Résumé : Triphenyltin 3,5-di-isopropylsalicylate, compound 1, is characterized by a maximum tolerated dose (MTD) of 20 mg/kg. Bis[di-n-butyl(2-pyrrolidone-5-carboxylato)tin] oxide, compound 2, and (di-n-butyltin bis(3-amino-4-methyl-benzoate), compound 3, exhibit similar acute toxicities (MTD = 8 mg/kg) despite their lower in vitro activity, as compared to compound 1, against the two human tumor cell lines MCF-7 and WiDr. All three are inactive in vivo against L1210 leukemia in mice.