JPH02207799A - Method for isolating optically active 3-phenyl-glycidic acid ester compound - Google Patents

Abstract

PURPOSE:To collect optically active 3-phenylglycidic acid esters by dividing a specific enzyme reaction product into two phases using a mixed solvent system of water immiscible organic solvent and water in the presence of an aqueous sulfurous acid ion donor. CONSTITUTION:A racemic 3-phenylglycidic acid ester which may have substituent groups on phenyl group is reacted with an asymmetric hydrolase and the optically active body in the above-mentioned racemic body is hydrolyzed to produce enzyme reaction product. Then the enzyme reaction product is divided into two phases using two phase mixed solvent system of water immiscible organic solvent and water in the presence of a hydrogen sulfite ion donor and optically active 3-phenylglycidic acid ester compounds which are undecomposed other optically active bodies are isolated from an organic solvent phase. The applicable enzyme reaction liquid is a reaction liquid by an asymmetric hydrolase in one group of lipase or esterase.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for isolating optically active 3-phenylglycidic acid ester compounds.

[Prior art]

Optically active 3-phenylglycidic acid ester compounds are important compounds as intermediates for the synthesis of diltiazem hydrochloride, which is useful as a coronary vasodilator, and various other pharmaceutical compounds. 3
A method of hydrolyzing -(4-methoxyphenyl)glycidic acid methyl ester to give the corresponding carboxylic acid, optically resolving this carboxylic acid with optically active amines, and then esterifying it (JP-A-60-13775, JP-A-60-13775). -137
76) is known.

[Problem to be solved by the invention]

However, the above-mentioned known method has the disadvantage that it requires a large number of steps and that the desired optically active trans-3-(4-methoxyphenyl)glycidic acid methyl ester can only be obtained as an oil with low purity.

As a method for overcoming the above-mentioned difficulties, the present applicant first applied an asymmetric hydrolase to a racemic 3-phenylglycidic acid ester compound to hydrolyze one of the optically active forms, and then added an enzyme reaction solution to the compound. A patent application has been filed for a method for producing optically active 3-phenylglycidic acid ester compounds, which involves collecting the other undecomposed optically active substance.
No. 221016), this method is an excellent method for producing optically active esters in the form of crystals from the racemic 3-phenyl glycidate compound as a raw material. There still remained points to be improved in the process of collecting the optically active ester.

That is, in the above method, the enzymatic reaction was carried out in a two-phase mixed solvent of a water-immiscible organic solvent and water, since both the racemic form and the optically active form of the 3-phenylglycidic acid ester compound are poorly soluble in water. After that, it should be convenient to collect the organic solvent phase and collect the desired optically active 3-phenylglycidate ester compound from the organic solvent phase.
For some reason, the yield of crystals of the target product was not satisfactory.

Although the cause is not clear, it is presumed that various by-products are mixed into the organic solvent phase as impurities, and this impedes crystallization of the target product.

[Structure and effects of the invention]

As a result of various studies, the present inventors discovered that when isolating an optically active 3-phenylglycidic acid ester compound from an enzyme reaction solution, an organic solvent phase and an aqueous phase were separated in the coexistence of a hydrogen sulfite ion donor. The present inventors have discovered that the yield of crystals of the target product can be significantly improved by collecting the target product from the organic solvent phase after separating the target product, and have completed the present invention.

That is, the present invention is based on the general formula (however, ring A is a phenyl group which may have a substituent,
R represents an ester residue. ) The enzyme-reacted product obtained by reacting an asymmetric hydrolase to the racemic 3-phenylglycidic acid ester compound shown in the formula to hydrolyze one of the optically active forms in the presence of a hydrogen sulfite ion donor. Below, an optically active 3-phenyl glycide is prepared by separating into two phases using a two-phase mixed solvent system of a water-immiscible organic solvent and water, and collecting the other undecomposed optically active substance from the organic solvent phase. This is a method for isolating acid ester compounds.

The method of the present invention can be applied to enzyme reaction solutions of various 3-phenylglycidic acid ester compounds.

For example, in the above general formula CI), the ring is a phenyl group, or a lower alkylphenyl group, a lower alkoxyphenyl group, or a halogenophenyl group, and the ester residue R is a lower alkyl group (for example, a methyl group, an ethyl group, etc.). It can be applied to the isolation of racemic 3-phenylglycidic acid ester compounds (group) from an enzyme reaction solution obtained by asymmetric hydrolysis.

The enzyme reaction solution to which the method of the present invention can be applied is a reaction solution using a group of asymmetric hydrolases called lipases or esterases, but the enzymes may be derived from microorganisms, animals, or plant cells. It may be extracted from microbial cells, animal cells, or plant cells containing hydrolytic enzymes by a known method, or it may be a commercially available product. Specifically, for example, Chromobacterium viscosum, Pseudomonas fragi, Mucor javanicus, Rhizopus alizas, Rhizopus deremer,
Lipase derived from Rhizopus javonicus, Rhizopus nibius, Candida cilinthrusia, lipase derived from pig pancreas, esterase derived from pig liver, cholesterol esterase derived from Candida rugosa, etc. are commercially available, and any of these can be used. But that's fine.

In addition to the enzyme itself, microorganisms that have the ability to produce the above-mentioned hydrolytic enzymes (for example, molds such as Absidia, bacteria such as Achromobacter, yeast such as Candida, actinomycetes such as Nocardia, etc.) ) culture solution, bacterial cells or treated bacterial cells (e.g., freeze-dried bacterial cells, acetone-dried bacterial cells, bacterial autolysates, bacterial cell extracts, ground bacterial cells, sonicated bacterial cells). Furthermore, enzymes, microbial cells, or treated bacterial cells as described above may be used in known methods such as polyacrylamide method, sulfur-containing polysaccharide gel method (carrageenan gel method, etc.), alginate gel method, agar gel method, etc. It is also possible to use one that has been fixed by a method.

The enzyme reaction solution to which the present invention can be applied is preferably one obtained by enzymatic reaction in a two-phase mixed solvent of a water-immiscible organic solvent and water. Toluene, xylene, benzene, carbon tetrachloride, chloroform, trichloroethylene, chlorobenzene, methyl isobutyl ketone, etc. are preferably used.

The enzyme reaction is carried out at a substrate concentration of approximately 0.05 to 20%, particularly 2 to 20%, at room temperature or under heating, preferably at 10%.
It is suitably carried out at a temperature of -50°C, particularly preferably 25-40°C.

In order to isolate the desired optically active 3-phenylglycidic acid ester compound from the enzymatic reaction product, the resultant is subjected to an enzymatic reaction in a two-phase mixed solvent of a water-immiscible organic solvent and water. When the reaction solution is obtained, it is preferably carried out by coexisting a hydrogen sulfite ion donor in the reaction solution, separating the organic solvent phase and the aqueous phase, and then collecting the target product from the organic solvent phase. can do. On the other hand, if the reaction product does not contain the above organic solvent and/or water, add these solvents to form a two-phase mixed solvent system and coexist with the bisulfite ion donor, and then proceed in the same manner as above. This can be suitably carried out by separating an organic solvent phase and an aqueous phase, and then collecting the target product from the organic solvent phase.

For example, when a target product is to be isolated from an enzyme reaction solution as described above, a hydrogen sulfite ion donor is first added and mixed with the enzyme reaction solution. Examples of hydrogen sulfite-ion donors include alkali metal hydrogen sulfites such as sodium hydrogen sulfite and potassium hydrogen sulfite, and the amount added is 0.25 to 0.75 molar ratio to the substrate, especially 0.4
It is preferable that the molar ratio is 0 to 40.
Preferably, the reaction is carried out at a temperature of 20 to 30°C.

Next, the organic solvent phase and the aqueous phase are separated, and ! i1 The desired optically active 3-phenylglycidic acid ester compound (1) is collected from the solvent phase. Collection of the target product from the organic solvent phase can be carried out according to a conventional method, for example, by concentrating the organic solvent phase, adding a solvent (e.g., isopropyl alcohol) to the residue and cooling it, the target product can be obtained. The optically active 3-phenylglycidic acid ester compound (1) can be obtained as a crystal.

According to the method of the present invention, the optically active 3-phenylglycidic acid ester compound (+) can be obtained in high yield as high-purity crystals, but this is probably due to the presence of impurities in the organic solvent. This is thought to be because the purity of the target product increases due to the hydrogen sulfite ion coexisting with the by-products, which transfers to the aqueous phase, and as a result, crystallization from the organic solvent phase becomes easier.

Hereinafter, the method of the present invention will be specifically explained with reference to Examples.

Example 208 g of racemic trans-3-(4-methoxyphenyl)glycidic acid methyl ester was dissolved in 11 toluene, and 4 g (1.44 million units) of a commercially available lipase agent and sodium lauryl sulfate 1100 III were added to a 0.5 M phosphate buffer. (pH 7, 0) Add the solution dissolved in 3301 nl and stir at 30°C for 4 hours. Add 57 g of sodium bisulfite to the enzymatic reaction completed solution, stir at 25 to 30°C for 10 minutes, and then leave to stand for 1 hour.

The toluene layer is separated, dried, and the solvent is distilled off.

Isopropyl alcohol is added to the residue, cooled, and the precipitated crystals are collected by filtration. By washing the crystals with isopropyl alcohol and drying them under reduced pressure, (2R,3S) -3
85 g of -(4-methoxyphenyl)glycidic acid methyl ester are obtained.

Yield from (2R,3S) body in raw material racemic body: 82%
M, P,: 8B, 0 ~ 89.5 °C [α
)" Knee 208° (C-0,2, methanol) Purity 100% For comparison, when the enzyme reaction finished solution was treated in the same manner as above without adding sodium bisulfite, (2R
, 3S) -3-(4-methoxyphenyl)glycidic acid methyl ester was obtained in an amount of 66 g.

Claims (5)

[Claims] (1) Enzyme reaction product obtained by hydrolyzing one of the optically active forms by allowing an asymmetric hydrolase to act on racemic 3-phenylglycidic acid ester, which may have a substituent on the phenyl group. , using a two-phase mixed solvent system of a water-immiscible organic solvent and water in the coexistence of a bisulfite ion donor to separate into two phases, and collect the other undecomposed optically active substance from the organic solvent phase. A method for isolating an optically active 3-phenylglycidic acid ester compound, characterized by: (2) A racemic 3-phenylglycidic acid ester, which may have a substituent on the phenyl ring, is treated with an asymmetric hydrolase in a two-phase mixed solvent of a water-immiscible organic solvent and water. It is characterized by hydrolyzing one optically active substance, separating an organic solvent phase and an aqueous phase in the coexistence of a hydrogen sulfite ion donor, and then collecting the other undecomposed optically active substance from the organic solvent phase. A method for isolating an optically active 3-phenylglycidic acid ester compound. (3) The isolation method according to claim 1 or 2, wherein the enzyme is lipase. (4) The undecomposed optically active substance to be collected is (2R,3S)-
4. The isolation method according to claim 1, 2 or 3, wherein the 3-(4-methoxyphenyl)glycidic acid lower alkyl ester is used. (5) The isolation method according to claim 1, 2, 3 or 4, wherein the hydrogen sulfite ion donor is an alkali metal hydrogen sulfite.