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US4668628A Expired / Lapsed US ⏱️ 0.0 years remaining

Resolution of racemic mixtures of aliphatic acid esters

Assignee: Zeneca Inc
•
Filing: 1985-04-01
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Granted: 1987-05-26
•
Expires: 2005-04-01
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Abstract

Abstract Racemic mixtures of partially water-soluble esters defined by the formula ##STR1## wherein R and R 1 represent hydrogen and C 1 -C 4 alkyl; R 2 represents C 1 -C 4 alkyl and X represents halogen, aliphatic or aromatic groups and substituted derivatives thereof wherein R, R 1 and X are different can be resolved by reducing the water solubility of a racemic mixture of said esters by means other than changing the chemical composition of the ester, contacting the racemic mixture of esters of reduced water solubility with a lipase enzyme from Candida cylindracea capable of stereospecifically resolving the racemic mixture of hydrolysis and stereospecifically resolving the racemic mixture.

Inventors

  • 👤 Samun K. Dahod
  • 👤 Patricia Siuta-Mangano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 14:19
CPC Classifications
C; C12; C12P; C12P41/00; C12P41/003; C12P41/005; C12P7/00; C12P7/40

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 84 words
A process for enzymatically resolving racemic mixtures of partially water-soluble esters which are soluble to more than 25 millimolar in water at 25° C. comprising reducing the water solubility of a racemic mixture of said esters to less than 25 millimolar by means other than changing the chemical composition of the ester, contacting the racemic mixture of esters of reduced water solubility with a lipase enzyme from Candida cylindracea capable of stereospecifically resolving the racemic mixture by hydrolysis and stereospecifically resolving the racemic mixture.
Claim 2
Dependent Claim 84 words
A process for enzymatically resolving racemic mixtures of partially water-soluble esters which are soluble to more than 25 millimolar in water at 25° C. comprising reducing the water solubility of a racemic mixture of said esters to less than 25 millimolar by means other than changing the chemical composition of the ester, contacting the racemic mixture of esters of reduced water solubility with a lipase enzyme from Candida cylindracea capable of stereospecifically resolving the racemic mixture by hydrolysis and stereospecifically resolving the racemic mixture.
Claim 3
Dependent Claim 198 words
A process for enzymatically resolving racemic mixtures of partially water-soluble esters which are soluble in water to more than 25 millimolar at 25° C. defined by the formula ##STR3## wherein R and R 1 represent hydrogen and C 1 -C 4 alkyl; R 2 represents C 1 -C 4 alkyl and X represents halogen, aliphatic or aromatic groups and substituted derivatives thereof with the proviso that the compounds are at least partially water soluble wherein R, R 1 and X are different comprising reducing the water solubility of a racemic mixture of said esters to below about 25 millimolar by means other than changing the chemical composition of the ester selected from the group consisting of (a) adding a salt to an aqueous solution of the lipase enzyme in which at least some of the ester is in solution in an amount sufficient to lower the solubility of the ester in the aqueous solution; and (b) a combination of (a) with a water immiscible organic solvent, contacting the racemic mixture of esters of reduced water solubility with a lipase enzyme from Candida cylindracea capable of stereospecifically resolving the racemic mixture by hydrolysis and stereospecifically resolving the racemic mixture.
Claim 4
Dependent Claim 198 words
A process for enzymatically resolving racemic mixtures of partially water-soluble esters which are soluble in water to more than 25 millimolar at 25° C. defined by the formula ##STR3## wherein R and R 1 represent hydrogen and C 1 -C 4 alkyl; R 2 represents C 1 -C 4 alkyl and X represents halogen, aliphatic or aromatic groups and substituted derivatives thereof with the proviso that the compounds are at least partially water soluble wherein R, R 1 and X are different comprising reducing the water solubility of a racemic mixture of said esters to below about 25 millimolar by means other than changing the chemical composition of the ester selected from the group consisting of (a) adding a salt to an aqueous solution of the lipase enzyme in which at least some of the ester is in solution in an amount sufficient to lower the solubility of the ester in the aqueous solution; and (b) a combination of (a) with a water immiscible organic solvent, contacting the racemic mixture of esters of reduced water solubility with a lipase enzyme from Candida cylindracea capable of stereospecifically resolving the racemic mixture by hydrolysis and stereospecifically resolving the racemic mixture.
Claim 5
Dependent Claim 31 words
The process as recited in claim 2 wherein R is C 1 -C 4 alkyl, R 1 is hydrogen, R 2 is C 1 -C 4 alkyl and X is halogen.
Claim 6
Dependent Claim 24 words
The process as recited in claim 2 wherein R is C 1 -C 2 alkyl and R 2 is C 1 -C 2 alkyl.
Claim 7
Dependent Claim 19 words
The process as recited in claim 2 wherein R is hydrogen, R 1 is methyl, and X is p-hydroxyphenyl.
Claim 8
Dependent Claim 12 words
The process as recited in claim 5 wherein R 2 is methyl.
Claim 9
Dependent Claim 19 words
The process as recited in claim 2 wherein R is hydrogen, R 1 is methyl and X is p-hydroxyphenoxy.
Claim 10
Dependent Claim 12 words
The process as recited in claim 7 wherein R 2 is methyl.
Claim 11
Dependent Claim 15 words
The process as recited in claim 3 wherein R and R 2 are each methyl.
Claim 12
Dependent Claim 11 words
The process as recited in claim 9 wherein X is chlorine.
Claim 13
Dependent Claim 16 words
The process as recited in claim 2 wherein X is a halogen of chlorine or bromine.
Claim 14
Dependent Claim 23 words
The process as recited in claim 2 wherein said solvent is selected from the group consisting of carbon tetrachloride, perchloroethylene and mixtures thereof.
Claim 15
Dependent Claim 13 words
The process as recited in claim 8 wherein said solvent is carbon tetrachloride.
Claim 16
Dependent Claim 39 words
The process as recited in in claim 2 wherein said salt is an at least partially water-soluble salt selected from the group consisting of alkali metal and alkaline earth metal halides, carbonates, bicarbonates, phosphates, sulfates, nitrates and mixtures thereof.
Claim 17
Dependent Claim 18 words
The process as recited in claim 14 wherein said salt is sodium chloride, sodium bicarbonate or mixtures thereof.
Claim 18
Dependent Claim 14 words
The process as recited in claim 2 wherein said esters are 2-chloropropionic acid esters.
Claim 19
Dependent Claim 23 words
The process as recited in claim 16 wherein said solvent is selected from the group consisting of carbon tetrachloride perchloroethylene and mixtures thereof.
Claim 20
Dependent Claim 18 words
The process as recited in claim 16 wherein said salt is sodium chloride, sodium bicarbonate or mixtures thereof.
Claim 21
Dependent Claim 12 words
The process as recited in claim 16 wherein the ester is methyl.
Claim 22
Dependent Claim 23 words
The process as recited in claim 16 wherein said racemate is resolved using said water insoluble solvent in combination with said insolubilizing salt.
Claim 23
Dependent Claim 21 words
The process as recited in claim 20 wherein the temperature of hydrolysis ranges from about 2° C. to about 8° C.

References Cited (Backward Citations)

JPS5794295A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-05-25 1990-11-24 1991-05-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-05-25 1994-11-24 1995-05-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-05-25 1998-11-24 1999-05-26 $7700.00 Window Closed / Lapsed

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