WO2010126022A1

WO2010126022A1 - Imidazole derivative

Info

Publication number: WO2010126022A1
Application number: PCT/JP2010/057418
Authority: WO
Inventors: 肇浅沼; 武史小網; 喜功関口; 直哉小野; 明子中尾
Original assignee: 大正製薬株式会社
Priority date: 2009-04-28
Filing date: 2010-04-27
Publication date: 2010-11-04
Also published as: JP5569816B2; JPWO2010126022A1

Abstract

7-Methoxy-6-[5-(4-methylthiazol-2-yl)-3H-imidazol-4-yl]benzothiazole or a pharmaceutically acceptable salt thereof is a novel compound or pharmaceutically acceptable salt thereof which is useful for the prevention or treatment of diseases such as glomerulonephritis, diabetic nephropathy, hepatic fibrosis, hepatic cirrhosis, pulmonary fibrosis, proliferative vitreoretinopathy, scleroderma, and baldness, the prevention or treatment being based on an inhibitory action on ALK 5, which is a TGF-β receptor I.

Description

Imidazole derivatives

The present invention relates to a compound having an inhibitory action on activin receptor-like kinase 5 (ALK5), which is a type I receptor for TGF-β.

Transforming growth factor-β (TGF-β) is a molecule belonging to the TGF-β superfamily together with activin, BMP and the like. There are two types of receptors that transmit signals from TGF-β into cells, type I and type II, both of which have a serine / threonine kinase region in the cell. When TGF-β binds to the receptor, the type II receptor phosphorylates the type I receptor, resulting in activation of the type I receptor and signaling to the nucleus via the Smad2 / 3 pathway or TAB1 / TAK1 pathway Is transmitted.

TGF-β has been shown to have a wide variety of physiological effects. One of them is that it has the effect of accumulating extracellular matrix in tissues through the promotion of production and suppression of degradation of extracellular matrix constituent proteins. Is well known (Non-Patent Document 1). For this reason, continuous enhancement of TGF-β production and activation of the signal transduction system are causes of many fibrotic diseases. For example, in the kidney, TGF-β is deeply involved in renal interstitial fibrosis and glomerulosclerosis in renal diseases such as glomerulonephritis and diabetic nephropathy (Non-patent Documents 2 and 3), In the liver, it has been shown that TGF-β promotes the production of extracellular matrix of nonparenchymal cells and is involved in the development of liver fibrosis and cirrhosis (Non-patent Document 4). In addition, as an etiology of intractable diseases with many fibrosis such as pulmonary fibrosis, proliferative vitreoretinopathy, scleroderma, accumulation of extracellular matrix due to hyperfunction of TGF-β can be mentioned.

Inhibitors of ALK5 have been reported to suppress the accumulation of extracellular matrix induced by TGF-β by blocking the TGF-β / Smad signal (Non-Patent Documents 5 to 7). It is considered useful as a pharmaceutical for treatment or prevention of various diseases associated with fibrosis such as lungs.

On the other hand, TGF-β is known to exhibit a strong growth inhibitory action against many cells such as epithelial cells, vascular endothelial cells, blood cells and lymphocytes (Non-patent Document 1). In hair follicles, it has been reported that hair follicle cell proliferation suppression / apoptosis is induced by increased expression of TGF-β, and the hair cycle shifts from the growth phase to the resting phase. (Non-patent Documents 8 and 9). The applicant of the present application reported that an inhibitor of ALK5 inhibits hair follicle cell growth suppression by TGF-β (Patent Document 1). Therefore, ALK5 inhibitors are considered useful as hair follicle cell growth promoters, hair growth agents, and hair growth agents.

There have been reports on many compounds having an ALK5 inhibitory action (for example, Patent Documents 2 to 4), and Patent Document 1 describes a group of compounds having a structure similar to the compound of the present invention. Compounds are not described.

WO2005 / 085241 WO01 / 62756 WO03 / 087304 WO03 / 042207

The present invention relates to glomerulonephritis, diabetic nephropathy, hepatic fibrosis, cirrhosis, pulmonary fibrosis, proliferative vitreoretinopathy, strong, based on the inhibitory action of AGF5 which is a type I receptor of TGF-β. The object is to provide a novel compound or a pharmaceutically acceptable salt thereof useful for the prevention or treatment of diseases such as dermatosis and alopecia.

As a result of various studies, the present inventors have found that the compound of the present invention has an ALK5 inhibitory action and completed the present invention.

That is, the present invention
(1) 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole or a pharmaceutically acceptable salt thereof.
(2) Yarn containing 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole or a pharmaceutically acceptable salt thereof as an active ingredient A prophylactic or therapeutic agent for diseases such as spherical nephritis, diabetic nephropathy, liver fibrosis, cirrhosis, pulmonary fibrosis, proliferative vitreoretinopathy, scleroderma, or alopecia.
(3) Hair comprising 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole or a pharmaceutically acceptable salt thereof as an active ingredient A follicle cell growth promoter, hair growth agent, or hair growth agent.
It is.

Since the compound of the present invention has an ALK5 inhibitory action, it can block the TGF-β / Smad signal.

It is the figure which showed that the phosphorylated Smad2 level of the Example 1 administration group was significantly lower than that of a base administration group 1 hour after administration. *: P <0.05 (Welch test). It is the figure which showed that the phosphorylated Smad2 level of an Example 1 administration group was significantly lower than that of a base administration group 8 hours after administration. **: p <0.01 (Welch test) It is the figure which showed that the phosphorylated Smad2 level of the comparative example 1 administration group was significantly lower than that of a base administration group 1 hour after administration. *: P <0.05 (Welch test). 8 hours after administration, the level of phosphorylated Smad2 in the group administered with Comparative Example 1 was lower than that in the group administered with the vehicle, but no significant difference was observed between the two groups.

The compound of the present invention, 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole, is a compound having the following structure.

In the present invention, “pharmaceutically acceptable salt” means acetic acid, propionic acid, butyric acid, formic acid, trifluoroacetic acid, maleic acid, tartaric acid, citric acid, stearic acid, succinic acid, ethyl succinic acid, lactobionic acid, gluconic acid , Glucoheptonic acid, benzoic acid, methanesulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid, paratoluenesulfonic acid, lauryl sulfuric acid, malic acid, aspartic acid, glutamic acid, adipic acid, cysteine, N-acetyl Examples include salts with cysteine, hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid, hydrogen iodide, nicotinic acid, oxalic acid, picric acid, thiocyanic acid, undecanoic acid, acrylic acid polymer, carboxyvinyl polymer, and the like.

The compound of the present invention or a pharmaceutically acceptable salt thereof may exist as a solvate. For example, the hydrate of a compound, the hydrate of the pharmaceutically acceptable salt of a compound, etc. are mentioned. These are all included in the present invention.

In order to use the compound of the present invention as a medicament, the compound of the present invention is added with usual excipients, extenders, pH adjusters, solubilizers, etc., and tablets, granules, pills, capsules are added by conventional formulation techniques. , Powders, solutions, suspensions, injections, coatings, etc., and can be administered orally, transdermally or intravenously.

The compound of the present invention can be administered to an adult patient at a dose of 0.01 to 100 mg / kg per day in 1 to several divided doses. This dose can be appropriately increased or decreased depending on the type of disease, patient age, weight, symptoms and the like.

Hereinafter, the present invention will be described in more detail with reference to examples and test examples.

The compound of the present invention can be synthesized, for example, by the method shown below. In addition, silica gel 60N and Chromatorex NH marketed by Kanto Chemical and Fuji Silysia, respectively, were used as “silica gel” and “NH silica gel” when purified using column chromatography.

Example 1
7-Methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole
(1) Synthesis of 6,6-dibromo-5,6-dihydro-4H-benzothiazol-7-one A solution of 5,6-dihydro-4H-benzothiazol-7-one (100.0 g) in acetic acid (880 mL) Bromine (70.2 mL) was added dropwise to the suspension in which hydrobromic acid (35.4 ml, 48%) was added dropwise at room temperature over 1 hour. The reaction mixture was stirred at 40 ° C. to 45 ° C. for 7.5 hours, then cooled to room temperature, and the resulting precipitate was filtered and washed with acetic acid. The suspension obtained by adding water (1.1 L) and ethyl acetate (0.5 L) to the obtained solid is neutralized by adding sodium bicarbonate, and then water (1.0 L) is added and extracted with ethyl acetate. The organic layer was dried over magnesium sulfate. The filtrate obtained by filtration was concentrated to obtain 6,6-dibromo-5,6-dihydro-4H-benzothiazol-7-one (155.4 g) as a light brown powder.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 3.14-3.19 (m, 2 H), 3.21-3.26 (m, 2 H), 9.08 (s, 1 H)

(2) Synthesis of 6-bromobenzothiazol-7-ol To a solution of 6,6-dibromo-5,6-dihydro-4H-benzothiazol-7-one (154.4 g) in tetrahydrofuran (2.5 L), ice Under cooling, 1,8-diazabicyclo [5.4.0] undec-7-ene (222 mL) was added dropwise over 20 minutes, followed by stirring at room temperature for 1.5 hours. Hydrochloric acid (1.6 L, 1.0 N aqueous solution) was added, and the organic layer obtained by extraction with ethyl acetate (5.0 L) was washed with saturated brine, and dried over magnesium sulfate. The filtrate obtained by filtration was concentrated to give 6-bromobenzothiazol-7-ol (110.5 g) as a brown powder.
¹ H NMR (200 MHz, DMSO-d ₆ ) δ ppm: 7.54 (d, J = 8.8 Hz, 1 H), 7.65 (d, J = 8.4 Hz, 1 H), 9.33 (s, 1 H), 10.70 (br s, 1 H)

(3) Synthesis of 6- bromo-7-methoxybenzothiazole To a solution of 6-bromobenzothiazol-7-ol (116 g) in N, N-dimethylformamide (1.1 L) was added potassium carbonate (139 g) under ice cooling. Then, methyl iodide (35 mL) was added dropwise, and the mixture was stirred at room temperature for 12.5 hours. Water was added to the reaction mixture, and the organic layer extracted three times with ethyl acetate was washed with saturated brine and dried over magnesium sulfate. The filtrate obtained by filtration was concentrated to obtain 6-bromo-7-methoxybenzothiazole (100 g) as a light brown powder.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 4.05 (s, 3 H), 7.64-7.70 (m, 1 H), 7.74-7.79 (m, 1 H), 8.96 (s, 1 H)

(4) Synthesis of 7-methoxy-6-trimethylsilylethynyl -benzothiazole Triethylamine (1.5 mL) and tetrakistriphenylphosphine palladium (95 mg) in a solution of 6-bromo-7-methoxybenzothiazole (200 mg) in acetonitrile (3 mL) Then, copper iodide (16 mg) and trimethylsilylacetylene (580 μL) were added, and the mixture was stirred at 80 ° C. for 6.5 hours. The reaction mixture was concentrated, and the residue was purified by silica gel column chromatography (ethyl acetate / hexane = 25%) to give 7-methoxy-6-trimethylsilylethynyl-benzothiazole (143 mg) as a pale brown oil.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 0.28 (s, 9 H), 4.21 (s, 3 H), 7.54 (d, J = 8.3 Hz, 1 H), 7.76 (d, J = 8.3 Hz , 1 H), 8.99 (s, 1 H)

(5) Synthesis of 6-ethynyl-7-methoxybenzothiazole To a suspension of 7-methoxy-6-trimethylsilylethynyl-benzothiazole (102.6 g) in methanol (1.0 L) was added potassium carbonate (59.7 g). And stirred at room temperature for 30 minutes. A saturated aqueous ammonium chloride solution (600 ml) and water were added, and the organic layer extracted with ethyl acetate was washed with saturated brine and dried over magnesium sulfate. The filtrate obtained by filtration was concentrated, and the residue was purified by silica gel column chromatography (ethyl acetate / chloroform = 0-2%) to give 6-ethynyl-7-methoxybenzothiazole (63.8 g) as a light brown oil. I got it.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 3.40 (s, 1 H), 4.20 (s, 3 H), 7.51-7.64 (m, 1 H), 7.74-7.85 (m, 1 H), 9.01 (s, 1 H)

(6) Synthesis of 7-methoxy-6- (4-methylthiazol-2-ylethynyl) -benzothiazole Under nitrogen atmosphere, 6-ethynyl-7-methoxybenzothiazole (29.8 g), 2-iodo-4-methyl Tetrakistriphenylphosphine palladium (10.9 g) was added to a suspension of thiazole (42.5 g) and triethylamine (300 mL) in acetonitrile (600 mL), and the mixture was stirred at 80 ° C. for 7 hours. The residue obtained by filtering the precipitate and concentrating the filtrate was subjected to column chromatography using ethyl silica gel (ethyl acetate) and then to silica gel column chromatography (ethyl acetate / chloroform / hexane = 75/0/25 to 50/25/25 to 37.5 / 25 / 37.5) to give 7-methoxy-6- (4-methylthiazol-2-ylethynyl) -benzothiazole (66.7 g) as a light brown oil Obtained.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 2.51 (d, J = 0.9 Hz, 3 H), 4.29 (s, 3 H), 6.96 (q, J = 0.9 Hz, 1 H), 7.65 (d , J = 8.3 Hz, 1 H), 7.83 (d, J = 8.3 Hz, 1 H), 9.03 (s, 1 H)

(7) Synthesis of 1- (7-methoxybenzothiazol-6-yl) -2- (4-methylthiazol-2-yl) -ethane-1,2-dione 7-methoxy-6- (4-methylthiazole To a suspension of -2-ylethynyl) -benzothiazole (600 mg) in acetone (40 mL) -buffer (20 mL) was added potassium permanganate (662 mg), and the mixture was stirred for 40 minutes. As the buffer, an aqueous solution in which sodium hydrogen carbonate (6.8 g) and anhydrous magnesium sulfate (68.4 g) were dissolved in water (3.0 l) was used. After cooling with ice, sodium nitrite (260 mg) and sulfuric acid (3 mL, 10% aqueous solution) were added and stirred for 20 minutes. Chloroform (100 mL) was added, and the mixture was filtered using Celite (registered trademark). Water was added to the filtrate, and the mixture was further extracted with chloroform. The organic layer was dried over magnesium sulfate. The filtrate obtained by filtration was concentrated, and the residue was purified by silica gel column chromatography (ethyl acetate / hexane = 50%) to give 1- (7-methoxybenzothiazol-6-yl) -2- (4-methyl Thiazol-2-yl) -ethane-1,2-dione (628 mg) was obtained as a pale yellow powder.
¹ H NMR (600 MHz, CDCl ₃ ) δ ppm: 2.49 (s, 3 H), 3.83 (s, 3 H), 7.33-7.37 (m, 1 H), 8.01 (d, J = 8.3 Hz, 1 H ), 8.23 (d, J = 8.7 Hz, 1 H), 9.17 (s, 1 H)

(8) 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazol 1- (7-methoxybenzothiazol-6-yl) -2 To a suspension of-(4-methylthiazol-2-yl) -ethane-1,2-dione (34.0 g) in tetrahydrofuran (800 mL) and methanol (400 mL) was added paraformaldehyde (34.0 g) and ammonium acetate (66 0.0 g) was added and stirred at 60 ° C. for 125 hours, paraformaldehyde (34.0 g) and ammonium acetate (66.0 g) were added, and the mixture was stirred at 60 ° C. for 68 hours. Saturated aqueous sodium hydrogen carbonate was added, extracted with chloroform, and dried over magnesium sulfate. The filtrate obtained by filtration is concentrated, and the residue is purified by silica gel column chromatography (methanol / chloroform = 0 to 10%), and then column chromatography using NH silica gel (methanol / chloroform = 0 to 2%). To obtain colorless amorphous (20.6 g). A colorless amorphous (62.2 g) obtained in the same manner was recrystallized (ethyl acetate) to give 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazole-4- Yl] -benzothiazole (42.7 g) was obtained as a colorless powder.
¹ H NMR (600 MHz, DMSO-d ₆ ) δ ppm: 2.20 (br. S., 3 H) 3.65 (s, 3 H) 7.01 (s, 1 H) 7.63 (br. S., 1 H) 7.83 (s, 1 H) 7.84 (d, J = 8.25 Hz, 1 H) 9.43 (s, 1 H) 12.72 (br. s., 1 H)

Test Example 1 Solubility Test As a test compound, 7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole synthesized in Example 1 above was used. And 6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole (hereinafter referred to as Comparative Example 1) described in WO2005 / 085241 was used. The structure of Comparative Example 1 is shown below.

1,3-butylene glycol (10 g) was weighed and placed in a graduated cylinder, EtOH (79 mL) was added and stirred to homogenize, and then water was added to a total volume of 100 mL to prepare a base. Add an excess amount of the test compound to the test tube, add the base prepared above, stir at room temperature for 24 hours, filter through a membrane filter (0.45 μm), and dilute the resulting filtrate with 50% acetonitrile / water mixture. Then, quantification was performed by HPLC, and the obtained value was defined as solubility. The solubility of Comparative Example 1 was 14.9 mg / mL, and the solubility of Example 1 was 51.8 mg / mL.

From this test, it was found that the solubility in Example 1 was significantly higher in Example 1 than in Comparative Example 1.

Test Example 2 [Skin Smad2 Phosphorylation Inhibition Test]
As test compounds, Example 1 and Comparative Example 1 were used as in Test Example 1. The back of C57BL / 6 mice was removed, and the base prepared in Test Example 1 or the test compound solution dissolved in the base was applied and administered 16 days later, and the skin was collected 1 hour and 8 hours after administration. The concentration of the test compound was 1.5% which is the maximum dissolution concentration in Comparative Example 1, and 3% in Example 1. 50 mM Tris-HCl (pH 7.6) containing 1% NP-40 and 150 mM sodium chloride was added to each skin sample, homogenized, and then centrifuged at 3,000 rpm for 15 minutes, and the supernatant was used. Western blot analysis was performed. Anti-phosphorylated Smad2 antibody or anti-Smad2 antibody as the primary antibody, HRP-labeled anti-rabbit IgG antibody as the secondary antibody, and ECL Plus Western Blotting Detection Reagents (GE Healthcare) as the detection reagent, Lumi-Imager F1 ( The amount of luminescence of phosphorylated Smad2 and Smad2 was measured using Roche Diagnostics). The test was conducted in 5 cases in each group. The phosphorylated Smad2 level was expressed as a relative value when the average value of phosphorylated Smad2 / Smad2 in the base administration group was 1.

The inhibition rate of Smad2 phosphorylation in Comparative Example 1 was 80.4% after 1 hour and 28.3% after 8 hours. Further, the result after 8 hours could not be said to significantly suppress phosphorylation of Smad2. On the other hand, the inhibition rate of Smad2 phosphorylation in Example 1 was 78.8% after 1 hour and 72.6% after 8 hours, and both significantly suppressed phosphorylation of Smad2. The results are shown in the figure.

From the above results, since Example 1 has improved solubility in the base compared to Comparative Example 1, it can be dissolved in the base at a high dose, and has a more sustained skin Smad2 phosphorylation inhibitory action. I found out.

Since the compound of the present invention has an inhibitory effect on ALK5, it blocks glomerulonephritis, diabetic nephropathy, liver fibrosis, cirrhosis, pulmonary fibrosis, proliferative vitreous retina by blocking the TGF-β / Smad signal It is useful as a prophylactic or therapeutic agent for diseases such as dermatosis, scleroderma, or alopecia, and further as a hair follicle cell growth promoter, hair growth agent, or hair restorer.

Claims

7-methoxy-6- [5- (4-methyl-thiazol-2-yl) -3H-imidazol-4-yl] -benzothiazole or a pharmaceutically acceptable salt thereof.