Synthesis of 2′′,2′′′-[6′-(4-sulfamoylphenylamino)-1′,3′,5′-triazine-2′,4′-diyl]-bis(azanediyl)diacetic acid 3. Reagents and conditions: 4-(4′,6′-dichloro-1′,3′,5′-triazin-2′-ylamino)-benzene-sulfonamide 1, glycine, NaOH, and H2O were refluxed for 24 h. Product yield: 65%.