Abstract Twenty new samples of hydrazone functionalized thioparabanic acid and rhodanine analogues were prepared by reacting a mixture of acyl methylene substituted rhodanine and hydantoin compounds with hydrazine and acyl hydrazine derivatives in good yields (53–89%). The cytotoxic effect of newly synthesized compounds 3a–g, 4a–m was evaluated on the human colon cancer cell line (DLD-1) and human