Search Results (577)

One of the promising research areas involving carborane derivatives is boron neutron capture therapy (BNCT). Due to the high boron atom content in carborane molecules, these compounds are considered potential candidates for BNCT-based cancer treatment. Despite ongoing studies on various biologically active carboranyl-containing compounds, the search continues for substances that meet the stringent requirements of effective BNCT agents. In this study, the synthesis of carboranyl-containing derivatives of β-arylaliphatic acids is described, along with the investigation of their reactivity with primary and secondary amines, as well as with metals and their hydroxides. The molecular structures of the synthesized compounds were confirmed using Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, elemental analysis, and mass spectrometry (LC-MS). Cytotoxicity of the water-soluble compound potassium 3-(2-isopropyl-1,2-dicarba-closo-dodecaboran-1-yl)-3-phenylpropanoate was evaluated using several cell lines, including HdFn and MCF-7. Full article

Diclofenac, an aryl-acetic acid derivative from the non-steroidal anti-inflammatory drug class, is the subject of multiple non-clinical and clinical studies regarding its usefulness in treating some dermatologic pathologies with an inflammatory, auto-immune, or proliferative component. Diclofenac is now approved for the topical treatment of actinic keratoses (AK), pre-malignant entities that have the risk of transformation into skin carcinomas. The hypothesis that diclofenac increases granular layer development in the mice tail model, having an anti-psoriatic effect, was demonstrated in a previous study in which 1% and 2% diclofenac ointment was evaluated. The aim of the present study was to perform experimental research on the topical effect of diclofenac in the mice tail model, by testing 4% and 8% diclofenac ointment, which is presented in the first part of the manuscript. In the second part of the manuscript, we also aimed to conduct a literature review regarding topical diclofenac uses in specific dermatological entities by evaluating the articles published in PubMed and Scopus databases during 2014–2025. The studies regarding the efficacy of topical diclofenac in dermatological diseases such as AK and field cancerization, actinic cheilitis, basal cell carcinoma, Bowen disease, Darier disease, seborrheic keratoses, and porokeratosis, were analyzed. The results of the experimental work showed a significant effect of 4% and 8% diclofenac ointment on orthokeratosis degree when compared to the negative control groups. Diclofenac in the concentration of 4% and 8% significantly increased the orthokeratosis degree compared to the negative control with untreated mice (p = 0.006 and p = 0.011, respectively, using the Kruskal–Wallis test) and to the negative control with vehicle (p = 0.006 and p = 0.011, respectively, using the Kruskal–Wallis test). The mean epidermal thickness was increased for the diclofenac groups, but not significantly when compared to the control groups. The results are concordant with our previous experiment, emphasizing the need for future clinical trials on the use of topical diclofenac in psoriasis. Full article

In this work, we described the synthesis of 4-(methoxycarbonyl)phenyl 5-bromofuran-2-carboxylate by reacting 5-bromofuroic acid with methylparaben in the incorporation of DCC/DMAP (Steglich esterification) as coupling agents. Later on, we subsequently synthesized a series of 4-(methoxycarbonyl)phenyl 5-aryl furan-2-carboxylates (5a–5e) through Suzuki coupling catalyzed by palladium (0) between 4-(methoxycarbonyl)phenyl 5-bromofuran-2-carboxylate (3) with several substituted arylated and heteroaryl boronic acids (4). DFT calculations were computed to elucidate electronic structural features of synthesized molecules (5a–5e) and to validate these findings by correlating with theoretical and experimental spectroscopic analysis. Furthermore, geometrical optimization, thermodynamic features, as FMO orbitals, MESP maps, NLO behavior and reactivity descriptors, were also determined from the PBE0 D3BJ/def2-TZVP/SMD_1,4-dioxane theory level to confirm the structural features of synthesized molecules. Full article

Kynurenic acid (KYNA), a tryptophan metabolite, possesses immunomodulatory properties, although the molecular mechanism of this action has not yet been resolved. In the present study, the effects of KYNA on the secretion of selected cytokines and chemokines by macrophages derived from the human THP-1 cell line are investigated. Furthermore, the involvement of the aryl hydrocarbon receptor (AhR) and the G protein-coupled receptor 35 (GPR35) in mediating the effects of KYNA was examined. In lipopolysaccharide (LPS)-stimulated THP-1-derived macrophages, KYNA significantly reduced IL-6 and CCL-2, but increased IL-10 and M-CSF levels. AhR antagonist CH-223191 reduced the KYNA influence on IL-6, CCL-2, and M-CSF production, while the GPR35 antagonist, ML-145, blocked KYNA-induced IL-10 production. Furthermore, it was shown that THP-1 derived macrophages were capable of synthesizing and releasing KYNA and that its production was increased in the presence of LPS. These findings suggest that THP-1-derived macrophages are a source of KYNA and that KYNA modulates inflammatory responses predominantly through AhR and GPR35 receptors. Our study provides further evidence for the involvement of macrophages in immunomodulatory processes that are dependent on AhR and GPR35 receptors, as well as the potential role of KYNA in these phenomena. Full article

In the field of green chemistry, the development of more sustainable and cost-efficient methods for synthesizing primary amines is of paramount importance, with catalyst research being central to this effort. This work presents a facile, aqueous-phase synthesis of highly active cobalt catalysts (Co-Ph@SiO₂(x)) via pyrolysis of silica-supported cobalt–phenanthroline complexes. The optimized Co-Ph@SiO₂(900) catalyst achieved exceptional performance (>99% conversion, >98% selectivity) in the reductive amination of acetophenone to 1-phenylethanamine using NH₃/H₂. Systematic studies revealed that its exceptional performance originates from the in situ pyrolysis of the cobalt–phyllosilicate complex. This process promotes the uniform distribution of metal cobalt nanoparticles, simultaneously enhancing porosity and imparting bifunctional (acidic and basic) properties to the catalyst, resulting in outstanding catalytic activity and selectivity. The catalyst demonstrated broad applicability, efficiently converting diverse ketones (aryl-alkyl, dialkyl, bioactive) and aldehydes (halogenated, heterocyclic, biomass-derived) into primary amines with high yields (up to 99%) and chemoselectivity (>40 examples). This sustainable, non-noble metal-based catalyst system offers significant potential for industrial primary amine synthesis and provides a versatile tool for developing highly selective and active heterogeneous catalysts. 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

Boronic acids are an important class of molecules diversely used in organic synthesis, catalysis, medicinal chemistry, and for the design of functional materials. Particularly, aryl boronic acids in the solid state are known to exhibit pharmaceutical and photoluminescent properties for antimicrobial, sensing, and drug delivery applications. Furthermore, the phenazine molecule is known for its diverse pharmacological properties, including antibiotic activity. In the case of molecular crystalline solids, it is well established that understanding noncovalent interactions remains key to designing or engineering their functional properties. While both aryl boronic acids and phenazine molecules individually represent an important class of compounds, their co-assembly in the crystalline state is of interest within the context of supramolecular chemistry and crystal engineering. Herein, we report the supramolecular features of two newly synthesized cocrystals, which are composed of para-F/CF₃-substituted phenylboronic acids, respectively, and phenazine, as demonstrated by structure analysis by single-crystal X-ray diffraction. Full article

Herein a rapid, metal-free, and highly efficient synthesis of aryl ynamides from aryl alkynyl acids has been described. This approach, utilizing tertiary amines as an amino source via metal-free C-N cleavage, enabled the construction of a diverse range of aryl ynamides with medium to excellent yields (33 examples, up to 95% yield). This reaction exhibits significantly enhanced efficiency compared to the conventional stepwise approach involving aryl alkynyl acids and secondary amines. It can be successfully scaled up, providing a practical and environmentally benign strategy for alkynamide synthesis. Full article

The procedure for the generation of azirinyl-substituted nitrile oxides by the reaction of 2-(diazoacetyl)-2H-azirines with tert-butyl nitrite while preserving the azirine ring has been developed. The [3+2] cycloaddition of azirinyl-substituted nitrile oxides to terminal acetylenes produced azirinyl(isoxazolyl)ketones with various substituents in position 3 of azirine and position 5 of isoxazole fragments in a 51–91% yield at room temperature in DCM. DFT calculations and experimental data are consistent with the assumption that the formation of azirinyl-substituted nitrile oxides is accelerated by the acid catalyst. Cycloadducts of nitrile oxides with aryl/hetarylacetylenes and DMAD can be obtained by catalysis with boron trifluoride etherate, which significantly expands the scope of application of the reaction. Expansion of the azirine ring of the prepared cycloadducts allows obtaining a wide range of structurally diverse functionalized isoxazole-containing heterocyclic hybrids. LED light induces isomerization of the azirinecarbonyl moiety of the azirinyl(isoxazolyl)ketones, resulting in the formation of a set of 3,5’-biisoxazoles in a 40–71% yield, while the catalytic reaction of the azirine moiety with 1,3-diketones opens the way to pyrrole- and isoxazole-containing hybrids. 2-(Isoxazole-3-ylcarbonyl)-3-arylazirines were also easily isomerized to 3-(oxazol-5-yl)isoxazoles in methanol in the presence of excess potassium carbonate at room temperature. Full article

Background/Objectives: Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are highly sensitive clinical imaging modalities, frequently employed in conjunction with magnetic resonance imaging (MRI) or computed tomography (CT) for diagnosing a wide range of disorders. Efficient and robust radiolabeling methods are needed to accommodate the increasing demand for PET and SPECT tracer development. Copper-mediated radiohalogenation (CMRH) reactions enable rapid late-stage preparation of radiolabeled arenes, yet synthetic challenges and radiolabeling precursors’ instability can limit the applications of CMRH approaches. Methods: A series of aryl-boronic acids were converted into their corresponding aryl-boronic acid 1,1,2,2-tetraethylethylene glycol esters [ArB(Epin)s] and aryl-boronic acid 1,1,2,2-tetrapropylethylene glycol esters [ArB(Ppin)s] as stable and versatile precursor building blocks for radiolabeling via CMRH. General protocols for the preparation of ¹⁸F-labeled and ¹²³I-labeled arenes utilizing CMRH of these substrates were developed and applied. The radiochemical conversions (RCC) were determined by radio-(U)HPLC. Results: Both ArB(Epin)s and ArB(Ppin)s-based radiolabeling precursors were prepared in a one-step synthesis with chemical yields of 49–99%. Radiolabeling of the aryl-boronic esters with fluorine-18 or iodine-123 via CMRH furnished the corresponding radiolabeled arenes with RCC of 7–99% and 10–99%, respectively. Notably, a radiohalogenated prosthetic group containing a vinyl sulfone motif was obtained with an activity yield (AY) of 18 ± 3%, and applied towards the preparation of two clinically relevant PET tracers. Conclusions: This approach enables the synthesis of stable radiolabeling precursors and thus provides increased versatility in the application of CMRH, thereby supporting the development of novel PET and SPECT radiotracers. Full article

A series of new isatin hydrazones bearing phosphorus-containing moiety was synthesized through a simple, high-yield and easy work-up reaction of phosphine oxide (Phosenazide) or phosphinate (2-chloroethyl (4-(dimethylamino)phenyl)(2-hydrazinyl-2-oxoethyl)phosphinate, CAPAH) hydrazides with aryl-substituted isatins. The ³¹P NMR technique showed that, in most cases, out of 12 examples in solution, the ratio of the two spatial isomers varied from 1:1 to 1:3. Quantum chemical calculations confirmed the predominance of Z,syn form both in the gas phase and in solution. According to X-ray analysis data in crystals, they exist only in Z,syn form too. Most of the phosphine oxide derivatives and 5-methoxy- and 5-bromoaryl phosphinate analogs exhibit anti-aggregant activity at the level of acetylsalicylic acid but inhibit platelet activation processes more effectively. The 5-chloro type phosphinate derivative exhibits anti-aggregant properties more effectively than acetylsalicylic acid under the conditions of the tissue factor (TF)-activated thromboelastography (TEG) model, the ex vivo thrombosis model. Thus, all the obtained results can become the basis for future pharmaceutical developments to create effective anti-aggregation drugs with broad antithrombotic potential. Full article

Bis- and trisphosphines incorporating methylene and aryl spacers readily adsorb on the surface of porous activated carbon (AC). The adsorption can be performed in the absence of solvents, even when the phosphines have high melting points, or from solutions. The diverse phosphines Ph₂PCH₂PPh₂ (dppm), Ph₂P(CH₂)₂PPh₂ (dppe), Ph₂P(CH₂)₃PPh₂ (dppp), Ph₂P(p-C₆H₄)PPh₂ (dppbz), and (Ph₂PCH₂)₃CCH₃ (tdme) were adsorbed in submonolayers on AC. The adsorbed phosphines were studied by ³¹P MAS (magic angle spinning) NMR spectroscopy, and their mobilities on the surface were confirmed by determining the ³¹P T₁ relaxation times. All phosphine groups of each bis- and trisphosphine molecule are in contact with the surface, and the molecules exhibit translational mobility as one unit. All phosphines used here are air-stable. Once a submonolayer is created on the AC surface, oxygen from the air is co-adsorbed and transforms all phosphines quantitatively into phosphine oxides at room temperature. The oxidation proceeds in a consecutive manner with the oxidation of one phosphine group after another until the fully oxidized species are formed. Studies of the kinetics are based on integrating the signals in the solution ³¹P NMR spectra. High temperatures and low surface coverages increase the speed of the oxidation, while light and acid have no impact. The oxidation is fast and complete within one hour for 10% surface coverage at room temperature. In order to study the mechanism and slow down the oxidation, a higher surface coverage of 40% was applied. No unwanted P(V) side products or water adducts were observed. The clean phosphine oxides could be recovered in high yields by washing them off of the AC surface. The oxidation is based on radical activation of O₂ on the AC surface due to delocalized electrons on the AC surface. This is corroborated by the result that AIBN-derived radicals enable the air oxidation of PPh₃ in solution at 65 °C. When the air-stable complex (CO)₂Ni(PPh₃)₂ is applied to the AC surface and exposed to the air, OPPh₃ forms quantitatively. The new surface-assisted air oxidation of phosphines adsorbed on AC renders expensive and hazardous oxidizers obsolete and opens a synthetic pathway to the selective mono-oxidation of bis- and trisphosphines. Full article

We report the synthesis of pyrrolo[3′,2′:3,4]fluoreno[9,1-gh]quinoline and pyrrolo[2′,3′,4′:4,10]anthra[1,9-fg]quinoline derivatives. This novel class of N-doped polycyclic heteroaromatic compounds was synthesized by a site-selective cross-coupling reaction followed by acid-mediated cycloisomerization and Pd-catalyzed CH arylation as the final ring-closing reactions. Preliminary optical and aromatic properties were studied by means of steady-state absorption and fluorescence spectroscopy and DFT calculation. Special emphasis was placed on the impact of ring alternation and position of the N-doping within the scaffold. Full article

Matrix metalloproteinase-9 (MMP-9) and lipopolysaccharide (LPS) levels are known to be elevated in obesity and contribute to metabolic dysfunction. 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), an endogenous ligand of the aryl hydrocarbon receptor (AhR), has been implicated in the regulation of inflammatory responses. This study aimed to determine whether ITE can inhibit LPS-induced MMP-9 expression in monocytic cells and to explore the underlying signaling mechanisms involved. Human monocytic THP-1 cells and primary human monocytes were treated with LPS in the presence or absence of ITE. MMP-9 mRNA and protein levels were assessed using quantitative real-time PCR and ELISA, respectively, while gelatin zymography was employed to evaluate MMP-9 enzymatic activity. Chromatin immunoprecipitation followed by qPCR (ChIP-qPCR) was performed to assess NF-κB and AP-1 binding to the MMP-9 promoter region. Our findings demonstrate that ITE significantly suppresses LPS-induced MMP-9 gene and protein expression. This suppression is associated with a marked reduction in LPS-induced NF-κB and AP-1 transcriptional activity. ChIP-qPCR confirmed that ITE attenuates the recruitment of NF-κB and AP-1 to the MMP-9 promoter, thereby inhibiting its transcription. In summary, ITE downregulates LPS-induced MMP-9 expression by interfering with NF-κB/AP-1 signaling, suggesting a potential anti-inflammatory mechanism that could be relevant in the context of MMP-9-driven inflammatory conditions. Full article

Metabolic dysfunction-associated fatty liver disease (MAFLD) represents a global health burden, however, therapeutic advancements remain hindered by incomplete insights on mechanisms and suboptimal clinical interventions. This review focused on the transcription factors (TFs) associated with the gut–liver axis, emphasizing their roles as molecular interpreters of systemic crosstalk in MAFLD. We delineate how TF networks integrate metabolic, immune, and gut microbial signals to manage hepatic steatosis, inflammation, and fibrosis. For instance, metabolic TFs such as peroxisome proliferator-activated receptor α (PPARα) and farnesoid X receptor (FXR) are responsible for regulating lipid oxidation and bile acid homeostasis, while immune-related TFs like signal transducer and activator of transcription 3 (STAT3) modulate inflammatory cascades involving immune cells. Emerging evidence highlights microbiota-responsive TFs, like hypoxia-inducible factor 2α (HIF2α) and aryl hydrocarbon receptor (AHR), linking microbial metabolite signaling to hepatic metabolic reprogramming. Critically, TF-centric therapeutic strategies, including selective TF-agonists, small molecules targeted to degrade TF, and microbiota modulation, hold considerable promise for treating MAFLD. By synthesizing these insights, this review underscores the necessity to dissect TF-mediated interorgan communication and proposes a roadmap for translating mechanism discoveries into precision therapies. Future research should prioritize the use of multi-omics approaches to map TF interactions and validate their clinical relevance to MAFLD. Full article