Estrogen receptor (ER) antagonists are valuable in the treatment of ER-positive human breast cancer. In this study, we designed and synthesized nine new derivatives of 17β- estradiol (E2) with a bulky side chain attached to its C-7α position, and determined their ER antagonistic activity using in vitro bioassays. Four of the derivatives showed a strong inhibition of ERα transactivation activity in a luciferase reporter assay and blocked ERα ...
[Jackson, P. Mark; Moody, Christopher J.; Shah, Pritom Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1990 , # 11 p. 2909 - 2918]