Patent US4515972A successfully refreshed from Google Patents.
US4515972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intermediates and method for producing intermediates useful in the preparation of 7-oxabicycloheptane prostaglandin derivatives
Assignee: ER Squibb and Sons LLC
•
Filing: 1983-10-19
•
Granted: 1985-05-07
•
Expires: 2003-10-19
Abstract
Abstract A method is provided for preparing intermediates for use in preparing 7-oxabicycloheptane prostaglandin derivatives which method includes the steps of reducing (exo)hexa hydro-4,5-epoxyisobenzofuran-1,3-dione to the corresponding diol, subjecting the diol to a chloroformylation reaction to form a compound of the structure ##STR1## reacting the above with pyridine to form the cyclic carbonate reacting the cyclic carbonate with an alkanol to form the alcohol of the strucure ##STR2## tosylating the above alcohol to form the tosylate and subjecting the above tosylate to a cyanation reaction to form the cyano carbonate of the structure ##STR3## The cyano carbonate may then be reduced by, for example, reaction with diisobutyl aluminum hydride to form the hemiacetal ##STR4## which is used in preparing 7-oxabicycloheptane prostaglandin derivatives as disclosed in U.S. Pat. No. 4,143,054. New intermediates of the structures set out above, other than the hemiacetal, are also provided.
Inventors
- 👤 Jagabandhu Das
- 👤 Martin F. Haslanger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:19
CPC Classifications
C; C07; C07D; C07D493/00; C07D493/02; C07D493/08; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
124 words
A method for preparing a hemiacetal of the structure ##STR30## which comprises reducing a dione (mesoanhydride) of the structure ##STR31## to form a diol of the structure ##STR32## chloroformylating the diol by reacting same with phosgene to form the alcohol of the structure ##STR33## reacting the alcohol with pyridine to form the cyclic carbonate of the structure ##STR34## reacting the cyclic carbonate with an alkanol to form an alcohol of the structure ##STR35## reacting the alcohol with a protecting compound containing a sulfonyl group to form the protected alcohol of the structure ##STR36## wherein "Protecting group" contains a sulfonyl moiety, reacting the protected alcohol with a cyanide to form the cyanocarbonate of the structure ##STR37## and reducing the cyano carbonate to form the hemiacetal.
Claim 2
Independent Claim
124 words
A method for preparing a hemiacetal of the structure ##STR30## which comprises reducing a dione (mesoanhydride) of the structure ##STR31## to form a diol of the structure ##STR32## chloroformylating the diol by reacting same with phosgene to form the alcohol of the structure ##STR33## reacting the alcohol with pyridine to form the cyclic carbonate of the structure ##STR34## reacting the cyclic carbonate with an alkanol to form an alcohol of the structure ##STR35## reacting the alcohol with a protecting compound containing a sulfonyl group to form the protected alcohol of the structure ##STR36## wherein "Protecting group" contains a sulfonyl moiety, reacting the protected alcohol with a cyanide to form the cyanocarbonate of the structure ##STR37## and reducing the cyano carbonate to form the hemiacetal.
Claim 3
Dependent Claim
23 words
The method as defined in claim 1 wherein the mesoanhydride is reduced by reacting same with lithium aluminum hydride, diisobutylaluminum hydride or diborane.
Claim 4
Dependent Claim
15 words
The method as defined in claim 1 wherein said alkanol contains 1 to 12 carbons.
Claim 5
Dependent Claim
12 words
The method as defined in claim 3 wherein said alkanol is isopropanol.
Claim 6
Dependent Claim
17 words
The method as defined in claim 1 wherein said protecting group is tosyl, mesyl or trifluoromethane sulfonyl.
Claim 7
Dependent Claim
15 words
The method as defined in claim 1 wherein said cyanide is an alkali metal cycanide.
Claim 8
Dependent Claim
18 words
The method as defined in claim 6 wherein said alkali metal cyanide is sodium cyanide or potassium cyanide.
Claim 9
Dependent Claim
22 words
The method as defined in claim 1 wherein the cyanocarbonate is reduced by reaction with diisobutyl aluminum hydride to form the hemiacetal.
Claim 10
Dependent Claim
52 words
An intermediate for use in preparing 7-oxabicycloheptane prostaglandin derivatives, said intermediate having the structure ##STR38## wherein A is ##STR39## OH, O-Protecting group, or CN and B is OH where A is ##STR40## and B is ##STR41## wherein A is OH, O-Protecting group or CN and wherein "Protecting group" contains a sulfonyl moiety.
Claim 11
Dependent Claim
52 words
An intermediate for use in preparing 7-oxabicycloheptane prostaglandin derivatives, said intermediate having the structure ##STR38## wherein A is ##STR39## OH, O-Protecting group, or CN and B is OH where A is ##STR40## and B is ##STR41## wherein A is OH, O-Protecting group or CN and wherein "Protecting group" contains a sulfonyl moiety.
Claim 12
Dependent Claim
11 words
The intermediate as defined in claim 9 having the structure ##STR42##
Claim 13
Dependent Claim
11 words
The intermediate as defined in claim 9 having the structure ##STR43##
Claim 14
Dependent Claim
11 words
The intermediate as defined in claim 11 where alkyl is isopropyl.
Claim 15
Dependent Claim
18 words
The intermediate as defined in claim 9 having the structure ##STR44## wherein "Protecting group" contains a sulfonyl moiety.
Claim 16
Dependent Claim
15 words
The intermediate as defined in claim 13 wherein the protecting group is tosyl or mesyl.
Claim 17
Dependent Claim
11 words
The intermediate as defined in claim 9 having the structure ##STR45##
Claim 18
Dependent Claim
11 words
The intermediate as defined in claim 15 wherein alkyl is isopropyl.
Claim 19
Dependent Claim
15 words
An intermediate for use in preparing 7-oxabicycloheptane prostaglandin derivatives, said intermediate having the structure ##STR46##
Claim 20
Dependent Claim
15 words
An intermediate for use in preparing 7-oxabicycloheptane prostaglandin derivatives, said intermediate having the structure ##STR46##
References Cited (Backward Citations)
US4143054A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |