Synthesis,biological evaluation and molecular docking studies of novel benzimidazole derivatives

A novel series of N-substituted-benzimidazolyl linked para substituted benzylidene based molecules containing three pharmacologically potent hydrogen bonding parts namely; 2,4-thiazolidinedione (TZD: a 2,4-dicarbonyl), diethyl malonate (DEM: a 1,3-diester and an isooxazolidinedione analog) and methyl acetoacetate (MAA: a β-ketoester) (6a–11b) were synthesized and evaluated for in vitro α-glucosidase inhibition. The structure of the novel synthesized compounds was confirmed through the spectral studies (LC–MS, ¹H NMR, ¹³C NMR, FT-IR). Comparative evaluation of these compounds revealed that the compound 9b showed maximum inhibitory potential against α-amylase and α-glucosidase giving an IC₅₀ value of 0.54 ± 0.01 μM. Furthermore, binding affinities in terms of G score values and hydrogen bond interactions between all the synthesized compounds and the AA residues in the active site of the protein (PDB code: 3TOP) to that of Acarbose (standard drug) were explored with the help of molecular docking studies. Compound 9b was considered as promising candidate of this series.     

Design,synthesis, biological evaluation and in silico studies of novel 1,2,3-triazole linked benzoxazine-2,4-dione conjugates as potent antimicrobial,antioxidant and anti-inflammatory agents

In an attempt to rationalize the search for new potential anti-inflammatory and anti-infection agents, a new series of 1,4-and 1,5-disubstituted 1,2,3-triazoles linked benzoxazine conjugates have been synthesized via “Click Chemistry” reaction, were designed, synthesized and characterized by means of spectral and elemental data. The newly synthesized compounds have been assessed for their antimicrobial, antioxidant and anti-inflammatory potential. Results revealed that all synthesized compounds display superior activities to the standard drug against different bacterial strains especially S. aureus, M. luteus, and P. aeruginosa, with good to moderate activity towards the tested E. coli bacteria, in respect to the commercial antibiotic, tetracycline. Moreover, the antifungal activity was screened against C. albicans and C. krusei yeasts and results demonstrate potent activity as compared to the standard drug, ampicillin. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assays, whose results indicate that analogues 4a (IC₅₀ 1.88 ± 0.07 µM and 2.17 ± 0.02) followed by 4b (IC₅₀ 2.19 ± 0.09 µM and 2.38 ± 0.43 µM), 4d (IC₅₀ 2.30 ± 0.01 µM and 4.07 ± 0.57 µM), and 4f (2.98 ± 0.02 µM and 3.80 ± 0.01 µM), respectively, exhibited the strongest activity when compared to the standard reference, butylated hydroxytoluene (BHT) (3.52 ± 0.08 µM and 4.64 ± 0.11 µM). In addition, their anti-inflammatory activity was assessed using the xylene-induced ear edema standard technique and the results demonstrated the potency of 4a, 4b and 4d as excellent anti-inflammatory agents. Preliminary structure–activity relationship studies (SARs) provide those biological activities can be modulated by the presence of unsubstituted aromatic ring as well as the position of substituents on the phenyl moiety via electron withdrawing groups (EWGs) or electron donating groups (EDGs) effects. Docking studies on the most promising compounds 4a, 4b, and 4d into the active sites of S. aureus tyrosyl-tRNA synthetase, Candida albicans N-Myristoyltransferase, Human COX-2 enzyme, and Human Peroxiredoxin 5 revealed good binding profiles with the target proteins. The interaction's stability was further assessed using a conventional atomistic 100 ns dynamic simulation study. Hence, our results recommended the rationalized targets 4a, 4b and 4d, to be promising lead candidates for the discovery of novel dual anti-inflammatory and anti-infection agents.     

Synthesis and biological evaluation of novel 1,2,4-triazole containing 1,2,3-thiadiazole derivatives

A series of novel 1,2,4-triazoles containing 1,2,3-thiadiazole derivatives were designed and synthesized. Their structures were confirmed by melting points, IR, 1H NMR, and elemental analysis and ESI-MS or HRMS. Preliminary bioassays indicated that these compounds exhibited very good insecticidal activity against Aphis laburni at 100 μg/mL, with mortality no less than 95%. Compounds 6a, 6c, 6f, 61 showed higher curative activity against TMV and compound 6h showed a higher induction effects against TMV in vivo at 100 μg/mL. Collectively, our data demonstrate a new strategy for control of insects and viruses.     

Synthesis,biological evaluation,quantitative-SAR and docking studies of novel chalcone derivatives as antibacterial and antioxidant agents

In the present study, a series of chalcone derivatives including 17 new compounds were synthesised; their antibacterial activities against eleven bacteria, and their free radical-scavenging activities using DPPH were evaluated. All compounds showed significant antibacterial activities against both Gram-positive and Gram-negative bacteria. In particular, compound IIIf strongly inhibited Staphylococcus aureus (JMC 2151) and Enterococcus faecalis (CARS 2011-012) with MIC values of 6.25 µg mL^?1 and 12.5 µg mL^?1, respectively, which are comparable to that of the standard antibiotic, nalidixic acid. Compound IIIg also inhibited S. aureus with a MIC value similar to that of nalidixic acid (6.25 µg mL^?1). Furthermore, like nalidixic acid (MIC value of 25 µg mL^?1), compounds IIIa, IIIc and IIId inhibited Listeria monocytogenes (ATCC 43256) with MIC values of 25 µg mL^?1, 12.5 µg mL^?1 and 25 µg mL^?1, respectively. Quantitative structure-activity relationship (Q-SAR) studies using physicochemical calculations indicated that the antibacterial activities of chalcone derivatives correlated well with predicted physicochemical parameters (logP and PSA). Docking simulation by positioning the most active compound IIIf in the active site of the penicillin-binding protein (PBP-1b) of S. aureus was performed to explore the feasible binding mode. Furthermore, most of the compounds synthesised exhibited significant DPPH radical-scavenging activity, although compounds IIc and IIIc exhibited the greatest antioxidant activity with IC₅₀ values of 1.68 µM and 1.44 µM, respectively, comparable to that of the standard antioxidant, ascorbic acid (1.03 µM).     

Novel imidazole derivatives as antifungal agents: Synthesis,biological evaluation,ADME prediction and molecular docking studies

Abstract

A series of 2-(substituteddithiocarbamoyl)-N-[4-((1H-imidazol-1-yl)methyl)phenyl]acetamide derivatives was designed and synthesized to combat the increasing incidence of drug-resistant fungal infections. All synthesized compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, and HRMS spectra and elemental analyses. Antifungal activity tests were performed against four different fungal strains. Molecular docking studies were performed to investigate the mode of action towards the fungal lanosterol 14α-demethylase, a cytochrome P450-dependent enzyme. ADME studies were carried out and a connection between activities and physicochemical properties of the target compounds was determined. Most of the final compounds exhibited significant activity against Candida albicans and Candida krusei with MIC₅₀ value 12.5?μg/mL. The results of in vitro anti-Candida activity, a docking study and ADME prediction revealed that the newly synthesized compounds have potential anti-Candida activity and evidenced the most active derivative, 5b (2-Pyrrolidinthiocarbonylthio-N-[4-((1H-imidazol-1-yl)methyl)phenyl]acetamide), which can be further optimized as a lead compound.     

Synthesis,biological evaluation and molecular docking study of dihydropyrimidine derivatives as potential anticancer agents

A series of dihydropyrimidine analogues were prepared via one-pot Biginelli three-component condensation reaction and characterized by NMR, FT-IR, MS spectra, and element analysis. Subsequently, they were screened for in vitro anticancer effect. These analogues revealed good cytotoxic activity against three human cancer cell lines including MCF-7, HepG-2, and A549. Among these analogues, compounds 4d and 4h were the most potent against three cell lines. Cell viability assays indicated 4a and 4c had lower cytotoxicity. In vitro cytotoxicity study on all synthesized compounds demonstrated that introduction of electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine contributed to the antiproliferative potency. Moreover, in silico molecular docking results stipulated a sign of good correlation between experimental activity and calculated binding affinity. It proved 4d and 4h as the strongest compounds. Binding modes of analogues proposed the involvement of hydrophobic interactions and hydrogen bonds with Eg5 active site. Structure activity relationship studies indicated that incorporating electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine are important for this biological activity.     

Synthesis,biological evaluation,and molecular docking studies of novel pyrazole,pyrazoline-clubbed pyridine as potential antimicrobial agents

We have prepared 15 hybrid pyrazole, pyrazoline-clubbed pyridine–containing compounds (5a-o) and tested for their antibacterial and antifungal activities for the development of potential antimicrobial agents. The structures of this novel series were characterized by various spectral techniques like IR, ¹H NMR, ¹³C NMR, LC–MS, and elemental analysis. The synthesized compounds 5d, 5e, 5i, 5k, 5m, and 5o exhibited significant antimicrobial activity in the comparison of standard drugs. Molecular docking studies that have been carried out to emphasize the binding orientations of these molecules were in good compliance with crystal structure interactions. The predicted drug-likeness (ADME) properties were found to be in the acceptable range.     

Synthesis of new 1,2,3-triazole linked benzimidazolidinone: Single crystal X-ray structure,biological activities evaluation and molecular docking studies

A novel series of 1,2,3-triazole-benzimidazolidinone hybrid derivatives were designed and synthesized via click reaction, between various aryl azide and a terminal alkyne bearing a benzimidazolidinone moiety. All newly synthesized compounds, were efficiently characterized using ¹H NMR, ¹³C NMR and HRMS. Furthermore, the structure of one precursor 5b was supported by single crystal X-ray diffraction. All synthesized derivatives have been evaluated for their antimicrobial and anti-inflammatory activities. Biological activity tests exhibited that the target structures demonstrate that compounds 5a, 5b and 5f have a high antibacterial activity especially derivative 5b. Besides, the in vitro antifungal results revealed that the strongest inhibition recorded to compound 5b in comparison to other products against A. brasiliensis, A. fumigatus and C. albicans. Biological activity evaluation indicated that the synthesized compounds possess moderate anti-inflammatory effects. The most effective compound in terms of efficacy and potency was 5a. Molecular docking simulation was used to investigate the most active compounds' probable binding mechanisms in order to provide a plausible explanation for their biological activity.     

Design,synthesis, and biological evaluation of 1,2,4-triazole derivatives as potent antitubercular agents

Inhibition of mycobacterial membrane protein large 3(MmpL3) thereby affecting the mycolic acid biosynthetic pathway has been proven to be an effective strategy for developing antitubercular drugs. Based on the X-ray crystal structure of MmpL3 inhibitor complexes, a series of novel 1,2,4-triazole derivatives were designed, synthesized and evaluated antitubercular activity against Mtb strain H37Rv. Comprehensive structure–activity relationship exploration resulted in the identification of compound...     

Synthesis,biological evaluation,and molecular docking studies of diacylhydrazine derivatives possessing 1,4-benzodioxan moiety as potential anticancer agents

Russian Journal of General Chemistry - A series of diacylhydrazine derivatives containing 1,4-benzodioxan 1-17 has been designed, synthesized and evaluated for antitumor activity. Most of the...     

Synthesis,biological evaluation and computational studies of fused acridine containing 1,2,4-triazole derivatives as anticancer agents

A novel series of fused acridine containing 1,2,4-triazole derivatives (13a-j) have been synthesized and their structures were confirmed by ¹HNMR, 13CNMR and mass spectral data. Further, all these derivatives were tested for their anticancer activity against four human cancer cell lines A549 (Lung), MCF7 (Breast), A375 (Melanoma) and HT-29 (Colon). The IC₅₀ values range of target compounds shown 0.11 ± 0.02 to 13.8 ± 0.99 µM as compared with standard drug range 0.11 ± 0.02 to 0.93 ± 0.056 µM. Among them, compounds 13d, 13f, 13g, 13h, 13i, and 13j were exhibited more potent activity. Docking simulation was performed as a trial to study the mechanisms and binding modes of these compounds towards the DNA target. The results showed these compounds have intercalated placement in the active sites and stable interactions similar to the co-crystallized reference ligand. Further, these compounds (13a-j) were investigated for Drug-likeness, ADME properties and Toxicity risk assessment.     

Synthesis,molecular modeling,and pharmacological evaluation of new 2-substituted benzoxazole derivatives as potent anti-inflammatory agents

Structural Chemistry - In the present work, 2-substituted benzoxazole derivatives were synthesized from 2-(benzo[d]oxazol-2-yl) aniline. All the synthesized compounds were purified and...     

Synthesis,cytotoxicity, apoptosis and molecular docking studies of novel phenylbutyrate derivatives as potential anticancer agents

Phenylbutyrate (PB), a small aromatic fatty acid, has been known as an interesting compound with the ability of anti-proliferation and cell growth inhibition in cancer cells. In the present study, a series of PB derivatives were synthesized by Passerini multicomponent reaction and their cytotoxic activities against various human cancer cell lines including A549 (non-small cell lung cancer), MDA-MB-231 (breast cancer), and SW1116 (colon cancer) were evaluated. The results revealed that B9, displayed significantly higher in vitro cytotoxicity with IC₅₀ of 6.65, 8.44 and 24.71 μM, against A549, MDA-MB-231 and, SW1116, respectively, in comparison to PB. The effects of these compounds on the proliferation of MCF-10A as non-tumoral breast cell line, showed good selectivity of the compounds between tumorigenic and non-tumorigenic cell lines. Moreover, B9 has indicated apoptosis-inducing activities to MDA-MB-231 cancer cell line in a dose-dependent manner. The molecular docking studies of the synthesized compounds on pyruvate dehydrogenase kinase 2 (PDK2; PDB ID: 2BU8) and histone deacetylase complex (HDAC; PDB ID: 1C3R), as the main targets of PB were applied to predict the binding sites and binding orientation of the compounds to these targets.     

Synthesis and biological evaluation of andrographolide derivatives as potent anti-HIV agents

A series of Andro derivatives were described and evaluated for their anti-HIV activity in vitro.Compound 10 and 16b,of which TI were>10,had some anti-HTV-l activity in vitro.Therein,compound 10 which was the best potent compound,could serve as a new lead for further development of anti-AIDS agents.     

Synthesis of isoniazid-1,2,3-triazole conjugates: Antitubercular,antimicrobial evaluation and molecular docking study

In the present study, a series of new isoniazid-1,2,3-triazole conjugates ( 5a-k ) was synthesized via click chemistry approach. The newly synthesized compounds were assessed for their in vitro antitubercular and antimicrobial activities. The compound 5g has displayed potent antitubercular activity against Mycobacterium tuberculosis H37Rv (Mtb) with MIC value 1.56 μg/mL. The active compounds were screened for their cytotoxicity profile by MTT assay against RAW 264.7 cell line. The four compounds have shown good in vitro antimicrobial activities against both antibacterial and antifungal pathogens. A molecular docking study was accomplished to identify the probable mode of action of synthesized derivatives. These compounds have shown excellent binding affinity toward Enoyl-acp reductase (INHA) and DNA gyrase.     

Synthesis,docking and ADME prediction of novel 1,2,3-triazole-tethered coumarin derivatives as potential neuroprotective agents

Research on Chemical Intermediates - In an attempt to find potential neuroprotective agents, a series of novel 3-(1-((1-(substituted phenyl)-1H-1,2,3-triazol-4-yl) methoxyimino)...     

Synthesis,biological evaluation,and docking study of a series of 1,4-disubstituted 1,2,3-triazole derivatives with an indole-triazole-peptide conjugate

A series of new compounds containing an indole-triazole - peptide conjugate were designed as potential agents possessing the dual anti-bacterial and anticancer activities. Accordingly, 20 compounds were prepared via a multi-step synthesis involving the copper-catalyzed azide-alkyne cycloaddition (CuAAC) as a key step in moderate to high yield. All the synthesized compounds were purified by chromatographic techniques and characterized by IR, ¹H and ¹³C NMR and mass spectral data. The synthesized derivatives were screened for their antimicrobial activities against one gram-positive (Staphylococcus aureus) and three gram-negative (Escherichia coli, Klebsiella pneumonia, and Proteus vulgaris) bacteria using an agar-well diffusion method. Most of the compounds showed moderate to reasonable antibacterial activities especially the compound 9e that showed good activities against all the strains. The potential of DNA gyrase inhibitory activity of this compound was assessed by using molecular docking studies in silico carried out using Autodock Vina software. The low ΔG_bind value (−9.4 Kcal/mol) of compound 9e suggested its good interactions with the target protein in silico. The cytotoxic activities of some of the compounds synthesized were evaluated via a MTT assay using the human lung cancer cell line A549. Several compounds showed promising activities among which compound 9b , 9k, and 9e showed low IC₅₀ values.     

Synthesis,biological evaluation and molecular docking studies of novel 2-(2-cyanophenyl)-N-phenylacetamide derivatives

A series of novel 2-(2-cyanophenyl)-N-phenylacetamide derivatives 3(a-u) were designed and synthesized via selective amidation of methyl-2-(2-cyanophenyl)acetates over amidine formation by using AlMe₃ as catalyst in good yields. All the newly synthesized derivatives were well characterized by ¹H NMR, ¹³C NMR, FTIR and HRMS spectral techniques. All the synthesized title compounds were evaluated for their in vitro anticancer activity against three cancer cell lines. Among all compounds, 3i (IC₅₀?=?1.20 μM, IC₅₀?=?1.10 μM), 3j (IC₅₀?=?0.11 μM, IC₅₀?=?0.18 μM), 3o (IC₅₀?=?0.98 μM, IC₅₀?=?2.76 μM) showed excellent inhibitory activity than the standard Etoposide (IC₅₀?=?2.11 μM, IC₅₀?=?3.08 μM) against MCF-7 and A-549 cell lines, respectively. Docking analysis of all the compounds with the human topoisomerase II revealed that the compound 3j fitted well in the active site pocket, showing the best docking score of 158.072 kcal/mol.