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The mutations concerned with non-small cell lung cancer involving epidermal growth factor receptor of tyrosine kinase family have primarily targeted. EGFR inhibitors binding allosterically to C797S mutant EGFR enzyme have been developed. Here, database building, library screening performing R-group enumeration and scaffold hopping technique for increasing the EGFR binding affinity of compounds have been carried out. Virtual screening was performed subjecting to HTVS, SP and XP docking protocol along with its relative binding free energy calculations. Molecular docking studies provided the information about binding pockets and interactions of molecules on mutant (PDB: 5D41) as well as wild type (PDB: 4I23) EGFR enzyme. This was supported with ADMET and molecular simulation studies. On the basis of glide score and protein-ligand interactions, highest scoring molecule was selected for molecular dynamic simulation providing a complete insight into the conformational stability. The virtually screened molecules can act as potential EGFR inhibitors in the management of drug resistance. Communicated by Ramaswamy H. Sarma.

Series of novel N-benzyl derivatives of 6-aminoflavone (9a–n) were synthesized and evaluated for anticancer and topoisomerase II enzyme inhibition activity. All the synthesized compounds were screened for in vitro anticancer activity against human breast cancer cell line (MCF-7) and human lung cancer cell line (A-549). Among the synthesized compounds, 9f and 9g were found to be the most potent anticancer agents against human breast cancer cell line (MCF-7) with IC50 values of 9.35 µM and 9.58 µM, respectively. Compounds 9b, 9c and 9n exhibited promising anticancer activity against human lung cancer cell line (A-549) with 43.71%, 46.48% and 44.26% inhibition at the highest concentration of 10 µM, respectively. Compounds 9c, 9f and 9g have ability to inhibit the topoisomerase II enzyme. Compound 9f showed most potent topoisomerase II enzyme inhibition activity with IC50 value of 12.11 µM. Further, these compounds have a high potential to be developed as a promising topoisomerase II inhibitors.

Background A small library of quinazolin-4-one clubbed thiazole acetates/acetamides lacking toxicity-producing functionalities was designed, synthesized, and evaluated for antidiabetic potential as glucokinase activators (GKA). Molecular docking studies were done in the allosteric site of the human glucokinase (PDB ID: 1V4S) enzyme to assess the binding mode and interactions of synthesized hits for best-fit conformations. All the compounds were evaluated by in vitro enzymatic assay for GK activation. Results Data showed that compounds 3 (EC50 = 632 nM) and 4 (EC50 = 516 nM) showed maximum GK activation compared to the standards RO-281675 and piragliatin. Based on the results of the in vitro enzyme assay, docking studies, and substitution pattern, selected compounds were tested for their glucose-lowering effect in vivo by oral glucose tolerance test (OGTT) in normal rats. Compounds 3 (133 mg/dL) and 4 (135 mg/dL) exhibited prominent activity by lowering the glucose level to almost normal, eliciting the results in parallel to enzyme assay and docking studies. Binding free energy, hydrogen bonding, and π–π interactions of most active quinazolin-4-one derivatives 3 and 4 with key amino acid residues of the 1V4S enzyme were studied precisely. Preliminary in-silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) prediction was carried out using SwissADME and PreADMET online software which revealed that all the compounds have the potential to become orally active antidiabetic agents as they obeyed Lipinski's rule of five. Conclusion The results revealed that the designed lead could be significant for the strategic design of safe, effective, and orally bioavailable quinazolinone derivatives as glucokinase activators.

The inhibition of D-alanine-D-alanine ligase (Ddl) prevents bacterial growth, which makes this enzyme an attractive and viable target in the urgent search for novel effective antimicrobial drugs. In this work, a series of novel coumarin-linked pyrazoline inhibitors of D-alanine-D-alanine ligase were synthesized and evaluated as inhibitors of Escherichia coli DdlB ligase in order to target resistant strains of bacteria using environmentally benevolent β-cyclodextrin as a supramolecular catalyst via one-pot four component synthesis in water as a green reaction media. All the newly synthesized compounds have been characterized by elemental analysis and various spectroscopic methods. The new procedure has noteworthy advantages including easy work-up, short reaction times, high yields of products and column-free synthesis. The synthesized compounds were evaluated in vitro for their antimicrobial activity. Among the synthesized compounds, namely 3-(5-(4-hydroxy-3-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)-2H-chromen-2-one (5f) was found to be the most potent D-alanine-D-alanine ligase enzyme inhibitor, with an IC50 value 106 μM, and the compound 3-(5-(p-tolyl)-4,5-dihydro-1H-pyrazol-3-yl)-2H-chromen-2-one (5g) was found to be the second-most potent inhibitor of the DdlB enzyme, with an IC50 value 111 μM against the standard D-cycloserine. In addition, SAR study provided evidence that the –OH, –CH3 and –OCH3 groups at the 4- and 3-position of the coumarins linked to the pyrazolines scaffold increased enzymatic inhibition, while the molecular docking study of most active compounds 5a, 5g, and 5j against DdlB enzyme of E. coli exhibited good binding properties. This work thus highlights the coumarin-linked pyrazoline motif as a very promising tool for the development of novel antimicrobial compounds acting through an interesting bactericidal mechanism of action.

Metabolism is one of the prime reasons where most of drugs fail to accomplish their clinical trials. The enzyme CYP3A4, which belongs to the superfamily of cytochrome P450 enzymes (CYP), helps in the metabolism of a large number of drugs in the body. The enzyme CYP3A4 catalyzes oxidative chemical processes and shows a very broad range of ligand specificity. The understanding of the compound&rsquo, s structure where oxidation would take place is crucial for the successful modification of molecules to avoid unwanted metabolism and to increase its bioavailability. For this reason, it is required to know the site of metabolism (SOM) of the compounds, where compounds undergo enzymatic oxidation. It can be identified by predicting the accessibility of the substrate&rsquo, s atom toward oxygenated Fe atom of heme in a CYP protein. The CYP3A4 enzyme is highly flexible and can take significantly different conformations depending on the ligand with which it is being bound. To predict the accessibility of substrate atoms to the heme iron, conventional protein-rigid docking methods failed due to the high flexibility of the CYP3A4 protein. Herein, we demonstrated and compared the ability of the Glide extra precision (XP) and Induced Fit docking (IFD) tool of Schrodinger software suite to reproduce the binding mode of co-crystallized ligands into six X-ray crystallographic structures. We extend our studies toward the prediction of SOM for compounds whose experimental SOM is reported but the ligand-enzyme complex crystal structure is not available in the Protein Data Bank (PDB). The quality and accuracy of Glide XP and IFD was determined by calculating RMSD of docked ligands over the corresponding co-crystallized bound ligand and by measuring the distance between the SOM of the ligand and Fe atom of heme. It was observed that IFD reproduces the exact binding mode of available co-crystallized structures and correctly predicted the SOM of experimentally reported compounds. Our approach using IFD with multiple conformer structures of CYP3A4 will be one of the effective methods for SOM prediction.

Background Due to the need and adverse effects associated with the available anti-inflammatory agents, an attempt was made to develop the new anti-inflammatory agents with better activity and lesser adverse effects. Objective Synthetic approaches based on chemical modification of NSAIDs have been undertaken with the aim of improving NSAIDs safety profile. Method In the present study, a series of thiazole derivatives (3a-3x) was synthesized and tested for its anti-inflammatory with analgesic and nitric oxide releasing properties. In this work, synthesis of molecules containing substituted diaryl ring on 5-membered thiazole ring with nitric oxide releasing moiety is described. Results Out of the twenty four synthesized compounds, five compounds showed considerable anti-inflammatory and analgesic activity in comparison with the standard. Most of the synthesized compounds showed considerable nitric oxide-releasing property. The molecular docking study was used to rationalize binding interaction at the active site and the result showed good binding interaction. Conclusion From the results of pharmacological studies, we conclude that the synthesized compounds have not only retained, but showed enhanced anti-inflammatory and analgesic profile.

The present method provides a wide scope and quick access to dihydropyrido[2,3-d:6,5-d′]dipyrimidinetetraone and pyrimido[4,5-d]pyrimidine derivatives in good to excellent isolated yields from a one-pot three-component reaction of aldehydes, barbituric acid and ammonium acetate/urea in DIPEAc at room temperature. Major advantages of the present methodology are: use of green solvent, short reaction time, catalyst free, compatibility with a wide range of substrates, ease of recovery, reusability of the reaction medium, and DIPEAc as an alternative solvent and catalyst. All the synthesized compounds (3a–k) and (4a–g) were evaluated for their in vitro anticancer and tyrosinase inhibitory activity. In vitro anticancer screening of the synthesized compounds was performed against MCF-7, HeLa and A-549 cancer cell lines and 3f, 3h and 3i showed good activity. The compounds 3a, 3c, 3f and 3i showed good in vitro anticancer activity against SK-MEL-2. The synthesized compounds were also tested on non-tumorigenic MCF-10A cell lines and were found to be selective towards their cancer cell lines. At the IC50 concentration of compound 3f there were typical morphological changes such as cell wall deformation, cell detachment, cell shrinkage and a reduced number of viable cells in MCF-7 cancer cell lines in comparison to control cells. Among the series, compounds 3f, 3h and 3i excellently inhibited the tyrosinase enzyme. A molecular docking study of the compounds was also performed and compounds showed overall very effective binding modes and good agglomeration in the active site by forming various interactions with active site residues. The in silico ADMET properties of the synthesized compounds showed that they possess worthy oral drug like properties.

A library of novel flavonoid derivatives with diverse heterocyclic groups was designed and efficiently synthesized. Structures of the newly synthesized compounds 4a-i and 8a-l have been characterized by 1H NMR, 13C NMR, MS and elemental analysis. Anticancer activities were evaluated against MCF-7, A549, HepG2 and MCF-10A by MTT based assay. Compared with the positive control Adriamycin, compounds 4a, 4b, 4c, 4d, 8d, 8e and 8j were found to be most active anti-proliferative compounds against human cancer cell line. We found that compounds 4a and 4c exhibited inhibition of enzyme topoisomerase II with IC50 values 10.28 and 12.38 μM, respectively. In silico docking study of synthesized compounds showed that compounds 4a and 4c have good binding affinity toward topoisomerase IIα enzyme and have placed in between DNA base pair at active site of enzyme. In silico ADME prediction results that flavonoid coumarin analogues 4a-i could be exploited as an oral drug candidate.

An approach is described to access 1,2,3-triazole-derived peptidyl vinyl sulfones as Trypanosoma brucei brucei inhibitors by using click chemistry, starting from a common azide intermediate. Among the triazole analogues, biotinylated inhibitors 11 and 12 offer possibilities as probes for the elucidation of target proteases for this compound class. The development of two syntheses of a 1,2,3-triazole-based vinyl sulfone 5 are also presented. This compound was accessed through a click reaction of a lysine-derived azide (itself accessed by diazo transfer), and a phenylalanine-derived alkyne synthesised by both Ohira–Bestmann and Corey–Fuchs-based alkynylation protocols. Several members of this family of compounds showed promising anti-trypanosomal activity. Unexpectedly, one of the most active compounds was allyl sulfone 24, which stems from the isomerisation of vinyl sulfone 5, and is presumably a reversible inhibitor. A docking study of the analogues in the active site of the parasitic cysteine protease rhodesain was carried out in order to gain an insight into their likely interactions with these enzymes.

A series of hetero-substituted sulphonamido-benzamide derivatives which can activate glucokinase (GK) were synthesized and screened in-vitro using Human GK activation assay and in-vivo following oral glucose tolerance test (OGTT) assays. All the molecules were docked into the active site of 1V4S receptor grid by XP docking method utilizing Schrodinger software to assess the binding interactions. Compounds 12 (EC50 = 495 nM) and 15 (EC50 = 522 nM), revealed maximum in-vitro GK activation. Selected compounds were subjected for in-vivo OGTT assay. The data revealed that same compounds 12 (135 mg/dL) showed maximum reduction in blood glucose level followed by compound 15 (142 mg/dL) at 120 min. The docking results as glide score, binding energy and interactions were reported and compounds with maximum pharmacological activity were studied precisely. In-silico ADME parameters, pharmacokinetic properties and toxicity studies were carried out and all compounds were found to have good bioavailability and nontoxic. Overall, the series of hetero-substituted sulphonamido-benzamide hybrids are safe and could be explored further for better therapeutic efficacy as GK activators.

In search of new active molecules against MCF-7, A549 and HepG2, tetrazole based pyrazoline and isoxazoline derivatives under both conventional and ultrasonic irradiation method were designed and efficiently synthesized. Structures of newly synthesized compounds 5a-h and 6a-h were characterized by 1H NMR, 13C NMR, MS and elemental analysis. Several derivatives were found to be excellent cytotoxic against MCF-7, A549 and HepG2 cell lines characterized by lower IC50 values (0.78–3.12 µg/mL). Compounds 5b and 5c demonstrated an antiproliferative effect comparable to that of CA-4. Western blot analysis revealed that, reported compounds accumulate more tubulin in the soluble fraction. Docking studies suggested that, binding of these compounds mimics at the colchicine site of tubulin. In vitro study revealed that the tetrazole based pyrazolines and isoxazolines may possess ideal structural requirements for further development of novel therapeutic agents.

A series of new sulfonamide analogues of 6/7-aminoflavones were synthesized by using molecular hybridization approach. These new sulfonamide analogues were screened for antiproliferative activity against human hepatocellular carcinoma (HepG-2), human lung cancer cell line (A-549), human colorectal adenocarcinoma (Caco-2) cancer cell lines. Compounds 5p, 5q, 5t, 5v, 5w and 5x exhibited good anticancer activity against selected cancer cell lines. These compounds were further evaluated to predict their ability to inhibit topoisomerase-II enzyme. Compound 5x has shown potent antiproliferative activity (IC50 value 0.98 µM) as compared to standard drug Adriamycin (IC50 = 0.94 µM) indicating that these compounds exhibits anticancer activity via inhibition of topoisomerase-II enzyme. Docking results also have supported above observations by indicating that compounds are held in the active pocket by combination of various hydrogen and hydrophobic interactions with Top II-DNA-etoposide enzyme.

Non-nucleoside reverse transcriptase inhibitors have a definitive role and most commonly used in treatment of HIV-1 infection. A new series of 4-ethylidene/substituted-benzylidene-1-(4-hydroxy/chloro-6-methylpyrimidin-2-yl)-2-ethyl/phenyl-1H-imidazol-5(4H)-one were designed, synthesized, and evaluated for HIV-1 reverse transcriptase (RT) inhibitory activity. The results of in-vitro HIV-1 RT assay showed that some of the new compounds, such as 4c, 4d, 4e, 5a, and 5e effectively inhibit HIV-1 RT activity. 1-(4-Chloro-6-methylpyrimidin-2-yl)-4-(furan-2-ylmethylene)-2-methyl-1H-imidazol-5(4H)-one (5e) exerted most potent in-vitro HIV-1 RT inhibitory activity, among the group of compounds. Molecular docking studies were carried out to explore the binding affinity of imidazole-5-one analogs in active site of HIV-1 RT enzyme.

Synthesis of new series of 1,2,4-triazole with 1,2,3-triazole and piperidine ring using ZrOCl(2) ·8H(2) O as a catalyst in ethanol has been described. The yields obtained are in the range of 80-85%. All the synthesized compounds (3a-3o) are novel and were evaluated for their in vitro antifungal activities using standard agar method. Docking study of the newly synthesized compounds was performed, and results showed that all new compounds have similar binding mode in the active site of fungal enzyme P450 cytochrome lanosterol 14α-demethylase.

Tumor necrosis factor-α (TNF-α) converting enzyme (TACE) has been considered one of the principal therapeutic targets for the treatment of TNF-dependent pathologies. Several TACE inhibitors have been reported, but none of them has been successfully passed to phase II clinical trials. In the present work, we attempted to design highly selective new non-hydroxamate sulfonamide TACE inhibitors. The docking study was performed on one of the crystal structures of TACE, selected based on its resolution and R value, to tackle the flexibility issue of the active site. The results allowed us to distinguish the analogues with a higher binding affinity toward the active site of TACE and to identify the substituent of analogues needed for binding with the surrounding site of the enzyme. Finally the analogues were docked on crystal structures of six different matrix metalloproteinases (MMPs) for a selectivity study of TACE over MMPs. Some of these analogues were synthesized and subjected to preliminary testing for in vivo anti-inflammatory activity and TACE inhibitory activity.

Herein, we report an environmentally friendly, rapid, and convenient one-pot ultrasound-promoted synthesis of 5-amino-2-(4-chlorophenyl)-7-substituted phenyl-8,8a-dihydro-7H-(1,3,4)thiadiazolo(3,2-α)pyrimidine-6-carbonitrile derivatives. The in-vitro anticancer activities of these compounds were evaluated against four human tumor cell lines. Among all the synthesized derivatives, compound 4i, which has substituent 3-hydroxy-4-methoxyphenyl is found to have the highest GI50 value of 32.7 μM, 55.3 μM, 34.3 μM, 28.9 μM for MCF-7, K562, HeLa and PC-3 cancer cell lines respectively. A docking study of the newly synthesized compounds were performed, and the results showed good binding mode in the active site of thymidylate synthase enzyme. ADME properties of synthesized compounds were also studied and showed good drug like properties The authors are thankful to the Fatima Rafiq Zakaria Chairman Maulana Azad Educational Trust and Zahid Zaheer, Incharge Principal, Y.B. Chavan College of Pharmacy, Rafiq Zakaria Campus, Aurangabad 431 001 (M.S.), India for providing the laboratory facility. In vitro SRB assay for anti-cancer activity evaluation of drugs was performed at Anti-Cancer Drug screening facility (ACDSF) at ACTREC, Tata Memorial Centre, Navi Mumbai and the authors are greatful to Jyoti Kode for her cooperation in in-vitro studies SI

We present here the Energetic pharmacophore model representing complementary features of the 1,2,3,4-tetrahydropyrimidine for selective cyclooxygenase-2 (COX-2) inhibition. For the development of pharmacophore hypothesis, a total of 43 previously reported compounds were docked on active site of COX-2 enzyme. The generated pharmacophore features were ranked using energetic terms of Glide XP docking for 1,2,3,4-tetrahydropyrimidine scaffold to optimize its structure requirement for COX-2 inhibition. The thirty new 4,5,6-triphenyl-1,2,3,4-tetrahydropyrimidine derivatives were synthesized and assessed for selective COX-2 inhibitory activity. Two compounds 4B1 and 4B11 were found to be potent and selective COX-2 inhibitors. The molecular docking studies revealed that the newly synthesized compounds can be docked into COX-2 binding site and also provide the molecular basis for their activity.