Monocrystal of andrographolide acid trihydrate and preparation method thereof
By developing a method for preparing single crystals of andrographolide trihydrate, the problem of high-purity preparation was solved, the bioavailability and dissolution of the drug were improved, and the large-scale production of high-purity crystals and efficient drug dissolution were realized.
Patent Information
- Application Number
- CN202211648424.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-12-21
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2042-12-21
AI Technical Summary
Existing technologies have failed to effectively prepare high-purity single crystals of andrographolide trihydrate, and their bioavailability and drug dissolution are low.
Andrographolide and potassium hydroxide were reacted in an ethanol-water solution in a specific ratio. Then, the solvent was recovered under reduced pressure, the pH was adjusted, the precipitate was filtered, the precipitate was eluted with an acetonitrile-water gradient, and the product was dried under vacuum to prepare single crystals of andrographolide trihydrate.
The obtained andrographolide trihydrate single crystals have good crystallinity, significantly improved drug dissolution, and HPLC content of over 99%. The preparation method is simple, environmentally friendly, and can be scaled up.
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Figure CN115819225B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a monocrystal of andrographolide acid trihydrate, a preparation method and application thereof, and belongs to the field of drug crystal form research. BACKGROUND
[0002] Andrographolide is the main active ingredient of Andrographis Herba, which can be used for treating pharyngolaryngitis, pneumonia, influenza, enteritis and dysentery. Andrographolide is difficult to dissolve in water and has low bioavailability. Modifying the structure of andrographolide can help to increase bioavailability and improve activity. Andrographolide acid is a hydrolysis product of andrographolide, and has significant anti-inflammatory and immunosuppressive effects, and is a potential pharmaceutical raw material.
[0003] Han G, Zeng C, Du GJ, et al. Synthesis of andrographolide derivatives and their anti-inflammatory and immunomodulatory activities [J]. Chinese Traditional and Herbal Drugs, 2006, 37(12): 1771-1775, reported a synthesis technology of andrographolide acid. The inventors added andrographolide 5 g, which was ground into fine powder, into a 250 mL single-necked flask, and then added potassium hydroxide aqueous solution (10 g of potassium hydroxide was dissolved in 25 mL of water) and 50 mL of ethanol in sequence. The solution was heated to reflux for 2 h, cooled to room temperature, and filtered. No filter cake appeared after the solution was filtered. The experimental phenomenon was inconsistent with the description in the existing published technology. It can be seen that high-purity andrographolide acid cannot be synthesized according to the above published technology.
[0004] At present, there is no report on a monocrystal of andrographolide acid trihydrate and a preparation method thereof. SUMMARY
[0005] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide a monocrystal of andrographolide acid trihydrate.
[0006] The second purpose of the present application is to provide a preparation method of the monocrystal of andrographolide acid trihydrate.
[0007] The technical solution of the present application is summarized as follows:
[0008] A monocrystal of andrographolide acid trihydrate, the chemical formula of which is C 20 H 32 O6.3(H2O), the formula weight of which is 422.50, the crystal structure of which is orthorhombic, and the space group of which is α=90°, β=90°, γ=90°, Z=4; the chemical structural formula is shown in formula (I):
[0009]
[0010] A preparation method of a monocrystal of andrographolide acid trihydrate, comprising the following steps:
[0011] Andrographolide and potassium hydroxide are put in an 80%-90% ethanol aqueous solution with a volume concentration corresponding to 12 times the mass of andrographolide in a proportion of 1:1, and reacted. The solvent is recovered to dryness under reduced pressure, and water corresponding to 10 times the mass of andrographolide is added to dissolve it. The filtrate is adjusted to a pH of 6-7 with dilute hydrochloric acid, and left to stand for 30 minutes. A precipitate is separated out, and suction filtration is performed. The filter cake is dissolved in a 90%-99.5% ethanol aqueous solution with a volume concentration corresponding to 10 times the mass of andrographolide, and separated by chromatography on a column of octadecylsilane-bonded silica gel. Elution is performed by gradient elution with 0 min 20% acetonitrile in water, increasing to 35% acetonitrile in water at a rate of 1.5% per minute over 10 min, and collecting the eluate at 30%-35% acetonitrile in water. The solvent is evaporated, and the crystals are separated out, filtered, and dried under vacuum at room temperature to obtain andrographolide acid trihydrate single crystals.
[0012] Advantages of the present application
[0013] The andrographolide acid trihydrate single crystals obtained by the present application have good crystallinity, and the content calculated by the HPLC peak area normalization method can reach more than 99%. The dissolution rate of the andrographolide acid trihydrate single crystals obtained by the present application is significantly higher than that of andrographolide acid powder prepared by the prior art. The preparation method used by the present application is simple to operate, safe, environmentally friendly, and can be applied on a large scale. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 Figure 1 is an X-ray single crystal diffraction pattern of andrographolide acid trihydrate single crystals of the present application;
[0015] Figure 2 Figure 2 is an HPLC pattern of andrographolide acid trihydrate single crystals of the present application;
[0016] Figure 3 Figure 3 is a crystal cell packing pattern of andrographolide acid trihydrate single crystals of the present application. DETAILED DESCRIPTION
[0017] The present application will be further described below through specific examples.
[0018] The structure and performance of the instruments used for preparation and detection in the present application are as follows:
[0019] X-ray single crystal diffraction analysis was performed using a Japan Rigaku Xtalab P200 single crystal diffractometer with a Cu-Kα target, and data was collected at 294 K.
[0020] Preparation of liquid chromatography conditions, the chromatographic column is Agilent ZORBAX SB-C18 7μm 21.2*250mm, mobile phase A is pure water, mobile phase B is acetonitrile, flow rate is 20mL / min gradient elution, 0min~10min, 20%B~35%B, detection wavelength is 190nm~400nm.
[0021] High pressure liquid chromatography (HPLC) determination conditions, the chromatographic column is HSS T3 1.8μm 2.1×100mm, mobile phase A is 0.1%phosphoric acid aqueous solution, mobile phase B is acetonitrile, 0.4mL / min flow rate linear gradient elution: 0min~1min, 20%B; 1min~6min, 20%B~70%B, column temperature 30℃, detection wavelength 225nm.
[0022] Example 1
[0023] A preparation method of andrographolide acid trihydrate single crystal, comprising the following steps:
[0024] Andrographolide 5.0g (14mmol), potassium hydroxide 0.81g (14mmol), add 60g volume concentration of 83%ethanol aqueous solution (also can be selected 80%ethanol aqueous solution or 90%ethanol aqueous solution), 60℃ reaction 1 hour, the solution is complete clarification, recovery of solvent to dryness under reduced pressure, add 50g water to dissolve, filter, the filtrate is added to mass concentration of 10%dilute hydrochloric acid, adjust pH to 6.5 (also can be adjusted to pH = 6 or pH = 7), stand for 30 minutes, precipitate, suction filtration, filter cake is added to 50g volume concentration of 90%ethanol aqueous solution (also can be selected 99.5%ethanol aqueous solution) to dissolve, with octadecylsilane bonded silica gel chromatography preparation column separation, with 0min volume concentration of 20%acetonitrile in water is increased to 35%acetonitrile in water at 10min gradient elution, collection of 30%-35%acetonitrile in water eluent, evaporation of solvent, crystallization, filtration, vacuum drying at room temperature, andrographolide acid trihydrate single crystal is obtained.
[0025] Andrographolide acid trihydrate single crystal 3.2g is obtained. The yield is 64%, the content calculated by HPLC peak area normalization method is 99.4%( Figure 2 , Table 1).
[0026] Table 1 HPLC determination results of andrographolide acid trihydrate single crystal peak table
[0027]
[0028] The andrographolide trihydrate single crystal prepared in this embodiment is a homogeneous and stable solid, appearing as a colorless, transparent, elongated granular solid. Its crystal structure characteristics are as follows: Figure 1 As shown in Figure 3, its chemical formula is C. 20 H 32 O6.3(H2O), with a formula weight of 422.50, an orthorhombic crystal system, and a space group of P212121, α=90°, β=90°, γ=90°, Z = 4. Its X-ray single-crystal diffraction data are shown in Table 2. From Table 2 and... Figure 1 It can be seen that the structural unit of the andrographolide trihydrate single crystal contains one andrographolide molecule and three water molecules, all of which are hydrogen-bonded. The andrographolide trihydrate single crystal exhibits a three-dimensional supramolecular structure formed by hydrogen bonds between molecules; its unit cell packing diagram is shown below. Figure 3 As shown in Formula I, C3, C4, and C9 are in the R configuration, and C5, C10, and C14 are in the S configuration.
[0029]
[0030] Table 2. X-ray single-crystal diffraction data of single crystal of andrographolide trihydrate.
[0031]
[0032] Example 2: Solubility test of capsules
[0033] 50 mg of andrographolide acid, obtained by drying in methanol using a simple modified method according to existing technology (Han Guang, Zeng Chao, Du Gangjun, et al. Synthesis of andrographolide derivatives and their anti-inflammatory and immunomodulatory activities [J]. Chinese Traditional and Herbal Drugs, 2006, 37(12):1771-1775), was finely ground, and 149 mg of microcrystalline cellulose and 1 mg of magnesium stearate were added. The mixture was then filled into one empty hard capsule to obtain capsule 1. A total of 6 capsules were prepared.
[0034] Take 50 mg of andrographolide trihydrate single crystal obtained in Example 1, grind it into a fine powder, add 149 mg of microcrystalline cellulose and 1 mg of magnesium stearate, mix well, and fill into one hollow hard capsule to obtain capsule preparation, which is designated as capsule 2. A total of 6 capsules were prepared.
[0035] Dissolution test of the capsules was carried out by the paddle method (Chinese Pharmacopoeia 2020, fourth part, general rule 0931 dissolution and release test) with 500 mL water as the dissolution medium, the rotation speed was 100 revolutions per minute, and the sample was taken at 45 min. The dissolution of each capsule was determined by spectrophotometry at a wavelength of 225 nm. Six capsules of capsule 1 and six capsules of capsule 2 were tested, and the average value of the test results was taken as the dissolution of each capsule at 45 min.
[0036] The results show that the dissolution of capsule 1 is 77.7% and the dissolution of capsule 2 is 96.5% in the dissolution medium water. It can be seen that the dissolution of capsule 2 prepared from the andrographolide acid trihydrate single crystal is significantly higher than that of capsule 1 prepared from the product obtained from the methanol solution.
[0037] According to conventional experimental techniques, it is proved that the andrographolide acid trihydrate single crystal prepared in Example 1 has an anti-inflammatory effect.
Claims
1. A single crystal of andrographolide trihydrate, characterized in that... The chemical formula is C 20 H 32 O6.3(H2O), formula weight 422.50, crystal structure orthorhombic, space group [missing information]. α=90°, β=90°, γ=90°, Z = 4; Chemical structural formula as shown in formula (I):
2. The method for preparing a single crystal of andrographolide trihydrate as described in claim 1, characterized in that... Includes the following steps: Andrographolide and potassium hydroxide were added to an 80%-90% ethanol aqueous solution (12 times the mass of andrographolide) at a molar ratio of 1:
1. The reaction was carried out, the solvent was recovered under reduced pressure and dried, and water (10 times the mass of andrographolide) was added to dissolve the product. The solution was filtered, and the pH of the filtrate was adjusted to 6-7 with dilute hydrochloric acid. The solution was allowed to stand for 30 minutes, and a precipitate was formed. The precipitate was filtered, and the filter cake was dissolved in an 90%-99.5% ethanol aqueous solution (10 times the mass of andrographolide). The solution was separated using an octadecylsilane-bonded silica gel preparative column. The solution was eluted with a gradient of 20% acetonitrile aqueous solution (0 min), increasing at a rate of 1.5% per min to 35% per min. The 30%-35% acetonitrile aqueous solution eluent was collected, the solvent was evaporated, crystals were precipitated, filtered, and dried under vacuum at room temperature to obtain single crystals of andrographolide trihydrate.