1,3-Benzenedicarboxamide, 5-(acetyl(2,3-dihydroxypropyl)amino)-N,N'-bis(2-hydroxyethyl)-2,4,6-triiodo- 5-(N-(2,3-Dihydroxypropyl)acetamido)-N,N'-bis(2-hydroxyethyl)-2,4,6-triiodoisophthalamide 74411-74-8