JPH06306079A - Novel tetracyclic compound - Google Patents

Abstract

PURPOSE:To provide the compound having a specific structure and useful as an immunosuppressive agent. CONSTITUTION:The objective compound of formula I (R<1> to R<4> are H, lower alkyl, trifluoromethyl, halogen, hydroxyl, lower alkoxyl, lower alkylthio, nitro, amino, lower alkylamino, lower alkanoylamino or lower alkoxycarbonyl; X is O or S). Optionally, the objective compound is obtained, e.g. by using a compound of formula II, etc., as a starting material, reacting it with an equivalent amount of oxalyl chloride and going through a compound of formula III (Et is ethyl), etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel tetracyclic compound useful as an immunosuppressant.

[0002]

BACKGROUND OF THE INVENTION Isochromano [4,3-b] quinoline-
A tetracyclic compound having a 7-carboxylic acid skeleton and an unsubstituted 3-position is known as an anti-inflammatory drug [Chem. Abstr., 115 , 183138m (1991)].

[0003]

An object of the present invention is to provide a novel tetracyclic compound having an excellent immunosuppressive action.

[0004]

According to the invention, the formula (I)

[0005]

[Chemical 2]

(In the formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents hydrogen, lower alkyl, trifluoromethyl, halogen, hydroxyl, lower alkoxyl, lower alkylthio, nitro, amino or lower alkylamino. ,
A novel tetracyclic compound represented by lower alkanoylamino or lower alkoxycarbonyl, and X represents oxygen or sulfur, or a pharmaceutically acceptable salt thereof.

In the definition of each group of formula (I), lower alkyl is linear or branched alkyl having 1 to 6 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl. , Tert-butyl, pentyl, neopentyl, hexyl and the like. Halogen represents each atom of fluorine, chlorine, bromine and iodine. The alkyl moiety of lower alkoxyl has the same definition as the above alkyl, and includes, for example, methoxy, ethoxy and the like. The alkyl part of lower alkylthio has the same definition as the above alkyl, and examples thereof include methylthio and ethylthio. The alkyl part of lower alkylamino has the same definition as the above alkyl, and examples thereof include methylamino and ethylamino. The alkyl moiety of lower alkanoylamino has the same definition as the above alkyl, and examples thereof include acetylamino and propanoylamino. The alkyl moiety of lower alkoxycarbonyl has the same definition as the above alkyl, and includes, for example, methoxycarbonyl, ethoxycarbonyl, tert-butoxycarbonyl and the like.

The pharmacologically acceptable salts of compound (I) include pharmacologically acceptable metal salts, ammonium salts, organic amine addition salts, amino acid addition salts and the like. Examples of the pharmacologically acceptable metal salt of compound (I) include alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as magnesium salt and calcium salt, aluminum salt, zinc salt, and ammonium salt. Is ammonium,
Examples thereof include salts such as tetramethylammonium, examples of pharmacologically acceptable organic amine addition salts include addition salts such as morpholine and piperidine, and examples of pharmacologically acceptable amino acid addition salts include addition salts such as lysine, glycine and phenylalanine. To be

Next, a method for producing the compound of the present invention will be described. Production Method 1 Compound (I) can be obtained according to the following reaction steps.

[0010]

[Chemical 3]

(Wherein R ¹ , R ² , R ³ , R ⁴ and X have the same meanings as defined above, Et represents ethyl and Ac represents acetyl).

Step 1: Compound (II) (manufactured by Aldrich) and an equivalent amount of oxalyl chloride were mixed with 2 equivalents of a Lewis acid such as aluminum trichloride in dichloromethane,
In a solvent inert to the reaction such as dichloroethane, usually at 0 ℃
~ Substituted biphenylcarboxylic acid chloride can be obtained by reacting at room temperature for 1 to 12 hours. Compound (III) can be obtained by treating this with a large excess of ethanol. Depending on the case,
It may be carried out in the presence of a base such as triethylamine or pyridine.

Step 2: Compound (IV) is reacted with an equivalent amount of N-bromosuccinimide in the presence of a catalyst in benzene or carbon tetrachloride at usually 70 to 80 ° C. for 1 to 4 hours. Can be obtained. Examples of the catalyst include radical initiators such as benzoyl peroxide or 2,2′-azobisisobutyronitrile.

Step 3: The compound (IV) is reacted with an equivalent amount of ethyl glycolate or ethyl thioglycolate in the presence of a base in a solvent such as tetrahydrofuran or dioxane at 0 ° C. to room temperature for 1 to 12 hours. The compound (V) can be obtained by As a base,
Examples thereof include sodium hydride and n-butyllithium.

Step 4: Compound (VI) is reacted at a room temperature to 100 ° C. for 1 to 12 hours in a mixed solvent of dioxane and water under alkaline conditions such as sodium hydroxide and potassium hydroxide. Can be obtained.

Step 5: Compound (VI) in the presence of 2 to 4 equivalents of potassium acetate in acetic anhydride, usually at 100 to 140 ° C.
Compound (VII) can be obtained by treating the above with 1 to 6 hours.

Step 6: Compound (VII) and an equivalent amount of compound (V
III) (manufactured by Aldrich Co.) and ethanol under alkaline conditions such as potassium hydroxide and sodium hydroxide.
Compound (I) can be obtained by reacting in a mixed solvent of water, dioxane-ethanol-water or the like, usually at room temperature to 100 ° C for 1 to 24 hours.

Production Method 2 Compound (Ia) wherein X is sulfur in Compound (I)
Alternatively, it can be obtained in the next reaction step.

[0019]

[Chemical 4]

(Wherein R ¹ , R ² , R ³ and R ⁴ have the same meanings as described above)

Step 7: Compound (II) and an equivalent amount of acetyl chloride or acetic anhydride in the presence of 2 equivalents of a Lewis acid such as aluminum trichloride in a solvent inert to the reaction such as dichloromethane and dichloroethane, usually at 0 ° C. ~ 1 at room temperature
Compound (IX) can be obtained by reacting for 12 hours.

Step 8: Compound (X) can be obtained by reacting compound (IX) with 2 equivalents of cupric bromide in ethyl acetate at usually 50 to 80 ° C. for 1 to 8 hours.

Step 9: Compound (XI) is reacted with an equivalent amount of N-bromosuccinimide in the presence of a catalyst in benzene or carbon tetrachloride at usually 70 to 80 ° C. for 1 to 4 hours. Can be obtained. Examples of the catalyst include radical initiators such as benzoyl peroxide or 2,2′-azobisisobutyronitrile.

Step 10: Compound (XI) and 2 to 5 equivalents of sodium hydrosulfide in a reaction-inert solvent such as N, N-dimethylformamide or tetrahydrofuran,
Compound (XII) can be usually obtained by reacting at 0 ° C to room temperature for 1 to 24 hours.

Step 11: Compound (XII) and an equivalent amount of compound (VIII) are mixed under an alkaline condition with potassium hydroxide, sodium hydroxide or the like, ethanol-water, dioxane-.
In a mixed solvent such as ethanol-water, usually at room temperature to 100 ° C
The compound (I-
a) can be obtained.

The intermediates and target compounds in the above-mentioned production method are isolated and purified by purification methods commonly used in synthetic organic chemistry such as filtration, extraction, washing, drying, concentration, recrystallization and various chromatographies. can do. In addition, the intermediate may be subjected to the next reaction without being particularly purified.

When it is desired to obtain the salt of compound (I), when compound (I) is obtained in the form of a salt, it may be purified as it is. When it is obtained in a free form, a suitable solvent is used. It may be dissolved or suspended in and the base may be added to form a salt.

The compound (I) and its pharmacologically acceptable salt may exist in the form of an adduct with water or various solvents, and these adducts are also included in the present invention. Specific examples of compound (I) obtained by each production method are shown in Table 1.

[0029]

[Table 1]

Next, the pharmacological action of compound (I) will be described with reference to test examples. Test Example 1 Inhibitory action of hemolytic plaque forming cells (PFC) Jane et al. [Science, 140 , 40
5 (1963)] Yamamoto et al. [Drugs Exp. Clin. Res.
(Drugs Experimental Clinical Research), III (1), 5 (1982)]] was added to improve.
That is, Balb / c male mice (7 weeks old) (Charles River) were sensitized with 1 × 10 ⁸ sheep red blood cells (Biotest Laboratories) by tail vein administration, and spleens were excised 6 to 7 days later. Next, the extracted spleen was crushed in hank's solution (Nissui Pharmaceutical Co., Ltd.) to give a cell suspension, filtered, and then centrifuged at 1200 rpm for 5 minutes. After centrifugation, the supernatant was discarded, treated with a Tris.NH ₄ Cl solution to remove red blood cells, and washed 3 times with hanks' solution. After discarding the supernatant, the cells were mixed with 10% fetal bovine serum (Gibco), streptomycin (Meiji Seika) 50 μg / m 2.
RPMI containing 50 μU / ml of penicillin (Meiji Seika) and 2-mercaptoethanol (5 × 10 ⁻⁵ M)
The cells were suspended in 1640 medium (Nissui Pharmaceutical). Next, in each well of the microculture plate (Nunc, 24 wells), the number of viable cells per hole is 1 × 10 ⁷ , and sheep red blood cells 5 × 10.
^Six compounds and a test compound (10 ^-2 M) dissolved in dimethyl sulfoxide were diluted with the above-mentioned RPMI-1640 medium to 10 ^-6 M, and the total volume was adjusted to 2 ml.
It was cultured at 7 ° C for 5 days.

After the completion of the culture, the cells were centrifuged at 2000 rpm for 5 minutes, the supernatant was removed, and the cells were suspended in 1 ml of Hanks 'liquid, centrifuged again, and suspended in 1 ml of Hanks' liquid. 50 μl of this suspension was preheated to 50 ° C. and 0.25% agarose.
Add 400 μl of hanks' solution together with 50 μl of sheep red blood cells, spread on a slide glass, put on a plaque assay plate, and react with guinea pig complement (Sedalen Laboratory) diluted 40-fold with phosphate buffer at 37 ° C. for 1-2 hours. , The number of direct hemolytic plaque cells that appear (Direct PF
The C number) was measured.

The inhibition rate of antibody production by the test compound was determined by the following formula.

[0033]

[Equation 1]

The control PFC number is a value in the absence of a test compound (dimethyl sulfoxide alone). The results are shown in Table 2.

[0035]

[Table 2]

The compound (I) or a pharmacologically acceptable salt thereof can be used as it is or in various pharmaceutical forms depending on its pharmacological action for the purpose of administration. The pharmaceutical composition of the present invention can be produced by uniformly mixing, as an active ingredient, an effective amount of compound (I) or a pharmaceutically acceptable salt thereof with a pharmaceutically acceptable carrier. The carrier may take a wide variety of forms depending on the form of preparation desired for administration. These pharmaceutical compositions are preferably in unit dose form suitable for oral or injection administration.

In preparing the composition in the oral dosage form, any useful pharmacologically acceptable carrier can be used. Oral liquid preparations such as suspensions and syrups include water, sugars such as sucrose, sorbitol, fructose, glycols such as polyethylene glycol, propylene glycol, sesame oil, olive oil,
It can be produced by using oils such as soybean oil, preservatives such as alkyl p-hydroxybenzoate, flavors such as strawberry flavor and peppermint. Powders, pills, capsules and tablets include excipients such as lactose, glucose, sucrose, mannitol,
Using starch, disintegrators such as sodium alginate, lubricants such as magnesium stearate and talc, binders such as polyvinyl alcohol, hydroxypropyl cellulose, gelatin, surfactants such as fatty acid esters, plasticizers such as glycerin, etc. Can be manufactured. Tablets and capsules are the most useful oral unit dosages because they are easy to administer. Solid pharmaceutical carriers are used in the production of tablets and capsules.

Injectable solutions can also be prepared using carriers which consist of distilled water, salt solutions, glucose solutions or mixtures of saline and glucose solutions. Compound (I)
Alternatively, the pharmacologically acceptable salt thereof can be administered orally or parenterally by injection, and its effective dose and the number of administrations vary depending on the administration form, age, body weight, symptoms of the patient, etc. 1 to 50 mg / kg per day from 3 to
It is preferable to administer in four divided doses.

The following are examples, reference examples and formulation examples.

[0040]

【Example】

Example 1: 9-Fluoro-3-phenylisothiochromano [4,3-b] quinoline-7-carboxylic acid (compound
1)

To 673 mg (4.05 mmol) of 5-fluoroisatin (manufactured by Aldrich) was added 4 ml of water containing 1.32 g (20.2 mmol) of potassium hydroxide,
To this was added 970 mg (4.04 mmol) of the compound (d) obtained in Reference Example 4 dissolved in 4 ml of ethanol. After heating under reflux for 13 hours, the solvent was evaporated under reduced pressure, ether-water was added to the residue, and the aqueous layer was washed with ether. The aqueous layer was filtered through Celite, hydrochloric acid was added to the filtrate, and the precipitated crystals were collected by filtration. After washing the obtained crystals with water and drying,
Recrystallized from dimethylformamide-water to give the title compound 5
80 mg (yield: 37%) was obtained.

NMR (DMSO-d ₆ ) δ (ppm):
8.46 (1H, d, J = 8Hz), 8.23-8.18 (1H, m), 7.85-7.43 (9H, m),
4.21 (2H, s) MS (m / e): 387 (M ⁺ )

IR (KBr) cm ^-1 : 1718,1626,1494,1
420,1326,1210,1191 Elemental analysis _{(%): C 23 H 14} FNO 2 S · 0.9C 3 H 7 NO Calculated: C68.11, H4.51, N5.87 Found: C68.10, H4. 37, N5.71 Melting point: 275.5-277.0 ℃

Example 2: 9-Fluoro-3- (2-fluorophenyl) isothiochromano [4,3-b] quinoline-7-carboxylic acid (Compound 2)

5-fluoroisatin 642 mg (3.8
1.30 g (19.4 mm) of potassium hydroxide to 7 mmol)
4 ml of water containing ol) and 4 ml of ethanol.
1.0 g of the compound (g) obtained in Reference Example 7 dissolved in
(3.87 mmol) was added. After heating under reflux for 13 hours, the solvent was evaporated under reduced pressure, ether-water was added to the residue, and the aqueous layer was washed with ether. The aqueous layer was filtered through Celite, hydrochloric acid was added to the filtrate, and the precipitated crystals were collected by filtration. The crystals obtained were washed with water, dried and then recrystallized from dimethylformamide-water to give the title compound 1.33 g (yield: 85%).
Got

NMR (DMSO-d ₆ ) δ (ppm):
8.48 (1H, d, J = 8Hz), 8.24-8.18 (1H, m), 7.76-7.34 (8H, m),
4.20 (2H, s) MS (m / e): 405 (M ⁺ )

IR (KBr) cm ^-1 : 1707,1626,1499,1
281,1210,1179 Elemental analysis _{(%): C 23 H 13} F 2 NO 2 S · 0.2H 2 O Calculated: C67.54, H3.30, N3.42 Found: C67.65, H3.28, N3.40 Melting point: 254.5-255.5 ℃

Example 3: 9-Fluoro-3-phenylisochromano [4,3-b] quinoline-7-carboxylic acid (Compound 3)

5-fluoroisatin 375 mg (2.2
750 mg (11.3 m) of potassium hydroxide in 6 mmol)
(4 mol of water) was added, and to this was added 600 mg (2.26 mmol) of the compound (1) obtained in Reference Example 12 dissolved in 4 ml of dioxane-ethanol (2: 1). After heating under reflux for 4 hours, the solvent was evaporated under reduced pressure, ether-water was added to the residue, and the aqueous layer was washed with ether. The aqueous layer was filtered through Celite, acetic acid was added to the filtrate, and the precipitated crystals were collected by filtration. After washing the obtained crystals with water and drying,
Recrystallized from dimethylformamide-water to give the title compound 6
63 mg (yield: 79%) was obtained.

NMR (DMSO-d ₆ ) δ (ppm):
8.42 (1H, d, J = 8Hz), 8.18-8.12 (1H, m), 7.89-7.41 (9H, m),
5.52 (2H, s) MS (m / e): 371 (M ⁺ )

IR (KBr) cm ^-1 : 1710,1621,1353,1
238,1186 Elemental analysis _{(%): C 23 H 14} FNO 3 Calculated: C74.39, H3.80, N3.77 Found: C74.51, H3.73, N3.83 mp: 276.5-278.0 ℃

Example 4: 9-Fluoro-3- (2-fluorophenyl) isochromano [4,3-b] quinoline-
7-carboxylic acid (compound 4)

5-fluoroisatin 470 mg (2.8
2mmol) potassium hydroxide 930mg (14.0m
4 ml of water containing (mol) was added, and to this was added 800 mg (2.82 mmol) of the compound (q) obtained in Reference Example 17 dissolved in 4 ml of dioxane-ethanol (2: 1). After heating under reflux for 4 hours, the solvent was evaporated under reduced pressure, ether-water was added to the residue, and the aqueous layer was washed with ether. The aqueous layer was filtered through Celite, acetic acid was added to the filtrate, and the precipitated crystals were collected by filtration. After washing the obtained crystals with water and drying,
Recrystallized from dimethylformamide-water to give the title compound 7
01 mg (yield: 64%) was obtained.

NMR (DMSO-d ₆ ) δ (ppm):
8.43 (1H, d, J = 8Hz), 8.18-8.13 (1H, m), 7.76-7.34 (9H, m),
5.52 (2H, s) MS (m / e): 389 (M ⁺ )

IR (KBr) cm ^-1 : 1710,1627,1507,1
352,1236,1194 Elemental analysis _{(%): C 23 H 13} F 2 NO 3 Calculated: C70.95, H3.37, N3.60 Found: C70.87, H3.19, N3.67 melting point: 274.0 -275.0 ° C

Reference Example 1: 4-Acetyl-3-methylbiphenyl [Compound (a)] 12.7 g (95.2 mmol) of aluminum trichloride was suspended in 100 ml of 1,2-dichloroethane, and 4.4 ml of acetyl chloride ( 61.8 mmol) was added. 8.0 g of 3-methylbiphenyl (Aldrich)
(47.6 mmol) was added, and the mixture was stirred at room temperature for 1 hour.
The reaction solution was poured into hydrochloric acid containing ice, and the organic layer was washed with concentrated hydrochloric acid and then with saturated saline. The organic layer was dried over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (4% ethyl acetate-hexane) to give the title compound (a) 7.72 g (yield: 77%).
Got

NMR (CDCl ₃ ) δ (ppm): 7.75
(1H, d, J = 8Hz), 7.60-7.57 (2H, m), 7.45-7.35 (5H, m), 2.60
(3H, s), 2.58 (3H, s) MS (m / e): 210 (M ⁺ )

Reference Example 2: 4-Bromoacetyl-3-methylbiphenyl [Compound (b)] 18.25 g (86.9) of the compound (a) obtained in Reference Example 1
(mmol) was dissolved in 200 ml of ethyl acetate, and 38.8 g (174 mmol) of cupric bromide was added. After heating under reflux for 6 hours, the reaction product was returned to room temperature and the insoluble material was filtered off.
The filtrate was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. Recrystallization from ethyl acetate-hexane gave 18.5 g (yield: 74%) of the title compound (b).

NMR (CDCl ₃ ) δ (ppm): 7.75
(1H, d, J = 8Hz), 7.61-7.57 (2H, m), 7.49-7.36 (5H, m), 4.43
(2H, s), 2.60 (3H, s) MS (m / e): 290,288 (M ⁺ ), 209

Reference Example 3: 4-Bromoacetyl-3-bromomethylbiphenyl [Compound (c)] 5.0 g (17.4 mm) of the compound (b) obtained in Reference Example 2
ol) in 150 ml of carbon tetrachloride, 4.0 g (22.5 mmol) of N-bromosuccinimide and 2,
5 mg of 2'-azobisisobutyronitrile was added, and the mixture was heated under reflux for 2 hours. The reaction product was returned to room temperature, the insoluble material was filtered off, the filtrate was washed with water and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure and recrystallized from chloroform-hexane to give the title compound (c) (4.5 g, yield: 71%).

NMR (CDCl ₃ ) δ (ppm): 7.83
(1H, d, J = 8Hz), 7.73 (1H, s), 7.54-7.39 (6H, m), 4.91 (2H,
s), 4.49 (2H, s) MS (m / e): 370,368,366 (M ⁺ ), 289,287,207

Reference Example 4: 7-phenylisothiochroman-4-one [compound (d)] 500 mg (1.37) of the compound (c) obtained in Reference Example 3
mmol) N, N-dimethylformamide 100 ml
Dissolved in water and stirred at 0 ° C with sodium hydrosulfide 330
mg (4.1 mmol) was added. After stirring at room temperature for 12 hours, the solvent was evaporated under reduced pressure, chloroform-water was added to the residue, the organic layer was washed with water, and dried over anhydrous magnesium sulfate.
The solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography (3% ethyl acetate-hexane), and recrystallized from hexane to give 127 mg of the title compound (d) (yield: 39
%) Was obtained.

NMR (CDCl ₃ ) δ (ppm): 8.16
(1H, d, J = 8Hz ), 7.63-7.42 (7H, m), 3.99 (2H, s), 3.59 (2H, s) MS (m / e): 240 (M +) IR (KBr) cm - ¹ : 1670, 1600, 1285 Melting point: 95.5-97.0 ° C

Reference Example 5: 4-Acetyl-2'-fluoro-3-methylbiphenyl [Compound (e)] 2'-Fluoro-3-methylbiphenyl synthesized by the method described in European Patent 184,384. Using 7.60 g, and in the same manner as in Reference Example 1, 7.03 g (yield: 76%) of the title compound (e) was obtained. NMR (CDCl ₃ ) δ (ppm): 7.78 (1H, d, J = 9Hz),
7.36-7.12 (7H, m), 2.61 (3H, s), 2.60 (3H, s) MS (m / e): 228 (M ⁺ )

Reference Example 6: 4-Bromoacetyl-2'-fluoro-3-methylbiphenyl [Compound (f)] Using Reference Example 2 using 7.53 g of the compound (e) obtained in Reference Example 5.
In the same manner as in 7.41 g of the title compound (f) (yield: 7
3%) was obtained.

NMR (CDCl ₃ ) δ (ppm): 7.77
(1H, d, J = 8Hz), 7.50-7.13 (7H, m), 4.45 (2H, s), 2.60 (3H, s) MS (m / e): 306,308 (M ⁺ )

Reference Example 7: 7- (2-Fluorophenyl)
Isothiochroman-4-one [Compound (g)] 4-bromoacetyl-2′-fluoro-3-bromomethyl was used in the same manner as in Reference Example 3 except that 4.00 g of the compound (f) obtained in Reference Example 6 was used. Biphenyl was obtained. The title compound (g) (1.23 g, yield: 37%) was obtained in the same manner as in Reference Example 4 without using any particular purification.

NMR (CDCl ₃ ) δ (ppm): 8.16
(1H, d, J = 8Hz ), 7.56-7.14 (6H, m), 3.98 (2H, s), 3.59 (2H, s) MS (m / e): 258 (M +) IR (KBr) cm - ¹ : 1673,1607,1470,1415,1387,128
0 Melting point: 87.0-88.0 ℃

Reference Example 8: Ethyl 2-methyl-4-phenylbenzoate [Compound (h)] 30 ml of carbon disulfide and 2.85 of oxalyl dichloride were added to 7.92 g (59.4 mmol) of aluminum trichloride.
ml (32.7 mmol) was added, followed by 5.0 g (29.7 mmol) of 3-methylbiphenyl. After stirring at room temperature for 6 hours, pour the reaction into hydrochloric acid containing ice,
Extracted with carbon disulfide. The organic layer was washed with concentrated hydrochloric acid, dried over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure, and 200 ml of ethanol was added. After stirring at room temperature for 12 hours, the solvent was evaporated under reduced pressure, ethyl acetate was added to the residue, the organic layer was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (1% ethyl acetate-hexane) to give the title compound (h) (7.12 g, yield: 68%).

NMR (CDCl ₃ ) δ (ppm): 8.00
(1H, d, J = 8Hz), 7.65-7.31 (7H, m), 4.38 (2H, q, J = 7Hz), 2.67
(3H, s), 1.43 (3H, t, J = 7Hz) MS (m / e): 240 (M ⁺ )

Reference Example 9: Ethyl 2-bromomethyl-4-phenylbenzoate [Compound (i)] 8.18 g (34.1 m) of the compound (h) obtained in Reference Example 8
mol) in 200 ml of carbon tetrachloride, 6.37 g (35.7 mmol) of N-bromosuccinimide and 5 mg of 2,2′-azobisisobutyronitrile were added,
The mixture was heated under reflux for 1 hour. The reaction product was returned to room temperature, the insoluble material was filtered off, the filtrate was washed with water and dried over anhydrous magnesium sulfate.
The solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography (1% ethyl acetate-hexane), and recrystallized from hexane to obtain 8.0 g of the title compound (i) (yield: 74%).

NMR (CDCl ₃ ) δ (ppm): 8.05
(1H, d, J = 8Hz), 7.68-7.40 (7H, m), 5.03 (2H, s), 4.43 (2H, q,
J = 7Hz), 1.44 (3H, t, J = 7Hz) MS (m / e): 320,318 (M ⁺ )

Reference Example 10: (2-Ethoxycarbonyl-
Ethyl 5-phenyl) benzyloxyacetate [Compound (j)] To 275 mg (6.24 mmol) of sodium hydride, 30 ml of anhydrous tetrahydrofuran was added, and 600 μl (6.24 mmol) of ethyl glycolate was added dropwise thereto. After stirring at room temperature for 30 minutes, 1.81 g (5.67 mmol) of the compound (i) obtained in Reference Example 9 was added. After stirring at room temperature for 12 hours, 5 ml of water was added to stop the reaction, and the solvent was distilled off under reduced pressure. Ethyl acetate was added to the residue, the organic layer was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure and purified by silica gel column chromatography (5% ethyl acetate-hexane),
1.43 g (yield: 74%) of the title compound (j) was obtained.

NMR (CDCl ₃ ) δ (ppm): 8.45
(1H, d, J = 8Hz), 7.98 (1H, s), 7.66-7.26 (6H, m), 5.11 (2H,
s), 4.36 (2H, q, J = 7Hz), 4.27-4.19 (4H, m), 1.40 (3H, t, J = 7H
z), 1.29 (3H, t, J = 7Hz) MS (m / e): 342 (M ⁺ )

Reference Example 11: (2-Carboxy-5-phenyl) benzyloxyacetic acid [Compound (k)] 1.37 g (4.0 m) of the compound (j) obtained in Reference Example 10
(mol) was dissolved in 50 ml of dioxane, 50 ml of 4N aqueous sodium hydroxide solution was added, and the mixture was heated under reflux for 2 hours. After the solvent was distilled off under reduced pressure, 100 ml of water was added and the mixture was washed with ether. Hydrochloric acid was added to the aqueous layer, and the precipitated crystals were collected by filtration, washed with water and dried. Recrystallization from chloroform gave 1.13 g (yield: quantitative) of the title compound (k).

NMR (DMSO-d ₆ ) δ ppm: 12.85
-12.84 (2H, m), 7.99-7.40 (8H, m), 4.97 (2H, s), 4.20 (2H, s) MS (m / e): 286 (M ⁺ )

Reference Example 12: 4-acetoxy-7-phenylisochromene [Compound (l)] 700 mg (2.4) of the compound (k) obtained in Reference Example 11
mmol) potassium acetate 960 mg (9.8 mmo)
20 ml of acetic anhydride containing 1) was added, and the mixture was heated under reflux for 3 hours. The solvent was evaporated under reduced pressure, ether-water was added to the residue, the organic layer was washed with an aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. After evaporating the solvent under reduced pressure, the residue was purified by silica gel column chromatography (2% ethyl acetate-hexane) and recrystallized from hexane.
515 mg (yield: 81%) of the title compound (l) was obtained.

NMR (CDCl ₃ ) δppm: 7.75-7.25
(7H, m), 7.03 (1H, d, J = 8Hz), 6.73 (1H, s), 5.16 (2H, s), 2.33
(3H, s) MS (m / e): 260 (M ⁺ ) IR (KBr) cm ^-1 : 1751,1644,1487,1372,1210 Melting point: 107.0-108.0 ° C

Reference Example 13: Ethyl 4- (2-fluorophenyl) -2-methylbenzoate [Compound (m)] 2'-Fluoro-3-synthesized by the method described in European Patent 184,384. Methylbiphenyl 1
Using 2.4 g and in the same manner as in Reference Example 8, 12.4 g (yield: 73%) of the title compound (m) was obtained.

NMR (CDCl ₃ ) δppm: 7.99 (1H,
d, J = 9Hz), 7.45-7.10 (6H, m), 4.37 (2H, q, J = 7Hz), 2.66 (3H,
s), 1.40 (3H, t, J = 7Hz) MS (m / e): 258 (M ⁺ )

Reference Example 14: 2-Bromomethyl-4- (2
-Fluorophenyl) ethyl benzoate [Compound (n)] Using 10.0 g of the compound (m) obtained in Reference Example 13,
In the same manner as in Reference Example 10, 10.4 g of the title compound (n)
(Yield: 79%) was obtained.

NMR (CDCl ₃ ) δppm: 8.05 (1H,
d, J = 8Hz), 7.65-7.14 (6H, m), 5.02 (2H, s), 4.44 (2H, q, J = 7H
z), 1.44 (3H, t, J = 7Hz) MS (m / e): 338,336 (M ⁺ )

Reference Example 15: [2-Ethoxycarbonyl-
5- (2-Fluorophenyl)] benzyloxyacetate [compound (o)] Using 7.00 g of the compound (n) obtained in Reference Example 14,
In the same manner as in Reference Example 10, the title compound (o) 4.50 g
(Yield: 60%) was obtained.

NMR (CDCl ₃ ) δppm: 8.04 (1H,
d, J = 8Hz), 7.92 (1H, s), 7.63-7.12 (5H, m), 5.11 (2H, s), 4.3
7 (2H, q, J = 7Hz), 4.22 (2H, q, J = 7Hz), 4.23 (2H, s), 1.40 (3H,
t, J = 7Hz), 1.28 (3H, t, J = 7Hz) MS (m / e): 360 (M ⁺ )

Reference Example 16: [2-carboxy-5- (2
-Fluorophenyl)] benzyloxyacetic acid [compound (p)] Using 2.42 g of the compound (o) obtained in Reference Example 15,
2.09 g of the title compound (p) in the same manner as in Reference Example 11.
(Yield: quantitative) was obtained.

NMR (DMSO-d ₆ ) δppm: 7.99
(1H, d, J = 8Hz), 7.84 (1H, s), 7.60-7.31 (5H, m), 4.97 (2H,
s), 4.19 (2H, s) MS (m / e): 304 (M ⁺ )

Reference Example 17: 4-acetoxy-7- (2-
Fluorophenyl) isochromene [compound (q)] Using 1.50 g of the compound (p) obtained in Reference Example 16,
In the same manner as in Reference Example 12, the title compound (q) 1.03 g
(Yield: 74%) was obtained.

NMR (CDCl ₃ ) δppm: 7.46-7.02
(7H, m), 6.74 (1H, s), 5.15 (2H, s), 2.33 (3H, s) MS (m / e): 284 (M ⁺ ) IR (KBr) cm ^-1 : 1758,1640, 1480,1200,1140 Melting point: 82.5-83.5 ℃

Formulation Example 1. Tablet A tablet having the following composition is prepared by a conventional method.

[0090]

[Table 3]

Formulation Example 2. Capsule A capsule having the following composition is prepared by a conventional method.

[0092]

[Table 4]

These are mixed and filled in a gelatin capsule. Formulation example 3. Injection preparation An injection preparation having the following composition is prepared by a conventional method.

[0094]

[Table 5]

Distilled water for injection is added to this to make a total volume of 5 ml (1 ampoule portion).

[0096]

INDUSTRIAL APPLICABILITY The present invention provides a novel tetracyclic compound useful as an immunosuppressant.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Tamura 3198-3 Ooka, Numazu City, Shizuoka Prefecture

Claims (1)

[Claims] 1. Formula (I): (In the formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents hydrogen, lower alkyl, trifluoromethyl, halogen, hydroxyl, lower alkoxyl, lower alkylthio, nitro, amino, lower alkylamino, lower alkanoyl. Represents amino or lower alkoxycarbonyl,
X represents oxygen or sulfur), and a novel tetracyclic compound represented by the formula: or a pharmaceutically acceptable salt thereof.