Novel flavonoid compound as well as preparation method and application thereof

Abstract

The invention discloses a novel flavonoid compound as well as a preparation method and application thereof, and belongs to the technical field of natural medicines. The preparation method comprises the following steps: heating, refluxing and extracting with ethanol, and concentrating into thick extract under reduced pressure to obtain a crude extract; step 2, extraction; step 3, loading the dichloromethane extract on an MCI column; 4, concentrating the 30% methanol eluent to prepare a liquid phase; and step five, purifying the compound crude product (I) and the compound crude product (II) through a Sephadex LH-20 gel column respectively, and eluting with methanol to obtain the compound (I) and the compound (II) respectively. The anti-gastric cancer drug provided by the invention comprises two new flavonoid compounds in a specific mass ratio, and the composition has a more excellent anti-gastric cancer effect. According to the invention, two new flavonoid compounds are separated from the pogonatum insignis plant, and the two new compounds have good anti-gastric cancer activity, so that a foundation is laid for development and utilization of pogonatum insignis plant resources.

Description

Technical Field

[0001] The invention relates to a new flavonoid compound and a preparation method and application thereof, belonging to the technical field of natural medicines. Background Art

[0002] Polytrichum commune Hedw. belongs to the Polytrichum genus of the Polytrichum family. It usually grows in acidic and humid coniferous forests, mostly in large patches, and often mixes with plants of the genus Hedw or Hedw. It is sturdy in appearance and looks like a pine or fir seedling. The plant body is several centimeters to tens of centimeters high. The stem has a differentiated central axis, and there are a large number of reddish-brown adventitious roots at the base. The leaves are relatively stiff, with multiple layers of cells, and the ventral surface is covered with many green single-layer cell pectens; the leaf margins have coarse teeth; the midrib is wide, almost occupying the entire leaf surface. The capsule stalk is reddish-brown and several centimeters long. The spore capsule is a four-sided ellipse with a prominent platform. There are 64 capsule teeth. The capsule cap is oblate-conical, and the capsule cap is covered with many golden cilia. In acidic and humid coniferous forests, this species often grows in large patches, and often mixes with plants of the genus Hedw or Hedw.

[0003] Gastric cancer is a malignant tumor originating from the gastric mucosal epithelium. There are obvious regional differences in the incidence of gastric cancer. The incidence rate of gastric cancer in the northwest and eastern coastal areas of my country is significantly higher than that in the southern region. The age of onset is over 50 years old, and the ratio of male to female incidence is 2:1. Due to changes in dietary structure, increased work pressure and Helicobacter pylori infection, gastric cancer has shown a tendency to become younger. Gastric cancer can occur in any part of the stomach, more than half of which occur in the gastric antrum, and the greater curvature, lesser curvature and anterior and posterior walls of the stomach can be affected. The vast majority of gastric cancers are adenocarcinomas, which have no obvious symptoms in the early stage, or have non-specific symptoms such as upper abdominal discomfort and belching, which are often similar to the symptoms of chronic gastric diseases such as gastritis and gastric ulcers and are easily overlooked. Therefore, the early diagnosis rate of gastric cancer in my country is still low. The prognosis of gastric cancer is related to the pathological stage, location, tissue type, biological behavior and treatment measures of gastric cancer.

[0004] Statistics in 2018 show that the incidence of gastric cancer ranks fifth among malignant tumors worldwide, and its mortality ranks third. The 5-year survival rate of early gastric cancer after surgery can reach 90.9-100%, but there is still a lack of effective treatment for advanced gastric cancer. Even if comprehensive treatment is actively adopted, its 5-year survival rate is still less than 30%. There is no effective treatment for gastric cancer in the existing technology, and no flavonoid compounds that can treat gastric cancer have been obtained from golden moss. The extraction and separation of new flavonoid compounds from the natural drug golden moss can not only enrich flavonoid natural drugs, but also provide a certain reference for the classification of golden moss plants from the perspective of chemical taxonomy. Summary of the invention

[0005] In view of the above problems, the object of the present invention is to provide a new flavonoid compound, which is obtained by extraction, separation and purification from golden moss.

[0006] At the same time, the invention provides a preparation method of the new flavonoid compound.

[0007] At the same time, the present invention provides the use of the new flavonoid compound in the preparation of anti-gastric cancer drugs.

[0008] At the same time, the present invention provides an anti-gastric cancer drug, comprising compound (I) and compound (II), wherein the mass ratio of compound (I) to compound (II) is 1:(3-4).

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] The new flavonoid compound has the following structure:

[0011]

[0012] The preparation method of the new flavonoid compound comprises the following steps:

[0013] Step 1, taking dried plants of Polytrichum commune Hedw., crushing, sieving, and extracting at least twice with 90-95% ethanol under heating and reflux, with the amount of solvent used each time being 8-10 times the amount of the feed, each time for at least 2 hours, filtering and combining the extracts, and concentrating under reduced pressure into a thick extract to obtain a crude extract;

[0014] Step 2, after the crude extract is dispersed with hot water, it is extracted with equal volumes of petroleum ether, dichloromethane, ethyl acetate and n-butanol in sequence for 3 to 5 times, and the extracts of each polar part are then concentrated under reduced pressure to obtain extracts of different polar parts;

[0015] Step 3, the dichloromethane extract is loaded onto an MCI column, gradient eluted with a methanol-water solvent system, the 30% methanol elution portion is collected, and concentrated under reduced pressure to obtain an extract;

[0016] Step 4, dissolving the extract with an appropriate amount of methanol and filtering; using reverse phase chromatography, using 45% acetonitrile-water solution as the mobile phase, and detecting at a wavelength of 249 nm, performing preparative liquid phase separation, collecting chromatographic peaks with retention times of 16 min and 31 min, respectively, to obtain crude compound (I) and crude compound (II);

[0017] Step 5, the crude compound (I) and the crude compound (II) are purified by Sephadex LH-20 gel column, and after elution with methanol, compound (I) and compound (II) are obtained respectively.

[0018] Preferably, in step 1, the powder is sieved through a 20-30 mesh sieve after being crushed.

[0019] Preferably, in step 2, the boiling range of petroleum ether is 30-60°C.

[0020] Preferably, in step 2, the amount of hot water used is 10 to 12 times the weight of the crude extract; the amount of petroleum ether, dichloromethane, ethyl acetate and n-butanol used in each extraction is the same volume as the hot water; and the temperature of the hot water is 80 to 95°C.

[0021] Preferably, in step three, the methanol-water solvent system uses water, 30%, 50%, 70% and 90% MeOH / H2O as eluents in sequence, with each gradient elution being 3 to 5 column volumes; the diameter-to-height ratio of the MCI column is 1:(8 to 10).

[0022] Preferably, in step 4, the reverse phase C18 column is a DIKMAInspire C18 preparative column, the injection volume is 95-180 mg, the elution solvent system is acetonitrile-water, and the flow rate is 15 mL / min.

[0023] Preferably, in step five, the diameter-to-height ratio of the Sephadex LH-20 gel column is 1:(30-40).

[0024] Application of new flavonoid compounds in the preparation of anti-gastric cancer drugs.

[0025] An anti-gastric cancer drug comprises the compound (I) and the compound (II) of the present invention, wherein the mass ratio of the compound (I) to the compound (II) is 1:(3-4).

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] The present invention extracts, separates and purifies two new flavonoid compounds from the natural source of golden moss. The in vitro cytotoxic activity shows that the two new compounds have good anti-gastric cancer activity. The present invention lays a certain foundation for the in-depth development and utilization of golden moss plant resources.

[0028] The anti-gastric cancer drug of the present invention comprises two new flavonoid compounds in a specific mass ratio, and the composition has a more excellent anti-gastric cancer effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the H spectrum of compound (I) of the present invention;

[0030] Figure 2 is the C spectrum of compound (I) of the present invention;

[0031] Figure 3 is the HSQC spectrum of compound (I) of the present invention;

[0032] Figure 4is the HMBC spectrum of compound (I) of the present invention;

[0033] Figure 5 is the H spectrum of compound (II) of the present invention;

[0034] Figure 6 is the C spectrum of compound (II) of the present invention;

[0035] Figure 7 is the DEPT spectrum of compound (II) of the present invention;

[0036] Figure 8 is the HSQC spectrum of compound (II) of the present invention;

[0037] Fig. 9 is the HMBC spectrum of compound (II) of the present invention;

[0038] Fig.10 This is the HH-COSY spectrum of compound (II) of the present invention. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0040] Source of moss: The sample of Polytrichum commune Hedw. was collected in Gaopo Yunding Miao Village, Gaopo Township, Huaxi District, Guiyang City in October 2019. The specimen was identified as the whole herb of Polytrichum commune Hedw. of the Polytrichumaceae family by Professor Zhao Jiancheng of the School of Life Sciences of Hebei Normal University. The voucher specimen (HBSD2019110501) is preserved in the Laboratory of Systematics and Evolution of the School of Life Sciences of Hebei Normal University.

[0041] Example 1

[0042] Two new compounds isolated from golden moss have the following structures:

[0043]

[0044] The preparation method of the above-mentioned new flavonoid compound comprises the following steps: 1.5 kg of dried golden moss plants are crushed into coarse powder and then passed through a 30-mesh sieve, and then extracted twice with 95% ethanol under hot reflux (12 kg of solvent each time, time 2 hours), filtered and combined, and concentrated under reduced pressure at 70°C to form a thick extract (41 g) to obtain a crude extract. The crude extract is dispersed with 400 g (i.e. 400 mL) of 90°C hot water, and then extracted with petroleum ether (30-60°C), dichloromethane, ethyl acetate and n-butanol in sequence. The amount of petroleum ether, dichloromethane, ethyl acetate and n-butanol used for each extraction is 400 mL, and each extractant is extracted 4 times. The extracts of each polar part are then concentrated under reduced pressure at 60°C and dried at 50°C to obtain an extract. The dichloromethane extract (8.5 g) was dissolved in 10 mL of methanol and filtered. The filtrate was loaded onto an MCI gel column, the diameter-to-height ratio of the MCI gel column was 1:8, the amount of the MCI gel filler was 160 g, and gradient elution was performed using a methanol-water solvent system. The methanol-water solvent system used water, 30%, 50%, 70% and 90% MeOH / H2O as eluents in sequence, and each gradient elution had 3 column volumes. The 30% methanol elution portion was concentrated under reduced pressure at 60° C. and dried at 50° C. to obtain an extract (0.9 g). The extract was dissolved in 5 mL of methanol and subjected to preparative liquid separation using a reverse phase chromatography column method, 45% acetonitrile-water solution as the mobile phase, a reverse phase C18 column of DIKMAInspire C18 4.6×250 mm, an injection volume of 1 mL each time, an ultraviolet detection wavelength of 249 nm, and a flow rate of 15 mL / min. The chromatographic peak with a retention time of 16 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:30, and the amount of Sephadex LH-20 filler was 100 g. After loading, methanol was eluted for 6 column volumes, and the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (Ⅰ) (6.8 mg). The chromatographic peak with a retention time of 31 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:30, and the amount of Sephadex LH-20 filler was 100 g. After loading, eluted with methanol for 5 column volumes, and then the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (II) (8.3 mg).

[0045] The English name of compound (Ⅰ): 2',3'-Dihydrogenapigenin.

[0046] The Chinese name of compound (Ⅰ): 2′,3′-dihydroprotoapigenin.

[0047] The English name of compound (II): 2',3'-dihydroapigenin-4'-O-β-D-glucoside.

[0048] The Chinese name of compound (II): 2′,3′-dihydroprotoapigenin-4′-O-β-D-glucoside.

[0049] like Figures 1 to 10 As shown, the NMR signal assignments of the structures of compound (I) and compound (II) are shown in Table 1 and Table 2, respectively.

[0050] Table 1 Signal attribution of compound (I)

[0051]

[0052]

[0053] Table 2 Signal attribution of compound (II)

[0054]

[0055]

[0056] The present invention relates to the use of two new compounds isolated from golden moss obtained in the present invention in the preparation of anti-gastric cancer drugs.

[0057] An anti-gastric cancer drug comprises compound (I) and compound (II) of this embodiment, wherein the mass ratio of compound (I) to compound (II) is 1:3 or 1:4.

[0058] Pharmacological activity: In vitro cytotoxic activity results showed that both compounds have good anti-gastric cancer activity.

[0059] Cell viability culture:

[0060] Human gastric cancer cell lines HGC-27, SGC-7901 and BGC-823 were provided by the Cell Bank of Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences.

[0061] The cells were cultured in a DMEM high-glucose medium containing 10% fetal bovine serum, 100U / mL penicillin, and 100μg / mL streptomycin in a saturated humidity, 37°C, 5% CO2 cell culture incubator. The cell growth was observed the next day and the culture medium was replaced. When the cells covered 80% of the bottom of the culture bottle, they could be subcultured. The cell culture medium was discarded, an appropriate amount of PBS was taken to rinse the cells twice, 0.25% trypsin was added, and the cells were shaken and digested. When the cells became round, the cell culture medium was added to terminate the digestion, and the cell suspension was collected and centrifuged at 1000r / min for 3min. The supernatant was discarded and the cells were resuspended in the culture medium for subculture.

[0062] MTT assay:

[0063] Cancer cells in the logarithmic growth phase were prepared into 5×10 4 / mL cell suspension. The cells were seeded into a 96-well plate, and 100 μL of cell suspension was added to each well. Compound (I) and compound (II) were dissolved in fresh culture medium at four concentrations of 0 μM, 5 μM, 25 μM, 125 μM and 625 μM, respectively, and then added to the 96-well plate in sequence, with each concentration repeated 3 times. After culturing in the incubator for 48 hours, the culture medium of each well was aspirated and 100 μL of 0.5 mg / mL MTT solution was added. After culturing for 1 hour, the MTT solution was aspirated and 200 μL of DMSO was added to each well to dissolve the purple crystals of MTT. The UV absorbance value of each well was measured at a wavelength of 490 nm by enzyme-linked immunosorbent assay. The results of the MTT experiment are shown in Tables 3 and 4.

[0064] Table 3 MTT test results of compound (I) anti-gastric cancer activity

[0065]

[0066] Table 4 MTT test results of compound (II) anti-gastric cancer activity

[0067]

[0068] The above experimental results show that compared with the blank control group, the above two new compounds have better inhibitory effects on human gastric cancer cell lines HGC-27, SGC-7901 and BGC-823 cells.

[0069] Cancer cells in the logarithmic growth phase were prepared into 5×10 4 / mL cell suspension. The cells were seeded into a 96-well plate and 100 μL of cell suspension was added to each well.

[0070] Fresh medium 1 contained compound (I) at a concentration of 25 μM and compound (II) at a concentration of 75 μM;

[0071] Fresh medium 2 contained compound (I) at a concentration of 25 μM and compound (II) at a concentration of 100 μM;

[0072] Fresh medium 3 contained compound (I) at a concentration of 25 μM and compound (II) at a concentration of 50 μM;

[0073] Fresh medium 4 contained compound (I) at a concentration of 25 μM and compound (II) at a concentration of 125 μM;

[0074] Then, fresh medium 1 to fresh medium 4 were added to the 96-well plate in sequence, and each concentration was repeated 3 times. After 48 hours of incubation in the incubator, the medium of each well was aspirated and 100 μL of 0.5 mg / mL MTT solution was added. After 1 hour of incubation, the MTT solution was aspirated and 200 μL of DMSO was added to each well to dissolve the purple crystals of MTT. The UV absorbance value of each well was measured at a wavelength of 490 nm by enzyme-linked immunosorbent assay. The results of the MTT experiment are shown in Table 5.

[0075] Table 5 MTT test results of the anti-gastric cancer activity of the composition

[0076]

[0077] Example 2

[0078] The difference between this embodiment and embodiment 1 is only that:

[0079] The preparation method of the new flavonoid compound comprises the following steps: 1.5 kg of dried golden moss plants are crushed into coarse powder and then passed through a 20-mesh sieve, and then extracted with 90% ethanol under hot reflux for 3 times (15 kg of solvent is used each time, and the time is 2.5 hours), and the extracts are combined after filtration, and concentrated under reduced pressure at 70°C to form a thick extract (47 g) to obtain a crude extract. The crude extract is dispersed with 564 g (i.e., 564 mL) of 80°C hot water, and then extracted with petroleum ether (30-60°C), dichloromethane, ethyl acetate and n-butanol in sequence. The amount of petroleum ether, dichloromethane, ethyl acetate and n-butanol used for each extraction is 564 mL, and each extractant is extracted 3 times. The extracts of each polar part are concentrated under reduced pressure at 60°C and dried at 50°C to obtain an extract. The dichloromethane extract (8.9 g) was dissolved in 10 mL of methanol and filtered. The filtrate was loaded onto an MCI gel column, the diameter-to-height ratio of the MCI gel column was 1:10, the amount of the MCI gel filler was 180 g, and gradient elution was performed using a methanol-water solvent system. The methanol-water solvent system used water, 30%, 50%, 70% and 90% MeOH / H2O as eluents in sequence, and each gradient elution was 5 column volumes; the 30% methanol elution part was concentrated under reduced pressure at 60° C. and dried at 50° C. to obtain an extract (0.95 g). The extract was dissolved in 10 mL of methanol and prepared by a reverse phase chromatography column method, with 45% acetonitrile-water solution as the mobile phase, a reverse phase C18 column of DIKMAInspire C18 4.6×250 mm, an injection volume of 1 mL each time, an ultraviolet detection wavelength of 249 nm, and a flow rate of 15 mL / min for liquid separation. The chromatographic peak with a retention time of 16 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:40, and the amount of Sephadex LH-20 filler was 120 g. After loading, eluted with methanol for 6 column volumes, and then the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (Ⅰ) (6.9 mg). The chromatographic peak with a retention time of 31 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:40, and the amount of Sephadex LH-20 filler was 120 g. After loading, eluted with methanol for 5 column volumes, and then the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (II) (8.6 mg).

[0080] Example 3

[0081] The difference between this embodiment and embodiment 1 is only that:

[0082] The preparation method of the new flavonoid compound comprises the following steps: 1.5 kg of dried golden moss plants are crushed into coarse powder and then passed through a 30-mesh sieve, and then extracted twice with 95% ethanol under hot reflux (13.5 kg of solvent is used each time, and the time is 3 hours), and the extracts are combined after filtration, and concentrated under reduced pressure at 70°C to form a thick extract (47 g) to obtain a crude extract. The crude extract is dispersed with 517 g (i.e., 517 mL) of 95°C hot water, and then extracted with petroleum ether (30-60°C), dichloromethane, ethyl acetate and n-butanol in sequence. The amount of petroleum ether, dichloromethane, ethyl acetate and n-butanol used for each extraction is 517 mL, and each extractant is extracted 5 times. The extracts of each polar part are concentrated under reduced pressure at 60°C and dried at 50°C to obtain an extract. The dichloromethane extract (8.8 g) was dissolved in 10 mL of methanol and filtered. The filtrate was loaded onto an MCI gel column, the diameter-to-height ratio of the MCI gel column was 1:9, the amount of the MCI gel filler was 160 g, and gradient elution was performed using a methanol-water solvent system. The methanol-water solvent system used water, 30%, 50%, 70% and 90% MeOH / H2O as eluents in sequence, and each gradient elution had 4 column volumes. The 30% methanol elution portion was concentrated under reduced pressure at 60° C. and dried at 50° C. to obtain an extract (0.92 g). The extract was dissolved in 8 mL of methanol and subjected to preparative liquid separation using a reverse phase chromatography column method, 45% acetonitrile-water solution as the mobile phase, a reverse phase C18 column of DIKMAInspire C18 4.6×250 mm, an injection volume of 1 mL each time, an ultraviolet detection wavelength of 249 nm, and a flow rate of 15 mL / min. The chromatographic peak with a retention time of 16 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:35, and the amount of Sephadex LH-20 filler was 100 g. After loading, methanol was eluted for 6 column volumes, and the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (Ⅰ) (6.85 mg). The chromatographic peak with a retention time of 31 min was collected, enriched and combined, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain a crude compound. The crude product was dissolved in 2 mL of methanol, filtered, loaded, and purified on a Sephadex LH-20 column. The diameter-to-height ratio of the Sephadex LH-20 column was 1:35, and the amount of Sephadex LH-20 filler was 100 g. After loading, eluted with methanol for 5 column volumes, and then the eluate was collected, concentrated under reduced pressure at 60°C, and then dried at 50°C to obtain compound (II) (8.5 mg).

[0083] It should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in less than all of the features of the previously disclosed embodiments. Therefore, the claims that follow the detailed description are hereby expressly incorporated into the detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0084] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

[0085] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A novel flavonoid compound, characterized in that: Its structure is as follows:

2. The method for preparing the new flavonoid compound according to claim 1, characterized in that: The following steps are involved: Step 1, taking dried plants of Polytrichum commune Hedw., crushing, sieving, and extracting at least twice with 90-95% ethanol under heating and reflux, with the amount of solvent used each time being 8-10 times the amount of the feed, each time for at least 2 hours, filtering and combining the extracts, and concentrating under reduced pressure into a thick extract to obtain a crude extract; Step 2, after the crude extract is dispersed with hot water, it is extracted with equal volumes of petroleum ether, dichloromethane, ethyl acetate and n-butanol in sequence for 3 to 5 times, and the extracts of each polar part are then concentrated under reduced pressure to obtain extracts of different polar parts; Step 3, the dichloromethane extract is loaded onto an MCI column, gradient eluted with a methanol-water solvent system, the 30% methanol elution portion is collected, and concentrated under reduced pressure to obtain an extract; Step 4, dissolving the extract with an appropriate amount of methanol and filtering; using reverse phase chromatography, using 45% acetonitrile-water solution as the mobile phase, and detecting at a wavelength of 249 nm, performing preparative liquid phase separation, collecting chromatographic peaks with retention times of 16 min and 31 min, respectively, to obtain crude compound (I) and crude compound (II); Step 5, the crude compound (I) and the crude compound (II) are purified by Sephadex LH-20 gel column, and eluted with methanol to obtain compound (I) and compound (II), respectively.

3. The preparation method according to claim 2, characterized in that: In step 1, the powder is crushed and passed through a 20-30 mesh sieve.

4. The preparation method according to claim 2, characterized in that: In step 2, the boiling range of petroleum ether is 30-60°C.

5. The preparation method according to claim 2, characterized in that: In step 2, the amount of hot water used is 10 to 12 times the weight of the crude extract; the amount of petroleum ether, dichloromethane, ethyl acetate and n-butanol used in each extraction is the same volume as the hot water; the temperature of the hot water is 80 to 95°C.

6. The preparation method according to claim 2, characterized in that: In step 3, the methanol-water solvent system uses water, 30%, 50%, 70% and 90% MeOH / H2O as eluents in sequence, and each gradient elution is 3 to 5 column volumes; the diameter-to-height ratio of the MCI column is 1:(8 to 10).

7. The preparation method according to claim 2, characterized in that: In step 4, the reverse phase C18 column is a DIKMA Inspire C18 preparative column, the injection volume is 95-180 mg, the elution solvent system is acetonitrile-water, and the flow rate is 15 mL / min.

8. The preparation method according to claim 2, characterized in that: In step 5, the diameter-to-height ratio of the Sephadex LH-20 gel column is 1:(30-40).

9. Use of the new flavonoid compound according to claim 1 in the preparation of anti-gastric cancer drugs.

10. An anti-gastric cancer drug, characterized in that: It comprises the compound (I) and the compound (II) as claimed in claim 1, wherein the mass ratio of the compound (I) to the compound (II) is 1:(3-4).

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