METHOD FOR PRODUCING CALCOBUTROL Russian patent published in 2022 - IPC C07D257/02 A61K49/06 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for producing highly pure calcobutrol using highly pure butrol, wherein the method includes the following: the first stage of reaction of cyclen (1,4,7,10-tetraazacyclododecane) with 4,4-dimethyl-3,5,8-trioxabicyclo[5,1,0]octane, resulting in 3-(1,4,7,10-tetraazacyclododecane-1-yl)butane-1,2,4-triol further subjected to a reaction with a haloacetic acid, resulting in crude butrol; the second stage of primary purification of the crude butrol using ion exchange resin; and the third stage of secondary purification of the primary purified butrol by crystallisation; wherein the second stage is conducted using simultaneously anion exchange resin and cation exchange resin; wherein the anion exchange resin is selected from the group consisting of quaternary ammonium, tertiary ammonium, tertiary amine, secondary amine, and primary amine, and the cation exchange resin is selected from the group consisting of a sulphonic acid group and a carboxyl group; wherein the third stage is conducted using an aqueous methanol solution with a water content of at least 20% as a solvent for crystallisation, then through a reaction of butrol produced by stage 1 with calcium carbonate at room temperature.

EFFECT: possibility of effectively synthesising butrol with a 99% purity or more through the purification of crude butrol using ion exchange resin and crystallisation, and producing highly pure calcobutrol using highly pure butrol at room temperature.

4 cl, 9 dwg, 3 ex