A C 19 Diterpene alkaloids, processes for their preparation and uses thereof

Abstract

This invention discloses a C 19 Diterpenoid alkaloids, their preparation methods, and uses belong to the field of pharmaceutical technology. This C 19 The structures of the diterpenoid alkaloids are shown in Formula I. Pharmacological experiments showed that all compounds of the present invention possess cardiotonic effects. In particular, compared with the positive control arbutin, compounds 1, 2, 4, 7, and 10 of the present invention exhibited significantly enhanced cardiotonic effects. The compounds of the present invention can be used to prepare cardiotonic drugs, as well as drugs for the prevention and / or treatment of heart failure. The compounds of the present invention can be extracted and isolated from plants of the genus *Aconitum*, making them widely available and possessing broad clinical application and market potential.

Description

Technical fields:

[0001] This invention relates to the field of pharmaceutical technology, specifically to a C 19 Diterpenoid alkaloids, their preparation methods, and uses. Background technology:

[0002] Heart failure is a clinical syndrome resulting from the severe development of various cardiovascular diseases. Traditionally, heart failure is considered primarily due to abnormal myocardial contractility leading to a reduced cardiac output that cannot meet the body's needs, resulting in a series of symptoms and signs. Cardiac glycosides are among the most important medications for treating heart failure. Cardiac glycosides are divided into two categories: digitalis and non-digitalis drugs. Digitalis is the most commonly used drug in the treatment of heart failure, with a history of approximately 200 years. Digitalis selectively inhibits the production of sodium in myocardial cell membranes. + -K + -ATPase activity is mediated by biphasic Na+ + -Ca 2+ The exchange mechanism enables Ca 2+ Increased influx leads to increased intracellular calcium levels. 2+ Digitalis exerts a positive inotropic effect at high concentrations. However, it can cause various adverse reactions, including arrhythmias (such as premature ventricular contractions and conduction blocks), gastrointestinal symptoms (such as nausea and vomiting), and neurological disorders (such as dizziness and yellow / green vision). Non-digitalis drugs mainly include dopamine, dobutamine, amrinone, milrinone, and levosimendan. While increasing myocardial contractility, non-digitalis drugs can also accelerate the patient's heart rate and increase myocardial oxygen consumption, thereby aggravating myocardial ischemia. As myocardial ischemia worsens, myocardial contractility will decrease, leading to dependence on non-digitalis drugs and creating a vicious cycle.

[0003] Plants of the genus *Aconitum* in the family Ranunculaceae are an important group of plants with a long history of medicinal use. Abundant in resources, there are approximately 350 species worldwide, distributed in the temperate zones of the Northern Hemisphere, primarily in Asia, followed by Europe and North America. In my country, there are about 200 species of *Aconitum*, of which 76 are medicinal, mainly distributed in the Hengduan Mountains of southwest China, such as the high-altitude areas of northern Yunnan, western Sichuan, and eastern Tibet. The medicinal value of *Aconitum* plants is widely documented. For example, the 2020 edition of the *Chinese Pharmacopoeia* includes *Aconitum carmichaelii*, *Aconitum kusnezoffii*, and *Aconitum napellus*. *Aconitum carmichaelii* and *Aconitum kusnezoffii* have the effects of dispelling wind and dampness, warming the meridians and relieving pain, while *Aconitum napellus* has the effects of restoring yang, tonifying fire and assisting yang, and dispelling cold and relieving pain. Traditional Chinese medicine compound formulas with *Aconitum napellus* as the main ingredient, such as Fuzi Lizhong Wan and Si Ni Tang, are also included in the *Chinese Pharmacopoeia*, possessing the effects of warming the middle jiao and strengthening the spleen, dispelling cold, and restoring yang.

[0004]

[0005] Diterpenoid alkaloids are characteristic components of the Aconitum genus. Researchers have discovered that diterpenoid alkaloids possess various biological activities, such as anti-inflammatory, antiarrhythmic, cardiotonic, analgesic, antitumor, and acetylcholinesterase inhibition. In recent years, Wang Fengpeng et al. used an activity-tracking method to isolate C from Aconitum carmichaelii, which has cardiotonic and anti-heart failure effects. 19 - Diterpenoid alkaloids, such as zebuline. However, the cardiotonic effect of zebuline is still insufficient to meet the needs. Developing a new compound with superior cardiotonic effects is of great significance for the clinical prevention and treatment of heart failure. Summary of the Invention

[0006] The first object of the present invention is to provide C as shown in Formula I. 19 - Diterpenoid alkaloids and their preparation methods.

[0007] The second object of the present invention is to provide the above-mentioned C 19 - Use of diterpenoid alkaloids in the preparation of cardiotonic drugs, as well as drugs for the prevention and / or treatment of heart failure.

[0008] This invention provides compounds of Formula I or pharmaceutically acceptable salts thereof:

[0009]

[0010] Wherein, R1 is hydrogen, methyl or ethyl; R2 is hydroxyl, methoxy or ethoxy; R3 is hydroxyl or methoxy; and R4 is hydroxyl or methoxy.

[0011] Furthermore, the structure of the compound is selected from:

[0012]

[0013] The present invention also provides a method for preparing the above-mentioned compound, comprising the following steps:

[0014] a. Take plants of the genus Aconitum from the Ranunculaceae family, extract with ethanol, and concentrate the extract to obtain an extract;

[0015] b. Dissolve the extract in water, adjust the pH to 1-3, and extract with petroleum ether and ethyl acetate in sequence, and collect the aqueous phase.

[0016] c. Adjust the pH of the aqueous phase to 9.5–11.0, extract with dichloromethane, concentrate the dichloromethane extract, and obtain total alkaloids A;

[0017] d. Total alkaloids A were refluxed with a 5% NaOH methanol solution for 2 hours to adjust the pH to 8-9. The methanol was then recovered by concentration under reduced pressure to obtain total alkaloids B.

[0018] e. Total alkaloids B were obtained by normal-phase silica gel column chromatography with gradient elution using an eluent. The fractions were then analyzed by thin-layer chromatography and combined sequentially to obtain three parts: B-1, B-2, and B-3. The eluent was a mixed solution of CH2Cl2 and CH3OH in a ratio of 1:0 to 0:1.

[0019] f, B-1, B-2 and B-3 fractions were separated and purified by normal-phase silica gel column chromatography to obtain the target compound.

[0020] Furthermore, the ethanol mentioned in step a is 95% ethanol.

[0021] Furthermore, the plant of the genus Aconitum in the Ranunculaceae family mentioned in step a is Aconitum apetalum (Huth) B.Fedtsch.;

[0022] In step f:

[0023] When the B-1 part was purified by normal phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and the target compound obtained was compound 8;

[0024] When B-2 was purified by normal-phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1. The target compounds obtained were compound 1, compound 2, and compound 3.

[0025] When the B-3 part was purified by normal phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and the target compound obtained was compound 7.

[0026] Further, the plant of the genus Aconitum in the Ranunculaceae family mentioned in step a is *Aconitumbrevicalcaratum* (Finet & Gagnep.) Diels;

[0027] In step f:

[0028] When B-1 was purified by normal-phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and the target compounds obtained were compound 4, compound 5, and compound 6.

[0029] When the B-2 part was purified by normal phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and the target compounds obtained were compound 9 and compound 10.

[0030] The present invention also provides a pharmaceutical composition, which is a formulation prepared by using the above-mentioned compound or its pharmaceutically acceptable salt as the active ingredient and adding pharmaceutically acceptable excipients.

[0031] Furthermore, the preparation is an oral preparation.

[0032] The present invention also provides the use of the above-mentioned compounds or pharmaceutically acceptable salts thereof in the preparation of cardiotonic drugs.

[0033] The present invention also provides the use of the above-mentioned compounds or pharmaceutically acceptable salts thereof in the preparation of medicaments for the prevention and / or treatment of heart failure.

[0034] Definitions of terms used in this invention:

[0035] The term "pharmaceutically acceptable" means that a carrier, delivery substance, diluent, excipient, and / or the salt formed therefrom is generally chemically or physically compatible with other components constituting a drug dosage form and physiologically compatible with receptors.

[0036] The term "pharmaceutically acceptable salt" refers to acidic and / or basic salts formed by the above-mentioned compounds or their stereoisomers with inorganic and / or organic acids and bases, including zwitterionic salts (internal salts) and quaternary ammonium salts, such as alkylammonium salts. These salts can be obtained directly during the final separation and purification of the compounds. Alternatively, they can be obtained by mixing the above-mentioned compounds, or their stereoisomers, with an appropriate amount (e.g., equimolar amounts) of an acid or base. These salts may be obtained by precipitating in solution and collecting by filtration, or by recovery after solvent evaporation, or by freeze-drying after reaction in an aqueous medium. The salts described in this invention can be hydrochlorides, sulfates, citrates, benzenesulfonates, hydrobromides, hydrofluoric acids, phosphates, acetates, propionates, succinates, oxalates, malates, succinates, fumarates, maleates, tartrates, or trifluoroacetates of the compounds.

[0037] There are no particular limitations on the administration of the compounds or pharmaceutical compositions of the present invention. Representative administration methods include (but are not limited to): oral, parenteral (intravenous, intramuscular or subcutaneous), and topical administration.

[0038] Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In these solid dosage forms, the active compound is mixed with at least one conventional inert excipient (or carrier), such as sodium citrate or dicalcium phosphate, or with the following components: (a) fillers or compatibilizers, such as starch, lactose, sucrose, glucose, mannitol, and silica; (b) binders, such as hydroxymethyl cellulose, alginate, gelatin, polyvinylpyrrolidone, sucrose, and gum arabic; (c) humectants, such as glycerin; (d) disintegrants, such as agar, calcium carbonate, potato starch or cassava starch, alginate, certain complex silicates, and sodium carbonate; (e) slowing agents, such as paraffin; (f) absorption accelerators, such as quaternary ammonium compounds; (g) wetting agents, such as cetyl alcohol and glyceryl monostearate; (h) adsorbents, such as kaolin; and (i) lubricants, such as talc, calcium stearate, magnesium stearate, solid polyethylene glycol, sodium dodecyl sulfate, or mixtures thereof. Buffers may also be included in capsules, tablets, and pills.

[0039] Solid dosage forms such as tablets, sugar pills, capsules, pellets, and granules can be prepared using coatings and shells, such as casings and other materials known in the art. They may contain opacifying agents, and the release of the active compound or compound from such compositions can be delayed in a portion of the digestive tract. Examples of encapsulating components that can be used are polymeric substances and waxes. If necessary, the active compound may also be formed into microcapsules with one or more of the excipients described above.

[0040] Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups, or tinctures. In addition to the active compound, liquid dosage forms may contain inert diluents conventionally used in the art, such as water or other solvents, solubilizers and emulsifiers, e.g., ethanol, isopropanol, ethyl carbonate, ethyl acetate, propylene glycol, 1,3-butanediol, dimethylformamide, and oils, particularly cottonseed oil, peanut oil, corn germ oil, olive oil, castor oil, and sesame oil, or mixtures of these substances.

[0041] In addition to these inert diluents, the composition may also contain auxiliaries such as wetting agents, emulsifiers and suspending agents, sweeteners, flavoring agents and fragrances.

[0042] In addition to the active compound, the suspension may contain suspending agents such as ethoxylated isooctadecyl alcohol, polyoxyethylene sorbitol and dehydrated sorbitol esters, microcrystalline cellulose, aluminum methoxide and agar, or mixtures of these substances.

[0043] Compositions for parenteral injection may comprise physiologically acceptable sterile aqueous or anhydrous solutions, dispersions, suspensions, or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Suitable aqueous and non-aqueous carriers, diluents, solvents, or excipients include water, ethanol, polyols, and suitable mixtures thereof.

[0044] The pharmaceutically acceptable excipients described in this invention refer to substances other than the active ingredient contained in the dosage form.

[0045] The pharmaceutically acceptable adjuvant component described in this invention possesses certain physiological activities. However, the addition of this component does not alter the dominant role of the aforementioned pharmaceutical composition in the disease treatment process; rather, it merely exerts an adjuvant effect. These adjuvant effects are simply the utilization of the known activity of the component, and are a commonly used adjuvant therapy method in the pharmaceutical field. If the aforementioned adjuvant component is used in combination with the pharmaceutical composition of this invention, it should still fall within the scope of protection of this invention.

[0046] Pharmacological experiments showed that all compounds of the present invention have cardiotonic effects. In particular, the cardiotonic effects of compounds 1, 2, 4, 7, and 10 of the present invention were significantly enhanced compared with those of the positive control, urinine. The compounds of the present invention can be used to prepare cardiotonic drugs, as well as drugs for the prevention and / or treatment of heart failure.

[0047] The compounds of this invention can be extracted and isolated from plants of the Aconitum genus, and the drug source is wide-ranging, with broad clinical application prospects and market potential.

[0048] Obviously, based on the above description of the present invention, and according to common technical knowledge and conventional methods in the field, various other modifications, substitutions or alterations can be made without departing from the basic technical concept of the present invention.

[0049] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention. Detailed Implementation

[0050] The raw materials and equipment used in the specific embodiments of the present invention are all known products, obtained by purchasing commercially available products.

[0051] Example 1: Preparation of compounds 1-10 of the present invention

[0052] (a) Preparation of compounds 1, 2, 3, 7 and 8

[0053] Take 10 kg of tuberous roots of Aconitum apetalum (Huth) B.Fedtsch., a plant of the Ranunculaceae family. Soak the dried roots of Aconitum apetalum in 95% ethanol three times at room temperature, each time for 7 days. Combine the extracts and concentrate under reduced pressure to obtain an extract (510 g).

[0054] The extract was dissolved in water at 50°C, and the pH was first adjusted to 3.0 with 10% w / w hydrochloric acid solution, followed by extraction with petroleum ether and ethyl acetate. The aqueous phase was adjusted to pH 9.4 with 24% w / w concentrated ammonia solution, and then extracted with dichloromethane. The dichloromethane fraction was concentrated under reduced pressure to obtain total alkaloid A (90g).

[0055] Total alkaloids A were refluxed with a methanol solution of 5% NaOH for 2 hours to adjust the pH to 8-9. The methanol was then recovered by concentration under reduced pressure to obtain total alkaloids B.

[0056] Total alkaloids B were determined by normal-phase silica gel column chromatography with gradient elution using eluent (CH2Cl2:CH3OH = 1:0 to 0:1). The fractions were then analyzed by thin-layer chromatography and combined sequentially to obtain three fractions: B-1, B-2, and B-3.

[0057] Part B-1 was further separated and purified by repeated silica gel column chromatography. The mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, to obtain compound 8 (10 mg). Its structure was determined by nuclear magnetic resonance characterization.

[0058] Part B-2 was further separated and purified by repeated silica gel column chromatography. The mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, yielding compounds 1 (13 mg), 2 (17 mg), and 3 (11 mg), respectively. Their structures were determined by nuclear magnetic resonance characterization.

[0059] Part B-3 was further separated and purified by repeated silica gel column chromatography. The mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and compound 7 (22 mg) was obtained. Its structure was determined by nuclear magnetic resonance characterization.

[0060] (ii) Preparation of compounds 4, 5, 6, 9 and 10

[0061] Take 5 kg of tuberous roots of Aconitum brevicalcaratum (Finet & Gagnep.) Diels, a plant of the Ranunculaceae family. Under room temperature conditions, soak the dried roots of the hollow-stemmed Aconitum in 95% ethanol three times, each time for 7 days. Combine the extracts and concentrate under reduced pressure to obtain an extract (310 g).

[0062] The extract was dissolved in water at 50°C, and the pH was first adjusted to 3.0 with 10% w / w hydrochloric acid solution, followed by extraction with petroleum ether and ethyl acetate in sequence. The aqueous phase was adjusted to pH 9.4 with 24% w / w concentrated ammonia solution, and then extracted with dichloromethane. The dichloromethane fraction was concentrated under reduced pressure to obtain total alkaloid A (30g).

[0063] Total alkaloids A were refluxed with a methanol solution of 5% NaOH for 2 hours to adjust the pH to 8-9. The methanol was then recovered by concentration under reduced pressure to obtain total alkaloids B.

[0064] Total alkaloids B were determined by normal-phase silica gel column chromatography with gradient elution using eluent (CH2Cl2:CH3OH = 1:0 to 0:1). The fractions were then analyzed by thin-layer chromatography and combined sequentially to obtain three fractions: B-1, B-2, and B-3.

[0065] Part B-1 was further separated and purified by repeated silica gel column chromatography. The mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, and compounds 4 (5 mg), 5 (8 mg), and 6 (6 mg) were obtained. Their structures were determined by nuclear magnetic resonance characterization.

[0066] Part B-2 was further separated and purified by repeated silica gel column chromatography. The mobile phase was a mixed solution of CH2Cl2:MeOH:diethylamine = 100:1:0.1 to 10:1:0.1, yielding compounds 9 (15 mg) and 10 (18 mg), respectively. Their structures were determined by nuclear magnetic resonance characterization.

[0067] Compounds 1-10 of this invention are all C 19 Type diterpenoid alkaloids, their chemical structures and physicochemical constants are as follows:

[0068]

[0069] Compound 1: Carmaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400MHz) δ: 1.06 (3H, t, J=7.2Hz, NCH2CH3), 3.34, 3.27 (each 3H, s, 2×OCH3), 3.04 (1H, dd, J=10.8Hz, 6.6 Hz, H-1β), 4.14 (1H, t, J=4.8Hz, H-14β), 3.16 (1H, m, H-16α). 13C-NMR (CDCl3, 100MHz) δ: 86.4 (d, C-1), 25.8 (t, C-2), 32.2 (t, C-3), 39.2 (s, C-4), 46.0 (d, C-5), 24.7 (t, C-6), 45.9 (d, C-7), 73.0 (s, C-8), 47.0 (d, C-9), 45.6 (d, C-10), 48.9 (s, C-11), 27.8 (t, C-12), 37.6 (d, C-13), 75.7 (d, C-14), 38.4 (t, C-15), 82.3 (d, C-16), 63.2 (d, C-17), 69.0 (t, C-18), 53.1 (t, C-19), 49.6 (t, C-21), 13.8 (q, C-22), 56.7 (q, 1-OCH3), 56.5 (q, 16-OCH3).

[0070] Compound 2: N-deethyl-N-methylcammaconine, amorphous powder, showed a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400 MHz) δ: 3.10 (1H, m, H-1β), 4.14 (1H, t, J = 4.8Hz, H-14β), 3.43 (1H, m, H-16α), 3.25, 3.38 (each 1H, ABq, J=11.2Hz, H-18), 3.31, 3.37 (each 3H, s, 2×OCH3), 2.30 (3H, s, NCH3). 13 C-NMR (CDCl3, 100MHz) δ: 86.4 (d, C-1), 26.0 (t, C-2), 32.2 (t, C-3), 39.3 (s, C-4), 45.1 (d, C-5), 24.7(t, C-6), 45.0(d, C-7), 73.0(s, C-8), 47.1(d, C-9), 45.6(d, C-10), 48.9(s, C-11), 27.7(t, C-12), 37.6(d, C-13), 75.7(d, C-14), 38.4 (t, C-15), 82.3 (d, C-16), 64.0 (d, C-17), 69.0 (t, C-18), 55.8 (t, C-19), 42.7 (q, C-21), 56.6 (q, 1-OCH3), 56.7 (q, 16-OCH3).

[0071] Compound 3: N-deethyl cammaconine, amorphous powder, showed a positive reaction with potassium bismuth iodide.1 H-NMR (CDCl3, 400MHz) δ: 3.38 (1H, m, H-1β), 4.13 (1H, t, J=4.8Hz, H-14β), 3.33 (1H, m, H-16α), 3.17, 3.28 (each 1H, ABq, J=11.2Hz, H-18), 3.32, 3.35 (each 3H, s, 2×OCH3). 13 C-NMR (CDCl3, 100MHz) δ: 84.5 (d, C-1), 25.3 (t, C-2), 28.4 (t, C-3), 39.6 (s, C-4), 42.9 (d, C-5), 26.0 (t, C-6), 53.0 (d, C-7), 75.5 (s, C-8), 47.1 (d, C-9), 45.6 (d, C-10), 39.6 (s, C-11), 29.8 (t, C-12), 37.6 (d, C-13), 75.5 (d, C-14), 41.6 (t, C-15), 84.1 (d, C-16), 58.7 (d, C-17), 68.5 (t, C-18), 48.9 (t, C-19), 56.0 (q, 1-OCH3), 56.5 (q, 16-OCH3).

[0072] Compound 4: Scaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400MHz) δ: 3.04 (1H, dd, J=10.8Hz, 6.6Hz, H-1β), 3.62 (1H, t, J=4.8Hz, H-14β), 3.15 (1H, m, H-16α), 3.17, 3.28 (each 1H, ABq, J=11.2Hz, H-18), 0.99 (3H, t, J=7.2Hz, NCH2CH3), 3.32, 3.25, 3.21 (each 3H, s, 3×OCH3). 13C-NMR (CDCl3, 400MHz) δ: 85.7 (d, C-1), 26.3 (t, C-2), 32.2 (t, C-3), 38.8 (s, C-4), 45.6 (d, C-5), 24.9 (t, C-6), 45.4 (d, C-7), 74.2 (s, C-8), 46.3 (d, C-9), 45.7 (d, C-10), 48.7 (s, C-11), 29.4 (t, C-12), 36.8 (d, C-13), 84.4 (d, C-14), 41.6 (t, C-15), 82.6 (d, C-16), 62.4 (d, C-17), 68.7 (t, C-18), 52.9 (t, C-19), 49.3 (t, C-21), 13.5 (q, C-22), 56.2 (q, 1-OCH3), 57.6 (q, 14-OCH3), 56.2 (q, 16-OCH3).

[0073] Compound 5: 8-O-methyl cammaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400MHz) δ: 3.10 (1H, dd, J=10.8Hz, 6.6Hz, H-1β), 4.00 (1H, t, J=4.8Hz, H-14β), 3.29 (1H, m, H-16α), 3.28, 3.40 (each 1H, ABq, J=11.2Hz, H-18), 1.09 (3H, t, J=7.2Hz, NCH2CH3), 3.15, 3.29, 3.37 (each 3H, s, 3×OCH3). 13 C-NMR (CDCl3, 400MHz) δ: 85.8 (d, C-1), 25.8 (t, C-2), 31.9 (t, C-3), 38.0 (s, C-4), 46.0 (d, C-5), 23.5 (t, C-6), 40.1 (d, C-7), 77.9 (s, C-8), 45.6 (d, C-9), 45.6 (d, C-10), 48.9 (s, C-11), 28.4 (t, C-12), 38.9 (d, C-13), 75.1 (d, C-14), 33.2 (t, C-15), 82.3 (d, C-16), 62.9 (d, C-17), 68.9 (t, C-18), 53.0 (t, C-19), 49.4 (t, C-21), 13.5 (q, C-22), 56.4 (q, 1-OCH3), 48.3 (q, 8-OCH3), 56.4 (q, 16-OCH3).

[0074] Compound 6: 8,14-dimethoxycammaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400MHz) δ: 3.09 (1H, dd, J = 10.8Hz, 6.6Hz, H-1β), 3.55 (1H, t, J = 4.8Hz, H-14β), 3.25 (1H, m, H-16α), 3.22, 3.42 (each 1H, ABq, J = 11.2Hz, H-18), 1.07 (3H, t, J=7.2Hz, NCH2CH3), 3.13, 3.29, 3.36, 3.37 (each 3H, s, 4×OCH3). 13 C-NMR (CDCl3, 400MHz) δ: 85.8 (d, C-1), 26.5 (t, C-2), 32.1 (t, C-3), 38.8 (s, C-4), 45.8 (d, C-5), 23.9 (t, C-6), 40.1 (d, C-7), 77.6 (s, C-8), 43.7 (d, C-9), 45.3 (d, C-10), 49.2 (s, C-11), 29.5 (t, C-12), 38.1 (d, C-13), 83.7 (d, C-14), 35.5 (t, C-15), 83.8 (d, C-16), 61.8 (d, C-17), 69.2 (t, C-18), 53.0 (t, C-19), 49.3 (t, C-21), 13.6 (q, C-22), 56.3 (q, 1-OCH3), 48.1 (q, 8-OCH3), 57.7 (q, 14-OCH3), 56.3 (q, 16-OCH3).

[0075] Compound 7: 16-demethyl cammaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 400MHz) δ: 3.10 (1H, dd, J=10.8Hz, 6.6Hz, H-1β), 4.23 (1H, t, J=4.8Hz, H-14β), 3.82 (1H, m, H-16α), 3.19, 3.41 (each 1H, ABq, J = 11.2Hz, H-18), 1.07 (3H, t, J = 7.2Hz, NCH2CH3), 3.28 (3H, s, OCH3), 4.23 (1H, t, J = 4.8Hz, H-14β). 13C-NMR (CDCl3, 100MHz) δ: 86.4 (d, C-1), 25.6 (t, C-2), 32.0 (t, C-3), 39.1 (s, C-4), 45.8 (d, C-5), 24.5 (t, C-6), 46.4 (d, C-7), 73.8 (s, C-8), 46.4 (d, C-9), 45.2 (d, C-10), 48.8 (s, C-11), 27.9 (t, C-12), 40.6 (d, C-13), 75.6 (d, C-14), 42.1 (t, C-15), 72.4 (d, C-16), 63.3 (d, C-17), 68.4 (t, C-18), 53.1 (t, C-19), 49.6 (t, C-21), 13.6 (q, C-22), 56.4 (q, 1-OCH3).

[0076] Compound 8: 8-Ethoxycarmaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1 H-NMR (CDCl3, 600MHz) δ: 1.05 (3H, t, J=7.2Hz, OCH2CH3), 1.11 (3H, t, J=7.2Hz, NCH2CH3), 3.35, 3.26 (each 3H, s, 2×OCH3). 13 C-NMR (CDCl3, 150MHz) δ: 86.0 (d, C-1), 26.2 (t, C-2), 32.2 (t, C-3), 38.6 (s, C-4), 45.9 (d, C-5), 23.8 (t, C-6), 40.8 (d, C-7), 78.2 (s, C-8), 45.6 (d, C-9), 45.8 (d, C-10), 48.9 (s, C-11), 28.9 (t, C-12), 39.0 (d, C-13), 75.3 (d, C-14), 34.7 (t, C-15), 82.6 (d, C-16), 62.9 (d, C-17), 69.1 (t, C-18), 52.9 (t, C-19), 49.5 (t, C-21), 13.7 (q, C-22), 56.5 (q, 1-OCH3), 56.5 (q, 16-OCH3), 56.0 (t, 8-OCH2CH3), 16.3 (q, 8-OCH2CH3).

[0077] Compound 9: 8-Ethoxy,14-Methoxycarbaconine, a white amorphous powder, shows a positive result in the potassium bismuth iodide reaction. 1H-NMR (CDCl3, 600MHz) δ: 1.05 (3H, t, J=6.0Hz, NCH2CH3), 3.27, 3.34, 3.36 (each 3H, s, 3×OCH3). 13 C-NMR (CDCl3, 150MHz) δ: 86.0 (d, C-1), 26.7 (t, C-2), 32.2 (t, C-3), 38.9 (s, C-4), 45.3 (d, C-5), 24.1 (t, C-6), 41.1 (d, C-7), 77.5 (s, C-8), 43.1 (d, C-9), 46.0 (d, C-10), 49.3 (s, C-11), 29.6 (t, C-12), 39.2 (d, C-13), 84.0 (d, C-14), 36.3 (t, C-15), 84.1 (d, C-16), 61.9 (d, C-17), 69.4 (t, C-18), 53.1 (t, C-19), 49.4 (t, C-21), 13.7 (q, C-22), 56.5 (q, 1-OCH3), 57.8 (q, 14-OCH3), 56.5 (q, 16-OCH3), 55.5 (t, -OCH2CH3), 16.3 (q, OCH2CH3).

[0078] Compound 10: N-deethyl-N-methyl-14-methoxy-carmaconine, amorphous powder, positive for potassium bismuth iodide reaction. HR–ESI–MS m / z: 408.2735 [M+H] + (calcd.for C 23 H 38 NO5, 408.2750); 1 H-NMR (CDCl3, 400MHz) δ: 3.12 (1H, m, H-1β), 4.17 (1H, t, J = 4.8 Hz, H-14β), 3.38 (1H, m, H-16α), 3.25, 3.31, 3.37 (each 3H, s, 3×OCH3), 2.30(3H,s,NCH3).

[0079] The following pharmacological experiments demonstrate the beneficial effects of this invention.

[0080] Experimental Example 1: Cardiotonic effect of the compound on isolated bullfrog heart in vitro

[0081] 1. Experimental Methods

[0082] The in vitro preparation of isolated bullfrog hearts was carried out according to the method described in the literature (Ding Hong, ed., Experimental Pharmacology, pp. 504-506, Science Press, 2008), specifically as follows: Bullfrogs weighing 150-200 grams, regardless of sex, were used. At room temperature, the bullfrog's brain and spinal cord were destroyed with a metal probe, the chest wall was cut open to expose the heart, and a suture was threaded under each of the left and right aortas. After directly tying a knot in the right aorta, a "V"-shaped incision was made in the left aorta with scissors. A frog heart cannula containing a small amount of Ringer's solution was inserted into the ventricle. The suture under the left aorta was connected and fixed to the side hook of the cannula. The blood in the bullfrog heart tube was repeatedly flushed with fresh Ringer's solution until the liquid was clear and colorless. The heart cannula was inserted into the ventricle and Ringer's solution was infused. The frog heart cannula was fixed to an iron stand with clamps, and a muscle tone transducer was fixed below the frog heart cannula. The isolated frog heart was connected to the tension transducer via frog heart clamps and sutures. Adjust the solution volume in the cannula to 1.0 mL, and add the test compound or an equal volume of solvent to the cannula. Evaluate the cardiac activity of the test compound on an isolated perfused frog heart, and record the heart rate and contraction amplitude.

[0083] The cardiotonic effects of compounds 1-10 of this invention on isolated bullfrog hearts were investigated. Deacetylated hymenoside and gentianin were used as positive controls.

[0084] The test concentration of compounds 1-10 was 0.005 mol / mL; the test concentration of the positive control drug guanine was 0.01 mol / mL; and the test concentration of the positive control drug deacetylated guanine was 0.0002 mol / mL.

[0085] 2. Experimental Results

[0086] Table 1. Results of cardiotonic experiments on isolated bullfrog hearts using the compounds.

[0087] compound Average increase rate (%) result 1 117.6 powerful 2 159.3 powerful 3 36.8 Significant 4 155.9 powerful 5 33.6 Significant 6 31.2 Significant 7 75.2 powerful 8 57.2 Significant 9 21.8 medium 10 148.1 powerful Deacetylated glycoside 61 powerful Zhongwu Ningjian 70.7 powerful

[0088] Note: In Table 1, the average increase rate (%) represents the average amplitude growth rate (%) of the frog heart. Based on the magnitude of the value, the cardiotonic effect is divided into the following 4 categories: 0-15% (none); 16%-30% (+, moderate); 31%-60% (++, significant); >60% (+++, strong).

[0089] The above experimental results show that compounds 1-10 of the present invention all have cardiotonic effects. In particular, compared with the positive control urinine, compounds 1, 2, 4, 7, and 10 of the present invention exhibited better cardiotonic effects at lower test concentrations, indicating that the cardiotonic effects of compounds 1, 2, 4, 7, and 10 of the present invention are significantly enhanced. The compounds of the present invention can be used to prepare cardiotonic drugs, as well as drugs for the prevention and / or treatment of heart failure.

[0090] In summary, the present invention provides a C as shown in Formula I.19 Diterpenoid alkaloids, their preparation methods, and uses. Pharmacological experiments show that the compounds of this invention all have cardiotonic effects and can be used to prepare cardiotonic drugs, as well as drugs for the prevention and / or treatment of heart failure. The compounds of this invention can be extracted and isolated from plants of the genus Aconitum, making them widely available and possessing broad clinical application and market prospects.

Claims

1. A compound or a pharmaceutically acceptable salt thereof, characterized in that: The structure of the compound is selected from: 。 2. A method for preparing the compound of claim 1, characterized in that: Includes the following steps: a. Take plants of the genus Aconitum from the Ranunculaceae family, extract with 95% ethanol, and concentrate the extract to obtain an extract; b. Dissolve the extract in water, adjust the pH to 1-3, and extract with petroleum ether and ethyl acetate in sequence, and collect the aqueous phase. c. Adjust the pH of the aqueous phase to 9.5-11.0, extract with dichloromethane, concentrate the dichloromethane extract, and obtain total alkaloids A; d. Total alkaloids A were refluxed with a 5% NaOH methanol solution for 2 hours to adjust the pH to 8-9. The methanol was then recovered by concentration under reduced pressure to obtain total alkaloids B. e. Total alkaloids B were obtained by normal-phase silica gel column chromatography with gradient elution using an eluent. The fractions were then analyzed by thin-layer chromatography and combined sequentially to obtain three fractions: B-1, B-2, and B-3. The eluent was a mixed solution of CH2Cl2 and CH3OH in a ratio of 1:0 to 0:

1. f, B-1, B-2 and B-3 fractions were separated and purified by normal phase silica gel column chromatography to obtain the target compound; The plant of the genus Aconitum in the Ranunculaceae family mentioned in step a is hollow-stemmed Aconitum. Aconitum apetalum (Huth) B.Fedtsch.; In step f: When B-2 was purified by normal-phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2: MeOH: diethylamine = 100:1:0.1~10:1:0.1, and the target compound obtained was compound 2. Alternatively, the aconite plant in step a (Ranunculaceae family) is *Aconitum short-spurred*. Aconitum brevicalcaratum (Finet & Gagnep.) Diels; In step f: When the B-2 part was purified by normal phase silica gel column chromatography, the mobile phase was a mixed solution of CH2Cl2: MeOH: diethylamine = 100:1:0.1~10:1:0.1, and the target compound obtained was compound 10.

3. A pharmaceutical composition, characterized in that: It is a formulation prepared by using the compound of claim 1 or its pharmaceutically acceptable salt as the active ingredient, plus pharmaceutically acceptable excipients or pharmaceutically acceptable auxiliary ingredients.

4. The pharmaceutical composition according to claim 3, characterized in that: The preparation is an oral preparation.

5. , Use of the compound of claim 1 or a pharmaceutically acceptable salt thereof in the preparation of a cardiotonic drug.

6. , Use of the compound of claim 1 or a pharmaceutically acceptable salt thereof in the preparation of a medicament for the prevention and / or treatment of heart failure.

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