ABSTRACT
The design, synthesis, and in vitro antiproliferative activity of a novel series of sulfide (4a-i) and sulfoxide (5a-h) derivatives of benzimidazole, in which different aromatic and heteroaromatic acetamides are linked to benzimidazole via sulfide (4a-i) and sulfoxide (5a-h) linker, are reported and the structure-activity relationship is discussed. The new derivatives were prepared by coupling 2-(mercaptomethyl)benzimidazole with 2-bromo-N-(substituted) acetamides in dry acetone in the presence of anhydrous potassium carbonate. With very few exceptions, all of the synthesized compounds showed varying antiprolific activities against HepG2, MCF-7, and A549 cell lines. Compound 5a was very similar in potency to doxorubicin as an anticancer drug, with IC50 values 4.1 ± 0.5, 4.1 ± 0.5, and 5.0 ± 0.6 µg/mL versus 4.2 ± 0.5, 4.9 ± 0.6, and 6.1 ± 0.6 µg/mL against HepG2, MCF-7, and A549 cell lines, respectively. In contrast, none of the compounds showed activity against human prostate PC3 cancer cells. Additionally, the sulfoxide derivatives were more potent than the corresponding sulfides.
ABSTRACT
New series of pyrazolo[3,4-d]pyrimidines (7a-e and 13a-d) and pyrazole hydrazones 17a-d were synthesized and evaluated for their antiproliferative activity against human breast adenocarcinoma MCF-7 cell line. Most of the tested compounds exploited potent to moderate growth inhibitory activity, in particular compound 7e exhibited superior potency to the reference drug cisplatin (IC(50)=7.60 and 13.29 µM, respectively). The antitumor activity of the new compounds was accompanied by significant increase in the activity of superoxide dismutase with concomitant decrease in the activities of catalase and glutathione peroxidase and reduced glutathione level. Accordingly, the overproduction of hydrogen peroxide, nitric oxide and other free radicals allowed reactive oxygen species (ROS)-mediated tumor cells death, as monitored by reduction in the synthesis of protein and nucleic acids.