Patent US4105668A successfully refreshed from Google Patents.
US4105668A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for 6-amino-2,2-dimethyl-3-(5-tetrazolyl)penam
Assignee: Pfizer Inc
•
Filing: 1977-04-22
•
Granted: 1978-08-08
•
Expires: 1997-04-22
Abstract
Abstract Certain 6-amino-2,2-dimethyl-3-(1-substituted tetrazol-5-yl)penam and 6-(protected amino)-2,2-dimethyl-3-(1-substituted tetrazolyl-5-yl)penam compounds react with hydrogen fluoride to produce 6-amino-2,2-dimethyl-3-(5-tetrazolyl)penam, a useful intermediate for the synthesis of antibacterial agents.
Inventors
- 👤 Susumu Nakanishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:45
CPC Classifications
C; C07; C07D; C07D499/00; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
243 words
A process for the preparation of 6-amino-2,2-dimethyl-3-(5-tetrazolyl)penam, or an acid-addition salt thereof, which comprises reacting a compound of formula ##STR16## or an acid-addition salt thereof, with hydrogen fluoride, at a temperature within the range from about -20° C. to about 20° C; wherein R 1 is selected from the group consisting of hydrogen and ##STR17## wherein R 3 , R 4 , and R 5 are each selected from the group consisting of hydrogen, fluoro, chloro, bromo, alkyl having from one to four carbon atoms, alkoxy having from one to four carbon atoms and phenyl; and R 2 is selected from the group consisting of ##STR18## wherein R 7 is at the 3-, 4- or 5-position and it is selected from the group consisting of hydrogen, hydroxy, fluoro, chloro, bromo, iodo, alkyl having from one to six carbon atoms, alkoxy having from one to six carbon atoms, benzyloxy and phenyl; R 8 is selected from the group consisting of hydrogen, hydroxy, fluoro, chloro, unbranched-alkyl having from one to six carbon atoms and unbranched-alkoxy having from one to six carbon atoms; R 10 is selected from the group consisting of hydrogen and methyl; and X is selected from the group consisting of oxygen and sulfur; provided that at least one of R 7 and R 8 is selected from the group consisting of 2-hydroxy, 4-hydroxy, 4-alkoxy having from one to six carbon atoms, 2-(unbranched-alkoxy) having from one to six carbon atoms and 4-benzyloxy .
Claim 2
Dependent Claim
243 words
A process for the preparation of 6-amino-2,2-dimethyl-3-(5-tetrazolyl)penam, or an acid-addition salt thereof, which comprises reacting a compound of formula ##STR16## or an acid-addition salt thereof, with hydrogen fluoride, at a temperature within the range from about -20° C. to about 20° C; wherein R 1 is selected from the group consisting of hydrogen and ##STR17## wherein R 3 , R 4 , and R 5 are each selected from the group consisting of hydrogen, fluoro, chloro, bromo, alkyl having from one to four carbon atoms, alkoxy having from one to four carbon atoms and phenyl; and R 2 is selected from the group consisting of ##STR18## wherein R 7 is at the 3-, 4- or 5-position and it is selected from the group consisting of hydrogen, hydroxy, fluoro, chloro, bromo, iodo, alkyl having from one to six carbon atoms, alkoxy having from one to six carbon atoms, benzyloxy and phenyl; R 8 is selected from the group consisting of hydrogen, hydroxy, fluoro, chloro, unbranched-alkyl having from one to six carbon atoms and unbranched-alkoxy having from one to six carbon atoms; R 10 is selected from the group consisting of hydrogen and methyl; and X is selected from the group consisting of oxygen and sulfur; provided that at least one of R 7 and R 8 is selected from the group consisting of 2-hydroxy, 4-hydroxy, 4-alkoxy having from one to six carbon atoms, 2-(unbranched-alkoxy) having from one to six carbon atoms and 4-benzyloxy .
Claim 3
Dependent Claim
18 words
The process according to claim 1, wherein at least about twenty molar equivalents of hydrogen fluoride are used.
Claim 4
Dependent Claim
21 words
The process according to claim 2, wherein the said temperature is in the range from about -5° C. to 5° C.
Claim 5
Dependent Claim
11 words
The process according to claim 3, wherein R 1 is triphenylmethyl.
Claim 6
Dependent Claim
11 words
The process according to claim 3, wherein R 1 is hydrogen.
Claim 7
Dependent Claim
11 words
The process according to claim 5, wherein R 2 is furfuryl.
Claim 8
Dependent Claim
11 words
The process according to claim 5, wherein R 2 is ##STR19##
Claim 9
Dependent Claim
23 words
The process according to claim 7, wherein R 7 is hydrogen and R 8 is 4-alkoxy having from one to six carbon atoms.
Claim 10
Dependent Claim
11 words
The process according to claim 8, wherein R 8 is 4-methoxy.
Claim 11
Dependent Claim
23 words
The process according to claim 1 wherein the action is carried out in the presence of at least one molar equivalent of anisole.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-07 | 1982-02-06 | 1982-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-07 | 1986-02-06 | 1986-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-07 | 1990-02-06 | 1990-08-08 | $7700.00 | Window Closed / Lapsed |