EP0296740A2
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EP
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Hyaluronic acid derivatives and their production
Assignee: Skandigen AB
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Filing: 1988-06-10
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Granted: —
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Expires: 2008-06-10
Abstract
Abstract Conjugates of hyaluronic acid with a physiologically active or chemotherapeutic substance, e.g. an antibiotic, covalently bound thereto, have valuable delayed release properties. They may be made by the coupling of hyaluronic acid with the said substance in the presence of a suitable coupling agent, e.g. cyanogen bromide.
Inventors
- 👤 Derek Clifford C/O Fermentech Limited Ellwood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 09:00
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0063; C08B37/0072; A; A61; A61K; A61K47/00; A61K47/50; A61K47/51; A61K47/56; A61K47/61
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
25 words
A conjugate of hyaluronic acid (in the form of a free acid or a salt) with a physiologically active or chemotherapeutic substance covalently bound thereto.
Claim 2
Dependent Claim
25 words
A conjugate of hyaluronic acid (in the form of a free acid or a salt) with a physiologically active or chemotherapeutic substance covalently bound thereto.
Claim 3
Dependent Claim
32 words
A hyaluronic acid conjugate according to claim 1 in which the physiologically active or chemotherapeutic substance contains a free primary amino group through which it is covalently bound to the hyaluronic acid.
Claim 4
Dependent Claim
24 words
A hyaluronic acid conjugate according to claim 2 in which the physiologically active or chemotherapeutic substance is an antibiotic which contains an amino group.
Claim 5
Dependent Claim
16 words
A hyaluronic acid conjugate according to claim 3 in which the said antibiotic is a penicillin.
Claim 6
Dependent Claim
33 words
A hyaluronic acid conjugate according to any one of claims 1 to 4 in which the physiologically active or chemotherapeutic substance makes up from 1 to 50% of the weight of the conjugate.
Claim 7
Dependent Claim
71 words
Process for the preparation of a hyaluronic acid conjugate as claimed in any one of claims 1 to 5 which comprises reacting hyaluronic acid (as the free acid or the salt) and the said physiologically active or chemotherapeutic substance with a coupling agent which is capable of reacting with one or more hydroxyls or carboxyls present in the hyaluronic acid and one or more functional groups present in the said substance.
Claim 8
Dependent Claim
21 words
Process according to claim 6 in which the said coupling agent is cyanogen bromide, a water soluble carbodiimide, N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, or 2-ethyl-5-phenyl-isoxuzolium-3′-sulfonate.
Claim 9
Dependent Claim
49 words
Process according to claim 6 in which the hyaluronic acid is reacted in an aqueous alkaline medium with cyanogen bromide, the pH of the reaction mixture is adjusted to near neutrality with an acid, and a physiologically active or chemotherapeutic substance containing a primary amino group is then added.
Claim 10
Dependent Claim
17 words
Process according to claim 8 in which the said substance is an antibiotic containing an amino group.
Claim 11
Dependent Claim
54 words
Process according to claim 8 or 9 in which 0.5 to 2 parts by weight of cyanogen bromide are used for each part by weight of hyaluronic acid, and 5 to 20 parts by weight of the amino-group-containing substance are then added for each 100 parts by weight of the hyaluronic acid initially used.
References Cited (Backward Citations)
No citation records indexed.
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