A class of ligustrazine derivatives of NO donor type, preparation method, composition and use

Abstract

The application discloses a NO donor type ligustrazine derivative, a preparation method, a composition and application, and provides a NO donor type ligustrazine derivative and a preparation method thereof, and further provides a composition of different dosage forms prepared by mixing the NO donor type ligustrazine derivative or a pharmaceutically acceptable salt thereof and a pharmaceutical excipient, and application of the composition in preparation of a medicine for preventing or treating thromboembolic cardiovascular and cerebrovascular diseases and diseases caused by platelet aggregation.

Description

Technical Field

[0001] This invention relates to the field of medicinal chemistry, specifically to a class of NO donor-type tetramethylpyrazine derivatives, their preparation methods, compositions, and uses. Background Technology

[0002] Cardiovascular disease is the leading cause of death worldwide. Among cardiovascular diseases, ischemic heart disease alone causes more deaths than all cancers combined. Thrombi formed from various causes can lead to myocardial infarction, stroke, and pulmonary embolism, causing a sudden reduction in blood supply to the corresponding organs and tissues, resulting in thrombosis-related cardiovascular and cerebrovascular diseases. Myocardial infarction and stroke are common cardiovascular and cerebrovascular diseases, characterized by high morbidity, high mortality, and high disability rates, seriously endangering human health.

[0003] Currently, the main drugs used in clinical practice for the prevention and treatment of thrombosis-related cardiovascular and cerebrovascular diseases include thrombolytic drugs, anticoagulants, and antiplatelet aggregation drugs. Among them, antiplatelet aggregation drugs targeting arterial thrombosis are the most widely used, applied in both the treatment and prevention of thromboembolism. Representative drugs include cyclooxygenase inhibitors such as aspirin, P2Y12 receptor inhibitors such as clopidogrel, and ticagrelor.

[0004] Tetramethylpyrazine (TMP) is an alkaloid isolated from the medicinal plant Ligusticum chuanxiong. It is one of the most important active components of Ligusticum chuanxiong, possessing a wide range of cardiovascular and cerebrovascular pharmacological activities, including vasodilation, endothelial protection, antiplatelet aggregation, and anti-oxidative stress. Clinically, it is often used in ischemic cardiovascular and cerebrovascular diseases to dilate blood vessels, reduce ischemic damage, and improve prognosis. However, due to its rapid oxidation in vivo, TMP suffers from a short half-life, low bioavailability, weak efficacy, requiring frequent administration, and a tendency to accumulate and cause toxicity. Pharmacokinetic and structural modification studies of TMP have shown that the pyrazine ring in the parent nucleus is the pharmacodynamic group that determines its pharmacological effects. Modifying the side chain of TMP while retaining the pyrazine ring can yield TMP derivatives with better efficacy and superior pharmacokinetic properties.

[0005] Nitric oxide (NO) is an important gaseous messenger molecule. In the early stages of ischemic injury or ischemia-reperfusion injury, NO can regulate vascular tone, maintain normal blood vessel and tissue perfusion, inhibit platelet aggregation and adhesion, and suppress the release of inflammatory factors, thereby protecting ischemic tissues. NO donors, serving as storage and transport forms of NO in vivo and in vitro, can release NO in vivo through enzymatic or non-enzymatic processes, thus increasing its stability after entering the body and prolonging its release half-life. Common NO donors include nitrates, nitrites, azodium glycol salts, furazolidone N-oxides, and nitrosothiols.

[0006] Introducing a NO donor into the structure of a tetramethylpyrazine derivative to synthesize a NO donor-type tetramethylpyrazine derivative, which releases NO and the tetramethylpyrazine derivative in vivo, yields a novel drug that simultaneously possesses nitric oxide molecular activity and tetramethylpyrazine activity. This drug is expected to exert effects such as antiplatelet aggregation and adhesion, vasodilation, and reduction of ischemia-reperfusion injury, thereby better preventing and treating thromboembolic cardiovascular and cerebrovascular diseases. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of the above-mentioned technologies and provide a class of NO donor-type tetramethylpyrazine derivatives, preparation methods, compositions and uses.

[0008] To solve the above-mentioned technical problems, the present invention provides a NO donor-type tetramethylpyrazine derivative, wherein the derivative comprises a tetramethylpyrazine intermediate core, an active group, a linker arm, and a NO donor structure, and its general structural formula is shown in Formula I:

[0009]

[0010] Where X is the linker arm, selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl or such alkyl structures; where R is the NO donor structure, selected from nitrate esters.

[0011] Furthermore, the structural formula of the derivative is any one of Formula II:

[0012]

[0013] Furthermore, its reaction pathway is as follows:

[0014]

[0015] Where X is selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl or such alkyl structures.

[0016] Furthermore, the composition comprises a NO donor-type tetramethylpyrazine derivative or a pharmaceutically acceptable salt thereof, and the composition is a drug in a different dosage form prepared from a NO donor-type tetramethylpyrazine derivative or a pharmaceutically acceptable salt thereof and pharmaceutical excipients.

[0017] Furthermore, the composition is used in the preparation of medicaments for the prevention or treatment of thromboembolic cardiovascular and cerebrovascular diseases.

[0018] Furthermore, the use of the composition in the preparation of medicaments for the prevention or treatment of diseases caused by platelet aggregation.

[0019] Furthermore, the disease refers to any one of the following: arteriosclerosis, thrombotic stroke, transient ischemic attack, coronary heart disease, or myocardial infarction.

[0020] The advantages of this invention compared to existing technologies are as follows: This invention provides a class of NO donor-type tetramethylpyrazine derivatives and their preparation methods. It also provides compositions of different dosage forms made from NO donor-type tetramethylpyrazine derivatives or their pharmaceutically acceptable salts and pharmaceutical excipients, and the application of these compositions in the preparation of drugs for the prevention or treatment of thromboembolic cardiovascular and cerebrovascular diseases and diseases caused by platelet aggregation. Specifically, this invention provides nine compounds, five of which, in in vitro experiments inhibiting ADP and AA-mediated platelet aggregation, showed that compound TN-1 exhibited good inhibitory activity, superior to tetramethylpyrazine monomer, superior to tetramethylpyrazine intermediate T1, and superior to control compound T2. Attached Figure Description

[0021] Figure 1 This is the result of the inhibitory effect of some of the compositions of the present invention on ADP-mediated platelet aggregation in vitro, *p<0.05vs TMP, n=5.

[0022] Figure 2 This is the result of the inhibitory effect of some of the compositions of the present invention on AA-mediated platelet aggregation in vitro, *p<0.05 vs TMP, n=5 Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Unless otherwise specified, the equipment and reagents used in the embodiments and experimental examples are commercially available. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0024] Based on the information contained in this application, various changes to the precise description of the invention can be readily made by those skilled in the art without departing from the spirit and scope of the appended claims. It should be understood that the scope of the invention is not limited to the defined processes, properties, or components, as these embodiments and other descriptions are merely illustrative of specific aspects of the invention. In fact, various modifications to embodiments of the invention that will be apparent to those skilled in the art or related fields are covered within the scope of the appended claims.

[0025] To better understand the invention and not to limit its scope, all figures indicating amounts, percentages, and other numerical values ​​used in this application should, in all cases, be understood to be modified by the word "about". Therefore, unless specifically stated otherwise, the numerical parameters listed in the specification and appended claims are approximate values ​​and may vary depending on the desired properties being sought. Each numerical parameter should at least be considered as obtained based on reported significant figures and through conventional rounding methods. In this invention, "about" means within 10%, preferably within 5%, of a given value or range.

[0026] Unless otherwise specified, the following embodiments of the present invention are all under normal temperature conditions. Normal temperature refers to the natural room temperature conditions in all four seasons, without additional cooling or heating treatment. Generally, the normal temperature is controlled between 10 and 30°C, preferably between 15 and 25°C.

[0027] Unless otherwise stated, the following terms used in the specification and claims have the meanings discussed below:

[0028] "alkyl" includes, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, and n-hexyl.

[0029] The term "pharmaceutically acceptable salt" as used in this invention refers to salts that retain the bioavailability and properties of the parent compound. Such salts include:

[0030] (1) It forms salts with acids, which are obtained by reacting the free base of the parent compound with inorganic or organic acids. Inorganic acids include hydrochloric acid, hydrobromic acid, nitric acid, phosphoric acid, metaphosphoric acid, sulfuric acid, sulfurous acid and perchloric acid, etc. Organic acids include acetic acid, trifluoroacetic acid, propionic acid, acrylic acid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic acid, oxalic acid, (D) or (L) malic acid, fumaric acid, tartaric acid, maleic acid, ascorbic acid, benzoic acid, hydroxybenzoic acid, γ-hydroxybutyric acid, methoxybenzoic acid, phthalic acid, methanesulfonic acid, camphoric acid, oxalic acid, ethanesulfonic acid, naphthalene-1-sulfonic acid, naphthalene-2-sulfonic acid, p-toluenesulfonic acid, salicylic acid, tartaric acid, citric acid, lactic acid, cinnamic acid, dodecyl sulfate, gluconic acid, glutamic acid, aspartic acid, stearic acid, mandelic acid, succinic acid or malonic acid, etc.

[0031] (2) Salts formed by replacing acidic protons in the parent compound with metal ions or by coordinating with organic bases. Examples of metals include alkali metal ions, alkaline earth metal ions, or aluminum ions. Examples of organic bases include ethanolamine, diethanolamine, triethanolamine, tromethamine, N-methylglucosamine, quinine, etc.

[0032] In this invention, "pharmaceutical composition" refers to the mixture of one or more of the compounds of this invention, or their pharmaceutically acceptable salts, solvates, hydrates, or prodrugs, with other chemical components, such as pharmaceutically acceptable excipients. The purpose of the pharmaceutical composition is to facilitate the administration to animals.

[0033] In this invention, "pharmaceutical excipients" refers to inactive ingredients in pharmaceutical compositions that do not cause significant irritation to the organism and do not interfere with the biological activity and properties of the given compound. Examples include, but are not limited to: calcium carbonate, calcium phosphate, various sugars (e.g., lactose, mannitol, etc.), starch, cyclodextrin, magnesium stearate, cellulose, magnesium carbonate, acrylic polymers or methacrylic polymers, gels, water, polyethylene glycol, propylene glycol, ethylene glycol, castor oil or hydrogenated castor oil or polyethoxylated hydrogenated castor oil, sesame oil, corn oil, peanut oil, etc.

[0034] This invention provides a pharmaceutical composition having the compound, isomer, or pharmaceutically acceptable salt thereof described in this invention as the active ingredient or the main active ingredient, supplemented with a pharmaceutically acceptable salt. The active ingredient of this pharmaceutical composition may be solely the compound of this invention, or it may be used in combination with other existing pharmaceutical products.

[0035] In this invention, when administering mammalian compounds of formula I and their pharmaceutically acceptable salts, as well as solvates of these compounds (collectively referred to herein as "therapeutic drugs"), they may be used alone or preferably in combination with a suitable pharmaceutical carrier or diluent according to standard pharmaceutical methods. Administration can be via various routes, including oral, non-gastrointestinal, or local administration. Non-gastrointestinal administration, as referred to herein, includes, but is not limited to, intravenous, intramuscular, intraperitoneal, subcutaneous, and transdermal administration.

[0036] The compounds, isomers, or pharmaceutically acceptable salts thereof of the present invention may be used to treat and / or prevent thromboembolic cardiovascular and cerebrovascular diseases, to treat and / or prevent diseases caused by platelet aggregation, or to treat or prevent ischemic diseases.

[0037] This invention discloses a class of NO donor-type tetramethylpyrazine derivatives, their preparation methods, pharmaceutical compositions, and uses. The technical solution of this invention will be clearly and completely described below with reference to embodiments.

[0038] Example 1

[0039] In this embodiment, a total of 9 compounds were synthesized, referred to as TN-1 to TN-9 respectively.

[0040] Compound TN-1 is named 2-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-2-nitrooxyethyl ester, and its structural formula is as follows:

[0041]

[0042] Compound TN-2 is named 3-(E)-(3-(3,5,6-trimethylpyrazin-2-yl)acryloyloxy)benzoic acid-2-nitrooxyethyl ester, and its structural formula is as follows:

[0043]

[0044] Compound TN-3 is named 4-(E)-(3-(3,5,6-trimethylpyrazin-2-yl)acryloyloxy)benzoic acid-2-nitrooxyethyl ester, and its structural formula is as follows:

[0045]

[0046] Compound TN-4 is named 2-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-4-nitrooxybutyl ester, and its structural formula is as follows:

[0047]

[0048] Compound TN-5 is named 3-(E)-(3-(3,5,6-trimethylpyrazin-2-yl)acryloyloxy)benzoic acid-4-nitrooxybutyl ester, and its structural formula is as follows:

[0049]

[0050] Compound TN-6 is named 4-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-4-nitrooxybutyl ester, and its structural formula is as follows:

[0051]

[0052] Compound TN-7 is named 2-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-6-nitrooxyhexyl ester, and its structural formula is as follows:

[0053]

[0054] Compound TN-8 is named 3-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-6-nitrooxyhexyl ester, and its structural formula is as follows:

[0055]

[0056] Compound TN-9 is named 4-(E)-(3-(3,5,6-trimethylpyrazine-2-yl)acryloyloxy)benzoic acid-6-nitrooxyhexyl ester, and its structural formula is as follows:

[0057]

[0058] The reaction route involved in this embodiment of the invention is as follows:

[0059]

[0060] Step a: Weigh ligustrazine trihydrate (20.4 g, 107 mmol), dissolve it in 30 ml of glacial acetic acid, add 30% hydrogen peroxide solution (12.1 ml, 107 mmol), and react at 90 °C for 2 h. Then add 30% hydrogen peroxide (12 ml, 107 mmol) and continue the reaction for 2 h. After the reaction is complete as monitored by TLC, cool the reaction solution to room temperature. Under ice-water bath, adjust the pH of the reaction solution to 10 with 50% sodium hydroxide solution. At this time, a large amount of white solid will precipitate. Add dichloromethane for extraction (150 ml, 50 ml × 3 times), dry with anhydrous sodium sulfate for 4 h, filter the dichloromethane solution, and remove the solvent by rotary evaporation under reduced pressure to obtain white crude ligustrazine mononitroxide compound (1).

[0061] Step b: The crude tetramethylpyrazine mononitrate compound (13.8 g, 90.6 mmol) was placed in a single-necked flask, and acetic anhydride (17.1 ml, 181.2 mmol) was added. The mixture was then slowly heated to 140 °C and refluxed for 2.5 h. After the reaction was completed by TLC monitoring, a dark brown paste-like tetramethylpyrazine acetylated compound (2) was obtained.

[0062] Step c: Cool the dark brown paste-like tetramethylpyrazine acetylation (2) to room temperature, slowly add 20% sodium hydroxide solution (100 ml) under an ice-water bath, stir overnight (12 h) at room temperature, extract with dichloromethane (160 ml, 40 ml × 4 times), dry with anhydrous sodium sulfate for 4 h, filter the dichloromethane solution, and remove the solvent by rotary evaporation under reduced pressure to obtain a brownish-yellow crude 2-hydroxymethyl-3,5,6-trimethylpyrazine. Recrystallize the crude product with a mixed solvent of petroleum ether and ethyl acetate (PE:EA = 10:1, V / V) to give 5.5 g of pale yellow crystals, which is compound 3. The overall yield is 33.7%.

[0063] Step d: 2-Hydroxymethyl-3,5,6-trimethylpyrazine (3, 6.09 g, 40 mmol) was placed in a 50 mL single-necked flask, dissolved in anhydrous ethanol (20 mL), and activated manganese dioxide (20.8 g, 240 mmol) was added. The mixture was heated under reflux for 6 h. After the reaction was completed by TLC monitoring, a layer of filter paper was placed in a glass frit funnel, followed by an appropriate amount of diatomaceous earth (median particle size 13 μm, calcined) and another layer of filter paper. The mixture was poured into the reaction mixture and filtered. The filtrate was evaporated under reduced pressure to dryness to give 5.67 g of a yellow solid, which was compound 4, with a yield of 94.4%.

[0064] Step e: 3,5,6-Trimethylpyrazine-2-carboxaldehyde (4,5.50 g, 36.6 mmol) was placed in a 50 mL single-necked flask, and 50 mL of toluene was added. While stirring, sodium hydride (1.76 g, 73.2 mmol) was slowly added to the solution. The reaction flask was wrapped with aluminum foil, and triethyl phosphonoacetate (9.0 g, 40.3 mmol) was added dropwise. The reaction was carried out at room temperature in the dark for 8-10 h, and the reaction was monitored by TLC. After the reaction was complete, an equal volume of ethyl acetate was added for dilution, and the mixture was washed with brine (50 mL × 2 times). After separation, the mixture was dried over anhydrous sodium sulfate for 8 h, filtered, and the solvent was removed from the filtrate under reduced pressure to obtain crude (E)-3-(3,5,6-trimethylpyrazine-2-yl)acrylate. The crude product was purified by silica gel column chromatography (PE / EA = 8:1, V / V) to give 6.45 g of a bright yellow oil, which was compound 5, with a yield of 80.0%.

[0065] Step f: Ethyl (E)-3-(3,5,6-trimethylpyrazin-2-yl)acrylate (5, 6.45 g, 29.3 mmol) was dissolved in a mixed solution of tetrahydrofuran and water (V(THF) / V(H2O) = 2:1, 30 mL), and sodium hydroxide (2.35 g, 58.6 mmol) was added. The mixture was stirred at room temperature for 4 h, and the reaction was monitored by TLC until complete. After the reaction was complete, the pH of the reaction solution was adjusted to 3 with 2N hydrochloric acid, and solid sodium chloride was added until saturation. The mixture was extracted with ethyl acetate (50 mL × 3 times), and the combined organic phases were dried over anhydrous sodium sulfate for 8 h. The mixture was filtered, and the solvent was removed by rotary evaporation under reduced pressure to give 5.50 g of white solid, which was compound 6, with a yield of 97.8%.

[0066] Step g: Synthesis of intermediates 7a-i: Hydroxybenzoic acid (1.22 g, 5 mmol) was dissolved in 20 ml of acetone, and dibromoalkane (7.5 mmol, 1.5 eq) and triethylamine (0.76 g, 7.5 mmol, 1.5 eq) were added. The mixture was heated under nitrogen protection and refluxed for 5 h. After the reaction was completed, the mixture was cooled to room temperature and evaporated to dryness using a rotary evaporator. An appropriate amount of ethyl acetate was added and the mixture was stirred for 5 min. The mixture was filtered, and an appropriate amount of silica gel for column chromatography was added to the filtrate. The mixture was then evaporated to dryness and separated by column chromatography to obtain intermediates 7a-i.

[0067] 7a, separated by column chromatography (PE / EtOAc = 8 / 1, v / v), yielded 0.27 g of a colorless liquid, with a yield of 22.1%.

[0068] 7b, separated by column chromatography (PE / EtOAc = 8 / 1, v / v), yielded 0.33 g of a colorless liquid, with a yield of 27.1%.

[0069] 7c, separated by column chromatography (PE / EtOAc = 6 / 1, v / v) to give 0.36 g of white solid, yield 29.5%.

[0070] After 7 days, 0.83 g of a colorless oily substance was obtained by column chromatography (PE / EtOAc = 10 / 1, v / v), with a yield of 61.1%.

[0071] 7e was separated by column chromatography (PE / EtOAc = 8 / 1, v / v) to obtain 0.67 g of a colorless oil, with a yield of 49.3%.

[0072] 7f, separated by column chromatography (PE / EtOAc = 10 / 1, v / v) to obtain 0.80 g of colorless oil, yield 58.9%.

[0073] 7g was separated by column chromatography (PE / EtOAc = 10 / 1, v / v) to obtain 0.90g of colorless oil, with a yield of 59.8%.

[0074] After 7 hours, 1.35 g of a colorless oily substance was obtained by column chromatography (PE / EtOAc = 10 / 1, v / v), with a yield of 89.7%.

[0075] 7i, separated by column chromatography (PE / EtOAc = 10 / 1, v / v), yielded 0.59 g of a colorless oil, with a yield of 39.2%.

[0076] Step h: Synthesis of intermediates 8a-i: Compound 6 (0.19 g, 1 mmol) and DCC (0.23 g, 1.1 mmol) were dissolved in 20 mL of anhydrous dichloromethane, and a catalytic amount of DMAP (0.1 mmol) was added. The mixture was stirred at room temperature for 15 min. Then, intermediates 7a-i (1.1 mmol) were added, and the mixture was stirred at room temperature for 4-6 h. After the reaction was completed, the mixture was filtered, and the filtrate was evaporated to dryness using a rotary evaporator. An appropriate amount of ethyl acetate was added, and the mixture was stirred for 5 min. The mixture was filtered again, and an appropriate amount of silica gel for column chromatography was added to the filtrate. The mixture was then evaporated to dryness, and intermediates 10a-i were obtained by column chromatography.

[0077] 8a, separated by column chromatography (PE / EtOAc = 5 / 1, v / v), yielded 0.28 g of white powder, with a yield of 67.6%.

[0078] 8b, separated by column chromatography (PE / EtOAc = 5 / 1, v / v), yielded 0.29 g of white powder, with a yield of 70.0%.

[0079] 8c, separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to obtain 0.29 g of white powder, yield 70.0%.

[0080] After 8 days, a yellow viscous solid of 0.20 g was obtained by column chromatography (PE / EtOAc = 5 / 1, v / v), with a yield of 42.7%.

[0081] 8e was separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to give 0.41 g of a yellow viscous solid, with a yield of 92.7%.

[0082] 8f, separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to obtain 0.42 g of white flaky solid, yield 95.0%.

[0083] 8g was separated by column chromatography (PE / EtOAc = 4 / 1, v / v) to give 0.44g of white solid, yield 93.6%.

[0084] After 8 hours, a white solid of 0.46 g was obtained by column chromatography (PE / EtOAc = 4 / 1, v / v), with a yield of 98.0%.

[0085] 8i, separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to give 0.45 g of white solid, yield 95.8%.

[0086] Step i: Synthesis of target products TN-1 to TN-9: Intermediates 8a to i (1.0 eq) were dissolved in 20 ml of acetonitrile, AgNO3 (1.5 eq) was added, and the mixture was reacted at 70 °C for 3 to 4 h in the dark. After the reaction was completed, the mixture was filtered, and the filtrate was evaporated to dryness using a rotary evaporator. An appropriate amount of ethyl acetate was added, and the mixture was stirred for 5 min. The mixture was filtered again, and an appropriate amount of silica gel for column chromatography was added to the filtrate. The mixture was then evaporated to dryness, and the target products were obtained by column chromatography. Alternatively, the filtrate was concentrated and the target products TN-1 to TN-9 were obtained by preparing thin-layer chromatography plates.

[0087] TN-1 was separated by column chromatography (PE / EtOAc = 2 / 1, v / v) to obtain 0.10 g of a pale yellow viscous solid, with a yield of 37.2%.

[0088] TN-2 was separated by column chromatography (PE / EtOAc = 2 / 1, v / v) to obtain 0.08 g of a yellow viscous solid, with a yield of 64.3%.

[0089] TN-3 was separated by column chromatography (PE / EtOAc = 2 / 1, v / v) to obtain 0.06 g of a yellow viscous solid, with a yield of 49.8%.

[0090] TN-4 was separated by column chromatography (PE / EtOAc = 4 / 1, v / v) to obtain 0.03 g of a pale yellow viscous solid, with a yield of 38.8%.

[0091] TN-5 was separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to obtain 0.27 g of a pale yellow viscous solid, with a yield of 68.6%.

[0092] TN-6 was separated into 0.26 g of a yellow solid by thin-layer chromatography on a GF254 substrate (DCM / MeOH = 50 / 1, v / v), with a yield of 64.5%.

[0093] TN-7 was separated into a yellow oily substance of 0.25 g by thin-layer chromatography on a GF254 substrate (DCM / MeOH = 50 / 1, v / v), yielding 59.0%.

[0094] TN-8 was separated into 0.12 g of a yellow oil by column chromatography (PE / EtOAc = 5 / 1, v / v), with a yield of 27.1%.

[0095] TN-9 was separated into a yellow solid of 0.28 g by thin-layer chromatography on a GF254 substrate (DCM / MeOH = 50 / 1, v / v), yielding 64.7%.

[0096] All synthesized compounds were subjected to... 1 HNMR, 13 CNMR and HRMS spectral analysis confirmed the correct structure.

[0097] TN-1,2-(nitrooxy)ethyl(E)-2-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d): δ8.08(d,1H,J=6.4Hz,6-ArH),8.05(d,1H,J=15.6Hz,ArCH=CH),7.60(t,1H,J=7.8Hz,4-Ar H),7.36(t,1H,J=7.6Hz,5-ArH),7.31(d,1H,J=15.3Hz,ArCH=CH),7.19(d,1H,J=8.0Hz,3-ArH),4.38(t,2H,J=4.5Hz,CH2 CH2 NO3), 3.84(t, 2H, J = 4.5Hz, CH2 CH2NO3),2.66(s,3H,ArCH3),2.56(d,6H,J=5.9Hz,ArCH3); 13C NMR(151MHz,CDCl3)δ165.28,164.98,152.75,150.56,150.22,148.86,142.79,140.50,133.99,132.03,126.19,123.78,123.43,122.71,77.22,77.01,76.80,66.93,60.71,21.63,21.61,20.29;HRMS(ESI):m / z:402.1301calc.for C 19 H 20 N3O7[M+H] + ,found402.1291,ppm error-2.5.

[0098] TN-2,2-(nitrooxy)ethyl(E)-3-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d)δ8.03(d,1H,J=15.2Hz,ArCH=CH),7.96(d,1H,J=7.8Hz,6-ArH),7.86(s,1H,2-ArH),7.49(m,1H,J=7.9Hz,5-ArH),7.39(d,1H,J=8.1Hz,4-ArH),7.24(d,1H,J=15.3Hz,ArCH=CH),4.47(t,2H,J=4.6Hz,CH2CH2NO3),3.96(t,2H,J=4.6Hz,CH2CH2NO3),2.64(s,3H,ArCH3),2.55(s,6H,ArCH3); 13 CNMR(151MHz,CDCl3)δ165.93,164.95,153.15,150.68,150.26,149.17,142.28,140.95,131.41,129.49,127.12,126.51,122.89,121.88,77.22,77.01,76.80,66.90,61.19,21.95,21.71,20.58;HRMS(ESI):m / z:402.1301 calc.for C 19 H 20 N3O7[M+H] + ,found402.1300,ppm error-0.2.

[0099] TN-3,2-(nitrooxy)ethyl(E)-4-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d):δ8.12(d,2H,J=8.5Hz,2,6-ArH),8.03(d,1H,J=15.2Hz,Ar CH =CH),7.31-7.24(m,3H,3,5-ArH and ArCH= CH ),4.48(t,2H,J=4.7Hz,CH2 CH2 NO3),3.97(t,2H,J=4.6Hz, CH2 CH2NO3),2.67(s,3H,ArCH3),2.58(d,6H,J=7.2Hz,ArCH3); 13 C NMR(151MHz,CDCl3)δ166.11,164.47,154.54,152.61,150.83,148.59,142.77,140.60,131.29,127.43,122.34,121.63,77.21,77.00,76.79,66.77,61.33,21.71,21.52,20.12;HRMS(ESI):m / z:402.1301 calc.for C 19 H 20 N3O7[M+H] + ,found402.1299,ppm error-0.5.

[0100] TN-4,4-(nitrooxy)butyl(E)-2-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d)δ8.06(d,1H,J=14.7 Hz,Ar CH =CH),8.04(d,1H,J=7.9Hz,6-ArH),7.60(t,1H,J=7.8Hz,4-ArH),7.36(t,1H,J=7.7Hz,5-ArH),7.32(d,1H,J=15.2Hz,ArCH= CH),7.19(d,1H,J=8.1Hz,3-ArH),4.43(t,2H,J=5.9Hz,CH2NO3),4.30(t,2H,J=5.6Hz,COOCH2),2.65(s,3H,ArCH3),2.55(d,6H,J=5.6Hz,ArCH3),1.87–1.77(m,4H,CH2 CH2CH2 CH2); 13 C NMR(151MHz,CDCl3)δ165.17,164.62,153.10,150.39,150.23,149.14,142.28,140.79,133.91,131.78,126.11,123.84,123.52,122.00,77.22,77.01,76.79,72.53,64.18,24.99,23.62,21.97,21.70,20.58;HRMS(ESI):m / z:430.1614 calc.for C 21 H 24 N3O7[M+H] + ,found 430.1617,ppm error 0.7.

[0101] TN-5,4-(nitrooxy)butyl(E)-3-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate.

[0102] 1 H NMR(600MHz,Chloroform-d)δ8.04(d,1H,J=15.2Hz,Ar CH =CH),7.93(dt,1H,J=7.8,1.3Hz,6-ArH),7.83(t,1H,J=2.0Hz,2-ArH),7.50(t,1H,J=7.9Hz,5-ArH),7.40(ddd,1H,J=8.1,2.4,1.1Hz,4-ArH),7.26(d,1H,J=15.3Hz,ArCH= CH ),4.55–4.49(m,2H,CH2NO3),4.41–4.35(m,2H,COOCH2),2.65(s,3H,ArCH3),2.55(s,6H,ArCH3),1.91(m,4H,J=3.0Hz,CH2 CH2CH2 CH2); 13C NMR(151MHz,CDCl3)δ165.53,164.95,153.17,150.73,150.21,149.19,142.26,140.97,131.58,129.50,126.98,126.44,122.77,121.89,77.23,77.01,76.80,72.54,64.22,25.08,23.70,21.99,21.72,20.61;HRMS(ESI):m / z:430.1614calc.for C 21 H 24 N3O7[M+H] + ,found 430.1614,ppm error 0.0.

[0103] TN-6,4-(nitrooxy)butyl(E)-4-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate.

[0104] 1 H NMR(600MHz,Chloroform-d)δ8.10(d,2H,J=8.7Hz,2,6-ArH),8.04(d,1H,J=15.2Hz,Ar CH =CH),7.27(d,3H,J=8.2Hz,3,5-ArH and ArCH= CH ),4.57–4.50(m,2H,CH2NO3),4.38(m,2H,COOCH2),2.65(s,3H,ArCH3),2.56(s,6H,ArCH3),1.92(m,4H,J=3.3Hz,CH2 CH2CH2 CH2); 13 C NMR(151MHz,CDCl3)δ165.70,164.60,154.51,153.15,150.34,149.14,142.31,141.05,131.83,131.14,127.72,127.57,121.91,121.66,121.62,115.24,77.20,76.99,76.78,72.63,72.55,64.06,63.61,25.14,25.12,23.76,23.72,21.92,21.72,20.54;HRMS(ESI):m / z:430.1614 calc.for C 21 H 24 N3O7[M+H]+ ,found 430.1618,ppm error0.9.

[0105] TN-7,6-(nitrooxy)hexyl(E)-2-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d):δ8.01(d,1H,J=15.3Hz,Ar CH =CH),8.00(d,1H,J=8.5Hz,6-ArH),7.55(t,1H,J=7.7Hz,4-ArH),7.31(t,1H,J=6.8Hz,5-ArH),7.29(d,1H,J=15.4Hz,ArCH= CH ),7.15(d,1H,J=8.1Hz,3-ArH),4.34(t,2H,J=6.6Hz,CH2NO3),4.22(t,2H,J=6.6Hz,COOCH2),2.61(s,3H,ArCH3),2.51(d,6H,J=4.1Hz,ArCH3),1.65(m,4H,J=14.5,7.6Hz,CH2 CH2 CH2CH2 CH2 CH2),1.37(m,4H,J=11.7,10.4,6.8Hz,CH2CH2 CH2CH2 CH2CH2); 13 C NMR(151MHz,CDCl3)δ165.15,164.69,153.08,150.38,150.08,149.15,142.27,140.63,133.71,133.68,131.78,131.74,126.04,126.02,123.81,123.79,123.77,122.12,122.09,77.27,77.06,76.85,73.06,65.07,64.92,28.44,28.39,26.55,25.62,25.54,25.29,25.17,22.03,22.01,21.73,21.69,20.67,20.65;HRMS(ESI):m / z:458.1927calc.for C 23 H 28 N3O7[M+H] + ,found 458.1927,ppm error 0.0.

[0106] TN-8,6-(nitrooxy)hexyl(E)-3-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d)δ8.04(d,1H,J=15.3Hz,ArCH=CH),7.95(d,1H,J=7.8Hz,6-ArH),7.85–7.82(m,1H,2-ArH),7.50(t,1H,J=7.9Hz,5-ArH),7.39(dd,1H,J=8.1,1.3Hz,4-ArH),7.26(d,1H,J=15.3Hz,ArCH=CH),4.46(t,2H,J=6.6Hz,CH2NO3),4.34(t,2H,J=6.6Hz,COOCH2),2.69(s,3H,ArCH3),2.58(d,6H,J=13.3Hz,ArCH3),1.83–1.73(m,4H,CH2CH2CH2CH2CH2CH2),1.50(m,4H,J=3.6,2.7Hz,CH2CH2CH2CH2CH2CH2); 13 C NMR(151MHz,CDCl3)δ165.66,164.97,153.18,150.69,150.18,149.21,142.25,140.95,131.90,129.43,126.98,126.26,122.75,121.91,77.23,77.02,76.81,73.14,64.97,28.47,26.66,25.63,25.37,22.01,21.72,20.63;HRMS(ESI):m / z:458.1927calc.for C 23 H 28 N3O7[M+H] + ,found 458.1931,ppm error 0.9.

[0107] TN-9,6-(nitrooxy)hexyl(E)-4-((3-(3,5,6-trimethylpyrazin-2-yl)acryloyl)oxy)benzoate. 1 H NMR(600MHz,Chloroform-d)δ8.10(d,2H,J=8.6Hz,2,6-ArH),8.04(d,1H,J=15.3Hz,Ar CH=CH),7.29–7.25(m,3H,3,5-ArH and ArCH=CH),4.46(t,2H,J=6.7Hz,CH2NO3),4.34(t,2H,J=6.6Hz,COOCH2),2.65(s,3H,ArCH3),2.56(d,6H,J= 4.0Hz,ArCH3),1.78(m,4H,J=20.2,6.9Hz,CH2CH2CH2CH2CH2CH2),1.52–1.48(m,4H,CH2CH2CH2CH2CH2CH2); 13 C NMR (151MHz, CDCl3) δ165.81,164.61,154.38,153.24,150.20,149.23,142.19,141.08,131.10,127.87,121.82,121.58, 77.25,77.03,76.82,73.14,64.79,28.51,26.67,25.62,25.37,22.00,21.71,20.61; HRMS(ESI):m / z:458.1927calc.for C 23 H 28 N3O7[M+H] + ,found 458.1928,ppm error 0.2.

[0108] Example 2

[0109] In this embodiment, one compound was synthesized, abbreviated as T2, which is a pharmacological control compound for compounds TN-1, TN-2, TN-3, etc.

[0110] Compound T2 is named (E)-3-(3,5,6-trimethylpyrazine-2-yl)acrylate-2-nitrooxyethyl ester, and its structural formula is as follows:

[0111]

[0112] The reaction route involved in this embodiment of the invention is as follows:

[0113]

[0114] Step a: Synthesis of intermediate 9: 2-bromoethanol (10 mmol) was dissolved in 50 ml of acetonitrile, AgNO3 (2.55 g, 15 mmol) was added, and the mixture was reacted at 70 °C for 3 h in the dark. After the reaction was completed, the mixture was filtered, and the filtrate was evaporated to dryness using a rotary evaporator. An appropriate amount of ethyl acetate was added, and the mixture was stirred for 5 min. The mixture was then filtered and evaporated to dryness again to obtain 0.82 g of a light yellow liquid, which was intermediate 9, with a yield of 76.6%.

[0115] Step b: Compound 6 (0.74 g, 3.8 mmol) and DCC (0.79 g, 1.0 mmol) were dissolved in 30 mL of anhydrous dichloromethane. A catalytic amount of DMAP (0.1 mmol) was added, and the mixture was stirred at room temperature for 15 min. Then, intermediate 9 (3.5 mmol) was added, and the mixture was stirred at room temperature for 8 h. After the reaction was completed, the mixture was filtered, and the filtrate was evaporated to dryness using a rotary evaporator. An appropriate amount of ethyl acetate was added, and the mixture was stirred for 5 min. The mixture was filtered again, and an appropriate amount of silica gel for column chromatography was added to the filtrate. The mixture was then evaporated to dryness, and the filtrate was separated by column chromatography (PE / EtOAc = 5 / 1, v / v) to obtain 0.40 g of a white waxy solid, which was compound T2, with a yield of 47.0%. 1 H NMR (600MHz, Chloroform-d): δ7.88 (d, 1H, J = 15.3Hz, Ar CH =CH),7.06(d,1H,J=15.3Hz,ArCH=CH),4.79–4.72(m,2H,CH2CH2NO3),4.55–4.48(m,2H,CH2CH2NO3),2.62(s,3H,ArCH3),2.52(d,6H,J=4.6Hz,ArCH3); 13 C NMR (151MHz, CDCl3) δ166.28,153.01,150.02,149.12,142.25,140.06,121.87,77.20, 76.99,76.77,70.44,60.36,22.02,21.69,20.66; HRMS(ESI):m / z:281.1112calc.forC 12 H 15 N3O5[M+H] + ,found281.1109,ppm error-1.1.

[0116] Example 3: Antiplatelet aggregation pharmacological test and results of the representative compound of the present invention

[0117] The Born turbidimetric assay was used to determine the IC50 of different compounds on arachidonic acid (AA) or adenosine 5'-diphosphate (ADP)-mediated platelet aggregation. 50 The specific implementation method is as follows:

[0118] Preparation of platelet-rich plasma (PRP) and anemic platelet-rich plasma (PPP): Rabbits fasted for 12-18 hours were anesthetized by intraperitoneal injection of 20% urethane solution. The common carotid artery was separated, and blood was collected through a polyethylene tube. The blood was injected into a siliconized centrifuge tube containing 1 / 10 of its volume of 3.8% sodium citrate solution. The blood was gently mixed with anticoagulant and centrifuged at 1000 rpm for 15 minutes. The upper light yellow suspension was aspirated, which is approximately platelet-rich plasma (PRP). The remaining plasma was centrifuged at 3000 rpm for 15 minutes, and the supernatant was aspirated to obtain anemic platelet-rich plasma (PPP). PPP was used to adjust the platelet count of PRP to 1×10⁻⁶. 8 / mL.

[0119] Experimental drug groups: Positive control group: TMP; Experimental groups: T1, T2 (i.e., intermediate 6 in Example 1), TN-1, TN-2, TN-3, TN-4, TN-7. All drugs were set at 6 concentrations: 0.1, 0.2, 0.4, 0.8, 1.6, and 3.2 mmol / L.

[0120] Platelet aggregation rate was determined using the Born turbidimetric assay at 37°C. 260 μl of PRP was placed in a turbidimetric tube, followed by 10 μl of different concentrations of the test compound, positive control drug, or DMSO solution. The tubes were incubated at 37°C for 5 min, and then 30 μl of inducer was added sequentially. The final concentration of inducer ADP was 10 μM, and the final concentration of inducer AA was 1 mM. The maximum aggregation rate within 5 min was measured using a platelet aggregometer in both the control and test tubes. The inhibition rate of platelet aggregation was calculated as follows: Inhibition rate of platelet aggregation (IRPA) = (Platelet aggregation rate of control group - Platelet aggregation rate of experimental group) / Platelet aggregation rate of control group × 100%. The dose-response curve was plotted using GraphPadPrism software to obtain the IC50. 50 Data are expressed as mean ± SD. Statistical differences between groups were analyzed using one-way ANOVA and Tukey's test. A p-value less than 0.05 was considered statistically significant.

[0121] Table 1. Inhibitory effects of compounds on ADP / AA-induced platelet aggregation (Mean ± SD, n = 5, *P < 0.05 vs TMP.)

[0122]

[0123]

[0124] As shown in Table 1, compound TN-1 exhibits a good inhibitory effect on ADP-induced platelet aggregation, IC50... 50The value was 0.7736, which was significantly different from that of tetramethylpyrazine monomer; it also had a good inhibitory effect on AA-induced platelet aggregation, with an IC50 value of 0.7736. 50 The value was 0.6232, which was significantly different from that of tetramethylpyrazine monomer. This indicates that compound TN-1 has better antiplatelet aggregation activity, and its overall activity is superior to that of the original compound tetramethylpyrazine.

[0125] Preliminary analysis of the structure-activity relationship of the compounds revealed that the NO donor exhibited the best activity when attached to the ortho position on the benzene ring via a carbon chain, with activity decreasing sequentially when attached to the meta and para positions. The carbon chain length of the NO donor also affected the antiplatelet aggregation activity of the compounds; the activity was best when the carbon chain length was 2 carbons, decreasing sequentially with lengths of 4 and 6 carbons. To investigate the influence and contribution of the active group salicylic acid on the compound activity, we synthesized a control compound T2, whose structure consists of a tetramethylpyrazine intermediate and a NO donor. Antiplatelet aggregation experiments showed that its activity was significantly reduced compared to the tetramethylpyrazine monomer and compound TN-1, indicating that the salicylic acid structure has a significant impact on the activity of compound TN-1. To further illustrate the influence of the NO donor structure on the compound's activity, we also conducted experiments on the tetramethylpyrazine intermediate T1. The results showed that its activity was weakened in the ADP-induced antiplatelet aggregation experiment, while its activity was superior in the AA-induced antiplatelet aggregation experiment. Considering that T1 contains a free carboxylic acid structure, which may affect the antiplatelet aggregation experiment, it still preliminarily indicates that the NO donor structure contributes more to the AA-induced antiplatelet aggregation activity. Comprehensive analysis shows that the active group salicylic acid structure and the NO donor structure of compound TN-1 are both essential to its overall activity and play a role in enhancing the activity.

[0126] The present invention and its embodiments have been described above. This description is not restrictive, and the listed embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention. 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 present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A class of NO donor type tetrandrine derivatives, characterized in that, The derivative includes a ligustrazine intermediate parent nucleus, an active group, a connecting arm, and a NO donor structure, and a general structure thereof is shown as Formula I. X is a connecting arm, and is selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, and n-hexyl; R is a NO donor structure, and is selected from nitrate.

2. The class of NO-donor ligustrazine derivatives according to claim 1, characterized in that, The structural formula of the derivative is any one of the following: 。 3. The process for preparing a class of NO-donor ligustrazine derivatives according to any one of claims 1 or 2, characterized in that, A reaction route thereof is as follows: X is selected from any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, and n-hexyl.

4. A composition characterized in that, The application relates to a NO donor type ligustrazine derivative or a pharmaceutically acceptable salt thereof.

5. A composition characterized in that, The application relates to a NO donor type ligustrazine derivative or a pharmaceutically acceptable salt thereof and a medicine prepared by mixing the derivative or the salt with a pharmaceutical auxiliary material.

6. Use of the composition according to claim 4 in the preparation of a medicine for preventing or treating thromboembolic cardiovascular and cerebrovascular diseases.

7. Use of the composition according to claim 4 in the preparation of a medicine for preventing or treating diseases caused by platelet aggregation.

8. Use of a composition according to claim 6 or 7, characterized in that: The diseases refer to any one of atherosclerosis, thrombotic cerebral stroke, transient cerebral ischemia, coronary heart disease, and myocardial infarction.

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