Amide derivatives of 9,11-seco-estra-1,3,5(10)-trien-11-oic acid as modified orally active estrogen agonists with moderate antagonistic activity

Some alkyl and aromatic amine derivatives of 9,11-seco-estra-1,3,5(10)-trien-11-oic acid have been synthesized with an aim to prepare orally active estrogen antagonists. Compounds 7 an n-propyl amide, 8 an n-butyl amide, and 16 a p-anisidyl amide of C-seco-estrane showed significant estrogen antagonistic activity (>20%), while, the majority of compounds possessed high estrogen agonistic activity on oral administration at 10 mg/kg dose in rats.