Öznur Ateş

Synthesis and antitubercular activity of 4-(3-coumarinyl)-3-cyclohexyl-4-thiazolin-2-one benzylidenehydrazones

In this study, a new series of 4-(3-coumarinyl)-3-cyclohexyl-4-thiazoline-2-one benzylidene hydrazones (3a-p) were synthesized. Structures of the title compounds were determined by analytical and spectral methods. 3a-p were evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv.

Synthesis of Mannich Bases of Some 2,5-Disubstituted 4-Thiazolidinones and Evaluation of Their Antimicrobial Activities

5‐Phenyl/methyl‐5‐morpholinomethyl/pyrrolidinomethyl‐2‐(5‐aryl‐1,3,4‐oxadiazol‐2‐yl) imino]‐4‐thiazolidinones (5a—m) were synthesized by the reaction of 5‐phenyl/methyl‐2‐[(5‐aryl‐1,3,4‐oxadiazol‐2‐yl)imino]‐4‐thiazolidinones (4a—j) with formaldehyde and morpholine or pyrrolidine. The structures of the compounds were determined by analytical and spectral (IR, 1H‐NMR, EIMS) methods. The antibacterial activities of the novel compounds against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri and Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 were tested using the disk diffusion method. Compounds 5a, 5b, 5c, 5e, 5g, and 5h were found to be active against S. aureus ATCC 6538 (MIC: 312.5; 39; 19.5; 39; 156; and 78 μg/mL respectively) and compounds 5c and 5h against S. flexneri (MIC: both 312.5 μg/mL). The minimal inhibitory concentrations of these compounds were determined using the micro dilution method.

Synthesis and antimicrobial activity of some 5-aryl-2-[(N, N-disubstituted thiocarbamoylthio)acylamino]-1,3,4-oxadiazoles

In this study, a number of novel 5-aryl-2-[(N,N-disubstituted thiocarbamoylthio)acylamino]-1,3,4-oxadiazole derivatives were synthesized by the reaction of potassium salts of N,N-disubstituted dithiocarbamoic acids with 2-[(alpha-chloro-alpha-phenylacetyl/alpha-bromopropionyl)-amino]-5 -aryl-1, 3,4-oxadiazoles. Structures of the compounds were confirmed by the spectral data (IR, 1H NMR, EIMS) and elemental analyses. Most of the compounds were tested against various microorganisms and four of them were found to be weakly active against Staphylococcus aureus and Staphylococcus epidermidis.

Synthesis and evaluation of antibacterial activity of some 2-[[α-(4-substituted benzoyloxy)-α-phenylacetyl or methylacetyl]amino]-5-(4-methoxyphenyl)-1,3,4-oxadiazoles

Abstract In this study, a new series of 2-[[α-(4-substitutedbenzoyloxy)-α-phenylacetyl or methylacetyl]amino]-5-(4-methoxyphenyl)-1,3,4-oxadiazoles were obtained by condensation of 2-[(α-chloro-α-phenylacetyl or α-bromopropionyl)amino]-5-(4-methoxyphenyl)-1,3,4-oxadiazoles with sodium salts of 4-substituted benzoic acids. Structures of the compounds were assigned on the basis of spectral data (UV, IR, 1H NMR, EI MS) and elemental analyses. The antibacterial activities of the novel compounds against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri and Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 were tested using disk diffusion method. Compounds 4a, 4d and 4g were found to be active against S. aureus ATCC 6538 (MIC, 78, 39 and 78 μg ml−1, respectively) and compound 4e against S. epidermidis ATCC 12228 (MIC, 156 μg ml−1).

Synthesis, Characterization, and Evaluation of Antimicrobial Activity of Some 1,2,4-Triazole Derivatives Bearing an Antipyryl Moiety

Summary. Some novel 4-[[2-[[5-(2-furanyl)-4-alkyl/aryl-4H-1,2,4-triazol-3-yl]thio]-acetyl/propionyl]-amino]-1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazoles were synthesized and evaluated for in vitro antibacterial activity against Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, and Enterococcus faecalis ATCC 29212 and antifungal activity against Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258, Candida parapsilosis, Trichophyton mentagrophytes var. erinacei NCPF 375, Microsporum gypseum NCPF 580, and Trichophyton rubrum using the microbroth dilution method. All of the compounds were found to be ineffective against the above bacteria within the applied MIC ranges. On the other hand, they were effective against fungi to different degrees. Three compounds showed high activity against C. parapsilosis and T. mentagrophytes var. erinacei NCPF 375 (MIC = 8 μg cm−3). The in vitro antimycobacterial activity of the new compounds was also investigated against Mycobacterium tuberculosis H37RV (ATCC 27294) in BACTEC 12B medium using a broth microdilution assay, the Microplate Alamar Blue Assay (MABA). Compounds exhibiting fluorescence were tested in the BACTEC 460 radiometric system. The most active compound was found with 66% inhibition at >6.25 μg cm−3.