CA3058886C — Method for manufacturing diastereomer of citric acid derivative
Assigned to Otsuka Pharmaceutical Factory Inc · Expires 2021-11-09 · 5y expired
What this patent protects
By performing ion exchange column chromatography on an aqueous solution containing a compound A represented by formula (A) and citric acid or by treating the aqueous solution with calcium carbonate, the citric acid in the aqueous solution is removed, and a crystalline compound A …
USPTO Abstract
By performing ion exchange column chromatography on an aqueous solution containing a compound A represented by formula (A) and citric acid or by treating the aqueous solution with calcium carbonate, the citric acid in the aqueous solution is removed, and a crystalline compound A is obtained by subsequently subjecting the aqueous solution to several steps. In addition, a high-purity, non-crystalline compound A is obtained by treating the aqueous solution containing the compound A and the citric acid with calcium carbonate, sulfuric acid, an organic solvent, etc. to remove the citric acid and the crystalline compound A in the solution. The three-dimensional structure of the crystalline compound A is an SS stereoisomer according to the R-S system. The three-dimensional structure of the non-crystalline compound A is an SR stereoisomer according to the R-S system.
Drugs covered by this patent
- Elucirem (GADOPICLENOL) · Guerbet
Bibliographic data sourced from FDA Orange Book + USPTO public records. Plain-English summary generated by AI grounded in source text. Patent term extensions (PTR, SPC, pediatric) may shift the effective expiry. Not legal advice.
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