Phenylethyl resorcinol betaine eutectic crystal as well as preparation method and application thereof

Abstract

The invention provides a phenethyl resorcinol betaine eutectic crystal as well as a preparation method and application thereof, and belongs to the technical field of eutectic crystal manufacturing. The structural formula of the phenethyl resorcinol betaine eutectic crystal is shown as a formula I. The phenethyl resorcinol betaine eutectic crystal has a good whitening effect and also has good water solubility, so that the phenethyl resorcinol betaine eutectic crystal has ideal bioavailability and compatibility.

Description

Technical Field

[0001] The present application relates to the technical field of eutectic manufacturing, and in particular to a phenethylresorcinol betaine eutectic and a preparation method and application thereof. Background Art

[0002] Phenethyl resorcinol can effectively inhibit the activity of tyrosinase (tyrosinase is the key enzyme in the formation of melanin). In addition, phenethyl resorcinol can also inhibit the formation of a large number of oxygen free radicals caused by ultraviolet radiation (oxygen free radicals can promote the formation of melanin), so phenethyl resorcinol has a good whitening and freckle removal effect. However, phenethyl resorcinol has poor water solubility and is almost insoluble in water. Its extremely low solubility leads to low bioavailability and poor compatibility (it can only be used with some polyols and polar oils. The presence of polyols and oils will make the texture of the formulated product thick and viscous, making it difficult to apply to products of different dosage forms). Therefore, although the mechanism of action of phenethyl resorcinol is clear and its efficacy is significant, its poor water solubility has affected its promotion and application. Summary of the invention

[0003] The purpose of the present application is to provide a phenethylresorcinol betaine cocrystal and a preparation method and application thereof. The phenethylresorcinol betaine cocrystal has a good whitening effect and also has good water solubility, so that it has a relatively ideal bioavailability and compatibility.

[0004] The embodiment of the present application is implemented as follows: In a first aspect, an embodiment of the present application provides a phenethylresorcinol betaine co-crystal, and the structural formula of the phenethylresorcinol betaine co-crystal is shown in Formula I:

[0005] Formula I.

[0006] In the above technical scheme, the amino group in betaine has a strong electronegativity and forms an inner salt structure by itself. Phenethyl resorcinol has functional groups such as a benzene ring and a phenolic hydroxyl group, so that phenethyl resorcinol can interact with betaine through intermolecular forces such as hydrogen bonds and van der Waals forces to form a crystalline material that is regularly arranged and stably exists in the same lattice. After phenethyl resorcinol and betaine form a eutectic, the crystal arrangement is different from that of phenethyl resorcinol alone, so that the phenethyl resorcinol betaine eutectic not only has the whitening effect of phenethyl resorcinol, but also has good water solubility, so that it has a more ideal bioavailability and compatibility.

[0007] In some optional embodiments, the molecular formula of phenethylresorcinol betaine cocrystal is C 19 H 25NO4, and in the phenethylresorcinol betaine eutectic, the molar ratio of phenethylresorcinol to betaine is 1:1.

[0008] In some optional embodiments, the phenethylresorcinol betaine cocrystal is a monoclinic system, the space group is P21 / c, the unit cell parameters are a=17.6546(9) Å, b=9.1649(5) Å, c=11.6028(6) Å, α=90°, β=104.814(5)°, γ=90°, Z=4, and the unit cell volume V=1814.96(17) Å 3 .

[0009] In some optional embodiments, the X-ray powder diffraction pattern of the phenethylresorcinol betaine cocrystal has characteristic peaks at 2θ angles of 5.29°±0.2°, 18.41°±0.2°, 20.81°±0.2°, 21.59°±0.2°, 26.08°±0.2° and 35.85°±0.2°.

[0010] In a second aspect, the present application provides a method for preparing the phenethylresorcinol betaine cocrystal as provided in the first aspect, comprising the following steps: S1. Dissolve phenethyl resorcinol and betaine in an organic solvent under an inert atmosphere and light-proof conditions to obtain a mixed solution. S2. Stir the mixed solution for reaction at a first preset temperature, wherein the first preset temperature is 50-80°C, so that phenethyl resorcinol and betaine react to obtain a precursor solution containing phenethyl resorcinol betaine eutectic. S3. Perform cooling and crystallization treatment, solid-liquid separation treatment and drying treatment on the precursor solution in sequence to obtain phenethyl resorcinol betaine eutectic.

[0011] According to the above process, a phenethylresorcinol-betaine eutectic as provided in the embodiment of the first aspect can be prepared, wherein the stirring reaction is carried out at 50-80° C. in order to provide a more suitable driving force so that phenethylresorcinol and betaine can react and react more thoroughly; specifically, under the combined action of mechanical force and temperature, the amino group in betaine and the hydroxyl group of phenethylresorcinol attract each other, so that hydrogen bonds and other interaction forces are generated between betaine and phenethylresorcinol, thereby combining them together, and then forming a eutectic that is regularly arranged and stably exists in the same crystal lattice.

[0012] In some optional embodiments, under an inert atmosphere and light-proof conditions, dissolving phenethyl resorcinol and betaine in an organic solvent to obtain a mixed solution comprises: In an inert atmosphere and under light-proof conditions, phenethyl resorcinol is firstly dissolved in an organic solvent to obtain a mixed solution intermediate, and then betaine is dissolved in the mixed solution intermediate to obtain a mixed solution.

[0013] In the above technical solution, the poorly soluble and easily deteriorating phenethyl resorcinol is first dissolved in an organic solvent, and then the relatively stable and easily soluble betaine is dissolved, which has the advantages of a more reasonable sample addition order and easy operation.

[0014] In some optional embodiments, the step of first dissolving phenethylresorcinol in an organic solvent is performed under ultrasonic conditions.

[0015] In the above technical solution, the vibration energy of ultrasound can reduce the interaction force between molecules in the liquid, thereby lowering the energy threshold for solute dissolution, thereby accelerating the dissolution rate and shortening the dissolution time.

[0016] In some optional embodiments, the ultrasonic frequency is 20-60 kHz, and the ultrasonic power is 700-6000 W.

[0017] In the above technical solution, the ultrasonic frequency and the ultrasonic power are limited within the above ranges respectively, so that phenethyl resorcinol can be dissolved in the organic solvent more efficiently and thoroughly.

[0018] In some optional embodiments, the step of dissolving betaine in the mixed solution intermediate is performed at a second preset temperature and under stirring conditions, wherein the second preset temperature is 50-80°C.

[0019] In the above technical solution, dissolving betaine under heating conditions can improve its dissolution efficiency. In addition, the temperature of the mixed solution can reach the reaction temperature in advance, thereby omitting the process of heating the temperature to the reaction temperature, so as to further improve the preparation efficiency of the eutectic.

[0020] In some optional embodiments, in the mixed solution, the molar ratio of phenethyl resorcinol to betaine is 1:(0.9-1.2), and / or the mass ratio of phenethyl resorcinol to the organic solvent is 1:(5-10).

[0021] In the above technical scheme, the molar ratio of phenethylresorcinol to betaine in the mixed solution is limited within the above range, so that a eutectic product with a molar ratio closer to 1:1 can be obtained; and the mass ratio of phenethylresorcinol to the organic solvent in the mixed solution is limited within the above range, so that phenethylresorcinol can be better dissolved and dispersed.

[0022] In some optional embodiments, in the step of stirring the mixed solution at a first preset temperature, the first preset temperature is 70-80° C., and the reaction time is 2-6 h.

[0023] In the above technical scheme, the reaction temperature is further limited to the range of 70~80°C and the reaction time is limited to the range of 2~6 h, which can provide more suitable reaction conditions, thereby obtaining a eutectic product with higher purity and yield.

[0024] In some optional embodiments, the step of cooling and crystallizing includes: cooling the precursor solution to 0-10° C., and then maintaining the temperature unchanged for crystallizing.

[0025] In the above technical solution, the crystallization treatment is carried out at 0-10°C, which has the advantage of higher crystallization efficiency.

[0026] In some optional embodiments, the crystallization process is carried out under stirring conditions.

[0027] In the above technical solution, the crystallization process is carried out under stirring conditions so that the crystal growth state is more controllable, thereby obtaining a eutectic product with better particle size uniformity.

[0028] In some optional embodiments, during the crystallization process, the stirring speed is 50-600 rpm.

[0029] In the above technical solution, during the crystallization process, the adjustable range of the stirring speed is relatively wide, which is convenient for adaptive adjustment according to the volume of the mixed solution and the volume of the reaction container.

[0030] In a third aspect, an embodiment of the present application provides an application of the phenethylresorcinol betaine co-crystal provided in the embodiment of the first aspect in the preparation of medicines, cosmetics or skin care products. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 This is a schematic diagram of the X-ray single crystal diffraction structure of the phenethylresorcinol betaine cocrystal of Example 1 of the present application; Figure 2 This is the H NMR spectrum of the phenethylresorcinol betaine cocrystal of Example 1 of the present application; Figure 3 This is the NMR carbon spectrum of the phenethylresorcinol betaine cocrystal of Example 1 of the present application; Figure 4The infrared spectra of the phenethylresorcinol betaine cocrystal, phenethylresorcinol and betaine of Example 1 of the present application; Figure 5 A scanning electron micrograph of phenethyl resorcinol provided for this application; Figure 6 A scanning electron microscope image of betaine provided in this application; Figure 7 This is a scanning electron microscope image of the phenethylresorcinol betaine cocrystal of Example 1 of the present application; Figure 8 This is a scanning electron microscope image of the phenethylresorcinol betaine cocrystal of Example 4 of the present application; Fig. 9 is the X-ray powder diffraction pattern of the phenethylresorcinol betaine cocrystal of Example 1 of the present application; Fig.10 The cumulative penetration result graph of phenethyl resorcinol per unit area provided in this application; Fig.11 The inhibition curve of the phenethylresorcinol betaine co-crystal provided in the present application on the inhibition of tyrosinase (bisphenol) activity; Fig.12 The inhibition curve of tyrosinase (bisphenol) activity inhibition by phenethyl resorcinol provided in the present application; Fig.13 The inhibition graph of tyrosinase content by different types of test substances provided in this application; Fig.14 This is a graph showing the inhibition of melanin content by different types of test substances provided in this application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0034] It should be noted that “and / or” in this application, such as “Feature 1 and / or Feature 2”, refers to the three situations of “Feature 1” alone, “Feature 2” alone, or “Feature 1” plus “Feature 2”.

[0035] In addition, in the description of the present application, unless otherwise specified, the meaning of "multiple" in "one or more" refers to two or more; the range of "value a~value b" includes the two end values ​​"a" and "b", and the "unit" in "value a~value b+unit" represents the "unit" of both "value a" and "value b".

[0036] The following is a detailed description of a phenethylresorcinol betaine eutectic and its preparation method and application in an embodiment of the present application.

[0037] In a first aspect, an embodiment of the present application provides a phenethylresorcinol betaine co-crystal, and the structural formula of the phenethylresorcinol betaine co-crystal is shown in Formula I:

[0038] Formula I.

[0039] In the present application, the amino group in betaine has a strong electronegativity and forms an inner salt structure by itself. Phenethyl resorcinol has functional groups such as a benzene ring and a phenolic hydroxyl group, so that phenethyl resorcinol can interact with betaine through intermolecular forces such as hydrogen bonds and van der Waals forces to form a crystalline material that is regularly arranged and stably exists in the same lattice. After phenethyl resorcinol and betaine form a eutectic, the crystal arrangement is different from that of phenethyl resorcinol alone, so that the phenethyl resorcinol betaine eutectic not only has the whitening effect of phenethyl resorcinol, but also has good water solubility, so that it has a more ideal bioavailability and compatibility.

[0040] It should be noted that betaine is an alkaloid with the chemical name N,N,N-trimethylglycine and a chemical structure similar to amino acids. Betaine is widely present in animals and plants and plays a very important role in the metabolism of nutrients. It is a byproduct of metabolism and a very important osmotic regulator. It promotes fat metabolism and the formation of intracellular proteins, revitalizes cells, keeps the skin young and energetic, and maintains the elasticity of the skin. In addition, betaine has good biocompatibility and is easily soluble in water. It is a carrier of water molecules. When physical conditions change, water molecules will be released into the surrounding environment and then absorbed and utilized by cells to achieve a hydrating effect.

[0041] As an example, the molecular formula of phenethylresorcinol betaine cocrystal is C 19 H 25 NO4, and in the phenethylresorcinol betaine eutectic, the molar ratio of phenethylresorcinol to betaine is 1:1.

[0042] As an example, the phenethylresorcinol betaine eutectic is monoclinic with space group P21 / c, unit cell parameters a=17.6546(9) Å, b=9.1649(5) Å, c=11.6028(6) Å, α=90°, β=104.814(5)°, γ=90°, Z=4, unit cell volume V=1814.96(17) Å 3 .

[0043] As an example, the X-ray powder diffraction pattern of phenethylresorcinol betaine cocrystal has characteristic peaks at 2θ angles of 5.29°±0.2°, 18.41°±0.2°, 20.81°±0.2°, 21.59°±0.2°, 26.08°±0.2° and 35.85°±0.2°.

[0044] In order to better understand the technical solution, the present application simulates and provides a schematic diagram of the molecular structure of phenethylresorcinol betaine cocrystal (see Figure 1 ).

[0045] In a second aspect, the present application provides a method for preparing the phenethylresorcinol betaine cocrystal as provided in the first aspect, comprising the following steps: S1 Under an inert atmosphere and light-proof conditions, phenethyl resorcinol and betaine are dissolved in an organic solvent to obtain a mixed solution. S2 The mixed solution is stirred and reacted at a first preset temperature, wherein the first preset temperature is 50-80°C (for example, but not limited to, any one of 50°C, 55°C, 60°C, 65°C, 70°C, 75°C and 80°C or a range between any two of them), so that phenethyl resorcinol and betaine react to obtain a precursor solution containing phenethyl resorcinol betaine eutectic; S3 The precursor solution is subjected to cooling and crystallization treatment, solid-liquid separation treatment and drying treatment in sequence to obtain phenethyl resorcinol betaine eutectic.

[0046] In the present application, a phenethylresorcinol-betaine eutectic as provided in the first aspect of the embodiment can be prepared according to the above process, wherein the stirring reaction is carried out at 50-80° C. in order to provide a more suitable driving force so that phenethylresorcinol and betaine can react and react more thoroughly; specifically, under the combined action of mechanical force and temperature, the amino group in betaine and the hydroxyl group of phenethylresorcinol attract each other, so that hydrogen bonds and other interaction forces are generated between betaine and phenethylresorcinol, thereby combining together to form a eutectic that is regularly arranged and stably exists in the same lattice.

[0047] It should be noted that the type of organic solvent is not limited and can be selected according to the conventional method in the art. For example, the organic solvent can be at least one of isopropanol, ethanol, acetone and methanol.

[0048] It should be noted that the form in which phenethylresorcinol and betaine are dissolved in the organic solvent is not limited, for example, they can be added to the organic solvent simultaneously for dissolution, or they can be added to the organic solvent stepwise for dissolution.

[0049] As an example, under an inert atmosphere and light-proof conditions, the steps of dissolving phenethyl resorcinol and betaine in an organic solvent to obtain a mixed solution include: In an inert atmosphere and under light-proof conditions, phenethyl resorcinol is firstly dissolved in an organic solvent to obtain a mixed solution intermediate, and then betaine is dissolved in the mixed solution intermediate to obtain a mixed solution.

[0050] In this embodiment, the poorly soluble and easily deteriorating phenethyl resorcinol is first dissolved in an organic solvent, and then the relatively stable and easily soluble betaine is dissolved, which has the advantages of a more reasonable sample addition order and easy operation.

[0051] As an example, the step of first dissolving phenethylresorcinol in an organic solvent is performed under ultrasonic conditions.

[0052] In this embodiment, the vibration energy of the ultrasonic wave can reduce the interaction force between molecules in the liquid, thereby lowering the energy threshold for solute dissolution, thereby accelerating the dissolution rate and shortening the dissolution time.

[0053] As an example, the ultrasonic frequency is 20~60 kHz, for example but not limited to the ultrasonic frequency is any point value of 20 kHz, 30 kHz, 40 kHz, 50 kHz, and 60 kHz, or a range value between any two of them; the ultrasonic power is 700~6000 W, for example but not limited to the ultrasonic power is any point value of 700 W, 1000 W, 2000 W, 3000 W, 4000 W, 5000 W and 6000 W, or a range value between any two of them.

[0054] In this embodiment, the ultrasonic frequency and the ultrasonic power are respectively limited within the above ranges, so that phenethyl resorcinol can be dissolved in the organic solvent more efficiently and thoroughly.

[0055] As an example, the step of dissolving betaine in the mixed solution intermediate is performed at a second preset temperature and under stirring conditions, wherein the second preset temperature is 50-80°C, for example but not limited to any one of 50°C, 55°C, 60°C, 65°C, 70°C, 75°C and 80°C or a range between any two of them.

[0056] In this embodiment, dissolving betaine under heating conditions can improve its dissolution efficiency. In addition, the temperature of the mixed solution can reach the reaction temperature in advance, thereby omitting the process of heating the temperature to the reaction temperature, so as to further improve the preparation efficiency of the eutectic.

[0057] As an example, in the mixed solution, the molar ratio of phenethyl resorcinol to betaine is 1:(0.9~1.2), for example but not limited to the molar ratio of 1:0.9, 1:0.95, 1:1, 1:1.15 and 1:1.2, or a range between any two of them; and / or, the mass ratio of phenethyl resorcinol to the organic solvent is 1:(5~10), for example but not limited to the mass ratio of 1:5, 1:6, 1:7, 1:8, 1:9 and 1:10, or a range between any two of them.

[0058] In this embodiment, the molar ratio of phenethylresorcinol to betaine in the mixed solution is limited within the above range, so that a eutectic product with a molar ratio closer to 1:1 can be obtained; and the mass ratio of phenethylresorcinol to the organic solvent in the mixed solution is limited within the above range, so that phenethylresorcinol can be better dissolved and dispersed.

[0059] As an example, in the step of stirring the mixed solution to react at a first preset temperature, the first preset temperature is 70~80℃, for example but not limited to the temperature of 70℃, 71℃, 72℃, 73℃, 74℃, 75℃, 76℃, 77℃, 78℃, 79℃ and 80℃, any one point value or a range value between any two of them; the reaction time is 2~6 h, for example but not limited to the reaction time of 2 h, 3 h, 4 h, 5 h and 6 h, any one point value or a range value between any two of them.

[0060] In this embodiment, the reaction temperature is further limited to the range of 70-80° C. and the reaction time is limited to the range of 2-6 h, which can provide more suitable reaction conditions, thereby obtaining a eutectic product with higher purity and yield.

[0061] It should be noted that the temperature of the crystallization treatment is not limited as long as the phenethylresorcinol betaine eutectic in the precursor solution can be precipitated.

[0062] As an example, the step of cooling and crystallizing treatment includes: cooling the precursor solution to 0~10℃ (for example, but not limited to, the temperature is any point value among 0℃, 1℃, 2℃, 3℃, 4℃, 5℃, 6℃, 7℃, 8℃, 9℃ and 10℃, or the range value between any two of them), and then maintaining the temperature unchanged for crystallization treatment.

[0063] In this embodiment, the crystallization treatment is performed at 0-10° C., which has the advantage of higher crystallization efficiency.

[0064] As an example, the crystallization process is performed under stirring conditions.

[0065] In this embodiment, the crystallization process is carried out under stirring conditions so that the crystal growth state is more controllable, thereby obtaining a eutectic product with better particle size uniformity.

[0066] As an example, during the crystallization process, the stirring speed is 50~600 rpm, for example but not limited to any one of 50 rpm, 100 rpm, 200 rpm, 300 rpm, 400 rpm, 500 rpm and 600 rpm or a range between any two of them.

[0067] In this embodiment, during the crystallization process, the adjustable range of the stirring speed is relatively wide, which facilitates adaptive adjustment according to the volume of the mixed solution and the volume of the reaction container.

[0068] In other possible implementations, during the crystallization process, a static crystallization method may be adopted.

[0069] As an example, the drying method is vacuum drying, wherein the drying temperature is 50~55°C, for example but not limited to the temperature being any one of 50°C, 51°C, 52°C, 53°C, 54°C and 55°C or a range between any two thereof; the drying time is 12~48 h, for example but not limited to the drying time being any one of 12 h, 15 h, 30 h, 40 h and 48 h or a range between any two thereof.

[0070] In this embodiment, vacuum drying is adopted, which has the advantages of lower drying temperature and less prone to product denaturation.

[0071] It should be noted that any process or step not specifically described or limited in the preparation process of phenethylresorcinol betaine cocrystal may be arranged according to conventional selection in the art.

[0072] In a third aspect, an embodiment of the present application provides an application of the phenethylresorcinol betaine co-crystal provided in the embodiment of the first aspect in the preparation of medicines, cosmetics or skin care products.

[0073] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0074] Example 1 The present application provides a method for preparing phenethylresorcinol betaine eutectic, comprising the following steps: S1 In an inert atmosphere and light-proof conditions, 50 g of phenethyl resorcinol and 300 g of isopropanol were added to a reaction container, and then dissolved under ultrasonic conditions, wherein the ultrasonic frequency was 40 kHz and the ultrasonic power was 1500 W, until the phenethyl resorcinol was completely dissolved to obtain a mixed solution intermediate; then 28.5 g of betaine was added to the mixed solution intermediate so that the molar ratio of phenethyl resorcinol to betaine was 1:1, and then dissolved by stirring at 80°C, wherein the stirring speed was 600 rpm, until the betaine was completely dissolved to obtain a mixed solution.

[0075] S2: maintaining the temperature of the mixed solution unchanged (ie, 80° C.) and stirring at 600 rpm for 3 h to allow phenethylresorcinol and betaine to react, thereby obtaining a precursor solution containing phenethylresorcinol-betaine eutectic.

[0076] S3 The temperature of the precursor solution was cooled to 5°C and stirred at 400 rpm for crystallization for 3 h; then solid-liquid separation was performed, and the obtained solid was dried in a vacuum drying oven, wherein the drying time was 20 h and the drying temperature was 50°C, to obtain phenethylresorcinol betaine cocrystals with a yield of 88.9%.

[0077] Example 2 The present embodiment provides a method for preparing phenethylresorcinol betaine cocrystal, which differs from Example 1 only in that the molar ratio of phenethylresorcinol to betaine is 1:0.9, and the yield is 87.5%.

[0078] Example 3 The present embodiment provides a method for preparing phenethylresorcinol betaine cocrystal, which differs from Example 1 only in that the molar ratio of phenethylresorcinol to betaine is 1:1.2, and the yield is 87.1%.

[0079] Example 4 The present embodiment provides a method for preparing phenethylresorcinol betaine cocrystal, which differs from Example 1 only in that the stirring crystallization method is adjusted to a static crystallization method, and the yield is 81.1%.

[0080] Comparative Example 1 The present embodiment provides a method for preparing phenethylresorcinol betaine eutectic, which differs from Example 1 only in that all isopropanol is replaced with water.

[0081] Comparative Example 2 The present embodiment provides a method for preparing phenethylresorcinol betaine eutectic, which differs from Embodiment 1 only in that the reaction temperature in step S2 is adjusted to 40°C.

[0082] Test Example 1 Phenethylresorcinol betaine eutectics were prepared according to the preparation methods of Examples 1 to 4 and Comparative Examples 1 to 2, respectively. Then, each sample was numbered, and then, the element content of each sample was tested using an element analyzer, and the results were statistically summarized in Table 1.

[0083] Table 1

[0084] It should be noted that the theoretical value is calculated based on the standard that the molar ratio of phenethylresorcinol to betaine is 1:1.

[0085] Referring to Table 1, the test results of Examples 1 to 4 are substantially consistent with the theoretical results, indicating that Examples 1 to 4 all successfully prepared phenethylresorcinol betaine eutectic.

[0086] According to the test results of Example 1 and Comparative Example 1, if water is used as the solvent, phenethylresorcinol betaine eutectic cannot be prepared because phenethylresorcinol is difficult to be miscible with water.

[0087] It can be seen from the test results of Example 1 and Comparative Example 2 that the test results of Comparative Example 2 are quite different from the theoretical results, indicating that the prepared substance is not a eutectic. In other words, it indicates that the reaction temperature is too low, and the driving force provided is insufficient, so the phenethylresorcinol betaine eutectic cannot be successfully prepared.

[0088] Test Example 2 Qualitative Analysis of Phenethyl Resorcinol Betaine Cocrystal Test method: The phenethylresorcinol betaine eutectic obtained in Example 1 was qualitatively analyzed.

[0089] Table 2 Single crystal data of eutectic phenethyl resorcinol betaine

[0090] Table 3 Atomic coordinates and isotropic atomic displacement parameters of phenethylresorcinol betaine cocrystal

[0091] It should be noted that U(eq) is defined as one third of the trace of the orthogonal Uij tensor.

[0092] Table 4 Anisotropic atomic displacement parameters of phenethylresorcinol betaine cocrystal

[0093] It should be noted that the anisotropic atomic displacement factor power is expressed as: -2π 2 [h2 a* 2 U 11 +2hka*b*U 12 +…].

[0094] Table 5 The chemical bond lengths of phenethylresorcinol betaine cocrystal

[0095] Table 6 Bond angles of phenethylresorcinol betaine cocrystal

[0096] Table 7 Hydrogen bonding parameters of phenethylresorcinol betaine cocrystal

[0097] 1 1-X, 1-Y, -Z; 2 1-X,1 / 2+Y,-1 / 2-Z.

[0098] Table 8 Torsion angle parameters of phenethylresorcinol betaine eutectic

[0099] Table 9 Hydrogen atom coordinates of phenethylresorcinol betaine cocrystal (Å×10 4 ) and the isotropic atomic displacement parameters (Å 2 ×10 3 )

[0100] Test Example 3 H NMR spectroscopy ( 1 H-NMR) characterization Test method: The phenethylresorcinol betaine cocrystal obtained in Example 1 was subjected to H NMR spectroscopy ( 1 H-NMR) characterization, and MeOD solvent was selected as the test solvent.

[0101] See also Figure 2 From the H-NMR spectrum, we can clearly find 12 hydrogen atoms of phenethylresorcinol and 11 hydrogen atoms on betaine. The rest are a small amount of residual water peaks and deuterated reagent peaks. No obvious impurity peaks are seen. This shows that in the phenethylresorcinol-betaine cocrystal, phenethylresorcinol and betaine exist in a molar ratio of 1:1.

[0102] Test Example 4 C NMR spectroscopy ( 13 C-NMR) characterization Test method: The phenethylresorcinol betaine cocrystal obtained in Example 1 was subjected to carbon nuclear magnetic resonance spectroscopy ( 13 C-NMR) characterization, and MeOD solvent was selected as the test solvent.

[0103] See also Figure 3 The test results show that phenethylresorcinol and betaine in the phenethylresorcinol-betaine eutectic are present in a molar ratio of 1:1.

[0104] Test Example 5 Infrared spectroscopy characterization Test method: The phenethylresorcinol betaine cocrystal obtained in Example 1 was characterized by infrared spectroscopy, wherein the test parameter was transmittance and the test wave number was 400 cm -1 ~4000cm -1 , the test mode is ATR.

[0105] See also Figure 4 The infrared spectrum of phenethylresorcinol-betaine cocrystal has different absorption peaks from betaine and phenethylresorcinol, and is not a simple superposition of the characteristic peaks of the two precursors, indicating that phenethylresorcinol and betaine form a cocrystal, which is a new structure.

[0106] Test Example 6 Morphological characterization Test method: The phenethylresorcinol, betaine, and the phenethylresorcinol betaine co-crystals obtained in Example 1 and Example 4 were characterized by scanning electron microscopy.

[0107] See also Figure 5 , Figure 6 and Figure 7 The morphology of the phenethylresorcinol betaine cocrystal is blocky, which is completely different from the morphology of phenethylresorcinol and betaine. The particle size is about 10~50 μm, and the particle uniformity is good.

[0108] See also Figure 7 and Figure 8 Compared with stirred crystallization, the particles of phenethylresorcinol betaine eutectic obtained by static crystallization are larger, the surface is rougher and the particle uniformity is poorer, indicating that the stirred crystallization method is better.

[0109] Test Example 7 X-ray powder diffraction (XRD) test Test method: The phenethylresorcinol betaine cocrystal obtained in Example 1 was subjected to an X-ray powder diffraction test, wherein the test conditions were 5° / min and the test range was 3°~50°.

[0110] See also Fig. 9 ,The results showed that the phenethylresorcinol betaine cocrystal had characteristic peaks at 2θ angles of approximately 5.29°±0.2°, 18.41°±0.2°, 20.81°±0.2°, 21.59°±0.2°, 26.08°±0.2°, and 35.85°±0.2°.

[0111] Test Example 8 Water solubility test Test method: The phenethylresorcinol betaine cocrystals obtained in Examples 1 to 3 were dissolved in water to prepare a supersaturated solution under magnetic stirring. After sampling and filtration, the content of phenethylresorcinol in the phenethylresorcinol betaine cocrystals was detected by high performance liquid chromatography, and the results were statistically shown in Table 10.

[0112] Table 10

[0113] Referring to Table 10, the water solubility of phenethyl resorcinol in the phenethyl resorcinol betaine cocrystal is >550 ppm, which is much higher than the water solubility of phenethyl resorcinol itself (<10 ppm, data from ACD database), indicating that the water solubility of phenethyl resorcinol is greatly improved after phenethyl resorcinol and betaine form a cocrystal.

[0114] Test Example 9 Transdermal delivery performance testing Test substances: 1% aqueous solution of phenethylresorcinol betaine eutectic obtained in Example 1 (10% propylene glycol), 0.65% aqueous solution of phenethylresorcinol (10% propylene glycol), saturated aqueous solution of phenethylresorcinol betaine eutectic obtained in Example 1, saturated aqueous solution of phenethylresorcinol.

[0115] Test method: The porcine skin model was used to detect the skin permeation at different times and to evaluate the transdermal delivery efficiency of the main components in the samples.

[0116] (1) Microscopic examination: Select undamaged pig skin under a dissecting microscope, cut skin of the same size, wash it once with sodium chloride solution, and absorb the surface moisture with filter paper.

[0117] (2) Fix the skin: Fix the skin on the Franz diffusion cell with the stratum corneum facing the dosing chamber and the dermis facing the receiving chamber. Add 15 mL of sodium chloride solution (10% ethanol) into the receiving chamber and remove bubbles to ensure that there are no bubbles between the dermis and the receiving solution.

[0118] (3) Drug administration: Turn on the instrument in advance and adjust the water bath temperature to 37±1℃. Add 1.0 mL of drug into the drug administration chamber, seal it with sealing film and tin foil to prevent liquid evaporation. The effective penetration area is 1.13 cm 2 .

[0119] (4) Infiltration: Set the stirring speed to 350 rpm / min.

[0120] (5) Sampling: At 3, 6, 21, and 24 h, 10 mL of subcutaneous receiving fluid was pipetted into a 5.0 mL EP tube and then 1.0 mL of sodium chloride solution (10% ethanol) was added to the receiving pool using a pipette.

[0121] (6) Detection: The above samples were filtered through a 0.22 μm organic membrane and then tested by HPLC to calculate the permeation per unit area. The results were then statistically reported in Table 11. At the same time, a graph was drawn based on the statistical results.

[0122] Table 11

[0123] See Table 11 and Fig.10 , whether in saturated aqueous solution or unsaturated aqueous solution, the cumulative permeation amount of phenethylresorcinol betaine cocrystal is much higher than that of phenethylresorcinol.

[0124] Test Example 10 Tyrosinase activity inhibition test (1) Experimental principle: In the biosynthesis of skin melanin, tyrosinase is a key enzyme that acts on DOPA to form DOPA quinone, which then undergoes a series of reactions to form melanin. In a Na2HPO4-citrate buffer solution at pH 6.8, tyrosinase can catalyze the conversion of DOPA into DOPA quinone, and the absorbance can be measured at 475 nm on a spectrophotometer. Raw materials that inhibit tyrosinase activity can reduce the conversion of DOPA into DOPA quinone, thereby reducing the absorbance. The inhibitory effect of the raw materials on tyrosinase activity can be evaluated based on the change in absorbance.

[0125] (2) Experimental materials: phenethylresorcinol betaine co-crystal obtained in Example 1, phenethylresorcinol alone and kojic acid (positive control group).

[0126] (3) Test method: T / SHRH 015-2018 "Cosmetics - Tyrosinase Activity Inhibition Test Method", and then the test results are statistically summarized in Tables 12 and 13 respectively, and at the same time, a graph is drawn based on the statistical results.

[0127] Table 12

[0128] *The data in the table are mean ± relative deviation.

[0129] *Statistical method: The t-test method was used for analysis, and the significance level α = 0.05; P ≥ 0.05 indicates no statistical difference; 0.01 < P < 0.05 indicates significant difference; P < 0.01 indicates very significant difference; P < 0.001 indicates extremely significant difference.

[0130] Table 13

[0131] *The data in the table are mean ± relative deviation.

[0132] *Statistical method: The t-test method was used for analysis, and the significance level α = 0.05; P ≥ 0.05 indicates no statistical difference; 0.01 < P < 0.05 indicates significant difference; P < 0.01 indicates very significant difference; P < 0.001 indicates extremely significant difference.

[0133] Refer to Table 12 and Table 13, Fig.11 and Fig.12 , the half inhibitory concentration IC 50 = 0.040 mg / mL (95% confidence interval IC50: 0.037 mg / mL ~ 0.044 mg / mL) of phenethyl resorcinol betaine eutectic on the inhibition of tyrosinase (bisphenol) activity has whitening effect. The half inhibitory concentration IC 50 = 0.037 mg / mL (95% confidence interval IC50: 0.034 mg / mL ~ 0.040 mg / mL) of phenethyl resorcinol on the inhibition of tyrosinase (bisphenol) activity has whitening effect. It shows that the ability of phenethyl resorcinol betaine eutectic and phenethyl resorcinol to inhibit tyrosinase (bisphenol) activity is similar. However, under the same test concentration, since the content of phenethyl resorcinol in phenethyl resorcinol betaine eutectic is less, it shows that phenethyl resorcinol betaine eutectic can also exert good whitening effect at lower addition amount and less irritation.

[0134] Test Example 11 Detection of the inhibitory ability of human melanocyte tyrosinase (1) Experimental principle: The inhibition of melanin production is mainly achieved through two aspects, one is to inhibit the activity of tyrosinase, and the other is to inhibit the signal pathway of melanin production. Some whitening agents, such as kojic acid and its derivatives and arbutin, inhibit the production of melanin by inhibiting the activity of tyrosinase. There are also inhibitors that act on the melanin production signal pathway, such as inhibitors of α-melanocyte stimulating hormone (α-MSH) receptor MCIR protein. In addition, products with antioxidant effects can reduce dopaquinone to levodopa, which can be used in the development of whitening products to a certain extent. This method uses α-MSH to induce melanocytes and uses colorimetry to detect the effect of samples on tyrosinase inhibition to evaluate its efficacy.

[0135] (2) Experimental materials: the eutectic of phenethylresorcinol betaine obtained in Example 1, a physical mixture of phenethylresorcinol betaine in a molar ratio of 1:1, phenethylresorcinol and kojic acid (positive control).

[0136] (3) Test method: Inoculate cells into 96-well plates and culture for 18-24 h; remove the original culture medium, add culture medium containing different concentrations of the test substance and α-MSH, and culture continuously for 3 days; after exposure, remove the culture medium, wash twice with PBS, add 90 μL of cell lysis solution, and treat by repeated freezing and thawing to lyse the cells; preheat the plate at 37°C for 5 min, quickly add 10 μL of L-DOPA solution, shake and measure the absorbance at 405 nm. After reacting at 37°C for 30 min, measure the absorbance again. Data were analyzed using SPSS and expressed as mean ± standard deviation. If p < 0.05, the difference was considered statistically significant. The test results were then statistically reported in Tables 14 and 15, and plotted based on the statistical results.

[0137]

[0138] Table 14

[0139] Note: # indicates that the difference is statistically significant compared with the blank control group (NC) (p<0.05); *Indicates that the difference was statistically significant compared with the model control group (M) (p<0.05).

[0140] Table 15

[0141] See Tables 14, 15 and Fig.13Compared with the blank control group (NC), the tyrosinase activity of the model control group (M) was significantly increased (p<0.05); compared with the model control group, the relative content of tyrosinase activity of the positive control group (PC) was significantly decreased (p<0.05), indicating that the model was successfully established. Compared with the model control group, the relative content of tyrosinase activity in the sample "phenylethylresorcinol betaine cocrystal" at the test concentrations of 0.00075 mg / mL and 0.00045 mg / mL was significantly reduced (p<0.05), which was reduced by 23.59% and 17.85% respectively, which had the effect of inhibiting tyrosinase activity; the relative content of tyrosinase activity in the sample "phenylethylresorcinol betaine physical mixture" at the test concentrations of 0.00075 mg / mL and 0.00045 mg / mL was significantly reduced (p<0.05), which was reduced by 21.50% and 11.16% respectively, which had the effect of inhibiting tyrosinase activity; the relative content of tyrosinase activity in the sample "phenylethylresorcinol" at the test concentrations of 0.0005 mg / mL and 0.0003 mg / mL was significantly reduced (p<0.05), which was reduced by 17.41% and 12.62% respectively, which had the effect of inhibiting tyrosinase activity. The significant differences between the test substance groups with the same concentration showed that the phenethylresorcinol betaine cocrystal had a significant difference from phenethylresorcinol at a concentration of 0.00075 mg / mL; the phenethylresorcinol betaine cocrystal had a significant difference from the physical mixture of phenethylresorcinol betaine and phenethylresorcinol at a concentration of 0.00045 mg / mL, indicating that the phenethylresorcinol betaine cocrystal had the best effect in inhibiting tyrosinase activity.

[0142] Test Example 12 Detection of melanin production inhibition ability in human melanocytes (1) Experimental principle: The inhibition of melanin production is mainly achieved in two ways, one is to inhibit the activity of tyrosinase, and the other is to inhibit the signal pathway of melanin production. Some whitening agents, such as kojic acid and its derivatives and arbutin, inhibit the production of melanin by inhibiting the activity of tyrosinase. There are also inhibitors that act on the melanin production signal pathway, such as inhibitors of the α-melanocyte stimulating hormone (α-MSH) receptor MCIR protein. In addition, products with antioxidant effects can reduce dopaquinone to levodopa, which can be used in the development of whitening products to a certain extent. This method uses α-MSH to induce melanocytes and uses colorimetry to detect the effect of the sample on the inhibition of melanin production to evaluate its efficacy.

[0143] (2) Experimental materials: the eutectic of phenethyl resorcinol betaine obtained in Example 1, a physical mixture of phenethyl resorcinol betaine at a molar ratio of 1:1, and kojic acid (positive control).

[0144] (3) Test method: The cells were inoculated into 6-well plates and cultured for 18-24 h; the original culture medium was removed, and the culture medium containing different concentrations of the test substance and α-MSH was added, and the culture was continued for 5 days, with the medium changed once in the middle; at the end of exposure, the culture medium was removed, washed once with PBS, and the cells in each well were collected by cell scraping; 1 mol / L NaOH solution (containing 10% DMSO) was added to dissolve the cells and obtain cell fluid; the cell fluid was heated at 80°C for 30 min to lyse the melanosomes; the cell fluid was taken to measure the absorbance value at a wavelength of 490 nm. The data were analyzed using SPSS and expressed as mean ± standard deviation. If p < 0.05, the difference was considered statistically significant, and then the test results were statistically reported in Tables 16 and 17, and plotted according to the test results.

[0145]

[0146] Table 16

[0147] Note: # indicates that the difference is statistically significant compared with the blank control group (NC) (p<0.05); *Indicates that the difference is statistically significant compared with the model control group (M) (p<0.05).

[0148] Table 17

[0149] See Table 16, Table 17 and Fig.14 Compared with the blank control group (NC), the relative content of melanin in the model control group (M) was significantly increased (p<0.05); compared with the model control group, the relative content of melanin in the positive control group (PC) was significantly decreased (p<0.05), indicating that the model was successfully established. Compared with the model control group, the relative content of melanin in the sample "phenylethyl resorcinol betaine eutectic" was significantly reduced at a test concentration of 0.00025 mg / mL (p<0.05), a decrease of 19.66%, which had the effect of inhibiting melanin production; the relative content of melanin in the sample "phenylethyl resorcinol betaine physical mixture" was significantly reduced at a test concentration of 0.00025 mg / mL (p<0.05), a decrease of 13.10%, which had the effect of inhibiting melanin production. There were significant differences between the phenylethyl resorcinol betaine eutectic and the phenylethyl resorcinol betaine physical mixture and phenylethyl resorcinol, indicating that the phenylethyl resorcinol betaine eutectic had a better effect of inhibiting melanin production.

[0150] Test Example 13 Irritation test (1) Experimental materials: 1% emulsion of phenethylresorcinol betaine eutectic; negative control: blank + filter disc; number of subjects: 30.

[0151] (2) Test method: Select qualified patch test equipment and use the closed patch test method. Place 0.020 g to 0.025 g of the test substance in the patch test equipment and apply it to the curved side of the subject's forearm with a low-allergenic tape. Remove the test substance after 24 hours and observe the skin reaction at 0.5, 24, and 48 hours after removal. Evaluate the stimulation intensity according to Table 18 and summarize the test results in Table 19.

[0152] Table 18

[0153] Table 19

[0154] As shown in Table 19, due to the use of the same body self-comparison method, the negative control group had a total of 30 regions, and no irritation occurred in the negative control group, proving that the experiment was effective and the results were credible. The phenethylresorcinol betaine eutectic group had no irritation at 0.5 h, 24 h, and 48 h, proving that the phenethylresorcinol betaine eutectic was mild and low in irritation.

[0155] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

Claims

1. A phenethylresorcinol betaine eutectic, characterized in that: The structural formula of the phenethylresorcinol betaine eutectic is shown in Formula I: Formula I.

2. The phenethylresorcinol betaine eutectic according to claim 1, characterized in that The molecular formula of the phenethyl resorcinol betaine eutectic is C 19 H 25 NO4, and in the phenethylresorcinol betaine eutectic, the molar ratio of the phenethylresorcinol to the betaine is 1:

1.

3. The phenethylresorcinol betaine eutectic according to claim 1, characterized in that The phenethyl resorcinol betaine eutectic is a monoclinic system, the space group is P21 / c, the unit cell parameters are a=17.6546(9) Å, b=9.1649(5) Å, c=11.6028(6) Å, α=90°, β=104.814(5)°, γ=90°, Z=4, and the unit cell volume V=1814.96(17) Å 3 .

4. The phenethylresorcinol betaine eutectic according to any one of claims 1 to 3, characterized in that In the X-ray powder diffraction pattern of the phenethylresorcinol betaine cocrystal, characteristic peaks are present at 2θ angles of 5.29°±0.2°, 18.41°±0.2°, 20.81°±0.2°, 21.59°±0.2°, 26.08°±0.2° and 35.85°±0.2°.

5. A method for preparing the phenethylresorcinol betaine eutectic as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Under an inert atmosphere and in the dark, dissolving phenethyl resorcinol and betaine in an organic solvent to obtain a mixed solution; S2 stirring the mixed solution to react at a first preset temperature, wherein the first preset temperature is 50-80° C., so that the phenethylresorcinol and the betaine react to obtain a precursor solution containing the phenethylresorcinol betaine eutectic; S3: performing cooling and crystallization treatment, solid-liquid separation treatment and drying treatment on the precursor solution in sequence to obtain the phenethylresorcinol betaine eutectic.

6. The preparation method according to claim 5, characterized in that: The step of dissolving phenethyl resorcinol and betaine in an organic solvent under an inert atmosphere and light-proof conditions to obtain a mixed solution comprises: In an inert atmosphere and under light-proof conditions, the phenethyl resorcinol is first dissolved in the organic solvent to obtain a mixed solution intermediate, and then the betaine is dissolved in the mixed solution intermediate to obtain the mixed solution.

7. The preparation method according to claim 6, characterized in that: The step of first dissolving the phenethyl resorcinol in the organic solvent is performed under ultrasonic conditions.

8. The preparation method according to claim 7, characterized in that The ultrasonic frequency is 20~60 kHz, and the ultrasonic power is 700~6000 W.

9. The preparation method according to claim 6, characterized in that: The step of dissolving the betaine in the mixed solution intermediate is performed at a second preset temperature and under stirring conditions, wherein the second preset temperature is 50-80°C.

10. The preparation method according to any one of claims 5 to 9, characterized in that: In the mixed solution, the molar ratio of the phenethyl resorcinol to the betaine is 1:(0.9-1.2), and / or the mass ratio of the phenethyl resorcinol to the organic solvent is 1:(5-10).

11. The preparation method according to any one of claims 5 to 9, characterized in that In the step of stirring the mixed solution at a first preset temperature, the first preset temperature is 70-80° C., and the reaction time is 2-6 h.

12. The preparation method according to any one of claims 5 to 9, characterized in that The step of cooling and crystallizing comprises: cooling the precursor solution to 0-10° C., and then maintaining the temperature unchanged to perform crystallization.

13. The preparation method according to claim 12, characterized in that: The crystallization treatment is carried out under stirring conditions.

14. The preparation method according to claim 13, characterized in that During the crystallization process, the stirring speed is 50-600 rpm.

15. Use of the phenethylresorcinol betaine cocrystal according to any one of claims 1 to 4 in the preparation of medicines, cosmetics or skin care products.

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