Method for separating of optically pure thiophene compounds using simulated moving bed chromatography
View Patent ↗Disclosed herein is a method of producing an optically active thiophene-based compound using a simulated moving bed adsorption separation process, and more specifically, a method of continuously separating a racemic thiophene-based compound into its optically active thiophene-based compounds having high purity, through optical resolution using the simulated moving bed process. According to the method of the current invention, a racemic mixture of a thiophene-based compound can be continuously separated into its optically active thiophene-based compounds having high purity, which is an intermediate of optically active dorzolamide acting as a topical therapeutic agent for glaucoma, using a simulated moving bed adsorption separation technique, thereby increasing industrial usability.
1. A method for separating an optically active thiophene-based compound, which comprises continuously separating a thiophene-based racemic mixture represented by the following Formula 1 into (S)-thiophene-based compound and (R)-thiophene-based compound, respectively, through optical resolution by a simulated moving bed (SMB) adsorption separation process in which an eluent is a mixture of acetonitrile and isopropanol, and an adsorbent comprises a support coated with a polysaccharide derivative:
Wherein, X is S or SO 2 ,
Y is H, SO 3 H, or SO 2 NH 2 , and
R is a linear or branched, saturated or unsaturated carbon chain having 1-20 carbons, a saturated or unsaturated carbon ring having 3-20 carbons, or a carbon chain or carbon ring containing a benzene ring having 6-20 carbons.
2. The method according to claim 1 , wherein the polysaccharide derivative is an amylose or cellulose derivative.
3. The method according to claim 2 , wherein the polysaccharide derivative is an amylose derivative having a subgroup of 3,5-dimethylphenylcarbamate or (S)-α-amethylbenzylcarbamate.
4. The method according to claim 1 , wherein the support is silica.
5. The method according to claim 4 , wherein the silica support is a spherical silica having a particle diameter of 1-50 μm, and an average pore size of 1 nm to 10 μm.
6. The method according to claim 1 , wherein the mixture of acetonitrile and isopropanol has a volumetric ratio of 80:20-98:2.
7. The method according to claim 1 , wherein the separating is performed in a temperature range of 10-40° C.
8. The method according to claim 7 , wherein the separating is performed in a pressure range of 1-50 bar.
9. The method according to claim 1 , further comprising recovering either (S)-thiophene-based compound or (R)-thiophene-based compound, in which the recovered optical isomer of the thiophene-based compound has an optical purity of 99% ee or more.
10. The method according to claim 9 , further comprising racemizing the non-recovered optical isomer of the thiophene-based compound to reuse as a material for the optical resolution.
11. The method according to claim 10 , wherein the racemizing step is performed by adding a basic material to the non-recovered optical isomer of the thiophene-based compound, the basic material being selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, barium hydroxide, magnesium hydroxide, calcium hydroxide, sodium bicarbonate, potassium bicarbonate, lithium carbonate, sodium carbonate, potassium carbonate, ammonia, organic amine compounds including methylamine, ethylamine, propylamine, butylamine, pyrrolidine, piperidine, piperazine, pyrrole, and pyridine, and combinations thereof.
12. The method according to claim 1 , further comprising recovering both of the respectively separated (S)-thiophene-based compound and (R)-thiophene-based compound, in which each of the two recovered optical isomers has an optical purity of 97% ee or more.