Abstract: This study examines the reactivity of an intramolecular cyclization process involving benzastatin, a molecule derived from Streptomyces nitrosporeus, using density functional theory (DFT) with the B3LYP functional and the 6-311G(d,p) basis set. Parr indices, calculated by natural bond orbital (NBO) analysis, provide insight into the reactivity and chemical behavior of the system. In addition, the electron localization function (ELF) is used to analyze bond formation during the process. A molecular docking study highlights the pharmacological potential of benzastatin-derived alkaloids against Plasmodium falciparum, the malaria parasite, by targeting the key enzymes falcipain-2 and falcipain-3. The study elucidates the key interactions and binding affinities between the reaction products involved and these enzymes, supported by molecular dynamics simulations to study the stability of the ligand-protein complex over 50 ns. ADMET predictions suggest favorable pharmacokinetic profiles and low toxicity for the compounds, underlining their potential as antimalarial drug candidates.

Abstract: Angular pyrrolo(pyrido)[1,2-a]quinazolinones, being structurally isomeric to linear pyrrolo(pyrido)[2,1-b]quinazolinone alkaloids, are attractive molecular systems for both synthetic transformations and targeted biomedical research. The pyrrolo(pyrido)[1,2-a]quinazolinone scaffold has proven to be quite effective in the search for compounds with a wide range of pharmacological activities, e.g. anti-inflammatory, antioxidant, antibacterial, antiarrhythmic, and inhibitors of important biotargets. The present review summarises the methods for the synthesis of pyrrolo(pyrido)[1,2-a]quinazolinones as a comprehensive research object, especially in the past decade. They are systematised according to the type of heteroannulation and include the processes of cascade annulation of the pyrimidine and pyrrole (pyridine) cycles to anthranilamides (hydrazides); formation of a pyrimidine nucleus based on ortho-pyrrolyl(pyridinyl) substituted aromatic compounds; annulation of the pyrrole (pyridine) nucleus to a quinazolinone scaffold. It is expected that the generalised material presented will serve as a reliable guide for the rational design of new pharmacologically oriented compounds

Abstract: Population growth and economic development have led to an increase in global energy consumption. Solar energy, a major renewable source, is essential to meeting human energy needs. This study, four new organic dyes (A1–A4) with a D–π–D–A structure using DFT and TD-DFT techniques for their potential application in dye-sensitized solar cells (DSSCs). The impact of π-bridge modifications of the A0 (reference molecule) on the structural, photovoltaic, optical and electronic properties was analyzed. The dyes showed band gaps (Egap) ranging from 2.4 to 3.5eV and absorption wavelengths (λ) from 420.16 to 627.4nm. Results suggest that the modification of the π-bridge of dye A0 enhanced intramolecular charge transfer (ICT). and improved hole injection. Theoretical open-circuit voltages (Voc) varied between 1.15 and 2.36 eV, while light harvesting efficiency (LHE) values ranged from 0.80 to 0.93. This study could effectively assist chemists in the synthesis of efficient dyes for DSSCs.

Abstract: The (3+2) cycloaddition reactions of 2-diazopropane with derivatives of 5-hydroxy-3-methyl-1,5-dihydropyrrol-2-one were investigated using Molecular Electron Density Theory. Calculations were performed at the wB97XD/6-311++G(d,p) level of theory. Conceptual Density Functional Theory indices revealed a low polar character for these reactions, supported by a minimal global electron density transfer at the transition structures, which were classified as forward electron density flux processes. The Electron Localization Function analysis identified 2-diazopropane as a pseudo(mono)radical three-atom component. It further indicated that bond formation does not start at the transition structures. Mechanistically, these reactions proceed via an asynchronous one-step mechanism, ultimately leading to products that are kinetically favored. Furthermore, molecular docking studies were conducted to evaluate the antifungal potential of the reaction products against pathogenic fungal strains, Candida albicans and Aspergillus fumigatus. The docking analysis assessed binding affinities and characterized molecular interactions between the proposed compounds and critical fungal proteins, highlighting their potential as antifungal agents.

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Abstract: A combined experimental and theoretical study of the fundamental thermodynamic parameters of 3-(5-phenyl-1-(pyridin-3-yl)-1H-pyrrol-2-yl)propanoic acid was carried out for the first time. The enthalpies of combustion, formation in the condensed state, fusion, and vaporization were determined using high-precision equipment. Based on the experimentally obtained results, the enthalpies of sublimation and formation in the gaseous state at 298.15 K were calculated using two methods. The possibility of applying analytical methods of Domalski, Joback and quantum chemical calculations to determine the enthalpy of formation in the gas phase is analysed.

Abstract: Triazolo[3,4-b][1,3,4]thiadiazole molecules are found to be important tools in modern bioorganic and medicinal chemistry. This condensed system successfully combines two pharmacologically significant five-membered heterocycles – 1,2,4-triazole and 1,3,4-thiadiazole, which causes much more interest in the enhanced activity profile of its analogs than their parent separate constituents. It’s considered that the triazoles fused to thiadiazoles exhibit various therapeutically important properties, probably due to the existence of N-C-S fragments in their structures. In this review, we presented the summarized literature data about the diversity of pharmacological effects of [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole based compounds as promising objects for the rational design of drug-like molecules.

Abstract: The present paper elicits the studies on synthesis and potential pharmacological applications of pyrazolo-oxazole heterocyclic scaffolds. The synthesized compounds were characterized by different spectroanalytical tools including ¹H NMR, ¹³C NMR, and FTIR techniques, followed by molecular docking-based biological interaction studies. Synthesized pyrazolo-oxazoles (8a–f) were docked against the heme-binding protein of P. gingivalis, an oral pathogen, responsible for a number of diseases. Among the synthesized heterocycles, compounds 8e and 8f showed better docking scores compared to the marketed drugs and thus are of great interest as lead compounds in developing treatment profiling to combat P. gingivalis-borne diseases.

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Abstract: Dye-sensitized solar cells (DSSCs) offer several advantages over traditional silicon-based solar cells, such as lower cost, versatility, and transparency. Titanium dioxide (TiO2) is widely used as a photocatalyst in DSSCs due to its chemical stability, high photocatalytic activity, photostability, and non-toxicity. This study provides a computational analysis of the geometric, electronic, optical, and photovoltaic properties of ten novel dyes using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT). To our knowledge, these dyes have not been previously explored in the literature. Our findings indicate that structural modifications can significantly enhance the electronic, optical, and photovoltaic properties of these dyes. The B3LYP functional was identified as the most effective for predicting the geometric and electronic properties, while TD-DFT calculations with the CAM-B3LYP functional and the 6-31G(d,p) basis set accurately predicted the absorption properties. The absorption maxima of the dyes ranged from 427.82 nm to 755.93 nm, with strong UV-Vis absorption attributed to delocalized π-π* transitions. The calculated band gaps varied from 1.928 eV to 2.425 eV, showing that increased conjugation leads to reduced band gaps and improved dye performance. Open-circuit voltage (Voc) values for TiO₂ ranged from 0.893 eV to 1.38 eV, suggesting good potential for efficient electron injection into the TiO2 conduction band. In conclusion, the ten novel dyes studied exhibit significant potential for use in DSSCs, and the theoretical methods employed here offer a reliable framework for predicting the properties of other materials. This approach can guide the development of new materials designed to improve the performance of DSSCs.

Abstract: The present study analyzes the characterization of adhesion properties in intermediate layers of asphalt pavement, a critical factor influencing road durability and performance. The research is based on a systematic review of scientific literature, highlighting different methodologies for evaluating interlayer bonding, experimental tests, and international standards such as AASHTO, ASTM, and MTC regulations. A comparative analysis was conducted between samples obtained from the “Improvement of the Santa Maria - Santa Teresa - Hydroelectric Machu Picchu Bridge Road” project and laboratory simulations using the LOTTMAN test. The results demonstrate that the amount of tack coat significantly affects interlayer adhesion. Experimental tests confirmed that a tack coat application rate of 0.4 l/m² provides optimal indirect tensile strength (TSR) values, improving mechanical bonding between asphalt layers. Moreover, findings indicate discrepancies between laboratory simulations and real-world construction data, emphasizing the need for field verification to ensure adherence to project specifications. The study concludes that optimizing tack coat application techniques is crucial for enhancing pavement structural integrity. Future research should focus on refining non-destructive testing methods, such as the Falling Weight Deflectometer (FWD), to evaluate interlayer adhesion in situ. Establishing standardized adhesion evaluation protocols will contribute to more durable and cost-effective pavement infrastructure.

Abstract: In the present work, an enaminedione 2 was easily obtained in excellent yield (92 %) by the N-N exchange reaction of DAMFA (diethylaminomethylenehexafluoroacetylacetone) 1 with ethyl glycinate hydrochloride using the Michael 1,4-addition/elimination approach. The obtained compound 2 was used as a precursor in the development of a new synthesis of 3-trifluoromethyl pyrrole 3 and 4-trifluoromethyl-(1H)-2-pyridinone 4. A mechanism involving nucleophilic substitution and intramolecular cyclization is proposed. The obtained compounds were identified and confirmed by Fourier transform infrared spectroscopy, proton and carbon nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry. The results of the analyses are in good agreement with the proposed structures of the synthesized compounds.

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Abstract: In this study, the movement dynamic of fenitrothion (50% EC) and thiobencarb (50% EC) was investigated using the field lysimeter in the presence of rice plant at four different levels of soil depth. Iodide was used as an indicator of the mobility of these pesticides through the soil in the field lysimeter. Iodide was detected in the leachates collected at level 1 and 2 only, the concentration of iodide collected from level 2 was more than those collected from level 1. The highest breakthrough curve for fenitrothion or thiobencarb was produced from the level 4 (deep level) followed by level 3 while the breakthrough curve of level 1 was the lowest peak. Significant differences were observed among the cumulative amounts of fenitrothion or thiobencarb collected from different depth levels. The pesticide residues in the leachates increase with the depth of soil profile increase. The cumulative amounts of the two tested pesticides were compatible with the concentration of treatments, and were higher in high-treatment (50 μg/g soil) compared with that in low-treatment (25 μg/g soil). Our results obtained leaching of thiobencarb was slightly higher than the leaching of fenitrothion. These results are useful in understanding the movement of pesticides and agrochemicals in the agricultural environment.

Abstract: A series of new benzimidazole phosphonate derivatives was obtained via nucleophilic addition of triethyl phosphite to the imine of the imidazole subgroup under solvent-free conditions. Structures of the formed products were confirmed using spectroscopic data (ATR-FTIR, ¹H-NMR, ¹³C-NMR, and MS). The antimicrobial profiles of the synthesized compounds were examined, and promising activities against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were revealed, showing significant inhibition zone diameters ranging from 13 to 17 mm. Alongside these experimental findings, in silico investigations were conducted using ADMET characteristics, which showed a positive pharmacokinetic profile and provided valuable information on potential interactions with target molecules. Besides, docking studies against tested microorganisms revealed further insights on the compounds’ binding interactions with the active sites. Finally, DFT analysis was performed to shed light on the synthesis of novel molecules.

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Abstract: The C3 or O-alkylation of 4-hydroxycoumarin (formation of new C-C and C-O bond) is undoubtedly one of the most important and challenging reactions in synthetic chemistry due to its pharmaceutical utility. In this communication, we report sulfated tin oxide (STO)-catalyzed synthesis of arylated vinyl ethers in moderate to good isolated yields (68-93%) from the reaction of substituted phenyl acetylenes (terminal alkynes) with 4-hydroxy coumarin in polyethylene glycol (PEG 400) as solvent at 110 oC. The catalyst can be recycled up to 5 times without losing the significant yield.

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Abstract: This theoretical study investigates the adsorption of eco-friendly tannins on cellulose surfaces as a means to develop sustainable wood adhesives with reduced formaldehyde emissions. Conceptual density functional theory calculations reveal the global and local chemical reactivity parameters governing the interaction between tannins and wood substrates. Monte Carlo simulations explore the configuration space of substrate adsorbate, while molecular dynamics simulations elucidate the binding strength and stability of tannins. The results demonstrate that tannins adsorb parallel to the cellulose surface, driven by donor-acceptor interactions. The adsorption energy calculations reveal spontaneous adsorption, with prodelphinidin exhibiting the strongest adsorption energy. This research provides valuable insights into the adsorption behavior of tannins and contributes to the development of eco-friendly wood adhesives that mitigate formaldehyde emissions.

Abstract: In the present study, it was demonstrated that a new series of derivatives of 1,2-diphenyl-3H-spiro[benzo[d]pyrrolo[2,1-b]triazol-3,5′-pyrimidine (4) and 3,2′-indandione (6) were efficiently designed and synthesized via a novel, and less cumbersome one-pot methodology involving tri-component interactions among benzotriazole, 2-chloro-2-phenylacetophenone, and 1,3-dicarbonyl compounds in CH₂Cl₂ at room temperature 25°C for 3 hours without the use of a catalyst. The resulting compounds' structural configurations were verified with NMR, IR, EI-MS, and elemental analysis exhibiting good yield and high purity.

Abstract: A thorough analysis of developments in machine learning (ML) and deep learning (DL) technologies for skin cancer diagnosis is provided in this research. It investigates how ML and DL could improve the precision and effectiveness of melanoma, basal cell carcinoma, and squamous cell carcinoma detection. By looking at current studies, the study emphasizes the use of neural networks, convolutional neural networks (CNNs), support vector machines (SVM), random forests, and k-nearest neighbors (KNN) in the diagnosis of skin cancer. Key findings show that DL models, including VGG, ResNet, and Inception benefit from huge datasets and sophisticated data augmentation strategies to attain high accuracy, sensitivity, and specificity. The paper also discusses the challenges and limitations associated with these technologies, such as the requirement for extensive annotated datasets. The study concludes with a call for collaboration to overcome current challenges and enhance the practical application of ML and DL in skin cancer detection.

Abstract: In this report, a facile and efficient method for the synthesis of imidazopyrimidine and triazolopyrimidine derivatives using cadmium incorporated fluoroapatite encapsulated γ-Fe2O3 magnetic nanocatalyst is presented. To investigate the catalytic properties of γ-Fe2O3@FAp@Cd nanocatalyst, one-pot three-component reaction of malononitrile, aromatic aldehydes and 2-aminobenzimidazole or 3-amino-1,2,4-triazole was used. In this method imidazo[1,2-a]pyrimidine and 1,2,4-triazolopyrimidine derivatives were obtained in short reaction time (10-15 minutes) and excellent yield (85-95%). The catalyst was characterized by using analytical techniques such as FT-IR, XRD, SEM, EDX, VSM and used in five consecutive runs without notable decrease in its catalytic performance.

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