COMPOSITIONS CONTAINING COMPLEXES OF METALS OF SERIES OF LANTHANIDES Russian patent published in 2019 - IPC C07D257/02 A61K49/10 A61K9/00 A61K9/08 B01D15/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a purification method for removal of impurities of metal ions from a complex of a metal of a series of lanthanides, which consists of a metal of a series of lanthanides with a macrocyclic chelator from a class of aminocarboxylic acids. Method includes the following steps: (i) complexing said chelator containing said metal impurity M with an excess of said lanthanide series metal in a suitable solvent to form a first solution of said lanthanide series metal complex containing excess lanthanide and M ions; (ii) removing excess lanthanide and M ions from the first solution from step (i) by bringing said solution one or more times into contact with the absorption resin in form of a pharmaceutically acceptable cationic organic salt, wherein excess lanthanide and M are bound to complexes on said resin; (iii) separating the solid-phase resin from the first solution from step (ii) to obtain a second solution which contains said lanthanide series metal complex free of excess lanthanide and M. M is a metal ion selected from calcium, magnesium and zinc or mixtures thereof. Said second solution contains less than 10 ppm M. Invention also discloses a method of producing a liquid pharmaceutical composition, a method of producing a contrast agent for MRI, an absorption resin and use thereof.

EFFECT: disclosed invention enables to obtain a liquid pharmaceutical composition with low level of metal ion impurities.

18 cl, 2 dwg, 3 tbl, 9 ex