Novel nicotinamide compound and use therefor

Abstract

To provide a novel dry eye treatment agent that has a strong tear secretion promotion effect.SOLUTION: The present invention pertains to 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamide)phenyl]amino]nicotinamide, a salt thereof, or a solvate thereof.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to novel nicotinamide compounds that are useful as therapeutic agents for dry eye. [Background technology]

[0002] Dry eye is the most common ocular surface disease, in which a vicious cycle occurs between the tear film and epithelial layer that make up the ocular surface, causing eye discomfort and visual abnormalities, and the estimated number of patients in Japan is said to be over 20 million. In addition, the number of dry eye patients is increasing year by year due to the recent trend of living in air-conditioned rooms, working long hours at video display terminals (VDTs), and an increase in the number of people wearing contact lenses.

[0003] According to the 2017 revised DEWSII report by the Tear Film & Ocular Surface Society, dry eye is defined as "a multifactorial ocular surface disease characterized by the breakdown of the tear film integrity, with some subjective ocular symptoms, in which instability of the tear film, antiosmolarity, inflammation or damage to the ocular surface, and sensory nerve abnormalities play a pathological role," and is recognized as a multifactorial disease. In terms of etiological and pathological classification, dry eye is classified into aqueous deficient dry eye (ADDE) and evaporative dry eye (EDE) (Non-Patent Document 1).

[0004] Previously, only one drug treatment for dry eye was available in Japan: sodium hyaluronate eye drops (Hyalein (registered trademark) eye drops), and one cyclosporine eye drop (Restasis (registered trademark)) in the United States. Therefore, in addition to these drug therapies, artificial tears and other treatments were used alone or in combination to simply replenish moisture, and surgical treatments such as punctal plug insertion to close the tear drainage site and punctal occlusion were used for severe cases. In addition, autologous serum eye drops containing similar tear components were also used, although they were prepared in-house (Non-Patent Document 2).

[0005] Recently, based on the concept of changing the quality of tears, the P2Y2 receptor agonist Diquas ophthalmic solution (dicafossol sodium), which promotes the secretion of water and mucin, and the mucosta ophthalmic solution (rebamipide), which promotes mucin production, have been approved in Japan one after another, increasing the options for treatment drugs. Among them, Diquas is a dry eye treatment drug with a strong lacrimal secretion effect that acts on the P2Y2 receptors on the conjunctival epithelium and goblet cell membranes to increase the calcium concentration in the cells, thereby promoting the secretion of water and mucin (Non-Patent Document 3).

[0006] However, as dry eye is defined as a multifactorial disease, it is difficult to treat the disease caused by a variety of factors with a single drug, and there are also severe dry eye patients who cannot be adequately treated with existing drugs. Therefore, there is currently a need for the development of a dry eye treatment with a different mechanism of action and a stronger tear secretion promoting effect. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Ocul.Surf.,15,802-812(2017) [Non-Patent Document 2] Japanese Journal of Pharmacology, 135, 138-141 (2010) [Non-Patent Document 3] IOVS,42,96-100(2001) Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a new therapeutic agent for dry eye having a stronger lacrimal secretion promoting effect. [Means for solving the problem]

[0009] In view of the above circumstances, the present inventors have conducted intensive research to search for a new therapeutic agent for dry eye, and have found that a novel compound having a nicotinamide skeleton has a strong lacrimal secretion promoting effect in normal rabbits, a rabbit atropine-induced dry eye model, and a rat extraorbital lacrimal gland removal model, thereby completing the present invention.

[0010] That is, the present invention provides the following [1] to

[20] . [1] 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (Compound 1), or a salt thereof, or a solvate thereof. [2] A lacrimation promoter comprising compound 1, or a salt thereof, or a solvate thereof as an active ingredient. [3] A prophylactic and / or therapeutic agent for dry eye, comprising compound 1, or a salt thereof, or a solvate thereof as an active ingredient. [4] A pharmaceutical composition comprising compound 1, or a salt thereof, or a solvate thereof. [5] A pharmaceutical composition for promoting lacrimal secretion, comprising compound 1, or a salt thereof, or a solvate thereof. [6] A pharmaceutical composition for preventing and / or treating dry eye, comprising compound 1, or a salt thereof, or a solvate thereof. [7] A method for promoting tear secretion, comprising administering compound 1, or a salt thereof, or a solvate of either to a patient in need of treatment. [8] A method for preventing and / or treating dry eye, comprising administering compound 1, or a salt thereof, or a solvate thereof to a patient in need of treatment. [9] Use of compound 1, or a salt thereof, or a solvate thereof for the manufacture of a lacrimation promoter.

[10] Use of compound 1, or a salt thereof, or a solvate thereof for the manufacture of an agent for the prophylaxis and / or treatment of dry eye.

[11] (S)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (compound 1b), or a salt thereof, or a solvate thereof.

[12] A lacrimation promoter comprising compound 1b, or a salt thereof, or a solvate thereof as an active ingredient.

[13] A prophylactic and / or therapeutic agent for dry eye, comprising compound 1b, a salt thereof, or a solvate thereof as an active ingredient.

[14] A pharmaceutical composition comprising compound 1b, or a salt thereof, or a solvate thereof.

[15] A pharmaceutical composition for promoting lacrimal secretion, comprising compound 1b, or a salt thereof, or a solvate thereof.

[16] A pharmaceutical composition for preventing and / or treating dry eye, comprising compound 1b, or a salt thereof, or a solvate thereof.

[17] A method for promoting tear secretion, comprising administering compound 1b, or a salt thereof, or a solvate of the compound or the salt to a patient in need of such treatment.

[18] A method for preventing and / or treating dry eye, comprising administering compound 1b, or a salt thereof, or a solvate of the same to a patient in need of such treatment.

[19] Use of compound 1b, or a salt thereof, or a solvate thereof for the manufacture of a lacrimation promoter.

[20] Use of compound 1b, or a salt thereof, or a solvate thereof for the manufacture of an agent for the prophylaxis and / or treatment of dry eye. Effect of the Invention

[0011] The present invention provides a new drug useful for treating dry eye. According to the present invention, it is possible to provide a new therapeutic agent for dry eye having a strong lacrimal secretion promoting effect. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a chromatographic chart showing the optical purity of compound 1a (configuration: R-form, specific rotation: (+)-form) using a chiral column. [Diagram 2] FIG. 2 is a chromatographic chart showing the optical purity of compound 1b (configuration: S-form, specific rotation: (-) form) using a chiral column. [Diagram 3]3 shows the effect on tear secretion when Compound 1 solution or diquafosol sodium solution was instilled once in normal rabbits. The values ​​are tear volumes 1 hour after instillation, which are converted to 100% before instillation and are expressed as the average value ± standard error as the rate of increase in tear volume compared to before instillation, and * indicates a p value of less than 0.05. [Figure 4] 4 shows the effect on tear secretion when a racemic solution, a compound 1a solution, or a compound 1b solution was instilled once in normal rabbits. The values ​​are tear volumes 1 hour after instillation, which are converted to 100% before instillation and are expressed as the average value ± standard error as the rate of increase in tear volume compared to before instillation, and ** indicates a p value of less than 0.01. [Diagram 5] 5 shows the effect on tear secretion in a rabbit atropine-induced dry eye model when saline (control), 0.01% racemic solution, Compound 1a solution or Compound 1b solution, or 3% diquafosol sodium solution was instilled at 50 μL each 4 times a day for 10 days. The tear volume 1 hour after instillation was converted to 100% before instillation, and the values ​​are expressed as the average value ± standard error as the rate of increase in tear volume compared to before instillation, and * and ** indicate p values ​​less than 0.05 and 0.01, respectively. [Figure 6] 6 shows the corneal damage inhibitory effect in a rat extraorbital lacrimal gland removal dry eye model when saline (control), a 0.003% or 0.01% solution of Compound 1, or a 3% diquafosol sodium solution was administered at 5 μL six times a day for 11 days. The values ​​are expressed as the mean value of the corneal damage score ± standard error, and * and ** indicate p values ​​less than 0.05 and 0.01, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In the present invention, 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide is represented by the following formula (1):

[0014] [ka]

[0015] The compound is represented by the chemical structural formula. In the compound of formula (1), there are two optical isomers: (+)-(R)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (compound 1a) which rotates the plane of polarized light right-handed due to the presence of an asymmetric carbon, and (-)-(S)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (compound 1b) which rotates the plane of polarized light left-handed. In addition, when 1a and 1b coexist, the higher the content of 1a, the higher the specific rotation is (+), and the higher the content of 1b, the higher the specific rotation is (-). However, the present invention also includes mixtures of optical isomers having these optical rotations.

[0016] In the present invention, the term "racemate" refers to a chiral compound in a state in which two mirror image isomers (enantiomers) are present in equal amounts and thus the compound no longer exhibits optical rotation.

[0017] In the present invention, any of Compound 1 (racemate), Compound 1a (R isomer), and Compound 1b (S isomer) may be used, but from the viewpoint of the lacrimal secretion promoting effect, Compound 1b (S isomer) is more preferable.

[0018] The salt of Compound 1 is not particularly limited as long as it is a medicament acceptable salt. Examples of the salt of Compound 1 include acid addition salts, such as inorganic acid salts of hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid, phosphoric acid, etc., and organic acid salts of formic acid, acetic acid, trifluoroacetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, lactic acid, malic acid, tartaric acid, citric acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, aspartic acid, glutamic acid, etc.

[0019] Examples of solvates of Compound 1 include hydrates obtained by adding water and alcoholates obtained by adding ethanol.

[0020] Compound 1 of the present invention can be produced by various known methods, and is not particularly limited thereto. For example, as described in the Examples below, it can be produced according to the following reaction scheme.

[0021] [ka]

[0022] [In the above reaction scheme, X 1 and X 2 represents a halogen atom, and P represents a protecting group for an amino group.

[0023] Step 1 is a process for producing compound (4) from pyridine derivative (2) and amine derivative (3). X in pyridine derivative (2) 1 and X 2 represents a halogen atom such as fluorine, chlorine, bromine, or iodine, and chlorine is particularly preferred. This reaction can be carried out without a solvent, or in an organic solvent such as alcohols such as methanol, ethanol, or 2-propanol, ethers such as diethyl ether, tetrahydrofuran, or 1,4-dioxane, aromatic hydrocarbons such as benzene, toluene, or xylene, halogenated hydrocarbons such as dichloromethane, chloroform, or 1,2-dichloroethane, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, or ethyl acetate, and it is preferable to use no solvent or alcohols as a solvent. In addition, if necessary, the reaction can be carried out in the presence of an organic base such as triethylamine, tributylamine, N,N-dimethylaniline, N,N-diisopropylethylamine, pyridine, or N,N-dimethylaminopyridine, or an inorganic base such as potassium carbonate, sodium carbonate, sodium hydrogencarbonate, or sodium hydroxide. The ratio of the raw materials is preferably 0.5 to 10 moles, more preferably 0.5 to 2 moles, of the amine derivative (3) per mole of the pyrimidine derivative (2). The reaction temperature is preferably 0 to 300° C., more preferably 0 to 150° C., and the reaction time is preferably 1 to 24 hours, more preferably 2 to 6 hours.

[0024] Step 2 is a step of producing compound (6) from compound (4) and aniline derivative (5) under acidic conditions. This reaction can be carried out without a solvent or in an organic solvent such as alcohols such as methanol, ethanol, or 2-propanol, ethers such as diethyl ether, diphenyl ether, tetrahydrofuran, or 1,4-dioxane, aromatic hydrocarbons such as benzene, toluene, or xylene, halogenated hydrocarbons such as dichloromethane, chloroform, or 1,2-dichloroethane, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, acetonitrile, or ethyl acetate, and it is preferable to use ethers such as diphenyl ether as a solvent. As the acid catalyst, inorganic acids such as hydrochloric acid and sulfuric acid, or organic acids such as methanesulfonic acid and benzenesulfonic acid can be used. The raw material ratio is preferably 0.5 to 10 moles, more preferably 0.5 to 3 moles, of aniline derivative (5) per mole of compound (4). The amount of the acid is preferably 0.1 to 10 mol, more preferably 0.5 to 3 mol, per 1 mol of compound (1). The reaction temperature is preferably 100 to 200° C., more preferably 150 to 200° C., and the reaction time is preferably 5 minutes to 8 hours, more preferably 10 minutes to 2 hours.

[0025] Step 3 is a step of producing compound (8) from compound (6) and piperidine derivative (7). The condensation reagent used is not particularly limited, but examples thereof include N,N'-dicyclohexylcarbodiimide (DCC), 1-ethyl-3-(3'-dimethylaminopropyl)carbodiimide hydrochloride (WSC·HCl), 2-(7-aza-1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HATU), 1,1'-carbonyldiimidazole (CDI), diphenylphosphoryl azide (DPPA), phosphorus oxychloride / pyridine, triphenylphosphine / N-bromosuccinimide, and the like. In some cases, additives such as N-hydroxysuccinimide (HONSu), 1-hydroxybenzotriazole hydrate (HOBt·HO), and the like can be further used. A preferred combination of the condensing agent and additive used in this step is 1-ethyl-3-(3'-dimethylaminopropyl)carbodiimide hydrochloride (WSC·HCl) and 1-hydroxybenzotriazole hydrate (HOBt·H2O). In order to accelerate the reaction, a non-nucleophilic base such as triethylamine, N,N-diisopropylethylamine, or diazabicycloundecene may be added. The solvent used is not particularly limited, and examples thereof include organic solvents such as N,N-dimethylformamide, tetrahydrofuran, dioxane, cyclopentyl methyl ether, dichloromethane, and dichloroethane, and is preferably N,N-dimethylformamide. The ratio of the raw materials is preferably 0.5 to 10 moles, more preferably 0.5 to 3 moles, of piperidine derivative (7) per mole of compound (6). The amount of the condensing reagent used is preferably 0.1 to 10 moles, more preferably 0.5 to 5 moles, per mole of compound (6). The reaction temperature is preferably −30 to 150° C., more preferably 0 to 100° C. The reaction time is preferably 1 minute to 48 hours, more preferably 30 minutes to 24 hours.

[0026] Step 4 is a step of producing compound (1) by carrying out a deprotection reaction of the amino group of compound (8). The method and conditions for deprotection vary depending on the type of protecting group P. For example, benzyl and benzyloxycarbonyl groups can be deprotected by catalytic hydrogenation, and t-butoxycarbonyl groups can be deprotected by acid, and these methods can be performed with reference to methods commonly used in organic chemistry (e.g., the method described in Protective Groups in Organic Synthesis Third Edition, John Wiley & Sons, Inc., 1999).

[0027] As shown in the Examples below, compound 1, or a salt thereof, or a solvate thereof exhibits an excellent lacrimal secretion promoting effect in normal rabbits and a rabbit atropine-induced dry eye model. It also exhibits an excellent corneal damage suppressing effect in a rat extraorbital lacrimal gland removal dry eye model. Furthermore, these effects are significantly superior to those of diquafosol sodium. Therefore, compound 1, or a salt thereof, or a solvate thereof is useful as a lacrimation promoter and an agent for preventing and / or treating dry eye.

[0028] In the present invention, the term "dry eye" includes keratoconjunctivitis sicca, and also includes both types of dry eye, namely, hypolacrimation type and hyperevaporation type. Hypolacrimation type dry eye is classified into dry eye associated with Sjogren's syndrome and non-Sjogren's syndrome type dry eye. Non-Sjogren's syndrome type dry eye includes dry eye associated with lacrimal gland diseases such as congenital alacrimal gland disease, sarcoidosis, and graft-versus-host disease due to bone marrow transplantation; dry eye associated with lacrimal obstruction caused by ocular pemphigoid, Stevens-Johnson syndrome, and trachoma; dry eye associated with reduced reflex secretion caused by diabetes, corneal refractive surgery, and the like. Hyperevaporation type dry eye includes dry eye associated with reduced oil layer caused by meibomian gland dysfunction, blepharitis, and the like; dry eye associated with insufficient blinking or insufficient eyelid closure caused by exophthalmos, lagophthalmos, and the like; dry eye associated with reduced tear stability due to contact lens wear; dry eye associated with reduced mucin secretion from germ cells; dry eye associated with VDT work, and the like.

[0029] The pharmaceutical composition of the present invention contains Compound 1, a salt thereof, or a solvate thereof. It may be used alone, but is usually used in combination with a medicament-acceptable carrier, additive, etc. The administration form of the pharmaceutical composition is not particularly limited and can be appropriately selected according to the purpose of treatment. For example, it may be any of oral agents, injections, suppositories, ointments, inhalants, eye drops, nasal drops, patches, etc. Pharmaceutical compositions suitable for these administration forms can be manufactured by known formulation methods.

[0030] When preparing a solid preparation for oral administration, an excipient, and further, if necessary, a binder, a disintegrant, a lubricant, a colorant, a flavoring agent, a fragrance, etc. are added to compound 1, and then tablets, coated tablets, granules, powders, capsules, etc. can be produced by a conventional method. The additives may be those generally used in the field. For example, the excipients include lactose, sucrose, sodium chloride, glucose, starch, calcium carbonate, kaolin, microcrystalline cellulose, silicic acid, etc. Binders include water, ethanol, propanol, simple syrup, glucose solution, starch solution, gelatin solution, carboxymethylcellulose, hydroxypropylcellulose, hydroxypropyl starch, methylcellulose, ethylcellulose, shellac, calcium phosphate, polyvinylpyrrolidone, etc. Disintegrants include dry starch, sodium alginate, agar powder, sodium bicarbonate, calcium carbonate, sodium lauryl sulfate, monoglyceride stearate, lactose, etc. Lubricants include purified talc, stearates, borax, polyethylene glycol, etc. Flavoring agents include sucrose, orange peel, citric acid, tartaric acid, etc.

[0031] When preparing oral liquid preparations, oral liquid preparations, syrups, elixirs, etc. can be produced by a conventional method by adding flavoring agents, buffering agents, stabilizers, odorants, etc. to Compound 1. The flavoring agents may be those listed above, and examples of buffering agents include sodium citrate, etc., and examples of stabilizers include tragacanth, gum arabic, gelatin, etc.

[0032] When preparing an injection, a pH adjusting agent, a buffering agent, a stabilizer, an isotonicity agent, a local anesthetic agent, etc. are added to compound 1, and subcutaneous, intramuscular, and intravenous injections can be produced by a conventional method. Examples of pH adjusting agents and buffering agents include sodium citrate, sodium acetate, and sodium phosphate. Examples of stabilizers include sodium pyrosulfite, sodium edetate, thioglycolic acid, and thiolactic acid. Examples of local anesthetic agents include procaine hydrochloride and lidocaine hydrochloride. Examples of isotonicity agents include sodium chloride and glucose.

[0033] When preparing suppositories, known suppository carriers such as polyethylene glycol, lanolin, cacao butter, fatty acid triglycerides, etc., and if necessary, surfactants such as Tween (registered trademark), etc. can be added to Compound 1, and then the suppositories can be produced by a conventional method.

[0034] The eye drops may be any of aqueous eye drops, non-aqueous eye drops, suspension eye drops, emulsion eye drops, eye ointments, etc. Such preparations can be prepared as compositions suitable for the administration form by blending pharma- ceutically acceptable carriers, such as isotonicity agents, chelating agents, stabilizers, pH regulators, preservatives, antioxidants, solubilizers, thickeners, etc., as necessary, and by a (formulation) method known to those skilled in the art. When preparing eye drops, for example, the desired components are dissolved or suspended in an aqueous solvent such as sterilized purified water or saline, or in a non-aqueous solvent such as vegetable oils such as cottonseed oil, soybean oil, sesame oil, and peanut oil, and the osmotic pressure is adjusted to a predetermined level, followed by sterilization such as filtration sterilization. When preparing eye ointments, in addition to the various components described above, an ointment base can be included. The ointment base is not particularly limited, but preferred examples thereof include oil-based bases such as petrolatum, liquid paraffin, and polyethylene; emulsion bases in which an oil phase and an aqueous phase are emulsified with a surfactant or the like; and water-soluble bases such as hydroxypropylmethylcellulose, carboxymethylcellulose, and polyethylene glycol.

[0035] It can also be used as a preparation for an intraocular implant. The preparation for an intraocular implant can be prepared using a biodegradable polymer, such as a biodegradable polymer like polylactic acid, polyglycolic acid, lactic acid-glycolic acid copolymer, hydroxypropyl cellulose, and the like.

[0036] When compound 1, or a salt or solvate thereof is used for the prevention or treatment of dry eye, when an eye drop or eye ointment is selected as the dosage form, it can be administered topically to the eye in 1 to 10 times a day, preferably 1 to 8 times a day, more preferably 2 to 6 times a day. The dosage varies depending on the patient's body weight, age, gender, symptoms, dosage form, and frequency of administration, etc. Usually, for adults, as compound 1, it is in the range of 0.025 to 10000 μg per day, preferably 0.025 to 2000 μg, more preferably 0.1 to 2000 μg.

Example

[0037] Hereinafter, the present invention will be described in more detail with examples, but these examples do not limit the present invention. The optical purity of the compound was determined by HPLC. The specific rotation of the compound was measured under the following conditions. <HPLC Conditions> Detector: Ultraviolet absorptiometer (measurement wavelength: 254 nm) Column: CHIRALPAK IE (Daicel) Inner diameter 4.6 mm, length 150 mm, particle size 5 μm Column temperature: 40 °C Mobile phase: 0.1% isopropylamine in methanol Flow rate: 1.0 mL / min Injection volume: 5 μL Sample: 0.5 mg / mL (diluted with methanol) <Specific Rotation> Polarimeter: JASCO Corporation P-2200 Specific rotation [α]20D (20 °C, D line of sodium 589 nm)

[0038] Example 1 Preparation of 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (Compound 1) (Step 1) Preparation of 6-chloro-4-[(3,5-difluorobenzyl)amino]nicotinamide

[0039] [ka]

[0040] 28.7 g of 4,6-dichloropyridine-3-carboxamide synthesized according to the method described in US2006 / 0217417 was dissolved in 130 mL of ethanol, 22.8 g of 3,5-difluorobenzylamine and 52.4 mL of N,N-diisopropylethylamine were added, and the mixture was heated under reflux at 80° C. for 24 hours. After cooling to room temperature, water was added, and the precipitated crystals were collected by filtration, washed with water and hexane, and air-dried to obtain 38.9 g (87%) of 6-chloro-4-[(3,5-difluorobenzyl)amino]nicotinamide as white crystals.

[0041] 1H-NMR(400MHz, CDCl3)δ: 4.43 (2H, d, J = 5.8 Hz), 5.86 (2H, br), 6.42 (1H, s), 6.75 (1H, dddd, J = 7.7,.7.7, 2.3, 2.3 Hz), 6.80-6.87 (1H, m), 8.32 (1H, s), 9.02 (1H, br).

[0042] (Step 2) Preparation of 6-[(3-aminophenyl)amino]-4-[(3,5-difluorobenzyl)amino]nicotinamide

[0043] [ka]

[0044] 6-Chloro-4-[(3,5-difluorobenzyl)amino]nicotinamide (12.0 g) obtained in step 1, 1,3-phenylenediamine (10.9 g), and 1-butyl-3-methyl-1H-3-imidazolium chloride (14.1 g) were added to diphenyl ether (6.9 g). Methanesulfonic acid (7.85 mL) was added to this mixture, and the mixture was stirred in a bath at 170° C. for 30 minutes. After cooling, the reaction mixture was washed three times with heptane, and 7N ammonia-methanol (35 mL) was added to the residue. After the precipitate was crushed, chloroform (20 mL), water (20 mL), and saturated aqueous sodium bicarbonate solution (10 mL) were added to the mixture, and the mixture was stirred. The precipitated crystals were collected by filtration and dried to obtain 14.6 g (98%) of 6-[(3-aminophenyl)amino]-4-[(3,5-difluorobenzyl)amino]nicotinamide.

[0045] 1H-NMR (DMSO-d6) δ:9.03 (t, 1 H), 8.57 (s, 1 H), 8.36 (s, 1 H), 7.77 (br., 2 H), 7.12 (tt, 1 H), 7.00 (br d, 2 H), 6.80 (t, 1 H), 6.73 (s, 1 H), 6.50 (d, 1 H), 6.12 (d, 1 H), 5 80 (s, 1 H), 4.91 (s, 2 H), 4.41 (d, 2 H).

[0046] (Step 3) Preparation of tert-butyl 3-[[3-[[5-carbamoyl-4-[(3,5-difluorobenzyl)amino]pyridin-2-yl]amino]phenyl]carbamoyl]piperidine-1-carboxylate

[0047] [ka]

[0048] 6-[(3-aminophenyl)amino]-4-[(3,5-difluorobenzyl)amino]nicotinamide (1.00 g) obtained in step 2 and N-(tert-butoxycarbonyl)piperidine-3-carboxylic acid (0.93 g) were dissolved in N,N-dimethylformamide (4.5 mL). To this solution stirred in an ice bath, N,N-diisopropylethylamine (1.18 mL), 1-hydroxybenzotriazole hydrate (0.83 g) and 1-ethyl-3-(3'-dimethylaminopropyl)carbodiimide hydrochloride (0.83 g) were added. After removing the ice bath, the mixture was stirred at room temperature for 12 hours. Ethyl acetate (20 mL) and water (10 mL) were added, and the mixture was stirred, after which the organic layer and the aqueous layer were separated. The aqueous layer was extracted twice with ethyl acetate (15 mL). The organic layers were combined, washed with water, saturated aqueous sodium bicarbonate solution, and saturated saline, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methanol-dichloromethane), and the obtained fraction was crystallized from ethyl acetate and heptane to obtain 1.22 g (78%) of tert-butyl 3-[[3-[[5-carbamoyl-4-[(3,5-difluorobenzyl)amino]pyridin-2-yl]amino]phenyl]carbamoyl]piperidine-1-carboxylate.

[0049] (Step 4) Preparation of 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide

[0050] [ka]

[0051] Tert-butyl 3-[[3-[[5-carbamoyl-4-[(3,5-difluorobenzyl)amino]pyridin-2-yl]amino]phenyl]carbamoyl]piperidine-1-carboxylate (1.22 g) obtained in step 3 was dissolved in dichloromethane (6.7 mL). Trifluoroacetic acid (1.62 mL) was added to this solution and stirred at room temperature for 12 hours. The reaction mixture was concentrated under reduced pressure, and methanol was added to the residue, and then it was concentrated under reduced pressure again. The residue was purified by silica gel column chromatography (methanol-dichloromethane, ammonia-methanol-dichloromethane), and the obtained solid (607 mg) was crystallized from ethanol and water to obtain 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide 362 mg (36%).

[0052] 1H-NMR (DMSO-d6) δ:9.88 (s, 1 H), 9.05 (t, 1 H), 8.86 (s, 1 H), 8.39 (s, 1 H), 7.83 (br s, 2 H), 6.95-7.20 (m, 7 H), 5.86 (s, 1 H), 4.44 (d, 2 H), 3.00 (m, 1 H), 2.83 (m, 1 H), 2.40-2.65 (m, 3 H), 2.15 (br s, 1 H), 1.84 (m, 1 H), 1.59 (m, 2 H), 1.35 (m, 1 H).

[0053] Example 2 Preparation of (R)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (1a) In step 3 of Example 1, N-(tert-butoxycarbonyl)piperidine-3-carboxylic acid was changed to (R)-N-(tert-butoxycarbonyl)piperidine-3-carboxylic acid, and the same procedure was applied to give ((R)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide.

[0054] [ka]

[0055] Optical purity: 98.5%ee Specific rotation [α] 20 D : +14.4

[0056] Example 3 Preparation of (S)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide (1b) In step 3 of Example 1, N-(tert-butoxycarbonyl)piperidine-3-carboxylic acid was changed to (S)-N-(tert-butoxycarbonyl)piperidine-3-carboxylic acid, and the same procedure was applied to give (S)-4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide.

[0057] [ka]

[0058] Optical purity: 98.8%ee Specific rotation [α] 20 D :-14.3

[0059] Test Example 1: Effect on tear secretion in normal rabbits 1. Preparation of test compound solutions A. Preparation of Compound 1 Solution A predetermined amount of Compound 1 was dissolved in physiological saline, and the pH was adjusted to 5.5 with HCl or NaOH to prepare a Compound 1 solution of a desired concentration. B. Preparation of Diquafosol Sodium Solution The diquafosol sodium solution used was Diquas (registered trademark) ophthalmic solution 3% (Santen Pharmaceutical Co., Ltd.).

[0060] 2. Test Method A. Drugs and Animals Used in the Study Compound 1 solution: 0.001% solution, 0.01% solution (amount dropped: 50 μL) Diquafosol sodium solution: 3% solution (eye drop amount: 50 μL) Experimental animals: JW white rabbits (sex: weight approx. 2 kg, male, 3-4 rabbits per group) B. Methods for measuring, instilling and evaluating tears Schirmer test strips were inserted into the lower eyelids of normal JW male white rabbits, and the length of wetness was measured for 5 minutes. 50 μL of 0.001% or 0.01% Compound 1 solution or 3% diquafosol sodium solution was instilled, and 1 hour after instillation, Schirmer test strips were inserted into the lower eyelids again, and the length of wetness was measured for 5 minutes. Instillation and evaluation were performed on both eyes, and the data from each eye was treated as one example. The obtained values ​​were converted to 100% before instillation and shown as the tear increase rate compared to before instillation. Statistical analysis was performed using Student's t-test.

[0061] 3. Results and Discussion The tear production increase rate 1 hour after instillation of the test compound solution compared to before instillation is shown in Figure 3. Compound 1 solutions of 0.001% and 0.01%, and 3% diquafosol sodium solution showed tear production increase rates of 131%, 168%, and 169%, respectively, and Compound 1 solutions of concentrations of 0.01% or more and 3% diquafosol sodium solution showed significant differences compared to before instillation.

[0062] Test Example 2 Effects of the racemate and optical isomers on tear secretion in normal rabbits The effects of the racemate and the optical isomers 1a and 1b on tear secretion were compared.

[0063] 1. Preparation of Test Compound Solutions A. Preparation of Compound 1a Solution A predetermined amount of compound 1a was dissolved in physiological saline, and the pH was adjusted to 5.5 with HCl or NaOH to prepare a compound 1a solution of a desired concentration. B. Preparation of Compound 1b Solution A predetermined amount of compound 1b was dissolved in physiological saline, and the pH was adjusted to 5.5 with HCl or NaOH to prepare a compound 1b solution of a desired concentration.

[0064] 2. Test Method A. Drugs and Animals Used in the Study Racemic solution: 0.003% solution (amount to be dropped: 50 μL) Compound 1a solution: 0.003% solution (amount dropped: 50 μL) Compound 1b solution: 0.003% solution (amount dropped: 50 μL) Experimental animals: JW white rabbits (sex: weight approx. 2 kg, male, group of 8)

[0065] B. Methods for measuring, instilling and evaluating tears Schirmer test strips were inserted into the lower eyelids of normal JW male white rabbits, and the length of wetness was measured for 5 minutes. 50 μL of 0.003% racemic solution, compound 1a solution, or compound 1b solution was instilled, and 1 hour after instillation, Schirmer test strips were inserted into the lower eyelids again, and the length of wetness was measured for 5 minutes. Instillation and evaluation were performed on both eyes, and data from each eye was treated as one example. The obtained values ​​were converted to 100% before instillation and shown as the tear increase rate compared to before instillation. Statistical analysis was performed using Student's t-test.

[0066] 3. Results and Discussion The tear production increase rate 1 hour after instillation of the test compound solution compared to before instillation is shown in Figure 4. The 0.003% racemic solution, compound 1a solution, and compound 1b solution showed 129%, 124%, and 143% tear production increase rates, respectively, and significant differences were observed compared to before instillation. On the other hand, the tear production increase rate of compound 1b solution compared to before instillation was higher than that of compound 1a solution.

[0067] Test Example 3: Effect on tear secretion using an atropine-induced dry eye model The effect of increasing tear secretion when a test compound solution was instilled was examined using an atropine-induced dry eye model (Acta Pharm. 58; 163-173 (2008)), which has been reported as a dry eye model.

[0068] 1. Test Method A. Drugs and Animals Used in the Study Racemic solution: 0.003% solution (amount to be dropped: 50 μL) Compound 1a solution: 0.003% solution (amount dropped: 50 μL) Compound 1b solution: 0.003% solution (amount dropped: 50 μL) Diquafosol sodium solution: 3% solution (eye drop amount: 50 μL) Experimental animals: JW white rabbits (sex: weight approx. 2 kg, male, 3-4 rabbits per group)

[0069] B. Methods for measuring, instilling and evaluating tears 0.1% atropine sulfate was instilled into the eyes of male white rabbits of JW lineage three times a day for seven days at 50 μL, and the wetted length was measured using Schirmer's test paper for 5 minutes. Then, 0.1% atropine sulfate was instilled into the eyes three times a day, as well as physiological saline (control), 0.01% racemic solution, compound 1a solution or compound 1b solution, or 3% diquafosol sodium solution at 50 μL each four times a day for 10 days, and the wetted length was measured using Schirmer's test paper for 5 minutes one hour after the final instillation. Instillation and evaluation were performed on both eyes, and the data of each eye was treated as one example. The obtained values ​​were converted to the value before instillation of the test compound solution as 100%, and shown as the tear increase rate. Statistical analysis was performed using Student's t-test.

[0070] 2. Results and Discussion The increase in tear volume 1 hour after instillation of the test compound solution compared to before instillation is shown in Figure 5. The control, 0.01% racemic solution, compound 1a solution, and compound 1b solution showed an increase in tear volume of 86%, 151%, 157%, and 145%, respectively, which were significantly different from the control. On the other hand, the 3% diquafosol sodium solution showed an increase in tear volume of 134%, but no significant difference was observed.

[0071] Test Example 4: Effect on corneal epithelium damage in a rat extraorbital lacrimal gland removal dry eye model The inhibitory effect on corneal epithelium damage when a test compound solution was instilled was examined using a rat extraorbital lacrimal gland excision dry eye model, which has been reported as a dry eye model.

[0072] 1. Test Method A. Drugs and Animals Used in the Study Compound 1 solution: 0.003% solution, 0.01% solution (amount dropped: 5 μL) Diquafosol sodium solution: 3% solution (eye drop amount: 5 μL) Experimental animals: SD rats (sex: 6 weeks old, male, 5 rats per group) B. Methods for measuring, instilling and evaluating tears Both extraorbital lacrimal glands were removed from SD male rats under anesthesia by intraperitoneal administration of 40 mg / kg pentobarbital sodium and 10 mg / kg xylazine. From the day after removal, saline (control), 0.003% or 0.01% compound 1 solution, or 3% diquafosol sodium solution was instilled in the eyes 6 times a day at 5 μL each for 11 days. 24 hours after the final instillation, corneal damage sites were stained by instilling 2 μL of 0.1% fluorescein isothiocyanate solution under anesthesia by intraperitoneal administration of 40 mg / kg pentobarbital sodium and 10 mg / kg xylazine, and the stained images of each site divided into 9 parts of the cornea were scored into 4 levels, and the sum of the scores of the 9 sites was used as the corneal damage score for each eye. The criteria for each score are as follows. 0: Unstained 1: Staining is sparse, with each spot of staining separated 2: Moderate staining, with some punctate staining areas adjacent to each other 3: Dense staining, with each spot of staining adjacent to the others Instillation and evaluation were performed on both eyes, and data from each eye were treated as one example. Statistical analysis was performed using Dunnett's multiple comparison test.

[0073] 2. Results and Discussion The corneal damage scores 1 hour after instillation of the test compound solutions compared to those before instillation are shown in Figure 6. The control showed a corneal damage score of 18.0, the 0.003% and 0.01% compound 1 solutions showed 13.0 and 10.5, respectively, and the 3% diquafosol sodium solution showed 11.9, indicating that the 0.01% compound 1 solution and the 3% diquafosol sodium solution showed significant differences compared to the control. [Industrial Applicability]

[0074] The compound of the present invention has a significant lacrimation promoting effect and is useful as a new therapeutic agent for dry eye, and therefore has industrial applicability.

Claims

1. 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide, a salt thereof, or a solvate thereof.

2. A lacrimation promoter comprising 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide, or a salt thereof, or a solvate thereof as an active ingredient.

3. A preventive and / or therapeutic agent for dry eye, comprising 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide, or a salt thereof, or a solvate thereof as an active ingredient.

4. A pharmaceutical composition comprising 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide, or a salt thereof, or a solvate thereof.

5. A pharmaceutical composition for promoting tear secretion, comprising 4-[(3,5-difluorobenzyl)amino]-6-[[3-(piperidine-3-carboxamido)phenyl]amino]nicotinamide, or a salt thereof, or a solvate thereof.

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