Polo-like kinase 2 (PLK2), a serine/threonine kinase involved in cell cycle regulation, has emerged as a promising therapeutic target in cancer due to its role in tumor cell proliferation and survival. In this study, we report the design and synthesis of novel PLK2 inhibitors, featuring pyrazolo[3,4-d]pyrimidine derivatives. Among them, compounds 8 and 11 exhibited potent PLK2 inhibitory activity, with IC50 values of 0.36 μM and 0.78 μM, respectively (ON1231320, IC50 = 0.10 μM). In colorectal cancer cell lines SW480 and HT29, compounds 8 and 11 suppressed cell proliferation in a dose-dependent manner, induced apoptosis, caused cell cycle arrest, and inhibited anchorage-independent growth. Notably, compound 11 showed significant in vivo tumor growth efficacy in a xenograft mouse model (TGI = 69.37%), markedly superior to ON1231320 (TGI = 8.36%) with favorable pharmacokinetic parameters. These findings establish pyrazolo[3,4-d]pyrimidine derivatives as promising PLK2 inhibitors with strong therapeutic potential for colorectal cancer.
Steroidal scaffolds are central to drug discovery due to their unique three-dimensional frameworks and biological relevance. The fusion or conjugation of these cores with five-membered heterocycles has emerged as a promising strategy to enhance pharmacological profiles, particularly in anticancer and anti-inflammatory research. This review focuses on the design, synthesis, and biological evaluation of steroid—heterocycle hybrids incorporating pyrrole, pyrazole, imidazole, isoxazole, oxazole, oxadiazole, thiazole and thiadiazole moieties. Compounds are categorized based on their linkage type: steroids with fused heterocyclic rings, directly conjugated systems, flexible spacer-linked hybrids and shared atomic frameworks (spirosteroids). Structure–Activity Relationships (SAR) are discussed to elucidate the impact of different heterocyclic systems on bioactivity. By systematically analyzing over ninety recent studies, this review provides a comprehensive reference for medicinal chemists interested in optimizing steroid-based drug candidates through strategic heterocycle incorporation.
β2-Adrenergic receptor (β2-AR) agonists, as classic bronchodilators, serve as the cornerstone for asthma treatment. Herein, we designed and synthesized a series of derivatives based on the 5-hydroxy-4H-benzo[1,4]oxazin-3-one scaffold. Based on a comprehensive evaluation of four core indicators, including cAMP accumulation assays in HEK293 cells overexpressing human β2-AR or β1-AR, guinea pig tracheal strip assays, and in vitro cytotoxicity, compound C3 exhibited the best overall performance (β2-AR EC50 = 7 pM, β2/β1 selectivity > 97-fold; isolated tracheal relaxation Emax = 136.88, pD2 = 8.32; human bronchial epithelial cell BEAS-2B CC50 = 50.07 μM) and was selected as the candidate molecule. In a mouse asthma model, C3 administered at 200 μg/kg/day (458.5 nmol/kg/day) markedly suppressed inflammatory cell activity and improved lung function, showing anti-asthmatic efficacy comparable to that of salmeterol at 300 μg/kg/day (721.7 nmol/kg/day). In conclusion, C3 is a β2-AR agonist with potential application value, holding promise for the treatment of asthma.
Acute myeloid leukemia (AML) driven by FLT3-ITD mutations remains a therapeutic challenge with limited treatment options. Herein, we report the design, synthesis, and biological evaluation of a series of 4-(2-fluorophenoxy)pyridine derivatives featuring an imidazolidinone carboxamide linker as potent FLT3-ITD inhibitors. Systematic structure-activity relationship exploration identified compound 18p as the optimal candidate, which displayed exceptional enzymatic potency against FLT3-ITD (IC50 = 1.1 nM) and single-digit nanomolar antiproliferative activity against FLT3-ITD driven AML cell lines (BaF3-FLT3-ITD IC50 = 5.7 nM; MOLM-13 IC50 = 1.6 nM). Compound 18p demonstrated a marked selectivity profile, discriminating FLT3-ITD from FLT3-WT and sparing normal PBMCs and a broad panel of solid tumor cells. Kinome profiling revealed that 18p maintained high selectivity over c-Kit, CDKs, FGFRs, and the majority of 60 tested kinases, with PDGFRβ identified as the principal off-target liability. Mechanistically, 18p suppressed FLT3 autophosphorylation and downstream STAT5, AKT, and ERK signaling more effectively than gilteritinib at equimolar concentrations, and induced potent G1-phase arrest and apoptosis in MOLM-13 cells. In the MV4-11 xenograft model, oral administration of 18p at 10 mg/kg achieved 80% tumor growth inhibition, comparable to gilteritinib at 2.5 mg/kg, with concomitant suppression of Ki67 and p-STAT5 and induction of cleaved caspase-3 and γH2AX in tumor tissues. Histopathological examination of major organs confirmed an absence of overt toxicity. These findings position 18p as a promising FLT3-ITD inhibitor and provide valuable insights for further development of mutation-selective AML therapeutics.
As the key executioner protein of pyroptosis, GSDMD represents a promising yet underexplored therapeutic target for inflammatory diseases. In this study, we explored a PROTAC-based degradation approach targeting GSDMD for the treatment of pyroptosis-driven inflammatory conditions. Through screening of our in-house compound library, we identified a high-affinity GSDMD binder, PGC (KD = 9.42 nM). Through rational design of linkers and systematic optimization of the E3 ligase attachment site, we constructed a series of PROTACs and identified PGC-01 as a CRBN-recruiting and effective GSDMD degrader (DC50 = 3.32 μM, Dmax = 85%). Functionally, PGC-01 concentration-dependently suppressed nigericin-induced macrophage pore formation, cell death, and IL-1β release. In vivo, rectal administration of PGC-01 dose-dependently alleviated clinical symptoms and pathological damage in a DSS-induced murine colitis model. Collectively, this study provides critical proof-of-concept that targeted degradation of GSDMD is a viable therapeutic strategy and positions PGC-01 as a promising lead compound for the treatment of GSDMD-driven inflammatory diseases.
Animal-derived low-molecular-weight heparins (LMWHs) are essential anticoagulants but are associated with supply chain vulnerabilities and contamination risks, alongside incomplete protamine reversibility in clinical practice. Herein, we report the precision chemoenzymatic tailoring of bioengineered LMWHs from Escherichia coli K5 capsular polysaccharide (heparosan) to achieve protamine-reversible anticoagulation. Through the integration of chemical N-deacetylation/N-sulfation, precisely regulated C5-epimerization/2-O-sulfation, controlled β-eliminative depolymerization, and sequential enzymatic 6-O/3-O-sulfation, the molecular weight distribution and specific sulfation patterns were rationally modulated. The representative bioengineered product, L3S-2, exhibited potent anti-factor Xa activity, an optimized anti-factor Xa/anti-factor IIa ratio, and pharmacokinetic properties comparable to enoxaparin following subcutaneous administration. Crucially, L3S-2 demonstrated significantly improved protamine reversibility both in vitro and in vivo compared to commercial enoxaparin. In rat thrombosis models, L3S-2 potently inhibited venous and arterial thrombus formation, demonstrating efficacy comparable to enoxaparin. These findings establish a rational design framework for bioengineered anticoagulants, demonstrating that optimizing multivalent electrostatic interactions with protamine via tailored sulfation and molecular weight yields highly reversible agents with optimized therapeutic indices.
Imidazole and benzimidazole scaffolds belong to heterocyclic scaffolds and are privileged substances in medicinal chemistry. These two substances are related to pharmacology. The reason for this is that they have unique physical and chemical properties and can form hydrogen bonds in many ways, and they have outstanding performance in bioisostere. The U.S. Food and Drug Administration (FDA) has been able to regulate a series of pharmaceutical agents, and the clinical significance of these heterocyclic compounds is self-evident, which can be used in many fields such as cardiology, gastroenterology, oncology and neurology. This review analyzes the development of FDA-approved drugs from 2013 to 2025, and focuses on the synthesis of such drugs and the performance of such drugs through the analysis of the characteristics of such drugs and the collection of pharmacological data, in order to provide reference for chemical researchers to develop next-generation small molecule drugs.
A novel series of 5,6-diphenyl-1,2,4-triazine-3-yl-thioacetamide-chalcone hybrids (9a-n) was designed, synthesized, and evaluated for their antidiabetic potential. All derivatives exhibited potent in vitro α-glucosidase inhibitory activity (IC50 = 0.2-112 μM) compared with acarbose (IC50 = 750.0 μM). The most potent compound, 9b (IC50 = 0.2 μM), acted as a competitive inhibitor with a Ki value of 200 nM and demonstrated significant glucose-lowering activity in a zebrafish model. In addition, compound 9b effectively inhibited bovine serum albumin (BSA) glycation relative to aminoguanidine. Molecular docking and molecular dynamics revealed stable binding of compound 9b within the α-glucosidase active site, with a binding energy of -9.2 kcal/mol, compared with -4.04 kcal/mol for acarbose. According to the in silico ADMET analysis, compound 9b showed oral bioavailability comparable to acarbose, together with improved drug-like properties. Overall, these findings identify compound 9b as a promising lead α-glucosidase inhibitor with potent in vitro and in vivo antihyperglycemic activity, warranting further investigation for the treatment of type 2 diabetes.
Hepatocellular carcinoma is a malignant tumor that ranks sixth in incidence and third in mortality globally. In this study, based on the principles of chemical splicing and prodrug synthesis strategies, a total of 26 new derivatives, including 17 cinnamic acid derivatives, 8 quinoline derivatives, and 1 triazole derivative, were designed and synthesized using terrein (1), isolated from the endophytic fungus Aspergillus terreus of Sphagneticola trilobata as the parent compound. Among these, the IC50 values for the proliferation-inhibitory effects of the cinnamic acid derivative 1i and the quinoline derivative 2a on liver cancer cells Hep G2 were 0.8 and 4.6 μM, respectively, which were 120 and 21-fold stronger than those of 1. In addition, 1i and 2a exhibited proliferation inhibition rates against Hep G2 cells were observed to be lower by factors of 14.4 and 9.65, respectively, compared to those against AML-12 cells, demonstrating that moderate selectivity and a certain therapeutic window are exhibited by these compounds. Molecular mechanism studies have shown that both 1i and 2a could induce apoptosis in Hep G2 cells by inhibiting the PI3K/Akt signaling pathway, arresting the cell cycle, and suppressing cell proliferation and migration. The difference is that 1i arrested the cell cycle in the S phase, while 2a arrested it in the G0/G1 phase. Further transcriptomic analysis, combined with molecular docking and isothermal titration calorimetry results, indicated that the likely target of 1i was NCF2, while the target of 2a was WNT9A. In vivo studies further confirmed that 1i demonstrated superior anti-tumor activity and safety compared to positive control Sorafenib. Overall, the findings of this study indicate that derivatives 1i and 2a are highly promising candidate drugs for the treatment of hepatocellular carcinoma.
Hepatocellular carcinoma (HCC) remains a significant clinical challenge, and targeting the dual phosphorylation of signal transducer and activator of transcription 3 (STAT3) has emerged as a promising strategy for HCC treatment. In this study, 25 novel β-carboline-benzo[b]thiophene 1,1-dioxide hybrids were designed and synthesized via structural modification of the β-carboline scaffold. Among them, compound 18 exhibited the most potent antiproliferative activity against Huh-7 cells in vitro, with an IC50 value of 1.30 ± 0.05 μM, and significantly suppressed colony formation and cell migration. Mechanistic investigations demonstrated that compound 18 directly bound to STAT3 protein with a KD value of 5.63 μM, as determined by surface plasmon resonance (SPR), and markedly inhibited its phosphorylation at both Tyr705 and Ser727 residues, consequently blocking its nuclear translocation. In addition, compound 18 impaired mitochondrial function by reducing ATP production and elevating reactive oxygen species (ROS) levels. In a Huh-7 xenograft mouse model, compound 18 administered at 7.5 mg/kg achieved a tumor inhibition rate of 55.08%. Collectively, these results indicate compound 18 as a promising STAT3 dual phosphorylation inhibitor for HCC treatment.
Artificial intelligence (AI) is accelerating antimicrobial peptide (AMP) discovery, but prediction-centered workflows often overlook dataset redundancy, peptide synthesizability, and experimental anti-infective translation. Here, we developed a redundancy-aware AI-guided peptide discovery workflow integrating redundancy-controlled dataset construction, model interpretation, candidate screening, synthesis-linked experimental validation, and evaluation in an infected-wound model. A redundancy-retention (RR) dataset of 1861 peptides with E. coli MIC annotations was compared with CD-HIT-filtered CD60-CD90 datasets containing 439-1061 sequences. Redundancy control reshaped activity-density distributions, SHAP-derived feature dependence, and virtual-screening stringency. Screening 2.1 million random 13-mer peptides yielded 1763, 189, 157, 141, and 20 candidates from CD60, CD70, CD80, CD90, and RR workflows, respectively. Experimental synthesis and MIC testing showed that the RR-derived group had a higher mean crude yield and a higher hit rate against E. coli than the CD90-derived group (60% vs 20%; MIC ≤16 μM). The lead peptide A36 showed broad activity against the tested Gram-negative bacteria, inhibited drug-resistant clinical A. baumannii isolates, displayed low hemolysis and cytotoxicity, retained substantial integrity in serum and antibacterial activity after protease exposure, disrupted bacterial membranes, and reduced bacterial burden while promoting wound closure in an A. baumannii-infected wound model. These findings identify redundancy control as a practical factor influencing candidate selection, synthetic accessibility, and experimental hit recovery in AI-guided AMP discovery.
This review highlights the recent emerging therapeutic potential of quinoline-based scaffolds in anticancer drug discovery. A systematic and integrative review methodology was adopted, emphasising recent literature on synthetic strategies, structure-activity relationship (SAR) trends, mechanistic insights and in vitro/in vivo evaluations of quinoline derivatives. Modern synthetic approaches have enabled the efficient construction of structurally diverse quinoline hybrids with enhanced pharmacological profiles. Biological investigations reveal that several quinoline hybrids exhibit potent anticancer activity in low micromolar to submicromolar ranges. Additionally, exceeding the efficacy of standard drugs while demonstrating enhanced selectivity towards cancer cells. Mechanistically, these compounds act through multi-target modulation, induction of apoptosis, mitochondrial dysfunction and cell cycle arrest. SAR analyses indicated that strategic substitutions on the quinoline core and hybridisation with bioactive compounds enhance target binding and efficacy. Furthermore, in silico approaches, including molecular docking and ADME profiling, provide critical support for experimental findings and facilitate rational lead optimisation. Despite promising outcomes, challenges related to drug resistance, toxicity and pharmacokinetics persist. These limitations may be addressed through continuous advancement in the design and optimisation of anticancer-active molecular frameworks. Overall, quinoline hybrids represent a versatile and promising scaffold for the development of next-generation anticancer agents.
Aurora A kinase overexpression has been implicated in ovarian cancer progression, highlighting its potential as a therapeutic target. In this study, we performed structure-based virtual screening of our proprietary natural product database, identifying hinokiflavone (HNK) as a novel Aurora A inhibitor. Kinase profiling assays revealed that HNK exhibits multi-target inhibitory activity, with preferential potency against Aurora A and B. We developed the first efficient total synthesis of HNK derivatives featuring a key Chan-Lam coupling reaction. Based on the different positions of methoxy and hydroxyl groups in the structure of HNK and its derivatives, we also compared their molecular docking simulation and molecular dynamics simulation, and found that as the number of hydroxyl groups increased, the activity of inhibiting Aurora A gradually increased. The retention of hydroxyl groups at specific positions plays a crucial role in the activity of HNK. The aforementioned research provides a preliminary theoretical foundation for a subsequent structural modification.
