147646-62-6 2,7-Naphthalenedisulfonic acid, 4,4'-((1,8-dioxo-1,8-octanediyl)diimino)bis(5-hydroxy- 4,4'-(1,6-Hexanediylbis(carbonylamino))bis(5-hydroxy-2,7-naphthalenedisulfonic acid) 4,4'-Hca-bis(napss)