WO2009084497A1 - Methyl-substituted piperidine derivative - Google Patents

Abstract

Disclosed is 2-({6-[(3R)-3-amino-3-methylpiperidin-1-yl]- 1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H-pyrrolo[3,2-d]pyrimidin-5-yl}methyl)-4-fluorobenzonitrile having high DPP-IV inhibitory activity and improved safety and toxicity, or a pharmaceutically acceptable salt thereof.

Description

Methyl-substituted piperidine derivatives

The present invention relates to 2-({6-[(3R) -3-amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetra Hydro-5H-pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile (hereinafter sometimes abbreviated as compound A if necessary) or a pharmaceutically acceptable salt thereof ( Hereinafter, the compound A or a pharmaceutically acceptable salt thereof may be abbreviated as the compound of the present invention as needed). The compound of the present invention is useful as a medicine, and more specifically, is effective as a dipeptidyl peptidase-IV (DPP-IV) inhibitor. The present invention further relates to a therapeutic agent for diabetes containing the compound of the present invention as an active ingredient.

Various DPP-IV inhibitors have been reported. For example, Patent Documents 1 and 2 report that compounds having a pyrrolo [3,2-d] pyrimidine ring are effective as DPP-IV inhibitors. However, these documents do not specifically describe the compounds of the present invention.
International Publication No. 2006/068163 Pamphlet International Publication No. 2007/071738 Pamphlet

An object of the present invention is to provide a novel compound having excellent DPP-IV inhibitory activity.

As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the compound of the present invention has an excellent DPP-IV inhibitory action. Further, as will be apparent from the test examples described later, structurally similar compounds have time-dependent enhancement of metabolic reaction inhibition, that is, mechanism-based inhibition (MBI), whereas the compounds of the present invention can avoid MBI. The inventors have found that this is possible and have completed the present invention.

That is, the present invention:
[1] 2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro -5H-pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile or a pharmaceutically acceptable salt thereof,
[2] 2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro -5H-pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile,
[3] The compound according to [1] or a pharmaceutically acceptable salt thereof, or a dipeptidyl peptidase-IV inhibitor containing the compound according to [2] as an active ingredient, and [4] the compound according to [1] or The present invention relates to a therapeutic agent for diabetes containing the pharmaceutically acceptable salt or the compound described in [2] as an active ingredient.

The compound of the present invention has excellent DPP-IV inhibitory activity. A compound having DPP-IV inhibitory activity acts on blood GLP-1 as described in, for example, WO 2006/068163 pamphlet, thereby promoting insulin secretion dependent on blood glucose level, pancreatic function It has effects such as improvement, improvement of postprandial hyperglycemia, improvement of glucose tolerance, and improvement of insulin resistance, and is useful as a treatment for type 2 diabetes (non-insulin dependent diabetes) (RAPederson et al., Diabetes Vol .47, p1253-1258, 1998).

On the other hand, an irreversible inhibitory action on metabolic enzymes is called mechanism-based inhibition (MBI). The feature is that inhibition continues for a while after drug administration is discontinued. It is known that a metabolite produced by a metabolic enzyme forms a stable complex or a covalent bond with the metabolic enzyme.
The combined use of a drug having the action of MBI and a drug that is metabolized by its related enzyme increases the blood concentration of the latter drug and may cause drug interaction. Therefore, it becomes difficult to use a drug having the action of MBI, for example, its use is restricted. For example, clarithromycin metabolites have MBI action, and it has been reported that when used in combination with terfenadine, the blood concentration of terfenadine increases and causes arrhythmia.
Avoiding MBI is a very important issue in developing a drug with high therapeutic effect and high safety. For example, in Q5 of Q & A in the Pharmaceutical Examination No. 813 “Methods for Examining Drug Interactions” of the Ministry of Health, Labor and Welfare's Department of Pharmacy Review and Administration Section Q5, “If cytochrome P450 inhibition mechanism is irreversible ... In principle, it is desirable to discontinue development if there are concerns about clinically harmful interactions. However, the expected usefulness of the developed drug is If it's better than that risk, we ’ll do clinical trials. ” Also, in the FDA website “Guidance for Industry” item III (http://www.fda.gov/cber/gdlns/metabol.htm#iii), “In contrast, when positive findings arise in vitro metabolic and / or drug-drug interaction studies, clinical studies are recommended ... ”.

A shows the results of measuring the metabolic activity of the substrate substance (midazolam) after preincubation of Compound A and human liver microsomes in the presence of NADPH, and examining the influence on the metabolic activity by preincubation. B shows the results obtained in a similar test with Compound B. C shows the result obtained in the same test with Compound C. In each figure, the vertical axis represents metabolic activity (%). The horizontal axis indicates time (minutes). ○ indicates 0 μM, ● indicates 1 μM, □ indicates 5 μM, ■ indicates 10 μM, Δ indicates 20 μM, ▲ indicates 50 μM, and ◇ indicates 100 μM.

A shows the inactivation rate constant at each concentration of Compound A. B shows the inactivation rate constant at each concentration of Compound B. C represents an inactivation rate constant at each concentration of Compound C. In each figure, the vertical axis represents the inactivation rate constant (min ⁻¹ ). The horizontal axis indicates the concentration (μM) of each compound.

Hereinafter, the present invention will be described in more detail.

Compound A is a compound represented by the following formula.

Examples of the “pharmaceutically acceptable salt” include inorganic acid salts such as hydrochloride, hydrobromide, sulfate, phosphate or nitrate, or acetate, propionate, oxalate, and succinate. Organic salts such as lactate, malate, tartrate, citrate, maleate, fumarate, methanesulfonate, benzenesulfonic acid, p-toluenesulfonate or ascorbate It is done.

The present invention also includes hydrates of the compounds of the present invention or solvates such as ethanol solvates. Furthermore, the present invention also includes all tautomeric forms of the compounds of the present invention, all stereoisomers present, and crystal forms of all embodiments.

Hereinafter, the production method of the compound of the present invention will be described with reference to examples, but the present invention is not limited to these examples. In the present specification, the following abbreviations may be used for the sake of simplicity. Me: methyl group, Et: ethyl group, ^t Bu: tert-butyl group, Boc: tert-butoxycarbonyl group

The compound of the present invention can be synthesized from known compounds by combining known synthesis methods. For example, it can be synthesized according to the method described in International Publication No. 2006/068163 pamphlet. An example is shown below.

1) Step 1
Compound (1-5) can be produced by reacting compound (1-1) with compound (1-2) in an inert solvent. Examples of the inert solvent include aromatic hydrocarbon solvents such as toluene, benzene, and xylene. The reaction temperature can usually be selected from the range of about 30 ° C. to about 100 ° C.

2) Step 2
Compound (1-7) is produced by reacting compound (1-5) with compound (1-6) in the presence of an organic base in an inert solvent. Examples of the inert solvent include nitrile solvents such as acetonitrile or propionitrile. Examples of the organic base include 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU), 1,5-diazabicyclo [4.3.0] non-5-ene, or 1,4-diazabicyclo. [5.4.0] undec-7-ene and the like. The reaction temperature is usually selected from the range of about 30 ° C. to about 80 ° C., but the reaction may be performed under reflux.

3) Step 3
Compound (1-9) can be produced by reacting compound (1-7) with compound (1-8) in the presence of a base in an inert solvent. Examples of the base include alkali carbonates such as potassium carbonate, sodium carbonate, cesium carbonate, potassium hydrogen carbonate or sodium hydrogen carbonate, and preferably potassium carbonate. As the inert solvent, an aprotic solvent (N, N-dimethylformamide, dimethyl sulfoxide, etc.), an ether solvent (diethyl ether, tetrahydrofuran, 1,4-dioxane, etc.), a ketone (acetone, etc.), or a mixture thereof Solvent, and the like, and preferably N, N-dimethylformamide and the like. The reaction temperature can usually be selected from the range of about 10 ° C to about 60 ° C.

4) Step 4
Compound (1-10) can be produced by reacting compound (1-9) with a base in an inert solvent. Examples of the base include alkali amides such as lithium amide or sodium amide, or alkali hydrides such as sodium hydride or potassium hydride. Examples of the inert solvent include aromatic hydrocarbon solvents such as toluene, benzene, and xylene, hydrocarbon solvents such as hexane and heptane, tert-butyl alcohol, acetonitrile, N, N-dimethylformamide, ether solvents (diethyl). Ether, tetrahydrofuran or 1,4-dioxane), or a mixed solvent thereof. As conditions, lithium amide is preferred as the base. As the solvent, a mixed solvent of ter-butyl alcohol and acetonitrile, or a mixed solvent of ter-butyl alcohol, acetonitrile, heptane, and toluene is preferable. The reaction temperature can usually be selected from the range of about 10 ° C to about 100 ° C.

5) Step 5
Compound (1-11) is produced by reacting compound (1-10) with potassium cyanate in an inert solvent. Examples of the inert solvent include water, an organic acid such as acetic acid or propionic acid, or an aromatic hydrocarbon solvent such as toluene, benzene, or xylene. Usually, the reaction is performed in a mixed solvent of water, acetic acid, and toluene. Is done. The reaction temperature is usually selected from the range of about 20 ° C to about 80 ° C.

6) Step 6
Compound (1-12) is produced by reacting compound (1-11) with an inorganic base in an inert solvent. Examples of the inorganic base include potassium carbonate, cesium carbonate, sodium carbonate, and the like. Examples of the inert solvent include aprotic solvents (N, N-dimethylformamide, dimethylsulfoxide and the like), and the use of N, N-dimethylformamide is preferred. The reaction temperature is usually selected from the range of about 20 ° C to about 80 ° C.

7) Step 7
Compound (1-14) is produced by reacting compound (1-12) with methyl iodide in an inert solvent. Examples of the inert solvent include aprotic solvents (N, N-dimethylformamide, dimethylsulfoxide and the like), and the use of N, N-dimethylformamide is preferred. The reaction temperature is usually selected from the range of about 20 ° C to about 50 ° C. It is also possible to react by adding methyl iodide to the reaction solution in Step 6.

8) Step 8
Compound (1-15) is produced by cyanating compound (1-14) in an inert solvent in the presence of zinc cyanide and a Pd catalyst, in the presence or absence of phosphine. Examples of the inert solvent include N-methyl-2-pyrrolidone or N, N-dimethylformamide. Pd catalysts include tris (dibenzylideneacetone) dipalladium complex Pd ₂ (dba) ₃ .CHCl ₃ , bis [tri (tert-butyl) phosphine] palladium complex Pd [(tert-Bu) ₃ P] ₂ , tetrakis ( Triphenylphosphine) palladium complex Pd (PPh ₃ ) ₄ , bis (trifluoroacetoxy) palladium complex Pd (OCOCF ₃ ) ₂ can be mentioned, and phosphine includes triphenylphosphine [Ph ₃ P], tri (tert-butyl) Examples include phosphine [(tert-Bu) ₃ P], tri-o-toluylphosphine [(o-Tol) ₃ P], diphenylphosphinoferrocene [DPPf], diphenylphosphinobutane [DPPb], and the like. When Pd ₂ (dba) ₂ is used as a Pd catalyst, it is preferable to use (o-Tol) ₃ P. The reaction temperature is usually selected from the range of about 80 ° C to about 130 ° C. In addition, in this step, literature (for example, Synth. Commun. 24, 887 (1994), Organic Letters 9, 1711 (2007), Tetrahedron Lett. 40, 8193 (1999), Tetrahedron Lett. 45, 1441 (2004), etc. ) Can be referred to.

9) Step 9
As step 9, the following production method (A) and production method (B) can be used.
Production method (A): Compound A is produced by reacting compound (1-15) with benzenesulfonic acid or its monohydrate in an inert solvent, and neutralizing with an inorganic base after completion of the reaction. can do. Examples of the inorganic base include sodium hydroxide and potassium hydroxide, which are usually used as an aqueous solution. Examples of the inert solvent include alcohol solvents (ethanol, methanol, 2-propanol, etc.), and nitrile solvents (acetonitrile, propionitrile, etc.). Usually, a mixed solvent of an alcohol solvent and a nitrile solvent is used. It is done. The reaction temperature can usually be selected from the range of about 50 ° C. to about 100 ° C.
Production method (B): Compound A can be produced by reacting compound (1-15) with an inorganic acid in an inert solvent. Examples of the inert solvent include halogenated hydrocarbon solvents such as dichloromethane, 1,2-dichloroethane, and chloroform. Examples of the inorganic acid include hydrochloric acid and the like. The reaction temperature can usually be selected from the range of about −10 ° C. to about 30 ° C.

Unless otherwise specified, the raw materials and reagents used above are commercially available compounds, or can be produced from known compounds using known methods. For example, the compound (1-2) can be synthesized according to the method described in the literature (Organic® Letters® 7, 55-58® (2005)).

Further, the compound of the present invention can be synthesized as a racemate and fractionated by column chromatography using a filler bound with an optically active ligand.

The compound of the present invention can be converted into a salt by mixing with a pharmaceutically acceptable acid in a solvent such as water, methanol, ethanol, acetone or the like. Examples of pharmaceutically acceptable acids include inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid and nitric acid, or acetic acid, propionic acid, oxalic acid, succinic acid, lactic acid, malic acid, tartaric acid, citric acid, Examples of the organic acid include maleic acid, fumaric acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and ascorbic acid.

The compound of the present invention can be applied to the treatment of various diseases because of its inhibitory action on DPP-IV. The compounds described herein inhibit postprandial hyperglycemia in pre-diabetic conditions, treat non-insulin dependent diabetes, treat autoimmune diseases such as arthritis and rheumatoid arthritis, treat intestinal mucosal diseases, promote growth, transplant organs It is useful for inhibiting rejection of fragments, treating obesity, treating eating disorders, treating HIV infection, inhibiting cancer metastasis, treating benign prostatic hyperplasia, treating periodontitis, and treating osteoporosis.

The compounds of the present invention, when used therapeutically, are used as pharmaceutical compositions as oral or parenteral (eg, intravenous, subcutaneous, or intramuscular injection, topical, rectal, transdermal, or nasal Administration). Examples of compositions for oral administration include tablets, capsules, pills, granules, powders, solutions, suspensions, etc. Examples of compositions for parenteral administration include, for example, injections. Aqueous agents or oily agents, ointments, creams, lotions, aerosols, suppositories, patches and the like can be mentioned. These preparations can be prepared using conventionally known techniques, and can contain non-toxic and inert carriers or excipients usually used in the pharmaceutical field.

The dose varies depending on the individual compound and the patient's disease, age, weight, sex, symptom, route of administration, etc., but usually 0.1 to 1000 mg of the compound of the present invention for adults (weight 50 kg) / Day, preferably 1 to 300 mg / day, once a day or in 2 to 3 divided doses. It can also be administered once every few days to several weeks.

The compound of the present invention is for the purpose of enhancing its effect, and is a drug such as a therapeutic agent for diabetes, a therapeutic agent for diabetic complications, an antihyperlipidemic agent, an antihypertensive agent, an antiobesity agent, a diuretic agent (hereinafter abbreviated as a concomitant drug). Can be used in combination. The administration timing of the compound of the present invention and the concomitant drug is not limited, and these may be administered to the administration subject at the same time or may be administered with a time difference. Moreover, it is good also as a mixture of this invention compound and a concomitant drug. The dose of the concomitant drug can be appropriately selected based on the clinically used dose. The compounding ratio of the compound of the present invention and the concomitant drug can be appropriately selected depending on the administration subject, administration route, target disease, symptom, combination and the like. For example, when the administration subject is a human, the concomitant drug may be used in an amount of 0.01 to 100 parts by weight per 1 part by weight of the compound of the present invention.

Examples of diabetes therapeutic agents include insulin preparations (eg, animal insulin preparations extracted from bovine and porcine pancreas; human insulin preparations synthesized by genetic engineering using Escherichia coli and yeast), insulin resistance improving agents ( Examples, pioglitazone or its hydrochloride, troglitazone, rosiglitazone or its maleate, GI-262570, JTT-501, MCC-555, YM-440, KRP-297, CS-011, etc.), α-glucosidase inhibitor ( Examples, voglibose, acarbose, miglitol, emiglitate, etc.), biguanides (eg, metformin, etc.), insulin secretagogues (eg, tolbutamide, glibenclamide, gliclazide, chlorpropamide, tolazamide, acetohexamide, glyclopyramide, glimepiride Sulfonylurea drugs; repaglinide, senagrinide, nateglinide, mitiglinide, etc.), GLP-1, GLP-1 analogues (exenatide, liraglutide, SUN-E7001, AVE010, BIM-51077, CJC1131, etc.), protein tyrosine phosphatase inhibitors (eg, vanadine) Acid) and β3 agonists (eg, GW-427353B, N-5984, etc.).

Examples of the therapeutic agent for diabetic complications include aldose reductase inhibitors (eg, torrestat, epalrestat, zenarestat, zopolestat, minarestat, fidarestat, ranirestat, SK-860, CT-112, etc.), neurotrophic factors (eg, NGF) , NT-3, BDNF, etc.), PKC inhibitors (eg, LY-333531), AGE inhibitors (eg, ALT946, pimagedin, pyratoxatin, N-phenacylthiazolium bromide (ALT766), etc.), active oxygen elimination Examples thereof include drugs (eg, thioctic acid) and cerebral vasodilators (eg, thioprid, mexiletine, etc.). Antihyperlipidemic agents include HMG-CoA reductase inhibitors (eg, pravastatin, simvastatin, lovastatin, atorvastatin, fluvastatin, itavastatin or their sodium salts), squalene synthase inhibitors, ACAT inhibitors, etc. Can be mentioned. As an antihypertensive agent, an angiotensin converting enzyme inhibitor (eg, captopril, enalapril, alacepril, delapril, lizinopril, imidapril, benazepril, cilazapril, temocapril, trandolapril, etc.), angiotensin II antagonist (eg, olmesartan, medoxomil, candesalmil, candesalmil) Cilexetil, losartan, eprosartan, valsantan, telmisartan, irbesartan, tasosartan, etc.), calcium antagonists (eg, nicardipine hydrochloride, manidipine hydrochloride, nisoldipine, nitrendipine, nilvadipine, amlodipine, etc.), renin inhibitors (aliskiren, etc.), etc. .

Examples of anti-obesity agents include central anti-obesity agents (eg, phentermine, sibutramine, ampepramon, dexamphetamine, mazindol, SR-141716A, etc.), pancreatic lipase inhibitors (eg, orlistat, etc.), peptide anorectic agents (Eg, leptin, CNTF (ciliary neurotrophic factor), etc.), cholecystokinin agonists (eg, lynchtrypto, FPL-15849, etc.) and the like. Examples of diuretics include xanthine derivatives (eg, sodium salicylate theobromine, calcium salicylate theobromine, etc.), thiazide preparations (eg, etiazide, cyclopenthiazide, trichloromethiazide, hydrochlorothiazide, hydroflumethiazide, benchylhydrochlorothiazide, pentfurizide, polythiazide. , Methiclotiazide, etc.), anti-aldosterone preparations (eg, spironolactone, triamterene, etc.), carbonic anhydrase inhibitors (eg, acetazolamide, etc.), chlorobenzenesulfonamide preparations (eg, chlorthalidone, mefluside, indapamide, etc.), azosemide, isosorbide , Ethacrynic acid, piretanide, bumetanide, furosemide and the like.

The concomitant drug is preferably GLP-1, GLP-1 analog, α-glucosidase inhibitor, biguanide, insulin secretagogue, insulin resistance improver and the like. Two or more of the above concomitant drugs may be used in combination at an appropriate ratio.

When the compound of the present invention is used in combination with a concomitant drug, the amount of these drugs used can be reduced within a safe range considering the side effects of the drug. In particular, biguanides can be reduced from normal dosages. Therefore, side effects that may be caused by these drugs can be safely prevented. In addition, the dosage of diabetic complications, antihyperlipidemic agents, antihypertensives, etc. can be reduced, and as a result, side effects that may be caused by these agents can be effectively prevented.

EXAMPLES The present invention will be described more specifically with reference examples, examples and test examples. However, the present invention is not limited to these examples. In addition, the compound names shown in the following Reference Examples and Examples do not necessarily follow the IUPAC nomenclature.

Reference example 1
tert-butyl 3-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidin-1-yl} -2-cyano-3- (methylthio) acrylate

To a solution of tert-butyl 2-cyano-3,3-bis (methylthio) acrylate (48.43 g) in toluene (25 ml) was added (3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidine (40.23 A toluene solution (70 ml) of g) was added and stirred at 80 ° C. After 4 hours, heptane (300 ml) was added at 80 ° C. and allowed to warm to room temperature. Then, after stirring for 1 hour in an ice bath, the precipitated white solid was collected by filtration. Drying under reduced pressure gave the title compound (64.50 g) as a white solid.
MS (ESI +) 412 (M ⁺ +1, 60%)

Reference example 2
tert-Butyl 3-[(2-Bromo-5-fluorobenzyl) amino] -3-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidin-1-yl} -2- Cyanoacrylate

The compound of Reference Example 1 (70.7 g) was dissolved in acetonitrile (70 ml), DBU (52.35 g) and 2-bromo-5-fluorobenzylamine (36.22 g) were added, and the mixture was stirred at 50 ° C. After 5 hours, the mixture was diluted with toluene (200 ml) and washed with water. The obtained organic layer was washed with water, 10% aqueous potassium hydrogen sulfate solution and 10% aqueous sodium hydroxide solution, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (108.3 g) as a yellow amorphous product. Obtained.
MS (ESI +) 567 (M ⁺ +1, 60%)

Reference example 3
tert-Butyl 3-[(2-Bromo-5-fluorobenzyl) (2-ethoxy-2-oxoethyl) amino] -3-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methyl Piperidin-1-yl} -2-cyanoacrylate

The compound of Reference Example 2 (108.3 g) was dissolved in dimethylformamide (170 ml), potassium carbonate (104.8 g) was added, and the mixture was stirred at room temperature. After dropwise addition of ethyl bromoacetate (50.63 g), the mixture was stirred at 40 ° C. for 1 hour. Toluene was added and filtered through Celite, and the resulting organic layer was washed with water, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (124.10 g) as a dark red amorphous.
MS (ESI +) 653 (M ⁺ +1, 60%)

Reference example 4
4-tert-butyl 2-ethyl 3-amino-1- (2-bromo-5-fluorobenzyl) -5-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidine-1 -Il} -1H-pyrrole-2,4-dicarboxylate

Heptane (146 ml) was added to lithium amide (9.6 g), and a mixed solution of tert-butyl alcohol (268 g) and heptane (30 ml) was added dropwise at 80 ° C. After 1 hour, the mixture was cooled to 30 ° C., and acetonitrile (340 ml) was added. A toluene (350 ml) solution of the compound of Reference Example 3 (124.10 g) was added to the mixture and stirred. Two hours later, the solvent was distilled off under reduced pressure, and toluene (700 ml) and water (370 ml) were added. The mixture was adjusted to about pH 5.0 with concentrated hydrochloric acid, filtered through celite, and separated. The obtained organic layer was dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (100 g) as a dark red oily substance.
MS (ESI +) 653 (M ⁺ +1, 100%)

Reference Example 5
4-tert-butyl 2-ethyl 3-[(aminocarbonyl) amino] -1- (2-bromo-5-fluorobenzyl) -5-{(3R) -3-[(tert-butoxycarbonyl) amino]- 3-methylpiperidin-1-yl} -1H-pyrrole-2,4-dicarboxylate

To a mixture of the compound of Reference Example 4 (100 g) dissolved in acetic acid (490 ml), a solution of potassium cyanate (25 g) dissolved in water (40 g) was added dropwise at 40 ° C. and stirred. Two hours later, the temperature was returned to room temperature, diluted with toluene (700 ml), and washed three times with water (300 ml). The organic layer was washed with saturated brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (110 g) as a dark red amorphous.
MS (ESI +) 696 (M ⁺ +1, 100%)

Reference Example 6
tert-butyl 5- (2-bromo-5-fluorobenzyl) -6-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidin-1-yl} -1,3-dimethyl -2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo [3,2-d] pyrimidine-7-carboxylate

The compound of Reference Example 5 (110 g) was dissolved in dimethylformamide (290 ml), potassium carbonate (66 g) and water (2.9 ml) were added, and the mixture was stirred at 50 ° C. After 5 hours, the mixture was cooled to 30 ° C., and methyl iodide (51 g) was added dropwise and stirred. Two hours later, water (400 ml) was added, and the precipitated solid was collected by filtration. The resulting solid was slurry washed in isopropanol (700 ml) at 60 ° C. and allowed to warm to room temperature. The solid was collected by filtration and again slurried in isopropanol (400 ml) at 60 ° C. The obtained solid was dried under reduced pressure to give the title compound (54.7 g) as a white solid.
MS (ESI +) 678 (M ⁺ +1, 100%)

Reference Example 7
tert-Butyl 5- (2-cyano-5-fluorobenzyl) -6-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidin-1-yl} -1,3-dimethyl -2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo [3,2-d] pyrimidine-7-carboxylate

To the compound of Reference Example 6 (27.14 g), N-methylpyrrolidone (100 ml), tris (dibenzylideneacetone) dipalladium (1.83 g), tris (o-tolyl) phosphine (4.99 g), zinc cyanide (Zn ( CN) ₂ ) (2.90 g) was added, and vacuum degassing and nitrogen substitution were performed five times. The mixture was stirred at 120 ° C. Two hours later, the mixture was cooled to room temperature and filtered through celite. The obtained organic layer was added to a solution in which ammonia water, a saturated aqueous ammonium chloride solution and water were mixed at a ratio of 4: 4: 1 and vigorously stirred. The resulting yellow solid was collected by filtration, slurry washed in acetonitrile (20 ml) at 80 ° C. for 2 hours, stirred in an ice bath for 1 hour and then collected by filtration. The obtained solid was dried under reduced pressure to give the title compound (18.30 g) as a white solid.
MS (ESI +) 625 (M ⁺ +1, 90%).

Example 1
2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H- Pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile

tert-Butyl 5- (2-cyano-5-fluorobenzyl) -6-{(3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidin-1-yl} -1,3-dimethyl Benzenesulfonic acid in a mixture of -2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo [3,2-d] pyrimidine-7-carboxylate (18.3 g) in acetonitrile (30 ml) A solution of monohydrate (10.85 g) in ethanol (15 ml) was added dropwise at 40 ° C., followed by stirring at 80 ° C. for 2 hours. The mixture was warmed to room temperature, diluted with ethyl acetate (50 ml), and neutralized with a solution of NaOH (2.49 g) in water (50 ml). The organic layer was washed with saturated brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (11.86 g).
¹ H NMR (400 MHz, DMSO-d ₆ ) δ 7.97-8.00 (m, 1H), 7.30-7.35 (m, 1H), 6.36-6.39 (m, 1H), 5.99 (s, 1H), 5.65 (s , 2H), 3.37 (s, 3H), 3.14 (s, 3H), 2.73-2.82 (m, 2H), 2.55-2.63 (m, 2H), 1.62-1.68 (m, 1H), 1.47-1.59 (m , 1H), 1.40 (brs, 2H), 1.28-1.38 (m, 2H), 0.89 (s, 3H).
MS (ESI +) 425 (M ⁺ +1, 100%).

Example 2
2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H- Pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile hydrochloride

The compound (140 mg) obtained in the same manner as in Example 1 was dissolved in chloroform (3.0 ml), 1N hydrochloric acid ether (2.0 ml) was added and concentrated to synthesize the title compound (150 mg).
¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.17 (brs, 3H), 7.97-8.00 (m, 1H), 7.30-7.35 (m, 1H), 6.25-6.28 (m, 1H), 6.12 (s , 1H), 5.57-5.68 (m, 2H), 3.38 (s, 3H), 3.09 (s, 3H), 3.04-3.07 (m, 1H), 2.88-2.94 (m, 2H), 2.69-2.73 (m , 1H), 1.78-1.90 (m, 2H), 1.56-1.61 (m, 2H), 1.24 (s, 3H).
MS (ESI +) 425 (M ⁺ +1, 100%).

Reference Example 8
2-({6-[(3R) -3-aminopiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H-pyrrolo [3 2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile (hereinafter abbreviated as Compound B) hydrochloride

It was synthesized by the method described in Example 13 of the pamphlet of International Publication No. 2006/068163.
¹ H NMR (300 MHz, CDCl ₃ ) δ 8.50 (brs, 3H), 7.71-7.65 (m, 1H), 7.07-7.00 (m, 1H), 6.57-6.53 (m, 1H), 5.84 (d, J = 16.7 Hz, 1H), 5.73 (s, 1H), 5.64 (d, J = 16.7 Hz, 1H), 3.59-3.57 (m, 1H), 3.45 (s, 3H), 3.39-3.37 (m, 1H) , 3.33 (s, 3H), 3.16-3.09 (m, 1H), 2.70-2.68 (m, 2H), 2.08-2.06 (m, 1H), 1.80-1.78 (m, 2H), 1.60-1.58 (m, 1H).
MS (ESI +) 411 (M ⁺ +1, 100%).

Reference Example 9
2-({6-[(3R) -3-Amino-3-ethylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H- Pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile (hereinafter abbreviated as Compound C)

Tert-Butyl 5- (2-cyano-5-fluorobenzyl) -6- {synthesized from racemic 3-[(tert-butoxycarbonyl) amino] -3-ethylpiperidine in the same manner as in Reference Examples 1 to 7 3-[(tert-Butoxycarbonyl) amino] -3-ethylpiperidin-1-yl} -1,3-dimethyl-2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo [3 , 2-d] pyrimidine-7-carboxylate (1.0 g) was used to synthesize the racemic title compound (630 mg) in the same manner as in Example 1. Next, this racemate was converted into hexane / isopropanol / diethylamine = 70/30 / using CHIRALPAK (registered trademark) AD-H (manufactured by Daicel Chemical Industries, Ltd .; chiral stationary phase: amylose tris (3,5-dimethylphenyl carbamate)). The title compound (220 mg) was obtained by resolution under conditions of 0.1 (v / v).
¹ H NMR (400 MHz, DMSO-d ₆ ) δ 7.97-8.01 (m, 1H), 7.31-7.36 (m, 1H), 6.39-6.42 (m, 1H), 6.00 (s, 1H), 5.59-5.70 (m, 2H), 3.37 (s, 3H), 3.14 (s, 3H), 2.76-2.84 (m, 2H), 2.57 (s, 2H), 1.65-1.70 (m, 1H), 1.49-1.53 (m , 1H), 1.10-1.40 (m, 6H), 0.64 (t, J = 7.5 Hz, 3H).
MS (ESI +) 439 (M ⁺ +1, 100%).

Reference Example 10
(3R) -3-methyl-ethyl nipecotic acid 1/2 di-p-toluoyl-D-tartrate

A solution of sodium hexamethyldisilazane in tetrahydrofuran (1.0M, 152 ml) was slowly added dropwise to a toluene solution (100 ml) of ethyl nipecotate (20.0 g) at a temperature of -20 to -30 ° C. After stirring for 30 minutes, methyl iodide (19.4 g) was slowly added dropwise at a temperature of -20 to -30 ° C, and the temperature was slowly returned to room temperature. Water (20.8 ml) was added, and the mixture was separated and concentrated. The obtained residue was diluted with toluene and washed with water (20 ml). The extract was dried over sodium sulfate, filtered, and concentrated under reduced pressure. Ethyl acetate (125 ml) was added to the obtained oily component. To the solution, a solution of di-p-toluoyl-D-tartaric acid in ethyl acetate (60 ml) was added at 50 ° C. and stirred. After 1 hour, the resulting white solid was returned to room temperature, collected by filtration, and dried under reduced pressure to give the title compound (13.87 g).
MS (ESI +) 171 (M ⁺ +1, 100%)

Reference Example 11
(3R) -3-Methyl-Nipecotate

The compound of Reference Example 10 (13.87 g) was dissolved in water (55 ml), 10% aqueous potassium carbonate solution (55 ml) and ether (50 ml) were added and stirred. After 30 minutes, the organic layer was separated, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (4.23 g) as a yellow oily component.
MS (ESI +) 171 (M ⁺ +1, 100%)

Reference Example 12
1-Benzyl 3-ethyl (3R) -3-methylpiperidine-1,3-dicarboxylate

The compound of Reference Example 11 (4.23 g) was dissolved in tetrahydrofuran (20 ml), triethylamine (3.76 ml) was added, and the mixture was cooled in an ice bath. Benzyl chloroformate (3.55 ml) was slowly added dropwise, and the mixture was warmed to room temperature and stirred overnight. After Celite filtration, the solvent was distilled off and diluted with ethyl acetate. The organic layer was washed with water and saturated brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (7.32 g) as a yellow oily component.
MS (ESI +) 306 (M ⁺ +1, 100%)

Reference Example 13
(3R) -1-[(Benzyloxy) carbonyl] -3-methylpiperidine-3-carboxylic acid

Methanol (10 ml) and 3N aqueous sodium hydroxide solution (10 ml) were added to the compound of Reference Example 12 (7.32 g), and the mixture was stirred at 50 ° C. Three hours later, methanol was distilled off, and the pH was adjusted to 5 or less with concentrated hydrochloric acid. After extraction with ether, the organic layer was washed with water and saturated brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (5.45 g) as a yellow oily component.
MS (ESI +) 278 (M ⁺ +1, 100%)

Reference Example 14
Benzyl (3R) -3-[(tert-butoxycarbonyl) amino] -3-methylpiperidine-1-carboxylate

The compound of Reference Example 13 (5.45 g) was dissolved in toluene (30 ml), and triethylamine (2.09 g) was added. A toluene solution (20 ml) of diphenylphosphoryl azide (5.47 g) was slowly added dropwise at 90 ° C. while confirming the generation of nitrogen. After completion of dropping, the mixture was stirred at 90 ° C. for 1 hour. The mixture was returned to room temperature, washed twice with water (27 ml), dried over sodium sulfate, filtered, and concentrated under reduced pressure until the volume became about 1/3. To the resulting solution were added tert-butanol (3.7 ml) and tert-butoxypotassium (1.0 g), and the mixture was stirred at 30 ° C. Two hours later, the mixture was washed with water, saturated aqueous ammonium chloride solution and saturated brine, dried over sodium sulfate, filtered, concentrated under reduced pressure, and purified by column chromatography to give the title compound (3.62 g) as a white solid.
MS (ESI +) 349 (M ⁺ +1, 20%)

Reference Example 15
(3R) -3-[(tert-Butoxycarbonyl) amino] -3-methylpiperidine

The compound of Reference Example 14 (34.8 g) was dissolved in ethyl acetate (50 ml), 1N hydrochloric acid (0.5 ml) and 10% Pd / C (2.0 g) were added, and the mixture was stirred under hydrogen pressure (2-2.5 atm). Two hours later, the mixture was filtered through Celite, washed with 3N aqueous sodium hydroxide, water, and saturated brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the title compound (20.4 g) as a colorless oily component. It was.
MS (ESI +) 215 (M ⁺ +1, 60%)

Reference Example 16
3-[(tert-Butoxycarbonyl) amino] -3-ethylpiperidine

Benzyl 3-[(tert-butoxycarbonyl) obtained in the same manner as in Reference Example 10 (but no salt was formed with di-p-toluoyl-D-tartaric acid), 12, 13, and 14 from ethyl nipecotate The title compound (4.20 g) was obtained as a colorless oily component from amino] -3-ethylpiperidine-1-carboxylate (6.60 g) in the same manner as in Reference Example 15.
MS (ESI +) 229 (M ⁺ +1, 60%)

Test example
Test Example 1 In vitro DPP-IV Inhibitory Action Measurement Test Test substance solutions having various concentrations were prepared so that the final concentration of human plasma containing DPP IV enzyme was 10%, and added to a microassay plate. Furthermore, a substrate (Glycyl-L-Proline 4-Methylcoumaryl-7-Amide, Peptide Institute) was added to a final concentration of 50 μM, and fluorescence intensity (excitation wavelength: 380 nm, measurement wavelength) using a fluorescence plate reader at room temperature. 460 nm) was continuously measured to determine enzyme activity. The test substance concentration (IC ₅₀ value) that inhibits the enzyme activity by 50% was calculated.

Test Example 2 Mechanism-based inhibition (MBI) evaluation test for CYP3A4 Various concentrations of test compounds are added to human liver microsomes and preincubated for 15 minutes at 37 ° C. in the presence or absence of NADPH. Thereafter, the reaction solution was diluted 20 times with a mixed solution of midazolam and NADPH, which are CYP3A4 substrates, and further reacted at 37 ° C. for 5 minutes. The reaction was stopped by adding 3 times the amount of methanol, and CYP3A4 activity was evaluated by measuring the amount of metabolites (1-Hydroxy midazolam) produced using LC / MS / MS. The activity during preincubation in the absence of NADPH was used as a control, and the value obtained by dividing the decrease in activity during preincubation in the presence of NADPH by the time (15 minutes) was defined as the inactivation rate constant (kobs). At this time, the relationship between the test compound concentration (I) and kobs is expressed as kobs = kinact × I / (K′app + I). The maximum inactivation rate constant (kinact) and the apparent dissociation constant (K'app) were calculated by regression analysis using a nonlinear least square method, and the MBI intensity was determined by the value of kinact / K'app.
The obtained results are shown in FIGS. Compound B (Reference Example 8) showed concentration-dependent inactivation of CYP3A4. Inactivation of CYP3A4 was also observed in Compound C (Reference Example 9), which is a 3-ethyl substitution product of Compound B, but its strength was lower than that of Compound B. On the other hand, inactivation of Compound A (Example 1), which is a 3-methyl-substituted product, was not observed, and regression analysis to kobs = kinact × I / (K′app + I) was impossible.

NA: not applicable

From Test Examples 1 and 2, Compound B, Compound A, and Compound C differ from each other only in that the substituent on 3-aminopiperidine is a hydrogen atom, a methyl group, or an ethyl group. However, the DPP-IV inhibitory activity IC ₅₀ (nM) is higher in the compound B (0.34 nM) having a hydrogen atom and the compound A (1.6 nM) having a methyl group, and the compound C having an ethyl group as compared with these. Is very low in activity (26 nM). On the other hand, in MBI, which is very important from the viewpoint of pharmaceutical safety, it was detected in compound B (0.34 nM) having a hydrogen atom, but not in compound A (1.6 nM) having a methyl group. There wasn't. However, MBI was also detected in Compound C having an ethyl group with an extended carbon chain. From these results, it was found that Compound A having a methyl group was a particularly excellent compound in terms of DPP-IV inhibitory activity and MBI. The reason is considered that the difference in substituents in the overall structure of the compound of the present invention affects the interaction between DPP-IV and CYP3A4. However, a compound having a hydrogen atom and a compound having a methyl group are strong in terms of interaction with DPP-IV, whereas a compound having a hydrogen atom and a compound having an ethyl group are strong in interaction with CYP3A4. The fact that it is not detected in a compound having a group is completely unexpected from the conventional knowledge.

The present invention can provide a compound having DPP-IV inhibitory activity and improved in safety, toxicity and the like.
The compound of the present invention suppresses postprandial hyperglycemia in a prediabetic state, treatment of non-insulin-dependent diabetes, treatment of autoimmune diseases such as arthritis and rheumatoid arthritis, treatment of intestinal mucosal disease, growth promotion, rejection of transplanted organ fragments It is useful for suppression, obesity treatment, eating disorder treatment, HIV infection treatment, cancer metastasis inhibition, prostate hypertrophy treatment, periodontitis treatment, and osteoporosis treatment.

Claims (4)

1. 2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H- Pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile or a pharmaceutically acceptable salt thereof.
2. 2-({6-[(3R) -3-Amino-3-methylpiperidin-1-yl] -1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-5H- Pyrrolo [3,2-d] pyrimidin-5-yl} methyl) -4-fluorobenzonitrile.
3. A dipeptidyl peptidase-IV inhibitor comprising the compound according to claim 1 or a pharmaceutically acceptable salt thereof, or the compound according to claim 2 as an active ingredient.
4. A therapeutic agent for diabetes comprising the compound according to claim 1 or a pharmaceutically acceptable salt thereof, or the compound according to claim 2 as an active ingredient.

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