5,5'-(1,8-Dioxooctane-1,8-diyldiimino)bis[2,4,6-triiodo-3-(methylcarbamoyl)benzoic acid]

3-[7-[[3-carboxy-2,4,6-triiodo-5-(methylcarbamoyl)phenyl]carbamoyl]heptanoylamino]-2,4,6-triiodo-5-(methylcarbamoyl)benzoic acid