JP2000086653A - Disaccharide hydrolase inhibitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound useful for improving diabetes as a disaccharide hydrolase inhibitor through suppressing hyperglycemioc condition after meal owing to retarding carbohydrate absorption via digestive tract as a result of inhibiting the hydrolysis of carbohydrates because of having high disaccharide hydrolase inhibitory activity. SOLUTION: This new compound is represented by the formula which is obtained, for example, by isolation/purification from the roots or trees of Salacia reticulata; specifically, for example, the crude or fine chips of the roots or trees of the above plant are immersed in an organic solvent (pref. a 60-90% lower alcohol), and the resulting extract solution is concentrated and then subjected to column chromatography or the like. It is preferable that the compound of the formula is orally administered to an adult patient at 2-20 mg at a time in one to four portions a day.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel compound and a disaccharide hydrolase inhibitor useful as a disaccharide hydrolase inhibitor, particularly a disaccharide hydrolase inhibitor containing kotalanol as an active ingredient.

[0002]

2. Description of the Related Art In recent years, the number of diabetic patients in Japan has been increasing.
It has increased rapidly, and when including the number of potential patients, about 60
It is estimated that there are 10,000 people. The basics of diabetes treatment are diet therapy and exercise therapy, but these therapies are difficult to achieve as expected. Also, the majority of diabetics have non-insulin dependent diabetes. In the early stage of this diabetes, fasting blood sugar levels are not so high, but it is thought that sustained high postprandial blood sugar levels cause impaired pancreatic insulin secretion ability and reduced insulin sensitivity. As a result, postprandial hyperglycemia is further promoted, the fasting blood glucose level is also increased, and diabetes is exacerbated.
Thus, improving postprandial hyperglycemia halts the progression of diabetes and results in an improvement.

[0003] Carbohydrates in the diet are digested and decomposed into monosaccharides such as glucose in the upper small intestine, and then are rapidly absorbed. Therefore, if this carbohydrate hydrolysis is inhibited, absorption of carbohydrate is delayed, and postprandial hyperglycemia can be suppressed. Drugs such as acarbose have been developed as drugs that inhibit the hydrolysis of carbohydrates and suppress postprandial hyperglycemia. However, these drugs have a problem that they have side effects such as diarrhea, abdominal bloating, and liver damage.

On the other hand, the present inventors have proposed Kotala Hinbutu (Kotala), which has been used as a Ayurvedic herbal medicine in Indian traditional medicine for thousands of years for the prevention and treatment of diabetes.
himbutu) (Salacia reticulata root) from among salacinol (salacinol), which has disaccharide hydrolase inhibitory activity
) Was isolated [Yoshikawa M. et al., Tetrahedron Le
tt., 38, 8367 (1997)] aim to develop a more potent and safe disaccharide hydrolase inhibitor.

[0005]

Accordingly, an object of the present invention is to provide a novel compound useful as a disaccharide hydrolase inhibitor. Another object of the present invention is to provide a disaccharide hydrolase inhibitor.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to solve the above problems, and found that a compound having a novel disaccharide hydrolase inhibitory activity different from salacinol in Kotara hinbutsu (Hereinafter referred to as kotalanol), and found that kotalanol has a stronger ability to inhibit disaccharide hydrolase than salacinol, thereby completing the present invention.

That is, the present invention is as follows. The following formula [1]

[0008]

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A compound represented by the formula: The following formula [1]

[0010]

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A disaccharide hydrolase inhibitor comprising as an active ingredient a compound represented by the formula:

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Kotalanol is contained, for example, in the roots and trees of Salacia reticulata, and can be obtained by isolation and purification from the plant.

The method for extracting kotalanol is not particularly limited. For example, an organic solvent or water is added to a rough or fine cut of Salacia reticulata roots and trees, and immersion is performed.
After leaching for 4 hours, the residue is obtained by removal. Extraction is
It may be performed once or plural times (for example, three or four times). The extraction is usually performed at 75-85 ° C. Sala
The mixing ratio of cia reticulata and the solvent is usually 1: 3 to 1:
It is about 15.

Examples of the organic solvent used for the extraction include water-soluble organic solvents such as alcohols and acetone, as well as aromatic hydrocarbons, aliphatic hydrocarbons, ethers, ketones and esters. However, it is preferable to use alcohols from the viewpoint of safety after extraction. As the alcohols, lower alcohols such as methanol, ethanol, and butanol are preferable. These lower alcohols can be used alone, but are more preferably used by mixing with water. The mixing ratio of the lower alcohol and water is not particularly limited.
90% lower alcohols are preferred.

A concentrate is obtained from the obtained extract by subjecting the solvent to, for example, distillation under reduced pressure or the like, and the concentrate is further subjected to column chromatography or the like to isolate kotalanol. The concentrate may be pretreated before it is subjected to column chromatography. The pretreatment is performed, for example, by dispersing the concentrate in water, adding an organic solvent or the like insoluble in water such as ethyl acetate, and shaking to remove fat-soluble components soluble in the organic solvent. be able to. The water-soluble fraction thus pretreated is concentrated under reduced pressure and then subjected to column chromatography or liquid chromatography (HPLC).

The type of adsorbent that can be used for column chromatography or HPLC is not particularly limited as long as it can isolate kotalanol, and can be appropriately selected. For example, silica gel and alumina are used. .

The mobile phase that can be used for column chromatography or HPLC can be appropriately selected depending on the type of adsorbent, the purity of kotalanol, and the like.

Kotalanol has a disaccharide hydrolase inhibitory effect on mammals such as humans, cows, and horses, and is useful as a disaccharide hydrolase inhibitor. Disaccharide hydrolase inhibitors inhibit the hydrolysis of carbohydrates and slow the absorption of carbohydrates from the gastrointestinal tract, thereby suppressing postprandial hyperglycemia, thereby preventing the progression of diabetes and the pathology of diabetes Can be improved. When Kotalanol is used as a disaccharide hydrolase inhibitor, pharmaceutically acceptable additives (eg, carriers, excipients, diluents, binders, lubricants, solubilizers, stabilizers, preservatives, etc.) And the like can be appropriately formulated and formulated into a form suitable for administration of powders, granules, tablets, capsules, syrups, injections and the like using a known method, and can be administered orally or parenterally.

In the above-mentioned preparation, an effective amount of kotalanol is incorporated. The dose is appropriately selected depending on the administration route, symptoms, weight or age of the patient, for example,
When administered orally to an adult patient, it is desirable to administer about 2 to 20 mg per dose of kotalanol in 1 to 4 divided doses per day.

[0020]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, and the effects of the present invention will be clarified by test examples. However, these are merely examples, and the present invention is not limited thereto. Not something.

Example 1 Method of extracting kotalanol 20 kg of root and tree of Salacia reticulata from Sri Lanka
, Add 100 L of 80% methanol and heat (80 ° C,
Extraction was performed for 3 hours), followed by filtration to obtain an extract. The same operation was repeated four times in total. The extracts were combined, and the solvent was distilled off under reduced pressure to obtain 2.5 kg of an 80% methanol extract.
After dispersing the 80% methanol extract in 10 L of water, the fat-soluble component was extracted and removed using 10 L of ethyl acetate. The aqueous layer was concentrated under reduced pressure to obtain 2.0 kg of a water-soluble fraction. This water-soluble fraction was subjected to silica gel chromatography [chloroform-methanol-water mixture (6: 4: 1) →
(5: 5: 1) → (3: 7: 1)] and then NH chromatrex chromatography (Fuji Silysia Ltd.)
Chromatorex NH) [acetonitrile-water mixture (6: 4)] and HPLC [YMC C
o. , Ltd., YMC-Pack polyami
ne II (250 × 10 mm id), acetonitrile-water mixture (7: 3)], and cotalanol 4
0 mg was obtained.

Kotalanol obtained by the above extraction method is a colorless fine crystal, and its physicochemical properties are as follows. ^{mp. 173.7 ~175.0 ℃ 1 H-} NMR (500MHz, pyridine-d 5) δ 4.31 (2H, br s), 5.
08 (1H, dd-like), 5.16 (1H, br s), 4.64 (1H, t-like),
4.51 (2H, dd-like), 4.65 (1H, dd, J = 3.0, 12.8Hz), 4.9
3 (1H, dd, J = 3.1, 12.8Hz), 5.24 (1H, m), 5.64 (1H, dd,
J = 0.9, 8.5Hz), 5.12 (1H, br s), 5.86 (1H, dd-like),
4.88 (1H, ddd-like), 4.25 (1H, dd, J = 5.8, 11.0Hz), 4.
50 (1H, dd, J = 7.9, 11.0Hz) .IR (KBr, CHCL ₃ ) 3410, 1258, 1233, 1071, 994 cm ^{-1 13} C-MNR (125MHz, pyridine-d ₅ ) 60.
0, 65.3, 67.4, 70.5, 71.3, 72.2, 72.5, 77.9, 78.1,
79.4. (Α) _D ²⁷ +11.5 ° (MeOH) HRMS Calcd for C ₁₂ H ₂₄ O ₁₂ S ₂ SIMS (m / z) 345, 425, 447, 469.

Test Example 1 Evaluation test of disaccharide hydrolase inhibitory effect

Preparation of Enzyme Solution The method of Kesseler et al. [Biochem. Biophys. Acta., 5] was used from the jejunum of male Wistar rats (body weight 150-300 g).
06 , 136 (1978)] was used as a crude enzyme. The brush border membrane was washed with 0.1 M maleate buffer (pH
6.0) at a rate of 25-50 nmol / mL / m
In, the substrate was used after being diluted to a concentration that hydrolyzes the substrate.

Measurement of Enzyme Activity A test substance (kotalanol, salacinol, acarbose) solution (0.05 to 1) was added to 100 μL each of a substrate solution (maltose, sucrose: 74 mM, isomaltose: 7.4 mM).
(00 μg / mL) and pre-warmed at 37 ° C. for 2-3 minutes. After adding 50 μL of the crude enzyme solution and reacting for 30 minutes, 800 μL of water was added, and the mixture was heated in a water bath at 92 to 97 ° C. for 2 minutes to inactivate the enzyme. Separately, 100 μL of each substrate solution, 50 μL of each test substance solution, and 5
After adding 0 μL, immediately add 800 μL of water, and add
The mixture was heated in a water bath at 97 ° C. for 2 minutes, and the enzyme inactivated was blinded. The amount of generated glucose was measured by a glucose oxidase method (manufactured by Wako Pure Chemical Industries, Ltd., glucose CII Test Wako). From the obtained values, the concentration (IC ₅₀ ) at which the enzyme activity was inhibited by 50% was determined. Table 1 shows the results.

[0026]

[Table 1]

From the above results, kotalanol exhibited superior enzyme activity inhibition on all substrates (maltose, sucrose, isomaltose) as compared to salacinol and acarbose.

Formulation Example 1 Tablets Tablets are formed by mixing the following ingredients and forming the resulting mixture by the tableting method. Amount per tablet (mg) Kotalanol 5 Corn starch 20 Hydroxypropyl cellulose 3 Magnesium stearate 2 Lactose Dosage meter 150

[0029]

EFFECTS OF THE INVENTION Kotalanol, a novel compound, has a high inhibitory effect on disaccharide hydrolase, inhibits the hydrolysis of carbohydrates and delays the absorption of carbohydrates from the gastrointestinal tract. Can be suppressed. Therefore, a disaccharide hydrolase inhibitor containing kotalanol as an active ingredient can prevent the progress of diabetes and improve diabetes.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hisashi Matsuda 22-2 Ono-Kanetsukidacho, Yamashina-ku, Kyoto-shi, Kyoto Prefecture Eagle Court Ono 408 F-term (Reference) 4C086 AA01 AA02 AA03 BB02 MA01 MA04 NA14 ZC20 ZC35 4C088 AB11 AC06 AC11 BA34 NA14 ZC20 ZC35

Claims (2)

[Claims] [Claim 1] The following formula [1] A compound represented by the formula: 2. The following formula [1] A disaccharide hydrolase inhibitor comprising, as an active ingredient, a compound represented by the formula: