Person: TATAR, ESRA
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TATAR
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ESRA
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Publication Metadata only Synthesis, and prediction of molecular properties and antimicrobial activity of some acylhydrazones derived from N-(arylsulfonyl)methionine(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2016) TATAR, ESRA; Tatar, Esra; Senkardes, Sevil; Sellitepe, Hasan Erdinc; Kucukguzel, Sukriye Guniz; Karaoglu, Sengul Alpay; Bozdeveci, Arif; De Clercq, Erik; Pannecouque, Christophe; Ben Hadda, Taibi; Kucukguzel, IlkayA series of 38 new acylhydrazones [3-40], derived from (2S)-4-(methylsulfanyl)-2-[[(4-methylphenyl)sulfonyl] amino]butanoic acid hydrazide [2], were synthesized and evaluated for their anti-HIV and antimicrobial activity with the further aim to develop acylhydrazones carrying an amino acid side chain. All tested compounds possess stronger activity against gram (+) bacteria. Compound 23 was found active against methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 3.9 mu g/mL. The MIC value of compound 30 against Enterococcus faecalis, Listeria monocytogenes, and Bacillus cereus was 8 mu g/mL. A computational study for prediction of ADME and drug-like properties (solubility, drug-likeness, and drug score) as well as potential toxicity profiles of compounds 2-40 was performed using the Molinspiration online property calculation toolkit and Osiris Property Explorer. As most of our compounds meet Lipinski's rule of five, they promise good solubility and permeability. According to Osiris calculations, the majority of our compounds are supposed to be nonmutagenic and nonirritating.Publication Metadata only Synthesis and antiproliferative evaluation of novel 2-(4H-1,2,4-triazole-3-ylthio)acetamide derivatives as inducers of apoptosis in cancer cells(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2016) ÖZSAVCI, DERYA; Kulabas, Necla; Tatar, Esra; Ozakpinar, Ozlem Bingol; Ozsavci, Derya; Pannecouque, Christophe; De Clercq, Erik; Kucukguzel, IlkayIn this study, a series of thiosemicarbazide derivatives 12-14, 1,2,4-triazol-3-thione derivatives 15-17 and compounds bearing 2-(4H-1,2,4-triazole-3-ylthio)acetamide structure 18-32 have been synthesized starting from phenolic compounds such as 2-naphthol, paracetamol and thymol. Structures and purity of the target compounds were confirmed by the use of their chromatographic and spectral data besides microanalysis. All of the synthesized new compounds 12-32 were evaluated for their anti-HIV activity. Among these compounds, three representatives 18, 19 and 25 were selected and evaluated by the National Cancer Institute (NCI) against the full panel of 60 human cancer cell lines derived from nine different cancer types. Antiproliferative effects of the selected compounds were demonstrated in human tumor cell lines K-562, A549 and PC-3. These compounds inhibited cell growth assessed by MTT assay. Compound 18,19 and 25 exhibited anti-cancer activity with IC50 values of 5.96 mu M (PC-3 cells), 7.90 mu M (A549/ATCC cells) and 7.71 mu M (K-562 cells), respectively. After the cell viability assay, caspase activation and Bcl-2 activity of the selected compounds were measured and the loss of mitochondrial membrane potential (MMP) was detected. Compounds 18, 19 and 25 showed a significant increase in caspase-3 activity in a dose-dependent manner. This was not observed for caspase-8 activity with compound 18 and 25, while compound 19 was significantly elevated only at the dose of 50 mu M. In addition, all three compounds significantly decreased the mitochondrial membrane potential and expression of Bcl-2. (C) 2016 Elsevier Masson SAS. All rights reserved.Publication Metadata only Fabrication and characterisation studies of cyclodextrin-based nanosponges for sulfamethoxazole delivery(SPRINGER, 2020) TATAR, ESRA; Yasayan, Gokcen; Sert, Betul Satiroglu; Tatar, Esra; Kucukguzel, Ilkaybeta-Cyclodextrin based nanosponges have been synthesized in three molar ratios, and characterized by phase solubility studies, Fourier-transform infrared spectroscopy, matrix-assisted laser desorption/ionization time of flight mass spectrometry, and scanning electron microscopy. Following characterization studies, a model anti-bacterial agent, sulfamethoxazole, has been loaded within the nanosponges, and in vitro drug release studies were carried out. According to results, nanosponges below similar to 100 nm diameter were obtained with a characteristic sponge-like morphology. Phase solubility studies demonstrated that beta-cyclodextrin nanosponges improve solubility of the drug up to 30-fold. These results suggest that nanosponges could improve the bioavailability of drugs by conducing them to reach desired plasma concentrations for therapeutic effect. [GRAPHICS] .Publication Metadata only Synthesis and evaluation of novel 1,3,4-thiadiazole-fluoroquinolone hybrids as antibacterial, antituberculosis, and anticancer agents(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2018) TÜRE, ASLI; Demirci, Asli; Karayel, Kaan Gokce; Tatar, Esra; Oktem Okullu, Sinem; Unubol, Nihan; Tasli, Pakize Neslihan; Kocagoz, Zuhtu Tanil; Sahin, Fikrettin; Kucukguzel, IlkayA series of 5-substituted-1,3,4-thiadiazole-based fluoroquinolone derivatives were designed as potential antibacterial and anticancer agents using a molecular hybridization approach. The target compounds 16-25 were synthesized by reacting the corresponding N-(5-substituted-1,3,4-thiadiazol-2-yl)-2-chloroacetamides with ciprofloxacin or norfloxacin. The purity and identity of the synthesized compounds were determined by the use of chromatographic and spectral techniques (NMR, IR, MS, etc.) besides elemental analysis. Antibacterial, antituberculosis, and anticancer activity of the target compounds were evaluated against selected strains and cancer cell lines. Compound 20 was appreciated as the most active agent representing antibacterial activity against Escherichia coli and Staphylococcus aureus with MIC values of 4 mu g/mL and 2 mu g/mL, respectively. Amongst the synthesized fluoroquinolone derivatives, compounds 19 and 20 were found to have modest antitubercular activity with 8 mu g/mL MIC values for each. Most potent derivative, compound 20 was docked against Staphylococcus aureus and Mycobacterium tuberculosis DNA gyrase enzymes to visualize the possible conformation of the compound. Additionally, anticancer activities of target compounds were evaluated on seven different cancer cell lines.Publication Metadata only Synthesis of some novel heterocyclic compounds derived from diflunisal hydrazide as potential anti-infective and anti-inflammatory agents(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2007) TATAR, ESRA; Kucukguzel, S. Gueniz; Tatar, Esra; Rollas, Sevim; Sahin, Fikrettin; Gulluce, Medine; De Clercq, Erik; Kabasakal, LeventThree novel series of 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid derivatives namely 4-substituted-1,2,4-triazoline-3-thiones (4a-g); 2-substituted- 1.3.4-thiadiazoles (5a-g) and 2-substituted- 1,3,4-oxadiazoles (6a-g) have been synthesized. Twenty-one of the newly synthesized compounds were tested against various bacteria, fungi, yeast species and virus. In addition, we have replaced the carboxylic acid group of diflunisal with heterocycles and the anti-inflammatory activity of heterocycles reported here. Compound (5d) showed activity against Escherichia coli Al and Streptococcuspyogenes ATCC-176 at a concentration of 31.25 mu g/mL, whereas cefepime, the drug used as standard, has been found less active against the bacteria mentioned above. Compound (4b) has exhibited activity against Aspergillus variecolor and Trichophyton rubrum at a concentration of 31.25 and 15.25 mu g/mL, whereas Amphotericin B, the drug used as standard, has been found less active against the yeast and fungi. The highest antiviral activity was found in the 1,3,4-thiadiazole derivative (5a) having a methyl group at 2nd position against Sindbis virus at 9.6 mu g/mL. Compound (4c) exhibited the highest anti-inflammatory activity (73.03%) whereas diflunisal, the drug used as standard, has been found less active (24.16%). Compound (5f) presented similar antinociceptive activity with the standard drug (paw withdrawal latency was 19.21 s compared to that of diflunisal which was 19.14 s, in hot plate test). (c) 2007 Elsevier Masson SAS. All fights reserved.Publication Metadata only Novel 4-Thiazolidinones as Non-Nucleoside Inhibitors of Hepatitis C Virus NS5B RNA-Dependent RNA Polymerase(WILEY-V C H VERLAG GMBH, 2015) TATAR, ESRA; Cakir, Gizem; Kucukguzel, Ilkay; Guhamazumder, Rupa; Tatar, Esra; Manvar, Dinesh; Basu, Amartya; Patel, Bhargav A.; Zia, Javairia; Talele, Tanaji T.; Kaushik-Basu, NeerjaIn continuation of our efforts to develop new derivatives as hepatitis C virus (HCV) NS5B inhibitors, we synthesized novel 5-arylidene-4-thiazolidinones. The novel compounds 29-42, together with their synthetic precursors 22-28, were tested for HCV NS5B inhibitory activity; 12 of these compounds displayed IC50 values between 25.3 and 54.1 mu M. Compound 33, an arylidene derivative, was found to be the most active compound in this series with an IC50 value of 25.3 mu M. Molecular docking studies were performed on the thumb pocket-II of NS5B to postulate the binding mode for these compounds.Publication Metadata only Synthesis and Biological Activity of N-(arylsulfonyl) Valine Hydrazones and Assistance of NMR Spectroscopy for Definitive 3D Structure(BENTHAM SCIENCE PUBL LTD, 2019) TATAR, ESRA; Senkardes, Sevil; Tatar, Esra; Nepravishta, Ridvan; Cela, Dorisa; Paci, Maurizio; Ozakpinar, Ozlem Bingol; Sekerler, Turgut; De Clercq, Erik; Pannecouque, Christophe; Kucukguzel, S. Guniz; Kucukguzel, IlkayBackground: Hydrazide-hydrazones constitute an important class of compounds for new drug development. In this study, a series of 39 new acylhydrazones (3-41), derived from (2S)-3-methyl-2-[[( 4-methylphenyl)sulfonyl]amino]butanoic acid hydrazide were synthesized with further aim to achieve biologically active acylhydrazones carrying an amino acid side chain. Methods: Compounds 3-41 were synthesized by microwave-assisted method. All synthesized compounds have been tested for their anti-HIV activity compound 21 was subjected to a new set of 2D-NMR analysis for the characterization of the isomers in solution and determination of its 3D structure. Results: The IC50 values for compounds 2-40 were found between >125-10.90 mu g/ml against HIV-1( IIIB) and HIV-2(ROD) strains in MT-4 cells. Compounds 3, 6, 10, 12, 23, 24, 27, 32, and 37 with CC50 values between 10.90-14.50 mu g/ml were selected to evaluate for their antileukemia activity. IC50 values for these mentioned compounds were found as >100 mu M on human chronic myelogenous leukemia, K562 cell line. Conclusion: Some compounds with IC50 values between 10.90-14.50 mu g/ml will be of benefit in the development of novel leads.Publication Metadata only Some Hydrazones of 2-Aroylamino-3-methylbutanohydrazide: Synthesis, Molecular Modeling Studies, and Identification as Stereoselective Inhibitors of HIV-1(WILEY-V C H VERLAG GMBH, 2013) TATAR, ESRA; Tatar, Esra; Kucukguzel, Ilkay; Daelemans, Dirk; Talele, Tanaji T.; Kaushik-Basu, Neerja; De Clercq, Erik; Pannecouque, ChristopheIn accordance with our antiviral drug development attempt, acylhydrazone derivatives bearing amino acid side chains were synthesized for the evaluation of their antiviral activity against various types of viruses. Among these compounds, 8S, 11S, and 12S showed anti-HIV-1 activity with a 50% inhibitory concentration (IC50)=123.8 mu M (selectivity index, SI>3), IC50=12.1 mu M (SI>29), IC50=17.4 mu M (SI>19), respectively. Enantiomers 8R, 11R, and 12R were inactive against the HIV-1 strain IIIB. Hydrazones 8S, 11S, and 12S which were active against HIV-1 wild type showed no inhibition against a double mutant NNRTI-resistant strain (K103N;Y181C). Molecular docking calculations of R- and S-enantiomers of 8, 11, and 12 were performed using the hydrazone-bound novel site of HIV-1 RT.Publication Metadata only Synthesis and characterization of flurbiprofen hydrazide derivatives as potential anti-HCV, anticancer and antimicrobial agents(SPRINGER BIRKHAUSER, 2013) TATAR, ESRA; Cikla, Pelin; Tatar, Esra; Kucukguzel, Ilkay; Sahin, Fikrettin; Yurdakul, Dilsad; Basu, Amartya; Krishnan, Ramalingam; Nichols, Daniel Brian; Kaushik-Basu, Neerja; Kucukguzel, S. GunizA novel series of new flurbiprofen hydrazide derivatives 2-(2-fluorobiphenyl-4-yl)-N'-[(substituted phenyl/5-nitro-2-furyl)methylene]propanehydrazide (3a-k), 2-(2-fluorobiphenyl-4-yl)-N-(2-substituted-4-oxo-1,3-thiazolidine-3-yl)propanamide (4a-b, 4d-k), 2-[2-(2-fluorobiphenyl-4-yl) propanoyl]-N-substituted hydrazinecarbothioamide (5a-h) and 2-(2-fluorobiphenyl-4-yl)-N'-[(3-methyl-4-oxo-1,3-thiazolidin-2-ylidene]propanehydrazide (6a-b, 6e and 6g) has been synthesized in this study. All synthesized compounds were screened for antimicrobial activity against various bacterial and fungal strains. Additionally, compounds were evaluated for the ability to inhibit Hepatitis C virus NS5B polymerase. The most active 4-thiazolidinone compound was 4k (SGK119) with 67.0 % and thiosemicarbazide compound was 5d (SGK123) with 69.50 % inhibition at 200 mu M against hepatitis C virus NS5B RNA polymerase. Anticancer activity of the selected compounds (3i, 3j, 3h, 4d, 4i and 6b) was determined at a single dose towards the full panel of 60 human cancer cell lines by the National Cancer Institute (NCI). 2-(2-Fluoro-4-biphenylyl)-N-[2-[4-(trifluoromethyl)phenyl]-4-oxo-1,3-thiazolidine-3-yl]propanamide 4d, containing thiazolidinone ring, demonstrated the most marked effect with 20.80 % growth percent on leukaemia cancer cell line SR at 10(-5) M. The results demonstrated that none of the compounds tested have anticandidal and antifungal activities, but two of them (4a and 4i) showed antibacterial inhibition against Micrococcus luteus, and Staphylococcus cohnii and Staphylococcus aureus, respectively.Publication Metadata only Synthesis and structure-activity relationship of L-methionine-coupled 1,3,4-thiadiazole derivatives with activity against influenza virus(WILEY) TATAR, ESRA; Tatar, Esra; Yaldiz, Seda; Kulabas, Necla; Vanderlinden, Evelien; Naesens, Lieve; Kucukguzel, IlkayIn previous investigations, we identified a class of 1,3,4-thiadiazole derivatives with antiviral activity. N-{3-(Methylsulfanyl)-1-[5-(phenylamino)-1,3,4-thiadiazole-2-yl]propyl}benzamide emerged as a relevant lead compound for designing novel influenza A virus inhibitors. In the present study, we elaborated on this initial lead by performing chemical synthesis and antiviral evaluation of a series of structural analogues. During this research, thirteen novel 1,3,4-thiadiazole derivatives were synthesized by the cyclization of the corresponding thiosemicarbazides as synthetic precursors. The structures and the purities of the synthesized compounds were confirmed through chromatographic and spectral data. Four L-methionine-based 1,3,4-thiadiazole derivatives displayed activity against influenza A virus, the two best compounds being 24 carrying a 5-(4-chlorophenylamino)-1,3,4-thiadiazole moiety and 30 possessing a 5-(benzoylamino)-1,3,4-thiadiazole structure [antiviral EC50 against influenza A/H3N2 virus: 4.8 and 7.4 mu M, respectively]. The 1,3,4-thiadiazole derivatives were inactive against influenza B virus and a wide panel of unrelated DNA and RNA viruses. Compound 24 represents a new class of selective influenza A virus inhibitors acting during the virus entry process, as evidenced by our findings in a time-of-addition assay. Molecular descriptors and in silico prediction of ADMET properties of the active compounds were calculated. According to in silico ADMET and drug similarity studies, active compounds have been estimated to be good candidates for oral administration with no apparent toxicity considerations.