Antimony(III) complexes with 2-benzoylpyridine-derived thiosemicarbazones: Cytotoxicity against human leukemia cell lines

The antimony(III) complexes [Sb(2Bz4DH)Cl-2) (1), [Sb(H2Bz4M)Cl-3]center dot 2H(2)O (2) and [Sb(2Bz4Ph)Cl-2] (3) were obtained with 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N(4)-methyl (H2Bz4M) and N(4)-phenyl (H2Bz4Ph) derivatives. H2Bz4DH. H2Bz4Ph and complexes (1-3) exhibited high cytotoxic activity against HL-60 and Jurkat human leukemia cell lines. When these compounds were tested against HL-60 cells with ectopic expression of BcrAbl, Bcl-2 or Bcl-XL, which confer resistance to apoptosis against a variety of death-inducing agents, the cytotoxicity was much lower, indicating apoptosis to be part of their mechanism of action. The cytotoxic activity of complexes 2 and 3 against HL-60 and Jurkat cells was significantly higher than that of the corresponding thiosemicarbazones, suggesting coordination to be an interesting strategy of cytotoxic dose reduction. (C) 2010 Elsevier Masson SAS. All rights reserved.