Triprostine prodrugs and their applications

Abstract

This invention provides a prodrug of treprostrin as shown in Formula I and a pharmaceutical composition thereof. The prodrug can specifically bind to prostaglandin receptors, relax vascular smooth muscle, and can be used to treat diseases such as pulmonary hypertension, chronic arterial occlusive disease, and idiopathic pulmonary fibrosis. The prodrug also optimizes the pharmacokinetic characteristics and irritant properties of treprostrin, reduces the dosage and frequency of administration, and improves the efficacy and safety of the drug.

Description

Technical Field

[0001] This invention belongs to the field of biomedicine, specifically relating to the prodrug of treprostrin, its pharmaceutical composition and uses. Background Technology

[0002] Pulmonary hypertension (including pulmonary arterial hypertension, PAH) is a group of diseases characterized by increased pulmonary vascular resistance and right ventricular failure. Patients diagnosed with PAH have a short survival rate and high mortality rate, making it a malignant disease. Prostacyclin in the body activates adenylate cyclase by interacting with prostacyclin receptors on platelets or vascular smooth muscle, thereby increasing intracellular cAMP concentration and thus dilating blood vessels. Prostacyclin can antagonize thromboxane A2 (TXA2). In PAH patients, prostacyclin synthesis is reduced, and TXA2 concentration is increased, leading to vasoconstriction, endothelial cell proliferation, and platelet activation (Tuder RM et al., Am Jrespir Crit Care Med, 1999).

[0003] Treprostinil, a prostaglandin analogue, specifically binds to prostaglandin receptors, exerting effects such as relaxing vascular smooth muscle, reducing pulmonary artery pressure, and inhibiting pulmonary vascular remodeling and in situ thrombosis. This drug produces effects similar to prostacyclin (PGI2), including pulmonary and circulatory vasodilation, inhibition of platelet aggregation, and inhibition of smooth muscle cell proliferation (Clapp LH et al., Am J Respir Cell Mol Biol, 2002). Currently, it is also believed that the vasodilatory and anti-proliferative effects of treprostinil are mediated by peroxisome proliferator-activated receptors (PPR) (Li Y et al., Am J Respir Cell Mol Biol, 2012). The injectable formulation of this drug, developed by United Therapeutics, was approved by the FDA in 2002 for the treatment of pulmonary arterial hypertension (PAH) in the United States. In April 2021, it was further approved for the treatment of interstitial lung disease-associated pulmonary arterial hypertension (PH-ILD). Compared to the shorter half-lives of enoprostol and enoxaprostol, treprostol has a significant advantage with an elimination half-life of approximately 4 hours. The main route of excretion is urine (79%). Elimination is reduced by 80% in patients with hepatic impairment, while oral exposure is not increased in patients with renal impairment. Dialysis can reduce the exposure of this drug by 50% (Jenkins A, et al., Am Jrespir Crit Care Med, 2011).

[0004] Treprostrin is currently the only prostacyclin-like drug available clinically for the treatment of PAH that can be administered via subcutaneous / intravenous, oral, and inhalation routes. It has a stable structure, a longer duration of action than prostacyclin, and rapid onset of action via subcutaneous / intravenous administration, reaching its biological effect within minutes. In clinical studies of PAH, subcutaneous, intravenous, and inhalation administration have all demonstrated good efficacy and safety. The subcutaneous and intravenous formulations (treprostrin for injection, brand name: Remodulin), the inhalation solution (brand name: Tyvaso), the extended-release tablets (brand name: Orenitram), and the injection solution (brand name: Remodulin) were approved by the FDA in 2002, 2009, 2013, and 2018, respectively.

[0005] Because long-term administration is required, injection and inhalation are very inconvenient, making oral administration the optimal route. However, oral formulations are not very effective, have systemic toxic side effects, and require multiple daily doses. Therefore, sustained-release tablets have been developed and marketed for clinical use. However, due to inherent defects in the compound itself, the clinical use of oral formulations has been limited, with inhaled formulations being the primary option. For example, the latest international multicenter clinical trial summary report on inhaled treprostinil for the treatment of pulmonary hypertension was published in the New England Journal of Medicine in 2021. To improve patient compliance and reduce the toxic side effects of systemic administration, INSMED modified treprostinil to palmitic acid (treprostinil palmitil) as a long-acting-release prodrug inhaler (patents US09255064 and US09469600) for the treatment of pulmonary arterial hypertension, interstitial lung disease-associated pulmonary hypertension, and idiopathic fibrosis. This project has now entered Phase II clinical trials.

[0006] Therefore, exploring suitable prodrugs or dosage forms to further improve the in vivo metabolic characteristics of treprostinil, reduce the dosage and frequency of administration, and reduce the toxic side effects caused by direct exposure has positive clinical value. Summary of the Invention

[0007] This invention addresses the problems existing in the prior art by providing a prodrug of treprostrin, which optimizes the pharmacokinetic characteristics of treprostrin, reduces the dosage and frequency of administration, and improves the efficacy and safety of the drug.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] On one hand, the present invention provides a prodrug of treprostrin or a pharmaceutically acceptable salt or stereoisomer thereof, the structure of which is shown in Formula I below:

[0011] in,

[0012] R1 is hydrogen, alkyl, cycloalkyl, alkoxy, or aryl;

[0013] R2 is an alkyl, cycloalkyl, alkoxy, alkylamine, or hydroxyl group;

[0014] n is an integer between 0 and 6.

[0015] On the other hand, the present invention provides a pharmaceutical composition comprising the above-mentioned prodrug of treprostrin or a pharmaceutically acceptable salt thereof.

[0016] In another aspect, the present invention provides the use of the above-mentioned prodrug of treprostrin or a pharmaceutically acceptable salt thereof or the above-mentioned pharmaceutical composition as a procyclosporine analogue.

[0017] In another aspect, the present invention provides the use of the above-mentioned prodrug of treprostinil or a pharmaceutically acceptable salt thereof or the above-mentioned pharmaceutical composition in the preparation of a medicament for treating pulmonary hypertension, chronic arterial occlusive disease, idiopathic pulmonary fibrosis, etc.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention provides a series of prodrugs of treprostine that can specifically bind to prostaglandin receptors, relax vascular smooth muscle, and can be used to treat diseases such as pulmonary hypertension, chronic arterial occlusive disease, and idiopathic pulmonary fibrosis.

[0020] The prodrug of treprostrin provided by this invention optimizes the pharmacokinetic characteristics and irritant properties of treprostrin, reduces the dosage and frequency of administration, and improves the efficacy and safety of the drug. Attached Figure Description

[0021] Figure 1 The results of the in vivo experiment on rats with hypoxic pulmonary hypertension, Example 2. Detailed Implementation

[0022] The present invention will now be described in detail.

[0023] On one hand, the present invention provides a prodrug of treprostine as shown in Formula I:

[0025] Or its pharmaceutically acceptable salts or stereoisomers;

[0026] in,

[0027] R1 is hydrogen, alkyl, cycloalkyl, alkoxy, or aryl;

[0028] R2 is an alkyl, cycloalkyl, alkoxy, alkylamine, or hydroxyl group;

[0029] n is an integer from 0 to 6, for example, n can be 0, 1, 2, 3, 4, 5 or 6.

[0030] In some embodiments of the present invention, R1 is hydrogen or C. 1-20 Alkyl, C 3-20 cycloalkyl, C 1-20 Alkoxy or C 7-20 Aryl; R2 is C 1-20 Alkyl, C 3-20 cycloalkyl, C 1-20 Alkoxy, C 1-20 Alkylamine or hydroxyl groups.

[0031] In some embodiments of the present invention, R1 is hydrogen or C. 1-10 Alkyl; R2 is C 1-10 Alkyl, C 3-7 cycloalkyl, C 1-6 alkylamine, hydroxyl or C 1-6 Alkyl group.

[0032] In some embodiments of the present invention, R1 is hydrogen, methyl, or isopropyl; R2 is methyl, ethyl, n-propyl, isopropyl, tert-butyl, cyclopropyl, cyclohexyl, hydroxyl, methoxy, ethoxy, propoxy, methylamino, ethylamino, butylamino, 2-methylpropyl-1-amine, n-hexyl, n-heptyl, or n-octyl; and n is 0, 1, 2, or 3.

[0033] In some embodiments of the present invention, the prodrug of treprostyl is selected from any of the following structures:

[0036] On the other hand, the present invention provides a pharmaceutical composition comprising the above-mentioned prodrug of treprostrin or a pharmaceutically acceptable salt or stereoisomer thereof.

[0037] In some embodiments of the invention, the pharmaceutical composition further comprises pharmaceutically acceptable excipients.

[0038] The pharmaceutical excipients described herein may be those widely used in the pharmaceutical manufacturing field. Excipients primarily serve to provide a safe, stable, and functional pharmaceutical composition, and may also provide methods for enabling the active ingredient to dissolve at a desired rate after administration to a subject, or to promote the effective absorption of the active ingredient after administration to a subject. The pharmaceutical excipients may be inert fillers, or provide a function such as stabilizing the overall pH of the composition or preventing the degradation of the active ingredient. The pharmaceutical excipients may include one or more of the following: binders, suspending agents, emulsifiers, diluents, fillers, granulating agents, adhesives, disintegrants, lubricants, anti-adhesion agents, flow aids, wetting agents, gelling agents, absorption delay agents, dissolution inhibitors, enhancers, adsorbents, buffers, chelating agents, preservatives, colorants, flavoring agents, and sweeteners.

[0039] In some embodiments of the invention, the pharmaceutical composition is typically formulated into a dosage form suitable for oral, injectable, or inhaled administration to a patient.

[0040] In some embodiments of the present invention, the dosage form is an oral dosage form, such as tablets, capsules, sac-like tablets, pills, tablets containing tablets, powders, syrups, elixirs, suspensions, solutions, emulsions, granules, and capsules, etc.

[0041] The pharmaceutical compositions of the present invention can be prepared using any method known to those skilled in the art, based on the disclosure. For example, conventional mixing, dissolving, granulation, emulsification, grinding, encapsulation, embedding, or lyophilization processes.

[0042] In another aspect, the present invention provides the use of the above-mentioned prodrug of treprostrin or its pharmaceutically acceptable salt, stereoisomer, or the above-mentioned pharmaceutical composition as a procyclosporine analog.

[0043] In another aspect, the present invention provides the use of the above-mentioned prodrug of treprostinil or its pharmaceutically acceptable salt, stereoisomer or the above-mentioned pharmaceutical composition in the preparation of medicaments for treating cardiovascular diseases, cerebrovascular diseases, respiratory diseases, etc., especially in medicaments for pulmonary hypertension, chronic arterial occlusive disease, idiopathic pulmonary fibrosis, etc.

[0044] Definitions and general terms

[0045] The term "pharmaceutically acceptable salt" refers to both organic and inorganic salts of the compounds of this invention. Pharmaceutically acceptable salts are well-known in the field, as described in Berge et al., "describe pharmaceutically acceptable salts in detail" in J. Pharmacol Sci., 1977, 66, 1-19. Salts formed from pharmaceutically acceptable non-toxic acids include, but are not limited to, inorganic acid salts formed by reactions with amino groups, such as hydrochlorides, hydrobromic acids, phosphates, sulfates, perchlorates, etc.; and organic acid salts, such as acetates, oxalates, maleates, tartrates, citrates, succinates, malonates, etc., or obtained by other methods described in the literature, such as ion exchange. Other pharmaceutically acceptable salts include adipate, alginate, ascorbate, aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, cyclopentylpropionate, digluconate, dodecyl sulfate, ethanesulfonate, formate, transbutenedioic acid, glucono-p-gluconate, glycerophosphate, gluconate, hemisulfate, heptaate, hexanoate, hydroiodate, 2-hydroxy-ethanesulfonate, lacturonate, lactate, laurate, lauryl sulfate, malate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, palmitate, pyruvate, pectinate, persulfate, 3-phenylpropionate, picrate, pentanoate, propionate, stearate, thiocyanate, p-toluenesulfonate, undecanoate, valerate, etc. Salts obtained by applying appropriate bases include alkali metals, alkaline earth metals, and ammonium salts. Alkali metal or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, etc. Pharmaceutically acceptable salts further include suitable, non-toxic ammonium, quaternary ammonium salts, and amine cations that resist the formation of equilibrium ions, such as halides, hydroxides, carboxylates, sulfates, phosphates, nitrates, C1-8 sulfonates, and aromatic sulfonates.

[0046] The term "stereoisomer" refers to compounds with the same chemical structure but different spatial arrangements of atoms or groups. Stereoisomers include enantiomers, diastereomers, conformational isomers (rotational isomers), geometric isomers, (cis / trans) isomers, and trans-reactive isomers, etc. An enantiomer is a non-overlapping, mirror-image isomer of a compound. A diastereomer is a stereoisomer with two or more chiral centers whose molecules are not mirror images of each other. Diastereomers possess different physical properties, such as melting point, boiling point, spectral properties, and reactivity. Mixtures of diastereomers can be separated using high-resolution analytical techniques such as electrophoresis and chromatography, for example, HPLC.

[0047] The term "alkyl" or "alkyl group" refers to a saturated straight-chain or branched monovalent hydrocarbon group containing 1 to 20 carbon atoms. The alkyl group may be independently and optionally substituted by one or more substituents. Examples of alkyl or alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butylisobutyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl, 3-pentyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 3-methyl-1-butyl, 2-methyl-1-butyl, n-hexyl, 2-hexyl, 3-hexyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 3-methyl-3-pentyl, 2-methyl-3-pentyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, n-heptyl, n-octyl, etc.

[0048] The term "alkoxy" indicates that an alkyl group is attached to the rest of the molecule via an oxygen atom, wherein the alkyl group has the meaning as described in this invention. Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, 1-propoxy, 2-propoxy, 1-butoxy, 2-methyl-1-propoxy, 2-butoxy, 2-methyl-2-propoxy, 1-pentoxy, 2-pentoxy, 3-pentoxy, 2-methyl-2-butoxy, 3-methyl-2-butoxy, 3-methyl-1-butoxy, 2-methyl-1-butoxy, etc.

[0049] The term "aryl" refers to a monocyclic, bicyclic, or tricyclic carbocyclic system containing 6-20 membered rings, wherein at least one ring system is aromatic, and each ring system contains 3-7 membered rings with only one attachment point connected to the rest of the molecule. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, and anthracene, etc.

[0050] The term "cycloalkyl" refers to a C3-C20 aliphatic ring structure; examples of cycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and similar groups.

[0051] The term "alkylamine" indicates the group -NHR or -NRR, where R represents an alkyl or cycloalkyl group as described above.

[0052] The term "hydroxyl group" represents -OH.

[0053] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, it is worth noting that the raw materials involved in the present invention are all commercially available products unless otherwise specified.

[0054] Example 1

[0056] Synthesis route:

[0058] Synthesis of Compound 1

[0059] O-TES-protected treprostrin (20 mg), potassium iodide (25 mg), and potassium carbonate (21 mg) were dissolved in 10 mL of acetonitrile. After stirring at room temperature for 10 min, methyl chloroacetate (15 mg) was slowly added, and the mixture was reacted at 80 °C for 8 h. The reaction was stopped, the solvent was evaporated, dichloromethane was added, and the mixture was washed twice with water and once with saturated brine. The organic phase was concentrated, purified by column chromatography, concentrated, dissolved in THF / water, and 2N HCl was added. The reaction was stirred at room temperature, and TLC was used to detect complete reaction. The solvent was evaporated, and the mixture was purified by HPLC to obtain Example 1, with a yield of 42%. 1 HNMR(300MHz,DMSO-d)δ7.13(t,J=7.5Hz,1H),7.02–6.96(m,1H),6.88(dd,J=7.3,2.0Hz,1H),5.35– 5.12(m,2H),4.75(s,2H),3.70(d,J=7.7Hz,2H),3.06(d,J=12.8Hz,2H),2.90–2.63(m,2H),2.60–2. 37(m,2H),2.12(s,3H),2.09–1.96(m,2H),1.78–1.67(m,2H),1.61(dd,J=12.4,1.9Hz,2H),1.59–1. 39(m,4H),1.39–1.27(m,4H),1.11(d,J=12.5Hz,1H),0.86(t,J=5.3Hz,3H).ESI-MSm / z:463.6[M+H] + .

[0060] Example 2

[0062] Compound 2 can be prepared by replacing methyl chloroacetate with methyl chloropropionate using the synthesis method described in Example 1. 1 H NMR(300MHz,DMSO-d)δ7.11(t,J=7.5Hz,1H),7.00–6.85(m,2H),5.45–5.27(m,2H),4.75(s,2H),3.73(d,J=7.9H z,2H),3.01(d,J=11.8Hz,2H),2.87–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.35(s,2H),2.08–1.92(m,3H),1.77–

[0063] 1.58(m,4H),1.58–1.37(m,4H),1.37–1.27(m,4H),1.17–1.03(m,4H),0.90(t,J=5.2Hz,3H).ESI-MS m / z:477.3[M+H] + .

[0064] Example 3

[0066] Compound 3 can be prepared by replacing methyl chloroacetate with ethyl 1-chloroacetate using the synthesis method described in Example 1. 1 H NMR(300MHz,DMSO-d)δ7.22(t,J=7.2Hz,1H),6.97(dd,J=7.5,2.0Hz,2H),5.82–5.77(m,1 H),4.68(d,J=1.8Hz,2H),3.77(d,J=4.9Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz ,1H),2.85–2.65(m,2H),2.56(d,J=13.0Hz,2H),2.14–1.93(m,5H),1.79–1.59(m,7H),1. 59–1.37(m,4H),1.37–1.26(m,4H),1.11(d,J=12.5Hz,1H),0.91(t,J=5.3Hz,3H).ESI-MS m / z:477.3[M+H] + .

[0067] Example 4

[0069] Compound 4 can be prepared by replacing methyl chloroacetate with ethyl 1-chloropropionate using the synthesis method described in Example 1. 1H NMR(300MHz,DMSO-d)δ7.07(t,J=7.7Hz,1H),6.99–6.89(m,2H),5.84–5.79(m,1H),4. 04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.85–2.62(m,2H), 2.56(d,J=13.0Hz,1H),2.38(d,J=27.7Hz,3H),2.05–1.93(m,4H),1.80–1.57(m,7H), 1.56–1.39(m,4H),1.39–1.26(m,4H),1.23–1.03(m,4H),0.91(t,J=5.3Hz,3H).ESI-MS m / z:513.3[M+Na] + .

[0070] Example 5

[0072] Compound 5 can be prepared by replacing chloromethyl acetate with chloromethyl isobutyrate using the synthesis method described in Example 1. 1 HNMR(300MHz,DMSO-d)δ7.14(t,J=7.2Hz,1H),6.97–6.85(m,2H),4.92–4.61(m,4H),4.18(d,J=5.1Hz,1H),3 .77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.85–2.66(m,2H),2.63–2.47(m,2H),2.08–1.90(m,4H),1.81–

[0073] 1.58(m,4H),1.58–1.38(m,4H),1.38–1.27(m,4H),1.22–1.08(m,7H),0.86(t,J=5.2Hz,3H).ESI-MS m / z:491.3[M+H] + .

[0074] Example 6

[0076] Compound 6 can be prepared by replacing chloromethyl acetate with chloromethyl neopentanoate using the synthesis method described in Example 1. 1H NMR(300MHz,DMSO-d)δ7.15(t,J=7.2Hz,1H),7.01(t,J=7.5Hz,1H),6.89(dd,J=7.3,2.0Hz,1H),5.25– 5.04(m,2H),4.86–4.73(m,2H),4.04(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2. 84–2.66(m,2H),2.56(d,J=13.0Hz,1H),2.07–1.93(m,2H),1.86–1.67(m,4H),1.61(dd,J=12.4,1.9Hz ,2H),1.58–1.37(m,4H),1.31(dd,J=3.8,0.8Hz,4H),1.13–1.07(m,10H),0.89(t,J=5.5Hz,3H).ESI-MS m / z:505.3[M+H] + .

[0077] Example 7

[0079] Compound 7 can be prepared by replacing methyl chloroacetate with methyl chlorobutyrate using the synthesis method described in Example 1. 1 H NMR(300MHz,DMSO-d)δ7.17(t,J=7.2Hz,1H),7.02–6.91(m,2H),5.29–5.02(m,2H),4.75–4.66(m,2 H),4.18(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.86–2.68(m,2H),2.56(d ,J=13.0Hz,1H),2.46–2.28(m,3H),2.08–1.92(m,4H),1.78–1.59(m,6H),1.58–1.48(m,2H),1.48– 1.38(m,2H),1.38–1.25(m,4H),1.11(d,J=12.5Hz,1H),1.04–0.84(m,6H).ESI-MSm / z:513.3[M+Na] + .

[0080] Example 8

[0082] Compound 8 can be prepared by replacing methyl chloroacetate with ethyl 1-chlorobutyrate using the synthesis method described in Example 1. 1H NMR(300MHz, DMSO-d)δ7.15(t,J=7.3Hz,1H),7.01–6.91(m,2H),5.81–5.74(m,1H),4.79–4. 59(m,2H),4.15(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.88–2.63( m,2H),2.56(d,J=13.0Hz,1H),2.36–2.20(m,3H),2.08–1.94(m,4H),1.82–1.57(m,9H),1.5 7–1.39(m,4H),1.31(dd,J=3.8,0.8Hz,4H),1.14(d,J=9.5Hz,1H),1.01–0.84(m,6H).ESI-MS m / z:503.3[M+H] + .

[0083] Example 9

[0085] Compound 9 can be prepared by replacing chloromethyl acetate with 1-chloroethyl isobutyrate using the synthesis method described in Example 1. 1 H NMR(300MHz,DMSO-d)δ7.13(t,J=7.2Hz,1H),7.03–6.92(m,2H),5.83–5.74(m,1H),4. 79–4.60(m,2H),4.19(d,J=5.2Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H), 2.84–2.67(m,2H),2.61–2.46(m,2H),2.12–1.94(m,4H),1.82–1.57(m,7H),1.57–1.3 7(m,4H),1.31(dd,J=3.8,0.8Hz,4H),1.25–1.06(m,7H),0.89(t,J=5.3Hz,3H).ESI-MS m / z:505.3[M+H] + .

[0086] Example 10

[0088] Compound 10 can be prepared by replacing chloromethyl acetate with 1-chloroethyl neopentanoate using the synthesis method described in Example 1. 1HNMR(300MHz,DMSO-d)δ7.15(t,J=7.0Hz,1H),7.03–6.85(m,2H),5.86–5.74(m,1H),4. 78–4.54(m,2H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2. 85–2.66(m,2H),2.56(d,J=13.0Hz,1H),2.05–1.93(m,4H),1.82–1.57(m,7H),1.57–1.3 6(m,4H),1.31(dd,J=3.8,0.8Hz,4H),1.13–1.03(m,10H),0.89(t,J=5.3Hz,3H).ESI-MS m / z:541.3[M+

[0089] Na] + .

[0090] Example 11

[0092] Compound 11 can be prepared by replacing chloromethyl acetate with 1-chloroethylcyclohexane carboxylate using the synthesis method described in Example 1. 1 HNMR(300MHz,DMSO-d)δ7.08(dd,J=7.8,7.2Hz,1H),7.02–6.84(m,2H),5.77–5.64(m,1H),4.80 –4.56(m,2H),4.15(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.83–2.65( m,2H),2.56(d,J=13.0Hz,1H),2.39(d,J=17.9Hz,2H),2.07(d,J=13.0Hz,2H),2.01–1.87(m,4H ),1.84–1.67(m,7H),1.67–1.26(m,16H),1.11(d,J=12.5Hz,1H),0.92(t,J=5.3Hz,3H).ESI-MS m / z:545.4[M+H] + .

[0093] Example 12

[0095] Compound 12 can be prepared by replacing methyl chloroacetate with 1-chloro-2-methylpropyl isobutyrate using the synthesis method described in Example 1. 1H NMR(300MHz,DMSO-d)δ7.15(t,J=7.5Hz,1H),7.04–6.86(m,2H),5.65–5.47(m,1H),4.68(d ,J=1.8Hz,2H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.84– 2.66(m,2H),2.65–2.47(m,2H),2.19(d,J=29.5Hz,2H),2.09–1.90(m,4H),1.84–1.67(m,2 H),1.67–1.38(m,6H),1.36–1.19(m,10H),1.19–0.99(m,7H),0.94(t,J=5.3Hz,3H).ESI-MS m / z:533.3[M+H] + .

[0096] Example 13

[0098] Synthetic route

[0100] Synthesis of Compound 13

[0101] Methylamine (2 mmol) was dissolved in dichloromethane. At 0°C, N,N,N',N'-tetramethyl-1,8-naphthyldiamine (2.2 mmol) was added, and the mixture was stirred for 2 min. Then, methyl chloroformate (2.2 mmol) was added dropwise, and the reaction was allowed to proceed overnight at room temperature. The reaction was confirmed to be complete by TLC. The mixture was washed twice with water and once with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated to dryness. The prepared compound (0.2 mmol), along with O-TES-protected treprostyl (0.1 mmol) and DIPEA (0.2 mmol), were dissolved in dichloromethane. After stirring at room temperature for two hours, the reaction was confirmed to be complete by TLC. The mixture was washed twice with water and once with saturated brine, dried over anhydrous sodium sulfate, concentrated by column chromatography, dissolved in THF / water, and then 2N HCl was added. The reaction was stirred at room temperature, and the reaction was confirmed to be complete by TLC. The solvent was evaporated to dryness, and the mixture was purified by HPLC to obtain compound 13 in 51% yield. 1H NMR(300MHz,DMSO-d)δ7.13(t,J=7.5Hz,1H),7.04–6.87(m,2H),5.29(d,J=2.0Hz,2H),4.7 3–4.61(m,2H),4.18(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.87–2 .65(m,5H),2.56(d,J=13.0Hz,1H),2.07–1.93(m,4H),1.76–1.58(m,4H),1.58–1.37(m,4H ),1.36–1.25(m,4H),1.11(d,J=12.5Hz,1H),0.95(t,J=5.3Hz,3H).ESI-MSm / z:478.3[M+H] + .

[0102] Example 14

[0104] Compound 14 can be prepared by referring to the synthesis method of Example 13. 1 H NMR(300MHz,DMSO-d)δ7.15(t,J=7.2Hz,1H),7.04–6.91(m,2H),5.30(d,J=2.0Hz,2H),4.73–4.66 (m,2H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.26–3.13(m,2H),3.06(d,J=12.8Hz,1H),2 .87–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.07–1.90(m,4H),1.78–1.66(m,2H),1.61(dd,J=12.4, 1.9Hz,2H),1.57–1.38(m,4H),1.38–1.26(m,4H),1.17–1.04(m,4H),0.96(t,J=5.3Hz,3H).ESI-MS m / z:492.3[M+H] + .

[0105] Example 15

[0107] Compound 15 can be prepared by referring to the synthesis method of Example 13. 1H NMR(300MHz,DMSO-d)δ7.14(t,J=7.0Hz,1H),7.03–6.88(m,2H),5.30(d,J=1.1Hz,2H),4 .82–4.66(m,2H),4.15(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2 .85–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.10–1.91(m,2H),1.84–1.69(m,2H),1.68–1. 37(m,8H),1.31(dd,J=3.8,0.8Hz,4H),1.11(d,J=12.5Hz,1H),1.04–0.89(m,6H).ESI-MS m / z:506.3[M+H] + .

[0108] Example 16

[0110] Compound 16 can be prepared by referring to the synthesis method of Example 13. 1 H NMR(300MHz,DMSO-d)δ7.14(t,J=7.2Hz,1H),7.00–6.80(m,2H),5.30(d,J=1.0Hz,2H),4.83– 4.71(m,2H),3.77(d,J=4.9Hz,1H),3.69–3.55(m,2H),3.31(d,J=12.3Hz,1H),3.06(d,J=12.8 Hz,1H),2.85–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.09–1.90(m,4H),1.83–1.68(m,2H),1.6 7–1.37(m,6H),1.31(dd,J=3.8,0.8Hz,4H),1.11(d,J=12.5Hz,1H),1.00–0.78(m,9H).ESI-MS m / z:520.3[M+H] + .

[0111] Example 17

[0113] Synthetic route

[0115] O-TES-protected treprostyl (0.1 mmol), 1,2-ethylene glycol monoacetate (0.11 mmol), DCC (0.2 mmol), and DMAP (0.02 mmol) were dissolved in dichloromethane and reacted overnight. The reaction was confirmed to be complete by TLC. The solvent was evaporated, purified and concentrated by column chromatography, dissolved in THF / water, and 2N HCl was added. The mixture was stirred at room temperature, and the reaction was confirmed to be complete by TLC. The solvent was evaporated again, and the mixture was purified by HPLC to obtain compound 17. 1 H NMR(300MHz,DMSO-d)δ7.09(t,J=7.3Hz,1H),7.05–6.91(m,2H),4.78(s,2H),4 .39–4.13(m,5H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.84–2.65(m, 2H),2.56(d,J=13.0Hz,1H),2.09–1.90(m,7H),1.75–1.57(m,4H),1.57–1.37( m,4H),1.37–1.27(m,4H),1.11(d,J=12.5Hz,1H),0.94(t,J=5.3Hz,3H).ESI-MS m / z: 477.3 [M+H] + .

[0116] Example 18

[0118] Compound 18 can be prepared by referring to the synthesis method of Example 17. 1 H NMR(300MHz,DMSO-d)δ7.10(t,J=7.4Hz,1H),7.01–6.89(m,2H),4.77(d,J=2.2Hz,2 H),4.27–4.11(m,5H),3.77(d,J=4.9Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8 Hz,1H),2.84–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.14(d,J=1.4Hz,3H),2.09–1.9 1(m,7H),1.78–1.25(m,12H),1.11(d,J=12.5Hz,1H),0.99(t,J=5.3Hz,3H).ESI-MS m / z:513.3[M+Na] + .

[0119] Example 19

[0121] Compound 19 can be prepared by referring to the synthesis method of Example 17. 1H NMR(300MHz,DMSO-d)δ7.12(t,J=7.5Hz,1H),7.05–6.90(m,2H),4.87–4.61(m,2H),4.21–4.1 1(m,5H),3.77(d,J=4.9Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.84–2.66(m,2 H),2.56(d,J=13.0Hz,1H),2.05–1.95(m,7H),1.89(d,J=0.7Hz,4H),1.84–1.67(m,2H),1.67– 1.39(m,6H),1.31(dd,J=3.8,0.8Hz,4H),1.14(d,J=9.4Hz,1H),0.89(t,J=5.8Hz,3H).ESI-MS m / z:505.3[M+H] + .

[0122] Example 20

[0124] Compound 20 can be prepared by referring to the synthesis method of Example 17. 1 H NMR(300MHz,DMSO-d)δ7.14(t,J=7.2Hz,1H),7.04–6.88(m,2H),4.77(s,2H),4.38–4.14( m,5H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.86–2.65(m ,2H),2.56(d,J=13.0Hz,1H),2.39(d,J=16.5Hz,3H),2.08–1.94(m,4H),1.79–1.57(m,4H ),1.57–1.37(m,4H),1.37–1.26(m,4H),1.22–1.06(m,4H),0.95(t,J=5.8Hz,3H).ESI-MS m / z:513.3[M+Na] + .

[0125] Example 21

[0127] Compound 21 can be prepared by referring to the synthesis method of Example 17. 1H NMR(300MHz,DMSO-d)δ7.11(t,J=7.4Hz,1H),7.03–6.90(m,2H),4.79(s,2H),4.39–4 .14(m,5H),4.04(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.8 4–2.64(m,2H),2.63–2.48(m,2H),2.09–1.91(m,4H),1.85–1.67(m,2H),1.67–1.37( m,6H),1.31(dd,J=3.8,0.8Hz,4H),1.28–1.06(m,7H),0.97(t,J=5.4Hz,3H).ESI-MS m / z:505.3[M+H] + .

[0128] Example 22

[0130] Compound 22 can be prepared by referring to the synthesis method of Example 17. 1 H NMR(300MHz,DMSO-d)δ7.15(t,J=7.2Hz,1H),7.04–6.92(m,2H),4.86(s,2H),4.28–4.10( m,5H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.86–2.67(m ,2H),2.56(d,J=13.0Hz,1H),2.39(d,J=16.7Hz,3H),2.25–2.10(m,3H),2.09–1.90(m,4H ),1.83–1.69(m,2H),1.67–1.26(m,10H),1.18–1.03(m,4H),0.94(t,J=5.8Hz,3H).ESI-MS m / z:505.3[M+H] + .

[0131] Example 23

[0133] Compound 23 can be prepared by referring to the synthesis method of Example 23. 1H NMR(300MHz,DMSO-d)δ7.07(dd,J=7.9,7.1Hz,1H),7.01–6.90(m,2H),5.03–4.86(m,2H ),4.73(s,2H),4.29(d,J=4.9Hz,1H),4.07(d,J=2.5Hz,2H),3.69–3.49(m,3H),3.06(d ,J=12.8Hz,1H),2.86–2.67(m,2H),2.65–2.46(m,2H),2.23–2.02(m,4H),1.87(s,2H), 1.82–1.68(m,4H),1.66–1.38(m,6H),1.37–1.04(m,11H),0.94(t,J=5.8Hz,3H).ESI-MS m / z:563.4[M+H] + .

[0134] Example 24

[0136] Compound 24 can be prepared by referring to the synthesis method of Example 13. 1 H NMR(300MHz,DMSO-d)δ7.15(t,J=7.5Hz,1H),6.99(t,J=7.2Hz,1H),6.90(d,J=7.3Hz, 1H),5.82(s,1H),4.80–4.52(m,2H),4.18(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06 (d,J=12.8Hz,1H),2.85–2.62(m,5H),2.56(d,J=13.0Hz,1H),2.06–1.91(m,4H),1.80 –1.38(m,11H),1.38–1.25(m,4H),1.13(d,J=7.5Hz,1H),0.95(t,J=5.4Hz,3H).ESI-MS m / z:514.3[M+Na] + .

[0137] Example 25

[0139] Compound 25 can be prepared by referring to the synthesis method of Example 17. 1H NMR(300MHz,DMSO-d)δ7.09(t,J=7.4Hz,1H),7.04–6.90(m,2H),4.77(s,2H),4.32(d ,J=12.4Hz,1H),4.27–4.12(m,4H),4.04(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06 (d,J=12.8Hz,1H),2.88–2.65(m,5H),2.56(d,J=13.0Hz,1H),2.11–1.92(m,4H),1.80 –1.57(m,4H),1.57–1.27(m,8H),1.16(d,J=9.5Hz,1H),0.93(t,J=5.8Hz,3H).ESI-MS m / z:514.2[M+Na] + .

[0140] Example 26

[0142] Compound 26 can be prepared by referring to the synthesis method of Example 17. 1 H NMR(300MHz,DMSO-d)δ7.07(t,J=7.2Hz,1H),7.04–6.91(m,2H),4.88–4.70(m,2H),4.30–4.1 2(m,5H),4.04(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.88–2.65(m, 5H),2.56(d,J=13.0Hz,1H),2.23–2.08(m,3H),2.06–1.90(m,4H),1.84–1.70(m,2H),1.67–1 .37(m,6H),1.31(dd,J=3.8,0.8Hz,4H),1.14(d,J=7.4Hz,1H),0.89(t,J=5.8Hz,3H).ESI-MS m / z:528.3[M+Na] + .

[0143] Example 27

[0145] Compound 27 can be prepared by referring to the synthesis method of Example 17. 1H NMR(300MHz,DMSO-d)δ7.07(t,J=7.3Hz,1H),7.04–6.90(m,2H),4.87(s,2H),4.15(d,J =4.4Hz,5H),4.04(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.86–

[0146] 2.65(m,5H),2.56(d,J=13.0Hz,1H),2.04–1.96(m,4H),1.89(d,J=4.2Hz,4H),1.83–1.69(m,2H),1 .67–1.37(m,6H),1.31(dd,J=3.8,0.8Hz,4H),1.12(d,J=10.5Hz,1H),0.92(t,J=5.5Hz,3H).ESI-MS m / z:520.3[M+H] + .

[0147] Example 28

[0149] Compound 28 can be prepared by referring to the synthesis method of Example 1. 1 H NMR(300MHz,DMSO-d)δ7.11(t,J=7.2Hz,1H),7.04–6.76(m,2H),5.28–5.00(m,2H),4.74 (d,J=2.4Hz,2H),4.15(d,J=5.1Hz,1H),3.77(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2 .87–2.64(m,2H),2.56(d,J=13.0Hz,1H),2.39(d,J=18.8Hz,3H),2.09–1.92(m,4H),1.8 4–1.69(m,2H),1.69–1.22(m,18H),1.14(d,J=11.4Hz,1H),0.97(t,J=5.9Hz,6H).ESI-MS m / z:555.3[M+Na] + .

[0150] Example 29

[0152] Compound 29 can be prepared by referring to the synthesis method of Example 1. 1H NMR(300MHz,DMSO-d)δ7.17–7.05(m,1H),7.05–6.86(m,2H),5.31–4.97(m,2H),4.74 (d,J=2.4Hz,2H),4.15(d,J=5.1Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H) ,2.85–2.65(m,2H),2.56(d,J=13.0Hz,1H),2.47–2.28(m,3H),2.08–1.93(m,4H),1. 86–1.67(m,2H),1.66–1.22(m,20H),1.15(d,J=8.2Hz,1H),1.08–0.93(m,6H).ESI-MS m / z:569.3[M+Na] + .

[0153] Example 30

[0155] Compound 30 can be prepared by referring to the synthesis method of Example 1. 1 H NMR(300MHz,DMSO-d)δ7.08(dd,J=7.8,7.2Hz,1H),7.01–6.89(m,2H),5.28–5.00(m,2H),4.7 4(d,J=2.4Hz,2H),4.29(d,J=4.9Hz,1H),3.63(d,J=4.9Hz,1H),3.06(d,J=12.8Hz,1H),2.82– 2.65(m,2H),2.56(d,J=13.0Hz,1H),2.45–2.26(m,3H),2.07(d,J=13.0Hz,2H),1.84–1.64(m ,3H),1.64–1.34(m,8H),1.34–1.20(m,14H),1.17(d,J=5.2Hz,1H),1.04–0.94(m,6H).ESI-MS m / z:561.3[M+H] + .

[0156] Experimental Example 1: Pharmacokinetic Experiment of the Compound of this Application

[0157] (I) Experimental Instruments and Materials

[0158] High-speed refrigerated centrifuge, vortex oscillator (Vortex Genius3), high-speed centrifuge (Eppendorf 5415D), disposable syringes, pipettes (Eppendorf), EDTA-K2 vacuum blood collection tubes, and physiological saline.

[0159] All male SD rats used in the experiment were purchased from Yangzhou University. All rats in the oral administration group were fasted for 12 hours before administration, but had free access to water and food during administration.

[0160] (II) Experimental Procedure

[0161] The compound was dissolved in DMSO / solutol / water (10 / 10 / 80) to prepare a clear solution. The compound was administered via gavage at a dose of 25 mg / kg, and via tail vein at a dose of 5 mg / kg. Blood samples of 0.5 mL were continuously collected from the fundus venous plexus at 2 min, 10 min, 30 min, 1 h, 2 h, 3 h, 5 h, 8 h, 12 h, 16 h, and 24 h after tail vein administration and added to heparin tubes. Blood samples of 0.5 mL were continuously collected from the fundus venous plexus at 5 min, 15 min, 30 min, 1 h, 2 h, 3 h, 5 h, 8 h, 12 h, 16 h, and 24 h after gavage administration and added to heparin tubes. After centrifugation at 8000 rpm and 4 °C for 10 min, 0.15 mL of the supernatant plasma was collected and stored at -20 °C for LC-MS / MS analysis. Data were analyzed using a WinNolin non-compartmental model to obtain key pharmacokinetic parameters.

[0162] (III) Experimental Results

[0163] Table 1. Pharmacokinetic parameters of the compounds in the examples.

[0165] Pharmacokinetic data of the compounds in the examples show that, compared to treprostrinone's 17% oral bioavailability (Chinese Journal of New Drugs 2014, 23, 2585-2589), the half-life of 1 h and time to peak concentration of 0.5 h, the bioavailability of the compounds in the examples of this invention is significantly improved. The compounds of this invention possess excellent oral administration potential, while the time to peak concentration and half-life are also significantly improved.

[0166] Experimental Example 2: In vivo experiment of hypoxic pulmonary hypertension in rats

[0167] (I) Experimental Instruments and Materials

[0168] HX-200 animal ventilator. Male SD rats used in the experiment were all purchased from Yangzhou University, and physiological saline was used. All control groups were raised under normal conditions, while the intervention and model groups were raised in a low-pressure, low-oxygen chamber (50 kPa pressure, 10% oxygen concentration).

[0169] (II) Experimental Procedure

[0170] Compounds 8, 13, 19, and 25 were dissolved in DMSO / solutol / water (10 / 10 / 80) to prepare clear solutions. Starting from the second day of hypoxia, the intervention group received compounds 8, 13, 19, and 25 via gavage at a dose of 5 mg / kg. All rats were weighed weekly, and their survival status was recorded. Pulmonary artery pressure was measured after four weeks. Rats were anesthetized with chloral hydrate (100 g / L) (3 mL / kg), fixed in a supine position, and underwent tracheotomy. They were then assisted with ventilation using a small animal ventilator (60 breaths / min, tidal volume 5 mL, I:E ratio 4:5). The left third rib was freed, and a catheter with one end connected to a tension transducer was inserted into the pulmonary artery. Mean pulmonary artery pressure (mPAP) was recorded using a BL-420E biomechanical experimental system. Pleural and peritoneal fluid were examined and collected. Finally, blood was drawn from the abdominal aorta, and the rats were euthanized.

[0171] (III) Experimental Results

[0172] See attached Figure 1 Compared with the control group, the mPAP of rats in the model group was significantly increased, and the mPAP of the intervention groups treated with compounds 8, 13, 19 and 25 was lower than that in the model group.

[0173] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A prodrug of treprostrinil as shown in Formula I, or a pharmaceutically acceptable salt or stereoisomer thereof: in, R1 is hydrogen, methyl, or isopropyl; R2 is methyl, ethyl, n-propyl, isopropyl, tert-butyl, cyclopropyl, cyclohexyl, hydroxyl, methoxy, ethoxy, propoxy, methylamino, ethylamino, butylamino, 2-methylpropyl-1-amine, n-hexyl, n-heptyl, or n-octyl; n is 0, 1, 2, or 3.

2. The prodrug of treprostrinil according to claim 1, or a pharmaceutically acceptable salt or stereoisomer thereof, characterized in that, The compound of formula I is selected from any of the following structures:

3. A pharmaceutical composition comprising a prodrug of treprostrinil as described in any one of claims 1-2, or a pharmaceutically acceptable salt, stereoisomer, and pharmaceutically acceptable excipient thereof.

4. The pharmaceutical composition according to claim 3, characterized in that, The pharmaceutical composition is in the form of an oral, injectable, or inhaled dosage form.

5. The pharmaceutical composition according to claim 4, characterized in that: The pharmaceutical composition is an oral dosage form, which includes tablets, capsules, tablet-capsule forms, pills, tablet-containing forms, powders, syrups, elixirs, suspensions, solutions, emulsions, granules, or capsules.

6. The use of the prodrug of treprostrin according to any one of claims 1-2, or a pharmaceutically acceptable salt, stereoisomer, or pharmaceutical composition according to any one of claims 3-5 as a procyclosporine analog.

7. The use of the prodrug of treprostrinil according to any one of claims 1-2 or a pharmaceutically acceptable salt, stereoisomer or pharmaceutical composition according to any one of claims 3-5 in the preparation of a medicament for treating pulmonary hypertension, chronic arterial occlusive disease, and idiopathic pulmonary fibrosis.

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