US5039819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diphosphonate intermediate for preparing an antihypercalcemic agent
Assignee: Merck Sharp & Dohme LLC
•
Filing: 1990-09-18
•
Granted: 1991-08-13
•
Expires: 2010-09-18
Abstract
Abstract Described is a new diphosphonate intermediate useful in a new process for producing 4-amino-1-hydroxybutylidene-1,1-bisphosphonic acid (ABP), a new antihypercalcemic agent. The process involves a 3-step sequence starting with 4-phthalimidobutanoyl chloride which can be practiced as a "one-pot" reaction sequence, without employing PCl 3 or H 3 PO 3 . The new intermediate has the structure: ##STR1## where n=1-5.
Inventors
- 👤 Gerard R. Kieczykowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:28
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/38; C07F9/3804; C07F9/3839; C07F9/3873; C07F9/547; C07F9/553; C07F9/5537
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
8 words
A compound of the formula: ##STR9## where n=1-5.
Claim 2
Dependent Claim
8 words
A compound of the formula: ##STR9## where n=1-5.
Claim 3
Dependent Claim
9 words
The compound of claim 1 of the formula: ##STR10##
References Cited (Backward Citations)
US4407761A
Cited
US4922007A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |