JPH06305971A - Hypoglycemic agent - Google Patents

Abstract

PURPOSE:To provide a highly stable hypoglycemic agent containing a specific dihydrochalcone derivative as an active component, exhibiting the increasing action on urine sugar and the reducing action on blood sugar, which are attributed to the inhibition of sugar reabsorption at a kidney and useful as a treating and prophylactic agent for diabetes, etc. CONSTITUTION:A mixture of 2'-O-(2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl)-6'- hydroxyacetophenone, p-ethoxybenzaldehyde and ethanol is incorporated with 50% aqueous solution of potassium hydroxide dropwise under stirring and the mixture is further stirred over night at a room temperature. The solvent is removed from the reaction mixture under reduced pressure. The residue is incorporated with water and diethyl ether and stirred and the water layer is separated. After the neutralization, the water layer is extracted with ethyl acetate. The extract is subjected to catalytic hydrogenation with a vanadium- carbon catalyst in ethanol and the reaction product is purified by silica gel chromatography to obtain a dihydrochalcone derivative of formula (R is H, OH or lower alkoxy). Subsequently this, as an active component, is formulated by using a pharmaceutical carrier to obtain the objective hypoglycemic agent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a hypoglycemic agent.

[0002]

2. Description of the Related Art Diet therapy is essential for the treatment of diabetes, but if this alone does not provide sufficient control, insulin or an oral diabetes drug is used as needed. As a diabetes drug, a biguanide compound and a sulfonylurea compound have been conventionally used. However, the biguanide compound has a side effect of lactic acidosis and the sulfonylurea compound has a serious hypoglycemia, and development of a new therapeutic agent for diabetes without such defects is desired.

[0003] In recent years, glucose glucose toxicology (Glucose Toxicity Theo) has been suggested that hyperglycemia itself is involved in the onset and progress of diabetes.
ry) has been proposed. That is, chronic hyperglycemia causes abnormalities in both insulin secretion and insulin action, which further raises blood glucose and progresses diabetes [diabetologia (Diabetolog.
ia), 28, 119 (1985)].

This theory has been verified as follows. That is, it was confirmed that if the blood glucose of a diabetic animal is kept normal for a long time without using insulin, the condition of the diabetic animal is improved and normalized [J. Clin. Inve (J. Clin. Inve
st. ), 79, 1510 (1987),
Ibid., 80, 1037 (1987), Id., 8
7, p. 561 (1991), etc.]. In these verification experiments, phlorizin is used subcutaneously as a reagent for keeping blood sugar normal.

Floridin is a glycoside contained in the bark and root bark of plants such as apples and pears, and has been discovered in the last century and variously studied. Recently, it was found to be an inhibitor of the Na ⁺ -glucose cotransporter that exists only in the chorion of the intestine and kidney, and in this experiment, phlorizin inhibits renal glucose reabsorption and promotes glucose excretion. It is interpreted as having corrected the hyperglycemia.

However, when phlorizin is administered orally, most of it is hydrolyzed into aglycone, phloretin and glucose, and the proportion absorbed as phlorizin is small, and the urinary glucose excretion action is very weak. It is known that phloretin, which is an aglycone, strongly inhibits the facilitative diffusion type sugar transporter. For example, it has been reported that intravenous administration of phloretin to rats reduces brain glucose concentration. [Stroke, 1st
4, p. 388 (1983)], it is conceivable that long-term use of this may adversely affect various tissues. For that reason, no attempts have been made to use phlorizin for the prevention or treatment of diabetes.

2'-O- (β-D-glucopyranosyl) -6'-hydroxydihydrochalcone, 2'-O
-(Β-D-Glucopyranosyl) -4,6′-dihydroxydihydrochalcone and 2′-O- (β-D-glucopyranosyl) -6′-hydroxy-4-methoxydihydrochalcone are photophosphorylated in chloroplasts. Known to inhibit [Biochemistry (Bioche
Mistry), Vol. 8, p. 2067 (1969)
Year)〕. It is also known that 2'-O- (β-D-glucopyranosyl) -4,6'-dihydroxydihydrochalcone inhibits Na ⁺ -glucose cotransporter in the kidney [eg, Biokimica. E. Biophysica Actor (Biochim. Biophys.A)
71), p. 688 (1963)]. However, nothing is described that the above compound has an action of increasing urinary glucose even after oral administration.

[0008]

DISCLOSURE OF THE INVENTION According to the present invention, a dihydrochalcone derivative having an excellent urinary sugar-increasing effect even when orally administered, and the aglycone having an extremely weak inhibitory effect on a facilitative diffusion-type sugar transport carrier is effective. The present invention provides a hypoglycemic agent as an ingredient.

[0009]

The present invention has the general formula [I]

[0010]

[Chemical 2]

The present invention relates to a hypoglycemic agent containing a dihydrochalcone derivative represented by R (representing a hydrogen atom, a hydroxy group or a lower alkoxy group) as an active ingredient.

The dihydrochalcone derivative [I], which is the active ingredient of the present invention, exhibits an excellent hypoglycemic action based on the action of increasing urinary glucose. For example, when the active ingredient [I] of the present invention was administered to rats, the amount of glucose excreted in the urine in 24 hours was about 5 to 30 times that when phlorizin was administered. Further, when the active ingredient of the present invention was orally administered to glucose-loaded diabetic mice, the rise in blood glucose level was significantly suppressed. Therefore, the hypoglycemic agent of the present invention is useful for treating / preventing diabetes. Such an action of increasing the urinary glucose of the active ingredient [I] of the present invention is considered to be due to inhibition of glucose reabsorption in the kidney, and has a characteristic that conventional hypoglycemic agents do not have.

The dihydrochalcone derivative which is the active ingredient of the present invention has a low toxicity, for example, 2'-O- (β-
D-glucopyranosyl) -6′-hydroxy-4-methoxydihydrochalcone at a rate of 1000 mg / kg,
No oral death was observed in rats after oral administration for 28 days.

Further, aglycone, which is a hydrolyzate of the active ingredient of the present invention, is different from phloretin in that it has a remarkably weak inhibitory effect on sugar uptake. For example, human erythrocyte and D- [3- ³ H] glucose for 1 minute, were examined by measuring the radioactivity of erythrocyte uptake sugar in erythrocytes, if the time sample compound not added was 100, the present invention 2 ', which is the aglycone of the active ingredient of
4,6'-trihydroxydihydrochalcone is 92.
7,2 ', 6'-dihydroxy-4-methoxydihydrochalcone is 91.0, while phloretin is 13.
It was 7. Therefore, the inhibitory effect of the aglycone of the active ingredient of the present invention on glucose uptake in human erythrocytes is significantly smaller than that of phloretin, which is an aglycone of phlorizin, and even if the active ingredient of the present invention is partially hydrolyzed, the concentration of sugar in the tissue is high. It is considered that the decrease of the is very unlikely to occur.

Specific examples of the dihydrochalcone derivative which is the active ingredient of the present invention include R 1 in the general formula [I], which is a hydrogen atom, a hydroxy group, or a methoxy group, an ethoxy group, an isopropoxy group, and the like. The compound which is the lower alkoxy group of 4 can be mentioned.

Compounds having excellent therapeutic effects include:
R is a hydrogen atom, 4-hydroxy group, 4-methoxy group, 4
Compounds which are 4-lower alkoxy groups such as -ethoxy group or 4-isopropoxy group can be mentioned, and as compounds having particularly excellent therapeutic effect, R is 4-lower group such as hydrogen atom or 4-methoxy group. The compound which is an alkoxy group can be mentioned.

The hypoglycemic agent of the present invention can be administered orally or parenterally, and can be made into a suitable formulation by using a pharmaceutical carrier usually used for oral and parenteral administration. Such pharmaceutical carriers include, for example, binders (syrup, gum arabic, gelatin, sorbit, tragacanth, polyvinylpyrrolidone, etc.), excipients (lactose, sugar, corn starch, potassium phosphate, sorbit, glycine, etc.), lubricants ( Examples thereof include magnesium stearate, talc, polyethylene glycol, silica, etc., disintegrating agents (potato starch, etc.), wetting agents (sodium lauryl sulfate, etc.) and the like. When administered orally, these pharmaceutical preparations may be solid preparations such as tablets, capsules, powders and granules, or liquid preparations such as solutions, suspensions and emulsions. On the other hand, for parenteral administration, for example, distilled water for injection, physiological saline, aqueous glucose solution or the like can be used to prepare an injection or drip.

The dose of the dihydrochalcone derivative [I] varies depending on the method of administration, age, weight, condition of the patient or degree of disease, but the daily dose is usually 1 to 100 mg in the case of oral administration. / Kg, especially 5
40 mg / kg, 0.1 to 50 for parenteral administration
It is preferably mg / kg, especially 0.5 to 10 mg / kg.

The dihydrochalcone derivative [I], which is the active ingredient of the present invention, can be prepared according to the general formula [II] according to the method described in, for example, Biochemistry, Volume 8, page 2067 (1969).

[0020]

[Chemical 3]

(However, OX represents an optionally protected hydroxyl group) and an acetophenone derivative represented by the general formula [III]

[0022]

[Chemical 4]

(However, R has the same meaning as described above.)
The aldehyde compound represented by the formula (1) is condensed in a solvent in the presence of a base (alkali metal hydroxide or the like), and when OX is a protected hydroxyl group, the protecting group is removed by a conventional method to give a compound represented by the general formula [IV]

[0024]

[Chemical 5]

(However, R has the same meaning as above.)
After producing the compound represented by the formula (1), the compound can be produced by catalytic hydrogenation using a catalyst (palladium-carbon or the like) in a solvent or reduction with a metal hydride such as sodium tellurium hydride.

The starting material compound [II] is, for example, a compound in which OX is an acetyloxy group, according to the method described in the above-mentioned Biochemistry, Volume 8, page 2067 (1969), 2 ', 6'-. Dihydroxyacetophenone is reacted with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide in water-containing acetone in the presence of sodium hydroxide, or 2 ′, 6′-
It can be produced by heating dihydroxyacetophenone and 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide in toluene in the presence of cadmium carbonate and refluxing.

In the present invention, the lower alkoxy group includes those having 1 to 6 carbon atoms, especially 1 to 4 carbon atoms. In addition, in the present specification, “2′-O- (β-
"D-glucopyranosyl)-" means "2 '-(β-D-
Glucopyranosyloxy)-".

[0028]

[Action]

Experimental Example (Hypoglycemic action in mice) (Experimental method) A 15-week-old male diabetic mouse fasted overnight
Oral administration of test compound to 6 mice per group (Dose: 100m
g / kg), followed immediately by subcutaneous administration of glucose (2 g
/ Kg / 5 ml physiological saline). Immediately before administration and after a certain period of administration, blood was collected from the tail vein under anesthesia, and the blood glucose level was measured by the glucose oxidase method. On the other hand, the one to which a solvent was administered instead of the test compound was used as a control.

The results are shown in Table 1.

(Sample compound) 2'-O- (β-D-glucopyranosyl) -6'-hydroxy-4-methoxydihydrochalcone [ie 2 '-(β-D-glucopyranosyloxy) -6'] -Hydroxy-4-methoxydihydrochalcone]

[0031]

[Table 1]

From the above results, it can be seen that the blood glucose level in the sample-administered group is significantly lower than that in the sample-non-administered group.

(Increase in urine glucose in rat) (Experimental method) Male SD rat (6 weeks old, 1 group 3-5)
The test compound administration solution was orally administered (dosage: 100 mg / kg) to 8 animals at a rate of 5 ml / kg twice every 8 hours. The sample administration liquid was prepared by adding Tween 80 to the sample and then suspending it in purified water. To the control group, only purified water containing Tween 80 was administered. Twenty-four hours after the first administration, the rats were placed in a metabolic gauge and urine was collected. For urine, after measuring the urine volume, remove contaminating substances by centrifugation, and then
The urine sugar concentration was measured with an analyzer (manufactured by Apec).
The urine sugar (mg) excreted in 24 hours was calculated from the urine volume (ml) and the urine sugar concentration (mg / dl). In addition, 2 of the control group
The urine sugar in 4 hours was 0-6 mg.

The results are shown in Table 2.

[0035]

[Table 2]

As is clear from the above results, the group to which the dihydrochalcone derivative [I] which is the active ingredient of the present invention was administered, the urinary sugar was increased by about 5 to 30 times compared to the group to which phlorizin was administered. I understand.

Production Example 1 (1) 2'-O- (2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl) -6'-hydroxyacetophenone 1000 mg, p-ethoxybenzaldehyde 466 mg, ethanol 5 to 10 ml of mixture
1 ml of 0% aqueous potassium hydroxide solution is added dropwise, and the mixture is stirred at room temperature overnight. The solvent is distilled off under reduced pressure, water and diethyl ether are added to the residue, the mixture is stirred, and the aqueous layer is separated. The ice-cooled lower aqueous layer is neutralized with 10% hydrochloric acid and then extracted with ethyl acetate. The obtained organic layer is washed with water and dried, and then the solvent is distilled off to obtain 685 mg of crude 2′-O- (β-D-glucopyranosyl) -6′-hydroxy-4-ethoxychalcone.

(2) The above crude 2'-O- (β-D-glucopyranosyl) -6'-hydroxy-4-ethoxychalcone (665 mg) was dissolved in ethanol (20 ml) to obtain 10
% Catalytically reducing hydrogen under atmospheric pressure using 0.3 g of palladium-carbon as a catalyst. After removing the catalyst by filtration, the filtrate was concentrated under reduced pressure,
The residue was purified by silica gel column chromatography to give 2'-O- (β-D-glucopyranosyl) -6'-.
Hydroxy-4-ethoxydihydrochalcone 425mg
To get The physical property values are as shown in Table 3.

Production Example 2-6 In the same manner as in Production Example 1, from the corresponding raw material compound to the third
The compounds listed are obtained.

[0040]

[Table 3]

[0041]

[Table 4]

Reference Example 1 A mixture of 5.0 g of 2 ', 6'-dihydroxyacetophenone, 23 g of cadmium carbonate, and 400 ml of toluene was added to a Dean-Stark distillation tube (Dien-Stark).
Reflux while removing the solvent in trap). 50 solvent
After removing ml, 27 g of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide was added, and 1
Reflux for 8 hours. The insoluble material was removed by filtration, the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography to give 2'-O- (2,3,4,6-tetra-O.
10.1 g of -acetyl-β-D-glucopyranosyl) -6'-hydroxyacetophenone are obtained.

M. p. : 200.5 to 201.5 ° C NMR (DMSO-d ₆ ) δ: 1.96 (3H, s),
2.01 (9H, s) 2.35 (3H, s), 4.0
4.3 (3H, m), 4.9-5.1 (2H, m),
5.40 (1H, dd, J = 9.3, 9.8Hz),
5.55 (1H, d, J = 7.8Hz), 6.61 (1
H, d, J = 8.3 Hz), 6.62 (1H, d, J =
8.3 Hz), 7.26 (1H, t, J = 8.3H)
z), 10.81 (1H, s) FABMS (m / z): 483 (MH ⁺ ).

[0044]

INDUSTRIAL APPLICABILITY The dihydrochalcone derivative [I], which is the active ingredient of the present invention, has an action of increasing urinary glucose which is considered to be based on inhibition of glucose reabsorption in the kidney, and thereby exhibits an excellent hypoglycemic action. Furthermore, unlike phlorizin, which is unlikely to undergo hydrolysis in the intestinal tract, it can be effectively used for the treatment or prevention of diabetes in both oral and parenteral administration. In addition, the dihydrochalcone derivative, which is the active ingredient of the present invention, has low toxicity, and its hydrolyzate, aglycone, has a feature that its sugar uptake inhibitory action is extremely weak, and therefore it is highly safe as a medicine.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masanori Inamasu, 3-4, 3-4 Waseda, Misato City, Saitama Prefecture, No. 407 (72) Inventor, Kenji Arakawa 2-38-2, Bessho, Urawa, Saitama 508

Claims (5)

[Claims] 1. A compound represented by the general formula [I]: (However, R represents a hydrogen atom, a hydroxy group or a lower alkoxy group.) A hypoglycemic agent containing a dihydrochalcone derivative represented by the following as an active ingredient. 2. The hypoglycemic agent according to claim 1, wherein R is a hydrogen atom, a 4-hydroxy group or a 4-lower alkoxy group. 3. The hypoglycemic agent according to claim 1, wherein R is a hydrogen atom or a lower alkoxy group. 4. The hypoglycemic agent according to claim 3, wherein R is a hydrogen atom or a 4-lower alkoxy group. 5. The hypoglycemic agent according to claim 1, 2, 3 or 4, which is a therapeutic or preventive agent for diabetes.