estradiol 3-propionate estradiol 3-propionate estradiol 3-propionate, or 3-propanoylestradiol, also known as estra-1,3,5(10)-triene-3,17β-diol 3-propionate, is a semisynthetic, steroidal estrogen that was never marketed. it is an estrogen ester, specifically, a propionic acid ester of estradiol, and acts as a prodrug to it in vivo. the chemical structure of estradiol 3-propionate is contained within estradiol dipropionate, estrapronicate, and orestrate, all of which are also estradiol esters. not to be confused with estradiol 17β-propionate. estradiol 3-propionateclinical dataother namesestradiol 3-propanoate; 3-propanoylestradiol; 3,17β-hydroxyestra-1,3,5(10)-trien-3-yl propionateroutes ofadministrationintramuscular injection, vaginaldrug classestrogen; estrogen esteratc codenoneidentifiers iupac name phenanthren-3-yl] propanoate cas number1323-33-7 ychemspider2298529uniids9ws297bvcomptox dashboard (epa)dtxsid60927623 chemical and physical dataformulac21h28o3molar mass328.452 g·mol−13d model (jsmol)interactive image smiles ccc(=o)oc1ccc2c(c1)cc32cc4(3cc4o)c inchi inchi=inchi=1s/c21h28o3/c1-3-20(23)24-14-5-7-15-13(12-14)4-6-17-16(15)10-11-21(2)18(17)8-9-19(21)22/h5,7,12,16-19,22h,3-4,6,8-11h2,1-2h3/t16-,17-,18+,19?,21?/m1/s1key:inchikey=fonfxfzwmzjfcd-nykhlbabsa-n