Benzimidazole derivatives as new α-glucosidase inhibitors and in silico studies

Coumarin linked to 2-phenylbenzimidazole derivatives as potent α-glucosidase inhibitors

α-Glucosidase inhibitors have emerged as crucial agents in the management of type 2 diabetes mellitus. In the present study, a new series of coumarin-linked 2-phenylbenzimidazole derivatives 5a-m was designed, synthesized, and evaluated as anti-α-glucosidase agents. Among these derivatives, compound 5k (IC50 = 10.8 µM) exhibited a significant inhibitory activity in comparison to the positive control acarbose (IC50 = 750.0 µM). Through kinetic analysis, it was revealed that compound 5k exhibited a competitive inhibition pattern against α-glucosidase. To gain insights into the interactions between the title compounds and α-glucosidase molecular docking was employed. The obtained results highlighted crucial interactions that contribute to the inhibitory activities of the compounds against α-glucosidase. These derivatives show immense potential as promising starting points for developing novel α-glucosidase inhibitors.

A Review on the Development of Novel Heterocycles as α-Glucosidase Inhibitors for the Treatment of Type-2 Diabetes Mellitus

One of the most effective therapeutic decencies in the treatment of Type 2 Diabetes Mellitus is the inhibition of α-glucosidase enzyme, which is present at the brush border of the intestine and plays an important role in carbohydrate digestion to form mono-, di-, and polysaccharides. Acarbose, Voglibose, Miglitol, and Erniglitate have been well-known α-glucosidase inhibitors in science since 1990. However, the long synthetic route and side effects of these inhibitors forced the researchers to move their focus to innovate simple and small heterocyclic scaffolds that work as excellent α-glucosidase inhibitors. Moreover, they are also effective against the postprandial hyperglycemic condition in Type 2 Diabetes Mellitus. In this aspect, this review summarizes recent progress in the discovery and development of heterocyclic molecules that have been appraised to show outstanding inhibition of α-glucosidase to yield positive effects against diabetes.

Design, synthesis, in vitro, and in silico evaluations of benzo[d]imidazole-amide-1,2,3-triazole-N-arylacetamide hybrids as new antidiabetic agents targeting α-glucosidase

α-Glucosidase as a carbohydrate-hydrolase enzyme is a crucial therapeutic target for type 2 diabetes. In this work, benzo[d]imidazole-amide containing 1,2,3-triazole-N-arylacetamide derivatives 8a-n were synthesized and evaluated for their inhibitory activity against α-glucosidase. In vitro α-glucosidase inhibition assay demonstrated that more than half of the title compounds with IC₅₀ values in the range of 49.0-668.5 μM were more potent than standard inhibitor acarbose (IC₅₀ = 750.0 µM). The most promising inhibitor was N-2-methylphenylacetamid derivative 8c. Kinetic study revealed that compound 8c (K_i = 40.0 µM) is a competitive inhibitor against α-glucosidase. Significantly, molecular docking and molecular dynamics studies on the most potent compound showed that this compound with a proper binding energy interacted with important amino acids of the α-glucosidase active site. Study on cytotoxicity of the most potent compounds 8c, 8e, and 8g demonstrated that these compounds did not show cytotoxic activity against the cancer and normal cell lines MCF-7 and HDF, respectively. Furthermore, the ADMET study predicted that compound 8c is likely to be orally active and non-cytotoxic.

Synthesis, in vitro biological assessment, and molecular docking study of benzimidazole-based thiadiazole derivatives as dual inhibitors of α-amylase and α-glucosidase

The clinical significance of benzimidazole-containing drugs has increased in the current study, making them more effective scaffolds. These moieties have attracted strong research interest due to their diverse biological features. To examine their various biological significances, several research synthetic methodologies have recently been established for the synthesis of benzimidazole analogs. The present study aimed to efficiently and quickly synthesize a new series of benzimidazole analogs. Numerous spectroscopic techniques, including ¹H-NMR, ¹³C-NMR, and HREI-MS, were used to confirm the synthesized compounds. To explore the inhibitory activity of the analogs against α-amylase and α-glucosidase, all derivatives (1-17) were assessed for their biological potential. Compared to the reference drug acarbose (IC₅₀ = 8.24 ± 0.08 µM), almost all the derivatives showed promising activity. Among the tested series, analog 2 (IC₅₀ = 1.10 ± 0.10 & 2.10 ± 0.10 µM, respectively) displayed better inhibitory activity. Following a thorough examination of the various substitution effects on the inhibitory capacity of α-amylase and α-glucosidase, the structure-activity relationship (SAR) was determined. We looked at the potential mechanism of how active substances interact with the catalytic cavity of the targeted enzymes in response to the experimental results of the anti-glucosidase and anti-amylase. Molecular docking provided us with information on the interactions that the active substances had with the various amino acid residues of the targeted enzymes for this purpose.

Synthesis and structure-activity relationship studies of benzimidazole-thioquinoline derivatives as α-glucosidase inhibitors

In this article, different s-substituted benzimidazole-thioquinoline derivatives were designed, synthesized, and evaluated for their possible α-glucosidase inhibitory activities. The most active compound in this series, 6j (X = 4-bromobenzyl) exhibited significant potency with an IC₅₀ value of 28.0 ± 0.6 µM compared to acarbose as the positive control with an IC₅₀ value of 750.0 µM. The kinetic study showed a competitive inhibition pattern against α-glucosidase for the 6j derivative. Also, the molecular dynamic simulations were performed to determine key interactions between compounds and the targeted enzyme. The in silico pharmacodynamics and ADMET properties were executed to illustrate the druggability of the novel derivatives. In general, it can be concluded that these derivatives can serve as promising leads to the design of potential α-glucosidase inhibitors.

Chromone-based benzohydrazide derivatives as potential α-glucosidase inhibitor: Synthesis, biological evaluation and molecular docking study

In order to find new α-glucosidase inhibitors with high efficiency and low toxicity, novel chromone-based benzohydrazide derivatives 6a-6s were synthesized and characterized through ¹H NMR, ¹³C NMR, and HRMS. All the new synthesized compounds were tested for inhibitory activities against α-glucosidase. Compounds 6a-6s with IC₅₀ values ranging from 4.51 ± 0.09 to 27.21 ± 0.83 μM, showed a potential α-glucosidase inhibitory activity as compared to the positive control (acarbose: IC₅₀ = 790.40 ± 0.91 μM). Compound 6i exhibited the highest α-glucosidase inhibitory activity with an IC₅₀ value of 4.51 ± 0.09 μM. Theinteractionbetween α-glucosidase and 6i was further confirmed by enzyme kinetic, fluorescence quenching, circular dichroism, and molecular docking study. In vivo experiment showed that 6i could suppress the rise of blood glucose levels after sucrose loading. The cytotoxicity result indicated that 6i exhibited low cytotoxicity in vitro.

2,5-Disubstituted furan derivatives containing imidazole, triazole or tetrazole moiety as potent α-glucosidase inhibitors

α-Glucosidase inhibitors (AGIs) are oral antidiabetic drugs, preferably used in treating type 2 diabetes mellitus, that delay the absorption of carbohydrates from the gastrointestinal system. In this work, 2,5-disubstituted furan derivatives containing imidazole, triazole or tetrazole moiety (III-01 ∼ III-45) were synthesized and characterized by elemental analysis, HRMS, ¹H NMR, ¹³C NMR and single crystal X-ray. Their inhibitory activity against α-glucosidase was screened. The most promising inhibitors were compound III-11 (IC₅₀ = 6.0 ± 1.1 μM), III-16 (IC₅₀ = 2.2 ± 0.2 μM) and III-39 (IC₅₀ = 4.6 ± 1.9 μM), respectively. Kinetic study revealed that compounds III-11 and III-39 were uncompetitive inhibitors against α-glucosidase. Meanwhile, III-16 (Ki = 5.1 ± 0.7 μM) was a competitive inhibitor. Furthermore, molecular docking studies indicated that the existence of the azole group played a critically important role in hydrogen bond interaction with α-glucosidase. Significantly, in vivo toxicity towards HEK293 cells, RAW264.7 cells and HepG2 cells suggested that compounds III-11 and III-39 possessed non-toxicity, that could be considered as potential candidates for further development of novel antidiabetic drugs.

Synthesis of Novel N-Methylmorpholine-Substituted Benzimidazolium Salts as Potential α-Glucosidase Inhibitors

The α-glucosidase enzyme, located in the brush border of the small intestine, is responsible for overall glycemic control in the body. It hydrolyses the 1,4-linkage in the carbohydrates to form blood-absorbable monosaccharides that ultimately increase the blood glucose level. α-Glucosidase inhibitors (AGIs) can reduce hydrolytic activity and help to control type 2 diabetes. Aiming to achieve this, a novel series of 1-benzyl-3-((2-substitutedphenyl)amino)-2-oxoethyl)-2-(morpholinomethyl)-1H-benzimidazol-3-ium chloride was synthesized and screened for its α-glucosidase inhibitory potential. Compounds 5d, 5f, 5g, 5h and 5k exhibited better α-glucosidase inhibitions compared to the standard drug (acarbose IC50 = 58.8 ± 0.012 µM) with IC50 values of 15 ± 0.030, 19 ± 0.060, 25 ± 0.106, 21 ± 0.07 and 26 ± 0.035 µM, respectively. Furthermore, the molecular docking studies explored the mechanism of enzyme inhibitions by different 1,2,3-trisubstituted benzimidazolium salts via significant ligand–receptor interactions.

Design, synthesis, in vitro, and in silico enzymatic evaluations of thieno[2,3-b]quinoline-hydrazones as novel inhibitors for α-glucosidase

In the development of novel anti-α-glucosidase agents, we synthesized novel thieno[2,3-b]quinoline-hydrazones 9a-n by facile and efficient conventional chemical reactions. These compounds were characterized by IR, ¹H NMR, ¹³C NMR, and elemental analysis. Inhibitory activities of the title compounds were evaluated against yeast α-glucosidase. In particular, compounds 9c, 9d, and 9h exhibited high anti-α-glucosidase activity. Representatively, compound 9c with IC₅₀ = 1.3 µM, was 576-times more potent than positive control acarbose. Molecular docking study of the most active compounds showed that these compounds formed important binding interactions at α-glucosidase active site. Molecular dynamics study of compound 9c was also performed and the obtained results were compared with acarbose. Compounds 9c, 9d, and 9h were also evaluated for in silico druglikeness properties and ADMET prediction. These studies showed that the title most potent compounds could be exploited as drug candidates.

Cyanoacetohydrazide linked to 1,2,3-triazole derivatives: a new class of α-glucosidase inhibitors

In this work, a novel series of cyanoacetohydrazide linked to 1,2,3-triazoles (9a–n) were designed and synthesized to be evaluated for their anti-α-glucosidase activity, focusing on the fact that α-glucosidase inhibitors have played a significant role in the management of type 2 diabetes mellitus. All synthesized compounds except 9a exhibited excellent inhibitory potential, with IC50 values ranging from 1.00 ± 0.01 to 271.17 ± 0.30 μM when compared to the standard drug acarbose (IC50 = 754.1 ± 0.5 μM). The kinetic binding study indicated that the most active derivatives 9b (IC50 = 1.50 ± 0.01 μM) and 9e (IC50 = 1.00 ± 0.01 μM) behaved as the uncompetitive inhibitors of α-glucosidase with Ki = 0.43 and 0.24 μM, respectively. Moreover, fluorescence measurements were conducted to show conformational changes of the enzyme after binding of the most potent inhibitor (9e). Calculation of standard enthalpy (ΔHm°) and entropy (ΔSm°) values confirmed the construction of hydrophobic interactions between 9e and the enzyme. Also, docking studies indicated desired interactions with important residues of the enzyme which rationalized the in vitro results.

Identification of Cyclic Sulfonamides with an N-Arylacetamide Group as α-Glucosidase and α-Amylase Inhibitors: Biological Evaluation and Molecular Modeling

Diabetes mellitus (DM), a complicated metabolic disorder, is due to insensitivity to insulin function or reduction in insulin secretion, which results in postprandial hyperglycemia. α-Glucosidase inhibitors (AGIs) and α-amylase inhibitors (AAIs) block the function of digestive enzymes, which delays the carbohydrate hydrolysis process and ultimately helps to control the postprandial hyperglycemia. Diversified 2-(3-(3-methoxybenzoyl)-4-hydroxy-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl)-N-arylacetamides were synthesized and evaluated for their in vitro inhibitory potential against α-glucosidase and α-amylase enzymes. The compounds with chloro, bromo and methyl substituents demonstrated good inhibition of α-glucosidase enzymes having IC50 values in the range of 25.88-46.25 μM, which are less than the standard drug, acarbose (IC50 = 58.8 μM). Similarly, some derivatives having chloro, bromo and nitro substituents were observed potent inhibitors of α-amylase enzyme, with IC50 values of 7.52 to 15.06 μM, lower than acarbose (IC50 = 17.0 μM). In addition, the most potent compound, N-(4-bromophenyl)-2-(4-hydroxy-3-(3-methoxybenzoyl)-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl)acetamide (12i), was found to be a non-competitive and competitive inhibitor of α-glucosidase and α-amylase enzymes, respectively, during kinetic studies. The molecular docking studies provided the binding modes of active compounds and the molecular dynamics simulation studies of compound 12i in complex with α-amylase also showed that the compound is binding in a fashion similar to that predicted by molecular docking studies.

Selenourea and thiourea derivatives of chiral and achiral enetetramines: Synthesis, characterization and enzyme inhibitory properties

A series of chiral and achiral cyclic seleno- and thiourea compounds bearing benzyl groups on N-atoms were prepared from enetetramines and appropriate Group VI elements in good yields. All the synthesized compounds were characterized by elemental analysis, FT-IR, ¹H NMR and ¹³C NMR spectroscopy, and the molecular and crystal structures of (R,R)-4b and (R,R)-5b were confirmed by the single-crystal X-ray diffraction method. These assayed for their activities against metabolic enzymes acetylcholinesterase, butyrylcholinesterase, and α-glycosidase. These selenourea and thiourea derivatives of chiral and achiral enetetramines effectively inhibit AChE and BChE with IC₅₀ values in the range of 3.32-11.36 and 1.47-9.73 µM, respectively. Also, these compounds inhibited α-glycosidase enzyme with IC₅₀ values varying between 1.37 and 8.53 µM. The results indicated that all the synthesized compounds exhibited excellent inhibitory activities against mentioned enzymes as compared with standard inhibitors. Representatively, the most potent compound against α-glycosidase enzyme, (S,S)-5b, was 12-times more potent than standard inhibitor acarbose; 7b and 8a as most potent compounds against cholinesterase enzymes, were around 5 and 13-times more potent than standard inhibitor tacrine against achethylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively.

Design, synthesis and biological evaluation of novel (E)-2-benzylidene-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)hydrazine-1-carboxamide derivatives as α-glucosidase inhibitors

In this present study, a series of novel (E)-2-benzylidene-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)hydrazine-1-carboxamide derivatives against α-glucosidase were designed and synthesized, and their biological activities were evaluated in vitro and in vivo. Most of the designed analogues exhibited better inhibitory activity than the marketed acarbose, especially the most potent compound 7 with an IC₅₀ value of 9.26 ± 1.84 μM. The direct binding of 7 and 8 with α-glucosidase was confirmed by fluorescence quenching experiments, and the kinetic and molecular docking studies revealed that 7 and 8 inhibited α-glucosidase in a non-competitive manner. Cytotoxicity bioassay indicated compounds 7 and 8 were non-toxic towards LO2 and HepG2 at 100 μM. Furthermore, both compounds were demonstrated to have in vivo hypoglycemic activity by reducing the blood glucose levels in sucrose-treated rats.

3-Alkenyl-2-oxindoles: Synthesis, antiproliferative and antiviral properties against SARS-CoV-2

Sets of 3-alkenyl-2-oxindoles (6,10,13) were synthesized in a facile synthetic pathway through acid dehydration (EtOH/HCl) of the corresponding 3-hydroxy-2-oxoindolines (5,9,12). Single crystal (10a,c) and powder (12a,26f) X-ray studies supported the structures. Compounds 6c and 10b are the most effective agents synthesized (about 3.4, 3.3 folds, respectively) against PaCa2 (pancreatic) cancer cell line relative to the standard reference used (Sunitinib). Additionally, compound 10b reveals antiproliferative properties against MCF7 (breast) cancer cell with IC₅₀ close to that of Sunitinib. CAM testing reveals that compounds 6 and 10 demonstrated qualitative and quantitative decreases in blood vessel count and diameter with efficacy comparable to that of Sunitinib, supporting their anti-angiogenic properties. Kinase inhibitory properties support their multi-targeted inhibitory activities against VEGFR-2 and c-kit in similar behavior to that of Sunitinib. Cell cycle analysis studies utilizing MCF7 exhibit that compound 6b arrests the cell cycle at G1/S phase while, 10b reveals accumulation of the tested cell at S phase. Compounds 6a and 10b reveal potent antiviral properties against SARS-CoV-2 with high selectivity index relative to the standards (hydroxychloroquine, chloroquine). Safe profile of the potent synthesized agents, against normal cells (VERO-E6, RPE1), support the possible development of better hits based on the attained observations.

Synthesis and α-Glucosidase Inhibition Activity of 2-[3-(Benzoyl/4-bromobenzoyl)-4-hydroxy-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl]-N-arylacetamides: An In Silico and Biochemical Approach

Diabetes mellitus (DM) is a chronic disorder and has affected a large number of people worldwide. Insufficient insulin production causes an increase in blood glucose level that results in DM. To lower the blood glucose level, various drugs are employed that block the activity of the α-glucosidase enzyme, which is considered responsible for the breakdown of polysaccharides into monosaccharides leading to an increase in the intestinal blood glucose level. We have synthesized novel 2-(3-(benzoyl/4-bromobenzoyl)-4-hydroxy-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl)-N-arylacetamides and have screened them for their in silico and in vitro α-glucosidase inhibition activity. The derivatives 11c, 12a, 12d, 12e, and 12g emerged as potent inhibitors of the α-glucosidase enzyme. These compounds exhibited good docking scores and excellent binding interactions with the selected residues (Asp203, Asp542, Asp327, His600, Arg526) during in silico screening. Similarly, these compounds also showed good in vitro α-glucosidase inhibitions with IC₅₀ values of 30.65, 18.25, 20.76, 35.14, and 24.24 μM, respectively, which were better than the standard drug, acarbose (IC₅₀ = 58.8 μM). Furthermore, a good agreement was observed between in silico and in vitro modes of study.

Recent advancements on Benzimidazole: A versatile scaffold in medicinal chemistry

Benzimidazole is nitrogen containing fused heterocycle which has been extensively explored in medicinal chemistry. Benzimidizole nucleus has been found to possess various biological activities such as anticancer, antimicrobial, anti-inflammatory, antiviral, antitubercular and antidiabetic. A number of benzimidazoles such as bendamustine, pantoprazole have been approved for the treatment of various illnesses whereas galeterone and GSK461364 are in clinical trials. The present review article gives an overview about the different biological activities exhibited by the benzimidazole derivatives as well as different methods used for the synthesis of benzimidazole derivatives for the past ten years.

In silico study of garlic (Allium sativum L.)-derived compounds molecular interactions with α-glucosidase

Diabetes mellitus is a metabolic syndrome characterized by elevated blood glucose. The α-glucosidase enzyme is responsible for the hydrolysis of carbohydrates. This in silico study aimed to evaluate the inhibitory effects of the isolated compounds from Allium sativum L. on α-glucosidase. At first, sulfur and phenolic compounds of A. sativum L. were obtained from PubChem database, and α-glucosidase enzyme structure was obtained from Protein Data Bank. Toxicity class of compounds and the Lipinski parameter were predicted by Toxtree and Protox II and the Swiss ADME tools, respectively. Finally, the molecular interaction analysis between α-glucosidase and compounds from A. sativum L. was performed by AutoDock 4.2.6. Molecular interactions were investigated using Discovery Studio Visulizer and Ligplot 2.1 program. All of the selected sulfur and phenolic compounds from A. sativum L. followed the Lipinski's rules, had an acceptable binding energy, and lacked toxicity; therefore, they were appropriate candidates for α-glucosidase inhibition. Among these compounds, methionol and caffeic acid showed the lowest binding energy, and the highest inhibitory effect on α-glucosidase enzyme with - 3.9 and - 4.8 kcal/mol, respectively. These compounds also indicated the lower binding energy than the standard inhibitor (miglitol). Among the sulfur and phenolic compounds in A. sativum L., methionol and caffeic acid were predicted to be the powerful inhibitors, due to having more hydrogen binds and hydrophobic interactions with the active site of α-glucosidase.

Recent Advances in Therapeutic Applications of Bisbenzimidazoles

Nitrogen-containing heterocycles are one of the most common structural motifs in approximately 80% of the marketed drugs. Of these, benzimidazoles analogues are known to elicit a wide spectrum of pharmaceutical activities such as anticancer, antibacterial, antiparasitic, antiviral, antifungal as well as chemosensor effect. Based on the benzimidazole core fused heterocyclic compounds, crescent-shaped bisbenzimidazoles were developed which provided an early breakthrough in the sequence-specific DNA recognition. Over the years, a number of functional variations in the bisbenzimidazole core have led to the emergence of their unique properties and established them as versatile ligands against several classes of pathogens. The present review provides an overview of diverse pharmacological activities of the bisbenzimidazole analogues in the past decade with a brief account of its development through the years.

Synthesis of Benzimidazole-Based Analogs as Anti Alzheimer's Disease Compounds and Their Molecular Docking Studies

We synthesized 10 analogs of benzimidazole-based thiosemicarbazide 1 (a-j) and 13 benzimidazole-based Schiff bases 2 (a-m), and characterized by various spectroscopic techniques and evaluated in vitro for acetylcholinesterase (AchE) and butyrylcholinesterase (BchE) inhibition activities. All the synthesized analogs showed varying degrees of acetylcholinesterase and butyrylcholinesterase inhibitory potentials in comparison to the standard drug (IC₅₀ = 0.016 and 4.5 µM. Amongst these analogs 1 (a-j), compounds 1b, 1c, and 1g having IC₅₀ values 1.30, 0.60, and 2.40 µM, respectively, showed good acetylcholinesterase inhibition when compared with the standard. These compounds also showed moderate butyrylcholinesterase inhibition having IC₅₀ values of 2.40, 1.50, and 2.40 µM, respectively. The rest of the compounds of this series also showed moderate to weak inhibition. While amongst the second series of analogs 2 (a-m), compounds 2c, 2e, and 2h having IC₅₀ values of 1.50, 0.60, and 0.90 µM, respectively, showed moderate acetylcholinesterase inhibition when compared to donepezil. Structure Aactivity Relation of both synthesized series has been carried out. The binding interactions between the synthesized analogs and the enzymes were identified through molecular docking simulations.

In-Vitro Evaluation of Antioxidant, Antiproliferative and Photo-Protective Activities of Benzimidazolehydrazone Derivatives

In the search of multifunctional compounds we designed benzimidazole derivatives endowed with phenolic hydroxy groups and a hydrazone moiety as potential radical-scavenger and the antioxidant agents. The target molecules have been prepared by a simple synthetic procedure and tested for their antioxidant activity by DPPH, FRAP, and ORAC test, for photoprotective activity against UV rays and for antiproliferative activity against Colo-38 melanoma cells. Furthermore, two different dermocosmetic formulations were prepared with the compounds endowed with the best antioxidant and photoprotective profile and their release from formulation evaluated using Franz Cells system. High antioxidant activity is related to the presence of at least two hydroxy groups on arylidene moiety of benzimidazoles. Structure activity analysis revealed that the position of hydroxy groups is crucial for antioxidant activity as well as the presence of a 2-hydroxy-4-(diethylamino)arylidene group. The same correlation pattern was found to be related to photoprotective activity resulting in an UVA Protection Factor better than the commercial solar filter PBSA and antiproliferative activity against melanoma cells without producing cytotoxicity on normal keratinocytes. The release analysis indicated that high antioxidant activities are achieved with limited release at concentration compatible with the use as UV sunscreen filter.

Benzimidazole Containing Acetamide Derivatives Attenuate Neuroinflammation and Oxidative Stress in Ethanol-Induced Neurodegeneration

Oxidative stress-induced neuroinflammation is the prominent feature of neurodegenerative disorders, and is characterized by a gradual decline of structure and function of neurons. Many biochemical events emerge thanks to the result of this neurodegeneration, and ultimately provoke neuroinflammation, activation of microglia, and oxidative stress, leading to neuronal death. This cascade not only explains the complexity of events taking place across different stages, but also depicts the need for more effective therapeutic agents. The present study was designed to investigate the neuroprotective effects of newly synthesized benzimidazole containing acetamide derivatives, 3a (2-(4-methoxyanilino)-N-[1-(4-methylbenzene-1-sulfonyl)-1H-benzimidazol-2-yl] acetamide) and 3b (2-(Dodecylamino)-N-[1-(4-methylbenzene-1-sulfonyl)-1H-benzimidazol-2-yl] acetamide) against ethanol-induced neurodegeneration in the rat model. Both derivatives were characterized spectroscopically by proton NMR (¹H-NMR) and carbon-13 NMR (¹³C-NMR) and evaluated for neuroprotective potential using different pharmacological approaches. In vivo experiments demonstrated that ethanol triggered neurodegeneration characterized by impaired antioxidant enzymes and elevated oxidative stress. Furthermore, ethanol administration induced neuroinflammation, as demonstrated by elevated expression of tumor necrotic factor (TNF-α), nuclear factor κB (NF-κB), cyclooxygenase-2 (COX2), and ionized calcium-binding adapter molecule-1 (Iba-1), which was further validated by enzyme-linked immunosorbent assay (ELISA). Treatment with 3a and 3b ameliorated the ethanol-induced oxidative stress, neuroinflammation, and memory impairment. The affinity of synthesized derivatives towards various receptors involved in neurodegeneration was assessed through docking analysis. The versatile nature of benzimidazole nucleus and its affinity toward several receptors suggested that it could be a multistep targeting neuroprotectant. As repetitive clinical trials of neuroprotectants targeting a single step of the pathological process have failed previously, our results suggested that a neuroprotective strategy of acting at different stages may be more advantageous to intervene in the vicious cycles of neuroinflammation.

Biological Evaluation, Molecular Docking, and SAR Studies of Novel 2-(2,4-Dihydroxyphenyl)-1H- Benzimidazole Analogues

In the present study, new 4-(1H-benzimidazol-2-yl)-benzene-1,3-diols, modified in both rings, have been synthesized and their efficacies as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors have been determined. The modified Ellman’s spectrophotometric method was applied for the biological evaluation. The compounds showed strong (IC₅₀ 80–90 nM) AChE and moderate (IC₅₀ 5–0.2 µM) BuChE inhibition in vitro. Some compounds were effective toward AChE/BuChE, exhibiting high selectivity ratios versus BuChE, while the other compounds were active against both enzymes. The structure–activity relationships were discussed. The compounds inhibited also in vitro self-induced Aβ(1–42) aggregation and exhibited antioxidant properties. The docking simulations showed that the benzimidazoles under consideration interact mainly with the catalytic site of AChE and mimic the binding mode of tacrine.

Mutagenic Study of Benzimidazole Derivatives with (+S9) and without (-S9) Metabolic Activation

Benzimidazole derivatives have a diverse range of biological activities, including antiulcer, antihypertensive, antiviral, antifungal, anti-inflammatory, and anticancer. Despite these activities, previous studies have revealed that some of the derivatives can induce mutations. This study aimed to screen for potential mutagenic activities of novel benzimidazole derivatives 1–4 using the Ames test and to study their structure–activity relationship (SAR). An Ames test was carried out on two strains of Salmonella typhimurium (TA98 and TA100) in the absence and presence of metabolic activation. Genetic analysis was performed prior to the Ames test to determine the genotypes of the bacterial tester strains. Both bacterial strains showed dependency on histidine with the presence of rfa mutation, uvrB deletion, and plasmid pKM101. Further, all derivatives tested showed no mutagenic activity in the absence of metabolic activation in both tester strains. However, in the presence of metabolic activation, compound 1 appeared to induce mutation at 2.5 µg/plate when tested against the TA98 strain. These results suggest that the absence of the -OH group at the ortho-position over the phenyl ring might be the cause of increased mutagenic activity in compound 1. Additionally, the presence of mutagenic activity in compound 1 when it was metabolically activated indicates that this compound is a promutagen.

Synthesis of benzothiazole derivatives as a potent α-glucosidase inhibitor

Diabetes is one of the pre-dominant metabolic disorders all over the world. It is the prime reason of mortality and morbidity due to hyperglycemia which is link with numerus obstacles. Delaying absorption and digestion of carbohydrate has great therapeutic impact for governing postprandial hyperglycemia. Consequently, alpha glucosidase is one of the potential therapeutic approaches that reduce absorption of glucose and delay carbohydrate digestion hence maintaining blood glucose level. In this regard we have synthesized benzothiazole based oxadiazole in search of potent anti-diabetic agent as α-glucosidase Inhibitors. Benzothiazole based oxadiazole derivatives 1-23 have been synthesized, characterized by ¹HNMR, ¹³CNMR, and MS and evaluated for α-glucosidase Inhibition. All analogs exhibited a varying degree of α-glucosidase inhibitory activity with IC₅₀ values ranging in between 0.5 ± 0.01-30.90 ± 0.70 μM when compared with the standard acarbose (IC₅₀ = 866.30 ± 3.20 μM). Structure activity relationship has been established for all compounds. Molecular docking studies were performed to predict the binding interaction of the compounds with the active site of enzyme.

Efficient Synthesis and in Silico Studies of the Benzimidazole Hybrid Scaffold with the Quinolinyloxadiazole Skeleton with Potential α-Glucosidase Inhibitory, Anticoagulant, and Antiplatelet Activities for Type-II Diabetes Mellitus Management and Treating Thrombotic Disorders

The current study evaluates antidiabetic, anticoagulant, and antiplatelet activity of novel benzimidazole-containing quinolinyl oxadiazoles. These derivatives are synthesized and characterized using spectroscopy (FT-IR, ¹H NMR, and mass spectroscopy) and single-crystal X-ray diffraction methods. The inhibitory effects of these compounds were evaluated by the α-glucosidase inhibitory assay and shows the activity in the range of IC₅₀ = 0.66 ± 0.05 to 3.79 ± 0.46 μg/mL. In addition, molecular docking studies revealed that benzimidazole-containing quinolinyl oxadiazoles can correctly dock into the target receptor protein of the human intestinal α-glucosidase, while their bioavailability/drug-likeness was predicted to be acceptable but requires further optimization. On the other hand, compound 8a and 8d showed anticoagulant activity as they enhanced the clotting time from control 180-410 and 180-390 s, respectively, in platelet rich plasma and 230-460 and 230-545 s in platelet poor plasma. Furthermore, only 8a showed antiplatelet activity by inhibiting epinephrine-induced platelet aggregation, and the observed aggregation inhibition was found to be 93.4%. Compounds 8a-f show nontoxic properties because of the non-hydrolyzing properties in the RBC cells. In addition, 8a and 8d show anti-edema and anti-hemorrhagic properties in the experimental mice. These findings reveal that benzimidazole-containing quinolinyl oxadiazoles act as α-glucosidase inhibitors to develop novel therapeutics for treating type-II diabetes mellitus and can act as lead molecules in drug discovery as potential antidiabetic and antithrombotic agents.