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Chalcone

Chalcone is an open-chain flavonoid and a natural α,β-unsaturated ketone with the molecular formula C₁₅H₁₂O, featuring a 1,3-diphenylprop-2-en-1-one backbone where two aromatic rings (A and B) are linked by a three-carbon chain containing a conjugated double bond and carbonyl group.^[1] Predominantly occurring in the trans (E) configuration, it appears as a yellow crystalline solid with a melting point of 57.5 °C and serves as a crucial biosynthetic precursor to other flavonoids such as flavones and isoflavonoids in plants.^[1]^[2] Chalcones are widely distributed in nature, particularly in families like Fabaceae, Moraceae, and Asteraceae, with notable examples including Glycyrrhiza glabra (licorice), Humulus lupulus (hops), and Angelica keiskei.^[2] They are often isolated from plant extracts using solvents or synthesized in laboratories via the Claisen-Schmidt condensation, an aldol reaction between an aromatic aldehyde (e.g., benzaldehyde) and a methyl ketone (e.g., acetophenone) under basic or acidic conditions, yielding up to 95% with modern microwave- or ultrasound-assisted methods.^[3] This straightforward synthesis contributes to their appeal as versatile scaffolds for derivatization, including hydroxylation, methoxylation, or hybridization with heterocycles to enhance bioactivity.^[3] The pharmacological significance of chalcones stems from their diverse biological activities, including potent anticancer, anti-inflammatory, antimicrobial, antidiabetic, and antioxidant effects, often mediated through mechanisms such as enzyme inhibition (e.g., COX-2, α-glucosidase), apoptosis induction, and modulation of signaling pathways like NF-κB or EGFR.^[2]^[3] For instance, derivatives like licochalcone A exhibit cytotoxicity against breast cancer cells (MCF-7, IC₅₀ ~22 µM)^[4] and inhibit microbial pathogens including Candida albicans and Staphylococcus aureus, while xanthohumol shows antidiabetic potential by enhancing insulin secretion and reducing blood glucose in preclinical models.^[2] Clinical applications include topical formulations for chronic venous insufficiency and rosacea, underscoring their transition from natural metabolites to promising therapeutic agents.^[2]

Structure and Properties

Molecular Structure

Chalcone is an α,β-unsaturated ketone consisting of two aromatic rings (A and B) connected by a three-carbon α,β-unsaturated carbonyl system, with the parent compound having the molecular formula C₁₅H₁₂O.^[5] The systematic IUPAC name for this parent structure is (2E)-1,3-diphenylprop-2-en-1-one, where the two phenyl groups are attached to the terminal carbons of the prop-2-en-1-one chain.^[6] The core structural feature is the enone moiety, in which the carbonyl group (C=O) is conjugated with an adjacent carbon-carbon double bond (C=C), enabling extended π-electron delocalization across the system.^[5] This double bond adopts the trans (E) configuration in the stable form, positioning the aryl substituents on opposite sides for minimal steric hindrance. Typical chalcone derivatives retain this scaffold but may include substituents such as hydroxyl, methoxy, or alkyl groups on the aromatic rings, with phenyl groups serving as the unsubstituted example at positions 1 and 3.^[5] In skeletal formula representation, chalcone is depicted as a linear chain with the carbonyl attached to one phenyl ring and the trans-alkene linking to the second phenyl ring, often shown as:

  Ph
   |
C=O
   |
  CH=CH
   |
  Ph
  Ph
   |
C=O
   |
  CH=CH
   |
  Ph

where Ph denotes phenyl and the double bond is trans. The term "chalcone" derives from the Greek word chalcos, meaning bronze, reflecting the characteristic yellowish-bronze color of many naturally occurring chalcones.^[7] Chalcone serves as a central intermediate in the biosynthesis of flavonoids.^[5]

Physical and Chemical Properties

Chalcone, the parent compound (E)-1,3-diphenylprop-2-en-1-one, appears as a yellow crystalline solid or powder.^[1]^[8] Its melting point is 55–57 °C.^[8] The compound exhibits good solubility in organic solvents such as ethanol, acetone, and dichloromethane, but it is poorly soluble in water.^[9] In terms of spectroscopic properties, chalcone displays UV-Vis absorption maxima around 300 nm, attributable to its extended conjugated π-system.^[10] Infrared spectroscopy reveals a characteristic carbonyl stretching frequency at approximately 1650–1680 cm⁻¹ for the α,β-unsaturated ketone moiety.^[11] In ¹H NMR spectra, the trans-alkene protons typically appear as doublets between 6.5 and 7.5 ppm, with a coupling constant of about 15–16 Hz confirming the E configuration.^[12] Chemically, chalcone acts as a Michael addition acceptor owing to its α,β-unsaturated carbonyl system, facilitating nucleophilic conjugate additions.^[13] It is susceptible to base-catalyzed cyclization, such as isomerization to flavanones under alkaline conditions.^[14] Under standard ambient conditions, chalcone remains air-stable but can decompose or react in the presence of strong acids or bases.^[1]

Natural Occurrence and Biosynthesis

Natural Sources

Chalcones are abundant in higher plants, particularly within the families Fabaceae (formerly Leguminosae), Asteraceae, and Moraceae, where they occur as secondary metabolites in various tissues including roots, leaves, and fruits.^[15] These compounds contribute to the chemical diversity of these plant groups, with over 300 naturally occurring chalcones identified across species in these families.^[16] Representative examples include isoliquiritigenin (4,2',4'-trihydroxychalcone), a key chalcone isolated from the roots of licorice (Glycyrrhiza glabra, Fabaceae), where it constitutes a significant portion of the flavonoid content.^[17] Xanthohumol, a prenylated chalcone, is prominently found in the female inflorescences (cones) of hops (Humulus lupulus, Cannabaceae), serving as a precursor to other prenylated flavonoids.^[18] In fruits like apples (Malus domestica, Rosaceae), chalcones such as naringenin chalcone act as intermediates in the biosynthesis of dihydrochalcones like phloridzin, accumulating in leaves and peels.^[19] Additionally, dragon's blood resin from the Socotran dragon's blood tree (Dracaena cinnabari, Asparagaceae) contains unique chalcone derivatives, extracted from the red exudate.^[20] Microbial sources of chalcones are rare, though chalcone synthase-like enzymes capable of producing naringenin chalcone have been functionally characterized in certain fungi, such as Aspergillus species.^[21] Natural chalcones are typically extracted from plant materials using solvent-based methods, such as methanol or ethanol extraction under reflux or ultrasonic assistance, often followed by chromatographic purification.^[7] Yields vary by plant species and extraction conditions; for instance, isoliquiritigenin recovery from licorice roots ranges from 0.02% to 0.3% of dry weight.^[22] These methods prioritize efficiency while preserving the compounds' structural integrity. In their ecological role, chalcones function as phytoalexins, antimicrobial secondary metabolites that plants accumulate in response to pathogen attack, wounding, or environmental stress, thereby enhancing defense mechanisms.^[23] Concentrations of chalcones, such as those derived from chalcone synthase activity, can increase rapidly—often within hours—under elicitor-induced stress, contributing to localized toxicity against fungi, bacteria, and herbivores.^[24]

Biosynthetic Pathways

Chalcone biosynthesis primarily occurs within the phenylpropanoid pathway in plants, where it serves as the foundational step for flavonoid production. The key enzyme, chalcone synthase (CHS), a type III polyketide synthase, catalyzes the initial committed reaction by condensing one molecule of p-coumaroyl-CoA with three molecules of malonyl-CoA. This process involves sequential decarboxylative condensations followed by a Claisen-type cyclization to form the chalcone scaffold, specifically naringenin chalcone.^[25]^[26] The overall reaction can be represented as:

\text{p-Coumaroyl-CoA} + 3 \text{ Malonyl-CoA} \rightarrow \text{Naringenin chalcone} + 4 \text{ CoA} + 3 \text{ CO}_2

This enzymatic transformation proceeds through the loading of the p-coumaroyl starter unit onto the active site cysteine residue of CHS, followed by iterative extensions with malonyl-derived acetyl units and decarboxylations, culminating in the release of the tetraketide chalcone product. CHS is a homodimeric enzyme with conserved active site residues, such as Cys164 for nucleophilic attack and His303 for facilitating decarboxylation, ensuring efficient polyketide assembly.^[25]^[27] Following chalcone formation, the pathway advances through isomerization mediated by chalcone isomerase (CHI), which stereospecifically converts the chalcone to the flavanone (2S)-naringenin via an acid-base catalyzed mechanism. This step is crucial for downstream flavonoid diversification. The entire process is tightly regulated within the phenylpropanoid pathway by transcription factors, such as MYB proteins and bHLH factors, which bind to promoter elements like G-box (CACGTG) and H-box (CCTACC) sequences to respond to environmental cues including UV irradiation, pathogen attack, and wounding.^[25]^[28] While the canonical pathway is plant-specific, variations exist in other organisms. In fungi, such as Aspergillus nidulans and Colletotrichum fragariae, non-reducing polyketide synthases (e.g., AT-PKS modules like DiapA) produce chalcones using alternative starters like 4-hydroxybenzoic acid instead of p-coumaroyl-CoA, often coupled with fungal CHIs for flavanone formation. Bacterial homologs of CHS have been identified in species like Streptomyces, employing similar type III PKS mechanisms but adapted for microbial secondary metabolism. These variations highlight the evolutionary plasticity of polyketide biosynthesis.^[21] CHS and the associated pathway exhibit evolutionary conservation across angiosperms, with multigene families arising from gene duplications that enable functional diversification, such as tissue-specific expression or stress responses, tracing back to early land plants. This conservation underscores chalcone's role in plant adaptation and defense.^[25]^[29]

Synthesis

Laboratory Synthesis

The laboratory synthesis of chalcone primarily relies on the Claisen-Schmidt condensation, a base-catalyzed aldol reaction between an aromatic aldehyde, such as benzaldehyde, and an aliphatic methyl ketone, such as acetophenone.^[30] This method produces the α,β-unsaturated ketone characteristic of chalcones, with the trans isomer predominating due to thermodynamic stability.^[31] The general reaction equation is:

\text{ArCHO} + \text{Ar'COCH}_3 \rightarrow \text{ArCH=CHCOAr'} + \text{H}_2\text{O}

where Ar and Ar' represent aryl groups.^[32] Classical conditions involve treating equimolar amounts of the aldehyde and ketone with a base catalyst, such as sodium hydroxide (NaOH), in ethanol or methanol solvent at room temperature or with mild heating (typically 1–24 hours).^[30] Yields often exceed 90%, with trans stereoselectivity greater than 90%, and the product is commonly purified by recrystallization from ethanol or aqueous ethanol.^[33] This condensation was first reported in the 1880s by Ludwig Claisen and J. Gustav Schmidt, marking a foundational technique in organic synthesis.^[34] For substituted chalcones, variants employ organometallic reagents, such as Grignard reagents derived from aryl halides, which react with aldehydes to form allylic alcohols that are subsequently oxidized to the chalcone framework.^[35]

Advanced Synthetic Methods

Advanced synthetic methods for chalcone production have evolved significantly since the early 2000s, emphasizing sustainability, efficiency, and selectivity through catalyst-free, organocatalytic, and green techniques. Catalyst-free approaches, such as base- or acid-promoted Claisen-Schmidt condensations, enable metal-free synthesis under mild conditions, often achieving yields exceeding 95% in solvent-free environments. For instance, grinding acetophenone and benzaldehyde derivatives with NaOH at room temperature for 10 minutes produces chalcones with 75-99% yields, offering a simple, scalable alternative to classical methods that typically require longer reaction times and organic solvents. Organocatalytic strategies further enhance precision, utilizing amino acid-derived catalysts like L-proline or cinchona alkaloid squaramides to promote asymmetric transformations. These catalysts facilitate the synthesis of enantioenriched chalcone derivatives via Michael additions or isomerizations, with enantiomeric excesses (ee) up to 99% reported in reactions involving nitroalkanes or hydroxylamines added to chalcone acceptors under solvent-free conditions.^[31] Photocatalytic methods represent a cutting-edge innovation for stereocontrol, employing visible light and organocatalysts to direct the formation of axially chiral chalcones. Chiral secondary amine catalysts enable vinylogous domino isomerizations of exocyclic dihydronaphthalenes, yielding axially chiral products with good to excellent ee values (up to 95%) in high yields (80-90%) at room temperature.^[36] Green methodologies prioritize environmental compatibility, including microwave-assisted Claisen-Schmidt reactions in ionic liquids like [hmim]OAc, which accelerate synthesis to under 10 minutes with yields >95% while allowing catalyst recycling up to five cycles. Solvent-free grinding and ultrasound-assisted protocols similarly boost efficiency; for example, ultrasound in ethanol with NaOH produces benzofuran-derived chalcones in good yields (70-90%) at ambient temperature, reducing energy consumption compared to traditional heating. Engineered chalcone synthase (CHS) variants, guided by machine learning, mimic enzymatic pathways for biocatalytic synthesis, optimizing malonyl-CoA utilization to selectively produce chalcone intermediates with enhanced titers in cell-free systems.^[37]^[31] Heteroaromatic chalcones, incorporating rings like pyridine or thiophene, are accessed through pre-condensation modifications such as Suzuki coupling, followed by Claisen-Schmidt condensation. Copper-based magnetic nanocatalysts facilitate the coupling of pyridyl halides with boronic acids in aqueous media, yielding 49-94% for subsequent chalcone formation under mild conditions (room temperature to reflux). Microwave-assisted or sonochemical variants enhance these processes; for thiophene-containing chalcones, solvent-free microwave irradiation with base catalysts delivers >82% yields in minutes, while sonication promotes pyrazolopyridyl hybrids with high efficiency. Acid-catalyzed solvent-free routes for thienyl chalcones also provide very good yields (85-95%), emphasizing the versatility of these advanced methods for diversifying chalcone scaffolds beyond classical aromatic systems.^[38]

Biological Activities

Pharmacological Effects

Chalcones and their derivatives exhibit significant anti-inflammatory effects primarily through the inhibition of key inflammatory pathways, such as cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-κB). For instance, isoliquiritigenin, a natural chalcone from licorice root, has been shown to suppress NF-κB activation and reduce pro-inflammatory cytokine production in lipopolysaccharide-stimulated models, leading to decreased edema and inflammation in animal studies.^[39]^[40] Other chalcone derivatives inhibit COX-2 activity and downstream mediators like prostaglandin E2 and inducible nitric oxide synthase, demonstrating efficacy in preclinical models of arthritis and colitis.^[41]^[42] In anticancer applications, chalcones promote apoptosis and inhibit topoisomerase II, disrupting DNA replication in malignant cells. Prenylated chalcones, such as xanthohumol from hops, have garnered attention in recent reviews for their potency against breast cancer cell lines, including MCF-7 and MDA-MB-231, with IC₅₀ values typically ranging from 1 to 10 μM. These compounds suppress cell proliferation, invasion, and metastasis in vitro and xenograft models, highlighting their therapeutic potential without excessive toxicity to normal cells.^[43]^[44]^[45] Antimicrobial properties of chalcones target bacterial, fungal, and viral pathogens through membrane disruption and enzyme inhibition. Derivatives like licochalcone A and isobavachalcone exhibit broad-spectrum activity against methicillin-resistant Staphylococcus aureus (MRSA) and fungi such as Candida albicans, with minimum inhibitory concentrations often below 50 μM in preclinical assays. Additionally, chalcones demonstrate antiviral effects by inhibiting HIV integrase and other viral enzymes, reducing viral replication in cell-based models.^[46]^[47]^[48] Beyond these, chalcones display antioxidant activity via free radical scavenging, mitigating oxidative stress in various disease models. In antidiabetic contexts, compounds like 2-hydroxychalcone activate peroxisome proliferator-activated receptor gamma (PPARγ), improving insulin sensitivity and reducing hyperglycemia in streptozotocin-induced diabetic rodents. Safety profiles indicate low toxicity, with oral doses up to 100 mg/kg showing no significant adverse effects in rodent studies, supporting their advancement toward clinical use.^[15]^[49]^[39]

Mechanisms of Action

Chalcones exert their biological effects primarily through interactions with nucleophilic sites in proteins, often via the α,β-unsaturated carbonyl (enone) moiety acting as a Michael acceptor. This electrophilic group facilitates covalent binding to thiol groups on cysteine residues, enabling modulation of key regulatory proteins. For instance, chalcones such as sofalcone covalently bind to cysteine residues in Kelch-like ECH-associated protein 1 (Keap1), disrupting the Keap1-Nrf2 interaction and promoting Nrf2 nuclear translocation to activate antioxidant response elements (ARE). This mechanism enhances expression of heme oxygenase-1 (HO-1) and other cytoprotective genes, contributing to anti-inflammatory and cytoprotective effects.^[50]^[51] In enzyme inhibition, chalcones dock into active sites of critical enzymes, with the enone system playing a pivotal role in binding affinity as revealed by structure-activity relationship (SAR) studies. For topoisomerases, chalcone derivatives like carbazole-chalcone hybrids act as non-intercalative catalytic inhibitors of topoisomerase II (Topo II), stabilizing the enzyme-DNA cleavage complex through π-stacking interactions between the chalcone's aromatic rings and DNA bases, thereby preventing DNA religation and inducing apoptosis in cancer cells. Similarly, chalcones inhibit kinases such as epidermal growth factor receptor (EGFR) by occupying the ATP-binding pocket, where the enone facilitates hydrogen bonding and hydrophobic interactions; SAR analyses indicate that electron-withdrawing substituents on the aryl rings enhance potency by stabilizing the enone conformation for optimal docking.^[52]^[53]^[54]^[55] Chalcones also modulate nuclear receptors and disrupt microbial membranes. They exhibit partial agonism at estrogen receptor alpha (ERα) through structural mimicry of estradiol's phenolic aryl rings, binding to the ligand-binding domain and inducing conformational changes that recruit coactivators for selective gene transcription. In antimicrobial contexts, chalcones like isobavachalcone perturb bacterial membranes by inserting the hydrophobic aryl-enone scaffold into lipid bilayers, increasing permeability and causing leakage of cellular contents without significantly affecting eukaryotic cells. Recent structural studies, including 2024 molecular dynamics simulations of chalcone-EGFR complexes, highlight how enone-mediated covalent adducts enhance selectivity. Additionally, chalcones generate reactive oxygen species (ROS) selectively in cancer cells by inhibiting thioredoxin reductase and upregulating NADPH oxidase 4 (NOX4), leading to oxidative stress, unfolded protein response, and apoptosis while sparing normal cells due to their lower baseline ROS levels.^[56]^[57]^[58]^[59]

Applications

Medicinal Applications

Chalcones, particularly licochalcone A derived from licorice root, have advanced into clinical applications primarily in dermatology through topical formulations. In a multicenter prospective observational trial, a moisturizer containing licochalcone A combined with salicylic acid and other agents demonstrated significant reductions in inflammatory and non-inflammatory acne lesions by 41-71% after 8 weeks of use, with excellent tolerability in 90% of patients and minimal side effects.^[60] Similarly, emollients enriched with licochalcone A have been effective in preventing flares in atopic dermatitis, reducing symptom severity by enhancing skin barrier function and decreasing erythema in a clinical study involving adults.^[61] These applications leverage the compound's anti-inflammatory potencies to translate preclinical effects into practical therapeutic outcomes for common skin disorders. Nutraceutical supplements based on licorice extracts, which naturally contain licochalcone A, are utilized for supportive management of inflammatory skin conditions such as eczema, rosacea, and psoriasis. These oral formulations provide systemic anti-inflammatory benefits, attributed to the inhibition of pro-inflammatory cytokines. In the cosmeceutical domain, licochalcone A is incorporated into sunscreens and skincare products for UV protection, where it mitigates radiation-induced oxidative stress and erythema; a vehicle-controlled study showed significant reduction in UV-triggered skin redness at 24 hours post-exposure.^[62] Such products offer adjunctive photoprotection, enhancing skin resilience without compromising safety in daily use. Recent developments in chalcone-based therapies extend to neurodegenerative diseases, with 2024–2025 research highlighting derivatives for Alzheimer's disease through amyloid inhibition. A 2025 study evaluated novel chalcone derivatives, demonstrating their ability to inhibit amyloid-beta aggregation and exhibit neuroprotective effects in cellular models, suggesting potential for brain-targeted interventions.^[63] Chalcones have also been used in topical formulations for chronic venous insufficiency, improving symptoms in clinical settings.^[2] While still preclinical for neurodegeneration, these findings underscore chalcones' role in multi-target strategies against amyloid pathology. Natural chalcones in licorice extracts hold Generally Recognized as Safe (GRAS) status from the FDA for use in foods and cosmetics, with recommended safe daily intake of glycyrrhizin not exceeding 100 mg.^[64] Bioavailability challenges, including poor aqueous solubility, are being overcome via glycosylation, which improves absorption and stability as shown in enzymatic modification studies enhancing chalcone uptake in biological systems.^[65]

Industrial and Synthetic Applications

Chalcones are utilized in the dye and pigment industry owing to their chromophoric properties, which enable vibrant coloration in textiles and other materials. For instance, isosalipurposide, a natural chalcone extracted from Acacia cyanophylla flowers, has been employed as a dye for wool fabrics, yielding yellow shades with good to excellent fastness properties against washing, light, and rubbing, making it suitable for eco-friendly industrial dyeing processes. Synthetic chalcone derivatives, such as mono azo thiobarbituric acid-based disperse dyes, exhibit strong absorption in the visible region and high color strength, facilitating their application in polyester dyeing with enhanced thermal stability up to 300°C. In polymer applications, chalcones function as UV absorbers to enhance light stability in plastics and coatings. Chalcone-containing polymers absorb UV radiation effectively, undergoing crosslinking to improve resistance to photodegradation and solvent penetration, as demonstrated in polyetherketone derivatives with pendant chalcone moieties that maintain structural integrity under prolonged exposure. These properties position chalcones as additives in optoelectronic materials and protective coatings for industrial plastics. As synthetic intermediates, chalcones serve as versatile precursors for heterocycles in organic synthesis, particularly through cyclization reactions to form pyrazoles and flavones. Reaction of chalcones with hydrazines yields pyrazole derivatives via regioselective 1,3-dipolar cycloaddition, while oxidative cyclization transforms them into flavones, enabling efficient production of bioactive scaffolds with yields often exceeding 70%. Recent studies highlight bis-chalcone derivatives in liquid crystal materials, where 2023 investigations into imine-based chalcone-ester mesogens revealed enantiotropic smectic C and nematic phases, supporting applications in display technologies due to tunable thermal stability.^[66]^[67] In material science, chalcone units are incorporated into photoresponsive polymers for reversible crosslinking via [2+2] photodimerization under UV light, allowing controlled solubility changes and patterning in photolithography. These polymers, such as those with pendant 4-methacryloyloxyphenyl chalcone groups, achieve crosslinking in 10-15 minutes, with potential in microelectronics for precision fabrication. Chalcones also act as intermediates in agrochemical production, forming the basis for eco-friendly pesticides; for example, derivatives like (E)-2-(2-(3-oxo-3-(thiophen-2-yl)prop-1-enyl)phenoxy)acetic acid exhibit herbicidal activity against weeds such as Chinese amaranth, aligning with sustainable pest control strategies that reduce chemical pesticide use by up to 50%.^[68] Cost-effective scale-up of chalcone production is facilitated by continuous flow methods, which enable high yields and industrial viability. Continuous-flow Claisen-Schmidt condensations of aldehydes and acetophenones achieve yields of 85-99% for deuterium-labeled antidiabetic chalcones, with reactor scalability supporting gram-to-kilogram production while minimizing waste and enhancing safety over batch processes.

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Anti-inflammation of isoliquiritigenin via the inhibition of NF-κB and ...
Aug 19, 2022 · This study was conducted to explore the protective efficacy and related mechanism of ISL against lipopolysaccharide (LPS)-stimulated oxidation and inflammation
[41]
Promising anti-inflammatory effects of chalcones via inhibition of ...
Aug 6, 2025 · This review focuses on the anti-inflammatory effects of chalcones, caused by their inhibitory action primarily against the activities and ...
[42]
Pharmacological Properties of Chalcones: A Review of Preclinical ...
The nitrogen-containing chalcone derivatives showed inhibition of some enzymes implicated to inflammatory process such as β-glucuronidase, COX-2, and trypsin ( ...
[43]
Pharmacological potential of natural chalcones: a recent studies and ...
Jun 17, 2025 · Natural chalcones have an intense antimicrobial activity that targets many pathogens, including viruses, bacteria, fungi, and protozoa.
[44]
Anticancer Activity and Mechanism of Xanthohumol: A Prenylated ...
May 21, 2018 · Numerous studies have demonstrated the anticancer activity of xanthohumol (Xn), a prenylated flavonoid isolated from hops (Humulus lupulus L.), with a ...Missing: IC50 | Show results with:IC50
[45]
Antiinvasive effect of xanthohumol, a prenylated chalcone present in ...
Aug 6, 2025 · In detail, antiproliferative and cytotoxic effects of XN are described for the human breast cancer cell line MCF7 (IC 50 ¼ 3.47 mmol/L), which ...
[46]
Antiviral and antimicrobial applications of chalcones and their ... - NIH
Chalcones and their derivatives have displayed excellent potential for combating pathogenic bacteria and fungi (especially, multidrug-resistant bacteria).
[47]
Pharmacological potential of natural chalcones: a recent studies and ...
Natural chalcones have an intense antimicrobial activity that targets many pathogens, including viruses, bacteria, fungi, and protozoa.
[48]
Preliminary Insight of Pyrrolylated-Chalcones as New Anti ... - NIH
Sep 1, 2021 · The overall results suggest that the pyrrolylated-chalcones may be considered as a potential inhibitor in the design of new anti-MRSA agents.Missing: HIV | Show results with:HIV
[49]
Effect of 2-hydroxychalcone on adiponectin level in type 2 diabetes ...
2-Hydroxychalcone treatment increased PPAR-γ levels in adipose tissue, reduced oxidative stress, restored adiponectin levels and decreased high glucose levels ...
[50]
Sofalcone, a gastroprotective drug, covalently binds to KEAP1 to ...
Dec 15, 2019 · Sofalcone activated the Nrf2-HO-1 pathway by covalently binding to KEAP1 via Michael addition, and may confer anti-colitic effects by inducing Nrf2 activation.
[51]
Chemical reactivity and biological activity of chalcones and other α,β ...
HO-1 expression is triggered by the Nrf2-Keap1 signalling pathway, initiated by the addition of chalcones to thiol groups of Keap1 via Michael-type reaction.
[52]
Synthesis of carbazole derivatives containing chalcone analogs as ...
Feb 10, 2018 · Further mechanism studies revealed that CDCAs function as non-intercalative Topo II catalytic inhibitors. Moreover, some CDCAs showed micromolar ...
[53]
Chalcones: Promising therapeutic agents targeting key players and ...
Jan 5, 2023 · Another study revealed that the function of topoisomerase II was inhibited more strongly by heteroaromatic ringincorporated chalcone ...
[54]
Design, in silico studies and biological evaluation of novel ... - Nature
Nov 4, 2024 · The present study showed the inhibitory effect of the six compounds against total EGFR. The most potent EGFR inhibitors were 3e and 3f with IC 50 = 0.031 μM ...
[55]
Design, synthesis and bioevaluation of novel prenylated chalcones ...
Jan 1, 2024 · Due to the presence of a conjugated enone system, chalcones are very reactive species and display a wide range of biological activities ...
[56]
Loureirin C, from Chinese Dragon's Blood (Dracaena ... - PubMed
Apr 3, 2023 · In our study, we found that loureirin C targeted to ERα and had partial-agonistic activity using molecular docking prediction and dual- ...
[57]
Fragment optimized chalcone derivatives targeting OmpA protein as ...
Jan 31, 2025 · The study presents an in silico analysis of chalcone derivatives as potential therapeutic agents against the outer membrane protein A (OmpA) ...
[58]
A synthetic chalcone, 2'-hydroxy-2,3,5'-trimethoxychalcone triggers ...
DK143 causes selective ROS accumulation in cancer cells. •. DK143-induced apoptosis is induced by the ROS-mediated unfolded protein response.
[59]
Chalcone suppresses tumor growth through NOX4-IRE1α ...
Chalcone was demonstrated to trigger endoplasmic reticulum (ER) stress-induced apoptosis through sulfonation of IRE1α by ER-localized NADPH oxidase 4 (NOX4).Missing: killing | Show results with:killing
[60]
Licochalcone A in Combination with Salicylic Acid as Fluid Based ...
The aim of this study was to assess the efficacy and tolerability of a new daily cosmetic regimen in the treatment of mild facial acne.
[61]
Stand-alone Emollient Treatment Reduces Flares After ...
Feb 26, 2018 · Therefore we investigated the efficacy of a water-in-oil emollient, containing licochalcone A, omega-6-fatty acids, ceramide 3 and glycerol, for ...<|control11|><|separator|>
[62]
Licorice Extract for Skin: The Complete Guide - Byrdie
Jul 31, 2024 · Offers anti-inflammatory benefits: While the flavonoid is anti-inflammatory itself, there's yet another molecule, licochalcone A, which inhibits ...
[63]
Anti-irritative efficacy of licochalcone A-containing formulations on ...
The lotion with 0.05% licochalcone significantly (P < . 05) reduced erythema at 5 hours as well as 24 hours after solar-simulated irradiation. Taken together, ...Missing: cosmeceuticals protection
[64]
Chalcone derivate as a promising candidate for treating Alzheimer's ...
Jan 9, 2025 · Chalcones are polyphenolic compounds of natural origin with a wide range of biological activities2, and emerging studies have reported ...Missing: nanoparticles | Show results with:nanoparticles
[65]
Enzymatic Glycosylation of 4′-Hydroxychalcones: Expanding the ...
The enzymatic glycosylation of the 4′-hydroxychalcones explored in this study aligns with the broader research trend focusing on enhancing the bioavailability ...
[66]
https://doi.org/10.1021/acsomega.3c01035
[67]
https://doi.org/10.1016/j.molliq.2023.121719
[68]
https://doi.org/10.3390/molecules29102247