Synthesis of phenol-class azo derivatives of 4-aminosalicylic acid

To explore the better prodrug of 4-aminosalicylic acid（4-ASA）with higher activity and less side effects against the inflammatory bowel disease.4-ASA,after a succession of synthesis process,was conjugated with various carder molecules to get seven azo derivatives of 4-ASA.All compounds were characterized by FT-IR,;H NMR,;C NMR spectras in detail.New derivatives of 4-ASA were definituded.