Synthesis and biological evaluation of estrone 3-O-ether derivatives containing the piperazine moiety.

A series of new estrone derivatives were designed and synthesized, and their structures were confirmed by spectroscopic methods. All new estrone derivatives were investigated for their in vitro cytotoxic efficacies against a panel of three human prostate cancer cell lines (PC-3, LNCaP, and DU145). The derivatives 6, 7, 10, 15, 16, 20, 21, 22, 24 and 26 showed important cytotoxic actions against individual carcinoma cell line collections. Moreover, antagonistic activities of compounds (7, 15, 16 and 21) towards a1-ARs (α1A, α1B, and α1D) were further evaluated using dual-luciferase reporter assays, and the compounds 16 and 21 exhibited better a1-ARs subtype selectivity. The structure-activity relationship (SAR) suggested that the substitute's type and position on the phenyl group leads to the interesting variations within pharmacological effects of resultant molecular systems.