Nuray Ulusoy

Synthesis and antimicrobial activity of some 1,2,4-triazole-3-mercaptoacetic acid derivatives

Ethyl 5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetate (2), 5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetic acid hydrazide (3) and a series of new N-alkylidene/arylidene-5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetic acid hydrazides (4a-f) were synthesized and evaluated for in vitro antibacterial activity against Staphylococcus aureus ATCC 6538. Staphylococcus epidermidis ATCC 12228, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Escherichia coli ATCC 8739, Shigella flexneri, Salmonella typhi, Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 using the disk diffusion and microdilution methods. Compound 4f showed antibacterial activity against some bacteria. The in vitro antimycobacterial activity of the new compounds against Mycobacterium tuberculosis H37Rv was evaluated employing the BACTEC 460 radiometric system. The highest inhibition observed was 61% at > 6.25 microg/ml.

New 6-Phenylimidazo[2,1-b]thiazole Derivatives: Synthesis and Antifungal Activity

Summary. New benzylidene-(6-phenylimidazo[2,1-b]thiazol-3-yl)-acetic acid hydrazides, 4-alkyl-1-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetyl)-3-thiosemicarbazides, 2-aryl-3-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetamido)-4-thiazolidinones, and 3-alkyl-2-(((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinones were synthesized from 6-phenylimidazo[2,1-b]thiazole-3-acetic acid hydrazide and evaluated for antifungal activity against three dermatophyte strains using ketoconazole as standard. Several of them were found as effective as the standard against Trichophyton rubrum and Microsporum audounii (MIC=6 μg/cm3), whereas the activity of N-benzylidene-(6-phenylimidazo[2,1-b]-thiazol-3-yl)-acetic acid hydrazide against M. audounii was superior to the standard (MIC=3 μg/cm3). 2-(4-Methylphenyl)-3-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetamido)-4-thiazolidinone and 2-(4-chlorophenyl)-3-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetamido)-4-thiazolidinone showed the highest activity against Trichophyton mentagrophytes var. erinacei NCPF-375 (MIC=3 μg/cm3).Zusammenfassung. Ausgehend von 6-Phenylimidazo[2,1-b]-thiazol-3-essigsäurehydrazid wurden neue Benzyliden-(6-phenylimidazo-[2,1-b]-thiazol-3-yl)-essigsäurehydrazide, 4-Alkyl-1-((6-phenylimidazo[2,1-b])thiazol-3-yl)-acetyl)-3-thiosemicarbazide, 2-Aryl-3-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetamido)-4-thiazolidinone und 3-Alkyl-2-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinone dargestellt und hinsichtlich ihrer fungistatischen Aktivität untersucht. Einige der Verbindungen erwiesen sich als aktiv gegen Trichophyton rubrum und Microsporum audounii (MIC=6 μg/cm3). Es stellte sich heraus, daß N-benzyliden-(6-phenylimidazo[2,1-b]-thiazol-3-yl)-essigsäurehydrazide gegen M. audounii aktiver als die Standardsubstanz Ketokonazol ist (MIC=3 μg/cm3). 2-(4-Methylphenyl)-3-((6-phenylimidazo[2,1-b])thiazol-3-yl)-acetamido)-4-thiazolidinon und 2-(4-Chlorophenyl)-3-((6-phenylimidazo[2,1-b]thiazol-3-yl)-acetamido)-4-thiazolidinon zeigen die größte Aktivität gegen Trichophyton mentagrophytes var. erinacei NCPF-375 (MIC=3 μg/cm3).

5-Nitroimidazole derivatives as possible antibacterial and antifungal agents

Some novel 1-[2-[[5-(2-furanyl)-4-substituted 4H-1,2,4-triazol-3-yl[thio[ethyl[-2-methyl-5-nitro-1H-imidazoles (3), 1-[3-[[5-(2-furanyl/2-thienyl)-4-substituted 4H-1,2,4-triazol-3-yl[-thio]-2-hydroxypropyl[-2-methyl-5-nitro-1H- imidazoles (5) and 1-[3-[(N,N-disubstituted thiocarbamoyl)-thio[-2-hydroxypropyl]-2-methyl-5-nitro-1H-imidazoles (7) were synthesized and evaluated for in vitro antibacterial and antifungal activity. Some of 5 were found to be effective against bacteria and fungi (minimum inhibitory concentration (MIC) 7.3-125 micrograms/ml), whereas 7 were found to be effective against fungi (MIC 3-25 micrograms/ml).

New 6-(4-Bromophenyl)-imidazo[2,1-b]thiazole Derivatives: Synthesis and Antimicrobial Activity

Summary. New 4-alkyl/aryl-1-((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-3-thiosemicarbazides and 3-alkyl/aryl-2-(((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinones were synthesized from 6-(4-bromophenyl)-imidazo[2,1-b]thiazole-3-acetic acid hydrazide. Their structures were elucidated by elemental analyses and spectroscopic data. All compounds were tested for antibacterial and antifungal activities. The antimicrobial activities of the compounds were assessed by the microbroth dilution technique. The compounds were also evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv (ATCC 27294); they exhibited varying degrees of inhibition in the in vitro primary screening at 6.25 μg · cm−3. The most active compound was 3-(4-nitrophenyl)-2-(((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinone.

SYNTHESIS AND ANTICONVULSANT ACTIVITY OF SOME NEW ARYLIDENEHYDRAZIDES AND 4-THIAZOLIDINONES

SummaryA number of N,N′-bis(arylidene)mono(1-methylpropyl)malonic acid dihydrazides (3a–c), 1,1-bis[[(2-aryl-4-thiazolidinone-3-yl)amino]carbonyl]-2-methylbutanes (4a–e), and 1,1-bis[[(3-alkyl/aryl-4-thiazolidinone-2-yl)hydrazono]carbonyl]-2-methylbutanes (6a–i) have been synthesized, characterized and evaluated for anticonvulsant activity. All tested compounds showed significant activity (10 to 60% protection) against pentylenetetrazole induced seizures.ZusammenfassungEine Reihe von N,N′-Bis(aryliden)mono(1-methylpropyl)malonsäure dihydraziden, (3a–c), 1,1-Bis[[2-Aryl-4-thiazolidinon-3-yl)amino]carbonyl]-2-methylbutanen (4a–e) und 1,1-Bis[[3-alkyl/aryl-4-thiazolidinon-2-yl)hydrazono]carbonyl]-2-methylbutanen (6a–i) wurden hergestellt, charakterisiert und auf ihre antikonvulsive Wirkung geprüft. Alle getesteten Substanzen zeigen relevante Aktivitäten gegen durch Pentilentetrazol induzierte Krämpfe (10–60% Schutz).

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.

SYNTHESIS AND EVALUATION OF NEW IMIDAZO[2,1-b]THIAZOLES AS ANTITUBERCULOSIS AGENTS

Tuberculosis (TB), which is caused by Mycobacterium tuberculosis, remains one of the deadliest communicable diseases for humans, and it has been identified by the World Health Organization (WHO) as one of the three priority diseases for drug research and development. In 2013, an estimated 9.0 million people developed TB and 1.5 million died from the disease, 360 000 of whom were HIV-positive (1). However, this problem has become serious as Mycobacterium tuberculosis developed resistance against both the first line as also the second line drugs. Due to this, there is emergence of multi-drug resistant (MDR) and extensively-drug resistant (XDR) strains of M. tuberculosis all over the world (2).