synthesized by condensation of the natural or synthetic isatins with hydrazine and were evaluated for their in vitro and in vivoantitumor activities. More than half of the obtained compounds showed potent cytotoxicity according to the MTT assay on five different human cancer cell lines (i.e. HeLa, SGC-7901, HepG2, U251, and A549), with compound 3b 3,3′-(hydrazine-1,2-diylidene)bis (5-methylindolin-2-one)