Resolution preparation method of sapropterin hydrochloride

Abstract

The invention belongs to the technical field of medicines, and particularly relates to a resolution preparation method of sapropterin hydrochloride, which comprises the following steps: reacting a sapropterin crude product with a D-type acidic chiral resolution reagent A according to a certain proportion, cooling and crystallizing to obtain R-sapropterin-chiral resolution reagent combined salt; the R-sapropterin-chiral resolution reagent combined salt reacts with an aqueous alkali solution, the chiral resolution reagent is removed, and sapropterin with a high R / S configuration proportion is obtained; and reacting with a concentrated hydrochloric acid aqueous solution to obtain the target product sapropterin hydrochloride. The chiral resolution reagent used in the preparation method is cheap and easy to obtain, and the operation is simple and convenient. The obtained sapropterin product is high in R / S configuration isomerization product content proportion, high in product quality stability and high in quality yield.

Description

Technical Field

[0001] The present invention belongs to the field of pharmaceutical technology, and particularly relates to a method for resolving and preparing sapropterin hydrochloride. Background Art

[0002] Sapropterin, also known as tetrahydrobiopterin ((6R)-BPH4), has the chemical name: (6R)-2-amino-6-[(1R,2S)-1,2-dihydroxypropyl]-5,6,7,8-tetrahydropteridin-4(1H)-one, and its structure is shown as follows:

[0003]

[0004] As a key precursor compound of the specific drug for treating phenylketonuria, sapropterin hydrochloride, (6R)-BPH4 is a cofactor of phenylalanine hydroxylase (PAH). Phenylalanine (Phe) undergoes a hydroxylation reaction under the action of PAH to obtain tyrosine. In PKU patients, the activity of PAH is weak or even non-existent, while (6R)-BPH4 can activate PAH, promote the normal oxidative metabolism of Phe in their bodies, and reduce the Phe level in some patients. Sapropterin hydrochloride is a phenylalanine hydroxylase agonist developed by BioMarin Pharmaceutical Inc., and was first approved by the US FDA for marketing as an orphan drug in December 2007, with the trade name Kuvan. As a specific orphan drug, after the original research product withdrew from the Chinese market, the clinical demand in the domestic market has been increasing year by year.

[0005] Patents WO2013152609A1, WO2005049614A2 and US20060142573 all provide the complete synthetic routes of sapropterin dihydrochloride. The obtained sapropterin (BPH4) is a mixture of 6R and 6S configurational isomers ((6S)-BPH4). Since the polarity difference between the two is small and (6S)-BPH4 is ineffective after entering the human body, complex purification equipment and operations are required to remove impurities, resulting in a sharp increase in production costs and yield losses, which limits the large-scale industrial production application of the process.

[0006] Patent US04713454 provides a route for regulating the amount of (6S)-BPH4 product formed by adjusting the amounts of noble metal catalysts and organic bases used in the catalytic hydrogenation of L-erythro-biopterin to synthesize sapropterin. The specific synthetic route is as follows:

[0007]

[0008] Using L-erythro-biopterin as the starting material, adjusting the pH to 12 with triethylamine, converting it to sapropterin under a hydrogen pressure of 10 Mpa and platinum black catalysis, and then reacting with a concentrated hydrochloric acid-ethanol solution to form sapropterin hydrochloride. In the actual application process, it is found that the hydrogenation pressure is too high, which belongs to a high-risk reaction. Moreover, the triethylamine used in the reaction easily combines with hydrochloric acid to form triethylamine hydrochloride, which is likely to remain in the relatively polar sapropterin, resulting in difficulty in ensuring the quality of the final product.

[0009] Patent CN102443006B provides a preparation method for selectively producing (6R)-tetrahydrobiopterin hydrochloride by hydrogenating L-biopterin in a basic matrix containing a solvent, potassium hydroxide, and potassium dihydrogen phosphate in the presence of a platinum-based metal catalyst. The synthetic route is as follows:

[0010]

[0011] This method also has problems such as a long hydrogenation reaction time, multiple crystallization, cumbersome operation, a low ratio of R / S configuration products in the obtained product (4.1 - 4.5:1), and a low yield of pure product (29 - 32%). This process has a high economic cost, and crystal seeds need to be introduced during the crystallization process, so there are significant problems in its application.

[0012] Therefore, in the above-mentioned sapropterin preparation methods, there are problems such as a low yield of (6R)-BPH4, a large amount of (6S)-BPH4 impurities, a low content of active ingredients, or high technical requirements, high risk of explosion, and high production costs, which are not conducive to large-scale industrial production. Summary of the Invention

[0013] In view of the deficiencies of the prior art, the present invention provides a resolution preparation method for sapropterin hydrochloride. The chiral resolution reagent used in the preparation method of the present invention is cheap and easily available, and the operation is simple. The obtained sapropterin product has a high content ratio of R / S configuration isomers, high product quality stability, and high mass yield.

[0014] The present invention is specifically realized through the following technical solutions:

[0015] A resolution preparation method for sapropterin hydrochloride, comprising the following steps: (1) reacting a crude sapropterin product with a D-type acidic chiral resolution reagent A in a certain ratio, and performing crystallization by cooling to obtain an R-sapropterin-chiral resolution reagent binding salt;

[0016] (2) reacting the R-sapropterin-chiral resolution reagent binding salt with an aqueous alkali solution to remove the chiral resolution reagent and obtain sapropterin with a high R / S configuration ratio;

[0017] (3) reacting the product of the above step (2) with an aqueous concentrated hydrochloric acid solution to obtain the target product sapropterin hydrochloride.

[0018] The above steps are described in detail in the following sections:

[0019] Step (1): In solvent B, the crude sapropterin is fed with the D-type acidic chiral resolution reagent A in molar equivalents, and the reaction is carried out under temperature control. After detecting that the reaction is complete, the reaction system is cooled, stirred for crystallization, and centrifuged (or suction filtered) to obtain the R-sapropterin-chiral resolution reagent binding salt, which is directly used for the next reaction step.

[0020] Preferred embodiment, the D-type acidic chiral resolution reagent A described in step (1) is selected from one or more of D-tyrosine, D-aspartic acid, D-pyroglutamic acid, and D-(+)-camphoric acid; more preferably D-aspartic acid.

[0021] Preferred embodiment, the dosage of the D-type acidic chiral resolution reagent A in step (1) is as follows: for D-aspartic acid and D-(+)-camphoric acid, the molar ratio of sapropterin to D-type acidic chiral resolution reagent A = 1:2.4 - 3; preferably 1:2.5; for D-tyrosine and D-pyroglutamic acid, the molar ratio of sapropterin to D-type acidic chiral resolution reagent A = 1:5 - 6; preferably 1:5.

[0022] Preferred embodiment, the temperature-controlled reaction temperature in step (1) is 45 - 55 °C.

[0023] Preferred embodiment, the temperature reduction in step (1) is 15 - 25 °C.

[0024] Step (2): Dissolve the R-sapropterin-chiral resolution reagent binding salt prepared in the above step in solvent B. After complete dissolution, add an aqueous solution of base C, carry out the reaction under temperature control, continue the reaction after cooling, remove the protection of the D-type acidic chiral resolution reagent. After detecting that the reaction is complete, centrifuge (or suction filter) to obtain sapropterin with a high R / S configuration ratio.

[0025] Preferred embodiment, the base C described in step (2) is selected from one of sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water, and sodium bicarbonate; more preferably sodium hydroxide.

[0026] Preferred embodiment, the mass fraction of the aqueous solution of base C in step (2) is 5% - 15%, preferably 10%.

[0027] Preferred embodiment, the temperature control in step (2) is 55 - 65 °C.

[0028] Preferred embodiment, the temperature reduction in step (2) is 20 - 30 °C.

[0029] Preferred embodiment: In steps (1) and (2), the solvent B is selected from one or more of water, methanol, ethanol, isopropanol, 50% aqueous methanol solution, 75% aqueous ethanol solution, and 95% aqueous ethanol solution; more preferably, it is 95% aqueous ethanol solution.

[0030] Step (3): Preparation of sapropterin hydrochloride

[0031] Completely dissolve sapropterin with a high R / S configuration ratio in hydrochloric acid aqueous solution to form a salt, and after recrystallization with absolute ethanol at 0 - 5 °C and centrifuging (or suction filtration), obtain the sapropterin hydrochloride product.

[0032] Preferred embodiment: The concentration of the hydrochloric acid aqueous solution in step (3) is 6 - 8 mol / L.

[0033] The above steps are further described in detail in the following parts:

[0034] Step (1): Add to the three-necked glass reaction flask the solvent B, and charge sapropterin and the D-type acidic chiral resolution reagent A according to the molar equivalent, and react at 45 - 55 °C for 1 - 2 hours. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. After the reaction is completed, cool the reaction system to 15 - 25 °C, stir and react for 4 - 6 hours, then centrifuge (or suction filter). Wash the filter cake with an appropriate amount of the solvent B twice, and then dry it under vacuum at no higher than 35 °C for 24 h to obtain the R-sapropterin-chiral resolution reagent binding salt, which is directly used for the next step of the reaction.

[0035] The dosage of the organic solvent B in step (1) is: calculated by weight g / volume mL (hereinafter represented by (W / V, g / mL)), sapropterin: solvent B = 1:5 - 10 g / mL, preferably 1:8 g / mL; the solvent B is one or more of water, methanol, ethanol, isopropanol, 50% aqueous methanol solution, 75% aqueous ethanol solution, and 95% aqueous ethanol solution; more preferably, it is 95% aqueous ethanol solution.

[0036] The dosage of the D-type acidic chiral resolution reagent A in step (1) is: for D-aspartic acid and D-(+)-camphoric acid, the molar ratio of sapropterin: D-type acidic chiral resolution reagent A = 1:2.4 - 3; preferably 1:2.5; for D-tyrosine and D-pyroglutamic acid, the molar ratio of sapropterin: D-type acidic chiral resolution reagent A = 1:5 - 6; preferably 1:5.

[0037] Step (2): Add solvent B into a three-necked glass reaction flask. Start stirring, control the temperature at 30 - 40°C, and slowly add the R-sapropterin-chiral resolution reagent binding salt prepared in step (1). After stirring until completely dissolved, add a certain amount of 10% aqueous solution of base C dropwise to the reaction solution within 30 min. After stirring for 10 min, raise the temperature to 55 - 65°C and react for 2 - 4 h, then cool down to 20 - 30°C and continue to keep the temperature for reaction for 6 - 8 h to remove the D-type acidic chiral resolution reagent protection. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. Centrifuge (or filter) to remove the chiral resolution reagent, and obtain sapropterin with a high R / S configuration ratio. Wash the filter cake with an appropriate amount of solvent B twice, and then place it in a vacuum dryer at no higher than 35°C for 24 h to obtain sapropterin with a high R / S configuration ratio.

[0038] The dosage of the organic solvent B when dissolving in step (2) is: R-sapropterin-chiral resolution reagent binding salt: solvent B = 1: 3 - 5 g / mL, preferably 1: 4 g / mL; the solvent B is one or more of water, methanol, ethanol, isopropanol, 50% aqueous methanol solution, 75% aqueous ethanol solution, 95% aqueous ethanol solution; further preferably 95% aqueous ethanol solution.

[0039] The base C in step (2) is selected from one of sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water and sodium bicarbonate; further preferably sodium hydroxide; the dosage mass ratio of the 10% aqueous solution of base C is R-sapropterin-chiral resolution reagent binding salt: 10% aqueous solution of base C = 1: 1.7 - 1.9, preferably 1: 1.8 (W / W).

[0040] Step 3: Preparation of sapropterin hydrochloride

[0041] Add 6 mol / L hydrochloric acid aqueous solution with the feeding amount into a three-necked glass reaction flask. Start stirring, control the temperature at 20 - 30°C, slowly add sapropterin with a high R / S configuration ratio. After stirring until completely dissolved, add a certain amount of absolute ethanol dropwise into the reaction system within 60 min, then cool down to 0 - 5°C for recrystallization for 14 - 16 h. Centrifuge (or filter) to remove the solvent, and obtain sapropterin hydrochloride. Wash the filter cake with an appropriate amount of absolute ethanol twice, and then place it in a vacuum dryer at no higher than 35°C to obtain sapropterin hydrochloride.

[0042] The dosage of the 6 mol / L hydrochloric acid aqueous solution is selected as sapropterin with a high R / S configuration ratio: 6 mol / L hydrochloric acid aqueous solution = 1: 6 (W / V, g / mL).

[0043] The dosage of the absolute ethanol used in the recrystallization step is sapropterin with a high R / S configuration ratio: absolute ethanol = 1: 20 (W / V, g / mL).

[0044] Advantages of the present invention:

[0045] All kinds of reagents used are cheap and easily available, and there are relatively mature treatment methods for the generated pollutants, resulting in little environmental pollution. The overall method is simple and easy to operate, with undemanding technical requirements for practitioners. At the same time, each reaction step has a stable reaction and is easy to control, with a high R / S ratio, few impurities, stable quality, and high yield of the generated sapropterin.

[0046] The present invention solves the problem that the R / S ratio in the sapropterin obtained by the prior art is too low, resulting in the over-standard of the S configuration impurities with similar polarities in the final product of sapropterin hydrochloride, and further separation and purification are required by means of complex purification instruments and equipment. The overall process is time-consuming, consumes a large amount of energy, requires a large investment in equipment, and has high skill requirements for practitioners.

[0047] In summary, the present invention is efficient, economical, and simple in production operation, fully meeting the requirements of industrial mass production. Description of the drawings

[0048] Figure 1 It is the HPLC chromatogram of sapropterin hydrochloride (R / S = 49.4:1); the relative retention time of sapropterin hydrochloride is 36.758 minutes.

[0049] Figure 2 It is the MS chromatogram of sapropterin hydrochloride.

[0050] Figure 3 It is for sapropterin hydrochloride 1 1H-NMR spectrum.

[0051] Figure 4 It is for sapropterin hydrochloride 13 13C-NMR spectrum. Detailed implementation manners

[0052] The present invention will be further described below through examples. It should be correctly understood that the examples of the present invention are only used to illustrate the present invention, rather than limiting the present invention. Therefore, simple improvements to the present invention under the premise of the method of the present invention fall within the scope claimed by the present invention.

[0053] Example 1

[0054] Step (1):

[0055] Add an aqueous solution of 95% ethanol with a ratio of 1:8 (safinamide: solvent B; W / V, g / mL) to a three-necked glass reaction flask. Charge 1 g of safinamide (R / S = 5:1) and chiral acid resolution reagent A in a molar equivalent ratio of 1:2.5, and react at 45 - 55 °C for 1 hour. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. After the reaction is completed, cool the reaction system to 15 - 25 °C, stir and react for 4 hours, and then centrifuge (or filter) to obtain a filter cake. Wash the filter cake twice with an aqueous solution of 95% ethanol with a ratio of 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 hours to obtain the R-safinamide-chiral resolution reagent binding salt, which is directly used for the next reaction.

[0056] Step (2):

[0057] Add an aqueous solution of 95% ethanol with a ratio of 1:4 (R-safinamide-chiral resolution reagent binding salt: solvent B; W / V, g / mL) to a three-necked glass reaction flask. Start stirring and control the temperature at 30 - 40 °C. Slowly add the R-safinamide-chiral resolution reagent binding salt prepared in step (1). After stirring until completely dissolved, add a 10% aqueous sodium hydroxide solution with a ratio of 1:1.8 (R-safinamide-chiral resolution reagent binding salt: solution of base C; W / W) equivalent to the reaction solution dropwise within 30 minutes. After stirring for 10 minutes, raise the temperature to 55 - 65 °C and react for 2 hours, then cool to 20 - 30 °C and continue to hold the temperature and react for 6 hours. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. Centrifuge (or filter) to obtain a filter cake. Wash the filter cake twice with an aqueous solution of 95% ethanol with a ratio of 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 hours to obtain safinamide with a high R / S configuration ratio. Determine the ratio of R / S configuration products according to the following chromatographic conditions: Chromatographic column: Waters Spherisorb SCX column (inert silica gel bonded with sulfonic acid group cations as the packing material, 4.6 mm × 250 mm, 5 μm); Mobile phase: 50 mmol / L potassium dihydrogen phosphate solution - acetonitrile (80:20), isocratic elution; Detection wavelength: 220 nm; Flow rate: 1.0 mL / min; Column temperature: 30 °C; Sample chamber temperature: 4 °C; Injection volume: 20 μL.

[0058] Step (3):

[0059] Add 6 mol / L hydrochloric acid aqueous solution in an amount 1:6 (safinamide with a high R / S configuration ratio: hydrochloric acid solution; W / V, g / mL) times that of the safinamide with a high R / S configuration ratio prepared in step (2) to a three-necked glass reaction flask. Start stirring, control the temperature at 20 - 30 °C, slowly add the safinamide with a high R / S configuration ratio prepared in step (2), and after stirring until completely dissolved, add anhydrous ethanol in an amount 20 times that of the safinamide with a high R / S configuration ratio (safinamide with a high R / S configuration ratio: anhydrous ethanol = 1:20; W / V, g / mL) dropwise to the reaction system within 60 min. Then cool down to 0 - 5 °C and recrystallize for 16 h. Centrifuge (or filter by suction) to remove the solvent to obtain a safinamide hydrochloride filter cake. Wash the filter cake twice with 95% ethanol aqueous solution in a ratio of 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then place it in a vacuum dryer at no higher than 35 °C for 24 h to obtain safinamide hydrochloride.

[0060] White crystals. Elemental analysis results: Calculated for C9H 17 Cl2N5O3: C, 34.41; H, 5.45; N, 22.29. Found C, 34.48; H, 5.44; N, 22.37. Specific rotation -6.39° (c 0.68, 0.1 mol / L HCl(aq)). MS ESI + : m / z: 242.12 [M + H] + ; 264.11 [M + Na] + ; 1 1H NMR (400 MHz, D2O) δ 3.74 - 3.63 (m, 4H), 3.46 (dd, J = 9.5 Hz, 1H), 1.16 (d, J = 5.5 Hz, 3H); 13 13C NMR (100 MHz, DMSO-d6) δ 156.74, 153.57, 151.98, 85.80, 71.69, 68.73, 54.43, 37.89, 21.51.

[0061] In step (1), a mono-carboxylic acid D-type acid is selected, and the test results of the final product safinamide hydrochloride are shown in the following table:

[0062] Table 1 Experimental results of mono-carboxylic acid D-configuration acid

[0063]

[0064]

[0065] Example 2

[0066] Step (1):

[0067] Add an aqueous solution of 95% ethanol with a ratio of 1:8 (safinamide: solvent B; w / v, g / mL) to a three-necked glass reaction flask. Charge 1 g of safinamide (R / S = 5:1) and chiral acid resolving agent A in a molar equivalent ratio of 1:5, and react at 45 - 55 °C for 1 hour. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the starting materials should basically disappear. After the reaction is complete, cool the reaction system to 15 - 25 °C, stir and react for 4 hours, and obtain the filter cake by centrifugation (or suction filtration). Wash the filter cake twice with an aqueous solution of 95% ethanol with a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 h to obtain the R-safinamide-chiral resolving agent complex salt, which is directly used for the next reaction.

[0068] Step (2):

[0069] Add an aqueous solution of 95% ethanol with a ratio of 1:4 (R-safinamide-chiral resolving agent complex salt: solvent B; w / v, g / mL) to a three-necked glass reaction flask. Start stirring and control the temperature at 30 - 40 °C. Slowly add the R-safinamide-chiral resolving agent complex salt prepared in step (1). After stirring until completely dissolved, add a 10% aqueous sodium hydroxide solution with a ratio of 1:1.8 (R-safinamide-chiral resolving agent complex salt: solution of base C; w / w) equivalent to the reaction solution dropwise within 30 min. After stirring for 10 min, raise the temperature to 55 - 65 °C and react for 2 h, then cool to 20 - 30 °C and continue to keep the temperature for reaction for 6 h. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the starting materials should basically disappear. Obtain the filter cake by centrifugation (or suction filtration). Wash the filter cake twice with an aqueous solution of 95% ethanol with a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 h to obtain safinamide with a high R / S configuration ratio. Determine the ratio of the R / S configuration products according to the chromatographic conditions described in Example 1.

[0070] Step (3):

[0071] Add 6 mol / L hydrochloric acid aqueous solution in an amount 1:6 (safinamide with a high R / S configuration ratio: hydrochloric acid solution; W / V, g / mL) times that of the safinamide with a high R / S configuration ratio prepared in step (2) to a three-necked glass reaction flask. Start stirring, control the temperature at 20 - 30°C, slowly add the safinamide with a high R / S configuration ratio prepared in step (2), and after stirring until completely dissolved, add 20 times the amount (safinamide with a high R / S configuration ratio: absolute ethanol = 1:20; W / V, g / mL) of absolute ethanol dropwise to the reaction system within 60 min, then cool down to 0 - 5°C for recrystallization for 16 h, and remove the solvent by centrifugal discharging (or suction filtration) to obtain a safinamide hydrochloride filter cake. Wash the filter cake twice with 95% ethanol aqueous solution in an amount 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then dry it under vacuum at no higher than 35°C for 24 h to obtain safinamide hydrochloride.

[0072] In step (1), a double-acid-based D-type acid is selected, and the test results of the final product safinamide hydrochloride are shown in the following table:

[0073] Table 2 Experimental results of dicarboxyl D-configuration acid

[0074]

[0075] Example 3

[0076] Step (1):

[0077] Add to a three-necked glass reaction flask 1 g of safinamide (R / S = 5:1) and the chiral resolution reagent D-aspartic acid in a molar equivalent ratio of 1:2.5 to solvent B in an amount 1:8 (safinamide: solvent B; W / V, g / mL), and react at 45 - 55°C for 1 h. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. After the reaction is completed, cool the reaction system to 15 - 25°C, stir and react for 4 h, and then perform centrifugal discharging (or suction filtration) to obtain a filter cake. Wash the filter cake twice with the solvent in an amount 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then dry it under vacuum at no higher than 35°C within 24 h to obtain the R-safinamide-chiral resolution reagent binding salt, which is directly used for the next step of the reaction.

[0078] Step (2):

[0079] Add solvent B with a ratio of 1:4 (R-sapropterin-chiral resolution reagent binding salt: solvent B; w / v, g / mL) to a three-necked glass reaction flask. Start stirring, control the temperature at 30-40 °C, and slowly add the R-sapropterin-chiral resolution reagent binding salt prepared in step (1). After stirring until completely dissolved, add a 10% aqueous sodium hydroxide solution equivalent to 1:1.8 (R-sapropterin-chiral resolution reagent binding salt: alkali C solution; w / w) dropwise to the reaction solution within 30 min. After stirring for 10 min, raise the temperature to 55-65 °C and react for 2 h, then cool down to 20-30 °C and continue to react while maintaining the temperature for 6 h. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the raw materials should basically disappear. Centrifuge (or filter) to obtain a filter cake. Wash the filter cake twice with solvent B at a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then place it in a vacuum dryer at no higher than 35 °C for 24 h to obtain sapropterin with a high R / S configuration ratio. Determine the ratio of the R / S configuration products according to the chromatographic conditions described in Example 1.

[0080] Step (3):

[0081] Add a 6 mol / L hydrochloric acid aqueous solution in an amount 1:6 (sapropterin with a high R / S configuration ratio: hydrochloric acid solution; w / v, g / mL) times to a three-necked glass reaction flask. Start stirring, control the temperature at 20-30 °C, and slowly add the sapropterin with a high R / S configuration ratio prepared in step (2). After stirring until completely dissolved, add absolute ethanol in an amount 20 times (sapropterin with a high R / S configuration ratio: absolute ethanol = 1:20; w / v, g / mL) to the reaction system within 60 min, then cool down to 0-5 °C for recrystallization for 16 h, and centrifuge (or filter) to remove the solvent to obtain a filter cake of sapropterin hydrochloride. Wash the filter cake twice with a 95% ethanol aqueous solution at a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then place it in a vacuum dryer at no higher than 35 °C for 24 h to obtain sapropterin hydrochloride.

[0082] The test results of the final product sapropterin hydrochloride prepared by selecting different solvent Bs in step (1) are shown in the following table:

[0083] Table 3 Experimental results of different solvent Bs

[0084]

[0085] Example 4

[0086] Step (1):

[0087] Add a 95% ethanol aqueous solution with a ratio of 1:8 (safinamide: solvent B; w / v, g / mL) to a three-necked glass reaction flask. Charge 1 g of safinamide (R / S = 5:1) and the chiral resolution reagent D-aspartic acid in a molar equivalent ratio of 1:2.5, and react at 45 - 55 °C for 1 hour. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the starting materials should basically disappear. After the reaction is completed, cool the reaction system to 15 - 25 °C, stir and react for 4 hours, and centrifuge (or filter) to obtain a filter cake. Wash the filter cake twice with a 95% ethanol aqueous solution with a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 h to obtain the R-safinamide-chiral resolution reagent binding salt, which is directly used for the next reaction.

[0088] Step (2):

[0089] Add a 95% ethanol aqueous solution with a ratio of 1:4 (R-safinamide-chiral resolution reagent binding salt: solvent B; w / v, g / mL) to a three-necked glass reaction flask. Start stirring and control the temperature at 30 - 40 °C. Slowly add the R-safinamide-chiral resolution reagent binding salt prepared in step (1). After stirring until completely dissolved, add a 10% aqueous solution of base C with a ratio of 1:1.8 (R-safinamide-chiral resolution reagent binding salt: base C solution; w / w) equivalent dropwise to the reaction solution within 30 min. After stirring for 10 min, raise the temperature to 55 - 65 °C and react for 2 h, then cool to 20 - 30 °C and continue to keep warm and react for 6 h. TLC detection: Using n-butanol / acetic acid / water (volume ratio 4 / 1 / 5) as the developing agent, the spots of the starting materials should basically disappear. Centrifuge (or filter) to obtain a filter cake. Wash the filter cake twice with a 95% ethanol aqueous solution with a ratio of 1:1.5 (filter cake: washing solvent; w / v, g / mL), and then dry it under vacuum at no higher than 35 °C for 24 h to obtain safinamide with a high R / S configuration ratio. Determine the ratio of the R / S configuration products according to the chromatographic conditions described in Example 1.

[0090] Step (3):

[0091] Add 6 mol / L hydrochloric acid aqueous solution in an amount 1:6 (Sapropterin with a high R / S configuration ratio: hydrochloric acid solution; W / V, g / mL) times that of sapropterin with a high R / S configuration ratio prepared in step (2) to a three-necked glass reaction flask. Start stirring, control the temperature at 20 - 30 °C, slowly add the sapropterin with a high R / S configuration ratio prepared in step (2), and after stirring until completely dissolved, add anhydrous ethanol in an amount 20 times that of the sapropterin with a high R / S configuration ratio (sapropterin with a high R / S configuration ratio: anhydrous ethanol = 1:20; W / V, g / mL) dropwise to the reaction system within 60 min, then cool down to 0 - 5 °C for recrystallization for 16 h, and centrifuge (or filter by suction) to remove the solvent to obtain a filter cake of sapropterin hydrochloride. Wash the filter cake twice with 95% ethanol aqueous solution in a ratio of 1:1.5 (filter cake: washing solvent; W / V, g / mL), and then place it in a vacuum dryer at no higher than 35 °C for 24 h to obtain sapropterin hydrochloride.

[0092] In step (2), different bases C were selected, and the test results of the final product sapropterin hydrochloride are shown in the following table:

[0093] Table 4 Influence of different bases on experimental results

[0094]

[0095] Comparative Example 1

[0096] In a three-necked glass reaction flask, add 0.05 g of platinum dioxide to 50 mL of water, add 0.5 g of L-biopterin under stirring, adjust the pH value to 11.5 with potassium hydroxide and potassium dihydrogen phosphate, transfer the mixture to an autoclave, fill it with hydrogen at 4.0 MPa, react at 14 °C for 50 hours, then filter off the catalyst, add concentrated hydrochloric acid to adjust the pH = 1.0, and then distill off water under reduced pressure. The obtained solid was determined by HPLC as described in Example 1 for its R / S isomer ratio, which was 4.2:1. Add 20 mL of ethanol to dissolve the product, filter off the insoluble inorganic salts, remove the solvent from the filtrate under reduced pressure, add 2.5 mL of 3 mol / L hydrochloric acid aqueous solution to dissolve it, add 5 mL of anhydrous ethanol dropwise, add seed crystals, and place it at 0 °C to precipitate crystals. Filter by suction, add 1.5 mL of mol / L hydrochloric acid aqueous solution to dissolve the obtained white solid, slowly add 1.5 mL of anhydrous ethanol to the solution, and then place it at 0 °C for 6 h to slowly precipitate crystals. Filter by suction and dry to obtain white crystals of sapropterin hydrochloride with a purity of 99.5% and a yield of 36.4%.

[0097] Comparative Example 2

[0098] Add 92 mL of purified water, 1.0 g of L-biopterin and 0.20 g of platinum black into a three-necked glass reaction flask. Then add 10% aqueous triethylamine solution to adjust the pH of the reaction solution to 12.0. Place the reaction solution in a high-pressure reactor, continuously shake it at a speed of 1000 rpm, introduce H2 and maintain the pressure at 10 MPa, and react at 0 - 5 °C for 20 h. After the reaction is completed, add 5 mL of concentrated hydrochloric acid to the reaction solution and filter to remove the catalyst. Concentrate the filtrate to dryness at no higher than 35 °C. Determine the R / S isomer ratio by the HPLC method described in Example 1, which is 21:1. The product is recrystallized from a mixed solvent of 3 mol / L hydrochloric acid aqueous solution and ethanol to obtain white crystals of sapropterin hydrochloride, with a purity of 99.2% and a yield of 81.2%.

Claims

1. A method for the resolution and preparation of sapropterin hydrochloride, characterized in that, It includes the following steps: (1) reacting the crude sapropterin with the D-type acidic chiral resolution reagent A in a certain ratio, cooling and crystallizing to obtain the R-sapropterin-chiral resolution reagent binding salt; (2) reacting the R-sapropterin-chiral resolution reagent binding salt with an aqueous alkali solution to remove the chiral resolution reagent and obtain sapropterin with a high ratio of R / S configurations; (3) reacting the product of the above step (2) with an aqueous hydrochloric acid solution to obtain the target product sapropterin hydrochloride.

2. The method according to claim 1, wherein Step (1): In solvent B, charge the crude sapropterin and the D-type acidic chiral resolution reagent A according to molar equivalents, control the temperature for reaction. After detecting that the reaction is complete, cool the reaction system, stir and crystallize, and centrifuge (or filter) to obtain the R-sapropterin-chiral resolution reagent binding salt, which is directly used for the next step of reaction; Step (2): Dissolve the R-sapropterin-chiral resolution reagent binding salt prepared in the above step in solvent B. After complete dissolution, add an aqueous solution of alkali C, control the temperature for reaction, continue the reaction after cooling, remove the protection of the D-type acidic chiral resolution reagent. After detecting that the reaction is complete, centrifuge (or filter) to obtain sapropterin with a high ratio of R / S configurations; Step (3): Preparation of sapropterin hydrochloride Completely dissolve the sapropterin with a high ratio of R / S configurations in an aqueous hydrochloric acid solution to form a salt. After recrystallization with absolute ethanol at 0 - 5 °C and centrifuging (or filtering), obtain the sapropterin hydrochloride product.

3. The method according to claim 2, wherein The D-type acidic chiral resolution reagent A described in step (1) is selected from one or more of D-tyrosine, D-aspartic acid, D-pyroglutamic acid, D-(+)-camphoric acid; further preferably D-aspartic acid.

4. The method according to claim 2, wherein The dosage of the D-type acidic chiral resolution reagent A in step (1) is as follows: the molar ratio of the dosage of D-aspartic acid and D-(+)-camphoric acid is sapropterin:D-type acidic chiral resolution reagent A = 1:2.4 - 3; preferably 1:2.5; the molar ratio of the dosage of D-tyrosine and D-pyroglutamic acid is sapropterin:D-type acidic chiral resolution reagent A = 1:5 - 6; preferably 1:

5.

5. The method according to claim 2, wherein The temperature for the temperature-controlled reaction in step (1) is 45 - 55 °C.

6. The method according to claim 2, wherein The temperature for cooling in step (1) is 15 - 25 °C.

7. The method according to claim 2, wherein The alkali C described in step (2) is selected from one of sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water, and sodium bicarbonate; further preferably sodium hydroxide.

8. The method according to claim 2, wherein The temperature control in step (2) is 55 - 65 °C.

9. The method according to claim 2, wherein The temperature for cooling in step (2) is 20 - 30 °C.

10. The method according to claim 2, characterized in that The solvent B described in steps (1) and (2) is selected from one or more of water, methanol, ethanol, isopropanol, 50% aqueous methanol solution, 75% aqueous ethanol solution, 95% aqueous ethanol solution; Further preferably 95% aqueous ethanol solution.

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