Separation, synthesis and application of active sponge cyclic peptide compound

Abstract

The invention discloses a sponge cyclic peptide compound and cyclic dipeptide, which comprise two amino acid fragments, namely proline and methionine sulfoxide, and provides application of the sponge cyclic peptide compound in an anti-Parkinson medicine, and the sponge cyclic peptide compound can obviously improve the movement speed of lesion zebrafish. Compared with the prior art, the invention has the advantages that a new compound is provided for developing and researching an anti-Parkinson medicine, and separation, synthesis and application of the active sponge cyclic peptide compound are provided.

Description

Technical Field

[0001] This invention relates to the field of medicinal chemistry, specifically to the isolation, synthesis, and application of an active sponge cyclic peptide compound. Background Technology

[0002] Sponges are a type of primitive multicellular animal that are widely distributed. However, they often contain many structurally rare secondary metabolites with anticancer activity, making them a preferred research subject for marine natural product chemists.

[0003] Cyclic dipeptides in sponges have attracted widespread interest due to their unique molecular structure and diverse biological activities. These natural products are usually derived from marine organisms and have important biological activities such as antimicrobial, antitumor, and anti-inflammatory effects.

[0004] Due to its potential pharmacological and medical applications, in-depth research on sponge cyclic dipeptides has become a hot topic in modern organic synthesis and drug development.

[0005] Therefore, the applicant proposes a new study based on active sponge cyclic peptide compounds. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide the isolation, synthesis and application of an active sponge cyclic peptide compound based on sponges of the genus *Dendrocera* from the waters surrounding Xuwen County, Zhanjiang City, Guangdong Province, China.

[0007] To solve the above-mentioned technical problems, the technical solution provided by the present invention is: an active sponge cyclic peptide compound, which is a cyclic dipeptide comprising two amino acid fragments, namely proline and methionine sulfoxide.

[0008] Preferably, its chemical structural formula is one of the following compounds:

[0009] .

[0010] Another aspect of this invention discloses a method for extracting sponge cyclic peptide alkaloids, comprising the following steps:

[0011] Step 1: Extraction: After the sponge sample is dried and pulverized, it is extracted by percolation with an organic solvent. The extracts are combined and concentrated under reduced pressure to obtain the total extract.

[0012] Step 2: Extraction: The total extract is suspended in water and extracted 3-5 times with equal volumes of petroleum ether, ethyl acetate and n-butanol respectively. The extracts are combined and concentrated under reduced pressure to obtain the n-butanol extract phase.

[0013] Step 3: Separation: The n-butanol extract from Step 2 was subjected to silica gel column chromatography with gradient elution using CH2Cl2-CH3OH eluent to obtain 6 fractions (Frs.1~6). Frs.5 was further separated using mass spectrometry with Sephadex LH-20 to obtain 5 fractions (Frs.5-1~5-5).

[0014] Step 4: Mass spectrometry-guided separation: Based on the fragment ion information and chromatographic retention behavior obtained, Frs.5-3 was further separated and purified by HPLC to obtain the target compound.

[0015] Preferably, the sponge sample in step 1 is a sponge called Dysideasp., and the organic solvent is any one of ethanol, methanol, and propanol.

[0016] Preferably, the silica gel column chromatography method in step 3 is: dichloromethane:methanol = 100:0, 100:1, 100:3, 100:5, 100:7, 100:10, 100:15, 100:20, 100:30, 100:50, 50:50, 0:100;

[0018] The elution conditions for Sephadex LH-20 are: dichloromethane:methanol = 1:1, and a dropping rate of 5 seconds / drop.

[0019] The HPLC separation conditions in step 4 are as follows: the molecular ion peak at 267.07 is detected in positive ion mode;

[0020] Compounds (+)-1, (+)-2, and 3 were obtained by using a YMC-PackODS-A column with CH3OH / H2O = 10:90, a flow rate of 8 mL / min, and a detection wavelength of 210 nm.

[0021] Chiral column was used for further separation of 3. The mobile phase ratio of the chiral column was CH3OH / H2O=100:0, the flow rate was 0.6 mL / min, and the detection wavelength was 210 nm, to obtain optically pure enantiomers (+)-3 and (-)-3.

[0022] Another aspect of this invention discloses a method for synthesizing a sponge cyclic peptide alkaloid, comprising the following steps:

[0023] Step 1: Separate the two pairs of diastereomers to obtain the monomeric compounds:

[0024] (S)-Fmoc-L-MetO, (R)-Fmoc-L-MetO, (S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO;

[0025] Step 2: Condense the monomeric compounds obtained in Step 1 with L-proline methyl ester and D-proline methyl ester, respectively;

[0026] Step 3: Fmoc deprotection: Fmoc deprotection was performed using a 20% piperidine DMF solution;

[0027] Step 4: Cyclolysis: Head-to-tail cyclization was performed using the polar organic solvent MeOH. The reaction was carried out at room temperature for 24 hours. After the reaction was completed by TLC, the compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 were obtained by purification.

[0028] Preferably, the diastereomers in step 1 are:

[0029] Fmoc-L-MetO: [(S)-Fmoc-L-MetO and (R)-Fmoc-L-MetO];

[0030] Fmoc-D-MetO: [(S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO];

[0031] Separation was performed using a Chiralpak IC-3 column (5 μm, 10 × 250 mm), a mobile phase ratio of MeOH / CO2 / 0.1% TFA = 55 / 45, and a flow rate of 5.0 mL / min.

[0032] Preferably, step 2 includes:

[0033] Weigh (R)-Fmoc-L-MetO, (S)-Fmoc-D-MetO, (R)-Fmoc-L-MetO, (S)-Fmoc-D-MetO, (R)-Fmoc-D-MetO, (S)-Fmoc-L-MetO, (R)-Fmoc-D-MetO, (S)-Fmoc-L-MetO, (R)-Fmoc-D-MetO, (S)-Fmoc-L-MetO into eight round-bottom flasks, and measure dichloromethane to completely dissolve them.

[0034] Add Et3N and DCC to the above round-bottom flasks at 0℃, stir for 5 min, then add L-proline methyl ester salt to round-bottom flasks No. 1, No. 4, No. 6 and No. 7, and D-proline methyl ester salt to round-bottom flasks No. 2, No. 3, No. 5 and No. 8.

[0035] The reaction was carried out overnight at room temperature and detected by TLC. After the reaction was completed, the mixture was washed with saturated brine, extracted three times with dichloromethane, and the organic layer was dried with anhydrous Na2SO4 and then evaporated to dryness to obtain the crude product.

[0036] The crude product was purified by silica gel column chromatography (petroleum ether / ethyl acetate = 95:5) to obtain intermediate product A1-H1;

[0037] In step 3, A1-H1 is weighed into a round-bottom flask and 20% piperidine DMF solution is added at room temperature (V 哌啶 V DMF =1 : 4), slowly raise the temperature to 80 ℃, react for 30 min, and after TLC detection of complete reaction, evaporate the reaction solution to dryness to obtain a pale yellow solid.

[0038] Preferably, the polar solvent in step 4 is methanol;

[0039] After the reaction was confirmed to be complete by TLC, the reaction solution was evaporated to dryness under vacuum and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 90:10) to obtain the target compound.

[0040] This invention also discloses the application of sponge cyclic peptide alkaloids in anti-Parkinson's drugs, wherein the sponge cyclic peptide compounds are used to improve the movement speed of diseased zebrafish.

[0041] The advantages of this invention compared with the prior art are as follows: This invention is based on the study of sponge Dysideasp., and obtains active sponge cyclic peptide compounds through the extraction and synthesis of sponge cyclic peptide alkaloids. The preparation method is simple and easy to promote and use, providing new compounds for the development and research of anti-Parkinson's drugs and providing a scientific basis for the development and utilization of marine medicinal resources. Attached Figure Description

[0042] Figure 1 This is the HMBC diagram of the spongy cyclic peptide compound (+)-2.

[0043] Figure 2 This is the NOESY diagram of the sponge cyclic peptide compound (+)-2.

[0044] Figure 3 This is the ECD image of the spongy cyclic peptide compound (+)-2.

[0045] Figure 4 This is the UV spectrum of sponge cyclic peptide compound 3.

[0046] Figure 5 This is the IR spectrum of sponge cyclic peptide compound 3.

[0047] Figure 6 This is the HR-ESI-MS image of sponge cyclic peptide compound 3.

[0048] Figure 7 It is a sponge cyclic peptide compound 3. 1 H NMR spectrum.

[0049] Figure 8 It is a sponge cyclic peptide compound 3. 13 C NMR spectrum.

[0050] Figure 9 This is a DEPT 135 plot of sponge cyclic peptide compound 3.

[0051] Figure 10 This is an X-ray schematic diagram of (S)-Fmoc-D-MetO.

[0052] Figure 11 This is an X-ray schematic diagram of (R)-Fmoc-D-MetO.

[0053] Figure 12 This is an X-ray schematic diagram of the synthesized sponge cyclic peptide compound (+)-1.

[0054] Figure 13 It is a synthetic sponge cyclic peptide compound (-)-1 13 C NMR spectrum.

[0055] Figure 14 This is an X-ray schematic diagram of the synthesized sponge cyclic peptide compound (-)-1.

[0056] Figure 15 This is an HR-ESI-MS image of the synthesized sponge cyclic peptide compound (+)-2.

[0057] Figure 16 It is a synthetic sponge cyclic peptide compound (+)-2. 1 H NMR spectrum.

[0058] Figure 17 It is a synthetic sponge cyclic peptide compound (+)-2. 13 C NMR spectrum.

[0059] Figure 18 This is an HR-ESI-MS image of the synthesized sponge cyclic peptide compound (-)-2.

[0060] Figure 19 It is the total synthetic route for compounds (+)-1, (+)-2, (+)-3 and (-)-3, as well as four other possible optical isomers.

[0061] Figure 20 This is a comparison of the swimming speed and distance of zebrafish in a 48-well plate. Detailed Implementation

[0062] The present invention will now be described in further detail with reference to the accompanying drawings.

[0063] A method for extracting sponge cyclic peptide alkaloids includes the following steps:

[0064] Step 1, Extraction: The sponge Dysidea sp. sample was dried and pulverized, extracted by percolation with an organic solvent, and the extracts were combined and concentrated under reduced pressure to obtain the final extract.

[0065] The organic reagent in the first step is 95% ethanol;

[0066] The sponge was collected from the sea area surrounding Xuwen County, Zhanjiang City, Guangdong Province, China, belonging to the genus *Spongeia*.

[0067] The second step is extraction: The extract is suspended in water and extracted 3 to 5 times with equal volumes of organic reagents petroleum ether, ethyl acetate and n-butanol. The extracts are combined and concentrated under reduced pressure to obtain the n-butanol extract.

[0068] The third step was separation: the n-butanol extract was subjected to silica gel column chromatography with gradient elution using CH2Cl2-CH3OH eluent, yielding six fractions (Frs. 1-6). Frs. 5 was further separated using mass spectrometry with a Sephadex LH-20 spectrometer (CH2Cl2:MeOH = 1:1), yielding five fractions (Frs. 5-1-5-5).

[0069] Step 4, liquid phase separation: Frs. 5-3 was further purified by HPLC (YMC-Pack ODS-A, CH3OH / H2O = 10 / 90, flow rate = 8 mL / min), finally yielding compound (+)-1 (0.6 mg, t R = 22 min),(+)-2 (0.7 mg, t R = 25 min), 3 (0.7 mg, t R = 28 min). Further separation of 3 was performed using a chiral column (Lux® 5μm Amylose-1, 5 μm, 4.6 × 250 mm, CH3OH / H2O = 100 / 0, flow rate = 0.6 mL / min), yielding optically pure enantiomer (+)-3 (0.3 mg, t). R = 28 min), (-)-3 (0.3 mg, t R = 28min)

[0070] A method for synthesizing sponge cyclic peptide alkaloids includes the following steps:

[0071] The first step was the separation of diastereomers: Two pairs of diastereomers were commercially available precursors: Fmoc-L-MetO [(S)-Fmoc-L-MetO and (R)-Fmoc-L-MetO] and Fmoc-D-MetO [(S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO]. We used supercritical CO2 chromatography to perform chiral separation of the two pairs of diastereomers, Fmoc-L-MetO and Fmoc-D-MetO. Through column selection and mobile phase optimization, baseline separation was successfully achieved using a semi-preparative Chiralpak IC-3 column on a Waters SFC Prep 15 system. After comparison with literature data and X-ray single-crystal diffraction experiments, the four optically pure monomeric compounds were finally identified as: (S)-Fmoc-L-MetO (2.3 g, t...). R = 7.807 min), (R)-Fmoc-L-MetO (2.5 g, t R = 9.007min), (S)-Fmoc-D-MetO (2.5 g, t R = 10.807 min) and (R)-Fmoc-D-MetO (2.0 g, t R =12.179 min).

[0072] The second step is condensation: the optically pure synthetic precursors obtained after separation are condensed with L-proline methyl ester and D-proline methyl ester respectively. The condensation reagent is dicyclohexylcarbodiimide (DCC), and the reaction process is monitored by TLC.

[0073] Step 3, Fmoc deprotection: using a 20% piperidine DMF solution (V 哌啶 V DMF = 1 : 4) Perform Fmoc deprotection;

[0074] Step 4, cyclization: Head-to-tail cyclization was performed using the polar organic solvent MeOH at room temperature for 24 hours. After TLC detection to confirm complete reaction, the mixture was purified to obtain compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, (-)-4

[0075] The steps of the first step are as follows: Using a Chiralpak IC-3 column (5 μm, 10 × 250 mm), the mobile phase ratio was MeOH / CO2 / 0.1% TFA = 55 / 45, and the flow rate was 5.0 mL / min. The above two pairs of epimers were successfully separated.

[0076] The second step is as follows: Weigh (R)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol), and (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol) into eight 50 mL round-bottom flasks, and measure 10... Dissolve the substance completely in dichloromethane. Add Et3N (0.30 g, 3 mmol) and DCC (0.74 g, 3.6 mmol) to the round-bottom flask at 0 °C. After stirring for 5 min, add L-proline methyl ester salt (1.16 g, 3.0 mmol) to round-bottom flasks 1, 4, 6, and 7, and D-proline methyl ester salt (1.16 g, 3.0 mmol) to round-bottom flasks 2, 3, 5, and 8. React overnight at room temperature and monitor by TLC. After the reaction, wash with saturated brine, extract three times with dichloromethane, and dry the organic layer with anhydrous Na2SO4. The crude product was purified by silica gel column chromatography (petroleum ether / ethyl acetate = 95:5) to obtain intermediate A1-H1 (1.3 g, yield 90.0%).

[0077] The third step is as follows: Weigh A1-H1 (0.50 g, 1.0 mmol) into a 50 mL round-bottom flask, and add 20% piperidine DMF solution (V) at room temperature. 哌啶 V DMF = 1 : 4). The temperature was then slowly increased to 80 ℃, and after reacting for 30 min, the reaction was confirmed to be complete by TLC. The reaction solution was then evaporated to dryness to obtain a pale yellow solid.

[0078] The fourth step is as follows: Add 20 mL of the polar solvent methanol to the system, react at room temperature for 24 hours, and after the reaction is complete as detected by TLC, evaporate the reaction solution to dryness under vacuum. Purify by silica gel column chromatography (petroleum ether / ethyl acetate = 90:10) to obtain the target products: (+)-1 (0.08 g, 34.7%), (-)-1 (0.07 g, 30.4%), (+)-2 (0.08 g, 34.7%), (-)-2 (0.08 g, 34.7%), (+)-3 (0.07 g, 30.4%), (-)-3 (0.07 g, 30.4%), (+)-4 (0.07 g, 30.4%), and (-)-4 (0.09 g, 39.1%).

[0079] Unless otherwise specified, all reagents used in the examples are commercially available. Example 1

[0080] Sponge alkaloids (+)-1, (+)-2, (+)-3 and (-)-3 were discovered and extracted from sponges;

[0081] The crude fraction of *Dysidea* sp. collected from the waters near Xuwen County, Zhanjiang City, Guangdong Province, China, was separated using preparative liquid chromatography to yield a new class of cyclic peptides, namely sponge cyclic peptides (+)-1, (+)-2, (+)-3, and (-)-3. The application of precursor ion scanning mass spectrometry in the compound screening of this invention is specifically as follows:

[0082] (1) Optimization of sample pretreatment conditions:

[0083] Elution was performed using silica gel column chromatography with gradients of dichloromethane:methanol: 100:0, 100:1, 100:3, 100:5, 100:7, 100:10, 100:15, 100:20; 100:30, 100:50, 50:50, and 0:100. Sephadex LH-20 gel column chromatography was then performed with dichloromethane:methanol = 1:1 at a dropping rate of 5 seconds / drop. High-performance liquid chromatography (HPLC) was then used to effectively remove impurities and enrich the cyclic peptide component.

[0084] (2) Optimization of liquid phase conditions:

[0085] To achieve baseline separation of the target components and facilitate their targeted acquisition, optimal isocratic separation conditions were determined, resulting in compounds (+)-1, (+)-2, (+)-3, and (-)-3.

[0086] The specific steps for extracting sponge cyclic peptide compounds (+)-1, (+)-2, (+)-3 and (-)-3 from sponges are as follows:

[0087] Step 1, Extraction: Dysidea sp. (10 kg) was collected from the sea area around Xuwen County, Zhanjiang City, Guangdong Province, China. After drying and crushing, it was extracted five times with 5.0 L of 95% ethanol by percolation. The extracts were combined and concentrated under reduced pressure. The ethanol was recovered and concentrated to obtain a total extract (1.8 kg).

[0088] Step 2, Extraction: The total extract was suspended in water and extracted three times with an equal volume of petroleum ether. The extracts were combined and concentrated under reduced pressure to obtain the petroleum ether fraction (300 g). The remaining extract was suspended in water and extracted three times with an equal volume of ethyl acetate. The extracts were combined and concentrated under reduced pressure to obtain the ethyl acetate fraction (40 g). The remaining extract was further extracted with n-butanol to obtain the n-butanol fraction (180 g).

[0089] Step 3, separation: 180 g of the n-butanol extract was subjected to silica gel column chromatography using a gradient elution of dichloromethane:methanol = 100:0, 100:1, 100:3, 100:5, 100:7, 100:10, 100:15, 100:20; 100:30, 100:50, 50:50, 0:100, yielding 6 fractions (Frs. 1~6). Frs. 5 was further separated using mass spectrometry with a Sephadex LH-20 spectrometer (CH2Cl2:CH3OH = 1:1), yielding 5 fractions (Frs. 5-1~5-5).

[0090] Step 4, liquid phase separation: Frs. 5-3 was further purified by HPLC (YMC-Pack ODS-A, CH3OH / H2O = 10 / 90, flow rate = 8 mL / min), finally yielding compound (+)-1 (0.6 mg, t R = 22 min),(+)-2 (0.7 mg, t R = 25 min), 3 (0.7 mg, t R = 28 min). Further separation of 3 was performed using a chiral column (Lux® 5μm Amylose-1, 5 μm, 4.6 × 250 mm, CH3OH / H2O = 100 / 0, flow rate = 0.6 mL / min), yielding optically pure enantiomer (+)-3 (0.3 mg, t). R = 28 min), (-)-3 (0.3 mg, t R= 28min);

[0091] The structures of compounds (+)-1, (+)-2, (+)-3 and (-)-3 are shown below:

[0092]

[0093] The physicochemical properties and NMR data of the sponge cyclic peptide compounds (+)-1, (+)-2, (+)-3 and (-)-3 obtained through the above steps are as follows:

[0094] Compound (+)-1: white amorphous powder, mp. 142-143 ℃; [α]25 D +4.4 (c 0.25, CH3OH); HR-ESI-MS m / z 245.0954 [M + H] + (calcd for C 10 H 17 N2O3S: 245.0954); UV(CH3OH) λ max : 224 nm; IR (KBr) ν max : 3329, 2944, 2833, 1652, 1452, 1019, 616 cm -1 ;CD (CH3OH)λ max nm (Δε): 212 (2.06), 227 (-0.63);

[0095] Compound (+)-2: white amorphous powder, mp. 147-148 ℃; [α]25 D +6.1 (c 0.25, CH3OH); HR-ESI-MS m / z 267.0762 [M + Na] + (calcd for C 10 H 16 N2O3SNa: 267.0774); UV(CH3OH) λ max : 224 nm; IR (KBr) ν max : 3352, 2927, 1646, 1430, 1299, 1182, 1126,1014, 947 cm -1 ;CD (CH3OH)λ max nm (Δε): 220 (-1.93), 244 (0.26);

[0096] Compounds (+)-3 and (-)-3: white amorphous powder, mp. 140–141 °C; HR-ESI-MS m / z 267.0766 [M + Na] + (calcd for C 10 H 16 N2O3SNa: 267.0774); UV (CH3OH) λ max : 218 nm; IR(KBr) ν max : 3380, 1645, 1449, 1297, 1159, 1119, 1007, 945 cm -1 ;

[0097] (+)-3: [α] +6.2 (c 0.25, CH3OH); CD (CH3OH) λ max nm (Δε): 219 (2.34).

[0098] (-)-3: [α] -6.4 (c 0.25, CH3OH); CD (CH3OH) λ max nm (Δε): 218 (-2.6).

[0099] The NMR spectral data of sponge cyclic peptide compounds (+)-1, (+)-2 and 3 are shown in Table 1.

[0100] Table 1: Nuclear magnetic resonance (CD3OD) data of compounds (+)-1, (+)-2, and 3

[0101]

[0102] Compounds (+)-1, (+)-2 and 3 have the same planar structure. Careful analysis of their 2D NMR (COSY, HSQC and HMBC) spectra revealed that the two amino acid residues that make them up include a proline and a methionine sulfoxide.

[0103] The absolute configurations of compounds (+)-1, (+)-2, (+)-3, and (-)-3 were determined by total synthesis. By comparing the optical rotation, NMR, and ECD data of the natural products (+)-1, (+)-2, (+)-3, and (-)-3 with those of the synthesized products, the absolute configurations of compounds (+)-1, (+)-2, (+)-2, and (-)-3 were ultimately determined to be 3R, 6R, 12R; (+)-2 to be 3R, 6R, 12S; and (+)-3 and (-)-3 to be 3R, 6S, 12S and 3S, 6R, 12R, respectively. Example 2

[0104] like Figure 19 The total synthetic routes for compounds (+)-1, (+)-2, (+)-3, and (-)-3, as well as four other possible optical isomers, are shown below.

[0105] The first step was the separation of diastereomers: The commercially available synthetic precursors were a mixture of two pairs of diastereomers, Fmoc-L-MetO [(S)-Fmoc-L-MetO and (R)-Fmoc-L-MetO] and Fmoc-D-MetO [(S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO]. We used supercritical CO2 chromatography to perform chiral separation of the two pairs of diastereomers, Fmoc-L-MetO and Fmoc-D-MetO.

[0106] Through column selection and mobile phase optimization, baseline separation was successfully achieved using a semi-preparative Chiralpak IC-3 column on a Waters SFC Prep 15 system. After comparison with literature data and X-ray single-crystal diffraction experiments, the four optically pure monomeric compounds were identified as: (S)-Fmoc-L-MetO (2.3 g, t... R =7.807 min), (R)-Fmoc-L-MetO (2.5 g, t R = 9.007 min), (S)-Fmoc-D-MetO (2.5 g, t R = 10.807 min) and (R)-Fmoc-D-MetO (2.0 g, t R = 12.179 min).

[0107] The structures of compounds (S)-Fmoc-L-MetO, (R)-Fmoc-L-MetO, (S)-Fmoc-D-MetO, and (R)-Fmoc-D-MetO are shown below:

[0108]

[0109] The physicochemical properties and nuclear magnetic resonance data of the synthetic precursor units (S)-Fmoc-L-MetO, (R)-Fmoc-L-MetO, (S)-Fmoc-D-MetO, and (R)-Fmoc-D-MetO obtained through the above steps are as follows:

[0110] (S)-Fmoc-L-MetO: White powdery solid, mp. 180-181 °C; HR-ESI-MS m / z: 388.1225 [M + H] +(calcd for C 20 H 22 NO5S: 388.1223); 1 H NMR (600 MHz, DMSO-d6): δ H 7.84 (2H,d, J = 7.6 Hz), 7.74-7.64 (2H, m), 7.37 (2H, t, J = 7.4 Hz), 7.33 (2H, td, J= 7.5, 2.0 Hz), 4.32-4.24 (2H, m), 4.18 (1H, t, J = 7.1 Hz), 4.03 (1H, td, J= 8.7, 4.8 Hz), 2.77-2.63 (2H, m), 2.50 (3H, s), 2.06 (1H, m), 1.91 (1H, m); 13 C NMR (150 MHz, DMSO-d6): δ C 173.1, 156.2, 143.8, 143.8, 140.8, 127.7, 127.1, 125.3, 120.2, 65.7, 53.1, 49.8, 46.7, 38.1, 24.3.

[0111] (R)-Fmoc-L-MetO: White powdery solid, mp. 179-180 °C; HR-ESI-MS m / z: 388.1219 [M + H] + (calcd for C 20 H 22 NO5S 388.1223); 1 H NMR (600 MHz, DMSO-d6): δ H 7.87 (2H, d, J = 7.5 Hz), 7.76-7.66 (2H, m), 7.40 (2H, t, J = 7.5 Hz), 7.31 (2H, td, J = 7.4, 1.4 Hz), 4.29 (2H, d, J = 7.0 Hz), 4.21 (1H, t, J = 7.1Hz), 4.07 (1H, m), 2.82 (1H, m), 2.63 (1H, m), 2.50 (3H, s), 2.10 (1H, m), 1.95 (1H, m); 3 C NMR (150 MHz, DMSO-d6): δ C173.1, 156.2, 143.8, 143.8, 140.7, 127.7, 127.1, 125.3, 120.2, 120.1, 65.7, 52.8, 49.5, 46.7, 37.8, 23.7.

[0112] (S)-Fmoc-D-MetO: White needle-like crystals (CH2Cl2: MeOH = 1:1); mp. 179-180 °C; HR-ESI-MS m / z: 388.1225 [M + H] + (calcd for C 20 H 22 NO5S: 388.1223); 1 H NMR (600 MHz, DMSO-d6): δ H 7.88 (2H, d, J = 7.5 Hz), 7.77-7.68 (2H, m), 7.41 (2H, t, J = 7.5Hz), 7.32 (2H, td, J = 7.4, 1.4 Hz), 4.30 (2H, d, J = 7.0 Hz), 4.22 (1H, t, J= 7.1 Hz), 4.08 (1H, td, J = 9.0, 4.4 Hz), 2.83 (1H, m), 2.64 (1H, m), 2.52(3H, s), 2.11 (1H, m), 1.96 (1H, m); 13 C NMR (150 MHz, DMSO-d6): δ C 173.1,156.1, 143.8, 143.8, 140.7, 127.7, 127.1, 125.3, 120.1, 120.1, 65.6, 52.8,49.5, 46.7, 37.8, 23.7.

[0113] (R)-Fmoc-D-MetO: White needle-like crystals (CH2Cl2: MeOH = 1:1); mp. 180-181 °C; HR-ESI-MS m / z: 388.1225 [M + H] + (calcd for C 20 H 22 NO5S: 388.1223); 1 H NMR (600 MHz, DMSO-d6): δ H7.89 (2H, d, J = 7.5 Hz), 7.79-7.70 (2H, m), 7.42 (2H, td, J =7.4, 1.2 Hz), 7.33 (2H, td, J = 7.4, 1.3 Hz), 4.31 (2H, d, J = 7.8 Hz), 4.23(1H, t, J = 7.0 Hz), 4.09 (1H, td, J = 8.7, 4.8 Hz), 2.75 (2H, m), 2.55 (3H,s), 2.12 (1H, m), 1.95 (1H, m); 13 C NMR (150 MHz, DMSO-d6): δ C 173.1, 156.1, 143.8, 143.8, 140.7, 127.7, 127.1, 125.3, 120.1, 65.7, 53.1, 49.8, 46.7, 38.1, 24.2.

[0114] Single-crystal data for compounds (S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO are shown in Table 2:

[0115] Table 2: Single crystal data of compounds (S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO

[0116]

[0117] The second step is condensation: the optically pure synthetic precursors obtained after separation are condensed with L-proline methyl ester and D-proline methyl ester respectively. The condensation reagent is dicyclohexylcarbodiimide (DCC), and the reaction process is monitored by TLC.

[0118] Weigh (R)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol), (R)-Fmoc-D-MetO (0.38 g, 3.0 mmol), (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol), and (S)-Fmoc-L-MetO (0.38 g, 3.0 mmol) into eight 50 mL round-bottom flasks, labeled 1-8. Measure 10 mL of dichloromethane and dissolve it completely. Add Et3N (0.30 g, 3 mmol) and DCC (0.74 g, 3.6 mmol) to the round-bottom flask at 0 °C. After stirring for 5 min, add L-proline methyl ester salt (1.16 g, 3.0 mmol) to round-bottom flasks 1, 4, 6, and 7, and D-proline methyl ester salt (1.16 g, 3.0 mmol) to round-bottom flasks 2, 3, 5, and 8. React overnight at room temperature and monitor by TLC. After the reaction, wash with saturated brine, extract three times with dichloromethane, and dry the organic layer with anhydrous Na2SO4. The crude product is purified by silica gel column chromatography (petroleum ether / ethyl acetate = 95:5) to give intermediate A1-H1 (1.3 g, 90.0% yield).

[0119] Step 3, Fmoc deprotection: using a 20% piperidine DMF solution (V 哌啶 V DMF = 1 : 4) Perform Fmoc deprotection;

[0120] Weigh 0.50 g (1.0 mmol) of Al-H1 into a 50 mL round-bottom flask, and add 20% piperidine DMF solution (V) at room temperature. 哌啶 V DMF = 1 : 4), after 30 min, the reaction was detected by TLC to be complete, and the reaction solution was evaporated to dryness to obtain a pale yellow solid.

[0121] Step 4, cyclization: Head-to-tail cyclization was performed using the polar organic solvent MeOH. The reaction was carried out at room temperature for 24 hours. After the reaction was completed by TLC, the compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 were obtained by purification.

[0122] 20 mL of the polar solvent methanol was added to the system, and the reaction was carried out at 80 °C for 24 hours. After the reaction was confirmed to be complete by TLC, the reaction solution was evaporated to dryness under vacuum. The product was purified by silica gel column chromatography (petroleum ether / ethyl acetate = 90:10) to obtain the target products (+)-1 (0.08 g, 34.7%), (-)-1 (0.07 g, 30.4%), (+)-2 (0.08 g, 34.7%), (-)-2 (0.08 g, 34.7%), (+)-3 (0.07 g, 30.4%), (-)-3 (0.07 g, 30.4%), (+)-4 (0.07 g, 30.4%), and (-)-4 (0.09 g, 39.1%).

[0123] Comparison of optical rotation, NMR, and ECD data confirmed that the synthesized compounds (+)-1, (+)-2, (+)-3, and (-)-3 completely matched the naturally isolated compounds (+)-1, (+)-2, (+)-3, and (-)-3. Figure 1 , 5 As shown in 9, 13~18. Figure 1 This is a schematic diagram comparing the ECD of natural product (+)-1 and synthetic product (+)-1. Figure 5 This is a schematic diagram comparing the ECD of the natural product (+)-5 and the synthetic product (+)-5. Figure 9 This is a schematic diagram comparing the ECD values ​​of the natural products (+)-3 and (-)-3 with those of the synthetic products (+)-3 and (-)-3. Figure 15 and 16 It is (+)-2 and the synthetic product (+)-2 1 H NMR and 13 Schematic diagram of C NMR comparison. Figure 17 and 18 It is the natural products (+)-3 and (-)-3 and the synthetic products (+)-3 and (-)-3. 1 H NMR and 13 Schematic diagram of C NMR comparison.

[0124] The structures of compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 are shown below:

[0125]

[0126] The physicochemical properties and nuclear magnetic resonance data of the synthetic products (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 obtained through the above steps are as follows:

[0127] (+)-1: White needle-like crystals (MeOH); mp. 142-143 °C; [α]25 D +4.6 (c 0.25, CH3OH); HR-ESI-MS m / z: 245.0954 [M + H] + (calcd for C 10 H 17 N2O3S: 245.0954); 1 H NMR (600 MHz, CD3OD): δ H 4.45 (1H, d, J = 5.4 Hz), 4.36 (1H, t, J = 7.9 Hz), 3.65-3.56 (2H, m), 3.03 (2H, m), 2.76 (3H, s), 2.44-2.33 (3H, m), 2.15-1.95 (3H,m); 13 C NMR (150 MHz, CD3OD): δ C 172.6, 167.1, 60.3, 55.1, 49.9, 46.4, 38.2,29.2, 23.8, 23.5; CD (CH3OH) λ max nm (Δε): 213 (1.85), 231 (-1.40).

[0128] (-)-1: White needle-like crystals (MeOH); mp. 142-143 °C; [α]25 D -4.4 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0762 [M + Na] + (calcd for C 10 H 16 N2O3SNa: 267.0774); 1 HNMR (600 MHz, CD3OD): δ H 4.42 (1H, d, J = 5.4 Hz), 4.37-4.29 (1H, m), 3.64-3.52(2H, m), 3.00 (2H, m), 2.73 (3H, s), 2.40-2.29 (3H, m), 2.12-1.92 (3H, m); 13 CNMR (150 MHz, CD3OD): δ C172.7, 167.2, 60.4, 55.1, 49.9, 46.4, 38.2, 29.2, 23.9, 23.5; CD(CH3OH) λ max nm (Δε): 214 (3.15), 231 (1.64).

[0129] (+)-2: White solid; mp. 147 - 148 °C; [α]25 D +6.2 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0763 [M + Na] + (calcd for C 10 H 16 N2O3SNa: 267.0774); 1 H NMR (600 MHz, CD3OD): δ H 4.40 (1H, d, J = 5.2 Hz), 4.31 (1H, t, J = 7.8 Hz), 3.64 - 3.52 (2H, m), 3.07 (1H, m), 2.92 (1H, m), 2.71 (3H, s), 2.35 (3H, m), 2.13 - 1.91 (3H, m); 13 C NMR (150 MHz, CD3OD): δ C 172.7, 167.2, 60.4, 55.3, 49.8, 46.5, 38.0, 29.3, 23.8, 23.5; CD(CH3OH) λ max nm (Δε): 214 (3.15), 231 (1.64); CD(CH3OH) λ max nm (Δε): 218 (-1.47), 233 (1.15).

[0130] (-)-2: White solid; mp. 147 - 148 °C; [α]25 D -6.1 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0777 [M + Na] + (calcd for C 10 H 16 N2O3SNa: 267.0774); 1 H NMR (600 MHz, CD3OD): δ H4.48 (1H, td, J = 5.1, 1.8 Hz), 4.38 (1H, m), 3.70 - 3.59 (2H, m), 3.15 (1H, m), 3.05 - 2.94 (1H, m), 2.79 (3H, s), 2.42 (3H, m), 2.20 - 1.97 (3H, m); 13 13C NMR (150 MHz, CD3OD): δ C 172.6, 167.1, 60.3, 55.2, 49.7, 46.4, 38.0, 29.2, 23.8, 23.5; CD (CH3OH) λ max nm (Δε): 211 (-0.42), 233 (-1.09).

[0131] (+)-3: White solid; mp. 143 - 144 °C; [α]25D +6.1 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0777 [M + Na] + (calcd for C 10 H 16 N2O3SNa 267.0774); 1 1H NMR (600 MHz, CD3OD): δ H 4.42 (1H, dd, J = 10.0, 6.5 Hz), 4.09 (1H, dd, J = 8.0, 6.2 Hz), 3.75 - 3.68 (1H, m), 3.61 (1H, m), 3.09 (1H, m), 2.99 (1H, m), 2.68 (3H, s), 2.50 - 2.39 (1H, m), 2.37 - 2.24 (2H, m), 2.13 (1H, m), 2.09 - 1.94 (2H, m); 13 13C NMR (150 MHz, CD3OD): δ C 171.1, 167.2, 59.3, 57.6, 50.5, 46.7, 38.2, 29.9, 28.0, 22.9; CD (CH3OH) λ max nm (Δε): 218 (4.14).

[0132] (-)-3: White solid; mp. 143 - 144 °C; [α]25 D -6.1 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0782 [M + Na] + (calcd for C 10 H 16 N2O3SNa 267.0774); 1 1H NMR (600 MHz, CD3OD): δ H 4.42 (1H, dd, J = 9.9, 6.4 Hz), 4.09 (1H, dd, J = 7.9, 6.3 Hz), 3.71(1H, m), 3.61 (1H, m), 3.09 (1H, m), 2.99 (1H, m), 2.78 (3H, s), 2.49 - 2.39(1H, m), 2.32 (2H, m), 2.17 - 2.10 (1H, m), 2.04 (2H, m); 13 13C NMR (150 MHz, CD3OD): δ C 171.2, 167.2, 59.3, 57.6, 50.4, 46.8, 38.2, 29.9, 28.0, 22.9; CD(CH3OH) λ max nm (Δε): 219 (-4.93).

[0133] (+)-4: White solid; mp. 141 - 142 °C; [α]25 D +5.4 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0777 [M + Na] + (calcd for C 10 H 16 N2O3SNa 267.0774); 1 1H NMR (600 MHz, CD3OD): δ H4.32 (1H, dd, J = 9.9, 6.5 Hz), 4.01-3.94 (1H, dd, J = 7.9, 6.4 Hz), 3.65-3.56 (1H, m), 3.51 (1H, m), 2.99 (1H, m), 2.86 (1H, m), 2.67 (3H, s), 2.41-2.31 (1H, m), 2.28-2.14 (2H, m), 2.04 (1H, m), 1.99-1.90 (2H, m); 13 C NMR (150 MHz, CD3OD): δ C 171.2, 167.3, 59.3, 57.6, 50.6, 46.8, 38.3, 29.9, 28.0,23.0; CD (CH3OH) λ max nm (Δε): 211 (3.24).

[0134] (-)-4: White solid; mp. 141-142 °C; [α]25 D +5.4 (c 0.25, CH3OH); HR-ESI-MS m / z: 267.0772 [M + Na] + (calcd for C 10 H 16 N2O3SNa 267.0774); 1 H NMR (600 MHz, CD3OD): δ H 4.33 (1H, dd, J = 10.1, 6.4 Hz), 4.02 (1H, dd, J = 8.0, 6.4 Hz), 3.60 (1H, m), 3.52 (1H, m), 3.01 (1H, m), 2.89 (1H, m), 2.69 (3H, s), 2.35(1H,m), 2.23(2H,m), 2.04(1H,m), 1.98-1.87(2H,m); 13 C NMR (150 MHz, CD3OD): δ C 171.2, 167.2, 59.3, 57.5, 50.4, 46.7, 38.3, 29.8, 27.9, 22.9; CD(CH3OH) λ max nm (Δε): 211 (-3.55).

[0135] Single-crystal data for compounds (+)-1 and (-)-1 are shown in Table 3:

[0136] Table 3: Single crystal data of compounds (S)-Fmoc-D-MetO and (R)-Fmoc-D-MetO

[0137] Example 3

[0138] In vitro activity experiments of compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4 and (-)-4 of the present invention.

[0139] Experimental protocol: Samples (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 were administered at a concentration of 50 μM, and MPTP was administered at a working concentration of 50 μM. Zebrafish juveniles (1 day post-fertilization, 1 dpf) were molted and placed in 6-well plates, with 30 fish randomly placed in each well. Four groups were established: blank group, model group, DMSO control group, and sample A-H+ MPTP group. The control group was treated with 5 mL of 1×E3 fish culture water. The model group was treated with 5 mL of 50 μM MPTP. The treatment group was treated with 5 mL of 50 μM plus 50 μM MPTP. Each group was treated continuously for 5 dpf. On day 5, zebrafish from different groups were sequentially transferred to 48-well cell culture plates for behavioral analysis, with a detection time of 20 min. Data processing was performed using Zeblab software to calculate the total swimming distance and swimming speed of zebrafish in a 48-well cell culture plate.

[0140] Experimental Results: This experiment evaluated the anti-Parkinson's disease effects of samples (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4. The results are as follows: Compared with the control group, the model group showed a significant decrease in movement speed and a marked reduction in movement distance, indicating successful model establishment. Compared with the model group, the co-treatment of samples (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 with MPTP significantly restored the locomotion ability of zebrafish, as evidenced by a significant increase in total movement distance and average movement speed, demonstrating statistically significant differences.

[0141] like Figure 20 This displays the behavioral performance of juvenile zebrafish. In the control group, the zebrafish swam within the normal range in terms of speed and distance during the behavioral experiment; compared to the control group, the zebrafish in the model group exhibited impaired behavior, displaying Parkinson's-like behaviors characteristic of motor dysfunction. (Compared to the control group, *××* P < 0.0001; compared with the model group,#### P<0.001, ### P<0.001, ## P<0.01, # P < 0.02.

[0142] The zebrafish in the co-treatment groups of samples (+)-1, (-)-1, (+)-3, (+)-4 and (-)-4 with MPTP showed significantly improved movement speed and total distance compared with the model group. Among them, samples (+)-1 and (-)-1 showed the best effect in improving MPTP-induced kinetic impairment.

[0143] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. An active sponge cyclic peptide compound, which is a cyclic dipeptide, characterized in that: It includes two amino acid fragments, namely proline and methionine sulfoxide.

2. The active sponge cyclic peptide compound according to claim 1, characterized in that: Its chemical structural formula is one of the following compounds: 。 3. A method for extracting sponge cyclic peptide alkaloids, characterized in that: Includes the following steps: Step 1: Extraction: After the sponge sample is dried and pulverized, it is extracted by percolation with an organic solvent. The extracts are combined and concentrated under reduced pressure to obtain the total extract. Step 2: Extraction: The total extract is suspended in water and extracted 3 to 5 times with equal volumes of petroleum ether, ethyl acetate and n-butanol respectively. The extracts are combined and concentrated under reduced pressure to obtain the n-butanol extract phase. Step 3: Separation: The n-butanol extract from step 2 was subjected to silica gel column chromatography with gradient elution using CH2Cl2-CH3OH eluent to obtain 6 fractions (Frs.1~6). Frs.5 was further separated using mass spectrometry with Sephadex LH-20 to obtain 5 fractions (Frs.5-1~5-5). Step 4: Mass spectrometry-guided separation: Based on the fragment ion information and chromatographic retention behavior obtained, Frs.5-3 was further separated and purified by HPLC to obtain the target compound.

4. The method for extracting sponge cyclic peptide alkaloids according to claim 3, characterized in that: The sponge sample in step 1 is a sponge. Dysidea sp., the organic solvent is any one of ethanol, methanol, or propanol.

5. The method for extracting sponge cyclic peptide alkaloids according to claim 3, characterized in that: The silica gel column chromatography method in step 3 is as follows: dichloromethane:methanol = 100:0, 100:1, 100:3, 100:5, 100:7, 100:10, 100:15, 100:20, 100:30, 100:50, 50:50, 0:100; The elution conditions for Sephadex LH-20 are: dichloromethane:methanol = 1:1, and a dropping rate of 5 seconds / drop. The HPLC separation conditions in step 4 are as follows: the molecular ion peak at 267.07 is detected in positive ion mode; Compounds (+)-1, (+)-2, and 3 were obtained by using CH3OH / H2O=10:90, flow rate 8 mL / min, and detection wavelength 210 nm on a YMC-PackODS-A column. Chiral column was used for further separation of 3. The mobile phase ratio of the chiral column was CH3OH / H2O=100:0, the flow rate was 0.6 mL / min, and the detection wavelength was 210 nm, to obtain optically pure enantiomers (+)-3 and (-)-3.

6. A method for synthesizing sponge cyclic peptide alkaloids, characterized in that: Includes the following steps: Step 1: Separate the two pairs of diastereomers to obtain the monomeric compounds: ( S )-Fmoc- L -MetO,( R )-Fmoc- L -MetO,( S )-Fmoc- D -MetO and ( R )-Fmoc- D -MetO; Step 2: Mix the monomeric compounds obtained in Step 1 with... L -proline methyl ester and D -Proline methyl ester undergoes condensation; Step 3: Fmoc deprotection: Fmoc deprotection was performed using a 20% piperidine DMF solution; Step 4: Cyclolysis: Head-to-tail cyclization was performed using the polar organic solvent MeOH. The reaction was carried out at room temperature for 24 hours. After the reaction was completed by TLC, the compounds (+)-1, (-)-1, (+)-2, (-)-2, (+)-3, (-)-3, (+)-4, and (-)-4 were obtained by purification.

7. The method for extracting sponge cyclic peptide alkaloids according to claim 6, characterized in that: The diastereomers in step 1 are as follows: Fmoc- L -MetO: [( S )-Fmoc- L -MetO and ( R )-Fmoc- L -MetO]; Fmoc- D -MetO: [( S )-Fmoc- D -MetO and ( R )-Fmoc- D -MetO]; Using the chromatographic column ChiralpakIC-3(5) μ The mobile phase ratio was MeOH / CO2 / 0.1%TFA=55 / 45, and the flow rate was 5.0 mL / min, for separation.

8. The method for extracting sponge cyclic peptide alkaloids according to claim 6, characterized in that: Step 2 includes: Weigh ( R )-Fmoc- L -MetO, ( S )-Fmoc- D -MetO, ( R )-Fmoc- L -MetO, ( S )-Fmoc- D -MetO, ( R )-Fmoc- D -MetO, ( S )-Fmoc- L -MetO, ( R )-Fmoc- D -MetO, ( S )-Fmoc- L -MetO was placed in eight round-bottom flasks, and dichloromethane was measured and completely dissolved in each flask. Add Et3N and DCC to the above round-bottom flasks at 0°C, stir for 5 minutes, and then add to round-bottom flasks No. 1, 4, 6, and 7. L -proline methyl ester salt, added to round-bottom flasks No. 2, 3, 5, and 8. D -proline methyl ester salt; The reaction was carried out overnight at room temperature and detected by TLC. After the reaction was completed, the mixture was washed with saturated brine, extracted three times with dichloromethane, and the organic layer was dried with anhydrous Na2SO4 and then evaporated to dryness to obtain the crude product. The crude product was purified by silica gel column chromatography (petroleum ether / ethyl acetate = 95:5) to obtain intermediate product A1-H1; In step 3, A1-H1 is weighed into a round-bottom flask and 20% piperidine DMF solution is added at room temperature (V 哌啶 V DMF = 1: 4), slowly raise the temperature to 80 ℃, react for 30 min, and after TLC detection of complete reaction, evaporate the reaction solution to dryness to obtain a pale yellow solid.

9. The method for extracting sponge cyclic peptide alkaloids according to claim 8, characterized in that: In step 4, the polar solvent is methanol; After the reaction was confirmed to be complete by TLC, the reaction solution was evaporated to dryness under vacuum and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 90:10) to obtain the target compound.

10. The application of the spongy cyclic peptide alkaloids as described in claim 1 in anti-Parkinson's drugs, characterized in that, The sponge cyclic peptide compounds are used to improve the movement speed of diseased zebrafish.

Images