2-Substituted Benzoxazoles as Potent Anti-Inflammatory Agents: Synthesis, Molecular Docking and In Vivo Anti-Ulcerogenic Studies

2021 ◽  
Vol 18 ◽  
Author(s):  
Iqra Hamid ◽  
Humaira Nadeem ◽  
Sameen Fatima Ansari ◽  
Sonia Khiljee ◽  
Inzamam Abbasi ◽  
...  

Background: Non-steroidal anti-inflammatory drugs (NSAIDs) are the commonly used therapeutic interventions of inflammation and pain that competitively inhibit the cyclooxygenase (COX) enzymes. Several side effects like gastrointestinal and renal toxicities are associated with the use of these drugs. The therapeutic anti-inflammatory benefits of NSAIDs are produced by the inhibition of COX-2 enzymes, while undesirable side effects arise from the inhibition of COX-1 enzymes. Objectives: In the present study, a new series of 2-substituted benzoxazole derivatives 2(a-f) and 3(a-e) were synthesized in our lab as potent anti-inflammatory agents with outstanding gastro-protective potential. The new analogs 2(a-f) and 3(a-e) were designed depending upon the literature review to serve as ligands for the development of selective COX-2 inhibitors. Methods: The synthesized analogs were characterized using different spectroscopic techniques (FTIR, 1HNMR, 13CNMR) and elemental analysis. All synthesized compounds were screened for their binding potential in the protein pocket of COX-2 and evaluated for their anti-inflammatory potential in animals using the carrageenan-induced paw edema method. Further 5 compounds were selected to assess the in vivo anti-ulcerogenic activity in an ethanol-induced anti-ulcer rat model. Results: Five compounds (2a, 2b, 3a, 3b and 3c) exhibited potent anti-inflammatory activity and significant binding potential in the COX-2 protein pocket. Similarly, these five compounds demonstrated a significant gastro-protective effect (p<0.01) in comparison to the standard drug, Omeprazole. Conclusion: Depending upon our results, we hypothesize that 2-substituted benzoxazole derivatives have excellent potential to serve as candidates for the development of selective anti-inflammatory agents (COX-2 inhibitors). However, further assessments are required to delineate their underlying mechanisms.

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2425 ◽  
Author(s):  
Anamaria Cristina ◽  
Denisa Leonte ◽  
Laurian Vlase ◽  
László Bencze ◽  
Silvia Imre ◽  
...  

Non-steroidal anti-inflammatory drugs (NSAIDs) are an important pharmacological class of drugs used for the treatment of inflammatory diseases. They are also characterized by severe side effects, such as gastrointestinal damage, increased cardiovascular risk and renal function abnormalities. In order to synthesize new anti-inflammatory and analgesic compounds with a safer profile of side effects, a series of 2,6-diaryl-imidazo[2,1-b][1,3,4]thiadiazole derivatives 5a–l were synthesized and evaluated in vivo for their anti-inflammatory and analgesic activities in carrageenan-induced rat paw edema. Among all compounds, 5c showed better anti-inflammatory activity compared to diclofenac, the standard drug, and compounds 5g, 5i, 5j presented a comparable antinociceptive activity to diclofenac. None of the compounds showed ulcerogenic activity. Molecular docking studies were carried out to investigate the theoretical bond interactions between the compounds and target, the cyclooxygenases (COX-1/COX-2). The compound 5c exhibited a higher inhibition of COX-2 compared to diclofenac.


2020 ◽  
Vol 17 ◽  
Author(s):  
Deepak Kumar Singh ◽  
Mayank Kulshreshtha ◽  
Yogesh Kumar ◽  
Pooja A Chawla ◽  
Akash Ved ◽  
...  

Background: The pyrazolines give the reactions of aliphatic derivatives, resembling unsaturated compounds in their behavior towards permanganate and nascent hydrogen. This nucleus has been associated with various biological activities including inflammatory. Thiazolinone is a heterocyclic compound that contains both sulfur and nitrogen atom with a carbonyl group in their structure.Thiazolinone and their derivatives have attracted continuing interest because of their various biological activities, such as anti-inflammatory, antimicrobial, anti-proliferative, antiviral, anticonvulsant etc. The aim of the research was to club pyrazoline nucleus with thiazolinone in order to have significantanti-inflammatory activity. The synthesized compounds were chemically characterized for the establishment of their chemical structures and to evaluate as anti-inflammatory agent. Method: In the present work, eight derivatives of substituted pyrazoline (PT1-PT8) were synthesized by a three step reaction.The compounds were subjected to spectral analysis by Infrared, Mass and Nuclear magnetic resonance spectroscopy and elemental analysis data. All the synthesized were evaluated for their in vivo anti-inflammatory activity. The synthesized derivatives were evaluated for their affinity towards target COX-1 and COX-2, using indomethacin as the reference compound molecular docking visualization through AutoDock Vina. Results: Compounds PT-1, PT-3, PT-4 and PT-8 exhibited significant anti-inflammatory activity at 3rd hour being 50.7%, 54.3%, 52.3% and 57% respectively closer to that of the standard drug indomethacin (61.9%).From selected anti-inflammatory targets, the synthesized derivatives exhibited better interaction with COX-1 and COX-2 receptor, where indomethacin showed docking score of -6.5 kJ/mol, compound PT-1 exhibited highest docking score of -9.1 kJ/mol for COX-1 and compound PT-8 having docking score of 9.4 kJ/mol for COX-2. Conclusion: It was concluded that synthesized derivatives have more interaction with COX-2 receptors in comparison to the COX-1 receptors because the docking score with COX-2 receptors were very good. It is concluded that the synthesized derivatives (PT-1 to PT-8) are potent COX-2 inhibitors.


2021 ◽  
Vol 28 ◽  
Author(s):  
Josiane Viana Cruz ◽  
Joaquín María Campos Rosa ◽  
Njogu Mark Kimani ◽  
Silvana Giuliatti ◽  
Cleydson Breno Rodrigues dos Santos

: This article presents a simplified view of celecoxib as a potential inhibitor in the treatment of inflammatory diseases. The enzyme cyclooxygenase (COX) has, predominantly, two isoforms called cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2). The former plays a constitutive role that is related to homeostatic effects in renal and platelets, while the latter is mainly responsible for induction of inflammatory effects. Since COX-2 plays an important role in the pathogenesis of inflammatory diseases, it has been signaled as a target for the planning of anti-inflammatory intermediates. Many inhibitors developed and planned for COX-2 inhibition have presented side effects to humans, mainly in the gastrointestinal and/or cardiovascular tract. Therefore, it is necessary to design new potential COX-2 inhibitors, which are relatively safe and without side effects. To this end, of the generation of non-steroidal anti-inflammatory drugs from “coxibs”, celecoxib is the only potent selective COX-2 inhibitor that is still commercially available. Thus, the compound celecoxib became a commercial prototype inhibitor for the development of anti-inflammatory agents for COX-2 enzyme. In this review, we provide highlights where such inhibition should provide a structural basis for the design of promising new non-steroidal anti-inflammatory drugs (NSAIDs) which act as COX-2 inhibitors with lesser side effects on the human body.


Molecules ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 220 ◽  
Author(s):  
Ameen Ali Abu-Hashem ◽  
Sami A Al-Hussain ◽  
Magdi E. A. Zaki

Novel (4-methoxy or 4,8-dimethoxy)-3-methyl-N-(6-oxo-2-thioxo-1,2,3, 6-tetrahydro- pyrimidin-4-yl) benzo [1,2-b: 5, 4-b’] difuran-2-carboxamide (5a–b) has been synthesized by the reaction of visnagenone–ethylacetate (2a) or khellinone–ethylacetate (2b) with 6-aminothiouracil in dimethylformamide or refluxing of benzofuran-oxy-N-(2-thioxopyrimidine) acetamide (4a–b) in sodium ethoxide to give the same products (5a,b) in good yields. Thus, compounds 5a–b are used as an initiative to prepare many new heterocyclic compounds such as 2-(4-(3-methylbenzodifuran- 2-carbox-amido) pyrimidine) acetic acid (6a–b), N-(thiazolo[3, 2-a]pyrimidine)-3-methylbenzo- difuran-2-carboxamide (7a–b), N-(2-thioxopyrimidine)-methylbenzodifuran-2-carbimidoylchloride (8a–b), N-(2-(methyl-thio) pyrimidine)-3-methylbenzodifuran-2-carbimidoylchloride (9a–b), N-(2, 6 -di(piperazine or morpholine)pyrimidine)-1-(3-methylbenzodifuran)-1-(piperazine or morpholine) methanimine(10a–d), 8-(methylbenzodifuran)-thiazolopyrimido[1,6-a][1,3,5]triazine-3,5-dione (11a –b), 8-(3-methyl benzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-trione (12a–b), and 2,10 -di(sub-benzylidene)-8-(3-methylbenzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-3,5,11- trione (13a–f). All new chemical structures were illustrated on the basis of elemental and spectral analysis (IR, NMR, and MS). The new compounds were screened as cyclooxygenase-1/ cyclooxygenase-2 (COX-1/COX-2) inhibitors and had analgesic and anti-inflammatory activities. The compounds 10a–d and 13a–f had the highest inhibitory activity on COX-2 selectivity, with indices of 99–90, analgesic activity of 51–42% protection, and anti-inflammatory activity of 68%–59%. The inhibition of edema for the same compounds, 10a–d and 13a–f, was compared with sodium diclofenac as a standard drug.


MedChemComm ◽  
2016 ◽  
Vol 7 (12) ◽  
pp. 2309-2327 ◽  
Author(s):  
Fatma A. Ragab ◽  
Helmi I. Heiba ◽  
Marwa G. El-Gazzar ◽  
Sahar M. Abou-Seri ◽  
Walaa A. El-Sabbagh ◽  
...  

A novel series of thiadiazole derivatives were designed and synthesized for evaluation as selective COX-2 inhibitors in vitro and were investigated in vivo as anti-inflammatory and analgesic agents against carrageenan-induced rat paw oedema model in irradiated rats.


2020 ◽  
Vol 27 ◽  
Author(s):  
Jiahua Cui ◽  
Jinping Jia

: COX-2, a key enzyme that catalyzed the rate-limiting steps in the conversion of arachidonic acid to prostaglandins, played a pivotal role in inflammatory process. Different from other family members, COX-2 was barely detectable in normal physiological conditions and highly inducible during acute inflammatory response of human bodies to injuries or infections. Therefore, the therapeutic utilization of selective COX-2 inhibitors has already been considered as an effective approach for the treatment of inflammation with diminished side effects. Currently, both traditional and newer NSAIDs are the commonly prescribed medications that treat inflammatory disease by targeting COX-2. However, due to the cardiovascular side-effects of the NSAIDs, finding reasonable alternatives for these frequently prescribed medicines are a hot spot in medicinal chemistry research. Naturally-occurring compounds have been reported to inhibit COX-2, thereby possessing beneficial effects against inflammation and certain cell injury. The review mainly concentrated on recently identified natural products and derivatives as COX-2 inhibitors, the characteristics of their structural core scaffolds, their anti-inflammatory effects, molecular mechanisms for enzymatic inhibition and related structure-activity relationships. According to the structural features, the natural COX-2 inhibitors were mainly divided into the following categories: natural phenols, flavonoids, stilbenes, terpenoids, quinones and alkaloids. Apart from the anti-inflammatory activities, a few dietary COX-2 inhibitors from nature origin also exhibited chemopreventive effects by targeting COX-2-mediated carcinogenesis. The utilization of these natural remedies in future cancer prevention was also discussed. In all, the survey on the characterized COX-2 inhibitors from natural sources paths the further development of more potent and selective COX-2 inhibitors in the future.


2007 ◽  
Vol 57 (1) ◽  
pp. 13-30 ◽  
Author(s):  
Mange Yadav ◽  
Shrikant Shirude ◽  
Devendra Puntambekar ◽  
Pinkal Patel ◽  
Hetal Prajapati ◽  
...  

Studies in 3,4-diaryl-1,2,5-oxadiazoles and theirN-oxides: Search for better COX-2 inhibitorsA series of 3,4-diaryl-1,2,5-oxadiazoles and 3,4-diaryl-1,2,5-oxadiazoleN-oxides were prepared and evaluated for COX-2 and COX-1 binding affinityin vitroand for anti-inflammatory activity by the rat paw edema method.p-Methoxy (p-OMe) substituted compounds 9, 21, 34, 41, 42 showed COX-2 enzyme inhibition higher than that showed by compounds with other substituents. 3,4-Di(4-methoxyphenyl)-1,2,5-oxadiazoleN-oxide (42) showed COX-2 enzyme inhibition of 54% at 22 μmol L-1and COX-1 enzyme inhibition of 44% at 88 μmol L-1concentrations, but showed very lowin vivoanti-inflammatory activity. Its deoxygenated derivative (21) showed lower COX-2 enzyme inhibition (26% at 22 μmol L-1) and higher COX-1 enzyme inhibition (53% at 88 μmol L-1) but, markedin vivoanti-inflammatory activity (71% at 25 mg kg-1)vs.celecoxib (48% at 12.5 mg kg-1). Molecular modeling (docking) studies showed that the methoxy group is positioned in the vicinity of COX-2 secondary pocket and it also participates in hydrogen bonding interactions in the COX-2 active site. These preliminary studies suggest thatp-methoxy (p-OMe) group in one of benzene rings may give potentially active leads in this series of oxadiazole/N-oxides.


2015 ◽  
Vol 18 (2) ◽  
pp. 90-96 ◽  
Author(s):  
Mohammad Firoz Khan ◽  
Sabreena Aleem Nabila ◽  
Ridwan Bin Rashid ◽  
Mohammad Sharifur Rahman ◽  
Abu Asad Chowdhury ◽  
...  

Cyclooxygenase-2 (COX-2) is an inducible enzyme that causes inflammation. COX-2 inhibitors are clinically effective anti-inflammatory agents with less gastrointestinal and renal toxicities. However, they lack anti-thrombotic activity and hence lead to increased incidences of adverse cardiovascular thrombotic events, including myocardial infarction. Therefore, there is still need to develop COX-2 inhibitors with better therapeutic effects and tolerability. The aim of the present study is to explore the anti-inflammatory activity of five lichen metabolites by conducting virtual screenings. In this regard, molecular docking simulations were carried out for the lichen metabolites namely atranorin, diffractic acid, lecanoric acid, salazinic acid and usnic acid with human COX-2 enzyme and the docked results were compared with the standard reference ligands (Celecoxib and Rofecoxib). Among all the docked ligands, the lecanoric acid demonstrated best binding affinity -9.83 kcal/mol followed by atranorin (-8.7 kcal/mol) and diffractic acid (-8.6 kcal/mol) which are comparable to the reference ligands celecoxib (-12.3 kcal/mol) and rofecoxib (-11.2 kcal/mol). The salazinic acid and usnic acid has shown binding affinity of -7.9 kcal/mol and -4.7 kcal/mol, respectively. Moreover, all the ligands except atranorin and diffractic acid satisfied Lipinski’s rule of 5. From the docking results it was revealed that the lichen metabolites might have inhibitory activity against COX-2 enzyme, and are expected to be useful in conducting in vivo anti-inflammatory screenings on animal model which may lead to the development of more effective and potent new chemical entities with anti-inflammatory properties.Bangladesh Pharmaceutical Journal 18(2): 90-96, 2015


New two derivatives of 2- methyl benzoimidazole were designed, synthesized and evaluated as a potential cyclooxygenase-2 [COX-2] inhibitors. The synthesized compounds have been recognized according to their spectral FT-IR, 1H-NMR data and physical pro- perties. The newly synthesized compounds were investigated in vivo for their anti-inflammatory activities using egg-white stimulated paw edema method with respect to the effect of propylene glycol 50%v/v [control group] and the ibuprofen [10mg/kg i.p.] was selected as a reference ligand. New compounds showed a significantly higher in vivo anti-inflammatory activity compared with ibuprofen as a reference drug. COX-2 selectivity evaluation through molecular docking via GOLD suite [v. 5.6.2.]. The new compounds via molecular docking showed significant higher activities when compared with ibuprofen as referenced drugs because of having hydrogen bonding interaction toward the key amino acids within COX-2 structure and all these results were compatible with the study of in vivo acute anti-inflammatory activities for tested compounds. ADME studies were performed to predict absorption, bioavailability, topological polar surface area, and drug-likeness. The results of ADME studies showed that all synthesized compounds absorbed from the gastrointestinal tract.


2020 ◽  
Vol 32 (12) ◽  
pp. 3209-3218
Author(s):  
K. Praveen Kumar ◽  
Y. Prashanthi ◽  
G. Rambabu ◽  
Md. Ataur Rahman ◽  
J.S. Yadav

In this study, we report the design, synthesis and the biological evaluation of 19 analogues of 2-mercapto benzoxazole coupled benzyl triazoles (BOTs) based on analysis of the binding site and literature of chemical space. These BOTs were evaluated both in vitro and in vivo for their anti-inflammatory activity. Eleven compounds showed less than 10 μM in vitro COX-2 enzyme activities. The most potent analogue among the BOT analogues were BOT15, BOT3 and BOT19 with IC50 3.40 μM, 4.50 μM and 4.57 μM respectively against COX-2. The in vivo anti-inflammatory activity of two BOTs has significantly higher than that of standard drug, ibuprofen. 2-Mercapto benzoxazole coupled benzyl triazoles (BOTs) were also tested for their antioxidant capacity and proved to be an as active scavenger, better than ascorbic acid.


Sign in / Sign up

Export Citation Format

Share Document