panomifene panomifene panomifene (inn; developmental codes gyki 13504 and egis 5650) is a nonsteroidal selective estrogen receptor modulator (serm) of the triphenylethylene group related to tamoxifen that was under development as an antineoplastic agent by egis pharmaceuticals and ivax drug research institute in the 1990s for the treatment of breast cancer, but it was never marketed. it reached phase ii clinical trials before development was terminated. the drug was described in 1981. panomifeneclinical dataother namesgyki-13504; egis-5650identifiers iupac name 2-phenoxy]ethylamino]ethanol cas number77599-17-8pubchem cid3033654chemspider2298282uniigcw5e728occhemblchembl2105273chemical and physical dataformulac25h24f3no2molar mass427.467 g·mol−13d model (jsmol)interactive image smiles c1=cc=c(c=c1)/c(=c(/c2=cc=cc=c2)\c(f)(f)f)/c3=cc=c(c=c3)occncco inchi inchi=1s/c25h24f3no2/c26-25(27,28)24(21-9-5-2-6-10-21)23(19-7-3-1-4-8-19)20-11-13-22(14-12-20)31-18-16-29-15-17-30/h1-14,29-30h,15-18h2/b24-23+key:mhxvdxxarzcvrk-wcwdxbqesa-n