Şeref Demirayak

Synthesis and anticancer and anti-HIV testing of some pyrazino[1,2-a]benzimidazole derivatives

In this study, some 1-methylene-2,3-diaryl-1,2-dihydropyrazino[1,2-a]benzimidazole and some 1-(2-arylvinyl)-3-arylpyrazino[1,2-a]benzimidazole derivatives were synthesised. The structure elucidation of the compounds was performed by IR, 1H-NMR and MASS spectroscopic data and elemental analyses results. Anticancer and anti-HIV activities of the compounds were examined, however no anti-HIV activity was seen; highly notable anticancer activity was obtained. It was also observed that the compounds were more potent against leukaemia cell lines.

In vitro antitumor activity evaluation of some 1,2,4-triazine derivatives bearing piperazine amide moiety against breast cancer cells

A series of 1,2,4-triazine derivatives bearing piperazine amide moiety has been synthesized and investigated for their potential anticancer activities. 1-[4-(5,6-Bis(4-subtituted phenyl)-1,2,4-triazin-3-yl)piperazin-1-yl]-2-[4-(3-substituted phenyl)piperazin-1-yl]ethanone derivative (1-32) compounds were synthesized by a four step synthetic procedure. The activity studies were evaluated using XTT method, BrdU method and flow cytometric analysis on MCF-7 breast cancer cells and NIH/3T3 (mouse embryonic fibroblast cells) healthy cells. Compounds 5 with 3-chlorophenyl and compound 7 with 4-chlorophenyl substitutions were found to be promising antiproliferative agents comparing with an effective anticancer drug, cisplatin.

Synthesis and antifungal activities of some aryl(benzofuran-2-yl)ketoximes

In this study, some aryl(benzofuran-2-yl)ketoximes and their ethers and esters were synthesised. The structure elucidation of the compounds was performed by IR, 1H NMR and mass spectroscopic data and elemental analyses results. Antifungal activities of the compounds were examined and notable activity was obtained.

Synthesis and Biological Evaluation of Some 1,2‐Disubstituted Benzimidazole Derivatives as New Potential Anticancer Agents

The synthesis of some new 1‐(2‐aryl‐2‐oxoethyl)‐2‐[(morpholine‐4‐yl)thioxomethyl]benzimidazole derivatives and investigation of their anticancer activities were the aims of this work. 2‐(Chloromethyl)benzimidazole compound was reacted with sulfur and morpholine via Willgerodt–Kindler reaction to give 2‐[(morpholine‐4‐yl)thioxomethyl]benzimidazole. Then, the obtained compound was reacted with appropriate α‐bromoacetophenone derivatives in the presence of potassium carbonate to give the final products. Structure elucidation of the final compounds was achieved by FT‐IR, 1H NMR spectroscopy and MS spectrometry. The anticancer activities of the final compounds were evaluated by MTT assay, BrdU method, and flow cytometric analysis on C6, MCF‐7, and A549 tumor cells. Most of the synthesized compounds exhibited considerable selectivity against the MCF‐7 and C6 cell lines.

Synthesis and initial biological evaluation of substituted 1-phenylamino-2-thio-4,5-dimethyl-1H-imidazole derivatives

In this work, some new 2-[(4,5-dimethyl-1-(arylamino)-1H-imidazol-2-yl)thio]-1-(aryl)ethanone derivatives were synthesized and investigated for their antibacterial, antifungal and anticancer activities. Toxicity of the most effective compounds was established by performing Brine-Shrimp lethality assay. Antifungal activity of the compounds was found to be higher than antibacterial and anticancer activities of the compounds.

Synthesis of 2-[4,5-dimethyl-1-(phenylamino)-1H-imidazol-2-ylthio]-N-(thiazole-2-yl)acetamide derivatives and their anticancer activities

In this work, 2-(4,5-dimethyl-1-(phenylamino)-1H-imidazol-2-ylthio)-N-(thiazol-2-yl) acetamide derivatives were synthesized by reacting 4,5-dimethyl-1-(phenylamino)-1H-imidazole-2(3H)-thione derivatives with some 2-chloro-N-(thiazol-2-yl)acetamide compounds. The structure of synthesized compounds was confirmed by IR, 1H NMR, and mass spectra. Anticancer activities of the compounds selected by the National Cancer Institute were investigated by testing against a panel of 60 different human tumor cell lines derived from nine neoplastic cancer types. Compounds 7, 13, and 23 exhibited reasonable anticancer activity against the screened cancer types with relatively low GI50 values. The compounds showed high activity against melanoma-type cell lines.

Synthesis and antimicrobial activities of some new nitroimidazole derivatives

In this study, some new nitroimidazole derivatives were obtained from 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethylamine dihydrochloride (4) and 1-(2-bromoethyl)-2-methyl-5-nitroimidazole (5), which were prepared using metronidazole. Compound 4 was reacted with arylisothiocyanates (6) to obtain 1-[2-(2-methyl-5-nitroimidazol-1-yl)ethyl]-3-arylthioureas (7) and the latter with α-bromoacetophenones (8) to give 3-[2-(2-methyl-5-nitroimidazol-1-yl)ethyl]-2-arylimino-4-aryl-4-thiazolines (9). Also 1-[2-(2-methyl-5-nitroimidazol-1-yl)ethyl]-2-phenyl-4-arylideneimida-zolin-5-ones (11) were prepared by reaction of 4 with 2-phenyl-4-arylidene-5-oxazolones (10). The reaction of the other starting material 5 with 5-arylidenethiazolidin-2,4-dione (12) gave 3-[2-(2-methyl-5-nitroimidazol-1-yl)ethyl]-5-arylidenethiazolidin-2,4-dione (13) derivatives. Structural elucidation of the compounds was performed by IR,1H-NMR and MASS spectroscopic data and elemental analysis results. Antimicrobial activities of the compounds were examined and moderate activity was obtained.

Synthesis and antitumor activity evaluation of new 2-(4-aminophenyl)benzothiazole derivatives bearing different heterocyclic rings

Abstract Twenty-five new N-[4-(benzothiazole-2-yl)phenyl]acetamide derivatives bearing different heterocyclic ring systems were synthesized using 2-(4-aminophenyl)benzothiazole structure as a pharmacophoric group. Final compounds were screened for their potential antitumor activity in vitro against approximately 60 human tumor cell lines derived from nine neoplastic diseases at National Cancer Institute, USA. 2-(4-Aminophenyl)benzothiazole structure was prepared by the reaction of 4-aminobenzoic acid and 2-aminothiophenol in polyphosphoric acid using microwave irradiation. After acetylation reaction, amide compounds 2a and 2b were obtained, which were then reacted with 2-mercapto(benz)imidazole/benzothiazole/benzoxazole derivatives in acetone with the presence of potassium carbonate to gain final compounds (3–27). Among all tested compounds, compound 10, namely N-[4-(benzothiazole-2-yl)-3-chlorophenyl]-2-[(benzimidazole-2-yl)thio]acetamide, and compound 16, namely N-[4-(benzothiazole-2-yl)phenyl]-2-[(1,5-diphenyl-1H-imidazole-2-yl)thio]acetamide, were found to be of considerable anticancer activity against some cancer cell lines.

Synthesis and anticancer activity of some 1,2,3-trisubstituted pyrazinobenzimidazole derivatives

Abstract The synthesis of some new pyrazino[1,2-a]benzimidazole derivatives and investigation of their anticancer activities were aimed in this work. Thus, 2-acetylbenzimidazole was reacted with appropriate α-bromoacetophenones and potassium carbonate in acetone to give 2-(2-acetyl-1H-benzimidazol-1-yl)-1-phenylethanone derivatives (3a–d). These diketone compounds were reacted with varied benzylamines in acetic acid to obtain 2-benzyl-1-methylidene-3-aryl-1,2-dihydropyrazino[1,2-a]benzimidazole derivatives (4a–t). The structures of the obtained compounds were elucidated by using IR, 1H-NMR, 13C-NMR, MS spectral data and elemental analyses results. Anticancer activities of the selected compounds were investigated in National Cancer Institute, Bethesda, MD. 3c and 4n showed remarkable anticancer activity comparing with standard drugs, melphalan and cisplatin.

Antimicrobial activity evaluation of new 1,3,4-oxadiazole derivatives

Infectious diseases are one of the most deadly diseases in the world1. Recently, the number of bacterial and fungal infections has rised dangereously2. Antibiotics and antifungals are the most important drug groups used in the treatment of bacterial and fungal infections. With the discovery of antibiotics, these drugs have begun to be used as main drugs in the treatment of infections. But over time, bacteria have begun to develop resistance because of frequent use and misuse. An uncontrolled increase in resistance of pathogenic microorganisms has wasted health resources3-5. This resistance to antimicrobial agents has shown ABSTRACT