7-[[(9H-Fluoren-9-ylmethoxy)carbonyl]amino]-4-hydroxy-3-[2-(4-methoxyphenyl)diazenyl]-2-naphthalenesulfonic Acid is an intermediate in synthesizing 7-[[4-[Bis(3-Amino-3-oxopropyl)amino]-6-chloro-1,3,5-triazin-2-yl]amino]-4-hydroxy-3-[(4-methoxyphenyl)azo]-2-naphthalenesulfonic Acid (B426265), which acts as a non-peptide hormone receptor antagonist affecting physiological homeostasis and reproduction. Hormone antagonist.