Design, synthesis, biological evaluation and docking study of novel indole-2-amide as anti-inflammatory agents with dual inhibition of COX and 5-LOX

Eucalyptol attenuates indomethacin-induced gastric ulcers in rats by modulating the ICAM-1, eNOS and COX/LOX pathways: Insights from in silico, in vitro and in vivo approaches

In order to evaluate anti-inflammatory role of eucalyptol (100, 200, and 400 mg/kg orally), inflammation was induced in rats using 0.1 ml of histamine and 0.1 ml of formaldehyde. Furthermore, in vivo gastroprotective potential of eucalyptol (100, 200 and 400 mg/kg) was determined via the intraperitoneal injection of 25 mg/kg indomethacin as an ulcerative agent and omeprazole (30 mg/kg) orally as a standard. Estimation of biochemical (PGE2, ICAM-1, COX-I, COX-II, eNOS and 5-LOX) and oxidative stress (SOD, CAT, GSH, and MDA) markers were carried out in gastric tissues using ELISA. The morphological and histopathological features of the gastric tissues were studied. In vitro, eucalyptol stabilized red blood cell membranes and inhibited protein denaturation, with the maximum effect observed at a concentration of 6400 μg/mL. Eucalyptol significantly reduced rat paw edema in histamine- and formaldehyde-induced inflammation models. It increased gastric PGE2, COX-I and eNOS levels, and decreased COX-II, 5-LOX and ICAM-1. Eucalyptol reduced ulcer indices and improved histopathological changes. Eucalyptol also increased antioxidants levels with decreased MDA levels in isolated rat stomach tissues. Therefore, eucalyptol shows gastroprotective effects against histamine- and formaldehyde induced inflammation and indomethacin-induced gastric ulcers through the modulation of the COX/LOX, ICAM-1, eNOS pathways and oxidative stress biomarkers.

Phytochemical analysis and biological study on Sinapis alba L. seeds extract incorporated with metal nanoparticles, in vitro approach

White mustard (Sinapis alba L.) seeds are the most commonly used mustard species in herbal medicine to treat a wide range of inflammatory disorders. Due to its increased bioavailability and lower toxicity, the green biosynthesis of metal nanoparticles (M-NPs) utilizing plant extract as a capping agent has been demonstrated over a number of years. Thus, the current study sought to examine the in vitro biological activity of copper oxide nanoparticles  (CuO-NPs) and selenium nanoparticles (Se-NPs) that were biosynthesized using aqueous, methanolic, and petroleum ether extracts from S. alba seeds. Phytochemical and in vitro biological activities (antioxidant, scavenging, anti-diabetic, anti-acetylcholinesterase, anti-arthritic, anti-inflammatory, and cytotoxic activities) were assayed in all prepared extracts before and after being used for the biosynthesis of the M-NPs. It was found that the total methanolic extract possessed the highest biological activities compared to other native extracts. The LC-ESI-MS/MS analysis of secondary metabolites showed that the total methanolic extract contained 7 phenolic acids and 9 flavonoid aglycones. This helped find the active ingredients. We characterized 8 phenolic acid derivatives, 7 flavonoid glycosides, 4 aliphatic glucosinolates, and 3 aromatic aryl glucosinolates in the aqueous extract. Furthermore, the methanolic extract contains the highest concentrations of total polyphenols, condensed tannins, and total flavonoid compounds. The biosynthesized Se-NPs using methanolic extract showed higher in vitro biological activities compared to those of the biosynthesized CuO-NPs. The median lethal dose (LD50) showed that the biosynthesized Se-NPs using the studied extracts appeared safer compared to those of the biosynthesized CuO-NPs. The findings of this study concluded that the total methanolic extract is the most suitable bioresource for biosynthesizing Se-NPs through green nanotechnology, with higher biological efficiency in relation to its metabolite fingerprint.

Ligustrazine as a multitarget scaffold in drug design and discovery

Ligustrazine has gained significant attention for its unique structural role in natural medicinal chemistry and its potential in drug discovery and development. The ligustrazine structure has been recognized as a clinical drug for treating cardiovascular and cerebrovascular diseases, especially in the design of neuroprotective agents. Recently, ligustrazine-based anti-tumor agents have also been reported. This knowledge can undoubtedly be applied to design multi-target-directed ligands, a highly relevant strategy for the complex pathological conditions of multifactorial diseases. In this review, we first discuss the biological properties and clinical applications of ligustrazine, then focus on the rational design of ligustrazine-based multifunctional ligands.

Investigations of In Vitro Anti-Acetylcholinesterase, Anti-Diabetic, Anti-Inflammatory, and Anti-Cancer Efficacy of Garden Cress (Lepidium sativum Linn.) Seed Extracts, as Well as In Vivo Biochemical and Hematological Assays

Background/Objectives: The current research was designed to quantify the active phyto-constituents and investigate the in vitro biological efficiency of different garden cress (Lepidium sativum Linn.) seed extracts against chronic diseases as well as the in vivo toxicities that may be induced in mice upon the administration of each extract at both studied therapeutic doses. Methods: The in vitro biological efficiency of different L. sativum extracts, such as methanolic, aqueous, acetone, and ethyl acetate extracts, was assessed. The inhibition percentage (%) and the median inhibitory concentration (IC50) values of different L. sativum extracts were estimated against acetylcholinesterase enzyme, diabetes mellitus (α-amylase and α-glucosidase enzymes), and inflammation (cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and 5-lipoxygenase (5-LOX) enzymes). Additionally, the median inhibitory concentration (IC50) values of different L. sativum extracts against HepG-2, Caco-2, and A549 cells were assessed using 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Moreover, the toxicities that might be induced in mice at hematological (using an automatic blood analyzer) and biochemical levels were evaluated. Results: It was found that the methanolic L. sativum extract possessed the highest in vitro biological activities compared to the other studied extracts. The inhibition percentage values of the methanolic extract were 51.34, 54.35, 44.10, 43.48, and 40.78% against acetylcholinesterase, α-amylase, α-glucosidase, protein denaturation, and proteinase enzymes, respectively. The methanolic extract also exhibited an inhibitory effect against the COX-1 (55.05%), COX-2 (57.30%), and 5-LOX (50.15%) enzymes. Additionally, the methanolic extract possesses the highest cytotoxic activity against HepG-2, Caco-2, and A549 cells, with IC50 values of 52.27, 40.73, and 37.95 μg/mL, respectively. The median lethal doses (LD50) showed that the methanolic extract was safer when administered orally, followed by aqueous and acetone, then ethyl acetate extract. It was found that methanolic, aqueous, and acetone extracts showed no alterations when administered orally at two studied doses (1/10 and 1/20 of LD50) compared to the control. Conclusions: This study concluded that the methanolic extract possessed the highest in vitro biological activities and was safer than the other studied extracts, followed by aqueous, acetone, and then ethyl acetate extract. In the future, the in vivo biological efficacy of the methanolic L. sativum extract will be evaluated, as well as an elucidation of its mechanism against chronic diseases.

In Vitro Enzymatic and Computational Assessments of Pyrazole-Isatin and Pyrazole-Indole Conjugates as Anti-Diabetic, Anti-Arthritic, and Anti-Inflammatory Agents

Background/Objectives: Recently, the prevalence of diseases such as diabetes, arthritis, and inflammatory diseases, along with their complications, has become a significant health problem. This is in addition to the various biomedical applications of pyrazole, isatin, and indole derivatives. Accordingly, cooperation will continue between chemistry scientists, pharmaceutical scientists, and human doctors to produce hybrid compounds from pyrazole with isatin or indole possessing biological activities as anti-diabetic, anti-arthritic, and anti-inflammatory agents. Methods: The two series of pyrazole-isatin conjugates 12a-h and pyrazole-indole conjugates 14a-d were prepared from our previous works via the direct reaction of 5-amino-pyrazoles 10a-d with N-alkyl isatin 11a,b, and 1H-indole-3-carbaldehyde (13), respectively, using the previously reported procedure. The potential biological activities of 12a-h and 14a-d as anti-diabetic, anti-arthritic, and anti-inflammatory agents were assessed through estimated inhibition percentage (%) and the median inhibitory concentrations (IC50) using methods described in the literature. Further, the computational assessments of 12a-h and 14a-d such as toxic doses (the median lethal dose, LD50), toxicity classes, drug-likeness model scores (DLMS), molecular lipophilicity potential (MLP) maps, polar surface area (PSA) maps, and topological polar surface area (TPSA) values were predicted using available free websites. Results: The in vitro enzymatic assessment results showed that pyrazole-indole conjugate 14b possesses powerful activities against (i) α-amylase (% = 65.74 ± 0.23, IC50 = 4.21 ± 0.03 µg/mL) and α-glucosidase (% = 55.49 ± 0.23, IC50 = 2.76 ± 0.01 µg/mL); (ii) the protein denaturation enzyme (% = 49.30 ± 0.17) and against the proteinase enzyme (% = 46.55 ± 0.17) with an IC50 value of 6.77 ± 0.01 µg/mL; (iii) the COX-1, COX-2, and 5-LOX enzymes with an IC50 of 5.44 ± 0.03, 5.37 ± 0.04, and 7.52 ± 0.04, respectively, which is almost close to the IC50 of the indomethacin and zileuton drugs. Also, the computational assessment results showed (i) the conjugate 14b possesses lipophilic surface properties thus can cross cell membranes, and is effective for treatment; (ii) all the conjugates possess a TPSA value of more than 140 Å2 thus possess good intestinal absorption. Conclusions: The two series of pyrazole-isatin conjugates 12a-h and pyrazole-indole conjugates 14a-d were synthesized from our previous works. The results of these in vitro enzymatic and computational assessments concluded that the pyrazole-indole conjugate 14b possesses powerful activities against various studied enzymes and possesses good computational results. In the future, our research team will present in vitro, in vivo biological, and computational assessments to hopefully obtain effectual agents such as anti-diabetic, anti-arthritic, and anti-inflammatory.

Assessment of the In Vitro Biological Activities of Schiff Base-Synthesized Copper Oxide Nanoparticles as an Anti-Diabetic, Anti-Alzheimer, and Anti-Cancer Agent

Background/Objectives: Numerous diseases such as diabetes, Alzheimer's disease, and cancer have spread in the whole world, especially in the Arab world. Also, various applications of Schiff-base functionalized nanoparticles and copper oxide nanoparticles (CuO-NPs) such as therapeutic applications have been discovered. Thus, the current research highlights (i) the synthesis of copper oxide nanoparticles (CuO-NPs) produced with a Schiff base (SB) serving as a capping agent during their synthesis and (ii) assessment of the in vitro biological activities of Schiff base-synthesized copper oxide nanoparticles (SB-CuO-NPs) and a Schiff base (SB). Methods: SB-CuO-NPs were characterized using ultraviolet-visible (UV-Vis) spectroscopy, zeta potential, DLS analysis, and transmission electron microscope (TEM). It also focuses on assessing the in vitro biological applications and activities, including antioxidant, scavenging, anti-diabetic, anti-Alzheimer, anti-arthritic, anti-inflammatory, cytotoxic activities, and enzymes inhibitory potential, of Schiff base-synthesized copper oxide nanoparticles (SB-CuO-NPs) and a Schiff base (SB) using methods described in the literature. Results: The results of the biological activities of the SB-CuO-NPs were compared with those of the SB. The SB-CuO-NPs demonstrated superior in vitro biological activities when compared to the SB from which they were produced. Conclusions: The results of this investigation concluded that the CuO-NPs, synthesized with the SB serving as an alternative capping agent, exhibited enhanced biological efficacy relative to the original SB. In the future, the biological efficiency of SB-CuO-NPs against diabetes, Alzheimer's, and cancer diseases will be assessed in experimental animals (in vivo).

Indoles as promising Therapeutics: A review of recent drug discovery efforts

Indole, a fundamental heterocyclic core, has emerged as a cornerstone in the medicinal chemistry due to its diverse biological activities and structural versatility. This aromatic compound, present in natural as well as synthetic compounds, offers a versatile platform for the drug discovery. By strategically incorporating functional groups or pharmacophores, researchers can tailor indole-derivatives to target a wide range of diseases. This review delves into the multifaceted applications of indole derivatives, highlighting their potential as therapeutic agents for cancer, diabetes, depression, Alzheimer's diseases, Parkinson's disease, etc. emphasizing how indole derivatives can enhance potency and selectivity. By understanding the structure-activity relationship of indole compounds, scientists can develop innovative drug candidates with improved therapeutic profiles. The review highlights the diverse nature of indole-based derivatives along with the structure-activity relationshipThe current review comprehensively covers the advancements and developments in the field over the past seven years, specifically from 2017 to 2024. This timeframe was selected to provide an up-to-date and thorough analysis of recent progress, capturing significant trends, breakthroughs, and emerging insights within the domain. By focusing on this period, the review ensures relevance and highlights the evolving landscape of research, offering a detailed synthesis of key findings and their implications for future studies.

β-Citronellol: a potential anti-inflammatory and gastro-protective agent-mechanistic insights into its modulatory effects on COX-II, 5-LOX, eNOS, and ICAM-1 pathways through in vitro, in vivo, in silico, and network pharmacology studies

BACKGROUND

The current study aimed to evaluate the anti-inflammatory, anti-oxidant, and pronounced gastro-protective activities of β- Citronellol using in vitro, in vivo assays and in silico approaches.

METHODS

In vitro assays, denaturation of bovine serum albumin, egg protein, and human Red Blood Cells (RBCs) membrane stabilization were performed, using Piroxicam as standard. For in vivo assessment, Histamine (0.1 ml from 1% w/v) and Formaldehyde (0.1 ml from 2% v/v) were used to mediate inflammation. In silico molecular docking and network pharmacology were employed to probe the possible target genes mediating gastroprotective effect of β-Citronellol at 25, 50, and 100 mg/kg, using indomethacin-induced (25 mg/kg i.p) gastric ulcer in rats. Moreover, Gastric tissues were evaluated for morphological, histopathological, and bio-chemical analysis of PGE2, COX-I, COX-II, 5-LOX, eNOS, ICAM-1, oxygen-free radical scavengers (SOD, CAT), and oxidative stress marker (MDA).

RESULTS

β-Citronellol prevented denaturation of proteins and RBCs membrane stabilization with maximum effect observed at 6,400 µg/mL. Citronellol decreased rat's paw edema. Network pharmacology and docking studies revealed gastro-protective potential of Citronellol possibly mediated through arachidonic acid pathways by targeting COX-I, COX-II, PGE2, and 5-LOX. Citronellol reduced the ulcer indices, and histopathological changes. Further, β-Citronellol (50 and 100 mg/kg) increased gastric PGE2, COX-1, and eNOS; while suppressing COX-2, 5-LOX and ICAM-1. Citronellol markedly enhanced the oxidative balance in isolated rat stomach tissues.

CONCLUSIONS

The anti-inflammatory, anti-oxidant, and gastro-protective effects of β-Citronellol against indomethacin-induced gastric ulcer model in rats through mediating COX-I, COX-II, PGE2, 5-LOX, eNOS, and ICAM-1 inflammatory markers.

Indole-based COX-2 inhibitors: A decade of advances in inflammation, cancer, and Alzheimer's therapy

Cyclooxygenase-2 (COX-2), a key enzyme in the cyclooxygenase family, is pivotal in producing pro-inflammatory prostaglandins, driving chronic inflammation and related disorders. Targeting COX-2 with selective inhibitors can mitigate these conditions while avoiding the gastrointestinal and hepatotoxic/nephrotoxic side effects of traditional NSAIDs. However, the selectivity towards COX-2 inhibition has been associated with cardiovascular risks, necessitating the discovery of novel molecular scaffolds avoiding CVS side effects. This review focuses on advancements in Indole-based COX-2 inhibitors from 2013 to 2024, emphasizing their potential in treating inflammation, cancer, and Alzheimer's disease. The Indole scaffold, known for its versatility, allows for comprehensive structure-activity relationship (SAR) analysis, facilitating the development of molecules with enhanced selectivity and potency. Molecules having different substituents attached to the Indole scaffold supported by molecular modeling data, is explored in detail. This review provides an concise overview of the pharmacophore profiles of Indole-based chemotherapeutics, contributing to the development of advanced strategies for selective COX-2 inhibition and addressing the challenges and opportunities in the field.

Design, synthesis, and anti-inflammatory activity of indole-2-formamide benzimidazole[2,1-b]thiazole derivatives

Molecular hybridization is a widely employed technique in medicinal chemistry for drug modification, aiming to enhance pharmacological activity and minimize side effects. The combination of an indole ring and imidazole[2,1-b]thiazole has shown promising potential as a group that exhibits potent anti-inflammatory effects. In this study, we designed and synthesized a series of derivatives comprising indole-2-formamide benzimidazole[2,1-b]thiazole to evaluate their impact on LPS-induced production of pro-inflammatory cytokines NO, IL-6, and TNF-α release, as well as iron death in RAW264.7 cells. The findings revealed that most compounds effectively inhibited LPS-induced production of pro-inflammatory cytokines NO, IL-6, and TNF-α release in RAW264.7 cells. Compound 13b exhibited the most potent anti-inflammatory activity among the tested compounds. The results of the cytotoxicity assay indicated that compound 13b was nontoxic. Additionally, compound 13b was found to elevate the levels of ROS, MDA, and Fe2+, while reducing GSH content, thereby facilitating the iron death process. Consequently, compound 13b showed promise for future development as an anti-inflammatory drug.

Insight on novel oxindole conjugates adopting different anti-inflammatory investigations and quantitative evaluation

Background: A dual COX/5-LOX strategy was adopted to develop new oxindole derivatives with superior anti-inflammatory activity. Methods: Three series of oxindoles - esters 4a-p, 6a-l and imines 7a-o - were synthesized and evaluated for their anti-inflammatory and analgesic activities. Molecular docking and predicted pharmacokinetic parameters were done for the most active compounds. A new LC-MS/MS method was developed and validated for the quantification of 4h in rat plasma. Results: Compounds 4h, 6d, 6f, 6j and 7m revealed % edema inhibition up to 100.00%; also, 4l and 7j showed 100.00% writhing protection. Compound 4h showed dual inhibitory activity with IC50 = 0.0533 and 0.4195 μM for COX-2 and 5-LOX, respectively. Molecular docking rationalized the obtained biological activity. The pharmacokinetic parameters of 4h from rat plasma were obtained.

Identification of Major Bioactive Anti-inflammatory Compounds of Derris scandens Stem Using RAW 264.7 Cells and HPLC-UV Analysis

Derris scandens (DS) is widely recognized for its therapeutic properties, specifically its analgesic effects, which significantly alleviate muscle pain. The chemical constituents of DS stem include various isoflavone derivatives. However, there is currently a lack of specified anti-inflammatory chemical markers and analytical methods for quality control. The present study aimed to evaluate the anti-inflammatory activity of DS and its constituents using the RAW 264.7 cell model. The expression of inflammatory genes such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and 5-lipoxygenase (5-LOX) was examined using quantitative RT-PCR. An high-performance liquid chromatography with a UV detection method was developed to quantitatively analyze genistein-7-O-[α-rhamnopyranosyl-(1 → 6)]-β-glucopyranoside, genistein, derrisisoflavone A, lupalbigenin, and 6,8-diprenylgenistein in DS stem. The developed HPLC-UV method demonstrated high sensitivity with limits of detection and quantification ranging from 0.01 to 0.06 µg/mL and 0.03 to 0.18 µg/mL, respectively. The accuracy of the method ranged from 93.3 to 109.6%. Furthermore, the repeatability and reproducibility of the method were suitable, as indicated by the relative standard deviations of ≤ 3.02% and ≤ 6.22%, respectively. The DS extract notably inhibited NO production, exhibiting effects comparable to those of 500 µM diclofenac, and substantially suppressed the expression of iNOS, COX-2, IL-6, and 5-LOX of lipopolysaccharide (LPS)-induced genes. As to the pure isoflavone derivatives, the order of NO production inhibition was found to be genistein > lupalbigenin > derrisisoflavone A > 6,8-diprenylgenistein > genistein-7-O-[α-rhamnopyranosyl-(1 → 6)]-β-glucopyranoside. Genistein, derrisisoflavone A, and 6,8-diprenylgenistein significantly suppressed the upregulation of all LPS-induced genes. Consequently, these compounds are recommended as anti-inflammatory markers for the quantitative chemical analysis of DS.

Dual-target inhibitors based on COX-2: a review from medicinal chemistry perspectives

Inhibitors of COX-2 constitute a class of anti-inflammatory analgesics, showing potential against certain types of cancer. However, such inhibitors are associated with cardiovascular toxicity. Moreover, although single-target molecules possess specificity for particular targets, they often lead to poor safety, low efficacy and drug resistance due to compensatory mechanisms. A new generation of dual-target drugs that simultaneously inhibit COX-2 and another target is showing strong potential to treat cancer or reduce adverse cardiac effects. The present perspective focuses on the structure and functions of COX-2, and its role as a therapeutic target. It also explores the current state and future possibilities for dual-target strategies from a medicinal chemistry perspective.

Investigation of the Vibrational Characteristics of 6-Isocyano-1-Methyl-1H-Indole: Utilizing the Isonitrile Group as an Infrared Probe

Indole derivatives have garnered considerable attention in the realm of biochemistry due to their multifaceted properties. In this study, we undertake a systematic investigation of the vibrational characteristics of a model indole derivative, 6-isocyano-1-methyl-1H-indole (6ICMI), by employing a combination of FTIR, IR pump-probe spectroscopy, and theoretical calculations. Our findings demonstrate a strong dependence of the isonitrile stretching frequency of 6ICMI on the polarizability of protic solvents and the density of hydrogen-bond donor groups in the solvent when the isonitrile group is bonded to aromatic groups. Both experimental and theoretical analyses unveil a significant correlation between the isonitrile stretch vibration of 6ICMI and the solvent acceptor number of alcohols. Furthermore, the polarization-controlled infrared pump-probe conducted on 6ICMI in dimethyl sulfoxide provides additional support for the potential use of the isonitrile stretching mode of 6ICMI as an effective infrared probe for local environments.

Design and Development of COX-II Inhibitors: Current Scenario and Future Perspective

Innate inflammation beyond a threshold is a significant problem involved in cardiovascular diseases, cancer, and many other chronic conditions. Cyclooxygenase (COX) enzymes are key inflammatory markers as they catalyze prostaglandins production and are crucial for inflammation processes. While COX-I is constitutively expressed and is generally involved in "housekeeping" roles, the expression of the COX-II isoform is induced by the stimulation of different inflammatory cytokines and also promotes the further generation of pro-inflammatory cytokines and chemokines, which affect the prognosis of various diseases. Hence, COX-II is considered an important therapeutic target for drug development against inflammation-related illnesses. Several selective COX-II inhibitors with safe gastric safety profiles features that do not cause gastrointestinal complications associated with classic anti-inflammatory drugs have been developed. Nevertheless, there is mounting evidence of cardiovascular side effects from COX-II inhibitors that resulted in the withdrawal of market-approved anti-COX-II drugs. This necessitates the development of COX-II inhibitors that not only exhibit inhibit potency but also are free of side effects. Probing the scaffold diversity of known inhibitors is vital to achieving this goal. A systematic review and discussion on the scaffold diversity of COX inhibitors are still limited. To address this gap, herein we present an overview of chemical structures and inhibitory activity of different scaffolds of known COX-II inhibitors. The insights from this article could be helpful in seeding the development of next-generation COX-II inhibitors.

Computational Design, Synthesis, and Pharmacological Evaluation of Naproxen-Guaiacol Chimera for Gastro-Sparing Anti-Inflammatory Response by Selective COX2 Inhibition

The 4-allyl guaiacol is a natural phenolic molecule that has been widely studied for its antioxidant capacity against reactive-oxygen-species-mediated cellular damage. Therefore, we hypothesized that concomitant use of an antioxidant and NSAID may decrease the risk of gastrointestinal toxicity and make the therapy safer. To address the gastrointestinal toxicity of conventional NSAIDs, a new S-naproxen-4-allyl guaiacol chimera (MAS-1696) was computationally developed, chemically synthesized, and tested for anti-inflammatory effectiveness and gastrointestinal safety. The inhibitory potency of MAS-1696 tested against cyclooxygenase-2 (COX2), 15-lipoxygenase-2 (15-LOX2), and lipoxygenase-5 (5-LOX) in vitro revealed a stronger inhibition of COX2. Furthermore, the MAS-1696 chimera increased the COX selectivity index by 23% as compared to the parent compound naproxen, implying higher efficacy and gastric safety. In vivo data showed that MAS-1696 was less likely to cause gastrointestinal harm than naproxen while also exerting anti-inflammatory and analgesic effects equivalent to or superior to naproxen. In conclusion, MAS-1696 is orally active, bio-labile, and crystalline, making it a medication that may be administered orally.

Synthesis and Biological Evaluation of 5-Fluoro-2-Oxindole Derivatives as Potential α-Glucosidase Inhibitors

α-Glucosidase inhibitors are known to prevent the digestion of carbohydrates and reduce the impact of carbohydrates on blood glucose. To develop novel α-glucosidase inhibitors, a series of 5-fluoro-2-oxindole derivatives (3a ∼ 3v) were synthesized, and their α-glucosidase inhibitory activities were investigated. Biological assessment results showed that most synthesized compounds presented potential inhibition on α-glucosidase. Among them, compounds 3d, 3f, and 3i exhibited much better inhibitory activity with IC50 values of 49.89 ± 1.16 μM, 35.83 ± 0.98 μM, and 56.87 ± 0.42 μM, respectively, which were about 10 ∼ 15 folds higher than acarbose (IC50 = 569.43 ± 43.72 μM). A kinetic mechanism study revealed that compounds 3d, 3f, and 3i inhibited the α-glucosidase in a reversible and mixed manner. Molecular docking was carried out to simulate the affinity between the compound and α-glucosidase.

Design of Dual COX-2 and 5-LOX Inhibitors with Iron-Chelating Properties Using Structure-Based and Ligand-Based Methods

Background:

Inflammation is a critical component of many disease progressions, such as malignancy, cardiovascular and rheumatic diseases. The inhibition of inflammatory mediators synthesis by modulation of cyclooxygenase (COX) and lipoxygenase (LOX) pathways provides challenging strategy for development of more effective drugs.

Objective:

The aim of this study was to design dual COX-2 and 5-LOX inhibitors with iron-chelating properties using a combination of ligand-based (three-dimensional quantitative structure-activity relationship (3D-QSAR)) and structure-based (molecular docking) methods.

Methods:

The 3D-QSAR analysis was applied on a literature dataset consisting of 28 dual COX-2 and 5- LOX inhibitors in Pentacle software. The quality of developed COX-2 and 5-LOX 3D-QSAR models were evaluated by internal and external validation methods. The molecular docking analysis was performed in GOLD software, while selected ADMET properties were predicted in ADMET predictor software.

Results:

According to the molecular docking studies, the class of sulfohydroxamic acid analogues, previously designed by 3D-QSAR, were clustered as potential dual COX-2 and 5-LOX inhibitors with ironchelating properties. Based on the 3D-QSAR and molecular docking, 1j, 1g and 1l were selected as the most promising dual COX-2 and 5-LOX inhibitors. According to the in silico ADMET predictions, all compounds had ADMET_Risk score less than 7 and CYP_Risk score lower than 2.5. Designed compounds were not estimated as hERG inhibitors and 1j had improved intrinsic solubility (8.704) in comparison to the dataset compounds (0.411-7.946).

Conclusion:

By combining 3D-QSAR and molecular docking, three compounds (1j, 1g and 1l) were selected as the most promising designed dual COX-2 and 5-LOX inhibitors, for which good activity, as well as favourable ADMET properties and toxicity, are expected.

The indole nucleus as a selective COX-2 inhibitor and anti-inflammatory agent (2011–2022)

Anti-inflammatory bioactivity of diversely substituted indole derivatives, mainly N-1 and C-3 substituted indoles.

Synthetically-tailored and nature-derived dual COX-2/5-LOX inhibitors: Structural aspects and SAR

Inflammation is a most complex pathological process that gives birth to different diseases. Different inflammatory mediators are released during an inflammation responsible for acute pain and chronic inflammatory diseases like cancer, asthma, rheumatoid arthritis, osteoarthritis, neurodegenerative diseases, metabolic and cardiovascular disorders. The arachidonic acid pathway, which results in the production of inflammatory mediators, provides several targets for anti-inflammatory intervention. The most popularly used medications for inflammation are non-steroidal anti-inflammatory agents (NSAIDs) but it has some limitations, in particular traditional NSAIDs which inhibit the COX pathway non-selectively, producing gastrointestinal side effects, and other adverse effects like stroke and renal failure. On the other hand, selective COX-2 inhibitors commonly known as 'coxibs' produce cardiovascular side effects. Frequent inhibition of either cyclooxygenase or lipoxygenase enzyme switches the metabolism of arachidonic acid from one to another which could lead to serious consequences. Therefore, a need to develop novel, effective and safe anti-inflammatory agents which can inhibit the release of both prostaglandins and leukotrienes from the respective cyclooxygenase and lipoxygenase pathways has emerged. This resulted in the discovery of new anti-inflammatory agents derived from natural and synthetic sources as dual COX-2/5-LOX inhibitors. To further contribute towards the discovery in this field, we have attempted to summarize structural features and pharmacological activities of heterocyclic scaffolds and natural products explored as dual COX-2/5-LOX inhibitors. We have emphasized the designing of the dual inhibitors inspired by the previously reported COX-2 and 5-LOX inhibitors. This outline could render us to identify the best pharmacophores catering to dual COX-2/5-LOX inhibitory activity while improving their efficiency as anti-inflammatory agents.

Quantum mechanical, virtual screening, molecular docking, molecular dynamics, ADME and antimicrobial activity studies of some new indole-hydrazone derivatives as potent agents against E. faecalis

In this study, a new series of indole-5-carbaldehyde hydrazone derivative compounds were designed, synthesized, and their antimicrobial activities were determined by the microdilution method, and the in vitro cytotoxic effects on Beas-2b cell lines were investigated by MTT assay. When the activity results were examined, 5i12 showed promising activity against E. faecalis with MIC: 2 µg/mL compared to ampicillin, gentamicin, and vancomycin, although the antimicrobial activities of the indole derivatives were generally weaker than those of the standard drugs. Compounds showed no cytotoxic activity on the A549, MCF-7, and Beas-2b cell lines. Molecular docking studies were performed on 15 different proteins to understand the mechanism of 5i12's good antimicrobial action against E. faecalis, and it was concluded that the compounds interacted with FabH, not enough other protein structures. Molecular dynamics simulations were performed to investigate the protein-ligand stability of the most active compound against E. faecalis. The RMSD value of 5i12 varied between 0.02 and 0.16 nm during the MD simulation. The apoprotein peaked at 0.55 nm at the beginning of the simulation and stabilized below 0.5 nm. The theoretical ADME profiles of all compounds were calculated and found to comply with Lipinski and other limiting rules. In addition, some theoretical quantum parameters (HOMO-LUMO) of compounds, and both MEP analysis and geometric optimization analysis for 5i12 were calculated using the 6-311 G (d,p) base set and DFT/B3LYP theory, and the results were visualized. Communicated by Ramaswamy H. Sarma.

Active Substances from Callicarpa nudiflora Exert Anti-Cervicitis Effects and Regulate NLRP3-Associated Inflammation

Luohuazizhu suppository is a Traditional Chinese Medicine used in clinic to treat cervicitis, which is prepared from Callicarpa nudiflora Hook. et Arn (C. nudiflora), an herbal Chinese medicine named Luohuazizhu. This study aimed to figure out the active constituents of C. nudiflora and the potential mechanism for its anti-cervicitis effect. The ethanol extract in C. nudiflora (CNE) and the different fractions of CNE extracted by petroleum ether (CNE-p), dichloromethane (CNE-d), and n-butanol (CNE-b) were tested in vivo for their anti-cervicitis effects. Then the isolated compounds from the CNE-p were tested in vitro for their anti-inflammatory activities. The results displayed that CNE-p, CNE-d, and CNE-b exhibited adequate anti-cervicitis effects, with CNE-p showing the highest efficacy. Further experiment demonstrated that CNE-p could significantly inhibit the expression of NLRP3 in vitro. Six diterpenoids obtained from the CNE-p showed the ability to regulate inflammatory factor levels in vitro. Among these compounds, compounds 1 (callicarpic acid A) and 2 (syn-3,4-seco-12S-hydroxy-15,16-epoxy-4(18),8(17),3(16),14(15)-labdatetraen-3-oic acid) were the most effective agents, and they also inhibited the expression level of NLRP3 in vitro. The results confirmed that C. nudiflora has significant anti-cervicitis effects and the diterpenoids were most likely to be its active components. These data provide scientific support for the clinic usage of Luohuazizhu suppository and the development of new agents in treating cervicitis.

Design and synthesis of novel quinazolinones conjugated ibuprofen, indole acetamide, or thioacetohydrazide as selective COX-2 inhibitors: anti-inflammatory, analgesic and anticancer activities

Novel quinazolinones conjugated with indole acetamide (4a–c), ibuprofen (7a–e), or thioacetohydrazide (13a,b, and 14a-d) were designed to increase COX-2 selectivity. The three synthesised series exhibited superior COX-2 selectivity compared with the previously reported quinazolinones and their NSAID analogue and had equipotent COX-2 selectivity as celecoxib. Compared with celecoxib, 4 b, 7c, and 13 b showed similar anti-inflammatory activity in vivo, while 13 b and 14a showed superior inhibition of the inflammatory mediator nitric oxide, and 7 showed greater antioxidant potential in macrophages cells. Moreover, all selected compounds showed improved analgesic activity and 13 b completely abolished the pain response. Additionally, compound 4a showed anticancer activity in tested cell lines HCT116, HT29, and HCA7. Docking results were consistent with COX-1/2 enzyme assay results. In silico studies suggest their high oral bioavailability. The overall findings for compounds (4a,b, 7c, 13 b, and 14c) support their potential role as anti-inflammatory agents.

The Role of Organic Small Molecules in Pain Management

In this review, a timeline starting at the willow bark and ending in the latest discoveries of analgesic and anti-inflammatory drugs will be discussed. Furthermore, the chemical features of the different small organic molecules that have been used in pain management will be studied. Then, the mechanism of different types of pain will be assessed, including neuropathic pain, inflammatory pain, and the relationship found between oxidative stress and pain. This will include obtaining insights into the cyclooxygenase action mechanism of nonsteroidal anti-inflammatory drugs (NSAID) such as ibuprofen and etoricoxib and the structural difference between the two cyclooxygenase isoforms leading to a selective inhibition, the action mechanism of pregabalin and its use in chronic neuropathic pain, new theories and studies on the analgesic action mechanism of paracetamol and how changes in its structure can lead to better characteristics of this drug, and cannabinoid action mechanism in managing pain through a cannabinoid receptor mechanism. Finally, an overview of the different approaches science is taking to develop more efficient molecules for pain treatment will be presented.

Contemporary advances of cyclic molecules proposed for inflammation

This review stretches insight about the advancement (2011-2021) of synthesized non-heterocyclic, heterocyclic and natural occurring cyclic molecules for inflammation. While inflammation is very significant in the abolition of pathogens and other causes of soreness, a protracted inflammatory procedure takes to outcomes in chronic disease that might finally affect in organ failure or damage. Thus, restraining the provocative process by the use of anti-inflammatory agents is chief in controlling this damage. It also reveals other pursuit along with their anti-inflammatory activity. Molecular docking studies represent most suitable PDB (Protein Data Bank) ID for the synthesized heterocyclic molecules with their selective inhibitor. It discusses the findings presented in recent research papers and provides understanding to researchers intended for the growth of newer combinations/molecules having littler side things.

Anti-inflammatory activity of novel thiosemicarbazone compounds indole-based as COX inhibitors

BACKGROUND

In this article, a series of 20 new thiosemicarbazone derivatives containing indole were synthesized and evaluated for their anti-inflammatory potential.

METHODS

The compounds were obtained through a synthetic route of only two steps, with yields that varied between 33.6 and 90.4%, and characterized by spectroscopic and spectrometric techniques.

RESULTS

An initial screening through the lymphoproliferation assay revealed that compounds LT76, LT81, and LT87 were able to inhibit lymphocyte proliferation, with CC₅₀ of 0.56 ± 0.036, 0.9 ± 0.01 and 0.5 ± 0.07 µM, respectively, better results than indomethacin (CC₅₀ > 12 µM). In addition, these compounds were able to suppress the in-vitro production of TNF-α and NO, in addition to stimulating the production of IL-4. Reinforcing in-vitro assays, the compounds were able to inhibit COX-2 similar to Celecoxib showing greater selectivity for this isoform (LT81 SI: 23.06 versus Celecoxib SI: 11.88). Animal studies showed that compounds LT76 (64.8% inhibition after 6 h), LT81 (89% inhibition after 6 h) and LT87 (100% inhibition after 4 h) were able to suppress edema in mice after inoculation carrageenan with greater potency than indomethacin, and immunohistochemistry revealed that the groups treated with LT76, LT81 and LT87 reduced the expression of COX-2, similar or better results when compared to indomethacin. Complementarily, in-silico studies have shown that these compounds have a good pharmacokinetic profile, for respecting the parameters of Lipinski and Veber, showing their good bioavailability.

CONCLUSIONS

These results demonstrate the potency of thiosemicarbazone derivatives containing indole and confirm their importance as scaffolds of molecules with notorious anti-inflammatory activity.

Enantioselective synthesis of indole derivatives by Rh/Pd relay catalysis and their anti-inflammatory evaluation

An efficient Rh/Pd relay catalyzed intermolecular and cascade intramolecular hydroamination for the synthesis of exclusive trans 1-indolyl dihydronaphthalenols (up to 88% yield, 99% ee) is described under mild conditions. Moreover, the in silico and in vitro screening showed that the novel 1-indolyl dihydronaphthalenol products are potent lead compounds for treating inflammation disease.

Recent investigations into synthesis and pharmacological activities of phenoxy acetamide and its derivatives (chalcone, indole and quinoline) as possible therapeutic candidates

Medicinal chemistry can rightfully be regarded as a cornerstone in the public health of our modern society that combines chemistry and pharmacology with the aim of designing and developing new pharmaceutical compounds. For this purpose, many chemical techniques as well as new computational chemistry applications are used to study the utilization of drugs and their biological effects. In the biological interface, medicinal chemistry constitutes a group of interdisciplinary sciences, as well as controlling its organic, physical and computational pillars. Therefore, medicinal chemists working to design an integrated and developing system that portends an era of novel and safe tailored drugs either by synthesizing new pharmaceuticals or to improving the processes by which existing pharmaceuticals are made. It includes researching the effects of synthetic, semi-synthetic and natural biologically active substances based on molecular interactions in terms of molecular structure with triggered functional groups or the specific physicochemical properties. The present work focuses on the literature survey of chemical diversity of phenoxy acetamide and its derivatives (Chalcone, Indole and Quinoline) in the molecular framework in order to get complete information regarding pharmacologically interesting compounds of widely different composition. From a biological and industrial point of view, this literature review may provide an opportunity for the chemists to design new derivatives of phenoxy acetamide and its derivatives that proved to be the successful agent in view of safety and efficacy to enhance life quality.

Synthesis of indole-tethered [1,3,4]thiadiazolo and [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids as anti-pancreatic cancer agents

New indole-tethered [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one (8a-j) and [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids (9a-e) were synthesized using [4+2] cycloaddition reactions of functionalized 1,3-diazabuta-1,3-dienes with indole-ketenes. All molecular hybrids were structurally characterized by spectroscopic techniques (IR, NMR, and HRMS) and screened for their anti-pancreatic cancer activity in vitro. The [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids (9a-e) showed stronger anti-pancreatic cancer activity than the [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one hybrids (8a-j) against the PANC-1 cell line. Compound 9d bearing an ortho-chlorophenyl moiety emerged as the most potent anti-pancreatic cancer agent with an IC50 value of 7.7 ± 0.4 µM, much superior to the standard drug Gemcitabine (IC50 > 500 µM). The discovery of these [1,3,4]thiadiazolo and [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids elicits their potentials as pursuable candidates for pancreatic cancer chemotherapy.

Dual COX and 5-LOX inhibition by clerodane diterpenes from seeds of Polyalthia longifolia (Sonn.) Thwaites

Natural metabolites with their specific bioactivities are being considered as a potential source of materials for pharmacological studies. In this study, we successfully isolated and identified five known clerodane diterpenes, namely 16-oxo-cleroda-3,13(14)E-dien-15-oic acid (1), 16-hydroxy-cleroda-3,13-dien-15-oic acid (2), 16-hydroxy-cleroda-4(18),13-dien-16,15-olide (3), 3α,16α-dihydroxy-cleroda-4(18),13(14)Z-dien-15,16-olide (4), and 16α-hydroxy-cleroda-3,13(14)Z-dien-15,16-olide (5) from the methanolic extract of seeds of Polyalthia longifolia. Initially, all the isolated metabolites were investigated for COX-1, COX-2, and 5-LOX inhibitory activities using the standard inhibitory kits. Of which, compounds 3, 4, and 5 exhibited to be potent COX-1, COX-2, and 5-LOX inhibitors with the IC₅₀ values similar or lower to those of the reference drugs. To understand the underlying mechanism, these compounds were subjected to molecular docking on COX-1, COX-2, and 5-LOX proteins. Interestingly, the in silico study results were in high accordance with in vitro studies where compounds 3, 4, and 5 hits assumed interactions and binding pattern comparable to that of reference drugs (indomethacin and diclofenac), as a co-crystallized ligand explaining their remarkable dual (COX/LOX) inhibitor actions. Taken together, our findings demonstrated that compounds 3, 4, and 5 functioned as dual inhibitors of COX/5-LOX and can contribute to the development of novel, more effective anti-inflammatory drugs with minimal side-effects.

Novel tetrazole-based selective COX-2 inhibitors: Design, synthesis, anti-inflammatory activity, evaluation of PGE2, TNF-α, IL-6 and histopathological study

To search for effective and selective COX-2 inhibitors, four novel series of tetrazole derivatives were designed based on bioisosteric replacement of SO₂NH₂ in celecoxib with tetrazole ring incorporating different central moieties as chalcone (2a-f), isoxazole (3a-c) or pyrazole (4a-c & 5a-c). Target tetrazoles were synthesized and their structures were confirmed by spectroscopic techniques and elemental analyses. All target compounds were more selective for COX-2 isozyme than COX-1 when compared to standard drugs indomethacin and celecoxib. Compounds 3b, 3c, 4b, 4c, 5b and 5c exhibited potent in vitro COX-2 inhibitory activity (IC₅₀ = 0.039-0.065 μM). Trimethoxy derivatives 3c, 4c and 5c acquired superior COX-2 selectivity index values (SI = 297.67-317.95) and were 1.1 fold higher than celecoxib (SI = 282.22). The most active six compounds were evaluated for their in vivo anti-inflammatory activity and serum levels of PGE₂, TNF-α and IL-6 in addition to their ulcerogenic liability and histopathological profile. At a dose of 50 mg/Kg, compounds 3c and 5c showed better anti-inflammatory activity (% edema inhibition = 29.209-42.643) than celecoxib (% edema inhibition = 28.694-40.114) at different time intervals and were less ulcerogenic (UI = 0.123 and 0.11 in sequent) than celecoxib (UI = 0.167). Also, they displayed potent inhibitory effect on the production of PGE₂ (% inhibition = 81.042 and 82.724 in sequent) greater than celecoxib (% inhibition = 79.666). Compound 5c decreased rat serum concentrations of both TNF-α (% inhibition = 55.349) and IL-6 (% inhibition = 61.561) in a comparable or better activity to celecoxib as reference drug. Finally, docking poses of the most active compounds showed strong binding interactions and effective overall docking energy scores explaining their remarkable COX-2 inhibitory activity.

Quinones as preventive agents in Alzheimer's diseases: focus on NLRP3 inflammasomes

OBJECTIVES

Alzheimer's disease (AD) is a hidden neurological degenerative disease, which main clinical manifestations are cognitive dysfunction, memory impairment and mental disorders. Neuroinflammation is considered as a basic response of the central nervous system. NLRP3 (Nucleotide-binding domain leucine-rich repeat (NLR) and pyrin domain containing receptor 3) inflammasome is closely related to the occurrence of neuroinflammation. Activation of the NLRP3 inflammasome results in the release of cytokines, pore formation and ultimately pyroptosis, which has demonstrated one of the critical roles in AD pathogenesis. Inhibition of the activity of NLRP3 is one of the focuses of the research. Therefore, NLRP3 represents an attractive pharmacological target, and discovery compounds with good NLRP3 inhibitory activity are particularly important.

KEY FINDINGS

Quinones have good neuroprotective effects and prevent AD, which may be related to their regulation of inflammatory response. The molecular docking was used to explore 12 quinones with AD prevention and treatment and NLRP3. Docking results showed that the combination of anthraquinones and NLRP3 were the best, and the top two chemical compounds were Purpurin and Rhein, which are the most promising NLRP3 inhibitors.

SUMMARY

These quinones may provide the theoretical basis for finding lead compounds for novel neuroprotective agents.

Current scenario of indole derivatives with potential anti-drug-resistant cancer activity

Cancer chemotherapy is frequently hampered by drug resistance, so the resistance to anticancer agents represents one of the major obstacles for the effective cancer treatment. Indole derivatives have the potential to act on diverse targets in cancer cells and exhibit promising activity against drug-resistant cancers. Moreover, some indole-containing compounds such as Semaxanib, Sunitinib, Vinorelbine, and Vinblastine have already been applied in clinics for various kinds of cancer even drug-resistant cancer therapy. Thus, indole derivatives are one of significant resources for the development of novel anti-drug-resistant cancer agents. This review focuses on the recent development of indole derivatives with potential therapeutic application for drug-resistant cancers, and the mechanisms of action, the critical aspects of design as well as structure-activity relationships, covering articles published from 2010 to 2020.

Identification and development of thiazole leads as COX-2/5-LOX inhibitors through in-vitro and in-vivo biological evaluation for anti-inflammatory activity

Treatment of inflammation using NSAIDs is coupled with a risk of severe gastric adverse events. Development of dual COX-2/5-LOX inhibitors turns out to be an imperative area devoted to safer NSAIDs. A series of thiourea, thiazole, and thiazolidene derivatives were synthesized by green synthetic approach and COX-1, COX-2 and 5-LOX inhibition screening resulted in the identification of a potent compound 6l with IC₅₀ of 5.55 µM, 0.09 µM, and 0.38 µM respectively. Compound 6l made significant decrease (60.82%) in the carrageenan-induced edema in male Wistar rats. qRT-PCR analysis and determination of PGE₂ and LTB₄ in the rat paw tissues indicated that this thiazole based dual inhibitor significantly reduced the expression of COX-2 and 5-LOX genes besides the marked reduction in both PGE₂ and LTB₄ levels. The gastric safety profiling revealed an enhanced gastrointestinal safety of the compound 6l on histopathological examination. Molecular docking studies at COX-2 and 5-LOX active sites were consistent with biological studies by significant protein-ligand interaction. Besides, results of in-vitro PGE₂ and LTB₄ studies on RAW 264.7 cells as well as antioxidant studies were parallel to the dual inhibitory activity. The present investigations identify a promising lead having anti-inflammatory potential with an improved gastric safety profile.

Design, Synthesis and Investigation of the Potential Anti-Inflammatory Activity of 7-O-Amide Hesperetin Derivatives

To develop new anti-inflammatory agents, a series of 7-O-amide hesperetin derivatives was designed, synthesized and evaluated for anti-inflammatory activity using RAW264.7 cells. All compounds showed inhibitory effect on LPS-induced NO production. Among them, 7-O-(2-(Propylamino)-2-oxoethyl)hesperetin (4d) and 7-O-(2-(Cyclopentylamino)-2-oxoethyl)hesperetin (4k) with hydrophobic side chains exhibited the most potent NO inhibitory activity (IC₅₀ = 19.32 and 16.63 μM, respectively), showing stronger inhibitory effect on the production of pro- inflammatory cytokines tumor necrosis factor (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) than indomethacin and celecoxib at 10 μM. The structure-activity relationships (SARs) suggested that the 7-O-amide unit was buried in a medium-sized hydrophobic cavity of the bound receptor. Furthermore, compound 4d could also significantly suppress the expression of inducible nitric oxide synthase enzymes (iNOS) and cyclooxygenase-2 (COX-2), through the nuclear factor-kappa B (NF-κB) signaling pathway.