METHOD FOR SELECTIVE CRYSTALLISATION OF Z-ISOMER OF IOPROMIDE Russian patent published in 2013 - IPC C07C231/02 C07C231/24 C07C233/69 C07C235/68 

FIELD: chemistry.

SUBSTANCE: disclosed is a method for selective crystallisation of the Z-isomer of an iodine-containing radiocontrast agent - iopromide of formula (1), involving a) dissolving crude iopromide or iopromide concentrate which contains E and Z forms of isomers in an alcohol; and b) heating the obtained alcohol solution at 100-150°C to obtain a crystalline Z-isomer of iopromide. Also disclosed is a method of producing a composition which contains a Z-isomer of iopromide of formula (1), involving i) selective crystallisation of the Z-isomer of iopromide according to claim 1 from crude iopromide which contains a mixture of E- and Z-isomers of iopromide or iopromide concentrate to obtain a crystalline Z-isomer of iopromide; and ii) dissolving the obtained crystalline Z-isomer of iopromide together with a pharmaceutically acceptable excipient.

EFFECT: enabling production of iopromide with high content of the Z-isomer.

15 cl, 7 ex, 2 tbl, 2 dwg