m2613 m2613 m2613 is a nonsteroidal estrogen derived from triphenylbromoethylene which was studied in the treatment of breast cancer in women in the 1940s but was never marketed. m2613clinical dataother namesm-2613; methoxyethoxy-triphenylbromoethylenedrug classnonsteroidal estrogenidentifiers iupac name 1-bromo-2-(p-ethoxyphenyl)-2-(p-methoxyphenyl)-1-phenylethylene cas number114795-29-8chemical and physical dataformulac23h21bro2molar mass409.323 g·mol−1