of the reaction between the drug and CT-DNA showed that the reaction is exothermic and enthalpy-favored. In addition, detectable changes in the circular dichroism spectrum of CT-DNA in the presence of valacyclovir indicated conformational changes in the DNA double helix following interaction with the drug. All these results prove that this antiviral drug interacts with CT-DNA via an intercalative mode of binding. 相似文献
205.
Mohammad Ali Karimi Zarchi Nahid Ebrahimi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1226-1235
Abstract An efficient and simple method for the facile synthesis of arylthiocyanates via diazotization-thiocyanation of aryl amines using cross-linked poly (4-vinylpyridine) supported thiocyanate ion is described. Various primary aromatic amines, with electron-withdrawing and electron-donating groups, were transformed into aryl thiocyanates in high to excellent yields in a short reaction time. The present procedure offers advantages such as short reaction time, simple reaction work-up, and the polymeric reagents can also be regenerated and reused for several times without significant loss of their activity. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
206.
Öztürk Tuğçe Pınar Gelir Ali Keshtiban Nahid Aghabalapoor Yargı Önder Özdemir Onur B. Mucur Selin Pıravadılı Seçgin Alper 《Journal of Solid State Electrochemistry》2023,27(4):885-894
Journal of Solid State Electrochemistry - The motion of the ion pairs under the applied electric field is an important phenomenon in the storage properties of the capacitive devices. In this study,... 相似文献
207.
Kimia Hafezi Motlagh Arash Azizi Nahid Moezzi Ghadim 《Photochemistry and photobiology》2023,99(3):920-928
Low-level laser therapy (LLLT) has several benefits in dentistry, including anti-inflammatory effects and increased proliferation. This study aimed to investigate the effect of 445 nm blue laser and 660 nm low-power laser on the quantity and quality of human gingival fibroblasts in vitro. In this in vitro experimental study, 445 nm and 660 nm lasers were irradiated on the samples six times. After examining the cells on the 7th and 14th days, the data were analyzed using ANOVA PASS11 and the post hoc Tukey test. The results showed the positive effect of the 660 nm laser on fibroblast proliferation. The viability on the 7th day was the highest in the control group, lowest in the 445 nm laser group and highest in the 660 nm laser group on the 14th day. In the morphological examination, the cells were spherical with narrow appendages in the control group, spindle-shaped with lamellipodia appendages in the 660 nm laser group and spherical with no cytoplasmic appendages in the 445 nm laser group. Evidence of necrosis and granulation phenomenon was observed in the 445 nm laser group. The use of the 660 nm low-power laser, compared with the 445 nm laser, has a positive effect on the quantity and quality of gingival fibroblasts. 相似文献