METHOD FOR OBTAINING NADROPARIN CALCIUM Russian patent published in 2021 - IPC C08B37/10 A61K31/727 

FIELD: pharmaceutical industry.

SUBSTANCE: invention relates to a technology for producing calcium nadroparin and can be used for the production of drugs based on it. The preparation method includes dissolving sodium heparin in water and adding sodium nitrite, the resulting reaction mass is stirred for 60-90 minutes, the pH is adjusted to 10, then sodium borohydride and ethyl alcohol are added to the solution, stirred until the oil precipitates, the solution is decanted, the remaining oil is stirred in ethyl alcohol, the precipitate is filtered off and dried. Then re-precipitation of sodium nadroparin is carried out, to which water is poured, a strongly acidic cation exchanger in calcium form is added, and kept for 2 hours. The resulting solution is filtered, the resin is washed with water and dried to obtain nadroparin calcium. Next, the obtained nadroparin calcium is dissolved in water and ethyl alcohol is added at a temperature of 20°C. The reaction mass is centrifuged, after the solution is decanted from the precipitated oil, which is evaporated to the formation of a powder, which is additionally dried in a vacuum drying oven at a temperature of 30°C for 72 hours, obtaining calcium nadroparin of the required fraction.

EFFECT: present method ensures obtaining nadroparin sodium with the maximum number of fractions required for the synthesis of nadroparin calcium. The method reduces the low molecular weight fractions contained in the intermediate product and makes it possible to get the necessary fraction of nadroparin calcium in high yield.

1 cl, 1 dwg, 4 ex