miproxifene miproxifene miproxifene (inn) (former developmental code name dp-tat-59) is a nonsteroidal selective estrogen receptor modulator (serm) of the triphenylethylene group that was never marketed. it is a derivative of afimoxifene (4-hydroxytamoxifen) in which an additional 4-isopropyl group is present in the β-phenyl ring. the drug has been found to be 3- to 10-fold more potent than tamoxifen in inhibiting breast cancer cell growth in in vitro models. miproxifene is the active metabolite of miproxifene phosphate (tat-59), a phosphate ester and prodrug of miproxifene that was developed to improve its water solubility. miproxifene phosphate was under development for the treatment of breast cancer and reached phase iii clinical trials for this indication but development was discontinued. miproxifeneclinical dataother namesdp-tat-59identifiers iupac name 4-phenyl]-2-(4-propan-2-ylphenyl)but-1-enyl]phenol cas number129612-87-9pubchem cid3037015chemspider2300875uniibgj4z7930wchemblchembl2074961chemical and physical dataformulac29h35no2molar mass429.604 g·mol−13d model (jsmol)interactive image smiles cc/c(=c(\c1=cc=c(c=c1)o)/c2=cc=c(c=c2)occn(c)c)/c3=cc=c(c=c3)c(c)c inchi inchi=1s/c29h35no2/c1-6-28(23-9-7-22(8-10-23)21(2)3)29(24-11-15-26(31)16-12-24)25-13-17-27(18-14-25)32-20-19-30(4)5/h7-18,21,31h,6,19-20h2,1-5h3/b29-28-key:fvvpwvfwoomxez-ziadkaodsa-n