JP2687398B2 - Aldose reductase inhibitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention has an aldose reductase inhibitory action,
The present invention relates to an aldose reductase inhibitor useful for the treatment of various complications of diabetes such as cataract, retinopathy, neuropathy and renal disorder.

[Prior Art and Problems] In recent years, accumulation of intracellular sorbitol through a polyol pathway, which is a glucose metabolism pathway, has been attracting attention as a cause of various complications in diabetes such as cataract, retinopathy, and renal disorder. The polyol pathway is a metabolic pathway in which aldoses such as glucose and galactose are converted into ketoses such as fructose through polyols such as sorbitol and galactitol, and it is clear that they are widely present in various organs throughout the body by immunohistochemical methods. It has become.

The enzyme that catalyzes the first step in this pathway, the aldose-polyol conversion, is called aldose reductase, and this enzyme is considered the rate-limiting enzyme in the polyol pathway. It has been reported that inhibiting this aldose reductase and reducing the production and accumulation of sorbitol is effective in treating complications in diabetic patients.

Therefore, it has been desired to develop a drug having an aldose reductase inhibitory action.

[Means for Solving the Problem] The present inventors have conducted extensive studies to provide an excellent aldose reductase inhibitor, and as a result, have been widely used clinically. (Artemisiae Capillaris Spica) or other formulas contained in the spikes of the same plant The present invention was completed by discovering that the compound represented by the formula (wherein R represents a hydrogen atom or a methyl group) has an aldose reductase inhibitory action.

That is, the present invention provides (In the formula, R represents a hydrogen atom or a methyl group.) An aldose reductase inhibitor containing a compound represented by the formula (hereinafter, referred to as a compound of the formula) as an active ingredient. For example, the following method can be used to obtain the compound of the formula.

Is extracted with at least one solvent selected from diethyl ether, ethyl acetate, acetone, methanol and ethanol, the residue obtained by distilling the solvent from the resulting extract diethyl ether, ethyl acetate, acetone, methanol, Using at least one solvent selected from ethanol and water as an elution solvent, Diaion HP-20, a porous polymer such as MCI gel CHP20P, Sephadex LH-20
Sephadex, reverse phase silica gel, silica gel, etc.
Column chromatography or high performance liquid chromatography using polyamide or cellulose as a carrier once or several times and fractionating while confirming the target component by thin layer chromatography or high performance liquid chromatography A compound of formula can be obtained by

 Specific examples of the preparation of the compound of formula are shown below.

Example 1 3 kg was extracted with 50 methanol, and the solvent was distilled off from the obtained extract to obtain 700 g of methanol extract. This methanol extract is partitioned and extracted with water and diethyl ether,
The solvent was distilled off from the obtained diethyl ether layer to obtain 285 g of diethyl ether extract. This extract was subjected to column chromatography using silica gel, and was eluted by first increasing the ratio of hexane and then ethyl acetate, and eluting with hexane-ethyl acetate (1: 1) (hereinafter referred to as fraction A). ) And an elution part of ethyl acetate (hereinafter, referred to as fraction B).

 Further, the fractions A and B are each treated with silica gel.
Column chromatography using
Eluate, then chloroform-methanol (100: 1)
Then, a fraction containing the target component was obtained. MCI gel for the fraction
Column chromatography using CHP20P
Concentrate the fractions eluting with tanol-water (7: 3) and
The crystals were crystallized to give 2.5 g of colorless prism crystals. This colorless
The physicochemical properties of prismatic crystals are described in the literature [Pharmaceutical journals,96
(7), 841 (1976)], the compound of formula
Consistent with that of laricin.

Specific Example 2 The fraction B obtained in Specific Example 1 was eluted with chloroform-methanol (100: 1), and the fraction containing the target component was recrystallized from methanol to obtain 180 mg of colorless needle crystals. The physicochemical properties of these colorless needles are described in the literature [Pharmaceutical Journal, 96 (7), 841.
(1976)] and was identical to that of the compound of formula 7-methylcapillarisin.

Next, the fact that the compound of the formula has an aldose reductase inhibitory action will be described with reference to experimental examples.

Experimental Example A 6-week-old Wistar male rat was killed under ether anesthesia, and the lens was immediately removed and stored at -20 ° C.

The lens is a 135 mM sodium-potassium-phosphate buffer solution (pH 7.
It was homogenized at 0) and centrifuged at 30,000 rpm for 30 minutes. The supernatant was used as a sample for inhibiting aldose reductase activity. All the above operations were performed at 4 ° C, and the samples were stored at -20 ° C.

The measurement of aldose reductase activity was performed by
frane) et al. [Biochemical Medicine, 32 , 99-105.
(1984)]. That is, 100 mM lithium sulfate, 0.03 mM NADPH (reduced nicotinamide adenine dinuc
leotide phosphate) and 800 mM of 135 mM sodium-potassium-phosphate buffer (pH 7.0) prepared so as to contain 20 mM glucose as a substrate, 100 μm of the above sample and the compounds of the formulas obtained in the above specific examples 1 and 2 respectively. Final concentration of 1.0 × 10 ^{-5 to} 4.0 × 10 ^-7 M in dimethyl sulfoxide
100 μl of the drug solution, which was dissolved so as to be, was added to each and reacted at 30 ° C. for 30 minutes. Next, 0.5N hydrochloric acid 0.3ml
Was added to stop the reaction, and 1 ml of 6N sodium hydroxide containing 10 mM imidazole was added to generate NADP (oxidized nicotinamide adenine dinine
30 minutes later, the fluorescence intensity was measured. The fluorescence intensity was measured at room temperature using a spectrophotometer F-4000 (manufactured by Hitachi, Ltd.) under the conditions of an excitation wavelength of 360 nm and a fluorescence wavelength of 460 nm.

Further, the fluorescence intensity measured by the same reaction as above was used as a control value except that dimethyl sulfoxide was added instead of the solution of the compound of the formula obtained in Examples 1 and 2.

Aldose reductase is a DL-
It is an enzyme that converts glyceraldehyde or glucose into a polyol, and NADPH changes into NADP along with this reaction. Therefore, if NADP is low, aldose reductase is inhibited.

The results are shown in the table below as the inhibition rate (%) and 50% inhibition concentration (hereinafter referred to as IC ₅₀ ) with respect to the control.

Next, when an acute toxicity test of the compounds of the formulas obtained in Examples 1 and 2 by oral administration was carried out using male ICR mice, no death occurred by oral administration of 1 g / kg.

As described above, the compound of the formula has extremely low toxicity and high safety.

Next, the dosage and formulation of the compound of the formula will be described.

The compounds of the formula can be administered to animals and humans as such or together with conventional pharmaceutical carriers.

The administration form is not particularly limited and may be appropriately selected and used as needed. Examples thereof include oral preparations such as tablets, capsules, granules, fine granules and powders, and parenteral preparations such as injections and suppositories. Can be

In order to exert the intended effect as an oral agent, it depends on the patient's age, body weight and degree of illness, but usually 5 to 500 mg as the weight of the compound of formula is taken in divided doses several times a day in adults. Seems appropriate.

Oral preparations such as tablets, capsules, granules and the like can be produced according to a conventional method using, for example, starch, lactose, sucrose, mannitol, carboxymethyl cellulose, corn starch, inorganic salts and the like.

In this type of preparation, in addition to the above-mentioned excipients, a binder,
Disintegrant, surfactant, lubricant, fluidity enhancer, flavoring agent,
Coloring agents, fragrances and the like can be used. Specific examples are as follows.

[Binder] Starch, dextrin, gum arabic powder, gelatin, hydroxypropyl starch, methyl cellulose,
Sodium carboxymethylcellulose, hydroxypropylcellulose, crystalline cellulose, ethylcellulose, polyvinylpyrrolidone, macrogol.

[Disintegrant] Starch, hydroxypropyl starch, sodium carboxymethylcellulose, calcium carboxymethylcellulose, carboxymethylcellulose, low-substituted hydroxypropylcellulose.

[Surfactant] Sodium lauryl sulfate, soybean lecithin, sucrose fatty acid ester, polysorbate 80.

[Lubricant] Talc, wax, hydrogenated vegetable oil, sucrose fatty acid ester, magnesium stearate, calcium stearate, aluminum stearate, polyethylene glycol.

[Fluidity promoter] Light anhydrous silicic acid, dried aluminum hydroxide gel, synthetic aluminum silicate, magnesium silicate.

In addition, the compound of the present invention is a suspension, emulsion,
It can be administered as a syrup or an elixir, and these various dosage forms may contain a flavoring agent and a colorless agent.

In order to exert the desired effect as a parenteral agent, it depends on the patient's age, body weight, and degree of disease, but usually in adults, the weight of the compound of formula is 0.5 to 100 mg / day by intravenous infusion or infusion. Injection, subcutaneous injection, and intramuscular injection seem appropriate.

This parenteral preparation is manufactured according to a conventional method, and is generally used as a diluent in distilled water for injection, physiological saline, glucose solution, vegetable oil for injection, sesame oil, peanut oil, soybean oil, corn oil, propylene glycol, polyethylene glycol, etc. Can be used. Further, if necessary, a bactericide, a preservative, and a stabilizer may be added. Further, from the viewpoint of stability, this parenteral preparation can be frozen after filling into a vial or the like, water can be removed by a usual freeze-drying technique, and a liquid preparation can be prepared from the freeze-dried product immediately before use. Further, if necessary, an isotonic agent, a stabilizer, a preservative, a soothing agent, and the like may be appropriately added.

Examples of other parenteral preparations include liquid preparations for external use, ointments such as ointments, suppositories for rectal administration, and the like, and are produced according to a conventional method.

Example 1 Corn starch 44 g Crystalline cellulose 40 g Carboxymethyl methylcellulose calcium 5 g Light anhydrous silicic acid 0.5 g Magnesium stearate 0.5 g Compound of formula 10 g Total 100 g Then, the mixture was compressed and molded to obtain 200 mg tablets.

Each tablet contains 20 mg of the compound of the formula, and 5 to 25 tablets for adults are to be taken in several divided doses per day.

Example 2 Crystalline cellulose 84.5 g Magnesium stearate 0.5 g Carboxymethyl cellulose calcium 5 g Compound of formula 10 g Total 100 g According to the above-mentioned prescription, a part of and was uniformly mixed, compressed and crushed, The remaining amounts of and were added and mixed, and the mixture was compression molded with a tableting machine to give tablets of 200 mg each.

Each tablet contains 20 mg of the compound of the formula, and 5 to 25 tablets for adults are to be taken in several divided doses per day.

Example 3 Crystalline cellulose 34.5 g 10% Hydroxypropyl cellulose ethanol solution 50
g Carboxymethyl methylcellulose calcium 5 g Magnesium stearate 0.5 g Compound of formula 10 g Total 100 g According to the above recipe, and are mixed uniformly,
The mixture was wetted by a conventional method, granulated by an extrusion granulator, dried and crushed, mixed with each other, and compression-molded with a tableting machine to obtain a tablet of 200 mg per tablet.

Each tablet contains 20 mg of the compound of the formula, and 5 to 25 tablets for adults are to be taken in several divided doses per day.

Example 4 Corn starch 84 g Magnesium stearate 0.5 g Carboxymethyl cellulose calcium 5 g Light anhydrous silicic acid 0.5 g Formula compound 10 g Total 100 g According to the above-mentioned recipe, the ingredients ( 1) to (2) were uniformly mixed and compression-molded with a compression molding machine. Then, it was crushed by a crusher and sieved to obtain a granule.

1 g of this granule contains 100 mg of the compound of the formula, and 0.5 to 5 g for adults is to be taken in several divided doses per day.

Example 5 Crystalline cellulose 40 g 10% Hydroxypropyl cellulose ethanol solution 50
Compound of the formula g 10 g total 100 g According to the above-mentioned recipe, were mixed uniformly and mixed. After granulation by an extrusion granulator, the granules were dried and sieved to obtain granules.

1 g of this granule contains 100 mg of the compound of the formula, and 0.5 to 5 g for adults is to be taken in several divided doses per day.

Example 6 Corn starch 89.5 g Light anhydrous silicic acid 0.5 g Compound of the formula 10 g Total 100 g According to the above-mentioned formulation, ~ was uniformly mixed, and 200 mg was filled in No. 2 capsule.

One capsule of this capsule contains 20 mg of the compound of the formula, and 5 to 25 capsules per day for adults are to be taken in several divided doses.

Example 7 Distilled water for injection Appropriate amount Glucose 200 mg Compound of formula 50 mg Total amount 5 ml After dissolving and in distilled water for injection, the mixture was poured into an ampoule of 5 ml and autoclaved at 121 ° C. for 15 minutes to obtain an injection. It was

 ─────────────────────────────────────────────────── --Continued front page (56) References Phytochemistry, 23 [9] (1984) p. 1885-1888 Arch, Biochem. Biops. , 239 [2] (1985) p. 491-496

Claims (1)

(57) [Claims] (1) Expression (In the formula, R represents a hydrogen atom or a methyl group.) An aldose reductase inhibitor containing a compound represented by the formula as an active ingredient.