Search Results (152)

Background/Objectives: Chronic myeloid leukemia (CML) is primarily associated with the BCR:ABL1 fusion protein. Although tyrosine kinase inhibitors (TKIs) have markedly enhanced treatment outcomes, the development of agents with improved therapeutic characteristics remains necessary. The present work focused on the synthesis of a new series of thiazolone derivatives (F1-11) and the assessment of their anti-CML activity through inhibition of ABL tyrosine kinase (TK). Methods: The designed compounds were prepared through a multistep synthetic pathway involving the formation of a new chalcone intermediate (A), synthesis of a new pyrazoline carbothioamide intermediate (B), and cyclization with different aldehydes to produce the target new thiazolone derivatives (F1-11). Cytotoxic effects were investigated against K562 CML cells using the MTT assay. The lead compound was additionally evaluated in HL-60 AML cells and normal PBMCs. Apoptotic induction was analyzed using Annexin V/ethidium homodimer staining, whereas ABL TK inhibitory activity was measured through the ADP-Glo assay. Molecular docking studies were conducted to explore ligand interactions within the ATP-binding domain of ABL TK. Results: Among the synthesized molecules, F-4 demonstrated the strongest activity against K562 cells with an IC₅₀ value of 6.85 µM, close to that observed for imatinib (IC₅₀ = 5.20 µM). The compound showed reduced cytotoxicity toward HL-60 cells (IC₅₀ = 33.44 µM) and exhibited favorable selectivity toward PBMCs (SI = 13). Apoptosis studies revealed 51% early apoptotic cells and 43% late apoptotic cells following treatment. In the kinase assay, F-4 inhibited ABL TK activity by 39% at 10 µM and by 70% at 100 µM. Docking simulations suggested interactions with residues His361 and Asp381 in addition to nearby hydrophobic amino acids, although the interaction network was less extensive than that of imatinib. Conclusions: The findings identify F-4 as a promising new thiazolone-derived scaffold with selective anti-CML activity and notable ABL TK inhibitory potential. Additional structural optimization may further enhance its binding characteristics and therapeutic efficacy. Full article

Background: Cancer patients are highly susceptible to microbial infections due to immune suppression, necessitating therapeutic strategies that integrate anticancer efficacy with effective antimicrobial intervention. Chalcone-derived nitrogen-fused heterocycles represent a promising platform for developing multi-target agents with relevance to antimicrobial drug delivery, particularly for localized infections. Methods: A series of chalcone-based pyrazoline-thiadiazole nitrogen-fused azole hybrids was synthesized via thiosemicarbohydrazide-functionalized intermediates and fully characterized. Antiproliferative activity was evaluated against MCF-7, HepG-2, HeLa, and HCT-116 cell lines, alongside selectivity toward WI-38 normal fibroblasts. Antibacterial, antibiofilm, and in vivo efficacy were assessed against methicillin-resistant Staphylococcus aureus (MRSA USA300) and Acinetobacter baumannii AB5057. Mechanistic investigations included cell-cycle analysis, apoptosis assays, ERK2, RIPK3, p53, BAX/Bcl-2 quantification, DNA gyrase inhibition, molecular docking, molecular dynamics simulations, and density functional theory calculations. Results: Compound 13 exhibited potent cytotoxicity, particularly against MCF-7 (IC₅₀ = 3.87 ± 0.2 µM), outperforming doxorubicin (IC₅₀ = 4.17 ± 0.2 µM), with high selectivity indices (SI = 10.7 for MCF-7). Mechanistically, compound 13 induced G₂/M arrest (40.16% vs. 14.15% control), increased apoptosis to 32.89%, up-regulated ERK2 (3.17-fold), RIPK3 (11.97-fold), and p53 (3.54-fold), and markedly increased the BAX/Bcl-2 ratio (~42-fold). Compounds 7 and 13 displayed bactericidal activity against MRSA and A. baumannii (MIC/MBC = 10 mg/mL), potent antibiofilm effects, and significant in vivo efficacy in an MRSA skin infection model. Compound 13 reduced bacterial load by ~5 log units, outperforming vancomycin. DNA gyrase inhibition (IC₅₀ = 17.10 ± 0.17 µM) and computational studies supported target engagement. Conclusions: Pyrazoline-thiadiazole-based nitrogen-fused azole hybrids, particularly compound 13, demonstrated quantifiable anticancer and antimicrobial efficacy with strong in vivo validation, supporting their potential as multi-target candidates relevant to antimicrobial drug delivery in infection-prone cancer patients. Full article

This study explores the multifaceted anticancer mechanisms of flavanone analogues and spiropyrazoline condensed with flavanone ring against colorectal cancer (CRC) cell lines. Five-membered heteroaromatic scaffolds, in particular, have gained prominence in medicinal chemistry as they offer enhanced metabolic stability, solubility and bioavailability, crucial factors in developing effective drugs. Building upon previous findings, we investigated three lead derivatives (1, 3, and 5) with potent antiproliferative activity (IC₅₀ < 35 μM). The compounds induced pronounced oxidative stress, evidenced by increased lipid peroxidation and reduced membrane fluidity, primarily within the hydrophobic layers of cell membranes. Preincubation with the antioxidant N-acetylcysteine (NAC) significantly attenuated these effects, confirming the pivotal role of reactive oxygen species (ROS) in their cytotoxicity. Mechanistic studies revealed that the derivatives triggered intrinsic apoptosis, characterized by the cleavage of PARP and the activation of caspase-9 and caspase-3. Furthermore, the compounds modulated key signaling pathways involved in cell survival and proliferation. Specifically, they inhibited the pro-oncogenic ERK1/2 MAPK pathway while inducing cell line-dependent alterations in p38 and JNK activity. Concurrently, all derivatives reduced the level of the transcription factor Nrf2, a master regulator of antioxidant defense and a mediator of chemoresistance in CRC. Collectively, these findings indicate that flavanone/chromanone derivatives exert their anticancer activity through a synergistic mechanism involving ROS generation, disruption of redox homeostasis, inhibition of Nrf2 signaling, and modulation of MAPK-dependent apoptotic pathways. These results highlight the therapeutic potential of flavanone-based compounds and their spiropyrazoline analogues as multifunctional anticancer agents targeting oxidative stress and survival signaling in colorectal cancer. Full article

1,3-Dipolar cycloaddition reactions of nitrile imines are a powerful tool for the construction of spirocyclic frameworks, yet controlling chemoselectivity remains challenging when dipolarophiles contain multiple reactive sites. In this study, we investigated the cycloaddition of nitrile imines with 5-arylmethylene-2-methylthiohydantoins, which possess both exocyclic C=C and endocyclic C=N bonds. Nitrile imines were generated from hydrazonoyl chlorides under basic conditions and reacted with the thiohydantoin substrates under optimized reaction conditions. The cycloaddition proceeded smoothly, affording spiro-fused thiohydantoin–pyrazoline derivatives. In all cases, the reaction occurred selectively at the exocyclic C=C bond, while the C=N bond remained unreactive even in the presence of excess dipole. This chemoselectivity is attributed to the greater steric accessibility of the exocyclic double bond. These results clarify key factors governing nitrile imine chemoselectivity and provide a reliable approach to structurally complex spirocyclic thiohydantoin derivatives. Full article

A strategy for constructing trifluoromethylated spiroisoxazolones has been developed. This approach relies on the 1,3-dipolar cycloaddition of CF₃-substituted nitrile imines, generated in situ from trifluoroacetyl hydrazonoyl bromides and K₂CO₃, with the exocyclic double bond of 4-benzylidene-3-methylisoxazol-5(4H)-ones. The reaction provides a series of trifluoromethylated spiro(isoxazolone-pyrazoline) derivatives in moderate to high yields (up to 93%). The protocol exhibits broad substrate compatibility with respect to aromatic substituents on both reaction partners. To the best of our knowledge, the introduction of a trifluoromethyl group at the 3-position of the pyrazoline ring via nitrile imine cycloaddition chemistry has not been previously reported. The resulting products incorporate a valuable CF₃-substituted pyrazoline pharmacophore spiro-fused to an isoxazolone core and may be of interest for medicinal chemistry programs. Full article

Concurrent evaluation of the antiparasitic efficacy of synthetic and natural compounds can provide novel insights into the development of anti-Toxoplasma drugs. We assessed 16 synthetic compounds and two fractions derived from the leaves of Tabebuia rosea and Tabebuia chrysantha tree species for their in vitro activity against live parasites, employing strains that express green fluorescent protein and specific identification of bradyzoites using an anti-BAG1 monoclonal antibody. This study successfully identified several promising synthetic compounds with potent anti-Toxoplasma activity and favorable in vitro selectivity profiles, notably pyrazoline 2 and thiazolidinone 9. One thiazolidinone compound exhibited significant activity against extracellular tachyzoites, whereas one tree fraction demonstrated excellent activity against both tachyzoites and bradyzoites. Additionally, their in silico ADMET properties suggest their potential for good in vivo performance and CNS penetration. Although the natural extracts showed less potency in their crude form, they provide a basis for future purification efforts. The simultaneous evaluation of compounds sourced from diverse discovery pipelines can offer valuable insights into the development of drugs that target various biological pathways. Full article

Background/Objectives: Breast cancer remains one of the most prevalent and life-threatening malignancies worldwide. This study describes the design and biological evaluation of a series of secosteroid–2-pyrazoline hybrids as novel antitumor agents against ERα-positive breast cancer cell lines MCF-7 and T47D. Methods: A simple and efficient method for synthesizing secosteroid–2-pyrazoline hybrids was developed starting from 13α-hydroxy-3-methoxy-13,17-secoestra-1,3,5(10)-triene-17-oic acid hydrazide and 1,3-diketones. The resulting secosteroid derivatives were evaluated against hormone-dependent MCF-7 and T47D breast cancer cells. Furthermore, the selectivity and effects of three lead compounds on signaling pathways in MCF-7 cells were examined. Flow cytometry was used to assess the cell-cycle distribution of MCF-7 cells treated with the lead compound. Results: Among the synthesized hybrids, compounds 3f, 3j, and 3k exhibited potent antiproliferative activity with IC₅₀ values of 0.2–0.5 μM against breast cancer cells, while demonstrating very low cytotoxicity towards normal cells (IC₅₀ > 25 μM), indicating a favorable safety profile. The antitumor activity of lead compound 3j was additionally investigated in combination with standard chemotherapeutics, docetaxel and doxorubicin, yielding synergistic effects. The lead compounds showed a dual mechanism of action by inhibiting S6 kinase and promoting Bcl-2 phosphorylation at 0.9 μM, without significantly affecting hormonal breast cancer targets such as ERα, GREB1, and AR. Compound 3j induced apoptosis accompanied by a reduction of the G1/G0 phase in MCF-7 cells. Conclusions: These findings highlight secosteroid–2-pyrazoline hybrids as promising candidates for the development of next-generation breast cancer therapeutics targeting apoptosis and S6K signaling pathways. Full article

Fused and spiro nitrogen-containing heterocycles play an important role as structural motifs in numerous biologically active natural products and pharmaceuticals. The review summarizes various approaches to the synthesis of three-, four-, five-, and six-membered fused and spiro heterocycles with one or two nitrogen atoms. The assembling of the titled compounds via cycloaddition, oxidative cyclization, intramolecular ring closure, and insertion of sextet intermediates—carbenes and nitrenes—is examined on a vast number of examples. Many of the reactions proceed with high regio-, stereo-, or diastereoselectivity and in excellent, up to quantitative, yield, which is of principal importance for the synthesis of chiral drug-like compounds. For most unusual and hardly predictable transformations, the mechanisms are given or referred to. Full article

Estrogen receptor alpha (ERα) plays a vital role in the development and progression of breast cancer by regulating the expression of genes associated with cell proliferation in breast tissue. ERα inhibition is a key strategy in the prevention and treatment of breast cancer. Previous research modified chalcone compounds into pyrazoline benzenesulfonamide derivatives (Modifina) which show activity as an ERα inhibitor. This study aimed to design novel pyrazoline benzenesulfonamide derivatives (PBDs) as ERα antagonists using in silico approaches. Structure-based and ligand-based drug design approaches were used to create drug target molecules. A total of forty-five target molecules were initially designed and screened for drug likeness (Lipinski’s rule of five), cytotoxicity, pharmacokinetics and toxicity using a web-based prediction tools. Promising candidates were subjected to molecular docking using AutoDock 4.2.6 to evaluate their binding interaction with ERα, followed by molecular dynamics simulations using AMBER20 to assess complex stability. A pharmacophore model was also generated using LigandScout 4.4.3 Advanced. The molecular docking results identified PBD-17 and PBD-20 as the most promising compounds, with binding free energies (ΔG) of −11.21 kcal/mol and −11.15 kcal/mol, respectively. Both formed hydrogen bonds with key ERα residues ARG394, GLU353, and LEU387. MM-PBSA further supported these findings, with binding energies of −58.23 kJ/mol for PDB-17 and −139.46 kJ/mol for PDB-20, compared to −145.31 kJ/mol, for the reference compound, 4-OHT. Although slightly less favorable than 4-OHT, PBD-20 demonstrated a more stable interaction with ERα than PBD-17. Furthermore, pharmacophore screening showed that both PBD-17 and PBD-20 aligned well with the generated model, each achieving a match score of 45.20. These findings suggest that PBD-17 and PBD-20 are promising lead compounds for the development of a potent ERα inhibitor in breast cancer therapy. Full article

EGFR is the most frequently altered driver gene in non-small-cell lung cancer (NSCLC), and its overexpression is also associated with breast cancer. In the present study, we synthesized 18 new compounds (B-1, B-2, B-6, B-7, and BP-1–14). The cytotoxicity of these compounds was evaluated in A549 NSCLC and MCF-7 breast cancer cells, as well as in Jurkat cells and PBMCs (healthy). The most potent compounds were further examined for their ability to induce apoptosis in A549 and MCF-7 cells, as well as their EGFR inhibitory activity. Molecular docking was conducted at the ATP-binding site of EGFR, and key pharmacokinetic and toxicity parameters were predicted in silico. B-2 demonstrated the strongest cytotoxicity against A549 and MCF-7 cells (IC₅₀ = 2.14 ± 0.83 μM and 8.91 ± 1.38 μM, respectively), displaying selective cytotoxicity between Jurkat cells and PBMCs (SI = 23.2). B-2 induced apoptosis in A549 and MCF-7 cells at rates of 16.8% and 4.3%, respectively. B-2 inhibited EGFR by 66% at a 10 μM concentration and showed a strong binding affinity to the ATP-binding site of EGFR. Furthermore, B-2 exhibited drug-like characteristics and was not identified as carcinogenic, genotoxic, or mutagenic. B-2 shows promise as an apoptosis inducer and EGFR inhibitor for future anti-NSCLC and anti-breast cancer research. Full article

Nitrogen-containing heterocycles are fundamental scaffolds in organic chemistry, particularly due to their prevalence in pharmaceuticals, agrochemicals and materials science. Among them, five-membered rings, containing two nitrogen atoms in adjacent positions—such as pyrazoles, pyrazolines and indazoles—are especially significant due to their versatile biological activities and structural properties, which led to the search for greener, faster and more efficient methods for their synthesis. Conventional batch synthesis methods, while effective, often face challenges related to reaction efficiency, scalability and safety. Flow chemistry has emerged as a powerful alternative, offering enhanced control over reaction parameters, improved safety profiles and opportunities for scaling up synthesis processes efficiently. This review explores the impact of flow chemistry on the synthesis of these pivotal heterocycles, highlighting its advantages over the conventional batch methods. Although indazoles have a five-membered ring fused with a benzene ring, they will also be considered in this review due to their biological relevance. Full article

The world today is being ravaged by the emergence and re-emergence of microbial infections caused by antimicrobial-resistant strains, brought about primarily by the frequent and perhaps unnecessary use of antimicrobial agents. A need therefore arises to develop new antimicrobial drugs that can combat these pathogens resistant to currently available antibiotics. This present study has adopted a multi-enzyme in silico approach in evaluating new 2-pyrazolines as antimicrobial agents, targeting and aiming to inhibit three pivotal enzymes in the bacteria’s life cycle. A library of 2-pyrazolines was tailored to achieve the desired activity. The library of compounds and amoxicillin, a standard antimicrobial drug, were docked into the molecular target enzymes. They were also subjected to toxicity and drug-likeness tests, using PROTOX and swissADME, respectively. A moderate toxicity profile was indicated, as more than 90% of the ligands were in ProTox class 4. The majority exhibited advantageous ADME characteristics. A significant number of them demonstrated a binding affinity for the target proteins that was stronger than both the native ligand and the binding affinity of amoxicillin. Ligands 30, 20, and 8 are the notable ones across all target enzymes. These results suggest that these novel ligands may be powerful inhibitors, particularly when it comes to interfering with the formation of bacterial cell walls, folic acid, and nucleotide metabolism. Additional in vivo and in vitro research is required to confirm these results and evaluate their therapeutic potential. Full article

Background: Despite recent breakthroughs in cancer treatment, non-small cell lung cancer (NSCLC) and breast cancer remain major causes of death from all malignancies. The epidermal growth factor receptor (EGFR) is an important mediator of the pathways involved in cell proliferation, apoptosis, and angiogenesis. Thus, its overexpression triggers several types of cancer, including NSCLC and breast cancer. Methods: In the current study, we synthesized new pyrimidine-tethered compounds (chalcone derivative (B-4), pyrazoline–carbothioamide (B-9), and pyrazoline–thiazole hybrids (BH1-7)). These compounds were then tested for cytotoxicity against A549 NSCLC and MCF-7 breast cancer cells. Results: Of these, B-4 displayed significant cytotoxicity against both cells (IC₅₀ = 6.70 ± 1.02 µM for MCF-7; IC₅₀ = 20.49 ± 2.7 µM for A549) compared to the standard agent lapatinib (IC₅₀ = 9.71 ± 1.12 µM for MCF-7; IC₅₀ = 18.21 ± 3.25 µM for A549). The anticancer potential of B-4 between Jurkat leukemic T cells and peripheral blood mononuclear cells (PBMCs) (healthy) was found to be selective. Mechanistically, 11.9% and 10.2% of A549 and MCF-7 cells treated with B-4, respectively, underwent apoptosis and B-4 produced 46% EGFR inhibition at a concentration of 10 μM. The B-4/EGFR complex obtained after induced fit docking was subjected to 300 ns of molecular dynamics simulation, which confirmed the stability of the complex in a mimicked biological environment. On the other hand, B-4 was shown to have drug-like properties by in silico pharmacokinetic estimation. Conclusions: B-4 is an EGFR inhibitor and apoptosis inducer for future NSCLC and breast cancer studies. Full article

The synergistic solvent extraction of La(III), Eu(III) and Lu(III) with a chelating extractant, 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one (HL), and neutral bidentate heterocyclic amines, such as 1,10-phenanthroline (S1 (phen)) or 2,2′-bipyridine (S2 (bipy)) in an ionic liquid of the imidazolium family [C₁C₄im⁺][Tf₂N⁻] was investigated. Synergistic effects have been observed to result from the formation of a ternary complex in the organic phase, particularly in cases where the ligand S is a neutral synergistic agent. Examples include La(L)₂(S2)₂, Eu(L)₃(S2) and Lu(L)_x(S2)₂, as well as La(L)₃(S1)₂, Eu(L)₂(S1) and Lu(L)₃(S1)_x). The parameters of the solvent extraction process were determined and the influence of the synergistic agent on the extraction process was discussed. Additionally, the synergistic increase and separation factors were determined. The equilibrated organic phases were analyzed using ¹H NMR spectroscopy to elucidate the synergism in an extraction mechanism. The role of the ionic diluent in complexation processes and selectivity was investigated with the employment of the two synergistic agents for various metal s-, p-, d- and f-cations in the periodic table, with almost 22 metal ions. Full article

In this paper, we report a highly regioselective 1,3-dipolar cycloaddition (1,3-DC) reaction of nitrilimines with thioaurone derivatives that afforded the hitherto unreported spiropyrazolines. Spectroscopic and spectrometric data were utilized to confirm the structure of all products and elucidate the reaction’s regiochemistry. A mechanistic study was performed within the Molecular Electron Density Theory (MEDT) at the B3LYP/6-311G(d,p) computational level to explain the regioselectivity observed. The electron localization function (ELF) topological analysis confirms the carbenoid-type (cb-type) mechanism of the cycloaddition reactions between nitrilimines and thioaurones. The intermolecular interactions between reagents in this reaction account for the regioselectivity observed experimentally. Full article