KR100893763B1 - Method for preparing optically active alkyl 3-hydroxybutanoate derivatives - Google Patents

Abstract

The present invention relates to a method for preparing an optically active alkyl 3-hydroxybutanoate derivative, more specifically Candida antarctica lipase derived from antarctica , Pseudomonas lipase from cepacia ), Rhizomucor lipase derived from miehei ), Amano PS lipase derived from Burkholderia cepacia , Amano lipase PS-CI, Amano lipase PS-CII, or Amano lipase PS-DI, and lipase-OF catalyst , By reacting the racemic β-lactone derivatives with alcohols to perform stereoselective alcoholysis reactions, and then to the alcohols in the presence of an acid to provide optical (S) and (R) -type optically active agents. It is characterized by obtaining an active alkyl 3-hydroxybutanoate.

Optically active alkyl 3-hydroxybutanoate, lipase catalyst, racemic β-lactone

Description

METHOD FOR PREPARING OPTICALLY ACTIVE ALKYL 3-HYDROXYBUTANOATE DERIVATIVES}

The present invention relates to a method for efficiently preparing a desired optically active derivative from racemic alkyl 3-hydroxybutanoate derivatives.

Optically active 3-hydroxybutanoate derivatives are very important as precursors for the synthesis of ( 3R , 5S ) -dihydroxyhexanoate derivatives.

Optically active (3 R , 5 S ) -dihydroxyhexanoate derivatives are very important building blocks of inhibitors of 3-hydroxy-3-methylglutaryl (HMG) -CoA reducing agents that inhibit cholesterol levels in the body. Today's inhibitors of HMG-CoA reductants are the world's leading pharmaceutical market with $ 20 billion in sales, Pfizer's Lipitor (atorvastatin) is the world's best-selling drug, and Merck's Zoco ( Drugs such as simvastatin or AstraZeneca's newly developed cresto (rosuvastatin) are also known as blockbusters.

Therefore, the current optically active (3 R , 5 S ) -dihydroxyhexanoate derivatives have a market of 220 tons annually worldwide and (3 R , 5 S ) -dihydroxy supplied to various statin compounds About half of the hexanoate derivatives are obtained from microorganisms, and other production is obtained through synthesis. This compound, which has two chiral centers, must have enantiomeric excess (simply ee) value of 99.5% or more and diastereomeric excess value of 99% or more, so it is obtained by conventional chemical synthesis. This is not easy structure. Therefore, many fine chemical companies are competing for the development of new synthetic methods to produce this compound, and biocatalyst synthesis is particularly noticeable.

Most of the synthetic methods that are currently under development is (3 R, 5 S) - dihydroxy hexanoate alkyl of all, an optically active thereof precursor studies to obtain a benzoate derivative of 3-hydroxy-butanoate synthesis research of benzoate derivative is more active in progress have. In Daicel Chemical Industries and Kaneka, ethyl (S) -4-chloro-3-hydroxy from ethyl 4-chloroacetoacetate using alcohol dehydrogenase (ADH) or carbonyl reductase Bioreduction reaction systems have been developed to produce butanoate (ECHB). In this reaction system, the coenzyme is recycled using glucose dehydrogenase or formate dehydrogenase.

Similarly, Wacker Chemie and Jurich Fine Chemicals (now a branch of Codec Sheath) have developed a method for synthesizing 3-hydroxykutanoate with isolated ADH. Codecsys used the gene-shuffling technology to enhance the activity and stability of enzymes, and designed a reaction system that converts chloride groups into cyano groups using halohydrin dehalogenase enzymes. R) -4-cyano-3-hydroxybutanoate was obtained to obtain a drug building block that was further advanced. Lonza developed the reaction system on an industrial scale.

Dowpharma (Dowpharma) is a ( R ) -4-cyano-3-hydroxybutanoic acid through asymmetric hydrolysis of 3-hydroxyglutaronitrile using the Nitrile of Divers (Diversa) It developed a synthetic method (Org. Process Res . Dev . 2006 , 661). This reaction has the advantage of synthesizing glutaronitrile as a starting material with inexpensive epichlorohydrin. Divers conducted optimization studies to increase the productivity, selectivity and resistance to high concentration reactions of enzymes used in this reaction ( J. Am . Chem . Soc . 2003 , 125 , 11476). Pfenex technology was used to develop the process for production.

DSM and Daiso are separated from 1,3-dichloro-2-propanol via epichlorohydrin via 1,3-dichloro-2-propanol to separate optically active 4-chloro-3-hydroxybutanonitrile. We have developed a process for doing this. DSM worked with Enzis, an enzyme developer. This reaction is theoretically a separation process, so yield cannot be higher than 50%. However, epichlorohydrin intermediates cause racemic reactions. It happens like a dynamic dynamic kinetic resolution reaction. However, the optical activity of the final product still remains at 92% ee.

Chi Hui Wong (Chi-Huey Wong) at the Scripps Research Institute in California has two chiral centers in the reaction in a single step using the aldolase (aldolase) 10 years ago, (3 R, 5 S) - dihydroxy-hexafluoro An aldol condensation reaction was obtained to obtain noate derivatives. DSM improves 2-deoxyribose-5-phosphate aldolase (DERA), which is more than 10 times more productive than the first enzyme released and stable as starting enzyme. We are working on large scale reactions to use this process in industry. This reaction has the advantage of obtaining optically active derivatives through a single step reaction and it is very competitive in price because it uses inexpensive chloroacetaldehyde and acetaldehyde as starting materials.

In 2004, Diver screened DNA libraries and found new aldolases. The enzymes they published are highly efficient, competitive in price, can increase the scale of the reaction, and can result in products with enantiomeric excess values of at least 99.9% and diastereomeric excess values of at least 96.6%.

Ten years ago, Patel of Bristol-Myers Squibb (BMS) conducted two reduction reactions on ethyl 6-benzyloxy-3,5-dioxohexanoate using ketoductase. One result was reported. This product is also a ( 3R , 5S ) -dihydroxyhexanoate derivative having two chiral centers, as in the previous Aldolase example. BMS recently reported multiple chitoriductase reaction systems for ethyl and t -butyl chitoesters ( Tetrahedron : Asymmetry 2006 , 17 , 1589).

It is an object of the present invention to provide a method for efficiently and efficiently obtaining desired optically active alkyl 3-hydroxybutanoate derivatives from racemic β-lactone derivatives using specific lipase biocatalysts.

In order to achieve the above object, the present invention

(1) Among organic solvents, Candida antarctica lipase derived from antarctica , Pseudomonas lipase from cepacia ), Rhizomucor lipase derived from miehei ), Amano PS lipase derived from Burkholderia cepacia , Amano lipase PS-CI, Amano lipase PS-CII, or Amano lipase PS-DI, and lipase-OF catalyst , By reacting a compound of formula 1 as a racemate with an alcohol of formula 2 to undergo stereoalcoholization reaction of a compound of formula 1 as an optically active substance of ( S ) -form and ( R ) Obtaining an alkyl 3-hydroxybutanoate derivative of formula (3) as an optically active compound of the form (wherein X = CN, the compound of formula (1) in the form of ( R )-and the formula of the form ( S )) Compound of 3); And

(2) After separating the compound of formula (1) as the ( S ) -form optically active and the ester derivative of formula (3) in the ( R ) -form, the compound of formula (1) as the ( S ) -form by the decomposition of alcohol with an alcohol of formula 2 (S) - to afford a compound of formula (3) in the form of optically active body (where, X = CN days, (S) case - of the type separate from the compound of formula III (R ) Is converted to the compound of formula 3 in the form ( R )-)

Provided is a method of preparing an alkyl 3-hydroxybutanoate compound of Formula 3 as an optically active agent, comprising:

ROH

Where

X is Br, Cl, N ₃ or CN;

R is methyl, ethyl, n -propyl or n -butyl.

According to the method of the present invention, the desired alkyl 3-hydroxybutanoate derivative having optical activity can be easily obtained from the racemic raw material compound, and the obtained optically active compound has high optical purity of up to 99% ee or more. Have

The method for preparing the optically active alkyl 3-hydroxybutanoate derivative according to the present invention is shown in Scheme 1 below.

Wherein X and R are as defined above (except for ( R ) -form and ( S ) -form when X = CN).

<Step (1)>

In step (1), a lipase derived from Candida antarctica , a lipase derived from Pseudomonas cepacia , a lipase derived from Rhizomucor miehei , and a Burco-Orderia sepa in an organic solvent. Amano PS Lipase from Burkholderia cepacia (available from Sigma Aldrich Korea), Amano Lipase PS-CI (available from Sigma Aldrich Korea), Amano Lipase PS-CII (available from Sigma Aldrich Korea), Or a racemic β-lactone derivative of Formula 1 as racemate in the presence of Amano lipase PS-DI (commercially available from Sigma Aldrich Korea), Lipase-OF (commercially available from Amicogen) catalyst in the form of optical-and (R) by carrying out the alcoholysis reaction in stereoselective and allowed to react at 20 to 60 ℃ To obtain a compound with the ester derivative of formula (3) (if one, X = CN, the (R) - form and (S) - form is changed).

Preferred examples of Formula 1 as the racemate used in the reaction include 4- (bromomethyl) oxetan-2-one (4- (bromomethyl) oxetan-2-one), 4- (chloromethyl) oxetane- 2- (4- (chloromethyl) oxetan-2-one), 2- (4-oxooxetan-2-yl) acetonitrile (2- (4-oxooxetan-2-yl) acetonitrile), 4- (a Mido methyl) oxetan-2-one (4- (azidomethyl) oxetan-2-one) is mentioned.

As the organic solvent used in the reaction, diethyl ether, t -butyl methyl ether, hexane, CH ₂ Cl ₂ , tetrahydrofuran, toluene and mixtures thereof are suitable. Especially, diethyl ether and t -butyl methyl ether are used. It can be used preferably.

According to the present invention, the compound of Formula 1 as the racemate and the alcohol of Formula 2 may be used in a molar ratio of 1: 0.5 to 5, and the lipase catalyst is 10 to 100 based on 100 parts by weight of the compound of Formula 1 as the racemate. It can be used in the amount of parts by weight.

<Step (2)>

In step (2), the (S) -form optically active compound obtained in step (1) and the ester derivative of formula ( R ) in the ( R ) -form are separated, for example, by column chromatography, and then ethanol and In the same organic solvent, an (S) -form optically active compound is obtained by subjecting the ( S ) -form optically active compound of Formula 1 to an alcoholic decomposition at 20 ° C. in the presence of an acid such as p -toluenesulphonic acid ( However, when X = CN, the ( R ) -form and ( S ) -form are reversed). Thereby, an alkyl 3-hydroxybutanoate derivative of formula (3) as an optically active agent in ( R )-and ( S ) -forms can be obtained.

As such, according to the method of the present invention, the desired optically active alkyl 3-hydroxybutanoate derivatives can be easily obtained from racemic β-lactone derivatives, and the optically active compounds obtained are high optical up to 99% ee or more. Has purity.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited by the embodiment.

Synthesis of Racemic Compound

4- (Bromomethyl) oxetane-2-one, 4- (chloromethyl) oxetan-2-one, 2- (4-oxooxetane-2-one of formula 1 as the racemate used in the present invention I) The synthesis of acetonitrile, 4- (azidomethyl) oxetan-2-one was carried out as follows.

In case of 4- (bromomethyl) oxetan-2-one ( 1a ), 3-butenoic acid was synthesized by reacting with Br ₂ in about 50% yield ( Tetrahedron Lett . 1971 , 2595). For 4- (chloromethyl) oxetan-2-one ( 1b ), 3-butenoic acid was synthesized by reaction with NaOCl under a ZnCl ₂ catalyst ( Tetrahedron Lett . 2007).

Meanwhile, 2- (4-oxooxetan-2-yl) acetonitrile ( 1c ) and 4- (azidomethyl) oxetan-2-one ( 1d ) are 4- (bromomethyl) oxetan-2-one ( 1a ) was reacted with NaCN, NaN ₃ and DMSO solvent, respectively, to obtain a yield of about 50%.

Synthesis of 2- (4-oxooxetan-2-yl) acetonitrile ( 1c ): Compound 1a (1.2 mmol, 200 mg) and DMSO or DMF (5 mL) were added to a 50 mL round flask, followed by stirring. NaCN (1.8 mmol, 90 mg) was added slowly. Thereafter, the mixture was stirred at 20 ° C. for 4 hours. After adding water, the reaction was terminated and extracted using CH ₂ Cl ₂ and brine. The combined organic layers were dried over MgSO ₄ and extracted. The residue was separated by silica gel chromatography (CH ₂ Cl ₂ / MeOH = 49: 1) to give compound 1c in a yield of 54% (70 mg).

¹ H NMR (300 MHz, CDCl ₃ ), δ 5.17 (1H, m), 2.69 (4H, m); ¹³ C NMR (125 MHz, CDCl ₃ ), δ 173.8, 116.3, 64.9, 27.2, 26.3; MS, m / z (relative intensity) 111 (M ⁺ , 12), 67 (24), 56 (67), 41 (100).

Synthesis of 4- (azidomethyl) oxetan-2-one ( 1d ): Compound 1a (0.9 mmol, 150 mg) and DMSO (5 mL) were added to a 50 mL round flask and stirred, followed by NaN ₃ (1.35 mmol, 60 slowly add mg). After stirring for 4 hours, the reaction was terminated by adding water, and extracted with CH ₂ Cl ₂ and brine. The combined organic layers were dried over MgSO ₄ and evaporated. The residue was separated by silica gel chromatography (hexane / ethyl acetate = 4: 1) to give compound 1d in a yield of 50% (57 mg).

¹ H NMR (300 MHz, CDCl ₃ ), δ 4.60 (1H, m), 3.70 (1H, dd, J = 3.5, 3.5 Hz), 3.53 (1H, dd, J = 4.6, 3.6 Hz), 3.47 (1H , dd, J = 5.9, 5.9 Hz), 3.32 (1H, dd, J = 4.2, 4.2 Hz); ¹³ C NMR (125 MHz, CDCl ₃ ), δ 166.5, 68.3, 52.5, 40.6, 30.9; IR (neat) V _max : 3880, 3658, 2924, 2348, 2116, 1832 cm ⁻¹ ; MS, m / z (relative intensity) 127 (M ⁺ , 7), 71 (91), 54 (22), 43 (100), 42 (65), 41 (20), 40 (10).

<Chromatographic analysis conditions according to the type of racemic compound>

● In the case of racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a )

Quantification was carried out using gas chromatography (Agilent 6890N) equipped with lipodex-A (MN, 30m × 0.25mm ID), an optically active polar column. Analytical conditions were heated for 30 minutes at 60 ℃, increased to 100 ℃ by 1 ℃ per minute and maintained for 10 minutes. Nitrogen gas was flowed as a support | carrier, and it detected using the flame ionization detector (FID) at 220 degreeC. (S) - form in 43.92 minutes, (R) - forms of ethyl is detected in 45.06 minutes by the decomposition of ethanol alcohol ester derivatives of 4-bromo-3-hydroxy-butanoate is (S) - form ( R ) -form was detected at 63.50 minutes at 64.30 minutes to confirm the ee value. In addition, methyl 4-bromo-3-hydroxybutanoate, an ester derivative hydrolyzed by methanol, was detected at 52.8 minutes in the ( S ) -form and 53.4 minutes in the ( R ) -form to confirm the ee value. , a by-propanol in a 4-propyl ester derivative decomposition alcohol-bromo-3-hydroxy-butanoate is (S) - form in 73.9 minutes (R) - is the form is detected in 74.6 minutes to determine the ee value . Butyl 4-bromo-3-hydroxybutanoate, an ester derivative that was alcohol-decomposed with butanol, was detected at 85.9 minutes in the ( S ) -form and at 86.4 minutes in the ( R ) -form to confirm the ee value.

● In the case of racemic 4- (chloromethyl) oxetan-2-one ( rac - 1b )

Quantification was carried out using gas chromatography (Agilent 6890N) equipped with lipodex-A (MN, 30m × 0.25mm ID), an optically active polar column. Analytical conditions were heated for 40 minutes at 50 ℃, increased to 80 ℃ 1 ℃ per minute and maintained for 30 minutes. Nitrogen gas was flowed as a support, and it detected using the flame ionization detector (FID) at 280 degreeC. (S) - form in 47.60 minutes, (R) - form is detected in 49.46 minutes by ethanol in the alcohol decomposition ester derivatives of ethyl 4-chloro-3-hydroxy-butanoate is (S) - form At 71.49 minutes ( R ) -form was detected at 89.46 minutes to confirm the ee value.

● In the case of racemic 2- (4-oxooxetan-2-yl) acetonitrile ( rac - 1c )

Quantification was performed using a gas chromatography (Agilent 6890N) equipped with an optically active column, Gamma Cyclodextrin trifluoroacetyl (30 m × 0.25 mm ID of Astec, Inc.). Analytical conditions were heated for 10 minutes at 60 ℃, increased to 170 ℃ by 10 ℃ per minute and maintained for 20 minutes. Nitrogen gas was flowed at 1.0 mL / min as a carrier and detected using the flame ionization detector (FID) at 220 degreeC. The (R) -form was detected at 19.94 minutes, and the (S) -form was detected at 22.91 minutes, and ethyl 4-cyano-3-hydroxybutanoate, an ester derivative, which was alcohol-decomposed by ethanol. -3-hydroxybutanoate) was detected at 29.10 min for the ( R ) -form and 29.30 min for the ( S ) -form, confirming the ee value.

● In the case of racemic 4- (azidomethyl) oxetan-2-one ( rac - 1d )

Quantification was carried out using gas chromatography (Agilent 6890N) equipped with an optically active column, gamma cyclodextrin trifluoroacetyl (Astec, 30 m × 0.25 mm ID). Analytical conditions were heated at 60 ° C. for 2 minutes, increased to 10 ° C. per minute to 100 ° C., maintained for 15 minutes, increased to 150 ° C. at 2 ° C. per minute, and maintained for 13 minutes. Nitrogen gas was flowed at 1.0 mL / min as a carrier and detected using the flame ionization detector (FID) at 220 degreeC. Ethyl 4-azido-3-hydroxybutanoate, an ester derivative detected by ( S ) -form at 41.32 minutes and ( R ) -form at 43.82 minutes, is an alcohol-degraded ester derivative by ethanol. 3-hydroxybutanoate) was detected at 37.99 min for ( S ) -form and 38.30 min for ( R ) -form, confirming ee values.

Example 1

Three-dimensional selection by rate division of racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) using Novozym 435 (manufactured by Novozyme), a lipase catalyst derived from Candida antarctica Significant alcoholic reaction was carried out.

Specifically, in a 7 mL vial, racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) 13.2 mg (0.08 mmol), ethanol ( 2a ) 3.7 mg (0.08 mmol), Novo 10 mg of Zyme 435 and 1 mL of t -butylmethylether as a solvent were added and then reacted for 24 hours while shaking at 200 rpm using an incubator at 30 ° C. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst and then column chromatography to give a solid in the reaction solution, that is, the remaining ( S ) -form optically active 4- (bromomethyl) oxetan-2-one (( S ) -1a ) and the stereoselectively produced ester derivative (( R ) -3a ) were separated (see Scheme 2 below). The results are shown in Table 1 below.

Example  2 to 8

Except for changing the type of lipase catalyst as shown in Table 1 below, the stereo-selective esterification reaction was carried out in the same manner as in Example 1 to separate the solid in the reaction solution. At this time, in the case of Example 8, the reaction time was 48 hours. The results are shown in Table 1 below:

From Table 1, Candida antarctica lipase derived from antarctica , Pseudomonas lipase derived from cepacia ), lipase derived from Rhizomucor miehei , Amano PS lipase derived from Burkholderia cepacia , Amano lipase PS-CI, Amano lipase PS-CII, Alternatively, in Examples 1 to 8, where the rate-division of the racemates was carried out using each of Amano lipase PS-DI and lipase-OF catalyst, not only high conversion to ester compounds but also optical activity with much higher optical purity were obtained. It can be seen that it produces a sieve.

Reference Example  1: Test according to the difference of solvent type

In order to confirm the test results according to the difference in solvent type, racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) 13.2 mg (0.08 mmol), n − Butanol ( 2d ) 17.8 mg (0.24 mmol), 2 mg of Novozyme 435 and 1 mL of an organic solvent were added, and then reacted for 5 hours while shaking at 200 rpm using an incubator at 20 ° C.

As the solvent, one of diethyl ether, t -butyl methyl ether, CH ₂ Cl ₂ , tetrahydrofuran (THF), hexane, toluene, and hexane / diethyl ether (9: 1) was used. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst and then column chromatography to give a solid in the reaction solution, that is, the remaining ( S ) -form optically active 4- (bromomethyl) oxetan-2-one (( S ) -1a ) and the stereoselectively produced ester derivative (( R ) -3d ) were separated (see Scheme 3 below). The results are shown in Table 2 below.

Table 2 shows that diethyl ether, t -butyl methyl ether, hexane, toluene and hexane / diethyl ether are suitable as the organic solvent used in the method of the present invention, and tetrahydrofuran (THF) is used. When used, the reaction rate is slow, and it can be seen that the reaction does not proceed with CH ₂ Cl ₂ .

Reference Example  2: test according to temperature difference

In order to confirm the test results according to the temperature difference, a total of 5 7 mL vials, racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) 13.2 mg (0.08 mmol), butanol ( 2d ) 17.8 mg (0.24 mmol), 2 mg of Novozyme 435 and 1 mL of diethyl ether as a solvent were added and then reacted with shaking at 200 rpm in an incubator. At this time, the temperature of the incubator was 20, 30, 40, 50 and 60 ℃ to vary the reaction time. During the reaction, a small amount was ejected to check the progress of the reaction. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst and then column chromatography to give a solid in the reaction solution, that is, the remaining ( S ) -form optically active 4- (bromomethyl) oxetan-2-one (( S ) -1a ) and the stereoselectively produced ester derivative (( R ) -3d ) were separated (see Scheme 3 above). The results are shown in Table 3 below:

Reference Example  3: test according to alcohol type difference

In order to confirm the test results according to the alcohol type difference, a total of four 7 mL vials, racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) 13.2 mg (0.08 mmol), alcohol ( 2 ), 2 mg of Novozyme 435 and 1 mL of diethyl ether as a solvent were added and then reacted with shaking at 200 rpm in an incubator at 60 ° C. At this time, as alcohol ( 2 ), 3.7 mg (0.08 mmol) ethanol ( 2a ), 2.6 mg (0.08 mmol) methanol ( 2b ), 4.8 mg (0.08 mmol) n -propanol ( 2c ), 5.9 mg (0.08) mmol) of n -butanol ( 2d ) were used and reacted for 1 hour. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst and then column chromatography to give a solid in the reaction solution, that is, the remaining ( S ) -form optically active 4- (bromomethyl) oxetan-2-one (( S ) -1a ) and the stereoselectively produced ester derivative (( R ) -3 ) were separated (see Scheme 4 below). The results are shown in Table 4 below:

Wherein R is as previously defined herein.

Reference Example  4: n - Butanol  Test by difference of addition amount

In order to confirm the test results according to the difference in the amount of n -butanol ( 2d ), a total of four 7 mL vials were prepared, and then three 7 mL vials were racemic 4- (bromomethyl) oxetane-2. -one (rac-1a) 13.2 mg (0.08 mmol), n-butanol (2d), as Novozymes 435 2 mg and a solvent while shaking at 200 rpm in an incubator of the insert the 1 mL of diethyl ether, 60 ℃ 1 sigan Reacted for a while. In this case, n -butanol ( 2d ) was used in amounts of 5.9 mg (0.08 mmol), 17.8 mg (0.24 mmol) and 29.6 mg (0.04 mmol), respectively. One remaining 7 mL vial contains 13.2 mg (0.08 mmol) of racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ), 593.0 mg (8 mmol) of n -butanol ( 2d ), novozyme After adding 2 mg of 435, it was reacted for 1 hour while shaking at 200 rpm in an incubator at 60 ° C. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst and then column chromatography to give a solid in the reaction solution, that is, the remaining ( S ) -form optically active 4- (bromomethyl) oxetan-2-one (( S ) -1a ) and the stereoselectively produced ester derivative (( R ) -3d ) were separated (see Scheme 3 above). The results are shown in Table 5 below:

From the separation yield results shown in Table 5, it can be seen that the reaction rate according to the addition amount of n -butanol hardly differs.

Reference Example  5: Racemic  Test according to the difference of raw materials (substrate)

In order to confirm the test results according to the difference of racemic raw materials, racemic raw materials ( rac - 1 ), ethanol ( 2a ) (1 equivalent of the raw materials), Novozyme 435, in a total of 4 7 mL vials. And diethyl ether or t -butyl methyl ether was added as a solvent, and it reacted by shaking at 200 rpm in the 60 degreeC incubator. At this time, the reaction time was different for each. During the reaction, a small amount was ejected to check the progress of the reaction. After completion of the reaction, the reaction solution was filtered to remove the lipase catalyst, and then column chromatography was performed to obtain solids in the reaction solution, that is, a stereo-selectively produced ester (( S ) -1 ) with the remaining ( S ) -form β-lactone derivative (( S ) -1 ). A derivative (( R ) -3 ) was isolated, provided that when X = CN, a compound of formula (1) in ( R ) -form and a compound of formula (3) in ( S ) -form are obtained (see Scheme 5 below). ). The results are shown in Table 6:

Wherein X is as previously defined herein, provided that X = CN yields a compound of Formula 1 in ( R ) -form and a compound of Formula 3 in ( S ) -form.

Example  9: Synthesis of Compound 3 from Remaining Optically Active Compound 1

Through the reaction of Example 1-8 racemic starting material - remaining from (rac 1) (S) - forms of β- lactone derivative ((S) - 1) and the stereoselective ester derivative ((R generated) -3 ), and then separating, and then ( S )-form β-lactone derivatives (( S ) -1 ) by adding an acid such as p -toluenesulfonic acid in an ethanol solvent to steric selection through the alcoholic decomposition reaction Experiments were conducted to obtain ester derivatives of the ( S ) -form (see Scheme 6 below), provided that when X = CN, the compounds of Formula 1 in the ( R ) -form and the Formula 3 in the ( S ) -form being obtained in the form of a compound of formula (3)) - compound is obtained, (R) - and again the alcoholysis of a compound of general formula (I) of the form (R).

As shown in Scheme 6, racemic 4- (bromomethyl) oxetan-2-one ( rac - 1a ) is reacted with ethanol under Novozyme 435 to form the remaining ( S ) -1a and ( R ) -forms. After obtaining an ester derivative (( R ) -3a ), the remaining ( S ) -1a was reacted with an acid such as p -toluenesulfonic acid in an ethanol solvent to obtain ( S ) -3a in 80% yield. there was. (R) obtained from each reaction was ^{[α] 25 = + 10.9 (} c 1.0, EtOH) of 3a, (S) - was ^{[α] 25 = -9.9 (c} 1.0, EtOH) of 3a.

Claims (8)

(1) Among the organic solvents, a lipase derived from Candida antarctica , a lipase derived from Pseudomonas cepacia , a lipase derived from Rhizomucor miehei , and a Burco-Orderia sephacia ( In the presence of a catalyst selected from the group consisting of lipases derived from Burkholderia cepacia ), reacting a β-lactone derivative of formula (1) as a racemate with an alcohol of formula (2) to stereoselectively perform an alcoholic reaction; And (2) separating the resultant obtained in step (1) into a compound of formula (1) and a compound of formula (3), and then reacting the compound of formula (1) again with an alcohol to obtain a compound of formula (3) as an optically active agent Method for preparing an alkyl 3-hydroxybutanoate compound of Formula 3 as an optically active agent comprising: [Formula 1]

[Formula 2] ROH [Formula 3]

Where X is Br, Cl, N ₃ or CN; R is methyl, ethyl, n -propyl, or n -butyl. The method of claim 1, The compound of formula (1) is 4- (bromomethyl) oxetan-2-one, 4- (chloromethyl) oxetan-2-one, 2- (4-oxooxetan-2-yl) acetonitrile, 4 -(Azidomethyl) oxetan-2-one. The method of claim 1, The organic solvent of step (1) is selected from the group consisting of diethyl ether, t -butyl methyl ether, hexane, toluene, tetrahydrofuran (THF) and mixtures thereof. The method of claim 1, In step (1), the compound of formula 1 and the alcohol of formula 2 as racemates are used in a molar ratio of 1: 0.5-5. The method of claim 1, In step (1), the lipase catalyst is used in an amount of 10 to 100 parts by weight based on 100 parts by weight of the compound of formula 1 as the racemate. The method of claim 1, The process characterized in that the esterification reaction of step (1) is carried out at 20 to 60 ℃. The method according to any one of claims 1 to 6, The result obtained in step (1) is the compound of formula (I) as the ( S ) -form optically active compound and the ester derivative of formula (3) as the ( R ) -form optically active compound, and in step (2) the ( S ) -form After separating the compound of formula (I) as an optically active compound and the compound of formula (3) as an ( R ) -form optically active compound, the compound of formula (I) as an optically active compound of the ( S ) -form A process for preparing an alkyl 3-hydroxybutanoate compound of formula (3) as an optically active agent, characterized by obtaining a compound of formula (3) as an ( S ) -form optically active agent: [Formula 1]

[Formula 2] ROH [Formula 3]

Where X is Br, Cl or N ₃ ; R is methyl, ethyl, n -propyl, or n -butyl. The method according to any one of claims 1 to 6, The result obtained in step (1) is the compound of formula (I) as the ( R ) -form optically active compound and the ester derivative of formula (3) as the ( S ) -form optically active compound, and in step (2) the ( R ) -form After separating the compound of formula (I) as an optically active compound and the compound of formula (3) as an ( S ) -form optically active compound, the compound of formula (I) as an optically active compound of the ( R ) -form A process for preparing an alkyl 3-hydroxybutanoate compound of formula (3) as an optically active compound, characterized by obtaining a compound of formula (3) as an ( R ) -form optically active agent: [Formula 1]

[Formula 2] ROH [Formula 3]

Where X is CN; R is methyl, ethyl, n -propyl, or n -butyl.