Synthesis, molecular docking study and biological evaluation of new pyrrole scaffolds as potential antitubercular agents for dual targeting of enoyl ACP reductase and dihydrofolate reductase.

In this study, new series of N'-(2-(substitutedphenoxy)acetyl)-4-(1H-pyrrol-1-yl)benzohydrazides (3a-j) 4-(2,5-dimethyl-1H-pyrrol-1-yl)-N'-(2-(substitutedphenoxy)acetyl)benzohydrazides (5a-j) were synthesized, characterized and assessed as inhibitors of enoyl ACP reductase and DHFR. Most of the compounds exhibited dual inhibition against the enzymes enoyl ACP reductase and DHFR. Several synthesized substances also demonstrated significant antibacterial and antitubercular properties. A molecular docking analysis was conducted in order to determine the potential mechanism of action of the synthesized compounds. The results indicated that there were binding interactions seen with the active sites of dihydrofolate reductase and enoyl ACP reductase. Additionally, important structural details were identified that play a critical role in sustaining the dual inhibitory activity. These findings were useful for the development of future dual inhibitors. Therefore, this study provided strong evidence that several synthesized molecules could exert their antitubercular properties at the cellular level through multi-target inhibition. By shedding light on the mechanisms through which these compounds exert their inhibitory effects, this research opens up promising avenues for the future development of dual inhibitors with enhanced antibacterial and antitubercular properties. The study's findings underscore the importance of multi-target approaches in drug design, providing a strong foundation for the design and optimization of novel compounds that can effectively target bacterial infections at the cellular level.

New thiophene-1,3,4-oxadiazole-thiazolidine-2,4-dione hybrids: Synthesis, MCF-7 inhibition and binding studies.

Two synthetic methods were proposed for the preparation of a new series of thiophene-1,3,4-oxadiazole-thiazolidine-2,4-dione hybrids (TOT-1 to 15) and their structures were elucidated based on spectral data. Studies on cytotoxicity, ROS, cellular uptake and interactions of TOT-14 with calf thymus DNA were carried out. Anticancer activity of compounds, TOT-1 to 15 on breast cancer (MCF-7) cell lines was investigated. The IC50 values for the standard, epirubicin hydrochloride and TOT-12, 13, 14 and 15 were found to be 6.78, 5.52, 6.53, 4.83 and 5.57 µg/mL, respectively. Notably, TOT-14 exhibited a remarkable antiproliferative activity with a strikingly selective inhibitory effect compared to standard. This specific selectivity could be attributed to the synergistic effect of increased cellular uptake and generation of higher ROS in cancer cells after irradiation. The binding constant of 4.25 x 103 M-1 indicated the moderate interaction between TOT-14 and ct-DNA. The docking score of TOT derivativeswas substantially identical to the docking score of epirubicin hydrochloride. The designed molecules complied with the requirements for drug-likeness and ADME.

Synthesis, molecular simulation studies, in vitro biological assessment of 2-substituted benzoxazole derivatives as promising antimicrobial agents.

The 2-substituted benzoxazole derivatives are known to exhibit a wide spectrum of biological potential. Two series of novel benzoxazole derivatives containing 2-phenyl and 2-N-phenyl groups were synthesized, by following the green chemistry approach. All the newly synthesized derivatives were screened against gram-positive bacteria (Streptococcus pyogenes, Staphylococcus aureus), gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and the fungus (Aspergillus clavatus and Candida albicans). Most of these compounds have demonstrated potent antibacterial activities, especially against E. coli at 25 µg/mL, along with moderate antifungal activity. Among these, two compounds, 21 and 18, showed interesting antibacterial profile. Molecular docking studies suggested that the antibacterial activity can be linked to the inhibition of DNA gyrase. Overall, the study proposes that these biologically potent compounds can be considered for developing the next generation antimicrobial agents.

Synthesis, Molecular Docking Study, and Biological Evaluation of New 4-(2,5-Dimethyl-1H-pyrrol-1-yl)-N'-(2-(substituted)acetyl)benzohydrazides as Dual Enoyl ACP Reductase and DHFR Enzyme Inhibitors.

In this study, a new series of 4-(2,5-dimethyl-1H-pyrrol-1-yl)-N'-(2-(substituted)acetyl) benzohydrazides (5a-n) were prepared and new heterocycles underwent thorough characterization and evaluation for antibacterial activity; some of them underwent further testing for in vitro inhibition of enoyl ACP reductase and DHFR enzymes. The majority of the synthesized molecules exhibited appreciable action against DHFR and enoyl ACP reductase enzymes. Some of the synthesized compounds also showed strong antibacterial and antitubercular properties. In order to determine the potential mode of action of the synthesized compounds, a molecular docking investigation was conducted. The results revealed binding interactions with both the dihydrofolate reductase and enoyl ACP reductase active sites. These molecules represent excellent future therapeutic possibilities with potential uses in the biological and medical sciences due to the compounds' pronounced docking properties and biological activity.

Coumarin-4-yl-1,2,3-triazol-4-yl-methyl-thiazolidine-2,4-diones: Synthesis, glucose uptake activity and cytotoxic evaluation.

Thiazolidinedione (TZD) based medications have demonstrated to enhance the insulin sensitivity control, hyperglycemia, and lipid metabolism in patients with type 2 diabetes. Hence, in this study, a new series of novel coumarin-4-yl-1,2,3-triazol-4-yl-methyl-thiazolidine-2,4-diones (TZD1-TZD18) were synthesized via copper (I)-catalyzed azide-alkyne cycloaddition "Click Chemistry". The synthesized compounds were evaluated for their glucose uptake assay and in vitro cytotoxicity against HEK-293 (human embryonic kidney) cells which were compared with the standard drug Pioglitazone. Further, molecular docking analysis of these compounds was carried out to explain the in vitro results with PPARγ (PDB ID: 3CS8) and to better understand the bonding interactions with the target protein. The outcomes of in vitro assessment, molecular docking, and pharmacokinetics of the title compounds were revealed to be highly correlated. Interestingly, the compounds TZD4, TZD10, TZD14 and TZD16 were most efficient in lowering the blood glucose level compared with standard drug.

Synthesis, molecular docking studies, and in vitro antimicrobial evaluation of piperazine and triazolo-pyrazine derivatives.

For this work, two series of new piperazine derivatives (3a-o) and triazolo-pyrazine derivatives (3p-t) were synthesized in a single-step reaction. All twenty adducts were obtained in good to high yields and fully characterized by 1H NMR, 13C NMR, IR, and mass spectrometry techniques. To further confirm the chemical identity of the adducts, a crystal of N-{[(4-chlorophenyl)-3-(trifluoromethyl)]-5,6-dihydro-[1,2,4]triazolo[4,3-a]}pyrazine-7(8H)-carboxamide (3t) was prepared and analyzed using X-ray crystallography. In vitro screening of the antimicrobial activity of all compounds (3a-t) was evaluated against five bacterial and two fungal strains. This study disclosed that N-{[(3-chlorophenyl)]-4-(dibenzo[b,f][1,4]thiazepin-11-yl)}piperazine-1-carboxamide (3o) was the superior antimicrobial with good growth inhibition against A. baumannii. Furthermore, the results from the performed molecular docking studies were promising, since the observed data could be used to develop more potent antimicrobials.

WELPSA: A natural catalyst of alkali and alkaline earth metals for the facile synthesis of tetrahydrobenzo[b]pyrans and pyrano[2,3-d]pyrimidinones as inhibitors of SARS-CoV-2.

Since 2019, the infection of SARS-CoV-2 has been spreading worldwide and caused potentially lethal health problems. In view of this, the present study explores the most commodious and environmentally benign synthetic protocol for the synthesis of tetrahydrobenzo[b]pyran and pyrano[2,3-d]pyrimidinones as SARS-CoV-2 inhibitors via three-component cycloaddition of aromatic aldehyde, malononitrile, and dimedone/barbituric acid in water. Lemon peel from juice factory waste, namely, lemon (Citrus limon), sweet lemon (C. limetta), and Kaffir lime or Citron (C. hystrix), effectually utilized to obtain WELPSA, WESLPSA, and WEKLPSA, respectively, for the synthesis of title compounds. The catalyst was characterized by scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDX). The concentration of sodium, potassium, calcium, and magnesium in the catalyst (WELPSA) was determined using atomic absorption spectrometry (AAS). The current approach manifests numerous notable advantages that include ease of preparation, handling and benignity of the catalyst, low cost, green reaction conditions, facile workup, excellent yields (93%-97%) with extreme purity, and recyclability of the catalyst. Compounds were docked on the crystal structure of SARS-CoV-2 (PDB: 6M3M). The consensus score obtained in the range 2.47-4.63 suggests that docking study was optimistic indicating the summary of all forces of interaction between ligands and the protein.

Synthesis of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives as potential glucosidase inhibitors.

BACKGROUND: A hybrid molecule of different biologically active substances can improve affinity and efficiency compared to a standard drug. Hence based on this fact, we predict that a combination of fluorine, oxadiazole, sulfur, etc., may enhance α-glucosidase inhibition activity compared to a standard drug. METHODS: A series of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives (2a-2i) were synthesized and characterized using spectroscopic techniques such as 1HNMR and LC-MS. In order to evaluate its bioactivity, in vitro α-amylase and α-glycosidase inhibitory activity were performed. In vivo study was carried using a genetic model, Drosophila melanogaster, for assessing the antihyperglycemic effects. RESULTS: The compounds 2a-2i demonstrated α-amylase inhibitory activity in the range of IC50 = 40.00-80.00 µg/ml as compare to standard acarbose (IC50 = 34.71 µg/ml). Compounds 2a-2i demonstrated α-glucosidase inhibitory activity in the range of IC50 = 46.01-81.65 µg/ml as compared to standard acarbose (IC50 = 34.72 µg/ml). Docking studies on a target protein, N-terminal subunit of human Maltase-glucoamylase (PDB:2QMJ) was carried and the compounds were found to dock into the active site of the enzyme (Fig. 1). The predicted binding energies of the compounds were calculated. The in vitro studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. Whereas in vivo study indicates that 2b, 2g, and 2i could lower glucose levels in the Drosophila, but then 17-30% reduced capacity than acarbose and may be overcome by adjusting their dosage. CONCLUSIONS: The in vitro and in vivo studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. This study has recognized that compounds like 2b, 2g, and 2i may be considered potential candidates for further developing a novel class of antidiabetic agents.

Green synthesis of therapeutically active 1,3,4-oxadiazoles as antioxidants, selective COX-2 inhibitors and their in silico studies.

A modest, competent and green synthetic procedure for novel coumarinyl-1,3,4-oxadiazolyl-2-mercaptobenzoxazoles 8i-t has been reported. Analysis of the docked (PDB ID: 5IKR; A-Chain) poses of the compounds illustrated that they adopt identical conformations to the extremely selective COX-2 inhibitor. The biological outcomes as well as computational study suggested that the compounds originated to have elevated resemblance towards COX-2 enzyme than COX-1. The compounds 8i, 8l, 8q, 8r, 8s and 8t emerged as most potent and selective COX-2 inhibitors in contrast with Mefenamic acid. The selectivity index of 8l, 8n and 8r was respectively found to be 33.95, 20.25 and 24.98 which manifested their high selectivity against COX-2. Interestingly, the compounds which were active as COX-2 inhibitors were also active as antioxidant agents.

Microwave assisted regioselective synthesis of quinoline appended triazoles as potent anti-tubercular and antifungal agents via copper (I) catalyzed cycloaddition.

Quinolin-3-yl-methyl-1,2,3-triazolyl-1,2,4-triazol-3(4H)-ones 8j-v were synthesized by click chemistry as an ultimate tactic where [3 + 2] cycloaddition of azides with terminal alkynes has been evolved. Herein, we are inclined to divulge the implication and prevalence of CuSO4·5H2O and THF/water promoted [3 + 2] cycloaddition reactions. The foremost supremacy of this method are transitory reaction times, facile workup, excellent yields (88-92%) with exorbitant purity and regioselective single product formation both under conventional and microwave method. Docking studies illustrated strong binding interactions with enzyme InhA-D148G (PDB ID: 4DQU) by means of high C-score values. The anti-tubercular and antifungal screening of synthesized compounds proclaimed promising activity. The in vitro and in silico studies imply that these triazoles appended quinolines may acquire the ideal structural prerequisites for auxiliary expansion of novel therapeutic agents.

Novel 5-(1-aryl-1H-pyrazol-3-yl)-1H-tetrazoles as glycogen phosphorylase inhibitors: An in vivo antihyperglycemic activity study.

In this study, we report the ring transformation of 3-arylsydnone into 1-aryl-1H-pyrazole-3-carbonitriles via [3 + 2] cycloaddition with acrylonitrile. 1-Aryl-1H-pyrazole-3-carbonitrile underwent [2 + 3] cycloaddition with sodium azide to afford 5-(1-aryl-1H-pyrazol-3-yl)-1H-tetrazoles which were further subjected to N-alkylation with aryl/heteroaryl alkyl halides to afford 1,5- and 2,5-disubstituted tetrazoles. Furthermore, the title compounds were screened for in vivo antihyperglycemic activity using albino Wistar rats of either sex. Compounds 4a, 6b, 7a, 7b, 8b, and 9b showed maximum fall in the blood glucose levels in streptozotocin-induced diabetic rats after 5-7 days of administration. In support of antidiabetic activity, we also performed the experimental in vivo studies, namely, effect of compounds on enzymes (serum glutamic oxaloacetic transaminase, serum glutamic-pyruvic transaminase, creatinine, urea, and total protein), antihyperlipidemic, and histopathology. Moreover, the molecular docking study has been performed for potent molecules among the series with glycogen phosphorylase as target enzyme, and this study corroborated the experimental in vivo results.

New Urea Derivatives as Potential Antimicrobial Agents: Synthesis, Biological Evaluation, and Molecular Docking Studies.

A series of new urea derivatives, containing aryl moieties as potential antimicrobial agents, were designed, synthesized, and characterized by 1H NMR, 13C NMR, FT-IR, and LCMS spectral techniques. All newly synthesized compounds were screened in vitro against five bacterial strains (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus) and two fungal strains (Candida albicans and Cryptococcus neoformans). Variable levels of interaction were observed for these urea derivatives. However, and of major importance, many of these molecules exhibited promising growth inhibition against Acinetobacter baumannii. In particular, to our delight, the adamantyl urea adduct 3l demonstrated outstanding growth inhibition (94.5%) towards Acinetobacter baumannii. In light of this discovery, molecular docking studies were performed in order to elucidate the binding interaction mechanisms of the most active compounds, as reported herein.

A click chemistry approach for the synthesis of cyclic ureido tethered coumarinyl and 1-aza coumarinyl 1,2,3-triazoles as inhibitors of Mycobacterium tuberculosis H37Rv and their in silico studies.

Nucleoside bases like uracil, pharmacophoric triazoles and benzimidazolones have been used during the present study to design molecular matrices for antitubercular activity, employing Click Chemistry. Click triazoles 4/7/10 have been obtained by the reaction of 4-(Azidomethyl)-2H-chromen-2-ones/quinolin-2(1H)-ones 3 and propargyl ethers 2/6/9 derived from theophylline/6-methyl uracil/2-benzimidazolone respectively. In addition to spectral data structures have been confirmed by single crystal X-ray diffraction studies in case of uracil bis alkyne (6) and theophylline mono triazole (4c). Theophylline linked mono triazoles, 4(a-d) and 6-methyl uracil linked bis triazoles, 7(a-e) have been found to inhibit Mycobacterium tuberculosis H37Rv with MIC values in the range 55.62-115.62 µM. Benzimidazolone bis triazoles, 10(a-n) showed better activity with MIC in the range 2.33-18.34 µM. Molecular modeling studies using Surflex-Dock algorithm supported our results.

Design, synthesis, and molecular docking study of new piperazine derivative as potential antimicrobial agents.

Herein, we describe the successful design and synthesis of seventeen new 1,4-diazinanes, compounds commonly known as piperazines. This group of piperazine derivatives (3a-q) were fully characterized by 1H NMR, 13C NMR, FT-IR, and LCMS spectral techniques. The molecular structure of piperazine derivative (3h) was further established by single crystal X-ray diffraction analysis. All reported compounds were evaluated for their antibacterial and antifungal potential against five bacterial (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa) and two fungal strains (Candida albicans and Cryptococcus neoformans). The complete bacterial screening results are provided. As documented, piperazine derivative 3e performed the best against these bacteria. Additionally, data obtained during molecular docking studies are very encouraging with respect to potential utilization of these compounds to help overcome microbe resistance to pharmaceutical drugs, as explicitly noted in this manuscript.

Click chemistry based regioselective one-pot synthesis of coumarin-3-yl-methyl-1,2,3-triazolyl-1,2,4-triazol-3(4H)-ones as newer potent antitubercular agents.

Coumarin-3-yl-methyl-1,2,3-triazolyl-1,2,4-triazol-3(4H)-ones (8k-z) were synthesized via copper(I)-catalyzed azide-alkyne cycloaddition click chemistry. The synthesized hybrid molecules were characterized by spectral studies. Compounds 8k-z were screened for their in vitro anti-TB activity by using the Microplate Alamar Blue assay and for cytotoxicity using the MTT assay. Some of the compounds were found to be most potent against the tested Mycobacterium tuberculosis H37Rv strain with a MIC of 1.60 µg/ml. Further, docking the compounds into the InhA binding pocket showed strong binding interactions and effective overall docking scores were recorded. The drug-likeness and toxicity studies were computed using Molinspiration and Protox, respectively.

Synthesis, molecular docking studies, and antimicrobial evaluation of new structurally diverse ureas.

A series of new urea derivatives (3a-p) have been synthesized from readily available isocyanates and amines in good to high yields. All synthesized compounds were fully characterized using 1H NMR, 13C NMR, IR, and mass spectrometry. Additionally, the structure of the compound (3n) was confirmed by single-crystal X-ray diffraction. Furthermore, all compounds were evaluated for antimicrobial activity against five bacteria and two fungi. Last but not the least, molecular docking studies with Candida albicans dihydropteroate synthetase were performed and the results are presented herein.

Graph theoretical analysis, in silico modeling, prediction of toxicity, metabolism and synthesis of novel 2-(methyl/phenyl)-3-(4-(5-substituted-1,3,4-oxadiazol-2-yl) phenyl) quinazolin-4(3H)-ones as NMDA receptor inhibitor.

Hit, Lead & Candidate Discovery A variety of novel 2-(methyl/phenyl)-3-(4-(5-substituted-1,3,4-oxadiazol-2-yl)phenyl) quinazolin-4(3H)-ones have been synthesized by treating 3-(4-(5-mercapto-1,3,4-oxadiazol-2-yl)phenyl)-2-(methyl/phenyl)-quinazolin-4(3H)-one with a variety of secondary amines. Graph theoretical analysis was used in identification of drug target that is, NMDAR (N-methyl-d-aspartate receptors). The observed reports of in silico modeling and ligand based toxicity, metabolism prediction studies were encouraging us to synthesize of title compounds and evaluate their antiepileptic effects. The title compounds were tested for its antiepileptic potency by MES and scPTZ model. Rotorod test is used to assess its neurotoxicity. In the preliminary test it was found that in MES test, analogs 6d, 6e, 6f, and 6l were potent; whereas in scPTZ test analogs 6d, 6e, 6f, and 6k displayed potent antiepileptic activity. Additionally these five derivatives were tested in rats orally at a dose of 30 mg/kg and found that compounds 2-methyl-3-(4-(5-morpholino-1,3,4-oxadiazol-2-yl)phenyl)quinazolin-4(3H)-one 6e and 2-methyl-3-(4-(5-(piperidin-1-yl)-1,3,4-oxadiazol-2-yl)phenyl)quinazolin-4(3H)-one 6f exhibited superior activity than reference Phenytoin. In MES test, these derivatives 6e and 6f showed activity at 30 mg/kg i.p. dose after 0.5 hr and 4.0 hr. In scPTZ test these derivatives 6e and 6f showed activity at 100 and 300 mg/kg i.p. dose after 0.5 hr and 4.0 hr, respectively.

Synthesis, molecular modeling and BACE-1 inhibitory study of tetrahydrobenzo[b] pyran derivatives.

ß-Secretase (BACE1) has been broadly documented as one of the possible therapeutic targets for the treatment of Alzheimer's disease. In this paper, we report the synthesis and the for ß-secretase (BACE-1) inhibitory activity of new series of tetrahydrobenzo [b] pyran derivatives. One-pot synthesis of tetrahydrobenzo [b] pyrans was carried out by condensing aromatic aldehyde, malononitrile and 1,3-cyclohexanedione using ionic liquid 1-butyl-3-methyl imidazolium chloride ([bmIm]Cl-) in aqueous alcohol media. The addition of alcohol and water in the ratio of 1:2 keeps all the reactants in solution which facilitates the reaction and makes the product formation very easy. The synthesized compounds were subjected to BACE1 inhibition assay and six compounds, 4d, 4e, 4f, 4h, 4i, and 4p have shown significant IC50 values at micromolar level. Among these six active compounds, 4e was a potential inhibitor with its IC50 value in nanomolar range. All the synthesized compounds were docked onto the active site of ß-Secretase enzyme.

Pharmacophore mapping, molecular docking, chemical synthesis of some novel pyrrolyl benzamide derivatives and evaluation of their inhibitory activity against enoyl-ACP reductase (InhA) and Mycobacterium tuberculosis.

In an effort to produce new lead antimycobacterial compounds, herein we have reported the synthesis of a sequence of new pyrrolyl benzamide derivatives. The new chemical entities were screened to target enoyl-ACP reductase enzyme, which is one of the key enzymes of M. tuberculosis that are involved in type II fatty acid biosynthetic pathway. Compound 3q exhibited H-bonding interactions with Tyr158, Thr196 and co-factor NAD+ that binds the active site of InhA. All the pyrrolyl benzamide compounds were evaluated as inhibitors of M. tuberculosis H37Rv as well as inhibitors of InhA. Among them, few representative compounds were tested for mammalian cell toxicity on the human lung cancer cell-line (A549) and MV cell line that presented no cytotoxicity. Five of these compounds exhibited a good activity against InhA.

Functionalization of 3-chloroformylcoumarin to coumarin Schiff bases using reusable catalyst: an approach to molecular docking and biological studies.

Recently, heterogeneous catalysts have been explored eximiously in the synthesis of heterocyclic compounds. Therefore, here we used solid-supported heterogeneous silica sulfuric acid as a catalyst for the synthesis of Schiff's base of 3-chloroformylcoumarin in view of simplified procedure, reusability and acceptable efficiency, which are required in organic synthesis. An efficient and facile methodology is preferred for synthesis of a class of chromeno-3-substituted derivatives (1a-1l) with good yields. The molecular docking results showed excellent binding interactions with the Mycobacterium tuberculosis InhA-D148G mutant (PDB: 4DQU). The same biomolecules were screened for their in vitro anti-tubercular activity against the M.tb H37Rv strain and antimicrobial studies. Physico-chemistry, toxicity prediction with IC50 value and bioactivity score were also calculated for title compounds. Most active compounds were further tested for cytotoxicity studies and exhibited low-level cytotoxicity against Vero cells. The suggested conjugates are promising lead compounds for the subsequent investigation in search of new anti-tubercular agents. All the conjugates were obtained within the range and followed the Lipinski rule of 5, indicating more 'drug-like' nature.