2-Acetylpyridine thiosemicarbazones: Cytotoxic activity in nanomolar doses against malignant gliomas

2-Acetylpyridine N(4)-phenyl thiosemicarbazone (H2Ac4Ph), and its N(4)-ortho-tolyl (H2Ac4oT), N(4)meta-tolyl (H2Ac4mT), N(4)-para-toly1 (H2Ac4pT), N(4)-ortho-chlorophenyl (H2Ac4oClPh), N(4)-meta-chlorophenyl (H2Ac4mClPh) and N(4)-para-chlorophenyl (H2Ac4pClPh) derivatives were assayed for their cytotoxicity against RT2 (expressing p53 protein) and against T98 (expressing mutant p53 protein) glioma cells. The compounds were highly cytotoxic against RT2 (IC50=24-1.4 nM) and T98 cells (IC50=50-1.0 nM). 1050 for cisplatin = 5 (RT2) and 17 mu M (T98). The thiosemicarbazones presented haemolytic activity with IC50>10(-3)M, indicating a very good therapeutic index. SAR studies suggested that stereo properties are critical to define the potential activity of the studied compounds against the RT2 cell line, while electronic properties seem to be important for interaction with the biological target in 198 cells. (C) 2010 Elsevier Masson SAS. All rights reserved.