Browsing by Author "Kandemirli, Fatma"

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Adsorption behavior and corrosion inhibitive characteristics of newly synthesized cyano-benzylidene xanthenes on copper/sodium hydroxide interface: Electrochemical, X-ray photoelectron spectroscopy and theoretical studies.
(2020-11-15T00:00:00Z) Khalifa, Mohamed E; El Azab, Islam H; Gobouri, Adil A; Mersal, Gaber A M; Alharthi, Sarah; Saracoglu, Murat; Kandemirli, Fatma; Ryl, Jacek; Amin, Mohammed A
Elegant process for synthesis of 3-(7H-dibenzo[c,h]xanthen-7-yl)benzaldehyde (3), as new starting material to create a set of novel xanthene analogues, 2-(3-(7H-dibenzo[c,h]xanthen-7-yl)benzylidene)malononitrile (4), 3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylic acid (5), and Ethyl-3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylate (6), was achieved starting with available materials under mild conditions. Various concentrations (ca. 0.1-1.0 mM) of the synthesized cyano-benzylidene xanthene derivatives, namely compounds 3-6, were tested as inhibitors to control copper corrosion in alkaline solutions employing polarization and electrochemical impedance spectroscopy (EIS) measurements. Results revealed that the four studied xanthenes derivatives served as efficient (mixed-type) inhibitors. The inhibition efficiency increased with increase in inhibitor concentration.The inhibition performance of studied compounds varied according to their chemical structures. The best inhibitor, compound (5), achieved a maximum inhibition efficiency of 98.7% (calculated from corrosion current densities) and ~ 95% (estimated from charge-transfer resistance values) at a concentration of 1.0 mM. The morphology of the corroded and inhibited copper surfaces was studied by scanning electron microscopy (SEM). The adsorption of the inhibitor molecules was confirmed by high-resolution X-ray photoelectron spectroscopy (XPS) profiles. XPS data were used to compare the inhibition efficiencies exhibited by studied compounds. The oxidation rate of the Cu surface was found to be frivolous, referring to high inhibition efficiency, only in the presence of inhibitor (5), and Cu share is 87% of all copper components. The shares of Cu were significantly reduced to 43%, 26% and 20% for inhibitors (3), (4) and (6), respectively. These findings go parallel with the results obtained from electrochemical measurements. The quantum-chemical calculations of the investigated molecules were performed to support electrochemical findings, and their correlations with the inhibition efficiency of the synthesized compounds were discussed.
Analysis of DNA protection, interaction and antimicrobial activity of isatin derivatives.
(2019-02-01T00:00:00Z) Ganim, Mohamed Abdulhamid; Baloglu, Mehmet Cengiz; Aygun, Aysenur; Altunoglu, Yasemin Celik; Sayiner, Hakan Sezgin; Kandemirli, Fatma; Sen, Fatih
Isatin, thiosemicarbazone and their derivatives have been widely used in biological applications such as antimicrobial, antiviral and anticancer therapies. Herein, eight isatin and thiosemicarbazone derivative compounds were re-synthesized and evaluated for DNA binding analysis including DNA protection studies using plasmid DNA (pUC19) and DNA interaction experiments using calf thymus DNA (CT-DNA). All compounds were also utilized in vitro assay to assess the antimicrobial activity of compounds against different pathogenic bacterial strains. All isatin and thiosemicarbazone derivative compounds exhibited DNA protection activity which ranged from 23.5 to 59.5%. Among them, I3-(N-2-MP)-TSC had the greatest DNA protective activity. For DNA binding analysis, all compounds had the same constant concentration (40 μM), which interacts with CT-DNA. It was also observed that DNA interactions gave a high intrinsic binding constant (Kb = 1.72 × 10 M-9.73 × 10 M). Besides, several derivatives of isatin thiosemicarbazone exhibited significant and selective antibacterial activity with low concentration. These compounds primarily affected Gram-positive bacteria, but were not effective against P. vulgaris and E. coli. The Gram-positive methicillin-resistant S. aureus ATCC 43300 (MRSA) was the most influenced strain by these compounds. It was found that methyphenyl group at isatin was essential for its antibacterial activity for MRSA.
Carbazochrome carbon nanotube as drug delivery nanocarrier for anti-bleeding drug: quantum chemical study.
(2021-12-20T00:00:00Z) Sayiner, Hakan S; Kandemirli, Fatma; Dalgic, Serap Senturk; Monajjemi, Majid; Mollaamin, Fatemeh
The interaction between drugs and single-walled carbon nanotubes is proving to be of fundamental interest for drug system of delivery and nano-bio-sensing. In this study, the interaction of pristine CNT with carbazochrome, an anti-hemorrhagic or hemostatic agent, was investigated with M06-2X functional and 6-31G basis set. All probable positions of related adsorption for these kind drugs were thought-out to find out which one is energetically suitable. Based on the achieved data, the stronger interactions appeared the oxygen atom of C = O group and nitrogen atom of imine groups. The topology analysis of QTAIM (quantum theory of atoms in a molecule) method was accomplished to understand the properties of interactions between the CNT and carbazochrome. Frontier molecular orbital energies of all systems, global index including stiffness, softness, chemical Gibbs energies, and electrophilicity parameters, as well as some other important physical data such as dipole moment, polarizability, anisotropy polarisibility, and hyperpolaribility were calculated, evaluated, and then compared together. The essence of the formed bonding model progress along the reaction roots was further validated using electron localization function (ELF) calculations. The highest values of adsorption energies were determined in the range of 18.24 up to 22.12 kcal mol for these kind systems. The acceptable recovery time of 849 s was obtained for the desorption of carbazochrome from the CNT surface under UV-light. The final results exhibit that carbazochrome can serve as a promising carrier and also as sensitive sensors in any kind of practical application.
Electronic-topological and neural network approaches to the structure- antimycobacterial activity relationships study on hydrazones derivatives.
(2014) Kandemirli, Fatma; Vurdu, Can Dogan; Basaran, Murat Alper; Sayiner, Hakan Sezgin; Shvets, Nathaly; Dimoglo, Anatholy; Kovalish, Vasyl; Polat, Turgay
That the implementation of Electronic-Topological Method and a variant of Feed Forward Neural Network (FFNN) called as the Associative Neural Network are applied to the compounds of Hydrazones derivatives have been employed in order to construct model which can be used in the prediction of antituberculosis activity. The supervised learning has been performed using (ASNN) and categorized correctly 84.4% of them, namely, 38 out of 45. Ph1 pharmacophore and Ph2 pharmacophore consisting of 6 and 7 atoms, respectively were found. Anti-pharmacophore features socalled "break of activity" have also been revealed, which means that APh1 is found in 22 inactive molecules. Statistical analyses have been carried out by using the descriptors, such as EHOMO, ELUMO, ΔE, hardness, softness, chemical potential, electrophilicity index, exact polarizibility, total of electronic and zero point energies, dipole moment as independent variables in order to account for the dependent variable called inhibition efficiency. Observing several complexities, namely, linearity, nonlinearity and multi-co linearity at the same time leads data to be modeled using two different techniques called multiple regression and Artificial Neural Networks (ANNs) after computing correlations among descriptors in order to compute QSAR. Computations resulting in determining some compounds with relatively high values of inhibition are presented.
Synthesis and characterization of new 1,3,4-thiadiazole derivatives: study of their antibacterial activity and CT-DNA binding.
(2022-10-17T00:00:00Z) Sayiner, Hakan S; Yilmazer, Mehmet I; Abdelsalam, Aisha T; Ganim, Mohamed A; Baloglu, Cengiz; Altunoglu, Yasemin Celik; Gür, Mahmut; Saracoglu, Murat; Attia, Mohamed S; Mahmoud, Safwat A; Mohamed, Ekram H; Boukherroub, Rabah; Al-Shaalan, Nora Hamad; Alharthi, Sarah; Kandemirli, Fatma; Amin, Mohammed A
1,3,4-Thiadiazole molecules (1-4) were synthesized by the reaction of phenylthiosemicarbazide and methoxy cinnamic acid molecules in the presence of phosphorus oxychloride, and characterized with UV, FT-IR, C-NMR, and H-NMR methods. DFT calculations (b3lyp/6-311++G(d,p)) were performed to investigate the structures' geometry and physiochemical properties. Their antibacterial activity was screened for various bacteria strains such as , ATCC 13048, , , , and Gram positive such as ATCC 25923, ATCC 7644, , , ATCC, , , , alfa , and found to have an inhibitory effect on and , while molecules 1, 3 and 4 had an inhibitory effect on and alpha . The experimental results were supported by the docking study using the Kinase ThiM from . All the investigated compounds showed an inhibitory effect for the protein. In addition, the mechanism of the 1-4 molecule interaction with calf thymus-DNA (CT-DNA) was investigated by UV-vis spectroscopic methods.
Synthesis and characterization of poly(3-hexylthiophene): improvement of regioregularity and energy band gap.
(2018-02-19T00:00:00Z) Ansari, Muhammad Azhar; Mohiuddin, Shaikh; Kandemirli, Fatma; Malik, Muhammad Imran
The organic solar cell (OSC) is a current hot topic in the context of energy related issues in order to capture energy in an economic and environmentally friendly manner from the most abundant natural source, the sun. However, the efficiency of OSCs achieved so far is not up to the mark. Major components of OSCs are the electron acceptor material, such as fullerene, and the electron donor material, such as poly(3-hexylthiophene), P3HT. Fullerene is an ideal acceptor material but molecular level engineering of P3HT is required to enhance the efficiency of OSCs. Optoelectronic properties of P3HT can be improved by controlling the regioregularity, energy band gap, and molar mass of the polymer. Additionally, p-doping of the semiconducting polymer can also help in broadening the optical spectrum of P3HT. In this study, we propose methods for the improvement of the above-mentioned properties during the synthesis of P3HT. The main focus was the improvement of the regioregularity of the synthesized P3HT, which was achieved by polymerization of 3-hexylthiophene under an electric field for the first time. The effect of molar mass and p-doping on the band gap is evaluated systematically and theoretical predictions are confirmed by experimental results.
Synthesis of Cyano-Benzylidene Xanthene Synthons Using a Diprotic Brønsted Acid Catalyst, and Their Application as Efficient Inhibitors of Aluminum Corrosion in Alkaline Solutions.
(2022-09-05T00:00:00Z) Amin, Mohammed A; Mersal, Gaber A M; El-Hendawy, Morad M; Shaltout, Abdallah A; Badawi, Ali; Boman, Johan; Gobouri, Adil A; Saracoglu, Murat; Kandemirli, Fatma; Boukherroub, Rabah; Ryl, Jacek; Khalifa, Mohamed E
Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene-aldehyde compound. Different xanthene concentrations (ca. 0.1-2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds' adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced.
The Quantum Chemical and QSAR Studies on Acinetobacter Baumannii Oxphos Inhibitors.
(2018-04-07) Sayiner, Hakan Sezgin; Abdalrahm, Afaf A S; Basaran, Murat A; Kovalishyn, Vasyl; Kandemirli, Fatma
Acinetobacter is a Gram-negative, catalase-positive, oxidase-negative, non-motile, and no fermenting bacteria.