Synthesis, anticancer and antioxidant activities of 2,4,5-trimethoxy chalcones and analogues from asaronaldehyde: Structure–activity relationship

Excavating medicinal virtues of chalcones to illuminate a new scope in cancer chemotherapy

A common simple scaffold, 1,3-diaryl-2-propen-1-one (also known as chalcone), is present in many important natural products. This scaffold is the backbone of several flavonoids and isoflavonoids. Owing to the simple approachable synthetic strategies and the rigid backbone of chalcone and its derivatives, they have captivated the attention of researchers for several decades. Chalcone and its derivatives possess strong biological activities, viz. anti-tumor activity and anticancer potency. Accordingly, the in vitro and in vivo anticancer activities of several chalcone-based compounds with strong anticancer potential have been identified, which relies on mechanisms such as cell cycle arrest, regulation of autophagy, and induction of apoptosis. Therefore, researchers have successfully introduced chalcone derivatives to achieve enhanced anticancer activity in traditional chemotherapy. Nevertheless, in-depth research on this highly impactful scaffold is lacking to date. Thus, in this review, we shed light on the recent advances in the relatively unexplored scaffolds of chalcone and its derivatives, which have substantial anticancer activities. Furthermore, future perspectives of the mushrooming research on chalcones as potential anticancer agents (therapeutics) are emphasized.

Brominated chalcones as promising antileishmanial agents

Leishmaniasis is a group of diseases caused by protozoa of the genus Leishmania. They are considered neglected diseases and are endemic to tropical and subtropical regions, affecting thousands of people annually. Leishmaniasis has a wide global distribution, present on four continents. Various drugs have been used to control leishmaniasis; however, obstacles such as high toxicity to patients and the occurrence of resistance have led to the search for alternatives. Chalcones are α, β-unsaturated ketones that can occur in the secondary metabolism of plants or can be obtained through organic synthesis. In this study, 21 chalcones brominated were synthesized via the Claisen-Schmidt condensation synthesis and characterized by UHRMS and NMR. The biological activity was evaluated for antiprotozoal potential against Leishmania amazonensis and cytotoxicity against L929 fibroblasts. Eighteen chalcones showed viability inhibition rates above 80 % at a concentration of 50 µM. Six chalcones demonstrated IC50 values ranging from 6.33 ± 0.70 µM to 23.95 ± 2.94 µM and maintained 70 % viability in L929 fibroblasts at 50 µM. The (E)-1-(4-bromophenyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one, with a trimethoxylation at positions 2, 4, and 5 of ring B and a bromine substituent at position 4 of ring A, exhibited the lowest IC50 value (6.33 µM). These results indicate that these brominated chalcones have potential for studies aiming at the development of new drugs for leishmaniasis control.

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.

Synthesis, cytotoxicity, anti-inflammatory, anti-metastatic and anti-oxidant activities of novel chalcones incorporating 2-phenoxy-N-arylacetamide and thiophene moieties: induction of apoptosis in MCF7 and HEP2 cells

Eight Novel chalcones were synthesized and their structures were confirmed by different spectral tools. All the prepared compounds were subjected to SRB cytotoxic screening against several cancer cell lines. Compound 5c exerted the most promising effect against MCF7 and HEP2 cells with IC50 values of 9.5 and 12 µg/mL, respectively. Real-time PCR demonstrated the inhibitory effect of compound 5c on the expression level of Antigen kiel 67 (KI-67), Survivin, Interleukin-1beta (IL-1B), Interleukin-6 (IL-6), Cyclooxygenase-2 (COX-2) and Protein kinase B (AKT1) genes. Flow-cytometric analysis of the cell cycle indicated that compound 5c stopped the cell cycle at the G0/G1 and G2/M phases in MCF7 and HEP2 treated cells, respectively. ELISA assay showed that Caspase 8, Caspase 9, P53, BAX, and Glutathione (GSH) were extremely activated and Matrix metalloproteinase 2 (MMP2), Matrix metalloproteinase 9 (MMP9), BCL2, Malondialdehyde (MDA), and IL-6 were deactivated in 5c treated MCF7 and HEP2 cells. Wound healing revealed that chalcone 5c reduced the ability to close the scrape wound and decreased the number of migrating MCF7 and HEP2 cells compared to the untreated cells after 48 h. Theoretical molecular modeling against P53 cancer mutant Y220C and Bcl2 showed binding energies of -22.8 and -24.2 Kcal/mole, respectively, which confirmed our ELISA results.

Advances in chalcone-based anticancer therapy: mechanisms, preclinical advances, and future perspectives

INTRODUCTION

Cancer remains a leading cause of death worldwide with traditional treatments like chemotherapy, and radiotherapy becoming less effective due to multidrug resistance (MDR). This highlights the necessity for novel chemotherapeutics like chalcone-based compounds, which demonstrate broad anti-cancer properties and target multiple pathways. These compounds hold promise for improving cancer treatment outcomes compared to existing therapies.

AREAS COVERED

This review provides a comprehensive synopsis of the recent literature (2018-2024) for anti-proliferative/anti-cancer activity of chalcones. It includes the identification of potential targets, their mechanisms of action, and possible modes of binding. Additionally, chalcone derivatives in preclinical trials are also discussed.

EXPERT OPINION

Chalcones mark a significant stride in anticancer therapies due to their multifaceted approach in targeting various cellular pathways. Their ability to simultaneously target multiple pathways enables them to overcome drug resistance as compared to traditional therapies. With well-defined mechanisms of action, these compounds can serve as lead molecules for designing new, more promising treatments. Continued progress in synthesis and structural optimization, along with promising results from preclinical trials, offers hope for the development of more potent molecules, heralding a new era in cancer therapeutics.

Design, synthesis, molecular docking and in vitro anticancer activities of 1-(4-(benzamido)phenyl)-3-arylurea derivatives

In both premenopausal and postmenopausal women, oestrogens play a critical role in the development of breast cancer. Aromatase is an enzyme that catalyses the final step in the biosynthesis of estrogen and has emerged as a promising target for therapeutic intervention. This study aimed to design and evaluate novel 1-(4-(benzamido)phenyl)-3-arylurea derivatives as potential aromatase inhibitors. Through molecular docking, promising leads were identified and synthesized. Spectroscopic techniques confirmed their structural integrity. Cytotoxicity against various cancer cell lines was assessed using MTT assay. Docking investigations against the aromatase enzyme (3s7s) elucidated binding interactions and energies. Compound 6g, exhibiting a binding energy of -8.6 kcal mol-1 and interacting with ALA306 and THR310 residues, showed the most promising activity. It demonstrated GI50 values ranging from 14.46 μM, 13.97 μM, 11.35 μM, 11.58 μM, and 15.77 μM against A-498, NCI-H23, MDAMB-231, MCF-7, and A-549 respectively. Lastly, the physicochemical, and ADMET properties of the compound were predicted. These findings highlight the potential of 1-(4-(benzamido)phenyl)-3-arylureas as a new class of antitumor agents targeting aromatase. Their versatility and superior activity compared to standard chemotherapeutic agents, like doxorubicin, warrant further investigation for the development of broader-spectrum anticancer drugs.

New pyrazolo[3,4-d]pyrimidine derivatives as EGFR-TK inhibitors: design, green synthesis, potential anti-proliferative activity and P-glycoprotein inhibition

In this study, four series of new pyrazolo[3,4-d]pyrimidine derivatives were designed and synthesized with both green and conventional methods. All the synthesized candidates were chemically confirmed using spectroscopic methods, and the DFT of the reaction mechanism was illustrated. The anti-proliferative activity of the synthesized compounds was evaluated against NCI 60 cancer cell lines. Two compounds (15 & 16) exhibited excellent broad-spectrum cytotoxic activity in NCI 5-log dose assays against the full 60-cell panel with GI50 values ranging from 0.018 to 9.98 μM. Moreover, the enzymatic assessment of the most active derivatives 4, 15, and 16 against EGFR tyrosine kinase showed significant inhibitory activities with IC50 of 0.054, 0.135, and 0.034 μM, respectively. The quantitative real-time PCR for the P-glycoprotein effect of compounds 15 and 16 was examined and illustrated the ability to inhibit the P-glycoprotein by 0.301 and 0.449 fold in comparison to the control. Mechanistic study using reversal activity in MDA-MB-468 cell line revealed the effect of both compounds 15 and 16 cytotoxicity against DOX/MDA-MB-468 with IC50 = 0.267 and 0.844 μM, respectively. Additionally, compound 16 was found to induce cell cycle arrest at the S phase with a subsequent increase in pre-G cell population in MDA-MB-468 cell line. It also increased the percentage of apoptotic cells in a time-dependent manner. Moreover, a molecular docking study was carried out to explain the target compounds' potent inhibitory activity within the EGFR binding site.

Design, synthesis and bioevaluation of novel prenylated chalcones derivatives as potential antitumor agents

A series of novel prenylated chalcone derivatives with broad spectrum anticancer potential were designed and synthesized. Some of the synthesized target compounds showed potent anti-proliferative activities toward LNCaP (prostate cancer cell line), K562 (human leukemia cells), A549 (human lung carcinoma cell line) and HeLa (cervical cancer cell line) cell lines. Among of the active compounds, (E)-1-(4-(2-(diethylamino)ethoxy)-2-hydroxy-6-methoxy-3-(3-methylbut-2-en-1-yl)phenyl)-3-(pyridin-3-yl)prop-2-en-1-one (C36) was directly interacted with protein kinase B (PKB), also known as AKT, significantly inhibited the pPI3K, pAKT(Ser473) protein levels to repress the growth of cancer cells by inducing apoptosis, arresting cell cycle. Our studies provide support for prenylated chalcone derivatives potential applications in cancer treatment as a potential AKT inhibitor.

Novel 3-(pyrazol-4-yl)-2-(1H-indole-3-carbonyl)acrylonitrile derivatives induce intrinsic and extrinsic apoptotic death mediated P53 in HCT116 colon carcinoma

A novel series of α-cyano indolylchalcones was prepared, and their chemical structures were confirmed based on the different spectral data. Among them, compound 7f was observed to be the most effective bioactive chalcone with distinguished potency and selectivity against colorectal carcinoma (HCT116) with IC50 value (6.76 µg/mL) relative to the positive control (5 FU) (77.15 µg/mL). In a preliminary action study, the acrylonitrile chalcone 7f was found to enhance apoptotic action via different mechanisms like inhibition of some anti-apoptotic protein expression, regulation of some apoptotic proteins, production of caspases, and cell cycle arrest. All mechanisms suggested that compound 7f could act as a professional chemotherapeutic agent. Also, a molecular docking study was achieved on some selected proteins implicated in cancer (Caspase 9, XIAP, P53 mutant Y220C, and MDM2) which showed variable interactions with compound 7f with good Gibbs free energy scores.

Finding a Novel Chalcone-Cinnamic Acid Chimeric Compound with Antiproliferative Activity against MCF-7 Cell Line Using a Free-Wilson Type Approach

In this work, we carried out the design and synthesis of new chimeric compounds from the natural cytotoxic chalcone 2',4'-dihydroxychalcone (2',4'-DHC, A) in combination with cinnamic acids. For this purpose, a descriptive and predictive quantitative structure-activity relationship (QSAR) model was developed to study the chimeric compounds' anti-cancer activities against human breast cancer MCF-7, relying on the presence or absence of structural motifs in the chalcone structure, like in a Free-Wilson approach. For this, we used 207 chalcone derivatives with a great variety of structural modifications over the α and β rings, such as halogens (F, Cl, and Br), heterocyclic rings (piperazine, piperidine, pyridine, etc.), and hydroxyl and methoxy groups. The multilinear equation was obtained by the genetic algorithm technique, using logIC₅₀ as a dependent variable and molecular descriptors (constitutional, topological, functional group count, atom-centered fragments, and molecular properties) as independent variables, with acceptable statistical parameter values (R2 = 86.93, Q2_LMO = 82.578, Q2_BOOT = 80.436, and Q2_EXT = 80.226), which supports the predictive ability of the model. Considering the aromatic and planar nature of the chalcone and cinnamic acid cores, a structural-specific QSAR model was developed by incorporating geometrical descriptors into the previous general QSAR model, again, with acceptable parameters (R2 = 85.554, Q2_LMO = 80.534, Q2_BOOT = 78.186, and Q2_EXT = 79.41). Employing this new QSAR model over the natural parent chalcone 2',4'-DHC (A) and the chimeric compound 2'-hydroxy,4'-cinnamate chalcone (B), the predicted cytotoxic activity was achieved with values of 55.95 and 17.86 µM, respectively. Therefore, to corroborate the predicted cytotoxic activity compounds A and B were synthesized by two- and three-step reactions. The structures were confirmed by ¹H and ¹³C NMR and ESI+MS analysis and further evaluated in vitro against HepG2, Hep3B (liver), A-549 (lung), MCF-7 (breast), and CasKi (cervical) human cancer cell lines. The results showed IC₅₀ values of 11.89, 10.27, 56.75, 14.86, and 29.72 µM, respectively, for the chimeric cinnamate chalcone B. Finally, we employed B as a molecular scaffold for the generation of cinnamate candidates (C-K), which incorporated structural motifs that enhance the cytotoxic activity (pyridine ring, halogens, and methoxy groups) according to our QSAR model. ADME/tox in silico analysis showed that the synthesized compounds A and B, as well as the proposed chalcones C and G, are the best candidates with adequate drug-likeness properties. From all these results, we propose B (as a molecular scaffold) and our two QSAR models as reliable tools for the generation of anti-cancer compounds over the MCF-7 cell line.

Novel Tetrahydro-[1,2,4]triazolo[3,4-a]isoquinoline Chalcones Suppress Breast Carcinoma through Cell Cycle Arrests and Apoptosis

Chalcones are interesting anticancer drug candidates which have attracted much interest due to their unique structure and their extensive biological activity. Various functional modifications in chalcones have been reported, along with their pharmacological properties. In the current study, novel chalcone derivatives with the chemical base of tetrahydro-[1,2,4]triazolo[3,4-a]isoquinolin-3-yl)-3-arylprop-2-en-1-one were synthesized, and the structure of their molecules was confirmed through NMR spectroscopy. The antitumor activity of these newly synthesized chalcone derivatives was tested on mouse (Luc-4T1) and human (MDA-MB-231) breast cancer cell lines. The antiproliferative effect was evaluated through SRB screening and the MTT assay after 48 h of treatment at different concentrations. Interestingly, among the tested chalcone derivatives, chalcone analogues with a methoxy group were found to have significant anticancer activity and displayed gradient-dependent inhibition against breast cancer cell proliferation. The anticancer properties of these unique analogues were examined further by cytometric analysis of the cell cycle, quantitative PCR, and the caspases-Glo 3/7 assay. Chalcone methoxy derivatives showed the capability of cell cycle arrest and increased Bax/Bcl2 mRNA ratios as well as caspases 3/7 activity. The molecular docking analysis suggests that these chalcone methoxy derivatives may inhibit anti-apoptotic proteins, particularly cIAP1, BCL2, and EGFRK proteins. In conclusion, our findings confirm that chalcone methoxy derivatives could be considered to be potent drug candidates against breast cancer.

Theoretical and molecular mechanistic investigations of novel (3-(furan-2-yl)pyrazol-4-yl) chalcones against lung carcinoma cell line (A549)

A new chalcone series has been developed that may be useful in the treatment of lung cancer. The new series was confirmed by the different spectral tools. MTT assay was used to detect the cytotoxic effect of the novel chalcones against lung cancer cell line (A549). Molecular docking studies were performed on the most two effective chalcones 7b and 7c. Different molecular techniques were utilized to study the activity and the effect of two chalcones 7b and 7c on apoptosis of A549 cell line.

Chalcone: A Promising Bioactive Scaffold in Medicinal Chemistry

Chalcones are a class of privileged scaffolds with high medicinal significance due to the presence of an α,β-unsaturated ketone functionality. Numerous functional modifications of chalcones have been reported, along with their pharmacological behavior. The present review aims to summarize the structures from natural sources, synthesis methods, biological characteristics against infectious and non-infectious diseases, and uses of chalcones over the past decade, and their structure-activity relationship studies are detailed in depth. This critical review provides guidelines for the future design and synthesis of various chalcones. In addition, this could be highly supportive for medicinal chemists to develop more promising candidates for various infectious and non-infectious diseases.

Flavonoids as dual inhibitors of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX): molecular docking and in vitro studies

Background

Inflammation is known to involve in many pathological processes of different diseases, but the current therapy causes adverse effects. Thus, there is a great interest for the discovery of flavonoids as a valuable alternative to classical analgesic and anti-inflammatory agent with dual-inhibitory action, especially on both COX-2 and 5-LOX which can minimize or overcome this problem.

Results

In the present work, drug-likeness properties of the synthesized flavonoids via Lipinski’s Rule of Five were predicted using QikProp prior to evaluation of their COX and LOX inhibitory activities using enzyme assays. Subsequently, molecular docking was performed using GLIDE to analyse their binding behaviour. The results showed that all compounds obeyed the Lipinski’s Rule of Five. NPC6 and NPC7 had displayed better selectivity towards COX-2 as compared to Indomethacin with less than 50% inhibition against COX-1. In addition, these compounds also inhibited activity of 5-LOX. Their selectivity to COX-2 was due to the binding to hydrophobic region and extends to lobby region near the entrance of COX binding site forming hydrogen bond with Ser530. Interestingly, these compounds showed a similar binding mode as Zileuton in the active site of 5-LOX and formed hydrogen bond interaction with Ala424.

Conclusion

NPC6 and NPC7 had potential as dual inhibitor of COX-2 and 5-LOX. The scaffolds of these chemical entities are useful to be as lead compounds for the dual inhibition of COX-2 and 5-LOX.

Design and synthesis of piezochromic materials exploring intermolecular charge transfer: chalconoids bound to the p-sulfonatocalix[6]arene macrocycle

Solid-state systems composed of chalconoid encapsulated within p-sulfonatocalix[6]arene (SCX6) scaffolds that exhibit mechanochromism and thermochromism have been developed. An introduction of a supramolecular host promises a variety of applications in diverse areas, which makes them fascinating. Largely hydrogen bonding as well as π···π interactions are responsible for the host-guest complexation. The complex shows partial encapsulation of the guest with one of the phenyl rings of chalcone (guest) is held inside the SCX6 cavity, whilst other phenyl rings that exclude the cavity are hydrogen-bonded to sulfonate portals of the host. The hydrogen bonding conducing such complexation triggers proton transfer engendering a mechanochromic switch. The complexes are further characterized by a variety of experiments such as cyclic voltammetry (CV), steady-state fluorescence, vibrational spectroscopy, and ¹H or 2D NMR (NOESY) spectroscopy experiments. Detailed structure furnished through the NMR shows deshielding of the Ha-e (guest) protons whereas, the hydroxyl protons from the host experience shielding as evidenced from the ¹H NMR spectra. These inferences have further been corroborated through the density functional theory. Electrochemical investigations suggested an irreversible one-electron transfer in the host-guest binding. The characteristic 'frequency shift' for the intense carbonyl vibration in the infrared spectra, which can be correlated to the kinetic energy density parameter, G(r), in the quantum theory of atoms in molecules (QTAIM).

Synthesis of Nonsteroidal Anti-Inflammatory Drug (NSAID) 2,4,5-Trimethoxybenzaldehyde from Indonesian Calamus oil and Its In Silico Pharmacokinetic Study

Seeking Nonsteroidal anti-inflammatory painkillers are in the race due to the escalating cases of the life-threatening COVID-19 pandemic. Those current Nonsteroidal Anti-inflammatory Drugs (NSAIDs) used as an inflammation adjunct treatment on the COVID-19 patients including Paracetamol, Ibuprofen, and Celecoxib, are still under dispute offering emergency development of a new potent NSAID. Meanwhile, a well-known COX-2 selective anti-inflammation 2,4,5-trimethoxybenzaldehye has not been developed further in terms of its synthetic methodology and as well its pharmacokinetic studies. Here, an article on the synthesis of 2,4,5-trimethoxybenzaldehyde from Indonesia Sweet Flag (Acorus calamus) and as well its pharmacokinetic properties studied through in silico calculation was published. A typical Asian tetraploid calamus oil was yielded in 90% pure after doing reduced pressure distillation of the crude Indonesian Sweet flag oil. Submission of that oil into a very cheap DIY ozone machine produced 95% of pure 2,4,5-trimethoxybenzaldehyde just in 10 minutes ozonised. The in silico Adsorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) prediction using free access ADMETlab 2.0 web server strongly recommended the 2,4,5-trimethoxybenzaldehyde to be an orally administered NSAID candidate.

Antioxidant properties of butylated phenol with oxadiazole and hydrazone moiety at ortho position supported by DFT study

Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-tert-butylphenol group were synthesized. The antioxidant properties were evaluated by DPPH and FRAP assays. Compound 3 showed significant antioxidant activity, while its alkyl derivatives exhibited decreased antioxidant activity in both assays. The preferential antioxidant mechanism of the reactive antioxidant molecules prepared from the further reaction of compound 3 to produce compounds 4 and 6 was investigated using density functional theory. Calculating their comprehensive reactivity descriptors was used to assess their antioxidant reactivity. According to the calculated descriptors, compounds 4c and 6d are the most reactive antioxidants within their own group compared to the other derivative moieties. The results are identical to ascorbic acid's, indicating that they have similar activity. The experimental data and the calculated descriptors are in good agreement. The nature of the substituents and their positions have a significant impact on the derivatives' antioxidant capabilities.

Anticancer activity of novel 3-(furan-2-yl)pyrazolyl and 3-(thiophen-2-yl)pyrazolyl hybrid chalcones: Synthesis and in vitro studies

Twelve novel chalcone derivatives were prepared using the Claisen-Schmidt condensation reaction. The reaction of 4-acetyl-5-furan/thiophene-pyrazole derivatives 5 with the corresponding aldehydes 6 afforded the targeted chalcone derivatives 7a-l in good yields. The newly synthesized chalcones were fully characterized by spectrometric and elemental analyses. The in vitro anticancer activities of the novel compounds 7a-l were evaluated against four human cancer cell lines: HepG2 (human hepatocellular carcinoma), MCF7 (human Caucasian breast adenocarcinoma), A549 (lung carcinoma), and BJ1 (normal skin fibroblasts). Compound 7g emerged as the most promising compound, with IC₅₀  = 27.7 µg/ml against A549 cells compared to the reference drug doxorubicin (IC₅₀  = 28.3 µg/ml), and IC₅₀  = 26.6 µg/ml against HepG2 cells compared to the reference drug doxorubicin (IC₅₀  = 21.6 µg/ml). The gene expression and DNA damage values and the DNA fragmentation percentages for compound 7g were determined on the lung and liver cell lines. The expression levels of the AMY2A and FOXG1 genes increased significantly (p < 0.01) in the negative samples of lung cancer cells compared with treated cells. Also, the expression values of the PKM and PSPH genes improved significantly (p < 0.01) in the negative samples compared with treated samples of liver cancer cells. The DNA damage values increased significantly (p < 0.01) in treated lung cell line samples (7g) and the positive control. The results showed a significant decrease (p < 0.05) in DNA damage values in the negative samples of liver cancer cells compared to those treated with 7g. However, the DNA fragmentation values increased significantly (p < 0.01) in the treated lung and liver cell line samples compared with the negative control.

Anticancer Activity of Natural and Synthetic Chalcones

Cancer is a condition caused by many mechanisms (genetic, immune, oxidation, and inflammatory). Anticancer therapy aims to destroy or stop the growth of cancer cells. Resistance to treatment is theleading cause of the inefficiency of current standard therapies. Targeted therapies are the most effective due to the low number of side effects and low resistance. Among the small molecule natural compounds, flavonoids are of particular interest for theidentification of new anticancer agents. Chalcones are precursors to all flavonoids and have many biological activities. The anticancer activity of chalcones is due to the ability of these compounds to act on many targets. Natural chalcones, such as licochalcones, xanthohumol (XN), panduretin (PA), and loncocarpine, have been extensively studied and modulated. Modification of the basic structure of chalcones in order to obtain compounds with superior cytotoxic properties has been performed by modulating the aromatic residues, replacing aromatic residues with heterocycles, and obtaining hybrid molecules. A huge number of chalcone derivatives with residues such as diaryl ether, sulfonamide, and amine have been obtained, their presence being favorable for anticancer activity. Modification of the amino group in the structure of aminochalconesis always favorable for antitumor activity. This is why hybrid molecules of chalcones with different nitrogen hetercycles in the molecule have been obtained. From these, azoles (imidazole, oxazoles, tetrazoles, thiazoles, 1,2,3-triazoles, and 1,2,4-triazoles) are of particular importance for the identification of new anticancer agents.

Synthesis and spectroscopic characterizations of hexakis[(1-(4'-oxyphenyl)-3-(substituted-phenyl)prop-2-en-1-one)]cyclotriphosphazenes: their in vitro cytotoxic activity, theoretical analysis and molecular docking studies

The hexachlorocyclotriphosphaze compound (N₃P₃Cl₆, HCCP) was reacted with excess (E)-(1-(4'-oxyphenyl)-3-(substituted-phenyl)prop-2-en-1-ones (2-11) to produce hexakis[(1-(4-oxyphenyl)-3-(substituted-phenyl)prop-2-en-1-one)]cyclotriphosphazenes (CP 2-11). The structures of products (CP 2-11) were confirmed using elemental analysis, FT-IR, MS spectral analysis as well as ³¹P, ¹H and ¹³C-APT NMR techniques and their thermal properties determined by TGA and DSC techniques. The HOMO-LUMO energy gap and chemical reactivity identifiers were calculated and HOMO and LUMO images were viewed. According to the calculations, all the chemical potential values of CP 2-11 are negative and it shown that the molecules are stable. The in vitro cytotoxic of CP 2-11 investigated and their activity potentials were evaluated by molecular docking studies with Autodock Vina softwares. CP 2-11 compounds were found to demonstrate cytotoxic activity against human cancer cell lines (A2780, LNCaP and PC-3). The CP 2-11 compounds reduced the cell viability against all cancer cell lines in the range 36%-90% especially. The results showed that these compounds are powerful candidate molecules for pharmaceutical applications.

C3 amino-substituted chalcone derivative with selective adenosine rA1 receptor affinity in the micromolar range

ABSTRACT

To identify novel adenosine receptor (AR) ligands based on the chalcone scaffold, herein the synthesis, characterization and in vitro and in silico evaluation of 33 chalcones (15-36 and 37-41) and structurally related compounds (42-47) are reported. These compounds were characterized by radioligand binding and GTP shift assays to determine the degree and type of binding affinity, respectively, against rat (r) A1 and A2A ARs. The chalcone derivatives 24, 29, 37 and 38 possessed selective A1 affinity below 10 µM, and thus, are the most active compounds of the present series; compound 38 was the most potent selective A1 AR antagonist (K i (r) = 1.6 µM). The structure-affinity relationships (SAR) revealed that the NH2-group at position C3 of ring A of the chalcone scaffold played a key role in affinity, and also, the Br-atom at position C3' on benzylidene ring B. Upon in vitro and in silico evaluation, the novel C3 amino-substituted chalcone derivative 38-that contains an α,ß-unsaturated carbonyl system and easily allows structural modification-may possibly be a synthon in future drug discovery.

GRAPHIC ABSTRACT

C3 amino-substituted chalcone derivative (38) with C3' Br substitution on benzylidene ring B possesses selective adenosine rA1 receptor affinity in micromolar range.

Ultrasound Assisted Extraction of Phenolic Compounds from a Jujube By-Product with Valuable Bioactivities

Jujube plant is a potential source of polyphenols with biological propreties. The purpose of this study was to investigate the application of ultrasound technique for extracting phenolic compounds (TPC) from seeds of Zizyphus lotus under optimization conditions based on response surface methodology. A maximum TPC, total flavonoids content (TFC), and total condensed tannins content (TTC) of 2383.10 ± 0.87 mg GAE/100g, 486.50 ± 0.38 mg QE/100g and 15,787.10 ± 0.10 mg CE/100g, respectively obtained under ethanol concentration 50.16%, sonication temperature 29.01 °C, sonication time 15.94 min and solvent-to-solid ratio 34.10:1 mL/g. The optimized extract was then evaluated for its antioxidant, antiacethylcholinesterase, antihypercholesterolemia, and antiproliferative activities. The results showed that ultrasound method is a green and safe method that can be used to effectively extract TPC from jujube seeds. The biological activity of Zizyphus extract exhibited a very good antioxidant against DPPH (EC50 = 0.39 µg/mL) and FRAP (1670.42 ± 6.5 mg/100 g). Additionally, it possesses acetylcholinesterase (AChE) inhibitory effect (IC50 = 0.93 ± 0.01 mg/mL) and HMGR inhibition (45.41%) using 100 µg/mL. The extract significantly inhibits cell proliferation on the MCF-7 and HepG2 tumor cell lines with an IC50 values of <0.05 and 3 ± 0.55 mg/mL, respectively. Therefore, the ultrasound method can be considered a method for obtaining a significant anticancer activity with respect to the lines and therefore makes it possible to recover a maximum of phenolic compounds in less time with an AChE and HMGR inhibitory activity. Thus, it can be suggested that Zls extract is a promising fruit for the development of supplementary dietary due to its potential behaviour as nutraceutical.

Flavonoids with Inhibitory Effects on NLRP3 Inflammasome Activation from Millettia velutina

Eight new flavonoids, including two β-hydroxy/methoxychalcones, velutones A and B (1 and 2), two 1,3-diarylpropan-1-ols, velutols C and D (3 and 4), a dihydroxychalcone, velutone E (5), a chalcone, velutone F (6), a furanoflavanone, velutone G (7), and a furanoflavonol, velutone H (8), and 14 known compounds were isolated from Millettia velutina. Their structures were determined by high-resolution electrospray ionisation mass spectrometry (HR-ESIMS) and spectroscopic data analyses and time-dependent density functional theory electronic circular dichroism (TD-DFT-ECD) calculations. Among the isolated constituents, compound 6 exhibited the most potent inhibitory effect (IC₅₀: 1.3 μM) against nigericin-induced IL-1β release in THP-1 cells. The initial mechanism of action study revealed that compound 6 suppressed NLRP3 inflammasome activation via blocking ASC oligomerization without affecting the priming step, which subsequently inhibited caspase-1 activation and IL-1β secretion. Most importantly, compound 6 exerted potent protective effects in the LPS-induced septic shock mice model by improving the survival rate of mice and suppressing serum IL-1β release. These results demonstrated that compound 6 had the potential to be developed as a broad-spectrum NLRP3 inflammasome inhibitor for the treatment of NLRP3-related disease.

Novel [l,2,4]triazolo[3,4-a]isoquinoline chalcones as new chemotherapeutic agents: Block IAP tyrosine kinase domain and induce both intrinsic and extrinsic pathways of apoptosis

Two novel chemotherapeutic chalcones were synthesized and their structures were confirmed by different spectral tools. Theoretical studies such as molecular modeling were done to detect the mechanism of action of these compounds. In vitro cytotoxicity showed a strong effect against all tested cell lines (MCF7, A459, HepG2, and HCT116), and low toxic effect against normal human melanocytes (HFB4). The lung carcinoma cell line was chosen for further molecular studies. Real-time PCR demonstrated that the two compounds upregulated gene expression of (BAX, p53, casp-3, casp-8, casp-9) genes and decreased the expression of anti-apoptotic genes bcl2, CDK4, and MMP1. Flow-cytometry indicated that cell cycle arrest of A459 was induced at the G2/M phase and the apoptotic percentage increased significantly compared to the control sample. Cytochrome c oxidase and VEGF enzyme activity were detected by ELISA assay. SEM tool was used to follow the morphological changes that occurred on the cell surface, cell granulation, and average roughness of the cell surface. The change in the number and morphology of mitochondria, cell shrinkage, increase in the number of cytoplasmic organelles, membrane blebbing, chromatin condensation, and apoptotic bodies were observed using TEM. The obtained data suggested that new chalcones exerted their pathways on lung carcinoma through induction of two pathways of apoptosis. Graphical abstract Novel chalcones were prepared and confirmed by different spectral tools. Docking simulations were done to detect the mechanism of action. In vitro cytotoxicity indicated a strong effect against different cancer cell lines and low toxic effects against normal human melanocytes (HFB4). The lung carcinoma cell line was chosen for further molecular studies that include Real-time PCR, Flow-cytometry, Cytochrome c oxidase, and ELISA assay. SEM and TEM tool were used to follow the morphological changes occurred on the cell surface.

β-Lactams as promising anticancer agents: Molecular hybrids, structure activity relationships and potential targets

β-Lactam, commonly referred as azetidin-2-one, is a multifunctional building block for synthesizing β-amino ketones, γ-amino alcohols, and other compounds. Besides its well known antibiotic activity, this ring system exhibits a wide range of activities, attracting the attention of researchers. However, the structurally diverse β-lactam analogues as anticancer agents and their different molecular targets are poorly discussed. The purpose of this review is 3-fold: (1) to explore the molecular hybridization approach to design β-lactams hybrids as anticancer agents; (2) the structure activity relationship of the most active anticancer β-lactams and (3) to summarize their antitumor mechanisms.

Molecular Docking Study, Cytotoxicity, Cell Cycle Arrest and Apoptotic Induction of Novel Chalcones Incorporating Thiadiazolyl Isoquinoline in Cervical Cancer

Background:

Chalcones are naturally occurring compounds found in various plant species which are widely used for the traditional popular treatments. Chalcones are distinguished secondary metabolites that are reported to display diverse biological activities such as antiviral, antiplatelet, anti-inflammatory, anticancer, antibacterial and antioxidant agents. The presence of a,ß-unsaturated carbonyl group in chalcones is assumed to be responsible for their bioactivity. In addition, heterocyclic compounds having nitrogen such as isoquinolines are of considerable interest as they constitute the core structural element of many alkaloids that have enormous pharmacological activities.

Objective:

The objective of this study is the synthesis and biological activity of novel chalcones incorporating thiadiazolyl isoquinoline as potential anticancer candidates. Different genetic tools were used in an attempt to know the mechanism of action of this compound against breast cancer.

Methods:

An efficient one pot synthesis of novel chalcones incorporating thiadiazolyl isoquinoline has been developed. The cytotoxic activity of the novel synthesized compounds was performed against four different kinds of cancer cell lines.

Results:

Among all the tested derivatives, chalcone 3 has the best cytotoxic profile against A549, MCF7, and HeLa cell lines, with IC50s (66.1, 51.3, and 85.1μM, respectively). Molecular docking studies for chalcone 3 revealed that CDK2, and EGFRTK domains have strong binding affinities toward the novel chalcone 3, while tubulin-colchicine-ustiloxin, and VEGFRTK domains illustrated moderate mode of binding.

Conclusion:

We have developed an efficient method for the synthesis of novel chalcones incorporating thiadiazolyl isoquinoline. All compounds showed better cytotoxicity results against four kinds of cancer cell lines (A549, MCF7, HCT116, and HELA cells). The results depicted that chalcone 3 has a high and promising cytotoxic effect against HELA cell line and the mechanism of cytotoxicity was widely studied through different theoretical and experimental tools. Thus, the newly synthesized derivative 3 can be utilized as a novel chemotherapeutic compound for cervical carcinoma.

Privileged Scaffold Chalcone: Synthesis, Characterization and Its Mechanistic Interaction Studies with BSA Employing Spectroscopic and Chemoinformatics Approaches

Chalcone, a privileged structure, is considered as an effective template in the field of medicinal chemistry for potent drug discovery. In the present study, a privileged template chalcone was designed, synthesized, and characterized by various spectroscopic techniques (NMR, high-resolution mass spectrometry, Fourier transform infrared (FT-IR) spectroscopy, UV spectroscopy, and single-crystal X-ray diffraction). The mechanism of binding of chalcone with bovine serum albumin (BSA) was determined by multispectroscopic techniques and computational methods. Steady-state fluorescence spectroscopy suggests that the intrinsic fluorescence of BSA was quenched upon the addition of chalcone by the combined dynamic and static quenching mechanism. Time-resolved spectroscopy confirms complex formation. FT-IR and circular dichroism spectroscopy suggested the presence of chalcone in the BSA molecule microenvironment and also the possibility of rearrangement of the native structure of BSA. Moreover, molecular docking studies confirm the moderate binding of chalcone with BSA and the molecular dynamics simulation analysis shows the stability of the BSA-drug complex system with minimal deformability fluctuations and potential interaction by the covariance matrix. Moreover, pharmacodynamics and pharmacological analysis show good results through Lipinski rules, with no toxicity profile and high gastrointestinal absorptions by boiled egg permeation assays. This study elucidates the mechanistic profile of the privileged chalcone scaffold to be used in therapeutic applications.

Synthesis, Biological Evaluation and Docking Studies of Chalcone and Flavone Analogs as Antioxidants and Acetylcholinesterase Inhibitors

Several oxidative processes are related to a wide range of human chronic and degenerative diseases, like Alzheimer’s disease, which also has been related to cholinergic processes. Therefore, search for new or improved antioxidant molecules with acetylcholinesterase activity is essential to offer alternative chemotherapeutic agents to support current drug therapies. A series of chalcone (2a–2k) and flavone (3a–3k) analogs were synthesized, characterized, and evaluated as acetylcholinesterase (AChE) inhibitors, and antioxidant agents using 1,1-diphenyl-2-picrylhydrazyl (DPPH•), 2-2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS•), and β-carotene/linoleic acid bleaching assay. Compounds more active were 3j and 2k in DPPH with EC50 of 1 × 10−8 and 5.4 × 10−3 μg/mL, respectively; 2g and 3i in ABTS (1.14 × 10−2 and 1.9 × 10−3 μg/mL); 2e, 2f, 3f, 2j, and 3j exceeded the α-tocopherol control in the β-carotene assay (98–99% of antioxidant activity). At acetylcholinesterase inhibition assay, flavones were more active than chalcones; the best results were compounds 2d and 3d (IC50 21.5 and 26.8 µg/mL, respectively), suggesting that the presence of the nitro group enhances the inhibitory activity. The docking of these two structures were made to understand their interactions with the AChE receptor. Although further in vivo testing must be performed, our results represent an important step towards the identification of improved antioxidants and acetylcholinesterase inhibitors.

Substitution at Phenyl Rings of Chalcone and Schiff Base Moieties Accounts for their Antiproliferative Activity

BACKGROUND

In a continuous combat against cancer, which is one of the leading causes of mortality now, chalcone and Schiff bases moieties have been incorporated and their antiproliferative activities and associated mechanisms against liver (HepG2) and breast (MCF-7) cell lines in addition to normal fibroblasts (WI-38) have been examined.

METHODS

Derivatives 4 and 5 of Schiff bases only and chalcone derivatives of Schiff bases 1 and 2 were devoid of any antiproliferative activity. All three compounds (3, 6, and 7) with significant antiproliferative activity were selective and caused no growth inhibition in normal fibroblasts. Derivative 3 was a chalcone only with IC50 of ~20 µM and has a very interesting signature where it enhanced apoptosis in HepG2 by stimulating the expression of downstream execution caspase 3 without affecting neither p53 nor initiator caspase 9. In spite of the structural similarity between compounds 6 and 7, compound 6 discerned itself with a unique IC50 of ~ 10 µM.

RESULTS

The antiproliferative activity of derivative 6 could be attributed to its unique capability of formation of free radicals such as phenoxide radicals which arrested the cell cycle through enhancing the expression of p53 and induced apoptosis by induction of both caspases 9 and 3. It was the only investigated derivative that inhibited the tyrosine kinase activity by 89%.

CONCLUSIONS

The antiproliferative activity of the compounds under investigation considerably depended on the nature of the substituent at position 4 in phenyl rings of both chalcone and Schiff base fragments. Derivative 6 with electron withdrawing chlorine substitution on the phenyl ring of Schiff base fragment and an electron donating methoxy group on the phenyl ring of chalcone fragment was the most active member.

Piperidinyl-embeded chalcones possessing anti PI3Kδ inhibitory properties exhibit anti-atopic properties in preclinical models

Phosphatidylinositide 3-kinases (PI3Ks) are widely expressed enzymes involved in membrane signalization pathways. Attempts to administer inhibitors with broad activity against different isoforms have failed due to toxicity. Conversely the PI3Kδ isoform is much more selectively expressed, enabling therapeutic targeting of this isoform. Of particular interest PI3Kδ is expressed in human basophils and its inhibition has been shown to reduce anti-IgE induced basophil degranulation, suggesting that PI3Kδ inhibitors could be useful as anti-allergy drugs. Herein, we report for the first time the activity of compounds derived from chalcone scaffolds as inhibitors of normal human basophil degranulation and identified the most active compound with anti-PI3Kδ properties that was investigated in preclinical models. Compound 18, namely 1-[2-hydroxy-4,6-dimethoxy-3-(N-methylpiperidin-4-yl)phenyl]-3-(2,4,6-trimethoxyphenyl)-prop-2-en-1-one, was found to inhibit normal human basophil degranulation in a dose-dependent manner. In a murine model of ovalbumin-induced asthma, compound 18 was shown to reduce expiratory pressure while its impact on the inflammatory infiltrate in alveolar lavage and total lung was dependent on the route of administration. In a DNFB-induced model of atopic dermatitis compound 18 administered systemically proved to be as potent as topical betamethasone. These results support the anti-atopic and allergic properties of the title compound and warrant further clinical development.

Synthesis and Characterisation of New Sulfonamide Chalcones Containing an azo Group

The synthesis and characterisation of a new type of chalcone bearing a –N=N– bond is reported using an environmentally benign approach. The synthesis consists of two steps. ( E)-4-((5-acetyl-2-hydroxyphenyl)diazenyl)benzenesulfonamide was synthesised by an easy structural modification of sulfanilamide. The key step then involved the solvent-free Claisen–Schmidt condensation of benzaldehydes to form the chalcones. The structures of all compounds were confirmed by FTIR, NMR and MS spectroscopy.

Design, Synthesis and Docking Studies of Flavokawain B Type Chalcones and Their Cytotoxic Effects on MCF-7 and MDA-MB-231 Cell Lines

Flavokawain B (1) is a natural chalcone extracted from the roots of Piper methysticum, and has been proven to be a potential cytotoxic compound. Using the partial structure of flavokawain B (FKB), about 23 analogs have been synthesized. Among them, compounds 8, 13 and 23 were found in new FKB derivatives. All compounds were evaluated for their cytotoxic properties against two breast cancer cell lines, MCF-7 and MDA-MB-231, thus establishing the structure–activity relationship. The FKB derivatives 16 (IC₅₀ = 6.50 ± 0.40 and 4.12 ± 0.20 μg/mL), 15 (IC₅₀ = 5.50 ± 0.35 and 6.50 ± 1.40 μg/mL) and 13 (IC₅₀ = 7.12 ± 0.80 and 4.04 ± 0.30 μg/mL) exhibited potential cytotoxic effects on the MCF-7 and MDA-MB-231 cell lines. However, the methoxy group substituted in position three and four in compound 2 (IC₅₀ = 8.90 ± 0.60 and 6.80 ± 0.35 μg/mL) and 22 (IC₅₀ = 8.80 ± 0.35 and 14.16 ± 1.10 μg/mL) exhibited good cytotoxicity. The lead compound FKB (1) showed potential cytotoxicity (IC₅₀ = 7.70 ± 0.30 and 5.90 ± 0.30 μg/mL) against two proposed breast cancer cell lines. It is evident that the FKB skeleton is unique for anticancer agents, additionally, the presence of halogens (Cl and F) in position 2 and 3 also improved the cytotoxicity in FKB series. These findings could help to improve the future drug discovery process to treat breast cancer. A molecular dynamics study of active compounds revealed stable interactions within the active site of Janus kinase. The structures of all compounds were determined by ¹H-NMR, EI-MS, IR and UV and X-ray crystallographic spectroscopy techniques.

Cytotoxicity, molecular modeling, cell cycle arrest, and apoptotic induction induced by novel tetrahydro-[1,2,4]triazolo[3,4-a]isoquinoline chalcones

Novel tetrahydro-[1,2,4]triazolo[3,4-a]isoquinolin-3-yl)-3-arylprop-2-en-1-one derivatives were synthesized and their structures were confirmed by different spectral tools. Cytotoxicity test revealed that some compounds exhibited strong to moderate effect, while others showed weak action against different cancer cell lines (MCF7, A549, HCT116, and Hepg2). Breast carcinoma revealed higher sensitivity toward all derivatives especially compounds 5 and 8 which offered the lowest IC₅₀ values (50.05, and 27.15 μg/ml) respectively, relative to the positive control 5-fluorouracil (5-FU) (IC₅₀ = 178 μg/ml). In addition, the two compounds exhibited less toxic effect toward normal melanocytes (HFB4). Several theoretical and experimental studies were done to reveal the molecular mechanisms that control breast carcinoma metastasis using the two promising novels 5 and 8. Docking simulation studies against the two proteins EGFR and DHFR demonstrate that compound 8 showed higher binding affinity toward the two proteins more than compound 5, suggesting that trimethoxy groups may be responsible for this higher activity through the formation of five hydrogen bonding with the active domain (4r3r) and other four interactions with the active domain (1dls). Real time PCR assay illustrates that the two compounds up regulated BAX, p53, caspase-3 genes and down regulated BCL2, MMP1, CDK4 ones. In addition, it was noted that compound 8 was more effective in gene regulation and apoptotic induction than compound 5. Also, flow cytometer analysis demonstrates that both compounds 5 and 8 induced cell growth arrest at G1 phase and thus, inhibit G1/S transition and cell cycle progression. In addition, both compounds stimulate apoptotic death of breast cells significantly to reach 8.72%, and 17.28% respectively, compared to their control (0.55%). Apoptotic induction of breast cells was enhanced effectively through activation of caspase-3 by compound 8 using Elisa assay.