nitromifene nitromifene nitromifene (inn; also as the citrate salt nitromifene citrate (usan), developmental code names ci-628, cn-5518, cn-55945) is a nonsteroidal selective estrogen receptor modulator (serm) related to triphenylethylenes like tamoxifen that was never marketed. it is a mixture of (e)- and (z)-isomers that possess similar antiestrogenic activity. the drug was described in 1966. along with tamoxifen, nafoxidine, and clomifene, it was one of the earliest serms. nitromifeneclinical dataother namesci-628; cn-5518; cn-55945identifiers iupac name 1-phenoxy]ethyl]pyrrolidine cas number10448-84-7 5863-35-4 (citrate)pubchem cid22150chemspider20796unii5fs1nj6q8ncomptox dashboard (epa)dtxsid50883143 chemical and physical dataformulac27h28n2o4molar mass444.531 g·mol−13d model (jsmol)interactive image smiles coc1=cc=c(c=c1)c(=c(c2=cc=cc=c2)(=o))c3=cc=c(c=c3)occn4cccc4 inchi inchi=1s/c27h28n2o4/c1-32-24-13-9-21(10-14-24)26(27(29(30)31)23-7-3-2-4-8-23)22-11-15-25(16-12-22)33-20-19-28-17-5-6-18-28/h2-4,7-16h,5-6,17-20h2,1h3key:mfkmxufmhoczhp-uhfffaoysa-n nitromifene has been found to dissociate from the estrogen receptor 250-fold faster than estradiol. this may be involved in its antagonistic activity at the estrogen receptor.