4-(((Acetyl(4-methoxyphenyl)amino)acetyl)(4-methoxyphenyl)amino)butanoic acid 71455-76-0 Butanoic acid, 4-(((acetyl(4-methoxyphenyl)amino)acetyl)(4-methoxyphenyl)amino)- N-(N-Acetyl-2-(p-anisidino)acetyl)-4-(p-anisidino)butyric acid