Chiral inositol crystal form and preparation method thereof

Abstract

The invention relates to the technical field of chiral inositol, in particular to a chiral inositol crystal form and a preparation method of the chiral inositol crystal form. The crystal form has characteristic diffraction peaks at diffraction angles 2theta of 13.44 + / -0.02 degrees, 14.85 + / -0.02 degrees, 16.58 + / -0.02 degrees, 17.75 + / -0.02 degrees, 19.43 + / -0.02 degrees, 22.79 + / -0.02 degrees, 23.70 + / -0.02 degrees, 24.79 + / -0.02 degrees, 25.90 + / -0.02 degrees, 27.05 + / -0.02 degrees, 28.66 + / -0.02 degrees, 30.11 + / -0.02 degrees, 30.77 + / -0.02 degrees, 34.66 + / -0.02 degrees, 37.776 + / -0.02 degrees, 39.46 + / -0.02 degrees, 40.73 + / -0.02 degrees, 44.78 + / -0.02 degrees and 46.52 + / -0.02 degrees, so that the crystal form has high thermal stability and

Description

Technical Field

[0001] The present invention relates to the technical field of chiral inositol, in particular to a chiral inositol crystal form and a preparation method thereof. Background Art

[0002] Chiro-inositol (Chiro-inositol) is a class of biologically important inositol stereoisomers, primarily including D-chiro-inositol (DCI) and L-chiro-inositol (LCI). DCI and LCI play key roles in metabolic regulation. Currently, numerous methods for the preparation and crystallization of DCI exist. For example, a Chinese patent application (publication number CN117164434A) discloses a crystallization method for D-chiro-inositol. This method utilizes cation- and anion-exchange resins for desalination, followed by concentration and decolorization using a macroporous decolorizing resin and nanofiltration membrane. Combined with stepwise cooling and controlled stirring speed, high-purity D-chiro-inositol is finally obtained through ethanol washing and vacuum drying. However, the crystallization method is complex and not easily adaptable for large-scale industrialization. Furthermore, the stability of existing DCI needs to be further improved, while LCI is subject to the risk of crystal transformation. Therefore, developing a new, more stable crystal form of chiro-inositol is of great practical significance. Summary of the Invention

[0003] To address the above problems, the present invention provides a chiral inositol crystal form. By optimizing the crystallization process conditions, a more stable new chiral inositol crystal form is provided. The new chiral inositol crystal form contains both DCI and LCI, and has a thermal decomposition temperature of 395.81°C. This overcomes the low thermal decomposition temperature of single DCI / LCI, has relatively higher thermal stability, and is suitable for a wider range of applications.

[0004] On the one hand, the present invention provides a chiral inositol crystal form, wherein the chiral inositol crystal form is analyzed by X-ray powder diffraction using Cu-Kα rays, and the diffraction angles 2θ are 13.44±0.02°, 14.85±0.02°, 16.58±0.02°, 17.75±0.02°, 19.43±0.02°, 22.79±0.02°, 23.70±0.02°, 24.79± There are characteristic diffraction peaks at 0.02°, 25.90±0.02°, 27.05±0.02°, 28.66±0.02°, 30.11±0.02°, 30.77±0.02°, 34.66±0.02°, 37.776±0.02°, 39.46±0.02°, 40.73±0.02°, 44.78±0.02° and 46.52±0.02°.

[0005] Furthermore, the chiral inositol crystal form provided by the present invention has the following characteristics: Figure 1The X-ray powder diffraction (XRD) pattern is shown.

[0006] Furthermore, the chiral inositol crystal form provided by the present invention has the following characteristics: Figure 2 The X-ray test results are shown in the figure.

[0007] Furthermore, the crystallographic parameters of the chiral inositol crystal form are shown in Table 1.

[0008] Table 1

[0009] Further, the chiral inositol crystal form has the following Figure 3 The thermogravimetric analysis spectrum shown in the figure shows a weight loss of 95.90% at 250-450°C and the onset of decomposition at 395.81°C.

[0010] Further, the chiral inositol crystal form has the following Figure 4 The differential scanning calorimetry spectrum shown has no characteristic endothermic peak in the range of 0 to 140°C.

[0011] Further, the chiral inositol crystal form has the following Figure 5 The infrared spectrum shown is at 3417 cm -1 、3358cm -1 (hydroxyl), 2967 cm -1 、2924 cm -1 (saturated hydrocarbons), 1420–1000 cm -1 There is a characteristic peak at (methine).

[0012] Further, the chiral inositol crystal form has the following Figure 6 shown 1 H-NMR spectrum, showing chemical shifts of H protons of chiro-inositol at 3.90 ppm, 3.63 ppm, and 3.45 ppm.

[0013] Further, the chiral inositol crystal form has the following Figure 7 shown 13 C-NMR spectrum, in which chemical shifts of the C protons of chiro-inositol are present at 72.7 ppm, 71.6 ppm, and 70.4 ppm.

[0014] Another aspect of the present invention provides a method for preparing a chiral inositol crystal form, which comprises at least the following steps: mixing a chiral inositol sample with an acetonitrile aqueous solution and then allowing the mixture to stand to obtain a chiral inositol crystal form.

[0015] In one embodiment, the volume ratio of acetonitrile to water in the acetonitrile aqueous solution is (3.5-4.5):1.

[0016] In one embodiment, the standing temperature is 20-30° C. and the standing time is 5-10 days.

[0017] In one embodiment, the ratio of the mass of the chiro-inositol sample to the volume of the acetonitrile aqueous solution is (3-5 mg):1 mL.

[0018] In one embodiment, the method for preparing the chiral inositol crystal form comprises the following steps: adding a chiral inositol sample and an acetonitrile aqueous solution into a reagent bottle and shaking to dissolve; sealing the reagent bottle with a sealing film, and punching a hole in the film as a solvent volatilization port; and allowing the sample to stand to obtain the chiral inositol crystal form.

[0019] In one embodiment, the puncture density is 1-2 per cm 2 .

[0020] In one embodiment, the chiro-inositol sample comprises D-chiro-inositol and L-chiro-inositol, and the chiro-inositol sample is sourced from Shandong Zhucheng Haotian Pharmaceutical Co., Ltd.

[0021] Different crystal forms may lead to differences in color, morphology, stability, hygroscopicity and solubility, which in turn affect the subsequent application effects. The thermal decomposition temperatures of existing D-chiro-inositol and L-chiro-inositol are generally low and cannot meet the application requirements of high-temperature processing scenarios. The present invention specifically provides a method comprising Figure 2 The new crystal form of the chiral isomer shown has crystallographic parameters that are clearly different from D-chiro-inositol and L-chiro-inositol, and has a relatively higher thermal decomposition temperature, which can meet the application requirements of high-temperature processing scenarios.

[0022] The chiral inositol crystalline form provided by the present invention effectively overcomes the problems of stability complementation of single DCI and high hygroscopicity of single LCI, increases the flexibility of dosage form design, and has excellent biological necessity, clinical superiority and development economy (reduced dosage requirements).

[0023] However, during the development of the new crystalline form, the present inventors attempted various methods but were unable to obtain a new crystalline form containing both D-chiro-inositol and L-chiro-inositol. Because the chiro-inositol sample contained D-chiro-inositol and L-chiro-inositol, which differ in water solubility and hygroscopicity, and D-chiro-inositol readily forms solvates (such as hydrates and acetonides), the present inventors unexpectedly discovered that dissolving the chiro-inositol sample containing both D-chiro-inositol and L-chiro-inositol in an acetonitrile-water solution, specifically controlling the volume ratio of acetonitrile to water in the acetonitrile-water solution to 3.5-4.5:1 and allowing the solution to stand for five days at 20-30°C, could yield a chiro-inositol crystalline form with excellent thermal stability, avoiding solvate formation. However, using other solvents or acetonitrile-water solutions with a volume ratio of acetonitrile to water outside this range prevented the new crystalline form from being obtained by simple evaporation of the solution.

[0024] Compared with traditional chemical synthesis methods (such as recrystallization), the preparation method of the chiral inositol crystal provided by the present invention obtains a product with excellent performance based on a simple static process by optimizing solvent selection. It does not require complex instruments and equipment, is simple to operate, and greatly reduces production costs.

[0025] Beneficial effects 1. The present invention provides a chiral inositol crystal form. By optimizing the crystallization process conditions, a more stable new chiral inositol crystal form is provided. The new chiral inositol crystal form contains both DCI and LCI, and has a thermal decomposition temperature of 395.81°C. This overcomes the problem of low thermal decomposition temperature of single DCI / LCI, has relatively higher thermal stability, and is suitable for a wider range of applications.

[0026] 2. The present invention specifically provides a method comprising Figure 2 The new crystal form of the chiral isomer shown has crystallographic parameters that are clearly different from D-chiro-inositol and L-chiro-inositol, and has a relatively higher thermal decomposition temperature, which can meet the application requirements of high-temperature processing scenarios.

[0027] 3. The chiral inositol crystalline form provided by the present invention effectively overcomes the problems of stability complementation of single DCI and high hygroscopicity of single LCI, increases the flexibility of dosage form design, and has excellent biological necessity, clinical superiority and development economy (reduced dosage requirements).

[0028] 4. The present invention uses an acetonitrile aqueous solution to dissolve a chiro-inositol sample containing D-chiro-inositol and L-chiro-inositol, especially controlling the volume ratio of acetonitrile to water in the acetonitrile aqueous solution to (3.5-4.5):1, and allowing the solution to stand at 20-30°C for 5 days to obtain a chiro-inositol crystal form with excellent thermal stability, avoiding the formation of solvates.

[0029] 5. Compared with traditional chemical synthesis methods (such as recrystallization), the present invention obtains products with excellent performance based on a simple static process by optimizing solvent selection. It does not require complex instruments and devices, is simple to operate, and greatly reduces production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the XRD pattern of the chiral inositol crystal form provided in Example 1 of the present invention.

[0031] Figure 2 This is an X-ray test result diagram of the chiral inositol crystal form provided in Example 1 of the present invention.

[0032] Figure 3 This is a thermogravimetric analysis diagram of the chiral inositol crystal form provided in Example 1 of the present invention.

[0033] Figure 4 This is the differential scanning calorimetry spectrum of the chiral inositol crystal form provided in Example 1 of the present invention.

[0034] Figure 5 This is the infrared spectrum of the chiral inositol crystal form provided in Example 1 of the present invention.

[0035] Figure 6 The chiral inositol crystal form provided in Example 1 of the present invention is 1 H-NMR spectrum.

[0036] Figure 7 The chiral inositol crystal form provided in Example 1 of the present invention is 13 C-NMR spectrum.

[0037] Figure 8 This is a physical picture of the chiral inositol sample used in Example 1 of the present invention. DETAILED DESCRIPTION

[0038] Example 1 Example 1 of the present invention provides a chiral inositol crystal form, wherein the chiral inositol crystal form is analyzed by X-ray powder diffraction using Cu-Kα rays, and the diffraction angles 2θ are 13.44±0.02°, 14.85±0.02°, 16.58±0.02°, 17.75±0.02°, 19.43±0.02°, 22.79±0.02°, 23.70±0.02°, 24. There are characteristic diffraction peaks at 79±0.02°, 25.90±0.02°, 27.05±0.02°, 28.66±0.02°, 30.11±0.02°, 30.77±0.02°, 34.66±0.02°, 37.776±0.02°, 39.46±0.02°, 40.73±0.02°, 44.78±0.02° and 46.52±0.02°.

[0039] The X-ray powder diffraction analysis was performed using a Bruker D8advance diffractometer from Bruker Instruments GmbH, Germany, using Cu-K radiation at a voltage of 40 kV, a current of 40 mA, a step size of 0.02 degrees, and a time of 0.1 second per step.

[0040] The chiro-inositol crystal form has the following Figure 1 The X-ray powder diffraction (XRD) pattern is shown.

[0041] The chiral inositol crystal form has the following characteristics: Figure 2 The X-ray test results are shown in the figure.

[0042] The crystallographic parameters of the chiral inositol crystal form are shown in Table 1.

[0043] Table 1

[0044] The chiral inositol crystal form has the following characteristics: Figure 3 The thermogravimetric analysis shown shows a weight loss of 95.90% between 250°C and 450°C, with decomposition beginning at 395.81°C. The thermogravimetric analyzer, TG20F3, from NETZSCH Scientific Instruments GmbH, Germany, was used, with a nitrogen atmosphere and a heating rate of 10°C / min.

[0045] The chiro-inositol crystal form has the following Figure 4 The differential scanning calorimetry spectrum shown shows no characteristic endothermic peak in the range of 0-140° C. The measurement was performed using a DSC 8500 differential scanning calorimeter from PerkinElmer, USA, under a nitrogen atmosphere and a heating rate of 10° C. / min.

[0046] The chiral inositol crystal form has the following characteristics: Figure 5 The infrared spectrum shown is at 3417 cm -1 、3358 cm -1 (hydroxyl group), 2967 cm -1 、2924 cm -1 (saturated hydrocarbons), 1420–1000 cm -1 The characteristic peak is at the methine. The infrared spectrometer Nicolet-Magna FT-IR 750 from Nicolet-Magna, USA, was used for detection at 25±2℃, with the detection range of 4000-350cm -1 wave number.

[0047] The chiral inositol crystal form has the following characteristics: Figure 6 shown 1H-NMR spectrum, showing chemical shifts of the H protons of chiro-inositol at 3.90 ppm, 3.63 ppm, and 3.45 ppm. Detection was performed using a Bruker AVANCE III HD 400M NMR instrument (H pulse sequence: zg30, TD (data points): 65 K, RG (gain): 32, D1 (relaxation time): 10 s, SW (spectral width): 20 ppm, O1p (spectral width center): 6.175 ppm, NS (number of scans): 16, DS (number of empty scans): 2).

[0048] The chiral inositol crystal form has the following characteristics: Figure 7 shown 13 C-NMR spectrum, in which chemical shifts of the C protons of chiro-inositol are present at 72.7 ppm, 71.6 ppm, and 70.4 ppm.

[0049] On the other hand, Example 1 of the present invention provides a method for preparing a chiral inositol crystal form, comprising the following steps: adding a chiral inositol sample and an acetonitrile aqueous solution into a reagent bottle and shaking to dissolve; sealing the reagent bottle with a sealing film, and punching a hole in the film as a solvent volatilization port; and allowing to stand to obtain a chiral inositol crystal form.

[0050] The volume ratio of acetonitrile to water in the acetonitrile aqueous solution is 4:1.

[0051] The temperature of the standing state is 25° C. and the time is 5 days.

[0052] The ratio of the mass of the chiro-inositol sample to the volume of the acetonitrile aqueous solution is 4 mg:1 mL.

[0053] The puncture density is 1 per cm 2 .

[0054] See also Figure 8 The chiro-inositol sample contains D-chiro-inositol and L-chiro-inositol, and the chiro-inositol sample comes from Shandong Zhucheng Haotian Pharmaceutical Co., Ltd.

[0055] Example 2 Example 2 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 10:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0056] Example 3 Example 3 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 8:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0057] Example 4 Example 4 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 7:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0058] Example 5 Example 5 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 6:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0059] Example 6 Example 6 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 5:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0060] Example 7 Example 7 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 9:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0061] Example 8 Example 8 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 3:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0062] Example 9 Example 9 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 2:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0063] Example 10 Example 10 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the volume ratio of acetonitrile and water in the acetonitrile aqueous solution is 1:1, and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0064] Example 11 Example 11 of the present invention provides a method for preparing a chiral inositol crystal form. The specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced with acetonitrile (purity 95.5%), and the chiral inositol crystal form cannot be obtained by standing at 25°C for 5 days.

[0065] Example 12 Example 12 of the present invention provides a method for preparing a chiral inositol crystal form. Its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced with methanol (purity 95.5%), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0066] Example 13 Example 13 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 10:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0067] Example 14 Example 14 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 9:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0068] Example 15 Example 15 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 8:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0069] Example 16 Example 16 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 7:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0070] Example 17 Example 17 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 6:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0071] Example 18 Example 18 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 5:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0072] Example 19 Example 19 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 4:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0073] Example 20 Example 20 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 3:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0074] Example 21 Example 21 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol to water in the methanol aqueous solution is 2:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0075] Example 22 Example 22 of the present invention provides a method for preparing a chiral inositol crystal form, and its specific implementation method is the same as that of Example 1, except that the acetonitrile aqueous solution is replaced by a methanol aqueous solution (the volume ratio of methanol and water in the methanol aqueous solution is 1:1), and the chiral inositol crystal form cannot be obtained after standing for 5 days at 25°C.

[0076] Performance Testing 1. The hygroscopicity of the chiro-inositol crystal form and the amorphous sample provided in Example 1 of the present invention were tested. The results are shown in Table 2.

[0077] Table 2

[0078] Analysis of the data in Table 2 shows that at 25° C. and different humidity levels, the hygroscopicity of the chiral inositol crystal form provided in Example 1 of the present invention is significantly lower than that of the amorphous sample. When stored under the same conditions, the chiral inositol crystal form provided in Example 1 of the present invention has a better appearance, good fluidity, no caking phenomenon, and good physical stability.

[0079] 2. The solubility of the chiro-inositol crystalline form and the amorphous sample provided in Example 1 of the present invention was tested at different temperatures (the mass of the different crystalline chiro-inositol forms dissolved in 100 mL of water at different temperatures, and kept at each temperature for 10 minutes until it did not dissolve). The results are shown in Table 3.

[0080] Table 3

[0081] Analysis of the data in Table 3 shows that the chiral inositol crystal form provided in Example 1 of the present invention has better solubility than the amorphous sample.

Claims

1. A chiral inositol crystal form, characterized in that: The X-ray powder diffraction analysis of the chiral inositol crystal form measured by Cu-Kα ray showed that the diffraction angles 2θ were 13.44±0.02°, 14.85±0.02°, 16.58±0.02°, 17.75±0.02°, 19.43±0.02°, 22.79±0.02°, 23.70±0.02°, 24.79±0.02°, 25. There are characteristic diffraction peaks at 90±0.02°, 27.05±0.02°, 28.66±0.02°, 30.11±0.02°, 30.77±0.02°, 34.66±0.02°, 37.776±0.02°, 39.46±0.02°, 40.73±0.02°, 44.78±0.02° and 46.52±0.02°.

2. The chiral inositol crystal form according to claim 1, wherein The chiro-inositol crystal form loses 95.90% of its weight at 250-450° C. and begins to decompose at 395.81° C.

3. The chiral inositol crystal form according to claim 1, wherein The differential scanning calorimetry spectrum of the chiral inositol crystal form has no characteristic endothermic peak in the range of 0 to 140°C.

4. The chiral inositol crystal form according to claim 1, characterized in that The infrared spectrum of the chiral inositol crystal form is at 3417 cm -1 、3358 cm -1 、2967 cm -1 、2924 cm -1 and 1420-1000 cm -1 There is a characteristic peak.

5. The chiral inositol crystal form according to claim 1, characterized in that The chiral inositol crystal form 1 In the H-NMR spectrum, chemical shifts of the H protons of chiro-inositol are present at 3.90 ppm, 3.63 ppm, and 3.45 ppm.

6. The chiral inositol crystal form according to claim 1, characterized in that The chiral inositol crystal form 13 In the C-NMR spectrum, chemical shifts of the C protons of chiro-inositol are present at 72.7 ppm, 71.6 ppm, and 70.4 ppm.

7. A method for preparing a chiral inositol crystal form according to any one of claims 1 to 6, characterized in that: At least the following steps are included: The chiral inositol sample is mixed with an acetonitrile aqueous solution and then allowed to stand to obtain a chiral inositol crystal form.

8. The method for preparing the chiral inositol crystal form according to claim 7, wherein The volume ratio of acetonitrile to water in the acetonitrile aqueous solution is (3.5-4.5):

1.

9. The method for preparing the chiral inositol crystal form according to claim 7, wherein The temperature of the standing state is 20-30° C., and the time is 5-10 days.

10. The method for preparing the chiral inositol crystal form according to claim 7, wherein The ratio of the mass of the chiro-inositol sample to the volume of the acetonitrile aqueous solution is (3-5 mg):1 mL.

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