Preparation method and application of N-alkylamide natural product Cubebamide and analogue thereof

Abstract

The invention relates to a preparation method and application of an N-alkyl amide natural product Cubebamide and an analogue thereof, and belongs to the field of compound technologies and medicinal chemistry. According to the invention, commercially available 3, 4, 5-trimethoxybenzaldehyde 1 is used as a raw material, a compound 3 is obtained through a Horner-Wadsworth-Emmons (HWE) reaction, and then a compound 4 is obtained through hydrolysis. A compound 5a-5f is used as a raw material, a compound 6a-6f is synthesized through a Henry reaction, and a compound 8a-8f is obtained through double bond and nitro reduction. And carrying out condensation reaction on the two fragments 4 and 8a-8f to obtain the natural product Cubebamide and the analogue 9a-9f thereof. The compounds 9a, 9c and 9d disclosed by the invention have relatively good anti-inflammatory activity; the compounds 9b, 9e and 9f have remarkable anti-inflammatory activity. The synthesis method has the advantages of easily available raw materials, mild reaction conditions, environmental protection and simple operation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of compounds and medicinal chemistry, and particularly relates to a preparation method and application of a natural product Cubebamide and analogues thereof. BACKGROUND

[0002] N-alkyl amide compounds have structural diversity and wide pharmacological activities. Therefore, they have attracted wide attention of scientists in the pharmaceutical, cosmetic and food industries. The natural product Cubebamide is a novel N-alkyl amide compound extracted and separated from the homology of medicine and food plant Litsea cubeba. Researches show that Cubebamide can significantly inhibit the production of nitric oxide (NO) of LPS-induced mouse peritoneal macrophages, and the IC 50 is 18.45 μM, and Cubebamide has the potential to be developed into an anti-inflammatory lead compound. At present, the Cubebamide is mainly obtained by separation and purification from plants, and the operation is complicated and the source is limited, which greatly limits the research on the biological activity of Cubebamide. Chemical synthesis is one of the important ways to obtain natural products in large quantities. In view of the good anti-inflammatory activity of Cubebamide, and no related full synthesis research is reported at present, the present application designs a new preparation method of Cubebamide and analogues thereof, and some compounds obtained by the method show strong anti-inflammatory activity, and can be used as drugs or drug lead compounds. SUMMARY

[0003] The present application aims to provide a new preparation method and application of a natural product Cubebamide and analogues thereof, and the structural formula is shown as A.

[0004]

[0005] In the above chemical structural formula, R1 is selected from any one of atoms or groups of hydroxyl and methoxyl; R2 is selected from any one of atoms or groups of fluorine, chlorine, hydroxyl and methoxyl; and R3 is selected from any one of atoms or groups of hydrogen and methoxyl.

[0006] The present application provides a preparation method of the compound of formula A.

[0007]

[0008]

[0009] (1) 3,4,5-trimethoxybenzaldehyde 1 is used as a raw material, and a compound 3 is obtained by Horner-Wadsworth-Emmons (HWE) reaction.

[0010] (2) Compound 3 was dissolved in a mixture of THF and H2O, and LiOH.H2O was added at 0°C. The mixture was stirred at room temperature for 12 h. After acidification, extraction, drying, filtration, concentration and purification by flash column chromatography on silica gel, compound 4 was obtained.

[0011] (3) Compound 5a-5f was dissolved in MeNO2, and ethylenediamine was added at room temperature. The mixture was stirred at 100°C for 3 h. After cooling, filtration, washing and drying, compound 6a-6f was obtained.

[0012] (4) Compound 6a-6f was dissolved in a mixture of THF and EtOH, and NaBH4 was added at 0°C. The mixture was stirred at room temperature for 2 h. After extraction, drying, filtration, concentration and purification by flash column chromatography on silica gel, compound 7a-7f was obtained.

[0013] (5) Compound 7a-7f was dissolved in a mixture of MeOH and H2O, and NH4Cl and iron powder were added at 0°C. The mixture was stirred at 80°C for 1 h. After extraction, filtration, concentration and purification by flash column chromatography on silica gel, compound 8a-8f was obtained.

[0014] (6) The above two fragments 4 and 8a-8f were subjected to amidation reaction in an organic solvent by adding a base and a condensing agent. The target compounds 9a-9f were obtained after separation and purification.

[0015] Further, the condensing agent used was one or more of EDCI / HOBt, HATU, HBTU, BOP, PyBOP, TCFH / NMI, T3P, CDI and DCC; preferably HATU;

[0016] The base used was one or more of triethylamine (Et3N), diisopropylethylamine (DIPEA), 4-dimethylaminopyridine (DMAP), pyridine, sodium carbonate, potassium carbonate, cesium carbonate, sodium acetate, sodium bicarbonate, sodium phosphate and potassium phosphate; preferably Et3N and / or DIPEA;

[0017] Further, the organic solvent used was one or more of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), THF, dichloromethane (CH2Cl2), chloroform (CHCl3), acetonitrile (MeCN), dioxane and toluene; preferably DMF;

[0018] Further, the molar ratio of compound 4 to 8a-8f was 1:2-2:1, preferably 1.5:1-1:1.5, and more preferably 1:1.2;

[0019] Further, the amount of condensing agent used was 1.0-2.0 equiv, preferably 1.2 equiv;

[0020] Further, the amount of the base used is 1.0-2.0 equiv, and preferably 1.2 equiv;

[0021] Further, the reaction temperature is 0-50℃, and preferably 20-25℃;

[0022] Further, the reaction time is 2-12 hours, and preferably 12 hours.

[0023] Further, according to the preparation method described above, the present application provides the following compounds (9a-9f) with the following structures:

[0024]

[0025] The present application also provides the use of the compound of formula A as an anti-inflammatory active substance.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] The experimental results show that the N-alkyl amide compounds 9a, 9c and 9d obtained by the present application have good anti-inflammatory activity; and the compounds 9b, 9e and 9f have significant anti-inflammatory activity. DETAILED DESCRIPTION

[0028] Synthesis of compound 3: LiCl (520 mg, 12.23 mmol) was dissolved in 20 mL of THF solution, protected by nitrogen, and triethyl phosphonoacetate 2 (2.45 mL, 12.23 mmol) was added under stirring at room temperature. After 15 min, DBU (1.71 mL, 11.21 mmol) and 3,4,5-trimethoxybenzaldehyde 1 (2.0 g, 10.19 mmol) were slowly added, and the reaction was carried out at room temperature for 12 h. The reaction was quenched by adding H2O (10 mL) at 0℃, extracted with ethyl acetate, washed with saturated NaCl solution, dried over anhydrous Na2SO4, filtered, concentrated, and purified by flash silica gel column chromatography to obtain compound 3 (2.58 g, 95%). 1 H NMR (400 MHz, CDCl3) δ 7.57 (d, J = 16.0 Hz, 1H), 6.73 (s, 2H), 6.32 (d, J = 16.0 Hz, 1H), 4.24 (q, J = 8.0 Hz, 2H), 3.86 (s, 6H), 3.85 (s, 3H), 1.31 (t, J = 8.0 Hz, 3H)

[0029] Synthesis of compound 4: Compound 3 (2.13 g, 8.0 mmol) was dissolved in a mixture of THF (10 mL) and H2O (5 mL), stirred at 0 °C for 10 min, and LiOH-H2O (0.67 g, 16.0 mmol) was added slowly. The reaction was stirred at room temperature for 12 h. The reaction was quenched with 1 M dilute hydrochloric acid at 0 °C and acidified. The reaction was extracted with ethyl acetate, washed with saturated NaCl solution, dried over anhydrous Na2SO4, filtered, concentrated, and purified by flash silica gel column chromatography to give compound 4 (1.70 g, 89%). 1 H NMR (400 MHz, CDCl3) δ 7.70 (d, J = 16.0 Hz, 1H), 6.77 (s, 2H), 6.35 (d, J = 16.0 Hz, 1H), 3.892 (s, 6H), 3.886 (s, 3H), 2.11 (s, 2H)

[0030] Synthesis of compounds 6a-6f: Compound 5a-5f (40.00 mmol, 1.0 equiv) was dissolved in 30 mL of MeNO2 solution, protected by nitrogen, and ethylenediamine (0.4 mmol, 0.01 equiv) was added under stirring at room temperature. The reaction was heated to 100 °C for 3 h, cooled to 0 °C, and filtered. The precipitate was washed with a small amount of MeOH / H2O = 1:1, 20 mL) and dried to give compounds 6a-6f.

[0031] Compound 6a, yield 90%, 1 H NMR (400 MHz, DMSO-d6) δ 10.05 (s, 1H), 8.15 (d, J = 12.0 Hz, 1H), 8.02 (d, J = 12.0 Hz, 1H), 7.47 (d, J = 4.0 Hz, 1H), 7.29 (dd, J1= 8.0 Hz, J2= 2.0 Hz, 1H), 6.85 (d, J = 8.0 Hz, 1H), 3.82 (s, 3H) Compound 6b, yield 88%, 1 H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 12.0 Hz, 1H), 7.53 (d, J = 12.0 Hz, 1H), 7.17 (dd, J1= 8.0 Hz, J2= 2.0 Hz, 1H), 7.00 (d, J = 2.0 Hz, 1H), 6.91 (d, J = 8.0 Hz, 1H), 3.93 (s, 3H), 3.22 (s, 3H) Compound 6c, yield 87%, 1H NMR (400 MHz, CDCI3) δ 7.91 (d, J = 8.0 Hz, 1 H), 7.48 (d, J = 12.0 Hz, 1 H), 7.1 1 (d, J = 4.0 Hz, 1 H), 7.09 (dd, J1= 8.0 Hz, J1= 4.0 Hz, 1 H), 6.89 (d, J = 8.0 Hz, 1 H), 5.75 (br s, 1 H), 3.96 (s, 3 H) Compound 6d, yield 66%, 1 H NMR (400 MHz, CDCI3) δ 7.90 (d, J = 12.0 Hz, 1 H), 7.53 (d, J = 16.0 Hz, 1 H), 6.75 (s, 2 H), 3.88 (s, 3 H), 3.87 (s, 6 H)

[0032] Compound 6e, yield 79%, 1 H NMR (400 MHz, DMSO-d6) δ 1 1.06 (br, 1 H), 8.06 (dd, J1= 36.0 Hz, J2= 16.0 Hz, 2 H), 7.95 (s, 1 H), 7.65 (d, J = 8.0 Hz, 1 H), 7.02 (d, J = 8.0 Hz, 1 H)

[0033] Compound 6f, yield 82%, 1 H NMR (400 MHz, DMSO-d6) δ 10.86 (s, 1 H), 8.09 (d, J = 8.0 Hz, 1 H), 8.02 (d, J = 8.0 Hz, 1 H), 7.77 (dd, J1= 8.0 Hz, J2= 4.0 Hz, 1 H), 7.50 (dd, J1= 8.0 Hz, J2= 4.0 Hz, 1 H), 7.01 (t, J = 8.0 Hz, 1 H) Synthesis of compounds 7a-7f: Compound 6a-6f (123.19 mmol, 1.0 equiv) was dissolved in a mixture of THF (25 mL) and EtOH (65 mL), stirred at 0 °C for 10 min, NaBH4(51.33 mmol, 2.4 equiv) was added slowly, stirred at room temperature for 2 h. The reaction was quenched by 1 M dilute hydrochloric acid solution at 0 °C, extracted by ethyl acetate, washed by saturated NaCI solution, dried by anhydrous Na2S04, filtered, concentrated, purified by flash silica gel column chromatography to give compounds 7a-7f.

[0034] Compound 7a, yield 58%, 1 H NMR (400 MHz, CDCI3) δ 6.86 (d, J = 8.0 Hz, 1 H), 6.71 - 6.69 (m, 2 H), 5.62 (s, 1 H), 4.57 (t, J = 8.0 Hz, Hz, 2 H), 3.87 (s, 3 H), 3.24 (t, J = 8.0 Hz, 2 H)

[0035] Compound 7b, yield 65%,1H NMR (400 MHz, CDC13) δ 6.81 (d, J = 8.0 Hz, 1H), 6.74 (dd, Ji = 8.0 Hz, J2= 2.0 Hz, 1H), 6.70 (d, J = 1.6 Hz, 1H), 4.58 (t, J = 8.0 Hz, 2H), 3.86 (s, 3H), 3.85 (s, 3H), 3.26 (t, J = 8.0 Hz, 2H) 1 H NMR (400 MHz, CDC13) δ 6.80-6.77 (m, 2H), 6.67 (dd, Ji = 8.0 Hz, J2= 4.0 Hz, 1H), 5.68 (s, 1H), 4.56 (t, J = 8.0 Hz, 2H), 3.86 (s, 3H), 3.21 (t, J = 8.0 Hz, 2H)

[0036] Compound 7c, yield 60%,1H NMR (400 MHz, CDC13) δ 6.80-6.77 (m, 2H), 6.67 (dd, Ji = 8.0 Hz, J2= 4.0 Hz, 1H), 5.68 (s, 1H), 4.56 (t, J = 8.0 Hz, 2H), 3.86 (s, 3H), 3.21 (t, J = 8.0 Hz, 2H) 1 H NMR (400 MHz, CDC13) δ 6.40 (s, 2H), 4.60 (t, J = 8.0 Hz, 2H), 3.84 (s, 6H), 3.82 (s, 3H), 3.26 (t, J = 8.0 Hz, 2H)

[0037] Compound 7d, yield 55%,1H NMR (400 MHz, CDC13) δ 6.40 (s, 2H), 4.60 (t, J = 8.0 Hz, 2H), 3.84 (s, 6H), 3.82 (s, 3H), 3.26 (t, J = 8.0 Hz, 2H) 1 H NMR (400 MHz, CDC13) δ 7.17 (s, 1H), 7.01 (d, J = 12.0 Hz, 1H), 6.96 (d, J = 8.0 Hz, 1H), 5.63 (s, 1H), 4.57 (t, J = 8.0 Hz, 2H), 3.22 (t, J = 8.0 Hz, 2H)

[0038] Compound 7e, yield 63%,1H NMR (400 MHz, CDC13) δ 7.17 (s, 1H), 7.01 (d, J = 12.0 Hz, 1H), 6.96 (d, J = 8.0 Hz, 1H), 5.63 (s, 1H), 4.57 (t, J = 8.0 Hz, 2H), 3.22 (t, J = 8.0 Hz, 2H) 1 H NMR (400 MHz, CDC13) δ 6.95-6.91 (m, 2H), 6.87-6.85 (m, 1H), 5.60 (br s, 1H), 4.57 (t, J = 8.0 Hz, 2H), 3.22 (t, J = 8.0 Hz, 2H)

[0039] Compound 7f, yield 66%,1H NMR (400 MHz, CDC13) δ 6.95-6.91 (m, 2H), 6.87-6.85 (m, 1H), 5.60 (br s, 1H), 4.57 (t, J = 8.0 Hz, 2H), 3.22 (t, J = 8.0 Hz, 2H) 1 H NMR (400 MHz, CDC13) δ 6.95-6.91 (m, 2H), 6.87-6.85 (m, 1H), 5.60 (br s, 1H), 4.57 (t, J = 8.0 Hz, 2H), 3.22 (t, J = 8.0 Hz, 2H)

[0040] Synthesis of compound 8a-8f: Compound 7a-7f (13.60 mmol, 1.0 equiv) was dissolved in a mixture of MeOH (136 mL) and H2O (136 mL), stirred at 0 °C for 10 min, NH4Cl (136 mmol, 10.0 equiv), iron powder (67.96 mmol, 5.0 equiv) were added, stirred at 80 °C for 1 h. Filtration, concentration, the crude compound 8a-8f was used in the next step without purification.

[0041] 9a-9f: Compound 4 (3.36 mmol, 1.0 equiv) was dissolved in DMF (0.5 M) solution, protected by nitrogen, stirred at 0 °C for 10 min, Et3N (4.0 mmol, 1.2 equiv) and HATU (4.03 mmol, 1.2 equiv) were added, stirred for 30 min, 8a-8f (4.03 mmol, 1.2 equiv) was added, stirred at room temperature for 12 h. The reaction was quenched by the addition of H2O at room temperature, extracted with ethyl acetate, washed with saturated NaCl solution, dried over anhydrous Na2SO4, concentrated, purified by flash silica gel column chromatography to give compound 9a-9f.

[0042] Compound 9a, yield 75%, 1 H NMR (400 MHz, CD3OD) δ 7.44 (d, J = 16.0 Hz, 1H), 6.86 (s, 2H), 6.82 (d, J = 2.0 Hz, 1H), 6.72 (d, J = 8.0 Hz, 1H), 6.68 (dd, Ji = 8.0 Hz, J2= 2.0 Hz, 1H), 6.51 (d, J = 16.0 Hz, 1H), 3.86 (s, 6H), 3.83 (s, 3H), 3.78 (s, 3H), 3.50 (t, J = 8.0 Hz, 2H), 2.78 (t, J = 8.0 Hz, 2H)

[0043] Compound 9b, yield 72%, 1 H NMR (400 MHz, CD3OD) δ 7.51 (d, J = 8.0 Hz, 1H), 6.80 (d, J = 8.0 Hz, 1H), 6.74 (d, J = 8.0 Hz, 2H), 6.69 (s, 2H), 6.25 (d, J = 12.0 Hz, 1H), 5.76 (t, J = 4.0 Hz, 1H), 3.85 (s, 15H), 3.63 (q, J = 8.0 Hz, 2H), 2.82 (t, J = 8.0 Hz, 2H)

[0044] Compound 9c, yield 69%, 1H NMR (400 MHz, DMSO-d6) δ 8.84 (s, 1H), 8.05 (t, J = 8.0 Hz, 1H), 7.36 (d, J = 16.0 Hz, 1H), 6.88 (s, 1H), 6.82 (d, J = 8.0 Hz, 1H), 6.66 (d, J = 1.6 Hz, 1H), 6.61 - 6.55 (m, 2H), 3.81 (s, 6H), 3.72 (s, 3H), 3.68 (s, 3H), 3.35 (q, J = 8.0 Hz, 2H), 2.63 (t, J = 8.0 Hz, 2H)

[0045] Compound 9d, yield 66%, 1 H NMR (400 MHz, CDCl3) δ 7.52 (d, J = 16.0 Hz, 1H), 6.70 (s, 2H), 6.42 (s, 2H), 6.26 (d, J = 8.0 Hz, 1H), 3.85 (s, 9H), 3.83 (s, 6H), 3.82 (s, 3H), 3.64 (t, J = 8.0 Hz, 2H), 3.82 (t, J = 8.0 Hz, 2H)

[0046] Compound 9e, yield 65%, 1 H NMR (400 MHz, DMSO-d6) δ 9.93 (s, 1H), 8.06 (t, J = 8.0 Hz, 1H), 7.36 (d, J = 16.0 Hz, 1H), 7.19 (d, J = 2.0 Hz, 1H), 6.99 (dd, J1= 8.0 Hz, J1= 2.0 Hz, 1H), 6.89 (d, J = 8.0 Hz, 3H), 6.57 (d, J = 16.0 Hz, 1H), 3.81 (s, 6H), 3.68 (s, 3H), 3.38 (q, J = 8.0 Hz, 2H), 2.67 (t, J = 8.0 Hz, 2H)

[0047] Compound 9f, yield 70%, 1 H NMR (400 MHz, DMSO-d6) δ 9.59 (s, 1H), 8.06 (t, J = 8.0 Hz, 1H), 7.36 (d, J = 16.0 Hz, 1H), 7.02 - 6.99 (m, 1H), 6.88 (s, 2H), 6.86 - 6.82 (m, 2H), 6.57 (d, J = 16.0 Hz, 1H), 3.81 (s, 6H), 3.68 (s, 3H), 3.38 (t, J = 8.0 Hz, 2H), 2.67 (t, J = 8.0 Hz, 2H)

[0048] Test Example 1. Anti-inflammatory activity study

[0049] Methods: NO is widely distributed in the body, as a cell and intracellular information material, play a signaling role, is a new type of biological messenger molecules, play an important role in the body's physiology, pathology. Because of the NO itself is extremely unstable, in the cell is quickly metabolized to nitrate and nitrite, using nitrate reductase reduction of nitrate to nitrite, and then with the improved Griess Reagent reaction in 530 nm has a characteristic absorption peak of colored material, by measuring the change in its absorbance can be calculated in the sample of NO content.

[0050] Specific experimental steps as follows:

[0051] 1. First collect bacteria or cells into the centrifuge tube, centrifugation after the supernatant; take 50 million bacteria or cells added 0.5 mL extraction solution; ultrasonic bacteria or cell (ice bath, power 20% or 200 W, ultrasonic 3 s, interval 10 s, repeat 30 times); 4 ℃ x 12000 rpm, centrifugation 10 min, take the supernatant, on ice for testing.

[0052] 2. enzyme-linked instrument preheating 30 min above, adjust the wavelength to 530 nm. The rest of the reagent at 37 ℃ preheating 5 min. In 96 well plate in turn added.

[0053] 3. Nω- monomethyl-L-arginine (LNMMA) for positive control.

[0054] 4. Use enzyme-linked instrument at 530 nm wavelength measurement absorbance value.

[0055] 5. NO content (nmoL / 10 4 cell) = (V standard x V1) x △A ÷ (A standard-A blank) ÷ (V1 ÷ V x 50) x D x 10 3

[0056] = 0.2 x △A ÷ (A standard-A blank) x D

[0057] C standard - 0.1 μmoL / mL; V - the volume of the added extraction solution, 0.5 mL;

[0058] V1 - sample volume in the reaction, 0.06 mL; 50 - the number of cells, million;

[0059] D - dilution factor, not diluted is 1.

[0060] 6. NO production inhibition rate (%) = (LPS group ΔOD530 average - blank group ΔOD530 average) - (drug treatment group ΔOD530 average) - blank group ΔOD530 average / (LPS group ΔOD530 average - blank group ΔOD530 average) x 100%

[0061]

[0062] The results show that compounds 9a, 9c and 9d have good anti-inflammatory activity, and the NO production inhibition rates are 50.45%, 59.92% and 69.39%, respectively; compounds 9b, 9e and 9f have significant anti-inflammatory activity, and the NO production inhibition rates are 77.17%, 77.30% and 80.67%, respectively.

[0063] The foregoing description shows and describes several preferred embodiments of the invention, but it is understood that the invention is not limited to the forms disclosed, but is capable of carrying out various other combinations, modifications and environments, and can be modified and changed within the scope of the inventive concept described herein by the above teachings or related technical or knowledge, and the modifications and changes made by those skilled in the art without departing from the spirit and scope of the invention shall be within the protection scope of the claims of the invention.

Claims

1. A method for the preparation and use of N-alkyl amide natural product Cubebamide and its analogues, characterized by, The compound has the following structural formula: In the above chemical structural formula: R1 is selected from any one of the following atoms or groups: hydroxyl, methoxyl; R2 is selected from any one of the following atoms or groups: fluorine, chlorine, hydroxyl, methoxyl; R3 is selected from any one of the following atoms or groups: hydrogen, methoxyl.

2. The N-alkyl amide natural product Cubebamide and analogs thereof according to claim 1, characterized in that, The compound is selected from one of the following structural formulas:

3. Process for the preparation of a compound according to claim 1 or 2, characterized in that, The method comprises the following steps: (1) 3,4,5-trimethoxybenzaldehyde 1 is used as a raw material to obtain compound 3 through Horner-Wadsworth-Emmons (HWE) reaction. (2) Compound 3 was dissolved in a mixture of tetrahydrofuran (THF) and H2O, and LiOH was added at 0 °C . H2O, stirred at room temperature for 12 h. Acidification, extraction, drying, filtration, concentration, and purification by flash silica gel column chromatography gave compound 4. (3) Compound 5a-5f is dissolved in nitromethane (MeNO2) solution, ethylenediamine is added under stirring at room temperature, and the temperature is raised to 100°C for reaction for 3h. After cooling, filtration, washing, and drying, compound 6a-6f is obtained. (4) Compound 6a-6f is dissolved in a mixed solution of THF and EtOH, NaBH4 is added at 0°C, and stirring is carried out at room temperature for 2h. After extraction, drying, filtration, concentration, and fast silica gel column chromatography, compound 7a-7f is obtained. (5) Compound 7a-7f is dissolved in a mixed solution of MeOH and H2O, NH4Cl and iron powder are added at 0°C, and stirring is carried out at 80°C for 1h. After extraction, filtration, concentration, and fast silica gel column chromatography, compound 8a-8f is obtained. (6) The above two fragments 4 and 8a-8f are subjected to amidation reaction in an organic solvent by adding a base and a condensing agent, and the target compound 9a-9f is obtained after separation and purification.

4. The method of claim 3, wherein the step of preparing the mixture is performed by: The condensing agent used is one or more of EDCI / HOBt, HATU, HBTU, BOP, PyBOP, TCFH / NMI, T3P, CDI, and DCC; the base used is one or more of triethylamine (Et3N), diisopropylethylamine (DIPEA), 4-dimethylaminopyridine (DMAP), pyridine, sodium carbonate, potassium carbonate, cesium carbonate, sodium acetate, sodium bicarbonate, sodium phosphate, and potassium phosphate; and the organic solvent used is one or more of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), THF, dichloromethane (CH2Cl2), chloroform (CHCl3), acetonitrile (MeCN), dioxane, and toluene.

5. The method of claim 3, wherein the step of preparing the mixture is performed by mixing the first and second components in a ratio of 1 : 1 to 1 :

3. The molar ratio of compound 4 and 8a-8f is 1:2-2:1; the amount of condensing agent used is 1.0-2.0 equiv; and the amount of base used is 1.0-2.0 equiv.

6. The method of claim 3, wherein the step of preparing the mixture is performed by mixing the first and second components in a ratio of 1 : 1 to 1 :

3. The reaction temperature is 0-55°C.

7. The method of claim 3, wherein the step of preparing the mixture is characterized by, The reaction time is 2-12 hours.

8. Use of the compound according to claim 1 and / or 2 as an anti-inflammatory substance.

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