A water-soluble estranolone derivative, a preparation method and use thereof

Abstract

The present application relates to the field of medicine, specifically relates to a kind of formula I shown compound, its racemic body, stereoisomer, tautomer, solvate, polymorph or their pharmaceutically acceptable salt:Wherein:R2,R4 respectively independent from H or D;R1,R3 respectively independent from CH3,CH2D,CHD2 Or CD3;Formula I compound contains at least one deuterium atom.The present application is under the premise of retaining allopregnanolone pharmacological activity, by the structure modification of the hydroxyl group of allopregnanolone obtains the allopregnanolone derivative suitable for oral administration, it has good physical / chemical stability.

Description

[0001] This application claims priority to the prior application of Patent Application No. 202111084187.4, filed with the China National Intellectual Property Office on September 14, 2021, and entitled “A Water-soluble Allopregnanolone Derivative, Preparation Method Thereof and Use Thereof”. The entire contents of the prior application are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the field of medicine, in particular to a water-soluble allopregnanolone derivative suitable for oral administration, a preparation method and uses thereof, a pharmaceutical composition comprising the same and uses thereof for preventing or treating central nervous system disorders, sedation and hypnosis, treating Alzheimer's disease, treating epilepsy or treating depression, particularly postpartum depression. BACKGROUND

[0003] Neuroactive steroids are steroids active in neural tissue, which play an important regulatory role in the human body. Neuroactive steroids mainly include progesterone, pregnenolone and progesterone metabolite allopregnanolone. The synthesis of neuroactive steroids in the body is impaired, which can lead to different neurological (CN 104736158A) or mental disorders (Expert Opin Ther Targets. 2014; 18(6): 679-90).

[0004] At present, it is generally believed that the allopregnanolone substances include the following compounds: allopregnanolone, allo-tetranolone, epiallopregnanolone and isopregnanolone (see Table 1).

[0005] Table 1: Names of allopregnanolone

[0006] Common Name IUPAC Name Pregnanolone 3α-OH-5β-pregnan-20-one Allopregnanolone 3α-OH-5α-pregnan-20-one Epipregnanolone 3β-OH-5β-pregnan-20-one Iso-pregnanolone 3β-OH-5α-pregnan-20-one Allopregnanolone 3α-OH-5β-pregnan-21-ol-20-one Iso-pregnanolone 3β-OH-5α-pregnan-21-ol-20-one

[0007] Patent document CN1300219A discloses that different allopregnanolone substances have different mechanisms of action in the regulation of the central nervous system and have different physiological effects on the central nervous system. Allo-tetranolone (3α-OH-5α-pregnane-20-one) is an important GABAA (gamma-aminobutyric acid A) receptor, which has the effects of anti-epilepsy, hypnotic, anti-migraine and anti-anxiety. Epiallopregnanolone (3β-OH-5α-pregnane-20-one) can block and antagonize the effects of allo-tetranolone, appropriately control and terminate the anesthesia caused by allo-tetranolone, etc.

[0008] Allopregnanolone (3a-OH-5a-pregnane-20-one) is a hot spot of research in recent years. As early as 1986, it has been pointed out that allopregnanolone is a positive modulator of GABAA receptor. Allopregnanolone may mainly bind to the a and b subunits of the GABAA receptor, increase the opening frequency of the chloride channel on the receptor, and reduce the nerve excitability, thereby producing calming and anti-anxiety effects.

[0009] It has been reported that the levels of progesterone and its metabolites in the body are different at different stages of the menstrual cycle. Before the start of menstruation, the levels of progesterone and its metabolites decrease, which can cause premenstrual syndrome (PMS), i.e. some symptoms repeatedly occur before the start of the menstrual cycle, which disappear after the menstrual period, such as stress, anxiety and migraine (Dalton, K., Premenstrual Syndrome and Progesterone Therapy, Second Edition, Chicago Yearbook, Chicago (1984)). Postpartum depression is also related to abnormal levels of progesterone and its metabolites. As pregnancy progresses, the concentration of allopregnanolone in the plasma of healthy pregnant women increases, and after delivery, the concentration of allopregnanolone decreases sharply. Studies have shown that the decrease in allopregnanolone content is closely related to the occurrence and development of many mental disorders such as anxiety, depression and tremor, and exogenous administration of allopregnanolone can significantly improve the above mental symptoms.

[0010] However, the existing allopregnanolone has low water solubility, poor oral bioavailability, a plasma half-life of about 45 minutes, and can be rapidly metabolized, which is not conducive to the preparation of oral preparations.

[0011] Patent document CN104736158A discloses a method of preparing allopregnanolone and cyclodextrin into a composition and intravenously infusing the composition to treat epilepsy or persistent epilepsy. In the composition of allopregnanolone and cyclodextrin, the proportion of cyclodextrin is 1-30%, the blood drug concentration is 50-2300 nM, and the treatment process lasts for more than 24 hours. However, cyclodextrin is a high molecular compound, which has a certain risk of kidney toxicity (Safety Research on Pharmaceutical Supramolecular Material Cyclodextrin Derivatives, China Materials Science and Technology and Equipment, No. 5, 2009, pp. 1-3), thus there is a safety hazard.

[0012] In 2019, SAGE Therapeutics' allopregnanolone injection was approved for marketing in the United States under the trade name ZULRESSO. Allopregnanolone injection is a sterile, clear, colorless, and preservative-free intravenous injection preparation. It forms an inclusion compound of allopregnanolone with sulfobutyl beta-cyclodextrin sodium to improve the solubility of allopregnanolone. Allopregnanolone injection produces stable, physiological concentrations of allopregnanolone through intravenous injection to achieve therapeutic effect, but it requires a long intravenous infusion of 60 hours, and the infusion method is complex. During the infusion, professional medical personnel need to conduct continuous on-site monitoring and necessary intervention. This leads to poor patient compliance of allopregnanolone injection and extremely inconvenient use of medical personnel. The infusion method of allopregnanolone injection is as follows: 0-4h: infusion at a dose of 30μg / kg / h; 4-24h: increase the dose to 60μg / kg / h; 24-52h: increase the dose to 90μg / kg / h (for patients who cannot tolerate 90μg / kg / h, the dose can also be considered as 60μg / kg / h); 52-56h: reduce the dose to 60μg / kg / h; 56-60h: reduce the dose to 30μg / kg / h. SUMMARY

[0013] The present application aims to provide an allopregnanolone derivative suitable for oral administration, high bioavailability, rapid onset of action, and long-term maintenance of stable physiological concentration in vivo.

[0014] The present application also aims to provide a composition comprising an allopregnanolone derivative and the use of the above-mentioned allopregnanolone derivative in the preparation of a medicament for treating diseases caused by abnormalities in the central nervous system.

[0015] The present application is achieved by the following technical solutions,

[0016] In a first aspect, the present application provides a compound of general formula I, its racemate, stereoisomer, tautomer, solvate, polymorph, or a pharmaceutically acceptable salt thereof:

[0017]

[0018] wherein:

[0019] R2, R4 are each independently selected from H (hydrogen) or D (deuterium);

[0020] R1, R3 are each independently selected from CH3, CH2D, CHD2, or CD3;

[0021] with the proviso that the compound of formula I contains at least one deuterium atom.

[0022] In some embodiments of the application, the compound of formula I contains one to eight deuterium atoms, or the compound of formula I contains one to seven deuterium atoms, or the compound of formula I contains one to six deuterium atoms, in particular the compound of formula I contains at least one, two, three, four, five, six, seven or eight deuterium atoms.

[0023] In some embodiments of the application, R2 is D.

[0024] In some embodiments of the application, R2 is D, and R1 and R3 are CH3.

[0025] In some embodiments of the application, R2 is D, and R1 and R3 are CD3.

[0026] According to embodiments of the application, the deuterium enrichment of each D is at least 3500 times (52.5%), preferably at least 4000 times (60%), preferably at least 4500 times (67.5%), more preferably at least 5000 times (75%), more preferably at least 5500 times (82.5%), more preferably at least 6000 times (90%), more preferably at least 6333.3 times (95%), further preferably at least 6466.7 times (97%), further preferably at least 6566.7 times (98.5%), further preferably at least 6600 times (99%), further preferably at least 6633.3 times (99.5%).

[0027] Preferably, any atom not designated as deuterium is present at its natural isotopic abundance.

[0028] In particular embodiments of the application, the compound of formula I is a compound of formula la or lb:

[0029]

[0030] wherein R1, R2, R3, R4 have the definitions as described above.

[0031] In some preferred embodiments of the application, examples of compounds of formula I are as follows:

[0032]

[0033] If the compounds of the present application can exist in tautomeric forms, the present application includes all tautomeric forms.

[0034] The compounds of the present application can exist in stereoisomeric forms (enantiomers, diastereomers). Thus, the present application includes enantiomers or diastereomers and mixtures thereof. The stereoisomeric pure components can be isolated from such mixtures of enantiomers and / or diastereomers in known manner.

[0035] The present application also provides a method for preparing the compound of Formula I, comprising the following steps:

[0036]

[0037] wherein R1-R4 have the meanings as described above, and R5 is a protecting group, for example an amino protecting group, such as tert-butoxycarbonyl (Boc);

[0038] reacting the compound of Formula II with a compound of Formula III, and removing the protecting group to obtain the compound of Formula I.

[0039] The present application also provides a pharmaceutical composition comprising at least one of the compound of Formula I, its racemate, stereoisomer, tautomer, solvate, polymorph, or pharmaceutically acceptable salt thereof.

[0040] According to the present application, the pharmaceutical composition further comprises one or more pharmaceutically acceptable excipients.

[0041] According to the present application, the pharmaceutical composition is for oral administration, and the pharmaceutical composition can be tablets, pills, lozenges, dragees, capsules, etc.

[0042] The pharmaceutical composition of the present application can be manufactured by methods well known in the art, such as the conventional mixing, granulating, dragee-making processes, etc. For example, solid oral compositions can be prepared by the conventional mixing, encap- sulation, or compression processes. For example, solid oral compositions can be obtained by mixing the active compound with a solid excipient, optionally grinding the resulting mixture, and processing the mixture of steps, if desired, to obtain granules. Suitable excipients include, but are not limited to, binders, diluents, disintegrating agents, lubricants, glidants, sweetening, or flavoring agents, etc.

[0043] The present application provides the use of the compound of Formula I of the present application, its racemate, stereoisomer, tautomer, solvate, polymorph, or pharmaceutically acceptable salt thereof, or the pharmaceutical composition of the present application, in the manufacture of a medicament for preventing or treating central nervous system disorders, for sedation and hypnosis, for treating Alzheimer's disease, for treating epilepsy, or for treating depression, particularly postpartum depression.

[0044] The present application provides a method for preventing or treating a central nervous system disorder, sedation and hypnosis, treating Alzheimer's disease, treating epilepsy or treating depression, particularly postpartum depression, comprising administering to a subject in need thereof a prophylactically or therapeutically effective amount of a compound of Formula I, a racemate, stereoisomer, tautomer, solvate, polymorph or pharmaceutically acceptable salt thereof, or a pharmaceutical composition of the present application.

[0045] According to the present application, the central nervous system disease is, for example, traumatic brain injury, essential tremor, epilepsy (including refractory status epilepticus, rare genetic epilepsies (e.g. Dravet syndrome and Rett syndrome), depression (including postpartum depression) and Alzheimer's disease. The central nervous system disease is, for example, selected from essential tremor, epilepsy, clinical depression, postpartum or post-delivery depression, atypical depression, psychotic major depression, catatonic depression, seasonal affective disorder, dysthymia, double depression, depressive personality disorder, recurrent brief depression, minor depressive disorder, bipolar disorder or manic-depressive disorder, post-traumatic stress disorder, depression due to chronic medical conditions, treatment-resistant depression, refractory depression, suicidality, suicidal ideation or suicidal behavior.

[0046] In all methods of administration of the compounds of general formula I described herein, the dose administered per day is between 0.01 and 200 mg / kg of body weight.

[0047] Dosage regimens can be adjusted to provide the optimum desired response. For example, a single dose can be administered, several divided doses can be administered over time or the dose can be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. It is to be noted that dosage values can vary with the type and severity of the condition to be alleviated. It is to be further noted that for any particular individual, specific dosage regimens should be adjusted over time according to the individual need and the professional judgment of the person administering or supervising the administration of the compositions.

[0048] Definitions and Descriptions

[0049] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as those one of ordinary skill in the art to which the application pertains. All patents and publications referred to in this application are incorporated by reference in their entirety.

[0050] Unless otherwise indicated, the following definitions are applied to the terms used herein. When a name of an article appears herein, it is intended to refer to its corresponding article or to its active ingredient, unless otherwise indicated.

[0051] The terms "comprise", "comprising", "have", "having", "include", "including", "contain", "containing", or "involve" and any variations thereof herein are open-ended, and do not exclude additional, unrecited elements or method steps.

[0052] The term "preventing or treating" means that the compounds or formulations described herein are administered to prevent, ameliorate or eliminate a disease or one or more symptoms associated with the disease, and includes:

[0053] (i) preventing the disease or condition from occurring in a mammal, in particular, when such mammal is predisposed or has a predisposition to the disease but has not yet been diagnosed as having it;

[0054] (ii) inhibiting the disease or condition, i.e., arresting its development;

[0055] (iii) relieving the disease or condition, i.e., causing regression of the disease or condition.

[0056] The term "deuterium enrichment" refers to the ratio of the amount of the isotope present in a synthesis to the amount of the isotope present in nature. Unless otherwise specified, when a position in a structure is defined as H, it contains only the amount of the isotope present in nature. When a position in a structure is defined as D, it contains at least 3340 times more of the isotope than is present in nature (i.e., at least 50.1% deuterium isotope).

[0057] The term "therapeutically effective amount" means an amount of a compound of the present application that (i) treats or prevents the particular disease, condition, or disorder, (ii) attenuates, ameliorates, or eliminates one or more symptoms of the particular disease, condition, or disorder, or (iii) prevents or delays the onset of one or more symptoms of the particular disease, condition, or disorder described herein. The amount of a compound of the present application that will constitute a "therapeutically effective amount" will vary depending on the compound, the disease state and its severity, the manner of administration, and the age of the mammal to be treated, but can be determined routinely by the skilled practitioner as an initial consideration.

[0058] The term "pharmaceutically acceptable" in reference to compounds, materials, compositions, and / or dosage forms is used adjectivally to describe a material that is, within the scope of sound medical judgment, suitable for use in contact with the tissues of humans and animals without undue toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit / risk ratio.

[0059] Pharmaceutically acceptable salts of the compounds of the present application include those formed with pharmaceutically acceptable acids and those formed with pharmaceutically acceptable bases.

[0060] The term "pharmaceutically acceptable acid" as used herein refers to pharmaceutically acceptable acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, carbonic acid, formic acid, acetic acid, acetoacetic acid, trifluoroacetic acid, propionic acid, pyruvic acid, butyric acid, hexanoic acid, heptanoic acid, undecanoic acid, lauric acid, stearic acid, palmitic acid, oxalic acid, methanesulfonic acid, trifluoromethanesulfonic acid, ethanedisulfonic acid, hydroxyethanesulfonic acid, 1,5-naphtalene disulfonic acid, 2-naphtalene sulfonic acid, camphorsulfonic acid, sulfamic acid, lactic acid, benzenesulfonic acid, p-toluenesulfonic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, lactic acid, tartaric acid, citric acid, malic acid, benzoic acid, salicylic acid, cinnamic acid, naphthoic acid, pamoic acid, nicotinic acid, orotic acid, methylsulfuric acid, dodecylsulfuric acid, glutamic acid, aspartic acid, gluconic acid, glucuronic acid, or any combination thereof.

[0061] The term "pharmaceutically acceptable base" as used herein refers to pharmaceutically acceptable bases such as inorganic bases (alkali metal or alkaline earth metal hydroxides, etc.) or organic bases (amines such as primary, secondary, or tertiary amines, etc.). Examples of suitable salts include, but are not limited to, organic salts of amino acids, ammonia, primary, secondary, and tertiary amines, and cyclic amines (e.g., diethylamine salts, piperidine salts, morpholine salts, piperazine salts, choline salts, meglumine salts, tromethamine salts, etc.), and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum, and lithium.

[0062] The term "solvate" is a compound of the present application that further includes a complex or a combination that is formed by a coordination adduct between a solvent molecule and a compound of the present application in a solid or liquid state. Hydrates are a specific form of a solvate wherein the coordination is with water.

[0063] The term "pharmaceutical composition" refers to a mixture of one or more compounds of the present application or salts thereof with a pharmaceutically acceptable excipient. The objective of a pharmaceutical composition is to facilitate administration of a compound of the present application to an organism.

[0064] The term "pharmaceutically acceptable excipient" refers to those excipients that are not biologically or otherwise undesirable, and that do not interfere with the biological activity of the active compound. Suitable excipients are well known to those skilled in the art. Examples of suitable excipients are carbohydrates, waxes, water soluble and / or swellable polymers, hydrophilic or hydrophobic materials, gelatin, oils, solvents, water, and the like.

[0065] The pharmaceutical composition of the present application can be prepared by combining a compound of the present application with a suitable pharmaceutically acceptable excipient and, where necessary, other medicinal or pharmaceutical agents, and / or suitable pharmaceutical buffers, etc., and then, where possible, where appropriate, bringing the resulting mixture to the desired form. For oral administration, the pharmaceutical composition can be formulated by mixing the active compound with pharmaceutically acceptable excipients well known in the art, such as citric acids, alcohols, waxes, water soluble and / or swellable polymers, hydrophilic or hydrophobic materials, gelatin, oils, solvents, water, etc.

[0066] As used herein, "individual" includes humans and non-human animals. Exemplary human individuals include human individuals (referred to as patients) having a disease (e.g., a disease described herein) or normal individuals. "Non-human animals" in the present application include all vertebrates, e.g., non-mammals (e.g., birds, amphibians, reptiles), and mammals, e.g., non-human primates, farm animals, and / or domestic animals (e.g., sheep, dog, cat, cow, pig, etc.).

[0067] Beneficial effects

[0068] The present application provides a kind of allopregnanolone derivative shown in formula I, under the premise of retaining allopregnanolone pharmacological activity, by the structure modification of the hydroxyl group of allopregnanolone, obtain suitable allopregnanolone derivative for oral administration, it has good physical / chemical stability.It can release active drug in vivo, thereby exerting pharmacological effect.Allopregnanolone derivative of the present application is metabolically stable, has good oral bioavailability, has small toxic side effect, can quickly take effect after oral administration and maintain stable physiological concentration of allopregnanolone in vivo for a long time, can be made into suitable oral preparation, improve drug safety, improve patient compliance and administration convenience. BRIEF DESCRIPTION OF DRAWINGS

[0069] Figure 1 Pharmacokinetic curve of allopregnanolone in the plasma of male rats after oral administration of the compound of the present application;

[0070] Figure 2 Pharmacokinetic curve of allopregnanolone in the plasma of beagle dogs after oral administration of the compound of the present application. DETAILED DESCRIPTION

[0071] The following will be further described in detail with specific examples of the general compounds of the present application and the preparation method and application thereof. It should be understood that the following examples are only illustratively and explain the present application, and should not be interpreted as limiting the scope of protection of the present application. Any technology realized based on the above content of the present application is covered in the scope intended to be protected by the present application.

[0072] The intermediate compounds of the present application can be prepared by various synthetic methods well known to those skilled in the art, including the specific embodiments listed below, the embodiments formed by the combination of the specific embodiments with other chemical synthesis methods, and the equivalent replacement methods well known to those skilled in the art, and the preferred embodiments include but are not limited to the examples of the present application.

[0073] The chemical reactions of the specific embodiments of the present application are completed in suitable solvents, and the solvents should be suitable for the chemical changes of the present application and the required reagents and materials. In order to obtain the compounds of the present application, sometimes it is necessary for those skilled in the art to modify or select the synthesis steps or reaction schemes on the basis of the existing embodiments.

[0074] The present application will be described in detail by the following examples, which do not mean any limitation of the present application.

[0075] The experimental methods in the following examples, unless otherwise specified, are generally carried out according to the conventional conditions, or according to the conditions suggested by the manufacturers. Unless otherwise specified, percentages and parts are by weight. The raw materials and reagents used in the following examples are commercially available, or can be prepared by known methods.

[0076] The following abbreviations are used in the present application: aq represents aqueous solution; DMSO represents dimethyl sulfoxide; EtOAc represents ethyl acetate; EtOH represents ethanol; TFA represents trifluoroacetic acid; i-PrOH represents isopropyl alcohol; ECS represents extracellular solution; ICS represents intracellular solution; MI001 represents allopregnanolone.

[0077] Comparative Example 1: Preparation of hydrochloride salt of Comparative Compound 1 (C1)

[0078]

[0079] Step 1: Into a 1000 mL three-necked round-bottom flask, MI001 (50.0 g, 157.0 mmol, 1.0 eq), Boc-L-Val-OH (tert-butyloxycarbonyl L-valine) (40.9 g, 188.2 mmol), 4-dimethylaminopyridine (1.9 g, 15.5 mmol) and dichloromethane 500 mL were added, the reaction system was stirred and cooled to -5 to 10 °C under nitrogen protection, a solution of dicyclohexyl carbodiimide (38.9 g, 188.5 mmol) in dichloromethane (80 mL) was added dropwise, then the reaction was carried out at this temperature for 3 hours, the reaction was monitored by TLC (Thin Layer Chromatography) until it was completed, and then the reaction was stopped. The reaction solution was filtered, and the filter cake was washed with dichloromethane (100 mL). The filtrate was concentrated under reduced pressure, and the crude product was purified by column chromatography (100-200 mesh silica gel, petroleum ether (60-90) / ethyl acetate 20:1-10:1) to obtain a white waxy solid (78.2 g, yield 96.2%).

[0080] Step 2: Into a 1000 mL three-necked round-bottom flask, was placed the product from Step 1 (78 g, 150.6 mmol, 1.0 eq) and dichloromethane (320 mL). The system was cooled to 0-10 °C under nitrogen protection and magnetic stirring, and trifluoroacetic acid (171.8 g, 1506 mmol) was added dropwise. The reaction was allowed to proceed at 15-25 °C for 3 hours, and then was quenched by pouring the reaction mixture into a solution of sodium bicarbonate (164.5 g, 1958 mmol) in water (780 mL). Dichloromethane (700 mL) was added, and the mixture was stirred and allowed to separate. The organic phase was obtained. The organic phase was washed with 500 mL of pure water and dried over anhydrous sodium sulfate. Filtration and concentration gave a white solid (59.5 g, 94.6% yield).

[0081] Step 3: To the product described above (0.5 g) was added isopropyl alcohol (0.5 mL) and isopropyl acetate (7.5 mL). The mixture was dissolved at room temperature, and then ethyl acetate hydrochloride solution (0.6 mL, 2.0 M ethyl acetate hydrochloride) was added dropwise. A large amount of solid was precipitated at 5-10 °C. The product (0.36 g) was obtained by filtration and drying, with a yield of 66.5% and a purity of 99.90% by HPLC.

[0082] 1 H NMR (400 MHz, CDC13) δ 8.83 (br s, 3H), 5.23 - 5.14 (m, 1H), 4.00 - 3.88 (m, 1H), 2.52 (t, J = 8.7 Hz, 2H), 2.22 - 2.08 (m, 1H), 2.11 (s, 3H), 2.06 - 1.96 (m, 1H), 1.86 - 1.08 (m, 18H), 1.18 (m, 3H), 1.17 (m, 3H), 1.04 - 0.88 (m, 1H), 0.86 - 0.71 (m, 1H), 0.80 (s, 3H), 0.61 (s, 3H). MS m / z: 418.3 [M+H] + .

[0083] Synthesis of Compound 1 and its hydrochloride salt of Example 1

[0084]

[0085] Synthesis of Intermediate 1a:

[0086] To a 100 mL single neck flask was added Boc-L-Val-OH-3-d (1.20 g, 5.5 mmol), MI001 (1.91 g, 6.0 mmol), 4-dimethylaminopyridine (0.07 g, 0.6 mmol) and dichloromethane (15 mL). A solution of dicyclohexylcarbodiimide (1.24 g, 6.0 mmol) in dichloromethane (5 mL) was added dropwise at 20 °C and stirred overnight. The dicyclohexylurea was removed by filtration and the filtrate was concentrated and purified by column chromatography (petroleum ether / ethyl acetate 20:1-7:1) to give 2.3 g of intermediate 1a as a colourless oil in 80% yield.

[0087] 1 H NMR (400 MHz, CDC13) δ 5.10 (m, 1H), 5.07 (d, J = 9.5 Hz, 1H), 4.23 (d, J = 9.1 Hz, 1H), 2.53 (t, J = 8.8 Hz, 1H), 2.26 - 2.08 (m, 1H), 2.11 (s, 3H), 2.06 - 1.95 (m, 1H), 1.85 - 0.71 (m, 20H), 1.46 (s, 9H), 0.98 (s, 3H), 0.90 (s, 3H), 0.80 (s, 3H), 0.61 (s, 3H).

[0088] Synthesis of compound 1:

[0089] To a 100 mL single neck flask was added intermediate 1a (2.3 g, 4.4 mmol) and dichloromethane (15 mL) and stirred to dissolve at 20 °C. Trifluoroacetic acid (5.02 g, 44.0 mmol) was added dropwise. The reaction was stirred at 15-25 °C for 3-4 hours and dichloromethane (20 mL) was added. The reaction was slowly poured into aqueous sodium bicarbonate solution (15 g / 50 ml) with stirring and left to stand for 5-15 minutes. The organic phase was separated and washed with pure water (50 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated to give 1.73 g of compound 1.

[0090] Synthesis of compound 1 hydrochloride (1'):

[0091] The resulting compound 1 (1.59 g, 3.8 mmol) was dissolved in ethyl acetate (20 mL) and isopropanol (1.3 mL). Hydrogen chloride ethyl acetate solution (2.4 M, 1.6 mL, 3.8 mmol) was added dropwise. The mixture was stirred at 20 °C for 1 hour, filtered and the filter cake was washed with ethyl acetate (20 mL). The white solid was dried at 40 °C under oil pump vacuum (P < -0.09 MPa) for 4 hours to give 1.18 g in 68% yield.

[0092] 1H NMR (400 MHz, CDC13) δ 8.83 (br s, 3H), 5.23 - 5.14 (m, 1H), 4.00 - 3.88 (m, 1H), 2.52 (t, J = 8.7 Hz, 1H), 2.22 - 2.08 (m, 1H), 2.11 (s, 3H), 2.06 - 1.96 (m, 1H), 1.86 - 1.08 (m, 18H), 1.18 (s, 3H), 1.17 (s, 3H), 1.04 - 0.88 (m, 1H), 0.86 - 0.71 (m, 1H), 0.80 (s, 3H), 0.61 (s, 3H). MS m / z: 419.28 [M+H] + .

[0093] Synthesis of compound 2 and its hydrochloride salt of Example 2

[0094]

[0095] Synthesis of intermediate 2a:

[0096] Into a 100 mL three-necked flask, was added Boc-L-Val-OH-d6 (2 g, 8.95 mmol), dichloromethane (30 g), MI001 (2.85 g, 8.95 mmol), 4-dimethylaminopyridine (0.11 g, 0.90 mmol), stirred and cooled to -5-5 °C, added dropwise a solution of dicyclohexylcarbodiimide (2.1 g, 10 mmol) in dichloromethane (7.5 g), after 3 hours of reaction at 15-25 °C, TLC showed that the reaction was complete, the reaction solution was washed with water and stirred to separate the organic phase, which was dried over anhydrous sodium sulfate and concentrated, and then separated by column chromatography (petroleum ether / ethyl acetate = 20:1) to obtain 3.2 g of colorless oil intermediate 2a with a yield of 68.5%.

[0097] Synthesis of compound 2:

[0098] The product 2a obtained in the above step was dissolved in dichloromethane (16 mL), and trifluoroacetic acid (10.7 g) was added, and stirred at 15-25 °C for 3-4 hours, TLC showed that the starting material was completely reacted, the reaction solution was added to an aqueous sodium bicarbonate solution (40 mL), and the pH was adjusted to 7-8, then dichloromethane (10 mL) was added, the organic phase was separated after separation, the aqueous phase was extracted once more with dichloromethane (20 mL), the organic phases were combined, washed with water (5 mL x 3), and then dried over anhydrous sodium sulfate, concentrated to dryness to obtain a solid, which was slurried with acetonitrile (8 mL) and filtered to obtain 1.2 g of compound 2.

[0099] Synthesis of compound 2 hydrochloride salt (2’):

[0100] To compound 2 (0.6 g), isopropanol (0.6 mL) and isopropyl acetate (9 mL) were added and dissolved at room temperature. Then, ethyl acetate hydrochloride solution (0.7 mL, 2.0 M ethyl acetate hydrochloride solution) was added dropwise. A large amount of solid was precipitated at 5-10 °C. The product 0.3 g was obtained by filtration and drying, with a yield of 46.2% and a purity of 99.7% by HPLC.

[0101] 1 H NMR (400 MHz, CDC13) δ 8.85 (br s, 3H), 5.22 (s, 1H), 3.95 (br s, 1H), 2.54 (t, J = 8.7 Hz, 1H), 2.49 (s, 1H), 2.19 - 2.14 (m, 1H), 2.14 (s, 3H), 2.05 - 2.02 (m, 1H), 1.84 - 1.72 (m, 5H), 1.61-1.41 (m, 7H), 1.32-1.17 (m, 6H), 1.04 - 0.88 (m, 1H), 0.85 (m, 1H), 0.82 (s, 3H), 0.63 (s, 3H). MS m / z: 424.39 [M+H] + .

[0102] Synthesis of compound 3 and its hydrochloride salt of Example 3:

[0103]

[0104] Synthesis of intermediate 3a:

[0105] To a 100 mL single-neck flask was added Boc-Val-OH-2-d (1.0 g, 4.6 mmol), MI001 (1.46 g, 4.6 mmol), 4-dimethylaminopyridine (0.06 g, 0.5 mmol) and dichloromethane (15 mL). A solution of dicyclohexylcarbodiimide (0.95 g, 4.6 mmol) in dichloromethane (5 mL) was added dropwise at 20 °C and stirred overnight. Filtration was performed and the filtrate was concentrated. Column chromatography (petroleum ether / ethyl acetate = 20:1-7:1) gave 1.6 g of intermediate 3a as colorless oil with a yield of 56%.

[0106] Synthesis of compound 3:

[0107] The product intermediate 3a obtained in the previous step was dissolved in dichloromethane (8 g), trifluoroacetic acid (4.5 g) was added, and stirring was carried out at 15-25 °C for 3-4 hours. TLC was used to monitor the completion of the reaction of the raw material. The reaction liquid was added to 20 mL of an aqueous sodium bicarbonate solution, the pH was adjusted to 7-8, dichloromethane (5 mL) was further added, the liquid was separated, and the organic phase was retained. The aqueous phase was extracted once more with dichloromethane (10 mL), and the combined organic phase was washed with water (5 mL x 3). After drying over anhydrous sodium sulfate, the organic phase was concentrated to dryness to obtain a solid. The solid was slurried in acetonitrile (4 mL) and filtered to obtain 0.6 g of the free base.

[0108] Synthesis of compound 3 hydrochloride (3’):

[0109] The product compound 3 (0.5 g) was dissolved in isopropyl alcohol (0.5 mL) and isopropyl acetate (7.5 mL) at room temperature, and hydrogen chloride ethyl acetate solution (0.6 mL, 2.0 M hydrogen chloride ethyl acetate solution) was added dropwise. A large amount of solid was precipitated upon cooling to 5-10 °C. The solid was filtered and dried to obtain 0.36 g of the product, with a yield of 66.5% and a purity of 99.70% by HPLC.

[0110] 1 H NMR (400 MHz, CDCl3) δ 8.84 (brs, 3H), 5.21 (s, 1H), 2.56-2.48 (m, 2H), 2.21-2.17 (m, 1H), 2.13 (s, 3H), 2.05-2.02 (m, 1H), 1.83-1.36 (m, 12H), 1.32-1.19 (m, 12H), 1.04-0.95 (m, 1H), 0.90-0.84 (m, 1H), 0.82 (s, 3H), 0.63 (s, 3H). MS m / z: 419.25 [M+H] + .

[0111] Synthesis of compound 4 and its hydrochloride

[0112]

[0113] Compound 4 and its hydrochloride (4’) were prepared according to the synthesis method of Example 1, using MI001 and Boc-D-Val-OH-3-d as raw materials.

[0114] Compound 4 hydrochloride (4’), white solid, 1HNMR (400 MHz, CDC13) δ 8.76 (br s, 3H), 5.16 (br s, 1H), 4.00 - 3.88 (m, 1H), 2.52 (t, J = 8.7 Hz, 1H), 2.22 - 2.08 (m, 1H), 2.08 (s, 3H), 2.06 - 1.96 (m, 1H), 1.86 - 1.08 (m, 18H), 1.18 (s, 3H), 1.17 (s, 3H), 1.04 - 0.88 (m, 1H), 0.86 - 0.71 (m, 1H), 0.79 (s, 3H), 0.61 (s, 3H). MS m / z: 419.35 [M+H] + .

[0115] Synthesis of compound 5 and its hydrochloride salt

[0116]

[0117] Compound 5, the hydrochloride salt of compound 5 (5'), were prepared according to the synthetic method of Example 2, using MI001, Boc-D-Val-OH-d7 as starting material.

[0118] Compound 5 hydrochloride salt (5'), white solid, 1 H NMR (400 MHz, CDC13) δ 8.76 (br s, 3H), 5.16 (br s, 1H), 4.00 - 3.88 (m, 1H), 2.52 (t, J = 8.7 Hz, 1H), 2.22 - 2.08 (m, 1H), 2.08 (s, 3H), 2.06 - 1.96 (m, 1H), 1.86 - 1.08 (m, 18H), 1.18 (s, 3H), 1.17 (s, 3H), 1.04 - 0.88 (m, 1H), 0.86 - 0.71 (m, 1H), 0.79 (s, 3H), 0.61 (s, 3H). MS m / z: 419.35 [M+H] + .

[0119] Test Example 1 Solubility experiment of compound

[0120] 1. Sample preparation

[0121] Preparation of external standard solution: 50 mg of the compound to be tested was accurately weighed into a 10 mL volumetric flask, and a suitable amount of pure water was added to dissolve and dilute to the mark, and then mixed to obtain an external standard solution with a concentration of 5.0 mg / mL.

[0122] Preparation of the test solution: 1.0 g of the test compound was precisely weighed into 20 mL of pure water, stirred and dissolved at 25℃ for 24 h, centrifuged, and the supernatant was filtered through a 0.45 μm filter membrane to obtain a filtrate. 1 mL of the filtrate was precisely measured into a 5 mL volumetric flask, diluted with pure water to the calibration mark, and mixed to obtain the test solution.

[0123] 2. Determination of the saturated solubility by the external standard method

[0124] Chromatographic conditions:

[0125] Chromatographic column: Waters XBridge C8 3.5 μm 4.6*100 mm NRT2019-21#, column temperature: 45℃, detection wavelength: 205 nm;

[0126] Mobile phase A: 10 mM / L (NH4)2HPO4 solution, mobile phase B: acetonitrile, isocratic elution A:B = 40:60, flow rate: 1.0 mL / min;

[0127] Injection volume: 10 μL, run time: 10 min.

[0128] The peak areas of the external standard solution and the standard solution were determined by a high-performance liquid chromatograph with a UV detector, and were denoted as A 外标 and A 待测 , respectively. The saturated solubility C of the test compound was calculated by the following formula: C = A 待测 / A 外标 *5 mg / mL*5. The specific results are shown in Table 2.

[0129] Table 2: Saturated solubility of each substance

[0130]

[0131] Test Example 2: Patch clamp experiment results

[0132] The manual patch clamp method was used to detect the effect of the compound on the hERG potassium channel current stably expressed in Chinese hamster ovary cells. Inhibition of the hERG potassium ion channel by drugs is the main cause of prolonged myocardial repolarization, and the greater the hERG IC 50 value, the lower the cardiotoxicity.

[0133] Experimental materials: experimental compounds (compound 1 prepared by the method of the present application, comparative compound 1), dimethyl sulfoxide (Sigma Aldrich (Shanghai) Trading Co., Ltd.), cisapride (positive control, commercially available), Chinese hamster ovary (CHO) cell line, CHO-hERG cell (Sophion Bioscience Company).

[0134] Manual patch clamp test method:

[0135] CHO-hERG cells in exponential growth phase were collected and resuspended in ECS (extracellular solution) for use. Cells were seeded in recording chamber and placed on an inverted microscope stage. One cell in the recording chamber was randomly selected for testing. The perfusion system was fixed on the inverted microscope stage to continuously perfuse the cells with ECS.

[0136] Glass capillary was used to prepare the hand-made patch clamp recording microelectrode, which was filled with intracellular solution. On the day of patch clamp experiment, the electrode was prepared using borosilicate glass tubing (GC150TF-10, Harvard Apparatus Co. UK). The electrode was filled with ICS and the resistance was between 2-5 MΩ.

[0137] The clamping voltage was -80 mV, the first step depolarization to +60 mV and maintain 850 ms to open hERG channel. Then, the voltage was set to -50 mV and maintained for 1275 ms, generating a rebound current or called tail current, the peak of the tail current will be measured and used for analysis. Finally, the voltage returned to the clamping voltage (-80 mV). At the beginning of the recording stage perfused with solvent control working solution, the peak of the tail current was monitored until stable for more than 3 scan curves, then the test sample / positive control working solution can be perfused until the inhibition of the test sample / positive control working solution on the peak of hERG current reached a steady state.

[0138] hERG current was recorded under whole-cell patch clamp technique, and the recording temperature was room temperature. The patch clamp amplifier output signal was converted to digital through analog-digital conversion and 2.9KHz low-pass filtering, and the data was collected and recorded by Patchmaster Pro software, and Origin8E software was used for data processing and calculation of hERG IC 50 value. The experimental data results are as follows in Table 3:

[0139] Table 3 hERG activity of each compound

[0140] Test Compound Name hERGIC 50 values Compound 1 1.93 μΜ Control Compound 1 0.77 μΜ Cisapride <0.10 μM

[0141] The inhibition of drugs on the hERG potassium ion channel of the heart is the main cause of prolongation of myocardial repolarization, and the half-inhibition concentration (IC 50 ) value of compound 1 on hERG is 1.93 μM. Compared with comparative compound 1, compound 1 of the present application has lower hERG inhibition activity and less toxic side effects on the heart.

[0142] Test Example 3 Metabolic Study

[0143] The metabolic stability of the compound of the example and the rate of generating active substance allopregnanolone were determined by in vitro (human liver microsomal incubation system).

[0144] Experimental materials and reagents: human liver microsomes (Corning Corporation, item number: 452117); testosterone (Jiuding Chemical Co.); propafenone (Anpu Company); diclofenac, tolbutamide, acetonitrile, DMSO from Sigma Company; NADPH (reduced coenzyme II) from Chem-Impex International Company; 0.1M pH7.4 PBS (phosphate buffer, self-prepared); other reagents are analytical pure.

[0145] Instruments, conditions and parameters: liquid chromatography-mass spectrometry (LC / MS / MS, Shimadzu LC 30-AD, MS API4000), the chromatographic column is ACQUITY UPLC BEH C18 column (1.7um 2.1*50mm Column, Part No. 186002350); the mobile phase is acetonitrile-water-formic acid (50:50:0.1); the flow rate is 0.7mL / min; the injection volume is 5μL; the column temperature is room temperature. The electrospray ionization ionization source (ESI) is used, the spray voltage is 4.8KV; the capillary temperature (TEM) is 300℃; the sheath gas N2, the flow rate is 10psi; the auxiliary gas N2, the flow rate is 1psi; the collision gas (CID) Ar, the pressure is 1.5mTorr. The mass spectrometry scanning mode is mass spectrometry multiple reaction monitoring (MRM), and the positive ion mode is detected. The internal standard is 0.2μg / mL tolbutamide in acetonitrile, the minimum quantitative lower limit is 5ng / mL, and the correlation coefficient is >0.99.

[0146] In vitro metabolism research method: taking testosterone, propafenone or diclofenac as a reference to verify the detection system, taking allopregnanolone (compound MI001) and comparative compound 1 as a reference, through the in vitro test of human liver microsomal incubation system, the decrease rate of the concentration of the example compound and the generation rate of MI001 are observed, and the in vitro metabolic stability of each example compound and the ability to maintain the concentration of MI001 in liver microsomes are evaluated.

[0147] Precisely weigh about 10 mg of each sample to be tested, dissolve in 0.1 mL of DMSO, and dilute with pure water to prepare 10 μM and 1 μM standard stock solutions. Perform ice bath operation, and prepare the detection incubation system according to Table 3. Add NADPH to the incubation system (see Table 4 for composition) to start the reaction, immediately take 50 μL in 150 μL of acetonitrile as the zero-time sample and the 1 μM standard curve sample. Take another 1 μM standard stock solution and add it to the incubation system, immediately take 50 μL in 150 μL of acetonitrile as the 0.1 μM standard curve sample. The remaining system is placed in a 37°C water bath, and 50 μL is taken in 150 μL of acetonitrile at 5 min, 15 min, 30 min, 1 h, and 2 h, respectively. Shake each sample and centrifuge at 18000 g for 10 min, and take the supernatant for LC / MS / MS injection determination. The experimental data of some example compounds are shown in Table 5 below.

[0148] Table 4. Composition of the incubation system

[0149] Ingredient Concentration Liver microsomes 0.5 mg protein / mL Test Compound 1 μΜ / 10 μΜ Control Compound 1 μΜ MgCl2 1 mM Acetonitrile 0.99％ DMSO 0.01％ MgCl2 1 mM

[0150] Table 5. Measured concentrations (μM) of the test compounds and MI001 at each time point

[0151]

[0152] The detection system is proved to be normal by the metabolism of testosterone, propafenone or diclofenac; the results of Comparative Compound 1 and the example compounds show that the compounds of the application have good metabolic stability in human liver microsomes; the concentration of allopregnanolone metabolized by the example compounds in the liver microsome system can quickly reach a stable level, while Comparative Compound 1 cannot reach a steady state level.

[0153] Test Example 4: Study on pharmacokinetic properties

[0154] 1. Study on pharmacokinetic properties of SD rats

[0155] The purpose of this experiment is to study the active allopregnanolone in the plasma of SD rats after a single oral administration of each compound solution of the application and allopregnanolone solution, and to evaluate the pharmacokinetic (PK) properties of the compounds in SD rats.

[0156] Experimental materials: male SD rats (body weight 180-220 g, purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd., production license number: SCXK (Jing) 2016-0006), experimental compounds (prepared according to the example method of the application), purified water (self-made).

[0157] Experimental method: Male SD rats were randomly divided into groups (3 rats per group), and free water was provided during the experiment. The rats were fasted for more than 12 hours before administration, and fed 4 hours after administration. The SD rats in each group were orally administered with 5% Tween water solution of the experimental compound at a dose of 20 mg / kg (based on the amount of allopregnanolone).

[0158] Blood samples were collected at 0 min before administration and 5 min, 15 min, 30 min, 1 h, 2 h, 3 h, 4 h, 6 h, 8 h and 12 h after administration into K2EDTA anticoagulant tubes, and stored on ice until centrifugation.

[0159] The blood plasma was centrifuged (8000 rpm, 5 min, 2-8°C) within 60 min after blood collection, and the plasma was transferred to a 96-well plate or a centrifuge tube after centrifugation, transported in an ice box, and stored at ≤-15°C until LC-MS / MS detection. The drug concentration in the plasma of the SD rats was detected by LC-MS / MS biological analysis method, and the blood concentration-time data was analyzed by WinNonlinTM (Version 8.3, Certara, USA) using a non-compartment model to evaluate the pharmacokinetic (PK) characteristics of the drug in the SD rats. The data are shown in Table 6, and the pharmacokinetic curve is shown in Figure 1 .

[0160] Table 6. Pharmacokinetic parameters of allopregnanolone in the plasma of male rats after oral administration of the compound of the present application

[0161]

[0162] Note: "NA" means that it cannot be calculated.

[0163] 2. Pharmacokinetic property study of beagle dogs

[0164] The inventors of the present application found through liver microsomal stability experiments of different species that the metabolism of the compounds of the present application in liver microsomes of different species is basically similar, and the metabolic behavior in beagle dog liver microsomes is closest to that in human liver microsomes. The purpose of this experiment is to study the single oral administration of each compound solution of the present application to beagle dogs, detect the active component allopregnanolone in the plasma, and evaluate the pharmacokinetic (PK) characteristics of the drug in beagle dogs.

[0165] Experimental materials: Male beagle dogs (weight 6-15 kg, purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd.), experimental compounds (prepared according to the method of the present application), and purified water (self-made).

[0166] Experimental method: male beagle dogs were randomly divided into groups (3 dogs per group), free water during the test period, fasting for more than 12 hours before administration, and feeding 4 hours after administration. Oral gavage administration, each group of beagle dogs was given 5% Tween water solution of experimental compound at a dose of 10 mg / kg (based on the amount of allopregnanolone).

[0167] Blood samples were collected at 0 min before administration, 5 min, 15 min, 30 min, 1 h, 2 h, 3 h, 4 h, 6 h, 8 h and 12 h after administration into K2EDTA anticoagulant tubes, and stored on ice until centrifugation.

[0168] Within 30 min after blood collection, blood plasma was centrifuged (at 3200 rpm for 10 min at 2-8℃), and after centrifugation, the plasma was transferred to a 96-well plate or a centrifuge tube, transported in an ice box, and stored at ≤-60℃ for LC-MS / MS detection. The drug concentration in the plasma of beagle dogs was detected by LC-MS / MS biological analysis method, a non-compartment model was used, WinNonlin (Version 6.3 or later version) was used to analyze the blood concentration-time data, and the pharmacokinetic (PK) characteristics in beagle dogs were evaluated, the data are shown in Table 7, and the pharmacokinetic curve is shown in Figure 2 .

[0169] Table 7. Pharmacokinetic parameters of allopregnanolone in the plasma of beagle dogs after oral administration of the compound of the present application

[0170]

[0171] The above results show that the compound of the present application has significantly improved pharmacokinetic properties, in particular, after administration of the compound of the present application, the AUC and Cmax are significantly increased, the compound of the present application can be suitable for oral administration, and can greatly overcome the disadvantages of long administration time and the need for continuous attention of medical personnel of allopregnanolone intravenous preparation, and can greatly improve the compliance of patients and the administration convenience of medical workers.

[0172] The above describes the embodiments of the present application. However, the present application is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A compound of Formula I: ###0001### Formula I or a pharmaceutically acceptable salt thereof. wherein The compound of Formula I is a compound of Formula II: ###0002### Formula II 。 2. A process for the preparation of a compound of claim 1 comprising the steps of: The compound of Formula II is reacted with a compound of Formula III: ###0003### Formula III and the protecting group is removed to obtain the compound of Formula I. wherein R1-R4 are as defined in claim 1 and R5 is a protecting group.

3. The method of claim 2, wherein R5 is Boc.

4. A pharmaceutical composition comprising at least one of the compound of claim 1 or a pharmaceutically acceptable salt thereof.

5. The pharmaceutical composition of claim 4, wherein, The pharmaceutical composition further comprises one or more pharmaceutically acceptable excipients.

6. The pharmaceutical composition of claim 5, wherein, The excipient is a binder, a diluent, a disintegrant, a lubricant, a glidant or a flavoring agent.

7. The pharmaceutical composition of claim 4, wherein, The pharmaceutical composition is for oral administration.

8. The pharmaceutical composition of claim 4, wherein, The pharmaceutical composition is a tablet, a pill, a lozenge, a dragee, a capsule.

9. Use of the compound of claim 1 or a pharmaceutically acceptable salt thereof, or the pharmaceutical composition of any one of claims 4-8, in the manufacture of a medicament for the prevention or treatment of a central nervous system disorder, or for a sedative-hypnotic drug.

10. Use according to claim 9, wherein, The central nervous system disorder is traumatic brain injury, essential tremor, epilepsy, depression and Alzheimer's disease.

11. The use of claim 9, wherein the central nervous system disorder is selected from essential tremor, epilepsy, postpartum or postnatal depression, atypical depression, psychotic major depression, catatonic depression, seasonal affective disorder, dysthymia, double depression, depressive personality disorder, recurrent brief depressive disorder, mild depressive disorder, bipolar disorder or manic-depressive disorder, post-traumatic stress disorder, depression due to a chronic medical condition, treatment-resistant depression, refractory depression.

12. The use of claim 11, wherein the epilepsy comprises refractory status epilepticus, rare genetic epilepsy.

13. The use of claim 12, wherein the rare genetic epilepsy is Dravet syndrome or Rett syndrome.

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