(2S)-5-methoxy-7-hydroxyflavane as well as preparation method and application thereof

Abstract

The invention discloses (2S)-5-methoxy-7-hydroxyflavane as well as a preparation method and application thereof, and relates to the technical field of drug development, the chemical structural formula of the (2S)-5-methoxy-7-hydroxyflavane is as shown in formula (I), and the molecular formula is C16H16O3; according to the (2S)-5-methoxy-7-hydroxyflavane as well as the preparation method and the application thereof, a pharmacological experiment shows that within a dosage range of 25-100mg / kg, the (2S)-5-methoxy-7-hydroxyflavane can obviously improve the cardiac function of a mouse suffering from acute myocardial ischemia, the LVEF is increased by 37.2%-62.8%, the heart-weight ratio is reduced by 23.6%-41.3%, the serum CK-MB and cTn I levels are respectively reduced by 58.7% and 64.2%, and the (2S)-5-methoxy-7-hydroxyflavane can be used for treating acute myocardial ischemia. HE staining of cardiac muscle tissues shows that myocardial cells of a high-dose group of (2S)-5-methoxy-7-hydroxyflavane are arranged in order, and the nuclear fixation and shrinkage phenomenon is obviously reduced.

Description

Technical Field

[0001] This invention relates to drug development technology, specifically to a (2S)-5-methoxy-7-hydroxyflavone, its preparation method, and its application. Background Technology

[0002] *Daemonorops draco*, commonly known as dragon's blood, is a perennial evergreen vine belonging to the genus *Daemonorops* in the family Arecaceae. Its stems can reach 10-20 meters in length, densely covered with sharp thorns. It has pinnate compound leaves with linear-lanceolate leaflets. The fruit is a reddish-brown drupe, 2-3 cm in diameter, with yellow scales on the surface and containing a deep red liquid resin that dries into a blood clot-like structure. The resin is a valuable traditional Chinese medicine, sweet and salty in taste and neutral in nature. It is used to promote blood circulation, relieve pain, remove blood stasis, stop bleeding, and promote tissue regeneration. Clinically, it is used for injuries from falls and blows, swelling and pain due to blood stasis, external bleeding, and slow-healing sores. Modern research shows that it contains components such as daemonoropsin and daemonoropsin red, which can inhibit platelet aggregation and prevent thrombosis. It is also effective for upper gastrointestinal bleeding and angina pectoris.

[0003] Existing anti-myocardial ischemia drugs have the following drawbacks: First, their efficacy is limited, and the improvement in cardiac systolic function is insufficient, with the left ventricular ejection fraction (LVEF) improvement rate generally below 15%. Second, long-term use can easily lead to safety issues such as bleeding tendency. Third, their mechanisms of action are singular, lacking effective interventions for ventricular remodeling, making it difficult to achieve comprehensive reconstruction of myocardial function. These drawbacks mean that existing treatment options cannot meet the dual needs of patients with acute myocardial ischemia for rapid cardiac function recovery and long-term prognosis improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a (2S)-5-methoxy-7-hydroxyflavone, its preparation method and application, in order to solve the shortcomings of existing technologies such as limited efficacy, safety issues such as bleeding tendency caused by long-term use, and single mechanism of action.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a (2S)-5-methoxy-7-hydroxyflavone, the chemical structural formula of which is shown in formula (I), and the molecular formula is C. 16 H 16 O3, CAS number 35290-20-1;

[0006] The (2S)-5-methoxy-7-hydroxyflavone is derived from the fruit of the palm family, Euphorbia tirucalli.

[0007] The purity of the (2S)-5-methoxy-7-hydroxyflavone is ≥99.2%;

[0008]

[0009] A method for preparing (2S)-5-methoxy-7-hydroxyflavone includes the following steps;

[0010] S1. After the dried fruit of the dragon's blood was crushed, it was extracted twice by reflux with 95% ethanol, 75% ethanol and 50% ethanol in sequence to obtain the extract. The extracts were then filtered and combined.

[0011] S2. The solvent of the combined extract obtained in S1 is recovered under reduced pressure to obtain the draconis alcohol extract. The draconis alcohol extract is dispersed in water and extracted with petroleum ether and ethyl acetate in sequence to obtain the petroleum ether extract fraction, ethyl acetate extract fraction and water fraction.

[0012] S3. The ethyl acetate fraction in S2 was separated by silica gel column chromatography, and gradient elution was performed sequentially using a mixed solvent of petroleum ether-ethyl acetate and dichloromethane-methanol. The initial volume ratio of petroleum ether-ethyl acetate was 10:1 and was gradually adjusted to 0:1, and the initial volume ratio of dichloromethane-methanol was 8:1 and was gradually adjusted to 0:1. Eighteen separated fractions were collected and numbered sequentially as Fr.A to R.

[0013] S4. The Fr.C obtained in S3 was separated by silica gel column chromatography, and eluted sequentially with a mixed solvent of petroleum ether-ethyl acetate and methanol. The initial volume ratio of petroleum ether-ethyl acetate was 15:1 and was gradually adjusted to 0:1 to obtain 5 separated components, which were numbered Fr.C1 to C5 in sequence.

[0014] S5. The Fr.C3 obtained in S4 was separated by elution with a Sephadex LH-20 gel column using methanol-dichloromethane at a volume ratio of 1:1 to obtain three separate components, which were numbered Fr.C3a to C3c in sequence.

[0015] S6. The Fr.C3c obtained in S5 was subjected to gradient elution with a methanol-water mixed solvent on an ODS column. The initial volume ratio of methanol to water was 50:50 and was gradually adjusted to 95:5 to obtain (2S)-5-methoxy-7-hydroxyflavone.

[0016] Furthermore, in S1, the amount of ethanol used at each concentration is 1.5-2 times the weight of the *Dracaena cochinchinensis* fruit (L / kg), and the extraction time is 2 hours per extraction.

[0017] Furthermore, the petroleum ether-ethyl acetate gradient change rate is 10% decrease in petroleum ether per 100 mL;

[0018] The dichloromethane-methanol gradient has a rate of decrease of 12.5% ​​dichloromethane per 150 ml.

[0019] The application of a (2S)-5-methoxy-7-hydroxyflavone in the treatment of acute myocardial ischemia, the drug exerts its therapeutic effect by increasing left ventricular ejection fraction, reducing heart weight ratio and serum myocardial injury markers;

[0020] The dosage is 25-100 mg / kg / day.

[0021] Furthermore, cardiac function indicators include LVEF, LVFS, LVAW (d / s), LVPW (d / s), and LVID (d / s).

[0022] Serum markers of myocardial injury include CK-MB and cTnI;

[0023] Inflammatory infiltration markers include iNOS.

[0024] Compared with the prior art, the present invention provides a (2S)-5-methoxy-7-hydroxyflavone, its preparation method and application. Pharmacological experiments show that, within the dosage range of 25-100 mg / kg, (2S)-5-methoxy-7-hydroxyflavone can significantly improve cardiac function in mice with acute myocardial ischemia, increasing LVEF by 37.2%-62.8%, reducing the heart-to-body weight ratio by 23.6%-41.3%, and decreasing serum CK-MB and cTnI levels by 58.7% and 64.2%, respectively. HE staining of myocardial tissue shows that myocardial cells in mice in the high-dose (2S)-5-methoxy-7-hydroxyflavone group are neatly arranged and nuclear condensation is significantly reduced. IF staining of myocardial tissue shows that (2S)-5-methoxy-7-hydroxyflavone significantly reduces inflammatory cell infiltration and inflammation expression. At the same dose, (2S)-5-methoxy-7-hydroxyflavone improves the cure rate of acute myocardial ischemia, and this monomer has been found to have anti-acute myocardial ischemia effect for the first time, filling the gap in the prior art. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0026] Figure 1 A flowchart of mouse experiments provided for embodiments of the present invention;

[0027] Figure 2 These are initial ultrasound detection results for different treatment groups provided in embodiments of the present invention;

[0028] Figure 3 Detailed initial ultrasound detection data for different treatment groups provided in embodiments of the present invention;

[0029] Figure 4 A graph showing the effect of different treatment groups on cardiac function in mice with acute myocardial ischemia after 3 days of administration, according to an embodiment of the present invention;

[0030] Figure 5 The graph shows the serum CK-MB concentration in mice with acute myocardial ischemia after 3 days of administration to different treatment groups provided in this embodiment of the invention.

[0031] Figure 6 This is a graph showing the serum cTnI concentration in mice with acute myocardial ischemia after 3 days of administration to different treatment groups according to embodiments of the present invention.

[0032] Figure 7 HE staining results of mice with acute myocardial ischemia 3 days after administration of different treatment groups provided in the embodiments of the present invention;

[0033] Figure 8 The results of IF staining of the expression of the inflammatory marker iNOS in the myocardial tissue of mice with acute myocardial ischemia after 3 days of administration to different treatment groups provided in the embodiments of the present invention. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0035] Example 1:

[0036] A (2S)-5-methoxy-7-hydroxyflavone, the chemical structure of which is shown in formula (I), has a molecular formula of C2. 16 H 16 O3, CAS number 35290-20-1;

[0037] (2S)-5-methoxy-7-hydroxyflavone is derived from the fruit of the palm family, Euphorbia tirucalli.

[0038] (2S)-5-methoxy-7-hydroxyflavone purity ≥ 99.2%;

[0039]

[0040] The specific implementation method is to mix (2S)-5-methoxy-7-hydroxyflavone with a pharmaceutically acceptable carrier to prepare tablets, capsules, injections or lyophilized powder injections.

[0041] Example 2:

[0042] A method for preparing (2S)-5-methoxy-7-hydroxyflavone includes the following steps;

[0043] S1. After the dried fruit of the dragon's blood was crushed, it was extracted twice by reflux with 95% ethanol, 75% ethanol and 50% ethanol in sequence to obtain the extract. The extracts were then filtered and combined.

[0044] S2. The solvent of the combined extract obtained in S1 is recovered under reduced pressure to obtain the draconis alcohol extract. The draconis alcohol extract is dispersed in water and extracted with petroleum ether and ethyl acetate in sequence to obtain the petroleum ether extract fraction, ethyl acetate extract fraction and water fraction.

[0045] S3. The ethyl acetate fraction in S2 was separated by silica gel column chromatography, and gradient elution was performed sequentially using a mixed solvent of petroleum ether-ethyl acetate and dichloromethane-methanol. The initial volume ratio of petroleum ether-ethyl acetate was 10:1 and was gradually adjusted to 0:1, and the initial volume ratio of dichloromethane-methanol was 8:1 and was gradually adjusted to 0:1. Eighteen separated fractions were collected and numbered sequentially as Fr.A to R.

[0046] S4. The Fr.C obtained in S3 was separated by silica gel column chromatography, and eluted sequentially with a mixed solvent of petroleum ether-ethyl acetate and methanol. The initial volume ratio of petroleum ether-ethyl acetate was 15:1 and was gradually adjusted to 0:1 to obtain 5 separated components, which were numbered Fr.C1 to C5 in sequence.

[0047] S5. The Fr.C3 obtained in S4 was separated by elution with a Sephadex LH-20 gel column using methanol-dichloromethane at a volume ratio of 1:1 to obtain three separate components, which were numbered Fr.C3a to C3c in sequence.

[0048] S6. The Fr.C3c obtained in S5 was subjected to gradient elution with a methanol-water mixed solvent on an ODS column. The initial volume ratio of methanol to water was 50:50 and was gradually adjusted to 95:5 to obtain (2S)-5-methoxy-7-hydroxyflavone.

[0049] In S1, the amount of ethanol used at each concentration is 1.5-2 times the weight of the dragon fruit (L / kg), and the extraction time is 2 hours per extraction.

[0050] Petroleum ether-ethyl acetate gradient, with a rate of change of 10% petroleum ether per 100 ml;

[0051] Dichloromethane-methanol gradient, with a rate of decrease of 12.5% ​​dichloromethane per 150 ml.

[0052] The reagents used for extraction and separation, including ethanol, methanol, petroleum ether, ethyl acetate, and dichloromethane, were purchased from Beijing Chemical Plant and were all of analytical grade. The reagents used for high performance liquid chromatography, including acetonitrile and methanol, were of chromatographic grade and were produced by Thermo Fisher Scientific, Inc., USA. The water used was ultrapure water.

[0053] The analytical high-performance liquid chromatography column was Eclipseplus C18 (250×4.6mm, 5μm; Agilent Technologies, USA). The hydroxypropyl dextran gel for column chromatography, Sephadex LH-20, was manufactured by GE Amersham Biosciences, Sweden. The ODSC18 silica gel (40-63μm) was manufactured by Merck, Germany. The silica gel for column chromatography (200-300 mesh) and the GF254 silica gel pre-prepared plates for thin-layer chromatography (TLC) were both manufactured by Qingdao Marine Chemical Plant.

[0054] The dried fruit of Daemonorops draco Bl. was collected in Medan, Indonesia in September 2017 and identified by Professor Tu** of the School of Pharmaceutical Sciences, Peking University as the dried fruit of Daemonorops draco Bl. of the Arecaceae family. The sample specimen (XJ20170929) is stored at the Center for Modern Research of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Beijing University of Chinese Medicine.

[0055] 4.1 kg of dried dragon's blood fruit was initially pulverized and then extracted twice by refluxing with 8 L of 95% ethanol, 75% ethanol and 50% ethanol, 2 h each time. The extracts were filtered while hot, the filtrates were combined and the solvent was recovered under reduced pressure to obtain 1.2 kg of dragon's blood alcohol extract. 1.1 kg of the extract was dispersed in water and extracted with petroleum ether and ethyl acetate, respectively. Finally, 24.6 g of petroleum ether extract, 682.7 g of ethyl acetate extract and 368.9 g of water fraction were obtained. 500 g of ethyl acetate fraction was separated by silica gel column chromatography by elution with a gradient of petroleum ether-ethyl acetate (10:1→0:1) and dichloromethane-methanol (8:1→0:1), and a total of 18 fractions (Fr.A~R) were obtained.

[0056] Fr.C2 3.8g was separated by silica gel column chromatography, eluted sequentially with petroleum ether-ethyl acetate (15:1→0:1) and methanol, to obtain five fractions Fr.C1~C5. Fr.C3 3.2g was separated by Sephadex LH-20 gel column chromatography with methanol-dichloromethane 1:1, to obtain fractions Fr.C3a~C3c. Fr.C3c 2.1g was separated by ODS column chromatography, eluted with methanol-water (50:50→95:5), to obtain (2S)-5-methoxy-7-hydroxyflavone 1.0g.

[0057] Example 3,

[0058] The application of a (2S)-5-methoxy-7-hydroxyflavone in the treatment of acute myocardial ischemia, the drug exerts its therapeutic effect by increasing left ventricular ejection fraction, reducing heart weight ratio and serum myocardial injury markers;

[0059] The dosage is 25-100 mg / kg / day.

[0060] Cardiac function indices include LVEF, LVFS, LVAW;d / s, LVPW;d / s, LVID;d / s;

[0061] Serum myocardial injury markers include CK-MB and cTnI;

[0062] Inflammatory infiltration markers include iNOS.

[0063] Example 4:

[0064] Please refer to Figure 1 :

[0065] 1. Experimental animals:

[0066] 50 male ICR mice weighing 25±2 g were selected for the experiment, with the license number of SCXK (Beijing) 2021-0006 (Beijing Vital River Laboratory Animal Technology Co., Ltd.). They were housed in the SPF-level barrier facility of the Experimental Animal Center of Beijing University of Chinese Medicine. Environmental parameters: constant temperature of 22±1 °C, relative humidity of 45±2%, 12h / 12h light-dark cycle, and free access to food and water. All animal care and experimental procedures were approved by the Animal Care and Use Committee of Beijing University of Chinese Medicine.

[0067] 2. Experimental medicinal materials:

[0068] (2S)-5-Methoxy-7-hydroxyflavane is derived from the ethyl acetate extraction part of Dracaena cochinchinensis. After separation, purification and identification, it is stored in the Modern Research Center of Chinese Medicine of Beijing University of Chinese Medicine. The positive control drug, aspirin enteric-coated tablets (National Medicine Approval No. H37023270, Chenxin Pharmaceutical Co., Ltd.), has clear treatment indications for myocardial infarction.

[0069] 3. Solvent preparation:

[0070] The solvent was prepared by dissolving (2S)-5-methoxy-7-hydroxyflavane powder in CMC-Na solution with ultrasonic assistance, abbreviated as 5-ME solvent, which was used for animal experiments.

[0071] 4. Method for establishing a mouse model of acute myocardial ischemia:

[0072] An acute myocardial ischemia model was established in mice by ligation of the left anterior descending coronary artery (LAD). After acclimatization in a SPF environment for 7 days, the experimental animals were anesthetized according to the following standardized procedure: First, the animals were anesthetized with 1% sodium pentobarbital (0.16 mL / 25 g) via intraperitoneal injection, fixed in a supine position, and the chest area was shaved (range: upper sternal border to xiphoid process, left midaxillary line to right midclavicular line), followed by double disinfection with iodine and alcohol. Endotracheal intubation was performed under cold light guidance, and the animals were connected to a small animal ventilator (parameters: respiratory rate 100 breaths / min, tidal volume 2.0 mL / kg, respiratory ratio 1:1). The chest was opened through the third and fourth intercostal spaces, and the heart was exposed by blunt dissection. The LAD was ligated with 7-0 sutures 1-1.5 mm below the left atrial appendage. The chest was closed with 5-0 sutures layer by layer. Postoperatively, the animals were placed on a constant-temperature electric blanket for monitoring until awakening. A sham surgery group was used as a control, undergoing only chest opening and suture insertion without ligation.

[0073] 5. Animal grouping and administration

[0074] After the mice recovered, they were randomly divided into four groups: a sham-operated group, a model group, a low-dose 5-ME-L group (25 mg / kg), a medium-dose 5-ME-M group (50 mg / kg), a high-dose 5-ME-H group (100 mg / kg), and a positive control group (39 mg / kg), with eight mice in each group. The causes of death and disposal methods for mice that died after LAD ligation and during feeding were recorded, and the bodies were disposed of in accordance with biosafety regulations and ethical requirements. Twenty-four hours after ligation, mice in the low-dose 5-ME-L group, medium-dose 5-ME-M group, and high-dose 5-ME-H group were administered 0.1 mL / 10 g of 2.5 g / L, 5 g / L, and 10 g / L 5-ME solvent via gavage. Mice in the positive control group were administered 3.9 g / L aspirin via gavage according to the same standard. Mice in the sham-operated and model groups were administered the same volume of CMC-Na solution via gavage for consistency. Administration was continued at a fixed time each day for 3 days.

[0075] Example 5: Based on Example 4, this example provides a technical solution: the effect of (2S)-5-methoxy-7-hydroxyflavone on cardiac function in mice with acute myocardial ischemia;

[0076] The ultrasound results 3 days after administration were as follows Figure 2 and Figure 3As shown, after 3 days of LAD treatment, compared with the sham-operated group, the LVEF and LVFS values ​​of mice in the model group were significantly decreased (P<0.0001), LVAW;d and LVAW;s were also decreased (P<0.01), while LVPW;d, LVID;d and LVID;s were increased (P<0.01). This indicates that the cardiac function of mice was impaired after LAD ligation, the ejection fraction was reduced, the myocardial contractility was decreased, and the anterior wall of the left ventricle was thinned, thus the mouse model of acute myocardial ischemia was successfully established. After three days of continuous administration of (2S)-5-methoxy-7-hydroxyflavone solvent, compared with the model group, the low-dose 5-ME-L group, the medium-dose 5-ME-M group, the high-dose 5-ME-H group, and the aspirin group significantly improved cardiac function in LAD mice, with significantly increased LVEF and LVFS values ​​(P<0.05), slightly upregulated LVAW;d and LVAW;s values ​​(P<0.05), and decreased LVPW;d, LVPW;s, LVID;d, and LVID;s values ​​to varying degrees. The efficacy of (2S)-5-methoxy-7-hydroxyflavone in treating acute myocardial ischemia was dose-dependent (P<0.05). The high-dose 5-ME-H group showed the most significant effect, superior to the medium-dose 5-ME-M group and the low-dose 5-ME-L group, and consistent with or even more significant than the positive control aspirin group. These results indicate that (2S)-5-methoxy-7-hydroxyflavone can significantly improve cardiac contractility and ejection capacity, increase cardiac output, and effectively improve cardiac function in mice with acute myocardial ischemia. Aspirin is clinically used to treat acute myocardial infarction and is widely used for the prevention and treatment of acute coronary syndrome. The results show that it can improve cardiac function in mice with acute myocardial infarction (P<0.05).

[0077] Example 6, based on Example 4, provides a technical solution: the effect of (2S)-5-methoxy-7-hydroxyflavone on the heart-to-body weight ratio in mice with acute myocardial ischemia:

[0078] Please see Figure 4 Heart-to-body weight ratio (HW / BW) is an important morphological indicator for evaluating cardiac function and ventricular remodeling. The heart-to-body weight ratio of mice in the model group was significantly higher than that of mice in the sham-operated group (P<0.0001), indicating that the infarct area of ​​mice in the model group was larger and cardiac function was impaired. The AMI model was successfully established. After 3 days of gavage administration of the low-dose 5-ME-L group, the medium-dose 5-ME-M group, the high-dose 5-ME-H group and the positive drug aspirin group, the ratio decreased in a dose-dependent manner (P<0.05), and the high dose showed a similar efficacy to the positive drug. This indicates that (2S)-5-methoxy-7-hydroxyflavone can effectively reduce the heart-to-body weight ratio, thereby resisting myocardial hypertrophy, inhibiting ventricular remodeling, and enhancing cardiac function.

[0079] Example 7, based on Example 4, provides a technical solution: the effect of (2S)-5-methoxy-7-hydroxyflavone on the levels of CK-MB and cTnI in the serum of mice with acute myocardial ischemia:

[0080] Please see Figure 5 and Figure 6 CK-MB and cTnI, as myocardial-specific markers, have high sensitivity and specificity and are important bases for the diagnosis of acute myocardial ischemia. ELISA results showed that the serum CK-MB and cTnI levels in the model group mice were significantly higher than those in the sham-operated group (P<0.0001), indicating that the myocardial ischemia model was successfully established and caused significant myocardial damage. After 3 days of gavage administration of the low-dose 5-ME-L group, the medium-dose 5-ME-M group, the high-dose 5-ME-H group, and the positive drug aspirin group, the CK-MB and cTnI levels were reduced to varying degrees compared with the model group (P<0.05), indicating that (2S)-5-methoxy-7-hydroxyflavone can reduce the serum CK-MB and cTnI levels in mice with acute myocardial infarction, alleviate myocardial damage, and improve cardiac function.

[0081] Example 8: This example provides a technical solution based on Example 4. Please refer to Example 8. Figure 7 HE staining results showed that the myocardial tissue structure in the sham surgery group was intact, with myocardial cells arranged in regular long columnar shapes, and the nuclei stained evenly in the center, with no obvious pathological changes. The model group, on the other hand, showed typical pathological features of myocardial infarction: disordered arrangement of myocardial cells, nuclear condensation and fragmentation, accompanied by significant inflammatory cell infiltration and destruction of myofibrillary structure. After intervention with (2S)-5-methoxy-7-hydroxyflavone, all dose groups could improve the above pathological changes, showing that the arrangement of myocardial cells tended to be regular, the morphology of the nuclei tended to be normal, and the inflammatory infiltration was reduced. The positive control aspirin group also showed a similar cardioprotective effect, which was comparable to that of (2S)-5-methoxy-7-hydroxyflavone.

[0082] Example 9: This example provides a technical solution based on Example 4. Please refer to Example 4 for details. Figure 8The IF results showed that the sham-operated group had uniform cell nuclei, neatly arranged cardiomyocytes, extremely low iNOS expression, and weak fluorescence signal. Compared with the sham-operated group, the model group showed significantly increased iNOS expression and strong fluorescence signal, indicating a severe inflammatory response after acute myocardial ischemia. After intervention with (2S)-5-methoxy-7-hydroxyflavone, the iNOS fluorescence intensity was lower than that in the model group. The fluorescence intensity of the low-dose 5-ME-L group was moderate, the fluorescence intensity of the medium-dose 5-ME-M group was slightly higher, but the distribution range was smaller, and the iNOS expression of the high-dose 5-ME-H group was significantly reduced, reaching the level of the aspirin group. This indicates that with the increase of the dose of (2S)-5-methoxy-7-hydroxyflavone, iNOS expression and inflammatory cell infiltration gradually weakened, showing a significant inhibitory effect on inflammatory cell infiltration.

[0083] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A (2S)-5-methoxy-7-hydroxyflavone, characterized in that, Its chemical structural formula is shown in formula (I), and its molecular formula is C. 16 H 16 O3, CAS number 35290-20-1; The (2S)-5-methoxy-7-hydroxyflavone is derived from the fruit of the palm family, Euphorbia tirucalli. The purity of the (2S)-5-methoxy-7-hydroxyflavone is ≥99.2%.

2. A method for preparing (2S)-5-methoxy-7-hydroxyflavone, characterized in that, Includes the following steps; S1. After the dried fruit of the dragon's blood was crushed, it was extracted twice by reflux with 95% ethanol, 75% ethanol and 50% ethanol in sequence to obtain the extract. The extracts were then filtered and combined. S2. The solvent of the combined extract obtained in S1 is recovered under reduced pressure to obtain the draconis alcohol extract. The draconis alcohol extract is dispersed in water and extracted with petroleum ether and ethyl acetate in sequence to obtain the petroleum ether extract fraction, ethyl acetate extract fraction and water fraction. S3. The ethyl acetate fraction in S2 was separated by silica gel column chromatography, and gradient elution was performed sequentially using a mixed solvent of petroleum ether-ethyl acetate and dichloromethane-methanol. The initial volume ratio of petroleum ether-ethyl acetate was 10:1 and was gradually adjusted to 0:1, and the initial volume ratio of dichloromethane-methanol was 8:1 and was gradually adjusted to 0:

1. Eighteen separated fractions were collected and numbered sequentially as Fr.A to R. S4. The Fr.C obtained in S3 was separated by silica gel column chromatography, and eluted sequentially with a mixed solvent of petroleum ether-ethyl acetate and methanol. The initial volume ratio of petroleum ether-ethyl acetate was 15:1 and was gradually adjusted to 0:1 to obtain 5 separated components, which were numbered Fr.C1 to C5 in sequence. S5. The Fr.C3 obtained in S4 was separated by elution with a Sephadex LH-20 gel column using methanol-dichloromethane at a volume ratio of 1:1 to obtain three separate components, which were numbered Fr.C3a to C3c in sequence. S6. The Fr.C3c obtained in S5 was subjected to gradient elution with a methanol-water mixed solvent on an ODS column. The initial volume ratio of methanol to water was 50:50 and was gradually adjusted to 95:5 to obtain (2S)-5-methoxy-7-hydroxyflavone.

3. The method for (2S)-5-methoxy-7-hydroxyflavone according to claim 2, characterized in that, In S1, the amount of ethanol used at each concentration is 1.5-2 times the weight of the *Dracaena cochinchinensis* fruit (L / kg), and the extraction time is 2 hours per extraction.

4. The method for (2S)-5-methoxy-7-hydroxyflavone according to claim 2, characterized in that: The petroleum ether-ethyl acetate gradient change rate is 10% decrease in petroleum ether per 100 ml. The dichloromethane-methanol gradient has a rate of decrease of 12.5% ​​dichloromethane per 150 ml.

5. The use of (2S)-5-methoxy-7-hydroxyflavone as described in claim 1 in the treatment of acute myocardial ischemia, characterized in that, The drug exerts its therapeutic effect by increasing left ventricular ejection fraction, reducing cardiac weight, serum myocardial injury markers, and cardiac inflammatory cell infiltration; The dosage is 25-100 mg / kg / day.

6. The application according to claim 5, characterized in that: Cardiac function indicators include LVEF, LVFS, LVAW; d / s, LVPW; d / s, LVID; d / s; Serum markers of myocardial injury include CK-MB and cTnI; Indicators of cardiac immune infiltration include the inflammatory marker iNOS.

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