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US3886205A
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2-Phosphono-butane-1,2,4-tricarboxylic acids
Assignee: Bayer AG
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Filing: 1974-02-11
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Granted: 1975-05-27
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Expires: 1994-02-11
Abstract
Abstract IN WHICH R is hydrogen, lower alkyl or a carboxyl group, and R1 is hydrogen or methyl, AND SALTS THEREOF, AND THEIR USE AS COMPLEX FORMERS FOR ALKALINE EARTH METAL IONS. 2-PHOSPHONO-BUTANE-1,2,4-TRICARBOXYLIC ACIDS OF THE GENERAL FORMULA
Inventors
- 👤 Hans Geffers
- 👤 Walter Radt
- 👤 Hartmut Schulz
- 👤 Reinhard Schliebs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:32
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/16; C11D3/36; C11D3/365; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/38; C07F9/3804; C07F9/3808
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
6 words
2-PHOSPHONO-BUTANE-1,2,4-TRICARBOXYLIC ACID COMPOUNDS OF THE FORMULA
Claim 2
Dependent Claim
6 words
2-PHOSPHONO-BUTANE-1,2,4-TRICARBOXYLIC ACID COMPOUNDS OF THE FORMULA
Claim 3
Dependent Claim
11 words
Compound according to claim 1 wherein R is hydrogen or methyl.
Claim 4
Dependent Claim
14 words
Compound according to claim 1 wherein such compound is 2-phosphono-butane-1,2,4-tricarboxylic acid of the formula
Claim 5
Dependent Claim
14 words
Compound according to claim 1 wherein such compound is 2-phosphono-3-methyl-butane-1,2,4-tricarboxylic acid of the formula
Claim 6
Dependent Claim
14 words
Compound according to claim 1 wherein such compound is 2-phosphono-4-methyl-butane-1,2,4-tricarboxylic acid of the formula
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) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |