JPH0820550A - Production of chiro-inositol - Google Patents

Abstract

PURPOSE:To provide a process for an industrially simple and high-yield production of D-chiro-inositol of high purity through hydrolysis of Kasugamycin under mild and acidic conditions. CONSTITUTION:An aqueous solution of a salt or base-free kasugamycin is mixed with granules of strongly acidic ion-exchange resin (H<+> type heated under normal or elevated pressure to effect hydrolysis of Kasugamycin and obtain an acidic reaction mixture solution containing D-chiro-inositol. After completion of the reaction, the acidic solution is separated from the resin and D-chiro- inositol is recovered from the reaction solution. In the recovery of the compound, the acidic solution is passed through an acidic ion-exchange resin H<+> type column and a basic ion-exchange resin (OH<-> type) column in order to give a neutral eluate containing D-chiro-inositol. Then, the eluate is concentrated to crystallize out D-chiro-inositol whereby purified D-chiro-inositol is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved method for producing D-chiro-inositol (hereinafter sometimes simply referred to as "DCI"). DCI has recently attracted attention as a therapeutic or prophylactic agent for non-insulin-dependent diabetes mellitus.

[0002]

2. Description of the Related Art Up to now, the following methods have been known as a method for producing DCI. Pinitol contained in plants such as bougainvillea, sugar pine and American cedar;
DCI monomethyl ether body) is extracted and demethylated with hydroiodic acid or the like to obtain DCI.

1-chloro-2,3-dihydroxyc
yclohexa-4,6-diene) as a starting material to obtain DCI through several steps of reaction [J. Org. Chem.
Of Organic Chemistry), Vol. 58, No. 23
31 to 2333, 1993].

A method of obtaining DCI through halogenobenzene as a starting material through several steps of reaction [J. Chem. Soc. Perk
in Transactions 1 (Journal of the Chemical
Society Perkin Transactions), No. 741
P.-743, 1993]. By using high-purity kasugamycin as a raw material and heating it in 2N trifluoroacetic acid or 5N hydrochloric acid, hydrolysis was carried out under a very strong acidic condition, and then the obtained reaction solution was neutralized and subjected to impurities. For the purpose of removing DCI, it is passed through a column of a basic ion exchange resin and a column of a strongly acidic ion exchange resin sequentially or through a column in which these resins are mixed, and DCI is obtained by recrystallizing with ethanol from the column passage liquid. How to obtain (US Pat. No. 5,091,5
96 specification).

[0005]

Although various methods of producing DCI have been proposed as described above, there are various difficulties in producing DCI advantageously on an industrial scale. That is, DCI extracted from a plant by the method
In the method of (1), the separation and purification of DCI are complicated and the yield is low. In addition, the method for producing DCI by chemical synthesis with and requires a stereospecific synthesis, resulting in a low reaction yield,
Manufacturing costs are also high.

In the acid hydrolysis reaction of kasugamycin by the above method, since a very strong acid (5N hydrochloric acid or 2N trifluoroacetic acid aqueous solution) is used, impurities are generated by a side reaction when the kasugamycin molecule is cleaved. Unavoidable. In particular, as a side reaction of decomposing an amino sugar, which is another constituent sugar of kasugamycin, impurities are generated and the yield of DCI becomes poor. In the method, a large amount of strong basic ion exchange resin is used to neutralize the strong acid used for hydrolysis, and a large amount of strong acidic ion exchange resin is also used to remove by-produced basic compounds. In order to use (each resin uses about 13 times the amount of kasugamycin by weight), a large amount of reagents and a large amount of water are required for the regeneration of these ion exchange resins after use, and a large amount of waste water is required. There are many problems such as the need for post-processing.

Therefore, it is desired to develop an industrially advantageous method for producing DCI, which is an alternative to these known production methods. Under such circumstances, an object of the present invention is to provide a method capable of producing DCI with high purity and high yield by a simple operation.

[0008]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems. As a result, when hydrolyzing the hydrochloride, sulfate or free base of kasugamycin (hereinafter, unless otherwise specified, these salts and free base are simply referred to as "kasugamycin"),
In a batch-type reaction container, that is, by reacting the strongly acidic ion-exchange resin granules and an aqueous solution of kasugamycin under heating conditions, the reaction is performed to hydrolyze kasugamycin to produce DCI, and the reaction containing the produced DCI After obtaining a solution and passing it through a column of strongly acidic ion exchange resin, a step of passing it through a strongly basic ion exchange resin column to obtain a neutral eluate containing DCI and then crystallizing DCI is performed. Therefore, it was found that high-purity DCI crystals can be obtained. As a result, the first aspect of the present invention has been achieved.

That is, the gist of the first aspect of the present invention is a method for producing D-kilo-inositol, which is characterized in that the following first to fourth steps are continuously performed.

(Step 1): Hydrolysis of kasugamycin by mixing an aqueous solution of kasugamycin salt or free base with granules of strongly acidic ion exchange resin (H ⁺ type) and heating this mixture under normal pressure or under pressure. And a step of separating the produced acidic reaction solution containing D-kilo-inositol from the resin after completion of the reaction to obtain an acidic reaction solution containing D-kilo-inositol. (Second step): The acidic reaction solution obtained in the first step is passed through a column packed with a strongly acidic ion exchange resin (H ⁺ type) to remove the basic impurities present in the reaction solution. In addition, a step of removing unreacted kasugamycin that may possibly be present to obtain an acidic aqueous solution containing DCI. (Third step): The acidic aqueous solution obtained in the second step is passed through a column packed with a strongly basic ion exchange resin (OH ⁻ type) to form DC.
Obtaining a neutralized eluate containing I. (Fourth step): a step of concentrating the eluate obtained in the third step and precipitating high-purity DCI crystals from the concentrated solution.

In addition, using kasugamycin as a raw material and mixing with a strongly acidic ion exchange resin (H ⁺ type) in the same manner as in the first step of the method of the first aspect of the present invention, kasugamycin is hydrolyzed under heating to give DCI. When an acidic reaction solution containing is obtained,
It has been found that DCI can be recovered from this reaction solution by the application of generally conventional recovery methods for neutral sugars.

Therefore, the gist of the second aspect of the present invention is to mix an aqueous solution of kasugamycin salt or a free base with a granular material of a strongly acidic ion exchange resin (H ⁺ type) and to mix the mixture under normal pressure or under pressure. After the reaction was completed, the kasugamycin was hydrolyzed, and after the reaction was completed, the produced D-kilo-
Separating the acidic reaction solution containing inositol from the strongly acidic ion exchange resin used to obtain an acidic reaction solution containing D-kilo-inositol, and further recovering D-kilo-inositol from this acidic reaction solution. And a method for producing D-kilo-inositol.

The aqueous solution of kasugamycin free base, hydrochloride or sulfate used as a starting material in the first and second methods of the present invention is usually prepared and used as follows. That is, the kasugamycin-producing bacterium improved so as to increase the production titer is cultured by a usual method, and the obtained culture solution is filtered. Then, kasugamycin free base, hydrochloride or sulfate is separated from the culture filtrate by a usual collecting method.

The high-purity kasugamycin free base, hydrochloride or sulfate thus obtained is preferably pretreated in several purification steps before use. Further, when using high-purity kasugamycin hydrochloride or sulfate, for example, as a kasugamycin hydrochloride or sulfate raw material powder produced in Japan or abroad as a kasugamycin raw material for the production of pesticides for controlling plant diseases is used. At this time, the highly pure product may be dissolved in ion-exchanged water or the like and used as it is. However, if the purity is low,
It is preferable to dissolve it in ion-exchanged water or the like, and then preliminarily purify it through a column containing activated carbon before use.

The outline of the two manufacturing methods according to the first and second aspects of the present invention will be described below. I) First Inventive Method The first inventive method is roughly composed of four steps. Each step will be described in detail below.

(1) Method for carrying out the first step In the first step of the method of the first aspect of the present invention, a batch-type reaction vessel is used, and kasugamycin is added to the strongly acidic ion exchange resin (H ⁺ type) in the reaction vessel. When the mixture is mixed with the granules and heated under atmospheric pressure or pressure in the presence of the resin, kasugamycin is hydrolyzed to form DCI. The reaction mixture may be stirred during the reaction or may be left standing.

The strongly acidic ion exchange resin (H ⁺ type) used in the first step is preferably an ion exchange resin having a sulfonic acid residue, and as an example thereof, a commercially available strongly acidic ion exchange resin such as DIAION (registered) is registered. Trademark) SK116,
Diaion (registered trademark) PK228, Amberlite (registered trademark) IR120B, Amberlite (registered trademark) 200C, Amberlite (registered trademark) 201B,
Duolite (registered trademark) C-20, Duolite (registered trademark) C-264, Duolite (registered trademark) XE-
636, Dowex (registered trademark) 50W, and the like.

The concentration of kasugamycin in the aqueous solution of kasugamycin used may be 0.1 to 30% by weight, preferably 10 to 25%. In this case, if kasugamycin is used as an aqueous solution prepared by heating it to a temperature as high as possible (10 to 25% by weight) if necessary by heating it to about 60 to 80 ° C., DCI purification operation after the hydrolysis step (particularly aqueous solution) (Concentrating operation) can be easily performed. The amount of the strongly acidic ion exchange resin (H ⁺ type) is preferably at least 1 time the ion exchange capacity with respect to the amount of kasugamycin.

Increases the hydrolysis rate of kasugamycin, DC
In order to obtain I in a high yield, it is better that the reaction temperature is high (for example, the boiling point of water is near 100 ° C.) and the reaction time is long.

However, in order to repeatedly use the strongly acidic ion exchange resin to be used after it is regenerated, the durable temperature of the strongly acidic ion exchange resin to be used (for example, DIAION (registered trademark))
The service temperature of SK116 is 120 ° C, and that of Duolite (registered trademark) CC-240F is 135 ° C).

The reaction temperature and reaction time for hydrolysis vary depending on the type of strongly acidic ion exchange resin used, but when using, for example, Diaion (registered trademark) SK116, the temperature is 50 to 100 ° C. under normal pressure, preferably 90-98 ° C
And the reaction time is 6 to 60 hours, preferably 10 to 4
8 hours. When the reaction mixture is left standing or reacted under stirring under such conditions, kasugamycin is hydrolyzed by almost 100% and converted to DCI.

Further, the hydrolysis of kasugamycin is carried out by using a strongly acidic ion exchange resin (H ⁺ type) similar to that described above and under a pressure sufficient to suppress boiling of water in the reaction mixture, for example, a gauge pressure. At 0.1 to 3 kg / cm ² pressure, preferably 0.5 to 1.2 kg / cm ² at a temperature of 110 to 120 ° C., for example, 1 to 12 hours, preferably 1 to 6
The hydrolysis reaction can be completed in a time, and DCI can be produced in the reaction solution in a yield close to 100% of the theoretical yield.

When the hydrolysis reaction of kasugamycin is carried out under pressure as described above, it is preferable that the reaction container has a pressure resistant structure or the reaction container is installed in an autoclave. Further, when carrying out the hydrolysis reaction, it is not always necessary to stir the reaction mixture.

After the hydrolysis reaction of kasugamycin is completed, if necessary, the mixture of the resin and the acidic reaction solution is cooled to a temperature lower than 50 ° C., preferably room temperature. The acidic reaction solution can be separated from the strongly acidic ion exchange resin by filtration. The acidity of the acidic reaction solution obtained as the filtrate varies depending on the amount and type of kasugamycin or the strongly acidic ion exchange resin used, but corresponds to about 0.05 to 1.0 N. The resin obtained as the filtration residue is 0.8-1 of the resin.
When double the amount of water is added to the resin for washing, DCI is eluted in water to obtain a washing solution containing DCI. Then, this washing solution is mixed with the acidic reaction solution obtained by filtering above.

(2) Method for carrying out the second step In the second step of the first method of the present invention, the DC obtained in the first step is used.
The acidic reaction solution containing I is passed through a strongly acidic ion exchange resin column for purification purposes. Then, unreacted kasugamycin, the basic substance that could not be adsorbed on the resin in the first step, and the basic substance by-produced in the first step can be removed.

The strongly acidic ion exchange resin used here is
The same kind as that used in the first step, for example, Diaion (registered trademark) SK116 or the like, is used in the same manner as in the first step (H ⁺ type).
It may be used by filling the column. In this case, the amount of the resin packed in the column varies depending on the amount of the basic component to be removed contained in the acidic reaction solution obtained in the first step, but in the usual case, the amount of the resin used in the first step Approximately the same amount of strongly acidic ion exchange resin may be used.

The acidic reaction solution obtained by passing through the column in this second step can be used as it is in the third step. However, the residual D in the strongly acidic ion exchange resin used
In order to elute CI, the resin is washed by adding approximately the same amount of ion-exchanged water to the column top as it is, or by washing the resin by adding ion-exchanged water to the column top and then stirring the resin. This water washing solution may be combined with the above acidic reaction solution. If the combined solution is used in the next third step, DCI can be obtained in a higher yield.

(3) Method of Carrying Out Third Step The third step of the first method of the present invention is carried out for the purpose of neutralizing the acid generated in the hydrolysis reaction of the first step. As the neutralizing method, the acidic aqueous solution containing DCI obtained in the second step is passed through a column packed with a strongly basic ion exchange resin,
This gives a neutral eluate containing DCI.

The strongly basic ion exchange resin (OH ^- type) used here is an ion exchange resin containing a quaternary ammonium group as a functional group, such as Duolite (registered trademark) A-113PLUS and Amberlite ( Registered trademark) IRA 410 and the like. The amount of the basic ion exchange resin packed in the column varies depending on the amount of the acidic component to be removed contained in the reaction solution to be treated in the second step, but usually the resin used in the first step By using the amount of the strongly basic ion exchange resin in the range from the equivalent amount to the double amount, the acidic component in the DCI aqueous solution can be adsorbed and the aqueous solution can be neutralized.

The neutralized DCI aqueous solution thus obtained as the column eluate may be used as it is in the fourth step. However, as in the second step, the resin used in the third step is washed with ion-exchanged water and the washing solution is washed with DCI.
When combined with the aqueous solution and subjected to the fourth step, DCI can be obtained in a higher yield. When the DCI-containing eluate neutralized in the third step is desired to be further purified, it may be passed through a column packed with an adsorbent such as activated carbon.

Impurities contained in kasugamycin used as a raw material by the second and third steps of the first method of the present invention, by-products produced from the impurities by the hydrolysis reaction in the first step, and kasugamycin By-products generated by hydrolysis can be completely removed.
As a result, high-purity DCI can be obtained.

(4) Method for carrying out the fourth step In the fourth step of the first method of the present invention, the neutral eluate containing the DCI obtained in the third step and containing substantially no impurities is used. Collect DCI. For this recovery, the eluate may be concentrated to crystallize DCI. For example, in order to concentrate the eluate, it is heated in a rotary evaporator under reduced pressure. 60 to 8 of the concentrated liquid thus obtained
Heat to about 0 ° C. For this heated concentrate,
Ethanol heated to the same temperature is added with stirring.
Thereafter, when the temperature is returned to room temperature, DCI gradually crystallizes. After the crystals are separated, the crystals are filtered off with a glass filter and dried to obtain the desired white crystals of DCI. In this case, the crystals are dried under reduced pressure at 50 to 120 ° C., preferably 90 to 120 ° C.
Drying at 110 ° C. for 2 to 5 hours gives white crystals of DCI in a short time.

In the present invention, DCI purified to a purity of almost 100% can be obtained by continuously performing the first to fourth steps.

II) Second Method of the Present Invention In the second method of the present invention, an aqueous solution of kasugamycin is mixed with granules of a strongly acidic ion exchange resin (H ⁺ type), and the mixture is subjected to normal pressure or pressure. To hydrolyze kasugamycin, and after the reaction is completed, the acidic reaction solution containing DCI is separated from the resin to obtain an acidic reaction solution,
Further, it is a method for producing DCI, which is characterized in that DCI is recovered from the acidic reaction solution.

In this second method of the present invention, the steps of mixing an aqueous solution of kasugamycin with a strongly acidic ion-exchange resin for hydrolysis and obtaining an acidic reaction solution containing DCI are the same as those of the first method of the present invention. It can be operated in the same manner as in the first step.

The first step and the second step of the first present invention
In performing the hydrolysis step of kasugamycin of the present invention, by performing batchwise using a column-shaped reaction vessel rather than a tank type, since the subsequent step also uses a resin column, individual steps can be continued or continuous. It is also possible to produce high-purity DCI without taking the reaction solution out of the system of the apparatus used even once.

The size of the column-shaped reaction vessel used for the hydrolysis reaction may be appropriately changed depending on the concentration and amount of the kasugamycin aqueous solution used, but when it is carried out on a small scale, for example, the inner diameter is 5 to 6 cm, and the length is long. A column-shaped reaction vessel having a size of about 4 to 10 cm is used.

A column-shaped reaction vessel having a large inner diameter may be used for stirring and mixing the aqueous solution of kasugamycin and the resin.

Next, the DCI manufacturing method of the present invention will be described with reference to examples, but the examples of the present invention are not limited thereto.

[0040]

EXAMPLE 1 This example illustrates the method of the present invention, which uses an aqueous solution of kasugamycin hydrochloride as a raw material and includes a step of decomposing under pressure at atmospheric pressure.

(First Step) (Hydrolysis Step) Five crystals of kasugamycin hydrochloride (15.5 g, purity 97.1%) were added.
It was weighed in an eggplant-shaped flask having a capacity of 00 ml, and 100 ml of ion-exchanged water was added and dissolved to obtain a kasugamycin-hydrochloric acid aqueous solution. Strong acid ion exchange resin DIAION (registered trademark) SK116 (H ⁺ type) <ion exchange capacity
2.1 meq / ml> 100 ml was added and mixed. The mixture was heated with a magnetic stirrer at 95 ° C. for 12 hours to hydrolyze kasugamycin.

After cooling the reaction mixture to room temperature, the strongly acidic ion exchange resin was filtered off. A portion of this acidic filtrate
Titration with 0.1N sodium hydroxide solution corresponded to 0.7N acid. Further, this resin was washed with 100 ml of ion exchanged water, and the filtrate and the washing liquid (water washing liquid) were combined to obtain 230 ml of an acidic reaction solution (DCI yield 98%).

A portion of the above acidic filtrate, that is, an acidic reaction solution containing DCI produced by hydrolysis, was taken, and silica gel TLC (Merck, Art 5715) (developing solvent: n-
It was subjected to butanol-acetic acid-water, 2: 1: 1), and the silica gel layer was further color-tested with ninhydrin, vanillin-sulfuric acid, potassium permanganate or iodine vapor, respectively, for comparison. According to this, a spot of DCI (Rf = 0.39) was observed in the color development by potassium permanganate and vanillin-sulfuric acid, and a spot of a by-product (R by the color development by ninhydrin, vanillin-sulfuric acid or iodine vapor) was observed.
f = 0.58 was observed). This indicates that only a small amount of by-products other than DCI was generated in the hydrolysis reaction.

(Second Step) (Step of Removing Basic Substance) The acidic reaction solution obtained in the first step was treated with a strongly acidic ion exchange resin, Duolite (registered trademark) C-20 (H ⁺ type, 70).
ml) and the column (inner diameter 2 cm, length 22 cm) was placed on top and passed. After passing the reaction solution, the resin was further washed with 70 ml of ion-exchanged water, and the column passage liquid and the washing liquid obtained above were mixed to obtain 300 ml of the reaction solution.

(Third step) (Neutralization step) About 300 ml of the acidic reaction solution obtained in the second step was mixed with a strongly basic ion exchange resin, Duolite (registered trademark) A-1.
13 PLUS (OH ^- type, 100 ml) was loaded onto the column (inner diameter 2.4 cm, length 22 cm) and passed through. The resin is washed with deionized water and the first 100 ml
The eluate was removed and the next about 200 ml of eluate was collected.
Furthermore, this resin is washed with 100 ml of deionized water,
About 100 ml of this washing liquid was mixed with the column eluate collected previously to obtain about 300 ml of a neutral aqueous solution.

The aqueous solution obtained by the above operation was a neutralized and highly purified DCI solution. D in aqueous solution
When the CI content was measured by high performance liquid chromatography,
It was 5.9 g (theoretical value 6.2 g) (yield 94%, converted purity about 99%).

(Fourth step) (DCI crystallization step) About 300 ml of the aqueous solution obtained in the third step was concentrated to about 25 ml using a rotary evaporator and heated to 70 ° C.
To this concentrated solution, 225 ml of ethanol heated to the same temperature was added with stirring, and the mixture was allowed to stand at room temperature for about 12 hours to crystallize DCI. After the crystals were precipitated, the crystals were filtered off with a glass filter and dried under reduced pressure at 105 ° C. for 4 hours to obtain 5.8 g of DCI white crystals (yield 94%, purity about 100%).

The DCI thus obtained has a specific rotation of [α] _D + 65 ° (c1.0, H ₂ O) and a melting point of 238.
C., and it was shown from these physicochemical properties that this substance was pure.

Example 2 This example illustrates the method of the present invention comprising the use of kasugamycin free base as a raw material and the step of hydrolyzing under normal pressure.

As in the first step of Example-1, 100 parts of an aqueous solution of kasugamycin free base (15 g, purity 98%).
ml is weighed in a 500 ml eggplant-shaped flask and strongly acidic ion exchange resin DIAION (registered trademark) SK116 (H
⁺ Type) (100 ml) was added, and kasugamycin was hydrolyzed by heating at 95 ° C. for 12 hours while stirring. After cooling the whole reaction mixture to room temperature, the strongly acidic ion-exchange resin was filtered off, the resin was washed with 100 ml of ion-exchanged water, and the acidic reaction solution of the filtrate and the washing solution was combined to about 2
30 ml was obtained. When this acidic reaction solution was treated in the same manner as in the operations of the second, third and fourth steps of Example 1, 6.6 g of highly pure DCI (yield 94%, purity 100%) was obtained.

Examples 3 to 11 This example shows a method including the step of hydrolyzing by the method of the present invention using kasugamycin hydrochloride as a raw material.

Kasugamycin hydrochloride crystals 10.0 g (purity 9
9%) as a raw material and various conditions such as the type, amount, reaction temperature and reaction time of the resin used in the hydrolysis step (first step) are changed as shown in Table 1 below, and the same procedure as in Example 1 is followed. DCI is manufactured.

(1) First step (hydrolysis step) Kasugamycin (KSM) hydrochloride crystals 10.0 g, 500 ml
It was weighed in an Erlenmeyer flask having a capacity, dissolved by heating with 50 ml of ion-exchanged water, and a strongly acidic ion-exchange resin (prepared to H ⁺ type) shown in Table 1 below was added and mixed. Then, the hydrolysis reaction was carried out batchwise under normal pressure or under pressure in an autoclave. During the reaction, the reaction mixture was allowed to stand without stirring. Then, the reaction solution was cooled to room temperature, the strongly acidic ion exchange resin was filtered off, and the resin was washed with 50 ml of ion exchange water. About 140 ml of an acidic reaction solution was obtained by mixing the washing solution and the filtrate.

(2) Second to Fourth Steps After the hydrolysis, from the reaction solution to the steps of purifying and recovering DCI (second to fourth steps), under the following conditions (1) to (1), It carried out according to it.

The strongly acidic ion exchange resin used in the second step is 5 of Duolite (registered trademark) C-20 (H ⁺ type).
0 ml was packed into a column (2 x 16 cm) and used. D
The CI elution fraction and 50 ml of the washing solution of the resin are combined to give about 17
5 ml of acidic reaction solution was obtained.

The strongly basic ion exchange resin used in the third step is Duolite (registered trademark) A-113PLUS (O
A 60 ml volume of H ⁻ form was packed into a column (2 × 19 cm) and used. 60 ml of the DCI elution fraction and the washing solution of the resin
Were combined to obtain about 200 ml of a neutralized eluate.

In the fourth step, about 200 ml of the eluate obtained in the third step was concentrated to about 10 ml, heated to about 70 ° C., 70 ml of ethanol heated to the same temperature was added and mixed, and the mixture was allowed to stand at room temperature for about 12 ml. The mixture was allowed to stand for a period of time to precipitate DCI crystals. The precipitated crystals were collected by filtration and dried. And the purity and the yield were investigated.

The experimental results of Examples 3 to 11 above are summarized in Table 1 below. This Table 1 shows the above-mentioned Examples 1 to 1.
2 and the experimental results of the comparative example described later are also described.

[0059]

[Table 1]

In Table 1, * indicates the use of KSM free base and all other uses of KSM hydrochloride ** A indicates Diaion SK116 and B indicates Duolite CC204F *** High performance liquid chromatography Analytical measurements are shown **** Inventive methods 2 and 3 for the purification of DCI
Shows the total amount of the strongly acidic ion exchange resin and the strongly basic ion exchange resin required for the step (P): Shows the total amount of the resin required for treating the reaction solution in the comparative example according to the conventional US patent method.

The reaction mixture of the hydrolysis step was reacted under stirring conditions in Examples 1 and 2, and under standing conditions in Examples 3 to 11 and Comparative Example.

Comparative Example Kasugamycin was hydrolyzed with hydrochloric acid according to the method described in US Pat. No. 5,091,596, and then DCI was purified to produce DCI.

That is, kasugamycin hydrochloride crystal 10.0 g
31 ml of 5N hydrochloric acid was added to (purity 99%) and reacted at 90 ° C. for 8 hours (DCI yield 89%). This reaction solution was applied to silica gel TLC in the same manner as in Example 1 to examine the presence of by-products contained in the reaction solution. A spot indicating the presence of a large amount of by-products was observed near Rf = 0.58, and a spot indicating the presence of a large amount of by-products other than DCI was observed near Rf = 0.39 due to color development by ninhydrin and iodine vapor.

After the reaction, the reaction solution was diluted twice with distilled water (liquid volume about 70 ml). This strongly acidic reaction solution was used as a strongly basic ion exchange resin Amberlite (registered trademark) IRA410.
It was passed through a (OH ⁻ type) column (250 ml, 3 × 35 cm) and then washed with 500 ml of distilled water. When the hydrogen ion concentration of the DCI elution fraction (liquid volume 440 ml, colored deep yellow) was examined by TB test paper, the color tone of the test paper showed dark blue, indicating that the solution was strongly alkaline. This solution was then applied to a column of strongly acidic ion exchange resin Amberlite (registered trademark) IRA120 (H ⁺ type) (250 ml, 3 ×).
35 cm) and then washed with 500 ml of distilled water. When the DCI fraction (500 ml of liquid, colorless and transparent) was examined with TB test paper, the color tone was unchanged and the solution was slightly acidic. Next, 0.76 g of activated carbon was added to the solution, and the mixture was stirred at 5 ° C. for 2 hours. The activated carbon was removed by filtration with filter paper, and the activated carbon was washed with ion-exchanged water. Mixture 52 of filtrate and washing liquid of activated carbon
3.9 g of crude crystals of DCI by concentrating 0 ml to dryness
(Purity of about 92%) was obtained.

Next, 1 part of distilled water was added to 3.9 g of the crude crystals obtained above.
0 ml was added, the mixture was heated to about 70 ° C., 70 ml of ethanol heated to the same temperature was added and mixed, and the mixture was allowed to stand at room temperature for about 12 hours to precipitate DCI crystals. The DCI crystals were collected by filtration and dried to obtain 3.4 g of DCI crystals (yield 82%, purity 100%). The purity of DCI was analyzed by liquid chromatography.

[0066]

Industrial Applicability According to the method of the present invention, D
The method for producing CI is very advantageous in the following points as compared with the conventional method of hydrolyzing kasugamycin with a strong acid aqueous solution.

According to the method of the present invention, DCI with high yield and high purity can be obtained under mild reaction conditions and by a simple operation without side reactions. That is, the method of the present invention uses a strongly acidic ion exchange resin for the hydrolysis of kasugamycin, regardless of the conventional method using a liquid acid, so that the DCI yield in the reaction solution immediately after hydrolysis is 90% or more. Which is 80 in the conventional method.
It is extremely advantageous, while it is in the% range. Such high levels of DCI yields are maintained until the final stage, and 100% pure DCI is obtained in yields significantly higher than 90%. Moreover, by performing hydrolysis of kasugamycin using a strongly acidic ion-exchange resin, the amount of resin in the DCI purification step is significantly smaller than that of the conventional method by about 1/5 to 2/5, so that Concentrated solution volume is also about 2/5 to 3/5
The concentration device is small and the concentration time is short.

When the hydrolysis reaction of kasugamycin is carried out at high temperature and high pressure, the reaction time can be shortened to 1/4 as compared with the reaction under normal pressure.

The strongly acidic or basic ion exchange resin used in the method of the present invention can be reused by regenerating it with an aqueous solution of alkali or acid.

The amount of acid and alkali used for the hydrolysis reaction and regeneration of the strongly acidic or strongly basic ion exchange resin used is about one third of the amount used in the conventional method of decomposing kasugamycin with a strong acid. In addition, the equipment is small, and the labor such as wastewater treatment is greatly reduced.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location // C07B 61/00 300 (72) Inventor Tomio Takeuchi 5-11, Higashigotanda, Shinagawa-ku, Tokyo No. New Fuji Mansion 701

Claims (2)

[Claims] 1. A method for producing D-kilo-inositol, which comprises continuously performing the following first to fourth steps. (First step): An aqueous solution of kasugamycin salt or free base is mixed with a granular material of strongly acidic ion exchange resin (H ⁺ type), and the mixture is heated under normal pressure or under pressure to hydrolyze kasugamycin, After completion of the reaction, D- produced
Separating an acidic reaction solution containing cyl-inositol from the resin to obtain an acidic reaction solution containing D-cyl-inositol. (Second step): The acidic reaction solution obtained in the first step is passed through a column packed with a strongly acidic ion exchange resin (H ⁺ type) to remove the basic impurities present in the reaction solution. And a step of removing unreacted kasugamycin which may optionally be present to obtain an acidic aqueous solution containing D-kilo-inositol. (Third step): The acidic aqueous solution obtained in the second step is passed through a column packed with a strongly basic ion exchange resin (OH ⁻ type) to form D-
Obtaining a neutralized eluate containing chiro-inositol. (Fourth step): a step of concentrating the eluate obtained in the third step and precipitating crystals of D-kilo-inositol from the concentrated solution. 2. An aqueous solution of a kasugamycin salt or a free base is mixed with a granular material of a strongly acidic ion exchange resin (H ⁺ type), and the mixture is heated under normal pressure or under pressure to hydrolyze kasugamycin to react. After completion, the generated D-
It is characterized in that an acidic reaction solution containing cyl-inositol is separated from the resin to obtain an acidic reaction solution containing D-kyl-inositol, and D-kyl-inositol is recovered from the acidic reaction solution. A method for producing D-kilo-inositol.