New arylpyrazoline-coumarins: Synthesis and anti-inflammatory activity

Design, synthesis, in vitro and in vivo biological evaluation of pterostilbene derivatives for anti-inflammation therapy

Pterostilbene (PST) is a naturally derived stilbene compound in grapes, blueberries, and other fruits. It is also a natural dietary compound with a wide range of biological activities such as antioxidant, anti-inflammatory, antitumor, and so on. Structural modifications based on the chemical scaffold of the pterostilbene skeleton are of great importance for drug discovery. In this study, pterostilbene skeletons were used to design novel anti-inflammatory compounds with high activity and low toxicity. A total of 30 new were found and synthesised, and their anti-inflammatory activity and safety were screened. Among them, compound E2 was the most active (against NO: IC50 = 0.7 μM) than celecoxib. Further studies showed that compound E2 exerted anti-inflammatory activity by blocking LPS-induced NF-κB/MAPK signalling pathway activation. In vivo experiments revealed that compound E2 had a good alleviating effect on acute colitis in mice. In conclusion, compound E2 may be a promising anti-inflammatory lead compound.

Characterization of the structure, anti-inflammatory activity and molecular docking of a neutral polysaccharide separated from American ginseng berries

AIM

American ginseng berries, grown in the aerial parts and harvested in August, are a potentially valuable material. The aim of the study was to analyze the specific polysaccharides in American ginseng berries, and to demonstrate the anti-inflammation effect through in vitro and in vivo experiments and molecular docking.

METHODS

After deproteinization and dialysis, the extracted crude polysaccharide was separated and purified. The structure of the specific isolated polysaccharide was investigated by Fourier Transform infrared spectroscopy (FT-IR), GC-MS and nuclear magnetic resonance (NMR), and anti-inflammatory activity was evaluated using in vitro and in vivo models (Raw 264.7 cells and zebrafish). Molecular docking was used to analyze the binding capacity and interaction with cyclooxygenase-2 (COX-2).

RESULTS

A novel neutral polysaccharide fraction (AGBP-A) was isolated from American ginseng berries. The structural analysis demonstrated that AGBP-A had a weight-average molecular weight (Mw) of 122,988 Da with a dispersity index (Mw/Mn) value of 1.59 and was composed of arabinose and galactose with a core structure containing →6)-Gal-(1→ residues as the backbone and a branching substitution at the C3 position. The side-chains comprised of α-L-Ara-(1→, α-L-Ara-(1→, →5)-α-L-Ara-(1→, β-D-Gal-(1→. The results showed that it significantly decreased pro-inflammatory cytokines in the cell model. In a zebrafish model, AGBP-A reduced the massive recruitment of neutrophils to the caudal lateral line neuromast, suggesting the relief of inflammation. Molecular docking was used to analyze the combined capacity and interaction with COX-2.

CONCLUSION

Our study indicated the potential efficacy of AGBP-A as a safe and valid natural anti-inflammatory component.

Synthesis, biofilm formation inhibitory, and inflammation inhibitory activities of new coumarin derivatives

Coumarins are heterocycles of great interest in the development of valuable active structures in chemistry and biological domains. The ability of coumarins to inhibit biofilm formation of Gram positive bacterium (Staphylococcus aureus), Gram negative bacterium (Escherichia coli) as well as the methicillin-resistant S. aureus (MRSA) has been previously described. In the present work, new hybrid coumarin-heterocycles have been synthesized via the reaction of coumarin-6-sulfonyl chloride and 6-aminocoumarin with different small heterocycle moieties. The biological efficacy of the new compounds was evaluated towards their ability to inhibit biofilm formation and their anti-inflammatory properties. The antimicrobial activities of the newly synthesized compounds were tested against Gram positive bacterium (S. aureus ATCC 6538), Gram negative bacterium (E. coli ATCC 25922), yeast (Candida albicans ATCC 10231) and the fungus (Aspergillus niger NRRL-A326). Compounds 4d, 4e, 4f, 6a and 9 showed significant MIC and MBC values against S. aureus, E. coli, C. albicans, and methicillin-resistant S. aureus (MRSA) with especial incidence on compound 9 which surpasses all the other compounds giving MIC and MBC values of (4.88 and 9.76 µg/mL for S. aureus), (78.13 and 312.5 µg/mL for E. coli), (9.77 and 78.13 µg/mL for C. albicans), and (39.06 and 76.7 µg/mL for MRSA), respectively. With reference to the antibiofilm activity, compound 9 exhibited potent antibiofilm activity with IC50 of 60, 133.32, and 19.67 µg/mL against S. aureus, E. coli, and MRSA, (respectively) considering the reference drug (neomycin). Out of all studied compounds, the anti-inflammatory results indicated that compound 4d effectively inhibited nitric oxide production in lipopolysaccharide-(LPS-) stimulated RAW264.7 macrophage cells, giving NO% inhibition of 70% compared to Sulindac (55.2%).

Design, Synthesis, Antifungal Activity, and 3D-QASR of Novel Oxime Ether-Containing Coumarin Derivatives as Potential Fungicides

Structural modification of natural products is an effective approach for improving antifungal activity and has, therefore, been used extensively in the development of new agrochemical products. In this work, a series of novel coumarin derivatives containing oxime ether structures were designed, synthesized, and evaluated for antifungal activity. Some of the designed compounds exhibited promising antifungal activities against tested fungi, and compounds 4a, 4c, 5a, and 6b had EC50 values equivalent to those of commercial fungicides. Compound 6b was the most promising candidate fungicide against Rhizoctonia solani (EC50 = 0.46 μg/mL). In vivo antifungal bioassays suggested that compounds 5a and 6b could serve as novel agricultural antifungals. Furthermore, microscopy demonstrated that compound 6b induced the sprawling growth of hyphae, distorted the outline of cell walls, and reduced mitochondrial numbers. Additionally, the effects of the substituent steric, electrostatic, hydrophobic, and hydrogen-bond fields were elucidated using an accurate and reliable three-dimensional quantitative structure-activity relationship (3D-QSAR) model. The results presented here will guide the discovery of potential novel fungicides for plant disease control in agriculture.

Design and synthesis of forsythin derivatives as anti-inflammatory agents for acute lung injury

Acute lung injury (ALI) is a clinically high mortality disease, which has not yet been effectively treated. The development of anti-ALI drugs is imminent. ALI can be effectively treated by inhibiting the inflammatory cascade and reducing the inflammatory response in the lung. Forsythia suspense is a common Chinese herbal medicine with significant anti-inflammatory activity. Using forsythin as the parent, 27 Forsythin derivatives were designed and synthesized, and the anti-AIL activity of these compounds was evaluated. Among them, compound B5 has the best activity to inhibit the release of IL-6, and the inhibition rate reaches 91.79% at 25 μM, which was 7.5 times that of the parent forsythin. In addition, most of the compounds have no significant cytotoxicity in vitro. Further studies showed that compound B5 had a concentration-dependent inhibitory effect on NO, IL-6 and TNF-α. And the IC50 values of compound B5 for NO and IL-6 are 10.88 μM and 4.93 μM, respectively. We also found that B5 could significantly inhibit the expression of some immune-related cytotoxic factors, including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In addition, B5 inhibits NF-κB/MAPK signaling pathway. In vivo experiments showed that B5 could alleviate lung inflammation in LPS-induced ALI mice and inhibit IL-6, TNF-α, COX-2 and iNOS. In summary, B5 has anti-inflammatory effects and alleviates ALI by regulating inflammatory mediators and inhibiting MAPK and NF-κB signaling pathways.

Design and synthesis of pterostilbene derivatives bearing triazole moiety that might treat DSS-induced colitis in mice through modulation of NF-κB/MAPK signaling pathways

In this study, a series of novel anti-inflammatory compounds with high activity and low toxicity were designed and synthesized based on the natural product pterostilbene skeleton. According to the strategy of pharmacophore combination, we introduced thiazole moiety into pterostilbene skeleton to design and synthesize a novel series of pterostilbene derivatives (a total of 41 compounds), and lipopolysaccharide (LPS)-treated RAW 264.7 cells were screened for anti-inflammatory activity and cytotoxicity. Among them, compound 8 was found to be the most active (against NO: IC50 = 0.6 μM) compared with pterostilbene and indomethacin. Anti-inflammatory mechanism studies revealed that compound 8 inhibited pro-inflammatory cytokines by blocking the NF-κB/MAPK signaling pathway in LPS-treated RAW 264.7 cells. In vivo experiments showed that compound 8 had a good relieving effect on DSS-induced acute colitis in mice, and also demonstrated a good safety in acute toxicity experiments. In conclusion, compound 8 may be a promising anti-inflammatory lead compound in the treatment of acute colitis.

7-Methoxy-4-methylcoumarin: Standard Molar Enthalpy of Formation Prediction in the Gas Phase Using Machine Learning and Its Comparison to the Experimental Data

Experimentally, the standard molar enthalpy of formation in the crystalline phase at 298.15 K, ΔfHm°(cr) for 7-methoxy-4-methylcoumarin (7M4MC) was calculated by traditional linear regression, which was obtained by combustion calorimetry. Similarly, the standard molar enthalpy of sublimation was determined through the standard molar enthalpy of fusion and by the standard molar enthalpy of vaporization, from differential scanning calorimetry and thermogravimetry, respectively; lately using these results, the standard molar enthalpy of formation in the gas phase was calculated at 298.15 K, ΔfHm°(g). In addition ML was used to predict the standard molar enthalpy of formation in the gas phase for the 7M4MC, constructing an experimental data set containing three kinds of functional groups: esters, coumarins, and aromatic compounds. The procedure was performed by using multiple linear regression algorithms and stochastic gradient descent with a R2 of 0.99. The obtained models were used to compare those predicted values versus experimental for coumarins, resulting in an average error rate of 9.0%. Likewise, four homodesmic reactions were proposed and predicted with the multiple linear regression algorithm of ML obtaining good results.

Syntheses of Minutuminolate and Related Coumarin Natural Products and Evaluation of Their TNF-α Inhibitory Activities

The concise syntheses of the coumarin natural product, minutuminolate (1), and its related natural products, 7-methoxy-8-(2-acetoxy-3-methyl-1-oxobut-2-enyl) coumarin (2) and muralatin I (3), were accomplished for the first time in 4-5 steps from the commercially available umbelliferone. The key step involves a palladium-catalyzed oxidative rearrangement reaction to assemble the α-acyloxyenone moiety in 1 and 2. The incorporation of this functionality enables the successful synthesis of coumarin 3 through an acidic hydrolysis reaction. The anti-inflammatory activities of the compounds were also evaluated against tumor necrosis factor-alpha production in lipopolysaccharides-stimulated RAW264.7 cells. Our developed synthetic route will facilitate the development of analogues and derivatives of 1-3 with potent anti-inflammatory activities.

Design, synthesis, and bioactivity evaluation of novel amide/sulfonamide derivatives as potential anti-inflammatory agents against acute lung injury and ulcerative colitis

The uneven regulation of inflammation is related to various diseases, making anti-inflammation a potential option for the development of novel therapies. In this study, we designed and synthesized a total of fifty-eight novel amide/sulfonamide derivatives based on our previously reported anti-inflammatory compounds. The anti-inflammatory activities of these compounds were evaluated upon LPS-stimulated J774A.1 cells. Compounds 11a, 11b, 11c, and 11d potently reduced the release of IL-6 and TNF-α, and decreased the mRNA level of cytokines in J774A.1 cells. The most active compound 11d with IC50 value of 0.61 μM for IL-6 inhibition, and 4.34 μM for TNF-α inhibition restored IκB α and inhibited the translocation of phosphorylated p65 into the nucleus. In vivo evaluation indicated that 11d improved LPS-induced ALI and alleviated DSS-induced ulcerative colitis in mice. In conclusion, these results suggested compound 11d can be a new lead structure for the development of anti-inflammatory drugs against ALI and ulcerative colitis.

Design, synthesis, and biological evaluation of new pyrimidine-5-carbonitrile derivatives as novel anti-cancer, dual EGFRWT/COX-2 inhibitors with docking studies

A novel series of pyrimidine-5-carbonitrile derivatives was designed, synthesized, then evaluated for their cytotoxic activity as novel anti-cancer with dual EGFRWT/COX-2 inhibitors. Two compounds 4e and 4f disclosed the highest activity against all NCI60 panel cell lines. They were most potent against Colo 205 (IC50 = 1.66, and 1.83 μM), Sequentially. The most potent two compounds disturbed cell cycle of Colo-205 cells by blocking the G1 phase, coupled with increased annexin-Vstained cells which indicated the increasing in percentage of apoptosis. In addition, 4e and 4f increase the concentration of caspase-3 by 10, and 8-fold compared to control, respectively. Moreover, the two candidate compounds were screened for cytotoxicity on normal epithelial colon cells; fortunately, they were found to be safe. Molecular docking study displayed that these compounds bound to the active site as EGFRWT/COX-2 inhibitors. Furthermore, 3D pharmacophore mapping disclosed many shared features between the most potent candidates 4e and 4f and the standard EGFRWT/COX-2 inhibitors; erlotinib, and celecoxib, respectively. Finally, the physicochemical parameter was calculated for the most potent novel anticancer candidates and the SwissAdme parameter showed that the newly synthesized compounds have good drug-likeness properties.

Design and Synthesis of Pyrimidine Amine Containing Isothiazole Coumarins for Fungal Control

Developing new fungicides is always crucial to protecting crops. A series of 4-(3,4-dichloroisothiazol-5-yl)-7-(2-((5-(5-pyrimidin-4-yl)amino)ethoxy)-8-methyl) coumarin derivatives were designed and synthesized by Williamson ether condensation and substitution reactions. Structure determinations were clarified by 1H NMR, 13C NMR, and HRMS, and compound 4h crystallized by the fusion method for further structural confirmation. The in vitro bioassay results showed that the target compounds displayed good fungicidal activity against Alternaria solani, Botrytis cinerea, Cercospora arachidicola, Fusarium graminearum, Physalospora piricola, Rhizoctonia solani, and Sclerotinia sclerotiorum. Among them, compounds 4b and 4d showed higher inhibitory activity against R. solani, with EC50 values of 11.3 and 13.7 μg/mL, respectively, and they were more active than the positive control diflumetorim with an EC50 value of 19.8 μg/mL. Molecular docking suggested that compound 4b and diflumetorim may have similar interactions with complex I NADH oxidoreductase. Density functional theory calculation and pesticide-likeness analysis studies gave a rational explanation of their fungicidal activity. These results indicated that compounds 4b and 4d deserved further optimization according to the principle of pesticide-likeness.

Design and synthesis of pseudo-rutaecarpines as potent anti-inflammatory agents via regulating MAPK/NF-κB pathways to relieve inflammation-induced acute liver injury in mice

Pseudo-natural products (PNPs) design strategy provides a great valuable entrance to effectively identify of novel bioactive scaffolds. In this report, novel pseudo-rutaecarpines were designed via the combination of several privileged structure units and 46 target compounds were synthesized. Most of them display moderate to potent inhibitory effect on LPS-induced NO production and low cytotoxicity in RAW264.7 macrophage. The results of the anti-inflammatory efficacy and action mechanism of compounds 7l and 8c indicated that they significantly reduced the release of IL-6, IL-1β and TNF-α. Further studies revealed that they can strongly inhibit the activation of NF-κB and MAPK signal pathways. The LPS-induced acute liver injury mice model studies not only confirmed their anti-inflammatory efficacy in vivo but also could effectively relieve the liver injury in mice. The results suggest that compounds 7l and 8c might serve as lead compounds to develop therapeutic drugs for treatment of inflammation.

Coumarin Based Fluorescent Probe for Detecting Heavy Metal Ions

Heavy metals such as Iron, Copper, and Zinc are micro-essential trace metal and involve animportant biological role, but it quickly turns toxic at exceeding the permissible limit, causing gastrointestinal irritation, liver, bone, and kidney damage, as well as disorders including Wilson's, Parkinson's, and Alzheimer's. It is important to detect the metal ions as well as their concentration quickly and affordable cost using organic probes. Among the organic probes,the coumarin fluorescent probe shows a very prominent candidate with heavy metal ions. Therefore, in the present review, we reviewed the very recent literature the identify the heavy metals using modified coumarin fluorescent probes. Readers will get information quickly about the method of preparation of modified coumarin core and their use as fluorescent probes with heavy metals using absorption and emission spectroscopic methods along with the probable mechanistic pathway of detection.

Anti-inflammatory ent-cleistanthane-type diterpenoids from Phyllanthus rheophyticus

A bioactivity-guided isolation from the aerial parts of Phyllanthus rheophyticus obtained 17 undescribed ent-cleistanthane-type diterpenoids, namely phyllarheophols A-Q, as well as 12 known analogs. Their structures were characterized by a combination of spectroscopic data interpretation, single-crystal X-ray diffraction and ECD analysis. The anti-inflammatory activities of these compounds were evaluated by measuring their inhibitory effects on NO production in LPS-stimulated RAW264.7 macrophages, and their preliminary structure-activity relationships were also discussed. Further study showed that promising compounds phyllarheophol D and phyacioid B significantly suppressed the expressions of cytokines and nitric oxide synthase through the NF-κB signaling pathway.

Discovery of pterostilbene analogs as novel NLRP3 inflammasome inhibitors for potential treatment of DSS-induced colitis in mice

The pterostilbene skeleton is a promising chemical scaffold that exerts anti-inflammatory, anti-depressant, and anti-tumor effects. In this study, we aim to reduce in vivo and in vitro toxicity of compound 32 (preliminary work) and maintain its biological activity. A series of novel pterostilbene derivatives (D1-D43) were designed and synthesized, and their anti-inflammatory activities were screened. All compounds were screened to evaluate their inhibitory effect on LPS/Nigericin-induced IL-1β production and pyroptosis. The structure-activity relationships was deduced, and finally 1-((E)-4-(2-ethoxyethoxy)styryl)-3,5-dimethoxy-2-((E)-2-nitrovinyl)benzene (D22) was found to be a low-toxic compound with most potent inhibitory efficacy (against IL-1β: IC₅₀ = 2.41 μM). Preliminary mechanism studies showed that compound D22 may affect the assembly of NLRP3 inflammasome by targeting NLRP3 protein, thereby inhibiting the activation of NLRP3 inflammasome. The in vivo anti-inflammatory activity indicated that compound D22 had significant therapeutic effects on DSS-induced mouse acute colitis models.

Therapeutic Effects of Coumarins with Different Substitution Patterns

The use of derivatives of natural and synthetic origin has gained attention because of their therapeutic effects against human diseases. Coumarins are one of the most common organic molecules and are used in medicine for their pharmacological and biological effects, such as anti-inflammatory, anticoagulant, antihypertensive, anticonvulsant, antioxidant, antimicrobial, and neuroprotective, among others. In addition, coumarin derivates can modulate signaling pathways that impact several cell processes. The objective of this review is to provide a narrative overview of the use of coumarin-derived compounds as potential therapeutic agents, as it has been shown that substituents on the basic core of coumarin have therapeutic effects against several human diseases and types of cancer, including breast, lung, colorectal, liver, and kidney cancer. In published studies, molecular docking has represented a powerful tool to evaluate and explain how these compounds selectively bind to proteins involved in various cellular processes, leading to specific interactions with a beneficial impact on human health. We also included studies that evaluated molecular interactions to identify potential biological targets with beneficial effects against human diseases.

Discovery of novel paeonol-based derivatives against skin inflammation in vitro and in vivo

T-LAK-cell-originated protein kinase (TOPK), a novel member of the mitogen-activated protein kinase family, is considered an effective therapeutic target for skin inflammation. In this study, a series (A − D) of paeonol derivatives was designed and synthesised using a fragment growing approach, and their anti-inflammatory activities against lipopolysaccharide (LPS)-induced nitric oxide production in RAW264.7 cells were tested. Among them, compound B12 yielded the best results (IC₅₀ = 2.14 μM) with low toxicity (IC₅₀ > 50 µM). Preliminary mechanistic studies indicated that this compound could inhibit the TOPK-p38/JNK signalling pathway and phosphorylate downstream related proteins. A murine psoriasis-like skin inflammation model was used to determine its therapeutic effect.

Coumarins Synthesis and Transformation via C–H Bond Activation—A Review

For several decades, coumarins have attracted considerable attention due to the fact of their application in diverse fields such as medical science and biomedical research as well as several industrial branches. Recently, many compounds containing the coumarin moiety have been intensively studied, mainly due to the fact of their biological activities such as antitumor, antioxidative, anti-HIV, vasorelaxant, antimicrobial, and anticancer. They are also widely used as fluorescent dyes and probes because of their great structural flexibility and large fluorescent quantum yields. For this reason, numerous attempts have been made to develop new and more practical methods for the synthesis of these compounds. This review aims at providing a comprehensive overview of coumarin synthesis methods by direct C–H bond activation in order to demonstrate the current state-of-the-art methods as well as the current limitations.

Microwave Assisted Synthesis of Novel Triazolyl Pyrazolyl Pyrazoline Substituted Coumarins and their Antimicrobial Activity

Background:

The 1,2,3-triazole, pyrazole and coumarin based derivatives have received much attention due to their wide coverage of biological properties. The present work describes the microwave synthesis of novel triazolyl pyrazolyl pyrazoline substituted coumarins. Structure of all the newly synthesized compounds are characterized by spectral analysis and screened for their in vitro antimicrobial activity by Broth dilution method.

Methods:

In synthetic method , the targets were prepared by reaction of various 3-{3-[3-(5-methyl-1-aryl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazol-4-yl]acryloyl} coumarins (coumarin chalcones) (3a-d) with hydrazine hydrate or aryl hydrazine(5a-c) in the presence of acetic/propionic acid under microwave irradiation.

Results:

The structures of all the synthesized compounds were established by IR, 1H-NMR, 13C-APT and selected mass spectral data. The target compounds were also screen for their in vitro antimicrobial efficiency against representative panel of pathogenic strains specifically Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis), Gram-negative bacteria (Escherichia coli, Salmonella typhi) and Fungi (Candida albicans, Aspergillus niger).

Conclusion:

In conclusion ,the target compounds were obtained by Microwave Irradiation (MWI) technique in good yield with short reaction time. Among all the synthesized compounds ,4c,4h,6a,6h and 6l were found to have significant activity against bacterial and fungal strains.

Recent Developments of Coumarin-based Hybrids in Drug Discovery

Coumarin scaffold is a highly significant O-heterocycle, namely benzopyran-2-ones, form an elite class of naturally occurring compounds that possess promising therapeutic perspectives. Based on its broad spectrum of biological activities, the privileged coumarin scaffold is applied to medicinal and pharmacological treatments by several rational design strategies and approaches. Structure-activity relationships of the coumarin-based hybrids with various bioactivity fragments revealed significant information toward the further development of highly potent and selective disorder therapeutic agents. The molecular docking studies between coumarins and critical therapeutic enzymes demonstrated mode of action by forming noncovalent interactions with more than one receptor, further rationally confirm information about structure-activity relationships. This review summarizes recent developments relating to coumarin-based hybrids with other pharmacophores aiming to numerous feasible therapeutic enzymatic targets to combat various therapeutic fields, including anticancer, antimicrobic, anti-Alzheimer, anti-inflammatory activities.

Pharmacological report of recently designed multifunctional coumarin and coumarin-heterocycle derivatives

Coumarin is a naturally available molecule and has been identified as a potent pharmacophore due to its pharmacological activity. Because of this, coumarin has been exploited synthetically to prepare a wide range of derivatives. In fact, most coumarin derivatives have been found to be less toxic, which is the most essential property for a drug molecule. Such molecules are being prepared for therapeutic use as broad-spectrum pharmacological agents. Microbial diseases including viral diseases have become very common and are responsible for many deaths worldwide. In particular, microbial drug resistance is a problem that needs to be tackled in an effective manner. Also, for Alzheimer's disease, which affects most elderly persons, no efficient chemotherapy exists. In addition, although diabetes, a metabolic syndrome, can be treated with many drugs, there is no complete cure. Thus, more potent antidiabetic agents are required for the management of diabetes. Likewise, for the treatment of a wide range of ailments caused by microbes, genetic factors, or lifestyle-related factors, an efficient drug regimen is needed. In view of this, coumarin derivatives are designed and evaluated. Here, coumarin derivatives that have been reported recently are compiled, classified and evaluated critically. This study briefly takes the structure-activity relationship into consideration and suggests the next suitable step. With a focus on the most potent molecules, the pharmacological activity of the evaluated molecules is described.

Discovery of Novel Pterostilbene-Based Derivatives as Potent and Orally Active NLRP3 Inflammasome Inhibitors with Inflammatory Activity for Colitis

Studies have shown that the abnormal activation of the NLRP3 inflammasome is involved in a variety of inflammatory-based diseases. In this study, a high content screening model targeting the activation of inflammasome was first established and pterostilbene was discovered as the active scaffold. Based on this finding, total of 50 pterostilbene derivatives were then designed and synthesized. Among them, compound 47 was found to be the best one for inhibiting cell pyroptosis [inhibitory rate (IR) = 73.09% at 10 μM], showing low toxicity and high efficiency [against interleukin-1β (IL-1β): half-maximal inhibitory concentration (IC50) = 0.56 μM]. Further studies showed that compound 47 affected the assembly of the NLRP3 inflammasomes by targeting NLRP3. The in vivo biological activity showed that this compound significantly alleviated dextran sodium sulfate (DSS)-induced colitis in mice. In general, our study provided a novel lead compound directly targeting the NLRP3 protein, which is worthy of further research and structural optimization.

Synthesis and evaluation of the anti-inflammatory activity of novel 8-quinolinesulfonamide derivatives as TLR4/MD-2 inhibitors with efficacy in adjuvant-induced arthritis

In this study, a series of 8-quinolinesulfonamidederivatives was synthesized, and their anti-inflammatory activity was evaluated. Among them, compound 3l was found to be the best anti-inflammatory agent, with IC50 values of 2.61 ± 0.39, 9.74 ± 0.85, and 12.71 ± 1.34 μM against NO, TNF-α and IL-1β production respectively. And 3l could significantly prevent lipopolysaccharide (LPS)-induced expression of inflammatory mediators (iNOS and COX-2). Molecule docking results showed that 3l could bind to the LPS binding site of toll-like receptor 4 (TLR4)/MD-2, and 3l was then identified as TLR4/MD-2 inhibitor by co-immunoprecipitation (co-IP) and cellular thermal shift assay (CTESA). Preliminary mechanism studies indicated that 3l could prevent TLR4 from being activated by disrupting TLR4/MD-2 heterodimerization and TLR4 homodimerization, thereby blocking the activation of the NF-κB/MAPK signaling pathway. Furthermore, observation of rat foot swelling, joint pathology and serum inflammatory cytokine levels proved that compound 3l had a significant therapeutic effect on adjuvant-induced arthritis (AIA) in rats in vivo. These results indicated that compound 3l is a potential anti-inflammatory agent, from which more effective anti-inflammatory drugs could be developed.

Discovery of novel 2H-chromene-3-carbonyl derivatives as selective estrogen receptor degraders (SERDs): Design, synthesis and biological evaluation

Selective estrogen receptor degraders (SERDs) not only block ERα activity but degrade this receptor at the same time and are effective in relapsed ERα positive breast cancer patients who have accepted other endocrine therapies. Herein, through scaffold hopping of coumarin skeleton, a series of 2H-chromene-3-carbonyl-based SERDs with phenyl acrylic acid group as the side chain were designed and synthesized. Compound XH04 containing 7-hydroxy-2H-chromene-3-carbonyl skeleton exhibited the most potent activities in 2D (IC₅₀ = 0.8 μM) and 3D cells culture models (MCF-7) and had the best ERα binding affinity as well. Furthermore, the significant antiestrogen property of compound XH04 was confirmed by inhibiting the expression of progesterone receptor (PgR) mRNA in MCF-7 cells. On the other hand, the outgoing ERα degradation property of compound XH04 was qualitatively and quantificationally verified by immunofluorescence analysis and Western blot assay in MCF-7 cells. Besides, compound XH04 repressed the expression level of Ki67 in MCF-7 cells and induced the apoptosis increase of this tumor cells in a dose-dependent manner like approved-SERD fulvestrant (2), while compound XH04 exhibited better preliminary pharmacokinetics in human and rat liver microsomes in vitro and a lower LogD_7.4 value than fulvestrant. And further molecular docking study revealed that compound XH04 possessed a proverbial and typical binding model with ERα like other reported SERD. All these results confirmed that 7-hydroxy-2H-chromene-3-carbonyl structure could be a feasible skeleton for design of ERα antagonists including SERDs and compound XH04 is a promising candidate for further development of ERα + breast cancer therapy agents.

Design and synthesis of 7-O-1,2,3-triazole hesperetin derivatives to relieve inflammation of acute liver injury in mice

Based on the previous research results of our research group, to further improve the anti-inflammatory activity of hesperetin, we substituted triazole at the 7-OH branch of hesperetin. We also evaluated the anti-inflammatory activity of 39 new hesperetin derivatives. All compounds showed inhibitory effects on nitric oxide (NO) and inflammatory factors in lipopolysaccharide-induced RAW264.7 cells. Compound d5 showed a strong inhibitory effect on NO (half maximal inhibitory concentration = 2.34 ± 0.7 μM) and tumor necrosis factor-α, interleukin (IL)-1β, and (IL-6). Structure-activity relationships indicate that 7-O-triazole is buried in a medium-sized hydrophobic cavity that binds to the receptor. Compound d5 can also reduce the reactive oxygen species production and significantly inhibit the expression of inducible NO synthase and cyclooxygenase-2 through the nuclear factor-κB signaling pathway. In vivo results indicate that d5 can reduce liver inflammation in mice with acute liver injury (ALI) induced by CCI₄. In conclusion, d5 may be a candidate drug for treating inflammation associated with ALI.

Novel Fluorinated 7-Hydroxycoumarin Derivatives Containing an Oxime Ether Moiety: Design, Synthesis, Crystal Structure and Biological Evaluation

A series of fluorinated 7-hydroxycoumarin derivatives containing an oxime ether moiety have been designed, synthesized and evaluated for their antifungal activity. All the target compounds were determined by ¹H-NMR, ¹³C-NMR, FTIR and HR-MS spectra. The single-crystal structures of compounds 4e, 4h, 5h and 6c were further confirmed using X-ray diffraction. The antifungal activities against Botrytis cinerea (B. cinerea), Alternariasolani (A. solani), Gibberella zeae (G. zeae), Rhizoctorzia solani (R. solani), Colletotrichum orbiculare (C. orbiculare) and Alternaria alternata (A. alternata) were evaluated in vitro. The preliminary bioassays showed that some of the designed compounds displayed the promising antifungal activities against the above tested fungi. Strikingly, the target compounds 5f and 6h exhibited outstanding antifungal activity against B. cinerea at 100 μg/mL, with the corresponding inhibition rates reached 90.1 and 85.0%, which were better than the positive control Osthole (83.6%) and Azoxystrobin (46.5%). The compound 5f was identified as the promising fungicide candidate against B. cinerea with the EC₅₀ values of 5.75 μg/mL, which was obviously better than Osthole (33.20 μg/mL) and Azoxystrobin (64.95 μg/mL). Meanwhile, the compound 5f showed remarkable antifungal activities against R. solani with the EC₅₀ values of 28.96 μg/mL, which was better than Osthole (67.18 μg/mL) and equivalent to Azoxystrobin (21.34 μg/mL). The results provide a significant foundation for the search of novel fluorinated 7-hydroxycoumarin derivatives with good antifungal activity.

N-Aryl iminochromenes inhibit cyclooxygenase enzymes via π–π stacking interactions and present a novel class of anti-inflammatory drugs

Cyclooxygenase enzymes (COX1/2) have been widely studied and noted for their role in the biosynthesis of inflammation-induced proteins, prostaglandins and thromboxane. Multiple anti-inflammatory drugs have been developed to target these two enzymes, but most of them appeared to have notable adverse effects, especially on the cardiovascular system and lower gastrointestinal tract, suggesting an urgent need for new potent anti-inflammatory drugs. In this study, we screened twenty-two previously synthesized N-aryl iminochromenes (NAIs) for their anti-inflammatory activity by performing COX-1/2 inhibitory assays. Five compounds (1, 10, 14, 15, and 20) that gave the best in vitro anti-inflammatory results were subjected to an in vivo anti-inflammatory assay using the formalin-induced hind rat paw oedema method, followed by in silico studies using indomethacin and celecoxib as standard drugs. Among them, compound 10 stood out as the best candidate, and the percentage reduction in paw oedema at the dose of 20 mg kg⁻¹ body weight was found to be substantially higher with compound 10 than that with indomethacin. This is mostly due to the excellent suitability of the chromene-phenyl scaffold with a highly concentrated area of aromatic residues, which produced good π–π stacking interactions. Taken together, this study strongly suggests compound 10 as a potential candidate for anti-inflammatory drug research.

Screening of N-aryl iminochromenes for their anti-inflammatory activities by performing in vitro, in vivo, and in silico studies.

Evaluating the In Vitro Activity of Depsidones from Usnea subfloridana Stirton as Key Enzymes Involved in Inflammation and Gout

Background: Traditionally, Usnea genus has significant uses in the treatment of swelling and tumors in Africa and Asia. The aim of the present study was to investigate the chemical constituents present in the acetone extract (AE) of Usnea subfloridana Stirton and also to evaluate their anti-inflammatory and anti-gout effects. Methods: Isolation and characterization of secondary metabolites from AE were evaluated by chromatography and spectral studies. Anti-inflammatory activities were assessed through cyclooxygenase (COX1 and COX2) and 5-lipooxygenase (5-LOX) enzyme inhibition assays, while anti-gout effects were evaluated by xanthine oxidase (XO) inhibition assay. Results: The existence of five known depsidones, identified as galbinic acid (1), conprotocetraricacid (2), constictic acid (3), salazinic acid (4), and lobaric acid (5), were exposed by chemical investigation of AE and confirmed by spectral data. Using in vitro enzyme inhibition assays, it was noticed that all the isolates showed dose-dependent activity against all the tested enzymes. Mainly, compounds 2 and 5 showed better inhibition efficiency on COX2 enzyme with the IC50of 7.17±1.07 and 7.01±0.94 nM, respectively, than the reference drug indomethacin (7.3±0.65nM). Furthermore, all isolates exhibited potent inhibition effects on the XO enzyme. Conclusion: The results indicated that U. subfloridana can be a favorable natural source for thetreatment of inflammation and gout. Compounds 2 and 5 were responsible for these biologicalactions by regulating pro-inflammatory enzymes, namely COXs, 5-LOX, and XO.

2D-QSAR and docking study of a series of coumarin derivatives as inhibitors of CDK (anticancer activity) with an application of the molecular docking method

Quantitative Structure Activity Relationship (QSAR) analysis techniques are tools largely utilized in many research fields, including drug discovery processes. In this work electronic descriptors are calculated with the Gaussian 03W software using the DFT method with the BecKe 3-parameters exchange functional and Lee-Yang-Parr correlation functional, with Kohn and Sham orbitals (KS) developed on a Gaussian Basis of type 6-31G (d), in combination with five Lipinski parameters that have been calculated with ChemOffice software, in order to develop a statistically verified 2D-QSAR model able to predict the biological activity of new molecules belonging to the same range of coumarins rather than chemical synthesis and biological evaluations that require more time and resources. Two QSAR models against both MCF-7 and HepG-2 cell lines are obtained using the multiple linear regression method. The predictive power of these models has been confirmed by internal and external validation. The Leverage method was used to determine the domain of applicability of the 2D-QSAR models developed. The results indicate that the best QSAR model is the one that links the 2D descriptors with the CDK inhibitory activity of the cell line (HepG-2) R² = 0.748, R²cv = 0.618, MSE = 0.03 for the learning series and R² = 0.73, MSE = 0.18 for the test series. This model implies that coumarin inhibitory activity is strongly related to dipole moment and the number of hydrogen bond donors. The results obtained suggest the importance of studying structure-activity relationships as a principal axis in drug design. The docking procedure using AutoDOCK Tools was also used to understand the mechanisms of molecular interactions and consequently, to develop new inhibitors.

Novel phthalide derivatives: Synthesis and anti-inflammatory activity in vitro and in vivo

Phthalide is a promising chemical scaffold and has been proved to show potent anti-inflammatory efficacy. In this study, three series, total of 31 novel phthalide derivatives were designed and synthesized, their anti-inflammatory activities were screened in vitro and in vivo. The anti-inflammatory activity of all the compounds were screened on LPS induced NO production to evaluating their inhibitory effects. Structure-activity relationship has been concluded, and finally 3-((4-((4-fluorobenzyl)oxy)phenyl)(hydroxy)methyl)-5,7-dimethoxyisobenzofuran-1 (3H)-one (compound 9o) was found to be the active one with low toxicity, which showed 95.23% inhibitory rate at 10 μM with IC₅₀ value of 0.76 μM against LPS-induced NO over expression. Preliminary mechanism studies indicated that compound 9o activated Nrf2/HO-1 signaling pathway via accumulation ROS and blocks the NF-κB/MAPK signaling pathway. The in vivo anti-inflammatory activity shown that compound 9o had obvious therapeutic effect against the adjuvant-induced rat arthritis model.

Recent advancements in the development of bioactive pyrazoline derivatives

Pyrazolines remain privileged heterocycles in drug discovery. 2-Pyrazoline scaffold has been proven as a ubiquitous motif which is present in a number of pharmacologically important drug molecules such as antipyrine, ramifenazone, ibipinabant, axitinib etc. They have been widely explored by the scientific community and are reported to possess wide spectrum of biological activities. For combating unprecedented diseases and worldwide increasing drug resistance, 2-pyrazoline has been tackled as a fascinating pharmacophore to generate new molecules with improved potency and lesser toxicity along with desired pharmacokinetic profile. This review aims to summarizes various recent advancements in the medicinal chemistry of pyrazoline based compounds with the following objectives: (1) To represent inclusive data on pyrazoline based marketed drugs as well as therapeutic candidates undergoing preclinical and clinical developments; (2) To discuss recent advances in the medicinal chemistry of pyrazoline derivatives with their numerous biological significances for the eradication of various diseases; (3) Summarizes structure-activity relationships (SAR) including in silico and mechanistic studies to afford ideas for the design and development of novel compounds with desired therapeutic implications.

Overview on developed synthesis procedures of coumarin heterocycles

Considering highly valuable biological and pharmaceutical properties of coumarins, the synthesis of these heterocycles has been considered for many organic and pharmaceutical chemists. This review includes the recent research in synthesis methods of coumarin systems, investigating their biological properties and describing the literature reports for the period of 2016 to the middle of 2020. In this review, we have classified the contents based on co-groups of coumarin ring. These reported methods are carried out in the classical and non-classical conditions particularly under green condition such as using green solvent, catalyst and other procedures.

Synthesis and anti-inflammatory activity of 2-oxo-2H-chromenyl and 2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates

Cycloaddition reaction of 4-chloro-2-oxo-2H-chromene-3-carbaldehydes (3a-g) and 4-chloro-2H-chromene-3-carbaldehydes (7a-h) with activated alkynes (4a-b) provided the 2-oxo-2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates (5a-n) and 2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates (8a-p). All the prepared compounds were screened for anti-inflammatory activity. In vitro anti-inflammatory activity data demonstrated that the compounds 5g, 5i, 5k-l and 8f are effective among the tested compounds against TNF-α (1.108 ± 0.002, 0.423 ± 0.022, 0.047 ± 0.001, 0.070 ± 0.002 and 0.142 ± 0.001 µM) in comparison with standard compound Prednisolone (0.033 ± 0.002 µM). Based on in vitro results, three compounds (5i, 5k and 8f) have been selected for in vivo experiments and these compounds are identified as better compounds with respect to anti-inflammatory activity in LPS induced mice model. Compound 5i was identified as potent and showed significant reduction in TNF-α and IL-6.

Coumarins in Food and Methods of Their Determination

Coumarin is a natural product with aromatic and fragrant characteristics, widespread in the entire plant kingdom. It is found in different plant sources such as vegetables, spices, fruits, and medicinal plants including all parts of the plants-fruits, roots, stems and leaves. Coumarin is found in high concentrations in certain types of cinnamon, which is one of the most frequent sources for human exposure to this substance. However, human exposure to coumarin has not been strictly determined, since there are no systematic measurements of consumption of cinnamon-containing foods. The addition of pure coumarin to foods is not allowed, since large amounts of coumarin can be hepatotoxic. However, according to the new European aroma law, coumarin may be present in foods only naturally or as a flavoring obtained from natural raw materials (as is the case with cinnamon). In this paper, the overview of the current European regulations on coumarin levels in food is presented, along with the most common coumarin food sources, with a special emphasis on cinnamon-containing food. Human exposure to coumarins in food is also reviewed, as well as the methods for determination and separation of coumarin and its derivatives in food.

Design, Synthesis and Evaluation of 3-Substituted Coumarin Derivatives as Anti-inflammatory Agents

Coumarin moiety has garnered momentous attention especially in the design of compounds with significant biological activities. In this work, a series of 3-substituted coumarin derivatives 6a-6l were synthesized and fully characterized. Most of the compounds could obviously inhibit the activity of cyclooxygenase-1 (COX-1) at the concentration of 10 µM. Besides, 6h and 6l exhibited highest inhibitory effects against COX-2 with inhibition rates of 33.48 and 35.71%, respectively. Detailed structure-activity relationships (SARs) were also discussed. In vivo studies, 6b, 6i and 6l could remarkably repress the xylene-induced ear swelling in mice at the dose of 20 mg/kg. Especially, 6l seemed to be the most effective compound at the dose of 10 mg/kg, displaying favorable anti-inflammatory activity comparable to indomethacin. All of these findings suggested that 6l might be utilized as a candidate for the treatment of inflammatory diseases.