US3855202A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One step process for the production of a monoester of macrolide antibiotics
Assignee: Meiji Seika Kaisha Ltd
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Filing: 1972-06-15
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Granted: 1974-12-17
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Expires: 1992-06-15
Abstract
Abstract A mono-ester of the antibiotic SF-837 substance and leucomycin A3 in which the hydroxyl group at the 10-position of the lactone ring of the molecule has been esterified can simply and effeciently be produced in one step by reacting the free base form of the SF-837 substance or leucomycin A3 with an acyl halide in solution in a selected solvent and in the presence of a selected acid-binding agent, in contrast to the previously known method of producing said mono-ester which needs two-stage reactions, namely the preparation of the di-ester and subsequent partial de-acylation of the di-ester.
Inventors
- 👤 S Omoto
- 👤 S Inoue
- 👤 T Niida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:08
CPC Classifications
C; C07; C07H; C07H17/00; C07H17/04; C07H17/08
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
15 words
A PROCESS FOR THE PRODUCTION OF A MONO-ESTER OF THE SF-837 SUBSTANCE OF THE FORMULA:
Claim 2
Dependent Claim
15 words
A PROCESS FOR THE PRODUCTION OF A MONO-ESTER OF THE SF-837 SUBSTANCE OF THE FORMULA:
Claim 3
Dependent Claim
58 words
A process as claimed in claim 1 in which the mono-acetate of the SF-837 substance is produced by reacting the SF-837 substance with acetyl chloride or bromide in solution in a solvent selected from benzene, toluene, ethyl acetate and methyl isobutyl ketone and in the presence of a quantity of an acid-binding agent selected from pyridine and picoline.
Claim 4
Dependent Claim
58 words
A process as claimed in claim 1 in which the mono-propionate of the SF-837 substance is produced by reacting the SF-837 substance with propionyl chloride or bromide in solution in a solvent selected from benzene, toluene, ethyl acetate and methyl isobutyl ketone and in the presence of a quantity of an acid-binding agent selected from pyridine and picoline.
Claim 5
Dependent Claim
26 words
A process as claimed in claim 1 in which the reaction of the SF-837 substance is carried out at a temperature of 0* to 30* C.
Claim 6
Dependent Claim
36 words
A process as claimed in claim 1 in which pyridine or picoline as the acid-binding agent is present in such an amount which is substantially sufficient to neutralize all the hydrogen halide liberated during the reaction.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |