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US4562298A
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Optically active nordihydroguaiaretic acid and intermediates
Assignee: BLOCK/CHEMEX GP A NEW JERSEY GENERAL PARTNERSHIP
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Filing: 1982-10-25
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Granted: 1985-12-31
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Expires: 2002-10-25
Abstract
Abstract A process for producing novel compositions including optically active molecules of nordihydroguaiaretic acid (d,1-2,3-dimethyl,1,4-bis(3,4-dihydroxyphenyl)butane) and intermediates, starting with 1,4-bis(3,4-dimethoxyphenyl)butanone, or other structurally similar composition having oxy substituents at the 3,4-phenyl positions, comprising (1) forming the corresponding butanol; (20) forming the corresponding 1,4-butane ether or siloxy composition; (3) cleaving the oxy substituent from the butane chain at the 1 and 4 positions; (4) dealkylating the phenols at the 3,4 positions to leave hydroxy substituents with hydrobromic acid reflux for 8 to 10 hours. Optical orientation is preserved throughout.
Inventors
- 👤 Robert M. Parkhurst
- 👤 Ronald S. Pardini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:22
CPC Classifications
C; C07; C07C; C07C43/00; C07C43/02; C07C43/20; C07C43/205; C07C43/2055; C07C39/00; C07C39/12; C07C39/15; C07C39/16; C07C43/23
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
25 words
A composition of matter selected from the group consisting of optically active d,1-nordihydroguaiaretic acid isomers of the formula: ##STR7## its antipode, and racemic mixtures thereof.
Claim 2
Dependent Claim
25 words
A composition of matter selected from the group consisting of optically active d,1-nordihydroguaiaretic acid isomers of the formula: ##STR7## its antipode, and racemic mixtures thereof.
Claim 3
Dependent Claim
82 words
A composition of matter selected from the group consisting of d,1-isomers of the formula: ##STR8## where R 1 , and R 2 , are lower alkyl and aralkyl, and R 3 , and R 4 are lower alkyl and aralkyl, and R 5 and R 6 are lower alkyl, alkenyl, aryl, aralkyl, or aralkenyl groups, or silyl, or substituted silyl with from one to three substituents which are lower alkyl, alkenyl, aryl, aralkyl or aralkenyl groups; its antipode, and racemic mixtures thereof.
Claim 4
Dependent Claim
82 words
A composition of matter selected from the group consisting of d,1-isomers of the formula: ##STR8## where R 1 , and R 2 , are lower alkyl and aralkyl, and R 3 , and R 4 are lower alkyl and aralkyl, and R 5 and R 6 are lower alkyl, alkenyl, aryl, aralkyl, or aralkenyl groups, or silyl, or substituted silyl with from one to three substituents which are lower alkyl, alkenyl, aryl, aralkyl or aralkenyl groups; its antipode, and racemic mixtures thereof.
Claim 5
Dependent Claim
38 words
The composition of matter selected from the group consisting of optically active d,1-isomers of the formula: ##STR9## in which R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are methyl.
Claim 6
Dependent Claim
38 words
The composition of matter selected from the group consisting of optically active d,1-isomers of the formula: ##STR9## in which R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are methyl.
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) | 1988-12-30 | 1989-07-01 | 1989-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-30 | 1993-07-01 | 1993-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-30 | 1997-07-01 | 1997-12-31 | $7700.00 | Window Closed / Lapsed |