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A small molecule library of nicotinamide derivatives synthesized and characterized their structure by interpretation of ¹H NMR, ¹³C NMR, and Mass spectral data. The new molecules were screened for their in vitro anticancer activity against human breast (MCF-7) and cervical (HeLa) cell lines by using Doxorubicin as standard reference. Pyridine linked nicotinamide derivatives displayed potent activity against both the cell lines. The trifluoromethyl substituted pyridine analogue demonstrated outstanding activity with IC₅₀ value of 8.70 ± 0.23 µM and 8.97 ± 0.31 µM against MCF-7 and HeLa cell lines respectively, with respect to Doxorubicin IC₅₀ value of 9.06 ± 0.36 µM (MCF-7) and 9.17 ± 0.39 µM (HeLa). The compound 6 with thiomethyl group displayed activity with IC₅₀ value of 9.01 ± 0.38 µM and 9.82 ± 0.41 µM against MCF-7 and HeLa cell lines correspondingly. The methyl substituted compound 5h  displayed encouraging activity with IC₅₀ value of 10.47 ± 0.41 µM (MCF-7) and 11.87 ± 0.45 µM (HeLa). Molecular docking study performed using potent molecules 5h , 5i, and 6 against estrogen receptor alpha (PDB ID: 3ERT), obtained highest docking score value for ligand 5i (9.5 kcal/mol). The predicted ADME of compounds indicated their drug-like characteristics.

Recently, there is an interesting report (J. Am. Chem. Soc. 2020, 142, 13090–13101) on the photoinduced mechanism for the H₂ dissociation studied through a simple Au₆-H₂ model. However, the adsorption energy between the Au₆ and H₂ is only 0.25 eV, and the H─H bond length is only slightly longer. Based on the structural framework of the triangular Au₆, we have investigated the adsorptions of H₂ on the transition metals (TM = Ni, Cu, and Zn group elements) and revealed the differences in activation of H₂ on TM atoms. The results confirm that the activation of H₂ by the Au₅Ni cluster is the best in terms of the stability and adsorption energy (0.89 eV), where the H─H stretching frequency also has a very obvious redshift compared with the free H₂. The AIMD simulations show that the Au₅Ni-H₂ maintains an excellent thermal stability even at 500 K. The density of states, molecular orbitals, NCI-RDG, and bond order analyses indicate that the Ni∙∙∙H₂ and Au∙∙∙H₂ are rather strong, directly showing the bonding interactions. By studying H₂ adsorptions on TM atoms, one can obtain fundamental insight into elementary steps that take place on catalytically active surfaces.

An efficient method offering high convenience and sustainability, showcasing the potential for the green synthesis strategies has been developed. The protocol presents a straightforward, environmentally friendly approach for construction of substituted 3,4-dihydro-2H pyrroles in an aqueous ethanol that describes a one-pot multistep reaction sequence, initiated with a Claisen–Schmidt Condensation, followed by the Michael addition of nitro methane to chalcone, next to line being reduction an intramolecular cyclization steps to yield the desired product in moderate to higher yields. Underscoring the effectiveness of the sequence, the biological activities has also been evaluated for the compounds. Preliminary studies indicating promising antibacterial and antifungal properties, make these compounds significant for further pharmaceutical development. The use of ethanol as a green solvent in the one-pot pyrroline synthesis process underscores the importance of environmentally friendly solvents, significantly reducing the environmental impact and aligning with the principles of sustainable chemistry. The green synthetic strategy combined with the notable biological activities demonstrates the dual benefit of this research, contributing both to the field of green chemistry and to the therapeutic drug discovery.

Photocatalytic technology is one of the most promising technologies for wastewater treatment. In this study, an Ag₂S/Ag₃VO₄ heterojunction was prepared by combination of in-situ partial sulfidation and hydrothermal technologies. The photodegradation results demonstrated that the highest removal efficiency for RhB was 96% for 40%-Ag₂S/Ag₃VO₄ heterojunction in 6 min under visible light irradiation, which was obviously superior to that of pure Ag₃VO₄ (∼46% in 6 min) and Ag₂S (∼1.8% in 6 min) photocatalysts. As manifested by the DSR experiment, the improved photodegradation ability of the 40%-Ag₂S/Ag₃VO₄ heterojunction was attributed to enhanced light absorption and excellent electron-hole pairs separation induced by the formation of a Z-scheme heterojunction between Ag₂S and Ag₃VO₄. The active species capture experiments confirmed that h⁺ plays the important role for degradation of RhB. Furthermore, the results of photodegradation cyclic test revealed that the 40%-Ag₂S/Ag₃VO₄ heterojunction owned an excellent photocatalytic stability.

A novel synthetic route for the direct synthesis of 4,5-diarylisoxazoles is less common. A facile and efficient synthesis of 4,5-diarylisoxazole derivatives via I₂-mediated reaction from α,β-chalcone epoxides under mild and metal-free conditions is developed. This protocol enables facile access to 4,5-diarylisoxazole derivatives in good to excellent yields using EtOH/H₂O (1:1) solvent at 80 °C temperature. The structural integrity of the compounds was confirmed by ¹H, ¹³C, IR, CHNS, GC-MS, and SC-XRD analysis.

Diseases such as injury, stenosis, and tumors of the long trachea usually require the removal of the affected part of the trachea. There is an urgent need to implant tracheal stents as substitutes in clinical practice. In this paper, Mg²⁺ was first doped into hydroxyapatite (HA) matrix by hydrothermal synthesis and then mixed with gelatin sodium alginate (Gel–SA) double network crosslinked hydrogel to prepare gelatin sodium alginate magnesium doped hydroxyapatite (Gel–SA–MgHA) composite biomaterial ink. The trachea stent was prepared by 3D bioprinting technology and its physicochemical, mechanical, and biological properties were systematically evaluated. Due to the large number of hydrophilic groups on the surface of the HA matrix, the addition of MgHA improved the hydrophilicity of tracheal stents. The mechanical properties of the stent first increase and then decrease with the increase of MgHA content. When the MgHA content is 4 wt%, the tracheal stent has the optimal mechanical properties. In vitro cytology experiments have confirmed that the four stent materials have good cell compatibility and proliferation characteristics. Overall, Gel–SA–4MgHA has the best mechanical and cytological properties, and has certain potential in the clinical application of tracheal stents.

A new and effective metal-free method for synthesizing 3-aryloxindole derivatives through hypervalent iodine(III)-mediated 1,2-aryl migration in 3-arylideneindolin-2-ones is presented in this study. The reaction utilizes (diacetoxyiodo)benzene (DIB) in methanol to trigger skeletal oxidative rearrangement, resulting in the formation of all-carbon quaternary centers at the C3 position of oxindoles. This approach provides a mild and environmentally friendly alternative to traditional metal-catalyzed processes, offering broad substrate tolerance. Furthermore, this method provides a valuable synthetic route for constructing biologically significant 3-aryloxindole derivatives with potential pharmaceutical applications.

During CO₂ methanation, the generation of H₂O as a by-product can lead to its strong adsorption on the catalyst's active sites, potentially blocking them or altering the active phase, thereby degrading catalytic performance. To mitigate this inhibition effect by water, we introduce a hydrophobic surface via stearic acid treatment to rapidly remove H₂O formed during CO₂ methanation over NiAl mixed metal oxide (MMO)-derived catalysts. The crystal structure of NiAl MMO and the average Ni particle size of ∼13 nm remain unaltered by the hydrophobic treatment. The NiAl catalyst treated with an optimal concentration of stearic acid shows a nearly doubled CO₂ conversion of 61.4% at 275 °C, compared to the pristine catalyst, and this high activity is sustained for over 100 h without deactivation. However, excessive stearic acid coverage inhibits CO₂ adsorption significantly, causing a sharp drop in CO₂ conversion to 10.8%. This study demonstrates that hydrophobic surface modification can effectively ameliorate catalyst deactivation due to by-product H₂O, which could be applied to many other catalytic reactions where H₂O acts as an inhibiting by-product.

New conformationally-restricted steroids were synthesized by incorporating a spiranic heterocyclic motif at the C-17 position, using trans-androsterone, trans-dehydroandrosterone, and estrone as starting materials. A cyclocondensation process with o-disubstituted aromatic bis-nucleophiles enabled the modification of the structure. In silico calculations were employed to predict the diastereoselectivity and the assignment of the new chiral center stereochemistry. Spiranic derivatives were evaluated in vitro for antiproliferative activity against six human tumor cell lines, with benzoxazolines showing the highest activity. Derivatives of estrone exhibited greater potency than those of androsterone, being up to 50-fold more active than abiraterone, a steroidal anticancer drug. Live cell imaging of the lead compound combining estrone and a benzimidazoline residue revealed apoptotic events such as membrane blebbing, nuclear condensation, and cell shrinkage, suggesting potential utility for therapeutic applications.

In this study, we synthesized the citric acid-modified jackfruit leaf powder (CIJLP) to comprehend the adsorption behavior and mechanism of Pb²⁺ and Cd²⁺ adsorption in simulated aqueous solution. This investigation suggested that CIJLP shows 125 mg/g of maximal adsorption capacity for Pb²⁺, which is nearly 1.6 times more than Cd²⁺ (∼77 mg/g). The optimum pH values for adsorption of Pb²⁺ and Cd²⁺ were determined to be 6.0 and 5.0, respectively. The CIJLP was characterized using FT-IR, FESEM–EDX, and XPS analyses. The FT-IR and EDX analyses revealed the crucial role of oxygen-containing functional groups onto CIJLP, which substantially contributed to the heavy metal removal with extremely high adsorption capacities. Based on regression coefficient and RMSE values, adsorption behavior of Cd²⁺ and Pb²⁺ onto CIJLP were best fitted by Freundlich and Langmuir isotherm models. Moreover, kinetic data was better represented by the pseudo-second-order model. Consequently, the heavy metal adsorption onto CIJLP was chemisorption on homogenous monolayer. It was primarily controlled by cation exchange and surface precipitation mechanism. Due to its significantly efficient adsorption for Pb²⁺ and Cd²⁺, as compared to the other biowaste-based adsorbents, CIJLP can be utilized industrially and is socially acceptable as an adsorbent for efficient removal of these toxic ions from an aqueous solution.