RU 16117, an orally active estriol-like weak estrogen.

RU 16117, the 11 alpha-methoxy derivative of ethynyl estradiol, is an orally active weak estrogen potentially effective in the treatment of estrogen-deficiency in postmenopausal women (climacteric symptoms and severe osteoporosis). Biochemical studies have shown that RU 16117, like estriol, possesses the properties characteristic of a partial estrogen agonist/antagonist. RU 16117 binds to the cytosol estrogen receptor (ER) to form a complex which dissociates much faster than the estradiol complex.