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Three new compounds, kouytchin A (1), kouytchin B (2), and 2,4,5,10-tetramethoxydibenzo[1,4]dioxin (3), along with nine known compounds (4-12), were isolated and purified from the ethyl acetate extract of Hypericum kouytchense H Lév. The known compounds were identified as uraloidin A (4), uralione D (5), biyoulactones B (6), xanthone derivatives (7-11), and 3-hydroxy-1,4,7-trimethoxydibenzofuran (12). The structures of new compounds were elucidated based on comprehensive spectroscopic analysis, including 1D NMR (¹H, ¹³C and DEPT), 2D NMR (HMBC, COSY and HSQC), HRMS, and electronic circular dichroism (ECD). Furthermore, compounds 4 and 5 exhibited potent cytotoxic activity against the gastric cancer cell MKN-45, with half-maximal inhibitory concentration (IC₅₀) values of 16.00 ± 0.86 µM and 18.47 ± 0.95 µM, respectively. These findings enrich the phytochemical knowledge of H. kouytchense and highlight the potential of its constituents as leads for anticancer drug discovery.

Recently, there has been growing interest in inorganic halide perovskites as a reliable and clean alternative to lead-based hybrid perovskites. However, the fact that there is still a limited comprehensive first-principles study about $$$$ (A = P, As, Sb; X = Cl, Br) compounds hinders their exploring them for photovoltaic and thermoelectric applications. To address this gap, the present work aims to systematically study the structural, electronic, optical, and thermoelectric properties of $$$$ perovskites to identify possible sustainable energy solutions by replacing lead with other elements. Density functional theory (DFT) within the full-potential linearized augmented plane wave plus local orbitals (FP-LAPW+lo) method was implemented in the WIEN2k code. The Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) and the modified Becke–Johnson (mBJ) potential were used to produce accurate electronic and optical results, respectively, while thermoelectric properties were studied using Boltzmann transport theory via the BoltzTraP code. All $$$$ compounds crystallize in a cubic Pm-3m structure and have direct bandgaps at the $$ point, making them suitable for UV–visible light absorption. Optical investigation showed large absorption peaks for $$$$, while thermoelectric calculations showed $$$$ with the highest power factor in both p-type and n-type regions. These results revealed a correlated optoelectronic behavior and thermoelectric response throughout this series. In summary, $$$$ perovskites exhibit complementary optical and thermoelectric properties, making them potential candidates for future optoelectronic and sustainable energy alternatives.

This study reports the phytochemical composition and multifunctional biological activities of Astragalus lusitanicus Lam. subsp. orientalis. Ethanol and water extracts were prepared using ultrasonic-assisted extraction and evaluated for total phenolic and flavonoid contents, as well as their antioxidant, antimicrobial, and enzyme inhibitory properties. LC–ESI–MS/MS analysis revealed major phenolic constituents, including hesperidin, caffeic acid, protocatechuic acid, and quercetin. The water extract exhibited higher total phenolic (40.36 mg GAE/g) and flavonoid (12.39 mg RE/g) levels, correlating with superior antioxidant performance in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) assays. In contrast, the ethanol extract demonstrated stronger inhibitory effects against acetylcholinesterase, tyrosinase, and α-amylase. Antimicrobial assays (disc diffusion and broth microdilution) showed that the ethanol extract exhibited significant activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Listeria monocytogenes, while the water extract displayed moderate inhibition. These findings show that the extracts display measurable in vitro antioxidant, antimicrobial, and enzyme inhibitory activities. The combined presence of various phytochemicals may contribute to the observed activities; however, potential applications would require additional mechanistic, toxicity, and formulation studies. This work provides new chemical and biological insights into an underexplored Astragalus taxon, contributing to the discovery of natural bioactive agents relevant to medicinal chemistry.

In the present work, we synthesized a novel library of indoline-pyrazine hybrids involving Buchwald coupling, Suzuki–Miyaura coupling, and Ulmann reactions. The new analogues were screened for their in vitro anticancer activity against MCF-7 and MDA-MB-231 cell lines, using doxorubicin as a reference, by the MTT test. Compound 7d displayed potent activity against both cell lines with IC₅₀ values of 8.72 ± 0.88 µM and 9.54 ± 0.85 µM, respectively. Compound 7c was observed to be the second most active compound with an IC₅₀ value of 10.45 ± 1.02 µM and 9.59 ± 1.08 µM. Compound 7a showed promising activity with an IC₅₀ value of 11.19 ± 1.03 µM and 12.34 ± 1.07 µM. Compound 7 g presented a good activity with an IC₅₀ value of 14.54 ± 1.03 µM and 15.35 ± 1.05 µM. Molecular docking studies performed against the crystal structure of epidermal growth factor receptor (EGFR) with potent ligands 7c and 7d demonstrated a promising docking score and meaningful binding interactions, especially H-bonds. Predicted ADME properties presented their favorable drug-like properties.

Identification of novel drugs for the neurodegenerative diseases such as Alzheimer's and Parkinson's are complex due to the involvement of more than one distinct cause and multiple disease mechanisms with multiple drug targets. Numerous target-specific chemical or biologic drugs, proposed earlier, were either abandoned due to their limited potency to a single mechanistic target enzyme or failed in clinical trials due to adverse side-effects and impaired blood–brain barrier (BBB) efficacy. This work focuses on a strategically designed database of quinazolinone derivatives and performed a detailed ADMET screening and sequential molecular docking toward the simultaneous inhibition of three therapeutic targets of Alzheimer's disease (AD) namely, acetylcholinesterase, butyrylcholinesterase, and β-secretase. Molecular dynamics simulation (MD simulation) was conducted for 100 ns on the best-docked poses of potential lead compound QNZ14 to analyze stability and interaction at the catalytic active site. The MD simulation trajectories, including RMSD, root mean square fluctuation (RMSF), and ligand–protein interaction were analyzed to interpret the stability. The effort has successfully identified a novel inhibitor of AD pathogenesis with “multi-targeted efficacy”. This finding opens the door for further research into the lead compound as potential therapeutics for the efficient triple inhibition of the three crucial enzymes of amyloid-based and cholinergic mechanisms for AD pathogenesis.

Effective menstrual hygiene management (MHM) is crucial for adolescent girls and women, yet conventional sanitary napkins present health, environmental, and cost-related challenges. This study reports the synthesis of pH-responsive superabsorbent polymers (SAPs) via free radical copolymerization of selected monomers for seven formulations followed by microencapsulation with n-eicosane (mSAPs) for application in hygienic textiles. The polymers were characterized using FT-IR spectroscopy, thermogravimetric analysis (TGA), and particle size analysis. All formulations (SAP/mSAP-1C to SAP/mSAP-7C) were evaluated for free swell capacity (FSC), absorption under load (AUL), wet back, wicking height, pH responsiveness, and reusability. The optimized mSAP formulation exhibited excellent swelling capacity (FSC: 106.55 g/g) and minimal wet back (0.26 g), outperforming commercial products in absorbency and comfort. AUL values exceeded 98%, confirming strong gel stability. Effluent analysis (hardness, alkalinity, chloride, COD, BOD) confirmed acceptable discharge quality. Safety assessments—and HRIPT (sample size n = 105)—showed no skin irritation or sensitization in normal and sensitive skin. Although absorption decreased in saline solutions due to ionic charge screening, the prepared SAPs and mSAPs demonstrated significant potential for hygienic applications. Despite their promising performance, the non-biodegradable nature of these polymers highlights the need for eco-friendly modifications and sustainable disposal strategies.

Thermodynamic and structural effects of a binary system with ethyl lactate (EL) and higher 1-alkanols were studied using experimental and computational approaches. Hence, density (ρ), speed of sound (c), and refractive index (n_D) for (EL + 1-heptanol, 1-octanol, and 1-nonanol) binary systems were measured at different temperatures and at 0.1 MPa. From these experimental data, thermodynamic properties: excess volume (V^E), isentropic compressibility (k_s), excess isentropic compressibility $$, and excess refractive index $$ were calculated. Further, the Redlich–Kister polynomial equation was used to fit the excess properties, and the resulting analysis focused on examining structural effects and interactions at the molecular level. Knowledge of these molecular interactions will allow us to develop more effective separation strategies, improve process efficiency, and reduce energy consumption of industrial separation units. Moreover, FT-IR spectra were obtained for both pure components and their mixtures at various mole fractions, and density functional theory (DFT) calculations were carried out for three sets of binary systems using the ADF 2020.102 package to discern the type of interactions that are prevailing between liquid molecules. The excess volume and excess isentropic compressibility were positive, whereas the excess refractive index was negative for all the binary systems.

Activated carbon derived from spent coffee grounds is synthesized by chemical activation with a defined KOH concentration and varying urea concentration. The effects of urea concentration on porosity development, electrical conductivity, and charge storage performance are systematically evaluated using SEM, Raman, XRD, BET, TEM, and electrochemical characterization methods. The sample activated with a 1:2:1 of carbon:KOH:urea ratio (ACKU1) exhibits the highest specific surface area (S_BET = 2805 m² g⁻¹) and the most favorable pore structure, combining micro- and mesoporosity, whereas the sample without urea, 1:2 of carbon:KOH ratio, shows a much smaller specific surface area (S_BET = 1357 m² g⁻¹). The electrochemical characterization of ACKU1 in the three-electrode configuration reveals that it exhibits the highest specific capacitance (C_g = 270 F g⁻¹ at 5 mV s⁻¹ and C_g = 293 F g⁻¹ at 0.5 A g⁻¹). Furthermore, the ACKU1 symmetric supercapacitor exhibits a C_g^cell of 54.2 F g⁻¹ at 0.5 A g⁻¹, retaining 95% of its capacitance after 10,000 charge-discharge cycles at 4 A g⁻¹, with energy and power densities of 7.5 Wh kg⁻¹ and 58 kW kg⁻¹, respectively. These results highlight the synergistic effect of KOH and urea in producing high-performance, sustainable carbon materials from biomass residues for energy storage applications.

We developed a photoinduced 6π-electrocyclization method to synthesize a series of trans/cis-benzo[f,h]isoquinolin-1(2H)-ones. Trans-2-methyl/2,4a-dime thyl-4a,12b-dihydrodibenzo[f,h]isoquinolin-1(2H)-ones (trans-2a–2h, trans-2i–2l) and trans-3,10b-dimethyl/3-methyl/10b-methyl-4a,10b-dihydrobenzo[f]isoquinolin-4(3H)-ones (trans-4a–4i, trans-4j) were obtained by irradiating 3-([1,1′-biphenyl]-2-yl)-1-methyl/1,4-dimethylpyridin-2(1H)-ones (1a–1h and 1i–1l) and (E)-1,4-dimethyl/1-methyl/4-methyl-3-styrylpyridin-2(1H)-ones (3a–3j) under UV light, respectively. In the presence of HCl, cis-2a–2h and cis-4a–4i were synthesized under the same conditions of trans-2a–2h and trans-4a–4i. Cis-2i–2l and cis-4j were prepared by heating trans-2i–2l and trans-4j in DMF at 110°C. The transformation proceeds via a photo 6π-electrocyclization followed by a [1,5-H] shift, enabling the efficient construction of dearomatized trans/cis-benzoquinolin-2(1H)-one scaffolds with high atom economy and effective bond formation. This method provides a metal and additive-free strategy for the concise synthesis of chemoselectively trans/cis-benzoquinolinone frameworks.