A series of benzothiazole bearing piperazino-arylsulfonamides (5a-k), and arylthiol analogues (6a-j) as well as substituted benzothiazoles having sulfonamides (9b, 9l-n and 10) have been synthesized. All compounds were evaluated, in vitro, for their antiproliferative activity against a large panel of human tumor-derived cell lines. Compounds 5c, 5d, 5j, 6b, 6c and 6j were the most potent analogues in this series, showing activity against both cell lines derived from haematological and solid tumors (CC50 range = 8-24 μM), only 5d was found to be selective and not cytotoxic to normal human tissues
