11β-Nitrate Estrane Analogues: Potent Estrogens

Article abstract of DOI:10.1021/jm00130a014

Various estrane derivatives 1 reacted with cerium ammonium nitrate (CAN) selectively and efficiently to provide 9α,11β-difunctionalized derivatives 2, which were subsequently deoxygenated at C-9 with triethylsilane/boron trifluoride etherate to the desired target 11β-nitratoestranes 3a, 3b, and 5.When examined for estrogenic and postcoital antifertility activity, 11β-nitrates 2c, 2d, and 3b most notably displayed more potent oral activity than did ethynylestradiol.