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Cyclin-dependent kinase 4 (CDK4) plays a pivotal role in cell cycle regulation and is a well-established target in cancer therapy. Triazolopyrimidines, as bioactive heterocyclic compounds, represent a promising scaffold for the development of novel anticancer agents. Herein, a new series of 1,5-dihydro-[1,2,4]triazolo[4,3-a]pyrimidine derivatives (5a-g) is synthesized via multistep reactions involving 6-methyl-4-phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl propionate and hydrazonoyl halides. Structural confirmation is achieved through infrared spectroscopy, ¹H nuclear magnetic resonance, mass spectrometry, and elemental analysis, and further supported by alternative synthetic approaches. Molecular docking studies targeting the CDK4/cyclin D1 complex (PDB ID: 2W9Z) reveal favorable binding interactions, particularly for compounds 5c and 5d, with binding energies of -7.34 and -7.25 kcal/mol, respectively. In vitro cytotoxicity assays against HepG2 liver cancer cells show that compounds 5c, 5d, and 5f exhibit potent activity, with IC₅₀ values of 4.38, 3.96, and 3.84 µM, respectively, comparable to doxorubicin (3.43 µM). A similar trend is observed in MCF-7 breast cancer cells, where 5c, 5d, and 5f again demonstrate strong antiproliferative effects with IC₅₀ values of 4.12, 3.87, and 3.95 µM, respectively, close to doxorubicin (3.25 µM). The absorption, distribution, metabolism, excretion, and toxicity profile indicates excellent absorption, moderate distribution, low toxicity, and favorable drug-likeness. These findings highlight the potential of the synthesized triazolopyrimidine derivatives as promising leads for CDK4-targeted anticancer drug development.

The reaction of silylated alkynes with acid chlorides in the presence of Lewis acids, first described by Birkhofer in 1963, has since emerged as a valuable method for the synthesis of alkynones. Despite its broad synthetic utility, the original protocol suffers from notable drawbacks, including the use of toxic solvents, stoichiometric Lewis acids, and corrosive acylating agents. In light of growing environmental concerns, a more sustainable alternative is developed. Herein, catalytic amounts of iron(III) chloride in combination with biodegradable acetic anhydride enable the efficient synthesis of alkynones under mild conditions.

The indiscriminate use of antibiotics has led to the selection of resistant bacterial strains, significantly reducing the effectiveness of conventional treatments. In this context, thiadiazines have emerged as promising agents due to their antioxidant and antibacterial properties. This article aims to evaluate the antibacterial potential of synthetic thiadiazine analogs against selected bacterial strains. The synthesized compounds are purified using high-performance liquid chromatography, and absorption, distribution, metabolism, excretion, and toxicity analyses are performed, including interaction profiling with over 370,000 bioactive compounds. The bacterial strains Staphylococcus aureus 10 and Pseudomonas aeruginosa 24 are used as test organisms. When combined with standard antibiotics, thiadiazine compounds significantly reduced the minimum inhibitory concentration. However, some analogs exhibited antagonistic effects, particularly against gentamicin and erythromycin. Direct antibacterial activity is limited, with compounds IJ26 and IJ28 showing the most notable effects. These findings suggest that thiadiazine analogs may potentiate antibiotic activity, although further studies are needed to fully understand their biological interactions and mechanisms of action.

Capture of greenhouse gases, especially CO₂, can reduce the effects of global warming and generate valuable minerals as feedstock for industry. Herein, the mineral products formed by capture of atmospheric CO₂ by potassium hydroxide (KOH) in aqueous, aqueous-ethanol, and aqueous-acetone solutions, and aqueous-acetone enriched using solid CO₂ are studied. A multimodal analysis combining single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), with Pawley and Rietveld refinements, and 850 MHz, 1 GHz, and 1.2 GHz ¹H, as well as ¹³C, and ³⁹K nuclear magnetic resonance (NMR), is used to analyze the composition of the mineral products. SCXRD identifies KHCO₃ in space group P2₁/n (transformable to P2₁/a) as a product from all reactions. PXRD and NMR data show the presence of both crystalline and amorphous phases in products, predominantly as mixtures of KHCO₃ and K₂CO₃ and its hydrates, with KOH as a minor component, except for aqueous-ethanol which gives KHCO₃ in high purity. Analysis of complex ¹H NMR data is aided by 2D nuclear Overhauser effect spectroscopy (1 GHz), which characterizes COH···OC interactions. Revealing K₂CO₃ hydration is aided by deconvolution of ultrahigh-field 28.2 T (56 MHz) ³⁹K spectra. This multimodal approach provides new insights into the speciation of potassium minerals from CO₂ capture.

Rare earth elements (REEs) are important topics and receive considerable attention, because of their unique properties, high economic value and are widely applied in various fields. Gadolinium is an REE, commonly used as a contrast agent for magnetic resonance imaging. However, its presence is still mixed with other REE like samarium and lanthanum so it's necessary to separate gadolinium from the mixture. The purpose of this research is to separate gadolinium from samarium and lanthanum and to determine the optimum conditions of various parameters that affect their separation. This separation is carried out by emulsion liquid membrane method using tributyl phosphate extractant, span-80 and tween-80 surfactants, kerosene solvent and nitric acid as internal and external phases. Parameter optimization is carried out with Box-Behnken design (BBD) which can predict the optimum value efficiently. The results are analyzed using visible spectrophotometer with alizarin red sulfonate. In this research, gadolinium is successfully separated from samarium and lanthanum with optimum conditions: surfactant concentration 4.2%, ligand concentration 1.4%, internal aqueous concentration 2.3 M, and external aqueous pH 1. The results obtained gadolinium with a value of %E and %S being 84.18% and 89.24%, while the recovery and purity are 75.12% and 22.59%.

The Front Cover image illustrates an innovative synthesis of combined Brønsted and Lewis acid sites in SBA-15 mesoporous material that allows catalysing selective dehydration of hexoses to furans. Well dispersed Zr and Sn species incorporated onto the mesoporous support, followed by a sulfation procedure generates an enhanced catalyst with adequate B/L acid ratio for the selective dehydration of fructose-to-HMF in a biphasic medium. This Artwork symbolizes how concentrated solution of fructose is converted to HMF over the efficient SO₄/Sn-Zr-SBA-15 catalyst. More information can be found in the Research Article by Marcelo E. Domine, María Laura Martínez, and co-workers (DOI: 10.1002/open.202400480). Cover design: M.L. Martínez.

Water electrolysis for hydrogen and oxygen production has considerable potential for sustainable development as a clean energy source.Herein, a controllable and reliable method is demonstrated for the doping of mesoporous TiO₂ with nickel oxide x-NTO for an efficient oxygen evolution reaction. An acetic acid-assisted soft-template method using block copolymer polyvinylpyrrolidone as a structure-directing agent successfully synthesizes x-NTO with uniform large mesopores. Compared to the pure TiO₂ mesoporous (0-NTO), all the x-NTO exhibit greatly enhanced oxygen evolution reaction (OER) activity. Furthermore, the percentage of nickel oxide greatly impacts the OER performance of x-NTO catalysts, and the ≈3.0 wt% (3.0-NTO) shows the greatest activity for OER, due to a 0.270 V decrease of the onset potential, while demonstrating an overpotential (η) of 340 mV at 10 mA cm^-2 in 1 M KOH solution and higher mass activity (66.50 mA mg^-1). Likewise, the 3.0-NTO electrode is very durable and engaged during electrolysis, without any obvious current declines or potential wandering seen during 12.0 h of electrolysis, confirming the 3.0-NTO's potential to serve as an electrocatalyst in energy conversion technologies.

Cyanoacetamidobetaine, or N-cyano-2-(trimethylammonio)acetaminide, is obtained from a reaction of sodium dicyanamide and betainium chloride in an aqueous solution after 4 h at 30 °C. By adding DCM, single-crystals suitable for diffraction experiments are obtained. The compound crystallizes in the monoclinic space group P2₁/c with lattice parameters a = 7.3365(2) Å, b = 8.8351(3) Å, c = 11.0977(4) Å, and β = 91.948(2)°. The unexpected reaction product comprises a trimethylammonium head group linked via a methylene bridge to a negative cyanoacetaminide moiety, highlighting the thermodynamic preference for intramolecular charge compensation over salt formation of betainium with dicyanamide. The findings are supported by infrared and nuclear magnetic resonance spectra and density functional theory calculations.

Developing stable and reusable biocatalysts is crucial for improving the sustainability of industrial processes, including enzymatic deinking. In this article, cellulase is immobilized onto chitosan-polyvinyl alcohol (Cs/PVA/Ga) biopolymer beads using glutaraldehyde cross-linking, creating a durable and recyclable catalytic system. Scanning electron microscopy revealed a bead-like structure, and fourier transform infrared spectroscopy spectra confirmed successful enzyme incorporation without compromising the polymer's integrity. Immobilization shifted the optimal activity of cellulase from pH 5 to pH 8 and raised the temperature optimum from 50 °C to between 60 and 70 °C, indicating improved catalytic stability. Kinetic studies showed a decrease in Km from 0.75 mM for the free enzyme to 0.4mM for the immobilized form, suggesting increased substrate affinity. Thermal stability tests revealed cellulase@Cs/PVA/Ga maintained over 83% of its activity at 80 °C for 60 min, compared to only 50% for the free enzyme. The immobilized cellulase demonstrated 90% activity retention after seven reuse cycles. Biodeinking experiments with recycled pulp evidenced optimal cellulose and hemicellulose retention with a 5% enzyme dosage, while effluent analysis showed enhanced removal of ink residues with the immobilized enzyme, highlighting the ecoefficient potential of this approach for sustainable paper recycling.

Many biomolecular studies start with labeling a protein with a fluorescent label, spin label, or chemical label. The methanethiosulfonate (mts)-linking group suffers from a hitherto not-understood side reaction that leads to label-dimerization instead of the desired linking of the label to the cysteine of the protein. Using electron paramagnetic resonance and mass spectrometry, the side reaction is studied for the MTSL ((1-oxyl-2,2,5,5-tetramethyl-Δ-3-pyrroline-3-methyl) methanethiosulfonate) and the (1-oxyl-2,2,5,5-tetramethylpyrrolidin-3-yl) methyl methanethiosulfonate label. At 0.1 mM MTSL, substantial dimer formation is observed within the first 5 h. The reaction pathway is elucidated and the structure of the disulfide-linked asymmetric dimer is suggested. The reaction seems not to involve the nitroxide or a radical reaction, suggesting that this reaction could also occur for other mts-linked functional or labeling groups.