Methanol → N,N'-bis-[2,3-dihydroxypropyl]-5-[3-hydroxy-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide

Participants

Reaction Steps

N,N'-Bis-[2,3-diacetyloxypropyl]-5-[3-acetyloxy-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide of example 5b (4.20 g, 4.20 mmol) was treated with a 0.105M solution of methanolic sodium methoxide [prepared by the addition of Na metal (48 mg, 2.10 mmol) to dry methanol (20 ml)] under a nitrogen atmosphere for 2.5 hours. The pH was then adjusted to 6.70 using Dowex-50 resin (H+ form) and AG-1 (OH- form) as necessary. The resin was removed and the solvents evaporated to give a yellow oil. This product was dissolved in 20 ml of deionized water and the pH adjusted to 6.98 by the addition of AG-1 (OH- 1 form) resin. The resin was filtered off and the filtrate containing the crude product was purified by low pressure reverse phase column chromatography using a CHP-20 resin to obtain N,N'-bis-[2,3-dihydroxypropyl]-5-[3-hydroxy-2-oxo-1-pyrrolidinyl]-2,4,6-triiodo-1,3-benzenedicarboxamide as a white foam (2.36 g, 71% yield).

Provenance & Evidence