The enantiomeric [1,2-bis(2-hydroxyphenyl)-ethylenediamine]dichloroplatinum(II) complexes were synthesized and their configuration assessed. A preliminary test in the cisplatin-resistant human NIH:OVCAR-3 ovarian cancer cell line, which was previously characterized by its sensitivity against several therapeutically used drugs, showed that both enantiomers produce cytocidal effects in a concentration of 2.5 microM. A difference between the enantiomers became evident from the faster onset of cytocidal activity of the S,S-configurated compound.