Production of oligosaccharide fractions having antithrombotic properties by controlled chemical depolymerization of heparin
US5084564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 1989 |
| Grant date | Jan 28, 1992 |
| Priority date | — |
| Expiry date | Apr 10, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08B37/0078
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The process makes an oligosaccharide fraction from commerically available heparin solutions containing from 1 to 10 % heparin. This oligosaccharide fraction has antithrombotic activity, bioavailability, almost no toxic effects as well as a comparatively lower hemorrhagic risk and a reduction in bleeding time and a molecular weight range of less than 5000 D. This process includes the steps of ultrafiltering an aqueous starting solution of the heparin through a membrane of 3,000 D nominal molecular weight cut-off to form a rejected ultrafiltered heparin solution so that the oligosaccharide fraction does not contain molecular fragments too short for binding with antithrombin and thrombin; performing a phase partitioning of the rejected ultrafiltered heparin solution with aqueous saline solution and dichloromethane and making a heparin-quaternary ammonium complex so as to form a dichloromethane phase and a saline phase so that fractions of a predetermined anionicity and specificity are excluded from the product, adding benzyl chloride to the dichloromethane phase to benzylate and after that adding benzyltrimethylammonium hydroxide to the dichloromethane phase to form a depolymerized he…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.