Search Results (67)

Background/Objectives: The rapid emergence of antimicrobial resistance has created an urgent need for new chemotypes with activity against bacterial, fungal, and mycobacterial pathogens. Rhodanine-based compounds are recognized as privileged scaffolds in medicinal chemistry because of their broad spectrum of biological activities, making them attractive candidates for the development of novel antimicrobial agents. Methods: A library of thirty-two novel rhodanine-based hydrazide derivatives (21–52) was synthesized by condensation of 5-ethoxymethylidenerhodanine derivatives with aromatic acid hydrazides and characterized by IR, ¹H NMR, and ¹³C NMR spectroscopy. Their drug-likeness and pharmacokinetics properties were evaluated using SwissADME, while antimicrobial activity was assessed against Gram-positive and Gram-negative bacteria, Candida spp., and both drug-susceptible and drug-resistant Mycobacterium tuberculosis strains using minimum inhibitory concentration (MIC) assays. Results: The synthesized compounds demonstrated selective activity against Gram-positive bacteria, whereas only limited activity was observed against Gram-negative species. The most potent derivatives (36, 40, 46, and 50) inhibited Micrococcus luteus with MIC values as low as 31.3 mg/L. Several compounds also demonstrated noteworthy antifungal activity, particularly against Candida parapsilosis (MIC = 15.6–31.3 µg/mL). Pyridyl-containing analogues displayed moderate antitubercular activity and, importantly, compounds 49 and 52 retaining activity against both drug-susceptible and drug-resistant M. tuberculosis strains. In silico analysis indicated favorable drug-like properties for most compounds, with good compliance with Lipinski’s rule of five and predicted oral bioavailability. Preliminary structure–activity relationship analysis revealed that a 3-phenylrhodanine core combined with para-halogen or para-nitro substituents significantly enhanced antimicrobial potency. Conclusions: The present study identifies rhodanine-based hydrazide derivatives as promising multifunctional antimicrobial scaffolds with activity against Gram-positive bacteria, pathogenic yeasts, and M. tuberculosis. The identified structure–activity relationships provide a rational basis for further lead optimization and support continued development of this chemotype as a potential source of new antimicrobial agents. Full article

The addition of potato and maize powders to wheat-based dough systems has been identified as a common practice for enhancing the dietary fiber content of cereal products. However, their product quality remains problematic due to inadequate comprehension of the manner in which starch granules regulate disulfide bond formation within wheat gluten proteins. In order to address this evident gap in the existing literature, this study investigated the effects of different starch granules—including potato, maize, and wheat—on disulfide bond formation of urea-solubilized glutenin (USG). The experimental results indicate that the optimal conditions for enhancing disulfide bonding in potato, maize, and wheat granules (from 0.2162 to 0.5319, 0.3502 and 0.9488 μmol/g, respectively) were as follows: a USG: granule ratio of 3:1 (w/w), a temperature of 45 °C for 30 min, a USG: granule ratio of 3:1 (w/w), a temperature of 35 °C for 120 min, a USG: granule ratio of 1:2 (w/w), a temperature of 25 °C, and a duration of 60 min, respectively. Under low-granule conditions, the possible mechanism was that all granules might leach out predominantly amylopectin (no blue color is observed when attached to an iodine solution) to facilitate disulfide bond formation of USG. Conversely, under high-granule conditions, the interaction between granule proteins may be excessive, potentially leading to the precipitation of amylose (dark blue color is observed when attached to an iodine solution). This process may result in a reduction in disulfide bond contents due to the competitive interaction of water molecules. Spectroscopic and structural analyses further indicated that the attenuation of the nuclear magnetic resonance (NMR) signal of C1 hydroxyl groups of amylopectin/amylose and peptide amide bonds of USG arose from physical entanglement based on the hydrogen bonds between them. Upon interaction between USG and potato/maize starch granules, the X-ray diffraction pattern of USG vanished, and the intramolecular β-sheet conformation was markedly diminished. Collectively, these findings provide a mechanistic foundation for the rational design and optimization of high-fiber, high-quality cereal-based food products. Full article

Background/Objectives: Long-acting injectable aqueous suspensions based on fatty acid prodrugs offer a compelling strategy for chronic disease management. However, the selection of optimal alkyl chain length remains largely empirical, as its influence on prodrug performance is highly system-dependent and lacks predictive guidelines. Methods: Three aripiprazole prodrugs with different alkyl chain lengths were synthesized and characterized using ¹H-NMR spectroscopy and single-crystal X-ray diffraction. A series of physicochemical assessments was performed, including melting point, solubility, lipophilicity, solid-state stability, and plasma stability. The prodrugs were subsequently formulated as aqueous suspensions, which were evaluated for particle size, morphology, release behavior, cytotoxicity, and cellular uptake. Finally, intramuscular administration in rats was carried out to investigate pharmacokinetic profiles and local tolerability. Results: Physicochemical characterization revealed that chain elongation progressively reduced the melting point, solubility, wettability, and solid-state stability of these prodrugs, whereas their flexibility, lipophilicity, and plasma stability correspondingly increased. After wet milling and intramuscular administration in rats, all suspensions sustained drug release for up to one month with good tolerability. Notably, the aripiprazole lauroxil formulation exhibited superior bioavailability and a shortened subtherapeutic interval, enabling the rapid attainment of therapeutic concentrations while effectively mitigating a prolonged pharmacokinetic tail. Conclusions: These findings reinforce the favorable profile of aripiprazole lauroxil as a lead candidate and demonstrate that isostructural packing facilitates the reliable prediction of chain length–property correlations across diverse fatty acid-prodrug systems, thus providing a valuable reference for rational alkyl chain selection in the design of fatty acid-based LAI suspensions. Full article

Alkali-activated concrete (AAC) offers the advantages of high mechanical strength and excellent corrosion resistance, making it a promising low-carbon material. However, its widespread application in practical engineering is severely limited by the serious issues of high shrinkage and susceptibility to cracking. To address the challenges, this work proposes incorporating superabsorbent polymers (SAPs) into AAC to mitigate its shrinkage problems. A comprehensive investigation is conducted on fresh, mechanical and shrinkage properties of SAP-modified AAC. The underlying shrinkage-mitigating mechanism is revealed through various tests including hydration heat, X-ray diffraction, scanning electron microscope (SEM), and nuclear magnetic resonance (NMR) analysis. Results indicate that SAP prolongs concrete setting times. With SAP addition, the overall porosity and weak interfacial transition zones are increased, leading to decreases in the compressive strength by approximately 6.9–20.2% at 28 d. Both splitting tensile and flexural strengths show varying degrees of improvement. Adding 0.1–0.3% SAP reduces the 3 d autogenous shrinkage by about 33.08–41.14%, and 56 d drying shrinkage by 12.4–32.7%. SAPs act as internal water reservoirs, regulating humidity and reducing AAC’s sensitivity to internal relative humidity. Furthermore, SAPs optimize AAC pore structure distributions, as revealed by SEM and NMR analyses. Given the impact of SAP dosage (0–0.3%), autogenous and drying shrinkage prediction models are respectively established based on CEB-FIP 90 and GL 2000 models, showing superior agreement between predicted results and test data, with all the fitting coefficients over 0.9. Full article

In this study, a new series of (E)-4-((2-(2-(4-amino-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetyl)hydrazono)methyl)phenyl 4-halogenobenzenesulfonates (3a–3d), where 3a = F, 3b = Cl, 3c = Br, and 3d = I, were successfully synthesized via a straightforward synthetic route. The structures of the obtained compounds were fully characterized and confirmed by spectroscopic techniques, including FT-IR, ¹H NMR, and ¹³C NMR, as well as LC-MS/MS analysis. 1,2,4-triazole-based hydrazone derivatives (3a–3d) were investigated using IR and NMR spectroscopy and DFT calculations. Intermolecular interactions, HOMO-LUMO, dipole moment, polarization, first-order hyperpolarizability, and molecular electrostatic potential studies on the molecules were examined. The HOMO and LUMO energy gap study supports the charge transfer probability in the molecules. These were conducted to investigate the reactivity and stability of heterocyclic molecules in bioactivity analysis. Electron density mapping within the molecular electrostatic potential plot and electrostatic potential representation within the iso-surface plot evaluated the concept of charge distribution in the molecule as nucleophilic reactions and electrophilic regions. The predicted nonlinear optical (NLO) properties of the molecules are much greater than those of urea. The results obtained from these investigations collectively provide evidence that the molecules possess nonlinear optical applications. Novel triazole–hydrazone-functionalized aryl sulfonate derivatives (3a–3d) were evaluated for their anticancer potential against a panel of brain and non-brain cancer cell lines. Compound 3b exhibited the most favorable overall biological profile, displaying potent activity against SH-SY5Y neuroblastoma (GI = 7.59 μM) and U87MG glioblastoma cells (GI = 13.85 μM), together with the lowest toxicity toward normal FL fibroblasts (GI = 62.02 μM). Compounds 3c and 3d demonstrated remarkable potency against IDHmut-U87 glioma cells (GI = 3.87 and 3.27 μM, respectively), although their selectivity toward cancer cells was limited. DNA degradation studies revealed substantial fragmentation, particularly in C6 and SH-SY5Y cells, while migration assays indicated reduced cellular motility. Molecular docking studies identified compound 3b as the strongest PI3Kα binder, supporting a possible. In addition, the antimicrobial activities of compounds 3a–3d were evaluated against selected Gram-positive and Gram-negative bacteria as well as Candida species using the broth microdilution method. The compounds exhibited measurable antimicrobial effects with MIC values ranging from 156 to 625 µg/mL, showing moderate growth inhibition against the tested microorganisms. Although the observed activity was lower than that of the reference antimicrobial agents, the results indicate that these triazole–hydrazone derivatives possess a detectable level of antimicrobial activity and provide a basis for further structural optimization. Collectively, the results suggest that compound 3b represents the most promising lead structure due to its balanced combination of potency, selectivity, and predicted target engagement. Molecular docking was performed to evaluate the binding potential of newly synthesized triazole derivatives (3a–3d) against PI3Kα. The docking protocol was validated by re-docking alpelisib, yielding an RMSD of 0.64 Å. Among the tested compounds, 3b showed the most favorable binding energy (−9.94 kcal/mol) and estimated Ki value (52.13 nM), consistent with its superior in vitro activity. Its interactions with key PI3Kα residues, including Val851, Ser854, Met922, and Asp933, support a stable binding mode within the ATP-binding pocket. In silico ADME and toxicity analyses suggested acceptable drug-likeness characteristics, absence of major hepatotoxic, mutagenic, and carcinogenic liabilities, and moderate predicted acute toxicity profiles. These findings suggest that 3b is the most promising derivative for further validation. Full article

The present study aimed to design, synthesize, and evaluate a new series of thieno[3,2-d]pyrimidin-4(3H)-one-based Schiff bases as potential antileishmanial agents against Leishmania major (L. major). A series of twenty thieno[3,2-d]pyrimidine Schiff base derivatives were synthesized and characterized using FTIR, NMR, and HRMS techniques. Their antipromastigote activities were evaluated in vitro against L. major, while cytotoxic effects were assessed on HUVECs to determine selectivity indices. The most active compound was further investigated using molecular docking against several L. major proteins. Among the tested compounds, compound 12, bearing a 2-hydroxy-5-bromophenyl moiety, exhibited the most potent activity against L. major promastigotes with an IC₅₀ value of 13.7 µM, along with a favorable selectivity index (SI = 17.5), outperforming the reference drug miltefosine (IC₅₀ = 31 µM and SI = 0.2). Docking studies demonstrated that compound 12 showed the strongest binding affinity toward phosphodiesterase B1, supported by a docking score of −9.042 kcal/mol and an MM-GBSA value of −67.21 kcal/mol. This study highlights thieno[3,2-d]pyrimidin-4(3H)-one as a promising scaffold in the context of in vitro antileishmanial screening and suggests the role of ortho-phenolic substitution in enhancing activity and selectivity. Compound 12 emerges as a promising lead, warranting further optimization and biological evaluation in future studies. Full article

Background/Objectives: Transition metal complexes of imidazoles exhibit a variety of biological activities. This makes them promising metal-based drugs for use in medicine. The aim of this research is to investigate the complexes of zinc(II) with N-vinyl, N-allyl, and N-propargylimidazoles, represented by the formula [ZnL₂Cl₂], as potential drug candidates. Methods: Structural studies of the obtained complexes were performed using single-crystal X-ray diffraction analysis, IR and NMR spectroscopy. DFT calculations were used to determine structural, electronic and thermochemical parameters of the complexes. QSAR analysis was performed using PASS. The wound-healing and antihypoxic activities were studied in vivo using models of wounds and acute hypoxia of various origins. The antimicrobial activity of the complexes was evaluated against Staphylococcus aureus Wood 46, Escherichia coli M-17, and the yeast fungus Candida albicans 927. The cytotoxic activity was tested using several cell lines, including monkey kidney (Vero) cells, human cervical cancer cells (Hep2C and HeLa), human lung carcinoma (A549), and human embryonal rhabdomyosarcoma (RD). Results: New complexes of N-allylimidazole and N-allyl-2-methylimidazole with ZnCl₂ were synthesized and characterized. All the studied complexes possess diverse biological activities. While the antimicrobial activity was modest, a distinct antifungal activity was observed. The cytotoxicity of the complexes was found to be mainly in relation to Hep2c and RD cell lines. Conclusions: Based on the results of QSAR analysis and experimental findings, the diverse biological activities of the compounds indicate that they are promising lead structures for further optimization in drug development. Full article

Poly(trimethylene ether) glycol (PO3G), a bio-based polyether polyol with excellent flexibility and superior hydrolytic stability, has emerged as a critical raw material for the preparation of high-performance polymer materials. This work optimized the sulfuric acid-catalyzed polymerization process and assessed the feasibility of using p-toluenesulfonic acid (PTSA) as an alternative catalyst. A parametric study was conducted to establish a reliable operating window for the sulfuric acid system. DFT calculations demonstrated that the driving force for chain growth decreases with increasing chain length, that recombination between chains of significantly different lengths is more favorable than between chains of equal length, and that the formation of disulfate esters is thermodynamically more favorable. Although PTSA required a higher catalyst loading, the resulting polymer had a markedly lower yellowness index. Prolonged reaction times lead to a molecular weight plateau, especially at high PTSA concentrations, while the yellowness index continues to increase after reaching the plateau. ¹H NMR analysis indicated the formation of benzenesulfonate monoester intermediates during PTSA catalysis, suggesting a potentially milder pathway and possibly fewer side reactions compared to the sulfuric acid system. This paper provides theoretical and experimental foundations for the green, efficient synthesis of PO3G and the catalyst optimization for analogous bio-based polyether polyols. Full article

(1) Background: Cinnamaldehyde exhibits a broad spectrum of biological activities, and its α,β-unsaturated aldehyde scaffold serves as a versatile platform for the design of hydrazone derivatives with improved pharmacological properties. (2) Methods: In this study, eight cinnamaldehyde-based hydrazones were synthesized via a one-step condensation reaction between cinnamaldehyde and para-substituted acylhydrazides. Prior to synthesis, an in silico assessment of physicochemical, pharmacokinetic, ADME (absorption, distribution, metabolism, elimination), lead-likeness, and drug-likeness properties was conducted using SwissADME, ACD/Labs v. 9.10, and MDL QSAR v2.2.0.0.446 software. Structural characterization by IR, ¹H NMR, ¹³C NMR, and HR ESI–MS confirmed successful formation of the hydrazone linkage. Cytotoxic activity was evaluated using the MTT assay against selected cancer cell lines. (3) Results: All compounds exhibited favorable lead-like characteristics, including suitable molecular weight, moderate lipophilicity, and acceptable predicted ADME profiles. Biological evaluation revealed moderate, structure-dependent antiproliferative activity with clear cell line selectivity. Among the series, compound CA8 showed the most promising profile, displaying the highest cytotoxic activity against T-cell leukemia KE-37 cells (IC₅₀ = 20.3 ± 2.8 μM), comparable to reference drug melphalan (IC₅₀ = 21.40 ± 3.9 μM), and the highest selectivity index (≥19.7). Structure–activity analysis suggests that an amino substituent enhances both potency and selectivity. (4) Conclusions: Overall, these findings identify cinnamaldehyde hydrazones as a promising scaffold for anticancer drug development and provide a strong basis for further structural optimization. Full article

In response to recent advances in computer-aided drug discovery (CADD) enabled by high-performance computing, computational approaches were employed to support and rationalize the investigation of a VEGFR-2-targeted anticancer candidate, combining molecular-level modeling with experimental validation. Initial in silico ADMET profiling and molecular docking were conducted to support the evaluation of drug-like properties and target engagement within a series of para-toluidine-based derivatives (1–14). The most biologically active compound was further evaluated through 100 ns molecular dynamics simulations and comprehensive DFT calculations to investigate binding stability and electronic characteristics. Based on a rational design strategy and supported by computational analyses, the compounds were synthesized and fully characterized using IR, MS, ¹H/¹³C NMR, and elemental analysis. Biological evaluation was performed against HepG-2, MCF-7, HCT-116, and normal WI-38 cells. Mechanistic studies included VEGFR-2 inhibition, wound-healing migration assays, cell-cycle distribution analysis, apoptosis assessment, and caspase-3 activation. Several derivatives exhibited micromolar cytotoxic activity, with compound 14 emerging as the most active against HepG-2 cells (IC₅₀ = 7.84 ± 0.5 µM), showing cytotoxic activity comparable to that of sorafenib (IC₅₀ = 9.18 ± 0.6 µM) and demonstrating favorable selectivity toward normal WI-38 cells (IC₅₀ = 67.75 ± 3.6 µM). Compound 14 showed moderate VEGFR-2 inhibitory activity (IC₅₀ = 0.55 µM), significant suppression of cell migration, pronounced G₀/G₁ cell-cycle arrest, and robust apoptosis induction supported by caspase-3 activation. Molecular docking and MD simulations supported a stable binding mode within the VEGFR-2 active site. This integrated framework highlights compound 14 as a selectively active VEGFR-2-oriented anticancer candidate scaffold with a favorable selectivity profile, supported by experimental and computational analyses, warranting further lead optimization. Full article

Bacterial and fungal infections, together with oxidative stress-mediated damage, remain major challenges in human health and in the protection of materials, highlighting the need for new multifunctional molecules that combine antioxidant and antimicrobial properties. In this context, a new chloropyridine-based derivative, N4,N4-bis((6-chloropyridin-3-yl)methyl)-N1,N1-diethylpentane-1,4-diamine (AMZ), was synthesized via a simple, catalyst-free N-alkylation of N1,N1-diethylpentane-1,4-diamine with 2-chloro-4-(chloromethyl)pyridine in acetonitrile at 55 °C, affording a 62% yield. The structure of AMZ was confirmed by melting point determination, ¹H and ¹³C NMR spectroscopy, and EI–MS analysis. Its antioxidant activity was evaluated using DPPH and FRAP assays with BHT as a reference standard, while antibacterial and antifungal activities were assessed via disk diffusion and microdilution methods to determine inhibition zones and MIC/MBC values. In silico investigations included drug-likeness and ADMET predictions, as well as molecular docking on catalase (PDB: 2CAG) and fungal CYP51 (PDB: 1EA1). AMZ exhibited dose-dependent radical scavenging in the DPPH assay, reaching 76.88 ± 3.20% inhibition at 1000 µg/mL, with an EC₅₀ of 26.03 ± 0.21 µg/mL, close to that of BHT (23.65 ± 0.22 µg/mL). In the FRAP assay, AMZ showed a higher reducing power than BHT at a low concentration (OD₅₀ µg/mL 0.177 ± 0.023 vs. 0.134 ± 0.017), although its FRAP EC₅₀ was higher (700.48 ± 22.54 vs. 400.16 ± 8.67 µg/mL). AMZ displayed broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi, with particularly strong effects on Bacillus subtilis (44.5 ± 0.5 mm; MIC/MBC 0.008 mg/mL) and Aspergillus niger (30 mm; MIC/MBC 0.030 mg/mL), in some cases comparable or superior to streptomycin and fluconazole. In silico analysis indicated that AMZ fulfilled major drug-likeness rules, showed high predicted intestinal absorption (91.14%), and was classified as non-AMES toxic, while docking predicted favorable binding to catalase and CYP51, in agreement with the experimental antioxidant and antifungal activities. These findings highlight the potential of AMZ as a multi-target pyridine-based lead compound that warrants further structural optimization and in vivo evaluation for applications in oxidative-stress-related and infectious conditions. Full article

Linear alkylbenzene (LAB) is the main raw material used to make biodegradable detergents, and its production process is based on aromatic alkylation. HY zeolites that have undergone controlled dealumination and desilication have led industrial standards amongst solid acid catalysts because of their controllable acidity and hierarchical pore structure. Coke formation in such systems can assume a dual role, which is dependent on its condition. Though the over-deposition is known to cause deactivation by blocking the micropores, Bronsted acid-site masking, and diffusion collapse, the low-level deposition could also be done to increase the monoalkylate selectivity by the pore mouth catalysis, steric modulation, and selective suppression of secondary alkylation pathways. The critical review is done on the structural-kinetic interaction that determines the coke evolution in HY-based catalysts. In order to moderate the acid-site density and enhance hydrothermal stability, dealumination (Si/Al optimization of about 2.5 to 30–100) occurs, but to reduce deep-pore coke formation, desilication (interconnected mesopores) is created. The bimodal porosity and regulated acidity are found to be synergistic, as hierarchical HY zeolites produced through successive cycles of steam and alkaline treatments not only show LAB selectivity in excess of 90% but also exhibit much longer catalyst lifetimes. Quantitative research on the beneficial coke regime revealed that it was composed of about 36 wt% hydrogen-rich species, which were localized at the pore mouths, hence enhancing monoalkylation selectivity by 15–40%. Beyond a critical transition window (e.g., 8–12 wt.%), coke formation to condensed polyaromatic and graphitic products leads to fast deactivated coke formation, which is due to percolation limits and transport-controlled kinetics. More advanced techniques of characterization of the coke, e.g., temperature-programmed oxidation (TPO), ²⁷Al MAAS NMR, and UV-Raman spectroscopy, indicate how the coke is changed to highly structured graphitic deposits of high oxidation activation energy. Activity recovery of 85–98% is obtained in regeneration processes, including controlled oxidative calcination, microwave-based and plasma-based processes, and thermal management protocols, and it would be determined by the chemistry of the coke, its spatial distribution, and the regeneration protocols. This paper has developed a mechanistic coke control system by cross-tuning the acidity and development of an effective pore network, which led to a sustainable aromatic alkylation reaction with minimal activity loss, high selectivity, and long life. Full article

Fragment-based drug discovery (FBDD) has emerged as a primary approach for identifying low molecular weight leads that can be systematically optimized into high-affinity compounds. Because fragments bind inherently weakly, their detection relies on highly sensitive biophysical tools. Nuclear magnetic resonance (NMR) spectroscopy is uniquely qualified for fragment screening due to its capability in detecting weak interactions across a broad affinity range while providing site-specific binding information that supports structure-guided optimization. While FBDD is a mature field for protein targets, structured and disease-relevant RNAs have transitioned from ‘undruggable’ molecules to viable therapeutic targets for small-molecule intervention. Recent studies demonstrate that NMR-based screening can identify authentic RNA binders and guide their evolution into potent, selective ligands. This review summarizes the practical and methodological pipelines for RNA-targeted small molecule NMR screening, covering RNA construct design, sample preparation, and library pooling strategies. We evaluate both ligand- and RNA-observed NMR assays for primary hit screening and validation, integration of NMR restraints with structural modeling, and representative case studies. Finally, we discuss current bottlenecks in the field and highlight emerging strategies to accelerate the discovery of RNA-directed therapeutics. Full article

Background/Objectives: Cancer remains one of the most significant challenges in modern medicine, requiring the continuous development of novel molecular scaffolds with anticancer potential that act through multiple pathways. Heterocyclic compounds incorporating indole, triazole, oxadiazole, and thiadiazine motifs have attracted considerable attention due to their diverse pharmacological activities. This study aimed to design, synthesize, and evaluate new hybrid heterocyclic systems, including 1,2,4-triazole, 1,3,4-oxadiazole, and thiadiazine motifs, targeting liver and breast cancer. Methods: A series of indolyl-based heterocyclic compounds was synthesized using efficient and environmentally friendly protocols. Indolyl-triazol-thiadiazin-6-ol 5 was prepared via solvent-free fusion of esters 2 and 3 or the corresponding acid 4. Oxadiazole derivatives were produced by reacting hydrazide intermediates with carbon disulfide. Triazole derivatives were synthesized via cylization of thiosemicarbazide 9 in aqueous KOH (4.0 N). Structural characterization was performed using Fourier Transform InfraRed (FTIR), ¹H and ¹³C NMR spectroscopy, and electron impact mass spectrometry (EIMS). Cytotoxic activity was evaluated against liver and breast cancer cell lines, and VEGFR-2 kinase inhibition was assessed for selected derivatives. Results: The synthesized compounds demonstrated notable cytotoxicity activity, with compounds 4, 5, and 9 exhibiting IC₅₀ values in the low micromolar range. Enzymatic assays revealed that compounds 4 and 9 showed strong VEGFR-2 inhibition (97.9% and 96.4%, respectively), indicating apoptosis-inducing effects. Conclusions: The synthesized indolyl-based hybrid heterocycles represent a promising chemotype with in vitro cytotoxic activity and VEGFR-2 inhibitory effects, supporting further investigation, optimization, and mechanistic studies to evaluate their potential lead for anticancer drug development. Full article

Bromodomain-containing protein 9 (BRD9) belongs to the non-canonical BAF chromatin remodeling complex and represents a relevant therapeutic target in pathologies featuring dysregulated epigenetic control. The absence of clinically validated inhibitors and the need for diversified chemical entities highlight the interest in identifying new scaffolds targeting this protein. In this study, Saturation Transfer Difference Nuclear Magnetic Resonance (STD NMR) was employed to assess its suitability for characterizing BRD9–ligand interactions within a fragment-based discovery framework. STD NMR conditions were first optimized using the known BRD9 ligand 1, verifying the presence of interaction signals. A pharmacophore-based virtual screening campaign was then performed using libraries of commercially available fragments, leading to the selection of a novel isatin derivative, i.e., compound 2, whose binding was demonstrated in AlphaScreen assays. STD NMR experiments provided epitope mapping consistent with the predicted binding mode, thus supporting the stability of the interaction in solution. Moreover, a competitive STD experiment demonstrated displacement of 2 by a reference ligand, confirming the binding within the canonical BRD9 pocket. Overall, this study establishes STD NMR as a reliable approach for probing BRD9–ligand interactions and for the identification and validation of BRD9-targeting scaffolds suitable for future structure-guided optimization. Full article