Synthesis, Characterization, and in vitro Cytotoxicity of Organotin Derivatives of 4-Biphenylcarboxylic Acid

The di- and tri-organotin derivatives of 4-biphenylcarboxylic acid, {[(CH3CH2CH2CH2)2Sn(OCOC6H4C6H5)]2O}2 (1) and R3SnOCOC6H4C6H5 (R = C6H5, 2; c-C6H11, 3; C6H5C(CH3)2CH2, 4), have been synthesized and characterized by elemental analysis, IR, 1H, and 13C NMR spectroscopies. The crystal structures of 1 and 2 have been determined. Compound 1 is a centrosymmetric dimmer with two distinct types of carboxylate moieties and tin atoms with distorted trigonal bipyramidal geometries and 2 possesses a distorted tetrahedral structure. The in vitro cytotoxicity of 4 against three human tumor cell lines was found to be higher than that for cis-platin used clinically.