Synthesis and in vitro cytotoxicity of novel 1,4-disubstituted phthalazines

Eight novel 1,4-disubstituted phthalazines (7–14) were designed and synthesized. The structures of all the synthesized compounds were confirmed by IR, 1H NMR, 13C NMR, MS and elemental analysis. Their in vitro cytotoxicity against cancer cell lines (Bel-7402 and HT-1080) were evaluated by standard MTT assay. Among them, compounds 9 and 11 exhibited more potent cytotoxicity than cisplatin.