JP3183756B2 - Method for producing optically active 1-benzyloxy-2-alkanol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing optically active 1-benzyloxy-2-alkanol, and more particularly, to an R-form of a mixture of R-form and S-form of 1-benzyloxy-2-acetoxyalkane by an enzymatic method. 1-benzyloxy-
The present invention relates to a method for producing a 2-alkanol.

[0002]

2. Description of the Related Art Optically active 1,2-alkyldiol derivatives are extremely important compounds as raw materials for synthesizing new materials such as pharmaceuticals, agricultural chemicals, other physiologically active substances, and ferroelectric liquid crystal materials.

[0003] Conventionally, methods for producing optically active 1,2-alkyldiol derivatives include Corynebacterium,
Utilizing the enzymatic activity of a microorganism belonging to a specific genus including the genus Micrococcus, the racemic 1-aryloxy-2-alkylacetate is converted to the R-form 1-aryloxy-2-
A method for producing alkanol is known (Japanese Patent Laid-Open No.
No. 103691, Bioscience Biotechnology Biochemistry (Biosci. Bio)
tech. Biochem. ,) 57, 1334-1
337 (1993)).

[0004]

However, in the R-form 1-aryloxy-2-alkanol obtained by the above method, since the aryloxy group is a very chemically stable substituent, this substituent is not used. It is very difficult to convert to other functional groups. For this reason, the use of the optically active compound as an industrial raw material was very limited.

[0005] Further, in such a method, 1-aryloxy-2 is allowed to act on the microorganism or a treated product of the microorganism.
The optimal substrate concentration of the racemic alkyl acetate is 0.1.
When the compound is allowed to act in excess of the substrate concentration, the R-form 1-aryloxy-
There was a problem that the hydrolysis rate of 2-acetoxyalkane was extremely reduced. Therefore, it has been difficult to produce the R-form 1-aryloxy-2-alkanol as an optically active 1,2-alkyldiol derivative in an industrially satisfactory amount by this method.

[0006]

SUMMARY OF THE INVENTION In view of the above background, the present inventors have developed a 1,2-alkyldiol derivative,
We have been intensively studying a method for efficiently obtaining a compound having a structure in which another functional group can be easily introduced into the oxy group at position 1. As a result, since it is easily removed by hydrogen reduction or the like, in organic synthesis, 1-benzyloxy-2-acetoxyalkane in which the 1-hydroxyl group is protected with a benzyl group, which is a very general protective agent for a hydroxyl group, is used as a substrate. By applying a culture solution, cells or treated cells of a specific microorganism to this, the optical activity 1-
It has been found that benzyloxy-2-alkanol can be produced favorably, and the present invention has been completed.

That is, the present invention belongs to the genus Corynebacterium or the genus Micrococcus, and comprises 1-benzyloxy-2
-A culture solution of a microorganism having the ability to selectively hydrolyze the R-form to produce an R-form 1-benzyloxy-2-alkanol when acted on a mixture of the R-form and the S-form of acetoxyalkane; The method is characterized in that the cells or the treated cells are allowed to act on a mixture of the R-form and the S-form of the 1-benzyloxy-2-acetoxyalkane, and the resulting R-form 1-benzyloxy-2-alkanol is collected. Is a method for producing an optically active 1-benzyloxy-2-alkanol.

In the present invention, 1-benzyloxy-2
-As the acetoxyalkane, a mixture of R-form and S-form is used. In that case, the mixing ratio of the R-form and the S-form is not particularly limited. Usually, a so-called racemic mixture in which the R-form and the S-form are mixed in an equal amount is used. Here, as the alkane, propane, butane, pentane,
A lower alkane having 3 to 10 carbon atoms such as hexane is preferably used. 1-benzyloxy-2 used in the present invention
Specific examples of -acetoxyalkane include 1-benzyloxy-2-acetoxypropane, 1-benzyloxy-2-acetoxybutane, and 1-benzyloxy-2-.
Examples thereof include acetoxypentane and 1-benzyloxy-2-acetoxyhexane. Among these, 1-benzyloxy-2- acetoxypropane is most preferably used. Such 1-benzyloxy-2-acetoxyalkane usually reacts an acetylating agent such as acetic anhydride on 1-benzyloxy-2-alkanol obtained by reacting alkylene oxide with benzyl alcohol in the presence of a base catalyst. It is manufactured by

In the present invention, the 1-benzyloxy-2
A mixture of the R-form and the S-form of acetoxyalkane (hereinafter, also simply referred to as a substrate mixture) belonging to the genus Corynebacterium or the genus Micrococcus. A culture solution, cells or treated cells of microorganisms having the ability to degrade are acted on. As a result, only the R-form of the substrate mixture is selectively hydrolyzed, and the optically active R-form 1-benzyloxy-2
Alkanol is formed. Here, as the microorganism, any microorganism having the above properties can be used without any limitation. Specifically, for example, Corynebacterium glutamicum ATCC
13032), Corynebacterium glutamicum
terium glutamicum ATCC 13059), Micrococcus luteus IFO 3333 and the like are preferably used.

As the medium used for culturing the above-mentioned microorganism, a known medium is used. For example, glucose, sucrose, fructose, glycerol, sorbitol, honey, carbon sources such as soluble starch,
Meat extract, yeast extract, polypeptone, peptone, nitrates, nitrogen sources such as ammonium salts, and especially those containing inorganic salts such as potassium phosphate monobasic, potassium phosphate dibasic, sodium chloride, magnesium sulfate and the like Not limited.

[0011] The medium may be liquid or solid. The culture method may be any of static culture, shaking culture, and aeration and agitation culture, but liquid culture by aeration and agitation is suitable for mass culture. The culture temperature is 15 to 45 ° C,
The culture is preferably performed at 20 to 40 ° C., usually for 20 to 48 hours.

In the present invention, the method of reacting the above-mentioned substrate mixture with a culture solution, cells or treated cells of the microorganism is limited to the method of acting on the substrate which is usually carried out in an enzymatic reaction utilizing microorganisms. Adopted without being done. For example, there is a method in which the above-mentioned substrate mixture is added to a culture medium of the microorganism to make it act. In this case, the substrate mixture may be added to the medium from the beginning or may be added during the culturing.

[0013] The substrate mixture may be allowed to act on the substrate mixture in a mineral or organic solvent which does not inhibit the reaction, preferably in an aqueous solvent. In the present invention, the treated cells are, for example, washed cells, dried cells, ground cells, autolysed cells, ultrasonically treated cells, cell extracts, or the cells. A lipase obtained by purifying an extract or the like is used without any particular limitation. Here, as the cells, the cell extract, and the lipase obtained by producing the cell extract, those immobilized by a known method for immobilizing cells and enzymes can also be used.

In the present invention, the concentration of the substrate mixture when the culture solution, the microbial cells, or the processed microbial cells of the microorganism is allowed to act as described above is not particularly limited. Normal,
It may be appropriately selected from a wide range of 0.1 to 30% by weight, preferably 0.5 to 15% by weight. As described above, when a mixture of the R-form and the S-form of 1-aryloxy-2-alkyl acetate is hydrolyzed by the enzymatic action of a microorganism, the hydrolysis rate becomes extremely high when the concentration of the substrate is higher than 2%. It is going down. On the other hand, as in the present invention, a mixture of R-form and S-form of 1-benzyloxy-2-acetoxyalkane was used as a substrate, which was hydrolyzed by the enzymatic action of a microorganism belonging to the genus Corynebacterium or Micrococcus. In this case, the hydrolysis rate of the R-form is favorably maintained up to a high concentration range where the substrate concentration reaches 30% by weight.

In the present invention, the pH of the reaction medium when a culture solution, cells or treated cells of a microorganism is allowed to act on the substrate mixture is not particularly limited. Preferably, it is in the range. Further, the concentration of the cells or the treated cells at the time of the action cannot be determined unconditionally due to differences in the degree of purification of the treated cells, but usually, the protein amount is 0.05 to 10% by weight. Is appropriately adopted from the range of The working temperature is not particularly limited, but is preferably 10 to 50 ° C, preferably 30 to 50 ° C.
A range of 45 ° C. is preferred. The action time cannot be determined unconditionally because it is determined by the substrate concentration and the type of strain used, but it is usually sufficient to act for 3 to 60 hours.

After the hydrolysis of the substrate mixture is performed as described above, the generated R-form 1-benzyloxy-2-alkanol is collected. The collection of the product is not particularly limited, and can be easily carried out by extracting with a solvent such as ethyl acetate or hexane.

[0017]

According to the present invention, the culture solution, cells or treated cells of the microorganism belonging to the genus Corynebacterium or Micrococcus are treated with R-form of 1-benzyloxy-2-acetoxyalkane and S-form. By acting on the mixture of the isomers, the R-form 1-benzyloxy-2-alkanol can be obtained with a good hydrolysis rate even when the concentration of the substrate is high. This 1-benzyloxy-2-alkanol has a structure in which the benzyl group can be easily removed by hydrogen reduction or the like. Therefore, the compound introduces various functional groups after the benzyl group is removed in this manner. Thereby, it can be effectively used as an industrial raw material for various uses requiring optical activity. Therefore, the present invention relates to optical activity 1
It is very useful as a method for efficiently obtaining -benzyloxy-2-alkanol.

[0018]

Hereinafter, the present invention will be described with reference to examples.
The present invention is not limited to these embodiments.

Example 1 (1) Synthesis of Substrate In a four-necked flask equipped with a stirrer and a thermometer, 232.3 g (4 mol) of propylene oxide, 216.3 g (2 mol) of benzyl alcohol, and 13.6 g of sodium ethoxide ( 0.2 mol), and the mixture was heated to 40 ° C. and stirred for 10 hours. After completion of the reaction, 400 ml of water and 400 ml of methylene chloride were added, the methylene chloride phase was separated, and this was dried over magnesium sulfate. Methylene chloride was distilled off from the obtained methylene chloride solution, and 5
Distillation was performed at 120 ° C. under a pressure of 27 ° C. to obtain 279.2 g (yield 84%) of 1-benzyloxy-2-propanol. 176.3 g (1.1 mo) of this alcohol
l) and 410.0 g (4 mol) of acetic anhydride were added to the same reactor as above, and reacted at 70 ° C. for 7 hours and at 90 ° C. for 5 hours. After completion of the reaction, unreacted acetic anhydride and acetic acid produced as a by-product were distilled off by an evaporator, and the remaining liquid was distilled off at 5 Torr.
After distillation under reduced pressure at 130 ° C., the target compound 1-
191.8 g (87% yield) of a racemic form of benzyloxy-2-acetoxypropane was obtained.

(2) (R) -1-benzyloxy-2-
Production of propanol The culture of bacteria was 2.0% glucose, 1.0% saccharose, 1.0% meat extract, 0.5% peptone, 0.2% yeast extract, 0.3% sodium chloride, 0.4% 500 m of a medium containing potassium monophosphate, 0.2% potassium phosphate, 0.1% magnesium sulfate and heptahydrate, pH 7.0
1 to a 2L shoulder flask and add Corynebacterium
Glutamicum ATCC 13059 bacteria at 30 ° C for 48
Time shaking culture was performed. After the culture, the supernatant was removed by centrifugation, and 50 mM phosphate buffer (pH 7.
0) Washed twice with 50 ml. 250 mg of the obtained cells
Is dispersed in 5 ml of a phosphate buffer (pH 7.0),
A racemic 1-benzyloxy-2-acetoxypropane was added so that the substrate concentration became 5.0% (W / V), followed by shaking culture at 30 ° C. for 24 hours. After the reaction, 5 ml of ethyl acetate was added for extraction. When this extract was analyzed by high performance liquid chromatography, it was confirmed that (R) -1 had a hydrolysis rate of 50.6% and an optical purity of 92.4%.
-Benzyloxy-2-propanol was obtained.

The analysis conditions for the optical purity were as follows.

Column: Chiralcell OD
(4.6 × 250 mm) Daicel Chemical Industries, Ltd. Solvent: 5% isopropyl alcohol / 95% n-hexane Flow rate: 0.3 ml / min Detection: 254 nm Comparative Example 1 1-benzyloxy-2-acetoxypropane as a substrate , Except that the racemic 1-phenoxy-2-acetoxypropane was used in place of the racemate and the shaking culture period of the cells in the presence of the substrate was changed from 24 hours to 36 hours.
The same operation as in Example 1 was performed. The hydrolysis ratio of (R) -1-phenoxy-2-propanol was only 15.8%.

Example 2 The same operation as in Example 1 was performed except that the substrate concentration was changed as shown in Table 2.

Table 2 shows the cultivation time, hydrolysis rate and optical purity.

[0025]

[Table 1]

Example 3 Corynebacterium glutamicum ATCC 130
After culturing 59 bacteria in 500 ml of the same medium as in Example 1 in a 2 l shoulder flask for 48 hours, centrifugation was performed, the supernatant was removed, and 50 mM phosphate buffer (pH 7.0) was removed under ice-cooling.
0), and washed twice with 50 ml. Ice-cooled 50m
An appropriate amount of M phosphate buffer (pH 7.0) was added and suspended, and ice-cooled acetone was added thereto three times in volume, followed by stirring. After washing twice with ice-cold acetone, freeze-drying was performed to obtain acetone-dried cells.

The same reaction as in Example 1 was carried out in 5 ml of 50 mM phosphate buffer using the cells obtained by the above method and 1-benzyloxy-2-acetoxypropane in amounts and concentrations as shown in Table 3. Was. Table 3 shows the results.

[0028]

[Table 2]

Example 4 Micrococcus luteus IFO 333 as strain
The same operation as in Example 1 was performed except that three bacteria were used. As a result, the hydrolysis rate was 48.8%, and the optical purity of the obtained (R) -1-benzyloxy-2-propanol was 93.0%.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-103691 (JP, A) JP-A-58-126792 (JP, A) JP-A-61-5975 (JP, A) JP-A-60-1985 224494 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C12P 41/00 BIOSIS (DIALOG)

Claims (1)

(57) [Claims] The present invention relates to the genus Corynebacterium or the genus Micrococcus, and when acted on a mixture of R-form and S-form of 1-benzyloxy-2-acetoxyalkane, the R-form is selectively hydrolyzed. R-form 1-benzyloxy-2
-A culture solution, cells or treated cells of a microorganism having the ability to produce alkanol,
A process for producing an optically active 1-benzyloxy-2-alkanol, which comprises reacting a mixture of R-form and S-form of 2-acetoxyalkane and collecting the generated R-form 1-benzyloxy-2-alkanol. .