Patent ID: 9447053
Filing Date: 2016-09-20
CPC Classification: C07D

Claim Text:
1. A process for the preparation of a calcium complex of 10-(2,3-Dihydroxy-1-(hydroxymethyl)propyl)-1,4,7,10-tetraazacyclodecane-1,4,7-triacetic acid comprising: a) de-complexing a gadolinium complex of 10-(2,3-Dihydroxy-1-(hydroxymethyl)propyl)-1,4,7,10-tetraazacyclodecane-1,4,7-triacetic acid with a de-complexing agent to give a solution of a free ligand and a precipitated gadolinium salt, b) removing the precipitated gadolinium salt, c) binding the free ligand in the solution resulting from step b) to an acidic ion exchange resin, d) eluting the acidic ion exchange resin with an aqueous alkaline solution to give an eluate comprising the free ligand, e) treating the eluate with a second acidic ion exchange resin to acidify the eluate comprising the free ligand, and f) complexing the free ligand with Ca