Structure-based inhibition of acetylcholinesterase and butyrylcholinesterase with 2-Aryl-6-carboxamide benzoxazole derivatives: synthesis, enzymatic assay, and in silico studies.

An important research topic is the discovery of multifunctional compounds targeting different disease-causing components. This research aimed to design and synthesize a series of 2-aryl-6-carboxamide benzoxazole derivatives that inhibit cholinesterases on both the peripheral anionic and catalytic anionic sides. Compounds (7-48) were prepared from 4-amino-3-hydroxybenzoic acid in three steps. The Ellman test, molecular docking with Maestro, and molecular dynamics simulation studies with Desmond were done (Schrodinger, 12.8.117). Compound 36, the most potent compound among the 42 new compounds synthesized, had an inhibitory concentration of IC50 12.62 nM for AChE and IC50 25.45 nM for BChE (whereas donepezil was 69.3 nM and 63.0 nM, respectively). Additionally, compound 36 had docking values ​​of - 7.29 kcal/mol for AChE and - 6.71 kcal/mol for BChE (whereas donepezil was - 6.49 kcal/mol and - 5.057 kcal/mol, respectively). Furthermore, molecular dynamics simulations revealed that compound 36 is stable in the active gorges of both AChE (average RMSD: 1.98 Å) and BChE (average RMSD: 2.2 Å) (donepezil had average RMSD: 1.65 Å and 2.7 Å, respectively). The results show that compound 36 is a potent, selective, mixed-type dual inhibitor of both acetylcholinesterase and butyrylcholinesterase. It does this by binding to both the catalytically active and peripheral anionic sites of cholinesterases at the same time. These findings show that target compounds may be useful for establishing the structural basis for new anti-Alzheimer agents.

Design, synthesis, and computational studies of benzimidazole derivatives as new antitubercular agents.

The increase in the drug-resistant strains of Mycobacterium tuberculosis has led researchers to new drug targets. The development of new compounds that have effective inhibitory properties with the selective vital structure of Mycobacterium tuberculosis is required in new scientific approaches. The most important of these approaches is the development of inhibitor molecules for Mycobacterium cell wall targets. In this study, first of all, the antitubercular activity of 23 benzimidazole derivatives was experimentally determined. And then molecular docking studies were carried out with 4 different targets: Arabinosyltransferase C (EmbC), Filamentous Temperature Sensitive Mutant Z (FtsZ), Protein Tyrosine Phosphatase B (PtpB), and Decaprenylphosphoryl-ß-D-ribose-2'-oxidase (DprE1). It has been determined that benzimidazole derivatives show activity through the DprE1 enzyme. It is known that DprE1, which has an important role in the synthesis of the cell envelope from Arabinogalactan, is also effective in the formation of drug resistance. Due to this feature, the DprE1 enzyme has become an important target for drug development studies. Also, it was chosen as a target for this study. This study aims to identify molecules that inhibit DprE1 for the development of more potent and selective antitubercular drugs. For this purpose, molecular docking studies by AutoDock Vina, and CDOCKER and molecular dynamics (MD) simulations and in silico ADME/Tox analysis were implemented for 23 molecules. The molecules exhibited binding affinity values of less than -8.0 kcal/mol. After determining the compound's anti-TB activities by a screening test, the best-docked results were detected using compounds 20, 21, and 30. It was found that 21, was the best molecule with its binding affinity value, which was supported by MD simulations and in silico ADME modeling results.Communicated by Ramaswamy H. Sarma.

Exploring enzyme inhibition profiles of novel halogenated chalcone derivatives on some metabolic enzymes: Synthesis, characterization and molecular modeling studies.

Enzyme inhibition is a very active area of research in drug design and development. Chalcone derivatives have a broad enzyme inhibitory activity and function as potential molecules in the development of new drugs. In this study, the synthesized novel halogenated chalcones with bromobenzyl and methoxyphenyl moieties were evaluated toward the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes and human erythrocyte carbonic anhydrase I (hCA I), and II (hCA II) isoenzymes. They showed highly potent inhibition ability toward AChE with Ki values of 1.83 ± 0.21-11.19 ± 0.96 nM and BChE with Ki values of 3.35 ± 0.91-26.70 ± 4.26 nM; hCA I with Ki values of 29.41 ± 3.14-57.63 ± 4.95 nM, and hCA II with Ki values of 24.00 ± 5.39-54.74 ± 1.65 nM. Among the tested enzyme inhibitions, compounds 14 and 13 were the most active compounds against AChE and BChE. Docking studies were performed to the most active compounds against AChE, BChE, hCA I and hCA II to propose a binding mode in the active site and molecular dynamics simulations were studied to check the molecular interactions and the stability of the ligands in the active site. The results may contribute to the development of new drugs particularly to treat some global disorders including Alzheimer's disease (AD), glaucoma, and diabetes.

Design, synthesis and in vitro antiproliferation activity of some 2-aryl and -heteroaryl benzoxazole derivatives.

Background: Phortress produces reactive electrophilic metabolites that form DNA adducts only in sensitive tumor cells. The authors converted the 2-phenylbenzothiazole nucleus in phortress to 2-aryl and -heteroaryl benzoxazole derivatives (11 new and 14 resynthesized). All synthesized compounds were studied for antitumor activity in various cancer cells. Materials & methods: Cytotoxicity, cell morphology, flow cytometry and cell-cycle analyses of compounds were performed and more active derivatives were tested in the MCF-7 cell line. Conclusion: Methyl 2-(thiophen-2-yl)benzo[d]oxazole-6-carboxylate (BK89) has a higher effect than fluorouracil to induce apoptotic cell death (apoptosis value of 49.44%). Cell-cycle analysis shows that the compounds BK89 and methyl 2-(furan-2-yl)benzo[d]oxazole-6-carboxylate (BK82) can be used as potential cell-cycle blockers by arresting MCF-7 cells in G0/G1 phase at rates of 63% and 85%, respectively.

There is an urgent need to develop potent and selective anticancer agents. In this study, the design and applications of compounds sensitive to specific cancer cells and targeting cancer cells were investigated. The results show that the synthesized compounds can be antiproliferative drug candidates for breast cancer. These compounds may shed light on cancer treatment and cancer research.

Design, synthesis and antiproliferative activity evaluation of fluorine-containing chalcone derivatives.

A series of new chalcones containing fluoro atom at B ring have been designed, synthesized, and evaluated to be antiproliferative activity against a panel of human tumor cell lines. Some of the analogs (8, 9, 12, 45, 46 and 48) displayed powerful antiproliferative effects to certain human tumor cells, but all of them were devoid of any cytotoxicity towards the normal HEK 293. Acridine orange staining data supported that the cytotoxic and antiproliferative effects of the synthesized analogs on tumor cells are mediated through apoptosis. The compounds 12 and 46 manifested concentration-dependent antiproliferative activity in human hepatocellular carcinoma cell lines using an xCELLigence assay. The structures and antiproliferative activity relationship were further supported by in silico molecular docking study of the compounds against tubulin protein which suggests our compounds interference to cell division. Communicated by Ramaswamy H. Sarma.

New chalcone derivatives as effective against SARS-CoV-2 agent.

AIMS: Flavonoids and related compounds, such as quercetin-based antiviral drug Gene-Eden-VIR/Novirin, inhibit the protease of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The alkylated chalcones isolated from Angelica keiskei inhibit SARS-CoV proteases. In this study, we aimed to compare the anti-SARS CoV-2 activities of both newly synthesized chalcone derivatives and these two drugs. METHODS: Determination of the potent antiviral activity of newly synthesized chalcone derivatives against SARS-CoV-2 by calculating the RT-PCR cycling threshold (Ct ) values. RESULTS: Antiviral activities of the compounds varied because of being dose dependent. Compound 6, 7, 9, and 16 were highly effective against SARS-CoV-2 at the concentration of 1.60 µg/mL. Structure-based virtual screening was carried out against the most important druggable SARS-CoV-2 targets, viral RNA-dependent RNA polymerase, to identify putative inhibitors that could facilitate the development of potential anti-coronavirus disease-2019 drug candidates. CONCLUSIONS: Computational analyses identified eight compounds inhibiting each target, with binding affinity scores ranging from -4.370 to -2.748 kcal/mol along with their toxicological, ADME, and drug-like properties.

Synthesis and biological evaluation of 3,5-diaryl-pyrazole derivatives as potential antiprostate cancer agents.

Prostate cancer is the most frequently diagnosed tumor in men and the second leading cause of cancer-associated mortality in most developed countries. 3,5-Diaryl substituted pyrazole derivatives (20-28) were prepared starting from related chalcones and biologically evaluated for in vitro growth inhibition activity against PC3 and DU145 human prostate cancer cell lines. Compounds 23, 26, and 28 were found to be more potent as compared to the other halogen-substituted derivatives. Especially, the 2-bromo-substituted pyrazole derivative (26) was found to be more potent against PC3 and DU145 cells. Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 2 (VEGFR2) are known to be expressed in DU145 and PC3 cancer cells. The binding mode of the most selective compound 26 toward EGFR and VEGFR2 was investigated by employing docking simulations based on GLIDE standard precision (-5.912 and -6.949 kcal/mol, respectively).

Design, synthesis and biological evaluation of novel bischalcone derivatives as potential anticancer agents.

Building on our previous work that discovered chalcone as a promising pharmacophore for anticancer activity, we have various other chalcone derivatives and have synthesized a series of novel bischalcone to explore their anticancer activity. Among all tested compounds, compounds 6a, 6b, and 6c showed the highest antiproliferative activity against A-549 cancer cell lines with the average IC50 values of 4.18, 4.52, and 5.05 µM, respectively. Moreover, compound 6c showed high antiproliferative activity against the Caco-2 cell line; thus, it was 2- and 4-fold more active than the reference compounds, i.e., methotrexate and capecitabine. Compound 6a also induced cell-cycle arrest in the S phase, whereas compounds 6b and 6c were observed to stop at the G0/G1 phase. Thereafter, we evaluated that compound 6c also had the highest apoptosis/necrosis ratio than other compounds and the standard compound. The anticancer property of the 6c was also supported by molecular docking studies carried out on the EGFR and HER2 receptors. Overall, we expect that these compounds can be further developed for the potential treatment of lung cancer.

Synthesis of novel tris-chalcones and determination of their inhibition profiles against some metabolic enzymes.

In this study, we report the synthesis of novel tris-chalcones and testing of human carbonic anhydrase I, and II isoenzymes (hCA I, and hCA II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase (α-Gly) inhibitors for the development of novel chalcone structures towards for treatment of some diseases. The compounds demonstrated Ki values between 13.6 ± 1.1 and 50.0 ± 17.1 nM on hCA I, 9.9 ± 0.8 and 39.5 ± 15.1 nM on hCA II, 3.1 ± 0.2 and 20.1 ± 1.9 nM on AChE, 4.9 ± 0.4 and 14.7 ± 5.2 nM on BChE and 3.9 ± 0.2 and 22.4 ± 10.7 nM on α-Gly enzymes. The results revealed that novel tris-chalcones can have promising drug potential for glaucoma, leukaemia, epilepsy; Alzheimer's disease that was associated with the high enzymatic activity of hCA I, hCA II, AChE, and BChE enzymes.

An efficient synthesis of novel di-heterocyclic benzazole derivatives and evaluation of their antiproliferative activities.

A series of unsymmetrical nine di-heterocyclic compounds of benzazole derivatives were synthesized at one step via cyclization reaction. The compounds evaluated for in vitro cytotoxic activity against A549, A498, HeLa, and HepG2 cancer cell lines. The biological evaluation results show that 23, 26 and 29 exhibit better activity against HepG2 and HeLa cancer cell lines. Compound 23 also showed good activity against A549, and A498 cancer cell lines. The analogs were further performed molecular docking studies against human cytochrome P450 2C8 monooxygenase enzyme, calculated some theoretical quantum parameters, ADMET descriptor and molecular electrostatic potential analysis. The strategy applied in this research work may act as a perspective for the rational design of potential anticancer drugs. Communicated by Ramaswamy H. Sarma.

Head-to-head bisbenzazole derivatives as antiproliferative agents: design, synthesis, in vitro activity, and SAR analysis.

In the present work, a series of bisbenzazole derivatives were designed and synthesized as antiproliferative agents. The antiproliferative activity of these compounds was investigated using MTT assay. Bisbenzazole derivatives showed significant antiproliferative activity against all the four tested cancer cell lines. Among the various bisbenzazole derivatives, bisbenzoxazole derivatives exhibited the most promising anticancer activity followed by bisbenzimidazole and bisbenzothiazole derivatives. All the derivatives were found to be less toxic as compared to methotrexate (positive control) in normal human cells, indicating selective and efficient antiproliferative activity of these bisbenzazole derivatives. The structure-activity relationships of heteroaromatic systems and linkers present in bisbenzazole derivatives were analyzed in detail. In silico ADMET prediction revealed that bisbenzazole is a drug-like small molecule with a favorable safety profile. Compound 31 is a potential antiproliferative hit compound that exhibits unique cytotoxic activity distinct from methotrexate. Twenty-one bisbenzoxazole derivatives have been designed synthesized and evaluated to be an antiproliferative activity against four human tumor cell lines.

Design, synthesis and biological evaluation of 3,5-diaryl isoxazole derivatives as potential anticancer agents.

The present study was carried out in the attempt to synthesize a new class of potential anticancer agents comprising eleven compounds (24-34) sharing the 3,5-diarylisoxazole as a core. The chemical structure of the new synthesized compounds was established by IR, 1H NMR, 13C NMR and elemental analysis. Their biological potential towards prostate cancer was evaluated by using cancer PC3 cells and non-tumorigenic PNT1a cells. Interestingly, compound 26 distinguished from others with a quite high selectivity value that is comparable to 5-FU. The binding mode of 26 towards Ribosomal protein S6 kinase beta-1 (S6K1) was investigated at a molecular level of detail by employing docking simulations based on GLIDE standard precision as well as MM-GBSA calculations.

Synthesis, biological evaluation and molecular docking studies of bis-chalcone derivatives as xanthine oxidase inhibitors and anticancer agents.

In this study, a series of B-ring fluoro substituted bis-chalcone derivatives were synthesized by Claisen-Schmidt condensation reactions and evaluated for their ability to inhibit xanthine oxidase (XO) and growth inhibitory activity against MCF-7 and Caco-2 human cancer cell lines, in vitro. According to the results obtained, the bis-chalcone with fluoro group at the 2 (4b) or 2,5-position (4g) of B-ring were found to be potent inhibitors of the enzyme with IC50 values in the low micromolar range. The effects of these compounds were about 7 fold higher than allopurinol. The binding modes of the bis-chalcone derivatives in the active site of xanthine oxidase were explained using molecular docking calculations. Also, compound 4g and 4h showed in vitro growth inhibitory activity against a panel of two human cancer cell lines 1.9 and 6.8 µM of IC50 values, respectively.

Synthesis and biological evaluation of novel tris-chalcones as potent carbonic anhydrase, acetylcholinesterase, butyrylcholinesterase and α-glycosidase inhibitors.

A novel class of fluoro-substituted tris-chalcones derivatives (5a-5i) was synthesized from phloroglucinol and corresponding benzaldehydes. A three step synthesis method was followed for the production of these tris-chalcone compounds. The structures of the newly synthesized compounds (5a-5i) were confirmed on the basis of IR, 1H NMR, 13C NMR, and elemental analysis.The compounds' inhibitory activities were tested against human carbonic anhydrase I and II isoenzymes (hCA I and hCA II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase (α-Gly). These chalcone derivatives had Ki values in the range of 19.58-78.73 nM for hCA I, 12.23-41.70 nM for hCA II, 1.09-6.84 nM for AChE, 8.30-32.30 nM for BChE and 0.93 ±â€¯0.20-18.53 ±â€¯5.06 nM against α-glycosidase. These results strongly support the promising nature of the tris-chalcone scaffold as selective carbonic anhydrase, acetylcholinesterase, butyrylcholinesterase, and α-glycosidase inhibitor. Overall, due to these derivatives' inhibitory potential on the tested enzymes, they are promising drug candidates for the treatment of diseases like glaucoma, leukemia, epilepsy; Alzheimer's disease; type-2 diabetes mellitus that are associated with high enzymatic activity of carbonic anhydrase, acetylcholine esterase, butyrylcholinesterase, and α-glycosidase.

Synthesis and biological evaluation of phloroglucinol derivatives possessing α-glycosidase, acetylcholinesterase, butyrylcholinesterase, carbonic anhydrase inhibitory activity.

A series of novel phloroglucinol derivatives were designed, synthesized, characterized spectroscopically and tested for their inhibitory activity against selected metabolic enzymes, including α-glycosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase I and II (hCA I and II). These compounds displayed nanomolar inhibition levels and showed Ki values of 1.14-3.92 nM against AChE, 0.24-1.64 nM against BChE, 6.73-51.10 nM against α-glycosidase, 1.80-5.10 nM against hCA I, and 1.14-5.45 nM against hCA II.

Syntheses and evaluation of multicaulin and miltirone-like compounds as antituberculosis agents.

Four multicaulin and miltirone-like phenanthrene derivatives were synthesised and evaluated as antituberculosis agents. The crucial step of the synthesis was Pschorr coupling of 4-(3-isopropyl-4-methoxyphenyl)-2-(2-aminophenyl)ethane (13) to give 2-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9) and 4-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9a). Compound 9 was converted to multicaulin and miltirone-like phenanthrene derivatives by further reactions. The best antituberculosis activity was exhibited by 2-isopropylphenanthrene-3-ol (11).

Sensing by Smell: Nanoparticle-Enzyme Sensors for Rapid and Sensitive Detection of Bacteria with Olfactory Output.

We present here a highly efficient sensor for bacteria that provides an olfactory output, allowing detection without the use of instrumentation and with a modality that does not require visual identification. The sensor platform uses nanoparticles to reversibly complex and inhibits lipase. These complexes are disrupted in the presence of bacteria, restoring enzyme activity and generating scent from odorless pro-fragrance substrate molecules. This system provides rapid (15 min) sensing and very high sensitivity (102 cfu/mL) detection of bacteria using the human sense of smell as an output.

Design of potent fluoro-substituted chalcones as antimicrobial agents.

Owing to ever-increasing bacterial and fungal drug resistance, we attempted to develop novel antitubercular and antimicrobial agents. For this purpose, we developed some new fluorine-substituted chalcone analogs (3, 4, 9-15, and 20-23) using a structure-activity relationship approach. Target compounds were evaluated for their antitubercular efficacy against Mycobacterium tuberculosis H37Rv and antimicrobial activity against five common pathogenic bacterial and three common fungal strains. Three derivatives (3, 9, and 10) displayed significant antitubercular activity with IC50 values of ≤16,760. Compounds derived from trimethoxy substituent scaffolds with monofluoro substitution on the B ring of the chalcone structure exhibited superior inhibition activity compared to corresponding hydroxy analogs. In terms of antimicrobial activity, most compounds (3, 9, 12-14, and 23) exhibited moderate to potent activity against the bacteria, and the antifungal activities of compounds 3, 13, 15, 20, and 22 were comparable to those of reference drugs ampicillin and fluconazole.

Synthesis and anti-proliferative activity of fluoro-substituted chalcones.

A series of novel fluoro-substituted chalcone derivatives have been synthesized. All synthesized compounds were characterized by (1)H nuclear magnetic resonance (NMR), (13)C NMR, and elemental analysis. Their anti-proliferative activities were evaluated against five cancer cells lines, namely, A549, A498, HeLa, A375, and HepG2 using the MTT method. Most of the compounds showed moderate to high activity with IC50 values in the range of 0.029-0.729µM. Of all the synthesized compounds, 10 and 19 exhibited the most potent anti-proliferative activities against cancer cells, and 10 was identified as the most promising compound.

Synthesis of two phloroglucinol derivatives with cinnamyl moieties as inhibitors of the carbonic anhydrase isozymes I and II: an in vitro study.

Two cinnamyl-substituted phloroglucinols, 4-p-methoxycinnamyl phloroglucinol (9) and 4,6-bis-p-methoxycinnamyl phloroglucinol (10) were synthesized. Two carbonic anhydrases, human carbonic anhydrase I and II (hCA I and II), were purified. Kinetic interactions between these isozymes with 9 and 10 were investigated. These new compounds exhibited inhibitory effects on the hCA I and II enzymes' activity in vitro. The combination of the inhibitory effects of both phloroglucinol and p-coumaric acid groups in a single compound was explored. However, relative to the inhibitory effects of the two groups separately, compounds 9 and 10 demonstrated comparable inhibitory effects. More effective inhibitors of CAs could be created by testing these compounds on other CA isozymes.