Dichloro[1,2-bis(4-hydroxyphenyl)ethylenediamine]platinum(II) complexes: an approach to develop compounds with a specific effect on the hormone-dependent mammary carcinoma

Stereoisomeric dichloro [1,2-bis(4-hydroxyphenyl)ethylenediamine]platinum(II) complexes (meso-3a, (+/-)-3b, (+)-3c, (-)-3d) and their N,N'-dibutyl derivatives (meso-4a, (+/-)-4b, (+)-4c, (-)-4d) were synthesized and tested on antitumor activity. The most active compound, 3d, shows a modest inhibition of the [3H]estradiol receptor interaction and causes a marked effect on the growth of the hormone-dependent human MCF 7 breast cancer cell line. It is also active on the hormone-independent human MDA-MB 231 breast cancer cell line, on the ADJ/PC6 plasmacytoma of the Balb/C mouse, and on the L 5222 leukemia of the BD IX rat. Apparently the inhibition of the MCF 7 cell line is not mediated by the estrogen receptor system. Histopathological studies on 3d revealed very low toxicity.