Antibacterial potential of N-(2-furylmethylidene)-1, 3, 4-thiadiazole-2-amine: Experimental and theoretical investigations

Recently, a lot of interest has been attributed to the Schiff base compound because of its wide range of biological activities which include: antibacterial, antifungal, antima larial, including; antiproliferative, antiviral, and antipyretic. In this research work, N-(2-furylmethylidene)-1, 3, 4-thiadiazole- 2-amine gotten from o-phenylenediamine and 5- methoxysalicaldehyde was produced and characterized using UV–Visible, FT-IR, ¹H NMR, ¹³C NMR, and GC-MS along with molecular modeling using density functional theory (DFT) and molecular docking approach. The results obtained indicated that the Schiff base exhibited antimicrobial action against all the tested microbes except Candidaalbicans isolate, which exhibited zero diameter zone of inhibition. The theoretical investigations of the synthesized compounds were computed applying density functional theory at the B3LYP/6–31++G (d, p) level of theory and in silico molecular docking simulation. In comparing binding affinity energies and binding poses of the studied compound and the standard drug (ampicillin), the deduction that the molecular docking analysis results are in good agreement with in vitro analysis of the synthesized compounds can be made.     

Antimicrobial activities of 1-phenyl-3-methyl-4-trichloroacetyl-pyrazolone: Experimental,DFT studies,and molecular docking investigation

The rate of bacterial resistance to antibiotics is faster than the rate of discovery of new antibiotic classes. However, development of novel compounds with similar behavior but with a better therapeutic action has posed a serious challenge to researchers. Therefore, discovering of new novel drugs is of great importance in combating health problems and improving the quality of human life. In this research, first principle density functional theory (DFT) along with molecular docking approach were utilized for the investigation of 1-phenyl-3-methyl-4-trichloroacetyl-pyrazolone-5 (HTcP) to address some factors that are linked to this phenomenon. The theoretical computations were carried out utilizing the Becke-3-Parameter-hybrid model of Lee-Yang-Parr (B3LYP) with the 6-31+G (d, p) basis set. The most active site of the studied compound was studied within the framework of molecular electrostatic potential (ESP) meanwhile the strength and nature of the bond was studied using quantum theory of atoms in molecules (QTAIM). The antibacterial activities of the title structure was tested in this study using three proteins, 4YNT, 4YNU, and 5UZ9, with the help of Bio – via discovery studio and Auto dock vina tool via molecular docking simulations. The compound had a higher binding energy with the 4YNT and 4YNU proteins (?7.7 kcal/mol). Also controlled model was used in the docking analysis which shows no much significant different between the modelled structure and the commercial drug Kanamycin. In addition, a computer simulation was used to predict the absorption, distribution, metabolism, excretion, and toxicity profiles of the compound under investigation (ADMET). The result obtained from the ADMET studies indicated that the structure under study has moderate antibacterial activities.     

Spectroscopic,conformational analysis,structural benchmarking,excited state dynamics,and the photovoltaic properties of Enalapril and Lisinopril

There have been numerous attempts to theoretically design a better photovoltaic property with much interest on how to improved absorption and emission parameters of most reactive compounds in respect to dye – sensitized solar cells (DSSCs). This is regardless of the promising futures of the photovoltaic properties. However, for such effective design, it is necessary to understand the electronic and photophysical properties of the dye systems. Herein detailed density functional theory (DFT) and time – dependent DFT (TD-DFT) investigation of the excited state characteristics and the influence of various solvents: water, acetone, ethanol and chloroform on the photophysical properties of enalapril and lisinopril were investigated along with the experimental spectral (UV–vis and FT-IR) analysis. The electronic structure calculations were conducted using the 6–311++G(d,p) basis set in combination with B3LYP, M06-2X, and ?B97XD DFT functionals for the structural benchmarking investigations of the studied compounds. Results of the excitation electronic analysis of enalapril was observed to have wavelength absorption in the order gas > chloroform > ethanol > water which correspond to 229.19, 228.81, 228.85, 229.03 nm respectively while Lisinopril have the order of chloroform > gas > water > ethanol which present ethanol have the highest transition energy. In all the studied structured, the transition assignment corresponds to π $\to$ π* all corresponding to the Frank -Condon local excitation. It can be inferred from the photovoltaic properties that among the studied compounds in four different phases enalapril have the highest oscillator strength, but the values of light-harvesting efficiency (LHE) varies and show greater stability in Lisinopril. Lisinopril was observed to have the highest value of $V_{OC}$ compared to Enalapril this further confirmed the result obtained from the frontier molecular orbitals.     

Computational Study on Interactions between CO2 and (TiO2)n Clusters at Specific Sites

The energetic pathways of adsorption and activation of carbon dioxide (CO₂) on low-lying compact (TiO₂)_n clusters are systematically investigated by using electronic structure calculations based on density-functional theory (DFT). Our calculated results show that CO₂ is adsorbed preferably on the bridge O atom of the clusters, forming a "chemisorption" carbonate complex, while the CO is adsorbed preferably to the Ti atom of terminal Ti-O. The computed carbonate vibrational frequency values are in good agreement with the results obtained experimentally, which suggests that CO₂ in the complex is distorted slightly from its undeviating linear configuration. In addition, the analyses of electronic parameters, electronic density, ionization potential, HOMO-LUMO gap, and density of states (DOS) confirm the charge transfer and interaction between CO₂ and the cluster. From the predicted energy profiles, CO₂ can be easily adsorbed and activated, while the activation of CO₂ on (TiO₂)_n clusters are structure-dependent and energetically more favorable than that on the bulk TiO₂. Overall, this study critically highlights how the small (TiO₂)_n clusters can influence the CO₂ adsorption and activation which are the critical steps for CO₂ reduction the surface of a catalyst and subsequent conversion into industrially relevant chemicals and fuels.     

Experimental and computational modeling of the biological activity of benzaldehyde sulphur trioxide as a potential drug for the treatment of Alzheimer disease

Alzheimer's disease is a major public brain infection that has resulted in many deaths as revealed by the world health organization (WHO). Conventional Alzheimer treatments such as chemotherapy, surgery, and radiotherapy are not very effective and are usually associated with several adverse effects. Therefore, it is necessary to find new therapeutic approach that completely treat Alzheimer disease without much side effects. In this research work, we report the experimental and in silico molecular modeling of the biological activity of a novel azo-based compound as potential candidate for Alzheimer's disease. The synthesized compound was obtained by coupling reactions with 4-amino-3-nitrobenzaldehyde. Suitable purification and characterization techniques were employed and density functional theory (DFT) computational approach as well as in-silico molecular modeling has been employed to assess the electronic properties and anti-Alzheimer's potency. Suitable protein targets often regarded as target sites for most therapeutic vaccines for the said disease (4EY7, 1QTN, 4EY7, and 6EUE) have been selected for molecular docking investigation. For proper valuation of the drug candidacy, molecular docking studies were compared with conventional Alzheimer drug (donepezil). Also, the spectroscopic properties of the studied compound were investigated and compared with experimental data. Our findings show that the studied structure is relatively stable and expresses greater binding affinities of ?6.10, ?9.01, ?5.90, and ?11.20 kcal/mol than donepezil which had binding affinities of: 5.30, ?6.30, 5.90, and ?10.70 kcal/mol for each protein target. Thus, demonstrating the efficacy of the studied compound as potential candidate for Alzheimer's disease.     

Vibrational Characterization and Molecular Electronic Investigations of 2-acetyl-5-methylfuran using FT-IR,FT-Raman,UV–VIS,NMR, and DFT Methods

Spectroscopic (FT-IR, FT-Raman, UV–vis, and NMR) techniques have been extensively used for structural elucidation of compounds along with the study of geometrical and vibrational properties. Herein, 2-acetyl-5-methylfuran, a derivative of furan, was experimentally characterized and analyzed in details using FT-IR, FT-Raman, UV–vis, and ¹H NMR spectroscopic techniques conducted in different solvents. The experimentally analyzed spectral results were carefully compared with theoretical values obtained using density functional theory (DFT) calculations at the B3LYP/6–311?+?+?G (d, p) method to support, validate, and provide more insights on the structural characterizations of the titled compound. The correlated experimental and theoretical structural vibrational assignments along with their potential energy distributions (PEDs) and all the spectroscopic spectral investigations of the titled structure were observed to be in good agreements with calculated results.

     

Ti3C2Tx-Modified PEDOT:PSS Hole-Transport Layer for Inverted Perovskite Solar Cells

PEDOT:PSS is a commonly used hole-transport layer (HTL) in inverted perovskite solar cells (PSCs) due to its compatibility with low-temperature solution processing. However, it possesses lower conductivity than other conductive polymers and metal oxides, along with surface defects, limiting its photovoltaic performance. In this study, we introduced two-dimensional Ti₃C₂T_x (MXene) as an additive in the PEDOT:PSS HTL with varying doping concentrations (i.e., 0, 0.03, 0.05, and 0.1 wt.%) to tune the electrical conductivity of PEDOT:PSS and to modify the properties of the perovskite film atop it. We noted that the grain size of the CH₃NH₃PbI₃ (MAPI₃) perovskite layer grown over an optimal concentration of MXene (0.03 wt.%)-doped PEDOT:PSS increased from 250 nm to 400 nm, reducing charge recombination due to fewer grain boundaries. Ultraviolet photoelectron spectroscopy (UPS) revealed increased work function (WF) from 4.43 eV to 4.99 eV with 0.03 wt.% MXene doping, making the extraction of holes easier due to a more favorable energy level alignment with the perovskite. Quantum chemical investigations based on density functional theory (DFT) were conducted at the ωB97XD/6-311++G(d,p) level of theory to provide more insight into the stability, bonding nature, and optoelectronic properties of the PEDOT:PSS–MXene system. The theoretical investigations revealed that the doping of PEDOT:PSS with Ti₃C₂T_x could cause a significant effect on the electronic properties of the HTL, as experimentally demonstrated by an increase in the electrical conductivity. Finally, the inverted PSCs employing 0.03 wt.% MXene-doped PEDOT:PSS showed an average power conversion efficiency (PCE) of 15.1%, up from 12.5% for a reference PSC employing a pristine PEDOT:PSS HTL. The champion device with a 0.03 wt.% MXene–PEDOT:PSS HTL achieved 15.5% PCE.     

Enhanced adsorption performance of a novel Fe‐Mn‐Zr metal oxide nanocomposite adsorbent for anionic dyes from binary dye mix: Response surface optimization and neural network modeling

A novel adsorbent, Fe‐Mn‐Zr metal oxide nanocomposite was synthesized and investigated for removal of methyl orange (MO) and eosin yellow (EY) dyes from binary dye solution. The magnetic nanocomposite has shown surface area of 143.01 m²/g and saturation magnetization of 15.29 emu/g. Optimization was carried out via response surface methodology (RSM) for optimizing process variables, and optimum dye removal of 99.26% and 99.55% were obtained for MO and EY dye, respectively with contact time 62 min, adsorbent dose 0.45 g/l, initial MO concentration 11.0 mg/l, and initial EY concentration 25.0 mg/l. A feed forward back propagation neural network model has shown better prediction ability than RSM model for predicting MO and EY dye removal (%). Adsorption process strictly follows Langmuir isotherm model, and enhanced adsorption capacities of 196.07 and 175.43 mg/g were observed for MO and EY dye, respectively due to synergistic effects of physicochemical properties of trimetal oxides. Surface adsorption and pore diffusions are the mechanisms involved in the adsorption as revealed from kinetic studies.     

特定位点上CO2与(TiO2)n团簇相互作用的第一性原理研究

本文基于密度泛函理论系统地研究了(TiO₂)_n团簇上二氧化碳(CO₂)的吸附和活化性质. 计算结果表明,CO₂更倾向于吸附在(TiO₂)_n团簇的桥氧原子上,形成“化学吸附”碳酸盐络合物. 而CO更倾向于吸附到末端Ti-O的Ti原子上. 发现计算得到的碳酸盐振动频率值与实验获得的结果非常吻合,这表明配合物中CO₂的几何构型与其线性型相比,有微小的弯转. 通过对电子结构、电荷密度、电离势、HOMO-LUMO以及态密度的分析,证实了CO₂与团簇之间的电荷转移以及相互作用. 从预测的能量分布图来看,(TiO₂)_n团簇上的CO₂活化与结构密切有关,相比于块体的TiO₂,CO₂在团簇结构上更易于吸附和活化.     

Modeling of Al12N12, Mg12O12, Ca12O12, and C23N nanostructured as potential anode materials for sodium-ion battery

Journal of Solid State Electrochemistry - The rising costs of lithium and other versatile metals which are of electrochemical importance have sprouted concerns in the electrochemical world. Sodium...