Search PubMedSearch

SEARCH · Search PubMed

Results for “structure-activity relationship”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

ToxiVerse: chemical bioprofiling, toxicity data sharing and customizable predictive modeling.

MOTIVATION: Chemical toxicity assessment is critical for drug development and environmental safety. Computational models have emerged as a promising alternative to animal testing and now play a significant role in efficiently evaluating new chemicals. To address the urgent need for user-friendly machine learning tools in computational toxicology, we developed ToxiVerse, a public web-based platform. RESULTS: ToxiVerse provides automatic chemical bioprofiling, curated toxicity datasets, and a predictive modeling interface designed for researchers who lack programming expertise. The platform comprises three integrated modules: (i) Bioprofiler, which provides chemical descriptors by combining chemical-bioactivity data from PubChem assays with a machine learning-based data gap-filling procedure; (ii) Database, which hosts ∼50 000 curated chemicals covering diverse toxicity endpoints; and (iii) Cheminformatics, which enables dataset upload, chemical curation, and automatic generation of quantitative structure-activity relationship models for toxicity prediction. AVAILABILITY: The tool is accessible at www.toxiverse.com, and source code is available at https://github.com/zhu-research-group/toxiverse.

Quantitative Structure-Activity Relationship

Identification of a Nonribosomal Peptide Analog With Activity Against Multiple Gram-Positive Bacteria via a Synthetic Bioinformatic Natural Product Discovery Approach.

Nonribosomal peptide (NRP) antibiotics exhibit potent biological activities and are broadly used in clinical therapy. Because most microorganisms are difficult to culture and many antibiotic biosynthetic genes are silent, traditional activity tracking approaches face major limitations in the discovery of novel NRPs. Here, based on a synthetic bioinformatic natural product (syn-BNP) discovery approach that integrates bioinformatics and chemical synthesis, a novel nonribosomal peptide synthetase (NRPS) gene cluster from the genome of Rhodococcus erythropolis D-1 was mined. A putative NRP scaffold synthesized by the NRPS encoded by this cluster was predicted. Through chemical synthesis and four rounds of structure-activity relationship (SAR) studies, 37 NRP analogs were ultimately generated. Among these analogs, ZURJC28 shows activity against multiple Gram-positive bacteria, including two drug-resistant strains. Mechanistic studies and metabolomics analyses revealed that ZURJC28 exerts membrane-disruptive activity associated with interaction with phosphatidylglycerol (PG)-enriched Gram-positive membranes, leading to membrane damage and widespread metabolic dysregulation. ZURJC28 also shows low cytotoxicity and low hemolytic activity, suggesting its preliminary in vitro safety profile.

Gram-Positive Bacteria

Targeting SIRT6: the design and therapeutic implications of activators and inhibitors.

Sirtuin 6 (SIRT6) is an NAD+-dependent deacylase that maintains genomic stability, regulates metabolism, and influences aging, making it an attractive but challenging therapeutic target. Pharmacological modulation of SIRT6 holds promise for cancer and metabolic disorders, yet its context-dependent functions demand precise intervention strategies. Potent, selective, and drug-like chemical probes are therefore essential to dissect SIRT6 biology and to validate its therapeutic potential. This review critically evaluates recent medicinal chemistry advances in SIRT6 modulation. We focus on structure-guided design strategies and structure-activity relationships (SAR) that have transformed initial hits into optimized leads for both activators and inhibitors, highlighting the remaining challenges in achieving isoform selectivity and drug-like properties.

Sirtuins

Chalcone-indole hybrid scaffolds as promising anticancer drug candidates: a mini-review.

Cancer treatment is hampered by severe systemic side effects, poor tumor selectivity, and multidrug resistance (MDR). Molecular hybridization integrates chalcone and indole, two privileged antitumor pharmacophores, into one scaffold to generate chalcone-indole hybrids that synergistically enhance antitumor potency, improve tumor targeting, and reverse MDR. This mini-review analyzes literature from 2020 to 2026 on chalcone-indole anticancer hybrids. Based on structural modification patterns, the reported hybrids are categorized into four subgroups: simple substituted, α/β-position modified, N-1 fatty acid-substituted, and multi-pharmacophore fused hybrids. For each category, we summarize structure-activity relationships (SARs), antiproliferative activity, selective toxicity, molecular mechanisms, and in vivo xenograft performance. Most lead compounds exert tumor-suppressive effects via tubulin polymerization inhibition, G2/M cell cycle arrest, ROS overaccumulation, and mitochondrial-dependent apoptosis. Representative hybrids 10a, 12a, 21a, and 25a exhibit remarkable efficacy against drug-resistant colorectal, lung, and breast tumors with favorable in vivo safety. We highlight the application potential of different subtypes for specific malignancies, including α/β-modified analogues for resistant colorectal cancer, N-1 fatty acid-platinum conjugates for platinum-resistant lung cancer, NLRP3 inhibitor 7a for oral cancer, and multi-pharmacophore fused derivatives for broad-spectrum activity. Current bottlenecks limiting clinical transformation are discussed. This review provides structural design rules for developing novel chalcone-indole targeted anticancer agents.

Humans

Recent advances in the chemical synthesis of Glycosaminoglycans.

Glycosaminoglycans (GAGs) are complex carbohydrates ubiquitously expressed on cell surfaces and within the extracellular matrix, where they regulate essential biological processes through sequence- and sulfation-dependent interactions. Major GAG classes, including heparan sulfate (HS), chondroitin sulfate (CS), dermatan sulfate (DS), keratan sulfate (KS), and hyaluronic acid (HA), exhibit diverse sulfation patterns that encode specific molecular recognition events. Deciphering their structure-activity relationships has been hindered by intrinsic heterogeneity and limited access to well-defined materials. This review focuses on the recent advances in the chemical synthesis of GAGs, highlighting strategies that enable precise control over GAG structure and sulfation patterns. Recent innovations in protecting group design, stereoselective glycosylation, and automated assembly have significantly improved synthetic efficiency, facilitating the construction of increasingly complex and biologically relevant structures and advancing the rational design of GAG-based tools and therapeutics.

Glycosaminoglycans

Genome mining and metabolomics unveil new napyradiomycin antibiotics from Streptomyces sp. 0H2M.

Napyradiomycins are a family of meroterpenoid natural products known for their promising antibiotic activities. In this study, four new napyradiomycins derivatives were identified, SF2415B4 (1), SF2415B5 (2), SF2415B6 (3), and SF2415B7 (4) from Streptomyces sp. 0H2M, alongside a known molecule, A80915A (5) through the synergy between genome mining and metabolomics analysis. Their structures were elucidated through a combination of spectroscopic and spectrometric analyses, including HRMS-ESI, NMR, and DP4+. Genome sequencing identified a putative biosynthetic gene cluster, and subsequent analyses revealed a distinct biosynthetic pathway with an unprecedented tailoring mechanism mediated by novel hydroxylases and halogenases. Biological assays demonstrated significant activity against Bacillus subtilis, Bacillus cereus and methicillin-resistant Staphylococcus aureus due to perturbation of cell membrane integrity, and minimum inhibitory concentration (MIC) values ranged from 0.24 to 30.7 μM. Additionally, in vitro cytotoxicity experiments indicated that compounds 2-5 very mildly inhibited the viability of human non-small cell lung cancer (NSCLC) cell line A549 in a concentration-dependent manner, with IC50 values of 16.7, 39.1, 65.0, and 32.8 μM, respectively. Moreover, they were shown to induce apoptosis and autophagy in A549 cells, evidenced by increased levels of cleaved PARP, decreased expression of anti-apoptotic proteins (Bcl-2, Bcl-xL, and Survivin), and accumulation of LC3-II. These findings offer new insights into the natural product chemistry in Streptomyces and the pharmacology of napyradiomycin class antibiotics.

Streptomyces

Dictamnine alleviates oxidative stress in rheumatoid arthritis via modulation of the NR1D1-Keap1/Nrf2/ARE axis.

Rheumatoid arthritis (RA) is a persistent systemic disorder of autoimmune origin, with its core pathological manifestation being inflammation of the synovial tissue. The excessive growth of fibroblast-like synoviocytes (FLS) represents a critical pathological mechanism in RA, actively driving the advancement of the condition. Dictamnus dasycarpus Turcz. (D. dasycarpus) exhibits prominent anti-inflammatory effects and shows favorable therapeutic efficacy against RA. Dictamnine (Dic) is a major active component of D. dasycarpus, however, its therapeutic effectiveness and underlying mechanisms in RA have yet to be fully elucidated. This study investigated the effect of Dic on synovial hyperplasia in RA and elucidated the underlying mechanisms. Using a TNF-α-induced human fibroblast-like synoviocyte (HFLS-RA) model and a collagen-induced arthritis (CIA) mouse model, Dic was found to effectively inhibit synovial cell proliferation and pathological hyperplasia. Proteomics analysis was employed to clarify its potential mechanism in ameliorating the disease, and the findings were further validated through hematoxylin and eosin (H&E) staining, immunofluorescence (IF), ROS detection, JC-1 staining, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) analysis, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB). The results suggested that the anti-RA activity of Dic is associated with its interaction with the nuclear receptor NR1D1. Moreover, the NR1D1 antagonist SR8278 reversed Dic's effects on Nrf2 and cytoprotection, confirming that Dic functions through NR1D1. This activation consequently influences the Keap1/Nrf2/ARE cascade, leading to decreased intracellular reactive oxygen species (ROS) accumulation and an improvement in compromised mitochondrial membrane potential. siRNA knockdown experiments further confirmed that NR1D1 is a target of Dic and regulates the downstream Keap1/Nrf2/HO-1 signaling pathway, through which Dic ameliorates RA both in vitro and in vivo by upregulating NR1D1 expression to activate the Keap1/Nrf2/ARE antioxidant pathway, thereby mitigating oxidative stress, inhibiting synovial cell proliferation, and ultimately alleviating pathological synovial hyperplasia.

Arthritis, Rheumatoid

Discovery of acridone analogs as novel entry inhibitors targeting e protein of dengue virus.

The envelope (E) protein of the Dengue virus (DENV) is critical for virion attachment and membrane fusion with the host cell, as well as the release of the viral RNA genome into the cytoplasm. In this study, we describe the design, synthesis, and biological evaluation of novel viral entry inhibitors containing an acridone core. Notably, compound 13e demonstrated potent cellular antiviral activity (IC50 = 8.6 μM and selectivity index = 21.4). Compound 13e was evaluated using several methods, including time-of-addition and virus entry/binding assays, which revealed that it selectively blocked DENV2 infection by inhibiting virion attachment. Furthermore, compound 13e exhibited potent antiviral efficacy, as evidenced by viremia quantification and histopathological analysis results, without causing significant body weight loss or other toxicities. Furthermore, target engagement assay supported the role of compound 13e as an E protein binder, consistent with its function as an entry inhibitor.

Dengue Virus

Mapping the covalent cysteine interactome of Ebselen reveals high-sensitivity target engagement and redox proteome remodeling.

Ebselen is a covalent organoselenium compound with broad pharmacological activity, yet its cellular cysteine targets and downstream proteomic consequences remain incompletely defined. Here, we integrated competitive gel-based activity-based protein profiling, reactivity-dependent tandem orthogonal proteolysis-activity-based protein profiling, and TMT-based quantitative proteomics to map Ebselen-induced cysteine engagement and proteome remodeling in living cancer cells. Ebselen exhibited dose-dependent cytotoxicity and markedly perturbed intracellular thiol-redox balance, as reflected by glutathione depletion and altered reactive oxygen species-associated fluorescence readouts. Competitive gel-based profiling confirmed concentration-dependent engagement of protein cysteine residues in live cells. Quantitative rdTOP-ABPP further identified hundreds of dose-responsive cysteine sites in HeLa and HepG2 cells and revealed a preference for cysteine microenvironments enriched with basic residues. Cross-cell-line comparison highlighted CDK5 Cys53, SMU1 Cys298, and RPSA2 Cys163 as conserved covalent nodes, among which CDK5 Cys53 showed high sensitivity to Ebselen treatment, a finding validated by competitive labeling and MS-based site assignment. Global TMT proteomics revealed extensive remodeling of redox-related and cell-survival-associated pathways, including compensatory upregulation of selenoproteins such as TXNRD1 and GPX family members. Together, these results define a chemical proteomic atlas of Ebselen-cysteine interactions and provide a framework for understanding and optimizing covalent organoselenium therapeutics.

Humans

Development of metal-free one-pot sequential synthesis of carbazolyl-thiazolidinones as anti-leukemic agents with potential β-catenin/c-MYC pathway modulation: from synthesis to in vitro and in silico profiling.

Cancer remains a leading cause of mortality worldwide, necessitating the development of new, selective, and potent therapeutic agents. In this study, a novel, metal-free, one-pot sequential synthetic approach was developed for the synthesis of carbazolyl-thiazolidinone (CTZD) derivatives via the reaction of N-octylcarbazole-3-carbaldehyde with variety of aromatic and aliphatic primary and secondary amines and thioglycolic acid. This strategy efficiently yielded a diverse range of CTZD derivatives (4a-p) in moderate to high yields (20-95%). The synthesized compounds were characterized by FTIR, NMR (1H, 13C, DEPT, APT), and HRMS. Their in vitro cytotoxicity was tested on human leukemia cell lines NB4, K562 and U937 using MTT assays, where four derivatives (4e, 4i, 4j, and 4o) exhibited potent, concentration-dependent antiproliferative activity over the tested concentration range (1.25-10 μM). As c-MYC is a key regulator of cell proliferation, qRT-PCR analysis demonstrated that these four derivatives significantly downregulated c-MYC mRNA expression, with compound 4j producing the greatest reduction, suggesting a potential association with modulation of the Wnt/β-catenin pathway. DNA fragmentation analysis showed no detectable late-stage apoptosis, indicating that the observed c-MYC downregulation and antiproliferative effects were not associated with late-stage apoptotic cell death. The ADME/T analysis of all compounds showed favorable pharmacokinetic profiles with prediction of good oral absorption (HIA >92%) and no hERG I liability. Molecular docking studies demonstrated strong binding affinities of these compounds to β-catenin protein (PDB ID: 7ZRB) with compound 4i showing strongest affinity with ΔG = -8.10 kcal/mol via H-bonds with Ser473, Asn430, Arg469 and His470 amino acid residues. The developed metal-free synthesis provided a sustainable route to bioactive carbazolyl-thiazolidinones, and derivatives 4e, 4i, 4j, 4o could be promising leads for targeting Wnt/β-catenin/c-MYC signaling in leukemia.

Humans

Post-translational chemical modification of E3 ligase for efficient target protein degradation.

Targeted protein degradation (TPD) has emerged as a powerful therapeutic strategy, with proteolysis-targeting chimeras (PROTACs) leading efforts to address previously undruggable targets. However, PROTACs face challenges such as low bioavailability and poor pharmacokinetic properties which limit their biological applications. Here, we report a strategy termed post-translational chemical modification targeting chimera (PTcM-TAC), which integrates ligand-directed chemistry into the PROTAC framework to achieve sustained target protein degradation through covalent modification of E3 ligases. PTcM-TAC incorporates an electrophilic dibromophenyl benzoate warhead into the linker connecting the E3 ligase ligand and the protein-of-interest (POI) ligand, enabling selective transfer of the POI ligand onto the recruited E3 ligase while releasing the E3-binding moiety. Mechanistic studies, including LC-MS/MS peptide mapping, pull-down assays, and structural modeling, demonstrated site-selective modification of CRBN by the PTcM-TAC. The resulting ligand-labeled E3 ligase enables sustained pseudo-catalytic target recognition through a simplified binary interaction, thereby maintaining degradation activity even after compound washout. Furthermore, we successfully applied the PTcM-TAC strategy to another representative E3 ligase, von Hippel-Lindau (VHL), which exhibited substantially sustained degradation activity compared with conventional PROTACs. To our knowledge, PTcM-TAC represents the first ligand-directed chemical strategy that converts transient PROTAC-mediated ternary complex formation into binary target recognition via post-translational chemical modification of an E3 ligase. We believe that PTcM-TAC could provide a platform for next-generation targeted protein degraders to overcome the current limitation of PROTAC approach.

Ubiquitin-Protein Ligases

Discovery of novel quinazoline-containing ATR inhibitor for treatment of acute myeloid leukemia.

ATR is a core kinase in the DNA damage response pathway, primarily sensing replication pressure and double strand breaks, initiating cell cycle arrest, DNA repair, and apoptosis programs, and maintaining genomic stability. In this work, we validated that intervention in ATR function might regulate the progression of AML through bioinformatics analysis. And a series of novel ATR inhibitors based on quinazoline moiety were obtained. The promising compound C7 achieved effective enzyme level and cellular level inhibitory activities, and exhibited acceptable liver S9 stability and oral bioavailability, with no high risk of drug-drug interactions. Research on the underlying mechanism indicated that compound C7 could inhibit the development of MOLM-13 through a dual mechanism of rapidly inducing cell apoptosis and exacerbating DNA damage levels. In brief, compound C7 might be a promising candidate or lead compound for the discovery of novel ATR inhibitors and the treatment of AML.

Quinazolines

Design, synthesis and biological evaluation of hydroxybenzothiazole-linked benzothiazole/benzoxazole conjugates as potent dual α-amylase and α-glucosidase inhibitors.

The current study focuses on the synthesis and evaluation of novel Hydroxybenzothiazole-Linked Benzothiazole/Benzoxazole Conjugates to target Diabetes Mellitus (DM) by inhibiting α-amylase and α-glucosidase. Spectroscopic methods, including 1H and 13C NMR spectroscopy, were employed to confirm the structures of newly synthesized conjugates. The findings of in-vitro analysis displayed that the synthesized derivatives inhibited α-amylase and α-glucosidase enzymes with IC50 values ranging from 3.65 ± 0.20 μM to 32.15 ± 3.20 μM on α-amylase and 5.92 ± 0.80 μM to 35.60 ± 3.40 μM on α-glucosidase, in contrast to the reference drug Acarbose (α-amylase IC50 = 8.25 ± 0.80 μM; α-glucosidase IC50 = 10.75 ± 1.10 μM). Among the series 9a-9f and 10a-10f, analogs 10 f, 10b, 9b, and 9e displayed superior anti-diabetic activity compared to the reference drug Acarbose. The inhibitory activity of these conjugates can be attributed to their favorable and stable interactions with critical amino acid residues of targeted enzymes, as revealed through molecular docking analysis. ADMET predictions and drug-likeness evaluations showed favorable pharmacokinetic features, while DFT investigations revealed electronic insights related to bioactivity. Experimental outcomes and in silico support display that these potent Hydroxybenzothiazole-Linked Benzothiazole/Benzoxazole Conjugates were comparable to an existing diabetic mellitus inhibitor while conserving an acceptable safety profile, specifying potential for further therapeutic development and optimization against diabetic Mellitus.

Benzothiazoles

Inhibitory mechanism of anthocyanin B-ring substituents on advanced glycation end-product formation through bovine serum albumin binding: Insights from multispectral, molecular docking and proteomics approaches.

This study demonstrated that the inhibitory effect of anthocyanins on AGEs formation is highly dependent on the substitution pattern of the B-ring. Among the four anthocyanins, delphinidin-3-O-glucoside (D3G) exhibited the most potent antiglycation activity across BSA-fructose, MGO, and GO models with half-maximal inhibitory concentration (IC50) of 30.77, 200.29 and 269.97 μM. This superior performance was attributed to the presence of three hydroxyl groups on the B-ring, which facilitates a high-affinity, spontaneous binding interaction with BSA primarily through hydrophobic forces and hydrogen bonding. Spectroscopic and computational analyses revealed that D3G effectively stabilizes the protein scaffold, specifically recovering α-helix content and shielding critical subdomains (IB, IIA, and IIIA). Proteomics data are consistent with a protective binding mechanism, suggesting that D3G reduces the accessibility of key lysine and arginine residues to glycation-induced modifications. These findings provide a structural basis for developing D3G-rich extracts as targeted, structure-based functional ingredients to mitigate glycation-associated food quality degradation and related health issues.

Anthocyanins

Structure-Function Analysis of the Benzyloxy Moiety of the Delta-Opioid Receptor Positive Modulator BMS-986187: Identification of a Derivative with High Selectivity for the Delta-Opioid Receptor over the Mu-Opioid Receptor In Vitro and In Vivo.

Positive allosteric modulators (PAMs) of the delta-opioid receptor (DOR) enhance endogenous opioid signaling while avoiding the convulsant liability of orthosteric agonists. However, the prototypical DOR-PAM, BMS-986187, also potentiates mu-opioid receptor (MOR) signaling, raising concerns regarding respiratory depression and abuse liability. Here, we report a structure-activity study of the benzyloxy moiety of BMS-986187 to improve selectivity for DOR over MOR, while retaining DOR-PAM potency. Fifty-two new analogues and 12 previously reported ones featuring mono- and disubstitution of the benzyl ring and phenyl-heterocycle replacements were synthesized and evaluated in β-arrestin2 recruitment assays. Ortho-substituted derivatives consistently enhanced DOR-PAM potency, although often increased MOR-PAM activity. One pyridyl derivative (compound 35) retained high DOR-PAM potency and efficacy (EC50 = 0.1 μM, Emax = 91%) with no detectable MOR activity. In mice, compound 35 enhanced DOR-mediated reversal of nitroglycerin-induced hyperalgesia, an effect absent in DOR-knockout mice, without enhancing MOR-mediated antinociception, demonstrating in vivo selectivity.

Receptors, Opioid, delta

Copper-Containing Surface Engineering for Soft-Tissue Biomedical Devices: Structure-Function Relationships and Ion Release-Driven Biological Performance, A Systematic Review.

Copper and copper-based materials have gained increasing attention for the functional modification of implantable medical devices intended for prolonged soft-tissue contact, including vascular stents, catheters, and intrauterine devices. Owing to their broad-spectrum antimicrobial activity, redox reactivity, and involvement in angiogenesis and cellular signaling, copper-based systems offer significant potential for multifunctional surface engineering. However, achieving a balance between antibacterial efficacy, corrosion behavior, controlled ion release, and cytocompatibility remains a critical challenge. This PRISMA-compliant systematic review analyzes copper-containing materials and surface modification strategies for soft-tissue biomedical applications. A structured search of Scopus, Web of Science, and PubMed (2015-2025) identified 65 eligible studies. The review encompasses bulk copper-containing alloys, electrochemical and chemical surface modification techniques, physical vapor deposition approaches, and advanced hybrid systems integrating copper with polymers, hydrogels, or metal-phenolic networks. Across the reviewed literature, antibacterial performance was strongly dependent on copper concentration, microstructural distribution, and spatiotemporal ion release profiles. Moderate, well-controlled copper incorporation frequently improved antibacterial efficacy while maintaining acceptable hemocompatibility and cytocompatibility, particularly in vascular and blood-contacting devices. In contrast, excessive copper loading often accelerated corrosion and induced adverse cellular responses. Emerging multifunctional architectures demonstrated improved regulation of biological interactions, enabling simultaneous antibacterial, antithrombotic, and proendothelial effects. Overall, copper-based surface technologies represent a versatile platform for soft-tissue implant modification. Future translational progress will require precise control of copper release kinetics and comprehensive long-term in vivo validation to ensure safety and sustained therapeutic performance. From the authors' perspective, the most promising future direction involves multifunctional copper-based hybrid coatings capable of dynamically regulating ion release, host tissue integration, and antibacterial performance simultaneously. Strategies integrating hierarchical architectures, stimulus-responsive release systems, and clinically scalable fabrication methods are expected to play a key role in translating copper-containing surfaces from experimental concepts toward commercially viable soft-tissue biomedical devices.

Copper