A class of aminosalicylic acid derivatives and their uses

Abstract

This invention discloses a class of aminosalicylic acid derivative compounds, their pharmaceutical compositions, and uses. The aminosalicylic acid derivatives of this invention can significantly improve ischemic symptoms in rats with a cerebral ischemia-reperfusion model, and these compounds have broad application prospects in the preparation of drugs for the prevention and treatment of stroke.

Description

Technical Field

[0001] This invention belongs to the pharmaceutical field and provides a class of aminosalicylic acid compounds, their preparation methods and pharmaceutical uses. These compounds can exert a therapeutic effect in protecting against cerebral ischemia-reperfusion injury. Background Technology

[0002] Acute ischemic stroke is a rapidly developing brain injury caused by the obstruction of blood supply to the brain due to ischemia. With the rapid aging of the population, the incidence of cerebral ischemia is showing a continuous upward trend, becoming the leading cause of disability and the second leading cause of death globally, further exacerbating the burden on society and families. The pathogenesis of cerebral ischemia is very complex, a multi-factorial, multi-mechanism, and multi-stage malignant cascade process. For many years, research on the related mechanisms of cerebral ischemia and reperfusion injury has included excitotoxicity, ion imbalance, oxidative stress, cortical diffuse depolarization, and inflammatory responses. Currently, commonly used anti-cerebral ischemia drugs mainly include antiplatelet aggregation drugs, thrombolytics, neuroprotective agents, and free radical scavengers. Although these drugs exert certain effects through different mechanisms, their use alone is unlikely to achieve very satisfactory efficacy. Domestic and international experts and scholars have conducted extensive research on the pathogenesis and prevention of cerebral ischemia and have made significant progress, but truly effective clinical prevention and treatment measures are still lacking. Therefore, how to adopt new strategies to research and develop novel and highly effective drugs for the prevention and treatment of cerebral ischemia with multiple functions is an important topic of widespread concern among medical scientists worldwide.

[0003] The PSD95-nNOS uncoupling agent ZL006, without affecting the physiological functions of NMDAR and nNOS, can reduce the pathological release of NO mediated by NMDAR, showing a significant neuroprotective effect on glutamate-stimulated neuronal damage, improving neurological deficits and reducing infarct volume in animals induced by middle cerebral artery occlusion (MCAO) reperfusion. ZL006 avoids the side effects such as learning and memory impairment and behavioral abnormalities that may be caused by direct intervention in NMDAR and nNOS, and has better safety.

[0004] Borneol is a commonly used traditional Chinese medicine, which can be divided into two main categories: natural borneol and synthetic borneol. Natural borneol is a processed product of the resin of the camphor tree. Traditional Chinese medicine believes that borneol is pungent and bitter in taste, cool in nature, and enters the heart, spleen, and lung meridians. It has the functions of opening the orifices and refreshing the mind, clearing heat and relieving pain, and promoting tissue regeneration. Borneol has the functions of "reviving the mind and opening the orifices," "aromatic circulation," and "guiding the medicine upwards," and is often used as a "guide drug" to enhance the therapeutic effect of other drugs. The *Compendium of Materia Medica* states that borneol "is weak when used alone, but effective when used as an adjuvant." Modern medical research shows that borneol has antibacterial, anti-inflammatory, antioxidant, anticoagulant, anti-myocardial ischemia, and analgesic effects.

[0005] The PSD95-nNOS uncoupling agent targets the central nervous system, but the ZL006 compound has high hydrophilicity, which is not conducive to drug penetration into the brain, resulting in limited distribution in the central nervous system. This invention, based on the principles of combination and prodrugs, utilizes a substituted carbonate to link ZL006 and borneol to synthesize an aminosalicylic acid-borneol derivative, which can significantly increase the concentration of ZL006 in the brain and has good pharmaceutical potential. Summary of the Invention

[0006] Technical problem solved: This invention provides a class of aminosalicylic acid borneol ester compounds. The most significant feature of this class of compounds is that they have brain-targeting effects and can significantly increase the concentration of ZL006 in the brain. They can be used to prepare drugs for the treatment of stroke.

[0007] Technical solution: A class of aminosalicylic acid compounds as shown in Formula I, or pharmaceutically acceptable salts thereof,

[0008]

[0009] Formula I

[0010] in,

[0011] R1 and R2 are selected from H, C1-C6 alkyl groups, and substituted alkyl groups;

[0012] R3 is selected from H, halogens, and C1-C6 alkyl groups;

[0013] The configuration of the chiral center in the molecule is either R configuration, S configuration, or racemic.

[0014] Preferably, R1 and R2 are selected from H, C1-C3 alkyl groups; R3 is selected from H, halogens;

[0015] More preferably, R1 is H or a methyl group; R2 is an H atom; R3 is selected from H, F, Cl, and Br;

[0016] More preferably, the compound is:

[0017]

[0018] Beneficial effects:

[0019] This patent describes a class of aminosalicylic acid compounds, which are characterized by brain-targeting activity and protective effects against cerebral ischemia-reperfusion injury, and can be used to prepare drugs for the treatment of stroke. Detailed Implementation

[0020] The following embodiments are provided to enable those skilled in the art to more fully understand the present invention, but do not limit the invention in any way.

[0021] Example 1: Synthesis of compound S1

[0022] Synthesis route:

[0023]

[0024] Synthesis process:

[0025] Intermediate A1: In a three-necked flask, 5.0 g (32.4 mmol) of 2-camphenol and 50 mL of dimethyl sulfoxide (DMSO) were added, followed by 1.3 g (32.4 mmol) of sodium hydride. The mixture was stirred at room temperature for 2 h, then 4.6 g (32.4 mmol) of ethyl chloroformate was added. The mixture was stirred overnight in an oil bath at 45 °C. The reaction was monitored by TLC until complete. After cooling to room temperature, the mixture was poured into 100 mL of ice water and filtered. The filter cake was washed successively with cold water and cold ethanol, and dried under vacuum to give 6.4 g of a white solid, with a yield of 76%.

[0026] Compound S1: Weigh ZL006 (1.25 g, 3.83 mmol) and sodium bicarbonate (336 mg, 4 mmol) into a reaction flask, add 15 mL of DMSO, stir at room temperature for 1 h, then add intermediate A1 (1.0 g, 3.83 mmol) and potassium iodide (16 mg, 0.13 mmol) sequentially, stir in an oil bath at 45 °C, monitor the reaction to completion by TLC, pour into 30 mL of water, extract three times with ethyl acetate, combine the organic phases, wash with saturated sodium chloride, dry with anhydrous sodium sulfate, concentrate under reduced pressure, and precipitate the crude product by silica gel column chromatography (petroleum ether / ethyl acetate 4:1) to give 950 mg of S1 as a white solid, yield 45%.

[0027] ESI-MS: 552.2 [M+H] + ;

[0028] 1H NMR (400 MHz, DMSO-d6): δ 10.48 (1H, m), 9.81 (1H, s), 7.46-7.49(1H, m), 7.40-7.41 (1H, m), 7.29-7.30 (1H, m), 7.10 (1H, m), 6.83-6.84 (1H,m), 6.23-6.25 (1H, m), 5.97 (1H, s), 4.74-4.76 (1H, m), 4.31-4.32 (2H, m), 2.27-2.32 (1H, m), 1.74-1.77 (1H, m), 1.64-1.71 (2H, m), 1.55-1.56 (3H, m),1.23-1.25 (1H, m), 1.16-1.19 (1H, m), 0.98-1.03 (1H, m), 0.84 (3H, s), 0.82(3H, s), 0.79 (3H, s).

[0029] Example 2: Synthesis of compound S2

[0030]

[0031] Synthesis process:

[0032] Intermediate A2: In a three-necked flask, 5.0 g (32.4 mmol) of 2-camphenol and 50 mL of dimethyl sulfoxide (DMSO) were added, followed by 1.3 g (32.4 mmol) of sodium hydride. The mixture was stirred at room temperature for 2 h, then 4.18 g (32.4 mmol) of chloromethyl chloroformate was added. The mixture was stirred overnight in an oil bath at 45 °C. The reaction was monitored by TLC until complete. After cooling to room temperature, the mixture was poured into 100 mL of ice water and filtered. The filter cake was washed successively with cold water and cold ethanol, and dried under vacuum to obtain 5.6 g of white solid A2, with a yield of 71%.

[0033] Compound S2: Weigh ZL006 (1.25 g, 3.83 mmol) and sodium bicarbonate (336 mg, 4 mmol) into a reaction flask, add 15 mL of DMSO, stir at room temperature for 1 h, then add intermediate A2 (0.94 g, 3.83 mmol) and potassium iodide (16 mg, 0.13 mmol) sequentially, stir in an oil bath at 45 °C, monitor the reaction with TLC until complete, pour into 30 mL of water, extract three times with ethyl acetate, combine the organic phases, wash with saturated sodium chloride, dry with anhydrous sodium sulfate, concentrate under reduced pressure, and precipitate the crude product by silica gel column chromatography (petroleum ether / ethyl acetate 4:1) to give 1.05 g of S2 as a white solid, yield 51%.

[0034] ESI-MS: 538.2 [M+H] + ;

[0035] 1 H NMR (400 MHz, DMSO-d6): δ 10.47 (1H, s), 9.79 (1H, s), 7.40 (1H, d,J=2), 7.29 (1H, m), 7.10 (1H, d, J=2), 6.83-6.84 (1H, m), 6.61 (2H, s), 6.23(1H, d, J=7.2), 5.97 (1H, s), 4.74-4.76 (1H, m), 4.32-4.33 (2H, m), 2.27-2.32(1H, m), 1.74-1.78 (1H, m), 1.65-1.72 (2H, m), 1.23-1.25 (1H, m), 1.17-1.19(1H, m), 0.99-1.04 (1H, m), 0.85 (3H, s), 0.83 (3H, s), 0.80 (3H, s).

[0036] Example 3: Determination of ZL006 concentration in brain tissue

[0037] 1. Preparation of sample solution

[0038] Weigh 30 mg of compound (S1) into a centrifuge tube, add DMA (less than 5% of the total volume) and Tween 80 (less than 5% of the total volume), dissolve in a 30°C water bath, and slowly add physiological saline to the mark to obtain a 1 mg / mL solution.

[0039] 2. Main Instruments and Software

[0040] LC-MS / MS: Includes Shimadzu LC-20AD high-performance liquid chromatograph, Shimadzu SIL-20AC autosampler, Shimadzu CTO-20A column oven, Shimadzu CBM-20A controller, Shimadzu SPD-20A UV-Vis detector; Applied Biosystems API 4000 mass spectrometer.

[0041] Table 1 Other major instruments and equipment:

[0042] Equipment Name Manufacturer model Analytical balance Mettler toledo XA105 Analytical balance Mettler toledo XP205 electronic scale Changshu Shuangjie Testing Instrument Factory T1000 model Disposable sterile syringes Shanghai Misawa Medical Industry Co., Ltd. 5mL, 2mL, 1mL High-speed refrigerated centrifuge DRAGONLAB D3024R centrifuge SCILOGEX D1008 High-speed refrigerated centrifuge Anhui Zhongke Zhongjia Scientific Instruments Co., Ltd. KDC-160HR Multi-tube vortex oscillator TARGIN VX-II

[0043] Table 2 Main Software / Data Systems

[0044] Software / Data System Name Version number use Analyst 1.5.2 API4000

[0045] 3. Test Methods

[0046] Nine ICR mice, weighing approximately 20g, were randomly divided into three groups of three. Compound S1 (20mg / kg) was administered via tail vein injection. Mice were fasted for 12 hours but allowed free access to water during the experiment. Mice were sacrificed at 15min, 30min, and 1h post-administration. Brain tissue was harvested, and capillaries were carefully dissected to make the tissue nearly white. Surface moisture was blotted dry with filter paper, and the tissue was weighed. A homogenate was prepared by adding three times the weight of physiological saline. After sonication for 10min to remove air bubbles, 100μL of the brain tissue homogenate was precisely pipetted into a 1.5mL centrifuge tube. Then, 10μL of internal standard solution and 300μL of methanol precipitant were added, mixed, vortexed for 1min, and centrifuged at 12000rpm for 10min. 150μL of the supernatant was precisely pipetted into 50μL of ultrapure water, and 10μL of the solution was injected for analysis using LC-MS / MS. The concentration of ZL006 in brain tissue was determined using a data system workstation.

[0047] Using the same method described above, the same dose of ZL006 was injected via the tail vein, and the intracerebral concentration of ZL006 was measured at 15 min, 30 min, and 1 h after administration. The experimental data are shown in Table 3 below.

[0048] Table 3. Comparison of intracerebral ZL006 concentrations after intravenous administration of S1 and ZL006.

[0049] Group In the brain of the ZL006 treatment group (µg / g) S1 administration group brain (µg / g) 15 min set 130 205 30 min set 95 121 1 h group 68 93

[0050] Example 4: Effect of S1 on focal cerebral ischemia-reperfusion injury

[0051] 1. Materials and Methods

[0052] 1.1 Laboratory Animals

[0053] Sprague-Dawley (SD) rats, male, weight: 250-280g, SPF grade.

[0054] 1.2 Experimental Methods

[0055] 1.2.1 Preparation of a focal cerebral ischemia-reperfusion model. Main steps: Rats were anesthetized by intraperitoneal injection of 10% chloral hydrate (350 mg / kg). The right external carotid artery was isolated, ligated, and severed. A nylon suture, approximately 18 mm long and enlarged at the cerebellar end, was slowly inserted through the stump of the external carotid artery along the common carotid and internal carotid arteries to obstruct the entrance of the middle cerebral artery, causing ischemia. After 2 hours of ischemia, the suture was removed, and reperfusion was performed for 24 hours. The model was considered successfully established when the animal exhibited Homer's sign and contralateral motor dysfunction upon awakening.

[0056] 1.2.2 Animal Grouping and Drug Administration Experimental animals were randomly divided into four groups: model group, positive control edaravone group (6 mg / kg), S1 (1 mg / kg) group, and S1 (0.1 mg / kg) group, with 10-12 animals in each group. The test drug and the positive control group were administered the drug via tail vein injection immediately after reperfusion, for a total of one administration.

[0057] The dosage volume for each group was 0.5 mL / 100 g.

[0058] 1.3.3 Neurological deficit score and determination of cerebral infarction volume

[0059] The modified Bederson 5-point scale was used to evaluate neurological deficit symptoms.

[0060] For the determination of cerebral infarction volume, after the animal underwent a final neurological deficit assessment, the brain was removed by decapitation. The olfactory brain, lower brainstem, and cerebellum were removed, and the remaining portion was immediately weighed wet. The brain was then sliced ​​into five pieces of approximately equal thickness along the coronal plane on ice and incubated in red tetrazolium dye at 37°C for 30 minutes. Normal brain tissue appeared deep red, while the infarcted area appeared pale white. The brain slices were then fixed in 10% formaldehyde, and the white tissue was carefully removed and weighed. The percentage of infarcted tissue weight to total brain weight was used as the infarct volume indicator.

[0061] 2 Results

[0062] 2.1 Effects on cerebral infarction volume and neurological deficit scores after ischemia-reperfusion

[0063] Compared with the model group, the drug groups significantly reduced the infarct volume in rats with cerebral ischemia-reperfusion injury (P<0.05); and improved the neurological deficit symptoms in rats. The results are shown in Table 4.

[0064] Table 4. Effects on infarct volume and neurological deficit score after ischemia-reperfusion ( ±S)

[0065] Group Cerebral infarction volume (%) Neurological deficit score (points) Model group 39.64±2.12 2.57±0.14 <![CDATA[Edaravone group (6 mg·kg -1 ).]]> 25.35±3.86** 1.85±0.25 <![CDATA[S1(1 mg·kg -1 )]]> 28.2±2.76** 2.1±0.29 <![CDATA[S1(0.1 mg·kg -1 )]]> 38.41±4.31 2.2±0.31

[0066] *P<0.05,**P<0.01, compared with the model group.

Claims

1. An aminosalicylic acid compound as shown in Formula S1, or a pharmaceutically acceptable salt thereof, characterized in that, The structure of the compound is as follows: 。 2. Use of the compound of claim 1 or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating stroke.

3. A pharmaceutical composition, characterized in that, It comprises the compound of claim 1 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.

Images