An alkylamide nuciferine derivative with both uric acid-lowering and kidney-protecting activities, and its preparation method and application

Abstract

The present invention belongs to the field of drug synthesis, and specifically relates to an alkylamide nuciferine derivative having both uric acid-lowering and kidney-protecting activities, and its preparation method and application. The present invention structurally modifies nuciferine by introducing active groups, thereby improving the biological activity of nuciferine in lowering uric acid. Cell experiments have found that the alkylamide nuciferine derivative prepared by the present invention can inhibit the expression of URAT1 in HK-2 cells, promote uric acid excretion, thereby reducing uric acid levels, which is of great significance for the further development of new uric acid-lowering drugs. The alkylamide nuciferine derivative with uric acid-lowering and kidney-protecting effects provided by the present invention has a simple synthesis method, low raw material price, and novel structure.

Description

Technical Field

[0001] The present invention belongs to the field of drug synthesis, and specifically relates to an alkylamide nuciferine derivative having both uric acid-lowering and kidney-protecting activities, and a preparation method and application thereof. Background Art

[0002] Hyperuricemia is a disease caused by impaired purine metabolism and can lead to a range of complications, including gout, hypertension, and diabetes. Currently, clinical medications for hyperuricemia, such as allopurinol, probenecid, and benzbromarone, can cause chronic damage to the urinary system, including the kidneys, and can easily form urate crystals and stones.

[0003] Nuciferine is a kind of Nelumbo nucifera Gaertn ) Alkaloids extracted from the plant. Pharmacological studies have shown that it possesses a variety of pharmacological activities, including antioxidant, anti-obesity, anti-inflammatory, anti-atherosclerotic, antiviral, and anti-tumor properties. Due to its low toxicity and minimal side effects, nuciferine has become a hot topic in pharmaceutical research and holds broad development prospects.

[0004] Wang Mingxing and others discovered through experiments that nelumbo nucifera in lotus leaves can reduce serum urate and improve renal function. It can also inhibit the production of renal interleukins in mice with hyperuricemia caused by potassium oxonate. It was reported for the first time that nelumbo nucifera can exert anti-inflammatory and anti-hyperuricemic effects by regulating organic ion transporters and inflammatory signals in renal hyperuricemia. The study found that daily use of supplements rich in nelumbo nucifera can effectively protect and prevent nephritic hyperuricemia. However, the uric acid-lowering activity of nelumbo nucifera is low and cannot be directly used as a clinical uric acid-lowering drug. The development of a more effective uric acid-lowering drug has become an urgent problem to be solved. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides an alkylamide nuciferine derivative having both uric acid-lowering and kidney-protecting activities.

[0006] The present invention also provides a preparation method of the alkylamide nuciferine derivative.

[0007] The present invention further provides the use of the above-mentioned alkylamide nuciferine derivatives in the preparation of drugs for treating uric acid reduction or protecting the kidneys.

[0008] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are as follows:

[0009] The present invention provides an alkylamide nuciferine derivative having both uric acid-lowering and kidney-protecting activities, and its molecular structure is as follows:

[0010] ;

[0011] R is 、 、 、 、 、 、 、 .

[0012] The present invention also provides a method for preparing the above-mentioned alkylamide nuciferine derivative, comprising the following steps:

[0013] (1) Dissolve nuciferine in methanol, then add hydrogen peroxide and stir to react; after the reaction is completed, adjust the pH value of the reaction solution, then add distilled water, extract with chloroform, dry the chloroform layer with anhydrous Na2SO4, filter to remove the solid, concentrate the filtrate under reduced pressure, separate and elute with silica gel column chromatography to obtain nuciferine- N - oxides;

[0014] (2) Under ice bath conditions, N The oxide is dissolved in methanol, and then a methanol solution of FeSO4·7H2O is added. The reaction is stirred after removing the ice bath to obtain a reaction solution. A saturated NaHCO3 solution is added to the reaction solution and the reaction is continued. After the reaction is completed, distilled water is added, and the mixture is extracted with chloroform. The chloroform layer is dried over anhydrous Na2SO4, the solid is removed by filtration, and the mixture is evaporated to dryness under reduced pressure. The mixture is separated by silica gel column chromatography and eluted to obtain protonuciferine.

[0015] (3) Dissolve proto-nuciferine and triethylamine in anhydrous DCM, slowly add RX dropwise while maintaining the temperature at 0°C, and stir to react. After the reaction is complete, quench the reaction, extract the reaction solution with dichloromethane, dry it with anhydrous sodium sulfate, concentrate the filtrate, and obtain the target compound by column chromatography.

[0016] Furthermore, in step (1), the ratio of nuciferine to hydrogen peroxide is 1 mmol:7.5 mL.

[0017] Furthermore, in step (1), the stirring reaction is carried out at room temperature for 24 hours; the pH is adjusted to 10 using a 3M NaOH aqueous solution; and elution is performed using an eluent consisting of chloroform: methanol: triethylamine in a volume ratio of 30:1:1‰.

[0018] Furthermore, in step (2), nuciferine- N -oxide and FeSO4·7H2O molar ratio is 1:2; the concentration of FeSO4·7H2O methanol solution is 1 mol / L; N -oxide and saturated NaHCO3 solution ratio is 1mmol:10mL;.

[0019] Furthermore, in step (2), the stirring reaction is carried out at room temperature for 12 hours; the reaction is continued for 20 minutes; and the eluent composed of chloroform: methanol: triethylamine in a volume ratio of 10:1:1‰ is used for elution.

[0020] Furthermore, in step (3), the molar ratio of protonuciferine, triethylamine and RX is 1:2-5:1-2.

[0021] Furthermore, in step (3), the stirring reaction is carried out at room temperature for 10-12 hours; and saturated sodium bicarbonate is used to quench the reaction.

[0022] The present invention also provides the use of the alkylamide nuciferine derivatives in the preparation of uric acid-lowering or kidney-protecting drugs.

[0023] The reaction route for preparing alkylamide nuciferine derivatives of the present invention is:

[0024]

[0025] The beneficial effects of the present invention are:

[0026] (1) The present invention improves the biological activity of nuciferine in lowering uric acid by introducing active groups to modify its structure. Cell experiments have shown that the alkylamide nuciferine derivatives prepared by the present invention can inhibit the expression of URAT1 in HK-2 cells and promote uric acid excretion, thereby reducing uric acid levels. This is of great significance for the further development of new uric acid-lowering drugs.

[0027] (2) The alkylamide nuciferine derivatives provided by the present invention have uric acid-lowering and kidney-protecting effects, and have a simple synthesis method, low raw material price, and novel structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 1H spectrum of compound 9 prepared in Example 1;

[0029] Figure 2 C chromatogram of compound 9 prepared in Example 1;

[0030] Figure 3 HRMS pattern of compound 9 prepared in Example 1;

[0031] Figure 4 1H spectrum of compound 28 prepared in Example 2;

[0032] Figure 5 C chromatogram of compound 28 prepared in Example 2;

[0033] Figure 6 HRMS pattern of compound 28 prepared in Example 2;

[0034] Figure 7 1H spectrum of compound 11 prepared in Example 3;

[0035] Figure 8 C chromatogram of compound 11 prepared in Example 3;

[0036] Figure 9 HRMS pattern of compound 11 prepared in Example 3;

[0037] Figure 10 1H spectrum of compound 16 prepared in Example 4;

[0038] Figure 11 C chromatogram of compound 16 prepared in Example 4;

[0039] Figure 12 HRMS pattern of compound 16 prepared in Example 4;

[0040] Figure 13 1H spectrum of compound 21 prepared in Example 5;

[0041] Figure 14 C chromatogram of compound 21 prepared in Example 5;

[0042] Figure 15 HRMS pattern of compound 21 prepared in Example 5;

[0043] Figure 16 Proton spectrum of compound 3 prepared in Example 6;

[0044] Figure 17 C12 spectra of compound 3 prepared in Example 6;

[0045] Figure 18 HRMS pattern of compound 3 prepared in Example 6;

[0046] Figure 19 1H spectrum of compound 17 prepared in Example 7;

[0047] Figure 20 C12 spectra of compound 17 prepared in Example 7;

[0048] Figure 21 HRMS pattern of compound 17 prepared in Example 7;

[0049] Figure 22 1H spectrum of compound 10 prepared in Example 8;

[0050] Figure 23 C chromatogram of compound 10 prepared in Example 8;

[0051] Figure 24HRMS pattern of compound 10 prepared in Example 8;

[0052] Figure 25 1H spectrum of compound 4 prepared in Example 9;

[0053] Figure 26 C12 spectra of compound 4 prepared in Example 9;

[0054] Figure 27 HRMS chart of compound 4 prepared in Example 9. DETAILED DESCRIPTION

[0055] The technical solution of the present invention is further explained and illustrated by means of specific embodiments below.

[0056] Unless otherwise specified, the raw materials used in the present invention are commercially available.

[0057] Example 1

[0058] (1) Nuciferine (0.295 g, 1 mmol) was dissolved in 15 mL of methanol, and then 7.5 mL of 30% H2O2 was added to the solution. The mixture was stirred at room temperature for 24 h. After the reaction, 3M NaOH aqueous solution was added to the reaction solution to adjust the pH to 10. Then 150 mL of distilled water was added and the mixture was extracted with chloroform three times (600 mL×3). The chloroform layer was dried over anhydrous Na2SO4, the solid was removed by filtration, and the filtrate was concentrated under reduced pressure. The mixture was separated by silica gel column chromatography and eluted with chloroform: methanol: triethylamine (30:1:1‰ v / v / v) to obtain nuciferine- N -Oxide.

[0059] (2) Under ice bath conditions, N -oxide (0.310 g, 1 mmol) was dissolved in 2 mL of methanol, followed by the addition of a 2 mL solution of FeSO₄·7H₂O (0.304 g, 2 mmol) in methanol. The ice bath was removed and the reaction was stirred at room temperature for 12 h. Finally, 10 mL of saturated NaHCO₃ solution was added to the reaction solution and the reaction was continued for 20 min. After the reaction, 90 mL of distilled water was added to the three-necked flask, and the mixture was extracted three times with chloroform (100 mL x 3). The chloroform layer was dried over anhydrous Na₂SO₄, the solid was removed by filtration, and the mixture was evaporated to dryness under reduced pressure. Protonuciferine was obtained by silica gel column chromatography, eluting with chloroform:methanol:triethylamine (10:1:1‰).

[0060] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). 4-Bromobutyryl chloride (0.52 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 9 as a white powder with mp 242.4–243.4 °C.

[0061] The structural formula of compound 9 is:

[0062]

[0063] like Figure 1-Figure 3 As shown:

[0064] 1 H NMR (600 MHz, CDCl3) δ 8.48 (s, 1H), 7.45 – 7.13 (m, 3H), 6.71 (s,1H), 5.21 – 4.35 (m, 2H), 3.91 (s, 3H), 3.67 (s, 3H), 3.45 – 3.08 (m, 1H), 3.05 – 2.60 (m, 4H), 1.95 – 1.65 (m, 1H), 1.20 – 0.95 (m, 2H), 0.90 – 0.65(m, 2H).

[0065] 13 C NMR (151 MHz, CDCl3) δ 172.96, 152.27, 145.69, 136.28, 131.82,128.75, 128.54, 128.04, 127.79, 127.43, 126.93, 125.73, 111.63, 60.06, 55.99,52.92, 41.01, 37.03, 29.98, 11.57, 8.17, 7.11.

[0066] HRMS calcd for C 22 H 24 BrNO3: [M-HBr+Na] + 372.1576, found 372.1581.

[0067] Example 2

[0068] Steps (1) and (2) are the same as in Example 1;

[0069] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Bromoacetyl chloride (0.06 g, 0.38 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After completion of the reaction, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 28 as a white powder with mp 180.9-181.9 °C.

[0070] The structural formula of compound 28 is:

[0071]

[0072] like Figure 4-Figure 6 As shown:

[0073] 1 H NMR (600 MHz, CDCl3) δ 8.44 (t, J = 9.8 Hz, 1H), 7.37 – 7.23 (m, 3H), 6.68 (s, 1H), 5.00 (t, J = 37.1 Hz, 1H), 4.70 – 4.20 (m, 1H), 4.20 – 4.00 (m,2H), 3.91 (s, 3H), 3.67 (s, 3H), 3.40 – 4.10 (m, 1H), 3.10 – 2.67 (m, 4H).

[0074] 13 C NMR (151 MHz, DMSO) δ 165.51, 152.28, 145.54, 137.00, 131.67,129.87, 128.95, 128.39, 128.19, 127.41, 126.93, 125.58, 112.76, 60.02, 56.29,50.90, 43.08, 41.42, 33.82, 30.29.

[0075] HRMS calcd for C 20 H 20 NO3Br: [M+Na] + 424.0524, found 424.0522.

[0076] Example 3

[0077] Steps (1) and (2) are the same as in Example 1;

[0078] (3) Protonurine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). 2-Chloropropionyl chloride (0.05 g, 0.39 mmol) was slowly added dropwise at 0 °C. The reaction mixture was stirred at room temperature overnight. After completion of the reaction, the reaction mixture was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 11 as a white powder with mp 216.8–217.8 °C.

[0079] The structural formula of compound 11 is:

[0080]

[0081] like Figure 7-Figure 9 As shown:

[0082] 1 H NMR (600 MHz, DMSO) δ 8.30 (d, J = 7.7 Hz, 1H), 7.33 (dd, J = 16.6,9.1 Hz, 2H), 7.27 (t, J = 7.2 Hz, 1H), 6.92 (s, 1H), 5.21 (dq, J = 18.8, 6.2 Hz,1H), 4.97 – 4.67 (m, 1H), 4.22 (d, J = 9.9 Hz, 1H), 3.84 (s, 3H), 3.60 (s, 3H), 3.23 (t, J = 12.1 Hz, 1H), 3.01 – 2.75 (m, 3H), 1.57 (dd, J = 12.2, 6.4 Hz, 3H).

[0083] 13C NMR (151 MHz, CDCl3) δ 166.27, 151.15, 144.81, 135.38, 130.46,127.99, 127.51, 127.38, 126.82, 126.74, 126.03, 124.95, 110.20, 59.02, 54.96,50.42, 49.15, 40.44, 33.05, 29.31, 19.87.

[0084] HRMS calcd for C 21 H 22 NO3Br: [M+Na] + 438.0681, found 438.0684.

[0085] Example 4

[0086] Steps (1) and (2) are the same as in Example 1;

[0087] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Cyclopentanecarbonyl chloride (0.05 g, 0.38 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 16 as a white powder with mp 180.3–181.3 °C.

[0088] The structural formula of compound 16 is:

[0089]

[0090] like Figure 10-12 As shown:

[0091] 1 H NMR (600 MHz, CDCl3) δ 8.46 (dd, J = 41.1, 7.6 Hz, 1H), 7.44 – 7.18(m, 3H), 6.69 (d, J = 26.7 Hz, 1H), 5.03 (dd, J = 57.7, 10.7 Hz, 1H), 4.44 (dd, J=306.4, 12.9 Hz, 1H), 3.90 (s, 3H), 3.67 (s, 3H), 3.30 – 3.09 (m, 1H), 3.07 –2.96 (m, 1H), 2.94 – 2.61 (m, 4H), 2.10 – 1.45 (m, 8H).

[0092] 13 C NMR (151 MHz, CDCl3) δ 174.46, 151.99, 145.81, 137.01, 131.56,128.58, 128.34, 127.85, 127.69, 127.42, 126.88, 125.83, 111.20, 60.02, 55.99,50.76, 42.10, 40.93, 33.99, 31.01, 30.14, 29.73, 26.50, 26.03.

[0093] HRMS calcd for C 24 H 27 NO3: [M+Na] + 400.1889, found 400.1891.

[0094] Example 5

[0095] Steps (1) and (2) are the same as in Example 1;

[0096] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Cyclohexanecarbonyl chloride (0.06 g, 0.41 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 21 as a light yellow powder with mp 157.8–158.8°C.

[0097] The structural formula of compound 21 is:

[0098]

[0099] like Figure 13-15 As shown:

[0100] 1 H NMR (600 MHz, CDCl3) δ 8.34 (d, J= 6.0 Hz, 1H), 7.39 – 7.21 (m, 2H), 7.17 – 7.00 (m, 1H), 6.61 (s, 1H), 5.00 (d, J = 12.5 Hz, 1H), 4.06 (d, J = 10.8Hz, 1H), 3.83 (s, 3H), 3.60 (s, 3H), 3.21 – 3.17 (m, 1H), 2.99 – 2.58 (m,4H), 2.50 – 2.38 (m, 1H), 1.87 – 1.43 (m, 8H), 1.26 – 1.19 (m, 2H).

[0101] 13 C NMR (151 MHz, DMSO) δ 174.18, 152.12, 145.53, 137.42, 131.75, 130.00, 128.88, 128.35, 128.07, 127.25, 126.98, 126.39, 112.66, 59.99, 56.28,50.18, 34.05, 30.93, 29.76, 29.31, 26.11, 25.72, 25.63.

[0102] HRMS calcd for C 25 H 29 NO3: [M+Na] + 414.2045, found 414.2049.

[0103] Example 6

[0104] Steps (1) and (2) are the same as in Example 1;

[0105] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Acetoxyacetyl chloride (0.05 g, 0.37 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 3 as a white powder with mp 163.8–164.8 °C.

[0106] The structural formula of compound 3 is:

[0107]

[0108] like Figure 16-Figure 18 As shown:

[0109] 1 H NMR (600 MHz, CDCl3) δ 8.36 (s, 1H), 7.36 – 7.19 (m, 3H), 6.60 (s,1H), 5.12 – 4.82 (m, 1H), 4.80 – 4.70 (m, 2H), 4.63 – 4.37 (m, 1H), 3.83 (s, 3H), 3.60 (s, 3H), 3.33 – 2.94 (m, 2H), 2.84 – 2.66 (m, 49.3 Hz, 3H), 2.13 (s, 3H).

[0110] 13 C NMR (151 MHz, CDCl3) δ 170.70, 164.98, 152.24, 145.95, 136.40,131.43, 128.58, 128.42, 127.98, 127.85, 127.59, 127.06, 125.75, 111.26,62.01, 60.04, 55.98, 50.95, 40.18, 33.95, 30.51, 20.69.

[0111] HRMS calcd for C 22 H 23 NO5: [M+Na] + 404.1474, found 404.1478.

[0112] Example 7

[0113] Steps (1) and (2) are the same as in Example 1;

[0114] (3) Protothecin (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Ethyl chloroformate (0.06 g, 0.40 mmol) was slowly added dropwise at 0 °C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 17 as a white powder with mp 126.3–127.3 °C.

[0115] The structural formula of compound 17 is:

[0116]

[0117] like Figures 19-21 As shown:

[0118] 1 H NMR (600 MHz, CDCl3) δ 8.45 (dd, J = 26.4, 7.9 Hz, 1H), 7.40 – 7.20(m, 3H), 6.68 (d, J = 24.2 Hz, 1H), 5.13 – 4.92 (m, 1H), 4.30 – 4.13 (m, 2H), 3.96 – 3.86 (m, 4H), 3.67 (s, 3H), 3.63 – 3.44 (m, 2H), 3.33 (t, J = 12.4 Hz,1H), 3.18 – 3.05 (m, 1H), 2.97 – 2.65 (m, 3H), 1.26 (dt, J = 49.0, 7.1 Hz, 3H).

[0119] 13 C NMR (151 MHz, CDCl3) δ 167.68, 164.64, 152.17, 145.89, 136.59,131.47, 128.63, 128.39, 127.85, 127.79, 127.55, 127.01, 126.09, 111.22,61.56, 60.03, 55.99, 50.96, 42.42, 42.16, 33.72, 30.57, 14.19.

[0120] HRMS calcd for C 23 H 25 NO5: [M+Na] + 418.1630, found 418.1633.

[0121] Example 8

[0122] Steps (1) and (2) are the same as in Example 1;

[0123] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). Ethyl oxalyl chloride (0.05 g, 0.37 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 10 as a white powder with mp 167.7–168.7 °C.

[0124] The structural formula of compound 10 is:

[0125]

[0126] like Figure 22-24 As shown:

[0127] 1 H NMR (600 MHz, CDCl3) δ 8.44 (d, J = 8.0 Hz, 1H), 7.37 – 7.31 (m, 1H), 7.30 – 7.22 (m, 2H), 6.68 (d, J = 17.7 Hz, 1H), 5.07 – 4.75 (m, 1H), 4.43 –4.37 (m, 1H), 4.33 – 4.18 (m, 1H), 3.93 – 3.84 (m, 4H), 3.67 (d, J = 4.9 Hz,3H), 3.38 (td, J = 12.8, 2.2 Hz, 1H), 3.17 – 3.06 (m, 1H), 3.06 – 2.95 (m, 1H), 2.95 – 2.81 (m, 1H), 2.78 – 2.66 (m, 1H), 1.34 (dt, J = 87.6, 7.2 Hz, 3H).

[0128] 13C NMR (151 MHz, CDCl3) δ 162.91, 161.11, 152.42, 146.04, 135.99,131.39, 128.67, 128.49, 127.93, 127.83, 127.43, 127.21, 124.96, 111.39,62.22, 60.06, 56.00, 50.48, 42.06, 33.82, 30.45, 14.07.

[0129] HRMS calcd for C 22 H 23 NO5: [M+Na] + 404.1474, found 404.1476.

[0130] Example 9

[0131] Steps (1) and (2) are the same as in Example 1;

[0132] (3) Protonuciferine (0.10 g, 0.31 mmol) and triethylamine (0.12 mL, 0.86 mmol) were dissolved in anhydrous DCM (20 mL). 2-Bromopropionyl chloride (0.06 g, 0.35 mmol) was slowly added dropwise at 0°C. The reaction mixture was stirred at room temperature overnight. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate (25 mL). The reaction mixture was extracted with dichloromethane (2 × 25 mL) and dried over anhydrous sodium sulfate. The filtrate was concentrated and purified by column chromatography to obtain the target compound 4 as a white powder with mp 148.7-149.7 °C.

[0133] The structural formula of compound 4 is:

[0134]

[0135] like Figure 25-27 As shown:

[0136] 1 H NMR (600 MHz, DMSO) δ 8.30 (d, J = 7.7 Hz, 1H), 7.33 (dd, J = 16.6,9.1 Hz, 2H), 7.27 (t, J = 7.2 Hz, 1H), 6.92 (s, 1H), 5.21 (dq, J = 18.8, 6.2 Hz,1H), 4.97 – 4.67 (m, 1H), 4.22 (d,J = 9.9 Hz, 1H), 3.84 (s, 3H), 3.60 (s, 3H), 3.23 (t, J = 12.1 Hz, 1H), 3.01 – 2.75 (m, 3H), 1.57 (dd, J = 12.2, 6.4 Hz, 3H).

[0137] 13 C NMR (151 MHz, CDCl3) δ 166.27, 151.15, 144.81, 135.38, 130.46,127.99, 127.51, 127.38, 126.82, 126.74, 126.03, 124.95, 110.20, 59.02, 54.96,50.42, 49.15, 40.44, 33.05, 29.31, 19.87.

[0138] HRMS calcd for C 21 H 22 NO3Br: [M+Na] + 438.0681, found 438.0684.

[0139] Effect verification

[0140] (I) Cell culture and drug administration

[0141] Cell passaging: When HK-2 cells grow to a density of 85%-90%, the cells are passaged. Place the cells in a clean bench, discard the old culture medium with a pipette, add 4.0 mL of PBS to wash, discard the PBS, and repeat 2-3 times. Use a pipette to add 1.0 mL of 0.25% trypsin to digest for 40 seconds, aspirate the trypsin with a pipette, add culture medium and repeatedly pipette until a single cell suspension is obtained. Take 1.0 mL of the cell suspension and transfer it to a new culture dish, add 7 mL of culture medium, shake well, and transfer the culture dish to a cell culture incubator after microscopic observation.

[0142] Uric acid induction and drug administration. When HK-2 cells have successfully recovered and stably passaged for more than three generations, and the cell density in the culture dish reaches 85%-90%, remove the cells from the incubator and place them on a clean bench. Discard the culture medium and wash three times with PBS to remove dead cells. Add culture medium containing 100 mg / L uric acid and a certain amount of the compound solution prepared in the examples (final concentration of the compound is 50 μM) to the cell culture dishes in the model and drug groups, shake well, label, and transfer to an incubator for 48 hours for protein extraction and quantitative analysis.

[0143] (II) Cell protein quantification experiment

[0144] Take the protein standard solution from the BCA kit and add it to the protein standard to prepare a 1 mg / mL protein solution. Dilute the solution to concentrations of 0.5, 0.4, 0.2, 0.1, and 0.05 mg / mL for subsequent sample loading. Prepare the BCA colorimetric reagent in a 50.0 mL centrifuge tube according to the kit instructions. Add 25 µL of the diluted protein solution to a 96-well plate, setting up three replicates for each concentration. Thaw the extracted cell protein in advance and dilute it 40- to 80-fold. Add 25 µL of the protein solution to each well of a 96-well plate, setting up three replicates for each concentration. After protein loading, add 125 µL of the BCA colorimetric reagent and incubate in a constant temperature incubator for half an hour. Read at 562 nm using a microplate reader. Construct a protein standard curve based on the absorbance values. Substitute the absorbance values ​​of the protein to be tested into the curve to determine the protein concentration.

[0145] (3) Western-Blot

[0146] Prepare gel. Take a professional gel-making glass plate, clean it, and dry it. Clamp it onto a mold and inject the lower layer of gel prepared according to the instructions for preparing polyacrylamide gel (PAGE). Seal and flatten the gel surface with Wahaha water. Let it stand at room temperature for 20-30 minutes. Once the gel and water layers are clearly separated, discard the Wahaha water and inject the 5% upper layer of gel prepared according to the instructions. Insert a 10-well comb and let it stand at room temperature again for 20-30 minutes. Insert the prepared gel into the electrophoresis tank, fill it with the prepared 1x electrophoresis buffer, and remove the comb vertically. Add 5 µL of protein marker to each well and 60 µg of the quantified protein to the experimental well. Connect the power supply to a constant voltage of 120 V and set the desired time for electrophoresis. After electrophoresis, transfer the gel to the membrane. Cut a 10-well strip of polyvinylidene fluoride (PVDF) membrane and activate it in methanol before transferring the gel to the membrane. After electrophoresis, the constant current was 300 mA and electrotransfer was performed for 60-75 min.

[0147] The transferred PVDF membrane was cut along a protein marker to identify the target bands URAT1 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The membrane was then placed in 3.0 mL of pre-chilled 5% milk blocking buffer and blocked on a shaker for 2 hours. The blocked target bands were placed in an antibody incubation box, and URAT1 (GLUT9) and GAPDH antibodies diluted according to the manufacturer's instructions were added. The membrane was incubated overnight at 4°C. The next day, the URAT1 (GLUT9) and GAPDH solutions were discarded, and the membrane was washed three times with TBST on a shaker for 5 minutes each. The corresponding secondary antibody was added and incubated on a shaker for another 2 hours. After binding to the secondary antibody, the membrane was washed, enhanced chemiluminescence reagent was added, and the membrane was scanned and photographed using a chemiluminescence imaging system. The grayscale values ​​of the protein bands were analyzed using ImageJ, and GraphPad Prism 8.0 software was used to plot the expression of URAT1 (GLUT9) in each cell group. The percentage of protein expression was calculated based on the URAT1 protein expression in the blank group. The results are shown in Table 1.

[0148] Table 1 Experimental results of compounds (50 μM) inhibiting URAT1 expression in HK-2 cells

[0149]

Claims

1. An alkylamide nuciferine derivative having both uric acid-lowering and kidney-protecting activities, characterized in that: Its molecular structure is: ； R is 、 、 、 、 、 、 、 .

2. A method for preparing the alkylamide nuciferine derivative according to claim 1, characterized in that: The following steps are involved: (1) Dissolve nuciferine in methanol, then add hydrogen peroxide and stir to react; after the reaction is completed, adjust the pH value of the reaction solution, then add distilled water, extract with chloroform, dry the chloroform layer with anhydrous Na2SO4, filter to remove the solid, concentrate the filtrate under reduced pressure, separate and elute with silica gel column chromatography to obtain nuciferine- N - oxides; (2) Under ice bath conditions, N The oxide is dissolved in methanol, and then a methanol solution of FeSO4·7H2O is added. The reaction is stirred after removing the ice bath to obtain a reaction solution. A saturated NaHCO3 solution is added to the reaction solution and the reaction is continued. After the reaction is completed, distilled water is added, and the mixture is extracted with chloroform. The chloroform layer is dried over anhydrous Na2SO4, the solid is removed by filtration, and the mixture is evaporated to dryness under reduced pressure. The mixture is separated by silica gel column chromatography and eluted to obtain protonuciferine. (3) Dissolve proto-nuciferine and triethylamine in anhydrous DCM, slowly add RX dropwise while maintaining the temperature at 0°C, and stir to react. After the reaction is complete, quench the reaction, extract the reaction solution with dichloromethane, dry it with anhydrous sodium sulfate, concentrate the filtrate, and obtain the target compound by column chromatography.

3. The preparation method according to claim 2, characterized in that In step (1), the ratio of nuciferine to hydrogen peroxide is 1 mmol:7.5 mL.

4. The preparation method according to claim 2 or 3, characterized in that In step (1), the stirring reaction is carried out at room temperature for 24 hours; the pH is adjusted to 10 using a 3M NaOH aqueous solution; and elution is performed using an eluent consisting of chloroform: methanol: triethylamine in a volume ratio of 30:1:1‰.

5. The preparation method according to claim 2, characterized in that In step (2), nuciferine- N -oxide and FeSO4·7H2O molar ratio is 1:2; the concentration of FeSO4·7H2O methanol solution is 1 mol / L; N The ratio of -oxide and saturated NaHCO3 solution is 1 mmol:10 mL.

6. The preparation method according to claim 2 or 5, characterized in that In step (2), the stirring reaction is carried out at room temperature for 12 hours; the reaction is continued for 20 minutes; and the eluent composed of chloroform: methanol: triethylamine in a volume ratio of 10:1:1‰ is used for elution.

7. The preparation method according to claim 2, characterized in that In step (3), the molar ratio of protonuciferine, triethylamine and RX is 1:2-5:1-2.

8. The preparation method according to claim 2 or 7, characterized in that In step (3), the stirring reaction is carried out at room temperature for 10-12 hours; and saturated sodium bicarbonate is used to quench the reaction.

9. Use of the alkylamide nuciferine derivative according to claim 1 in the preparation of a uric acid-lowering drug.

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