1.New metabolites of thiabendazole and the metabolism of thiabendazole by mouse embryo in vivo and in vitro.
Fujitani T1, Yoneyama M, Ogata A, Ueta T, Mori K, Ichikawa H. Food Chem Toxicol. 1991 Apr;29(4):265-74.
Thiabendazole [2-(4'-thiazolyl)benzimidazole; TBZ], a teratogen in ICR mice, is known to be mainly metabolized to 5-hydroxy-TBZ (5-OH-TBZ) and its conjugates in domestic and laboratory animals. Besides the known metabolites of TBZ, 4-hydroxy-TBZ and 2-acetylbenzimidazole (ABI) were identified as new metabolites of TBZ in the urine of F344 rats and ICR mice. 5-OH-TBZ and ABI, as well as TBZ, were found in the embryos of ICR mice given TBZ orally on day 10 of gestation. In the whole-embryo culture system, 5-OH-TBZ and ABI in the medium, and TBZ, 5-OH-TBZ and ABI in the embryo were detected after 24 hr of culture in 25 or 50 micrograms TBZ ml. However, the amount of metabolites in the embryo in vitro was very small compared with that detected in vivo, whereas the amount of TBZ was comparable. Furthermore, the mouse embryo homogenate, at organogenesis, metabolized TBZ to 5-OH-TBZ or ABI. The specific activity required by this homogenate to form 5-OH-TBZ or ABI was less than 1/1000 of that of the liver microsomal fraction.
2.Synthesis and anticancer activity of some 1,2,3-trisubstituted pyrazinobenzimidazole derivatives.
Demirayak Ş1, Yurttaş L. J Enzyme Inhib Med Chem. 2014 Dec;29(6):811-22. doi: 10.3109/14756366.2013.858142. Epub 2014 Jan 24.
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, (1)H-NMR, (13)C-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.
3.Synthesis of novel benzofuran and related benzimidazole derivatives for evaluation of in vitro anti-HIV-1, anticancer and antimicrobial activities.
Rida SM1, El-Hawash SA, Fahmy HT, Hazzaa AA, El-Meligy MM. Arch Pharm Res. 2006 Oct;29(10):826-33.
Previously, we synthesized and evaluated several benzofuran derivatives containing heterocyclic ring substituents linked to the benzofuran nucleus at C-2 by a two- to four-atom spacer as potential anti-HIV-1, anticancer and antimicrobial agents. Among these derivatives, NSC 725612 and NSC 725716 exhibited interesting anti-HIV-1 activity. To further investigate the structure-activity relationship, we synthesized several new benzofuran derivatives derived from 2-acetylbenzofuran (2, 3a-c) and 2-bromoacetylbenzofuran (6; 7a,b; 8a,b). The compounds were designed to comprise the heterocyclic substituents directly linked to the benzofuran nucleus at C-2. Moreover, various related benzimidazoles derived from 2-acetylbenzimidazole and from 2-cyanomethylbenzimidazole (12a,b; 13a,b; 15; 16a,b) were also prepared as isosteres. The synthesized compounds were preliminarily evaluated for their in vitro anti-HIV-1, anticancer and antimicrobial activity.
4.[Effect of thiabendazole (TBZ) on glutathione (GSH) and GSH related enzymes in mice liver].
Toda C1, Yasui T, Hashizume K, Nagano H. Yakugaku Zasshi. 2000 Sep;120(9):787-94.
The present study examines the effects of thiabendazole (TBZ), its metabolites, 5-hydroxythiabendazole (5-OH TBZ) and 2-acetylbenzimidazole (ABI), and structural related compounds, thiazoles and thioamides on glutathione (GSH) concentration and GSH-related enzymes in the livers of ICR 11 week-old female mice. GSH concentration in liver and kidney of mice given orally TBZ 0.65 mol/kg (TBZ group) increased significantly compared with control mice from 24 h to 48 h after administration of TBZ. Even in mice to which TBZ at 0.175 mol/kg was administered in combination with L-buthionine sulfoximine (BSO) 4 mmol/kg (i.p.) (BSO-TBZ group), kidney GSH showed significant increase compared with BSO-control mice 48 h after the administration of TBZ. gamma-Glutamylcysteine synthetase (gamma-GCS) activity in the livers of the TBZ group markedly increased at 48 h and that of BSO-TBZ group increased from 24 h to 48 h. gamma-GCS in mice liver is thus enhanced by TBZ regardless of BSO administration.