Patent ID: 7687249
Filing Date: 2010-03-30
Classification: A61P,C08B,Y10S

Abstract:
1. A process for the preparation of a glycosaminoglycan-sulphate having a ratio between factor Xa and factor IIa inhibition activities equal to or higher than 1.0, having a reduced hemorragic risk, and prepared from an E. coli K5 polysaccharide, the process consisting essentially of the following steps: (a) N-deacetylating and N-sulphating said (b) enzymatically epimerizing and depolymerizing the N-deacetylated and N-sulphated polysaccharide, wherein said epimerizing comprises epimerizing with a glucuronyl C5-epimerase enzyme; (c) partially O-sulphating with a sulphating agent and partially O-desulphating the epimerized and depolymerized polysaccharide; (d) partially 6O-sulphating the polysaccharide obtained from step (c) with a sulphating agent; and (e) N-resulphating the 6O-sulphated polysaccharide, thereby providing the glycosaminoglycan-sulphate, wherein in step (c), the partial O-sulphating is performed for a time equal to or less than 6 hours and the molar ratio between the sulphating agent and the epimerized and depolymerized polysaccharide E. coli K5 polysaccharide is equal to or less than 2.5; and wherein in step (d), the partial 6O-sulphating is performed for a time equal to or less than 2 hours and the molar ratio between the sulphating agent and the hydroxyl groups of the polysaccharide obtained from step (c) is less than or equal to 1.5.