Iothalamate meglumine

Conray,Mallinckrodt Inc.,US,1962

Diagnostic aid (radiopaque medium).

ChEBI: Iothalamate meglumine is an amidobenzoic acid.

Crude 5-amino-2,4,6-triiodo-N-methylisophthalamic acid (21.0 g) was dissolved in warm dimethylacetamide (40 ml) and acetic anhydride (30 ml) and concentrated sulfuric acid (2 drops) were added. This solution was heated on the steam bath for 2 hours, then heated at 110°C for 5 minutes, then cooled. Water and ammonium hydroxide were added to destroy the excess acetic anhydride, after which the mixture was evaporated to a volume of 50 ml. The cooled solution was acidified with concentrated hydrochloric acid and a tan solid was collected. The crude product was dissolved in 100 ml of water containing a slight excess of sodium hydroxide. The pH was adjusted to 4.5 with acetic acid, and the solution was treated with charcoal. The colorless solution was acidified with concentrated hydrochloric acid and cooled, and the precipitate was filtered off and dried under reduced pressure. The resulting 5- acetamido-2,4,6-triiodo-N-methylisophthalamic acid decomposes about 285°C and does not melt below 300°C.
5-acetamido-2,4,6-triiodo-N-methylisophthalamic acid was slurried in water and dissolved by the addition of an equivalent quantity of N-methylglucamine. The solution was evaporated to dryness to yield the meglumate salt of 5- acetamido-2,4,6-triiodo-N-methylisophthalamic acid.

Conray(Mallinckrodt).

Diagnostic aid (radiopaque medium)

Iothalamate meglumineis a high-osmolar, ionic monomer with 47% boundiodine content. Conray is indicated for use in angiography,excretory urography, arthrography, cholangiography, endoscopicretrograde cholangiopancreatography, and variousCT procedures.