Preparation method and application of indole diterpene compound

Abstract

The present application relates to the technical field of microbial medicine, and particularly to a preparation method and application of indole diterpenoid compounds. Specifically, the extract of plant endophytic fungus F4a after solid fermentation culture is separated and purified to obtain indole diterpenoid compounds; the plant endophytic fungus F4a is a strain with the preservation number CCTCC NO: M 2012531. The indole diterpenoid compounds provided by the present application have significant antifeedant, insecticidal and hypotensive activities, and they can be used as ideal candidate compounds of antifeedants, insecticides or hypoglycemic drugs. The compounds can be produced through fungal fermentation, and the preparation method is simple, efficient and high in product purity. The present application has good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microbial medicine, in particular to a preparation method and application of indole diterpenoid compounds. BACKGROUND

[0002] Spodoptera frugiperda (Lepidoptera: Noctuidae) is a major agricultural pest in the world, listed as one of the top ten global warning pests by the Food and Agriculture Organization of the United Nations. Its larvae can cause serious economic losses to crops such as corn, sugarcane, rice and other crops. Since its discovery in West Africa in 2016, it has spread to 130 countries around the world. Currently, chemical pesticides and genetically modified corn are widely used to protect crops from this serious pest. However, a large number of studies have shown that carbamates, organophosphates, pyrethroids and other insecticides have produced varying degrees of resistance to S. frugiperda. Therefore, the control of S. frugiperda is facing severe challenges, and in the long term, active antifeedants or insecticides of natural origin will be a safer and more sustainable control method. The present application first discovered indole diterpenoid compounds (such as compounds 7-9) with antifeeding and insecticidal activity, and the present application is also the first to discover the insecticidal activity of compounds 4-9.

[0003] Type 2 diabetes (T2DM) is a series of metabolic disorder syndromes characterized by insulin resistance and / or islet cell dysfunction, often accompanied by multiple acute and chronic complications, and has become one of the most important chronic diseases affecting the health of the Chinese people. Protein tyrosine phosphatase 1B (PTP1B) is one of the important target enzymes related to T2DM, which is a non-transmembrane protein tyrosine phosphatase. Studies have found that PTP1B affects the key to insulin secretion balance, when PTP1B activity is enhanced, the activated phosphorylated IR and IRS-1 / 2 involved in signal transduction will be dephosphorylated by PTP1B, which will terminate the signal transduction, inhibit glucose uptake by cells, and produce insulin resistance, resulting in elevated blood glucose, which is an important physiological regulator of insulin release in islets. The PTP1B inhibitory activity of indole diterpenoid compounds 1-12 in the present application is first discovered. SUMMARY

[0004] The present application aims to provide a preparation method and application of indole diterpenoid compounds.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0006] A preparation method of indole diterpenoid compounds, wherein the extract of plant endophytic fungus F4a after solid-state fermentation culture is separated and purified to obtain indole diterpenoid compounds;

[0007] The plant endophytic fungus F4a is a strain with the preservation number CCTCC NO: M 2012531.

[0008] To elaborate further,

[0009] (1) Plant endophytic fungus F4a was inoculated on PSA solid medium and cultured for 72-96 hours to activate it; the activated strain was then inoculated into rice solid medium and cultured statically for 15-35 days before use.

[0010] (2) Add an equal volume of acetone to the solid fermentation product and repeatedly extract by ultrasonication. Combine the extracts to obtain the crude extract.

[0011] (3) The crude extract was separated by silica gel column chromatography. The fractions were collected in the range of 99:1 to 60:40 by elution of dichloromethane:methanol (v / v) at a gradient of 100:0-0:100. Indole diterpenoids were obtained.

[0012]

[0013] In step 3), the separation is performed by silica gel column chromatography, with pure dichloromethane eluting to fraction F. A The dichloromethane:methanol volume ratio is 100:1-100:3, eluted to fraction F. B The volume ratio of dichloromethane to methanol is 100:4-100:6, and the elution yields fraction F. C The volume ratio of dichloromethane to methanol is 100:7-100:9, and the elution yields fraction F. D The volume ratio of dichloromethane to methanol is 100:10-100:20, and the elution yields fraction F. E The volume ratio of dichloromethane to methanol is 100:30-100:40, and the elution yields fraction F. F The dichloromethane:methanol volume ratio is 100:45-100:55, eluted to fraction F. G ;

[0014] Flow segment F B After separation using LH2O gel electrophoresis, 40-60 mL of methanol was collected as the sub-fraction F, based on the volume of methanol eluted. B3 Receive 62-100 mL of methanol as sub-fraction F B2 Receive 102-120 mL of methanol as sub-fluid F B1 Sub-flow F B3 Compound 4 was obtained by semi-preparative HPLC purification followed by elution with 75-85% methanol-water solution at a flow rate of 2.0-3.0 mL / min; subfluid fraction F B2 After purification by ODS reversed-phase column chromatography, followed by elution with methanol-water solution, the fraction eluted with 15-25% methanol-water solution is F. B2aF B2b F B2c F B2d F B2e F B2f F B2g F B2c F B2d F R 75-95min) and 9(t R 96-106min); sub-fraction F B2e F B2f F R 118-22min), 8(t R 22-30min) and 12(t R 10-18min); sub-fraction F B2g F B1 F R 30-45min), 10(t R 100-150min) and 11(t R 45-70min).

[0015] The solid culture medium in step 1) is 80-120 g of rice added to 100-150 mL of water, sterilized in a 2-3 L conical flask, and used after the medium is cooled.

[0016] Use of the prepared indole diterpenoid compounds, the compounds 1-12, in the preparation of potential hypoglycemic agents.

[0017] Use of the compounds 7-9 in the preparation of dual function agents for antifeeding and insecticidal purposes.

[0018] Use of the compounds 4-9 in the preparation of insecticides.

[0019] A novel indole diterpenoid, indole diterpenoids paspamines A-B (1-2) and paspalitrem D (3) are shown as (I),

[0020]

[0021] An application of the prepared indole diterpenoid compounds, the application of the compound 1, the compound 2, the compound 3 as preparation of hypoglycemic agents.

[0022] The present application has the advantages of:

[0023] The indole diterpenoid compounds in the present application are produced by the strain through specific fermentation conditions and processes. Since different fermentation media and culture conditions have a significant influence on the production of metabolites, the culture medium and culture condition in the present application can significantly improve the structural diversity and yield of the indole diterpenoid compounds produced by the fungus F4a, and novel indole diterpenoid compounds such as compounds 1-3 can be prepared.

[0024] The compound described in the present application can be produced by fungal fermentation, and the preparation method is simple, efficient, and the obtained product has high purity.

[0025] The indole diterpenoid compounds obtained in the present application have significant antifeedant, insecticidal and hypoglycemic activities, and they can be used as ideal candidate compounds for antifeedants, insecticides or hypoglycemic drugs. Among them, compounds 7-9 have significant antifeedant and insecticidal dual functional activity on the third instar larvae of Spodoptera exigua, compounds 4-9 have different degrees of insecticidal activity on the third instar larvae of Spodoptera exigua, and the PTP1B inhibitory activity of compounds 1-2, 4-8, 11-12 is stronger than that of the positive control NaVO4·12H2O. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The structures of compounds 1-12 provided for the embodiments of the present application.

[0027] Figure 2 The important correlations of NOESY of compounds 1-3 provided for the embodiments of the present application. 1 H- 1 H COSY and HMBC important correlations.

[0028] Figure 3 The important correlations of NOESY of compounds 1-3 provided for the embodiments of the present application.

[0029] Figure 4 The experimental ECD spectrum of compounds 1-3 provided for the embodiments of the present application in CH3OH, the calculated ECD spectrum. DETAILED DESCRIPTION

[0030] In order to better understand the content of the present application, further description is made below in combination with specific examples, but the protection scope of the present patent is not limited to this.

[0031] Preparation method of indole diterpenoid compound produced by fermentation of endophytic fungus F4a in plants

[0032] (1) The endophytic fungus F4a in plants is inoculated on PSA solid culture medium for activation for 72-96 h. The activated strain is inoculated on rice solid culture medium, and is left to culture for 30 days, and a total of 30-40 bottles are cultured.

[0033] The endophytic fungus F4a in plants is a strain with the preservation number CCTCC NO: M 2012531.

[0034] (2) An equal volume of acetone is put into each bottle of solid fermentation product, and ultrasonic extraction is performed for three times. After the acetone is dried under reduced pressure, methanol is refined to obtain a crude extract.

[0035] (3) The crude extract is separated by silica gel column chromatography, and gradient elution is performed according to the ratio of dichloromethane:methanol (v / v) of 100:0-0:100. The fraction of 99:1-60:40 is collected, and the indole diterpenoid compound is obtained.

[0036] The step 3) is separated by silica gel column chromatography, and pure dichloromethane elution is fraction F A , the volume ratio of dichloromethane:methanol is 100:1-100:2 elution is fraction F B , the volume ratio of dichloromethane:methanol is 100:4-100:6 elution is fraction F C , the volume ratio of dichloromethane:methanol is 100:7-100:9 elution is fraction F D , the volume ratio of dichloromethane:methanol is 100:10-100:20 elution is fraction F E , the volume ratio of dichloromethane:methanol is 100:30-100:40 elution is fraction F F , the volume ratio of dichloromethane:methanol is 100:50 elution is fraction F G .

[0037] Fraction F B is separated by gel LH20, and is divided into three sub-fractions according to the volume of eluted methanol. According to the elution order, 40-60 mL of methanol is received as sub-fraction F B3 , 62-100 mL of methanol is received as sub-fraction F B2 , and 102-120 mL of methanol is received as sub-fraction F B1 ; sub-fraction F B3Compound 4 was obtained by semi-preparative HPLC purification followed by elution with 75-85% methanol-water solution at a flow rate of 2.0 mL / min; subfluid fraction F B2 Seven subfluids were obtained by ODS reversed-phase column chromatography. B2a-g The fraction eluted with 15-25% methanol and water is F. B2a F was eluted with 26-35% methanol and water. B2b F was eluted with 36-45% methanol and water. B2c F was eluted with 46-55% methanol and water. B2d F was eluted with 56-65% methanol and water. B2e F was eluted with 66-75% methanol and water. B2f F was eluted with 76-85% methanol and water. B2g Sub-flow F B2c Compound 2 was obtained by elution with a 55-65% methanol-water solution at a flow rate of 2.0 mL / min. Sub-fluid fraction F... B2d The compound 3 (t) was obtained by elution with a 57-67% methanol aqueous solution at a flow rate of 2.0 mL / min. R 92.0min) and 9(t) R 98.6 min). Subflux F B2e Compound 1 was obtained by elution with 63-73% methanol-water solution at a flow rate of 2.0 mL / min. Subfluid fraction F... B2f The compound 5 (t) was obtained by elution with an 83-93% methanol aqueous solution at a flow rate of 2.0 mL / min. R 21.7min), 8(t) R 22.9min) and 12(t R 17.5 min). Subflux F B2g Compound 6 was obtained by elution with 83-93% methanol-water solution at a flow rate of 2.0 mL / min. Sub-fraction F B1 The compound 7 (t) was purified by semi-preparative HPLC, eluted with 75-85% methanol aqueous solution at a flow rate of 2.0 mL / min. R 42.7min), 10(t) R 134.7 min) and 11 (t R 47.1 min).

[0038] In step 1), the solid culture medium is made by adding 100g of rice to every 120mL of water, sterilizing it in a 3L Erlenmeyer flask, and using it after the culture medium has cooled down.

[0039] The above provides the structural analysis of the indole diterpenoid compounds paspamines AB (1-2) and paspalitrem D (3) (see above).Figures 1-4

[0040] Compound 1 was a brown powder. HRESIMS data showed m / z 470.2913 [M-H] - (calcd C 28 H 40 NO5, 470.2907), suggesting a molecular formula of C 28 H 41 NO5with 9 degrees of unsaturation. One ketone carbonyl, one ester carbonyl, six aromatic carbons (two of which are non- protonated), four sp 3 hybridized methines (two of which are oxygenated methines), seven methylenes, five methyl groups, and four quaternary carbons were shown in the 1D NMR spectrum (Table 1) and HSQC spectrum. By careful comparison, the 1D NMR spectrum of compound 1 was similar to that of the known indole diterpene paspaline (10). The main difference between compound 1 and 10 is that C-2 (δ C 151.2) and C-18 (δ C 115.8) of compound 10 are replaced by two carbonyl carbons (δ C 176.5 and 201.3) of compound 1. Based on the 9 degrees of unsaturation of compound 1, removing the presence of six aromatic carbons and two carbonyls, it was deduced that compound 1 is a tetracyclic system. In addition, the δ H 12.23 resonance signal indicates the presence of a carboxyl group. It was thus deduced that the C-2-C-18 double bond of the indole ring was first oxidized to form an eight-membered ketoamide ring, and then the amide bond was broken to generate compound 1. The observation of H3-25 / C-2, H2-17 / C-18, and H-20 / C-18 correlations in the HMBC correlation spectrum ( Figure 2 ) confirmed that compound 1 is the cleavage product of the indole ring of compound 10. Based on the above data and deduction, the planar structure of compound 1 was determined ( Figure 1 ).

[0041] The relative configuration of compound 1 was determined by the NOESY spectrum ( Figure 3 ). The long-range correlations of H-16 / H3-26 / H-30, H3-25 / H-13 / H-7 / H-9, and the lack of long-range correlation of H-16 and H3-25 were observed in the NOESY spectrum, suggesting that compound 1 has the same relative configuration (3S*,4S*,7S*,9S*,12S*,13R*,16S*) as compound 10. By fitting the experimental ECD and calculating the ECD spectrum, the absolute configuration of compound 1 was determined to be 1a-(3S,4S,7S,9S,12S,13R,16S) ( Figure 4 ​). Compound 1 is a new compound, named as paspamine A.

[0042] Compound 2 is a brown powder, HRESIMS data shows m / z 468.2391 [M-H] - (calcd C 27 H 34 NO6, 468.2386), its molecular formula is speculated as C 27 H 35 NO6, with 11 degrees of unsaturation. The 1D NMR spectrum (Table 1) and HSQC spectrum data of compound 2 are similar to those of compound 1. The main difference between the two is the presence of an α,β-unsaturated pyrone fragment in C-10~C-12 of compound 2, which can be inferred from the HMBC spectrum (Fig. 2) that H-9 is related to C-10 and C-7, respectively, and H-11 is related to C-7 and C-13, respectively Figure 2 ). At the same time, compound 2 has 2 more degrees of unsaturation than compound 1, which also proves the existence of an α,β-unsaturated pyrone fragment. Based on the above data and analysis, the planar structure of compound 2 is determined Figure 1 ).

[0043] The relative configuration of compound 2 is determined by the NOESY spectrum Figure 3 ). In the NOESY spectrum, long-range correlations between H-16 / H3-26, H3-25 / H-13 / H-7 / H-9 can be observed, while long-range correlations between H-16 and H3-25 are absent, suggesting that compound 2 has the same relative configuration as compound 1 (3S*,4S*,7S*,9R*,13R*,16S*). Through fitting experimental ECD and calculating ECD spectrum, the absolute configuration of compound 2 is determined to be 2a-(3S,4S,7S,9R,13R,16S) Figure 4 ). Compound 2 is a new compound, named as paspamine B.

[0044] Compound 3 is a brown powder, HRESIMS data shows m / z 532.2703 [M-H] - (calcd C 32 H 38 NO6, 532.2699), its molecular formula is speculated as C 32 H 39 NO6, with 14 degrees of unsaturation. In the 1D NMR spectrum (Table 1) and HSQC spectrum, two ketone carbonyl groups, one ester carbonyl group, six aromatic carbons (two of which are non-protic), four olefinic carbons (two of which are non-protic), two sp 3Hybrid methine (one oxomethine), six methylenes, six methyls, five quaternary carbons. By careful comparison, the 1D NMR spectrum of compound 3 was similar to that of the known indole diterpene paspalitrem C (6). The major difference between compound 3 and 6 was the presence of two carbonyl carbons (δ C 173.9 and 208.4) in compound 3, suggesting the presence of two additional oxygen atoms in compound 3. From the HMBC correlation spectrum ( Figure 2 ), it was observed that 1-NH and H3-25 were correlated to C-2, and H2-17 was correlated to C-18, respectively, indicating that the double bond between C-2 and C-18 in compound 6 was replaced by two carbonyl groups in compound 3. This suggested the presence of an eight-membered ketoamide ring in compound 3, formed by the cleavage of the double bond between C-2 and C-18 of the indole ring. Based on the above data and deduction, the planar structure of compound 3 was determined ( Figure 1 ).

[0045] The relative configuration of compound 3 was determined from the NOESY spectrum ( Figure 3 ). In the NOESY spectrum, long-range correlation was observed between H-16 and H3-26, and between 13-OH and H3-25, but not between H-16 and H3-25, suggesting that H-16 and H3-25 were not in the same plane. The C-7-C-12 NMR data of compound 3 were similar to those of compound 6, indicating that C-7 and C-9 of the two compounds had the same relative configuration. Therefore, the relative configuration of compound 3 was confirmed to be (3S*,4R*,7S*,9R*,13S*,16S*). By fitting the experimental ECD and calculating the ECD spectrum, the absolute configuration of compound 3 was determined to be 3a-(3S,4R,7S,9R,13S,16S) ( Figure 4 ). Compound 3 is a novel compound that has not been reported in the literature, and is named as paspalitrem D.

[0046] The remaining nine known indole diterpene compounds were identified as paspalinine (4), paspalicine (5), paspalitrem C (6), dehydroxypaxilline (7), 7-methoxy-13-dehydroxypaxilline (8), 6,7-dehydropaxilline (9), paspaline (10), paspaline B (11), and penijanthine D (12) by comparison with the literature-reported NMR data.

[0047] Table 1.1H and13C NMR data of compounds 1-3 1 H and 13CNMR data (DMSO-d6, 600 / 150 MHz, δ in ppm)

[0048]

[0049] Antifeedant and insecticidal activity of indole diterpenoids

[0050] Antifeedant activity determination method: third instar larvae of Helicoverpa armigera were selected, and the sample was evaluated for antifeedant function by the double-leaf disc selection method. Fresh corn leaves with uniform thickness and cleanliness were punched into 1 cm diameter round leaf discs using a puncher. The treatment group was treated with the test solution (the above compound), and each test product was prepared into two different concentrations of 80 μM and 40 μM using methanol, and 20 μL of each was evenly coated on the surface of the leaf disc. The blank control group was coated with the same volume of methanol solution. After the leaf discs were naturally dried, they were placed in a pre-wetted filter paper culture dish (9 cm in diameter), and 2 pieces of treated leaf discs and 2 pieces of control leaf discs were placed in each culture dish, and they were placed in a cross pattern. 2 starved third instar larvae of Helicoverpa armigera were placed in each culture dish, and the culture dish was placed in a light incubator with a temperature of 25±2℃ and a humidity of 70%. After 24 hours, the area of each leaf disc that was eaten was measured using coordinate grid paper. The experiment was repeated at least 5 times. The antifeedant rate was calculated as follows: antifeedant rate (%) = (AC-AT) / (AC+AT) x 100%, where AC and AT represent the area of the leaf disc that was eaten in the blank control group and the sample treatment group, respectively.

[0051] Insecticidal activity determination method: third instar larvae of Helicoverpa armigera were selected, and the sample was evaluated for insecticidal activity by the artificial feed method. The test solution (the above compound) was added to the artificial feed, and each test product was prepared into two different concentrations of 80 μM and 40 μM using methanol, and was used after the methanol was volatilized. The test group was fed with artificial feed containing the test solution. The control group was fed with artificial feed treated with an equal amount of methanol. Each treatment group had 30 larvae. The corrected mortality rate was measured after 72 hours.

[0052] Experimental results: As shown in Table 2, compounds 7-9 had strong antifeedant activity against third instar larvae of Helicoverpa armigera at a concentration of 80 μM after 24 hours (AI values were 93.8%, 99.6%, and 99.2%, respectively). Compounds 4-9 had strong insecticidal activity against third instar larvae of Helicoverpa armigera at a concentration of 80 μM after 72 hours (corrected mortality rates were 60.7%-93.0%). It is worth noting that the indole diterpenoids (such as compounds 7-9) of the present application were first discovered to have both antifeedant and insecticidal activity, and the insecticidal activity of compounds 4-9 in the present application was also first discovered.

[0053] Table 2 Antifeedant and insecticidal activity of compounds 1-12

[0054]

[0055] "-" means no antifeeding and insecticidal activity.

[0056] Hypoglycemic activity of indole diterpenoids of Example 3

[0057] Method: The screening model used E. coli system to express human protein tyrosine phosphatase 1B (PTP1B). PTP1B recombinant protein can hydrolyze the phospholipid bond of substrate p-nitrophenyl phosphate disodium (pNPP), and the product p-nitrophenol (pNP) has strong light absorption at 405 nm. Test samples (compounds 1-12) were prepared into 800 μM / L stock solution with 10% DMSO, and diluted into series concentrations of 400 μM / L and 200 μM / L. 10 μL of test sample solution and 81 μL of enzyme solution were mixed thoroughly and placed in a 37°C incubator for 10 min. Then 4 μL of substrate solution was added, and after 30 min in a 37°C incubator, 5 μL of NaOH termination solution was added, and the absorbance value was measured at an absorption wavelength of 405 nm. NaVO4-12H2O was used as a positive control.

[0058] Experimental results: As shown in Table 3, compounds 1-12 all showed PTP1B inhibitory activity to varying degrees, with EC 50 between 5.40-19.24 μM. Compounds 1-2, 4-8, 11 and 12 had PTP1B inhibitory activity (EC 50 = 5.40-8.21 μM) stronger than the positive control NaVO4-12H2O (EC 50 = 9.79 μM). It is worth noting that the PTP1B inhibitory activity of indole diterpenoids 1-12 is reported for the first time.

[0059] Table 3 PTP1B inhibitory activity of compounds 1-12

[0060]

Claims

1. Use of an indole diterpene compound, characterized in that: Use of indole diterpene compound in preparation of antifeedant and insecticidal bifunctional preparation and hypoglycemic agent The structural formula of the indole diterpene compound is .

2. The use of the indole diterpene compound according to claim 1, characterized by: The preparation method of the indole diterpene compound is as follows: the extract of the plant endophytic fungus F4a after solid fermentation culture is separated and purified to obtain the indole diterpene compound. The plant endophytic fungus F4a is a strain with the preservation number CCTCCM 2012531.

3. The indole diterpene compound for use according to claim 2, characterized in that: (1) the plant endophytic fungus F4a is inoculated on a PSA solid culture medium for activation for 72-96 hours; the activated strain is inoculated on a rice solid culture medium, and is left to culture for 15-35 days; (2) the solid fermentation product is repeatedly ultrasonically extracted with equal volume of acetone, and the combined extract is the obtained crude extract; (3) the crude extract is separated by silica gel column chromatography, eluted with dichloromethane:methanol in a gradient of 100:0-0:100, and the components of 99:1-60:40 are collected to obtain the indole diterpene compound.

4. The use of the indole diterpene compound according to claim 3, characterized by: The step 3) is isolated by silica gel column chromatography, and the pure dichloromethane elution is fraction F A , the volume ratio of dichloromethane:methanol is 100:1-100:3 elution is fraction F B , the volume ratio of dichloromethane:methanol is 100:4-100:6 elution is fraction F C , the volume ratio of dichloromethane:methanol is 100:7-100:9 elution is fraction F D , the volume ratio of dichloromethane:methanol is 100:10-100:20 elution is fraction F E , the volume ratio of dichloromethane:methanol is 100:30-100:40 elution is fraction F F , the volume ratio of dichloromethane:methanol is 100:45-100:55 elution is fraction F G ; Flow fraction F B Separation by gel LH20, receiving 40-60 mL methanol as sub-flow fraction F B3 , receiving 62-100 mL methanol as sub-flow fraction F B2 , receiving 102-120 mL methanol as sub-flow fraction F B1 ; purifying sub-flow fraction F B3 by semi-preparative HPLC, eluting with 75-85% methanol water solution at a flow rate of 2.0-3.0 mL / min; purifying sub-flow fraction F B2 by ODS reverse phase column chromatography, eluting with methanol water solution, 15-25% methanol water eluting F B2a , 26-35% methanol water eluting F B2b ; 36-45% methanol water eluting F B2c ; 46-55% methanol water eluting F B2d ; 56-65% methanol water eluting F B2e ; 66-75% methanol water eluting F B2f ; 76-85% methanol water eluting F B2g ; purifying sub-flow fraction F B2d by eluting with 57-67% methanol water solution at a flow rate of 2.0-3.0 mL / min to obtain the indole diterpene compound.

5. The use of the indole diterpene compound according to claim 3, characterized by: In step (1), the solid culture medium is prepared by adding 80-120 g of rice to 100-150 mL of water, sterilizing in a 2-3 L conical flask, and using after the culture medium is cooled.

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