N-aryl nuciferine derivative as well as preparation method and application thereof

Abstract

The invention discloses an N-aryl nuciferine derivative and a preparation method and application thereof.The chemical structure of the N-aryl nuciferine derivative is shown in the formula I. In the formula I, an aromatic ring A is selected from a benzene ring, a naphthalene ring, biphenyl or nitrogen heteroaromatic ring; r is selected from an electron-donating group and an electron-withdrawing group, or two ends of R are connected with an aromatic ring A to form a ring, the substitution number of the electron-donating group is 1-2, and the substitution number of the electron-withdrawing group is 1. The N-arylated nuciferine derivative disclosed by the invention has anti-lipase activity superior to that of a parent compound, can inhibit lipid accumulation in a cell differentiation process, and has further development potential.

Description

Technical Field

[0001] The present invention relates to a nuciferine derivative, in particular to an N-aryl nuciferine derivative and a preparation method and application thereof. Background Art

[0002] Obesity is a chronic disease caused by multiple factors. It not only places a physical and mental burden on individuals but also induces a series of intractable weight-related diseases. Obesity poses a serious threat to health. It can trigger inflammation and insulin resistance, leading to metabolic disorders, significantly increasing the risk of chronic metabolic diseases such as diabetes, fatty liver disease, and cardiovascular disease, ultimately leading to a decline in quality of life and a shortened lifespan. Although lifestyle interventions have shown some effectiveness in controlling obesity, and moderate exercise can effectively alleviate obesity and promote the prevention and recovery of chronic metabolic diseases such as type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease, the difficulty in maintaining adherence to lifestyle interventions limits their therapeutic efficacy and the achievement of health outcomes. Therefore, the development and use of anti-obesity drugs has become a current research hotspot and has received widespread attention.

[0003] Orlistat, a highly effective lipase inhibitor, was launched in the United States in 1999 and is currently the only drug recommended for the treatment of obesity. It is indicated for patients with a BMI exceeding 28 kg / m² and other risk factors or comorbidities, or for patients with a BMI ≥30 kg / m² who have lost less than 5% of their body weight after six months of treatment with a basic regimen. Although most traditional anti-obesity drugs have demonstrated some degree of weight loss efficacy, maintaining long-term therapeutic effects remains a major challenge in obesity management. The mechanisms of action and safety profiles of various compounds in anti-obesity drugs remain unclear. Furthermore, drug abuse, misuse, and dependence have emerged. Morbidly obese patients also face surgical complications such as infection, deep vein thrombosis, anemia, and malnutrition. Therefore, there is an urgent need for medical researchers to discover and develop new, more effective treatments for obesity.

[0004] Lotus leaf is a common Chinese medicine. It is a plant of the Nymphaeaceae family. Nelumbo nucifera The dried leaves of the lotus plant (Gaertn) possess unique medicinal value. The Compendium of Materia Medica states that "taking lotus leaves can make one thinner," suggesting their weight-regulating properties. Later, the Bencao Qiuzhen (Compendium of Materia Medica) also mentions lotus leaves as "able to dispel summer heat, disperse blood stasis, and promote diuresis," suggesting their potential role in regulating abnormal lipid metabolism.

[0005] Nuciferine is a alkaloid extracted from the water lily plant Nelumbo nucifera Nelumbo nuciferaNuciferine is an aporphine alkaloid extracted from the dried leaves of Nelumbo nucifera Gaertn. Compared with traditional chemical drugs, Nuciferine exhibits a series of amazing unique properties. It not only has a significant anti-obesity effect and can effectively inhibit excessive weight gain, but also exhibits excellent anti-dyslipidemia function and helps maintain lipid balance in the blood. Nuciferine also performs outstandingly in anti-hyperglycemia and can help regulate blood glucose levels and relieve symptoms related to diabetes. In addition, Nuciferine can also resist hypouricemia, reduce the risk of gout, and resist tumor and other diseases.

[0006] Although some progress has been made in the lipid-lowering mechanism of Nuciferine, there are still many problems, such as potential structure-activity relationship and optimal dosage, which need to be further studied. As a natural plant-derived active ingredient, Nuciferine has the advantages of wide source and fewer side effects, and is expected to provide new strategies for the prevention and treatment of obesity and related metabolic diseases. Therefore, it is of great research value and significance to effectively modify Nuciferine and explore its biological activity and intrinsic structure-activity relationship.

[0007] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the present disclosure, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0008] The purpose of the present application is to provide a N-aryl Nuciferine derivative, a preparation method and application thereof. The N-aryl Nuciferine derivative has significant lipase inhibition and adipocyte lipid accumulation inhibition activity, and has further development potential.

[0009] In order to achieve the above-mentioned purpose, the present application provides a N-aryl Nuciferine derivative, the chemical structure of which is shown in formula I: In formula I, the aromatic ring A is selected from a benzene ring, a naphthalene ring, a biphenyl, or a nitrogen heteroaromatic ring; R is selected from an electron-donating group, an electron-withdrawing group, or a ring connected to the aromatic ring A at both ends, wherein the number of substitutions of the electron-donating group is 1-2, and the number of substitutions of the electron-withdrawing group is 1.

[0010] Preferably, the electron-donating group is selected from a methyl group or a methoxy group; and the electron-withdrawing group is selected from a halogen or a trifluoromethyl group.

[0011] Preferably, the electron-donating group is selected from a methoxy group; and the electron-withdrawing group is selected from fluorine, bromine, or a trifluoromethyl group.

[0012] Preferably, the chemical structure of the N-aryl nuciferine derivative is selected from any one of the following: .

[0013] The second object of the present invention is to provide a method for preparing the N-aryl nuciferine derivative, which comprises: Pd2(dba)3 or Ph3P and BINAP are dissolved in dry toluene and continuously stirred at room temperature to ensure that the catalyst is fully dissolved and activated. Subsequently, demethylnuciferine, a bromide represented by formula II, and Cs2CO3 are added under an inert atmosphere, and the reaction mixture is heated to 70±5°C to react to obtain the N-arylnuciferine derivative; wherein the molar ratio of Pd2(dba)3 or Ph3P, BINAP, Cs2CO3, and demethylnuciferine is 0.1:0.2:1~1.5:1.

[0014] Preferably, the molar ratio of the bromide to demethylnuciferine is 2:1; or / and, the mass ratio of the volume of toluene to demethylnuciferine is 2 mL:30 g; or / and, after the reaction is completed, extraction is performed using ethyl acetate, the organic phase is collected, dried, concentrated, and the product is obtained by separation and purification.

[0015] Preferably, the preparation method of demethylnuciferine comprises: dissolving nuciferine in dichloromethane, cooling the entire reaction solution to -20 ° C, and slowly adding m -CPBA in dichloromethane solution, continue stirring at low temperature, then move to room temperature and continue stirring. When the raw material is converted into the intermediate product nuciferine nitrogen oxide, the reaction solution is cooled to -20 ° C again, methanol is added, and FeSO4·7H2O is added to the reaction solution. Then, the mixture is continued to stir at low temperature, then moved to room temperature and stirred to react to obtain demethylnuciferine.

[0016] More preferably, the nuciferine and m The molar ratio of -CPBA and FeSO4·7H2O is 6.8:5.8:13.4; or / and the ratio of the mass of nuciferine to the volume of dichloromethane and methanol is 1 g:10 mL:12.5 mL.

[0017] The third object of the present invention is to provide the use of the N-aryl nuciferine derivatives in the preparation of anti-obesity drugs.

[0018] The fourth object of the present invention is to provide the use of the N-aryl nuciferine derivatives in the preparation of drugs for inhibiting lipid accumulation and / or inhibiting lipase activity.

[0019] The N-aryl nuciferine derivatives of the present invention, and their preparation methods and applications have the following advantages: This invention utilizes a palladium-catalyzed Buchwald-Hartwig coupling reaction to design and synthesize 21 novel N-arylnuciferine derivatives. These derivatives were tested for in vitro lipase inhibition. The results demonstrate that the N-arylated nuciferine derivatives exhibit superior anti-lipase activity compared to the parent compound, with compound 2n exhibiting the highest lipase inhibition, four times that of the parent compound. Furthermore, lipid accumulation assays in 3T3-L1 preadipocytes revealed that compounds 2k, 2l, 2e, 2g, 2m, 2i, and 2o all inhibited lipid accumulation during cell differentiation to varying degrees, with compounds 2i and 2g demonstrating the most significant effects. Therefore, the N-arylnuciferine derivatives of this invention exhibit significant lipase inhibition and adipocyte lipid accumulation inhibition, demonstrating potential for further development. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the Oil Red O staining result of the in vitro lipid-lowering activity assay of the 3T3-L1 preadipocyte cell line of the present invention.

[0021] Figure 2 The content of Oil Red O in the in vitro lipid-lowering activity assay of the 3T3-L1 preadipocyte cell line of the present invention. DETAILED DESCRIPTION

[0022] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0023] Note: If specific conditions are not specified in the examples, the experiments were conducted under conventional conditions or those recommended by the manufacturer. Instruments used without manufacturer information are commercially available. Raw materials and reagents used without manufacturer information are commercially available or can be prepared by known methods.

[0024] Throughout this disclosure, all features, such as values, amounts, amounts, and concentrations, specified in numerical ranges or percentage ranges are provided for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to encompass and specifically disclose all possible subranges and individual values ​​within those ranges (including integers and fractions).

[0025] The features described in this disclosure may be combined in any manner, and as long as there are no conflicts between the combinations of these features, all possible combinations should be considered within the scope of this specification. Each feature disclosed in this specification may be replaced by any alternative feature that provides the same, equivalent, or similar purpose. Therefore, unless otherwise specified, the features disclosed are merely general examples of equivalent or similar features.

[0026] 1. Preparation of N-demethylnuciferine The nitrogen atom on the B ring of nuciferine is a tertiary amine. In order to carry out the subsequent CN coupling reaction, the methyl group on the nitrogen atom must be removed first to prepare N-demethyl nuciferine (N-Nornuciferine). Nuciferine is first reacted with m-chloroperoxybenzoic acid ( m -CPBA) to obtain the first step intermediate - nitrogen oxide of nuciferine. m -CPBA) will release a lot of heat energy during the oxidation reaction. To ensure the safety and controllability of the reaction, the reaction system needs to be cooled in advance. m A dichloromethane solution of -CPBA was slowly added dropwise to the reaction system to achieve nitrogen oxidation of nuciferine. The resulting nuciferine nitrogen oxide did not require further purification and could be used directly in subsequent reactions. Methanol and ferrous sulfate heptahydrate were added at low temperatures and the reaction was continued for 10 hours to successfully produce the demethylated product.

[0027] In this reaction, low temperature conditions are crucial because too high a temperature will lead to the formation of by-products, which will significantly reduce the yield. Through preliminary experimental exploration, it was found that under low temperature conditions of -20℃ and -10℃, the addition of m -CPBA, methanol and excess iron salt can give N-Nornuciferine in 45% yield.

[0028] Example 1 Dissolve nuciferine (2.0 g, 6.8 mmol) in 20 mL of dichloromethane solution in a 250 mL two-necked flask. Cool the entire reaction solution to -20 °C and slowly add mCPBA (1.0 g, 5.8 mmol) in dichloromethane, after stirring at low temperature for 20 min, the reaction was continued at room temperature while observing the reaction by TLC. When the starting material was converted to the intermediate product, the reaction was cooled to -20 °C again, 25 mL of methanol was added, and FeS04-7H20 (3.7 g, 13.4 mmol) was added to the reaction solution. Then, the mixture was continuously stirred at -10 °C for 40 min, moved to room temperature, and stirred for 6 h. After the starting material was completely reacted, the reaction was quenched by adding saturated sodium thiosulfate solution, filtered by suction filtration device and washed with ethyl acetate twice, then the organic phase was combined and dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and the deep green product was dissolved in a small amount of dichloromethane and added with a large amount of methanol to form a slurry. The pigment material was filtered by suction filtration device, and the filtrate was collected and concentrated under reduced pressure to obtain a deep yellow product. Silica gel column chromatography was performed with dichloromethane:methanol:ammonia water = 15:1:0.2 (volume ratio) as the mobile phase to separate and purify N-demethyllogaumine 0.9 g, yellow oil, with a yield of 45%.

[0029] II. Optimization of the conditions for preparing N-arylated logaumine derivatives 1. Ligand selection Pd(OAc)2(10 mol%) as catalyst, Johnphos, Xantphos and CataCXium A as ligands (20 mol%), demethyllogaumine (0.1 mmol) and o-methylbromobenzene (0.2 mmol) as substrates, toluene (2 mL) as solvent, t BuOK (1.5 mmol) as base, reaction at 110 °C for 12 h, no product was generated. The ligand was replaced with BINAP, and the reaction was carried out under the basic condition of BuOK. t BuOK basic condition, the results showed that two fluorescent spots with very close polarity appeared, and two of them showed coloration with potassium bismuth iodide. Therefore, under the condition of Pd(OAc)2 as catalyst, t BuOK as base, in toluene solvent, under nitrogen atmosphere, at 110 °C for 8 h, two products were separated by column chromatography and preparative silica gel plate, and the structure was analyzed subsequently. Through mass spectrometry analysis, the molecular weights of the two products were determined as 371.1885 and 369.1729, respectively.

[0030] In order to further clarify the chemical structure of the two compounds, the hydrogen nuclear magnetic resonance (1H NMR) spectrum of the two compounds was analyzed. 1The compound with a molecular weight of 371.1885 was identified as the N-o-methylbenzene derivative of nuciferine (denoted as 2a), and the compound with a molecular weight of 369.1729 was identified as Δ 6a,7 The N-o-methylbenzene derivative of nuciferine (denoted as 3a), that is, the hydrogen at the C6a position and the hydrogen at the C7 position undergo an elimination reaction, thereby forming a unique dehydronuciferine derivative with a phenanthrene ring structure.

[0031] 2. Optimization of selective reaction conditions Based on the above reaction conditions, the reaction was carried out at 90°C for 12 h. The effects of different catalysts, bases, and solvents were investigated. The results showed that each catalyst, base, and solvent affected the reaction. No product was produced using 1,4-dioxane as the solvent, while the yields of compounds 2a and 3a were very low when using DMF and THF as the reaction solvents. Furthermore, the yields of compounds 2a and 3a were also very low when using the inorganic bases Cs2CO3, K2CO3, and CsF, as well as the inorganic base NaHMDS. To further investigate the selectivity under different conditions, the yields of compounds 2a and 3a under different combinations of conditions were studied in toluene as the solvent, hoping to selectively obtain the N-o-methylbenzene derivative of nuciferine.

[0032] First, we tried to selectively modify the catalyst by re-screening it (see Table 1). Therefore, we considered screening palladium or copper catalysts in order to selectively avoid the formation of elimination products while ensuring the reaction proceeds. As shown in Table 1, in the copper-catalyzed reaction system, using CuI as catalyst, NMI as ligand, t When -BuOK is used as the base, a higher number of elimination products are selectively generated. In contrast, when CuBr is used as the catalyst, DMEDA as the ligand, and CH3ONa as the base, the reaction hardly occurs. Coupling on the secondary amine of nuciferine is also difficult when other palladium catalysts, such as PdCl2, Pd[P(ph)3]4, and (Ph3Pd)2Cl2, are used as catalysts.

[0033] Subsequently, they further explored the reaction system using Pd2(dba)3 as the catalyst and BINAP or Ph3P as the ligand, systematically screening various bases. They found that under weaker alkaline conditions, the reaction primarily produced the non-eliminated product. Although the overall conversion rate decreased, this discovery achieved a certain degree of selective control over the reaction.

[0034] During the experiment, the temperature, the strength of the base and the eq. were carefully screened. Finally, when the temperature was raised to 110 °C and tWhen -BuOK was used as the base, the reaction showed a significant characteristic, that is, almost only the elimination product was generated. It was found that the yield of the selective synthesis of N-aryl nuciferine derivatives was improved when the eq. of the base was 1.0 eq.

[0035] Table 1 Optimization of selective reaction conditions Note: a Proportion of generated products; b No product was detected; BINAP\Ph3P represents BINAP or Ph3P; NMI represents N-methylimidazole; DMEDA represents N,N'-dimethylethylenediamine.

[0036] In summary, the optimal conditions for the selective synthesis of N-aryl nuciferine derivatives are: nuciferine (1.0 eq.), aryl bromide (2.0 eq.), 10 mol% Pd2(dba)3 as catalyst, Cs2CO3 (1.0 eq.) as base, also in toluene solvent, under nitrogen protection, at 70 ℃ for 12 hours.

[0037] 3. Preparation of N-arylated nuciferine derivatives The general preparation method of the N-arylated nuciferine derivatives of the present invention is as follows: In an oxygen-free glove box, Pd2(dba)3 (9.1 mg, 10 mol%) and BINAP (12 mg, 20 mol%) were dissolved in dry toluene (2 mL) and stirred at room temperature for two hours to ensure complete dissolution and activation of the catalyst. Subsequently, under argon, demethylnuciferine (30 g, 0.1 mmol, 1.0 eq.), bromides 1a–1x (0.2 mmol, 2.0 eq.), and Cs2CO3 (48 mg, 0.10 mmol, 1.0 eq.) were added sequentially. The reaction mixture was heated to 70°C for 12 h. After completion of the reaction, the mixture was extracted with ethyl acetate, and the organic phase was collected, dried over Na2SO4, and concentrated under reduced pressure. The product was then purified by silica gel column chromatography.

[0038] Compounds 2a-2x were synthesized according to the general method described above, as follows: Example 2 Compound 2a White solid, yield 60%; 1 H NMR (600 MHz, CDCl3): d 8.4(dd,J = 7.9, 1.3 Hz, 1H),7.29(d, J = 7.3 Hz, 2H), 7.23(dd, J = 5.1, 1.6 Hz, 2H), 7.20(dd, J = 4.6, 1.5 Hz,1H), 7.17(dd, J = 7.4, 1.4, 1H), 7.12(dd, J = 7.2, 1.7 Hz, 1H), 7.07(dt, J = 7.5,1.4 Hz, 1H), 4.15(dd, J = 13.3, 4.1 Hz, 1H), 3.93(s, 3H), 3.67(s, 3H), 3.30(t, J = 10.9 Hz, 1H), 3.14–3.09(m, 1H), 3.01(td, J = 11.8, 3.4 Hz, 1H), 2.76(d, J =16.2 Hz, 1H), 2.71–2.66(m, 1H), 2.53(s, 1H), 2.39(s, 3H) ppm; 13 C NMR (150 MHz, CDCl3): d 151.98, 150.45, 145.15, 136.70, 136.15, 132.17, 130.96, 129.17,128.97, 128.35, 127.76, 127.30, 127.15, 126.88, 126.58, 124.65, 121.94,111.47, 60.24, 57.64, 55.92, 52.03, 34.98, 30.34, 17.92 ppm; HRESIMS: calcd.for CIMS 25 H 25 NO2[M + H]+: 372.1882, found: 372.1891.

[0039] Example 3 Compound 2b White solid, yield 56%; 1 H NMR (600 MHz, CDCl3): d 8.45(d, J= 8.0 Hz, 1H), 7.34(t, J = 7.6 Hz, 1H), 7.24(dd, J = 7.3, 1.2 Hz, 1H), 7.21(d, J = 7.4 Hz, 1H), 6.71(d, J = 9.7 Hz, 3H), 6.62(s, 1H), 4.36(dd, J = 13.7, 3.7 Hz, 1H), 3.92(d, J = 0.8Hz, 3H), 3.68(d, J = 1.1 Hz, 3H), 3.60(ddd, J = 11.9, 6.9, 4.3 Hz, 1H), 3.31(ddd, J = 12.0, 7.0, 4.2 Hz, 1H), 3.02–2.97(m, 1H), 2.93(dd, J = 14.4, 3.8 Hz, 2H),2.69(t, J = 14.0 Hz, 1H), 2.31(s, 6H) ppm; 13 C NMR (150 MHz, CDCl3): d 152.37,148.86, 145.38, 138.78, 137.17, 132.15, 129.58, 129.24, 128.45, 127.96,127.47, 127.35, 126.95, 122.49, 116.76, 111.47, 77.32, 77.00, 76.68, 60.11,55.92, 46.87, 34.25, 30.15, 21.61 ppm; HRESIMS: calcd. for C 26 H 27 NO2[M + H] + :386.2044, found:386.2052.

[0040] Example 4 Compound 2c White solid, yield 70%; 1 H NMR (600 MHz, CDCl3): d 8.53(d, J= 7.2 Hz, 1H), 8.42(d, J = 7.8 Hz, 1H), 7.89(d, J = 9.5 Hz, 1H), 7.71(d, J = 8.1 Hz, 1H), 7.53–7.50(m,2H), 7.49(t, J = 7.8 Hz, 1H), 7.40(d, J = 7.4 Hz, 1H), 7.33–7.30(m, 1H), 7.17(td, J = 7.4, 1.3 Hz, 1H), 7.02(d, J = 7.4 Hz, 1H), 6.79(s, 1H), 4.33(d, J = 13.5 Hz,1H), 3.96(s, 3H), 3.70(s, 3H), 3.49(d, J = 13.1 Hz, 1H), 3.37(dd, J = 12.2, 5.8Hz, 1H), 3.15(t, J = 11.8 Hz, 1H), 2.83(d, J = 17.0 Hz, 1H), 2.72(d, J = 10.3 Hz,1H), 2.60(t, J = 13.8 Hz, 1H) ppm; 13 C NMR(150 MHz, CDCl3): d 152.08, 148.63,145.24, 136.67, 134.79, 132.15, 131.94, 129.11, 128.92, 128.36, 128.07,127.75, 127.32, 127.24, 126.90, 126.05, 125.79, 125.72, 124.92, 123.78,118.30, 111.53, 60.27, 58.04, 55.95, 52.99, 34.99, 30.44 ppm;HRESIMS:calcd.for C 28 H 25 NO2[M + H] + :408.1905, found:408.1911。

[0041] 实施例5化合物2d White solid, yield 62%; 1 H NMR (600 MHz, CDCl3): d 8.46(d, J = 8.1 Hz, 1H), 7.77(t, J = 9.4 Hz, 2H), 7.71(d, J = 8.2 Hz, 1H), 7.43(t, J = 7.5 Hz, 1H), 7.37–7.31(m,4H), 7.24(d, J = 7.4 Hz, 1H), 7.19(d, J = 7.5 Hz, 1H), 6.75(s, 1H), 4.56(d, J =12.0 Hz, 1H), 3.94(s, 3H), 3.77–3.73(m, 1H), 3.70(d, J = 1.9 Hz, 3H), 3.45(s,1H), 3.05(d, J = 16.3 Hz, 1H), 3.00–2.96(m, 2H), 2.75(t, J = 13.7 Hz, 1H) ppm; 13 CNMR (150 MHz, CDCl3): d 152.04, 147.91, 145.42, 137.01, 134.62, 132.11, 129.50,128.91, 128.79, 128.50, 128.00, 127.83, 127.54, 127.45, 127.03, 126.71,126.22, 125.28, 123.46, 120.65, 113.25, 111.47, 60.12, 55.94, 55.90, 46.38,34.29, 30.16 ppm; HRESIMS: calcd. for C 28 H 25 NO2[M + H] + :408.1905, found:408.1911.

[0042] Example 6 Compound 2e White solid, yield 65%; 1H NMR (600 MHz, CDCl3): d 8.39(d, J = 7.9 Hz, 1H), 7.30(t, J = 7.6 Hz, 1H), 7.19(s, 1H), 7.14(d, J = 8.5 Hz, 2H), 7.11(d, J = 7.5 Hz, 1H),6.90(d, J = 8.7 Hz, 2H), 6.71(s, 1H), 4.03(dd, J = 13.8, 3.9 Hz, 1H), 3.91(s,3H), 3.82(s, 3H), 3.67(s, 3H), 3.28(dt, J = 8.7, 3.0 Hz, 2H), 3.23–3.18(m, 1H), 2.84–2.80(m, 1H), 2.74(dd, J = 14.1, 4.0 Hz, 1H), 2.61(t, J = 13.8 Hz, 1H) ppm; 13 CNMR (150 MHz, CDCl3): d 156.03, 152.03, 145.28, 136.64, 132.16, 129.07, 128.33,127.86, 127.32, 127.16, 126.91, 124.24, 114.39, 111.50, 60.21, 58.28, 55.92,55.49, 51.40, 35.06, 30.21 ppm; HRESIMS: calcd. for C 25 H 25 NO3[M + H] + :388.1839,found:388.1844.

[0043] Example 7 Compound 2f White solid, yield 60%; 1 H NMR (600 MHz, CDCl3): δ 8.40 (d, J = 8.0 Hz, 1H), 7.32(t, J = 7.7 Hz, 1H), 7.21(t, J= 7.5 Hz, 1H), 7.13(d, J = 7.5 Hz, 1H), 7.09(dd, J =8.9, 4.7 Hz, 2H), 7.03(d, J = 8.5 Hz, 2H), 6.71(s, 1H), 4.13(dd, J = 13.7, 3.8Hz, 1H), 3.92(s, 3H), 3.67(s, 3H), 3.40–3.36(m, 1H), 3.29(dt, J = 11.5, 4.9 Hz,1H), 3.15–3.10(m, 1H), 2.86(dd, J = 15.9, 4.5 Hz, 1H), 2.75(dd, J = 14.1, 3.9 Hz,1H), 2.63(t, J = 13.8 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 159.39\157.79( J CF = 240Hz), 152.07, 147.34\147.32( J CF = 3 Hz), 145.32, 136.58, 132.09, 129.13, 128.41,128.00, 127.88, 127.43, 127.24, 127.02, 122.97, 122.91, 115.79, 115.64,111.45, 60.19, 57.54, 55.92, 49.72, 34.74, 30.13 ppm; HRESIMS: calcd. forC 24 H 22 FNO2[M + H] + :376.1635, found:376.1650.

[0044] Example 8 Compound 2g White solid, yield 72%; 1 H NMR (600 MHz, CDCl3): d 8.45 (dd, J= 7.8, 1.2 Hz,1H), 7.37–7.34 (m, 1H), 7.29–7.26 (m, 1H), 7.25 (s, 1H), 7.23–7.19 (m, 1H),6.71 (q, J = 3.0, 2.3 Hz, 2H), 6.64 (dt, J = 12.5, 2.4 Hz, 1H), 6.52 (td, J = 8.3,2.4 Hz, 1H), 4.45 (dd, J = 13.8, 3.6 Hz, 1H), 3.92 (s, 3H), 3.81–3.78 (m, 1H),3.68 (s, 3H), 3.29 (ddd, J = 12.7, 9.5, 3.4 Hz, 1H), 2.97–2.92 (m, 2H), 2.88–2.84 (m, 1H), 2.76 (t, J = 13.9 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 164.89\163.28 ( J CF = 242 Hz), 152.08, 151.17\151.10 ( J CF = 11 Hz), 145.50, 136.81,131.97, 130.29\130.22 ( J CF = 11 Hz), 129.59, 128.54, 128.08, 127.65, 127.51,127.30, 127.13, 111.56\111.55 ( J CF = 2 Hz), 111.44, 105.17\105.02 ( J CF = 23 Hz),103.03\102.86 ( J CF = 26 Hz), 60.09, 55.95, 55.18, 43.78, 33.66, 29.89 ppm;HRESIMS:calcd. for C 24 H 20 FNO2[M + H] +:376.4314, found:376.4322.

[0045] Example 9 Compound 2h White solid, yield 45%; 1 H NMR (600 MHz, CDCl3): δ 8.45(d, J = 7.9 Hz, 1H), 7.59(d, J = 6.8 Hz, 2H), 7.55(d, J = 8.2 Hz, 2H), 7.42(t, J = 7.6 Hz, 2H), 7.36–7.33(m,1H), 7.29(t, J = 7.4 Hz, 1H), 7.25(d, J = 6.8 Hz, 2H), 7.07(d, J = 8.2 Hz, 2H), 6.72(s, 1H), 4.47(dd, J = 13.6, 3.6 Hz, 1H), 3.93(s, 3H), 3.77(dd, J = 11.2, 6.2Hz, 1H), 3.69(s, 3H), 3.36(dt, J = 12.3, 6.0 Hz, 1H), 3.00(dd, J = 14.1, 3.7 Hz,1H), 2.95(t, J = 5.4 Hz, 2H), 2.75(t, J = 13.9 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 151.01, 147.76, 142.09, 132.27, 129.50, 129.28, 128.72, 128.55,128.06, 127.91, 127.69, 127.59, 126.76, 126.51, 126.45, 125.32, 124.36,123.16, 117.62, 111.72, 111.49, 105.35, 60.15, 59.81, 56.47, 55.98, 48.59,31.46 ppm; HRESIMS: calcd. for C 30 H 27NO2[M + H] + :4334.2020, found:434.2035.

[0046] Example 10 Compound 2i White solid, yield 52%; 1 H NMR (600 MHz, CDCl3): d 8.53(d, J = 5.7 Hz, 1H), 8.41(d, J = 8.1 Hz, 1H), 8.34–8.28(m, 1H), 7.56–7.50(m, 2H), 7.33–7.28(m, 2H), 7.15(t, J = 7.4 Hz, 1H), 7.00(d, J = 7.4 Hz, 1H), 6.81(d, J = 8.1 Hz, 1H), 6.78(s, 1H), 4.22(d, J = 12.0 Hz, 1H), 4.03(s, 3H), 3.96(s, 3H), 3.69(d, J = 1.8 Hz, 3H),3.49–3.42(m, 1H), 3.27(dd, J = 12.0, 5.9 Hz, 1H), 3.18–3.10(m, 1H), 2.81(d, J =15.8 Hz, 1H), 2.65(dd, J = 14.1, 4.1 Hz, 1H), 2.58(t, J = 13.7 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 152.89, 152.04, 145.19, 136.83, 133.00, 132.20, 129.21,128.33, 127.77, 127.25, 127.19, 126.83, 126.37, 126.28, 125.45, 123.59,122.03, 118.29, 111.55, 103.53, 60.27, 58.80, 55.96, 55.58, 53.06, 35.09,30.62 ppm; HRESIMS: calcd. for C29 H 27 NO3[M + H] + :438.2087, found:438.2106.

[0047] Example 11 Compound 2J White solid, yield 61%; 1H NMR (600 MHz, CDCl3): d 8.45(d, J = 7.9 Hz, 1H), 7.37–7.34(m, 1H), 7.28(s, 1H), 7.26(s, 1H), 7.26(d, J = 5.7 Hz, 1H), 7.21(d, J = 7.2Hz, 1H), 6.96(d, J = 8.9 Hz, 2H), 6.73(s, 1H), 4.35(dd, J = 13.7, 3.7 Hz, 1H),3.63(ddd, J = 12.2, 6.0, 4.3 Hz, 1H), 3.31(ddd, J = 12.0, 7.6, 4.1 Hz, 1H), 3.00–2.96(m, 1H), 2.93(dd, J = 7.5, 4.4 Hz, 1H), 2.88(dd, J = 14.1, 3.7 Hz, 1H), 2.71(t, J = 13.8 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 152.11, 148.70, 145.47,136.74, 132.05, 129.38, 129.17, 128.53, 127.99, 127.59, 127.43, 127.12,124.96, 119.46, 111.47, 60.15, 55.97, 55.89, 46.06, 34.04, 30.01 ppm; HRESIMS: calcd. for C 25 H 30 N2O [M + H]+: 392.1339, found: 392.1350.

[0048] Example 12 Compound 2k 白色固体,收率66%; 1 H NMR(600 MHz, CDCl3): d 8.45(d, J = 7.9 Hz, 1H), 7.35(t, J = 7.0 Hz, 1H), 7.28–7.26(m, 1H), 7.24(dd, J = 7.3, 1.5 Hz, 1H), 7.13(t, J =8.1 Hz, 1H), 7.10(t, J = 2.0 Hz, 1H), 6.96(dd, J = 7.7, 1.8 Hz, 1H), 6.88(dd, J =8.3, 2.4 Hz, 1H), 6.71(s, 1H), 4.43(dd, J = 13.8, 3.6 Hz, 1H), 3.92(s, 3H),3.75(dt, J = 12.4, 4.5 Hz, 1H), 3.68(s, 3H), 3.29(ddd, J = 12.5, 8.9, 3.7 Hz,1H), 2.92(dt, J = 10.4, 2.8 Hz, 2H), 2.88(dt, J = 15.4, 4.2 Hz, 1H), 2.74(t, J =13.9 Hz, 1H) ppm; 13 C NMR(150 MHz, CDCl3): d 152.08, 150 .85, 145.48, 136.72,131.96, 130.46, 129.49, 128.52, 128.06, 127.66, 127.45, 127.24, 127.12,123.37, 121.76, 119.38, 115.19, 111.43, 60.08, 55.93, 55.20, 44.20, 33.73,29.90 ppm;HRESIMS:calcd. for C 24 H 22 BrNO2[M + H] + :436.0834, found:436.0844。

[0049] Example 13 Compound 21 White solid, yield 51.7%; 1 H NMR (600 MHz, CDCl3): d 7.40(d, J = 9.2 Hz, 1H), 6.61(d, J = 8.8 Hz, 2H), 6.32(d, J = 9.6 Hz, 1H), 6.27(d, J = 8.8 Hz, 2H), 5.50(d, J = 4.4 Hz, 1H), 5.46(q, J = 6.8 Hz, 1H), 3.71(s, 3H), 3.67(s, 1H), 3.03(dd, J = 15.6, 4.4 Hz, 1H), 2.80(dd, J = 16.8, 2.0 Hz, 1H), 2.38(d, J = 15.6 Hz, 1H), 2.20(d, J = 16.0 Hz, 1H), 1.63(d, J = 6.8 Hz, 3H), 1.60(s, 3H) ppm; 13 C NMR (150 MHz, CDCl3): d 152.10, 148.94, 145.48, 136.72, 132.07, 132.01, 129.39, 128.5 2,127.98, 127.60, 127.43, 127.12, 126.69119.38, 111.89, 111.46, 60.12, 55.95,55.60, 45.44, 33.90, 29.96 ppm; HRESIMS: calcd. for C 24 H 22 BrNO2[M + H] + :436.0834,found:436.0844.

[0050] Example 14 Compound 2m White solid, yield 43%; 1 H NMR (600 MHz, CDCl3): d8.43(d, J = 8.0 Hz, 1H), 7.34(d, J = 7.5 Hz, 1H), 7.23(d, J = 7.3 Hz, 1H), 7.20(d, J = 7.4 Hz, 1H), 7.05(d, J =8.1 Hz, 2H), 6.93(t, J = 7.3 Hz, 1H), 6.71(s, 1H), 4.38(dd, J = 13.7, 3.7 Hz,1H), 3.92(s, 3H), 3.68(s, 3H), 3.66–3.63(m, 1H), 3.33(td, J = 7.6, 3.7 Hz, 1H),3.01–2.97(m, 1H), 2.91(dd, J = 14.2, 3.9 Hz, 2H), 2.70(t, J = 13.9 Hz, 1H) ppm; 13 CNMR (100MHz, CDCl3): 150.20, 145.41, 137.00, 132.12, 129.26, 128.49, 127.99, 127.50, 127.01, 120.28, 118.53, 111.49, 60.14, 55.96, 46.35, 34.19, 31.93,30.11 ppm; HRESIMS: calcd. for C 25 H 23 NO4[M + H] + :402.1647, found:402.1659.

[0051] Example 15 Compound 2n White solid, yield 63%; 1 H NMR (600 MHz, CDCl3): d 8.45(d, J = 7.9 Hz, 1H), 7.36(d, J = 7.5 Hz, 1H), 7.34–7.31(m, 2H), 7.26(td, J = 7.3, 1.3 Hz, 1H), 7.22(d, J=7.4 Hz, 1H), 7.07(d, J = 8.0 Hz, 2H), 6.95(t, J = 7.3 Hz, 1H), 6.74(s, 1H), 4.40(dd, J = 13.6, 3.7 Hz, 1H), 3.94(s, 3H), 3.70(s, 3H), 3.68–3.65(m, 1H), 3.35(ddd, J = 11.9, 7.3, 4.1 Hz, 1H), 3.01(ddd, J = 15.6, 6.5, 4.3 Hz, 1H), 2.96–2.91(m, 2H), 2.72(t, J = 13.9 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): 152.01, 150.19,145.41, 136.99, 132.11, 129.56, 129.25, 128.48, 127.98, 127.49, 127.43,127.00, 120.27, 118.52, 111.49, 60.13, 55.96, 55.90, 46.34, 34.18, 30.10 ppm; HRESIMS: calcd. for C 24 H 23 NO2[M + H] + :358.1729, found:358.1733.

[0052] Example 16 Compound 2o White solid, yield 75%; 1 H NMR (600 MHz, CDCl3): d 8.47(d, J = 8.0 Hz, 1H), 7.39–7.35(m, 2H), 7.29–7.27(m, 1H), 7.24(d, J = 7.5 Hz, 1H), 7.18(s, 1H), 7.10(dd, J =14.1, 8.4 Hz, 2H), 6.73(s, 1H), 4.52–4.49(m, 1H), 3.93(s, 3H), 3.83(dt, J=12.3, 4.6 Hz, 1H), 3.70(d, J = 1.5 Hz, 3H), 3.34(ddd, J = 12.6, 8.9, 3.8 Hz, 1H),2.99–2.95(m, 1H), 2.94–2.93(m, 1H), 2.91(d, J = 11.4 Hz, 1H), 2.76(t, J = 13.9 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 52.15, 149.64, 145.54, 136.60, 131.95,131.79, 131.47, 129.70, 129.41, 128.54, 127.99, 127.72, 127.47, 127.18,125.69, 122.98, 119.46, 115.24, 112.76, 111.44, 60.09, 55.93, 55.12, 44.14,33.66, 29.90 ppm; HRESIMS: calcd. for CIMS 25 H 22 F3NO2[M + H] + :426.1603, found:426.1610.

[0053] Example 17 Compound 2p White solid, yield 80%; 1 H NMR (600 MHz, CDCl3): d 8.48(d, J = 7.5 Hz, 1H), 7.49(d, J = 8.6 Hz, 2H), 7.39–7.36(m, 1H), 7.31–7.29(m, 1H), 7.28(d, J = 1.0 Hz, 1H),6.92(d, J = 8.5 Hz, 2H), 6.73(s, 1H), 4.60(dd, J = 13.8, 3.6 Hz, 1H), 4.01(ddd, J=12.7, 4.4, 3.2 Hz, 1H), 3.93(s, 3H), 3.70(s, 3H), 3.31(ddd, J = 13.1, 10.9, 2.8Hz, 1H), 2.96(td, J = 13.9, 13.4, 4.1 Hz, 2H), 2.84–2.79(m, 2H) ppm; 13 C NMR (150MHz, CDCl3): d 152.17, 150.97, 145.62, 136.60, 131.90, 129.55, 128.61, 128.09,127.76, 127.53, 127.25, 126.81, 126.65, 126.63, 126.60, 126.58, 125.78,123.99, 113.58, 111.44, 60.07, 55.94, 54.38, 41.97, 33.27, 29.80 ppm; HRESIMS: calcd. for C 25 H 22 F3NO2[M + H] + :347.2102, found:347.2123.

[0054] Example 18 Compound 2q White solid, yield 40%; 1 H NMR (600 MHz, CDCl3): d 8.43(d, J = 8.1 Hz, 1H), 8.37(d, J = 2.9 Hz, 1H), 8.12(dd, J = 4.5, 1.4 Hz, 1H), 7.34(t, J = 8.1 Hz, 1H), 7.26–7.23(m, 2H), 7.22–7.18(m, 2H), 6.71(s, 1H), 4.43(dd, J = 13.7, 3.7 Hz, 1H),3.92(s, 3H), 3.77(dt, J = 12.4, 4.8 Hz, 1H), 3.68(s, 3H), 3.32(dt, J= 12.4, 6.1Hz, 1H), 2.93(t, J = 5.5 Hz, 2H), 2.89(dd, J = 14.1, 3.7 Hz, 1H), 2.75(t, J = 13.9 Hz, 1H) ppm; 13 C NMR (150 MHz, CDCl3): d 152.16, 145.54, 145.51, 140.35, 139.71,136.40, 131.91, 129.31, 128.52, 128.04, 127.66, 127.45, 127.19, 126.99,123.68, 123.53, 111.45, 60.10, 55.93, 55.12, 44.47, 33.84, 29.83 ppm; HRESIMS: calcd. for C 23 H 22 N2O2[M + H] + :358.1737, found:358.1760.

[0055] Example 19 Compound 2r White solid, yield 30%; 1 H NMR (600 MHz, CDCl3): d 8.48(dd, J = 7.9, 1.2 Hz, 1H),8.21–8.18(m, 1H), 7.46(td, J = 8.7, 7.9, 2.0 Hz, 1H), 7.36(td, J = 7.4, 1.9 Hz,1H), 7.32–7.29(m, 1H), 7.28(dd, J = 7.1, 1.3 Hz, 1H), 6.72(s, 1H), 6.56(dd, J =7.5, 5.1 Hz, 2H), 5.02(ddd, J = 12.8, 4.6, 2.1 Hz, 1H), 4.74(dd, J = 13.8, 3.7Hz, 1H), 3.92(s, 3H), 3.68(s, 3H), 3.13–3.09(m, 1H), 3.00(dd, J= 14.0, 3.8 Hz,1H), 2.95–2.90(m, 1H), 2.90–2.85(m, 1H), 2.74(dt, J = 15.3, 2.4 Hz, 1H) ppm; 13 CNMR (150 MHz, CDCl3): d 152.03, 145.54, 132.01, 130.50, 128.62, 128.21, 127.66,127.59, 127.12, 111.97, 111.61, 60.05, 55.96, 52.66, 33.32, 30.13, 29.68 ppm; HRESIMS: calcd. for C 23 H 20 F6N2O [M + H] + :358.1737, found:358.1760.

[0056] Example 20 Compound 2s White solid, yield 80%; 1 H NMR (600 MHz, CDCl3): d 8.47(d, J = 7.7 Hz, 1H), 7.95(d, J = 3.1 Hz, 1H), 7.35(ddt, J = 7.9, 5.7, 1.7 Hz, 1H), 7.29–7.27(m, 2H), 7.16(dd, J = 9.1, 3.1 Hz, 1H), 6.72(s, 1H), 6.57(d, J = 9.1 Hz, 1H), 4.75(ddd, J =12.7, 4.5, 2.7 Hz, 1H), 4.68(dd, J = 13.7, 3.7 Hz, 1H), 3.91(s, 3H), 3.80(s,3H), 3.68(s, 3H), 3.16–3.12(m, 1H), 2.96(dd, J = 14.0, 3.8 Hz, 1H), 2.94–2.89(m, 1H), 2.84(t, J = 13.8 Hz, 1H), 2.77–2.74(m, 1H) ppm;13 C NMR (150 MHz, CDCl3): d 153.06, 151.93, 148.22, 145.42, 137.18, 133.56, 132.03, 130.43, 128.55,128.16, 127.56, 127.32, 127.01, 125.42, 111.57, 107.73, 60.02, 56.47, 55.92,53.18, 39.16, 33.56 ppm; HRESIMS: calcd. for C 24 H 28 N2O2[M + H] + :389.1787, found:389.1788.

[0057] Example 21 Compound 2t White solid, yield 75%; 1 H NMR (600 MHz, CDCl3): d 8.48(d, J = 7.6 Hz, 1H), 7.40(d, J = 7.9 Hz, 1H), 7.36–7.34(m, 1H), 7.30–7.27(m, 2H), 6.72(s, 1H), 6.12(d, J =8.1 Hz, 1H), 6.02(d, J = 7.8 Hz, 1H), 4.85–4.81(m, 2H), 3.92(s, 3H), 3.85(s,3H), 3.69(s, 3H), 3.14(dd, J = 12.4, 2.5 Hz, 1H), 3.10–3.08(m, 1H), 2.94–2.90(m, 1H), 2.84(t, J = 13.8 Hz, 1H), 2.73(dt, J = 15.2, 2.4 Hz, 1H) ppm; 13 C NMR (150MHz, CDCl3): d163.15, 156.18, 151.95, 145.56, 140.06, 137.30, 132.00, 130.29,128.57, 128.05, 127.64, 127.62, 127.29, 127.01, 111.53, 97.51, 96.34, 60.06,55.96, 52.92, 52.54, 38.42, 33.45 ppm; HRESIMS: calcd. for C 25 H 24 N2O [M + H] + :389.1787, found:389.1788.

[0058] Example 22 Compound 2x White solid, yield 60%; 1 H NMR (600 MHz, CDCl3): d 8.51 (d, J = 7.9 Hz,1H), 7.89(d, J = 9.1 Hz,1H), 7.71 (d, J = 8.4 Hz,1H), 7.60 (dd, J = 7.9,1.4 Hz,1H), 7.54(ddd, J = 8.4, 6.7, 1.5 Hz, 1H), 7.38 (td, J = 7.9, 7.3, 2.3 Hz, 1H), 7.31 (t, J =4.4 Hz, 2H), 7.21 (t, J = 7.4 Hz, 1H), 6.94 (d, J = 9.2 Hz, 1H), 6.75 (s, 1H), 5.33 (d, J = 13.0 Hz, 1H), 4.97 (dd, J = 13.7, 3.9 Hz, 1H), 3.93 (s, 3H), 3.70(s, 3H), 3.19 (td, J = 12.5, 2.5 Hz, 1H), 3.04 (dd, J = 14.0, 3.9 Hz, 1H), 2.95(dd, J= 16.1, 12.0 Hz, 2H), 2.80 (d, J = 15.4 Hz, 1H)ppm; 13 C NMR (150 MHz, CDCl3): d 155.71, 152.03, 148.06, 145.51, 137.49, 136.92, 131.98, 130.50, 129.51,128.63, 128.20, 127.70, 127.58, 127.20, 127.1, 126.80, 126.38, 122.81,121.93, 111.51, 109.56, 60.06, 55.93, 52.54, 38.14, 34.12, 30.31 ppm; HRESIMS: calcd. for C 27 H 24 N2O2[M + H] + :409.1838, found:409.1815.

[0059] IV. Evaluation of lipid-lowering activity of N-arylated nuciferine derivatives To systematically evaluate the lipid-lowering activity of N-arylated nuciferine derivatives, their inhibitory efficiency against pancreatic lipase was quantitatively analyzed. Molecular docking techniques were used to elucidate the binding pattern between the active molecules and the lipase active site, with a focus on predicting key hydrogen bonding and hydrophobic interactions. Secondly, the inhibitory effect of the derivatives on lipid accumulation was evaluated by analyzing the inhibition rate of lipid droplet formation using Oil Red O staining in a 3T3-L1 preadipocyte differentiation model. Furthermore, cell proliferation activity was assessed using the MTT assay to verify the concentration range of the target compounds' lipid-lowering activity. This provides innovative experimental evidence for the study of the structure-activity relationship of nuciferine derivatives and the exploration of their lipid-lowering mechanisms.

[0060] 1. In vitro lipase activity inhibition test Lipase activity is an important indicator for evaluating the anti-obesity efficacy of drugs. Therefore, the lipase inhibitory ability of N-nuciferine derivatives was determined. A preliminary screening of these derivatives was conducted at a concentration of 200 μM, using orlistat as a positive control. The results are as follows:

[0061] The lipase enzyme was dissolved in 0.1 mol / L phosphate buffer (pH 7.4) to make a solution with a concentration of 0.71 mg / mL and stored at 4°C for later use. Then, the inhibitors (Nuciferine and its derivatives) were dissolved in DMSO to prepare a series of inhibitor solutions with different concentrations, while ensuring that the concentration of DMSO in the final solution was maintained at 3.0%. Then, they were immediately mixed with the lipase solution and reacted for 10 min at a constant temperature of 37°C before adding 0.5 mmol / L p-NPP (p-nitrophenyl palmitate) solution. After the start of the reaction, the absorbance value was measured at a wavelength of 420 nm using a spectrophotometer, denoted as A 0 . After waiting for 15 minutes for the reaction to proceed, the absorbance value was measured again, denoted as A t . To obtain accurate enzyme activity data, it is necessary to additionally measure the absorbance before and after the reaction without the sample solution as a control, and the entire experiment should be performed in triplicate to ensure the repeatability and accuracy of the data. The calculation formula is as follows.

[0062] Inhibition rate% In the formula, △A1: the difference in absorbance before and after the reaction with different concentrations of sample solution (A t - A 0 ); △A2: the difference in absorbance before and after the reaction without sample solution (A t - A 0 ); A 0 : the initial absorbance value of the reaction; A t : the absorbance value after 15 min of reaction.

[0063] As shown in Table 2, the results indicate that most N-arylated nuciferine derivatives exhibited significant lipase inhibition. In particular, compounds (2c) N-1-naphthylnuciferine, (2h) N-biphenyl-4-nuciferine, (2i) N-4-methoxynaphthalene-1-nuciferine, (2n) N-phenyl-nuciferine, and (2s) N-5-methoxypyridine-2-nuciferine exhibited excellent activity, with lipase inhibition comparable to or even superior to that of nuciferine. Compound 2n exhibited the most outstanding activity, achieving an 80% inhibition rate against lipase at a concentration of 200 μM. Therefore, it can be seen that the substituents on the aromatic ring have a significant effect on the anti-lipase activity of nuciferine analogs. Specifically, the introduction of phenyl, biphenyl, or electron-donating substituents (such as methoxy) onto the benzene ring significantly enhances the lipase inhibitory activity of nuciferine. For example, compounds 2c and 2i, which contain naphthalene or methoxynaphthalene ring modifications, exhibit significantly enhanced activity compared to nuciferine. Conversely, the introduction of electron-withdrawing groups (fluorine and trifluoromethyl) onto the benzene ring somewhat reduces their lipase inhibitory activity (2f, 2g). Furthermore, the introduction of heterocyclic rings such as pyridine and quinoline also reduces the lipase inhibitory activity of nuciferine (2q, 2x).

[0064] Table 2 Inhibitory activity of N-arylated nuciferine derivatives against pancreatic lipase Note: Nuc stands for Nuciferine, which has the same meaning in subsequent experiments and is not repeated here; Orlistat stands for Orlistat; [I] stands for the concentration of the derivative.

[0065] In order to further explore the potential anti-lipase efficacy of the modified compounds, the compounds that showed significant inhibitory effects on lipase activity in Table 2 were selected to further accurately determine the IC values ​​of these compounds against lipase. 50 The results are shown in Table 3 below. The results show that derivative 2n is the most significant compound for anti-lipase activity. 50 The value was 0.0551±0.005mg / mL. The potency of the uneliminated derivative compounds measured reached that of nuciferine (IC 50 : 0.208±0.02).

[0066] Table 3 IC of preferred derivatives 50 Note: a Lipase from porcine pancreas; IC 50 The lipase half-maximal inhibitory concentration is shown (mean ± SD of three experiments).

[0067] 2. In vitro cell proliferation activity assay of 3T3-L1 cell line 3T3-L1 preadipocytes were pretreated with 20 μM of the test compound, and the cell viability was measured for subsequent lipid-lowering activity evaluation as follows: (1) Cell recovery: Preparation: Preheat a water bath to 37°C, preheat complete culture medium for 3T3-L1 cells, quickly thaw cells frozen in liquid nitrogen or at -80°C, and shake to thaw in a 37°C water bath for 1-2 minutes. Transfer the suspension to a centrifuge tube containing preheated culture medium, add 2 mL of culture medium, centrifuge at low speed (800-1000 rpm, 5 minutes), and discard the supernatant. Resuspend the cells in 1 mL of culture medium and gently pipette to mix. Inoculate into a culture flask containing 4-5 mL of culture medium and adjust the density. Culture in a 37°C, 5% CO2 incubator, change the medium the next day, and continue culturing until the cells recover to normal before passage.

[0068] (2) Cell passaging: When the cells in the culture flask grow to about 80-90%, the passaging operation can be carried out. Preparation: Ensure a sterile operating environment, place the required sterile culture flasks, centrifuge tubes, pipettes, etc. in the clean bench, and irradiate with ultraviolet light for 30 minutes for disinfection. Observe the cell morphology and density under an inverted microscope. When the cells reach the appropriate passaging condition, the passaging experiment can be started. Digestion of cells (for adherent cells) Disinfect the mouth of the culture flask with 75% alcohol and remove the old culture medium. Wash the cells with PBS buffer to remove the residual culture medium. After addition, add trypsin containing 25% EDTA to digest the cells for 1-2 minutes (digestion time depends on the cell type). Usually, digestion is stopped when the cells become round and the gaps between them increase under the microscope. Add fresh culture medium containing serum to stop digestion and gently blow the cells to suspend them. Centrifuge the cell suspension at 1000 rpm for 5 minutes. Remove the supernatant and retain the cell pellet. Add an appropriate amount of complete culture medium 4-5 mL to the cell pellet and mix it by blowing to ensure that the cells are evenly dispersed. Based on the experimental requirements, divide the cell suspension into new culture flasks in appropriate proportions, add fresh culture medium, and label with the cell name, passage number, date, and operator. Return the culture flasks to the CO2 incubator and set the appropriate temperature, humidity, and CO2 concentration.

[0069] (3) Cell proliferation activity assay: The MTT assay was used to assay the in vitro cell proliferation activity of the compounds. 3T3-L1 cells were cultured in a 37°C, 5% CO2 incubator using a dedicated culture medium until the logarithmic growth phase. The test compound was diluted to 50 μM with DMSO and then used for further dilution. 5×10³ cells / well were seeded into a 96-well plate (100 μL / well). The test group: added the test sample (20 μM, 100 μL), the blank group: added blank culture medium (100 μL), and the control group: added culture medium containing 1‰ DMSO (100 μL). Each group had 3 replicates. After 24 h of incubation, 20 μL (5 mg / mL MTT solution) was added to each well and the culture was continued for 4 h. The supernatant was discarded, 150 μL DMSO / well was added, and the mixture was shaken for 10 min. The absorbance at 492 nm was measured using a microplate reader.

[0070] As shown in Table 4, the in vitro antiproliferative activity of compounds 2a~2v on 3T3-L1 preadipocytes was evaluated. As shown in Table 4, most compounds showed low toxicity at 20 μM, demonstrating that the compounds did not cause significant damage to 3T3-L1 preadipocytes, ensuring the normal progress of subsequent lipid-lowering activity experiments.

[0071] Table 4 Proliferation activity of compounds 2a~2v at 20 μM on 3T3-L1 cells 3. In vitro lipid-lowering activity assay of 3T3-L1 preadipocyte cell line After preliminary proliferation activity screening, compounds with less cell inhibitory activity were selected for in vitro lipid accumulation activity assay in 3T3-L1 preadipocytes, as follows: (1) Preparation of 3T3-L1 (mouse embryonic fibroblast) adipogenic differentiation medium: Thaw the serum at 4°C until completely thawed; Thaw each additive at room temperature until completely thawed, and gently shake A ① , B mix; A ② Centrifuge briefly to collect all the reagents at the bottom of the tube. ① 、A ② Add to basal medium A in sequence; mix thoroughly, label, and use. Solution B preparation: Add FBS (two FBS bottles are the same) and B to basal medium B in sequence, mix thoroughly, label, and use.

[0072] (2) Cell adipogenic differentiation: When the cell confluence reaches 80-90%, digest with 0.25% trypsin and count. The cell count is 2-3×10 4 cells / cm 2Cells were seeded at a high density into 24-well plates (2 mL of complete medium per well) and incubated at 37°C, 5% CO2. When confluency reached 100%, the complete medium was aspirated and 2 mL of a mixture of 20 μM derivative compound and Induction Medium A was added. Induction was continued for 2-3 days. The culture medium was then switched to 2 mL of Induction Medium B alone for 1 day. After 3-5 cycles of alternating induction with Medium A and Medium B, when sufficient lipid droplets were observed, the cells were cultured in Medium B for another 3-6 days until the lipid droplets became sufficiently large and plump. Induction was terminated, and the cells were then stained and subsequently identified.

[0073] (3) Oil Red O staining: After the adipogenic induction experiment, remove the induction medium and rinse with 1× PBS 1-2 times. Add 4% neutral formaldehyde to fix the cells for 30 minutes. During the fixation period, prepare Oil Red O working solution (saturated Oil Red O: distilled water = 3:2, filtered to remove impurities). Remove the aldehyde fixation solution and rinse with 1× PBS 1-2 times. Add 1 mL of Oil Red O working solution to each well and stain at room temperature for 30 minutes. Taking a six-well plate as an example, add 1 mL of Oil Red O working solution to each well and stain at room temperature for 30 minutes. Remove the Oil Red O working solution and rinse with 1× PBS 1-2 times to clean the background impurities. Then observe the induction and staining effects under a microscope.

[0074] like Figure 1 and Figure 2 (CG in the figure represents blank control) As shown, through the analysis of experimental results, when the cells were treated with 20 μM N-arylated nuciferine derivatives for 7 days, N-arylated nuciferine derivatives 2k, 2l, 2e, 2g, 2m, 2i and 2o all showed inhibitory effects on lipid accumulation during differentiation in 3T3-L1 preadipocytes to varying degrees, especially compounds 2i and 2o showed better lipid accumulation inhibitory effects.

[0075] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. An N-aryl nuciferine derivative, characterized in that The chemical structure of the N-aryl nuciferine derivative is shown in Formula I: In formula I, the aromatic ring A is selected from a benzene ring, a naphthalene ring, a biphenyl ring or a nitrogen aromatic heterocycle; R is selected from an electron-donating group, an electron-withdrawing group, or both ends are connected to the aromatic ring A to form a ring, wherein the number of substitutions of the electron-donating group is 1 to 2, and the number of substitutions of the electron-withdrawing group is 1.

2. The N-aryl nuciferine derivative according to claim 1, characterized in that The electron-donating group is selected from methyl and methoxy; the electron-withdrawing group is selected from halogen or trifluoromethyl.

3. The N-aryl nuciferine derivative according to claim 2, characterized in that The electron-donating group is selected from methoxy; the electron-withdrawing group is selected from fluorine, bromine or trifluoromethyl.

4. The N-aryl nuciferine derivative according to claim 1, characterized in that The chemical structure of the N-aryl nuciferine derivative is selected from any one of the following: 。 5. The method for preparing an N-aryl nuciferine derivative according to any one of claims 1 to 4, wherein: The method includes: Pd2(dba)3 or Ph3P and BINAP are dissolved in dry toluene and continuously stirred at room temperature to ensure that the catalyst is fully dissolved and activated. Subsequently, demethylnuciferine, a bromide represented by the structural formula II and Cs2CO3 are added under an inert atmosphere, and the reaction mixture is heated to 70±5°C to react to obtain the N-arylnuciferine derivative; The molar ratio of Pd2(dba)3 or Ph3P, BINAP, Cs2CO3 and demethylnuciferine is 0.1:0.2:1~1.5:

1.

6. The preparation method according to claim 5, characterized in that The molar ratio of the bromide to demethylnuciferine is 2:1; or / and, the mass ratio of the toluene volume to demethylnuciferine is 2 mL:30 g; Or / and, after the reaction is completed, extraction is performed using ethyl acetate, the organic phase is collected, dried, concentrated, and the product is obtained by separation and purification.

7. The preparation method according to claim 5, characterized in that The preparation method of demethylnuciferine comprises: Dissolve nuciferine in dichloromethane, cool the entire reaction solution to -20 °C, and slowly add m -CPBA in dichloromethane solution, continue stirring at low temperature, then move to room temperature and continue stirring. When the raw material is converted into the intermediate product nuciferine nitrogen oxide, the reaction solution is cooled to -20 ° C again, methanol is added, and FeSO4·7H2O is added to the reaction solution. Then, the mixture is continued to stir at low temperature, then moved to room temperature and stirred to react to obtain demethylnuciferine.

8. The preparation method according to claim 7, characterized in that The nuciferine m -The molar ratio of CPBA and FeSO4·7H2O is 6.8:5.8:13.4; Or / and, the ratio of the mass of the nuciferine to the volume of dichloromethane and methanol is 1 g:10 mL:12.5 mL.

9. Use of the N-aryl nuciferine derivative according to any one of claims 1 to 4 in the preparation of anti-obesity drugs.

10. Use of the N-aryl nuciferine derivative according to any one of claims 1 to 4 in the preparation of a drug for inhibiting lipid accumulation and / or lipase activity.

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