<chemical> 1-(2-(4-(1-(4-methoxyphenyl)-2-nitro-2-phenylethenyl)phenoxy)ethyl)pyrrolidine. A non-steroidal oestrogen antagonist (as the 1:1 citrate) most commonly used as a research tool in animal studies. ... Pharmacological action: oestrogen antagonists. ... Chemical name: Pyrrolidine, 1-(2-(4-(1-(4-methoxyphenyl)-2-nitro-2-phenylethenyl)ph...