Lithium valproate and crystal form, preparation method, pharmaceutical composition and application thereof

Abstract

The invention relates to the technical field of medicinal chemistry, in particular to lithium valproate and a crystal form, a preparation method, a pharmaceutical composition and application thereof. The crystal forms of the lithium valproate comprise a crystal form I, a crystal form II, a crystal form III, a crystal form IV, a crystal form V, a crystal form VI and a crystal form VII. The lithium valproate provided by the invention has a more comprehensive treatment effect on nervous system diseases, and is good in curative effect and good in stability.

Description

Technical Field

[0001] The present application relates to the field of medical technology, and in particular to lithium valproate and its crystal form, preparation method, pharmaceutical composition and application. Background Art

[0002] Neurological diseases refer to diseases that occur in the central nervous system, peripheral nervous system, and autonomic nervous system and are characterized by sensory, motor, conscious, and autonomic dysfunction. Neurological diseases may cause epilepsy, mania, mental retardation, bipolar disorder, anxiety, depression, and agitation, resulting in impaired motor and sensory functions, cognitive and psychological disorders, and seriously affecting the patient's normal life.

[0003] Epilepsy is a chronic brain disease characterized by repeated epileptic seizures. It is caused by abnormal discharges of brain neurons, and the onset of the disease is characterized by repetitiveness and transience. Valproic acid is a class of anti-epileptic drugs that has varying degrees of antagonism against convulsions caused by various methods. It is effective for various types of epilepsy in humans, such as various types of petit mal seizures, myoclonic epilepsy, focal seizures, grand mal seizures, and mixed epilepsy. Sodium valproate is a commonly used anti-epileptic drug in clinical practice. Currently, sodium valproate ordinary preparations and sustained-release preparations are under clinical development. The dosage of sodium valproate sustained-release tablets for the treatment of epilepsy or mania is 500 mg / day / portion for adults initially, taken in 2 doses, once in the morning and evening, up to 1500 mg / day in one week, and the maintenance dose is 1000 mg-2000 mg / day, which means that patients will also ingest excessive sodium content when taking sodium valproate sustained-release tablets.

[0004] Depression, also known as depressive disorder, is a mental disorder with high incidence, high clinical cure rate, low treatment acceptance rate and high recurrence rate. Its main feature is significant and persistent low mood. Patients may have self-harm and suicidal behaviors, accompanied by psychotic symptoms such as delusions and hallucinations. Drug treatment for depression is the main treatment method. At present, the mainstream antidepressants in clinical practice are mainly a class of selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs). These drugs generally take effect within 2 to 4 weeks. Due to the slow effect, for depressed patients, especially severe patients, adverse reactions appear before the efficacy appears. Patients often refuse to take medication within 1 to 2 weeks, and even commit suicide during this period. This has become a clinical pain point for antidepressant treatment.

[0005] Agitation is a common acute syndrome in psychiatry. It is a comorbid feature of many neurological diseases including schizophrenia, anxiety, depression, dementia and Alzheimer's disease. It can be manifested as schizophrenia agitation, psychotic agitation in patients with psychotic disorders, anxious agitation in patients with severe anxiety, agitated depression or psychomotor agitation in depressive episodes and mixed episodes of bipolar disorder, and Alzheimer's agitation. In clinical practice, agitation is manifested as a series of thinking activities, emotions and behaviors with varying degrees of excitement from low to high, and it is impossible to calm down. Patients often show obvious restlessness and excessive limb activities, accompanied by anxiety. In severe cases, it can manifest as excitement, impulse, threat, aggression, self-harm and other behaviors. The neurobiological mechanism of agitation is still unclear. A summary of relevant studies suggests that abnormal enhancement of dopamine and noradrenergic nerve activity and low γ-aminobutyric acid nerve activity in the brain of individuals may be the potential mechanism of agitation, and abnormal 5-HT (serotonin) nerve activity may also be related to the occurrence of agitation. These neurotransmitter systems regulate and influence each other, and play an important role in the occurrence and development of agitation. Currently, there are no effective drugs approved by the FDA for the treatment of schizophrenia agitation, anxiety agitation, depression agitation, and Alzheimer's agitation symptoms, and clinicians have always been able to rely on the off-target effects of anti-schizophrenia drugs, anti-anxiety drugs, and antidepressant drugs that are already on the market to try to control agitation symptoms. The effectiveness of these drugs in treating agitation is limited. Therefore, there is an urgent need to develop a class of safe and effective drugs for the treatment or control of agitation to improve the overall prognosis of patients. Summary of the invention

[0006] Based on this, one or more embodiments of the present application provide a lithium valproate and its crystal form, preparation method, pharmaceutical composition and application. The lithium valproate of the present application has a more comprehensive therapeutic effect on neurological diseases, good efficacy and good stability, and the crystal form of the lithium valproate of the present application has the advantages of not being easy to absorb moisture and having good stability.

[0007] The technical solution of this application includes the following contents:

[0008] A lithium valproate, the structure of which is as follows:

[0009]

[0010] Furthermore, the lithium valproate is a lithium salt of valproic acid, wherein the chemical ratio of valproic acid to lithium is 1:1.

[0011] Furthermore, the lithium salt of valproic acid is a crystalline salt.

[0012] A method for preparing lithium valproate comprises the following steps:

[0013] After mixing valproic acid, lithium hydroxide and an aqueous solution of alcohol at 0° C. to 10° C., a first solution is obtained;

[0014] Stirring the first solution at 20° C. to 40° C. for 12 h to 20 h to obtain a second solution;

[0015] Filtering the second solution to collect solids to obtain the lithium valproate;

[0016] The structure of the lithium valproate is as follows:

[0017]

[0018] A crystalline form of lithium valproate as described above, selected from any one of the following groups:

[0019] (1) Form I: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.710±0.2°, 7.853±0.2°, 21.674±0.2°, 19.067±0.2°, 20.070±0.2°, 23.617±0.2°, 20.445±0.2° and 15.699±0.2°;

[0020] (2) Form II: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.660±0.2°, 7.503±0.2°, 18.813±0.2°, 19.522±0.2°, 20.058±0.2°, 22.453±0.2°, 22.729±0.2° and 15.093±0.2°;

[0021] (3) Form III: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.703±0.2°, 7.869±0.2°, 21.636±0.2°, 23.632±0.2°, 19.080±0.2°, 20.054±0.2°, 15.713±0.2° and 27.420±0.2°;

[0022] (4) Form IV: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.753±0.2°, 7.883±0.2°, 19.169±0.2°, 21.880±0.2°, 20.263±0.2°, 23.716±0.2°, 15.755±0.2° and 10.930±0.2°;

[0023] (5) Form V: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.741±0.2°, 7.914±0.2°, 21.680±0.2°, 23.673±0.2°, 19.134±0.2°, 20.094±0.2°, 15.756±0.2° and 10.847±0.2°;

[0024] (6) Form VI: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.784±0.2°, 7.946±0.2°, 21.743±0.2°, 19.152±0.2°, 23.707±0.2°, 20.502±0.2°, 20.150±0.2° and 21.164±0.2°; and,

[0025] (7) Form VII: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.729±0.2°, 7.702±0.2°, 18.991±0.2°, 20.702±0.2°, 21.741±0.2°, 22.051±0.2°, 22.533±0.2° and 28.957±0.2°.

[0026] Furthermore, the crystal form of lithium valproate has at least one of the following characteristics:

[0027] (1) The differential scanning calorimetry curve of the crystalline form I has an endothermic peak at 359.2±3°C;

[0028] (2) The differential scanning calorimetry curve of the Form II has an endothermic peak at 361.8±3°C;

[0029] (3) The differential scanning calorimetry curve of the Form III has an endothermic peak at 331.8±3°C;

[0030] (4) The differential scanning calorimetry curve of the Form V has an endothermic peak at 357.2±3°C;

[0031] (6) The differential scanning calorimetry curve of the crystalline form VI has an endothermic peak at 362.3±3° C.; and

[0032] (7) The differential scanning calorimetry curve of the crystalline form VII has an endothermic peak at 362.2±3°C.

[0033] A method for preparing the above-mentioned crystal form of lithium valproate comprises the following steps:

[0034] Take lithium valproate and crystallize it by at least one of dissolution crystallization, anti-solvent crystallization, evaporation crystallization, volatilization crystallization and melt crystallization; wherein the solvent used includes at least one of ethanol, dichloromethane, acetonitrile, ethyl acetate, tetrahydrofuran, methanol, petroleum ether, butyl acetate, methyl tert-butyl ether, n-butanol, dimethyl sulfoxide, tert-butanol, isopropanol, toluene and N,N-dimethylformamide.

[0035] A pharmaceutical composition, characterized in that the pharmaceutical composition comprises a pharmaceutically active ingredient and at least one of a pharmaceutically acceptable excipient and a carrier;

[0036] The active pharmaceutical ingredient includes lithium valproate;

[0037] The structure of the lithium valproate is as follows:

[0038]

[0039] A use of the lithium valproate or the pharmaceutical composition described above in the preparation of a drug for treating and / or preventing nervous system diseases.

[0040] Furthermore, the neurological disease includes at least one of epilepsy, mania, schizophrenia, bipolar disorder, anxiety, depression and agitation.

[0041] The advantages of this application over the prior art include at least the following aspects:

[0042] (1) Sodium valproate and lithium carbonate are commonly used anti-epileptic drugs in clinical practice. The maintenance dose during treatment is 1000mg to 2000mg / day. Excessive dosage often shows related adverse reactions, and the blood lithium concentration needs to be tested during the clinical use of lithium carbonate, while the clinical use of sodium valproate is accompanied by high sodium intake. Magnesium valproate can be used to avoid the high sodium intake of sodium valproate. However, the effect of magnesium valproate after administration is relatively slow and the duration of action is longer. The present application designs and successfully synthesizes lithium valproate. On the one hand, it avoids high salt intake. On the other hand, lithium valproate is more effective than lithium carbonate or sodium valproate alone at the same dose, and compared with sodium valproate and magnesium valproate, it has the effect of treating and / or preventing neurological diseases at low doses.

[0043] (2) The crystal form of sodium valproate disclosed so far exhibits high hygroscopicity, which may cause the drug to absorb water during storage, thereby causing the chemical or physical stability of the drug to decrease and affecting the shelf life of the drug. The present application develops a crystal form of lithium valproate with low hygroscopicity, which ensures a lower water content of the product and makes the quality of lithium valproate more stable during storage.

[0044] (3) The current mainstream antidepressant drugs include selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs). These drugs generally take effect within 2 to 4 weeks. Due to their slow effect, adverse reactions occur before the efficacy of depression patients, especially those with severe depression, appears. The lithium valproate of the present application can take effect quickly and can achieve therapeutic effects within 8 to 10 days, effectively improving patient compliance and efficacy.

[0045] (4) The lithium valproate of the present application has an improving effect on the manifestations of various neurological diseases, including epilepsy, mania, schizophrenia, bipolar disorder, anxiety, depression and agitation. Among them, agitation is a common acute syndrome in psychiatry and a comorbid feature of various neurological diseases including schizophrenia, anxiety, depression, dementia and Alzheimer's disease. At present, there are no effective drugs for treating symptoms including schizophrenia agitation, anxiety agitation, depression agitation and Alzheimer's disease agitation. Clinically, the off-target effects of existing anti-schizophrenia drugs, anti-anxiety drugs and antidepressant drugs are usually used to try to control agitation symptoms, but the efficacy is very limited. The lithium valproate of the present application has a significant anti-agitation effect and can be used to prepare drugs for treating and / or preventing agitation. The anti-agitation mechanism of the lithium valproate of the present application includes delaying the onset of the hyperactivity state caused by MK-801 and reducing the degree of hyperactivity caused by MK-801. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 This is the XPRD spectrum of Form I of lithium valproate prepared in Example 2 of the present application;

[0048] Figure 2 This is the XPRD spectrum of Form II of lithium valproate prepared in Example 2 of the present application;

[0049] Figure 3 This is the XPRD spectrum of Form III of lithium valproate prepared in Example 2 of the present application;

[0050] Figure 4 This is the XPRD spectrum of Form IV of lithium valproate prepared in Example 2 of the present application;

[0051] Figure 5This is the XPRD spectrum of Form V of lithium valproate prepared in Example 2 of the present application;

[0052] Figure 6 This is the XPRD spectrum of Form VI of lithium valproate prepared in Example 2 of the present application;

[0053] Figure 7 This is the XPRD spectrum of Form VII of lithium valproate prepared in Example 2 of the present application;

[0054] Figure 8 This is a graph showing changes in body weight of mice during the modeling of the mouse depression model of Example 5 of the present application (***p<0.001, compared with the normal group);

[0055] Fig. 9 This is a statistical graph of the immobility time in the tail suspension experiment of the mouse depression model in Example 5 of the present application (***p<0.001, compared with the normal group);

[0056] Fig.10 This is a statistical graph of the open field test data of the mouse depression model in Example 5 of the present application (***p<0.05, compared with the normal group);

[0057] Fig.11 This is a statistical graph of the sugar preference rate of the mouse depression model in Example 5 of the present application affected by the test drug (**p<0.01, compared with the normal group);

[0058] Fig.12 This is a statistical graph of the immobility time of the tail suspension test in the mouse depression model of Example 5 of the present application under the influence of the test drug;

[0059] Fig.13 The statistical results of the forced swimming behavior of the mouse depression model in Example 5 of the present application under the influence of the test drug;

[0060] Fig.14 The statistical results of the open field behavior of the mouse depression model in Example 5 of the present application affected by the test drug (***p<0.001, compared with the normal group);

[0061] Fig.15 The statistical results of the effect of lithium valproate on the movement distance of model animals in Example 6 of the present application are as follows: Fig.15 A in the middle is the distance that each group of mice moved every 10 minutes after the injection of MK-801 during the experiment. A total of 120 minutes were recorded, i.e., the movement distance of the mice in 12 10-minute periods. Fig.15 B is the total movement distance of mice in each group within 120 minutes. DETAILED DESCRIPTION

[0062] The present application will be further described below in conjunction with the embodiments and examples. It should be understood that these examples are only used to illustrate the present application and are not intended to limit the scope of the present application. In addition, it should be understood that after reading the content taught in the present application, those skilled in the art may make various changes or modifications to the present application, and these equivalent forms also fall within the protection scope of the claims attached to the present application.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0064] The term "and / or" used in this article includes any one of two or more related listed items, and also includes any and all combinations of related listed items, and the arbitrary and all combinations include any two related listed items, any more related listed items, or all related listed items. It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or", "or / and", and "and / or", it should be understood that in this application, the technical solution undoubtedly includes technical solutions that are all connected by "logical and", and undoubtedly includes technical solutions that are all connected by "logical or". For example, "A and / or B" includes three parallel solutions of A, B and A+B.

[0065] Herein, "preferred", "preferable", "better", etc. are only used to describe implementation methods or examples with better effects. It should be understood that they do not constitute limitations on the scope of protection of this application.

[0066] In the present application, "further" is used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0067] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0068] In the present application, when it comes to numerical intervals (i.e., numerical ranges), unless otherwise specified, the optional numerical distribution is considered continuous within the above numerical interval, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical range, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to integers within the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges included therein.

[0069] The temperature parameters in this application, unless otherwise specified, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±0.5°C, ±0.4°C, ±0.3°C, ±0.2°C, and ±0.1°C are allowed.

[0070] The room temperature in this application generally refers to 20°C to 40°C.

[0071] In the present application, weight may be μg, mg, g, kg or other mass units known in the chemical industry.

[0072] Compounds of the present application

[0073] In this application, the compound refers to lithium valproate.

[0074] The structural formula of lithium valproate is:

[0075] The crystal forms of valproate are Form I, Form II, Form III, Form IV, Form V, Form VI and Form VII.

[0076] crystallization

[0077] The solubility limit of the compound can be exceeded by operating the solution, thereby completing the crystallization of production scale. This can be accomplished by a variety of methods, for example, dissolving the compound at a relatively high temperature, then cooling the solution to below the saturation limit or by boiling, atmospheric evaporation, vacuum drying or by some other methods to reduce the liquid volume. The solubility of the compound can be reduced by adding an anti-solvent or a solvent or a mixture of such solvents in which the compound has a low solubility. Another alternative method is to adjust the pH value to reduce the solubility. For a detailed description of the crystallization, see Crystallization, the third edition, JW Mullens, Butterworth Heineman Ltd.1993, ISBN0750611294.

[0078] Identification and properties of crystal forms

[0079] After preparing compounds with different crystal forms, the present application used the following methods and instruments to study their properties.

[0080] X-ray powder diffraction (XRPD)

[0081] Methods for determining X-ray powder diffraction of crystal forms are known in the art. XRPD can detect information such as changes in crystal forms, crystallinity, and crystal structure states, and is a common means of identifying crystal forms. The peak position of the XRPD spectrum depends mainly on the structure of the crystal form. The measurement of 2θ in the XRPD spectrum may be slightly different between different instruments, so the value of 2θ cannot be considered absolute. According to the instrument conditions used in the experiment of this application, there is an error of ±0.2° in the diffraction peak. It can be understood that the range of error is not absolute for different test instruments and test conditions. The crystal form of the compound of the present application has a specific crystal morphology and has a specific characteristic peak in the XRPD diagram.

[0082] In the present application, “the X-ray powder diffraction pattern has a characteristic diffraction peak at a specific 2θ angle” means that the peak value of the peak is within the indicated numerical range, at the indicated numerical point, near the indicated numerical range, or near the indicated numerical point.

[0083] Due to different measuring factors such as measuring instruments and measuring conditions, the position of a peak or some peaks in the actual X-ray powder diffraction pattern may be slightly offset, that is, there may be a slight difference between the characteristic peak combination or X-ray powder diffraction pattern indicated in this application, but it is understandable that for those skilled in the art, it is possible to identify as a whole whether a slightly different characteristic peak combination or X-ray powder diffraction pattern can substantially constitute the crystal form described in this application. Therefore, those that are substantially identified as being consistent with the crystal form of this application should be considered to be within the scope of protection of this application.

[0084] For example, "the X-ray powder diffraction pattern has a peak at a diffraction angle of 6.710±0.2°" means that the peak value of the peak can be located within the range of 6.710±0.2° or near the range, as long as it does not affect the overall identification of the crystal form. In addition, the "±0.2" here only indicates the error of the peak value in the diffraction angle position, and has nothing to do with the peak shape and peak width of the peak.

[0085] In the present application, the word "substantially" in "the X-ray powder diffraction pattern is substantially as represented by a specific pattern" should be understood similarly. As long as it can be determined as a whole that a certain X-ray powder diffraction pattern is substantially consistent with the X-ray powder diffraction pattern described in the present application, it should be deemed to fall within the scope of protection of the present application.

[0086] It is understandable that the differential scanning calorimetry curves in the present application and the positions of the endothermic peaks shown therein should also be understood in a similar manner, and slight discrepancies with the specific values ​​or specific numerical ranges or specific spectra disclosed in the present application are allowed. However, as long as it can be determined as a whole that some or all of the endothermic peak positions in the differential scanning calorimetry curve, or the entire curve, are substantially consistent with the present application, they should be considered to fall within the protection scope of the present application.

[0087] It is to be understood that similar understanding can be applied to other spectra characterizing crystal types.

[0088] Differential Scanning Calorimetry (DSC)

[0089] Also known as "differential scanning calorimetry", it is a technique that measures the relationship between the energy difference and temperature between the substance being tested and the reference substance during the heating process. The peak position, shape and number of peaks on the DSC spectrum are related to the properties of the substance, so they can be used to qualitatively identify the substance. This method is commonly used in this field to detect various parameters such as the phase transition temperature, glass transition temperature, reaction heat, etc. of a substance. The peak position of the DSC spectrum may vary slightly between different instruments, so the value of the peak position of the DSC endothermic peak cannot be considered absolute. Depending on the condition of the instrument used in the experiment of this application, the numerical value of the experimental error or difference may be less than or equal to 5°C, or less than or equal to 4°C, or less than or equal to 3°C, or less than or equal to 2°C, or less than or equal to 1°C.

[0090] Identification and properties of crystal forms

[0091] X-ray powder diffraction

[0092] The compound of the present application has a specific crystal form and has specific characteristic peaks in the X-ray powder diffraction pattern (XPRD).

[0093] The XPRD spectra were collected on an X-ray powder diffraction analyzer, and the instrument parameters are shown in Table 1.

[0094] Table 1

[0095]

[0096] In the X-ray powder diffraction pattern, the position of each peak is determined by 2θ (°). It is understood that different instruments and / or conditions may result in slightly different data, and the position and relative intensity of each peak may vary. The intensity division of the peak only reflects the approximate size of the peak at each position. In this application, each crystal form is used as the base peak with the highest peak height, and its relative intensity is defined as 100%, as I0, and the ratio of its peak height to the base peak height of each other peak is used as its relative intensity I / I0, and the division definition of the relative intensity of each peak is as shown in Table 2.

[0097] Table 2

[0098] <![CDATA[Relative Strength II0 (%)]]> definition 50～100 VS (very strong) 25～50 S (Strong) 10～25 M (Medium) 1～10 W(weak) .

[0099] Sodium valproate and lithium carbonate are commonly used anti-epileptic drugs in clinical practice. The maintenance dose during treatment is 1000mg to 2000mg / day. Excessive doses often show related adverse reactions, and blood lithium concentrations need to be tested when lithium carbonate is used clinically, while sodium valproate is accompanied by high sodium intake when used clinically. Magnesium valproate can be used to avoid high sodium intake of sodium valproate, however, the effect of magnesium valproate is slow after administration and the duration of action is longer.

[0100] To solve the above problems, the present application designed and successfully synthesized lithium valproate, which avoids high salt intake and is more effective than single lithium carbonate or sodium valproate at the same dose, and has the effect of treating and / or preventing neurological diseases at low doses compared to sodium valproate and magnesium valproate.

[0101] The lithium valproate in the embodiment of the present application has the following structure:

[0102]

[0103] In some embodiments, the lithium valproate is the lithium salt of valproic acid.

[0104] In some embodiments, the chemical ratio of valproic acid and lithium is 1:1.

[0105] In some embodiments, the lithium salt of valproic acid is a crystalline salt.

[0106] One or more embodiments of the present application provide a method for preparing lithium valproate, comprising the following steps:

[0107] After mixing valproic acid, lithium hydroxide and an aqueous solution of alcohol at 0° C. to 10° C., a first solution is obtained;

[0108] Stirring the first solution at 20° C. to 40° C. for 12 h to 20 h to obtain a second solution;

[0109] The second solution is filtered to collect solids to obtain lithium valproate;

[0110] The structure of lithium valproate is as follows:

[0111]

[0112] In some embodiments, the alcohol aqueous solution contains alcohol and water in a volume ratio of 15 to 25:1, for example 15:1, 20:1, 25:1, etc.

[0113] In some embodiments, the alcohol is selected from organic alcohols such as ethanol, methanol, etc.

[0114] In some embodiments, the mass volume ratio of the aqueous solution of valproic acid and alcohol is 8-12 g:100 mL, for example 8 g:100 mL, 9 g:100 mL, 10 g:100 mL, 11 g:100 mL, 12 g:100 mL, etc., to ensure that valproic acid is fully dissolved.

[0115] In some embodiments, the molar ratio of valproic acid and lithium hydroxide is 2:(1-1.5), for example 2:1, 2:1.2, 2:1.5, etc. A slight excess of lithium valproate can ensure sufficient reaction, and the subsequent valproic acid is easily removed from the system.

[0116] In some embodiments, valproic acid, lithium hydroxide and alcohol are mixed at 0°C to 10°C to obtain a first solution, comprising:

[0117] After mixing the aqueous solution of valproic acid and alcohol, solid lithium hydroxide is added at 0°C to 10°C. After the addition is complete, the mixture is stirred for a period of time to fully dissolve, thereby obtaining a first solution.

[0118] In some embodiments, the first solution is stirred at 20° C. to 40° C. for 12 h to 20 h to obtain a second solution. The first solution is fully stirred at a suitable temperature to fully react to generate lithium valproate.

[0119] In some embodiments, filtering the second solution and collecting the solid to obtain lithium valproate comprises:

[0120] Filter the second solution at room temperature, which is usually 20°C to 40°C;

[0121] After filtration, concentrate at 40-60°C and 10-20 bar;

[0122] After concentration, vacuum drying is carried out at 40-60° C. and below 0.09 MPa, and solids are collected to obtain lithium valproate.

[0123] The crystal form of sodium valproate disclosed so far exhibits high hygroscopicity, while the crystal form of lithium valproate of the present application has low hygroscopicity, which ensures a lower water content of the product and makes the quality of lithium valproate more stable during storage.

[0124] One or more embodiments of the present application provide a crystalline form of lithium valproate selected from any one of the following groups:

[0125] (1) Form I: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.710±0.2°, 7.853±0.2°, 21.674±0.2°, 19.067±0.2°, 20.070±0.2°, 23.617±0.2°, 20.445±0.2° and 15.699±0.2°;

[0126] (2) Form II: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.660±0.2°, 7.503±0.2°, 18.813±0.2°, 19.522±0.2°, 20.058±0.2°, 22.453±0.2°, 22.729±0.2° and 15.093±0.2°;

[0127] (3) Form III: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.703±0.2°, 7.869±0.2°, 21.636±0.2°, 23.632±0.2°, 19.080±0.2°, 20.054±0.2°, 15.713±0.2° and 27.420±0.2°;

[0128] (4) Form IV: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.753±0.2°, 7.883±0.2°, 19.169±0.2°, 21.880±0.2°, 20.263±0.2°, 23.716±0.2°, 15.755±0.2° and 10.930±0.2°;

[0129] (5) Form V: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.741±0.2°, 7.914±0.2°, 21.680±0.2°, 23.673±0.2°, 19.134±0.2°, 20.094±0.2°, 15.756±0.2° and 10.847±0.2°;

[0130] (6) Form VI: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.784±0.2°, 7.946±0.2°, 21.743±0.2°, 19.152±0.2°, 23.707±0.2°, 20.502±0.2°, 20.150±0.2° and 21.164±0.2°; and,

[0131] (7) Form VII: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.729±0.2°, 7.702±0.2°, 18.991±0.2°, 20.702±0.2°, 21.741±0.2°, 22.051±0.2°, 22.533±0.2° and 28.957±0.2°.

[0132] In some embodiments, the crystalline form of lithium valproate has at least one of the following characteristics:

[0133] (1) The X-ray powder diffraction pattern of Form I is basically as follows Figure 1 As shown;

[0134] (2) The X-ray powder diffraction pattern of Form II is basically as follows Figure 2 As shown;

[0135] (3) The X-ray powder diffraction pattern of Form III is basically as follows Figure 3 As shown;

[0136] (4) The X-ray powder diffraction pattern of Form IV is basically as follows Figure 4 As shown;

[0137] (5) The X-ray powder diffraction pattern of Form V is basically as follows Figure 5 As shown;

[0138] (6) The X-ray powder diffraction pattern of Form VI is basically as follows Figure 6 shown; and,

[0139] (7) The X-ray powder diffraction pattern of Form VII is basically as follows Figure 7 shown.

[0140] In some embodiments, the crystalline form of lithium valproate has at least one of the following characteristics:

[0141] (1) The differential scanning calorimetry curve of Form I has an endothermic peak at 359.2±3°C;

[0142] (2) The differential scanning calorimetry curve of Form II has an endothermic peak at 361.8±3°C;

[0143] (3) The differential scanning calorimetry curve of Form III has an endothermic peak at 331.8±3°C;

[0144] (4) The differential scanning calorimetry curve of Form V has an endothermic peak at 357.2±3°C;

[0145] (6) the differential scanning calorimetry curve of Form VI has an endothermic peak at 362.3±3°C; and

[0146] (7) The differential scanning calorimetry curve of Form VII has an endothermic peak at 362.2±3°C.

[0147] One or more embodiments of the present application provide a method for preparing the above-mentioned crystal form of lithium valproate, comprising the following steps:

[0148] Take lithium valproate and crystallize it by at least one of dissolution crystallization, anti-solvent crystallization, evaporation crystallization, volatilization crystallization and melt crystallization; wherein the solvent used includes at least one of ethanol, dichloromethane, acetonitrile, ethyl acetate, tetrahydrofuran, methanol, petroleum ether, butyl acetate, methyl tert-butyl ether, n-butanol, dimethyl sulfoxide, tert-butyl alcohol, isopropanol, toluene and N,N-dimethylformamide. Among them, ethyl acetate, dichloromethane and acetonitrile are poorly soluble solvents, isopropanol, tert-butyl alcohol, butyl acetate, methyl tert-butyl ether, tetrahydrofuran and toluene are slightly soluble solvents, n-butanol is a soluble solvent, and methanol, ethanol and water are readily soluble solvents.

[0149] In this article, a sparingly soluble solvent refers to a compound in which the compound is not dissolved by ultrasound or heating, and is a white turbid liquid; a slightly soluble solvent refers to a compound in which the compound is not dissolved by heating or ultrasound, but is dispersed as a white dispersion system; a soluble solvent refers to a compound in which the compound is dissolved by ultrasound, and is a colorless clear liquid; and a readily soluble solvent refers to a compound in which the compound is mixed and dissolved, and is a colorless clear liquid.

[0150] In this article, dissolution crystallization is a process in which a compound is prepared into a saturated solution with a readily soluble solvent, and then added dropwise to another heated readily soluble solvent to mix, and then crystals are precipitated; antisolvent crystallization is a process in which a compound is mixed with at least one of a sparingly soluble solvent, a soluble solvent and a slightly soluble solvent, and then dissolved by heating, and then cooled to precipitate crystals; evaporation crystallization is a process in which a compound, a readily soluble solvent and at least one of a sparingly soluble solvent, a soluble solvent and a slightly soluble solvent are mixed and dissolved, and then crystals are precipitated after concentration treatment; volatilization crystallization is a process in which a compound is dissolved in a readily soluble solvent and then evaporated to precipitate crystals; melt crystallization is a process in which a compound is heated to melt and then cooled to crystallize; the heating and melting temperature in this application is 300°C, and the heating time is 2 to 24 hours.

[0151] One or more embodiments of the present application provide a pharmaceutical composition, which includes a pharmaceutically active ingredient and at least one of a pharmaceutically acceptable excipient and a carrier;

[0152] The active ingredients of the drug include lithium valproate;

[0153] The structure of lithium valproate is as follows:

[0154]

[0155] As used herein, "pharmaceutically acceptable carriers" should be non-toxic and inert in principle. "The form of pharmaceutically acceptable carriers is not particularly limited, including but not limited to solid, semi-solid, liquid, etc. The pharmaceutically acceptable carrier should be compatible with the patient. The patient is preferably a mammal, more preferably a human. One of the functions of the pharmaceutically acceptable carrier is to be suitable for delivering the active agent to the target without terminating the activity of the agent. As used herein, the language "pharmaceutically acceptable carrier" includes buffers, sterile water for injection, solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and the like that are compatible with drug administration. Each carrier must be "pharmaceutically acceptable" in the sense of being compatible with other ingredients in the formulation and not harmful to the patient.

[0156] As used herein, "pharmaceutically acceptable excipients" include, but are not limited to, diluents, wetting agents, binders, disintegrants, lubricants, color and flavor regulators, solvents, solubilizers, cosolvents, emulsifiers, antioxidants, metal complexing agents, inert gases, preservatives, local analgesics, pH regulators, isotonic or isotonic regulators, etc. Further: diluents, such as starch, sucrose, cellulose, inorganic salts, etc.; wetting agents, such as water, ethanol, etc.; binders, such as starch slurry, dextrin, sugar, cellulose derivatives, gelatin, polyvidone, polyethylene glycol, etc.; disintegrants, such as starch, sodium carboxymethyl starch, low-substituted hydroxypropyl cellulose, sodium cross-linked polyvidone, surfactants, runteng disintegrants, etc.; lubricants, such as talc, calcium stearate, magnesium stearate, magnesium lauryl sulfate, micro-powder silica gel, polyethylene glycol, etc.; color and flavor regulators, such as pigments, flavors, sweeteners, Flavoring agents, adhesives, deodorants, etc., such as fuchsin and xylitol; solvents, such as water, oil, ethanol, glycerol, propylene glycol, polyethylene glycol, dimethyl sulfoxide, liquid paraffin, fatty oil, ethyl acetate, etc.; solubilizers, such as Tweens, sorbents, polyoxyethylene fatty alcohol ethers, soaps, sulfates, sulfonates, etc.; cosolvents, such as organic acids (such as citric acid) and their salts, amide and amine compounds, inorganic salts, polyethylene glycol, povidone, glycerol, etc.; emulsifiers, such as spans, tweens, sorbents, benzyls, glycerol fatty acid esters, high fatty acid salts, sulfates, sulfonates, gum arabic, tragacanth gum, gelatin, pectin, phospholipids, agar, sodium alginate, hydroxides, silicon dioxide, bentonite, etc.; suspending agents, such as glycerol, syrup, gum arabic, tragacanth gum, agar, sodium alginate, cellulose derivatives, povidone, carbopol, polyvinyl alcohol, thixotropic glue, etc.; antioxidants, such as sulfites, pyrosulfites, bisulfites, ascorbic acid, gallic acid and its esters, etc.; metal complexing agents, such as disodium ethylenediaminetetraacetic acid, polycarboxylic acid compounds, etc.; inert gases, such as Nitrogen, carbon dioxide, etc.; preservatives, such as parabens, organic acids and their salts (such as sodium benzoate), quaternary ammonium compounds, chlorhexidine acetate, alcohols, phenols and volatile oils, etc.; local analgesics, such as benzyl alcohol, chlorobutanol, lidocaine and procaine, etc.; pH adjusters, such as hydrochloric acid, sulfuric acid, phosphoric acid, tartaric acid, acetic acid, sodium hydroxide, sodium bicarbonate, ethylenediamine, meglumine, phosphates, acetates, citric acid, citrate, etc.; isotonic or isotonic adjusters, such as glucose, sodium chloride, sodium citrate, sorbitol and xylitol, etc.It can be understood that the diluent described in the embodiments of the present application can also be called a filler, which plays the same role in the pharmaceutical preparation; the water described in the embodiments of the present application is water that meets the requirements of the medicine, such as water for injection, purified water, etc., and the oil is oil for injection; the preservative described in the embodiments of the present application can also be called an antibacterial agent, which plays a role in inhibiting the growth of microorganisms and prolonging the shelf life in the preparation; the lubricant described in the embodiments of the present application contains a flow aid, an anti-adhesive agent, etc.; the sugar described in the embodiments of the present application can be powdered sugar or syrup, and the type of sugar is not limited to glucose; the flavors described in the embodiments of the present application include but are not limited to flavors.

[0157] In some embodiments, the pharmaceutical composition includes a therapeutically effective amount of a pharmaceutically active ingredient.

[0158] As used herein, "therapeutically effective amount" refers to the amount of the compound of the present invention that will elicit a biological or medical response in a subject, such as reducing or inhibiting enzyme or protein activity or improving symptoms, alleviating symptoms, slowing or delaying disease progression, or preventing disease.

[0159] One or more embodiments of the present application provide a use of the above-mentioned lithium valproate or pharmaceutical composition in the preparation of a drug for treating and / or preventing nervous system diseases.

[0160] As used herein, "prevent and / or treat" refers to reducing, slowing the progression, attenuating, preventing, or maintaining an existing disease or condition, such as a neurological disease. Treatment also includes curing, preventing the development of, or alleviating to some extent, one or more symptoms of a disease or condition.

[0161] In some embodiments, the neurological disorder comprises at least one of epilepsy, mania, schizophrenia, bipolar disorder, anxiety, depression, and agitation.

[0162] Furthermore, the agitation includes at least one of schizophrenia agitation, anxiety agitation, depression agitation and Alzheimer's agitation.

[0163] In some embodiments, the subject of the drug for treating and / or preventing a nervous system disease is a mammal.

[0164] As used herein, "subject" refers to an animal, preferably a mammal, more preferably a human. The term "mammal" refers to warm-blooded vertebrate mammals, including cats, dogs, rabbits, bears, foxes, wolves, monkeys, deer, mice, pigs and humans.

[0165] In some embodiments, the mammal includes at least one of a human and a mouse.

[0166] In some embodiments, the dosage form of the drug for treating and / or preventing a nervous system disease includes a solid preparation, a semisolid preparation, or a liquid preparation.

[0167] In some embodiments, the dosage forms of the drug for treating and / or preventing nervous system diseases include tablets, capsules, granules, powders, granules, pills, pills, ointments, creams, suspensions and solutions.

[0168] The administration method of the compound of the present application is not particularly limited.

[0169] Representative routes of administration include, but are not limited to, oral, rectal, parenteral (intravenous, intramuscular or subcutaneous) injection, and topical administration, inhalation.

[0170] Solid dosage forms for oral administration include capsules, tablets, pills, powders and granules. In these solid dosage forms, the active compound is mixed with at least one conventional inert excipient (or carrier), such as sodium citrate or dicalcium phosphate, or with the following ingredients: (a) fillers or extenders, for example, starches, lactose, sucrose, glucose, mannitol, and silicic acid; (b) binders, for example, hydroxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, sucrose, and acacia; (c) humectants, for example, glycerol; (d) disintegrants, for example, agar, calcium carbonate, potato starch or tapioca starch, alginic acid, certain complex silicates, and sodium carbonate; (e) solubilizers, for example, paraffin; (f) absorption accelerators, for example, quaternary ammonium compounds; (g) wetting agents, for example, cetyl alcohol and glyceryl monostearate; (h) adsorbents, for example, kaolin; and (i) lubricants, for example, talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, or mixtures thereof. In capsules, tablets and pills, the dosage form may also contain a buffer. Solid dosage forms such as tablets, sugar pills, capsules, pills and granules may be prepared using coatings and shell materials, such as enteric coatings and other materials known in the art. They may contain opacifiers, and the release of the active compound or compounds in such compositions may be delayed in a certain part of the digestive tract. Examples of embedding components that may be used are polymeric substances and waxes. If necessary, the active compound may also be formed into microcapsules with one or more of the above-mentioned excipients.

[0171] Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups or tinctures. In addition to the active compound, the liquid dosage form may include inert diluents conventionally used in the art, such as water or other solvents, solubilizers and emulsifiers, specifically for example, ethanol, isopropanol, ethyl carbonate, ethyl acetate, propylene glycol, 1,3-butylene glycol, dimethylformamide and oils, particularly cottonseed oil, peanut oil, corn germ oil, olive oil, castor oil and sesame oil or a mixture of these substances. In addition to these inert diluents, the composition may also include adjuvants, such as wetting agents, emulsifiers and suspending agents, sweeteners, flavoring agents and spices. For example, a suspension may include a suspending agent, specifically for example, ethoxylated isostearyl alcohol, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum methylate and agar or a mixture of these substances.

[0172] Compositions for parenteral injection may include physiologically acceptable sterile aqueous or anhydrous solutions, dispersions, suspensions or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Suitable aqueous or non-aqueous carriers, diluents, solvents or excipients include water, ethanol, polyols and suitable mixtures thereof.

[0173] Dosage forms for topical administration include ointments, powders, patches, sprays and inhalants, which are prepared by mixing the active ingredient with a pharmaceutically acceptable carrier and any preservatives, buffers, or propellants that may be required under sterile conditions.

[0174] It is understandable that the drugs of the embodiments of the present application can be added with different pharmaceutically acceptable excipients to prepare suitable clinical dosage forms, which include but are not limited to the dosage forms described above.

[0175] In some embodiments, the administration frequency is 1 to 3 times / day, for example, once / day, twice / day, or three times / day.

[0176] In some embodiments, the dosage is 250-1000 mg / day.

[0177] In some embodiments, the subject is a mouse and the dosage is 30 to 200 mg / kg.

[0178] In some embodiments, the subject is a human and the dosage is 4 to 20 mg / kg.

[0179] In some embodiments, the administration is oral.

[0180] In some embodiments, the administration method is intragastric administration. Intragastric administration in the present application means: dissolving the drug in a solvent (such as ultrapure water), and using an intragastric instillation device to directly inject the drug solution into the stomach of the animal through the animal's mouth.

[0181] At present, the main clinical antidepressants are selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), etc. These drugs generally take effect within 2 to 4 weeks. Due to the slow effect, for depressed patients, especially severe patients, adverse reactions appear before the efficacy appears. Patients often refuse to take medication within 1 to 2 weeks, and even commit suicide during this period, which becomes a clinical pain point of antidepressants. The lithium valproate of the present application has a rapid onset of action, and can achieve therapeutic effects in 8 to 10 days, effectively improving patient compliance and improving efficacy.

[0182] The lithium valproate of the present application has an improving effect on the manifestations of various neurological diseases, including epilepsy, mania, schizophrenia, bipolar disorder, anxiety, depression and agitation, wherein agitation includes schizophrenia agitation, anxiety agitation, depression agitation and Alzheimer's agitation, and the anti-agitation mechanism includes delaying the onset of the hyperactivity state caused by MK-801 and reducing the degree of hyperactivity caused by MK-801.

[0183] The following are some specific embodiments.

[0184] For experimental parameters not specified in the following specific embodiments, reference is made to the instructions given in the present application document, and reference may also be made to experimental manuals in the art or other experimental methods known in the art, or to experimental conditions recommended by manufacturers.

[0185] All or part of the raw materials involved in the following specific examples are shown in Table 1, and the reagents are shown in Table 2. The remaining raw materials and reagents can be obtained from the market, or can be prepared by those skilled in the art according to known means.

[0186] Table 3

[0187] Material Name Valproic acid Lithium hydroxide CAS Number 99-66-1 1310-65-2 source Shanghai Adamas Shanghai Aladdin batch number P2284353 L128667 Molecular formula <![CDATA[C8H 16 O2]]> LiOH Molecular weight 144.21 23.95 Melting point -21.25℃(estimate) 470℃(dec.)(lit.) Boiling Point 220℃(lit.) 925℃(lit.) density 0.9g / mL at 25℃(lit.) <![CDATA[1.43g / cm 3 At 25℃(lit.)]]>

[0188] Table 4

[0189]

[0190] In the following specific embodiments, the crystal form judgment standard refers to the 2020 edition of the "Chinese Pharmacopoeia" 9015 Drug Crystal Form Research and Crystal Form Quality Control Guidelines. If the crystal form material state of two crystalline samples is judged to be consistent, the powder X-ray diffraction test should be carried out in parallel, and the number of diffraction peaks should be the same, the error range of the 2θ value diffraction peak position of the two is within 0.2°, the relative peak intensity error of the diffraction peak at the same position is within ±5%, and the order of the intensity of the diffraction peaks should be consistent; if the crystal form material state of two amorphous samples is judged to be consistent, the geometric topological shape of the diffuse diffraction peak should be completely consistent.

[0191] The experiments and principles performed in the following examples are as follows:

[0192] Tail suspension test (TST) is a classic method that can quickly evaluate the efficacy of antidepressants, stimulants, and sedatives. The principle is to use the fact that mice attempt to escape after being suspended by their tails but cannot escape, so they give up struggling and enter a unique state of depression and immobility. During the experiment, the immobility time of the animals is recorded to reflect the state of depression. Antidepressants and stimulants can significantly shorten and change their state.

[0193] The Open Field Test (OFT) is a method used to evaluate the behavior of experimental animals, especially in neuropsychiatric research, and is often used to measure the spontaneous activity, exploratory behavior, and anxiety and depression-like behaviors of animals. The open field test can measure the spontaneous activity level and exploratory behavior of animals in a new environment. Patients with depression often show reduced activity and lack of interest.

[0194] The sucrose preference test is a classic test for detecting anhedonia, a typical symptom of depression. It is a test method designed by using the rodents' preference for sweet taste. After the animals have fasted for a period of time, they are given plain water and low-concentration sucrose water at the same time. The animals' preference for sucrose water (sucrose preference) is used as an indicator to detect whether the animals have anhedonia, a symptom of depression.

[0195] The mice used in the following examples are C57BL / 6j mice, which are commonly used animals for drug efficacy tests of test products used or intended for human use, and are widely used in pharmacology, drug efficacy and disease model exploration. In terms of gender, considering that changes in sex hormones in female mice will have a greater impact on behavioral and neurochemical indicators, it is recommended to use male C57BL / 6j mice.

[0196] The term (+)-MK-801 is a highly selective, potent inhibitory noncompetitive NMDA receptor antagonist that can simulate typical positive symptoms, negative symptoms and cognitive impairment symptoms of schizophrenia and is considered to be one of the best schizophrenia modeling drugs.

[0197] Example 1 Preparation of lithium valproate

[0198] 1.1 Synthesis route

[0199]

[0200] 1.2 Preparation method

[0201] (1) Prepare a 1 L three-necked flask, add valproic acid (28.8 g, 2 mol) and ethanol / purified water (273.6 mL / 14.4 mL), cool the system to 0°C to 10°C, add solid lithium hydroxide (5.7 g, 2.4 mol, 1.2 equivalents) to the system, mix well, and stir overnight at room temperature of 20°C to 30°C for about 18 hours;

[0202] (2) filtering at room temperature, concentrating the filtrate at 50° C. and 14 bar, and vacuum drying at 50° C. and below 0.09 MPa to obtain lithium valproate powder.

[0203] 1.3 Characterization results

[0204] HRMS data: [M+H] + Calculated value = 151.1305; [M+H] + Actual value = 151.1306;

[0205] Proton spectrum data: 1 H NMR (CD3OD, 400MHz): δ2.19(1H,m),1.59~1.48(2H,m),1.42–1.25(6H,m),0.90(6H,t,J=7.2Hz);

[0206] Carbon spectrum data: 13 C NMR (CD3OD, 101MHz): δ185.3, 50.2, 36.9, 22.0, 14.5.

[0207] Example 2 Preparation of Crystalline Forms of Lithium Valproate

[0208] 2.1 Form I

[0209] (1) Take crude lithium valproate (1.0 g, 6.7 mmol) into a round-bottom flask of appropriate specifications, add tetrahydrofuran (30 mL), and react at reflux temperature overnight.

[0210] (2) Filter while hot, rinse the filter cake with tetrahydrofuran (10 mL), and vacuum dry at 100° C. and less than 0.09 MPa for 18 hours.

[0211] 2.2 Form II

[0212] (1) Take a round-bottom flask of appropriate specifications, add acetonitrile (100 mL), and heat to 60°C and keep warm; add a saturated aqueous solution (10 mL) of lithium valproate (3.6 g, 24 mmol) to the hot acetonitrile dropwise, stir for 20 minutes after the addition is complete, turn off the heating, and stir at room temperature overnight.

[0213] (2) Filter at room temperature, wash the filter cake with a small amount of acetonitrile, and vacuum dry at 50°C and less than 0.09 MPa for 7 hours.

[0214] 2.3 Form III

[0215] (1) Take a round-bottom flask of appropriate specifications, add solvent II (100 mL / 150 mL, 100 V / 150 V), raise the temperature to 60° C., and dropwise add a saturated solution I (2.8 V / 10 V) of crude lithium valproate (3.6 g / 3.0 g / 1.5 g, 24 mmol / 20 mmol / 10 mmol, 1.0 equivalent) into solvent II. After the addition is complete, stir for 20 min, turn off the heating, and stir at room temperature overnight.

[0216] (2) Filter at room temperature, wash the filter cake with a small amount of solvent II, vacuum dry at 50°C / <0.09MPa for 7 hours, and take samples for testing.

[0217] 2.4 Form IV

[0218] (1) Take crude lithium valproate (1.0 g, 6.7 mmol) into a round-bottom flask of appropriate specifications, add ethyl acetate (100 mL) and ethanol (20 mL), dissolve under ultrasonication, filter at room temperature, and concentrate to a total solvent volume of 24 mL-36 mL at an appropriate temperature, and crystallize at room temperature overnight.

[0219] (2) Filter at room temperature, rinse the filter cake with ethyl acetate (5 mL), and vacuum dry at 100° C. and less than 0.09 MPa for 18 hours.

[0220] 2.5 Crystalline Form V

[0221] (1) Preparation of crude lithium valproate solution: Take a 40 mL sample bottle, add 200 mg of crude lithium valproate, and dissolve it with 2 mL of methanol under ultrasonic conditions. Filter through cotton to obtain a clear 100 mg / mL crude lithium valproate methanol solution for use.

[0222] (2) Take a 1.5 mL epoxies and add a total of 15-25 mg of crude lithium valproate solution to each epoxies, and add an equal volume of petroleum ether. The partially precipitated crystals are dissolved under ultrasonic conditions. The epoxies are slightly opened and stored at room temperature in the dark. The solvent volatilization is observed and recorded every day until the solvent is evaporated, and vacuum dried at 100°C / <0.09MPa.

[0223] 2.6 Form VI

[0224] The crude lithium valproate was placed in a muffle furnace, baked at 300° C. for 2 hours, and then cooled.

[0225] 2.7 Form VII

[0226] (1) Take a round-bottom flask of appropriate specifications, add tetrahydrofuran (100 mL), raise the temperature to 60°C, and dropwise add a saturated aqueous solution (10 mL) of crude lithium valproate (3.6 g, 24 mmol) into tetrahydrofuran. After the addition is complete, stir for 20 minutes, turn off the heating, and stir at room temperature overnight.

[0227] (2) Filter at room temperature, wash the filter cake with a small amount of tetrahydrofuran, vacuum dry at 50°C / <0.09MPa for 7 hours, and take a sample for testing.

[0228] 2.8 Crystal form summary

[0229] Table 5 Summary of crystal forms

[0230]

[0231] Example 3 Investigation of the hygroscopicity of different crystalline forms of lithium valproate

[0232] 3.1 Test drugs and equipment

[0233] The test drug information is shown in Table 6, and the equipment information is shown in Table 7.

[0234] Table 6

[0235] Sample name Sample source Lithium valproate crystal form I Form I of Example 2 Lithium valproate crystal form III Form III of Example 2 Lithium valproate crystal form IV Form IV of Example 2 Lithium Valproate Form V Form V of Example 2 Lithium valproate crystal form VI Form VI of Example 2 Sodium valproate Purchase

[0236] In Table 6, after Form VI was melted in a muffle furnace at 300°C for 2 h, the hygroscopicity curve was examined.

[0237] Table 7

[0238]

[0239] 3.2 Inspection Method

[0240] The determination is carried out according to the Guiding Principles of Drug Hygroscopicity Test (Chinese Pharmacopoeia 2020 Edition Part IV General Rules 9103), including the following steps:

[0241] (1) Take a dry stoppered glass weighing bottle and place it in a suitable constant temperature desiccator at 25℃±1℃ (select saturated aqueous solution according to different humidity) or artificial climate box (temperature of 25℃±1℃, set humidity series) for pre-saturation one day before the test, and accurately weigh the weight (m1).

[0242] (2) Take an appropriate amount of the sample and spread it evenly in the weighing bottle. The thickness of the sample should be about 1 mm and weigh it accurately (m2).

[0243] (3) Open the weighing bottle and place it with the bottle cap under the above constant temperature and humidity conditions for 24 hours. Weigh accurately (m3).

[0244] (4) Calculation formula:

[0245] Weight gain percentage = m 3 -m 2 ×100%

[0246] m2-m1

[0247] (5) Description of hygroscopic characteristics and definition of hygroscopic weight gain:

[0248] Deliquesce: Absorbs enough water to form a liquid;

[0249] Highly hygroscopic: weight gain due to moisture absorption is not less than 15%;

[0250] Hygroscopic: weight gain due to moisture absorption is less than 15% but not less than 2%;

[0251] Slightly hygroscopic: weight gain due to moisture absorption is less than 2% but not less than 0.2%;

[0252] No or almost no hygroscopicity: weight gain due to moisture is less than 0.2%.

[0253] 3.3 Survey Results

[0254] Table 8 Hygroscopicity curve investigation results

[0255]

[0256] According to the statistical data in Table 8, it can be found that the hygroscopicity of lithium valproate in each crystal form is weaker than that of sodium valproate and more stable. Crystal forms I, III, IV and V of lithium valproate are hygroscopic, while crystal form VI is not hygroscopic. Crystal form VI is a stable crystal form.

[0257] Example 4 Application of lithium valproate in the preparation of anti-epileptic drugs

[0258] This example provides the use of the lithium valproate of the present application in the preparation of an anti-epileptic drug, which is verified by an exploratory test on an acute pentylenetetrazol epilepsy ignition model. The reagents used in this example are prepared under a sterile environment.

[0259] 4.1 Experimental Materials

[0260] (1) Drug testing

[0261] The lithium valproate prepared in Example 1 was used to conduct an exploratory test on the acute pentylenetetrazol epilepsy kindling model.

[0262] Ultrapure water was used as the solvent for preparation. Taking the preparation of 2 mL of the test sample as an example, the preparation parameters are shown in Table 9.

[0263] Table 9

[0264]

[0265] Positive control 1: Sodium valproate (Shanghai Aladdin Biochemical Technology Co., Ltd., white solid powder, 500g / bottle)

[0266] Preparation of positive control substance 1: Use ultrapure water as solvent for preparation. Take the preparation of 2 mL of the test substance as an example. The preparation parameters are shown in Table 10.

[0267] Table 10

[0268]

[0269] Positive control 2: lithium carbonate (Shanghai Jizhi Biochemical Technology Co., Ltd.; white solid powder; 25g / bottle)

[0270] Preparation of positive control substance 2: Ultrapure water is used as the solvent for preparation. Taking the preparation of 2 mL of the test substance as an example, the preparation parameters are shown in Table 11.

[0271] Table 11

[0272]

[0273] (2) Reagents

[0274] Modeling reagent: Pentylenetetrazol (Sigma-Aldrich (Shanghai) Trading Co., Ltd., white powder)

[0275] Preparation of modeling reagents: Use physiological saline to prepare, taking the preparation of 15 mL of solution as an example, the preparation parameters are shown in Table 12.

[0276] Table 12

[0277]

[0278] Other main reagents:

[0279] Sodium chloride injection (Shandong Qidu Pharmaceutical Co., Ltd., 0.9 g / 100 mL, batch number G124040605)

[0280] (3) Equipment

[0281] Electronic analytical balance: manufacturer METTLLER TOLEDO, model ML2001.

[0282] 4.2 Selection of experimental animals

[0283] SPF grade C57BL / 6j mice were selected and provided by Chengdu Yaokang Biotechnology Co., Ltd.

[0284] 4.3 Animal modeling and grouping

[0285] Modeling time: 1 hour after administration of the test article;

[0286] Model animals: animals from all groups;

[0287] Modeling method: One hour after oral administration of the test sample, pentylenetetrazol (60 mg / kg, 10 mL / kg) was injected intraperitoneally.

[0288] Group design: model control group, sodium valproate group, lithium carbonate group, lithium valproate group;

[0289] Number of animals: 48 in total, 12 in each group;

[0290] Sex ratio: All males;

[0291] Grouping method: Random numbers were assigned according to the weight of mice, and the random numbers were then sorted in descending order. Groups 1, 2, 3, and 4 were set from low to high, representing the model control group, valproate sodium lithium valproate group, lithium carbonate group, and lithium valproate group, respectively. The specific grouping information is shown in Table 13.

[0292] Table 13

[0293]

[0294] In Table 13, the first digit of the animal number represents the group (1, 2, 3, 4, respectively, represent the model control group, sodium valproate group, lithium carbonate group, and lithium valproate group). The second letter represents the sex (M represents male), and the last three digits represent the animal serial number, and "-" represents not applicable.

[0295] For dosage, concentration, and volume, see Table 13;

[0296] Dosing frequency and cycle: once a day;

[0297] The day of drug administration was defined as day 1 (D1) of the experiment.

[0298] 4.4 Animal status monitoring

[0299] (1) General status observation

[0300] Observation time: once a day;

[0301] Observed animals: All surviving animals enrolled in the study;

[0302] Observation content: The main observation contents include but are not limited to the administration site (whether there are symptoms such as redness, swelling, bleeding, etc.), behavioral status, eyes, mouth, nose and mouth, ears, hair, feces, urine, genitals and other symptoms.

[0303] (2)Weight

[0304] Determination time: weigh at least twice during the adaptation period and once before administration;

[0305] Test animals: All animals in the adaptation period and all animals in the experimental period.

[0306] (3) Epilepsy grade score

[0307] Test animals: All groups of animals;

[0308] Detection time: immediately after modeling;

[0309] Detection method: After the injection of PTZ, the mice were immediately placed in a transparent glass cylinder, and the animal behavior was observed and recorded for 30 minutes, and the video was recorded. The latency of epileptic seizures, the number of seizures within 30 minutes, the total duration of seizures within 30 minutes, the highest Racine grade of seizures, and the Racine epilepsy grading evaluation criteria were recorded as shown in Table 14.

[0310] Table 14

[0311]

[0312] 4.5 Experimental Results

[0313] (1) General status observation

[0314] Animals During the experiment, all animals showed no obvious abnormalities.

[0315] (2)Weight

[0316] The weight data of mice are shown in Table 15. The weight of mice in each group increased steadily throughout the experimental period, with a consistent growth trend and no significant difference.

[0317] Table 15 Animal weight data

[0318]

[0319] The data in Table 15 are expressed as mean ± standard deviation (SD).

[0320] (3) Epileptic seizures

[0321] A single high-dose administration of pentylenetetrazol induces acute epileptic seizures in animals. In this experiment, all mice had grade 5 epileptic seizures after injection of pentylenetetrazol, with an attack rate of 100%. Therefore, the anti-epileptic effect of each drug can be reflected by statistically analyzing the latency of grade 5 seizures in each group of mice. The latency of grade 5 epilepsy in mice is shown in Table 16. According to Table 16, after injection of pentylenetetrazol, the latency of grade 5 epilepsy in each group of mice was 123.0±25.5s in the model control group, 178.6±73.0s in the sodium valproate group, 142.5±40.7s in the lithium carbonate group, and 255.6±190.3s in the lithium valproate group. Among them, sodium valproate can prolong the average latency of grade 5 epilepsy in mice by about 50s, lithium carbonate can prolong the average latency of grade 5 epilepsy in mice by about 20s, and lithium valproate can prolong the average latency of grade 5 epilepsy in mice by about 130s.

[0322] The above results show that lithium valproate can significantly delay grade 5 epileptic seizures caused by pentylenetetrazol, and at the same dose, its effect is better than sodium valproate and lithium carbonate.

[0323] Table 16 Epileptic seizure latency

[0324]

[0325] The data in Table 16 are expressed as mean ± standard deviation (SD).

[0326] Example 5 Study on the rapid antidepressant effect of lithium valproate

[0327] 5.1 Selection of experimental animals

[0328] 42 SPF C57BL / 6J mice (male, 7 weeks old). (Manufacturer: Zhejiang Weitonglihua Experimental Animal Technology Co., Ltd., License No.: SCXK(Su)2023-0009), feeding conditions (normal feed, temperature 20-26℃, humidity 40%-70%)

[0329] The interests of animals are fully considered during transportation, feeding, modeling and killing. Animals are treated kindly, stress, pain and harm to animals are prevented or reduced, animal life is respected, brutal behavior against animals is prohibited, and animals are treated in the least painful way. The methods and purposes of animal experiments are in line with human ethical standards and international practices.

[0330] 5.2 Experimental Materials

[0331] (1) Experimental reagents and instruments see Tables 17-18

[0332] Table 17 Reagent information

[0333]

[0334] Table 18 Main instrument information

[0335]

[0336] (2) Reagent preparation method

[0337] Preparation of 0.1mg / ml corticosterone drinking water: weigh 420mg of corticosterone and add 42ml of anhydrous ethanol. Stir at 1000r / min magnetic stirring until dissolved, then add 4158ml of pure water and use in a dark place.

[0338] Preparation of fluoxetine (10 mg / kg, 10 ml / kg, 1 mg / ml): Take 125 mg of CMC-Na and add it to 25 ml of pure water. Stir magnetically until dissolved. Then add 25 mg of fluoxetine and stir magnetically until dissolved (2000 r / min).

[0339] The lithium valproate powder prepared in Example 1 was used to prepare low, medium and high dose groups.

[0340] Preparation of low doses (45.5 mg / kg, 10 ml / kg, 4.55 mg / ml): weigh 53.9 mg of lithium valproate and add 11.84 ml of pure water to fully dissolve.

[0341] Preparation of medium dose (90.1 mg / kg, 10 ml / kg, 9.01 mg / ml): weigh 98.6 mg of lithium valproate and add 10.94 ml of pure water to fully dissolve.

[0342] Preparation of high dose (135.2 mg / kg, 10 ml / kg, 13.52 mg / ml): weigh 142.4 mg of lithium valproate and add 10.53 ml of pure water to fully dissolve.

[0343] 5.3 Animal modeling and grouping

[0344] (1) Animal grouping

[0345] Normal control group (no intervention) (N=8)

[0346] Model + vehicle group (test substance vehicle treatment, oral administration, once / rabbit / day, continuous treatment and administration for 12 days) (N=6 rats)

[0347] Model + positive drug group (fluoxetine treatment, dose: 10 mg / kg, oral administration, once / animal / day, continuous treatment and administration for 12 days) (N=7 animals)

[0348] Model + low dose-test drug group (treated with the test compound, dose: 45.5 mg / kg, intragastric administration, once / animal / day, continuous treatment and administration for 12 days) (N=7 animals)

[0349] Model group + medium dose-test drug group (treated with the test compound, dose: 90.1 mg / kg, intragastric administration, once / rat / day, continuous treatment and administration for 12 days) (N=7 rats)

[0350] Model group + high-dose-test drug group (treated with the test compound, dose: 135.2 mg / kg, intragastric administration, once / rat / day, continuous treatment and administration for 12 days) (N=7 rats)

[0351] (2) Animal modeling

[0352] After adaptive feeding, all animals were weighed. The normal control group was not stimulated and given normal drinking water. All mice except the normal control group were housed in single cages and given 0.1 mg / ml corticosterone in drinking water and chronic unpredictable mild stimulation. The specific time schedule is shown in Tables 3 and 4. Model verification began on the 27th day of modeling, including tail suspension test, forced swimming test and open field test.

[0353] 5.4 Animal experiments

[0354] After the model was successfully established, the mice were treated in groups according to 5.3. Except for the blank control group, which did not receive any intervention, the other groups were treated with corresponding drugs (solvent, positive drug, low, medium, and high doses of test drugs) by gavage, once per animal per day, for 12 consecutive days, and the modeling intervention was maintained during the treatment. Behavioral experiments were performed 24 hours after the 10th treatment, including tail suspension test, open field test, sugar water preference test, and forced swimming test.

[0355] (1) Tail suspension test

[0356] Tail suspension test was performed on D27 of modeling and D9 of treatment. A 3 cm long wooden stick was tied at the base of the tail to prevent the animal from climbing the tail. The tip of the tail was fixed so that the mouse was in an upside-down state for 6 minutes. The immobility time of each mouse in the last 4 minutes was recorded. The immobility time refers to the duration of time when the animal stops struggling and all four limbs are immobile.

[0357] (2) Forced swimming

[0358] Forced swimming test was performed on D28 of modeling and D15 of treatment. The animals were placed in a plastic basket (30 cm long, 20 cm wide, 15 cm high, 10 cm deep) filled with water and forced to swim for 6 min. The KEMaze animal behavior video analysis software system was used to automatically record and analyze the activity status of the mice within 6 min, and the cumulative immobility time of the animals was counted (immobility means that the mice stopped struggling or the mice were floating, and the mice had slight movements of their limbs to keep their heads above the water). Note that the water was changed after each animal test to remove the influence of other mouse odors.

[0359] (3) Open field test

[0360] Open field experiments were performed on D30 of modeling and D10 of treatment. The animals were placed in the central area of ​​the open field box and allowed to move freely in the experimental box for 1 minute. The KEMaze animal behavior video analysis software system was used to automatically record and analyze the activity status and movement trajectory of the mice within 5 minutes. The open field box was cleaned before each experiment to prevent the remaining information of the animals (such as urine, feces, and odor) from affecting the results of the next test.

[0361] (4) Sugar water preference test

[0362] Sugar water preference test was conducted from D10 to D13 of treatment. All animals started sugar water preference training on D10, and all animals were given 2 bottles of 3% sugar water (100 ml / bottle); all animals were given 1 bottle of 3% sugar water and 1 bottle of pure water (100 ml / bottle) on D11, and the positions of the water bottles were swapped at around 11:00, 14:00, and 18:00; all animals began fasting and water deprivation on D12, which lasted for 24 hours; after the end of fasting and water deprivation on D13, the sugar water preference experiment officially began, and all animals were given 1 bottle of 3% sugar water and 1 bottle of pure water (100 ml / bottle), and the initial weights of the two water bottles were recorded. The positions of the water bottles were swapped at 17:30, 9:00 the next day, and 12:00 the next day. The sugar water experiment ended after 24 hours, and the remaining weights of the two water bottles were weighed and recorded to calculate the sugar water preference index.

[0363] 5.5 Experimental Results

[0364] 5.5.1 Evaluation of mouse depression model

[0365] (1) Changes in body weight during modeling

[0366] Figure 8 The figure is a graph showing the weight changes of mice during the modeling of the mouse depression model in Example 5. Figure 8 It can be found that the body weight of the model group was significantly lower than that of the normal group.

[0367] (2) Tail suspension behavior experiment on depressed mice

[0368] Fig. 9 This is a statistical graph of the immobility time in the tail suspension experiment of the mouse depression model in Example 5 (***p<0.001, compared with the normal group). In the tail suspension experiment, the total immobility time of the model group was significantly higher than that of the normal group (P<0.001).

[0369] (3) Open field behavior experiment on depressed mice

[0370] Fig.10This is a statistical diagram of the open field experiment data of the mouse depression model in Example 5. In the open field experiment, the total distance and average speed of the model group were significantly reduced (P<0.001), and the immobility time was significantly increased (P<0.001).

[0371] According to the results of the above body weight, tail suspension test and open field test, the model was successfully established.

[0372] 5.6.2 Evaluation of the efficacy of test drugs

[0373] (1) Effects of test drugs on sugar preference behavior of depressed mice

[0374] Fig.11 The figure is a statistical graph of the sugar preference rate of the mouse depression model in Example 5 affected by the test drugs. In the sugar preference test, compared with the control group, the sugar preference rate of the model group mice was significantly decreased (P<0.01), the decrease rate was 15.6%, and the positive drug and low-dose test drug groups had no obvious effect on sugar preference. The medium and high-dose test drug groups had a significant increase in sugar preference after treatment. The sugar preference of the medium-dose group was 8.2% higher than that of the model group, and the high-dose group was increased by 10.1%, indicating that the medium and high-dose groups had increased pleasure experience and alleviated depression symptoms.

[0375] (2) Effects of the test drugs on the behavior of mice with depression in the tail suspension test

[0376] Fig.12 The figure is a statistical chart of the immobility time of the tail suspension test of the mouse depression model under the influence of the test drug in Example 5. In the tail suspension test, the total immobility time of the model group was higher than that of the normal group, increasing by 43.4%. Due to the abnormality of individual mice, the intra-group differences were large and there was no significant difference. The average immobility time of the positive drug group and the high-dose test drug group was lower than that of the model group. The immobility time of the positive drug decreased by 9.2%, and the immobility time of the high-dose test drug group decreased by 18.5%, indicating that the test drug can shorten and change the "immobility state", and the effect is stronger than that of the positive drug group.

[0377] (3) Effects of test drugs on forced swimming behavior of depressed mice

[0378] Fig.13 The results of the forced swimming behavior of the mouse depression model under the influence of the test drugs in Example 5. In the forced swimming, compared with the model group, the immobility time of the positive drug group was significantly reduced, with a decrease rate of 9.5%, and the immobility time of the low, medium and high dose groups was also significantly reduced, with a decrease rate of 4.2%, 11.2% and 15.8%, indicating that the therapeutic effect of the medium and high dose groups is better than that of the positive drug group.

[0379] Fig.14The results of the open field behavior of the mouse depression model in Example 5 affected by the test drug. In the open field experiment, the total distance and average speed of the model group were significantly reduced (P<0.001), and the immobility time was significantly increased (P<0.001), while the positive drug and the test drug had no significant effect on the depression mice after treatment. The open field test is an important experiment to evaluate anxiety and exploratory behavior, and the efficacy of positive drugs and test drugs is mainly reflected in anti-depression, and the dosage of anxiety and depression is different. The dosage used in this experiment is calculated based on the clinical dosage for the treatment of depression, so it has no significant effect on the various indicators of the open field experiment.

[0380] From the behavioral results after treatment, it can be seen that the test drug has an improving effect on the depressive behavior of mice, reduces the immobility time of tail suspension and forced swimming, and increases the preference rate for sugar water. The effect of high-dose test drugs is significantly better than that of positive drugs.

[0381] In summary, the above experimental results show that the lithium valproate of the present application has a better antidepressant effect than positive drugs, and the lithium valproate of the present application also has a rapid antidepressant effect.

[0382] Example 6 Experiment on the anti-agitation effect of lithium valproate on MK801

[0383] 6.1 Experimental Materials

[0384] (1) Drug testing

[0385] The lithium valproate prepared in Example 1 was used to carry out the MK801-induced anti-agitation experiment.

[0386] Ultrapure water was used as the solvent for preparation. Taking the preparation of 2 mL of the test sample as an example, the preparation parameters are shown in Table 19.

[0387] Table 19

[0388]

[0389] (2) Reagents

[0390] Modeling reagent: (+)-MK-801 hydrogen maleate (MK801) (Sigma-Aldrich (Shanghai) Trading Co., Ltd., white powder)

[0391] Preparation of modeling reagents: Use physiological saline to prepare, taking the preparation of 10 mL of solution as an example, the preparation parameters are shown in Table 20.

[0392] Table 20

[0393]

[0394] Other main reagents:

[0395] Sodium chloride injection (Shandong Qidu Pharmaceutical Co., Ltd., 0.9 g / 100 mL, batch number G124040605)

[0396] (3) Equipment

[0397] For device information, see Table 21.

[0398] Table 21

[0399]

[0400] 6.2 Selection of experimental animals

[0401] SPF grade C57BL / 6j mice were selected and provided by Chengdu Yaokang Biotechnology Co., Ltd.

[0402] 6.3 Animal modeling and grouping

[0403] Modeling time: 1 hour after administration of the test article;

[0404] Model mice: model group, low-dose group, medium-dose group, and high-dose group;

[0405] Modeling method: 4 mice were grouped into a group (one mouse each in the model group, low-dose group, medium-dose group, and high-dose group). MK-801 (0.3 mg / kg, 10 mL / kg) was injected intraperitoneally 1 hour after the test sample was administered orally. After the injection, the mice were directly placed in the open field for open field testing, recorded, and the spontaneous activities of the mice were observed and recorded within 2 hours. After all modeling mice were tested, the mice in the normal control group were tested.

[0406] Group design: normal control group, model control group, low-dose group, medium-dose group, and high-dose group;

[0407] Number of animals: 30 in total, 6 in each group;

[0408] Sex ratio: All males;

[0409] Grouping method: Random numbers were assigned according to the weight of mice, and the random numbers were then sorted in descending order. Groups 1, 2, 3, 4, and 5 were set from low to high, representing the normal control group, model control group, and three test article dosage groups, respectively. The specific grouping information is shown in Table 22.

[0410] Table 22

[0411]

[0412] In Table 22, the first digit of the animal number represents the group (1, 2, 3, 4, and 5 represent the normal control group, model control group, low-dose group, medium-dose group, and high-dose group, respectively). The second letter represents the sex (M represents male), and the last three digits represent the animal serial number, and "-" represents not applicable.

[0413] The dosage, concentration, and volume are all shown in Table 23;

[0414] Dosing frequency and cycle: once a day;

[0415] The day of drug administration was defined as day 1 (D1) of the experiment.

[0416] 6.4 Animal status monitoring

[0417] (1) General status observation

[0418] Observation time: once a day;

[0419] Observed animals: All surviving animals enrolled in the study;

[0420] Observation content: The main observation contents include but are not limited to the administration site (whether there are symptoms such as redness, swelling, bleeding, etc.), behavioral status, eyes, mouth, nose and mouth, ears, hair, feces, urine, genitals and other symptoms. If any abnormalities are found, a detailed description is required.

[0421] (2)Weight

[0422] Determination time: weigh at least twice during the adaptation period and once before administration;

[0423] Test animals: All animals in the adaptation period and all animals in the experimental period.

[0424] (3) Open field test

[0425] Test animals: All groups of animals;

[0426] Detection time: immediately after modeling;

[0427] Detection method: The experiment was conducted in a quiet environment. The mice moved in an open field box. The bottom was divided into a central area and a peripheral area. A camera was placed on the top of the center and connected to the recording system. At the beginning of the experiment, the mice were placed in the central area, and the movement trajectory and spontaneous activities of the mice were recorded within 2 hours. After the recording of a batch of mice experiments was completed, the feces and urine were cleaned, and the bottom and surrounding of the plastic box were thoroughly cleaned with Sanisol. After ventilation and drying, the next batch of animals were tested to prevent odor interference.

[0428] 6.5 Experimental Results

[0429] (1) General status observation

[0430] Animals During the experiment, all animals showed no obvious abnormalities.

[0431] (2)Weight

[0432] The weight data of mice are shown in Table 25. The mice in each group grew steadily throughout the experimental period, with a consistent growth trend and no significant difference. The results showed that intragastric administration of lithium valproate had no significant effect on the weight of mice.

[0433] Table 23 Animal weight data

[0434]

[0435] The data in Table 23 are expressed as mean (Mean) ± standard deviation (SD).

[0436] (3) Open-field spontaneous activity

[0437] After a single dose of MK-801, animals will show hyperactivity, which can simulate the positive symptoms of schizophrenia agitation. The duration of action is 2 hours. Therefore, the open field test of the activity distance of mice within 2 hours after the injection of MK-801 reflects the hyperactivity of mice. Fig.15 , Fig.15 The statistical results of the effect of lithium valproate on the movement distance of model animals in Example 5 are as follows: Fig.15 A in the middle is the distance that each group of mice moved every 10 minutes after the injection of MK-801 during the experiment. A total of 120 minutes were recorded, i.e., the movement distance of the mice in 12 10-minute periods. Fig.15 B is the total movement distance of mice in each group within 120 minutes. Fig.15 All data are expressed as mean ± standard error (SEM).

[0438] according to Fig.15, within 10 minutes after the injection of MK-801, the mice in the model group had shown hyperactivity, and the movement distance was higher than that of the normal control group; the hyperactivity peaked at about 50-80 minutes after the injection; after 80 minutes, the efficacy of MK-801 gradually decreased, and the movement distance of the mice in the model group also gradually decreased; the total movement distance of the mice in the model group within two hours after modeling was significantly increased compared with the normal control mice. The mice in each valproate administration group did not show hyperactivity within 20 minutes after the injection of MK-801, and the movement distance was close to that of the mice in the normal control group. Only after 20 minutes of MK-801 injection did they gradually show hyperactivity, and the movement distance within every 10 minutes was lower than that of the model group. 80 minutes after the injection of MK-801, as the efficacy of MK-801 gradually decreased, the movement distance of the mice in the medium-dose and high-dose groups of lithium valproate gradually approached and finally equaled that of the model group, and the movement distance of the low-dose group of lithium valproate within each 10 minutes during the test period was lower than that of the mice in the model group. The total movement distance of mice in each dose group of lithium valproate within two hours after modeling was reduced to a certain extent compared with the model control mice, but the total movement distance between each dose group was similar.

[0439] The above results show that lithium valproate can delay the onset of hyperactivity caused by MK-801 to a certain extent, reduce the degree of hyperactivity by about 20%, and the efficacy has no obvious dose dependence.

[0440] All documents mentioned in this application are cited as references in this application, just as each document is cited as reference separately. Unless they conflict with the application purpose and / or technical solution of this application, the cited documents involved in this application are cited with all contents and all purposes. When the cited documents are involved in this application, the definitions of relevant technical features, terms, nouns, phrases, etc. in the cited documents are also cited. When the cited documents are involved in this application, the examples and preferred methods of the cited relevant technical features can also be incorporated into this application as references, but are limited to the implementation of this application. It should be understood that when the cited content conflicts with the description in this application, the present application shall prevail or be modified adaptively according to the description of this application.

[0441] The technical features of the above implementation modes and examples can be combined in any appropriate manner. To make the description concise, not all possible combinations of the technical features in the above implementation modes and examples are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0442] The above embodiments only express several implementation methods of the present application, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for those of ordinary skill in the art, without departing from the concept of the present application, several variations and improvements can also be made, which all belong to the protection scope of the present application. In addition, it should be understood that after reading the above-mentioned teaching content of the present application, those skilled in the art can make various changes or modifications to the present application, and the equivalent forms obtained also fall within the protection scope of the present application. It should also be understood that the technical solutions obtained by those skilled in the art, on the basis of the technical solutions provided in the present application, through logical analysis, reasoning or limited experiments, are all within the protection scope of the claims attached to the present application. Therefore, the protection scope of the patent of the present application shall be based on the attached claims, and the specification can be used to interpret the content of the claims.

Claims

1. A lithium valproate, the structure of which is as follows:

2. The lithium valproate according to claim 1, characterized in that The lithium valproate is the lithium salt of valproic acid, wherein the chemical ratio of valproic acid to lithium is 1:

1.

3. The lithium valproate according to claim 2, characterized in that The lithium salt of valproic acid is a crystalline salt.

4. A method for preparing lithium valproate, comprising the steps of: After mixing valproic acid, lithium hydroxide and an aqueous solution of alcohol at 0° C. to 10° C., a first solution is obtained; Stirring the first solution at 20° C. to 40° C. for 12 h to 20 h to obtain a second solution; Filtering the second solution to collect solids to obtain the lithium valproate; The structure of the lithium valproate is as follows:

5. A crystal form of lithium valproate according to any one of claims 1 to 3, characterized in that: Select from any of the following groups: (1) Form I: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.710±0.2°, 7.853±0.2°, 21.674±0.2°, 19.067±0.2°, 20.070±0.2°, 23.617±0.2°, 20.445±0.2° and 15.699±0.2°; (2) Form II: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.660±0.2°, 7.503±0.2°, 18.813±0.2°, 19.522±0.2°, 20.058±0.2°, 22.453±0.2°, 22.729±0.2° and 15.093±0.2°; (3) Form III: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.703±0.2°, 7.869±0.2°, 21.636±0.2°, 23.632±0.2°, 19.080±0.2°, 20.054±0.2°, 15.713±0.2° and 27.420±0.2°; (4) Form IV: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.753±0.2°, 7.883±0.2°, 19.169±0.2°, 21.880±0.2°, 20.263±0.2°, 23.716±0.2°, 15.755±0.2° and 10.930±0.2°; (5) Form V: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.741±0.2°, 7.914±0.2°, 21.680±0.2°, 23.673±0.2°, 19.134±0.2°, 20.094±0.2°, 15.756±0.2° and 10.847±0.2°; (6) Form VI: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.784±0.2°, 7.946±0.2°, 21.743±0.2°, 19.152±0.2°, 23.707±0.2°, 20.502±0.2°, 20.150±0.2° and 21.164±0.2°; and, (7) Form VII: Its X-ray powder diffraction pattern includes the following characteristic diffraction peaks at 2θ (°): 6.729±0.2°, 7.702±0.2°, 18.991±0.2°, 20.702±0.2°, 21.741±0.2°, 22.051±0.2°, 22.533±0.2° and 28.957±0.2°.

6. The crystalline form of lithium valproate according to claim 5, characterized in that: Has at least one of the following characteristics: (1) The differential scanning calorimetry curve of the crystalline form I has an endothermic peak at 359.2±3°C; (2) The differential scanning calorimetry curve of the Form II has an endothermic peak at 361.8±3°C; (3) The differential scanning calorimetry curve of the Form III has an endothermic peak at 331.8±3°C; (4) The differential scanning calorimetry curve of the Form V has an endothermic peak at 357.2±3°C; (6) The differential scanning calorimetry curve of the crystalline form VI has an endothermic peak at 362.3±3° C.; and (7) The differential scanning calorimetry curve of the crystalline form VII has an endothermic peak at 362.2±3°C.

7. A method for preparing the crystal form of lithium valproate according to claim 5 or 6, characterized in that: The steps include: Take lithium valproate and crystallize it by at least one of dissolution crystallization, anti-solvent crystallization, evaporation crystallization, volatilization crystallization and melt crystallization; wherein the solvent used includes at least one of ethanol, dichloromethane, acetonitrile, ethyl acetate, tetrahydrofuran, methanol, petroleum ether, butyl acetate, methyl tert-butyl ether, n-butanol, dimethyl sulfoxide, tert-butanol, isopropanol, toluene and N,N-dimethylformamide.

8. A pharmaceutical composition, characterized in that The pharmaceutical composition comprises a pharmaceutically active ingredient and at least one of a pharmaceutically acceptable excipient and a carrier; The active pharmaceutical ingredient includes lithium valproate; The structure of the lithium valproate is as follows:

9. Use of the lithium valproate according to any one of claims 1 to 3 or the pharmaceutical composition according to claim 8 in the preparation of drugs for treating and / or preventing nervous system diseases.

10. The use according to claim 9, characterized in that The neurological disease includes at least one of epilepsy, mania, schizophrenia, bipolar disorder, anxiety, depression and agitation.

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