The condensation of 4-aminophenol (I) with 2-chloro-3-nitropyridine (II) in DMF at 100 C gives 4-(3-nitropyridin-2-ylamino)phenol (III), which is reduced with H2 over Pd/C in THF-methanol to afford 4-(3-aminopyridin-2-ylamino)phenol (IV). Finally, this compound is condensed with 4-methoxybenzenesulfonylchloride (V) by means of pyridine in THF.