US4981955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Depolymerization method of heparin
Assignee: Individual
•
Filing: 1990-02-26
•
Granted: 1991-01-01
•
Expires: 2010-02-26
Abstract
Abstract A method of depolymerizing heparin to obtain a heparin with low molecular weight provided with antithrombotic activity comprises treating a quarternary ammonium salt of heparin with a quarternary ammonium hydroxide.
Inventors
- 👤 Lorenzo L. Lopez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:23
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0075; C08B37/0078
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
89 words
A method of depolymerizing heparin to obtain a heparin having a low molecular weight provided with antithrombotic activity comprising contacting a fully salified quaternary ammonium salt of heparin with a quaternary ammonium hydroxide in a non-aqueous polar solvent for a time sufficient to degrade the heparin into a low molecular weight product provided with long duration antithrombotic activity, contacting the degraded heparin with a sodium, calcium or magnesium salt and thereafter isolating the low molecular weight heparin in the form of the resulting sodium, calcium or magnesium salt thereof.
Claim 2
Independent Claim
89 words
A method of depolymerizing heparin to obtain a heparin having a low molecular weight provided with antithrombotic activity comprising contacting a fully salified quaternary ammonium salt of heparin with a quaternary ammonium hydroxide in a non-aqueous polar solvent for a time sufficient to degrade the heparin into a low molecular weight product provided with long duration antithrombotic activity, contacting the degraded heparin with a sodium, calcium or magnesium salt and thereafter isolating the low molecular weight heparin in the form of the resulting sodium, calcium or magnesium salt thereof.
Claim 3
Dependent Claim
22 words
A method of depolymerizing heparin according to claim 1 wherein the contacting is effected at a temperature between 10° and 60° C.
Claim 4
Dependent Claim
36 words
A method of depolymerizing heparin according to claim 2 in which the contacting is continued until the low molecular weight heparin product resulting from the depolymerization has an average molecular weight between 2500 and 6000 daltons.
Claim 5
Dependent Claim
25 words
A method of depolymerizing heparin according to claim 3 in which the sodium, calcium or magnesium salt of heparin is contacted with a reducing agent.
Claim 6
Dependent Claim
17 words
A method of depolymerizing heparin according to claim 4 in which the reducing agent is sodium borohydride.
Claim 7
Dependent Claim
25 words
A method of depolymerizing heparin according to claim 2 in which the sodium, calcium or magnesium salt of heparin is contacted with a reducing agent.
Claim 8
Dependent Claim
17 words
A method of depolymerizing heparin according to claim 6 in which the reducing agent is sodium borohydride.
Claim 9
Dependent Claim
36 words
A method of depolymerizing heparin according to claim 1 in which the contacting is continued until the low molecular weight heparin product resulting from the depolymerization has an average molecular weight between 2500 and 6000 daltons.
Claim 10
Dependent Claim
25 words
A method of depolymerizing heparin according to claim 8 in which the sodium, calcium or magnesium salt of heparin is contacted with a reducing agent.
Claim 11
Dependent Claim
17 words
A method of depolymerizing heparin according to claim 9 in which the reducing agent is sodium borohydride.
Claim 12
Dependent Claim
20 words
A method of depolymerizing heparin according to claim 1 in which the quaternary ammonium salt of heparin is benzetonium heparinate.
Claim 13
Dependent Claim
17 words
A method of depolymerizing heparin according to claim 11 in which the ammonium hydroxide is benzyltrimethylammonium hydroxide.
Claim 14
Dependent Claim
22 words
A method of depolymerizing heparin according to claim 12 wherein the contacting is effected at a temperature between 10° and 60° C.
Claim 15
Dependent Claim
36 words
A method of depolymerizing heparin according to claim 13 in which the contacting is continued until the low molecular weight heparin product resulting from the depolymerization has an average molecular weight between 2500 and 6000 daltons.
Claim 16
Dependent Claim
25 words
A method of depolymerizing heparin according to claim 14 in which the sodium, calcium or magnesium salt is of heparin contacted with a reducing agent.
Claim 17
Dependent Claim
17 words
A method of depolymerizing heparin according to claim 15 in which the reducing agent is sodium borohydride.
Claim 18
Dependent Claim
17 words
The method of depolymerizing heparin according to claim 1 in which the ammonium hydroxide is benzyltrimethylammonium hydroxide.
Claim 19
Dependent Claim
15 words
The method of depolymerizing heparin according to claim 17 in which the solvent is dichloromethane.
Claim 20
Dependent Claim
15 words
The method of depolymerizing heparin according to claim 1 in which the solvent is dichloromethane.
References Cited (Backward Citations)
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