US4259485A
Expired / Lapsed
US
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Crystallization process
Assignee: Eli Lilly and Co
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Filing: 1979-04-24
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Granted: 1981-03-31
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Expires: 1999-04-24
Abstract
Abstract The crystalline D-sesquisodium salt of the diacid of the formula ##STR1## and process for its preparation via acetone dilution of an aqueous solution of non-crystalline D,L-diacid and D,L-disodium salt.
Inventors
- 👤 William J. Wheeler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:58
CPC Classifications
C; C07; C07D; C07D498/00; C07D498/02; C07D498/04; C07D505/00; A; A61; A61P; A61P31/00; A61P31/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
17 words
The D-sesquisodium salt of the oxa-β-lactam diacid of the formula ##STR3## substantially free of the L form.
Claim 2
Dependent Claim
17 words
The D-sesquisodium salt of the oxa-β-lactam diacid of the formula ##STR3## substantially free of the L form.
Claim 3
Dependent Claim
9 words
The acetone solvate of the salt of claim 1.
Claim 4
Dependent Claim
71 words
The process for preparing the D-sesquisodium salt of claim 1 which comprises (1) adding acetone to a water solution containing the D,L-disodium salt of the formula ##STR4## and the D,L-diacid of the formula ##STR5## in a molar ratio of the disalt to the diacid of between about 1 to 1 to about 6 to 1, and (2) cooling the solution to a temperature between about -35° C. and about -10° C.
Claim 5
Dependent Claim
19 words
The process of claim 3 wherein the molar ratio of D,L-disodium salt to the D,L-diacid is 1:1 or 2:1.
References Cited (Backward Citations)
US4138486A
Cited
US4201782A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |