d-15414 d-15414 d-15414 is a nonsteroidal weak estrogen of the 2-phenylindole group which was never marketed. it is the major metabolite of the selective estrogen receptor modulator (serm) zindoxifene (d-16726). d-15414 has high affinity for the estrogen receptor (er) and inhibits the growth of er-positive mcf-7 breast cancer cells in vitro. however, contradictorily, subsequent research found that the drug produced fully estrogenic effects in vitro similarly to but less actively than estradiol, with no antiestrogenic activity observed. the reason for the discrepancy between the findings is unclear, though may be due to methodology. the unexpected estrogenic activity of d-15414 may be responsible for the failure of zindoxifene in clinical trials as a treatment for breast cancer. d-15414identifiers iupac name 1-ethyl-2-(4-hydroxyphenyl)-3-methylindol-5-ol cas number86111-11-7 ypubchem cid128800chemspider114137unii58ae9z8tw6chemblchembl287232comptox dashboard (epa)dtxsid801006609 chemical and physical dataformulac17h17no2molar mass267.328 g·mol−13d model (jsmol)interactive image smiles ccn1c2=c(c=c(c=c2)o)c(=c1c3=cc=c(c=c3)o)c inchi inchi=1s/c17h17no2/c1-3-18-16-9-8-14(20)10-15(16)11(2)17(18)12-4-6-13(19)7-5-12/h4-10,19-20h,3h2,1-2h3key:bxtnoiwytwipel-uhfffaoysa-n