zindoxifene zindoxifene zindoxifene (inn; former developmental code names d-16726, nsc-341952) is a nonsteroidal selective estrogen receptor modulator (serm) that was under development in the 1980s and early 1990s for the treatment of breast cancer but was not marketed. it showed estrogenic-like activity in preclinical studies and failed to demonstrate effectiveness as a treatment for breast cancer in clinical trials. zindoxifene was the lead compound of the distinct 2-phenylindole class of serms, and the marketed serm bazedoxifene was derived from the major active metabolite of zindoxifene, d-15414. zindoxifene was first described in 1984. zindoxifeneclinical dataother namesd-16726; nsc-341952identifiers iupac name acetate cas number86111-26-4pubchem cid65645chemspider59082unii1irs95m8dnkeggc14745chebichebi:35052chemblchembl32227comptox dashboard (epa)dtxsid60235396 chemical and physical dataformulac21h21no4molar mass351.402 g·mol−13d model (jsmol)interactive image smiles ccn1c2=c(c=c(c=c2)oc(=o)c)c(=c1c3=cc=c(c=c3)oc(=o)c)c inchi inchi=1s/c21h21no4/c1-5-22-20-11-10-18(26-15(4)24)12-19(20)13(2)21(22)16-6-8-17(9-7-16)25-14(3)23/h6-12h,5h2,1-4h3key:kszgvnzsujhoja-uhfffaoysa-n