Abstract
Eight pyrazole-1-carbothioamide nucleosides were synthesized through conensation of 3-(4-aminophenyl)-pyrazole-1-carbothioamide derivative 2 with four aldoses (arabinose, mannose, glucose and galactose) and acetylation of the produced nucleosides 3a-d with acetic anhydride in pyridine at room temperature to give their corresponding acetyl derivatives 4a-d. Their chemical structures were confirmed by spectroscopic and elemental analysis. The antiproliferative activity was screened against various human cancer cell lines (MCF-7, HepG2 and HCT-116) in vitro; compound 4b showed a significant IC50 values (8.5±0.72 for MCF-7, 9.4±0.84 for HepG2 and 11.7±0.89 µg/ml for HCT-116) which were close to the reference drug 5-fluorouracil (5-FU). Molecular docking study was utilized to illustrate the ability of the more active compounds 3b and 4b to inhibit thymidylate synthase and compare the results with an antimetabolite drug used in cancer chemotherapy "Raltitrexed".