JPH06345695A - Production of lignans - Google Patents

Abstract

PURPOSE:To obtain the title compound which is useful for atherosclerosis efficiently in high position selectivity by reaction of a lactone with an unsaturated ketone in the presence of base followed by dehydration of the product. CONSTITUTION:In the presence of a base (preferably lithium bis(trimethylsilyl) amide, the reaction is effected between a lactone of formula I (R<2>, R<3> are lower alkoxy, alkylenedioxy; R<4> is lower alkoxy, H; R<5>, R<6> are lower alkyl) and an unsaturated ketone of formula II (R<1> is alkyl, cycloalkyl; R<7> is lower alkyl) and the product is dehydrated to give a compound of formula III. For example, the reaction of 3-(3,4-dimethoxy-phenyl)-4,5,6-tri-methoxy-1(3H)-isobenzofuranone with methyl (E)-4-cyclohexyl-4-oxo-2-butenoate give the objective compound.

Description

Detailed Description of the Invention

The present invention relates to a novel method for producing lignan analogs. More specifically, the present invention is a method for producing a lignan analog having an alkyl ketone chain, which is characterized by utilizing a regioselective Michael addition reaction, and an efficient method for producing a lignan analog, and a method for producing the same. It relates to a synthetic intermediate. The lignan analog produced by the method of the present invention is a compound useful for the treatment of arteriosclerosis, particularly atherosclerosis, and various compounds have been disclosed by the present applicant (JP-A-5-310634, WO93). / 0815
5).

The present invention has the formula (II):

[Chemical 6] [Wherein R ² and R ³ are independently a lower alkoxy group, or R ² and R ³ together form an alkylenedioxy group, and R ⁴ is a lower alkoxy group or hydrogen; ⁵ and R ⁶ are each independently a lower alkyl group] and a lactone compound represented by the formula (III):

[Chemical 7] [Wherein R ¹ is an alkyl group, a cycloalkyl group, a cycloalkyl lower alkyl group or an aralkyl group, and R ⁷ is a lower alkyl group], and the resulting compound is reacted with an unsaturated ketone compound. Formula by dehydration
(I):

[Chemical 8] The present invention provides a method for producing a compound represented by the formula: wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ have the same meanings as defined above. According to this method, the target compound can be produced in good yield. Therefore, the method of the present invention is suitable for large-scale synthesis.

An "alkyl group" in the definition of R ¹ is
It means a straight or branched C ₁ -C ₁₀ alkyl. Further, the "lower alkyl group" is a straight or branched chain C ₁
Means -C ₆ alkyl, methyl to, ethyl, n-
Examples include propyl, i-propyl, n-butyl, i-butyl, s-butyl, n-pentyl, 1-ethylpropyl, 2-ethylbutyl and the like. "Cycloalkyl group" means C
_It means _5- C ₇ cycloalkyl, and is exemplified by cyclopentyl, cyclohexyl and cycloheptyl. The “cycloalkyl lower alkyl group” means the above-defined lower alkyl group substituted with the above-defined cycloalkyl, and examples thereof include cyclohexylmethyl and cyclopentylethyl. The “aralkyl group” means the above lower alkyl substituted with aryl, and examples thereof include benzyl, p-methoxybenzyl, phenylethyl, phenylpropyl, and naphthylmethyl. The “lower alkoxy group” means oxo substituted with the above lower alkyl, and is exemplified by methoxy, ethoxy, propoxy and the like.

The term "alkylenedioxy" for R ² and R ³ means C ₁ -C ₃ alkylenedioxy and includes methylenedioxy, ethylenedioxy and propylenedioxy. In this production method, in particular, R ¹ is C ₁ -C ₆ alkyl, C ₅
-C ₇ cycloalkyl or a C ₅ -C ₇ cycloalkyl C ₁ -
It is suitable as a method for producing a compound (I) in which C ₆ alkyl, R ² , R ³ and R ⁴ are methoxy, and R ⁵ , R ⁶ and R ⁷ are methyl.

The manufacturing method of the present invention specifically comprises the following two steps:

[Chemical 9]

The first step is a step of synthesizing the compound (IV) by reacting the lactone compound (II) and the unsaturated ketone compound (III) in the presence of a base. The second step is a step in which the compound (IV) is treated with an acid for dehydration to synthesize the desired compound (I).

Reaction conditions The ratio of the compound (II) and the compound (III) used in the first step is not particularly limited, but usually the compound (II) is used.
I) is used in the same or excess amount with respect to compound (II), preferably 1: 1 to 1: 2. Examples of the base used include commonly used dialkyl metal amides, for example,
Lithium diisopropylamide, sodium dicyclohexylamide and the like, and also bis (trialkylsilyl) metal amides such as lithium bis (trimethylsilyl)
Amide, potassium bis (trimethylsilyl) amide, sodium bis (triethylsilyl) amide and the like can be used, and preferably lithium bis (trimethylsilyl)
Use an amide. The reaction solvent is, for example, ethers such as tetrahydrofuran, diethyl ether and dioxane, hydrocarbons such as n-hexane and n-pentane, aromatic hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as methylene chloride. , N, N-dimethylformamide, hexamethylphosphoric triamide and the like can be used alone or in combination. Preferred solvents are tetrahydrofuran, methylene chloride,
N, N-dimethylformamide and hexamethylphosphoric triamide. The reaction in this step is usually -10.
0 ° C to 100 ° C, preferably -80 ° C to room temperature,
It takes a few minutes to a few hours to complete.

As the acid used in the second step, an inorganic acid or an organic acid can be used. For example, hydrochloric acid, sulfuric acid, trifluoroacetic acid, sulfonic acids (methanesulfonic acid, p-toluenesulfonic acid, etc.), Lewis acid (trifluoride). Boron fluoride, titanium tetrachloride, etc.) can be used, and preferably boron trifluoride or methanesulfonic acid is used. The amount used is not particularly limited, but preferably 1 to 2 equivalents are used.
In addition, the compound (II) in which R ² = R ³ = R ⁴ = methoxy, R ⁵ = R ⁶ = methyl, and R ¹ = 2-ethylbutyl (CH ₂ CH
Compound (III) in which Et ₂ ) and R ⁷ = methyl is a novel compound. As the reaction solvent, aromatic hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as methylene chloride, and nitriles such as acetonitrile are used. This reaction is generally -70 ° C to 100 ° C, preferably -20
Complete in a few minutes to tens of hours at ℃ to room temperature.

The lactone compound (II) and the unsaturated ketone compound (III), which are the starting materials for the method of the present invention, can be produced from known compounds, for example, by the method described in the following reference examples. Hereinafter, the present invention will be described in more detail with reference to Examples and Reference Examples, but these are not intended to limit the present invention.

Synthesis Example of Compound (II) Reference Example 1 3- (3,4-dimethoxyphenyl) -4,5,6-trimethoxy-1 (3
H) -Isobenzofuranone: Synthesis step of II-1 1 ( Synthesis of 4,4-dimethyl-2- (3,4,5-trimethoxyphenyl) -2-oxazoline: 2) 2-amino-2-methyl -1-Propanol 386 g (4.34 mol)
In 1 l of dry methylene chloride under ice-cooling with 3,4,5-trimethoxybenzoyl chloride (Compound 1) 500 g (2.17 mo
l) of dry methylene chloride solution (1) is added dropwise over 2 hours. After the addition is complete, stir for an additional hour and filter the reaction with a glass filter. The filtrate is methylene chloride 5
Wash with 00 ml, combine the filtrate and washing solution and concentrate under reduced pressure. The residue is suspended in a mixed solvent of 900 ml of dry toluene and 100 ml of dry methylene chloride, and 206 ml (2.82 mmol) of thionyl chloride is added dropwise under ice cooling. After returning to room temperature, stir for another 30 minutes, ice-cool again, add 200 ml of water and aqueous sodium hydroxide solution (560 g of NaOH / 1.8 l of water) and extract with toluene. The extract is washed with water and saturated saline and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure was added to methylene chloride-n-hexane (200 ml-2.0
l) The desired oxazoline (compound
2) is obtained as 495 g of the first crystal and 61 g of the second crystal. Total yield 556 g
(96.5%, from compound 1). Melting point: 87-89 ° C ¹ H-NMR: δ (CDCl ₃ ) 1.39 (6H, s) 3.88 (3H, s) 3.91 (6
H, s) 4.10 (2H, s) 7.20 (2H, s).

Step 2 (Synthesis of Compound: II-1) 335 g (1.26 mol) of dry oxazoline (Compound 2) THF 1.7 cooled with a refrigerant at -35 to -40 ° C. under a nitrogen stream.
To the solution, add 800 ml (1.33 mol) of 1.66 N n-butyllithium-n-hexane solution dropwise over 1 hour and 15 minutes. After completion of the dropwise addition, the mixture was stirred at -20 to -35 ° C for an additional 1 hour, cooled to -78 ° C, and dried with 3,4-dimethoxybenzaldehyde 231 g (1.39 mol, 1.10 eq.) THF 500 ml.
The solution is added dropwise. After dropping, stir in an ice-water bath and stir for 1 hour, then add saturated aqueous ammonium chloride solution (400 ml) and water.
(400 ml), and extract with ethyl acetate. The extract,
Wash with water and saturated saline, and dry over anhydrous magnesium sulfate. Dissolve the residue concentrated under reduced pressure in 1.4 l of 10% sulfuric acid.
Heat to reflux for 0 minutes. Ice is added to the reaction solution, and the precipitated crystals are collected by filtration. The crystals collected by filtration are dissolved in 1.5 l of methylene chloride,
After washing with water, it is dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure is recrystallized from methylene chloride-methanol to obtain the desired lactone II-1 (390 g, 85.7%, from compound 2). Melting point: 141-142 ° C ¹ H-NMR: δ (CDCl ₃ ) 3.52 (3H, s) 3.83 (3H, s) 3.89 (3
H, s) 3.92 (3H, s) 3.95 (3H, s) 6.32 (1H, s) 6.72 (1H,
s) 6.86 (2H, s) 7.21 (1H, s).

The above reaction is represented by the following reaction formula.

[Chemical 10]

Reference Example 2 3- (3,4-dimethoxyphenyl) -5,6-methylenedioxy-1
Synthesis step of (3H) -isobenzofuranone: II-2 1 (2- (3,4-dimethoxy-α-hydroxybenzyl)-
4,5-Methylenedioxybenzaldehyde Synthesis of ethylenedioxyacetal: 4) i) 2-Bromo-4,5-methylenedioxybenzaldehyde (Compound 3) 28.0 g (122 mmol) of benzene in 250 ml of benzene, ethylene glycol Add 14 ml of p-toluenesulfonic acid (465 mg) and heat to reflux for 3 hours while dehydrating with a Dean-Stark tube. A saturated aqueous sodium hydrogen carbonate solution is added to the ice-cooled reaction solution, and the mixture is extracted with ethyl acetate.
The extract was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give 33.2 g of a crude acetal product as crystals. This product is used in the next reaction without purification. ii) Under a nitrogen stream, the obtained crude product of acetal 33.2
80 g (131 mmol) of 1.64 N n-butyllithium-n-hexane solution was added to 300 ml of dry THF in -78 ° C.
At that point. After stirring for another 30 minutes at the same temperature,
-Dimethoxybenzaldehyde 20.3 g (122 mmol)
Add 85 ml of dry THF solution and stir for another 30 minutes. A saturated aqueous ammonium chloride solution is added to the reaction solution, and the mixture is extracted with ethyl acetate. The extract is washed with water and saturated saline and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure was purified by medium pressure silica gel column chromatography (SiO ₂ ; 600
g, ethyl acetate-n-hexane = 1: 2 to 1: 1) to give the desired compound 4 as an oily substance in an amount of 35.6 g (80.9%,
(From compound 3). ¹ H-NMR: δ (CD ₃ OD) 3.77 (3H, s) 3.80 (3H, s) 3.90
~ 4.17 (4H, m) 5.91 (1H, d, J = 1.2Hz) 5.93 (1H,
d, J = 1.2Hz) 5.97 (1H, s) 6.13 (1H, s) 6.85 (1H, s)
s) 6.87 (1H, s) 6.88 (1H, s) 6.98 (1H, s) 7.02 (1
H, s).

Step 2 (2- (3,4-dimethoxy-α-acetoxybenzyl) -4,5-methylenedioxybenzaldehyde:
Synthesis of 5) i) The compound 4 (35.6 g, 98.3 mmo) under a nitrogen stream.
l), 360 mg of N, N-dimethylaminopyridine and 21 ml of triethylamine in 170 ml of dry THF under ice cooling,
Add 12.1 ml (128 mmol) of acetic anhydride and stir for 50 minutes while returning to room temperature. Add 4.4 ml of methanol and add 20
The reaction solution stirred for a minute is concentrated under reduced pressure, water is added to the residue, and the mixture is extracted with ethyl acetate. The extract was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give the desired crude acetate product as an oily substance.
You get 39.6 g. This product is used in the next reaction without purification. ii) The crude product of the acetate 39.6 g of acetone 3
Under ice-cooling, add 35 ml of 1 N hydrochloric acid to the 50 ml solution, and stir for 1 hour while returning to room temperature. The reaction mixture is neutralized with saturated aqueous sodium hydrogen carbonate solution, water is added to the residue concentrated under reduced pressure, and the mixture is extracted with ethyl acetate. The extract was washed with water and saturated saline and dried over anhydrous magnesium sulfate,
Concentration under reduced pressure gives 39.0 g of the desired crude product of aldehyde 5 as an oily substance. This product is used in the next reaction without purification. ¹ H-NMR: δ (CDCl ₃ ) 2.16 (3H, s) 3.85 (6H, s) 6.09
(2H, s) 6.80 to 6.89 (3H, m) 7.09
(1H, s) 7.32 (1H, s) 7.5
8 (1H, s).

Step 3 (Synthesis of Compound: II-2) 39.0 g of the crude product of aldehyde 5 was added to methanol 50
Dissolve it in a mixed solvent of 0 ml and 250 ml of dioxane, and add 130 ml of 2-methyl-2-butene. Next, a 250 ml aqueous solution of 44 g (486 mmol) of sodium chlorite and 57 g (365 mmol) of sodium dihydrogen phosphate dihydrate is added, and the mixture is stirred at room temperature for 20 minutes. To the reaction solution, add 160 ml of 5 N sodium hydroxide aqueous solution, stir for 25 minutes, and then add 6 N hydrochloric acid.
Add 160 ml and stir for another 20 minutes. Ice water is added to the reaction mixture, and the mixture is extracted with methylene chloride. The extract is washed with water, saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The crude crystals of the residue concentrated under reduced pressure were washed with ether and recrystallized from methanol to give 27.0 g (8%) of the desired lactone II-2 as crystals.
6.2%, from compound 4) Melting point: 176 to 178 ℃ ¹ H-NMR: δ (CDCl ₃ ) 3.83 (3H, s) 3.89 (3H, s) 6.12
(2H, ABtype, J = 1.2Hz) 6.20 (1H, s) 6.66 (2H, d,
J = 1.2 Hz) 6.86 (1H, s) 6.87 (1H, s) 7.25 (1H,
s).

The above reaction is represented by the following reaction scheme:

[Chemical 11]

The compound (III) can be produced by the following three methods. Synthesis Example of Compound (III) ( Method 1 ) Reference Example 3 Methyl (E) -4-cyclohexyl-4-oxo-2-butenoate: II
Ia Synthesis Step 1 (3-Cyclohexyl-5- (methoxycarbonyl) -2
-Isoxazoline: Synthesis of 8a) i) Hydroxylamine hydrochloride 154 g (2.20 mol)
And potassium carbonate 166 g (1.20 mol) in 800 ml aqueous solution, under ice cooling, cyclohexanecarboxaldehyde (compound 6a) 224 g (2.00 mol) 99% ethanol 133 ml
The solution is added dropwise. 1 hour after returning to room temperature after dropping
After stirring for 20 minutes, it is extracted with 900 ml of ethyl acetate. The extract is washed with water and a saturated saline solution to obtain a desired ethyl acetate solution of oxime. ii) Under ice cooling, about 10% sodium hypochlorite aqueous solution 3 l (about 4 mol) and triethylamine 28 ml (200 mm
ol), 220 ml (2.40 mol) of methyl acrylate are added dropwise to the mixture of oximes in ethyl acetate with vigorous stirring for 2 hours. After the addition is complete, stir for 1 hour while returning to room temperature and extract with ethyl acetate. The extract was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give the desired crude product of isoxazoline (Compound 8a) as an oily substance (369 g).
(88%, from compound 6a). ¹ H-NMR: δ (CDCl ₃ ) 1.10 to 1.45 (5H, m) 1.48 to 1.
90 (5H, m) 2.35 ~ 2.50 (1H, m) 3.19 (1H, d, J =
8.2 Hz) 3.20 (1H, d, J = 9.4 Hz) 3.79 (3H, s) 4.96
(1H, dd, J = 8.2 Hz, 9.4 Hz).

Step 2 (Synthesis of Compound III-a) i) Crude product of the above isoxazoline (Compound 8a) 3
Dissolve 69 g in a mixed solvent of 1.5 l of methanol, 316 ml of water and 474 ml of acetic acid, add 11.1 g of 10% palladium-carbon, and stir at room temperature for 6 hours in a hydrogen atmosphere. Palladium-carbon is filtered off, water is added to the residue concentrated under reduced pressure, and the mixture is extracted with ethyl acetate. The extract was washed with water, saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give the desired crude product of hydroxyketone as an oily substance (280 g). ii) 280 g of the above-mentioned hydroxyketone crude product and 819 ml (5.89 mol) of triethylamine in dry ethyl acetate 1.
Add 163 ml of methanesulfonyl chloride to the 4 l solution under ice cooling.
(2.10 mol) was added dropwise over 1 hour, and while returning to room temperature, 1
Stir for hours. Ice water is added to the reaction solution, which is further acidified by adding concentrated hydrochloric acid, and the mixture is extracted with ethyl acetate. The extract is washed with water, saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. 80 the residue concentrated under reduced pressure
158 g (62%, compound 8a) of the desired unsaturated ketoester III-a as crystals after crystallization from% hydrous methanol.
Get) Melting point: 53 to 56 ° C ¹ H-NMR: δ (CDCl ₃ ) 1.10 to 1.50 (5H, m) 1.60 to 2.
00 (5H, m) 2.50 ~ 2.63 (1H, m) 3.81 (3H, s) 6.69
(1H, d, J = 15.6 Hz) 7.17 (1H, d, J = 15.6 Hz).

Reference Example 4 Methyl (E) -6-ethyl-4-oxo-2-octenoate: III-b
Synthesis step 1 (3- (2-ethylbutyl) -5- (methoxycarbonyl)
2-Synthesis of 2-isoxazoline: 8b) i) 1-Bromo-2-ethylbutane (in 1-bromo-2-ethylbutane ( Compound 7b) 399g (2.42
650 ml of dry THF in (mol) is added dropwise over 2 hours. After the completion of dropping, the mixture was stirred for 1.5 hours while returning to room temperature, and then the reaction solution was cooled with ice, and 269 ml of 1-formylpiperidine (2.4 ml
2 mol) of dry THF in 450 ml is added dropwise. Furthermore, 1
After stirring for an hour, 202 g of hydroxylamine hydrochloride (2.
91 mol) aqueous solution (300 ml) was added, and the mixture was returned to room temperature.
Continue stirring for 1 hour and 20 minutes. The reaction solution is decanted, the residue is washed with ether, the organic layers are combined, and washed with water and saturated saline. After drying over anhydrous magnesium sulfate and concentration under reduced pressure, 362 g of the desired crude product of oxime is obtained as an oily substance. This product is used in the next reaction without purification. ii) About 10% sodium hypochlorite aqueous solution under ice cooling 2.
55 l (about 3.8 mol) and methyl acrylate 306 ml
A mixture of (3.39 mol) and 51 ml (363 mmol) of triethylamine in 850 ml of toluene was stirred vigorously with 362 g of the crude product of the oxime, 850 ml of toluene.
The solution is added dropwise. After the completion of dropping, the mixture is stirred for 2 hours while returning to room temperature, ice water is added to the reaction solution, and the mixture is extracted with ethyl acetate. The extract is washed with water, an aqueous sodium thiosulfate solution and saturated saline, and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure is distilled under reduced pressure to obtain the desired isoxazoline (compound 8b) as an oily substance (255 g, 49.5%, from compound 7b). Boiling point: 130-135 ℃ (5 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 0.88 (3H, t, J = 7.2 Hz) 0.89
(3H, t, J = 7.2 Hz) 1.27 ~ 1.61 (5H, m) 2.32 (2H,
d, J = 7.0 Hz) 3.21 (2H, d, J = 9.0 Hz) 3.79 (3H,
s) 4.99 (2H, d, J = 9.0 Hz).

Step 2 (Synthesis of Compound: III-b) The reaction is carried out in the same manner as in Step 2 of Reference Example 3 to obtain the desired unsaturated ketoester III-b from the above isoxazoline (Compound 8b). Boiling point: 85-90 ℃ (0.5 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 0.86 (6H, t, J = 7.2 Hz) 1.19
~ 1.50 (4H, m) 1.79 ~ 1.96 (1H, m) 2.54 (2H, d, J
= 6.6 Hz) 3.82 (3H, s) 6.67 (1H, d, J = 15.8 Hz)
7.09 (1H, d, J = 15.8 Hz).

Reference Example 5 (E) -5-Ethyl-4-oxo-2-heptenoate methyl: III-c
Synthetic Step 1 ( Synthesis of 3- (1-ethylpropyl) -5- (methoxycarbonyl) -2-isoxazoline: 8c) Reaction was carried out in the same manner as in Step 1 of Reference Example 3, (2-ethyl)
The desired isoxazoline (compound 8c) is obtained from butyraldehyde (compound 6c). Boiling point: 100-110 ℃ (2 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 0.88 (3H, t, J = 7.4 Hz) 0.89
(3H, t, J = 7.4 Hz) 1.33 ~ 1.71 (4H, m) 2.36 ~
2.53 (1H, m) 3.13 (1H, d, J = 9.6 Hz) 3.14 (1H, d,
J = 7.8 Hz) 3.79 (3H, s) 4.99 (1H, dd, J = 9.6 Hz,
7.8 Hz).

Step 2 (Synthesis of Compound: III-c) The reaction is performed in the same manner as in Step 2 of Reference Example 3 to obtain the desired unsaturated ketoester III-c from the above isoxazoline (Compound 8c). Boiling point: 68-72 ° C (0.8 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 0.86 (6H, t, J = 7.4 Hz) 1.42
~ 1.80 (4H, m) 2.51 ~ 2.70 (1H, m)
3.82 (3H, s) 6.72 (1H, d,
J = 15.8 Hz) 7.19 (1H,
d, J = 15.8 Hz).

Reference Example 6 Methyl (E) -5-methyl-4-oxo-2-hexenoate: III-d
Synthesis step 1 (5- (methoxycarbonyl) -3- (1-methylethyl))
Synthesis of 2-isoxazoline: 8d) The reaction is performed in the same manner as in Step 1 of Reference Example 3 to obtain the desired isoxazoline (compound 8d) from isobutyraldehyde (compound 6d). Boiling point: 84-88 ° C (1 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 1.19 (6H, d, J = 7.0 Hz) 2.65
~ 2.82 (1H, m) 3.23 (2H, d, J = 9.4 Hz) 3.80 (3H,
s) 4.99 (1H, t like, J = 9.4 Hz).

Step 2 (Synthesis of Compound: III-d) The reaction is performed in the same manner as in Step 2 of Reference Example 3 to obtain the desired unsaturated ketoester III-d from the above isoxazoline (Compound 8d). Boiling point: 76-80 ° C (6 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 1.16 (6H, d, J = 7.0 Hz) 2.76
~ 2.94 (1H, m) 3.82 (3H, s) 6.74 (1H, d, J = 15.8
Hz) 7.20 (1H, d, J = 15.8 Hz).

Each reaction of Reference Examples 3 to 6 is represented by the following reaction formula.

[Chemical 12]

Synthesis Example of Compound (III) ( Method 2 ) Reference Example 7 Methyl (E) -4-cyclohexyl-4-oxo-2-butenoate: II
Step 1 of synthesis of Ia ((±) -3-acetoxy-3- (methoxycarbonyl))
Synthesis of propionic acid: 10) A mixture of 201 g (1.50 mol) of DL-malic acid (Compound 9) and 750 ml of acetyl chloride was added at room temperature for 68 hours and then 50 times.
Stir at ℃ for 2 hours. To the reaction mixture residue concentrated under reduced pressure, add 300 ml of toluene and concentrate again under reduced pressure twice. Then, crystallize the acid anhydride using 100 ml of toluene. To the crystalline residue obtained by distilling off toluene under reduced pressure, add 1.50 l of methanol under ice cooling, stir at room temperature for 1 hour, and then leave for 15 hours. The reaction mixture residue concentrated under reduced pressure,
Add 300 ml of toluene and concentrate again under reduced pressure. The concentrated residue was crystallized using 150 ml of toluene and washed with petroleum ether to give the desired carboxylic acid (compound 10).
279 g (98%) are obtained as crystals. Melting point: ~ 63 ° C ¹ H-NMR: δ (CDCl ₃ ) 2.16 (3H, s), 2.96 (2H, d, J =
6.0 Hz), 3.78 (3H, s), 5.49 (1H, t, J = 6.0 Hz).

Step 2 (Synthesis of Compound III-a) i) 196 g (1.10 mol) of the carboxylic acid (Compound 10)
And 196 ml (1.65 mol) of thionyl chloride at 30 ° C.
Stir for 30 minutes and at 50 ° C for 1 hour. To the residue of the reaction solution concentrated under reduced pressure, 250 ml of toluene is added and concentrated again under reduced pressure. This operation is repeated twice to obtain the desired crude product of acid chloride. This product is used in the next reaction without purification. ii) under a nitrogen stream, to a suspension of the crude product of the acid chloride and 9.52 g (5.00 mmol) of cuprous iodide in 1 l of dry THF,
At 25 ° C, 1.17 l (1.19 mol) of 1.02 M cyclohexylmagnesium bromide-THF solution is added dropwise over 2 hours and 30 minutes. After dripping, stir for another 30 minutes and then 1.
Stop the reaction by adding 1 L of 3 N hydrochloric acid and ice. The reaction solution is extracted with ethyl acetate, and the extract is washed with saturated saline, saturated sodium hydrogen carbonate aqueous solution, sodium thiosulfate aqueous solution, and saturated saline. After drying over anhydrous magnesium sulfate, the product is concentrated under reduced pressure to obtain a desired crude product of the ketone.
This product is used in the next reaction without purification. iii) dry acetonitrile of the crude ketone 55
To the 0 ml solution, add 230 ml (1.65 mol) of triethylamine and heat to reflux for 1 hour. Add 1.3 N to the ice-cooled reaction mixture.
Add 1 l of hydrochloric acid and ice and extract with ethyl acetate. The extract is washed with saturated brine and dried over anhydrous magnesium sulfate. To the residue concentrated under reduced pressure, 1 l of petroleum ether was added for crystallization, and the obtained crystal was further recrystallized from methanol containing 85% water to obtain 76.8 g of the desired unsaturated ketoester III-a crystal. The crystal mother liquor and the recrystallized mother liquor are combined and distilled under reduced pressure, and then recrystallized from 85% hydrous methanol to obtain 32.5 g of the desired compound. Total yield 109 g (51%, from compound 10). Melting point: 56-57 ° C. ¹ H-NMR spectrum was in agreement with the spectrum of the compound obtained in Reference Example 3.

Reference Example 8 Methyl (E) -6-ethyl-4-oxo-2-octenoate: III-b
Reaction was carried out in the same manner as in Step 2 of Synthesis Reference Example 7 to give compound 10
(Step 1 of Reference Example 7) and the desired unsaturated ketoester III-b from (2-ethyl) butylmagnesium bromide
To get The physical properties of the compound obtained here completely agreed with those of the compound obtained in Reference Example 4.

Reference Example 9 Methyl (E) -5-ethyl-4-oxo-2-heptenoate: III-c
Reaction was carried out in the same manner as in Step 2 of Synthesis Reference Example 7 to give compound 10
(Step 1 of Reference Example 7) and the target unsaturated ketoester III-c from (1-ethyl) propylmagnesium bromide
To get The physical properties of the compound obtained here were completely in agreement with those of the compound obtained in Reference Example 5.

Reference Example 10 Synthesis of Methyl (E) -4-oxo-2-hexenoate: III-e The reaction was carried out in the same manner as in Step 2 of Reference Example 7 to give compound 10
The target unsaturated ketoester III-e is obtained from (Step 1 of Reference Example 7) and ethylmagnesium bromide. Boiling point: 87-90 ℃ (8 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 1.14 (3H, t, J = 7.2 Hz) 2.67
(2H, q, J = 7.2 Hz) 3.81 (3H, s) 6.69 (1H, d, J =
16.0 Hz) 7.09 (1H, d, J = 16.0 Hz).

The reactions described in Reference Examples 7 to 10 are represented by the following reaction formulas.

[Chemical 13]

Synthesis Example of Compound (III) ( Method 3 ) Reference Example 11 Methyl (E) -6-ethyl-4-oxo-2-octenoate: III-b
Synthesis Step 1 ( Synthesis of ((E) -3- (methoxycarbonyl) acryloyl chloride: 12)) i) Maleic anhydride 300 g (3.06 mol) in dry toluene 900 ml suspension, methanol 136 ml (3.37 mol)
And 3.0 ml of thionyl chloride are added, and the mixture is heated under reflux for 2 hours. The reaction solution is cooled with ice and the precipitated crystals are collected by filtration to obtain crude crystals of the target compound. This product was recrystallized from THF (500 ml) -isopropyl ether (1 l) to give a melting point of 145-146.
210 g (52.7%) of the desired monomethyl ester at ℃
obtain. ii) To a suspension of 97.5 g (750 mmol) of the monomethyl ester in 250 ml of dry benzene, 82.2 ml (1.
13 mol) and DMF 1.0 ml, and stir at 70 ℃ for 2.5 hours. The reaction mixture was concentrated under reduced pressure and the residue was distilled under reduced pressure to give the desired acid chloride (compound 12) as an oily substance.
You get 5.3 g (85.3%). Boiling point: 72-73 ° C (15 mmHg) ¹ H-NMR: δ (CDCl ₃ ) 3.86 (3H, s) 6.99 (1H, ABtype, J
= 15.4 Hz) 7.00 (1H, ABtype, J = 15.4 Hz).

Step 2 (Synthesis of Compound: III-b) Under a stream of nitrogen, 0.97 M (2-ethyl) butylmagnesium bromide-THF solution (860 ml, 837 mmol) was added under ice-cooling of 1.15.
728 ml (837 mmol) of M zinc chloride-THF solution is added dropwise over 55 minutes. After the dropping was completed, the mixture was stirred for another 50 minutes, then tetrakis (triphenylphosphine) palladium 14.8 g
(12.8 mmol) is added. Subsequently, a solution of 95.3 g (639 mmol) of the acid chloride (Compound 12) in 250 ml of dry THF is added dropwise over 1 hour and 50 minutes. After completion of dropping, the mixture is stirred for another 30 minutes, 3N hydrochloric acid (600 ml) is added, and the mixture is extracted with ethyl acetate. The extract is washed with water and saturated saline and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure is dissolved in 200 ml of a mixed solvent of ether-n-hexane (ether: n-hexane = 1: 4) and filtered through silica gel (350 g). After washing the silica gel with the above mixed solvent (1 l),
The filtrate and washings are combined and concentrated under reduced pressure. The residue is distilled under reduced pressure to obtain 67.6 g (53.4%) of the desired unsaturated ketoester III-b as an oily substance. The physical properties of the compound obtained here completely agreed with those of the compound obtained in Reference Example 4.

The reaction described in Reference Example 11 is represented by the following reaction formula.

[Chemical 14]

Next, a method for producing the compound (I) will be described. Example 1 3- (Cyclohexanecarbonyl) -1- (3,4-dimethoxyphen)
Nyl) -4-hydroxy-2- (methoxycarbonyl) -6,7,8-to
Limethoxynaphthalene: Synthesis step of I-1a 1 (3- (cyclohexanecarbonyl) -1- (3,4-dimethoxyphenyl) -1,2-dihydro-1,4-dihydroxy-2-
(Methoxycarbonyl) -6,7,8-trimethoxynaphthalene
: IV-1a synthesis) (TMS) ₂ NH 256 ml (1.15 mol) dry THF under nitrogen flow
700 ml (1.15 mol) of 1.64 M n-BuLi-n-hexane solution was added dropwise to the 1.15 l solution under ice cooling. Lactone II-1 (Reference Example) was added to the reaction solution cooled in a dry ice-acetone bath.
1) Add 207 g (575 mmol) of dry DMF 1.15 l solution dropwise over 1 hour. After stirring for another 45 minutes, unsaturated ketoester III-a (Reference Example 3) 134 g (684 mmol) of dry THF was added.
Add 456 ml solution dropwise over 45 minutes. After the dropping, stir for 15 minutes at the same temperature, raise the temperature to 0 ° C, and cool with ice.
Stir for hours. To the reaction solution, add 1.8 liter of 2N hydrochloric acid and extract with ethyl acetate. The extract is washed with water and saturated saline and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure is crystallized from 1 l of methanol to obtain 180 g of a target compound IV-1a as crude crystals. The crystals are recrystallized from methylene chloride-methanol to obtain 148 g of the target compound IV-1a. The concentrated recrystallized mother liquor was recrystallized twice to obtain 7.0 g of compound IV-
You get 1a. Total yield 155 g (49%, compound II-1 from) ^{mp:. 154 ~ 155 ℃ 1 H} -NMR: δ (CDCl 3) 0.90 ~ 1.83 (10H, m) 2.40 ~
2.58 (1H, m) 3.45 (3H, s) 3.67 (3H, s) 3.82 (3H, s)
s) 3.85 (3H, s) 3.93 (1H, s) 3.94 (3H, s) 3.99 (3
H, s) 5.75 (1H, s) 6.42 (1H, dd, J = 8.4 Hz, 2.4 H
z) 6.64 (1H, d, J = 8.4 Hz) 7.14 (1H, d, J = 2.4 H
z) 7.51 (1H, s).

[0036] Step 2 (Compound: I-1a Synthesis of) under a nitrogen atmosphere, in dry methylene chloride 750ml solution of the compound IV-1a 155 g (279 mmol ), under ice-cooling, BF ₃ · OEt ₂ 4
Add 3 ml of a solution of 4.8 ml (364 mmol) in dry methylene chloride 90 ml.
Drip in 0 minutes and stir for another 50 minutes at the same temperature. To the reaction solution, triethylamine 58.4 ml (420 mmol) was added,
Stir at room temperature for 30 minutes. Water is added to the residue concentrated under reduced pressure, and the mixture is extracted with ethyl acetate. 1N hydrochloric acid, water,
The extract is washed with saturated brine and dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure was crystallized from 500 ml of methanol, and the obtained crystals were further extracted from methylene chloride-methanol.
Recrystallize twice to obtain 140 g of the target compound I-1a.
(93%) get it. Melting point: 150 to 151 ° C ¹ H-NMR: δ (CDCl ₃ ) 1.15 to 1.90 (10H, m) 2.70 to
2.90 (1H, m) 3.24 (3H, s) 3.44 (3H, s) 3.86 (3H,
s) 3.89 (3H, s) 3.93 (3H, s) 4.03 (3H, s) 6.81 ~
6.87 (3H, m) 7.71 (1H, s) 13.99 (1H, s). IR: υ (Nujol) 1714, 1606, 1580, 1516, 1489, 1410,
1240, 1197, 1142, 1107, 1063, 1027, 1004 cm ^-1 . Elemental analysis (C ₃₀ H ₃₄ O ₉ ): Calculated value; C 66.90%, H 6.36% Measured value; C 66.92%, H 6.39%.

Example 2 1- (3,4-dimethoxyphenyl) -3- (3-ethyl-1-oxope
) -Hydroxy-2- (methoxycarbonyl) -6,7,8-
Trimethoxynaphthalene: Step of synthesizing I-1b 1 (1- (3,4-dimethoxyphenyl) -3- (3-ethyl-1-
Oxopentyl) -1,2-dihydro-1,4-dihydroxy-2-
(Methoxycarbonyl) -6,7,8-trimethoxynaphthalene
: Synthesis of IV-1b) 1.0 M LiN (TMS) ₂ -THF solution 1 l (1.0 mo
l, 2.0 eq.), a solution of 180 g (0.50 mol) of lactone II-1 (reference example 1) in dry methylene chloride (500 ml) at -78 ° C is added dropwise over 1 hour. After stirring for an additional 40 minutes, the unsaturated ketoester III-b (Reference Example 4) 109 g (0.5
Add a solution of 5 mol, 1.1 eq.) In 300 ml of dry THF dropwise over 40 minutes. After the dropping, raise the temperature to 0 ° C and cool with ice.
Ice and 2 N hydrochloric acid (1 l) are added to the reaction mixture which is stirred for 3 hours, and the mixture is extracted with ethyl acetate. The extract is washed with water and saturated saline and then dried over anhydrous magnesium sulfate. The residue concentrated under reduced pressure is crystallized from 700 ml of methanol, and the obtained crystal is recrystallized twice from 600 ml of methanol to obtain 194 g (70%) of the desired compound IV-1b. Melting point: 132-133 ° C ¹ H-NMR: δ (CDCl ₃ ) 0.65 (3H, t, J = 7.2Hz) 0.69 (3
H, t, J = 7.2Hz) 0.80 ~ 1.29 (5H, m) 2.03 (1H, d
d, J = 14.0 Hz, 7.0 Hz) 2.31 (1H, dd, J = 14.0 Hz,
6.4 Hz) 3.40 (3H, s) 3.67 (3H, s) 3.81 (3H, s) 3.
86 (3H, s) 3.88 (1H, s) 3.94 (3H, s) 3.99 (3H, s)
5.73 (1H, s) 6.43 (1H, dd, J = 8.4 Hz, 2.2 Hz) 6.6
4 (1H, d, J = 8.4 Hz) 7.14 (1H, d, J = 2.2 Hz) 7.5
4 (1H, s).

Step 2 (Synthesis of Compound: I-1b) The reaction is carried out in the same manner as in Step 2 of Example 1 to obtain the desired compound I-1b from the compound IV-1b. Melting point: 128.5 to 129.5 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.83 (6H, t, J = 7 Hz) 1.20 to
1.42 (4H, m) 1.96 ~ 2.12 (1H, m) 2.73 (2H, d, J =
6Hz) 3.25 (3H, s) 3.44 (3H, s) 3.86 (3H, s) 3.89 (3
H, s) 3.93 (3H, s) 4.04 (3H, s) 6.78 ~ 6.90 (3H,
m) 7.73 (1H, s) 14.38 (1H, s) IR: υ (CHCl ₃ ) 2968, 1729, 1606, 1576, 1514, 1489,
1464, 1412, 1139, 1064, 1028 cm ^-1 Elemental analysis (C ₃₀ H ₃₆ O ₉ ): Calculated value; C 66.65%, H 6.71% Measured value; C 66.72%, H 6.69%.

Example 3 1- (3,4-dimethoxyphenyl) -3- (2-ethyl-1-oxobutane
Tyl) -4-hydroxy-2- (methoxycarbonyl) -6,7,8-to
Limethoxynaphthalene: Synthesis step of I-1c 1 (1- (3,4-dimethoxyphenyl) -3- (2-ethyl-1-
Oxobutyl) -1,2-dihydro-1,4-dihydroxy-2- (methoxycarbonyl) -6,7,8-trimethoxynaphthalene: I
Synthesis of V-1c) Reaction was carried out in the same manner as in Step 1 of Example 1 to give lactone I
The target compound IV-1c is obtained from I-1 (Reference Example 1) and unsaturated ketoester III-c (Reference Example 5). Melting point: 154.5 to 156 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.19 (3H, t, J = 7.4 Hz) 0.75
(3H, t, J = 7.4 Hz) 1.13 to 1.72 (4H, m) 2.35 to 2.
51 (1H, m) 3.42 (3H, s) 3.65 (3H, s) 3.79 (3H, s)
3.86 (3H, s) 3.94 (3H, s) 3.96 (1H, s) 3.99 (3H, s)
s) 5.76 (1H, s) 6.42 (1H, dd, J = 8.4 Hz, 2.2 Hz)
6.64 (1H, d, J = 8.4 Hz) 7.14 (1H, d, J = 2.2 Hz)
7.56 (1H, s).

Step 2 (Synthesis of Compound: I-1c) The reaction is carried out in the same manner as in Step 2 of Example 1 to obtain the desired compound I-1c from the compound IV-1c. Melting point: 113-115 ° C (acetone-n-hexane) ¹ H-NMR: δ (CDCl ₃ ) 0.82 (3H, t, J = 8 Hz) 0.83 (3
H, t, J = 8 Hz) 1.42 to 1.60 (2H, m) 1.64 to 1.81
(2H, m) 2.78 to 2.90 (1H, m) 3.24 (3H, s) 3.42 (3
H, s) 3.86 (3H, s) 3.89 (3H, s) 3.93 (3H, s) 4.03
(3H, s) 6.81 ~ 6.87 (3H, m) 7.72 (1H, s) 14.18 (1
H, s) IR: υ (CHCl ₃ ) 1730, 1606, 1575, 1523, 1490, 1463,
1412, 1137, 1062, 1029 cm ^-1 Elemental analysis (C ₂₉ H ₃₄ O ₉ ): Calculated C 66.14%, H 6.51%; Measured C 66.09%, H 6.64%.

Example 4 1- (3,4-dimethoxyphenyl) -4-hydroxy-2- (meth)
Cycarbonyl) -3- (2-methyl-1-oxopropyl) -6,7,8-
Trimethoxynaphthalene: Synthetic Step of I-1d 1 (1- (3,4-dimethoxyphenyl) -1,2-dihydro-
1,4-dihydroxy-2- (methoxycarbonyl) -3- (2-methyl-1-oxopropyl) -6,7,8-trimethoxynaphthalene
: Synthesis of IV-1d) Reaction was performed in the same manner as in Step 1 of Example 1 to give lactone I
The target compound IV-1d is obtained from I-1 (Reference Example 1) and unsaturated ketoester III-d (Reference Example 6). Melting point: 155 to 156 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.67 (3H, d, J = 7.0 Hz) 1.04
(3H, d, J = 6.8 Hz) 2.73 to 2.88 (1H, m) 3.43 (3H,
s) 3.67 (3H, s) 3.81 (3H, s) 3.86 (3H, s) 3.91 (1
H, s) 3.94 (3H, s) 3.99 (3H, s) 5.74 (1H, s) 6.44
(1H, dd, J = 8.4 Hz, 2.0 Hz) 6.65 (1H, d, J = 8.4
Hz) 7.14 (1H, d, J = 2.0 Hz) 7.52 (1H, s).

Step 2 (Synthesis of Compound: I-1d) The reaction is performed in the same manner as in Step 2 of Example 1 to obtain the desired compound I-1d from the compound IV-1d. Melting point: 108-110 ° C (90% water-containing methanol) ¹ H-NMR: δ (CDCl ₃ ) 1.15 (3H, d, J = 7 Hz) 1.16 (3
H, d, J = 7 Hz) 3.09 to 3.20 (1H, m) 3.24 (3H, s)
3.43 (3H, s) 3.86 (3H, s) 3.89 (3H, s) 3.93 (3H, s)
4.03 (3H, s) 6.79 to 6.90 (3H, m) 7.71 (1H, s) 1
3.76 (1H, s) IR: υ (nujol) 1724, 1604, 1579, 1510,
1410, 1195, 1133, 1104, 1024, 988, 959, 843 cm ^-1 Elemental analysis (C ₂₇ H ₃₀ O ₉ ): Calculated value; C 65.05%, H 6.07% Measured value; C 65.16%, H 6.08%.

Example 5 1- (3,4-dimethoxyphenyl) -4-hydroxy-2- (meth)
Cycarbonyl) -3- (1-oxopropyl) -6,7,8-trimetho
Xinaphthalene: Synthesis step of I-1e 1 (1- (3,4-dimethoxyphenyl) -1,2-dihydro-
(Synthesis of 1,4-dihydroxy-2- (methoxycarbonyl) -3- (1-oxopropyl) -6,7,8-trimethoxynaphthalene: IV-1e) The reaction is carried out in the same manner as in Step 1 of Example 2. , Lactone I
The target compound IV-1e is obtained from I-1 (Reference Example 1) and unsaturated ketoester III-e (Reference Example 10). Melting point: 143-145 ° C (methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.89 (3H, t, J = 7.4 Hz) 2.31
(2H, q, J = 7.4 Hz) 3.41 (3H, s) 3.68 (3H, s) 3.82
(3H, s) 3.86 (3H, s) 3.87 (1H, s) 3.94 (3H, s) 3.
99 (3H, s) 5.73 (1H, s) 6.44 (1H, dd, J = 8.4 Hz,
2.2 Hz) 6.65 (1H, d, J = 8.4 Hz) 7.12 (1H, d, J =
2.2 Hz) 7.51 (1H, s).

Step 2 (Synthesis of Compound: I-1e) The reaction is carried out in the same manner as in Step 2 of Example 1
The target compound I-1e is obtained from IV-1e. Melting point: 145 to 146 ° C (ethyl acetate-diisopropyl ether) ¹ H-NMR: δ (CDCl ₃ ) 1.18 (3H, t, J = 7.2 Hz) 2.81
~ 2.91 (2H, m) 3.25 (3H, s) 3.45 (3H, s) 3.86 (3H,
s) 3.89 (3H, s) 3.93 (3H, s) 4.03 (3H, s) 6.80 ~
6.85 (3H, m) 7.74 (1H, s) 14.60 (1H, s) IR: υ (nujol) 1730, 1604, 1577, 1202, 1117, 1023
cm ^-1 Elemental analysis (C ₂₆ H ₂₈ O ₉ ): Calculated value; C 64.46%, H 5.83% Measured value; C 64.53%, H 5.80%.

Example 6 3- (Cyclohexanecarbonyl) -1- (3,4-dimethoxyphen)
Nyl) -4-hydroxy-2- (methoxycarbonyl) -6,7-methyl
Dioxynaphthalene: Synthesis step of I-2a 1 (3- (cyclohexanecarbonyl) -1- (3,4-dimethoxyphenyl) -1,2-dihydro-1,4-dihydroxy-2-
(Methoxycarbonyl) -6,7-methylenedioxynaphthalene: Synthesis of IV-2a) Reaction was carried out in the same manner as in Step 1 of Example 1 to give lactone I
The target compound IV-2a is obtained from I-2 (Reference Example 2) and unsaturated ketoester III-a (Reference Example 3). Melting point: 193-195 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.90-1.88 (10H, m) 2.39-
2.57 (1H, m) 3.65 (3H, s) 3.80 (3H, s) 3.82 (3H,
s) 4.02 (1H, s) 4.96 (1H, br. s) 6.07 (2H, s) 6.33
(1H, dd, J = 8.4 Hz, 2.2 Hz) 6.62 (1H, d, J = 8.4
Hz) 6.98 (1H, d, J = 2.2 Hz) 7.20 (1H, s) 7.45 (1
H, s).

Step 2 (Synthesis of Compound: I-2a) The reaction is carried out in the same manner as in Step 2 of Example 1
The target compound I-2a is obtained from IV-2a. Melting point: 177 to 178 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 1.06 to 1.92 (10H, m) 2.70 to
2.88 (1H, m) 3.52 (3H, s) 3.86 (3H, s) 3.96 (3H,
s) 6.06 (2H, s) 6.77 (1H, s) 6.79 (1H, d, J = 2.0 H
z) 6.82 (1H, dd, J = 8.0 Hz, 2.0 Hz) 6.94 (1H, d,
J = 8.0 Hz) 7.79 (1H, s) 13.74 (1H, s). IR: υ (CHCl ₃ ) 1724, 1618, 1583, 1514, 1450, 1241,
1169, 1039 cm ^-1 . Elemental analysis (C ₂₈ H ₂₈ O ₈ ): Calculated value; C 68.28%, H 5.73% Measured value; C 68.05%, H 5.77%.

Example 7 1- (3,4-dimethoxyphenyl) -3- (3-ethyl-1-oxope
) -Hydroxy-2- (methoxycarbonyl) -6,7-me
Tolylenedioxynaphthalene: Synthesis step of I-2b 1 (3- (3-ethyl-1-oxopentyl) -1- (3,4-dimethoxyphenyl) -1,2-dihydro-1,4-dihydroxy-2 -
(Synthesis of (methoxycarbonyl) -6,7-methylenedioxynaphthalene: IV-2b) Reaction was carried out in the same manner as in Step 1 of Example 2 to give lactone I
The target compound IV-2b is obtained from I-2 (Reference Example 2) and unsaturated ketoester III-b (Reference Example 4). Melting point: 144.5 to 146.5 ° C (methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.60 to 1.41 (11H, m) 2.13 (1H,
dd, J = 14.2 Hz, 7.0 Hz) 2.28 (1H, dd, J = 14.2 H
z, 7.0 Hz) 3.66 (3H, s) 3.80 (3H, s) 3.82 (3H, s)
3.90 (1H, s) 4.88 (1H, s) 6.07 (2H, s) 6.39 (1H, d
d, J = 8.4 Hz, 2.2 Hz) 6.63 (1H, d, J = 8.4 Hz) 6.9
8 (1H, d, J = 2.2 Hz) 7.18 (1H, s) 7.48 (1H, s).

Step 2 (Synthesis of Compound: I-2b) The same reaction as in Step 2 of Example 1 was conducted to obtain the above compound
The target compound I-2b is obtained from IV-2b. Melting point: 126-128 ° C (methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.83 (6H, t, J = 7.3 Hz) 1.20
~ 1.42 (4H, m) 1.96 ~ 2.16 (1H, m) 2.73 (2H, d, J
= 6.6 Hz) 3.51 (3H, s) 3.86 (3H, s) 3.96 (3H, s)
6.06 (2H, s) 6.72 ~ 6.98 (4H, m) 7.81 (1H, s) 14.
17 (1H, s) IR: υ (CHCl ₃ ) 1730, 1623, 1610, 1586, 1517, 146
3, 1242, 1176, 1043 cm ^-1 Elemental analysis (C ₂₈ H ₃₀ O ₈ ): Calculated value; C 68.00%, H 6.11% Measured value; C 67.88%, H 6.15%.

Example 8 1- (3,4-dimethoxyphenyl) -4-hydroxy-2- (meth)
Cycarbonyl) -6,7-methylenedioxy-3- (1-oxopro
Pyr) naphthalene: Synthesis step of I-2e 1 (1- (3,4-dimethoxyphenyl) -1,2-dihydro-
1,4-Dihydroxy-2- (methoxycarbonyl) -6,7-methylenedioxy-3- (1-oxopropyl) naphthalene: IV-2e
Synthesis of lactone I was carried out in the same manner as in Step 1 of Example 2.
The target compound IV-2e is obtained from I-2 (Reference Example 2) and unsaturated ketoester III-e (Reference Example 10). Melting point: 138-140 ° C (methanol) ¹ H-NMR: δ (CDCl ₃ ) 0.93 (3H, t, J = 7.4 Hz) 2.21
~ 2.50 (2H, m) 3.66 (3H, s) 3.82 (6H, s) 3.94 (1H,
s) 4.86 (1H, br.s) 6.08 (2H, s) 6.42 (1H, dd, J
= 8.4 Hz, 2.2 Hz) 6.65 (1H, d, J = 8.4 Hz) 6.93 (1
H, d, J = 2.2Hz) 7.20 (1H, s) 7.45 (1H, s).

Step 2 (Synthesis of Compound: I-2e) The reaction was carried out in the same manner as in Step 2 of Example 1 to give the above compound
The target compound I-2e is obtained from IV-2e. Melting point: 169-170 ° C (methylene chloride-methanol) ¹ H-NMR: δ (CDCl ₃ ) 1.19 (3H, t, J = 7.2 Hz) 2.81
~ 2.91 (2H, m) 3.52 (3H, s) 3.86 (3H, s) 3.95 (3H,
s) 6.06 (2H, s) 6.72 (1H, s) 6.79 to 6.92 (3H, m)
7.81 (1H, s) 14.36 (1H, s). IR: υ (CHCl ₃ ) 1724, 1619, 1582, 1459, 1175, 103
8, 1025 cm ^-1 Elemental analysis (C ₂₄ H ₂₂ O ₈ ): Calculated value; C 65.75%, H 5.06% Measured value; C 65.55%, H 5.14%.

Example 9 In Example 2 using methanesulfonic acid as dehydrating agent
Synthesis of Compound I-1b produced ( Synthesis of Compound: I-1b) Methane was added to a suspension of 5.58 g (10.0 mmol) of compound IV-1b produced in Step 1 of Example 2 in 23 ml of dry acetonitrile. Add 1.15 g of sulfonic acid and stir at room temperature for 1 hour and 15 minutes. 24 ml of water in the reaction solution
Is added, and the mixture is stirred under ice cooling for 30 minutes, and the precipitated crystals are collected by filtration. The obtained crystals are recrystallized twice from acetone-methanol to obtain 5.04 g (93%) of the desired compound I-1b. Melting point: 128 to 129 ° C. All other physical properties were the same as those produced in Example 2.

The compounds described in the above examples can be summarized as in the table below:

[Table 1]

[0053]

[Table 2]

Next, each test example is shown. The compounds obtained according to Example 1 and Example 2 were tested. Test Example 1 Inhibitory effect of LDL on oxidative denaturation (test and evaluation method) Proceedings of the National Academy of Sciences USA
(Proc. Natl. Acad, Sci, USA) Volume 84, 59
According to the method of Kita et al. Described on page 28 (1987), it was carried out as follows. First, LDL was separated from the blood of New Zealand white rabbits fed a feed containing 0.5% cholesterol for 3 weeks to prepare a phosphate buffered saline solution (final LDL concentration: 0.2 mg protein / ml). After adding an ethanol solution of each test compound to this, copper sulfate (final Cu ²⁺ concentration 0.5 μM) was further added, and the mixture was added at 37 ° C. for 24
Incubated for hours. For each solution after incubation, the lipid peroxide content was measured as a thiobarbituric acid reactive substance (TBA reactive substance), and the compound concentration and LD
From the regression line of L oxidation denaturation inhibition rate, 50% inhibition concentration (IC
₅₀ ) asked. The TBA reaction substance was quantified by measuring the TBA reaction substance in the supernatant obtained by removing the protein from the solution after incubation by the TBA method. The results are shown in Table 3 below. The compound obtained by the method of the present invention has an IC ₅₀ of 10 μM or less, and thus can be said to have a strong antioxidant effect on LDL.

Test Example 2 Cholesterol lowering action (test and evaluation method) Male ICR mice (body weight 30-
40 g), the test compound was added 0.12% (the control group was not added) 1% cholesterol and 0.5% sodium cholate-containing feed was allowed to freely ingest for 7 days, and then blood was collected to obtain total serum cholesterol amount. Clinical Chemistry (Cli
n. Chem.), Volume 20, page 470 (1974). Also, VLD
The total amount of L cholesterol and LDL cholesterol was calculated by subtracting the amount of HDL cholesterol from the total amount of cholesterol. The amount of HDL cholesterol is shown in Clinical Chemistry (Clin. Chem.) Vol. 24, Vol.
It was measured according to the method of Ash and Hentschel et al. Described on page 180 (1978).

The cholesterol-lowering effect of the test compound is
The cholesterol reduction rate obtained by the following formula was used for evaluation.

[Equation 1] The results are shown in Table 3 below.

Table 3 Examples LDL Oxidation Inhibition Total Cholesterol (VLDL + LDL) Cholesterol No. IC ₅₀ (μM) Reduction rate (%) Pool reduction rate (%) 1 0.46 22 61 2 0.40 35 72 Any compound However, since it had an excellent lowering effect on (VLDL + LDL) cholesterol and showed no decrease in HDL cholesterol, it can be said that the compound obtained by the present invention has a strong selective cholesterol lowering effect.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location C07D 307/88 (72) Inventor Sumio Shimizu 5-7-20 Uozakikita-cho, Higashinada-ku, Kobe-shi, Hyogo 904 (72) Inventor Hikozo Iwakura 1-17-2 Shioyakitamachi, Tarumi-ku, Kobe-shi, Hyogo

Claims (8)

[Claims] 1. Formula (II): [Wherein R ² and R ³ are independently a lower alkoxy group, or R ² and R ³ together form an alkylenedioxy group, and R ⁴ is a lower alkoxy group or hydrogen; ⁵ and R ⁶ are each independently a lower alkyl group], and a lactone compound represented by the formula (III): [Wherein R ¹ is an alkyl group, a cycloalkyl group, a cycloalkyl lower alkyl group, or an aralkyl group,
⁷ is a lower alkyl group], and the resulting compound is dehydrated to give a compound of formula (I): [Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ have the same meanings as defined above]. 2. The method of claim 1, wherein R ¹ is C ₁ -C ₆ alkyl, C ₅ -C ₇ cycloalkyl, or C ₅ -C ₇ cycloalkyl C ₁ -C ₆ alkyl. 3. R ² , R ³ and R ⁴ are methoxy,
The method according to claim 1 or 2, wherein R ⁵ , R ⁶ and R ⁷ are methyl. 4. The method according to claim 3, wherein R ¹ is cyclohexyl, 2-ethylbutyl, 1-ethylpropyl, i-propyl, or ethyl. 5. Formula (II): embedded image [Wherein R ² and R ³ are independently a lower alkoxy group, or R ² and R ³ together form an alkylenedioxy group, and R ⁴ is a lower alkoxy group or hydrogen; ⁵ and R ⁶ are each independently a lower alkyl group]. 6. R ² = R ³ = R ⁴ = methoxy, R ⁵ = R ⁶ =
The compound according to claim 5, which is methyl. 7. Formula (III): [Wherein R ¹ is an alkyl group, a cycloalkyl group, a cycloalkyl lower alkyl group, or an aralkyl group,
⁷ is a lower alkyl group]. 8. The compound according to claim ⁷ , wherein R ¹ = 2-ethylbutyl and R ⁷ = methyl.