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In this work, surfactant-assisted hydrodistillation using the nonionic surfactant Triton X-100 is reported for the first time as an extraction strategy for essential oils (EOs) from the brown alga Dictyopteris membranacea, a species well known for its rich content of bioactive metabolites, including C11 hydrocarbons (sexual pheromones), sulfur-containing compounds, and terpenoids. A range of Triton X-100 concentrations was evaluated to optimize the extraction process, and the results were compared to conventional hydrodistillation, which yielded 0.12%. The extraction process exhibited three distinct phases: an initial increase in yield with rising surfactant concentration; a peak yield of 0.22% (w/w) observed at a Triton X-100 concentration of 8%–12% (v/v); and a subsequent decline at higher concentrations. EOs obtained under varying surfactant conditions were analyzed by GC-MS and GC-FID to assess the influence of Triton X-100 on their chemical profile. The results have extracting demonstrated a significant impact of surfactant concentration on the relative abundance of major compound classes, notably C11 hydrocarbons, terpenes, and sulfur-containing compounds.

The present research investigates the microwave-assisted synthesis of copper and iron nanoparticles which offers emerging strategies for development of eco-friendly and sustainable approaches leading to the environmentally responsible biomedical applications. This green chemistry approach was meant for the comparative study of the synthesized Copper and Iron nanoparticles from Embelia ribes and Peltophorum pterocarpum extracts. UV-visible spectroscopy, FT-IR, TEM, XRD and Zeta potential were used to characterize the synthesized Cu and FeNPs. The synthesized nanoparticles exhibited UV-Visible spectrum between 200-400 nm and FT-IR was done for the determination of functional groups. By utilizing TEM particle size were observed ranging from 10 to 50 nm. The XRD data depicted sharp and crystalline peaks and the stability studies showed zeta potential values at −12.43 and −11.93 mV. The comparative study of the synthesized nanoparticles showed that the CuNPs mediated by E. ribes exhibited significant zone of inhibition against bacterial pathogens for antibacterial and antifungal activity. The DPPH radical scavenging assay showed higher antioxidant capacity in FeNPs derived from P. Pterocarpum than CuNPs mediated by E. ribes, emphasizing the environmentally responsible, economical and sustainable ways to create Cu and Fe nanoparticles for use in medical applications.

We report the first successful synthesis and comprehensive optical characterization of Ce³⁺-doped RbCaMgF₃ nanophosphors, highlighting their potential for next-generation white LED applications. Structural analysis confirms the incorporation of Ce³⁺ ions into the cubic perovskite lattice without phase segregation, maintaining lattice integrity across all doping levels. FTIR spectra validate the stability of Mg–F and Ca–F bonding networks, while FE-SEM and EDAX reveal uniform nanocrystals with homogeneous elemental distribution. UV–vis diffuse reflectance spectroscopy shows a redshift in the absorption edge and a bandgap narrowing from 3.00 to 2.72 eV with increasing Ce³⁺ content, enabling efficient UV-to-visible energy conversion. The incorporation of Ce³⁺ ions into the host lattice modified the optical band gap, resulting in a significant enhancement of the emission intensity. Enhanced emission intensity is observed due to bandgap modulation, with a broad blue-green emission centered at 441.5 nm under 401 nm excitation, attributed to the 5d→4f transition of Ce³⁺ in a symmetric crystal field. The chromaticity coordinates (x = 0.33, y = 0.27) and correlated color temperature (5300 K) place the emission in the cool-white region of the CIE 1931 diagram.

Polyvinylidene chloride (PVDC) was one of the essential sealed packaging materials. The desirable production process of vinylidene chloride (VDC), as the polymer monomer of PVDC, urgently needs to be explored because of the shortcomings of the present process. The present investigation was focused on the dehydrochlorination of 1,1,2-trichloroethane (1,1,2-TCE, called as TCE here) to VDC over CsCl/Al₂O₃. The dehydrochlorination reaction of TCE was carried out in the continuous flow fixed reactor. The effects of content CsCl over CsCl/Al₂O₃ on the activity of TCE dehydrochlorination were investigated in detail. In addition, the stability and deactivation of 0.6CsCl/Al₂O₃ in TCE dehydrochlorination were also discussed. The prepared CsCl/Al₂O₃ catalysts were characterized by XRD, NH₃-TPD, CO₂-TPD, and N₂ adsorption-desorption. The results showed that the conversion of TCE dehydrochlorination was improved up to a maximum with the increment of CsCl loading over CsCl/Al₂O₃ to 1.0% and then appreciably decreased with further increase of CsCl loading. VDC selectivity was also enhanced with the increase of CsCl loading to 0.6%, and then it was almost leveled off at higher loading. The CsCl loading on Al₂O₃ greatly reduced the acid sites and produced new base sites. Therefore, it could be considered that the new base sites over CsCl/Al₂O₃ should be responsible for the improvement of TCE dehydrochlorination activity, although the catalyst activity could not be well correlated with the number of base sites on CsCl/Al₂O₃. The deactivation of 0.6CsCl/Al₂O₃ at the initial reaction stage should be attributed to the coverage of base sites by the polymerization macromolecules.

Strontium hydroxyapatite (SrHA) and its halogen-substituted derivatives, strontium fluorapatite (SrFA) and strontium chlorapatite (SrClA), were synthesized using a chemical precipitation method and characterized using XRD, FT-IR, and FE-SEM. The incorporation of fluorine and chlorine into the SrHA lattice affected the crystal structure and morphology of the material. Electrochemical investigations revealed that SrClA exhibited the largest electrochemical surface area among the synthesized materials, which directly correlated with its enhanced acetaminophen (AC) sensing capability. The key parameters, including pH, accumulation time, and scan rate, were optimized to maximize the sensor response. Under optimized conditions, the SrClA-modified carbon paste electrode achieved a low limit of detection of 79 nM for AC, with a wide linear concentration range (5–200 µM). Density Functional Theory (DFT) studies provided insights into the sensing mechanism, revealing the strongest interaction between AC and SrClA, corroborating the electrochemical findings. The hydroxyl and carbonyl oxygens of AC showed favorable adsorption, with binding energies indicating the order of interaction strength as SrClA > SrHA > SrFA. These results highlight the potential of SrClA as a sensitive and effective electrochemical sensor for AC detection, offering a promising approach for rapid and accurate analysis.

In quinone diazides, the ortho or para diazo carbons are rendered electrophilic and therefore susceptible to reaction with simple nucleophiles such as halides in an umpolung of phenol reactivity. The reaction of a range of ortho- and para-quinone diazides, readily prepared by diazotization of amino-phenols or -naphthols, with halide anions (chloride, bromide, iodide) gives ortho- or para-halogenated phenols in moderate to excellent yield. The effect of solvent, catalyst, nucleophile, and diazo substrate on the reaction was investigated, although attempts to extend the process to the nucleophilic addition of fluoride resulted in only trace quantities of fluorophenol being formed.

Neurotherapeutics that target kinases are necessary because Alzheimer's disease (AD) is characterized by a persistent decrease in cognitive function that is linked to amyloid-β accumulation and tau hyperphosphorylation. This research highlights the dietary flavonoid morin as a potential therapeutic agent through a comprehensive integrated approach that incorporates network pharmacology, molecular docking, long-timescale molecular dynamics (MD), density-functional theory (DFT), and in silico ADMET profiling. With a focus on the significance of GSK-3β in AD, network pharmacology successfully connected Morin's predicted targets with genes relevant to AD by highlighting important kinase hubs using the STRING/Cytoscape and DAVID/ShinyGO tools. Within the ATP site of GSK-3β (PDB: 8FF8), Morin showed a competitive binding score of around −8.8 kcal/mol in docking tests. Along with contact with Gly185, Asp200, Lys85, and Phe67, it formed crucial connections with residues like Val135 and Asp133. The stability of the docking posture was validated by molecular dynamics simulations conducted over 1000 ns. The ligand RMSD averaged 3.58 ± 0.92 Å, whereas the protein Cα RMSD stabilized at 2.34 ± 0.31 Å, indicating a stable kinase conformation and a consistent contact network. The DFT study provides electronic descriptors that show how well Morin works in π-stacking and hydrogen-bonding interactions, which are crucial for its role in kinase pockets. Morin has problems with blood–brain barrier (BBB) permeability. However, ADMET profiling indicates that it is feasible for oral administration with minimal Geno and cardiotoxic hazards. Therefore, the need for CNS-targeted delivery methods, including lipid carriers, prodrugs, or intranasal routes, is highlighted. The combination of network pharmacology, docking fidelity, MD stability, good electrical properties, and a respectable ADMET profile makes Morin a viable option for GSK-3β inhibition in AD. Research is underway to support its therapeutic potential via experimental validation using CNS-targeted formulation studies, neuroprotective assessments, and enzyme inhibition experiments.

The rapid rise of antimicrobial resistance necessitates the development of new chemotypes with improved efficacy and drug-like properties. In this study, 10 previously unexplored azetidine–pyridazine scaffolds were synthesized under mild, metal-free conditions, and evaluated for their dual antibacterial and antifungal potential. Several derivatives displayed strong in vitro activity against Staphylococcus aureus, with five compounds outperforming chloramphenicol. Two compounds also exhibited twofold higher antifungal potency than griseofulvin against Candida albicans. All molecules demonstrated favourable ADMET characteristics, including high predicted gastrointestinal absorption, no violations of drug-likeness rules, and non-substrate behaviour toward P-glycoprotein. DFT-based electronic analysis and molecular docking against DNA gyrase (5MMN) and CYP51 (3JUV) provided molecular-level justification for the observed SAR and antimicrobial effects. Overall, the combination of green synthesis, potent bioactivity, desirable pharmacokinetics, and strong target interactions highlights azetidine–pyridazine scaffolds as promising leads for future antimicrobial drug development.

Mesoporous MCM-41 serves as an ideal support due to its large surface area, ordered pore structure, and thermal resilience. Nickel (II) stands out among transition metals for its abundance, low cost, and adaptable coordination chemistry, making it suitable for immobilization via Schiff base ligands to drive various organic transformations. Motivated by these factors, we prepared a novel MCM-41-supported Ni (II) Schiff base catalyst, designated as M41@CP@AnL@Ni (1). The catalyst 1 was characterized by various techniques and tested for the formation of tetrahydropyrazolopyridines. The synthesis of tetrahydropyrazolopyridines was carried out in a single vessel by combining ethyl acetoacetate, hydrazine hydrate, an aromatic aldehyde, and ammonium acetate under mild conditions. The catalyst 1 demonstrated good catalytic performance and selectivity, afforded product yields of up to 97%, especially with electron-deficient aryl aldehydes under mild thermal conditions (80 °C). The insignificant metal leaching and the absence of any measurable decline in the activity underscore its operational robustness and superior applicability relative to conventional catalytic systems. A feasible reaction mechanism has been proposed. These findings, in conjunction with the catalyst's observed efficiency, provide strong experimental support for the proposed pathway and highlight the critical involvement of the Ni (II) active site throughout the catalytic cycle.

3-(2-formylcycloalkenyl)-acrylic ester (FCAE) acts as an important building block in synthetic organic chemistry. Co-existence of α, β-unsaturated ester and α, β-unsaturated aldehyde makes it a useful scaffold for the synthesis of diverse carbocyclic and heterocyclic compounds through Michael addition, condensation reaction, coupling reaction, multicomponent reaction, cascade cyclization, functional group conversion, and asymmetric synthesis. The literature covers the area since last couple of decades. In this review, we outline the various pathways for bicyclic, tricyclic, tetracyclic, pentacyclic, and polycyclic heterocyclic scaffolds with their mechanistic details.