Exportin 1 (XPO1/CRM1) is a clinically validated anticancer target whose inhibition blocks nuclear export and promotes cancer cell apoptosis. Current XPO1 inhibitors rely on covalent Michael addition to Cys528 in the nuclear export signal binding groove of XPO1. Here, we describe a novel XPO1 inhibitor, FR-027, that targets Cys528 through nucleophilic aromatic substitution. In contrast to clinical-stage XPO1 inhibitors selinexor and eltanexor, FR-027 acts reversibly and does not promote XPO1 protein degradation. Structural analysis of the XPO1-FR-027 complex reveals covalent modification of Cys528 and a closed-groove conformation that prevents degradation. FR-027 demonstrates potent on-target activity across multiple cancer cell types and delays disease progression while extending overall survival in xenograft and syngeneic models, including intracranial tumors. Notably, FR-027 does not induce significant thrombocytopenia, lymphopenia, or neutropenia in heavily treated mice. These findings underscore the distinct molecular and pharmacological properties of FR-027 and support its further evaluation for clinical development in diseases with significant unmet medical needs.

Herein, we report the design and synthesis of C6-substituted purine and 7-deazapurine isoxazole derivatives via 1,3-dipolar cycloaddition, followed by microwave-assisted Suzuki-Miyaura and Sonogashira cross-coupling reactions. Selected pyridine-isoxazole ligands were coordinated to fac-[Re(CO)5Cl], and the resulting Re(I) tricarbonyl complexes were characterized by UV-Vis, IR, NMR spectroscopy, and elemental analysis. The structure of complex 8aRe was confirmed by single-crystal X-ray diffraction analysis, revealing facial coordination of the carbonyl ligands and distorted octahedral geometry around the rhenium center. Antiproliferative activity of all compounds was evaluated across eight human cancer cell lines. Structure-activity relationship analysis demonstrated that arylalkynyl substitution at the C-6 position of purine and 7-deazapurine scaffolds significantly enhances antiproliferative potency, whereas directly arylated derivatives were largely inactive. Among the ligands, compound 6b emerged as the most potent, displaying low-micromolar IC50 values against pancreatic cancer Capan-1, T-cell leukemia DND-41, acute myeloid leukemia HL-60, and non-Hodgkin lymphoma Z-138 cell lines (IC50 = 1.5-2.1 mu M). Although these potencies are promising, selectivity toward nonmalignant cells remained moderate (SI = 3.7-4.8), indicating that further optimization is required. Rhenium coordination further increased antiproliferative activity but also reduced selectivity, with complex 8bRe showing consistent low-micromolar potency across the same cell lines (IC50 = 1.6-1.9 mu M, SI = 1.5-1.8). Molecular docking and in silico ADME analyses indicated favorable drug-like properties and suggested the STAT3 SH2 domain as a possible molecular target for both 6b and 8bRe, supporting their potential as promising lead compounds for selectivity improvement and further anticancer development.

Glioblastoma (GBM) is an aggressive primary brain tumor with a major unmet medical need. Oncolytic viruses (OVs) show promise for GBM treatment, but complete remissions remain rare. The intratumoral heterogeneity of GBM drives therapeutic escape and emergence of OV-resistant subclones. Beyond the well-characterized interferon-mediated antiviral response, mechanisms driving OV resistance remain poorly understood. To identify new markers of tumor-intrinsic OV resistance in GBM, we exposed 14 GBM patient-derived cell lines (GBM-PDCLs) to 6 OVs and generated virus-resistant subpopulations from surviving cells. Focusing on Sindbis (SINV)- and H1-parvovirus (H1PV)-resistant cells, we showed that resistance is associated with impaired viral replication. Gene set enrichment analysis of transcriptomic profiles revealed that resistance to both SINV and H1PV correlated with downregulated glutamate receptor signaling. In contrast, collagen fibril organization was downregulated in SINV-resistant GBM PDCLs but upregulated in H1PV-resistant cells. Functional validation confirmed opposing effects of collagen degradation on SINV and H1PV oncolytic activity. One SINV-resistant GBM-PDCL showed cross-resistance to multiple OVs, which was associated with increased expression of antiviral immunity genes and increased dependence on type I interferon signaling for survival. Together, these findings reveal shared and virus-specific cellular processes driving OV resistance in GBM, providing a basis for strategies to overcome resistance.

Glioblastoma (GBM) is the most aggressive primary brain tumor in adults characterized by poor long-term survival and frequent tumor recurrence, highlighting the urgent need for novel therapeutic strategies. Oncolytic viruses (OVs) preferentially infect and kill cancer cells while stimulating an antitumor immune response. Oncolytic virotherapies have shown encouraging results in preclinical GBM models and some clinical settings. However, high tumor heterogeneity poses a major obstacle. Only a subset of GBM patients responds well, and improvement in survival is usually limited. It is therefore crucial to better understand determinants of OV effectiveness and to consider multiple OVs. Here, we report a comparative analysis of the oncolytic efficacy of 15 clinically relevant viruses across a diverse panel of 14 heterogeneous patient-derived GBM cell lines. Correlation analysis revealed two clusters of viruses with opposing oncolytic activity profiles and opposing preferences for GBM subtypes. Oncolytic activities correlated with expression levels of interferon-, neurodevelopment-, and extracellular matrix-related gene sets, with inverse correlations observed between the two OV groups. Together, these data reveal that diverse viruses share similar determinants of oncolytic activity. Our findings pave the way toward combinatorial or personalized OV therapies in GBM, where tumor subtype could guide selection of the most effective OV.

Introduction Benzoxazole is a privileged scaffold with diverse biological activities, and its hybridization with a 1,2,3-triazole ring can improve affinity and efficacy. This study aimed to synthesize novel 1,2,3-triazole derivatives of 2-aminobenzoxazole and 2-mercaptobenzoxazole, and to evaluate their antiproliferative activity, predicted pharmacokinetic properties, and molecular interactions with kinase targets.Methods 1,2,3-triazole derivatives of 2-aminobenzoxazole 3-15 and 2-mercaptobenzoxazole 18-32 were synthesized via cyclization, propargylation, and copper-catalyzed click reaction. Antiproliferative activity was evaluated against human cancer cell lines: LN-229, Capan-1, HCT-116, NCI-H460, DND-41, HL-60, K-562, and Z-138. The ADME properties of 1,2,3-triazole-benzoxazole hybrids were evaluated using the SwissADME tool. The most active compounds were assessed for Human Gastrointestinal Absorption (HGA) and Blood-Brain Barrier (BBB) permeability using the Egan model. Molecular docking was performed on serine/threonine kinase TAO2 and tyrosine kinase c-Src.Results A series of novel 1,2,3-triazole derivatives of 2-amino 3-15 and 2-mercaptobenzoxazole 18-32 were synthesized via click chemistry. Coumarin-containing compounds 3 and 29 showed the most pronounced antiproliferative activity across all tested cell lines. Both demonstrated high predicted HGA and low likelihood of crossing the BBB. Compound 3 exhibited the highest binding affinity for TAO2, while compound 29 showed strong interaction with c-Src.Discussion The results highlight the favorable influence of coumarin substitution on antiproliferative activity, with computational ADME and docking data supporting the observed in vitro efficacy.Conclusion This study outlines a viable method for the synthesis of novel 1,2,3-triazole derivatives of 2-aminobenzoxazole and 2-mercaptobenzoxazole. Compounds 3 and 29 demonstrate promising antiproliferative activity and pharmacokinetic potential, supporting their further development as anticancer candidates.

Deficiency of adenosine deaminase 2 (DADA2) causes a complex phenotype of autoinflammation and immunodeficiency. Bone marrow failure is often refractory to treatment with tumour necrosis factor-alpha (TNF-alpha) inhibitors and additional treatment options are needed. However, the pathomechanisms underlying the disease remain incompletely understood. The aim of this study was to examine the viability and metabolic profile of ADA2-deficient cells and to characterise the activity of different cell death pathways to advance the mechanistic understanding of DADA2. By flow cytometry and western blot, we showed that ADA2-/- U-937 cells and PBMCs from DADA2 patients showed significantly elevated levels of cell death compared with cells expressing wild-type ADA2. Viability of ADA2-deficient cells was not improved by inhibitors of apoptosis, necroptosis, pyroptosis and ferroptosis. Blocking of TNF-alpha, type I interferon and STING signalling as well as reintroduction of wild-type ADA2 protein did not rescue the cell death phenotype in vitro. ADA2-deficient cells had an aberrant morphology with increased cell size and granularity and were impaired in their proliferative capacity. To identify the cause of the impaired viability, we performed 13C glucose tracer metabolomics experiments which revealed disturbances in the pentose phosphate pathway of ADA2-deficient cells. This tended to be associated with increased exposure to intracellular reactive oxygen species that was attenuated in the PBMCs of a DADA2 patient measured after successful hematopoietic stem cell transplantation. Collectively, our findings established increased levels of cell death as a possible pathomechanism of DADA2 and showed that the absence of ADA2 leads to an impairment of the pentose phosphate pathway which may account for the cellular vulnerability of ADA2-deficient cells.

A series of hybrid molecules containing indole and 1,3,5-triazine scaffolds was synthesized and evaluated for their antiviral activity against several human RNA and DNA viruses. The conjugates displayed overall low cytotoxicity (CC50 > 50 µM) and potent antiviral activity across a coronavirus panel, with the most promising analogs (compounds 5d, 5g and 5o) showing sub- to low-micromolar EC50 values against HCoV-OC43, HCoV-229E, and SARS-CoV-2. Structure-activity relationship studies highlighted that the substitution pattern on the anilino moiety allowed to modulate antiviral activity. Time-of-drug addition, adsorption, and fusion assays indicated inhibition of viral replication at an early viral entry step, consistent with inhibition of spike-mediated membrane fusion. Overall, these data suggest that 1,3,5-triazine-indole conjugates are a promising scaffold to develop broad-spectrum coronavirus entry inhibitors. ADMET profiling of lead compounds (5d, 5g, and 5o) revealed favorable pharmacokinetic properties, including high oral absorption, limited CNS penetration, and non-mutagenic safety profiles.

A novel series of benzoxazole-derived iminocoumarins was synthesized via a Knoevenagel condensation and fully characterized using NMR, UV–Vis spectroscopy, and computational methods. Their photophysical properties were systematically examined in solvents of varying polarity, revealing pronounced effects of both substituents and solvent environment on absorption maxima and intensity. Derivatives bearing electron-donating substituents on the coumarin core exhibited distinct and reversible pH-responsive spectral shifts, confirming their potential as optical pH probes. Experimental pKa values derived from absorption titrations showed excellent agreement with DFT-calculated data, validating the proposed protonation-deprotonation equilibria and associated electronic structure changes. Structure–property relationships revealed that electron-donating groups enhance intramolecular charge transfer, while electron-withdrawing substituents modulate spectral response and stability. In parallel, the compounds were evaluated for antiproliferative, antiviral, and antifungal activities in vitro. Strong electron-donating substituents were associated with potent but non-selective cytotoxicity, whereas derivatives bearing electron-withdrawing groups displayed moderate and more selective antiproliferative effects against leukemia cell lines. Antifungal screening revealed moderate inhibition of phytopathogenic fungi, particularly for compounds with electron-withdrawing or methoxy substituents. Overall, these findings demonstrate that benzoxazole iminocoumarins represent a promising class of multifunctional heterocycles with potential applications as optical pH sensors and scaffolds for bioactive compound development.

We report the synthesis of a series of 15 uridine analogues bearing a 1-substituted-1,2,3-triazole at the C5 position of the uracil moiety, along with the preparation of the corresponding phosphoramidate (ProTide) prodrugs. Key step is the regioselective copper-catalyzed azide-alkyne cycloaddition (CuAAC) under microwave irradiation, followed by conversion to the ProTide-type nucleotide prodrugs by reaction with pentafluorophenyl phosphoramidates s. The newly synthesized compounds were evaluated in vitro for antiviral activity against representative DNA viruses (vaccinia virus and herpes simplex virus type 1) and RNA viruses, including human coronavirus HCoV-OC43, Zika virus, Ross River virus, respiratory syncytial virus, and influenza A virus (H1N1). In addition, anticancer activity was assessed against a panel of human cancer cell lines, encompassing pancreatic, colorectal, hematological, brain, lung, neuroblastoma and mantle cell lymphoma models. Among the tested compounds, derivative 23n exhibited antiviral activity against HCoV-OC43 in HEL-299 cell cultures with an IC50 value of 6.45 & micro;M. Several analogues (23a, 23b, 23c and 23m) inhibited proliferation of Z138 mantle cell lymphoma cells with IC50 values in the 4.2-5.4 & micro;M range. Notably, compound 23c also demonstrated activity against Molt-4 and HL60 leukemia cell lines, with IC50 values of 4.53 & micro;M and 4.84 & micro;M, respectively.

This work presents a sustainable synthesis and comprehensive characterization of a novel series of benzothiazolesubstituted azo dyes. Their dyeing performance on synthetic fibers and biological activities, including anti-proliferative and antibacterial effects, were evaluated. Substituent variations on the benzothiazole ring significantly influenced both chromophoric behavior and bioactivity. Dyes 1-3 exhibited superior wash fastness on polyester (PES), while dyes 4-6 performed better on polyamide (PA). Dye 1 showed the least color change on PES (Delta E = 0.9), while dye 6 on PA (Delta E = 0.3). Overall, PA fabrics showed higher dye uptake, supported by K/S values. Compounds 4 and 5 displayed strong antiproliferative activity, particularly against pancreatic adenocarcinoma (Capan-1), with low micromolar IC50 values, while dyes 2 and 3 exhibited moderate antibacterial activity against an efflux-deficient E. coli strain. Single-crystal X-ray diffraction confirmed the E-configuration and highly delocalized pi-electron systems of dyes 1-3. The O-H & sdot;& sdot;& sdot;O, O-H & sdot;& sdot;& sdot;N and C-H & ctdot;O hydrogen bonds, as well as C-H & sdot;& sdot;& sdot;pi interactions in 2 and 3 and pi-pi interactions in 1 built three-dimensional network. These results highlight the potential of benzothiazole-based azo dyes as multifunctional agents for both textile and biomedical applications.

Respiratory syncytial virus (RSV) is an RNA virus that infects both the upper and lower respiratory tract and is recognized as a major respiratory health threat. In this study, guided by the cryo-EM structure of the MRK-1-RSV polymerase complex, the substituent region at the C4 position of the shared pyridine core was redesigned. A series of 32 pyridine carbohydrazide derivatives bearing structurally diverse N-substituted amino groups was synthesized to explore the structure-activity relationship and substituent tolerance of the adjacent pocket region. LX1 was selected as a representative compound for further investigation and exhibited potent activity against RSV-A Long strain, with an EC50 value of 37 nM. Minigenome assays showed that LX1 reduces polymerase-dependent reporter activity, consistent with inhibiting RSV RNA synthesis. Furthermore, molecular dynamics simulations revealed that LX1 forms stable hydrogen bonds and π-π stacking interactions with key amino acids in the PRNTase domain. Collectively, LX1 represents a promising lead compound for the further development of novel RSV inhibitors.

A series of benzothiazole acetamide hydrazones (8a-p) was synthesized and evaluated for anti-proliferative activity against various human cancer cell lines, including a pancreatic ductal adenocarcinoma (CAPAN-1), a colorectal carcinoma (HCT-116), a leukemia (HL60), a glioblastoma (LN229), a T lymphoblast (Molt-4), a non-small cell lung cancer (NCI-H460), and a B lymphoblast (Z138) cell line. Among the tested derivatives, compounds 8l, 8n, and 8o emerged as lead compounds, exhibiting cytotoxicity across multiple cell lines. Notably, compound 8o demonstrated selective cytotoxicity towards Z138 and LN229 cell lines, with IC50 values of 3.75 ± 1.44 and 4.39 ± 0.49 µM, respectively. The most active compounds in in vitro analysis exhibited the highest binding affinity in molecular docking studies. Compound 8o revealed effective binding to topoisomerase IIα (TOPO IIα) having an affinity of -9.7 kcal mol-1. Compound 8n displayed extended-target engagement, with the highest number of binding interactions inside the active pocket of TOPO IIα with an affinity of -9.9 kcal mol-1, along with the highest softness value (0.69 eV-1), underscoring its potential as a promising anti-cancer candidate corresponding to its broad spectrum in vitro cytotoxicity profile. The electronic properties, and pharmacokinetic behavior of the synthesized compounds were assessed through comprehensive in silico DFT (Density Functional Theory) and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) analysis, supporting their candidacy for further development as anti-cancer therapeutics.

Tetrachloridoferrate-based ionic liquids represent an emerging class of functional materials with promising magnetic and biological properties, yet their potential as photosensitizers and anticancer agents remains underexplored. We report the synthesis of new imidazole-based tetrachloridoferrate(iii) salts and a comprehensive evaluation of their structural, magnetic, photochemical, and cytotoxic properties. The target ionic liquids were prepared through the quaternization of imidazole derivatives, followed by anion exchange with FeCl3. Structural analysis via single-crystal X-ray diffraction of selected compounds revealed distinct non-covalent interaction patterns and charge distribution governing stability, while magnetic measurements demonstrated weak antiferromagnetic exchange interactions along the tetrachloridoferrate chains. Furthermore, ESP experiments revealed efficient photosensitized singlet oxygen generation under UV irradiation, which correlates with photodegradation of bisphenol A. Biological evaluation across a broad panel of solid and haematological cancer cell lines identified remarkable, selective cytotoxicity toward the LN229 glioblastoma cell line, with IC50 values as low as 0.70-1.50 µM, while no significant activity was observed against other glioblastoma models or normal PBMCs. These findings highlight imidazolium tetrachloridoferrates as compelling candidates for further investigation in oxidative-stress-based anticancer strategies.

Resistance to conventional therapies in pancreatic and hematologic malignancies highlights the need for novel agents that selectively induce tumor cell death. This study presents the design, synthesis, and evaluation of new quinoline- and coumarin-derived isoxazole analogs (7a-e, 8a-f, 9a-e) and their Re(i) and Ru(ii) complexes (7bRe, 9bRe, 7bRu, 9bRu). Antiproliferative assays against eight human cancer cell lines and noncancerous PBMCs identified quinoline amidoxime 8f as particularly potent, with IC50 values of 2.1-4.7 µM against hematologic cancers (DND-41, HL-60, Z-138) and pancreatic adenocarcinoma (Capan-1), with selectivity indices of up to 48. Permeability and metabolic stability studies showed high membrane permeability and moderate clearance for 8f. Molecular docking, validated by redocking of J1Q (PDB ID: 6QGK), confirmed that 8f forms stable, energetically favorable complexes with Bcl-2 (ΔG_bind = -84.98 kcal mol-1). These results support 8f as a promising lead compound for further development as a selective Bcl-2-targeted anticancer agent.

Adult T-cell leukemia (ATL), an aggressive malignancy triggered by human T-cell leukemia virus-1 (HTLV-1), has a dismal prognosis and limited therapeutic options. Here, we investigate the nuclear export protein XPO1 as a critical driver of ATL proliferation and a promising therapeutic target. We used a multi-level approach, combining systems biology analysis of three independent ATL patient cohorts with in vitro functional validation. Our systems analysis revealed that XPO1 expression is significantly elevated and differentially spliced in acute ATL, and is central to a pro-proliferative gene module, positively correlated with both the ATL transcriptional signature and tumor clonality. This ex vivo link was confirmed in vivo in four unique long-term surviving patients, for which successful therapy with IFN-α+AZT led to a concurrent decrease in XPO1 and key proliferation marker PCNA . Furthermore, we demonstrated that pharmacological inhibition of XPO1 with the clinical-stage compound Selinexor (KPT-330) and a related SINE compound, KPT-185, decreased proliferation and induced apoptosis in HTLV-1-transformed cells. Mechanistically, XPO1 inhibition exerted its anti-tumor effect by dismantling the pro-survival NF-κB pathway. Our combined findings establish XPO1 as a relevant therapeutic target in ATL and suggest its possible use as a biomarker for therapeutic response.

This paper describes ultrasound synthesis, structural characterization and biological activity of new derivatives of 2-arylbenzimidazole 12–27 and 1,2,3-triazole derivatives of 2-arylbenzimidazole 28–33.

Overexpression of exportin 1 (XPO1/CRM1) in cancer cells mislocalizes numerous cancer-related nuclear export cargoes. Covalent selective inhibitors of nuclear export (SINEs), including the cancer drug selinexor, restore proper nuclear localization by blocking XPO1-cargo interaction. These inhibitors also induce XPO1 degradation through the Cullin-RING E3 ligase (CRL) substrate receptor ASB8. Here we present cryo-electron microscopy structures revealing ASB8 binding to a cryptic XPO1 site that is exposed upon SINE conjugation. Unlike typical molecular glue degraders that directly bridge CRLs and substrates, SINEs bind XPO1 independently of ASB8, triggering an allosteric mechanism that enables high-affinity ASB8 recruitment, leading to XPO1 ubiquitination and degradation. ASB8-mediated degradation is also triggered by the endogenous itaconate derivative 4-octyl itaconate, suggesting that synthetic XPO1 inhibitors exploit a native cellular mechanism. This allosteric XPO1 degradation mechanism expands known modes of targeted protein degradation beyond molecular glue degraders and proteolysis-targeting chimeras of CRL4.

The nuclear export receptor exportin 1 (XPO1/CRM1) is often overexpressed in cancer cells, leading to the mislocalization of numerous cancer-related protein cargoes 1,2 . Selinexor, a covalent XPO1 inhibitor, and other Selective Inhibitor of Nuclear Export (SINEs) restore proper nuclear localization by blocking XPO1-cargo binding 2-7 . SINEs also induce XPO1 degradation via the Cullin-RING E3 ubiquitin ligase (CRL) substrate receptor ASB8 7 . Here we elucidate the mechanism underlying the high-affinity engagement of CRL5 ASB8 with SINE-conjugated XPO1. Cryogenic electron microscopy (cryoEM) structures reveal that ASB8 binds to a cryptic site on XPO1, which becomes accessible only upon SINE conjugation. While molecular glue degraders typically interact with both CRL and the substrate 8-10 , SINEs bind to XPO1 without requiring interaction with ASB8 for efficient XPO1 degradation. Instead, an allosteric mechanism facilitates high affinity XPO1-ASB8 interaction, leading to XPO1 ubiquitination and degradation. ASB8-mediated degradation is also observed upon treatment of the endogenous itaconate derivate 4-octyl itaconate, which suggests a native mechanism that is inadvertently exploited by synthesized XPO1 inhibitors. This allosteric XPO1 degradation mechanism of SINE compounds expands the known modes of targeted protein degradation beyond the well-characterized molecular glue degraders and proteolysis targeting chimeras of CRL4.

To evaluate the effect of amination on biofilm inhibition against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, representative compounds of two previously described 5-aryl-2-aminoimidazole (5-Ar-2-AI) classes were aminated by installing an amino group at the end of the substituted n-alkyl chain. Amination led to an improvement in activity for one of the two classes, the 2N-substituted 5-Ar-2-AI class. Based on these findings, a more extensive library of 2N-substituted-aminated 5-Ar-2-AIs was synthesized having different n-alkyl and halogen substitutions on the 2N-position and the 4(5)-phenyl ring, respectively. Compounds were evaluated for their biofilm inhibitory activity against E. coli, P. aeruginosa, S. aureus, Staphylococcus epidermidis and MRSA. Additionally, their toxicity was tested on eight continuous cell lines, peripheral blood mononuclear cells and Caenorhabditis elegans, along with their genotoxicity on Capan-1. Halogenation and elongation of the n-alkyl substituent showed a positive effect on biofilm inhibitory activity, but also increased toxicity. Compromising between activity and toxicity, a non-halogenated 2N-substituted-aminated 5-Ar-2-AI compound with an intermediate n-heptyl substitution demonstrated promising broad-spectrum biofilm inhibition, making it a suitable candidate for further research in anti-infectious medical applications.