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1.
《国际聚合物材料杂志》2012,61(11):1059-1071
ABSTRACT Friedel-Crafts polyetherketones were prepared from o-chlorophenol, 1,4-phenylenedioxy diacetylchloride (1,4-PDC), chloroacetyl chloride (CAC), 1,2-dichloroethane (DCE), and dichloromethane (DCM) using anhydrous aluminium chloride (AlCl3) as catalyst and carbon disulfide (CS2) as solvent. These resins were characterized by IR spectroscopy and gel permeation chromatography. Carius method was employed to obtain the percentage of chlorine content in the resins. The kinetic parameters for the thermal behavior of the resins were evaluated from thermogravimetry (TG) using Broido method. Differential scanning calorimetry (DSC) thermograms of these resins were also obtained. All the polyetherketones were tested for their antimicrobial properties against bacteria, fungi, and yeast. It was observed that most of the polyetherketones synthesized could be used as antibacterial and antifungal agents. 相似文献
2.
Barbara Kubiak Aleksandra Radtke Adrian Topolski Grzegorz Wrzeszcz Patrycja Goliska Ewelina Kaszkowiak Micha Sobota Jakub Wodarczyk Mateusz Stojko Piotr Piszczek 《International journal of molecular sciences》2021,22(13)
Excessive misuse of antibiotics and antimicrobials has led to a spread of microorganisms resistant to most currently used agents. The resulting global threats has driven the search for new materials with optimal antimicrobial activity and their application in various areas of our lives. In our research, we focused on the formation of composite materials produced by the dispersion of titanium(IV)-oxo complexes (TOCs) in poly(ε-caprolactone) (PCL) matrix, which exhibit optimal antimicrobial activity. TOCs, of the general formula [Ti4O2(OiBu)10(O2CR’)2] (R’ = PhNH2 (1), C13H9 (2)) were synthesized as a result of the direct reaction of titanium(IV) isobutoxide and 4-aminobenzoic acid or 9-fluorenecarboxylic acid. The microcrystalline powders of (1) and (2), whose structures were confirmed by infrared (IR) and Raman spectroscopy, were dispersed in PCL matrixes. In this way, the composites PCL + nTOCs (n = 5 and 20 wt.%) were produced. The structure and physicochemical properties were determined on the basis of Raman microscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), electron paramagnetic resonance spectroscopy (EPR), and UV–Vis diffuse reflectance spectroscopy (DRS). The degree of TOCs distribution in the polymer matrix was monitored by scanning electron microscopy (SEM). The addition of TOCs micro grains into the PCL matrix only slightly changed the thermal and mechanical properties of the composite compared to the pure PCL. Among the investigated PCL + TOCs systems, promising antibacterial properties were confirmed for samples of PCL + n(2) (n = 5, 20 wt.%) composites, which simultaneously revealed the best photocatalytic activity in the visible range. 相似文献
3.
Synthesis,Characterization, and Antimicrobial Activity of Silver(I) and Copper(II) Complexes of Phosphate Derivatives of Pyridine And Benzimidazole 下载免费PDF全文
Dr. Urszula Kalinowska‐Lis Prof. Eligia M. Szewczyk Dr. Lilianna Chęcińska Dr. Jakub M. Wojciechowski Prof. Wojciech M. Wolf Prof. Justyn Ochocki 《ChemMedChem》2014,9(1):169-176
Two silver(I) complexes—{[Ag(4‐pmOpe)]NO3}n and [Ag(2‐bimOpe)2]NO3—and three copper(II) complexes—[Cu4Cl6O(2‐bimOpe)4], [CuCl2(4‐pmOpe)2], and [CuCl2(2‐bis(pm)Ope]—were synthesized by reaction of silver(I) nitrate or copper(II) chloride with phosphate derivatives of pyridine and benzimidazole, namely diethyl (pyridin‐4‐ylmethyl)phosphate (4‐pmOpe), 1H‐benzimidazol‐2‐ylmethyl diethyl phosphate (2‐bimOpe), and ethyl bis(pyridin‐2‐ylmethyl)phosphate (2‐bis(pm)Ope). These compounds were characterized by 1H, 13C, and 31P NMR as well as IR spectroscopy, elemental analysis, and ESIMS spectrometry. Additionally, molecular and crystal structures of {[Ag(4‐pmOpe)]NO3}n and [Cu4Cl6O(2‐bimOpe)4] were determined by single‐crystal X‐ray diffraction analysis. The antimicrobial profiles of synthesized complexes and free ligands against test organisms from the ATCC and clinical sources were determined. Silver(I) complexes showed good antimicrobial activities against Candida albicans strains (MIC values of ~19 μM ). [Ag(2‐bimOpe)2]NO3 was particularly active against Pseudomonas aeruginosa and methicillin‐resistant Staphylococcus epidermidis, with MIC values of ~5 and ~10 μM , respectively. Neither copper(II) complexes nor the free ligands inhibited the growth of test organisms at concentrations below 500 μg mL?1. 相似文献
4.
Joanna Drzedon Marta Pawlak Natalia Matyka Artur Sikorski Barbara Gawdzik Dagmara Jacewicz 《International journal of molecular sciences》2021,22(18)
Oxidative stress plays an important role in the pathogenesis of many serious diseases, including cancer, atherosclerosis, coronary artery disease, Parkinson’s disease, Alzheimer’s disease, stroke and myocardial infarction. In the body’s natural biochemical processes, harmful free radicals are formed, which can be removed with the help of appropriate enzymes, a balanced diet or the supply of synthetic antioxidant substances such as flavonoids, vitamins or anthocyanins to the body. Due to the growing demand for antioxidant substances, new complex compounds of transition metal ions with potential antioxidant activity are constantly being sought. In this study, four oxovanadium(IV) and dioxovanadium(V) dipicolinate (dipic) complexes with 1,10-phenanthroline (phen), 2,2′-bipyridyl (bipy) and the protonated form of 2-phenylpyridine (2-phephyH): (1) [VO(dipic)(H2O)2]·2 H2O, (2) [VO(dipic)(phen)]·3 H2O, (3) [VO(dipic)(bipy)]·H2O and (4) [VOO(dipic)](2-phepyH)·H2O were synthesized including one new complex, so far unknown and not described in the literature, i.e., [VOO(dipic)](2-phepyH)·H2O. The oxovanadium(IV) dipicolinate complexes with 1,10-phenanthroline and 2,2′-bipyridyl have been characterized by several physicochemical methods: NMR, MALDI-TOF-MS, IR, but new complex [VOO(dipic)](2-phepyH)·H2O has been examined by XRD to confirm its structure. The antioxidant activities of four complexes have been examined by the nitrotetrazolium blue (NBT) method towards superoxide anion. All complexes exhibit high reactivity with superoxide anion and [VOO(dipic)](2-phepyH)·H2O has higher antioxidant activity than L-ascorbic acid. Our studies confirmed that high basicity of the auxiliary ligand increases the reactivity of the complex with the superoxide radical. 相似文献
5.
《国际聚合物材料杂志》2012,61(14):1102-1114
A copolymer resin, p-chloroacetophenone oxime-furfuraldehyde (CAOFU), and a terpolymer resin, p-chloroacetophenone oxime-formaldehyde-benzoic acid (CAOFUBA), were synthesized in the presence of hydrochloric acid as catalyst. The structures of copolymer and terpolymer were established by FT-IR and 1H NMR techniques. Molecular weight and polydispersity index were determined by gel permeation chromatography. The thermal stability was evaluated by thermogravimetric analyses (TGA). Softening temperatures (Ts) of these polymers were obtained from differential scanning calorimetry (DSC). All the synthesized polymers have shown reasonably good antimicrobial activities. 相似文献
6.
Tomasz Kostrzewa Jakub Joczyk Joanna Drzedon Dagmara Jacewicz Magdalena Grska-Ponikowska Marcin Koaczkowski Alicja Kuban-Jankowska 《International journal of molecular sciences》2022,23(13)
One of the main goals of recent bioinorganic chemistry studies has been to design and synthesize novel substances to treat human diseases. The promising compounds are metal-based and metal ion binding components such as vanadium-based compounds. The potential anticancer action of vanadium-based compounds is one of area of investigation in this field. In this study, we present five oxovanadium(IV) and dioxovanadium(V) complexes as potential PTP1B inhibitors with anticancer activity against the MCF-7 breast cancer cell line, the triple negative MDA-MB-231 breast cancer cell line, and the human keratinocyte HaCaT cell line. We observed that all tested compounds were effective inhibitors of PTP1B, which correlates with anticancer activity. [VO(dipic)(dmbipy)]·2 H2O (Compound 4) and [VOO(dipic)](2-phepyH)·H2O (Compound 5) possessed the greatest inhibitory effect, with IC50 185.4 ± 9.8 and 167.2 ± 8.0 nM, respectively. To obtain a better understanding of the relationship between the structure of the examined compounds and their activity, we performed a computer simulation of their binding inside the active site of PTP1B. We observed a stronger binding of complexes containing dipicolinic acid with PTP1B. Based on our simulations, we suggested that the studied complexes exert their activity by stabilizing the WPD-loop in an open position and limiting access to the P-loop. 相似文献
7.
Dr. Sebastian Doniz Kettenmann Matthew White Julien Colard-Thomas Matilda Kraft Dr. Andrea T. Feßler Karin Danz Dr. Gerhard Wieland Dr. Sylvia Wagner Prof. Dr. Stefan Schwarz Dr. Arno Wiehe Prof. Dr. Nora Kulak 《ChemMedChem》2022,17(3):e202100702
Prodigiosenes are a family of red pigments with versatile biological activity. Their tripyrrolic core structure has been modified many times in order to manipulate the spectrum of activity. We have been looking systematically at prodigiosenes substituted at the C ring with alkyl chains of different lengths, in order to assess the relevance of this substituent in a context that has not been investigated before for these derivatives: Cu(II) complexation, DNA binding, self-activated DNA cleavage, photoinduced cytotoxicity and antimicrobial activity. Our results indicate that the hydrophobic substituent has a clear influence on the different aspects of their biological activity. The cytotoxicity study of the Cu(II) complexes of these prodigiosenes shows that they exhibit a strong cytotoxic effect towards the tested tumor cell lines. The Cu(II) complex of a prodigiosene lacking any alkyl chain excelled in its photoinduced anticancer activity, thus demonstrating the potential of prodigiosenes and their metal complexes for an application in photodynamic therapy (PDT). Two derivatives along with their Cu(II) complexes showed also antimicrobial activity against Staphylococcus aureus strains. 相似文献
8.
通过四氯化钛与酒石酸反应,制得了新的固态配合物Ti2O2(OH)2C4H4O6·3H2O。用元素分析、X-射线粉末衍射,IR和TG分析确定了产物的组成。TG和DSC研究了它在空气氛围下的热分解特性,计算机求解热分解反应各阶段的活化能Ea,反应级数n、焓变面△rH和熵变面△rS。在550℃灼烧1小时,可得锐钛型TiO2。 相似文献
9.
Rufen Zhang Yinfeng Han Chunlin Ma 《Journal of Inorganic and Organometallic Polymers and Materials》2006,16(1):25-29
A novel one-dimensional (1D) supramolecular dimethyltin compound of (Me2SnO)2(Me2SnOCH3)(O2CCH2SC4H3N2-2,6)[Me2Sn(O2CCH2SC4H3N2-2,6)2]·CH3OH was prepared by the reaction of (CH3)2SnCl2 with (2-pyrimidylthio)acetic acid with CH3ONa as a base. The title compound contained four different tin atom environments. Among them, Sn(1) and Sn(2) were both five-coordinate
with distorted trigonal bipyramidal geometries, Sn(3) was six-coordinate with a distorted octahedral geometry and Sn(4) was
seven-coordinate with pentagonal bipyramidal geometry. Meanwhile, the compound was stabilized in a 1D infinite chain by intermolecular
Sn–O bonds.
An erratum to this article can be found at 相似文献
10.
Karolina Stryjska Izabela Korona-Glowniak Lilianna Chciska Joachim Kusz Justyn Ochocki 《International journal of molecular sciences》2021,22(4)
In a previous article, we reported on the higher toxicity of silver(I) complexes of miconazole [Ag(MCZ)2NO3 (1)] and [Ag(MCZ)2ClO4 (2)] in HepG2 tumor cells compared to the corresponding salts of silver, miconazole and cisplatin. Here, we present the synthesis of two silver(I) complexes of miconazole containing two new counter ions in the form of Ag(MCZ)2X (MCZ = 1-[2-(2,4-dichlorobenzyloxy)-2-(2,4-dichlorophenyl)ethyl]-1H-imidazole]; X = BF4− (3), SbF6− (4)). The novel silver(I) complexes were characterized by elemental analysis, 1H NMR, 13C NMR and infrared (IR) spectroscopy, electrospray ionization (ESI)-MS spectrometry and X-ray-crystallography. In the present study, the antimicrobial activity of all obtained silver(I) complexes of miconazole against six strains of Gram-positive bacteria, five strains of Gram-negative bacteria and yeasts was evaluated. The results were compared with those of a silver sulfadiazine drug, the corresponding silver salts and the free ligand. Silver(I) complexes exhibited significant activity against Gram-positive bacteria, which was much better than that of silver sulfadiazine and silver salts. The highest antimicrobial activity was observed for the complex containing the nitrate counter ion. All Ag(I) complexes of miconazole resulted in much better inhibition of yeast growth than silver sulfadiazine, silver salts and miconazole. Moreover, the synthesized silver(I) complexes showed good or moderate activity against Gram-negative bacteria compared to the free ligand. 相似文献
11.
Thomas Eichhorn Franz Kolbe Stefan Mii Duan Dimi Ibrahim Morgan Mohamad Saoud Dejan Milenkovi Zoran Markovi Tobias Rüffer Jasmina Dimitri Markovi Goran N. Kaluerovi 《International journal of molecular sciences》2023,24(1)
Ruthenium(II)–arene complexes have gained significant research interest due to their possible application in cancer therapy. In this contribution two new complexes are described, namely [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]X (X = Cl, 1; PF6, 2), which were fully characterized by IR, NMR, and elemental microanalysis. Furthermore, the structure of 2 in the solid state was determined by a single crystal X-ray crystallographic study, confirming the composition of the crystals as 2·2MeOH. The Hirshfeld surface analysis was employed for the investigation of interactions that govern the crystal structure of 2·2MeOH. The structural data for 2 out of 2·2MeOH was used for the theoretical analysis of the cationic part [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]+ (2a) which is common to both 1 and 2. The density functional theory, at B3LYP/6-31+G(d,p) basis set for H, C, N, and Cl atoms and LanL2DZ for Ru ions, was used for the optimization of the 2a structure. The natural bond orbital and quantum theory of atoms in molecules analyses were employed to quantify the intramolecular interactions. The reproduction of experimental IR and NMR spectra proved the applicability of the chosen level of theory. The binding of 1 to bovine serum albumin was examined by spectrofluorimetry and molecular docking, with complementary results obtained. Compound 1 acted as a radical scavenger towards DPPH• and HO• radicals, along with high activity towards cancer prostate and colon cell lines. 相似文献
12.
ABSTRACTComplexation of Pu(IV) and Th(IV) cations by the title ligands – hydrophilic sulfophenyl triazinyl derivatives of bis-triazinyl-pyridine and -bipyridine – was studied in solvent extraction systems containing a TODGA extractant and one of these hydrophilic ligands. Stoichiometries and stability constants of the complexes formed in an acidic (HNO3) aqueous phase have been determined. The Pu(IV) complexes are significantly stronger than their Th(IV) analogues. Only two complexes of each metal with SO3-Ph-BTP (1:1 and 1:2) have been detected, and only one (1:1) with SO3-Ph-BTBP; both numbers being less than expected based on the coordination numbers of the metal ions and on the denticities of the ligands. Possible reasons of this discrepancy are discussed. 相似文献
13.
K. Jacinth Mispa R. Muthulakshmi C. Prathees Kumar P. Subramaniam R. Murugesan 《Polymer-Plastics Technology and Engineering》2017,56(1):55-70
The synthesized polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate composite ion exchangers were characterized by Fourier transform infrared spectroscopy, UV spectra, X-ray diffraction, scanning electron microscope, thermogravimetric analysis, and conductivity studies. The ion-exchange capacities, effect of eluent concentration, elution time, elution behavior, and pH on ion-exchange capacity were also studied to exploit the ion-exchange capability of the composites. The study revealed that polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate ion exchangers are having excellent ion-exchange capacity values for K+ ion 1.36 and 1.44?meq?g?1, respectively. The organic polymeric part of the composites provides mechanical and chemical stability, whereas the inorganic part supports the ion-exchange behavior and thermal stability. The increase in electrical conductivity is due to the inorganic and organic parts. A mechanism for the formation of the polyaniline-Zr(IV) selenoiodate and polyaniline-Zr(IV) selenomolybdate composite ion exchangers is discussed, which may also be applied for the preparation of other composite ion exchangers. Sorption behavior of metal ions on the composites was studied in different solvent systems. On the basis of distribution coefficient values (Kd), it has been found that the cation-exchange materials are highly selective for Pb(II)-ions. Such modified composite materials can be applied as an electrochemically switchable ion exchanger for water treatment, especially water softening. 相似文献
14.
Alexandra Mu?oz-Bonilla María L. Cerrada Marta Fernández-García Anna Kubacka Manuel Ferrer Marcos Fernández-García 《International journal of molecular sciences》2013,14(5):9249-9266
Nanocomposites obtained from the incorporation of synthesized TiO2 nanoparticles (≈10 nm average primary particle size) in different amounts, ranging from 0.5 to 5 wt.%, into a biodegradable polycaprolactone matrix are achieved via a straightforward and commercial melting processing. The resulting nanocomposites have been structurally and thermally characterized by transmission electron microscopy (TEM), wide/small angle X-ray diffraction (WAXS/SAXS, respectively) and differential scanning calorimetry (DSC). TEM evaluation provides evidence of an excellent nanometric dispersion of the oxide component in the polymeric matrix, with aggregates having an average size well below 100 nm. Presence of these TiO2 nanoparticles induces a nucleant effect during polymer crystallization. Moreover, the antimicrobial activity of nanocomposites has been tested using both UV and visible light against Gram-negative Escherichia coli bacteria and Gram-positive Staphylococcus aureus. The bactericidal behavior has been explained through the analysis of the material optical properties, with a key role played by the creation of new electronic states within the polymer-based nanocomposites. 相似文献
15.
Jatin N. Patel Mitul B. Dolia Kirit H. Patel Rajni M. Patel 《Journal of Polymer Research》2006,13(3):219-228
The methacrylate monomer 4-chloro-3‐methyl phenyl methacrylate (CMPM) was synthesized by reacting 4-chloro-3‐methyl phenol
with methacryloyl chloride. The homopolymer and various copolymers of CMPM with n-butyl methacrylate were synthesized by free-radical polymerization in toluene at 70°C using 2,2′-azobis(isobutyronitrile)
as the initiator. The CMPM monomer was characterized by Fourier transform IR and 1H-NMR studies. The copolymers were characterized by IR spectroscopy. The molecular weights (M
n and M
w) and the polydispersity index were obtained from gel permeation chromatography. The solubility and intrinsic viscosity of
the homopolymer and the copolymers are also discussed here. The copolymer composition obtained from UV spectra led to the
determination of reactivity ratios employing Fineman-Ross and Kelen-Tudos linearization methods. Thermogravimetric analyses
of the homopolymer and the copolymers were carried out under a nitrogen atmosphere. The homopolymer and the copolymers prepared
were tested for their antimicrobial activity against bacteria, fungi and yeasts. 相似文献
16.
Nonjabulo Prudence Gule Michele de Kwaadsteniet Thomas Eugene Cloete Bert Klumperman 《大分子材料与工程》2012,297(7):618-626
Antimicrobial poly(vinyl alcohol) nanofibres are produced using AquaQure biocide as additive to the polymer solution. AquaQure is an aqueous antimicrobial agent containing mainly Cu2+ and Zn2+. Antimicrobial tests show that the fibres achieve up to a 5 log reductions in populations of E. coli, S. aureus, S. typhimurium, P. aeruginosa and K. pneumoniae bacteria. Reusability of the nanofibre membranes is investigated to establish if the nanofibres retain their morphology and antimicrobial effectiveness over six cycles of water filtration. Leaching of AquaQure constituents from the nanofibres into filtered water is assessed and found to be at acceptable levels.
17.
A new method for the preparation of new heterocyclic amine surfactants based on sulfobetaines is proposed. Interfacial activities of the surfactants obtained in aqueous solution were studied by surface tension measurements. The critical micelle concentration, surface excess concentration, minimum area per surfactant molecule, and standard Gibbs energy of adsorption were determined. The adsorption properties of these compounds depend significantly on the alkyl chain length. Alkyl chain length also affects biological properties of the new surfactants, determining the minimum inhibitory concentration and size of inhibited growth zone. The compounds have high antimicrobial activity. 相似文献
18.
The hybrid material of EP‐POSS mixture was synthesized by the hydrolysis and condensation of (γ‐glycidoxypropyl) trimethoxysilane. A series of binary systems of EP‐POSS/epoxy blends, epoxy resin modified by silica nanoparticles (SiO2/epoxy), and ternary system of SiO2/EP‐POSS/epoxy nanocomposite were prepared. The dispersion of SiO2 in the matrices was evidenced by transmission electron micrograph, and the mechanical properties, that is, flexural strength, flexural modulus, and impact strength were examined for EP‐POSS/epoxy blends, SiO2/epoxy, and SiO2/EP‐POSS/epoxy, respectively. The fractured surface of the impact samples was observed by scanning electron micrograph. Thermogravimetry analysis were applied to investigate the different thermal stabilities of the binary system and ternary system by introducing EP‐POSS and SiO2 to epoxy resin. The results showed that the impact strength, flexural strength, and modulus of the SiO2/EP‐POSS/epoxy system increased around by 57.9, 14.1, and 44.0% compared with the pure epoxy resin, Ti, Tmax and the residues of the ternary system were 387°C, 426°C, and 25.2%, increased remarkably by 20°C, 11°C and 101.6% in contrast to the pure epoxy resin, which was also higher than the binary systems. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 810‐819, 2013 相似文献
19.
aneta Arciszewska Sofia Gama Monika Kalinowska Grzegorz
widerski Renata
wisocka Ewelina Gobiewska Monika Naumowicz Mateusz Worobiczuk Adam Cudowski Anna Pietryczuk Concetta De Stefano Demetrio Milea Wodzimierz Lewandowski Beata Godlewska-ykiewicz 《International journal of molecular sciences》2022,23(2)
Caffeic acid (CFA) is one of the various natural antioxidants and chemoprotective agents occurring in the human diet. In addition, its metal complexes play fundamental roles in biological systems. Nevertheless, research on the properties of CFA with lanthanide metals is very scarce, and little to no chemical or biological information is known about these particular systems. Most of their properties, including their biological activity and environmental impact, strictly depend on their structure, stability, and solution behaviour. In this work, a multi-analytical-technique approach was used to study these relationships for the Eu(III)/CFA complex. The synthesized metal complex was studied by FT-IR, FT-Raman, elemental, and thermal (TGA) analysis. In order to examine the chemical speciation of the Eu(III)/CFA system in an aqueous solution, several independent potentiometric and spectrophotometric UV-Vis titrations were performed at different M:L (metal:ligand) and pH ratios. The general molecular formula of the synthesized metal complex in the solid state was [Eu(CFA)3(H2O)3]∙2H2O (M:L ratio 1:3), while in aqueous solution the 1:1 species were observed at the optimum pH of 6 ≤ pH ≤ 10, ([Eu(CFA)] and [Eu(CFA)(OH)]−). These results were confirmed by 1H-NMR experiments and electrospray-ionization mass spectrometry (ESI-MS). To evaluate the interaction of Eu(III)/CFA and CFA alone with cell membranes, electrophoretic mobility assays were used. Various antioxidant tests have shown that Eu(III)/CFA exhibits lower antioxidant activity than the free CFA ligand. In addition, the antimicrobial properties of Eu(III)/CFA and CFA against Escherichia coli, Bacillus subtilis and Candida albicans were investigated by evaluation of the minimum inhibitory concentration (MIC). Eu(III)/CFA shows higher antibacterial activity against bacteria compared to CFA, which can be explained by the highly probable increased lipophilicity of the Eu(III) complex. 相似文献
20.
Mohamed S. El-Attar Sadeek A. Sadeek Sherif M. Abd El-Hamid Hazem S. Elshafie 《International journal of molecular sciences》2022,23(14)
Coumarin is highly distributed in nature, notably in higher plants. The biological features of coumarin include antibacterial, anticancer and antioxidant effects. It is well known that metal ions present in complexes accelerate the drug action and the efficacy of organic therapeutic agents. The main aim of the current study is the synthesis of different complexes of the interaction between ciprofloxacin hydrochloride (CIP) and coumarin derivative 7-hydroxy-4-methylcoumarin (HMC) with Zr(IV). The chelates of CIP with Zr(IV) were prepared and characterized by elemental analysis, melting point, conductance measurements, spectroscopic techniques involving IR, UV-Vis, 1H NMR, and thermal behavior (TG-DTG) in the presence of HMC, dimethylformamide (DMF), pyridine (Py), and triethylamine (Et3N). Results of molar conductivity tests showed that the new synthesized complexes are electrolytes with a 1:1 or 1:2 electrolyte ratio, with the chloride ions functioning as counter ions. According to IR spectra, CIP acts as a neutral bidentate ligand with Zr(IV) through one carboxylato oxygen and the carbonyl group, HMC as a monodentate through the carbonyl group, and DMF through the oxygen atom of the carbonyl group and the N atom of Py and Et3N. The thermal behavior of the complexes was carefully investigated using TG and DTG techniques. TG findings signal that water molecules are found as hydrated and coordinated. The thermal decomposition mechanisms proposed for CIP, HMC, and Zr(IV) complexes are discussed and the activation energies (Ea), Gibbs free energies (∆G*), entropies (∆S*), and enthalpies (∆H*) of thermal decomposition reactions have been calculated using Coats–Redfern (CR) and Horowitz–Metzeger (HM) methods. The studied complexes were tested against some human pathogens and phytopathogens, including three Gram-positive bacteria (Bacillus subtilis, B. cereus, Brevibacterium otitidis) and three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae), and compared to the free CIP and HMC parent compounds. 相似文献