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Zinc oxide nanoparticles (ZnO NPs) have drawn some attention due to its antimicrobial properties and potential for their usage in biomedicine. ZnO NPs were synthesized using algal biomass filtrate, characterized subsequently, and the antimicrobial, antibiofilm, and cytotoxic activities of the ZnO NPs were evaluated. The synthesized ZnO NPs were characterized with fourier transform infrared, X-ray Diffraction, scanning electron microscopic, and transmission electron microscopy to analyze their morphological and compositional properties. Agar well diffusion, time-kill assays and antibiofilm experiments were conducted to assess antibacterial efficacy, while Artemia salina nauplii were used to evaluate cytotoxicity. It was found that ZnO NPs had hexagonal wurtzite crystal structure, uniform nanoscale morphology ranging 20-90 nm, and high phase purity. ZnO NPs exhibited potent antibacterial activity, further confirmed by molecular docking analysis. Strong antibiofilm efficacy, reducing biofilm biomass by up to 95%. Exceptional results were shown by wet lab and docking validation. The PBP2a protein of S. aureus showed a binding score of -7.7, indicating strong inhibition by the ZnO NPs. These nanoparticles exhibit a dose-dependent response, where minimal toxicity was observed at lower concentrations. This study highlights the potential of algae-mediated ZnO NPs as a green, sustainable antimicrobial platform that may mitigate the microbial resistance problem.

In this study, the condensation reaction between vinamidinium salts and Z-2-hydrazineylidene-3-methyl-2,3-dihydrobenzo[d]thiazole is described for the synthesis of 1,3-bis((3-methylbenzo[d]thiazol-2(3H)-ylidene)hydrazineylidene)propan-2-ol (BBTA) or 1-((1Z,3E)-1-(dimethylamino)-3-(((Z)-3-methylbenzo[d]thiazol-2(3H)-ylidene)hydrazineylidene)prop-1-en-2-yl)pyridin-1-ium (DMBT). A noteworthy aspect of the synthesis of these derivatives is that the structure of the vinamidinium salt acts as the determining factor for the type of product formed. Specifically, phenyl-substituted vinamidinium salts predominantly lead to the formation of symmetric BBTA derivatives, whereas pyridinium-based vinamidinium salts favor the production of asymmetric DMBT compounds. The reaction was carried out in the presence of triethylamine as the base and acetonitrile as the solvent under catalyst-free conditions. The structure of the new products was confirmed based on their spectral data, including ¹H NMR, ¹³C NMR, IR, mass spectrometry, high-resolution mass spectrometry and X-ray analysis.

Particle size is crucial for sedimentation processes. However, there is limited research on how varying particle sizes influence the sedimentation of fine-grained particles. This study examined the aggregation behavior of two types of montmorillonite particles with different sizes under different concentrations of Al³⁺. The findings indicated that the sample of fine particles exhibited a more rapid reduction in turbidity and a greater increase in the absolute value of surface potential across various Al³⁺ concentrations. Despite this, both samples achieved comparable final supernatant turbidity, sediment layer height, and residual particle size, suggesting that the enhancing effect of Al³⁺ on the sedimentation of fine-grained montmorillonite is limited by particle size. Different concentrations of Al³⁺ result in the formation of hydroxyl compounds and hydroxides that adsorb onto mineral surfaces, promoting the sedimentation of finer-grained montmorillonite in the sample of fine particles. DLVO theory confirmed that the electrical double layers of the samples of coarse and fine particles gradually diminished under the influence of Al³⁺, effectively enhancing the aggregation of montmorillonite. Furthermore, thermodynamic analysis suggested that particles smaller than 500 nm do not settle further, even with the addition of aluminum ions.

Small-molecule amines, typically studied in their more stable and water-soluble protonated forms, are of central importance in drug discovery. Their structural diversification often relies on N-alkylation, yielding mixtures of analogs with varying degrees of substitution-posing a key challenge for purification. While advanced chromatographic techniques exist, no high-throughput, broadly applicable alternative has emerged that aligns with the capabilities of automated synthesis. Here, a reusable microplate-based assay enabling ultra-high-throughput, parallel separation of protonated amines-including alkyl-, aryl-, and aralkylamines-at submicromolar levels is reported. The method exploits a covalently immobilized tris(pyridino)-crown ether selector, which forms reversible host-guest complexes by H-bonds, which differ with the degree of N-substitution. This supramolecular recognition strategy eliminates the need for compound-specific method development, derivatization, or preparative-scale quantities. In addition, the present article introduces a generally applicable surface-functionalization protocol for customizing standard commercial microplates into molecular recognition platforms. The present approach resolves key limitations of current separation technologies-such as high energy use, low integration with liquid-handling systems, inevitable sample dilution, and time-intensive workflows-offering a transformative tool for rapid and efficient purification directly compatible with modern synthesis pipelines.

The density functional theory (DFT) method ωB97XD/6-311+G(2d, p) was employed to perform systematic theoretical calculations and comparative analyses on the geometric structures, spectroscopic properties, frontier molecular orbitals, and molecular electrostatic potentials of potential antibacterial compounds derived from 16-membered lactone ring-containing secondary metabolites of extremophiles, as well as midecamycin. The reactivity indices of these compounds were further investigated within the framework of conceptual DFT. Additionally, drug-likeness was evaluated using two independent pharmacokinetic prediction platforms, and molecular docking simulations were conducted to assess their binding affinities. The results indicate that the carboxyl hydrogen, hydroxyl hydrogen, and carbonyl oxygen atoms in these molecules exhibit relatively high reactivity. Compound 3 displays relatively high chemical reactivity, whereas compounds 6 and 9 demonstrate superior chemical stability combined with significant reactivity. Pharmacokinetic predictions reveal poor Caco-2 permeability for compounds 8 and 9, low therapeutic indices for compounds 2 and 3, and the highest metabolic stability in human liver microsomes for compound 7. Overall, compound 1 exhibits the highest structural and physicochemical similarity to midecamycin. Compound 1 was evaluated for molecular docking with the 50S ribosomal subunit from Streptomyces bacteria; the molecular docking results confirm its distinct binding affinity, despite a slightly higher binding energy. The molecular dynamics simulation results indicate that complex 1 exhibits a Gibbs free energy of -30.76 kJ/mol, further supporting its structural stability.

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) has long been recognized as a versatile organic oxidant that mediates diverse transformations through single-electron transfer, hydride abstraction, and redox cycling. Beyond its classical stoichiometric role in oxidation and dehydrogenation, DDQ now serves as an efficient catalyst for carbon-carbon bond formation across thermal, photochemical, and electrochemical domains. In stoichiometric reactions, DDQ enables benzylic and allylic CH activation to generate oxocarbenium or iminium intermediates that couple with a broad range of nucleophiles, facilitating alkylation, arylation, cyanation, and annulation processes. In catalytic systems, DDQ participates in redox cycles where the DDQ/DDQH₂ couple is regenerated by oxidants such as O₂, nitrites, or MnO₂, offering mild and simple access to complex carbon frameworks. The scope further extends to asymmetric catalysis and radical-mediated cross-dehydrogenative coupling, providing sustainable routes to natural product-like scaffolds and biologically active molecules. This review highlights the progression of DDQ from a stoichiometric oxidant to a redox-active catalyst, emphasizing its growing utility in controlled, metal-free oxidative CC bond formation and its promise for next-generation sustainable synthesis.

The influence of pre-adsorbed water (D₂O) on the growth, adsorption, orientation, and thermal behavior of two ionic liquids (ILs) on Pt(111) was studied within the SCILL (solid catalyst with ionic liquid layer) concept. Nonfunctionalized [C₁C₁Im][Tf₂N] and nitrile-functionalized [C₃CNC₁Im][Tf₂N] were deposited at ∼100 K onto clean Pt(111) or onto single-layer and multilayer crystalline (CI) or amorphous (ASW) D₂O films and analyzed at various temperatures by angle-resolved X-ray photoelectron spectroscopy (ARXPS). On both clean and D₂O-covered Pt(111), the ILs initially grow in a 2D layer-by-layer mode, forming a closed wetting layer at ≈ 0.5 ML IL coverage, followed by moderate 3D growth above 0.8-1.0 ML. At 100 K, the ILs partially displace D₂O from the Pt surface, yielding co-adsorption structures where IL contacts Pt(111) directly and is also located in a second layer. [Tf₂N]^- anions adsorb in cis-configuration with oxygen atoms toward the surface, while the cations adopt mixed parallel and tilted orientations. Heating to 130 K induces rearrangement, increasing direct IL-Pt(111) contact by favoring parallel cation alignment. Co-adsorbed D₂O remains but desorbs at ≈10 K lower temperature, indicating weaker binding to Pt. The similar interfacial behavior of both ILs shows that the nitrile group does not significantly influence adsorption geometry or thermal stability.

A new class of pyrido[2,3-d][1,2,4]triazolo[4,3-a]pyrimidinones and pyrido[2,3-d]thiazolo[3,2-a]pyrimidinones was synthesized by reacting 5-phenyl-2-thioxo-2,3-dihydropyrido[2,3-d]pyrimidin-4(1H)-one with hydrazonoyl halides and α-bromoketones via a Knoevenagel-cyclocondensation followed by heteroannulation. Structures were confirmed by elemental analysis and IR, ¹H NMR, and MS spectroscopy. Cytotoxicity against HepG2 cells (MTT assay) revealed submicromolar activity for the most active analogs (IC₅₀ 0.72-0.95 µM), comparable to doxorubicin (0.65 µM). Structure-activity trends indicate that ester functionalities, coumarin incorporation, and electron-donating aryl substituents enhance potency. Molecular docking to the EGFR kinase domain showed strong predicted binding for the top analogs (scores -9.6 to -10.2 kcal mol^-1 vs -8.7 kcal mol^-1 for doxorubicin), highlighting key hydrogen-bond and hydrophobic contacts with Lys745, Asp837, Arg841, and Asp855. Docking results align with the in vitro data. In silico ADMET predictions suggest favorable drug-likeness, oral absorption, and non-mutagenic character. These findings position the reported pyridopyrimidine scaffolds as promising EGFR-targeted anticancer leads.

This study evaluated the sedative activity of abietic acid (AA) through a thiopental sodium (TS)-induced sleep model in mice. AA (5, 10, and 20 mg/kg) and diazepam (DZP) (2 mg/kg) were provided, followed by TS (20 mg/kg) after 30 min to induce sleep. Sleep latency and total sleeping time were documented over a 4 h period. Additionally, molecular docking studies were conducted to examine the interactions of AA with GABA_A (Protein Data Bank: 6X3X) receptors, which hold two subunits of α1 and β2, alongside pharmacokinetic and toxicity assessments. The results indicated that AA significantly (p < 0.05) provided the fast onset of sleeping and extended sleeping time in a dose-dependent manner. The combination of AA (20 mg/kg) with DZP further enhanced sedation, yielding a prolonged sleep duration and a reduced sleep latency, indicating a synergistic effect. In addition, in silico analysis expressed that AA exhibited a strong binding affinity for GABA_A receptors (-7.9 kcal/mol), comparable to DZP (-8.4 kcal/mol). Furthermore, AA demonstrated favorable pharmacokinetic properties and drug-likeness. Overall, these findings suggest that AA possesses potent sedative effects, likely mediated through interactions with the GABAergic system, warranting further investigation for its therapeutic potential in sleep disorders.

Azobenzene derivatives, which show light-induced reversible trans↔cis isomerization, have gained increasing attention in the area of protein science. p-(Phenylazo)-L-phenylalanine (Pap) was recently employed to enable the light-controlled affinity purification of biosynthetic proteins as part of the Azo-tag. Specific supramolecular complex formation with immobilized α-cyclodextrin (α-CD) groups is mediated by the Pap side chain in its low-energy trans-configuration, whereas photoisomerization to the cis-state leads to immediate dissociation. Here, we describe the X-ray crystallographic analysis of super-folder green fluorescent protein (sfGFP) displaying Pap at amino acid position 39 on its surface in complex with α-CD. While this experimental structure generally confirms the mode of host-guest interaction predicted by molecular modeling, there are two unexpected observations: (i) the conically shaped α-CD binds with its narrow end toward the aminoacyl moiety of Pap, despite appearing sterically more demanding, and (ii) the azobenzene side chain shows a considerably twisted conformation of its two phenyl rings, which contrasts with the fully coplanar arrangement usually anticipated for unmodified azobenzene and its chemical derivatives. Thus, this crystal structure of the photoswitchable noncanonical amino acid Pap (also known as AzoF or AzoPhe) provides valuable insight for future molecular engineering endeavors to endow proteins with light-controllable functions.