estradiol undecylenate estradiol undecylenate estradiol undecylenate (eue; developmental code name sh-368) is an estrogen medication and estrogen ester which was never marketed. it is the c17β undecenoate (undecylenate) ester of estradiol. following an intramuscular injection, eue has a very prolonged effect, exceeding that of other estradiol esters like estradiol valerate and estradiol enanthate. due to its very long duration of action, eue releases only subthreshold amounts of estradiol at conventional doses. however, this may still be useful in menopausal hormone therapy. not to be confused with estradiol undecylate. estradiol undecylenateclinical dataother namessh-368; estradiol undecenoate; estra-1,3,5(10)-triene-3,17β-diol 17β-(10-undecenoate)routes ofadministrationintramuscular injectiondrug classestrogen; estrogen esteridentifiers iupac name phenanthren-17-yl] undec-10-enoate cas number85702-61-0pubchem cid56842583chemspider21165111comptox dashboard (epa)dtxsid90234993 echa infocard100.080.203 chemical and physical dataformulac29h42o3molar mass438.652 g·mol−13d model (jsmol)interactive image smiles c12cc3(1cc2oc(=o)ccccccccc=c)ccc4=c3c=cc(=c4)o inchi inchi=1s/c29h42o3/c1-3-4-5-6-7-8-9-10-11-28(31)32-27-17-16-26-25-14-12-21-20-22(30)13-15-23(21)24(25)18-19-29(26,27)2/h3,13,15,20,24-27,30h,1,4-12,14,16-19h2,2h3/t24-,25-,26+,27+,29+/m1/s1key:vjtiehbtpqorml-gvgnizhqsa-n