Amino acid modified tetralones that selectively inhibit arachidonic acid, and preparation and use thereof

Abstract

The application discloses four kinds of tetra-cyclic compounds of four amino acids which selectively inhibit arachidonic acid (AA), and discloses a preparation method of the tetra-cyclic compounds and application of the tetra-cyclic compounds in treating arterial thrombosis diseases. Experiments prove that the arachidonic acid selective inhibitor has good anti-arterial thrombosis effect. Thus, the application provides an effective technical means for resisting arterial thrombosis.

Description

TECHNICAL FIELD

[0001] The present application relates to four kinds of amino acid modified tetra-cyclic compounds selectively inhibiting arachidonic acid (AA), a preparation method thereof and application in treating arterial thrombosis. Experiments prove that the AA selective inhibitor of the present application has good anti-arterial thrombosis effect. The present application belongs to the field of biological medicine. BACKGROUND

[0002] Arterial embolism has become one of the diseases with high morbidity and mortality. Arterial thrombosis is responsible for transient ischemic attack, acute coronary syndrome, myocardial infarction and atrial fibrillation. In atrial fibrillation, 18%-47% of patients have coronary artery disease, and about 20% of patients with atrial fibrillation accompanied by coronary artery disease receive percutaneous coronary intervention. Arterial thrombosis is also responsible for arterial thrombosis after artificial heart valve, arteriovenous fistula and other surgeries and unstable angina. For example, after liver transplantation surgery, patients face the risk of liver arterial thrombosis. In addition, patients with antiphospholipid syndrome also face the risk of arterial thrombosis. Arterial thrombosis is associated with platelet aggregation. Common inducers that induce platelet aggregation include platelet activating factor (PAF), adenosine diphosphate (ADP), thrombin (TH) and arachidonic acid (AA). It is an important direction of anti-arterial thrombosis drug research to find selective inhibitors of platelet activating factor, adenosine diphosphate, thrombin and arachidonic acid. The inventors screened four kinds of amino acid modified tetra-cyclic compounds with excellent selective inhibitory effect on platelet aggregation induced by arachidonic acid in research.

[0003] The four kinds of tetra-cyclic compounds show excellent anti-arterial thrombosis activity in a rat silk thread arterial thrombosis model. Based on these findings, the inventors propose the present application. SUMMARY

[0004] The technical problem to be solved by the present application is to provide four kinds of amino acid modified tetra-cyclic compounds selectively inhibiting arachidonic acid. Experiments prove that the four kinds of amino acid modified tetra-cyclic compounds prepared by the present application have excellent anti-arterial thrombosis effect. In order to achieve the above-mentioned purpose, the present application adopts the following five technical means.

[0005] The first technical means is to propose four kinds of amino acid modified tetra-cyclic compounds selectively inhibiting arachidonic acid with the following formula structure,

[0006]

[0007] In the formula, the amino acid AA is selected from L-Ala residue, L-Ile residue, L-Met residue or L-Cys residue.

[0008] The second technical means is to provide a method for preparing the amino acid modified tetrahydroisoquinoline compound, which comprises the following steps:

[0009] 1. preparing 3S-tetrahydro-β- carboline-3-carboxylic acid;

[0010] 2. preparing 3S-tetrahydro-β-carboline-3-carboxylic acid methyl ester;

[0011] 3. preparing 3S-2-Boc-Asp(OCH3)-tetrahydro-β-carboline-3-carboxylic acid methyl ester;

[0012] 4. preparing 3S-2-Asp(OCH3)-tetrahydro-β-carboline-3-carboxylic acid methyl ester;

[0013] 5. preparing acetylmethyl ester substituted tetrahydroisoquinoline compound;

[0014] 6. preparing acetic acid substituted tetrahydroisoquinoline compound;

[0015] 7. preparing acetyl-Ala-OBzl, acetyl-Ile-OBzl, acetyl-Met-OBzl and acetyl-Cys-OBzl substituted tetrahydroisoquinoline compound;

[0016] 8. preparing acetyl-Ala, acetyl-Ile, acetyl-Met and acetyl-Cys substituted tetrahydroisoquinoline compound.

[0017] The third technical means is to confirm the selective inhibition of arachidonic acid of the amino acid modified tetrahydroisoquinoline compound.

[0018] The fourth technical means is to confirm the selective inhibition of arachidonic acid induced platelet aggregation of the amino acid modified tetrahydroisoquinoline compound.

[0019] The fifth technical means is to confirm the excellent effect of the amino acid modified tetrahydroisoquinoline compound in preparing the medicine for inhibiting arterial thrombosis.

[0020] Compared with the prior art, the beneficial effects of the present application are:

[0021] The present application has prepared a kind of four kinds of amino acid modified tetrahydroisoquinoline compounds with selective inhibition of arachidonic acid, and through experiments, it has been found that the compound shows good activity of inhibiting arachidonic acid (AA) induced platelet aggregation, and has the effect of effectively inhibiting rats suffering from arterial thrombosis.The present application provides a new therapeutic drug for the treatment of arterial thrombosis, and enriches the selection of drugs for the treatment of thrombosis. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1Scheme for the synthesis of tetrahydro-β-carboline-3-carboxylic acid substituted with an acetylamino acid: i) CH2O, H2SO4; ii) SOCl2, CH3OH; iii) DCC, HOBt, N-methylmorpholine, Boc-Asp(OMe); iv) 4N hydrogen chloride in ethyl acetate; v) CH3OH, N-methylmorpholine; vi) 2N NaOH, CH3OH; vii) H2, palladium on carbon. DETAILED DESCRIPTION

[0023] In order to further illustrate the application, a series of examples is given below. These examples are purely illustrative and are only intended to describe the application in detail, and should not be interpreted as limiting the application.

[0024] Example 1 Preparation of 3S-tetrahydro-β-carboline-3-carboxylic acid (1)

[0025] To 400 mL of water was added slowly 0.2 mL of concentrated sulfuric acid. To the resulting aqueous solution of dilute sulfuric acid was added 5.0 g (24.5 mmol) of L-Trp and sonicated until the L-Trp was completely dissolved. To the resulting solution was added 10 mL of a 35% aqueous solution of formaldehyde. The reaction mixture was stirred at room temperature for 6 hours and thin layer chromatography (ethyl acetate / ether, 20 / 1) indicated that the L-Trp was gone and the reaction was terminated. Concentrated aqueous ammonia was added slowly to the reaction mixture and the pH was adjusted to 6. The reaction mixture was allowed to stand for 30 minutes. The resulting precipitate was filtered off and washed with water. The filtered off colorless solid was spread on a petri dish and allowed to dry in air to give 5.05 g (95%) of the title compound as a colorless solid. ESI (m / e): 217 [M+H] + .

[0026] Example 2 Preparation of 3S-tetrahydro-β-carboline-3-carboxylic acid methyl ester (2)

[0027] To a solution of 3.3 g (15 mmol) of 3S-tetrahydro-β-carboline-3-carboxylic acid in methanol was added slowly SOCl2at 0°C. The reaction mixture was stirred at 0°C for 6 hours. The reaction mixture was no longer releasing HCl gas and a solid was slowly precipitating. Thin layer chromatography (ethyl acetate / ether, 20 / 1) indicated that the 3S-tetrahydro-β-carboline-3-carboxylic acid was gone and the reaction was terminated. The reaction mixture was concentrated to dryness under reduced pressure. The residue was washed repeatedly with saturated aqueous sodium chloride solution and filtered to give 3.2 g (92%) of the title compound as a colorless powder. ESI (m / e) 231 [M+H] + .

[0028] Example 3 Preparation of 3S-[2-Boc-Asp(OCH3)]-tetrahydro-β-carboline-3-carboxylic acid methyl ester (3)

[0029] To a solution of 3.2 g (13.9 mmol) of 3S-tetrahydro-β-carboline-3-carboxylic acid methyl ester and 3.4 g (13.9 mmol) of Boc-Asp(OCH3) in 150 mL of dry tetrahydrofuran at 0 °C was added 2.0 g (14.8 mmol) of N-hydroxybenzotriazole (HOBt), 3.1 g (14.8 mmol) of dicyclohexylcarbodiimide (DCC). The reaction mixture was stirred at 0 °C for 30 minutes. The pH was then adjusted to 8 with N-methylmorpholine (NMM). The reaction mixture was stirred at 0 °C for 6 hours and thin layer chromatography (ethyl acetate / methanol, 20 / 1) indicated that 3S-tetrahydro-β-carboline-3-carboxylic acid methyl ester was consumed and the reaction was terminated. The reaction mixture was filtered and the filtrate was concentrated to dryness under reduced pressure. The residue was dissolved in 200 mL of ethyl acetate. The resulting solution was washed successively with 5% aqueous sodium bicarbonate solution (30 mL x 3), saturated aqueous sodium chloride solution (30 mL x 3), 5% aqueous hydrochloric acid solution (30 mL x 3), and saturated aqueous sodium chloride solution (30 mL x 3). The ethyl acetate layer was separated, dried over anhydrous sodium sulfate for 12 hours, filtered, and the filtrate was concentrated to dryness under reduced pressure to give 5.9 g (93%) of the title compound as a colorless powder. ESI (m / e) 460 [M+H] + .

[0030] Example 4 Preparation of 3S-[2-Asp(OCH3)]-tetrahydro-β-carboline-3-carboxylic acid methyl ester (4)

[0031] A solution of 5.9 g (12.9 mmol) of 3S-[2-Boc-Asp(OCH3)]-tetrahydro-β-carboline-3-carboxylic acid methyl ester in 50 mL of hydrogen chloride in ethyl acetate (4 N) was stirred at room temperature for 60 minutes. Thin layer chromatography (ethyl acetate / methanol, 20 / 1) indicated that 3S-[2-Boc-Asp(OCH3)]-tetrahydro-β-carboline-3-carboxylic acid methyl ester was consumed and the reaction was terminated. The reaction mixture was concentrated under reduced pressure and the residue was dissolved in 50 mL of ethyl acetate and concentrated under reduced pressure. This procedure was repeated five times to give 5.8 g (98%) of the title compound as a colorless powder. ESI (m / e) 460 [M+H] + .

[0032] Example 5 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid methyl ester (5)

[0033] A solution of 4.10 g (8.9 mmol) of 3S-[2-Asp(OCH3)]-tetrahydro-β- carbolin-3-carboxylic acid methyl ester in 30 mL of ethyl acetate was stirred at 30°C for 60 minutes to complete the cyclization reaction. 1.9 g (70%) of the title compound was obtained as a colorless powder. ESI (m / e) 327 [M+Na] + .

[0034] Example 6 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid (6)

[0035] A solution of 1.1 g (3.6 mml) of (3S,12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid methyl ester in 20 mL of methanol was dissolved at 0°C, and 2N aqueous sodium hydroxide solution was added dropwise to adjust the pH of the reaction solution to 12. The reaction solution was stirred for another 3 hours, and thin layer chromatography (ethyl acetate / methanol, 20 / 1) showed that (3S,12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid methyl ester disappeared, and the reaction was terminated. The reaction solution was first adjusted to pH 2 with dilute hydrochloric acid, and then concentrated under reduced pressure. 50 mL of distilled water was added to the residue, and the resulting mixture was extracted with ethyl acetate (30 mL x 3). The ethyl acetate extracts were combined and washed with saturated aqueous sodium chloride solution (30 mL x 3). The ethyl acetate extracts were dried over anhydrous sodium sulfate for 12 hours, filtered, and the filtrate was concentrated under reduced pressure to obtain 0.91 g (87%) of the title compound as a colorless powder. Rf = 0.35 (dichloromethane / methanol, 5 / 1). Mp: 228-232°C. f (c = 0.5, methanol). ESI (m / e) 313 [M-H] - . 1 ​H NMR (300 MHz, DMSO-d6): δ / ppm = 11.04 (s, 1 H), 8.23 (s, 1 H), 7.44 (d, J = 7.5 Hz, 1 H), 7.33 (t, J = 7.5 Hz, 1 H), 7.06 (t, J = 7.5 Hz, 1 H), 6.95 (t, J = 7.5 Hz, 1 H), 5.38 (d, J = 17.1 Hz, 1 H), 4.25 (dd, J = 3.9 Hz, J = 11.4 Hz, 1 H), 4.20 (d, J = 17.1 Hz, 1 H), 4.16 (d, J = 15.0 Hz, 1 H), 3.18 (dd, J = 3.3 Hz, J = 14.7 Hz, 1 H), 2.97 (t, J = 13.5 Hz, 1 H), 2.51 (d, J = 10.5 Hz, 2 H). 13 C NMR (75 MHz, DMSO-d6): δ / ppm = 172.44, 165.97, 165.05, 135.96, 129.84, 126.35, 120.86, 118.55, 117.53, 111.03, 105.70, 55.61, 52.35, 40.64, 26.43.

[0036] Example 7 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ala-OBzl (7a)

[0037] Using the reaction conditions and procedure of Example 2, 570 mg (1.82 mmol) of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4-b]indole-l,4-dione-3-acetic acid (6) and 630 mg (1.82 mmol) of Ala-OBzl gave 803 mg (95%) of the title compound as a colorless solid. ESI (m / e) 497 [M+Na] + .

[0038] Example 8 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ile-OBzl (7b)

[0039] Using the reaction conditions and procedure of Example 2, 570 mg (1.82 mmol) of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid (6) and 615 mg (1.82 mmol) of lie-OBzl afforded 798 mg (89%) of the title compound as a colorless solid. ESI (m / e) 539 [M+Na] + .

[0040] Example 9 Preparation of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Met-OBzl (7c)

[0041] Using the reaction conditions and procedure of Example 2, 570 mg (1.82 mmol) of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid (6) and 750 mg (1.82 mmol) of Met-OBzl afforded 900 mg (94%) of the title compound as a colorless solid. ESI (m / e) 557 [M+Na] + .

[0042] Example 10 Preparation of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Cys-OBzl (7d)

[0043] Using the reaction conditions and procedure of Example 2, 570 mg (1.82 mmol) of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetic acid (6) and 724 mg (1.82 mmol) of Cys-OBzl afforded 386 mg (50%) of the title compound as a colorless solid. ESI (m / e) 513 [M+Na] + .

[0044] Example 11 Preparation of (3S, 12aS)-2,3,6,7,12,12a-hexahydro-pyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ala (8a)

[0045] Dissolve 150 mg of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ala-OBzl (7a) in 15 mL of methanol and add 30 mg of palladium on carbon, continuously pass hydrogen gas, react for 2 hours, TLC test for disappearance of 7a, filter, rinse the filter cake with methanol repeatedly, concentrate the filtrate under reduced pressure, dry with ether to colorless powder, obtain 113 mg (94%) of the title compound as a colorless solid. R f = 0.35 (dichloromethane / methanol, 5 / 1), Mp: 193 °C. (c = 0.5, methanol). ESI (m / e) 383.1350 [M-H] - . IR (KBr): 3307, 3205, 2497, 1647, 1456, 1330, 1157 cm -1 . 1 HNMR (DMSO-d6, 300 MHz): δ = 10.93 (m, 1H), 8.200 (m, 2H), 7.444 (d, J = 7.5 Hz, 1H), 7.339 (d, J = 7.8 Hz, 1H), 7.072 (t, J = 7.2 Hz, 1H), 6.992 (t, J = 7.2 Hz, 1H), 5.397 (d, J = 6.8 Hz, 1H), 4.186 (m, 4H), 3.18 (m, 1H), 2.977 (m, 1H), 2.667 (m, 2H), 1.196 (d, J = 7.3 Hz, 3H). 13 C NMR (75 MHz, DMSO-d6): δ / ppm = 174.56, 168.94, 166.59, 165.09, 136.44, 130.29, 126.87, 121.47, 119.17, 118.08, 111.57, 106.31, 56.24, 52.16, 49.06, 47.99, 26.26, 17.84.

[0046] Example 12 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ile (8b)

[0047] Use the reaction conditions and operation of Example 11 to prepare 140 mg (97%) of the title compound from 175 mg of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Ile-OBzl as a colorless solid. R f= 0.30 (dichloromethane / methanol, 5 / 1), Mp: 172-176 °C. (c = 0.5, methanol). ESI (m / e) 425.1819 [M-H] - . IR (KBr): 3277, 3221, 2964, 1654, 1456, 1201 cm -1 . 1 HNMR (DMSO-d6, 300 MHz): δ / ppm = 10.925 (s, 1H), 8.161 (s, 1H), 8.063 (d, J = 8.1 Hz, 1H), 7.448 (d, J = 7.8 Hz, 1H), 7.336 (d, J = 7.8 Hz, 1H), 7.069 (t, J = 6.9 Hz, 1H), 6.989 (t, J = 7.2 Hz, 1H), 5.391 (d, J = 16.5 Hz, 1H), 4.201 (m, 4H), 3.165 (dd, J = 7.2 Hz, J = 14.4 Hz, 1H), 3.025 (m, 1H), 2.735 (m, 2H), 1.664 (m, 1H), 1.326 (m, 1H), 1.070 (m, 1H), 0.784 (m, 6H). 13 C NMR (75 MHz, DMSO-d6): δ / ppm = 173.36, 169.27, 166.58, 165.07, 136.45, 130.27, 126.88, 121.45, 119.14, 118.09, 111.55, 106.34, 56.76, 56.26, 52.18, 36.90, 26.65, 25.22, 15.82, 11.76.

[0048] Example 13 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Met (8c)

[0049] Using the reaction conditions and procedure of Example 11, 150 mg of (3S,12aS)-2,3,6,7,12,12a- hexahydropyrazino[l',2':l,6]pyrido[3,4-b]indole-l,4-dione-3-acetyl-Met-OBzl was used to prepare 110 mg of the title compound as a colorless solid. Rf = 0.35 (dichloromethane / methanol, 5 / 1), Mp: 122 °C. f = 0.30 (dichloromethane / methanol, 5 / 1), Mp: 172-176 °C. (c = 0.5, methanol). ESI (m / e) 425.1819 [M-H] - . IR (KBr): 3277, 3221, 2964, 1654, 1456, 1201 cm-1 . 1 H NMR (300 MHz, DMSO-d6): δ / ppm = 12.650 (s, 1 H), 10.954 (s, 1 H), 8.156 (m, 1 H), 7.442 (d, J = 7.5 Hz, 1 H), 7.335 (d, J = 6.9 Hz, 1 H), 7.331 (s, 1 H), 7.070 (t, J = 6.9 Hz, 1 H), 6.998 (t, J = 7.2 Hz, 1 H), 5.396 (d, J = 16.5 Hz, 1 H), 4.250 (m, 4 H), 3.174 (m, 1 H), 3.021 (t, J = 13.8 Hz, 1 H), 2.765 (m, 1 H), 2.670 (m, 1 H), 2.383 (m, 2 H), 2.048 (s, 3 H), 1.817 (m, 2 H). 13 C NMR (75 MHz, DMSO-d6): δ / ppm = 169.86, 169.41, 167.18, 166.60, 136.49, 130.34, 128.50, 127.08, 121.50, 119.17, 118.13, 111.58, 63.36, 56.35, 52.25, 51.46, 31.47, 30.08, 26.69, 15.06.

[0050] Example 14 Preparation of (3S,12aS)-2,3,6,7,12,12a-hexahydropyrazino[l',2':l,6]pyrido[3,4- b]indole-l,4-dione-3-acetyl-Cys (8d)

[0051] Using the reaction conditions and procedure of Example 11, 48 mg of the title compound were prepared from 80 mg of (3S,12aS)-2,3,6,7,12,12a- hexahydropyrazino[l',2':l,6]pyrido[3,4-b]indole-l,4-dione-3-acetyl-Cys-OBzl as a colorless solid. Rf= 0.20 (dichloromethane / methanol, 5 / 1), Mp: 189-194 °C. f = 0.20 (dichloromethane / methanol, 5 / 1), Mp: 189-194 °C. (c = 0.5, methanol). ESI (m / e) 415.1071 [M-H] - . IR (KBr): 3327, 2927, 1625, 1332, 1126, 744 cm -1 . 1H NMR (500 MHz, DMSO-d6): δ / ppm = 8.202 (m, 1H), 8.173 (m, 1H), 7.444 (d, J = 7.5 Hz, 1H), 7.340 (d, J = 7.5 Hz, 1H), 7.705 (t, J = 8.0 Hz, 1H), 6.996 (d, J = 7.5 Hz, 1H), 5.398 (d, J = 16.5 Hz, 1H), 4.270 (m, 2H), 4.184 (d, J = 17.0 Hz, 1H), 3.618 (m, 1H), 3.522 (m, 1H), 3.160 (m, 1H), 3.038 (t, J = 14.0 Hz, 1H), 2.756 (m, 2H). 13 CNMR (125 MHz, DMSO-d6): δ / ppm = 172.28, 169.31, 165.15, 136.34, 130.16, 121.49, 119.18, 111.53, 106.30, 72.70, 61.80, 60.67, 56.26, 47.99, 33.79, 32.72, 26.68, 25.31, 24.90.

[0052] Example 15 Evaluation of anti-platelet aggregation activity

[0053] Fresh porcine carotid artery blood was anticoagulated with 3.8% sodium citrate (1 / 9 by volume). Platelet-rich plasma (PRP) was obtained by centrifugation at 1000 g for 10 minutes and platelet-poor plasma (PPP) was obtained by centrifugation at 3000 g for 10 minutes. The platelet count in the PRP was adjusted to 300,000 / μL by dilution with PPP. 8a-d was dissolved in saline. To a cuvette was added 0.24 mL of the adjusted PRP, followed by 5 μL of saline or 5 μL of a saline solution of 8a-d (0.1 μM, 10 μM, 15 μM, 20 μM). The baseline absorbance was adjusted, and 5 μL of a saline solution of one of the four inducers was added to observe the maximum aggregation rate (Am) of the platelets within 5 minutes. The four inducers were platelet-activating factor (PAF, final concentration 50 μM), adenosine diphosphate (ADP, final concentration 500 μM), thrombin (TH, final concentration 50 IU / L), and arachidonic acid (AA, final concentration 7.5 mg / mL). The maximum aggregation rate was the value corresponding to the peak of the aggregation curve. The platelet aggregation curve was determined in sextuplicate for each concentration. The IC50 values of 8a-d for inhibition of platelet aggregation induced by PAF, ADP, TH, and AA were determined from the platelet aggregation curves. 50 (see Table 1). The data in Table 1 show that 8a-d has the smallest IC50 value for inhibition of AA-induced platelet aggregation, and that 8a-d is a selective inhibitor of AA. 50 value. The data in Table 1 show that 8a-d has the smallest IC50 value for inhibition of AA-induced platelet aggregation, and that 8a-d is a selective inhibitor of AA.

[0054] Table 1 IC of 8a-d to inhibit platelet aggregation induced by four inducers 50 (mean ± SD, μM)

[0055]

[0056]

[0057] n = 6

[0058] Example 16 Evaluation of Anti-arterial thrombosis activity

[0059] 1) A polyethylene tube was pulled into a thin tube with a bevel at one end, and the length was 10.0 cm. The tube was inserted into the right jugular vein (thicker tube) and the left carotid artery (thinner tube). The middle section of the polyethylene tube was 8.0 cm long, and the thrombus wire was pressed in the direction of the carotid artery. Heparin was filled in the tube before insertion.

[0060] 2) Male SD rats weighing 200 ± 20 g were acclimated to the environment and fasted for one day before surgery. They were randomly divided into a normal saline group (blank control, oral dose of 0.3 mL / 100 g, 10 rats), an aspirin group (positive control, oral dose of 167 μmol / kg, 10 rats), and a normal saline solution of 8a-d group (oral dose of 1 nmol / kg, 10 rats). Thirty minutes after oral administration, the rats were anesthetized with a 20% urethane solution (7 mL / kg) by intraperitoneal injection. Two minutes later, the surgery began. The rats were placed on a fixed plate in a supine position during the surgery. The skin on the neck was cut, and the right common carotid artery and left jugular vein were separated. A precision weighed silk thread was pressed under the blood vessels, and the distal end was ligated. A small incision was made at the distal end of the vein, and the tube was inserted into the vein end. Heparin was injected, and then the heparin syringe was removed. The thread was tied, and the proximal end of the artery was clamped with an artery clamp. A small incision was made at the distal end of the artery, and the artery end was ligated. After the thread was untied, the extracorporeal circulation bypass was established. After 15 minutes of circulation, the vein was cut to observe whether the blood circulation was normal. If the blood circulation was normal, the silk thread with thrombus was removed from the artery end. The uncoagulated blood was absorbed with filter paper. The weight of the silk thread with thrombus was accurately measured. The weight of the thrombus was obtained by subtracting the weight of the silk thread from the weight of the silk thread with thrombus. The data are shown in Table 2. The thrombus weight in the table indicates that the four aminosubstituted tetracyclic compounds represented by 8a-d can effectively inhibit arterial thrombosis in rats at an oral dose of 1 nmol / kg (p < 0.01 compared with normal saline). This is an unexpected technical effect.

[0061] Table 2 Effect of 8a-d on arterial thrombosis in rats

[0062]

[0063] a) p < 0.01 vs. saline; b) p > 0.05 vs. saline; n = 10.

Claims

1. Tetrahydropyrans of four amino acids modified selectively to inhibit arachidonic acid, characterized in that , said compound having the structure: wherein AA represents an amino acid selected from the group consisting of L-Ala, L-Ile, L-Met and L-Cys. , said method comprising the steps of:

2. Process for the preparation of the tetracyclic compounds according to claim 1, characterized in that 1) preparing 3S-tetrahydro-β-carboline-3-carboxylic acid; 2) preparing 3S-tetrahydro-β-carboline-3-carboxylic acid methyl ester; 3) preparing 3S-2-Boc-Asp(OCH3)-tetrahydro-β-carboline-3-carboxylic acid methyl ester; 4) preparing 3S-2-Asp(OCH3)-tetrahydro-β-carboline-3-carboxylic acid methyl ester; 5) preparing acetylmethyl ester substituted tetraloop compounds; 6) preparing acetoxy substituted tetraloop compounds; 7) preparing -CH2CO-Ala-OBzl, -CH2CO-Ile-OBzl, -CH2CO-Met-OBzl and -CH2CO-Cys-OBzl substituted tetraloop compounds; 8) preparing -CH2CO-Ala, -CH2CO-Ile, -CH2CO-Met and -CH2CO-Cys substituted tetraloop compounds.

3. Use of the tetraloop compound of claim 1 for the manufacture of a medicament for the selective inhibition of arachidonic acid.

4. Use of the tetraloop compound of claim 1 for the manufacture of a medicament for the selective inhibition of arachidonic acid-induced platelet aggregation.

5. Use of the tetraloop compound of claim 1 for the manufacture of a medicament for the treatment of arterial thrombosis. ​

Images