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Novel purine-based piperazine analogs were rationally designed and synthesized using fluoro-substituted benzoyl chloride as a key intermediate. The synthesized compounds were characterized and evaluated for their potential anti-tubercular activity. In vitro biological screening revealed that compounds S1C, S1D, and S1F exhibited significant antimycobacterial activity, with MIC values ranging from 8.5 to 18.8 µg/mL. To gain molecular insights into their mechanism of action, molecular docking studies were performed against UDP-N-acetylenolpyruvoylglucosamine reductase (MurB) from Mycobacterium tuberculosis. The docking results demonstrated favorable binding affinities, characterised by key hydrogen bonding and hydrophobic interactions at the active site. Additionally, 100 ns molecular dynamics simulations were conducted to assess the stability of the protein–ligand complexes. ADME profiles were predicted using the PreADME server, suggesting acceptable pharmacokinetic and pharmacodynamic properties. Overall, the biological evaluation, computational modeling, and favorable ADME profiles indicate that compounds S1C, S1D, and S1F are potential candidates for anti-tubercular drug development.

Esterification reactions are essential for producing many commercially valuable chemicals. Although waste copper slag poses a growing environmental concern, its high content of metal oxides (FeO, SiO₂, Al₂O₃, CaO, and residual Cu) remains underutilized as a catalytic resource. The study addresses research gap by exploring copper slag as a sustainable catalyst for esterification, aiming to enhance catalytic efficiency while promoting waste valorization. Vanadium pentoxide (V₂O₅) supported on wet copper slag (V₂O₅/Wet Cp-Sl) was synthesized using the impregnation method and employed as a heterogeneous catalyst for esterification reactions aimed at producing biofuels, flavors, fragrances, surfactants, and biopolymers. The catalysts were thoroughly characterized using HR-TEM, XRD, XPS, ATR-FTIR, BET, EDX-mapping, TGA, and ICP-AES techniques. Esterification of oleic acid with methanol exhibited optimal catalytic performance at a 10 wt% V₂O₅ loading on Wet copper slag, which showed 92.4% yield. The activation energy was calculated to be 13.4 kJ/mol, suggesting enhanced catalytic efficiency. The incorporation of V₂O₅ led to the formation of Fe³⁺, Al³⁺, and Si–O–M species, strengthening metal–support interactions. The presence of redox-active species such as V⁴⁺ and Fe²⁺ further contributed to improved catalytic activity. ATR-FTIR studies identified the nature of active sites, while kinetic analysis evaluations confirmed a reduction in activation energy.

Pinecone performance was investigated for Rhodamine B (RhB) adsorption and experimental design was used for optimization of removal conditions. The characterization of pinecone adsorbents (PCA) were carried out with the Brunauer-Emmett-Teller (BET), Fourier transform infrared spectra (FTIR), and scanning electron microscopy (SEM) analysis before and after adsorption. The effects of initial RhB concentration (20-120 mg L⁻¹), pH (2–12), temperature (298–318 K), and contact time (10-240 min) on the adsorption were investigated. The removal efficiencies of the 20 mg L⁻¹ initial RhB concentration were found to be 72.16%, 75.85%, and 88.95% at temperatures 298 K, 308 K, and 318 K, respectively. The removal process of RhB on PCA was evaluated with isotherm, kinetic, and thermodynamic results. Freundlich isotherm model was provided the best fit to the experimental data compared to Langmuir, Temkin, and Dubinin-Radushkevich (D-R) models. The maximum adsorption capacity (q_max) was reached 96.956 mg g⁻¹ at 318 K. The pseudo-second-order (PSO) model was showed the highest coefficients (R²), indicating its suitability for describing this adsorption process. Thermodynamic parameters for 40 mg L⁻¹ initial RhB concentration at 318 K were revealed negative values of Gibbs free energy (-2975.63 J mol⁻¹), and positive values of enthalpy (38052.73 J mol⁻¹), and entropy (129.02 J mol⁻¹K⁻¹), confirming that process was spontaneous with endothermic nature and the activation energy was calculated to be 17.19 kJ mol⁻¹. Initial RhB concentration (20-120 mg L⁻¹), temperature (298 K-318 K), and contact time (10-240 min) parameters were selected as independent variables and removal percentages of RhB were used as response values. The reliability of optimization studies was evaluated with R², adjusted R² and predicted R² values which were obtained the 0.9873, 0.9759, and 0.8852, respectively.

A sustainable and metal-free sulfur-doped reduced graphene oxide (S@RGO) nanocomposite was synthesized using Moringa oleifera leaf extract to evaluate its efficiency in photocatalytically degrading ciprofloxacin (CIP). The efficient integration of sulfur into the reduced graphene oxide structure was confirmed by sharp and well-defined peaks from powder x-ray diffraction (XRD). Energy-dispersive x-ray spectroscopy (EDX) disclosed the elemental composition. Fourier-transform infrared spectroscopy (FT-IR) discovered important functional groups. Under visible light irradiation, the porous S@RGO demonstrated exceptional photocatalytic activity due to its large specific surface area of 223 m²/g and strong structural integrity. Notably, a degradation efficiency of 97.8% was attained with just 20 mg of S@RGO needed to break down 50 mL of 10 mg/L CIP in 120 min. This high performance is attributed to the synergistic effects of sulfur doping and porosity, which enhance visible light absorption and promote efficient charge carrier separation. The proposed mechanism involves visible-light-driven photocatalytic degradation. These findings highlight the potential of bioengineered S@RGO as a green, sustainable photocatalyst for the removal of pharmaceutical contaminants from aqueous environments.

In recent years, many researchers have studied the influence of modifying components on catalytic performance by adding them to ethylene oligomerization systems. This paper studied the effect of eight phosphine-containing modifiers on the catalytic performance of the chromium-based silicon-bridged diphosphine (PNSiP)/methylaluminium system. Modifiers like diethylchlorophosphine oxide, diphenylchlorophosphine oxide, triphenylphosphine, trimethylphosphine, triethylphosphine, phosphorus trichloride, diphenylphosphine chloride, and diisopropyl phosphorus chloride showed a significant influence on the catalytic activity of the catalytic system and the selectivity of 1-octene. When the molar ratio of diethylchlorophosphine oxide to chromium increased to 0.6, the catalytic activity increased from 7.39 × 10⁶ to 11.75 × 10⁶ g/ (mol Cr·h), exhibiting the most remarkable promotional effect. When the molar ratio of diphenylphosphine chloride to chromium increased to 0.6, the selectivity of 1-octene increased by 11.89%. Based on the results of electron paramagnetic resonance (EPR) and ultraviolet–visible spectrum (UV–Visible) analysis, we inferred that diethylchlorophosphine oxide was coordinated with the chromium active center through a phosphine-oxygen bond, which improved the catalytic activity of the reaction system. Furthermore, a possible reaction path between diethylchlorophosphine oxide and the chromium active center has been proposed, which is expected to provide a more economical and feasible strategy for the optimization of selective ethylene tetramerization systems.

The elimination of toxic synthetic dyes from wastewater remains challenging due to their remarkable stability and resistance to conventional treatment methods. Catalytic decolorization using sodium borohydride NaBH₄ has emerged as a fast and efficient strategy for transforming these persistent dyes into less harmful products, yet the development of green and sustainable catalysts with high activity, long-term stability, and broad applicability toward diverse dye pollutants remains a critical priority. This study reports the use of biogenically synthesized silver nanoparticles anchored on microcrystalline cellulose, via a mint extract-mediated route, as an efficient catalyst for the decolorization of cationic and anionic dyes. Characterization by XRD, FTIR, XPS, UV–vis DRS, SEM–EDS, and TGA confirmed successful nanoparticle formation, well-distributed morphology, and enhanced thermal stability of the composite compared to pristine MCC, with uniformly dispersed AgNPs of 5–10 nm anchored on the MCC surface. The catalytic performance of MCC@AgNPs was evaluated for the reduction of methylene blue (MB), methyl orange (MO), and allura red (AR), in the presence of sodium borohydride. Kinetic studies revealed the highest apparent rate constant for MB (Kapp = 0.0107 s⁻¹), achieving 98.77% removal in 330 s, followed by MO (K_app = 0.00819 s⁻¹, 95.51% removal in 390 s) and AR (K_app = 0.0066 s⁻¹, 94.40% removal in 480 s). The catalyst exhibited excellent recyclability, retaining over 90% efficiency for MB degradation after six consecutive cycles, demonstrating its potential as a cost-effective, and sustainable material for broad-spectrum dye remediation.

(+)-Lentiginosine is an indolizidine natural product, with its non-natural synthetic enantiomer being (−)-lentiginosine. Both (+)-lentiginosine and (−)-lentiginosine exhibit diverse bioactivities, such as antitumor, anti-HIV, and immunomodulatory effects, which have therefore attracted significant attention from synthetic chemists. This review focuses on the synthesis of lentiginosine and its epimers, covering the period from 2006 to 2025.

To systematically elucidate the factors governing the purity and morphology of calcium peroxide (CaO₂), single-factor experiments were conducted by regulating key synthesis parameters, including additives (EDTA and PAM) and reaction conditions. The results indicate that additive preregulation combined with controlled reaction conditions enables the targeted synthesis of CaO₂ with distinct morphologies. Under optimized conditions, the purity of EDTA-regulated CaO₂ (E-CaO₂) and PAM-regulated CaO₂ (P-CaO₂) reached 94.03 ± 0.29% and 94.15 ± 0.16%, respectively, accompanied by marked improvements in sludge dewatering performance. Scanning electron microscopy revealed that raw CaO₂ suffered from severe agglomeration, whereas E- CaO₂ formed well-dispersed needle-like rods and P-CaO₂ exhibited a three-dimensional wool-like structure. X-ray diffraction, Fourier transform infrared spectroscopy, and electron paramagnetic resonance analyses collectively confirmed the formation of crystalline CaO₂ with intact peroxide structures and effective hydroxyl radical (·OH) release capability. In sludge dewatering experiments, the addition of 0.7 g P-CaO₂ reduced the capillary suction time by 58.70 ± 5.35%. These findings demonstrate that morphology-controlled CaO₂ crystals represent a promising strategy for enhancing sludge dewatering efficiency and promoting sludge volume reduction.

The use of synthetic organic dyes for various industrial purposes contaminates water bodies, which is one of the prime causes for human health and environmental hazards. Dyes effluents released in water bodies not only affect the aesthetic value of water but also deteriorate aquatic life by increasing chemical oxygen demand and biochemical oxygen demand. Moreover, by entering in food chain it may severely affect human health by being genotoxic and carcinogenic. After conventional wastewater treatment methods, which are often, less effective, advanced oxidation processes including the photocatalytic degradation techniques have been emerged as efficient methods for dye degradation. Among the effective photo-catalyst, cobalt sulfide-based nanomaterials are emerging as one of the potential candidates for the photocatalytic degradation of organic dyes. The cost-effectiveness, high adsorption efficiency and reusability of cobalt sulfides are the additional support for their promising photocatalytic applications. The present manuscript describes the industrial contamination of organic dyes and their effect on human health and ecosystem. It systematically reviews various synthetic routes for cobalt sulfide and their composites for photocatalytic degradation of organic dyes. In addition, the manuscript elaborates on mechanistic insight, influencing factors and future aspects of cobalt sulfide-based nanomaterials in photocatalytic degradation of organic dyes.

Despite extensive investigation as biocompatible drug carriers, gelatin nanoparticles (GNPs) have not been thoroughly assessed for carrying chemically distinct cationic molecules such as acriflavine (ACF) and triethylenetetramine (TETA). In this study, we hypothesize that GNPs can effectively encapsulate ACF and TETA, forming stable delivery systems with distinct antibacterial and cytotoxic activities. ACF encapsulated in gelatin was prepared adapting desolvation technique. The procedure involved stirring of an aqueous solution of gelatin and ACF at room temperature, the pH was titrated to eight using NaOH followed by addition of ethanol. The resulting nanoparticles were treated with glutaraldehyde solution for stabilizing of formed nanoparticles and the cross-linking was achieved under stirring for 24 h. Finally, nanoparticles were decorated with TETA. An optimization study was conducted on TETA-ACF-GNPs using FT-IR in comparison to untreated gelatin and ACF, a new peak associated with the imine (C═N) formed bonds appears at 1643 cm⁻¹ providing evidence of the successful formation of gelatin-ACF conjugate. With respect to morphology, surface texture, and roughness, AFM result shows that the particle density of TETA-ACF-GNPs increased dramatically with a substantial decrease in particle size and a highly uniform surface topography, which are indicative of successful encapsulation. Higher entrapment efficiency and production yield were proved using UV–visible spectrophotometer. TETA-ACF-GNPs exhibit good antibacterial activity against Staphylococcus aureus and Pseudomonas auruginosa as well as less toxicity against normal human MRC-5 fetal lung fibroblast cells. Accordingly, gelatin might be useful as protein containers to be combined with ACF and TETA for improving pharmaceutical properties of drugs.