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Öğe Approximation of the set of integrable trajectories of the control system with $L_2$ norm constraints on control functions(American Institute of Mathematical Sciences, June 2024) Nesir Huseyin; Anar Huseyin; Khalik G. GuseinovIn this paper an approximation of the set of multivariable and $L_2$ integrable trajectories of the control system described by Urysohn type integral equation is considered. It is assumed that the system is affine with respect to the control vector. The admissible control functions are chosen from the closed ball of the space $L_2$, centered at the origin with radius $\rho$. The set of admissible control functions is replaced, step by step, by the set of controls consisting of a finite number of piecewise-constant control functions. It is proved that under appropriate choosing of the discretization parameters, the set of trajectories generated by a finite number of piecewise-constant control functions is an internal approximation of the set of trajectories.Öğe Pyrimidine and cumene derivatives functionalized by hydroxy and methoxy: Computational insights in drug-likeness, ADM, and toxicity studies(Elsevier, 2023) Goncagül SerdaroğluThe –OH and –OCH3 functionalized isopropyl cumene and isopropyl pyrimidine derivatives were designed and, explored in terms of the ADM, and possible toxic effects in view of the medicinal and environmental. For this goal, the geometry optimizations and structural confirmations were conducted by the G09W package at B3LYP/ 6-311G** level of theory. The verified geometries were used for further computations and analyses. The bioavailability features such as lipophilicity, water solubility, and drug-likeness, pharmacokinetics were determined by SwissADME tools. Also, ADMETLab computations were used to predict the absorption, distribution, metabolism, and toxicity of the data set. The FMO and NBO analyses were performed to determine the –OH and –OCH3 function effect on the cumene and pyridine structures and then the electronic properties underlying the bioavailability and toxicity properties. Accordingly, the –OCH3 function on the structure l seems to be important to rise the inhibitory or substrate potency in the enzyme metabolism for both series. For the pyrimidine series, the anomeric interactions (n → σ*) in addition to the resonance interactions (n → π* and π → π*) also would have a role in molecular stability and affect the charge distribution on the molecular surface, which could play of remarkable role in the bioavailability and ADM. In terms of electronic structure and physicochemical properties, and possible bioactivity or toxicity relationship, the results obtained in the study will be an important reference source for the research on exploring/developing/improving future biocompatible molecular structures.Öğe Computational Insights in Drug-likeness and ADMT Properties of -dienes Resemble of Geranial(Dergipark, 2023) Goncagül SerdaroğluThis research aims to analyze the drug development potential of geranial, a naturally occurring compound known for its medicinal properties, through in-depth ADMT (Absorption, Distribution, Metabolism, and Toxicity) profiling and Density Functional Theory (DFT) calculations, at B3LYP/6-311G** level and basis set. The optimized and confirmed structures of the data set were used for further computations. The FMO "Frontier Molecular Orbital" energies and MEP "Molecular Electrostatic Potential" were considered to elucidate the possible reactivity features and regions of the molecules, respectively. Concurrently, DFT calculations helped to elucidate the compound's electronic properties and structural stability, further affirming its suitability for drug development. These findings emphasize the potential of compounds structurally related to geranial in the pharmaceutical field and underline the necessity of similar evaluations for novel drug candidates, ensuring safety and efficacy while mitigating potential risks to human health and the environment.Öğe Molecular modeling study on the water-electrode surface interaction in hydrovoltaic energy(Nature, 2023) Goncagül SerdaroğluThe global energy problem caused by the decrease in fossil fuel sources, which have negative effects on human health and the environment, has made it necessary to research alternative energy sources. Renewable energy sources are more advantageous than fossil fuels because they are unlimited in quantity, do not cause great harm to the environment, are safe, and create economic value by reducing foreign dependency because they are obtained from natural resources. With nanotechnology, which enables the development of different technologies to meet energy needs, low-cost and environmentally friendly systems with high energy conversion efficiency are developed. Renewable energy production studies have focused on the development of hydrovoltaic technologies, in which electrical energy is produced by making use of the evaporation of natural water, which is the most abundant in the world. By using nanomaterials such as graphene, carbon nanoparticles, carbon nanotubes, and conductive polymers, hydrovoltaic technology provides systems with high energy conversion performance and low cost, which can directly convert the thermal energy resulting from the evaporation of water into electrical energy. The effect of the presence of water on the generation of energy via the interactions between the ion(s) and the liquid–solid surface can be enlightened by the mechanism of the hydovoltaic effect. Here, we simply try to get some tricky information underlying the hydrovoltaic effect by using DFT/B3LYP/6-311G(d, p) computations. Namely, the physicochemical and electronic properties of the graphene surface with a water molecule were investigated, and how/how much these quantities (or parameters) changed in case of the water molecule contained an equal number of charges were analyzed. In these computations, an excess of both positive charge and negative charge, and also a neutral environment was considered by using the Na+, Cl−, and NaCl salt, respectively.Öğe Copper(II) chelates derived from an N,N,O-tridentate 2-pyridinecarboxaldehyde-N4-phenylsemicarbazone: Synthesis, spectral aspects, crystal structure, FMO and NBO analysis(Elsevier, 2023) Goncagül SerdaroğluSeven novel Cu(II) complexes [Cu(HPySc)Cl2] (1), [Cu2(PySc)2(NO3)2]·H2O (2), [Cu(HPySc)(SO4)]·½H2O (3), [Cu2(PySc)2(OAc)2]·CH3OH (4), [Cu2(PySc)2Br2]·H2O (5), [Cu(PySc)(NCS)]·2H2O (6) and [Cu2(PySc)2(N3)2] (7) with 2-pyridinecarboxaldehyde-N4-phenylsemicarbazone (HPySc) have been prepared and characterized using different analytical and spectroscopic techniques. The complex 6 is expected to be square planar while the other complexes are expected to be square pyramidal arrangement, among these, the geometry of complex 4 has been conformed by single crystal XRD study that it is a dimer and adopts distorted square pyramidal geometry around copper(II) centre. All the complexes are found to be paramagnetic and non-conductive in nature. The semicarbazone ligand is coordinated in neutral form in two of the complexes and in ionic form in others. DFT/B3LYP/6-311g**/LANL2DZ computations of the ligand HpySc (PyCHNNCONHPh) and seven Cu(II) complexes were performed to analyze the FMOs and important electron delocalizations that existed in each compound. Molecular stability and bond strengths have been investigated by applying natural bond orbital (NBO) analysis. All the complexes are more stable than the semicarbazone and the complex 2 is the most electronically stable (-5.160 eV) among the complexes. Furthermore, the semicarbazone is the hardest and complex 5 is the softest than all complexes due to the η values. The calculated energy gap between HOMO and LUMO energies show the variations of nucleophilic and electrophilic reactivity regions in the semicarbazone and in complexes 1-7.Öğe A novel series of tetrahydrothieno[2,3-c]pyridin-2-yl derivatives: fluorescence spectroscopy and BSA binding, ADMET properties, molecular docking, and DFT studies(RSC Publishing, 2023) Goncagül SerdaroğluIn this study, a series of substituted tetrahydrothieno[2,3-c]pyridin-2-yl (THTP) derivatives, i.e., C1–C3 and N1–N3, was synthesized in one step using 2-amino-5,5,7,7-tetramethyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carbonitrile with two different adjacent chloro- and nitro-substituted groups. Specifically, with a nitrile group on the thiophene structure, six new THTP (C1–C3 and N1–N3)-bearing electron-donating-electron-withdrawing moieties were designed with various pharmacological properties. For the first time in the literature, the synthesis of these target pharmaceutical products was carried out in less steps with high efficiency. Specifically, the notable features of this protocol are its simplicity and high reaction yields. Furthermore, spectroscopic methods were used to verify the structures of all the synthesized compounds (FT-IR, UV, 1H NMR, and 13C NMR). Additionally, the binding properties of the molecules with serum albumin were analyzed as a function of concentration and temperature and in the presence of Mg2+, Zn2+, and Ca2+. Moreover, molecular docking calculations were performed against bovine serum albumin, human leukemia inhibitory factor, and DNA. Also, DFT and TD-DFT computational studies were performed at the B3LYP/6-311G** level for structural and spectroscopic confirmation of compounds C1–C3 and N1–N3, and their possible reactivity features were evaluated via FMO “frontier molecular orbital” and NBO “natural bond orbital” analyses. Further, their physicochemical properties such as lipophilicity and water solubility, in addition to ADMET properties were estimated and evaluated. Considering the results obtained from the experiments and computations, it is hoped that this work will be a useful guide for future research on drug design.Öğe Substituted naphthoxy-phthalonitrile derivatives: Synthesis, substituent effects, DFT, TD-DFT Calculations, antimicrobial properties and DNA interaction studies(Elsevier, 2023) Goncagül SerdaroğluHerein, substituted-naphthol derivatives 4a–e were synthesized in two steps, namely the Diels Alder cycloaddition and Cu-catalyzed aromatization reactions, respectively. Then, pththalonitrile derivatives 7–12 have been prepared by a nucleophilic displacement reaction of 3-nitrophthalonitrile with the naphthol derivatives 4a-e, 5 and, obtained in excellent yields. Structural characterization of the compounds was identified by different spectroscopic techniques. Antimicrobial properties of the synthesized compounds were determined by the microdilution procedure against Gram-positive, Gram-negative bacteria, and yeast. Furthermore, the DNA interaction of the compounds were determined by gel electrophoresis. One of the most prominent findings is that compounds 9 and 10 have more inhibitory effects on Gram-positive bacteria than Gram-negative bacteria. These compounds especially exhibited the highest antibacterial potency against S. aureus (625 µg/mL) among Gram-positive bacteria. According to the plasmid DNA interaction results, the synthesized compounds caused changes in the structure and mobility of the plasmid DNA. Then, geometry optimizations and frequency calculations were conducted at B3LYP/6–311 G(d,p) level of DFT, and optimized structures were used for further analyses. The NBO results revealed that the π→π * and n→π * interactions were greatly contributed to lowering the stabilization energy of all compounds (7–12). FMO energy analyses showed that compound 9 has the biggest electrodonating power.Öğe Physicochemical properties, drug likeness, ADMET, DFT studies, and in vitro antioxidant activity of oxindole derivatives(Elsevier, 2023) Goncagül SerdaroğluPoor pharmacokinetic and safety profiles create significant hurdles in the drug development process. This work focuses on a detailed understanding of drug discovery interplay among physicochemical, pharmacokinetic, toxicity endpoints, and antioxidant properties of oxindole derivatives. DFT compıutations were also performed at B3LYP/6-311G** level to evaluate the physicochemical properties, global reactivity features, and intramolecular interactions. The BOILED-Egg pharmacokinetic model envisaged gastrointestinal absorption, blood-brain barrier penetration, and no interaction with p-glycoprotein for compounds C1 and C2. The physicochemical evaluation revealed that C1 possesses superior drug-like properties fit for oral absorption. Both derivatives were predicted to have high plasma protein binding, efficient distribution, and inhibiting CYP 450 major isoforms but serve as substrates only for a few of them. Both molecules have mild to moderate clearance rates. Out of ten toxicity parameters, only hepatotoxicity was predicted. DFT results implied that the meta position of the -OH group made the possibility of charge transfer greater than -para positioned -OH, due to the ΔNmax (eV) values of molecules C1 and C2 being calculated at 2.596 and 2.477, respectively. Both C1 and C2 exhibited a concentration dependant DPPH and ABTS radical scavenging activity. The chemical structure-physicochemical-pharmacokinetic relationship identified the meta position as the favorite for the electron-withdrawing hydroxyl group. This provides useful insight to medicinal chemists to design 6-chlorooxindole derivatives with an acceptable drug-like and pharmacokinetic property.Öğe In Silico, SwissADME, and DFT Studies of Newly Synthesized Oxindole Derivatives Followed by Antioxidant Studies(Hindawi, 2023) Goncagül SerdaroğluThe compounds were synthesized by refluxing 6-chlorooxindole with 2,3-dichlorobenzaldehyde and 2,6-dichlorobenzaldehyde in the presence of piperidine as a catalyst and characterized by spectroscopic analysis using 1H NMR, 13C NMR, and mass spectrometry as (E)-3-(2,3-dichlorobenzylidene)-6-chloroindolin-2-one (C-1) and (E)-3-(2,6-dichlorobenzylidene)-6-chloroindolin-2-one (C-2). Additionally, in silico ADME studies indicated that C-1 and C-2 with 1,1 rotatable bonds could have moderate water solubility and therefore could have the potential ability to cross the blood-brain barrier. Both showed high GI absorption, indicating that they are suitable for intestinal absorption while the compounds showed CYP1A2, CYP2C19, and CYP2C9 inhibition. The five drug-likeness criteria, which were Lipinski, Muegge, Ghose, Veber, and Egan, and the principles of drug-likeness are not violated by compounds C-1 and C-2. Also, the DFT computations were performed at the B3LYP level and at 6-311++G basis set to evaluate and support the obtained results from the experiment. The FMO results revealed that C-1 could likely prefer the intramolecular interactions rather than the intermolecular interactions, and vice versa for C-2. In addition, the NBO results indicated that the resonance interaction, especially the shift of electron to empty orbitals from lone pair electrons of nitrogen, would contribute to the stabilization of both compounds greatly. In DPPH assay, the compounds showed IC50 values of 37.390 and 34.676 μM, respectively. Similarly, in ABTS assay, the calculated IC50 values for the compounds were 25.381 and 33.706 μM, respectively. In short, these results provided a solid ground for further preclinical studies in quest of new effective therapeutic agents.Öğe An efficient new method of ytterbium(III) triflate catalysis approach to the synthesis of substituted pyrroles: DFT, ADMET, and molecular docking investigations(Elsevier, 2023) Goncagül SerdaroğluIn this study, the one-pot synthetic methodology for the preparation of substituted pyrroles with diethyl acetylene-dicarboxylate is reported for the various pyrrole derivatives via the Trifimow synthesis process from oximes. This method also offers the literature as a cyclization pathway using a ytterbium triflate catalyst. Another importance of this study is the use of pyrrole derivatives in pharmaceuticals, biological processes, and agrochemicals. From this point of view, the development of a new catalyst in synthetic organic chemistry and the difference in the method is also important. The syntheses of the target substituted pyrroles are accomplished in high yields. Also, all synthesized structures were confirmed by 1H NMR, 13C NMR, and IR spectra. The DFT computations were leveraged for structural and spectroscopic validation of the compounds. Then, FMO and NBO analyses were subsequently employed to elucidate the reactivity characteristics and intramolecular interactions within these compounds. Also, ADMET indices were ascertained to assess potential pharmacokinetic properties, drug-like qualities, and possible adverse effects of these compounds. Last, optimized molecules were analyzed by molecular docking methods against crystal structures of Bovine Serum Albumin and Leukemia Inhibitory Factor, and their binding affinities, interaction details, and inhibition constants were determined.Öğe Efficient synthesis of chromeno[2,3-b]pyridine derivatives using Zn (OTf)2 as a catalyst: DFT computations, molecular docking and ADME Studies(Elsevier, 2023) Goncagül SerdaroğluAn efficient method was developed for the synthesis of chromeno[2,3-b]pyridine derivatives by using Zn(OTf)2 (Zinc trifluoromethanesulfonate) via one-pot [3 + 3] cascade annulation methods using 2-amino-4H-chromen-4-one with a different substituted group (1–6) and trans-chalcone. This strategy offers the pharmacological importance of 2-amino-4H-chromen-4-one derivatives in reaction time and good yields. This approach also brings a different perspective to the literature as an intramolecular cyclization pathway. All computational works were performed at the B3LYP/6–311++G** level of theory. After confirming the optimized structures and comparing the calculated spectroscopic data with corresponding experimental data, the intramolecular interactions were evaluated on the basis of NBO “Natural Bond Orbital” theory. The quantum chemical reactivity features and FMO “Frontier Molecular Orbital” analyses were conducted at the same level of theory. The solvent effect on the reactivity behaviors was also investigated by using the results that were determined by obtaining the different solvent environments. Molecular docking was employed to explore the binding affinities of the compounds against AChE (Acetylcholinesterase), BuChE (Butyrylcholinesterase), and HSA (Human serum albümin). Also, the bioavailability and drug-likeness properties of compounds 1–6 were determined to explore the possible usage in further drug design works.Öğe Nitrobenzamido substitution on thiophene-3-carboxylate: Electrochemical investigation, antioxidant activity, molecular docking, DFT calculations(Elsevier, 2023) Goncagül SerdaroğluA novel nitro containing thiophene derivatives containing have been synthesized. In pharmaceutical chemistry, thiophene derivatives show a biological effect. Due to the promising antimicrobial, analgesic and anti-inflammatory, and antitumor activity, alternative and different approaches have also been one of the main objectives in the field of chemical sciences. Based on the broad range of biological properties of thiophene derivatives, this study aimed to evaluate the antioxidant activity of novel thiophene derivatives and explore the electrochemical features using CV (cyclic voltammetry). The synthesis and characterization of novel benzo[b]thiophone derivatives were confirmed using spectroscopic methods with 1H-NMR, 13C-NMR, FT-IR, and UV-vis. The DFT and TD-DFT computations were conducted to compare the spectroscopic data and then confirm the molecular structures of the compounds 1-3. The FMO and NBO analyses were conducted to estimate the possible reactivity features and key intra-molecular interactions. Last, molecular docking investigations were performed to explore the possible interaction of each compound to human EGFR Kinase.Öğe Synthesis, antimicrobial activity and molecular docking study of benzyl functionalized benzimidazole silver(I) complexes(2023) Arı, Erkan; Şahin, Neslihan; Üstün, Elvan; Dündar, Muhammed; Karcı, Hüseyin; Özdemir, İlknur; Koç, Ahmet; Gürbüz, Nevin; Özdemir, İsmailIn this study, a series of N-functionalized benzimidazole silver(I) complexes were prepared and characterized by FT-IR, 1H, 13C{1H} NMR spectroscopy, and elemental analysis. Synthesized N-benzylbenzimidazole silver(I) complexes were evaluated for their antimicrobial activities against bacteria Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and the fungal strains Candida albicans and Candida glabrata. The results indicated that N-alkylbenzimidazole silver(I) complexes exhibited good antimicrobial activity compared to N-alkylbenzimidazole derivatives. Especially, complex 2e presented perfect antimicrobial activity than the other complexes. The characterized molecules were optimized by DFT-based calculation methods and the optimized molecules were analyzed in detail by molecular docking methods against bacterial DNA-gyrase and CYP51. The amino acid residues detected for both target molecules are consistent with expectations, and the calculated binding affinities and inhibition constants are promising for further studies.Öğe Interaction analysis of a new NHC precursor and its Ag-NHC complex with bovine serum albumin by spectrophotometric and molecular docking methods(2023) Üstün, Elvan; Şahin, NeslihanPotential bioactive molecules must reach the target tissue safely and serum albumin, which is a well-known major component in human blood, is an efficient transporter. Therefore, the interactions of possible bioactive species with serum albumin must be determined. In the current study, an N-heterocyclic carbene precursor and its silver complex were synthesized, characterized, and analyzed for interactions with bovine serum albumin. Stern- Volmer constant was recorded as 4.50105 for Ag-NHC with a 1.255 binding number at 298 K. Also, the molecules have spontaneously interacted with bovine serum albumin with a negative DG value (−32.93 kJ mol−1) for the complex at 298 K. Additionally, the effects of Ca2þ, Mg2þ, and Zn2þ on binding properties were evaluated by fluorescence spectroscopy. The binding constant of the complex was recorded as 6.76103 in the presence of Zn2þ and 5.93105 without the metals. The molecules were optimized by DFT-based calculations and the details of the bindings were investigated by molecular docking methods. Ag-NHC has interacted with the IIA subdomain region of bovine serum albumin with −8.46 kcal/mol.Öğe Benzimidazol-2-ylidene Silver Complexes: Synthesis, Characterization, Antimicrobial and Antibiofilm Activities, Molecular Docking and Theoretical Investigations(2023) Tutar, Uğur; Çelik, Cem; Üstün, Elvan; Özdemir, Namık; Şahin, Neslihan; Semeril, David; Gürbüz, Nevin; Özdemir, İsmailFive silver(I) complexes, namely chloro[1-methallyl-3-benzyl)benzimidazol-2-ylidene] silver (6), chloro[1-methallyl-3-(2,3,5,6-tetramethylbenzyl)benzimidazol-2-ylidene]silver (7), chloro[1- methallyl-3-(3,4,5-trimethoxylbenzyl)benzimidazol-2-ylidene]silver (8), chloro[1-methallyl- 3- (naphthylmethyl)benzimidazol-2-ylidene]silver (9), and chloro [1-methallyl-3-(anthracen-9-ylmethyl) benzimidazol-2-ylidene]silver (10), were prepared starting from their corresponding benzimidazolium salts and silver oxide in 71–81% yields. A single-crystal X-ray structure of 7 was determined. These five Ag-NHC complexes were evaluated for their antimicrobial and biofilm formation inhibition properties. Complex 10 exhibited high antimicrobial activities comparable to those obtained with standard drugs such as Fluconazole in contact with Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Acinetobacter baumannii, and Candida albicans. The latter complex has been shown to be very efficient in antibiofilm activity, with 92.9% biofilm inhibition at 1.9 g/mL on Escherichia coli. Additionally, the molecules were optimized with DFT-based computational methods for obtaining insight into the structure/reactivity relations through the relative energies of the frontier orbitals. The optimized molecules were also analyzed by molecular docking method against DNA gyrase of Escherichia coli and CYP51 from Candida albicans.Öğe Antimicrobial activities of bis-(N-alkylbenzimidazole)-cobalt(II) and zinc (II) complexes(2023) Şahin, Neslihan; Üstün, Elvan; Özdemir, İlknur; Günal, Selami; Özdemir, Namık; Bülbül, Hakan; Gürbüz, Nevin; Özdemir, İsmail; Semeril, DavidEight benzimidazole precursors (L), namely 1-allyl-benzimidazole, 1-methallyl-benzimidazole, 1-isopropyl-benzimidazole, 1-(3-methyloxetan-3-yl)methyl-benzimidazole, 1-allyl-5,6-dimethyl-benzimidazole, 1-methallyl-5,6- dimethyl-benzimidazole, 1-isopropyl-5,6-dimethyl-benzimidazole and 1-(3-methyloxetan-3-yl)methyl-5,6- dimethyl-benzimidazole, were coordinated to cobalt(II) and zinc(II) cations to form complexes of the type [MCl2L2]. Single-crystal X-ray structures were determined for two cobalt(II) and for one zinc(II) complexes and confirmed their tetrahedral molecular geometry. The antibacterial and antifungal activities of these two series of cobalt(II) and zinc(II) complexes were studied against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae), Gram-positive (Staphylococcus aureus, methicillin-resistant S. aureus and Enterococcus faecalis) bacteria and fungal strains (Candida albicans and Candida glabrata). Overall, cobalt(II) complexes were more effective than the zinc(II) complexes against all microorganisms. The most significant results were obtained with the two dichloro-bis(1-allyl-5,6-dimethylbenzimidazole)-cobalt(II) and dichloro-bis(1-methallyl-5,6-dimethylbenzimidazole)-cobalt(II) complexes against Candida albicans and Candida glabrata fungi with measured minimal inhibitory concentrations as low as 0.024 μmol/mL, values close to those obtained with the commercially available drug Flucanozole (0.020 μmol/mL).Öğe Design, synthesis, antimicrobial activity and molecular docking study of cationic bis?benzimidazole?silver(I) complexes(2023) Üstün, Elvan; Şahin, Neslihan; Özdemir, İlknur; Günal, Selami; Gürbüz, Nevin; Özdemir, İsmail; Semeril, DavidTwo series of bis(1‐alkylbenzimidazole)silver(I) nitrate and bis(1‐alkyl‐5,6‐ dimethylbenzimidazole)silver(I) nitrate complexes, in which the alkyl substituent is either an allyl, a 2‐methylallyl, an isopropyl or a 3‐methyloxetan‐3‐yl‐methyl chain, were synthesized and fully characterized. The eight N‐coordinated silver(I) complexes were screened for both antimicrobial activities against Gram‐negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii) and Gram‐positive (Staphylococcus aureus, Staphylococcus aureus MRSA, and Enterococcus faecalis) bacteria and antifungal activities against Candida albicans and Candida glabrata strains. Moderate minimal inhibitory concentrations (MIC) of 0.087 μmol/mL were found when the Gram‐negative and Gram‐positive bacteria were treated with the silver complexes. Nevertheless, MIC values of 0.011 μmol/mL, twice lower than for the well‐known fluconazole, against the two fungi were measured. In addition, molecular docking was carried out with the structure of Escherichia coli DNA gyrase and CYP51 from the pathogen Candida glabrata with the eight organometallic complexes, and molecular reactivity descriptors were calculated with the density functional theory‐based calculation methods.Öğe Metal cations toxicity: An inorganic interpretation(Published by Elsevier B.V., 2023-01) Elik, MustafaChemical hardness is one of the useful parameters giving information about the toxic nature of the structures. In the present work, absolute chemical hardness imparted to the science by Pearson, the hydration enthalpies, the element’s electronegativity, as calculated by Batsanov (using the force constants of the bonds), the calculated electrostatic charge on the hydrated cations, the absolute radii for the metals and the effective nuclear charges, were correlated with available toxicology data for a series of metal cations (namely Hg2+, Cd2+, Cu2+ and K+) in order to obtain, from a physicochemical point of view, a better understanding of the deleterious actions of metal cations on living organisms. A series of linear curves and empirical equations were obtained, providing a convincing picture of the correlation toxicity-physical inorganic chemistryÖğe Theoretical analysis of OLED performances of some aromatic nitrogen-containing ligands(Turkish Journal of Chemistry, 25.08.2023) Elik, MustafaThe recent work has an aim to establish a pivotal role of orbital exponent in the normalized atomic radii, atomic density and atomic hardness. These three periodic descriptors help to understand the real scenario of an element. Concerning the effective nuclear charge, screening constant and effective principal quantum number, we have developed a new relation between these periodic properties and invoked a new formula by which we can compute the normalized radii, density and global atomic hardness in terms of the orbital exponent. With comparison to the existing famous formulae originating from different concepts, we can conclude that our empirical computation has an inherent efficacy to predict periodicity.Öğe DYNAMICAL COMPLEXITIES IN A DISCRETE-TIME PREDATOR-PREY SYSTEM AS CONSEQUENCES OF THE WEAK ALLEE EFFECT ON PREY(2023) KANGALGİL,Figen; Işık, SevalIn this paper, a two dimensional discrete-time predator-prey system with weak Allee effect, affecting the prey population, is considered. The existence of the positive fixed points of the system and topological classification of coexistence positive fixed point are examined. By using the bifurcation theory, it is shown that the discrete-time predator-prey system with Allee effect undergoes flip and Neimark-Sacker bifurcations depending on the parameter a. The parametric conditions for existence and direction of bifurcations are investigated. Numerical simulations including bifurcation diagrams, phase portraits and maximum Lyapunov exponents of the system are performed to validate analytical results. The computation of the maximum Lyapunov exponents confirm the presence of chaotic behaviour in the considered system. Finally,the OGY feedback control method is implemented to stabilize chaos existing in the system
