Polypeptide coupling compound as well as preparation method and application thereof

Abstract

The invention discloses a polypeptide coupling compound as well as a preparation method and application thereof, and relates to the technical field of polypeptides. The structure of the polypeptide coupling compound is shown in the specification, and the Peptide is any one polypeptide sequence as shown in SEQ ID NO. 1 to 38. The resorcinol compound is coupled with the polypeptide sequence, so that the water solubility of the resorcinol derivative is remarkably improved, the cell penetrability and the skin permeability are improved, the effective transfer of the resorcinol derivative in the skin is promoted, and meanwhile, the skin beautifying effect of polypeptide and the whitening activity of the resorcinol derivative are fused; and multiple effects of whitening, wrinkle resistance and aging resistance are realized. The polypeptide coupling compound provided by the invention is simple in structure, mild in reaction condition, easy to prepare, high in synthesis success rate and relatively high in product purity, and has a good market prospect when being applied to whitening cosmetics.

Description

Technical Field

[0001] This invention relates to the field of polypeptide technology, and in particular to a polypeptide coupling compound, its preparation method, and its application. Background Technology

[0002] The application of peptide compounds in cosmetics is constantly evolving with technological advancements and changing consumer demands. In recent years, research on active peptides has received widespread attention. Since the implementation of new cosmetic regulations in 2021, the research and development of peptide raw materials has experienced explosive growth. As of October 15, 2025, the cumulative number of registered peptide raw materials has reached 46.

[0003] Despite the rapid development of peptide raw materials, in terms of efficacy, most peptide raw materials are mainly used in anti-aging and anti-wrinkle fields. However, in the whitening field, which has huge market demand, there are not many peptide raw materials, only a few such as nonapeptide-1.

[0004] In the field of skin-whitening ingredients, resorcinol derivatives are gaining increasing attention. Examples include 4-butylresorcinol (377), isobutamidothiazolylresorcinol (Thiamidol), phenylethylresorcinol, and 4-hexylresorcinol. While these compounds offer skin-whitening effects in cosmetics, they also have some significant drawbacks, such as poor water solubility and the potential for allergic reactions and skin irritation.

[0005] In the cosmetics industry, while the use of single-function ingredients can provide clear effects in some products, it is usually difficult to meet the increasingly diverse needs of modern consumers. Consumers not only expect cosmetics to solve a specific problem, but also have concerns about the unknown risks of too many ingredients in cosmetic formulas.

[0006] As a class of highly effective active substances, peptides not only possess their own specific functions, but they can also combine with other molecules to form new compounds. These compounds may not only improve solubility but also enhance bioavailability, skin permeability, and other benefits. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a polypeptide coupling compound, its preparation method, and its application. Based on the water solubility of resorcinol compounds, the invention further expands the functions of the compounds, resulting in new raw materials with multiple effects.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, the present invention provides a polypeptide coupling compound, the structure of which is shown in formula (II): (II) In formula (II), Peptide is any polypeptide sequence shown in SEQ ID NO.1~38, and the amino group of the N-terminal amino acid of the polypeptide sequence is connected to the carboxyl group of compound (I) through an amide bond to obtain compound (II). The structure of compound (I) is shown in (I) below: (I).

[0009] Furthermore, the polypeptide sequences shown in SEQ ID NO. 1~38 are as follows: SEQ ID NO.1: H-Ala-Gly-Tyr-Leu-Leu-Gly-Lys-Ile-Asn-Leu-Lys-Ala-Cys-Ala-Ala-Leu-Ala-Lys-Lys-Cys-Leu-OH; SEQ ID NO.2: H-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Pro-Gln-OH; SEQ ID NO.3: H-Cys-Ser-Ile-Pro-Pro-Glu-Val-Lys-Pro-Phe-Val-Tyr-Leu-Ile-OH; SEQ ID NO.4: H-Arg-Arg-Arg-Arg-Arg-Arg-Arg-Arg-OH, SEQ ID NO.5: H-Arg-Arg-Arg-Arg-Arg-Arg-OH; SEQ ID NO.6: H-Arg-Arg-Arg-Arg-OH; SEQ ID NO.7: H-Leu-Leu-Ile-Ile-Leu-Arg-Arg-Arg-Ile-Arg-Lys-Gln-Ala-His-Ala-His-Ser-Lys-OH; SEQ ID NO.8: H-Tyr-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-OH; SEQ ID NO.9: H-Arg-Gln-Ile-Lys-Ile-Trp-Phe-Gln-Asn-Arg-Arg-Met-Lys-Trp-Lys-Lys-OH; SEQ ID NO.10: H-Val-Gln-Trp-Arg-Ile-Arg-Val-Ala-Val-Ile-Arg-Lys-OH; SEQ ID NO.11:H-Ser-Asp-Leu-Trp-Glu-Met-Met-Met-Val-Ser-Leu-Ala-Cys-Gln-Tyr-OH; SEQ ID NO.12:H-Lys-Leu-Ala-Leu-Lys-Leu-Ala-Leu-Lys-Ala-Leu-Lys-Ala-Ala-Leu-Lys-Leu-Ala-OH; SEQ ID NO.13:H-Pro-Phe-Val-Tyr-Leu-Ile-OH; SEQ ID NO.14:H-Gly-Pro-Hyp-Gly-Pro-Hyp-OH; SEQ ID NO.15:H-Gly-Pro-Hyp-OH; SEQ ID NO.16:H-Arg-Cys-Cys-Asn-Ser-Ser-Lys-Trp-Cys-Arg-Asp-His-Ser-Arg-Cys-Cys-NH2; SEQ ID NO.17:H-β-Ala-His-OH; SEQ ID NO.18:H-Glu-Glu-Met-Gln-Arg-Arg-NH2; SEQ ID NO.19:H-Gly-His-Lys-OH; SEQ ID NO.20:H-Met-Pro-D-Phe-Arg-D-Trp-Phe-Lys-Pro-Val-NH2; SEQ ID NO.21:H-Val-Trp-OH; SEQ ID NO.22:H-Gly-Gly-OH; SEQ ID NO.23:H-Ser-Thr-Pro-NH2; SEQ ID NO.24:H-Gly-Pro-Arg-Pro-Ala-NH2; SEQ ID NO.25:H-His-D-Trp-Ala-Trp-D-Phe-Lys-NH2; SEQ ID NO.26:H-Glu-Glu-Met-Gln-Arg-Arg-NH2; SEQ ID NO.27:H-Gly-Pro-Gln-Gly-Pro-Gln-OH; SEQ ID NO.28: H-Phe-Val-Ala-Pro-Phe-Pro-OH; SEQ ID NO.29: H-Lys-Asp-Val-Tyr-OH; SEQ ID NO.30: H-Lys-Gly-His-Lys-NH2; SEQ ID NO.31: H-β-Ala-His-Ser-His-OH; SEQ ID NO.32: H-Gln-Asp-Val-His-OH; SEQ ID NO.33: H-Pro-Pro-Tyr-Leu-OH; SEQ ID NO.34: H-His-Leu-Leu-Arg-OH; SEQ ID NO.35: H-Nle-Ala-His-D-Phe-Arg-Trp-NH2; SEQ ID NO.36: H-Ser-Val-Val-Val-Arg-Thr-OH; SEQ ID NO.37: H-Glu-Glu-Met-Gln-Arg-Arg-Ala-Asp-NH2; SEQ ID NO. 38: H-Tyr-Arg-OH.

[0010] Secondly, the present invention provides a method for preparing the aforementioned polypeptide coupling compound, the method comprising the following steps: Step 1: Synthesize compound (I) (1) Dissolve 2,4-dihydroxyacetophenone in acetone, add copper bromide, stir and reflux for 1-6 hours, let it return to room temperature, filter, and retain the filtrate; (2) Add thiourea to the filtrate from step (1), heat under reflux for 1-4 hours, filter to obtain a solid, dissolve the solid in sodium bicarbonate solution, stir for 30 minutes, filter again, and retain the filter cake. (3) Dissolve the filter cake from step (2) in DMF, add succinic anhydride and DMAP, react at room temperature for 24-48 hours, add sodium hydroxide aqueous solution to the reaction solution and stir for 1 hour, adjust the pH of the reaction solution to 2 with 6 mol / L hydrochloric acid, and obtain compound (I) after extraction with ethyl acetate, organic phase concentration and silica gel column chromatography purification. Step 2: Synthesize the target polypeptide conjugate (II) The polypeptide described in any of SEQ ID NO. 1 to 38 was synthesized using the Fmoc solid-phase polypeptide synthesis method. The compound (I) prepared in the first step was directly coupled on a solid-phase support. After coupling, a lysis buffer was added and the mixture was lysed to obtain a crude product. The crude product was purified by HPLC to obtain a pure polypeptide-coupled compound (II).

[0011] Furthermore, in step (1) of the first step, the molar ratio of 2,4-dihydroxyacetophenone to copper bromide is 1:2.

[0012] Furthermore, in step (2) of the first step, the molar ratio of thiourea to 2,4-dihydroxyacetophenone is 1:1.

[0013] Furthermore, in step (3) of the first step, the molar ratio of the succinic anhydride to the filter cake obtained in step (2) is 3:1.

[0014] Furthermore, in the second step, the Fmoc solid-phase polypeptide synthesis method uses Wang Resin as the solid-phase support, the deprotection reagent is a 20% piperidine DMF solution, and the coupling reagent is a combination of 1-hydroxybenzotriazole (HOBt) and N,N'-diisopropylcarbodiimide (DIC).

[0015] Furthermore, in the second step, the coupling reaction temperature is 60-70℃; the volume ratio of the pyrolysis solution is TFA:TIS:EDT:PhOH:H2O=90:3:3:2:2, and the pyrolysis reaction is carried out at room temperature for 2.5 hours.

[0016] Furthermore, the amount of the lysis buffer used is 10 mL per gram of peptide resin.

[0017] Thirdly, the present invention provides the use of the above-mentioned polypeptide coupling compound in the preparation of whitening cosmetics.

[0018] Furthermore, the cosmetics include serums, lotions, creams, or masks; the whitening cosmetics also have anti-wrinkle and anti-aging effects.

[0019] Thirdly, the present invention provides a whitening cosmetic containing the above-mentioned polypeptide conjugate compound in a content of 0.1%-5% by mass.

[0020] Compared with the prior art, the present invention has the following beneficial effects: (1) The polypeptide-coupled compound provided by the present invention, by coupling a 4-butylresorcinol analog to a polypeptide sequence, not only significantly improves the water solubility of the 4-butylresorcinol analog, solving its poor solubility in aqueous phase. On this basis, further coupling with polypeptides with multiple functions will not only effectively enhance the whitening activity of the 4-butylresorcinol analog, but also exert the skin-beautifying effect of the polypeptide itself, achieving the goal of one molecule having multiple functions.

[0021] (2) The polypeptide sequence selected in this invention not only has certain skin-use efficacy but also has tyrosinase targeting activity, which can significantly enhance the cell penetration and skin permeability of 4-butylresorcinol analogs, promoting their effective delivery in the skin. In addition, the polypeptide used in this invention has good safety and biocompatibility, providing a more efficient and safer option for skin care.

[0022] (3) The polypeptide coupling compound provided by the present invention has a simple structure, mild reaction conditions, is easy to prepare, has a high synthesis success rate, and the product has high purity. Its application in whitening cosmetics has good market prospects. Detailed Implementation

[0023] The following embodiments are merely some, not all, of the embodiments of the present invention. Therefore, the detailed descriptions of the embodiments provided below are not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] In this invention, unless otherwise specified, all equipment and raw materials are commercially available or commonly used in the industry. The methods described in the following embodiments are conventional methods in the art, unless otherwise specified.

[0025] Example 1 Synthesis of compound (I) (1) 2,4-Dihydroxyacetophenone (305 g, 2 mol) was dissolved in 4 L of acetone, and copper bromide (898 g, 4 mol, 2.0 eq) was added. After stirring and refluxing for 2 hours, the mixture was allowed to return to room temperature, filtered, and the filtrate was retained for the next step of the reaction.

[0026] (2) Add thiourea (152 g, 2 mol) to the solution from the above reaction, and heat under reflux at 60-70 °C for 2 hours. A large amount of solid is generated. After filtration, the solid is dissolved in sodium bicarbonate solution. After stirring for 30 minutes, filter and retain the filter cake (374 g, yield about 90%) for the next step of the reaction.

[0027] (3) The solid obtained in the previous step (374 g, 1.8 mol) was dissolved in 2 LDM, and succinic anhydride (540 g, 5.4 mol, 3.0 eq) and 2 g of DMAP were added. The reaction was carried out at room temperature for 24-48 hours, and sodium hydroxide aqueous solution was added to the reaction solution and stirred for 1 hour. The pH of the reaction solution was adjusted to 2 with 6N hydrochloric acid. Then, the solution was extracted with ethyl acetate, the organic phase was concentrated, purified by silica gel column chromatography, and dried to obtain 388 g of compound (I).

[0028] Example 2 Synthesis of peptide resin with polypeptide sequence SEQ ID NO.1 The standard method for solid-phase synthesis of Fmoc peptides was adopted. Based on the selected peptide sequence SEQ ID NO.1: AGYLLGKINLKACAALAKKCL, 10 g of Wang Resin with a substitution degree of 1.0 mmol / g was weighed and added to the solid-phase reaction column. DMF was added, and the mixture was allowed to swell for 5 minutes. 3.6 g (10 mmol) of Fmoc-Leu-OH, 1.6 g (12 mmol) of HOBt, and 0.1 g (1 mmol) of DMAP were weighed, dissolved in DMF, and 2 ml (12 mmol) of DIC was added. The mixture was then added to the reaction column, and after reacting for 20 minutes, 7 ml of acetic anhydride and 6 ml of pyridine were added. The mixture was mixed and blocked for 30 minutes. The mixture was washed three times with DCM, condensed with methanol, and the resin was dried under vacuum to obtain a total of 12.2 g of Fmoc-Leu-Wang Resin. The substitution degree was detected to be 0.324 mmol / g, totaling approximately 4 mmol.

[0029] The obtained Fmoc-Leu-Wang resin was washed three times with DMF, and then swollen with DMF for 10 minutes. The Fmoc protecting group was then removed with a 20% piperidine DMF solution for 5 minutes, followed by washing with DMF five times. 7 g (12 mmol) of Fmoc-Cys(Trt)-OH and 1.5 g (12 mmol) of HOBt were weighed, dissolved in DMF, and 2.5 ml (15 mmol) of DIC was added under an ice-water bath at 0°C. The mixture was activated for 5 minutes, added to the reaction column, and reacted for 120 minutes. The Fmoc protecting group was then removed with a 20% piperidine DMF solution for 5 minutes, completing the coupling of the Cys residues. Repeat the above steps, sequentially coupling Fmoc-Lys(Boc)-OH, Fmoc-Lys(Boc)-OH, Fmoc-Ala-OH, Fmoc-Leu-OH, Fmoc-Ala-OH, Fmoc-Ala-OH, Fmoc-Cys(Trt)-OH, Fmoc-Ala-OH, Fmoc-Lys(Boc)-OH, Fmoc-Leu-OH, Fmoc-Asn(Trt)-OH, Fmoc-Ile-OH, Fmoc-Lys(Boc)-OH, Fmoc-Gly-OH, Fmoc-Leu-OH, Fmoc-Tyr(tBu)-OH, Fmoc-Gly-OH, and Fmoc-Ala-OH according to the peptide sequence. After the reaction is complete, wash the peptide resin with DMF.

[0030] Example 3 Synthesis of the target compound (I) binding to the polypeptide sequence SEQ ID NO.1 Weigh 3.7 g (12 mmol) of compound (I) prepared in Example 1 and 1.5 g (12 mmol) of HOBt, dissolve in DMF, add 2.5 ml of DIC (15 mmol) in an ice-water bath at 0 °C, activate for 5 minutes, add to the peptide resin reaction column prepared in Example 2, and couple for 120 minutes. After the reaction, wash the resin 6 times with DMF, wash 3 times with DCM, then wash with methanol for 3 × 10 minutes, and dry under vacuum to obtain 20.6 g of peptide resin of the target compound of SEQ ID NO.1.

[0031] The above peptide resin was added to a 200 ml single-necked flask. A lysis buffer of 120 ml (TFA:TIS:EDT:PhOH:H2O = 90:3:3:2:2, volume ratio) was prepared beforehand. The lysis buffer was added to the flask, and the mixture was reacted at room temperature for 2.5 hours. The resin was filtered off, washed with 5 ml of TFA, and the filtrates were combined. The filtrates were added to 1200 ml of anhydrous diethyl ether, precipitating a white solid. The solid was centrifuged, washed with anhydrous diethyl ether, and dried under vacuum to obtain 10.4 g of crude white solid. The crude product was purified by HPLC to obtain 6.8 g of the target molecule with a purity of 99.32%.

[0032] Example 4 Synthesis of the target compound of other polypeptide sequence-binding compound (I) The same target compound can be obtained by using the same method as in Examples 2 and 3. Specific synthesis data are shown in the table below.

[0033] Table 1. Number of samples obtained from the synthesis of peptide-coupled compounds

[0034] Example 5: Compound Toxicity Detection (1) Cell culture Human epidermal melanocytes (HEMs) were cultured in DMEM medium containing 1% penicillin / streptomycin and 10% fetal bovine serum. The cell culture incubator conditions were set to 37°C and 5% CO2.

[0035] (2) Cytotoxicity test HEM cells were cultured in 96-well plates at a rate of 6 × 10⁶ cells per well. 4 After seeding individual cells and culturing for 24 h to allow cell adhesion, the culture medium was aspirated, and each well was replenished with culture medium containing different concentrations (100, 200, 400, 800 mg / L) of peptide compounds. The blank control group was treated with culture medium without peptide conjugates. Cells were incubated at 37°C for 24 h. The original culture medium was then aspirated, and 100 μL of 10% CCK solution was added to each well. After incubating in solution 8 for 1 h, the absorbance was measured at 450 nm, and the HEM cell viability was calculated. The results are shown in the table below.

[0036] Table 2. Cell viability test results of peptide-conjugated compounds

[0037] As can be seen from the data in Table 2, all concentrations of the peptide-conjugated compound had no significant effect on the cell viability of HEM cells, indicating that the compound was non-cytotoxic and had high safety.

[0038] Example 6: Solubility test of peptide-coupled compounds Accurately weigh 1-100 mg of the polypeptide conjugate, compound (I), and peptide amantadine. Add the weighed compounds to different EP tubes and add 1 mL of water. Mix the solutions at room temperature using a vortex mixer for 5 min, observe the dissolution, and record whether the compounds are completely dissolved. The results are shown in Table 3.

[0039] Table 3 Solubility test of peptide-coupled compounds

[0040] As shown in Table 3, the solubility of Peptide Amide in water is essentially zero. Compound (I) shows some improvement in solubility compared to Peptide Amide, but its solubility is still only 0.5 g / L. The solubility of the coupling compounds in this invention all exceed 30 g / L, representing a significant improvement compared to compound (I). This demonstrates that peptide coupling effectively improves the water solubility of resorcinol derivatives. Example 7 Skin permeability test of peptide-conjugated compounds Five peptide-conjugated compounds and compound (I) were randomly selected for a comparative study on skin permeability.

[0041] Ten healthy adult male mice were selected and their hair was removed with 10% Na2S. The animals were sacrificed 48 hours later, and undamaged skin grafts from their abdomens were randomly assembled into skin infiltration chambers. The grafts were placed 5.4 cm from the upper chamber. 2 200 μL of aqueous solutions of polypeptide-conjugated compounds (SEQ ID NO.1), (SEQ ID NO.6), (SEQ ID NO.12), (SEQ ID NO.28), (SEQ ID NO.32), and compound (I) were respectively applied to the skin surface. The weight of each polypeptide-conjugated compound (SEQ ID NO.1), (SEQ ID NO.6), (SEQ ID NO.12), (SEQ ID NO.28), and (SEQ ID NO.32) was 100 mg, and compound (I) was its saturated solution. The application dose was 18.51 mg / cm². 2 10 ml of double-distilled water was injected indoors as the receiving solution. The receiving solution was collected at 1, 2, 4, 6, 12, and 24 hours, with four parallel samples at each time point. High-performance liquid chromatography (HPLC) was used for identification, and permeability (P), permeate volume (T), and permeation rate (V) were calculated. The final results are shown in Table 1. Osmotic T (mg / cm) 2 = Total sample volume W (mg) in the receiving solution / Area of ​​drug application (cm²) 2); Permeability P (%) = Total sample volume W (mg) in the receiving solution / Total amount of drug applied (mg) * 100%.

[0042] The results showed that the peptide-conjugated compound had better skin permeability than compound (I), and the permeability and permeation area continued to increase over time.

[0043] Table 4. Skin permeability test in mice

[0044] Example 8: In vitro skin whitening efficacy test of peptide-conjugated compounds Eight peptide-coupled compounds, compound (I), and peptide-anmido were randomly selected for comparative whitening efficacy tests.

[0045] Using PBS as a solvent, a 1 mg / mL solution of the substrate L-DOPA was prepared, and a 100 U / mL enzyme solution of tyrosinase was prepared. The experiment consisted of a reaction group, a reaction control group, a blank group, and a blank control group. 25 μL of 100 ppm peptidoside (dissolved in ethanol), compound (I), and peptide-coupled compound sample were added to the reaction group and reaction control group, respectively. An equal volume of PBS was added to the blank group and blank control group. Then, 25 μL of the prepared tyrosinase solution was added to the reaction group and blank group, while an equal volume of PBS was added to the reaction control group and blank control group. All mixtures were thoroughly mixed and incubated at 37°C for 5 min. 100 μL of the prepared L-DOPA solution was added to all experimental groups, and incubation was continued at 37°C for 5 min. The absorbance (A) was measured at 475 nm. The experiment was repeated three times, and the tyrosinase inhibition rate was calculated using the following formula: Inhibition rate = 1 - (Reaction group - Reaction control group) / (Blank group - Blank control group) x 100% The results are shown in Table 5. After conjugation with peptides, the peptide-conjugated compounds all showed higher inhibition rates against tyrosinase than peptide Amidato and compound (I).

[0046] Table 5. Inhibition rate of peptide-conjugated compounds on tyrosinase

[0047] Example 9: In vitro anti-wrinkle efficacy test of peptide-conjugated compounds Eight peptide-coupled compounds, the same as those in Example 8, as well as compound (I) and peptide amido, were selected for comparative anti-wrinkle efficacy tests.

[0048] 200 μL of 0.12 mol Tris-Cl buffer (pH 8.0) was mixed with N-succinyl-tris-L-alanine 4-nitrobenzenetan to bring the concentration to 1.0 mmol. 30 μL of the 100 ppm coupling compound, a blank control sample, and 20 μL of 2.5 U / mL porcine pancreatic elastase were mixed with the solution. After incubation at 25°C for 20 min, the absorbance at 410 nm was measured using a microplate reader to determine the effect of the sample on elastase activity. The calculation formula is as follows: Elastase inhibition rate = 1 - (Experimental group - Blank group) / (Control - Blank) x 100% Table 6. Inhibition rate of peptide-conjugated compounds on elastase

[0049] The results are shown in Table 6. Compared with Peptide Amide and Compound (I), the polypeptide conjugate in this invention has a significantly greater inhibitory effect on elastase and exhibits good anti-wrinkle and anti-aging effects. This also demonstrates that the polypeptide conjugate has both whitening and anti-wrinkle and anti-aging effects.

[0050] Example 10 Application of peptide-coupled compounds in the preparation of serums Eight peptide-coupled compounds and compound (I), the same as those in Example 8, were selected and formulated into corresponding serums for comparative efficacy testing.

[0051] Prepare the serum according to the addition amounts and processes shown in the table below. In this example, the percentages are the mass percentages of each component in the final serum.

[0052] Table 7 Whitening Essence Formula Table

[0053] Table 8-9 presents the performance analysis results of the above-mentioned serums.

[0054] Table 8. Human Efficacy Test for Spot Removal and Skin Whitening (Area of ​​Spots in mm) 2 )

[0055] Table 9. Anti-wrinkle efficacy test on human body (total wrinkle area in mm) 2 )

[0056] As can be seen from Tables 8-9, compound (I) has a significant whitening effect, but its anti-wrinkle effect is only moderate. However, after compound (I) is conjugated with related peptides, it not only has a significant whitening effect but also an anti-aging effect.

[0057] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A polypeptide conjugate compound, characterized in that, The structure of the polypeptide conjugate is shown in formula (II): (II) In formula (II), Peptide is any polypeptide sequence shown in SEQ ID NO.1~38, and the amino group of the N-terminal amino acid of the polypeptide sequence is connected to the carboxyl group of compound (I) through an amide bond to obtain compound (II). The structure of compound (I) is shown in (I) below: （I）。 2. The polypeptide coupling compound according to claim 1, characterized in that, The polypeptide sequences shown in SEQ ID NO. 1~38 are respectively: SEQ ID NO.1: H-Ala-Gly-Tyr-Leu-Leu-Gly-Lys-Ile-Asn-Leu-Lys-Ala-Cys-Ala-Ala-Leu-Ala-Lys-Lys-Cys-Leu-OH; SEQ ID NO.2: H-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Pro-Gln-OH; SEQ ID NO.3: H-Cys-Ser-Ile-Pro-Pro-Glu-Val-Lys-Pro-Phe-Val-Tyr-Leu-Ile-OH; SEQ ID NO.4: H-Arg-Arg-Arg-Arg-Arg-Arg-Arg-Arg-OH, SEQ ID NO.5: H-Arg-Arg-Arg-Arg-Arg-Arg-OH; SEQ ID NO.6: H-Arg-Arg-Arg-Arg-OH; SEQ ID NO.7: H-Leu-Leu-Ile-Ile-Leu-Arg-Arg-Arg-Ile-Arg-Lys-Gln-Ala-His-Ala-His-Ser-Lys-OH; SEQ ID NO.8: H-Tyr-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-OH; SEQ ID NO.9: H-Arg-Gln-Ile-Lys-Ile-Trp-Phe-Gln-Asn-Arg-Arg-Met-Lys-Trp-Lys-Lys-OH; SEQ ID NO.10: H-Val-Gln-Trp-Arg-Ile-Arg-Val-Ala-Val-Ile-Arg-Lys-OH; SEQ ID NO.11: H-Ser-Asp-Leu-Trp-Glu-Met-Met-Met-Val-Ser-Leu-Ala-Cys-Gln-Tyr-OH; SEQ ID NO. 12: H-Lys-Leu-Ala-Leu-Lys-Leu-Ala-Leu-Lys-Ala-Leu-Lys-Ala-Ala-Leu-Lys-Leu-Ala-OH; SEQ ID NO.13:H-Pro-Phe-Val-Tyr-Leu-Ile-OH; SEQ ID NO.14:H-Gly-Pro-Hyp-Gly-Pro-Hyp-OH; SEQ ID NO.15:H-Gly-Pro-Hyp-OH; SEQ ID NO.16:H-Arg-Cys-Cys-Asn-Ser-Ser-Lys-Trp-Cys-Arg-Asp-His-Ser-Arg-Cys-Cys-NH2; SEQ ID NO.17:H-β-Ala-His-OH; SEQ ID NO.18:H-Glu-Glu-Met-Gln-Arg-Arg-OH; SEQ ID NO.19:H-Gly-His-Lys-OH; SEQ ID NO.20:H-Met-Pro-D-Phe-Arg-D-Trp-Phe-Lys-Pro-Val-NH2; SEQ ID NO.21:H-Val-Trp-OH; SEQ ID NO.22:H-Gly-Gly-OH; SEQ ID NO.23:H-Ser-Thr-Pro-NH2; SEQ ID NO.24:H-Gly-Pro-Arg-Pro-Ala-NH2; SEQ ID NO.25:H-His-D-Trp-Ala-Trp-D-Phe-Lys-NH2; SEQ ID NO.26:H-Glu-Glu-Met-Gln-Arg-Arg-NH2; SEQ ID NO.27:H-Gly-Pro-Gln-Gly-Pro-Gln-OH; SEQ ID NO.28:H-Phe-Val-Ala-Pro-Phe-Pro-OH; SEQ ID NO.29:H-Lys-Asp-Val-Tyr-OH; SEQ ID NO.30:H-Lys-Gly-His-Lys-NH2; SEQ ID NO.31:H-β-Ala-His-Ser-His-OH; SEQ ID NO.32:H-Gln-Asp-Val-His-OH; SEQ ID NO.33:H-Pro-Pro-Tyr-Leu-OH; SEQ ID NO.34:H-His-Leu-Leu-Arg-OH; SEQ ID NO.35:H-Nle-Ala-His-D-Phe-Arg-Trp-NH2; SEQ ID NO.36:H-Ser-Val-Val-Val-Arg-Thr-OH; SEQ ID NO.37:H-Glu-Glu-Met-Gln-Arg-Arg-Ala-Asp-NH2; SEQ ID NO. 38: H-Tyr-Arg-OH.

3. A method for preparing the polypeptide coupling compound according to claim 1 or 2, characterized in that, The preparation method includes the following steps: Step 1: Synthesize compound (I) (1) Dissolve 2,4-dihydroxyacetophenone in acetone, add copper bromide, stir and reflux for 1-6 hours, let it return to room temperature, filter, and retain the filtrate; (2) Add thiourea to the filtrate from step (1), heat under reflux for 1-4 hours, filter to obtain a solid, dissolve the solid in sodium bicarbonate solution, stir for 30 minutes, filter again, and retain the filter cake. (3) Dissolve the filter cake from step (2) in DMF, add succinic anhydride and DMAP, react at room temperature for 24-48 hours, add sodium hydroxide aqueous solution to the reaction solution and stir for 1 hour, adjust the pH of the reaction solution to 2 with 6 mol / L hydrochloric acid, and obtain compound (I) after extraction with ethyl acetate, organic phase concentration and silica gel column chromatography purification. Step 2: Synthesize the target polypeptide conjugate (II) The polypeptide described in any of SEQ ID NO. 1 to 38 was synthesized using the Fmoc solid-phase polypeptide synthesis method. The compound (I) prepared in the first step was directly coupled on a solid-phase support. After coupling, a lysis buffer was added and the mixture was lysed to obtain a crude product. The crude product was purified by HPLC to obtain a pure polypeptide-coupled compound (II).

4. The method for preparing the polypeptide coupling compound according to claim 3, characterized in that, In step (1) of the first step, the molar ratio of 2,4-dihydroxyacetophenone to copper bromide is 1:2, and 2,4-dihydroxyacetophenone is dissolved in acetone at a molar volume ratio of 1:2 (mol / L); in step (2) of the first step, the molar ratio of thiourea added to 2,4-dihydroxyacetophenone is 1:

1.

5. The method for preparing the polypeptide coupling compound according to claim 3, characterized in that, In step (3) of the first step, the molar ratio of the succinic anhydride to the filter cake obtained in step (2) is 3:

1.

6. The method for preparing the polypeptide coupling compound according to claim 3, characterized in that, In the second step, the Fmoc solid-phase polypeptide synthesis method uses Wang Resin as the solid-phase support, a 20% piperidine DMF solution as the deprotection agent, and a combination of 1-hydroxybenzotriazole (HOBt) and N,N'-diisopropylcarbodiimide (DIC) as the coupling agent.

7. The method for preparing the polypeptide coupling compound according to claim 3, characterized in that, In the second step, the volume ratio of the lysis buffer is TFA:TIS:EDT:PhOH:H2O=90:3:3:2:2, and the lysis reaction is carried out at room temperature for 2.5 hours; the amount of the lysis buffer used is 10 mL per gram of peptide resin.

8. Use of the polypeptide conjugate of claim 1 or 2 in the preparation of skin-whitening cosmetics.

9. The application according to claim 8, characterized in that, The cosmetics include serums, lotions, creams, or masks; the whitening cosmetics also have anti-wrinkle and anti-aging effects.

10. A whitening cosmetic product, characterized in that, The product comprises the polypeptide conjugate of claim 1 or 2, wherein the mass percentage content is 0.1-5%.

Images