Search Results (132)

Dermatophytes are highly infectious pathogenic fungi that colonize keratinized tissues like skin, hair, and nails, causing superficial infections such as tinea capitis, onychomycosis, tinea corporis, and tinea pedis in humans and animals. In immunocompromised patients, they may invade deeper tissues and organs, leading to severe or life-threatening conditions if untreated or inadequately managed. While most infections respond to topical antifungals, some require complex treatment and show resistance to standard therapies. Therefore, novel antifungal agents are needed. We investigated the antidermatophytic activity of imidazole-thiosemicarbazides against Microsporum canis, Trichophyton spp., and Chrysosporium spp. using the broth microdilution method, comparing results to ketoconazole and amphotericin B through minimal inhibitory concentration (MIC), half-maximal inhibitory concentration (IC₅₀), and selectivity index (SI). Iodine- and bromine-substituted compounds showed the strongest activity, with MICs of 15.15 (IC₅₀ < 1 μM; SI > 213) and 73.46 μg/mL (IC₅₀ < 1 μM; SI > 846) against T. tonsurans, and 3.87 (IC₅₀ = 7.21 μM; SI > 29.6) and 7.38 μg/mL (IC₅₀ = 11.06 μM; SI = 76.6) against M. canis. In silico analysis revealed interactions with α-keratin and lanosterol-14-α demethylase (the azole target enzyme), suggesting enhanced drug retention and action. These findings support these compounds as promising leads for further antifungal development. Full article

Recent studies on brominated tyrosine-derived marine natural products have significantly expanded the library of known structures and revealed their potent and diverse antitumor mechanisms. Building upon our previous research on the natural product itampolin A isolated from marine sponges, we conducted structural optimizations and explored the structure–-activity relationships (SARs) of novel scaffold derivatives concerning their inhibitory activities against lung cancer cells. In the present study, we further synthesized 15 novel derivatives, and compound 4l demonstrated selective anti-proliferative activity against gefitinib-resistant PC9/GR cells, showing 4-fold greater potency compared to parental PC9 cells. Building on this finding, the present study aims to investigate the molecular mechanisms underlying the anti-proliferative effects of 4l in drug-resistant NSCLC models. Through cell cycle analysis, apoptosis assays, and signaling pathway evaluation, we seek to establish a theoretical foundation for developing novel therapeutic agents against chemotherapy-resistant lung cancer. Full article

Three new series of indolizines (5a–f, 6a–f and 7a–g), functionalized with bromine or ethyl ester substituents on the pyridine ring, were designed and synthesized as promising anticancer agents. The synthesis of indolizine derivatives was carried out using the 1,3-dipolar cycloaddition of pyridinium N-ylides to ethyl propiolate as a key step. Spectral characterization (using NMR, FT-IR, HRMS and X-ray diffraction) showed that two types of cycloadducts 5a–f and 6a–f were obtained when the ylides generated by the 3-bromopyridinium salts were used as 1,3-dipoles in Huisgen cycloaddition reactions to ethyl propiolate. The anticancer effect of selected compounds was in vitro assessed against the National Cancer Institute (NCI) panel of 60 human tumor cells, at 10 μM concentration, with three compounds (5c, 6c and 7g) showing promising inhibitory activity on the growth of several cell lines including lung, brain, renal cancer and melanoma, as well as a cytotoxic effect against HOP-62 non-small cell lung cells (34% for compound 5c and 15% for compound 7g) and SNB-75 glioblastoma cells (15% for compound 5c and 14% for derivative 7c). Molecular docking revealed favorable binding affinities for 5c, 6c and 7g (–9.22 to –9.88 kcal/mol) at the colchicine-binding site of tubulin with key interactions involving βASN-258, βALA-317, and βLYS-352 residues for 5c, βASN-258 in case of 6c, and αVAL-181 and βLYS-254 for derivative 7g. According to the in silico ADMET analysis, the active compounds are predicted to exhibit good oral bioavailability, promising drug-like qualities and low toxicity risks. Full article

The efficient synthetic routes and evaluates cytotoxic profiles of denitroaristolochic acids II–V (DAA-II–V) were demonstrated in this study. Based on retrosynthetic analysis, a modular synthetic strategy was developed through Suzuki–Miyaura coupling, Wittig reaction, and bismuth triflate-catalyzed intramolecular Friedel–Crafts cyclization to efficiently construct the phenanthrene core. Process optimization significantly improved yields: aryl bromide intermediate A reached 50.8% yield via bromination refinement, while arylboronic ester intermediate B overcame selectivity limitations. Combining Darzens condensation with Wittig reaction enhanced throughput, achieving 88.4% yield in the key cyclization. Structures were confirmed by NMR and mass spectra. CCK-8 cytotoxicity assays in human renal proximal tubular epithelial cells revealed distinct toxicological profiles: DAA-III and DAA-IV exhibited IC₅₀ values of 371 μM and 515 μM, respectively, significantly higher than the nitro-containing prototype AA-I (270 μM), indicating that the absence of nitro group attenuates but does not eliminate toxicity, potentially via altered metabolic activation. DAA-II and DAA-V showed no detectable cytotoxicity within assay limits, suggesting reduced toxicological impact. Structure–activity analysis exhibited that the nitro group is not essential for cytotoxicity, with methoxy substituents exerting limited influence on potency. This challenges the conventional DNA adduct-dependent toxicity paradigm, implying alternative mechanisms like oxidative stress or mitochondrial dysfunction may mediate damage in denitro derivatives. These systematic findings provide new perspectives for AA analog research and a foundation for the rational use and safety assessment of Aristolochiaceae plants. Full article

The pyrrolo[2,3-d]pyrimidine (7-deazapurine) scaffold is a unique heterocyclic system included in the composition of most nucleotides. In this study, series of the pyrrolo[2,3-d]pyrimidine-imines and 3-halo-substituted pyrrolo[2,3-d]pyrimidines were designed and prepared in high yields. Condensed pyrimidines are obtained via carbonyl-amine condensation and carbon-halogen bond formation. Pyrrolo[2,3-d]pyrimidine-imines containing a bromine substituent at position C-4 of the phenyl ring and azepine side-ring exhibited superior antitumor activity on the colon cancer HT-29 cell line; IC₅₀ values were 4.55 and 4.01 µM, respectively. These results revealed an interesting pattern, where condensed pyrimidinones containing an azepine ring demonstrated selective antitumor activity on the colon cancer cell line HT-29. In addition, the molecular docking results suggest that compound 8g provided a thorough understanding of its interactions with the DDR2 active site. This could pave the way for further development and optimization of DDR-targeting drugs, contributing to advancements in cancer therapeutics. This lead compound may serve as design templates for further studies. Full article

Skin aging is mainly caused by external factors like sunlight, which triggers oxidative stress and chronic inflammation. Natural halogenated flavonoids have demonstrated anti-inflammatory properties. Inspired by the macroalgae-derived bromophenol BDDE, we investigated the anti-inflammatory potential of structure-related chalcones (1–7). Chalcones 1 and 7 showed the least cytotoxicity in keratinocyte and macrophage cells. Chalcones 1, 2, 4, and 5 exhibited the most significant anti-inflammatory effects in murine macrophages after lipopolysaccharide stimulation, with chalcone 1 having the lowest IC₅₀ value (≈0.58 μM). A SNAP assay confirmed that chalcones do not exert their effects through direct NO scavenging. Symmetrical bromine atoms and 3,4-dimethoxy groups on both aromatic rings improved the anti-inflammatory activity, indicating a relevant structure–activity relationship. Chalcones 1 and 2 were selected for study to clarify their mechanisms of action. At a concentration of 7.5 μM, chalcone 2 demonstrated a rapid and effective inhibitory action on the protein levels of inducible nitric oxide synthase (iNOS), while chalcone 1 exhibited a gradual inhibitory action. Moreover, chalcone 1 effectively activated the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway with around a 3.5-fold increase at the end of 24 h at 7.5 μM, highlighting its potential as a modulator of oxidative stress responses. These findings place chalcone 1 as a promising candidate for skincare products targeting inflammation and skin aging. Full article

Background/Objectives: Diabetes mellitus is a group of chronic metabolic disorders characterized by persistent hyperglycemia. Aldose reductase, the first enzyme in the polyol pathway, plays a key role in the onset of long-term diabetic complications. Aldose reductase inhibition has been widely established as a potential pharmacotherapeutic approach to prevent and treat diabetes mellitus-related comorbidities. Although several promising aldose reductase inhibitors have been developed over the past few decades, they have failed in clinical trials due to unacceptable pharmacokinetic properties and severe side effects. This paper describes the design, synthesis, and pharmacological evaluation of four novel 5-halogenated N-indolylsulfonyl-2-fluorophenol derivatives (3a-d) as aldose reductase inhibitors. Methods: The design of compounds was based on a previously published lead compound (IIc) developed by our research group to enhance its inhibitory capacity. Compounds 3a-d were screened for their ability to inhibit in vitro partially purified aldose reductase from rat lenses, and their binding modes were investigated through molecular docking. Results: The presence of a sulfonyl linker between indole and o-fluorophenol aromatic rings is mandatory for potent aldose reductase inhibition. The 5-substitution of the indole core with halogens resulted in a slight decrease in the inhibitory power of 3a-c compared to IIc. Among halogens, bromine was the most capable of filling the selectivity pocket through hydrophobic interactions with Thr113 and Phe115 residues. Conclusions: Although our strategy to optimize the inhibitory potency of IIc via inserting halogen atoms in the indole scaffold was not fruitful, aromatic ring halogenation can be still utilized as a promising approach for designing more potent aldose reductase inhibitors. Full article

The novel benzanthrone derivative, 2-bromo-3-aminobenzo[de]anthracene-7-one (2-Br-3-NH₂BA), was synthesized and extensively characterized to investigate its photophysical behavior in various solvents. It was prepared through selective bromination of 3-aminobenzanthrone using N-bromosuccinimide in dimethylformamide at −20 °C. Featuring a donor–π–acceptor (D–π–A) structure, 2-Br-3-NH₂BA exhibits pronounced solvatochromism due to the intramolecular charge transfer (ICT) between the amino donor and the carbonyl acceptor groups. Optical measurements conducted in eight solvents of varying polarity revealed a significant bathochromic shift in both absorption and fluorescence emission, with emission maxima red-shifting by over 110 nm from non-polar to polar environments. Corresponding reductions in the optical band gap energies, as calculated from Tauc plots, further support solvent-induced electronic state modulation. Additionally, quantum yield analysis showed higher fluorescence efficiency in non-polar solvents, while polar solvents induced twisted intramolecular charge transfer (TICT), leading to emission quenching. These findings demonstrate the sensitivity of 2-Br-3-NH₂BA to environmental polarity, making it a promising candidate for color-tunable luminescent applications in optoelectronics and sensing. However, further studies in the solid state are required to validate its applicability in device architectures such as OLEDs. Full article

Marine biofouling is a significant challenge for industries that rely on seawater. This study examined the effect of structural materials, carbon concentration, and salinity on biofilm formation. Furthermore, it compares the disinfection efficiency of chlorine (NaClO) and bromine (NaBr) biocides and attempts to identify their optimal dosing. Among tested materials, PVC exhibited the highest microbial attachment (40%), followed by plastic (30%) and concrete (23%). Biofilm attachment and growth increased with higher concentrations of total organic carbon (TOC), which depends upon the seawater’s salinity. The simultaneous reduction of salinity and TOC concentration further enhanced the biofilm attachment and growth. A strong positive linear correlation (r = 0.98 and p = 0.003) was found between the initial cell count of seawater and biofilm formation. Disinfection experiments showed that NaBr (97.36%) was slightly more effective than NaClO (95.83%). Response Surface Methodology (RSM) identified optimal disinfection conditions: 0.6 mg/L biocide concentration and 138 min dosing period. Generally, there are three strategies for reducing biofilm growth: selecting appropriate materials, controlling carbon concentrations, or optimizing concentrations and dosing periods with biocides. Full article

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers worldwide due to its resistance to conventional therapies that is attributed to its dense and acidic tumor microenvironment. Chemotherapy based on gemcitabine usually lacks efficacy due to poor drug penetration and the metabolic characteristics of the cells adapted to grow at a more acidic pH_e, thus presenting a more aggressive phenotype. In this context, photodynamic therapy (PDT) offers a promising alternative since it generally does not suffer from the same patterns of cross-resistance observed with chemotherapy drugs. In the present work, a novel bromine-substituted heptamethine-cyanine dye (BrCY7) was synthesized, loaded into PEG-PLGA NPs, and tested on the pancreatic ductal adenocarcinoma cell line cultured under physiological (PANC-1 CT) and acidic (PANC-1 pH selected) conditions, which promotes the selection of a more aggressive phenotype. The cytotoxicity of BrCY7-PEG-PLGA is dose-dependent, with an IC₅₀ of 2.15 µM in PANC-1 CT and 2.87 µM in PANC-1 pH selected. Notably, BrCY7-PEG-PLGA demonstrated a phototoxic effect against PANC-1 pH selected cells but not on PANC-1 CT, which makes these findings particularly relevant since PANC-1 pH selected cells are more resistant to gemcitabine as compared with PANC-1 CT cells. Full article

Fascaplysins form a group of marine natural products with unique cationic five-ring coplanar backbone. Native fascaplysin exhibits a broad spectrum of bioactivities, among which the cytotoxic activity has been the most investigated. Several fascaplysin derivatives have more selective biological effects and are promising as lead compounds. Thus, the introduction of a substituent at C-9 of fascaplysin leads to a strong increase in its antimicrobial properties. Here, a comparative assessment of the antimicrobial activity of synthetic analogs of the marine alkaloids 3-bromofascaplysin, 10-bromofascaplysin, and 3,10-dibromofascaplysin, along with some of their isomers and analogs, was carried out against a panel of Gram-positive bacteria in vitro. For the first time, a significant increase in the antimicrobial activity of fascaplysin was observed when a substituent was introduced at C-3. The introduction of two bromine atoms at C-2 and C-9 enhances the antimicrobial properties by 4 to 16 times, depending on the tested strain. Evaluation of the antimicrobial potential in vivo showed that fascaplysin and 3,10-dibromofascaplysin had comparable efficacy in the mouse staphylococcal sepsis model. Additionally, 3,10-dibromofascaplysin demonstrated a strong and reliable antitumor effect in vivo on the Ehrlich carcinoma inoculated subcutaneously, with a value of tumor growth inhibition by 49.2% 20 days after treatment. However, further studies on alternative chemical modifications of fascaplysin are needed to improve its chemotherapeutic properties. Full article

Electrodialysis (ED) has already been applied to recover nickel in galvanizing processes, allowing nickel recovery and the production of a treated effluent with demineralized water quality. However, the growth in ED use is still limited by the production and commercialization of ion-selective membranes, currently limited to a few large companies. Therefore, this paper presents the development of homogeneous cationic and anionic membranes made from poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) for ED use. Cationic membranes were prepared by the sulfonation reaction of PPO under different experimental conditions (PPO:H₂SO₄ molar ratio and reaction time). Anionic membranes were prepared by the bromination reaction of PPO, followed by the amination reaction. The membranes were characterized for their chemical and electrochemical properties, including ion exchange capacity, conductivity, thermal stability, and surface morphology. The optimal conditions for cationic membrane sulfonation were achieved with a 1:4.4 PPO:H₂SO₄ molar ratio, and a reaction time of 0.5 h. For anionic membranes, the best results were obtained with bromination, with a PPO:NBS (N-Bromosuccinimide) molar ratio of 1:0.5, followed by 14 days of amination. Overall, 91.8% chloride, 90.9% sulfate, and 85.5% nickel ion extraction was achieved, highlighting PPO as a promising polymer for the development of anionic and cationic ion-selective membranes for ED. Full article

This study explores Zeolitic Imidazolate Frameworks (ZIFs) as promising materials for adsorbing alcohol vapors, one of the main contributors to air quality deterioration and adverse health effects. Indeed, this sub-class of Metal–Organic Frameworks (MOFs) offers a promising alternative to conventional adsorbents like zeolites and activated carbons for air purification. Specifically, this investigation focuses on ZIF-8_Br, a brominated version of ZIF-8_CH₃, to evaluate its ability to capture aliphatic alcohols at lower partial pressures. The adsorption properties have been investigated using both experimental and computational methods combining Density Functional Theory and Grand Canonical Monte Carlo simulations. The Ideal Adsorbed Solution Theory (IAST) has been used to assess the material selectivity in the presence of binary equimolar alcohol mixtures. Compared to ZIF-8_CH₃, the brominated analog has been shown to feature a higher affinity for alcohols, a property that could be advantageously exploited in environmental remediation or in the development of membranes for alcohol vapor sensors. Full article

Photoredox-catalyzed phosphonylation of bromo-substituted 1,10-phenanthrolines under visible light irradiation was studied. The reaction was shown to proceed under mild conditions with Eosin Y as a photocatalyst in DMSO under blue light irradiation. It is transition-metal-free and affords the target phosphonate-substituted 1,10-phenanthrolines in moderate yields (26–51%) in 22 to 40 h. The rate and selectivity of the reaction depend largely on the position of the bromine atom, as well as on the nature and position of other substituents in the 1,10-phenanthroline core. Full article

Leishmaniasis, a protozoan disease affecting humans, exposes significant shortcomings in current treatments. In continuation to our previous findings on amidoxime-based antileishmanial compounds bearing a 4,5-dihydrofuran scaffold, twelve new amidoxime derivatives substituted at position 3 with an amide bearing a nitrogen heterocycle were synthesized. This series was designed to replace the sulfone and aryl group on a previously reported HIT. The synthesis of these compounds involved the following three-step pathway: manganese (III) acetate-based cyclization of a β-ketoester, followed by amidation with LiHMDS and a final reaction with hydroxylamine. Three of them, containing either bromine, chlorine, or methyl substitutions and featuring a pyridine moiety, showed an interesting toxicity–activity relationship in vitro. They exhibited IC₅₀ values of 15.0 µM, 16.0 µM, and 17.0 µM against the promastigote form of the parasite and IC₅₀ values of 0.5 µM, 0.6 µM, and 0.3 µM against the intracellular amastigote form, respectively. A selectivity index (SI) greater than 300 was established between the cytotoxic concentrations (in murine macrophages) and the effective concentrations (against the intracellular form of Leishmania amazonensis). This SI is at least seventy times higher than that observed for Pentamidine and twenty-five times higher than that observed for the reference HIT, as previously reported. Full article