Chalcone: A Privileged Structure in Medicinal Chemistry

Development and validation of a UV-Vis spectrophotometric method for estimation of total content of chalcone

In this study, a straightforward spectrophotometric method was developed for quantifying the total content of chalcones in a sample. The method exhibits linearity, accuracy, precision, repeatability, and enables the estimation of total chalcone content in trans-chalcone equivalents for a sample diluted in carbon tetrachloride and added to antimony pentachloride. The analytical wavelength was determined to be 390 nm. Linearity was observed within the concentration range of 0.3 to 17.6 µg/mL of trans-chalcone in CCl4, with a R2 of 0.9994 and a random dispersion of the residual concentrations. In the accuracy study, recoveries ranged from 98 to 102 %. In the inter-day precision study, the compared data showed no statistically significant differences based on p-values from Student's t-test and the two-tailed Kruskal-Wallis test. In the repeatability study, the coefficients of variation were 1.92 % and 2.08 %. Additionally, this method is specific for trans-chalcone in the presence of the flavanol (+)-catechin, the flavone luteolin, and the flavonol quercetin. The total content of chalcone was estimated for plant extracts in trans-chalcone equivalents (tCe). The total content of chalcones in these extracts ranged from non-detected up to 22 % of tCe. Therefore, this method can be used for the initial estimation of the overall chalcone content.

Network pharmacology, molecular docking and molecular dynamics simulation of chalcone scaffold-based compounds targeting breast cancer receptors

Compounds with a chalcone scaffold-based structure have demonstrated promising anticancer biological activity. However, the molecular interactions between chalcone scaffold-based compounds and breast cancer-associated proteins remain unclear. Through network pharmacology, molecular docking, and molecular dynamics (MD) simulation analyses, compounds with a chalcone scaffold-based structure were evaluated for their interaction with potential breast cancer targets. The compounds were retrieved from the ASINEX database, resulting in 575,302 compounds. A total of 342 compounds with chalcone scaffold-based structures were discovered. From the 342 compounds that was analysed, ten were chosen due to their adherence to Lipinski's rule, having an appropriate range of lipophilicity (LOGP), and topological polar surface area (TPSA), and absence of any toxicity. Based on target intersection, 50 target genes were found and subjected to protein-protein interaction (PPI), gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Four target genes were found to be involved in the breast cancer pathway. Consequently, molecular docking was utilised to analyse the molecular interactions between the compounds and four target protein receptors. Compound 211 exhibited the highest binding affinities for the epidermal growth factor receptor (EGFR), fibroblast growth factor receptor 1 (FGFR1), oestrogen receptor (ESR1), and cyclin dependent kinase 6 (CDK6) with values of -8.95 kcal/mol, -8.60 kcal/mol, -10.33 kcal/mol, and -9.90 kcal/mol, respectively. During MD simulation, compound 211 and its respective proteins were stable, compact, and had minimal flexibility. The findings provide foundations for future studies into the interaction underlying the anti-breast cancer potential of compounds with chalcone-based scaffold structures.

Regulation of adipokine and batokine secretion by dietary flavonoids, as a prospective therapeutic approach for obesity and its metabolic complications

Traditionally recognised as the energy reservoir and main site of adaptive thermogenesis, white and brown adipose tissues are complex endocrine organs regulating systemic energy metabolism via the secretion of bioactive molecules, termed "adipokines" and "batokines", respectively. Due to its significant role in regulating whole-body energy metabolism and other physiological processes, adipose tissue has been increasingly explored as a feasible therapeutic target for obesity. Flavonoids are one of the most significant plant polyphenolic compounds holding a great potential as therapeutic agents for combating obesity. However, understanding their mechanisms of action remains largely insufficient to formulate therapeutic theories. This review critically discusses scientific evidence highlighting the role of flavonoids in ameliorating obesity-related metabolic complications, including adipose tissue dysfunction, inflammation, insulin resistance, hepatic steatosis, and cardiovascular comorbidities in part by modulating the release of adipokines and batokines. Further discussion advocates for the use of therapeutics targeting these bioactive molecules as a potential avenue for developing effective treatment for obesity and its adverse metabolic diseases such as type 2 diabetes.

Antimicrobial and anti-biofilm activity of a mucoadhesive hydrogel functionalized with aminochalcone on titanium surfaces and in Galleria mellonella model: In vitro and in vivo study

Peri-implantitis associated with dental implants shares characteristics with destructive periodontal diseases. Both conditions are multifactorial and strongly correlated with the presence of microorganisms surrounding the prostheses or natural dentition. This study aimed to evaluate the antimicrobial activity and toxicity of a mucoadhesive hydrogel functionalized with aminochalcone (HAM-15) against Aggregatibacter actinomycetemcomitans, Fusobacterium periodonticum, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Candida albicans. Various experiments were conducted to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC), as well as the antibiofilm potential and toxicity in human gingival fibroblasts and a G. mellonella animal model. Infection and treatment studies were also performed in G. mellonella. The results demonstrated that both aminochalcone (AM-15) and the aminochalcone-functionalized hydrogel (HAM-15) exhibited antimicrobial activity, with MICs ranging from 7.8 to 31.2 μg/mL for the tested strains. Treatment with HAM-15 at 300 μg/mL reduced the monospecies biofilm of C. albicans and P. gingivalis by 7 log10 and 6 log10, respectively, and the mixed-species biofilm of these microorganisms by 7 log10 and 8 log10, respectively. Regarding toxicity, HAM-15 showed cytotoxic effects on human gingival fibroblasts at high concentrations, but in the G. mellonella model, survival was 70 % at a dose of 1 mg/mL. Additionally, AM-15, when administered after larval infection, protected 90 % of the animals (p < 0.05). These results suggest that AM-15 is a promising candidate for the prevention and treatment of anaerobic infections and yeasts, demonstrating significant antimicrobial efficacy and an acceptable safety profile in experimental models.

Chalcone Synthesis by Green Claisen-Schmidt Reaction in Cationic and Nonionic Micellar Media

In this paper, micellar-mediated synthesis of chalcones was explored. After optimization of the reaction conditions, the cationic surfactant CTAB and the nonionic one, Tween 80, were taken into consideration. Both surfactants were used to study the scope of Claisen-Schmidt reactants, and a wide scope on both aromatic aldehydes and methyl ketones was explored, obtaining from good to very good yields in most cases and thus demonstrating that the chalcones can be proficiently synthesized in micellar solutions with a wide functional group tolerability. Often, when one surfactant did not perform well, the other surfactant performed better, demonstrating that the use of different surfactants can constitute a good alternative to overcome reactivity problems. Besides, Tween 80 can be proposed as a good and greener alternative to CTAB in most cases. Some reactions gave low yields, showing that some specific improvements would be needed to address the low reactivity. The micellar medium was studied by NMR to search for information about the association of the Claisen-Schmidt reactants with the micelles and their locations within them. Diffusion Ordered Spectroscopy (DOSY) was applied to assess the interaction and the percentage of incorporation of reactants into the micelles.

Microwave-Assisted Synthesis of Near-Infrared Chalcone Dyes: a Systematic Approach

(E)-3-[4-(Dimethylamino)phenyl]-1-(2-hydroxyphenyl)prop-2-en-1-one is an organic dye with potential application in dye-sensitized solar cells. In order to fully investigate and characterize this molecule, many synthetic approaches were applied, including base and acid-catalyzed synthetic methodologies. NaOH, KOH, Ba(OH)2·8H2O, K2CO3, Et3N, SOCl2, HCl, HOAc, and Ac2O were utilized in different solvents and reaction conditions; however, all attempts failed to access the desired product in an efficient and productive way. A good success was achieved employing excess of piperidine, as base in refluxing ethanol. The reaction completed in 3 days; however, the product was obtained in 85% purity. In order to minimize the formation of side products, and taking in consideration a greener approach, such as shortening the extended reaction time and reducing excess production of organic wastes, the reaction was performed under controlled microwave reaction conditions. With greater success, the desired product was obtained in excellent isolated yield and high purity, in a shorter reaction time. This novel approach was then explored to investigate its scope and limitations to access other chalcone dyes.

SMILES-based QSAR and molecular docking studies of chalcone analogues as potential anti-colon cancer

QSAR modeling was applied to predict the anti-colon activity (against HT-29) of 193 chalcone derivatives using the Monte Carlo method, based on the index of ideality correlation (IIC) target function. The models were constructed using CORAL software, which employed optimal descriptors combining SMILES notation and hydrogen-suppressed molecular graphs (HSG). Among the developed models, Split #2 was identified as the best-performing model, with R2_validation = 0.90, IIC_validation = 0.81, and Q2_validation = 0.89. The mechanistic interpretation of the models, utilizing enhancing/reducing promoters, demonstrated that the models are capable of accurately predicting the pIC50 values of other chalcone derivatives with high robustness and precision. Based on these promoters, ten new compounds were selected from the ChEMBL database for pIC50 prediction, and molecular docking was performed using the protein with PDB ID:1SA0.

Oxime functionalized Chalcones: Unveiling a new class of Chalcones with potent Antiplasmodial activity against blood-stages of Plasmodium falciparum in culture

The Plasmodium falciparum parasite, which is responsible for malaria, has developed resistance to several first-line antimalarial drugs. To address this issue, researchers have been developing novel hybrid molecules that can inhibit parasite growth. In this study, a total of 38 chalcone oxime ethers, consisting of four different types, were evaluated for in vitro blood-stage antiplasmodial activity against P. falciparum (3D7) using SYBR green I assay. The four classes of oxime ethers showed promising to moderate antiplasmodial activity. At least one molecule from each class was potent, with the IC50 values of less than 5 μg/mL. Among the four classes, chalcone-chalconeoxime ethers (CCOE) were the most effective, with the IC50 values of 1.55 μg/mL and 1.4 μg/mL for CCOE-2 and CCOE-5, respectively. The most potent molecules, CKOE-13, COAE-2, CCOE-2, and CCOE-5, were tested against the chloroquine-resistant strain P. falciparum (INDO) exhibited IC50 values of less than 5 μg/mL. Notably, the most potent molecules did not induce hemolysis at concentrations up to 50 μg/mL. These findings highlight a new class of chalconeoxime ethers as potent antiplasmodial agents, warranting further exploration of their biological activities.

Feature Reviews in Medicinal Chemistry

This Special Issue of Pharmaceuticals ("Feature reviews in Medicinal Chemistry") contains a series of reviews covering a broad selection of topics in Medicinal Chemistry, which are chosen to illustrate important recent results in this fast-evolving interdisciplinary research area that aims to improve human health by developing drugs to combat diseases [...].

Synthesis, Biological Properties, In Silico ADME, Molecular Docking Studies, and FMO Analysis of Chalcone Derivatives as Promising Antioxidant and Antimicrobial Agents

A series of chalcone derivatives were synthesized and characterized using UV-vis, FT-IR, 1H NMR, and mass spectrometry, followed by the evaluation of their antimicrobial and antioxidant properties. In vitro screening against six bacterial strains (Staphylococcus aureus, Bacillus subtilis, Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, and Citrobacter freundii) and two fungal strains (Aspergillus niger and Trichoderma harzianum) revealed outstanding antibacterial activities, particularly with compound 5b, 5d, and 5e against S. aureus, and compounds 5c and 5h against B. subtilis. Notably, compounds 5f and 5g exhibited significant effects against P. aeruginosa, while compound 5b showed the highest antifungal activity against T. harzianum. All compounds demonstrated remarkable antioxidant activities, with 5h (IC50 values of 0.005 μM) and 5c (IC50 values of 0.006 μM) being the most potent, comparable to ascorbic acid (IC50 values of 0.007 μM). In silico evaluations confirmed favorable drug-likeness and pharmacokinetic properties for all analogues, adhering to both Lipinski's rule of Five and Veber's rule. Molecular docking studies of potent antibacterial compounds (5e and 5h) indicated strong binding affinities to the PBP-1b receptor in S. aureus, while DFT calculations provided valuable insights into their molecular reactivity and biological properties. Ligand-based enzymatic target predictions indicate that chalcone analogues (5a-m) show potential as inhibitors of oxidoreductases, kinases, enzymes, proteases, or ligands for family A GPCR. These findings position chalcone derivatives as promising candidates for therapeutic applications in combating bacterial infections and oxidative stress.

Medicinal Potential of Broussonetia papyrifera: Chemical Composition and Biological Activity Analysis

Broussonetia papyrifera (L.) L'Hér. ex Vent., a dioecious tree species that belongs to the Moraceae family, is a perennial plant found extensively throughout China. Its leaves are rich in essential trace elements such as copper, molybdenum, manganese, and iron, as well as various biologically active compounds, including amino acids, polysaccharides, proteins, as well as flavonoids, phenylpropanoids, and other polyphenolic compounds. These compounds exhibit significant pharmacological effects, such as antioxidant, lipid-lowering, heat-clearing, detoxifying, blood-cooling, diuretic, and immunomodulatory activities. In recent years, B. papyrifera has gained attention for its medicinal potential; however, breeding efforts, especially those aimed at increasing the flavonoid content, have lagged. This study reviews the progress in research on the active medicinal ingredients of B. papyrifera, with a focus on identification methods, classification criteria, and enrichment technologies for its medicinal components. The biosynthesis of structural genes and transcription factors in flavonoids has been investigated in B. papyrifera. The pharmacological effects of the secondary metabolites of B. papyrifera were systematically examined, aiming to offer strategies for enhancing the flavonoid content and promoting its medicinal value.

Fragment optimized chalcone derivatives targeting OmpA protein as a therapeutic approach against multidrug resistant Acinetobacter baumannii

Acinetobacter baumannii is a notorious pathogen associated with life-threatening infections, with its outer membrane protein A (OmpA) being a key contributor to its pathogenicity by targeting epithelial cell apoptosis. The study presents an in silico analysis of chalcone derivatives as potential therapeutic agents against the outer membrane protein A (OmpA) of Acinetobacter baumannii. We performed molecular docking to evaluate the binding interactions, revealing that isobavachalcone exhibited the highest binding affinity. Further fragment optimization (FOI) of isobavachalcone improved its binding energy. Additionally, ADMET (absorption, distribution, metabolism, excretion, and toxicity) analysis was conducted to assess the pharmacokinetic properties of the compounds. Antigenicity and allergenicity of the protein show that this protein is virulent and antigenic. Moreover, molecular docking was performed and the result shows that isobavachalcone showed the highest binding energy at -6.7 kcal/mol. Furthermore, for a more potent compound, fragment optimization was performed and led to a new lead compound fragment optimized isobavachalcone (FOI) which shows increased binding energy -6 kcal/mol. ADMET and toxicity analysis was performed of both the compounds isobavachalcone and FOI which revealed favorable pharmacokinetic profiles for both compounds, but toxicity analysis showed discrepancies, with the isobavachalcone exhibiting toxicity but FOI compound showing no detectable toxicity. This underscores the importance of structure optimization in drug development. Overall, chalcone derivatives show promise as antibacterial agents against A. baumannii, with computational analyses aiding in compound selection and optimization. While both isobavachalcone and its FOI showed favorable pharmacokinetics, in vivo and in vitro validation is needed to confirm their therapeutic potential.

Red-shifted optical absorption induced by donor-acceptor-donor π-extended dibenzalacetone derivatives

Chalcones demonstrate significant absorption in the near ultraviolet-visible spectrum, making them valuable for applications such as solar cells, light-emitting diodes, and nonlinear optics. This study investigates four dibenzalacetone derivatives (DBAd), DBA, DBC, DEP, and DMA, examining the impact of electron-donating and electron-withdrawing groups and conjugation elongation on their electronic structure in solvents of varying polarities. Using the Polarizable Continuum Model (PCM) and time-dependent density functional theory (TD-DFT), we characterized the excited states of these compounds. Our results reveal a consistent red-shift in the absorption spectrum, with electron-donating groups like ethoxy inducing a more pronounced red-shift than chlorine. Extending conjugation in DMA further shifted the absorption band to lower energy. Solvatochromism influenced the absorption intensities, underscoring the importance of evaluating parameters beyond λ max. Although our methodologies provided a satisfactory correlation between theoretical and experimental data, they also indicate the need for further theoretical models to accurately capture solute-solvent interactions and describe charge-separated states. The results indicated that dibenzalacetone derivatives have potential as alternative materials for development of organic solar cells.

Live cell imaging of lipid droplets: fluorescent chalcones as probes for lipophagy and lipid-mitochondria interactions

Lipid droplets are crucial organelles involved in cellular energy storage and metabolism, which is key in maintaining energy homeostasis through lipophagy. In this work, we successfully synthesized donor-acceptor chalcone derivatives (M1-M3) with improved photophysical characteristics, such as significant Stokes shifts and strong emission features. DFT and TDDFT calculations have been employed to evaluate the structure-property relationship of the chalcone derivatives. The molecules show excellent selectivity in staining lipid droplets in COS-7 cells and other cell lines. The molecule M1 was also further utilized to monitor verapamil-induced lipophagy. Using M1, we also demonstrate the link between lipid droplets and mitochondria during stress, emphasizing the significance of lipophagy in cellular energy balance and metabolism. These results not only shed light on the lipid metabolism but also have profound implications for researching and potentially treating metabolic diseases, underscoring the importance of our work in the field.

Synthesis and evaluation of the antifungal and antibiofilm potential of aminochalcones

Candida is a commensal fungus of clinical interest that commonly lives in oral cavity and intestine but can become an opportunist microrganism and cause severe infections. A serie of 10 aminochalcones were designed and synthetized to obtain compounds anti-Candida with potent and broad-spectrum activity. The most active compound J34 demonstrated excellent in vitro activity against Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata and Candida krusei with minimum inhibitory concentration between 1.9 and 7.8 µg/mL. The association of aminochalcone J34 with amphotericin B demonstrated synergistic effect against C. albicans, with Fractional Inhibiroty Concentration Index (FICI) value of 0.5. Subinhibitory concentration of J34 inhibited the C. albicans adhesion to human keratinocytes. Treatment with J34 reduced C. albicans biofilm formation, as well as acts on preformed biofilm in concentration-dependent mode. Time-kill curve demonstrated that J34 had fungicidal action after 12 h of treatment. Preliminary mechanism of action study showed J34 interacts with membrane ergosterol but does not act on fungal cell wall of C. albicans. In additon, in vivo studies using Galleria mellonella indicated low toxic effect of chalcone J34 after 72 h of treatment.

(E)-1-(3-(3-Hydroxy-4-Methoxyphenyl)-1-(3,4,5-Trimethoxyphenyl)allyl)-1H-1,2,4-Triazole and Related Compounds: Their Synthesis and Biological Evaluation as Novel Antimitotic Agents Targeting Breast Cancer

Background/Objectives: The synthesis of (E)-1-(1,3-diphenylallyl)-1H-1,2,4-triazoles and related compounds as anti-mitotic agents with activity in breast cancer was investigated. These compounds were designed as hybrids of the microtubule-targeting chalcones, indanones, and the aromatase inhibitor letrozole. Methods: A panel of 29 compounds was synthesized and examined by a preliminary screening in estrogen receptor (ER) and progesterone receptor (PR)-positive MCF-7 breast cancer cells together with cell cycle analysis and tubulin polymerization inhibition. Results: (E)-5-(3-(1H-1,2,4-triazol-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-1-en-1-yl)-2-methoxyphenol 22b was identified as a potent antiproliferative compound with an IC50 value of 0.39 mM in MCF-7 breast cancer cells, 0.77 mM in triple-negative MDA-MB-231 breast cancer cells, and 0.37 mM in leukemia HL-60 cells. In addition, compound 22b demonstrated potent activity in the sub-micromolar range against the NCI 60 cancer cell line panel including prostate, melanoma, colon, leukemia, and non-small cell lung cancers. G2/M phase cell cycle arrest and the induction of apoptosis in MCF-7 cells together with inhibition of tubulin polymerization were demonstrated. Immunofluorescence studies confirmed that compound 22b targeted tubulin in MCF-7 cells, while computational docking studies predicted binding conformations for 22b in the colchicine binding site of tubulin. Compound 22b also selectively inhibited aromatase. Conclusions: Based on the results obtained, these novel compounds are suitable candidates for further investigation as antiproliferative microtubule-targeting agents for breast cancer.

Chalcone derived bis-organosilane and its magnetic nanoparticles: Unveiling precision in selective Cu(II) ion detection and elucidating biocompatibility

The escalating concern regarding the adverse effects of metal ion toxicity on both human health and environmental ecosystems necessitates the development of efficient detection methodologies. This study presents a focused investigation on the selective and sensitive detection of Cu(II) ions employing hybrid magnetic nanoparticles derived from chalcone-based bis-organosilane. These nanoparticles exhibit a notably low detection limit in the nano-scale range, rendering the sensor highly sensitive to Copper(II) ion detection while maintaining robust anti-interference capabilities, even in the presence of diverse metal ions. Real sample analysis confirms the sensor's efficacy in detecting Cu(II) ions below WHO-prescribed levels. Computational analyses reveal molecular interactions and biological activities, including potent antibacterial and antioxidant properties, suggesting promising applications. Furthermore, the biological effectiveness of chalcone-derived bis-organosilane is investigated, unveiling notable antibacterial efficacy and also exhibiting potential as a scavenger of free radicals, indicating promising applications in both antibacterial and antioxidant domains.

Exploration of the cytotoxic and microtubule disruption potential of novel imidazo[1,5-a]pyridine-based chalcones

In continuation of our efforts to develop new anticancer compounds, a new series of imidazo[1,5-a]pyridine-chalcone derivatives was designed, synthesized, characterized, and evaluated for its cytotoxicity against five human cancer cell lines, i.e., breast (MDA-MB-231), colon (RKO), bone (Mg-63), prostate (PC-3), and liver (HepG2) cell lines, as well as a normal cell line (HEK). Among the synthesized compounds, two exhibited promising cytotoxicity against the MDA-MB-231 cell line with IC50 values of 4.23 ± 0.25 μM and 3.26 ± 0.56 μM. We also studied apoptotic induction of the compounds using annexin V-FITC/PI staining, and ROS-mediated mitochondrial damage was elucidated using DCFDA, followed by JC-1 staining. The potential activity of the compounds was further confirmed by immuno-fluorescence and molecular docking studies, which revealed the anticancer activity of active compounds through binding and microtubule disruption.

Synthesis, Characterization, and antiviral evaluation of New Chalcone-Based Imidazo[1,2-a]pyridine Derivatives: Insights from in vitro and in silico Anti-HIV studies

Given the ease of synthetic accessibility and the promising biological profile demonstrated by both imidazo[1,2-a]pyridine and Chalcone derivatives, a series of Chalcone-based imidazo[1,2-a]pyridine derivatives were synthesized and characterized using 1H NMR, 13C NMR, Mass Spectrometry and FTIR techniques. Density functional theory (DFT) was employed to investigate the structural and electronic properties, providing insights into potential reactive sites. The synthesized compounds were evaluated in vitro for their antiviral properties against human immunodeficiency virus type-1 (HIV-1) and human immunodeficiency virus type-2 (HIV-2) in MT-4 cells. Furthermore, Molecular docking studies show strong binding affinities with HIV-1 reverse transcriptase and HIV-2 protease. To further understand the dynamic behavior and stability of these interactions, molecular dynamics (MD) simulations were conducted. The MD results indicated stable binding conformations of the ligands within the active sites, with low RMSD and RMSF values throughout the simulation, confirming the robustness of these interactions. ADME predictions suggested acceptable pharmacokinetic profiles, though solubility remains a limitation for these compounds. Although the in vitro antiviral activity was limited, the combination of in vitro and in silico approaches provided valuable insights, guiding further structural optimization to improve bioavailability and enhance the therapeutic potential of these derivatives.

Understanding the binding mechanisms of hydroxy-chalcone-based 24-membered macrocyclic bis-epoxide with beta-lactoglobulin

The lipocalin carrier protein, β-lactoglobulin (β-lg), stands out as a crucial protein in the food industry, known for its ability to effectively bind with hydrophobic small molecules. However, it was unclear how β-lg interacts with macrocyclic molecules. In this research, we focused on two key aspects. First, we synthesized a 24-membered macrocycle 4d by modifying a natural product chalcone to create a macrocycle by connecting two ortho-hydroxyl groups of each phenyl ring of two chalcone units with alkyl chains. To enhance solubility, we converted the chalcone CC bonds to epoxide rings. Second, we investigated the binding ability and mechanism of binding of the compound with the β-lg. The β-lg and 4d interaction shows an isoemissive point at 382 nm with Kb = 4.64 ± 0.02 × 105 at 298 K, indicating the excellent protein binding ability of 4d. Remarkably, despite its size, 4d binds to the protein without altering its conformation, suggesting the availability of a spacious binding site on the protein where the molecule fits well. Molecular docking analysis confirmed the presence of such a site at the mouth of the calyx. Additionally, our 200 ns molecular dynamics simulation demonstrated that 4d adopts a conformation to interact with the hydrophobic amino acids of the binding site, ultimately stabilizing the protein.

Cinnamic Acid Derivatives: Recent Discoveries and Development Strategies for Alzheimer's Disease

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder that leads to cognitive decline and memory impairment. It is characterized by the accumulation of Amyloid-beta (Aβ) plaques, the abnormal phosphorylation of tau protein forming neurofibrillary tangles, and is often accompanied by neuroinflammation and oxidative stress, which contribute to neuronal loss and brain atrophy. At present, clinical anti-AD drugs are mostly single-target, improving the cognitive ability of AD patients, but failing to effectively slow down the progression of AD. Therefore, research on effective multi-target drugs for AD has become an urgent problem to address. The main derivatives of hydroxycinnamic acid, caffeic acid, and ferulic acid, are widely present in nature and have many pharmacological activities, such as antimicrobial, antioxidant, anti-inflammatory, neuroprotective, anti-Aβ deposition, and so on. The occurrence and development of AD are often accompanied by pathologies, such as oxidative stress, neuroinflammation, and Aβ deposition, suggesting that caffeic acid and ferulic acid can be used in the research on anti-AD drugs. Therefore, in this article, we have summarized the multi-target anti-AD derivatives based on caffeic acid and ferulic acid in recent years, and discussed the new design direction of cinnamic acid derivatives as backbone compounds. It is hoped that this review will provide some useful strategies for anti-AD drugs based on cinnamic acid derivatives.

Novel Aminothiazole-Chalcone Analogs: Synthesis, Evaluation Acetylcholinesterase Activity, In Silico Analysis

In this study, novel thiazole-chalcone analogs were synthesized, and their inhibitory effects on acetylcholinesterase (AChE) were examined. In vitro enzyme activity studies were conducted to calculate IC50 values, which were found to range between 2.55 and 72.78 µM (tacrine IC50 = 53.31 µM). The Ki values of the compounds showing the best inhibition (6g and 6e) were calculated and compared to those of the standard substance tacrine. All compounds reduced the AChE activity. Additionally, predictions made with SwissADME indicated that all compounds complied with Lipinski's rules and possessed good oral bioavailability properties, and the inhibitory effects of compounds 6e and 6g on AChE were evaluated using molecular docking and molecular dynamics simulations (100 ns). The results showed that compounds 6e and 6g had strong and stable interactions with AChE.

Bixa orellana (Bixaceae) seeds as a potential source of bioactive compounds for modulating postprandial hyperglycemia

BACKGROUND

α-Amylase (α-AMY) and α-glucosidase (α-GLU) inhibitors are important for controlling postprandial hyperglycemia (PHG). Bixa orellana (annatto) reported inhibitory activity against these enzymes because of its bioactive compound content. However, an understanding of its inhibitory mechanisms and metabolic profile is necessary to establish its therapeutic potential. The present study aimed to elucidate the inhibitory mechanisms of B. orellana extract (BOE) on α-AMY and α-GLU, identify and quantify its bioactive compounds using metabolomics (untargeted and targeted) analyses, and evaluate their interactions through in silico approaches.

RESULTS

BOE exhibited IC50 values of 37.75 and 47.06 mg mL-1 for α-AMY and α-GLU, respectively, indicating mixed and competitive inhibition types. Thirty-six putative compounds were identified by untargeted metabolomics, mainly fatty acids (dethiobiotin, occidentalol, palmitic acid, norbixin, among others). The most significant biosynthetic pathways included secondary metabolites (unclassified), unsaturated fatty acids, phenylpropanoids and flavonoid metabolism. Eighteen compounds were identified and quantified by the targeted analysis, such as l-phenylalanine, gallic acid, protocatechuic acid and naringenin. In silico studies highlighted xanthoangelol, norbixin, myricetin and 26-hydroxybrassinolide as key compounds with the highest binding affinities to enzyme active sites.

CONCLUSION

BOE effectively inhibited α-AMY and α-GLU, with gallic acid, naringenin, xanthoangelol, norbixin and 26-hydroxybrassinolide identified as key bioactive contributors. These findings provide molecular evidence of the inhibitory mechanisms of BOE and support its potential for PHG management and diabetes control. © 2024 Society of Chemical Industry.

Synthesis of Benzopyran-Phenylpropanoid Hybrids via Matsuda-Heck-Arylation and Allylic Oxidation

The synthesis of coumarin- and flavonoid-chalcone hybrids via Pd-catalyzed Heck-type coupling of arene diazonium salts and 8-allylcoumarins and -flavonoids is reported. The β-hydride elimination step proceeds with high regioselectivity if an OMOM-substituent is present at the position C7, adjacent to the allyl group. A selective allylic oxidation of the coupling products was accomplished using DDQ in the presence of silica to furnish the chalcones.

Licochalcone A-Inspired Chalcones: Synthesis and Their Antiproliferative Potential in Prostate Cancer Cells

Prostate cancer remains a significant global health concern, prompting ongoing exploration of novel therapeutic agents. Licochalcone A, a natural product in the chalcone family isolated from licorice root, is characterized by its enone structure and demonstrates antiproliferative activity in the micromolar range across various cell lines, including prostate cancer. Building on our prior success in enhancing curcumin's antiproliferative potency by replacing the substituted phenol with a 1-alkyl-1H-imizadol-2-yl moiety, we applied a similar approach to design a new class of licochalcone A-inspired chalcones. The synthesis of these target chalcones involved key [3,3]-sigmatropic rearrangement of aryl prenyl ethers and Claisen-Schmidt condensations, yielding three derivative series. These compounds were evaluated for antiproliferative activity in both androgen receptor (AR)-positive and AR-null prostate cancer cell models using WST-1 cell proliferation assay. Systematic evaluation of licochalcone A across four prostate cancer cell lines indicated a modest advantage over enzalutamide, an FDA-approved AR antagonist, in suppressing 22Rv1 cell proliferation. Interestingly, three ester derivatives by replacing the phenol next to the carbonyl with an alkoxide demonstrated similar antiproliferative potency to licochalcone A in both AR-positive and AR-negative prostate cancer cell lines. This suggests that the phenol moiety on licochalcone A may be a promising site for chemical manipulations to enhance anti-prostate cancer activity. Among the synthesized chalcones, nine derivatives showed improved selectivity for AR-positive LNCaP and 22RV1 cells relative to AR-negative PC-3 and DU145 cells, surpassing licochalcone A in selectivity. Additionally, the antiproliferative potency was highly dependent on the R group attached to the imidazole. Most of the derivatives showed antiproliferative potency against androgen receptor-positive LNCaP and 22Rv1 cells, comparable to that of enzalutamide and licochalcone A. These findings suggest that optimization of licochalcone A-inspired chalcones as potential anti-prostate cancer agents warrants further investigation.

Discovery of Highly Effective Antibacterial Agents Based on Chalcone-Benzisothiazolinone against Plant Pathogens

In this study, a series of novel chalcone compounds containing 1,2-benzisothiazolin-3-one were designed, synthesized, and screened for the prevention and control of plant bacterial diseases. The results showed that most of the target compounds displayed excellent antibacterial activities. Especially, F17 (2-(3-(4-cinnamoylphenoxy)propyl)benzo[d]isothiazol-3(2H)-one) exhibited remarkable efficacy against Xanthomonas oryzae pv Oryzae in vitro, with a half effective concentration (EC50) of 0.5 μg/mL, better than that of the commercial antibacterial agent thiodiazole-copper (TC, 56.1 μg/mL). Furthermore, F17 showed excellent effects against rice bacterial leaf blight in vivo, with protective and curative activities of 59.2% and 48.8% at 200 μg/mL, respectively, which were higher than those of TC (38.3% and 36.6%). Moreover, the bacteriostatic mechanism of F17 was elucidated through a series of biochemical experiments. The results indicated that F17 could inhibit the expression of multiple pathogenic factors and induce the host's resistance to disease by enhancing the activities of defense enzymes. Therefore, F17, which revealed the ability to combat plant bacterial diseases by orchestrating the control of multiple factors, might provide a new perspective for solving the problem of plant pathogen resistance. Overall, the results of this work demonstrated that chalcone compounds containing benzisothiazolinone as highly effective antibacterial candidates hold potential for the management of plant bacterial diseases.

Insights into Cancer Cell Imaging Probes Based on Chalcone Scaffolds: Theoretical and Experimental Perspectives

The research article details the synthesis of chalcone-chromone-based scaffolds via multicomponent reactions. These compounds were characterized using conventional spectroscopic methods, including NMR (1H and 13C), FT-IR, and HR-MS. Among the synthesized scaffolds, AZBNPy stood out, exhibiting exceptional DNA and protein targeting capabilities with superior binding parameters. Molecular docking studies indicated that AZBNPy has potential as a potent anticancer agent and a probe for cancer cell imaging. The findings showed that AZBNPy effectively inhibited cell proliferation and induced cell death by targeting HER-2, PARP-2, and HFR in MCF-7 cells. Additionally, in vitro fluorescence imaging studies confirmed AZBNPy's specificity for cancer cell receptors, displaying strong fluorescence in human breast cancer tissues. The clinical application of AZBNPy as an optical imaging agent holds significant promise in aiding surgeons with the precise identification and removal of cancerous tissues, potentially improving patient outcomes and survival rates.

Bioprospecting hydroxylated chalcones in in vitro model of ischemia-reoxygenation and probing NOX4 interactions via molecular docking

Ischemia/reperfusion injury (I/R) is a leading cause of acute kidney injury (AKI) in conditions like kidney transplants, cardiac surgeries, and nephrectomy, contributing to high global mortality and morbidity. This study aimed to analyze the protective effects of 2'-hydroxychalcones in treating I/R-induced AKI by targeting key pathological pathways. Considering strong antioxidant action along with other pharmacological roles of chalcone derivatives, six 2'-hydroxychalcones were synthesized via Claisen-Schmidt condensation and analyzed for their protective effects in an I/R induced AKI model using HK-2 cells. Among six 2'-hydroxychalcones, chalcone A4 significantly increased the HK-2 cells viability compared to I/R group. Chalcone A4 reduced the cell death events by reducing generation of cytoplasmic ROS and mitochondrial transmembrane potential. It also increased GSH and SOD activity while reducing TBARS levels, indicating strong antioxidant action. Scanning electron microscope images showed that chalcone A4 reversed I/R-induced morphological changes in HK-2 cells, including apoptotic blebbing and cytoplasmic fragmentation. Furthermore, in silico studies revealed interactions with NADPH oxidase 4, further supporting its protective role in I/R-induced AKI. These results showed that chalcone A4 possess potential protective action against I/R induced cellular damage possibly due to its strong antioxidant action and potential interaction with NOX4 subunit of NADPH oxidase.

Green synthesis of neuroprotective spirocyclic chalcone derivatives and their role in protecting against traumatic optic nerve injury

For clinically prevalent traumatic optic neuropathy (TON) and other retinal and optic nerve injuries lacking effective therapeutic agents, there is an urgent clinical demand for developing highly efficient and safe neuroprotective agents. Here, we have integrated naturally sourced chalcone with isatin through a catalyst-free green synthesis method, reporting a series of spirocyclic chalcone derivatives with significantly lower cytotoxicity than chalcone itself. Following in vitro cell protection assays in models of hydrogen peroxide and glutamic acid-induced damage, multiple active compounds capable of combating both forms of damage were identified. Among these, candidate compound X38 demonstrated promising neuroprotective prospects: in vitro, it attenuated glutamate-induced cell apoptosis, while in vivo, it effectively ameliorated retinal thinning and loss of optic nerve electrophysiological function induced by optic nerve injury. Preliminary mechanistic studies suggest that X38 exerts its neuroprotective effects by mitigating intracellular ROS accumulation, inhibiting JNK phosphorylation, and alleviating oxidative stress. Additionally, acute toxicity studies (intraperitoneal injection, 500 mg/kg) underscored the favorable in vivo safety profile of X38. Taken together, this study has designed a class of safe, neuroprotective spirocyclic chalcone derivatives that can be synthesized using green methods, offering an attractive candidate for treating retinal and optic nerve injuries.

Inflammaging and Immunosenescence in the Post-COVID Era: Small Molecules, Big Challenges

Aging naturally involves a decline in biological functions, often triggering a disequilibrium of physiological processes. A common outcome is the altered response exerted by the immune system to counteract infections, known as immunosenescence, which has been recognized as a primary cause, among others, of the so-called long-COVID syndrome. Moreover, the uncontrolled immunoreaction leads to a state of subacute, chronic inflammatory state known as inflammaging, responsible in turn for the chronicization of concomitant pathologies in a self-sustaining process. Anti-inflammatory and immunosuppressant drugs are the current choice for the therapy of inflammaging in post-COVID complications, with contrasting results. The increasing knowledge of the biochemical pathways of inflammaging led to disclose new small molecules-based therapies directed toward different biological targets involved in inflammation, immunological response, and oxidative stress. Herein, paying particular attention to recent clinical data and preclinical literature, we focus on the role of endocannabinoid system in inflammaging, and the promising therapeutic option represented by the CB2R agonists, the role of novel ligands of the formyl peptide receptor 2 and ultimately the potential of newly discovered monoamine oxidase (MAO) inhibitors with neuroprotective activity in the treatment of immunosenescence.

Design, synthesis, and evaluation of chalcone derivatives as xanthine oxidase inhibitors

Xanthine oxidase (XO) is an important enzyme that catalyzes the oxidation of hypoxanthine to xanthine and xanthine to uric acid in the catabolism of purines in humans. This makes XO a well-recognized target in alleviating hyperuricemia. The present study adapted a structure-based drug discovery approach to develop potent and low-toxicity XO inhibitors with the chalcone skeleton. We introduced a carboxyl group and a hydroxyl group to the B ring and modified the A ring. 35 chalcone derivatives were designed and synthesized. All the 35 derivatives exhibited higher XO inhibition activities (IC50 = 0.064-0.559 μM) compared with allopurinol (IC50 = 2.588 μM). Their high affinity was attributed to strong hydrogen bond interactions formed between the introduced carboxyl and hydroxyl groups with key amino acid residues in XO. SAR analysis disclosed that carboxyl, hydroxyl, ethyl (12c), methylamino (12h), dimethylamino (12i), indolin (13k), and indol (13l) groups played important roles in improving the whole molecules' inhibition potency against XO. ADME predictions and cytotoxicity assays suggested their pharmacokinetic characteristics and biocompatibility were desirable. Additionally, 12c exhibited a significant hypouricemic effect on potassium oxonate-induced hyperuricemia rats after orally administrated at a dose range of 10-40 mg/kg, representing a promising anti-hyperuricemia potential for further optimization and development.

(E)-2-Benzylidenecyclanones: Part XX-Reaction of Cyclic Chalcone Analogs with Cellular Thiols: Unexpected Increased Reactivity of 4-Chromanone- Compared to 1-Tetralone Analogs in Thia-Michael Reactions

In vitro relative cytotoxicity (IC50 (IIb)/IC50 (IIIb) of (E)-3-(4'-methylbenzylidene)-4-chromanone (IIIb) towards human Molt 4/C8 and CEM T-lymphocytes showed a >50-fold increase in comparison to those of the respective tetralone derivative (IIb). On the other hand, such an increase was not observed in the analogous 4-OCH3 (IIc and IIIc) derivatives. In order to study whether thiol reactivity-as a possible basis of the mechanism of action-correlates with the observed cytotoxicities, the kinetics of the non-enzyme catalyzed reactions with reduced glutathione (GSH) and N-acetylcysteine (NAC) of IIIb and IIIc were investigated. The reactivity of the compounds and the stereochemical outcome of the reactions were evaluated using high-pressure liquid chromatography-mass spectrometry (HPLC-MS). Molecular modeling calculations were performed to rationalize the unexpectedly higher thiol reactivity of the chromanones (III) compared to the carbocyclic analog tetralones (II). The results indicate the possible role of spontaneous thiol reactivity of compounds III in their recorded biological effects.

Biological effects and mechanisms of dietary chalcones: latest research progress, future research strategies, and challenges

Dietary plants are an indispensable part of the human diet, and the various natural active compounds they contain, especially polyphenols, polysaccharides, and amino acids, have always been a hot topic of research among nutritionists. As precursors to polyphenolic substances in dietary plants, chalcones are not only widely distributed but also possess a variety of biological activities due to their unique structure. However, there has not yet been a comprehensive article summarizing the biological activities and mechanisms of dietary chalcones. This review began by discussing the dietary sources and bioavailability of chalcones, providing a comprehensive description of their biological activities and mechanisms of action in antioxidation, anti-inflammation, anti-tumor, and resistance to pathogenic microbes. Additionally, based on the latest research findings, some future research strategies and challenges for dietary chalcones have been proposed, including computer-aided design and molecular docking, targeted biosynthesis and derivative design, interactions between the gut microbiota and chalcones, as well as clinical research. It is expected that this review will contribute to supplementing the scientific understanding of dietary chalcones and promoting their practical application and the development of new food products.

Labeled and Label-Free Target Identifications of Natural Products

Target identification, employing chemical proteomics, constitutes a continuous challenging endeavor in the drug development of natural products (NPs). Understanding their targets is crucial for deciphering their mechanisms and developing potential probes or drugs. Identifications fall into two main categories: labeled and label-free techniques. Labeled methods use the molecules tagged with markers such as biotin or fluorescent labels to easily detect interactions with target proteins. Thorough structure-activity relationships are essential before labeling to avoid changes in the biological activity or binding specificity. In contrast, label-free technologies identify target proteins without modifying natural products, relying on changes in the stability, thermal properties, or precipitation in the presence or absence of these products. Each approach has its advantages and disadvantages, offering a comprehensive understanding of the mechanisms and therapeutic potential of the NPs. Here, we summarize target identification techniques for natural molecules, highlight case studies of notable NPs, and explore future applications and directions.

Antibacterial activity of structurally diverse natural prenylated isobavachalcone derivatives

Isobavachalcone (IBC) is a natural prenylated flavonoid containing chalcone and prenyl chain moieties with a wide range of biological and pharmacological properties. In this work, we synthesized structurally diversified derivatives (IBC-2 to IBC-10) from the natural prenylated chalcone IBC isolated from Psoralea corylifolia and assessed their antibacterial potency against the Gram-positive and Gram-negative bacterial strains S. aureus ATCC 29213, MRSA ATCC 15187, E. coli ATCC25922 and P. aeruginosa ATCC 27853. IBC and IBC-2 exhibited a minimum inhibition concentration (MIC) of 5.0 μM against S. aureus ATCC 29213, whereas IBC-3 exhibited a broad-spectrum activity against Gram-positive and Gram-negative pathogens. Cytotoxicity assessments on the murine RAW 264.7 macrophage cell line revealed minimal to moderate cytotoxicity for IBC-2 and IBC-3 with a favorable selectivity index (>10). Time- and concentration-dependent studies further supported the bactericidal nature of the compounds, as IBC, IBC-2, and IBC-3 exhibited concentration-dependent killing of S. aureus in a time-dependent manner. Furthermore, combination studies, SEM analysis, and PI staining suggest that IBC-3's mechanism of action targets the bacteria's cytoplasmic membrane or cell wall. The bioactive compounds displayed promising drug-like characteristics and a favorable pharmacokinetic profile (ADME-Tox), indicating a projected high oral bioavailability. Structure-activity relationships (SARs) drawn from this study reveal that a prenyl chain at the A-ring and hydroxy functional groups attached to the aromatic rings of chalcone scaffolds are responsible for this antibacterial potential, which will be helpful in the future discovery and development of antibiotics from natural products to overcome the antibiotic resistance crisis.

Bis-Chalcones: Recent Reports of Their Diverse Applications in Biological and Material Sciences

Originating from the basic chalcone structure, bis-chalcones are characterized by their dual α,β-unsaturated carbonyl systems and carry a range of biological activities that include antimicrobial, antiviral, antiparasitic, antioxidant, antiproliferative, and chemical reactivities that warrant a review to cover recent progress. Thus, this review presents the significant potential demonstrated by bis-chalcones in various biological applications. For example, compounds 2.3.1 showed excellent antiparasitic activity against leishmania with good selectivity index, and compounds 2.2.1-2.2.3 showed submicromolar activity against SupT1 cells. Compound 2.6.22 stood out in its antiproliferative activity against a panel of 60 different cell lines. Compounds 2.6.4 and 2.6.9 have been shown as submicromolar noncompetitive xanthine oxidase inhibitors. We also present their recent applications in material science, for example, as photosensitizers and photoinitiators, to showcase their broader potential for innovation in both medicinal chemistry and industrial applications.

Simple cyclic chalcone dye with multiple optical functions: Piezochromism and lysosomes staining

Both artificially synthesized and naturally occurring cyclic chalcones have been widely studied for their excellent biological activities. However, research on its photophysical properties is still limited. In the present study, we designed and synthesized a small molecule fluorescent dye based on the ICT effect, using dimethylamino as the electron-donating group and carbonyl as the electron withdrawing group, and investigated its photophysical properties in depth. Although YB is a simple small molecule, it exhibits significant piezochromic properties. The fluorescence of YB can change from green to yellow through grinding. After solvent fumigation, the fluorescence reverts to green. Furthermore, YB was used successfully in the lysosomal targeting. This study expands the research on the photophysical properties of cyclic chalcone and give richness to application of cyclic chalcone compounds.

Exploring α, β-unsaturated carbonyl compounds against bacterial efflux pumps via computational approach

Antibiotic resistance has become a pressing global health crisis, with bacterial infections increasingly difficult to treat due to the emergence of multidrug resistance. This study aims to identify potential chalcone molecules that interact with two key multidrug efflux pumps, AcrB and EmrD, of Escherichia coli, using advanced computational tools. In silico ADMET (absorption, distribution, metabolism, excretion, and toxicity), drug-likeness prediction, molecular docking, and molecular dynamics simulation analyses were conducted on a ligand library comprising 100 chalcone compounds against AcrB (PDB: 4DX5) and EmrD (PDB: 2GFP). The results demonstrated that Elastichalcone A (PubChem CID 102103730) exhibited a remarkable binding affinity of -9.9 kcal/mol against AcrB, while 4'-methoxy-4-hydroxychalcone (PubChem CID 5927890) displayed a binding affinity of -9.8 kcal/mol against EmrD. Both ligands satisfied drug-likeness rules and possessed favorable pharmacokinetic profiles. Molecular dynamics simulation of the AcrB-Elastichalcone A complex remained stable over 100 ns, with minimal fluctuations in root-mean-square deviation and root-mean-square fluctuation. The screened ligand library demonstrated good drug-likeness and pharmacokinetic properties. Moreover, the MM/PB(GB)SA calculation indicated the tight binding and thermodynamic stability of the simulated protein-ligand complexes. Overall, this study highlights the potential of chalcones as promising candidates for targeting multidrug efflux pumps, offering a potential strategy to overcome antibiotic resistance. Further exploration and optimization of these compounds may lead to the development of effective therapeutics against multidrug-resistant bacterial infections.Communicated by Ramaswamy H. Sarma.

Antiparasitic activity of chalcones analogue against Trichomonas vaginalis: biochemical, molecular and in silico aspects

Trichomonas vaginalis is the etiologic agent of trichomoniasis, a worldwide distributed sexually transmitted infection (STI) that affects the genitourinary tract. Even though this disease already has a treatment in the prescription of drugs of the 5-nitroimidazole class, described low treatments adhesion, adverse side effects and cases of resistant isolates demonstrate the need for new formulations. With this in mind, chalcones emerge as a potential alternative to be tested, being compounds widely distributed in nature, easy to chemically synthesize and presenting several biological activities already reported. In this experiment, we evaluated the antiparasitic activity of 10 chalcone at a concentration of 100 μM against ATCC 30236 T. vaginalis isolates, considering negative (live trophozoites), positive (Metronidazole 100 μM) and vehicle (DMSO 0.6%) controls. Compounds 3a, 3c, 3 g and 3i showed promising results, with MICs set at 70 μM, 80 μM, 90 μM and 90 μM, respectively (p < 0,05). Cytotoxicity assays were performed on VERO and HMVII cell lines and revealed low inhibition rates at concentrations bellow 20 μM. To elucidate a possible mechanism of action for these molecules, the DPPH, ABTS and FRAP assays were performed, in which none of the four compounds presented antioxidant activity. Assays to verify ROS and lipid peroxidation in the parasite membrane were performed. None of the tested compounds identified ROS accumulation after incubation with trophozoites. 3 g molecule promoted an increase in MDA production after incubation. Results presented in this paper demonstrate the promising trichomonicidal profile, although further tests are still needed to optimize their performance and better elucidate the mechanisms of action involved.

Chalcones induce apoptosis, autophagy and reduce spreading in osteosarcoma 3D models

Osteosarcoma is the most common primary bone malignancy with a challenging prognosis marked by a high rate of metastasis. The limited success of current treatments may be partially attributed to an incomplete understanding of osteosarcoma pathophysiology and to the absence of reliable in vitro models to select the best molecules for in vivo studies. Among the natural compounds relevant for osteosarcoma treatment, Licochalcone A (Lic-A) and chalcone derivatives are particularly interesting. Here, Lic-A and selected derivatives have been evaluated for their anticancer effect on multicellular tumor spheroids from MG63 and 143B osteosarcoma cell lines. A metabolic activity assay revealed Lic-A, 1i, and 1k derivatives as the most promising candidates. To delve into their mechanism of action, caspase activity assay was conducted in 2D and 3D in vitro models. Notably, apoptosis and autophagic induction was generally observed for Lic-A and 1k. The invasion assay demonstrated that Lic-A and 1k possess the ability to mitigate the spread of osteosarcoma cells within a matrix. The effectiveness of chalcone as a natural scaffold for generating potential antiproliferative agents against osteosarcoma has been demonstrated. In particular, chalcones exert their antiproliferative activity by inducing apoptosis and autophagy, and in addition they are capable of reducing cell invasion. These findings suggest Lic-A and 1k as promising antitumor agents against osteosarcoma cells.

Bis-chalcones obtained via one-pot synthesis as the anti-neurodegenerative agents and their effect on the HT-22 cell line

In the area of research on neurodegenerative diseases, the current challenge is to search for appropriate research methods that would detect these diseases at the earliest possible stage, but also new active structures that would reduce the rate of the disease progression and minimize the intensity of their symptoms experienced by the patient. The chalcones are considered in the context of candidates for new drugs dedicated to the fight against neurodegenerative diseases. The synthesis of bis-chalcone derivatives (3a-3d), as aim molecules was performed. Their structures were established by applying 1H NMR, 13C NMR, MS, FT-IR and UV-Vis spectra. All bis-chalcones were synthesized from terephthalaldehyde and appropriate aromatic ketone as substrates in the Claisen-Schmidt condensation method and evaluated in the biological tests and in silico analysis. Compounds exerted antioxidant activity using the HORAC method (3a-3d) and decreased the activities of GPx, COX-2 (3b-3d), GR (3a-3c) and CAT (3a,3b). The high anti-neurodegenerative potential of all four bis-chalcones was observed by inhibition of acetyl- (AChE) and butyrylcholinesterase (BChE) and a positive effect on the mouse hippocampal neuronal HT-22 cell line (LDH release and PGC-1α, PPARγ and GAPDH protein expression). TD-DFT method (computing a number of descriptors associated with HOMO-LUMO electron transition: electronegativity, chemical hardness and potential, first ionization potential, electron affinity) was employed to study the spectroscopic properties. This method showed that the first excited state of compounds was consistent with their maximum absorption in the computed UV-Vis spectra, which showed good agreement with the experimental spectrum using PBE1PBE functional. Using in silico approach, interactions of bis-chalcones with selected targets (aryl hydrocarbon receptor (AhR) PAS-A Domain, ligand binding domain of human PPAR-γ, soman-aged human BChE-butyrylthiocholine complex, Torpedo californica AChE:N-piperidinopropyl-galanthamine complex and the COX-2-celecoxib complex) were characterized. Results obtained in in silico models were consistent with in vitro experiments.

A Chemical Toolbox to Unveil Synthetic Nature-Inspired Antifouling (NIAF) Compounds

The current scenario of antifouling (AF) strategies to prevent the natural process of marine biofouling is based in the use of antifouling paints containing different active ingredients, believed to be harmful to the marine environment. Compounds called booster biocides are being used with copper as an alternative to the traditionally used tributyltin (TBT); however, some of them were recently found to accumulate in coastal waters at levels that are deleterious for marine organisms. More ecological alternatives were pursued, some of them based on the marine organism mechanisms' production of specialized metabolites with AF activity. However, despite the investment in research on AF natural products and their synthetic analogues, many studies showed that natural AF alternatives do not perform as well as the traditional metal-based ones. In the search for AF agents with better performance and to understand which molecular motifs were responsible for the AF activity of natural compounds, synthetic analogues were produced and investigated for structure-AF activity relationship studies. This review is a comprehensive compilation of AF compounds synthesized in the last two decades with highlights on the data concerning their structure-activity relationship, providing a chemical toolbox for researchers to develop efficient nature-inspired AF agents.

Antimicrobial Activity of Chalcones with a Chlorine Atom and Their Glycosides

Chalcones, secondary plant metabolites, exhibit various biological properties. The introduction of a chlorine and a glucosyl substituent to the chalcone could enhance its bioactivity and bioavailability. Such compounds can be obtained through a combination of chemical and biotechnological methods. Therefore, 4-chloro-2'-hydroxychalcone and 5'-chloro-2'-hydroxychalcone were obtained by synthesis and then glycosylated in two filamentous fungi strains cultures, i.e., Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5. The main site of the glycosylation of both compounds by I. fumosorosea KCH J2 was C-2' and C-3 when the second strain was utilized. The pharmacokinetics of these compounds were predicted using chemoinformatics tools. Furthermore, antimicrobial activity tests were performed. Compounds significantly inhibited the growth of the bacteria strains Escherichia coli 10536, Staphylococcus aureus DSM 799, and yeast Candida albicans DSM 1386. Nevertheless, the bacterial strain Pseudomonas aeruginosa DSM 939 exhibited significant resistance to their effects. The growth of lactic acid bacteria strain Lactococcus acidophilus KBiMZ 01 bacteria was moderately inhibited, but strains Lactococcus rhamnosus GG and Streptococcus thermophilus KBM-1 were completely inhibited. In summary, chalcones substituted with a chlorine demonstrated greater efficacy in inhibiting the microbial strains under examination compared to 2'-hydroxychalcone, while aglycones and their glycosides exhibited similar effectiveness.

Medicinally Privileged Natural Chalcones: Abundance, Mechanisms of Action, and Clinical Trials

Chalcones have been utilized for centuries as foods and medicines across various cultures and traditions worldwide. This paper concisely overviews their biosynthesis as specialized metabolites in plants and their significance, potential, efficacy, and possibility as future medicines. This is followed by a more in-depth exploration of naturally occurring chalcones and their corresponding mechanisms of action in human bodies. Based on their mechanisms of action, chalcones exhibit many pharmacological properties, including antioxidant, anti-inflammatory, anticancer, antimalarial, antiviral, and antibacterial properties. Novel naturally occurring chalcones are also recognized as potential antidiabetic drugs, and their effect on the GLUT-4 transporter is investigated. In addition, they are examined for their anti-inflammatory effects, focusing on chalcones used for future pharmaceutical utilization. Chalcones also bind to specific receptors and toxins that prevent bacterial and viral infections. Chalcones exhibit physiological protective effects on the biological degradation of different systems, including demyelinating neurodegenerative diseases and preventing hypertension or hyperlipidemia. Chalcones that are/were in clinical trials have been included as a separate section. By revealing the many biological roles of chalcones and their impact on medicine, this paper underlines the significance of naturally occurring chalcones and their extension to patient care, providing the audience with an index of topic-relevant information.

Uncovering the Potential of Chalcone-Sulfonamide Hybrids: A Systematic Review on Their Anticancer Activity and Mechanisms of Action

Cancer is the second leading cause of death worldwide and is considered a major public health problem. Despite the significant advances in cancer research, the conventional cancer treatment approaches often lead to serious side effects that affect the quality of life of cancer patients. Thus, searching for new alternatives for cancer treatment is crucial to minimize these problems. Chalcone-sulfonamide hybrids display a range of biological activities and have been widely investigated for their anticancer potential, being considered promising molecules for cancer treatment. This systematic review aimed to summarize the information available in the literature about the anticancer potential of chalcones-sulfonamides in vitro and in vivo and their mechanisms of action. Our analysis demonstrated that chalcones-sulfonamides have relevant cytotoxic potential against different cancer cell lines in vitro, especially against the human colorectal carcinoma cell line HCT-116. These molecules have also reduced tumor growth in vivo. Some chalcones-sulfonamides had improved cytotoxicity after chemical modification and could become more selective or even more potent than reference chemotherapeutics. The mechanisms underlying these effects demonstrated that chalcones-sulfonamides may lead to cell death by different pathways, predominantly via apoptosis or necroptosis. This review may encourage researchers to advance studies with chalcones-sulfonamides, especially to elucidate their mechanisms of action, contributing to the development of new alternatives to cancer treatment.

Hydroxysafflor yellow A ameliorates alcohol-induced liver injury through PI3K/Akt and STAT3/NF-κB signaling pathways

BACKGROUND

Alcohol-associated liver disease (ALD) is a prevalent liver ailment. It has escalated into a significant public health issue, imposing substantial burdens on medical, economic, and social domains. Currently, oxidative stress, inflammation, and apoptosis are recognized as crucial culprits in improving ALD. Consequently, mitigating these issues has emerged as a promising avenue for enhancing ALD. Hydroxysafflor yellow A (HSYA) is the main ingredient in safflower, showing excellent antioxidative stress, anti-inflammatory, and anti-apoptosis traits. However, there are limited investigations into the mechanisms by which HSYA ameliorates ALD PURPOSE: We investigated whether HSYA, a significant constituent of Asteraceae safflower, exerts antioxidant stress and attenuates inflammation and anti-apoptotic effects through PI3K/Akt and STAT3/NF-κB pathways, thereby ameliorating ALD METHODS: We established two experimental models: an ethanol-induced liver damage mouse model in vivo and a HepG2 cell alcohol injury model in vitro RESULTS: The results demonstrated that HSYA effectively ameliorated liver tissue damage, reduced levels of ALT, AST, LDL-C, TG, TC, and MDA, enhanced HDL-C levels, SOD and GSH activities, reduced ROS accumulation in cells, and activated the Nrf2 pathway, a transcription factor involved in antioxidant defense. By regulating the PI3K/Akt and STAT3/NF-κB pathways, HSYA exhibits notable antioxidative stress, anti-inflammatory, and anti-apoptotic effects, effectively impeding ALD's advancement. To further confirm the regulatory effect of HSYA on PI3K/Akt and downstream signaling pathways, the PI3K activator 740 Y-P was used and was found to reverse the downregulation of PI3K by HSYA CONCLUSION: This study supports the effectiveness of HSYA in reducing ALD by regulating the PI3K/Akt and STAT3/NF-κB pathways, indicating its potential medicinal value.

Synthesis and crystal structure of (2E)-1-[3,5-bis-(benz-yloxy)phen-yl]-3-(4-eth-oxy-phen-yl)prop-2-en-1-one

In the title compound, C31H28O4, the phenyl rings of the chalcone unit subtend a dihedral angle of 26.43 (10)°. The phenyl rings of the pendant benz-yloxy groups are orientated at 75.57 (13) and 75.70 (10)° with respect to their attached ring. In the crystal, weak C-H⋯O and C-H⋯π inter-actions link the mol-ecules. The inter-molecular inter-actions were qu-anti-fied and analysed using Hirshfeld surface analysis, which showed a breakdown into H⋯H (49.8%), H⋯C/C⋯H (33.8%) and H⋯O/O⋯H (13.6%) inter-actions with other types making negligible contributions.

Synthesis of Stereodefined Enones from the Cross-Electrophile Coupling of Activated Acrylic Acids with Alkyl Bromides

We report a one-pot synthesis of (E)-trisubstituted enones from acrylic acids through the in situ generation of a 2-pyridyl ester and subsequent cross-electrophile coupling with a nickel catalyst under reducing conditions. The scope of trisubstituted enones is broad and compatible with functionality that can be challenging in established olefination techniques. We highlight conditions necessary to suppress undesired side reactions from the α,β-unsaturated carbonyl and improve cross-electrophile coupling approaches to prepare enones.

Trapping of thermally generated ortho- and para-quinone methides by imidazoles and pyrazoles: a simple route to green synthesis of benzopyrone-azole hybrids and their evaluation as α-glucosidase inhibitors

An efficient green approach for the trapping of in situ generated ortho-and para-quinone methide intermediates by imidazoles and pyrazoles has been developed. A wide range of quinone methide precursors based on simple phenols are compatible with the experimental protocol under mild thermal conditions. This methodology was demonstrated to be suitable for the synthesis of methylene-linked benzopyrone-azole hybrids using naturally occurring coumarin and chromone Mannich bases. In most cases, the products were isolated in good to excellent yields without chromatographic purification. In vitro studies showed that some of the synthesized compounds exhibit inhibitory activity towards α-glucosidase.

Rationale, in silico docking, ADMET profile, design, synthesis and cytotoxicity evaluations of phthalazine derivatives as VEGFR-2 inhibitors and apoptosis inducers

New phthalazine derivatives as vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitors were synthesized joined to different spacers including pyrazole, α,β-unsaturated ketonic fragment, pyrimidinone and/or pyrimidinthione. A docking study was carried out to explore the suggested binding orientations of the novel derivatives inside the active site of VEGFR-2. The obtained biological data were extremely interrelated to that of the docking study. In particular, compounds 4b and 3e showed the highest activities against Michigan Cancer Foundation-7 (MCF-7) and Hepatocellular carcinoma G2 (HepG2) with half maximal inhibitory concentration (IC50) = 0.06, 0.06 μM and 0.08, 0.19 μM respectively. Our derivatives 3a-e, 4a,b and 5a,b were evaluated for their cytotoxicity against normal VERO cells. Our compounds exhibited low toxicity concerning normal VERO cells with IC50 = 3.00-4.75 μM. In addition, our final derivatives 3a-e, 4a, 4b, 5a and 5b were investigated for their VEGFR-2 inhibitory activities. Derivative 4b exhibited the highest VEGFR-2 inhibitory activities at an IC50 value of 0.09 ± 0.02 μM. Derivatives 3e, 4a and 5b demonstrated good activities with IC50 values = 0.12 ± 0.02, 0.15 ± 0.03 and 0.13 ± 0.03 μM respectively. Furthermore, the activities of 4b were assessed against MCF-7 cancer cells for apoptosis induction, cell cycle distribution and growth inhibition. Compound 4b caused cell growth arrest in growth 2-mitosis (G2-M) phase; accumulation of cells at that phase became 6.92% after being 13.2 in control cells. Moreover, our derivatives 3e, 4b and 5b revealed a good in silico considered absorption, distribution, metabolism, excretion, and toxicity (ADMET) profile in comparison to sorafenib.