Synthesis and Antitumor Activity of 1-Phenyl-4-substituted Phthalazine Derivatives

In order to find more efficient and economical antitumor drugs, a series of 1-phenyl-4-substituted phthalazine derivatives were synthesized and evaluated for antiproliferative activity in vivo. The structures of the synthesized compounds were confirmed by H-1 NMR, C-13 NMR and HRMS. The antitumor activity of the target compounds was performed against four cancer cell lines by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT). The results showed that some compounds had a good antitumor activity, especially, N-(4-methoxyphenyl)-2-((4-phenylphthalazin-1-yl)thio)acetamide (5f) and N-(3-chloro-4-fluorophenyl)-2-(4-(4-phenylphthalazin-1-yl)piperazin-1-yl)acetamide (8c), exhibited better antitumor activities with IC50 values of 8.13 and 9.31 mu mol.L-1 against the human esophageal cancer cells, which were superior to 5-fuorouracil.