Flavanone derivatives, and preparation method and use thereof

Abstract

The invention relates to flavanone derivatives, and preparation method and use thereof, particularly relates to a compound of Formula I or a pharmaceutically acceptable salt thereof, a pharmaceutical composition comprising the same, a preparation method thereof, and use thereof for preventing or treating a mental disorder or a nervous system disease. The compound of the invention exerts significant activity of inhibiting microglial activation and neuroinflammation, can antagonize dopamine D2 receptor, improve the ethological change in multiple animal models for mental disorders, effectively inhibit neuroinflammation and demyelination, and can be used to prevent or treat a mental disorder and a nervous system disease. ##STR00001##

Claims

1. A compound of Formula (I) or a pharmaceutically acceptable salt thereof: ##STR00012## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 are independently selected from the group consisting of hydrogen, halogen, cyano, hydroxyl, amino, C.sub.1-6alkyl, C.sub.1-6alkoxy, C.sub.1-6alkylamino and aryl, optionally, wherein the C.sub.1-6alkyl, C.sub.1-6alkoxy, C.sub.1-6alkylamino and aryl are independently substituted with one or more substituents selected from the group consisting of halogen, amino and hydroxyl; X is a saturated or partially saturated alkylene containing 2-6 carbon atoms, optionally, wherein the alkylene is substituted by hydroxyl or methyl; Y is N or C(R), wherein R is selected from the group consisting of hydrogen, hydroxyl, amino, and C.sub.1-6alkyl; and Z is aryl or heteroaryl.

2. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 are independently selected from the group consisting of hydrogen, halogen, cyano, hydroxyl, amino, C.sub.1-6alkyl, C.sub.1-6alkoxy, C.sub.1-6alkylamino and 6-20-membered aryl.

3. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.3 is selected from the group consisting of hydrogen, halogen, C.sub.1-6alkyl and C.sub.1-6alkoxy, optionally, wherein the C.sub.1-6alkyl and C.sub.1-6alkoxy are independently substituted with one or more substituents selected from the group consisting of halogen, amino and hydroxyl.

4. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.8 is selected from the group consisting of hydrogen, halogen, C.sub.1-6alkyl and C.sub.1-6alkoxy, optionally, wherein the C.sub.1-6alkyl and C.sub.1-6alkoxy are independently substituted with one or more substituents selected from the group consisting of halogen, amino and hydroxyl.

5. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein Y is N or C(R), and R is selected from the group consisting of hydrogen, hydroxyl and methyl.

6. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein X is C.sub.2-6alkylene, optionally, wherein the C.sub.2-6alkylene is substituted by hydroxyl or methyl.

7. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein Z is aryl or heteroaryl containing 5-20 carbon atoms, optionally, wherein the aryl or heteroaryl is selected from the group consisting of phenyl, naphthyl, pyrrolyl, furyl, thienyl, imidazolyl, pyrazolyl, oxazolyi, isoxazolyl, thiazolyl, isothiazolyl, triazolyl, pyridyl, pyranyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, indolyl, benzofuryl, benzothienyl, benzoimidazolyl, benzopyrazolyl, benzoxazolyl, benzisoxazolyl, benzothiazolyl, benzoisothiazolyl, benzotriazolyl, quinolyl, benzopyranyl, benzopyrimidinyl, quinoxalinyl, benzopyridazinyl, benzotriazinyl and purinyl.

8. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein the compound is selected from the group consisting of: 5-hydroxy-2-(4-methoxyphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one; 5-hydroxy-2-(4-methylphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one; 5-hydroxy-2-(4-fluorophenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one; 5-hydroxy-2-methoxyphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-propoxy)-chroman-4-one; 5-hydroxy-2-methoxyphenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)-piperidin-1-yl)-butoxy)-chroman-4-one; 5-hydroxy-2-methoxyphenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)-piperidin-1-yl)-propoxy)-chroman-4-one; and 5-hydroxy-2-fluorophenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)- piperidin-1-yl)-butoxy)-chroman-4-one.

9. A pharmaceutical composition, comprising the compound or the pharmaceutically acceptable salt thereof according to claim 1, and optionally one or more pharmaceutically acceptable adjuvants.

10. A method for preparing the compound or the pharmaceutically acceptable salt thereof according to claim 1, comprising the following steps of: ##STR00013## ##STR00014## 1) Compound A and acetyl chloride are subjected to acylation reaction to produce Compound B; 2) Protective groups for the hydroxyl groups of Compound B are introduced to produce Compound C; 3) Compound C and Compound D are subjected to aldol condensation reaction to produce Compound E; 4) Compound E is subjected to ring-closure reaction to produce Compound F; 5) Compound F is deprotected to produce Compound G; 6) Compound G and Compound H are subjected to nucleophilic substitution to produce Compound I; and, 7) Compound I and Compound J are subjected to nucleophilic substitution to produce Compound of Formula I; wherein, PG represents a hydroxyl protecting group; L represents a leaving group of the nucleophilic substitution reaction; the other atoms or substituents have the same meanings as defined in claim 1.

11. A method for treating a mental disorder or a nervous system disease, comprising administering to a subject in need thereof an effective amount of the compound or the pharmaceutically acceptable salt thereof according to claim 1 or a pharmaceutical composition comprising the compound or the pharmaceutically acceptable salt thereof and optionally one or more pharmaceutically acceptable adjuvants; wherein, the mental disorder is selected from the group consisting of schizophrenia, depression, manic depressive disorder, cognitive disorder, anxiety disorder, stress related disorder, attention deficit hyperactivity disorder, tic disorder, and mental disorder associated with organic lesion; the nervous system disease is selected from the group consisting of neurodegenerative disease, Alzheimer's disease, Parkinson's disease, cerebrovascular disease, brain trauma, spinal cord injury, demyelinating disease, multiple sclerosis, inflammatory demyelinating polyneuropathy, ischemic leukoencephalopathy, hypoxic leukoencephalopathy and diabetic neuropathy.

12. A method for (1) inhibiting over activation or proliferation of microglial cells, (2) inhibiting the activity of dopamine receptor in a cell, (3) enhancing the activity of NMDA receptor in a cell, or (4) enhancing the content of myelin basic protein (MBP) in a cell, or reducing demyelination or pathological changes in white matter, comprising administering to the cell(s) an effective amount of the compound of Formula I or the pharmaceutically acceptable salt thereof according to claim 1 or a pharmaceutical composition comprising the compound or the pharmaceutically acceptable salt thereof and optionally one or more pharmaceutically acceptable adjuvants.

13. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 are independently selected from the group consisting of hydrogen, halogen, cyano, hydroxyl, amino and C.sub.1-4alkyl.

14. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 are hydrogen.

15. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.3 is selected from the group consisting of hydrogen, halogen, C.sub.1-4alkyl and C.sub.1-4alkoxy, optionally, wherein the C.sub.1-4alkyl and C.sub.1-4alkoxy are independently substituted with one or more substituents selected from the group consisting of halogen, amino and hydroxyl.

16. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.3 is selected from the group consisting of hydrogen, halogen, C.sub.1-2alkyl and C.sub.1-2alkoxy.

17. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.3 is selected from the group consisting of fluorine, methyl and methoxy.

18. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.8 is selected from the group consisting of hydrogen, halogen, C.sub.1-2alkyl and C.sub.1-2alkoxy.

19. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein R.sub.8 is selected from the group consisting of fluorine and methoxy.

20. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein Y is N or CH.

21. The compound or the pharmaceutically acceptable salt thereof according to claim 1, wherein X is 1,3-propylene or 1,4-butylene.

22. The method according to claim 11, wherein the mental disorder associated with organic lesion is selected from the group consisting of Alzheimer's disease, vascular dementia, mental disorder caused by brain trauma, mental disorder caused by intracranial infection, mental disorder caused by brain tumor, mental disorder caused by syphilis, epileptic mental disorder, mental disorder caused by HIV/AIDS.

Description

DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the result of the compounds of the invention for the inhibition of LPS+INF--induced activation of microglial cells (BV2 cells) and over-production and release of nitrogen monoxide (NO), wherein each concentration for each sample was repeated in 6 parallel wells, the experiment was repeated twice, and the data was expressed as MeanSE; .sup.##P<0.01, the model group was compared with the control group; *P<0.05, **P<0.01, the drug group was compared with the model group.

(2) FIG. 2 shows the antagonize activity of the compounds of the invention against dopamine D2 receptor (DRD2).

(3) FIG. 3 shows the effects of the compounds of the invention on spontaneous activity in MK-801-induced active schizophrenia model mice within 270 min, wherein the mice were tested for 60 min by an Open-Field Activity Monitoring System, and then, the control group (Con) was intraperitoneally injected with physiological saline, and the model group (M) and the drug groups (P4, P5, P6, P7) were intraperitoneally injected with MK-801; the mice of these groups were continuously monitored for spontaneous activity and center square activity within 210 minutes, and the mice were tested every 10 min, n=10 for each group.

(4) FIG. 4 shows the effects of the compounds of the invention on the total distance for spontaneous activity in MK-801-induced hyperlocomotive schizophrenia model mice within 210 min, wherein the data was expressed as MeanSE, n=10 for each group; .sup.##P<0.01, the model group was compared with the control group; *P<0.05, the drug group was compared with the Model group.

(5) FIG. 5 shows the effects of the compounds of the invention on the total distance for center square activity in MK-801-induced hyperlocomotive schizophrenia model mice within 210 min, wherein the data was expressed as MeanSE, n=10 for each group; .sup.##P<0.01, the model group was compared with the control group.

(6) FIG. 6 shows the effect of the compounds of the invention on the number of arm entries in Cuprizone model mice in Y-maze within 8 min, wherein the data was expressed as MeanSE, n=8 for each group, *P<0.05; **P<0.01; the drug group was compared with the Model group.

(7) FIG. 7 shows the effects of the compounds of the invention on spontaneous alternation in Cuprizone model mice in Y-maze within 8 min, wherein the data was expressed as MeanSE, n=8 for each group, .sup.#P<0.05, the model group was compared with the control group; *P<0.05, the drug group of the invention was compared with the Model group.

(8) FIG. 8 shows the effects of the compounds of the invention on total distance for spontaneous activity in Cuprizone model mice within 10 min, wherein the data was expressed as MeanSE, n=8 for each group, .sup.##P<0.01, the model group was compared with the control group; *P<0.05, the drug group of the invention was compared with the Model group.

(9) FIG. 9 shows the effect of the compounds of the invention on myelin basic protein (MBP) in the frontal contex of Cuprizone model mice, wherein (A) is a representative Western blot photo of MBP protein, S: small-dose group, 25 mg/kg; L: large-dose group, 50 mg/kg; and (B) is the quantitative result of MBP protein, wherein the data was expressed as MeanSE, n=4, .sup.##P<0.01, as compared with the control group; **P<0.01, as compared with the Model group.

(10) FIG. 10 shows the effect of the compounds of the invention on microglial cells in the brain of Cuprizone model mice (immunohistochemical staining), wherein the data was expressed as MeanSE, n=3, .sup.##P<0.01, as compared with the control group; *P<0.05, as compared with the Model group.

SPECIFIC MODES FOR CARRYING OUT THE INVENTION

(11) The embodiments of the invention are illustrated in detail by reference to the following examples. However, it is understood by those skilled in the art that the examples are used only for the purpose of illustrating the invention, rather than limiting the protection scope of the invention. In the case where the concrete conditions are not indicated in the examples, the examples are carried out according to conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used, for which the manufacturers are not indicated, are conventional products that can be purchased on the market or prepared by the well-known teachings.

(12) The structures of the compounds in the Examples are determined by conventional spectroscopic techniques (Infrared Spectrum, Ultraviolet Spectrum, Nuclear Magnetic Resonance or ESI-MS).

(13) A. Synthesis of the Compounds of the Invention

EXAMPLE 1

Synthesis of 5-hydroxy-2-(4-methoxyphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one (P1)

(14) ##STR00005##

(15) 1) Phloroglucinol (5.0 g, 40 mmol) was dissolved in a solution of carbon disulfide (50 ml) and nitrobenzene (15 ml), and anhydrous aluminium chloride (15.6 g, 120 mmol) was added. After stirring at room temperature for 10 min, a solution (10 ml) of acetyl chloride (4.23 ml, 60 mmol) in carbon disulfide was added to the reaction solution. The resultant solution was then heated to reflux at 50 C. for 1 h. Carbon disulfide was removed by distillation under reduced pressure. Hydrochloric acid (10 ml) and an ice-water mixture (50 ml) were added to the residue, and the resultant solution was extracted with ethyl acetate for 3 times (50 ml3). The organic phase was washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate, and ethyl acetate was removed by distillation under reduced pressure. The resultant residue was mixed with silica gel, and purified by silica gel column. The column was eluted with petroleum ether: ethyl acetate (2:1), to obtain a light yellow solid (5.71 g, yield: 85.7%).

(16) 2) The product (5.0 g) obtained in the step 1) was dissolved in acetone (50 ml), and anhydrous potassium carbonate (15 g) was added. Chloromethyl methyl ether (1.58 ml) was slowly added dropwise at room temperature within 20 min. The resultant mixture was then further stirred at room temperature for 2 h. Anhydrous potassium carbonate solid was filtered off, and acetone solution was removed by distillation under reduced pressure. Water (20 ml) was added to the residue, and the resultant solution was extracted with ethyl acetate for 3 times (30 ml3). The organic phase was washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate. The organic solvent was removed by distillation under reduced pressure. The residue was mixed with silica gel, and purified by silica gel column. The column was eluted with petroleum ether: ethyl acetate (15:1), to obtain a light yellow oil (about 4.3 g, yield: 56.4%).

(17) 3) The product (4 g) obtained in the step 2), sodium hydroxide (10 g), methanol (100 ml), and p-methoxybenzaldehyde (3.64 ml) were heated to reflux for 5 h, and cooled to room temperature. The solvent was removed by distillation under reduced pressure, distilled water (50 ml) was added, and the resultant solution was neutralized with 2% HCl. The resultant solution was extracted with ethyl acetate for 3 times (50 ml3), the organic phase was washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate. Ethyl acetate was removed by distillation under reduced pressure. The residue was mixed with silica gel, and purified by silica gel column. The column was washed with 5 column volumes of petroleum ether, and then eluted with petroleum ether: ethyl acetate (10:1), to obtain a yellow solid (4.98 g, yield: 85.2%).

(18) .sup.1H NMR (300 MHz, DMSO-d.sub.6): =12.39 (br s, 1H, OH-5), 7.67 (d, 2H, J=8.7 Hz, ArH), 7.53 (d, 2H, J=9.6 Hz, ArH), 7.01 (d, 2H, J=9.0 Hz, ArH), 5.28 (s, 2H, OCH.sub.2), 5.22 (s, 2H, OCH.sub.2), 3.81 (s, 3H, OCH.sub.3), 3.40 (s, 3H, OCH.sub.3), 3.40 (s, 3H, OCH.sub.3).

(19) 4) The product (2 g) obtained in the step 3), sodium acetate (8 g), and methanol (30 ml) were heated to reflux for 12 h, and cooled to room temperature. The solvent was removed by distillation under reduced pressure, distilled water (30 ml) was added, and the result solution was extracted with ethyl acetate for 3 times (20 ml3). The organic phase was washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate. Ethyl acetate was removed by distillation under reduced pressure. The residue was mixed with silica gel, and purified by silica gel column. The column was eluted with 4 column volumes of petroleum ether: ethyl acetate (10:1), and then eluted with petroleum ether: ethyl acetate (3:1), to obtain a colorless oil (1.63 g, yield: 81.5%).

(20) .sup.1H NMR (300 MHz, DMSO-d.sub.6): =7.44 (d, 2H, J=8.7 Hz, ArH), 6.97 (d, 2H, J=8.7 Hz, ArH), 6.36 (d, 1H, J=2.1 Hz, H-8), 6.33 (d, 1H, J=2.4 Hz, H-6), 5.50 (dd, 1H, J=12.9, 2.7 Hz, H-2), 5.23 (s, 2H, OCH.sub.2), 5.22 (s, 2H, OCH.sub.2), 3.77 (s, 3H, OCH.sub.3), 3.41 (s, 3H, OCH.sub.3), 3.38 (s, 3H, OCH.sub.3), 3.14 (dd, 1H, J=16.2, 12.9 Hz, H-3), 2.60 (dd, 1H, J=16.2, 2.7 Hz, H-3).

(21) 5) The product (1.5 g) obtained in the step 4), methanol (30 ml), and concentrated hydrochloric acid (1 ml) were heated to reflux for 30 min, and cooled to room temperature. The solvent was removed by distillation under reduced pressure, and the residue was suspended in a small amount of methanol, and poured into an ice-water mixture (100 ml). The resultant mixture was filtrated under reduced pressure, and the filter cake was oven-dried to obtain a white solid (0.87 g, yield: 72.3%).

(22) .sup.1H NMR (300 MHz, DMSO-d.sub.6): =12.14 (br s, 1H, OH-5), 10.78 (br s, 1H, OH-7), 7.44 (d, 2H, J=8.7 Hz, ArH), 6.97 (d, 2H, J=8.7 Hz, ArH), 5.90 (br s, 1H, H-8), 5.89 (br s, 1H, H-6), 5.50 (dd, 1H, J=12.6, 2.7 Hz, H-2), 3.77 (s, 3H, OCH.sub.3), 3.28 (dd, 1H, J=14.1, 12.6 Hz, H-3), 2.72 (dd, 1H, J=14.1, 3.0 Hz, H-3).

(23) 6) The product (0.8 g) obtained in the step 5), anhydrous potassium carbonate (3 g), acetone (20 ml), and 1,4-dibromobutane (1.2 g) were heated to reflux for 3 h, and cooled to room temperature. The anhydrous potassium carbonate solid was filtered off. The organic phase was mixed with silica gel, and purified by silica gel column. The column was eluted with petroleum ether: ethyl acetate (15:1), to obtain a yellow oil (0.61 g, yield: 54.5%).

(24) ESI+-MS: 423.1 [M+H].sup.+

(25) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.03 (br s, 1H, OH-5), 7.40 (d, 2H, J=8.7 Hz, ArH), 6.97 (d, 2H, J=8.7 Hz, ArH), 6.06 (d, 1H, J=2.4 Hz, H-8), 6.04 (d, 1H, J=2.4 Hz, H-6), 5.38 (dd, 1H, J=12.9, 3.0 Hz, H-2), 4.04 (t, 2H, J=6.0 Hz, H-1), 3.85 (s, 3H, OCH3), 3.49 (t, 2H, J=6.0 Hz, H-4), 3.11 (dd, J=17.1, 12.9 Hz, H-3), 2.80 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.68 (m, 4H, H.sub.2-2; Hz-6), 2.49 (t, 2H, J=7.2 Hz, H-5), 2.09 (m, 2H, H-3), 1.96 (m, 2H, H-2).

(26) 7) The product (0.6 g) obtained in the step 6), anhydrous potassium carbonate (2 g), potassium iodide (0.5 g), acetonitrile (10 ml), and 1-(2-methoxyphenyl)piperazine (0.68 g) were heated to reflux for 2 h, and cooled to room temperature. The anhydrous potassium carbonate solid was filtered off. The organic phase was mixed with silica gel, and purified by silica gel column. The column was eluted with petroleum ether: ethyl acetate (2:1) to obtain a yellow oil (0.15 g, yield: 19.7%).

(27) ESI.sup.+-MS: 532.9 [M +H].sup.+

(28) HR-Q-TOF-MS: 533.2712 [M+H].sup.+(calcd for C.sub.31H.sub.36N.sub.2O.sub.6, 533.2646).

(29) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.04 (br s, 1H, OH-5), 7.40 (d, 2H, J=8.7 Hz, ArH), 6.90 (m, 6H, ArH), 6.08 (d, 1H, J=2.1 Hz, H-8), 6.05 (br s, 1H, J=1.8 Hz, H-6), 5.38 (dd, 1H, J=12.9, 2.7 Hz, H-2), 4.03 (t, 2H, J=6.0 Hz, H-1), 3.88 (s, 3H, OCH.sub.3), 3.85 (s, 3H, OCH.sub.3), 3.11 (m, 5H, H.sub.2-4; H.sub.2-3; H-3), 2.80 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.68 (m, 4H, H.sub.2-2; H.sub.2-6), 2.49 (t, 2H, J=7.2 Hz, H-5), 1.85 (m, 2H, H-2), 1.70 (m, 2H, H-3). .sup.13C NMR (300 MHz, CDCl3): =195.9 (C-4), 167.5 (C-7), 164.1 (C-7), 162.9 (C-5), 160.1 (C-4), 152.3 (C-9), 141.4 (C-8), 130.5 (C-1), 127.7 (C-2, 6), 122.9 (C-12), 121.0 (C-10), 118.2 (C-11), 114.2 (C-3, 5), 111.3 (C-9), 103.1 (C-10), 95.6 (C-6), 94.6 (C-8), 79.0 (C-2), 68.3 (C-1), 58.1 (C-4), 55.4 (2-OCH.sub.3), 53.4 (C-3, 5), 50.6 (C-2, 6), 43.2 (C-3), 27.0 (C-2), 23.2 (C-3).

EXAMPLE 2

Synthesis of 5-hydroxy-2-(4-methylphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one (P2)

(30) ##STR00006##

(31) The operations were the same as those described in Example 1, and in the step 3), p-methylbenzaldehyde was used as a reactant.

(32) ESI+-MS: 517.2 [M +H].sup.+

(33) HR-Q-TOF-MS: 517.2766 [M+H].sup.+ (calcd for C.sub.31H.sub.36N.sub.2O.sub.5, 517.2697).

(34) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.03 (br s, 1H, OH-5), 7.36 (d, 2H, J=8.1 Hz, ArH), 7.26 (d, 2H, J=7.8 Hz, ArH),6.95 (m, 4H, ArH), 6.08 (d, 1H, J=2.7 Hz, H-8), 6.06 (br s, 1H, J=2.4 Hz, H-6), 5.40 (dd, 1H, J=12.9, 3.0 Hz, H-2), 4.03 (t, 2H, J=6.3 Hz, H-1), 3.88 (s, 3H, OCH.sub.3), 3.10 (m, 5H, H.sub.2-4; H.sub.2-3; H-3), 2.82 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.69 (m, 4H, H.sub.2-2; Hz-6), 2.49 (t, 2H, J=7.2 Hz, H-5), 2.40 (s, 3H, CH.sub.3), 1.83 (m, 2H, H-2), 1.71 (m, 2H, H-3). .sup.13C NMR (300 MHz, CDCl.sub.3): =195.8 (C-4), 167.5 (C-7), 164.1 (C-7), 162.9 (C-5), 152.3 (C-9), 141.4 (C-8), 138.8 (C-4), 135.5 (C-1), 129.5 (C-2, 6), 126.2 (C-3, 5), 122.9 (C-12), 121.0 (C-10), 118.2 (C-11), 111.3 (C-9), 103.1 (C-10), 95.6 (C-6), 94.6 (C-8), 79.1 (C-2), 68.3 (C-1), 58.1 (C-4), 55.4 (2-OCH.sub.3), 53.4 (C-3, 5), 50.6 (C-2, 6), 43.3 (C-3), 27.0 (C-2), 23.2 (C-3), 21.2 (CH.sub.3).

EXAMPLE 3

Synthesis of 5-hydroxy-2-(4-fluorophenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-butoxy)-chroman-4-one (P3)

(35) ##STR00007##

(36) The operations were the same as those described in Example 1, p-fluorobenzaldehyde was used as a reactant in the step 3), and the product P3 was a yellow oil.

(37) ESI+-MS: 520.8 [M+H].sup.+

(38) HR-Q-TOF-MS: 521.2506 [M+H].sup.+ (calcd for C.sub.30H.sub.33FN.sub.2O.sub.5, 521.2446).

(39) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.01 (br s, 1H, OH-5), 7.45 (m, 2H, ArH), 7.16 (m, 2H, J=7.8 Hz, ArH),6.95 (m, 4H, ArH), 6.10 (d, 1H, J=2.4 Hz, H-8), 6.06 (d, 1H, J=2.1 Hz, H-6), 5.40 (dd, 1H, J=13.2, 3.0 Hz, H-2), 4.03 (t, 2H, J=6.0 Hz, H-1), 3.88 (s, 3H, OCH3), 3.06 (m, 5H, H.sub.2-4; Hz-3; H-3), 2.82 (dd, 1H, J=17.1, 3.3 Hz, H-3), 2.68 (m, 4H, H.sub.2-2; Hz-6), 2.49 (t, 2H, J=7.5 Hz, H-5), 2.40 (s, 3H, CH.sub.3), 1.82 (m, 2H, H-2), 1.70 (m, 2H, H-3). .sup.13C NMR (300 MHz, CDCl3): =195.3 (C-4), 167.6 (C-7), 164.2 (C-7), 162.6 (C-5), 152.3 (C-9), 141.4 (C-8), 134.4 (C-4), 134.3 (C-1), 128.0 (C-2, 6), 122.9 (C-12), 121.0 (C-10), 118.2 (C-11), 116.0 (C-3), 115.7 (C-3), 111.3 (C-9), 103.0 (C-10), 95.7 (C-6), 94.7 (C-8), 78.5 (C-2), 68.3 (C-1), 58.1 (C-4), 55.4 (2-OCH.sub.3), 53.5 (C-3, 5), 50.6 (C-2, 6), 43.4 (C-3), 27.0 (C-2), 23.2 (C-3).

EXAMPLE 4

Synthesis of 5-hydroxy-2-(4-methoxyphenyl)-7-(4-(4-(2-methoxyphenyl)-piperazin-1-yl)-propoxy)-chroman-4-one (P6)

(40) ##STR00008##

(41) The operations were the same as those described in Example 1, 1,3-dibromopropane was used as an reactant in the step 6), and the product P3 was a yellow oil.

(42) ESI+-MS: 519.0 [M+H].sup.+

(43) HR-Q-TOF-MS: 519.2548 [M+H].sup.+ (calcd for C.sub.30H.sub.34N.sub.2O.sub.6, 519.2490).

(44) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.04 (br s, 1H, OH-5), 7.40 (d, 2H, J=8.4 Hz, ArH), 6.96 (m, 6H, ArH), 6.09 (br s, 1H, H-8), 6.08 (br s, 1H, H-6), 5.38 (dd, 1H, J=12.9, 2.4 Hz, H-2), 4.08 (t, 2H, J=6.0 Hz, H-1), 3.88 (s, 3H, OCH3), 3.85 (s, 3H, OCH.sub.3), 3.11 (m, 5H, Hz-3; Hz-3; H-3), 2.80 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.69 (m, 4H, H.sub.2-2; H.sub.2-6), 2.58 (t, 2H, J=7.2 Hz, H-5), 2.03 (m, 2H, H-2). .sup.13C NMR (300 MHz, CDCl.sub.3): =196.0 (C-4), 167.2 (C-7), 164.1 (C-7), 162.9 (C-5), 160.1 (C-4), 152.2 (C-9), 140.8 (C-8), 130.4 (C-1), 127.7 (C-2, 6), 123.3 (C-12), 121.1 (C-10), 118.4 (C-11), 114.2 (C-3, 5), 111.2 (C-9), 103.2 (C-10), 95.6 (C-6), 94.6 (C-8), 79.0 (C-2), 66.4 (C-1), 55.4 (2-OCH.sub.3), 54.8 (C-3), 53.2 (C-5, 9), 49.8 (C-2, 6), 43.2 (C-3), 29.7 (C-2).

EXAMPLE 5

Synthesis of 5-hydroxy-2-(4-methoxyphenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)-piperidin-1-yl)-butoxy)-chroman-4-one (P5)

(45) ##STR00009##

(46) The operations were the same as those described in Example 1, 6-fluoro-3-(4-piperidinyl)-1,2-benzisoxazole was used as an reactant in the step 7), and the product P5 was a yellow oil.

(47) ESI+-MS: 560.8 [M+H].sup.+

(48) HR-Q-TOF-MS: 561.2447 [M+H].sup.+ (calcd for C.sub.32H.sub.33FN.sub.2O.sub.6, 561.2395).

(49) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.05 (br s, 1H, OH-5), 7.40 (dd, 1H, J=8.7, 5.1 Hz, ArH), 7.44 (d, 2H, J=8.7 Hz, ArH), 7.25 (dd, 2H, J=8.7, 2.1 Hz, ArH), 7.07 (dt, 1H, J=9.0, 2.1 Hz, ArH), 6.97 (d, 2H, J=8.7 Hz, ArH), 6.08 (d, 1H, J=2.1 Hz, H-8), 6.06 (br s, 1H, J=2.4 Hz, H-6), 5.40 (dd, 1H, J=13.2, 3.0 Hz, H-2), 4.03 (t, 2H, J=6.0 Hz, H-1), 3.85 (s, 3H, OCH.sub.3), 3.12 (m, 4H, H.sub.2-4; H-8; H-3), 2.81 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.47 (t, 2H, J=7.2 Hz, H-6), 2.08 (m, 6H, H.sub.2-7; H.sub.2-9; H.sub.2-10), 1.83 (m, 2H, H-2), 1.70 (m, 2H, H-3). .sup.13C NMR (300 MHz, CDCl3): =195.9 (C-4), 167.5 (C-7), 164.1 (C-6), 162.9 (C-5), 161.1 (C-9), 160.1 (C-4), 130.5 (C-1), 127.7 (C-2, 6), 122.7 (C-8), 122.5 (C-6), 117.3 (C-3), 114.4 (C-3, 5), 112.5 (C-9), 112.1 (C-9), 103.1 (C-10), 97.6 (C-7), 97.2 (C-7), 95.5 (C-6), 94.6 (C-8), 79.0 (C-2), 68.3 (C-1), 58.3 (C-4), 55.4 (OCH.sub.3), 53.5 (C-6, 10), 43.2 (C-3), 34.6 (C-8), 30.5 (C-7, 9), 27.0 (C-2), 23.3 (C-3).

EXAMPLE 6

Synthesis of 5-hydroxy-2-(4-fluorophenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)-piperidin-1-yI)-butoxy)-chroman-4-one (P4)

(50) ##STR00010##

(51) The operations were the same as those described in Example 1, p-fluorobenzaldehyde was used as a reactant in the step 3), 6-fluoro-3-(4-piperidinyl)-1,2-benzisoxazole was used as an reactant in the step 7), and the product was a yellow oil.

(52) ESI+-MS: 548.8 [M+H].sup.+

(53) HR-Q-TOF-MS: 549.2273 [M+H].sup.+ (calcd for C.sub.31H.sub.30F.sub.2N.sub.2O.sub.5, 549.2196).

(54) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.04 (br s, 1H, OH-5), 7.40 (dd, 2H, J=8.7, 5.1 Hz, ArH), 7.44 (m, 2H, ArH), 7.24 (dd, 2H, J=8.7, 2.1 Hz, ArH), 7.09 (m, 4H, ArH), 6.08 (d, 1H, J=2.1 Hz, H-8), 6.05 (br s, 1H, J=2.4 Hz, H-6), 5.40 (dd, 1H, J=12.6, 3.0 Hz, H-2), 4.03 (t, 2H, J=6.0 Hz, H-1), 3.06 (m, 4H, Hz-4; H-8; H-3), 2.80 (dd, 1H, J=17.1, 3.0 Hz, H-3), 2.48 (t, 2H, J=7.2 Hz, H-6), 2.05 (m, 6H, H.sub.2-7; H.sub.2-9; H.sub.2-10), 1.83 (m, 2H, H-2), 1.70 (m, 2H, H-3). .sup.13C NMR (300 MHz, CDCl.sub.3): =195.9 (C-4), 167.5 (C-7), 164.1 (C-4), 162.6 (C-5), 161.0 (C-9), 134.3 (C-4), 134.3 (C-1), 128.0 (C-2, 6), 122.7 (C-8), 122.5 (C-6), 117.3 (C-9), 115.9 (C-3), 115.7 (C-3), 112.5 (C-1), 112.1 (C-7), 103.0 (C-10), 97.2 (C-5), 95.7 (C-6), 94.6 (C-8), 78.5 (C-2), 68.3 (C-1), 58.2 (C-4), 53.4 (C-6, 10), 30.4 (C-7, 9), 43.3 (C-3), 34.5 (C-8), 26.9 (C-2), 23.2 (C-3).

EXAMPLE 7

Synthesis of 5-hydroxy-2-(4-methoxyphenyl)-7-(4-(4-(6-fluoro-benzo[d]isoxazol-3-yl)-piperidin-1-yl)-propoxy)-chroman-4-one (P7)

(55) ##STR00011##

(56) The operations were the same as those described in Example 1, 1,3-dibromopropane was used as an reactant in the step 6), 6-fluoro-3-(4-piperidinyl)-1,2-benzisoxazole was used as an reactant in the step 7), and the product was a yellow oil.

(57) ESI+-MS: 546.9 [M+H].sup.+

(58) HR-Q-TOF-MS: 547.2309 [M+H].sup.+ (calcd for C.sub.31H.sub.31FN.sub.2O.sub.6, 547.2239).

(59) .sup.1H NMR (300 MHz, CDCl.sub.3): =12.04 (br s, 1H, OH-5), 7.72 (dd, 1H, J=8.4, 5.1 Hz, ArH), 7.39 (d, 2H, J=8.4 Hz, ArH), 7.25 (m, 1H, ArH), 7.06 (dt, 1H, J=9.0, 2.1 Hz, ArH), 6.96 (d, 2H, J=8.4 Hz, ArH), 6.10 (br s, 1H, H-8), 6.08 (br s, 1H, H-6), 5.40 (dd, 1H, J=12.9, 2.1 Hz, H-2), 4.08 (t, 2H, J=6.0 Hz, H-1), 3.84 (s, 3H, OCH.sub.3), 3.11 (m, 4H, H.sub.2-3; H-8; H-3), 2.81 (dd, 1H, J=17.1, 2.7 Hz, H-3), 2.60 (t, 2H, J=7.2 Hz, H-5), 2.09 (m, 8H, H.sub.2-2; H.sub.2-6; H.sub.2-8; H.sub.2-9). .sup.13C NMR (300 MHz, CDCl3): =196.0 (C-4), 167.4 (C-7), 164.1 (C-6), 162.9 (C-5), 161.0 (C-9), 160.0 (C-4), 130.4 (C-1), 127.7 (C-2, 6), 122.7 (C-8), 122.6 (C-6), 117.3 (C-3), 114.2 (C-3, 5), 112.5 (C-9), 112.2 (C-9), 103.1 (C-10), 97.6 (C-7), 95.6 (C-6), 94.6 (C-8), 79.0 (C-2), 66.7 (C-1), 55.4 (OCH.sub.3), 55.0 (C-3), 53.5 (C-5, 9), 43.2 (C-3), 34.5 (C-7), 30.4 (C-6, 8), 30.0 (C-2), 26.5 (C-3).

(60) B. Pharmacological Study on the Compounds of the Invention

EXPERIMENTAL EXAMPLE 1

Effects of the Compounds of the Invention on LPS+INF--Induced Inflammatory Response in Microglial Cells

(61) Objective: microglial activation and neuroinflammation are the important pathogenic mechanisms of many central nervous system diseases. Inflammation-inducing substances, bacterial endotoxin (lipopolysaccharide (LPS)) and interferon- (IFN-), can stimulate the production of pre-inflammatory cytokines in an organism which trigger an inflammatory cascade, and further activate inflammatory cells such as microglial cells, to release inflammatory mediators such as nitrogen monoxide (NO), thereby forming an inflammatory network. In this experiment, the novel compounds synthesized in the invention were studied for their inhibitory effects on inflammation in microglial cells, by establishing an LPS+INF--induced inflammation model in microglial cells (BV2 cells).

(62) Methods: BV2 cells (mouse microglial cell line) in exponential growth phase were seeded on a 96-well plate (the culture solution was 90% DMEM+10% fetal bovine serum), and were incubated in a 37 C., 5% CO.sub.2 incubator. 24 hrs later, the compounds were added at different concentrations, and the culture solution was discarded after incubation for 24 hrs. LPS (100 g/ml)+INF- (1 ng/ml) were added. 24 hrs later, the supernatant was collected. The stable metabolic product (nitrite) of NO was used as an index for determining NO, and was determined by Griess Kit.

(63) Results: as shown in FIG. 1, in LPS+INF- induced BV2 cells (microglial cells), the production and release of the inflammatory mediator NO were significantly increased. All the compounds of the invention had an inhibitory effect on over-production and release of NO in LPS+INF--induced BV2 cells, indicating that these compounds could significantly antagonize neuroinflammation.

(64) The result showed that the compounds of the invention could be used in the prevention and treatment of a mental disorder such as schizophrenia, and depression, and a nervous system disease such as neurodegenerative disease (e.g. Alzheimer's disease, Parkinson's disease), cerebrovascular disease, brain trauma, spinal cord injury, demyelinating disease, multiple sclerosis, and inflammatory demyelinating polyneuropathy.

EXPERIMENTAL EXAMPLE 2

Effects of the Compounds of the Invention Against Activity of Dopamine D2 Receptor

(65) Objective: positive symptoms (hallucination, delusion, etc.) in patients with schizophrenia may be associated with dopamine (DA) hyperfunction in subcortical limbic system, and antipsychotic drugs, which block Dopamine D2 Receptor (DRD2), can effectively control positive symptoms of schizophrenia. By establishing a cell line co-transfected with DRD2 and G16, the activated DRD2 can activate G16 protein, thereby activating phospholipase C (PLC) to produce inositol 1,4,5-triphosphate (IP.sub.3) and diacylglycerol (DAG), wherein IP.sub.3 can bind to the IP.sub.3 receptor on endoplasmic reticulum and mitochondria, resulting in intracellular calcium release. Therefore, the determination of a change in intracellular calcium can be used as a method for detecting the activated state of DRD2.

(66) Fluo-4/AM was a calcium fluorescent probe indicator for determining calcium ions. In this experiment, a Fluo-4 fluorescence method was used to determine the level of activated G protein by measuring the fluorescence intensity excited by intracellular calcium ions. If a compound could activate DRD2, the calcium influx was enhanced; on the contrary, if a compound could antagonize DRD2, the calcium influx was reduced.

(67) Methods: HEK293 cells stably expressing DRD2/G16 (a human embryonic kidney cell line, derived from Shanghai Institute of Materia Medica, Chinese Academy of Sciences) were seeded in a 96-well plate (the culture solution was 90% DMEM+10% fetal bovine serum), and incubated overnight. The culture solution was pipetted off, and a freshly prepared dye Fluo-4/AM was added. The cells were incubated in a 37 C. incubator for 40 min. The dye was completely pipetted off. After the cells were washed with a freshly prepared calcium buffer, a calcium buffer (50 l) dissolved with a test drug was added. FlexStation II instrument was used in the determination. A calcium buffer (25 l) dissolved with a known agonist was added automatically by the instrument at the fifteenth second, and the fluorescence value at 525 nm (an excitation wavelength of 485 nm) was finally read. Dopamine was used as agonist, Eticlopride (D2 receptor antagonist) was used as antagonist, and the cell response (% Response) of each sample at each concentration was calculated by the following formula: % Response=(L.sub.SampleL.sub.Blank)/(L.sub.DopamineL.sub.Blank), wherein L.sub.Sample represents the detected signal value of a test sample, L.sub.Blank represents the detected signal value as completely inhibited by Eticlopride, and L.sub.Dopamine represents the detected signal value after the stimulation of the DMSO group with 50 nM Dopamine (agonist). IC.sub.50 value was calculated by GraphPad Prism.

(68) Results: as seen from Table 1 and FIG. 2, the compounds P1P7 of the invention could inhibit the activity of dopamine D2 receptor (DRD2) with a certain dosage-effect. The result showed that the compounds of the invention could be used in the prevention and treatment of a mental disorder such as schizophrenia.

(69) TABLE-US-00001 TABLE 1 IC.sub.50 value of a part of compounds of the invention for inhibiting dopamine D2 receptor Test compound IC.sub.50 (M) 95% confidence limit (M) P1 2.052 10.sup.7 1.298 10.sup.7~3.244 10.sup.7 P2 3.460 10.sup.7 1.800 10.sup.7~6.652 10.sup.7 P3 5.727 10.sup.8 3.590 10.sup.8~9.134 10.sup.8 P6 2.200 10.sup.7 1.211 10.sup.7~3.995 10.sup.7 P5 5.129 10.sup.8 3.336 10.sup.8~7.886 10.sup.8 P4 8.767 10.sup.8 4.919 10.sup.8~1.563 10.sup.7 P7 1.155 10.sup.7 6.827 10.sup.8~1.954 10.sup.7

EXPERIMENTAL EXAMPLE 3

Effects of the Compounds of the Invention onNMDA Receptor Antagonist-Induced Schizophrenia Mouse Model

(70) Objective: Glutamatergic hypofunction is one of the pathogenesis for mental disorders such as schizophrenia. N-methyl-D-aspartic acid (NMDA) receptor antagonists can induce schizophrenia-like effects. In this experiment, a hyperlocomotion schizophrenia model in mice induced by dizocilpine (MK-801), a NMDA receptor antagonist, was used to investigate the in vivo activity of the compounds P6, P5, P4 and P7 of the invention.

(71) Methods: SPF grade inbred Balb/c male mice with no special pathogens (purchased from Laboratory Animal Center of Capital Medical University), weighed (202) g, were randomly divided into a control group, a model group, and drug groups. The mice were adapted to the rearing environment for one week, and then were intragastrically administered for 3 days, wherein the control group and model group were intragastrically administered with physiological saline, and on Day 4, the mice were administered prior to test, and then were tested for 60 min in an Open-Field Activity Monitoring System. The control group was then intraperitoneally injected with physiological saline, the model group and the drug groups were intraperitoneally injected with a solution (0.6 mg/kg) of a NMDA receptor antagonist dizocilpine (MK-801), and the mice of these groups were further monitored for spontaneous activity and center square activity within 210 minutes, wherein spontaneous activity was used to reflect the positive symptom of rapid motion in schizophrenia, and center square activity was used to evaluate the anxiety status of schizophrenia.

(72) Results: open field test was used to monitor the spontaneous activity of mice, and the result showed that as compared with the control group, the mice in the MK-801 model group had a prolonged total distance of spontaneous activity and a prolonged distance of center square activity within 210 min; intragastrical administration of the compounds P6, P5, and P7 of the invention could shorten the total distance of spontaneous activity and the distance of center square activity (FIG. 3, FIG. 4, FIG. 5, and Table 2). The result showed that the compounds of the invention could alleviate the positive symptoms and anxiety state of schizophrenia.

(73) TABLE-US-00002 TABLE 2 Effects of the compounds of the invention on the total distance of spontaneous activity and the distance of center square activity in MK-801-induced hyperlocomotion schizophrenia model in mice within 210 min (open-field test) Dose Total distance Distance of central Group (mg/kg) traveled (cm) district activity (cm) Normal control 15979 2228 1903 627 Model 49932 4059.sup.## 12248 955.sup.## Model + P6 50 46922 2233 10181 2110 Model + P5 50 30914 3351* 9211 1845 Model + P4 50 39222 4300 11098 1422 Model + P7 50 37051 4308 7913 1666 The data was expressed as Mean SE, n = 10 for each group; .sup.##P < 0.01, the model group was compared with the control group; *P < 0.05, the drug group was compared with the model group.

EXPERIMENTAL EXAMPLE 4

Effects of the Compounds of the Invention on Ethological Change in a Cuprizone Model in Mice

(74) Objective: neuroinflammation, pathological changes in white matter, and demyelination are the important pathogenesis for many central nervous system diseases. Cuprizone (dicyclohexanoneoxaly dihydrazone) can cause changes such as inflammation, demyelination, axonal injury, and cognitive function impairment. In this experiment, Y-maze and open-field behavior test were used to study the effects of the compounds of the invention on memory function and motion in a Cuprizone mouse model.

(75) Methods: SPF grade inbred C57BL/6 male mice, weighed (202) g, were randomly divided into a control group, a model group, and drug groups. The mice were adapted to the rearing environment for 3 days. Then, the control group was fed with a normal feed, and the other groups were fed with a feed containing 0.2% Cuprizone for model establishment. During model establishment, the mice in each group were intragastrically administered with a corresponding dose of drug, and were reared for 5 weeks. The mice were then subjected to the Y-maze and open field behavior test, wherein the number of arm entries in Y-maze was used to reflect the motion of mice; the spontaneous alternation in Y maze was used to reflect the working memory of mice; and the spontaneous activity in open-field behavior test was used to reflect the motion of mice.

(76) Results: the result of Y-maze test showed that as compared with the control group, Cuprizone model mice had an increase in the number of arm entries, and a reduction in the spontaneous alternation; the intragastrical administration of the compounds P6 and P5 of the invention could reduce the number of arm entries (FIG. 6), and enhance the spontaneous alternation (FIG. 7) in the model mice. The result of open-field test showed that as compared with the control group, Cuprizone model mice had a longer total distance of spontaneous activity; the intragastrical administration of the compounds P6 and P5 of the invention could shorten the total distance of spontaneous activity in the model mice (FIG. 8). The result showed that the compounds of the invention could improve the cognitive function and motor behavior in Cuprizone model mice, and alleviate the high activity in model mice.

EXPERIMENTAL EXAMPLE 5

Effect of the Compounds of the Invention on Demyelination in a Cuprizone Mouse Model

(77) Objectiv: pathological changes in white matter and demyelination are the important pathogenesis for many central nervous system diseases and mental disorders. Cuprizone can cause demyelination and pathological changes in white matter. Myelin basic protein (MBP) is a marker protein for myelination of axons, and is the main component of myelin sheath. In this experiment, Western Blot method was used to study the effects of the compounds of the invention on the MBP content and demyelination in the brain of Cuprizone model mice.

(78) Methods: Cuprizone mouse model establishment and administration method were the same as those described in Experimental example 4. After ethological tests were performed, the mice were anaesthetized by intraperitoneal injection of 10% chloral hydrate. The brains were harvested and stored at 80 C. Western blot assay: brain tissue was lysed with lysate to extract protein, and the protein concentration was determined. SDS-PAGE gel electrophoresis was performed, the protein was transferred onto a membrane, and the membrane was blocked. The protein was incubated with an anti-MBP antibody (a primary antibody) overnight at 4 C. in a refrigerator. After rinsing with TBST, it was incubated with a goat anti-mouse IgG antibody (a secondary antibody) at 4 C. in a refrigerator for 2 hrs. After washing the membrane with TBST, an ECL solution was added in a dark room, followed by tabletting, and exposure. Signal intensity for each protein band was analyzed using FluorChem 8900 gray-scale analysis software.

(79) Result: in the Western blot assay, the result showed that: as compared with the control group, the mice in the Cuprizone model group had the MBP content decreased significantly in frontal cortex; the compounds P5 and P4 of the invention could significantly enhance the MBP content in model mice, indicating that they could improve demyelination (FIG. 9).

(80) The result showed that the compounds of the invention could be used in the prevention and treatment of schizophrenia, depression and other mental disorders, as well as diseases such as cerebrovascular disease, demyelinating disease, multiple sclerosis, inflammatory demyelinating polyneuropathy, ischemic leukoencephalopathy, hypoxic leukoencephalopathy, and diabetic neuropathy.

EXPERIMENTAL EXAMPLE 6

Effects of the Compounds of the Invention on Microglial Cell Activation in a Cuprizone Mouse Model

(81) Objective: microglial activation and neuroinflammation are the important pathogenesis for many central nervous system diseases. Iba-1 could specifically label microglial cells. In this experiment, immunohistochemical method was used to study the effects of the compounds of the invention on Iba-1-labeled microglial cells in the brain of Cuprizone model mice.

(82) Methods: Cuprizone mouse model establishment and administration method were the same as those described in Experimental example 4. After ethological tests were performed, the mice were anaesthetized by intraperitoneal injection of 10% chloral hydrate. After perfusion, brain tissue was taken and fixed with 15% paraformaldehyde, and then frozen and sliced. Immunohistochemical staining: the frozen sections were inactivated with 3% H.sub.2O.sub.2 for 10 min and rinsed with PBS; the tissues were blocked with 10% serum and incubated at 37 C. for 1 h. Serum was washed off and a primary antibody (an anti-Iba-1 antibody) was added dropwise. The resultant mixture was kept at 4 C. overnight. After rinsing with PBST, a biotin-conjugated goat anti-rabbit IgG antibody (a secondary antibody) was added dropwise, and incubated at 37 C. for 2 hrs. After rinsing with PBST, a horseradish peroxidase-conjugated streptavidin (a third antibody) was added dropwise, and incubated at 37 C. for 2 hrs. After rinsing with PBS, DAB reagent was used to develop color, and the stained cells were transparent, and were mounted. Iba-1 positive cells were observed under microscope, and counted.

(83) Results: immunohistochemical staining result showed that as compared with the normal control group, the number of Iba-1-labeled microglial cells increased significantly in the brain of the Cuprizone model group, indicating that microglial cells were activated, and inflammation occurred; the compound P6 (25, 50 mg/kg) of the invention could significantly reduce the number of microglial cells, indicating that it could inhibit microglial cell activation, and alleviate inflammation (FIG. 10).

(84) The result showed that the compounds of the invention can be used in the prevention and treatment of a mental disorder such as schizophrenia and depression, and a nervous system disease such as neurodegenerative disease (e.g. Alzheimer's disease, Parkinson's disease), cerebrovascular disease, brain trauma, spinal cord injury, demyelinating disease, multiple sclerosis, or inflammatory demyelinating polyneuropathy.

(85) To sum up, the invention provides a class of novel compounds of Formula I, which can antagonize dopamine D2 receptor, and inhibit microglial activation and neuroinflammation; the animal experimental results showed that the compounds of the invention can reduce the hyperlocomotion in MK-801 model mice, and alleviate anxiety status; can improve memory dysfunction, abnormal motor behavior and hyperlocomotion in Cuprizone model mice, and inhibit microglial cell activation and demyelination in the model mice. These results showed that the compounds of the invention can be used in the prevention and treatment of various mental disorders and nervous system diseases.

(86) Although the embodiments of the invention have been described in detail, a person skilled in the art would understand that a variety of modifications and replacements, which are performed to the details according to all the disclosed teachings, all fall into the protection scope of the invention. The scope of the invention is defined by the attached claims and any equivalent thereof.