Synthesis, Uterotrophic, and Antiuterotrophic Activities of Some Estradiol Derivatives Containing Thiadiazole, Thiazoline, and Thiazolidinone Moieties

The effect of structural modification on the biological activity of hormones has been studied on five novel series of estradiol analogs bearing a variety of substituents at the 2‐position of the steroidal nucleus. The synthesized compounds include 2‐[2‐(5‐substituted amino‐1,3,4‐thiadiazol‐2‐yl)vinyl]estradiol 17ß‐acetate 5–9 , 2‐aroylmethylestradiols 10–12 , 2‐[2‐aryl‐2‐(substituted thiocarbamoylhydrazono)ethyl]estradiols 13–18 and their cyclic thiazoline 19–24 , and thiazolidinone derivatives 25–30 . Among the products, the p ‐hydroxybenzoylmethylestradiol 12 exhibited the highest antiestrogenic activity of 63%. It also elicited 34% of the uterotrophic activity of estradiol.