US5122614A
Expired / Lapsed
US
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Active carbonates of polyalkylene oxides for modification of polypeptides
Assignee: Viskase Holdings Inc
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Filing: 1990-04-19
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Granted: 1992-06-16
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Expires: 2010-04-19
Abstract
Abstract Poly(ethylene glycol)-N-succinimide carbonate and its preparation are disclosed. Polyethylene glycol (PEG) is converted into its N-succinimide carbonate derivative. This form of the polymer reacts readily with amino groups of proteins in aqueous buffers. The modified proteins have PEG-chains grafted onto the polypeptide backbone by means of stable, hydrolysis-resistant urethane (carbamate) linkages.
Inventors
- 👤 Shmuel Zalipsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:05
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/46; A; A61; A61K; A61K47/00; A61K47/50; A61K47/51; A61K47/56; A61K47/59; A61K47/60
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
A compound having the structure: ##STR8## wherein R 1 is H--, H 3 C--, or an oxycarbonyl-N-dicarboximide group; wherein each R 2 , R 3 , and R 4 is an alkyl group which may be straight or branched, and wherein each R 2 , R 3 , and R 4 may be independently the same as, or different from, the others of R 2 , R 3 , and R 4 ; wherein R 5 is an N-dicarboximide group; and wherein a is an integer between 1 and 1000 and each of b and c is an integer between 0 and 1000, and the sum of a, b, and c is between 10 and 1000.
Claim 2
Dependent Claim
116 words
A compound having the structure: ##STR8## wherein R 1 is H--, H 3 C--, or an oxycarbonyl-N-dicarboximide group; wherein each R 2 , R 3 , and R 4 is an alkyl group which may be straight or branched, and wherein each R 2 , R 3 , and R 4 may be independently the same as, or different from, the others of R 2 , R 3 , and R 4 ; wherein R 5 is an N-dicarboximide group; and wherein a is an integer between 1 and 1000 and each of b and c is an integer between 0 and 1000, and the sum of a, b, and c is between 10 and 1000.
Claim 3
Dependent Claim
37 words
A compound of claim 1, wherein each of R 2 , R 3 , R 4 is CH 2 CH 2 , CH 2 CHCH 3 , or CH 2 CH 2 CH 2 CH 2 .
Claim 4
Dependent Claim
43 words
A compound according to claim 1 wherein each of R 1 and R 2 is an N-dicarboximide group selected from the group consisting of N-succinimide, N-phthalimide, N-glutarimide, N-tetrahydrophthalimide and N-norbornene-2,3-dicarboximide and where R 1 and R 5 may be the same or different.
Claim 5
Dependent Claim
13 words
A compound according to claim 3 wherein R 5 is an N-succinimide group.
Claim 6
Dependent Claim
27 words
A compound of claim 1 having the structure: ##STR9## where R 1 is H 3 C--, or H--; and a is an integer between 10 and 1000.
Claim 7
Dependent Claim
18 words
A compound of claim 1 having the structure ##STR10## wherein a is an integer between 10 and 1000.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-16 | 1995-12-16 | 1996-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-16 | 1999-12-16 | 2000-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-16 | 2003-12-16 | 2004-06-16 | $7700.00 | Window Closed / Lapsed |