Patent US1984868A successfully refreshed from Google Patents.
EP0347588A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Heparin derivatives and process for their preparation
Assignee: Alfa Wasserman SpA
•
Filing: 1989-05-19
•
Granted: —
•
Expires: 2009-05-19
Abstract
Abstract New heparin derivatives having antithrombotic activity, also endowed with reduced hemorrhagic and anticoagulant effects, obtained by treating in a basic medium heparins of various origin, optionally in the presence of alkali metal salts and of a reducing agent. The heparin derivatives obtained through this treatment show peculiar chemico-physical characteristics, like new signals at about 53 and 54 p.p.m. in the 13 C-NMR spectrum and a raise of the specific rotatory power, compared to that of the starting heparins, to values between + 50 to +90°. Said structural modifications produce an improvement of the biological properties of the heparin, substantially keeping the antithrombotic activity while diminishing the hemorrhagic effect in vivo and the anticoagulant activity in vitro.
Inventors
- 👤 Silvano Piani
- 👤 Gianfranco Tamagnone
- 👤 Raul Roberto Alpino
- 👤 Maria Rita Milani
- 👤 Marinella Fantuz
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 10:19
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0075; A; A61; A61P; A61P7/00; A61P7/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
49 words
1) New heparin derivatives characterized by signals in the 13 C-NMR spectrum at about 53 and about 54 ppm, specific rotatory power between about +50 and about +90° in aqueous solution, sulfur content between about 8% and about 11 % and sulfates/carboxyls ratio between about 1.50 and about 2.20.
Claim 2
Dependent Claim
49 words
1) New heparin derivatives characterized by signals in the 13 C-NMR spectrum at about 53 and about 54 ppm, specific rotatory power between about +50 and about +90° in aqueous solution, sulfur content between about 8% and about 11 % and sulfates/carboxyls ratio between about 1.50 and about 2.20.
Claim 3
Dependent Claim
187 words
2) Process for the preparation of new heparinic derivatives characterized by signals in the 13 C-NMR spectrum at about 53 and about 54 ppm, specific rotatory power between about +50° and about +90° in aqueous solution, sulfur content between about 8% and about 11 % and sulfates/carboxyls ratio between about 1.50 and about 2.20, which comprises treating an aqueous solution of a heparinic material with a base of an alkali or alkali-earth metal at a concentration between about 0.01 N and about 1 N, in the presence of a concentration between 0 and about 1 N of a salt of an alkali or an alkali-earth metal, facultatively in the presence of a catalytic amount of a reducing agent, for a period of time between 0.5 and 24 hours at a temperature between about 35 °C and about 70 C, optionally purifying the reaction mixture by percolation thru a ionic exchange resin or by dialysis, and precipitating the compounds having the so modified structure by adding from about 2 to about 4 volumes of an alcohol containing from 1 to 3 carbon atoms at a pH about neutral.
Claim 4
Dependent Claim
187 words
2) Process for the preparation of new heparinic derivatives characterized by signals in the 13 C-NMR spectrum at about 53 and about 54 ppm, specific rotatory power between about +50° and about +90° in aqueous solution, sulfur content between about 8% and about 11 % and sulfates/carboxyls ratio between about 1.50 and about 2.20, which comprises treating an aqueous solution of a heparinic material with a base of an alkali or alkali-earth metal at a concentration between about 0.01 N and about 1 N, in the presence of a concentration between 0 and about 1 N of a salt of an alkali or an alkali-earth metal, facultatively in the presence of a catalytic amount of a reducing agent, for a period of time between 0.5 and 24 hours at a temperature between about 35 °C and about 70 C, optionally purifying the reaction mixture by percolation thru a ionic exchange resin or by dialysis, and precipitating the compounds having the so modified structure by adding from about 2 to about 4 volumes of an alcohol containing from 1 to 3 carbon atoms at a pH about neutral.
Claim 5
Dependent Claim
17 words
3) Process according to claim 2 wherein the base is selected among sodium, potassium and barium hydroxides.
Claim 6
Dependent Claim
29 words
4) Process according to claim 2 wherein the salts are selected among the sodium, potassium, barium, calcium and magnesium chlorides and acetates and the sodium, potassium and magnesium sulfates.
Claim 7
Dependent Claim
14 words
5) Process according to claim 2 wherein the reducing agent is the sodium borohydride.
Claim 8
Dependent Claim
19 words
6) Process according to claim 2 wherein the compounds are precipitated by adding about 2.5 volumes of ethyl alcohol.
Claim 9
Dependent Claim
18 words
7) Use of the compounds of claim 1 for the preparation of pharmaceutical formulations for treating thrombotic pathologies.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.