Estradiol stearate
Estradiol stearate (brand name Depofollan), or estradiol octadecanoate, is a naturally occurring steroidal estrogen and an estrogen ester – specifically, the C17β stearate ester of estradiol. It occurs in the body as a very long-lasting metabolite and prohormone of estradiol. In addition, estradiol stearate is or has been available as a pharmaceutical drug for use via depot intramuscular injection. The drug was introduced in 1941 as Depofollan and was the first long-acting estrogen, although it has never been widely used. It has been reported in at least one source to have a duration of at least one month.
Estradiol monopropionate
Estradiol monopropionate (brand names Acrofollin, Agofollin, Akrofollin, Di-Ovahormon Depot, Follhormon, Ovocylin), also known as estradiol 17β-propionate or estradiol 17β-propanoate, as well as estra-1,3,5(10)-trien-3,17β-diol 17β-propionate, is a synthetic, steroidal estrogen and an estrogen ester – specifically, the C17β propionate ester of estradiol – which was first marketed in the late 1930s or early 1940s.