Synthesized Benzimidazole Derivatives Research Articles

Molecular Modeling, Synthesis, and Antihyperglycemic Activity of the New Benzimidazole Derivatives - Imidazoline Receptor Agonists.

The paper presents the results of a study on the first synthesized benzimidazole derivatives obtained from labile nature carboxylic acids. The synthesis conditions of these substances were studied, their structure was proved, and some components were found to have sugar-reducing activity on the model of alloxan diabetes in rats. The study used molecular modeling methods such as docking based on the evolutionary model (igemdock), RP_HPLC method to monitor the synthesis reaction, and 1H NMR and 13C NMR, and other methods of organic chemistry to confirm the structures of synthesized substances. The docking showed that the ursodeoxycholic acid benzimidazole derivatives have high tropics to all imidazoline receptor carriers (PDB ID: 2XCG, 2bk3, 3p0c, 1QH4). The ursodeoxycholic acid benzimidazole derivative and arginine and histidine benzimidazole derivatives showed the highest sugar-lowering activity in the experiment on alloxan-diabetic rats. For these derivatives, the difference in glucose levels of treated rats was significant against untreated control. Therefore, the new derivatives of benzimidazole and labile natural organic acids can be used to create new classes of imidazoline receptor inhibitors for the treatment of diabetes mellitus and hypertension.

Novel 5-fluoro-6-(4-(2-fluorophenyl)piperazin-1-yl)-2-(4-(4-methylpiperazin- 1-yl)phenyl)-1H-benzo[d]imidazole Derivatives as Promising Urease Inhibitors

Background: Highly pathogenic bacteria colonize and maintain themselves with the aid of an enzyme called urease. Consequently, inhibiting urease enzymes can be a promising method for preventing ureolytic bacterial infections. Objective: This study aimed at synthesizing and screening a novel series of benzimidazole derivatives. Methods: Nine novel benzimidazole derivatives 10α-Ɣ were synthesized and isolated. Their structures were elucidated by 1H-NMR and IR spectroscopic techniques besides HRMS. The urease inhibition activity of these compounds was evaluated using the standard urease enzyme inhibition kit. An MTT assay was performed on the NIH-3T3 cell line to investigate the cytotoxicity profile. Results: All benzimidazoles 10α-Ɣ exhibited higher urease inhibition activity (3.06–4.40 μM) than the reference standards thiourea and hydroxyurea (IC50: 22 and 100 μM, respectively). 10Ɣ-1 and 10α-1 exhibited the best activity with the IC50 values of 3.06 and 3.13 μM, respectively. Investigation of the cytotoxicity profile of the target compound showed that all 10α-Ɣ have IC50 values higher than 50 μM on the tested cell line. Conclusion: The results showed that synthesized benzimidazole derivatives could be highly effective as urease inhibitors.

The microtubule cytoskeleton: A validated target for the development of 2-Aryl-1H-benzo[d]imidazole derivatives as potential anticancer agents

In this study, a series of 2-Aryl-1H-benzo[d]imidazole derivatives were developed to target intra- and extracellular microtubule networks. Compounds O-7 and O-10 showed impressive anti-proliferative activity across various tested cell lines, demonstrating selectivity indexes of 151.7 and 61.9, respectively. O-7 achieved an IC50 value of 0.236 ± 0.096 μM, while O-10 showed an IC50 value of 0.622 ± 0.13 μM against A549 cell lines. The induction of early-stage apoptosis in a dose-dependent manner further underscored the potential of O-7 and O-10 as effective anti-proliferative agents. O-7 and O-10 exhibited substantial inhibition of wound closure, with wound closure percentages decreasing from 23% at 0 μM to 0.43% and 2.62% at 20 μM, respectively. Colony formation reduction rates were impressive, with O-7 at 74.2% and O-10 at 81.2%. These results indicate that the O-7 and O-10 can impede cancer cell migration and have a high potential to curtail colony formation. The mode of action investigations for O-7 and O-10 revealed that O-7 could inhibit in vitro tubulin polymerization and disrupt the intracellular microtubule cytoskeleton. This disruption led to cell cycle arrest in the G2/M phase, indicating that O-7 exerts its anticancer activity through microtubule destabilization. However, O-10 shows a different mode of action than O-7 and requires further investigation. Overall, our study showcases the potential of the synthesized benzimidazole derivatives as novel and selective anticancer agents, motivating further exploration of their pharmacological properties and therapeutic applications.

Synthesis, characterization, and biological investigations of potentially bioactive heterocyclic compounds containing benzimidazole nucleus

Six benzimidazole derivatives have been synthesized and characterized using spectroscopic techniques such as IR, 1H NMR, 13C NMR, and mass spectrometry. The computational calculations and geometrical optimization of newly synthesized benzimidazole derivatives were investigated using Gaussian software in conjunction with the Density functional theory (DFT)/B3LYP method with a 6–311++G(d,p) basis set at gaseous phase. In addition, the quantum chemical parameters of the compounds were evaluated to comprehend the structural activity concept. The synthesized compounds were tested for cytotoxicity using the MTT assay and antioxidant activity using the DPPH scavenging activity and the Ferrous-Ion Chelating Assay. All the compounds tested showed antioxidant, antidibetic, cytotoxic potential, with compounds 4c and 4f being the best of all derivatives. The agar diffusion method was used to conduct antimicrobial assays for bacteria and fungi. Even though none of the compounds were found to be effective against fungi isolates and some had a poor anti-bacterial effect, compound 4f had a significantly higher antibacterial effect against all bacteria strains (S. aureus, Bacillus cereus, E. coli, and Acetobacter sp.). Furthermore, in vitro anticancer properties of synthesized compounds were validated using in silico molecular docking simulation studies. Compound 4c had the highest binding affinity of all the ligands, with a binding energy of −5.9 Kcal/mol and three hydrogen bonds.

Design, synthesis and antimicrobial evaluation of benzimidazole containing 4-thiazolidinone based 5-arylidene derivatives

In an attempt to design a potent class of antimicrobials, we have synthesized benzimidazole derivatives based on 4-thiazolidinone which possessed 5-arylidenes 5a-o by using different catalysts under multistep conventional synthesis. Structures of the synthesized compounds have been established based on spectral data and compounds have been screened for their antimicrobial activity. Compound 5j shows maximum potency against all Gram-positive bacteria with a minimum inhibitory concentration (MIC) in the range of 25-50 μg/mL while moderate activity against Gram-negative bacterial strains is observed with a MIC value of 62.50 μg/mL. Compound 5n is found to be the most active against fungal strains with a MIC value of 250 μg/mL.

Pyridyl Methylsulfinyl Benzimidazole Derivatives as Promising Agents against Giardia lamblia and Trichomonas vaginalis.

Protozoan parasites, such as Giardia lamblia and Trichomonas vaginalis, cause the most prevalent infections in humans in developing countries and provoke significant morbidity and mortality in endemic countries. Despite its side-effects, metronidazole is still the drug of choice as a giardiacidal and trichomonacidal tissue-active agent. However, the emergence of metronidazole resistance and its evolved strategies of parasites to evade innate host defenses have hindered the identification and development of new therapeutic strategies against these parasites. Here, we tested five synthesized benzimidazole derivatives as possible drugs for treating giardiasis and trichomoniasis, probing the bifunctional enzyme glucose 6-phosphate dehydrogenase::6-phosphogluconolactone from G. lamblia (GlG6PD::6PGL) and T. vaginalis (TvG6PD::6PGL) as a drug target. The investigated benzimidazole derivatives were H-B2M1, H-B2M2, H2N-BZM6, O2N-BZM7, and O2N-BZM9. The recombinant enzymes were used in inhibition assays, and in silico computational predictions and spectroscopic studies were applied to follow the structural alteration of the enzymes and identify the possible mechanism of inhibition. We identified two potent benzimidazole compounds (O2N-BZM7 and O2N-BZM9), which are capable of inhibiting both protozoan G6PD::6PGL enzymes and in vitro assays with these parasites, showing that these compounds also affect their viability. These results demonstrate that other therapeutic targets of the compounds are the enzymes GlG6PD::6PGL and TvG6PD::6PGL, which contribute to their antiparasitic effect and their possible use in antigiardial and trichomonacidal therapies.

Preferential Synthesis and Pharmacological Evaluation of Mono‐ and Di‐substituted Benzimidazole Derivatives

AbstractA series of substituted benzimidazoles were synthesized by condensing o‐phenylenediamine with aromatic aldehydes in water using surfactants as catalyst. Mono and disubstituted benzimidazoles were formed preferentially with benzalkonium chloride and sodium dodecyl sulfate respectively. In silico molecular docking study revealed that 1‐(4‐chlorobenzyl)‐2‐(4‐chlorophenyl)‐1H‐benzo[d]imidazole bound strongly with delta, mu and kappa opioid receptors with binding scores of −9.4, −8.7 and −9.9 Kcal/mol respectively. This derivative also possessed highest binding (−9.0 Kcal/mol) against tubulin (binding score of albendazole was −6.4 Kcal/mol). The molecule also showed potential antibacterial activity with MIC50ranging 16–128 μg/ml inin vitroantibacterial assay. Two benzimidazole derivatives showed powerful interaction with cyclooxygenase‐1 and cyclooxygenase‐2 (−8.1 and −8.9 Kcal/mol respectively) indicating their high analgesic and anti‐inflammatory potentials. All the compounds produced significant binding (−5.2 to −8.2 Kcal/mol) towards urate oxidase, glutathione reductase and peroxiredoxin. Monosubstituted derivative 4‐(1H‐benzo[d]imidazol‐2‐yl)phenol displayed superior binding (−6.5 Kcal/mol) with glucosamine 6‐phosphate synthase compared to ciprofloxacin (−6.3 Kcal/mol). In PASS analysis, monosubstituted derivatives demonstrated significant drug‐like potential (Pa>0.7). Hence, the synthesized benzimidazole derivatives can be used as potential leads for developing new drugs.

Design and synthesis of benzimidazole derivatives as apoptosis-inducing agents by targeting Bcl-2 protein.

Bcl-2, an anti-apoptotic protein, is a well-known and appealing cancer therapy target. Novel series of benzimidazole derivatives were synthesized and tested for their activity as Bcl-2 inhibitors on T98G glioblastoma, PC3 prostate, MCF-7 breast, and H69AR lung cancer cells. MTT assay was used to evaluate the cytotoxic effect. PI Annexin V Apoptosis Detection Kit was used to detect apoptosis. Expression levels of the Bcl-2 protein were examined by the Western blot analysis and qRT-PCR. All synthesized benzimidazole derivatives exhibited a cytotoxic effect on cancer cells with IC50 values in the range of 25.2-88.2µg/mL. Among all derivatives, compounds C1 and D1 demonstrated a higher cytotoxic effect on cancer cells with IC50 values < 50µg/mL, while a lower cytotoxic effect against human embryonic kidney cells with IC50 values of > 100µg/mL. C1 and D1 caused a significant increase in the percentage of apoptotic cells in all types of cancer cell cells and both Bcl-2 mRNA and protein levels were significantly reduced. These results suggest that the novel benzimidazole derivatives may be candidates for apoptosis-inducing agents in cancer treatment by targeting anti-Bcl-2 proteins in cancer cells.

Benzimidazole Derivatives as New Potential NLRP3 Inflammasome Inhibitors That Provide Neuroprotection in a Rodent Model of Neurodegeneration and Memory Impairment.

ObjectiveThe study investigated the effect of newly synthesized benzimidazole derivatives against ethanol-induced neurodegeneration. According to evidence, ethanol consumption may cause a severe insult to the central nervous system (CNS), resulting in mental retardation, neuronal degeneration, and oxidative stress. Targeting neuroinflammation and oxidative stress may be a useful strategy for preventing ethanol-induced neurodegeneration.MethodologyFirstly, the newly synthesized compounds were subjected to molecular simulation and docking in order to predict ligand binding status. Later, for in vivo observations, adult male Sprague Dawley rats were used for studying behavioral and oxidative stress markers. ELIZA kits were used to analyse tumour necrosis factor-alpha (TNF-), nuclear factor-B (NF-B), interleukin (IL-18), and pyrin domain-containing protein 3 (NLRP3) expression, while Western blotting was used to measure IL-1 and Caspase-1 expression.ResultsOur findings suggested that altered levels of antioxidant enzymes were associated with elevated levels of TNF-α, NF-B, IL-1, IL-18, Caspase-1, and NLRP3 in the ethanol-treated group. Furthermore, ethanol also caused memory impairment in rats, as measured by behavioural tests. Pretreatment using selected benzimidazole significantly increased the combat of the brain against ethanol-induced oxidative stress. The neuroprotective effects of benzimidazole derivatives were promoted by their free radical scavenging activity, augmentation of endogenous antioxidant proteins (GST, GSH), and amelioration of lipid peroxide (LPO) and other pro-inflammatory mediators. Molecular docking and molecular simulation studies further supported our hypothesis that the synthetic compounds Ca and Cb had an excellent binding affinity with proper bond formation with their targets (TNF-α and NLRP3).ConclusionIt is revealed that these benzimidazole derivatives can reduce ethanol-induced neuronal toxicity by regulating the expression of cytokines, antioxidant enzymes, and the inflammatory cascade.

A systematic review on diverse synthetic route and pharmacological activities of benzimidazole as optimized lead

The aim of this review is to provide the systematic information of synthetic scheme and biological activity of synthesized benzimidazole derivatives. Benzimidazole is widely used lead molecule for the synthesis of various types of pharmacologically active moiety. It is heterocyclic aromatic fused colorless solid having molecular mass of 118.053 g/mol. It is basic in nature and can be served as ligand in coordination chemistry. It is bioactive compound showed various pharmacological activity till now viz. anthelmintics (albendazole, mebendazole), proton pump inhibitors (omeprazole, pantoprazole), antibiotics, antiprotozoal, antifungal, anticancer, anti-viral, anti-oxidant, anti-inflammatory etc. Various synthetic route by various methods is also already reported. Some of them are traditional convenient method, microwave reactor method, solvent free synthesis method, green synthesis method. Due to its wide variety of biological action and the similarity with biomolecule, it is frequently taken as lead for new drug discovery

Microwave synthesized ionic liquids as green catalysts for the synthesis of benzimidazoles: Spectral and computational studies for potential anticancer activity

• Innovative, green chemical processes for solvent free, quicker, efficient reaction times & products i.e., MW & ILs. • Modifying conventional organic transformations with green catalysts (ILs) e. g. Benzimidazoles. • Identifying the possibility to develop benzimidazole derivatives as promising anti-breast cancer drugs. • As breast cancer mutant, oxidoreductase enzyme (3hb5) was used as a molecular docking target in this investigation. • Further, Ligand's and/or protein's surface proved to be a useful tool for lead optimization. Imidazolium based ionic liquid (IL) [bmim] Br or 1-butyl-3-methyl imidazolium bromide synthesized from 1-methyl imidazole and butyl bromide by microwave (MW) method and is used for efficient synthesis of benzimidazoles from o-phenylene diamine and aldehydes at room temperature (RT). Our attention has been drawn to the development of cost-effective and environmentally friendly catalytic systems for chemical synthesis because of the increasing need for greener and more sustainable technologies. This procedure has various benefits, including excellent yields (≈100%) of synthesized benzimidazole derivatives in 3 h and product recovery with minimal experimental work-up. The catalytic activity of ionic liquid can be recovered and reused up to four times without losing its activity. The 17 beta-hydroxysteroid dehydrogenase (PDB ID: 3hb5) was used as a target in a molecular docking study of these benzimidazole derivatives using Flare V5GUI software. They have the greatest LF dG score, ranging from −8.03 to −6.3 kcal/mol, indicating that these benzimidazole derivatives could be developed as promising anti-breast cancer drug candidates. Further, the electrostatic complementarity approach outlined here is a useful and versatile technique for drug development. The ability to observe EC values over the surface of a ligand or protein has a huge advantage when considered optimization.

Synthesis, DFT Molecular Geometry and Anticancer Activity of Symmetrical 2,2'-(2-Oxo-1H-benzo[d]imidazole-1,3(2H)-diyl) Diacetate and Its Arylideneacetohydrazide Derivatives.

To identify new candidate anticancer compounds, we here report the synthesis of benzimidazole derivatives: diethyl 2,2′-(2-oxo-1H-benzo[d]imidazole-1,3(2H)-diyl) diacetate and its arylideneacetohydrazide derivatives, using ultrasonic irradiation and conventional heating. The compounds were confirmed by Nuclear magnetic resonance (NMR) (JEOL, Tokyo, Japan) and Fourier transform infrared spectroscopy (FTIR) spectroscopy (Thermoscientific, Waltham, MA, USA). The molecular structure and electronic properties of the studied compounds were predicted for the acetohydrazide hydrazones. These compounds exist as a mixture of configurational and conformational isomerism as well as amido-amidic acid tautomerism. The NMR spectral data proved the predominance of syn-E amido isomers. In addition, density functional theory (DFT) predicted stability in the gas phase and showed that syn-E amido isomers are the most stable in the presence of an electron donating group, while the anti-isomer is the most stable in the presence of electron-attracting substituents. The anticancer activity of these synthetic compounds 6a, 6b and 6c towards both colon cancer (HCT-116) and cervical cancer (HeLa) cells was examined by MTT assay and DAPI staining. The MTT assay revealed a strong antiproliferative effect against the cancer cells at low concentrations, and interestingly, no significant inhibitory action against the non-cancerous cell line, HEK-293. The IC50 values for HCT-116 were 29.5 + 4.53 µM, 57.9 + 7.01 µM and 40.6 + 5.42 µM for 6a, 6b, and 6c, respectively. The IC50 values for HeLa cells were 57.1 + 6.7 µM, 65.6 + 6.63 µM and 33.8 + 3.54 µM for 6a, 6b, and 6c, respectively. DAPI staining revealed that these synthesized benzimidazole derivatives caused apoptotic cell death in both the colon and cervical cancer cells. Thus, these synthetic compounds demonstrate encouraging anticancer activity as well as being safe for normal human cells, making them attractive candidates as anticancer agents.

Novel benzimidazole derivatives; synthesis, bioactivity and molecular docking study as potent urease inhibitors.

Benzimidazole derivativesarewidelyusedtodesign andsynthesizenovel bioactive compounds.There are several approved benzimidazole-baseddrugsonthemarket. In this study, we aimed to design andsynthesizea series of novel benzimidazole derivatives 8a-nthatareurease inhibitors. All 8a-n were synthesized in a multistep. To determine the urease inhibitory effect of 8a-n, the urease inhibition kit was used. The cytotoxicity assay of 8a-n was determined using MTT method. Molecular modelling was determined using autodock software. All8a-n were synthesized in high yield, and their structures were determined using 1H-NMR, 13C-NMR, MS, and elemental analyses. In compared to thiourea and hydroxyurea as standards (IC50: 22 and 100µM, respectively), all 8a-n had stronger urease inhibition activity (IC50: 3.36-10.81µM). With an IC50 value of 3.36µM, 8e had the best enzyme inhibitory activity. On two evaluated cell lines, the MTT cytotoxicity experiment revealed that all 8a-n have IC50 values greater than 50µM. Finally, a docking investigation revealed a plausible way of interaction between the 8e and 8d and the enzyme's active site's key residues. The synthesized benzimidazole derivatives exhibit high activity, suggesting that further research on this family of compounds would be beneficial to finding a potent urease inhibitor.

Synthesis and Characterization of New benzimidazole-nitrone Derivatives and Study of Their Effect as Anti-fungal

New benzimidazole derivatives (benzimidazole-nitrone) were synthesized from the condensation of o-phenylene diamine with p-amino benzaldehyde in the presence of (P-TSOH\EtOH) then the benzimidazole compounds that containing an imine group were oxidized to obtain a nitrone group by used peracetic acid and identified by FT-IR, H1-NMR spectra, and elemental analysis. all compounds applied to the candida and aspergillus fungi gave a different result. The compounds have Ph, OH and N(CH3)2 groups as substituted in synthesized benzimidazole derivatives were showed reactivity as anti-fungal.

Synthesis, ADMET, drug likeness and in silico activities of benzimidazole derivative

In the current study, eleven derivatives of benzimidazole have been synthesized. The synthesis of the substituted derivatives was confirmed by FTIR and NMR analysis. 3-D Structure of enzyme of Cathepsin L-like proteinase of “Fasciola hepatica(Liver fluke)”(CLpfh) was attained from “Protein Data bank” the structure of synthesized benzimidazole derivatives were drawn using Chem Draw ultra 12.0 whereas ADMET predictions were done using DATA Warrior and Swiss ADME, the “molecular docking activity” of all the derivatives was tested using “AUTODOCK VINA” against designed “CLpfh”protein receptor. Docking experiments demonstrated a favorable interaction between produced compounds and “CLpfh”protein receptor with significant binding energy values. Further molecular dynamic simulation studies were also performed for most potent compound-protein complex using GROMACS.

Microwave assisted synthesis of benzimidazole derivatives using tetra butyl ammonium chloride as phase transfer catalyst, characterization, biological activities and molecular docking studies

Benzimidazole and its derivatives are of wide interest because of their diverse biological activity and clinical applications. The heterocyclic imidazole core is a common moiety in a large number of natural products and pharmacologically active compounds and because of that they are possessing inhibitory activity as well as favorable selectivity ratio. Benzimidazoles exhibit significant activities like anti-microbial, anti-viral, anti-diabetic, anti-cancer activity, numerous antioxidants, anti-parasitic, anti-helmintics, antiproliferative, anti-HIV, anti-convulsant, antiinflammatory, anti-hypertensive, anti-neoplastic, proton pump inhibitor and anti-trichinellosis. The synthesis of benzimidazole derivatives remains a focus of medicinal research. Here benzimidazole derivatives were synthesized using two phase system under microwave conditions using the phase transfer catalyst tetra butyl ammonium chloride (10% mol) in good yield. The molecular docking study against 4GQQ protein with synthesized benzimidazole derivatives was performed to see the necessary interactions responsible for anti-bacterial activity.

1H-benzimidazole-2-yl hydrazones as tubulin-targeting agents: Synthesis, structural characterization, anthelmintic activity and antiproliferative activity against MCF-7 breast carcinoma cells and molecular docking studies

In the present study, fifteen benzimidazolyl-2-hydrazones 7a-7o of fluoro-, hydroxy- and methoxy-substituted benzaldehydes and 1,3-benzodioxole-5-carbaldehyde were synthesized and their structure was identified by IR, NMR, and elemental analysis. The compounds 7j 2-(3-hydroxybenzylidene)-1-(5(6)-methyl-1H-benzimidazol-2-yl)hydrazone and 7i 2-(3-hydroxybenzylidene)-1-(1H-benzimidazol-2-yl)hydrazone have exerted the strongest anthelmintic activity (100% after 24 h incubation period at 37 °C) against isolated muscle larvae of Trichinella spiralis in an in vitro experiment. The in vitro cytotoxicity assay towards MCF-7 breast cancer cells and mouse embryo fibroblasts 3T3 showed that the studied benzimidazolyl-2-hydrazones exhibit low to moderate cytotoxic effects. The ability of the studied benzimidazolyl-2-hydrazones to modulate microtubule polymerization was confirmed and suggested that their anthelmintic action is mediated through inhibition of the tubulin polymerization likewise the other known benzimidazole anthelmitics. It was also shown that the four most promising benzimidazolyl-2-hydrazones do not affect significantly the AChE activity even at high tested concentration, thus indicating that they do not have the potential for neurotoxic effects. The binding mode of compounds 7j and 7n in the colchicine-binding site of tubulin were clarified by molecular docking simulations. Taken together, these results demonstrate that for the synthesized benzimidazole derivatives the anthelmintic activity against T. spiralis and the inhibition of tubulin polymerization are closely related.

Pharmacological Screening of Substituted Benzimidazole Derivatives

In the present study some substituted benzimidazole derivatives were screened for several biological activities. The synthesized compounds were subjected to evaluation of central analgesic, anti-inflammatory, cytotoxicity, antimicrobial and antioxidant activities by radiant heat induced tail flicking, carrageenan induced rat paw edema inhibition, brine shrimp lethality bioassay, disc diffusion and DPPH free radical scavenging methods, respectively. Compounds 2a, 2c and 2d elongated the tail flicking time by 58.07-, 51.59- and 76.65%, respectively (p &lt; 0.001) at 50 mg/kg body weight dose compared to the standard morphine (87.17%). Compounds 2b, 2c and 2d showed prominent anti-inflammatory activity at 100 mg/kg body weight dose (% of paw edema inhibition 81.75%, 79.09% and 86.69%, respectively) compared to the standard aceclofenac (87.83%). Among the synthesized benzimidazole derivatives, compounds 1a, 1b, 1c, 2a and 2d exhibited potent cytotoxicity with the IC50 values of 5.47-, 11.92-, 4.55-, 7.63- and 7.94 μg/ml, respectively. In addition, compounds 1c and 2d displayed mild to moderate zone of inhibition (8-12 mm). On the other hand, 1a and 1b showed very mild antioxidant activity with IC50 values of 12.25 × 103 μg/ml and 87.33 ×103 μg/ml. Among all the derivatives, 2c, 2d and 1c can be potential candidates for designing new analgesic, anti-inflammatory and anti-cancer agents in future.&#x0D; Dhaka Univ. J. Pharm. Sci. 20(1): 95-102, 2021 (June)

Corrosion Inhibition Potential of Ethanol Extract of Acacia nilotica Leaves on Mild Steel in an Acidic Medium

Corrosion Inhibition Potential of Ethanol Extract of Acacia nilotica Leaves on Mild Steel in an Acidic Medium

Synthesis and Evaluation of Analgesic and Antioxidant Activities of Substituted Benzimidazole Derivatives

The present study describes the synthesis and pharmacological evaluation of a number of substituted benzimidazole derivatives designated by 3A-1, 3A-2, 3A-3, 3B-1 and 3B-2 through condensation of different o-aryldiamine compounds with the corresponding aldehyde employing ammonium salt as a catalyst. All the compounds were characterized by IR and 1H NMR spectroscopic analysis. The synthesized benzimidazole derivatives were investigated for analgesic and antioxidant activities using acetic acid-induced writhing inhibition in Swiss albino mice and DPPH free radical scavenging assay, respectively. Compounds 3A-3, 3B-1 and 3B-2 at a dose of 50 mg/kg body weight reduced the number of writhings by 88.24%, 84.03% and 85.71%, respectively (p&lt;0.001) in comparison with standard diclofenac (90.76% inhibition). The derivatives 3A-1, 3A-2, 3A-3 and 3B-2 showed prominent antioxidant activity with IC50 values of 0.038, 0.959, 8.834 and 7.519 μg/ml, respectively in comparison with the standard butylated hydroxytoluene (BHT) (14.44 μg/ml). Among the synthesized compounds, 3A-3 and 3B- 2 emerged as the most promising analgesic and antioxidant agents and expressed their potential as lead compounds in future research.&#x0D; Dhaka Univ. J. Pharm. Sci. 19(1): 37-46, 2020 (June)