KR20110097448A - A composition containing of novel imidazole pyrazine compound having influenza virus activity for treating antivirus - Google Patents

Abstract

The present invention relates to a novel imidazole pyrazine derivative (Formula 1) compound having an inhibitory activity against influenza A virus, a preparation method thereof and an antiviral composition comprising the same. Since the compounds according to the invention show a strong inhibitory activity against the flu virus, compositions containing them can be used as medicaments for the treatment of antiviral:
<Formula 1>

Description

A novel imidazole pyrazine derivative compound or a pharmaceutically acceptable salt thereof, a method for preparing the same, and a pharmaceutical composition for treating the antiviral containing the same as an active ingredient.

The present invention relates to an imidazole pyrazine derivative useful as an antiviral agent, and more particularly, to a novel imidazole pyrazine derivative compound or a pharmaceutically acceptable salt thereof, a preparation method thereof, and an antiviral therapeutic pharmaceutical containing the same as an active ingredient. To a red composition.

Between 250 and 500 million people are infected with influenza viruses each year (WHO Consultation on Priority Public Health Interventions before and during An Influenza Pandemic. 2004). Influenza viruses are RNA-dependent-RNA viruses and belong to a strain of the Orthomyxoviridae family with a single stranded RNA genome.

 The Orthomyxoviridae family is divided into five types, including influenza A, B, C viruses, Thogotovirus, and Isavirus. Influenza A, B, and C type are classified by M1 (matrix protein) and NP (nucleoprotein), and influenza A virus is classified by surface proteins HA (hemagglutinin) and NA (neuraminidase). Currently, there are 16 HA types and 9 NA types to distinguish subtypes. Recently, chemotherapy for influenza viruses has been used more effectively than vaccines (Archives of Virology 145 (2000) 2233-2248). However, chemotherapy has limited drug resistance to strains (The Pediatric infectious disease journal 27, (2008)).

In order to overcome the resistance of these drugs, the need for effective new drug development is emerging. Influenza treatments in the current situation include M2 ion channel inhibitors such as amantadine and rimantadine, NA inhibitors such as zanamivir and oseltamivir, ribavirin and cells. septeu (CellCept ^T) may be an IMPDH inhibitor, such as for example ^M (Nature Reviews Drug Discovery 5 (2006 ) 1015-1025).

M2 inhibitors, such as amantadine and rimantadine, effectively block M2 ion channels and exhibit antiviral effects, but have a narrow activity spectrum and limited resistance (Journal of Medical Virology 80 ( 2008) 895-901). NA inhibitors, such as zanamivir (Relenza) and oseltamivir (Tamiflu), have been shown to have very good antiviral activity by inhibiting neuraminidase. (Canadian Journal of Infectious Diseases and Medical Microbiology 17 (2006) 273-284). Ribavirin, also known as IMPDH inhibitor, has excellent antiviral, anticancer and immunosuppressive activity. IMPDH is an enzyme that nicotinamide adenine dinucleotide (NAD +) acts as a cofactor to convert inosine acid (IMP) to xanthosine (XMP) (A Major Therapeutic Target 2003, Medicinal Research Reviews 28 (2008) 219-232.).

Ribavirin has an IMP substrate mimic casting and shows activity of ki = 250 nM. MPA is an active metabolite of CellCept ™ (mycophenolate mofetil), a drug approved for renal or cardiac transplantation, and has an ICPDH activity of IC ₅₀ = 20 nM. VX-4979 (merimepodib), developed by Vertex as an IMPDH inhibitor, is a drug developed by structure-based drug design (Antimicrobial Agents and Chemotherapy 44 (2000) 859-866). Current side effects have been shown in the clinical process (International Journal of Cell Cloning 8 (1990) 161-170), and thiazofurin also has serious side effects.

Therefore, there is an urgent need for the development of new drugs having antiviral activity without side effects.

To develop new drugs, structure-based drug design methods were introduced, MPA (Cell 85 (1996) 921-930.), Ribavirin monophosphate (Antivir. Res, 1999), IMP mimetics (Proceedings of the National) X-ray crystal complexes, including the Academy of Sciences of the United States of America 96, 1999, 3531-3536), can be used to effectively optimize drug efficacy through structure-based drug design.

As described above, the present inventors have attempted to synthesize and develop derivatives showing potent activity against influenza virus by introducing various substituents based on imidazolpyrazine derivatives, which are completely different from IMPDH inhibitors. Thus, the newly prepared novel imidazole pyrazine derivative compound exhibits a strong inhibitory activity against influenza virus, so that the compounds of the present invention have high development potential as antiviral therapeutic agents, and have completed the present invention.

It is an object of the present invention to provide an imidazole pyrazine derivative compound exhibiting potent inhibitory activity against influenza virus, a preparation method thereof and a pharmaceutical composition for antiviral treatment containing the same as an active ingredient.

In order to achieve the above object, the present invention provides a novel imidazole pyrazine derivative represented by the following formula (1) or a pharmaceutically acceptable salt thereof, a preparation method thereof, and an antiviral pharmaceutical composition comprising the compound as an active ingredient. do.

[Formula 1]

In Chemical Formula 1,

n is an integer from 0 to 4,

R 1 is a C ₁ to C ₄ straight or crushed alkyl group, C ₅ to C ₁₀ Cycloalkyl, C ₅ to C ₁₀ 5 to 10 atoms containing 1 to 2 aryl, oxygen, nitrogen or sulfur Heteroaryl or C ₁ to C ₄ Alkoxy,

R2 is C ₅ ~ C ₁₀ Aryl, 5 to 10 atoms Heteroaryl, C ₅ -C ₁₀ Cycloalkyl or a 5 to 10 membered heterocycle group containing 1-2 oxygen or nitrogen,

The aryl group is unsubstituted or halogen, nitro, C ₁ ~ C ₄ Linear or pulverized alkyl, trifluoromethyl, hydroxy, amino, C ₁ to C ₄ It may be substituted with any one or more substituents selected from the group consisting of alkoxy and 5 to 10 membered heterocycle containing 1-2 oxygen or nitrogen,

The heteroaryl group is a mono or bicyclic heteroaryl ring, and the heteroaryl ring is unsubstituted or halogen, C ₅ -C ₁₀ aryl, nitro, amino group, C ₁ -C ₄ straight or crushed alkyl group and C May be substituted with any one or more substituents consisting of ₁ to C ₄ alkoxy groups,

The heterocycloalkyl group may be substituted with unsubstituted, straight chain or ground C ₁ ~ C ₄ alkoxy.

Since the imidazole pyrazine derivative compound of the present invention is excellent in inhibiting the growth of influenza A virus and has fewer side effects, the composition containing the same can be usefully used as an influenza preventive and therapeutic agent.

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

The present invention provides a novel imidazole pyrazine derivative represented by the following formula (1) or a pharmaceutically acceptable salt thereof:

[Formula 1]

In Chemical Formula 1,

n is an integer from 0 to 4,

R 1 is a C ₁ to C ₄ straight or crushed alkyl group, C ₅ to C ₁₀ Cycloalkyl, C ₅ to C ₁₀ 5 to 10 atoms containing 1 to 2 aryl, oxygen, nitrogen or sulfur Heteroaryl or C ₁ to C ₄ Alkoxy,

R2 is C ₅ ~ C ₁₀ Aryl, 5 to 10 atoms Heteroaryl, C ₅ -C ₁₀ Cycloalkyl or a 5 to 10 membered heterocycle group containing 1-2 oxygen or nitrogen,

The aryl group is unsubstituted or halogen, nitro, C ₁ ~ C ₄ Linear or pulverized alkyl, trifluoromethyl, hydroxy, amino, C ₁ to C ₄ It may be substituted with any one or more substituents selected from the group consisting of alkoxy and 5 to 10 membered heterocycle containing 1-2 oxygen or nitrogen,

The heteroaryl group is a mono or bicyclic heteroaryl ring, and the heteroaryl ring is unsubstituted or halogen, C ₅ -C ₁₀ aryl, nitro, amino group, C ₁ -C ₄ straight or crushed alkyl group and C May be substituted with any one or more substituents consisting of ₁ to C ₄ alkoxy groups,

The heterocycloalkyl group may be substituted with unsubstituted, straight chain or ground C ₁ ~ C ₄ alkoxy.

In another aspect, the present invention provides a method for preparing an amidazole pyrazine derivative represented by the following formula (1).

<Scheme 1>

(In Scheme 1, n, R1 and R2 are as defined in formula 1 of claim 1).

In the preparation method of the present invention, as shown in Scheme 1,

The imidazole-pyrazine derivative of Chemical Formula 1 may be synthesized by reacting 2-amino-pyrazine of Chemical Formula 2 with the substituted-aldehyde derivative of Chemical Formula 3 and the substituted-isocyano derivative of Chemical Formula 4.

The 2-aminopyrazine compound of Formula 2 may be used by purchasing a commercially available material, and the Formula 3 and Formula 4 derivatives may be a commercially available material according to the type of substituent, or may be used in the art. Those skilled in the art can easily manufacture and use.

In more detail the preparation method of Scheme 1, a commercially available 2-aminopyrazine compound of Formula 2, a substituted-aldehyde derivative of Formula 3 and a substituted-isocyano derivative of Formula 4 are methanol / methylene Under a scandium (III) trifluoroethane sulfonate catalyst in a chloride mixed solvent, the reaction is completed within 1 to 24 hours in a temperature range of 0 to 50 ° C. depending on the type.

In the present invention, the imidazole pyrazine derivative according to Formula 1 provides a pharmaceutical composition for treating or preventing influenza virus, which comprises a pharmaceutically acceptable salt thereof as an active ingredient.

The compounds represented by the formula (1) may be administered orally or parenterally, for example, intravenously, subcutaneously, intraperitoneally or topically, during clinical administration, and may be used in the form of general pharmaceutical preparations.

Clinical use of the pharmaceutical composition of the present invention may be combined with a conventional carrier in the pharmaceutical field for oral administration of a conventional agent in the pharmaceutical field, for example, tablets, capsules, troches, solutions, suspensions, and the like. Formulations; It may be formulated into a variety of preparations, such as injectable solutions or suspensions, or injectable preparations in the form of ready-to-use injectable dry powders that can be prepared and used as injectable distilled water at the time of injection.

The effective dose of the compound of formula 1 is generally 10-500 mg / kg in adults, preferably 50-300 mg / kg, several times a day at regular time intervals, preferably 1 per day, at the discretion of the physician or pharmacist. May be administered in six divided doses.

Hereinafter, the present invention will be described in detail by way of examples.

However, the following examples are merely to illustrate the present invention is not limited to the contents of the present invention.

Manufacturing example  1: 2,6- Dichloro -4- Hydroxymethyl Preparation of Phenol

Lithium aluminum hydride (3.399 g, 85.1 mmol) was slowly added to tetrahydrofuran (70.5 mL), which was cooled to 0 ° C. using an ice bath. Ethyl 3,5-dichloro-4-hydroxy benzoate (10 g, 42.5 mmol) dissolved in tetrahydrofuran (70.5 mL) was slowly added dropwise for 1 hour. Stir for 2 hours while raising the temperature to room temperature. Lower the temperature to 0 ° C. using an ice bath, then slowly add water (3.4 mL), 2 N sulfuric acid (6.8 mL), and again water (10.2 mL). After raising the temperature to room temperature, anhydrous magnesium sulfate was added thereto. The pad was made of celite, filtered and distilled under reduced pressure to obtain the title compound (6.627 g, yield: 80.7%).

¹ H NMR (400 MHz, CDCl ₃ ) d 7.28 (s, 2H), 5.90 (brs, 1H), 4.60 (s, 2H), 1.78 (brs, 1H)

Manufacturing example  2: 3,5- Dichloro -4- Hydroxy - Benzaldehyde  Produce

2,6-Dichloro-4-hydroxymethyl-phenol (4.335 g, 22.5 mmol) was dissolved in 1,4-dioxane (45 mL). 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (5.2 g, 22.5 mmol) was added and stirred at room temperature for 12 hours. After distillation under reduced pressure, it was dissolved in dichloromethane (75 ml). The pad was made of celite, filtered and dried over anhydrous magnesium sulfate. Distillation under reduced pressure and recrystallization with ethyl acetate and hexane gave the title compound (2 g, yield: 46.6%).

¹ H NMR (400 MHz, CDCl ₃ ) d 9.82 (s, 1H), 7.83 (s, 2H), 6.42 (s, 1H)

Example  1: 4- (3- ( Benzylamino ) Imidazo [1,2- a ] Pyrazin-2-yl) -2,6- Dichlorophenol  Produce

Aminopyrazine (30 mg, 0.32 mmol) was dissolved in dichloromethane (0.48 mL) and methanol (0.16 mL), and then 3,5-dichloro-4-hydroxy-benzaldehyde synthesized in Preparation Examples 1 and 2 ( 60 mg, 0.32 mmol), benzyl isocyanide (40 mg, 0.32 mmol) and scandium triflate (7.8 mg, 0.016 mmol) were added. Stir at room temperature for 16 hours. The resulting solid was filtered to give the title compound (40 mg, yield: 33%).

¹ H NMR (400 MHz, CDCl ₃ ) d 8.9 (d, 1H, J = 1.2 Hz), 7.94 (s, 2H), 7.8 (d, 1H, J = 4.4 Hz), 7.78 (dd, 1H, J = 1.2, 4.6 Hz), 7.3 (m, 3H), 7.25 (d, 2H, J = 4.0 Hz), 4.23 (d, 2H, J = 6.4 Hz), 3.49 (s, 1H), 3.43 (t, 1H, J = 6.0 Hz)

Example  2: 5- (3- ( Cyclopentylamino ) Imidazo [1,2-a] pyrazin-2-yl) -2- Methoxyphenolic  Produce

2-amino-pyrazine (500 mg, 5.3 mmol) was dissolved in dichloromethane (1.2 mL) and methanol (0.5 mL), followed by 3-hydroxy-4-methoxybenzaldehyde (880 mg, 5.83 mmol) and cyclo Petyl isocyanide (566 mg, 5.83 mmol) and scandium triflate (15.6 mg, 0.032 mmol) were added. Stir at room temperature for 20 hours and filter the resulting solid to give the title compound (1.3 mg, yield: 73%).

¹ H NMR (400 MHz, DMSO) d 8.962 (dd, 1H, J = 3.628, J = 1.844), 8.613 (dd, 1H, J = 6.681, J = 3.628), 7.953 (dd, 1H, J = 6.681, J = 1.844), 7.699 (dd, 1H, J = 8.830, J = 2.748), 6.975 (dd, 1H, J = 2.748, J = 2.374), 6.859 (dd, 1H, J = 8.830, J = 2.374), 4.012 (m, 1H), 3.699 (s, 3H), 1.923-1.838 (m, 4H), 1.595-1.540 (m, 4H)

Through the same synthesis method as in Example 1, to prepare a compound of Examples 1 to 35. Table 1 shows the ¹ H-NMR results for the compounds prepared in Examples 1 to 35.

Example designation constitutional formula NMR data



One
4- (3- (benzylamino) imidazo [1,2- a ] pyrazin-2-yl) -2,6-dichloro-phenol

NMR (400 MHz, CDCl ₃ ) d 8.9 (d, 1H, J = 1.2 Hz), 7.94 (s, 2H), 7.8 (d, 1H, J = 4.4 Hz), 7.78 (dd, 1H, J = 1.2, 4.6 Hz), 7.3 (m, 3H), 7.25 (d, 2H, J = 4.0 Hz), 4.23 (d, 2H, J = 6.4 Hz), 3.49 (s, 1H), 3.43 (t, 1H, J = 6.0 Hz)





2


5- (3- (cyclopentylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol

NMR (400 MHz, DMSO) d 8.962 (dd, 1H, J = 3.628, J = 1.844), 8.613 (dd, 1H, J = 6.681, J = 3.628), 7.953 (dd, 1H, J = 6.681, J = 1.844), 7.699 (dd, 1H, J = 8.830, J = 2.748), 6.975 (dd, 1H, J = 2.748, J = 2.374), 6.859 (dd, 1H, J = 8.830, J = 2.374), 4.012 ( m, 1H), 3.699 (s, 3H), 1.923-1.838 (m, 4H), 1.595-1.540 (m, 4H)



3


2- (3- (cyclopentylamino) imidazo [1,2-a] pyrazin-2-yl) phenol

NMR (400 MHz, DMSO) d 9.031 (dd, 1H, J = 3.853, J = 1.983), 8.656 (dd, 1H, J = 7.865, J = 3.853), 7.955 (m, 1H), 7.706 (dd, 1H , J = 7.865, J = 1.983), 7.188 (m, 1H), 7.171 (m, 1H), 7.126 (m, 1H), 4.124 (m, 1H), 1.923-1.833 (m, 4H), 1.594-1.539 (m, 4H)





4


2-ethoxy-4- (3-(((tetrahydrofuran-2-yl) methyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenol

NMR (400 MHz, DMSO) d
8.968 (dd, 1H, J = 3.529, J = 1.970), 8.617 (dd, 1H, J = 6.665, J = 3.529), 7.956 (dd, 1H, J = 6.665, J = 1.970), 7.154 (dd, 1H , J = 8.328, J = 2.478), 6.912 (dd, 1H, J = 8.328, J = 2.141), 6.907 (dd, 1H, J = 2.478, J = 2.141), 3.938 (m, 1H), 3.922 (q , 2H, J = 6.957), 3.823-3.654 (m, 4H), 2.017-1.898 (m, 4H), 1.252 (t, 3H, J = 6.957)




5


5- (3-((2-hydroxyethyl) amino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol

NMR (400 MHz, DMSO) d
8.961 (dd, 1H, J = 3.651, J = 1.968), 8.612 (dd, 1H, J = 6.914, J = 3.651), 7.970 (dd, 1H, J = 6.914, J = 1.968), 7.690 (dd, 1H , J = 8.829, J = 2.714), 6.975 (dd, 1H, J = 2.714, J = 2.062), 6.923 (dd, 1H, J = 8.829, J = 2.062), 3.700 (s, 3H), 3.662-3.564 (m, 4H), 3.210 (s, 3H)




6


N- (furan-2-ylmethyl) -2- (2-methoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.011 (dd, 1H, J = 3.961, J = 1.985), 8.646 (dd, 1H, J = 7.637, J = 3.961), 8.008 (m, 1H), 7.685 (dd, 1H, J = 7.637, J = 1.985 ), 7.358 (dd, 1H, J = 1.753, J = 1.103), 7.218 (m, 1H), 7.169-7.159 (m, 2H), 6.239 (dd, 1H, J = 3.392, J = 1.753), 6.166 ( dd, 1H, J = 3.392, J = 1.103), 4.963 (s, 2H), 3.729 (s, 3H)




7


N- (2-methoxyethyl) -2- (4- (pyrrolidin-1-yl) phenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.955 (dd, 1H, J = 4.146, J = 1.872), 8.599 (dd, 1H, J = 7.537, J = 4.146), 8.111 (m, 1H), 7.924 (dd, 1H, J = 7.537, J = 1.872 ), 7.856 (m, 1H), 7.034-7.033 (m, 2H), 3.448-3.386 (m, 4H), 3.630-3.565 (m, 4H), 3.210 (s, 3H), 1.947-1.919 (m, 4H) )





8



2- (4- (diethylamino) phenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.863 (dd, 1H, J = 3.906, J = 1.756), 8.542 (dd, 1H, J = 7.238, J = 3.906), 8.066 (dd, 1H, J = 8.302, J = 4.299), 7.795 (dd, 1H , J = 7.238, J = 1.756), 6.614-6.590 (m, 2H), 3.935 (m, 1H), 3.823 (m, 1H), 3.739 (m, 2H), 3.654 (m, 1H), 3.604 (s , 3H), 3.394-3.391 (m, 4H), 2.016-1.898 (m, 4H), 1.101-1.100 (m, 6H)





9



(5- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenyl) methanol

NMR (400 MHz, DMSO) d
8.971 (dd, 1H, J = 4.298, J = 1.978), 8.617 (dd, 1H, J = 7.534, J = 4.298), 7.954 (dd, 1H, J = 7.534, J = 1.978), 7.826 (dd, 1H , J = 1.937, J = 1.083), 7.758 (dd, 1H, J = 8.651, J = 1.937), 7.025 (dd, 1H, J = 8.651, J = 1.083), 4.348 (s, 2H), 3.896 (m , 1H), 3.692 (s, 3H), 1.972 (m, 4H), 1.685 (m, 4H), 1.502-1.470 (m, 4H), 1.378-1.357 (m, 2H)




10
N-benzyl-2- (1,5-dimethyl-1H-pyrazol-4-yl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.998 (dd, 1H, J = 2.941, J = 1.958), 8.562 (dd, 1H, J = 7.614, J = 2.941), 7.614 (dd, 1H, J = 7.614, J = 1.958), 7.514 (s, 1H ), 7.392 (m, 2H), 7.333 (m, 2H), 7.231 (m, 1H), 4.738 (s, 2H), 3.680 (s, 3H), 2.388 (s, 3H)




11

N-cyclopentyl-2- (2- (dimethylamino) pyrimidin-5-yl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.008 (dd, 1H, J = 4.431, J = 1.980), 8.687 (dd, 1H, J = 7.649, J = 4.431), 8.526 (d, 1H, J = 1.950), 8.262 (d, 1H, J = 1.950 ), 8.037 (dd, 1H, J = 7.649, J = 1.980), 4.149 (m, 1H), 2.832 (s, 6H), 1.965 (m, 2H), 1.867 (m, 2H), 1.593-1.540 (m , 4H)





12



N- (benzo [d] [1,3] dioxol-5-ylmethyl) -2- (thiophen-2-yl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.110 (dd, 1H, J = 2.581, J = 1.952), 8.602 (dd, 1H, J = 7.709, J = 2.581), 7.664 (dd, 1H, J = 7.709, J = 1.952), 7.255 (dd, 1H , J = 5.079, J = 1.174), 7.104 (dd, 1H, J = 7.289, J = 1.174), 7.017 (dd, 1H, J = 7.289, J = 5.079), 6.885-6.846 (m, 2H), 6.783 (dd, 1H, J = 2.783, J = 0.949), 5.929-5.927 (d, 2H, J = 10.688), 4.501 (s, 2H)




13


2- (2- (dimethylamino) pyrimidin-5-yl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.008 (dd, 1H, J = 4.405, J = 1.987), 8.699 (dd, 1H, J = 7.615, J = 4.405), 8.481 (d, 1H, J = 1.951), 8.289 (d, 1H, J = 1.951 ), 8.175 (dd, 1H, J = 7.615, J = 1.987), 3.935-3.873 (m, 2H), 3.707 (d, 2H, J = 5.279), 3.639 (m, 1H), 2.831 (s, 6H) , 2.113-2.021 (m, 2H), 1.973-1.901 (m, 2H)





14



4- (3-(((tetrahydrofuran-2-yl) methyl) amino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol

NMR (400 MHz, DMSO) d
8.984 (dd, 1H, J = 3.511, J = 1.879), 8.626 (dd, 1H, J = 7.563, J = 3.511), 7.959 (dd, 1H, J = 7.563, J = 1.879), 7.155 (dd, 1H , J = 8.295, J = 1.836), 6.920 (dd, 1H, J = 8.295, J = 2.346), 6.898 (dd, 1H, J = 2.346, J = 1.836), 3.937-3.823 (m, 2H), 3.682 -3.654 (m, 4H), 2.017-1.898 (m, 2H)





15


4- (3-((4-fluorobenzylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol

NMR (400 MHz, DMSO) d
8.984 (dd, 1H, J = 3.514, J = 1.970), 8.628 (dd, 1H, J = 6.905, J = 3.514), 7.987 (dd, 1H, J = 6.905, J = 1.970), 7.270 (m, 2H ), 7.216 (m, 1H), 7.157 (dd, 1H, J = 8.295, J = 1.836), 7.056 (m, 1H), 6.920 (dd, 1H, J = 8.295, J = 2.341), 6.899 (dd, 1H, J = 2.341, J = 1.836), 4.854 (s, 2H)




16


N- (tert-butyl) -2- (furan-2-yl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.110 (dd, 1H, J = 2.822, J = 1.951), 8.606 (dd, 1H, J = 7.688, J = 2.822), 7.662 (dd, 1H, J = 7.688, J = 1.951), 7.286 (dd, 1H , J = 1.753, J = 0.761), 6.522 (dd, 1H, J = 3.389, J = 0.761), 6.321 (dd, 1H, J = 3.389, J = 1.753), 1.277 (s, 9H)





17



2- (3,4-dimethoxyphenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.95 (dd, 1H, J = 3.6 Hz, J = 1.8 Hz), 8.60 (dd, 1H, J = 6.7 Hz, J = 3.6 Hz), 7.94 (dd, 1H, J = 6.7 Hz, J = 1.8 Hz) , 7.13 (dd, 1H, J = 8.8 Hz, J = 2.5 Hz), 6.94-6.89 (m, 2H), 3.94 (m, 1H), 3.82 (m, 1H), 3.71 (s, 3H), 3.70 ( d, 2H, J = 5.8 Hz), 3.65 (m, 1H), 3.65 (m, 1H), 3.64 (s, 3H), 2.02 (m, 1H), 2.01 (m, 1H), 1.93 (m, 1H ), 1.90 (m, 1 H)






18



4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol

NMR (400 MHz, DMSO) d
8.98 (dd, 1H, J = 3.5 Hz, J = 1.9 Hz), 8.63 (dd, 1H, J = 7.6 Hz, J = 3.5 Hz), 7.96 (dd, 1H, J = 7.6 Hz, J = 1.9 Hz) , 7.16 (dd, 1H, J = 8.3 Hz, J = 1.8 Hz), 6.92 (dd, 1H, J = 8.3 Hz, J = 2.4 Hz), 6.90 (dd, 1H, J = 2.4 Hz, J = 1.8 Hz ), 3.88 (m, 1H), 1.97 (m, 2H), 1.69 (m, 2H), 1.50 (m, 2H), 1.47 (m, 2H), 1.38 (m, 1H), 1.36 (m, 1H)





19



4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,3-diol

NMR (400 MHz, DMSO) d
8.98 (dd, 1H, J = 3.9 Hz, J = 1.9 Hz), 8.62 (dd, 1H, J = 7.6 Hz, J = 3.9 Hz), 8.13 (dd, 1H, J = 8.4 Hz, J = 0.5 Hz) , 7.95 (dd, 1H, J = 7.6 Hz, J = 1.9 Hz), 6.28 (dd, 1H, J = 8.4 Hz, J = 1.6 Hz), 6.67 (dd, 1H, J = 1.6 Hz, J = 0.5 Hz ), 3.88 (m, 1H), 1.97 (m, 2H), 1.69 (m, 2H), 1.50 (m, 2H), 1.47 (m, 2H), 1.38 (m, 1H), 1.36 (m, 1H)






20



2-ethoxy-4- (3-((thiophen-2-ylmethyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenol

NMR (400 MHz, DMSO) d
8.97 (dd, 1H, J = 3.5 Hz, J = 2.0 Hz), 8.62 (dd, 1H, J = 6.9 Hz, J = 3.5 Hz), 8.12 (dd, 1H, J = 6.9 Hz, J = 2.0 Hz) , 7.55 (dd, 1H, J = 8.1 Hz, J = 5.3 Hz), 7.52 (dd, 1H, J = 8.8 Hz, J = 2.5 Hz), 7.41 (dd, 1H, J = 5.3 Hz, J = 1.3 Hz ), 7.03 (dd, 1H, J = 8.1 Hz, J = 1.3 Hz), 6.94 (dd, 1H, J = 8.8 Hz, J = 2.8 Hz), 6.91 (dd, 1H, J = 2.8 Hz, J = 2.5 Hz), 4.91 (s, 2H), 4.21 (q, 2H, J = 7.0 Hz), 1.25 (t, 3H, J = 7.0 Hz)





21


2- (4- (ethyloxy) -3-methoxyphenyl) -N- (thiophen-2-ylmethyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.95 (dd, 1H, J = 3.6 Hz, J = 2.0 Hz), 8.61 (dd, 1H, J = 6.9 Hz, J = 3.6 Hz), 8.12 (dd, 1H, J = 6.9 Hz, J = 2.0 Hz) , 7.43 (dd, 1H, J = 5.3 Hz, J = 1.4 Hz), 7.30 (dd, 1H, J = 8.1 Hz, J = 5.3 Hz), 7.15 (dd, 1H, J = 8.8 Hz, J = 2.5 Hz ), 7.04 (dd, 1H, J = 8.1 Hz, J = 1.4 Hz), 6.90 (m, 2H), 4.91 (s, 2H), 4.48 (s, 2H), 3.63 (s, 3H), 2.79 (s , 1H)






22



4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol

NMR (400 MHz, DMSO) d
8.96 (dd, 1H, J = 3.6 Hz, J = 1.8 Hz), 8.61 (dd, 1H, J = 6.7 Hz, J = 3.6 Hz), 7.95 (dd, 1H, J = 6.8 Hz, J = 1.8 Hz) , 7.13 (dd, 1H, J = 8.8 Hz, J = 2.4 Hz), 6.95 (dd, 1H, J = 8.8 Hz, J = 2.3 Hz), 6.89 (dd, 1H, J = 2.4 Hz, J = 2.3 Hz ), 3.87 (m, 1H), 3.70 (s, 3H), 1.97 (m, 2H), 1.69 (m, 2H), 1.50 (m, 2H), 1.47 (m, 2H), 1.38 (m, 1H) , 1.36 (m, 1H)



23

2- (4-bromothiophen-2-yl) -N- (2-methoxyethyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.17 (dd, 1H, J = 3.0 Hz, J = 1.9 Hz), 8.63 (dd, 1H, J = 7.7 Hz, J = 3.0 Hz), 7.72 (dd, 1H, J = 7.7 Hz, J = 1.9 Hz) , 7.39 (d, 1H, J = 2.0 Hz), 6.93 (d, 1H, J = 2.0 Hz), 3.63 (t, 2H, J = 6.9 Hz), 3.50 (t, 2H, J = 6.9 Hz), 3.21 (s, 3H)




24

4- (3-((4-methoxybenzyl) amino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,3-diol

NMR (400 MHz, DMSO) d
8.97 (dd, 1H, J = 3.8 Hz, J = 2.0 Hz), 8.62 (dd, 1H, J = 6.9 Hz, J = 3.8 Hz), 8.13 (m, 2H), 7.25-7.24 (m, 2H), 7.00 (m, 2H), 6.67 (dd, 1H, J = 1.7 Hz, J = 0.5 Hz), 6.61 (dd, 1H, J = 8.4 Hz, 1.66 Hz), 4.82 (s, 2H), 3.74 (s, 3H)




25

N-((tetrahydrofuran-2-yl) methyl) -2- (2,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.86 (dd, 1H, J = 3.6 Hz, J = 1.7 Hz), 8.57 (dd, 1H, J = 7.6 Hz, J = 3.6 Hz), 7.80 (dd, 1H, J = 7.6 Hz, J = 1.7 Hz) , 6.97 (d, 1H, J = 2.7 Hz), 6.41 (d, 1H, J = 2.7 Hz), 3.94 (m, 1H), 3.82 (m, 1H), 3.73 (d, 2H, J = 4.7 Hz) , 3.69 (s, 3H), 3.65 (m, 4H), 3.64 (s, 3H), 2.01-2.00 (m, 2H), 1.93 (m, 1H), 1.90 (m, 1H)



26
2- (6-chlorobenzo [d] [1,3] dioxol-5-yl) -N- (4-fluorobenzyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.94 (dd, 1H, J = 3.9 Hz, J = 1.8 Hz), 8.60 (dd, 1H, J = 7.5 Hz, J = 3.9 Hz), 7.93 (dd, 1H, J = 7.5 Hz, J = 1.8 Hz) , 7.27 (m, 2H), 7.12 (m, 1H), 7.11 (d, 1H, J = 1.4 Hz), 6.92 (m, 1H), 6.88 (d, 1H, J = 1.4 Hz), 6.02-6.01 ( m, 2H)






27



2- (4- (pyrrolidin-1-yl) phenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.96 (dd, 1H, J = 4.1 Hz, J = 1.9 Hz), 8.60 (dd, 1H, J = 7.6 Hz, J = 4.1 Hz), 7.93 (m, 1H), 7.91 (dd, 1H, J = 7.6 Hz, 1.9 Hz), 7.83 (m, 1H), 7.04-7.03 (m, 2H), 3.93 (m, 1H), 3.82 (m, 1H), 3.68 (d, 2H, J = 5.8 Hz), 3.65 ( m, 1H), 3.49 (m, 1H), 3.45 (m, 1H), 3.39 (m, 2H), 2.02-2.01 (m, 2H), 1.95 (m, 2H), 1.93-1.92 (m, 3H) , 1.90 (m, 1H)





28


N-cyclopentyl-2- (3,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.96 (dd, 1H, J = 3.7 Hz, J = 1.9 Hz), 8.61 (dd, 1H, J = 7.0 Hz, J = 3.7 Hz), 7.91 (dd, 1H, J = 7.0 Hz, J = 1.9 Hz) , 6.78 (d, 1H, J = 2.6 Hz), 6.73 (d, 1H, J = 2.6 Hz), 3.77 (m, 1H), 3.65 (s, 6H), 3.64 (s, 3H), 2.04 (m, 1H), 1.94 (m, 1H), 1.90 (m, 1H), 1.85 (m, 1H), 1.76 (m, 1H), 1.64-1.62 (m, 2H), 1.56 (m, 1H)






29



(2-methoxy-5- (3-((thiophen-2-ylmethyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenyl) methanol

NMR (400 MHz, DMSO) d
8.97 (dd, 1H, J = 4.2 Hz, J = 2.0 Hz), 8.62 (dd, 1H, J = 6.9 Hz, J = 4.2 Hz), 8.03 (dd, 1H, J = 6.9 Hz, J = 2.0 Hz) , 7.74 (dd, 1H, J = 8.8 Hz, J = 1.9 Hz), 7.67 (dd, 1H, J = 1.9 Hz, J = 0.4 Hz), 7.55 (dd, 1H, J = 8.1 Hz, J = 5.3 Hz ), 7.41 (dd, 1H, J = 5.3 Hz, J = 1.4 Hz), 7.03 (dd, 1H, J = 8.1 Hz, J = 1.3 Hz), 6.93 (dd, 1H, J = 8.8 Hz, J = 0.4 Hz), 4.91 (s, 2H), 4.35 (s, 2H), 3.69 (s, 3H)






30



2- (1,5-dimethyl-1H-pyrazol-4-yl) -N- (thiophen-2-ylmethyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.99 (dd, 1H, J = 2.9 Hz, J = 2.0 Hz), 8.56 (dd, 1H, J = 7.6 Hz, J = 2.9 Hz), 7.62 (dd, 1H, J = 7.6 Hz, J = 2.0 Hz) , 7.74 (dd, 1H, J = 8.8 Hz, J = 1.9 Hz), 7.67 (dd, 1H, J = 1.9 Hz, J = 0.4 Hz), 7.52 (s, 1H), 7.37 (dd, 1H, J = 5.0 Hz, J = 1.3 Hz), 7.19 (dd, 1H, J = 8.2 Hz, J = 5.0 Hz), 7.14 (dd, 1H, J = 8.2 Hz, J = 1.3 Hz), 4.86 (s, 2H), 3.68 (s, 3H), 2.34 (s, 3H)



31

N- (tert-butyl) -2- (2,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.86 (dd, 1H, J = 3.6 Hz, J = 1.7 Hz), 8.57 (dd, 1H, J = 7.6 Hz, J = 3.6 Hz), 7.80 (dd, 1H, J = 7.6 Hz, J = 1.7 Hz) , 6.97 (d, 1H, J = 2.7 Hz), 6.41 (d, 1H, J = 2.7 Hz), 3.69 (s, 3H), 3.65 (s, 6H), 1.34 (s, 9H)



32

5- (3- (benzylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol

NMR (400 MHz, DMSO) d
8.97 (dd, 1H, J = 3.6 Hz, J = 2.0 Hz), 8.62 (dd, 1H, J = 6.7 Hz, J = 3.6 Hz), 7.96 (dd, 1H, J = 6.7 Hz, J = 2.0 Hz) , 7.24-7.23 (m, 3H), 7.21 (m, 2H), 7.15 (dd, 1H, J = 8.3 Hz, J = 2.5 Hz), 6.91-6.90 (m, 2H), 4.86 (s, 2H), 3.68 (s, 3 H)




33


N- (benzo [d] [1,3] dioxol-5-ylmethyl) -2- (3-methoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
9.03 (dd, 1H, J = 3.7 Hz, J = 2.0 Hz), 8.66 (dd, 1H, J = 6.9 Hz, J = 3.7 Hz), 7.99 (dd, 1H, J = 6.9 Hz, J = 2.0 Hz) , 7.47 (m, 1H), 7.09 (m, 1H), 6.96 (m, 1H) 6.88 (dd, 1H, J = 8.5 Hz, J = 2.8 Hz), 6.85 (dd, 1H, J = 8.5 Hz, J = 1.2 Hz), 6.78-6.76 (m, 2H), 5.93-5.92 (m, 2H), 4.63 (s, 2H), 3.64 (s, 3H)





34


(2-methoxy-5- (3-((4-methylbenzyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenyl) methanol

NMR (400 MHz, DMSO) d
8.97 (dd, 1H, J = 4.3 Hz, J = 2.0 Hz), 8.62 (dd, 1H, J = 7.0 Hz, J = 4.3 Hz), 8.00 (dd, 1H, J = 7.0 Hz, J = 2.0 Hz) , 7.71 (dd, 1H, J = 8.8 Hz, J = 1.9 Hz), 7.66 (dd, 1H, J = 1.9 Hz, J = 0.4 Hz), 7.06 (m, 1H), 7.04 (m, 1H), 6.96 (dd, 1H, J = 8.8 Hz, J = 0.4 Hz), 6.93 (m, 2H), 4.84 (s, 2H), 4.38 (s, 2H), 3.69 (s, 3H), 2.26 (s, 3H)




35


N- (tert-butyl) -2- (2,4-dimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine

NMR (400 MHz, DMSO) d
8.93 (dd, 1H, J = 3.9 Hz, J = 1.8 Hz), 8.59 (dd, 1H, J = 7.5 Hz, J = 4.0 Hz), 7.96 (dd, 1H, J = 8.4 Hz, J = 5.5 Hz) , 7.84 (dd, 1H, J = 7.5 Hz, J = 1.8 Hz), 6.64 (dd, 1H, J = 5.5 Hz, J = 1.6 Hz), 6.50 (dd, 1H, J = 8.4 Hz, J = 1.6 Hz ), 3.70 (s, 3H), 3.59 (s, 3H), 1.34 (s, 9H)

Experimental Example  : Plaque formation inhibition experiment

Plaque formation inhibition experiment was conducted to determine the effect of the compounds synthesized in the above example on the activity of the flu virus. One day before the experiment, 1.5 × 10 ⁵ MDCK (Mardine Darbine Canine Kidney) cell line (ATCC, USA) was added to MEM (Minimum Essencial Medium: GIBCO Invitrogen Coporation, USA) medium containing FBS (Fetal Bovine Serum: GIBCO Invitrogen Coporation, USA). After inoculation at a concentration of cells / ml, the cells were incubated in a 6-well plate at 37 ° C. and 5% CO 2 concentration. Two subtypes of the flu virus, A / Chile / 1/83 (H1N1) and A / Sydney / 5/97 (H3N2), were grown in an MDCK cell line that grew to the bottom of the petri dish after 24 hours. , UK) was infected at a concentration of 500 PFU (Plaque Forming Unit) / ml.

After one hour, the treated virus solution was removed from the cells, and the cell lines were washed with 1 ml / well of PBS (Photasium Phosphate Buffered Saline) buffer. After diluting the Example compound of Table 1 to a final concentration from 100 μM to 15 μM, it was overlayed with DMEM (Dulbecco's Modified Eagle's) containing trypsinase at a concentration of 1% agarose and 10 μg / ml. Medium: GIBCO Invitrogen Coporation, USA) medium added to the plate for plaque formation] and green tea and catechin (EGC and (+)-C), which is the backbone of the catechin derivative instead of the catechin derivative compound as a control. EGCG, ECG and nothing added overlay medium was used. The overlay medium was plated by 3 ml / well of cells infected with the flu virus, and after 15 minutes, the overlay medium was solidified and incubated for 72 hours in an incubator maintaining 5% CO 2 concentration at 37 ° C.

After 72 hours of incubation, plaque formation can be observed with the naked eye. At this time, fixate with formalin for 20 minutes, remove agarose from flowing water, and dye 1% (w / v) crystal violet. Stain with a solution (crystal violet staining solution). The number of plaques was visually counted and compared with the control group to confirm plaque inhibition. As a result, influenza virus formed plaques for 72 hours, and plaque formation was inhibited in the experimental group to which the compounds of the present invention (Table 2) were added. When the number of plaques after the number of plaques is the ratio of the number of plaques in the control group and the number of plaques in the experimental group, the activity of inhibiting plaque formation of the flu virus by the example compound of the present invention (Table 2) is active at a concentration of 1 μM or less. In the case of +++, 1 to 10 μM, ++, and in the case of 10 to 100 μM, + is indicated.

Influenza virus inhibition of the compound derivative of Formula 1 prepared through Examples 1 to 35 is shown in Table 2 below.

Example Plaque assay
activation 100uM 10uM 1uM
One

+++
2

++
3

-
4

-
5

-
6

-
7

++
8

-
9

++
10

++
11

+++

12

-

13

-
14

++
15

++
16

++
17

-
18

-
19

++
20

-


21

-
22

++
23

-
24

-
25

-
26

-
27

-
28

-
29

-
30

-
31

-
32

+
33
-
34

-
35

+   0.1 ~ 1 uM       +++
  1 to 10 uM        ++
  10-100 uM      +
  > 100 uM       -

As shown in Table 2, the novel imidazole pyrazine derivative represented by Chemical Formula 1 according to the present invention has an excellent effect of inhibiting the proliferation against the flu virus, and thus may be usefully used as a prophylactic and therapeutic agent for the flu virus. In addition, it can be usefully used as a combination therapy with the compounds of the present invention in order to solve the problems of toxicity and resistance virus of the conventionally used flu therapy.

Claims (8)

Novel imidazolpyrazine derivatives represented by Formula 1 or a pharmaceutically acceptable salt thereof:
[Formula 1]
         

In Chemical Formula 1,
n is an integer from 0 to 4,
R1 is C_One~ C₄Linear or pulverized alkyl groups of C,₅~ C₁₀ Cycloalkyl, C₅~ C₁₀ 5 to 10 atoms containing 1 to 2 aryl, oxygen, nitrogen or sulfur Heteroaryl or C_One~ C₄ Alkoxy,
R1 is C_One~ C₄Linear or pulverized alkyl groups of C,₅~ C₁₀Cycloalkyl, C₅~ C₁₀5 to 10 atoms containing 1 to 2 aryl, oxygen, nitrogen or sulfur Heteroaryl or C_One~ C₄ Alkoxy,
R2 is C₅~ C₁₀of Aryl, 5 to 10 atoms Heteroaryl, C₅~ C₁₀ Cycloalkyl or a 5 to 10 membered heterocycle group containing 1-2 oxygen or nitrogen,
The aryl group is unsubstituted or halogen, nitro, C_One~ C₄ Linear or pulverized alkyl, trifluoromethyl, hydroxy, amino, C_One~ C₄ It may be substituted with any one or more substituents selected from the group consisting of alkoxy and 5 to 10 membered heterocycle containing 1-2 oxygen or nitrogen,
The hetero aryl group is a mono or bicyclic heteroaryl ring, the hetero aryl ring is unsubstituted or halogen, C₅~ C₁₀Aryl, nitro, amino, C_One~ C₄Linear or pulverized alkyl groups of C and_One~ C₄May be substituted with any one or more substituents consisting of an alkoxy group of
The heterocycloalkyl group is an unsubstituted, straight chain or crushed C_One~ C₄ It may be substituted with alkoxy.
The method of claim 1,
n is an integer from 0 to 4,
R 1 is a C ₁ to C ₄ straight or crushed alkyl group, C ₅ to C ₁₀ Cycloalkyl, C ₅ to C ₁₀ 5 to 10 atoms containing 1 or 2 aryl, oxygen, nitrogen or terms Heteroaryl or C ₁ to C ₄ Alkoxy,
R2 is C ₅ ~ C ₇ Aryl, 5 to 7 atoms Heteroaryl, C ₅ -C ₇ Cycloalkyl, or 5 to 7 membered heterocycloalkyl containing 1 to 2 oxygen or nitrogen,
The aryl group is unsubstituted or halogen, nitro, C ₁ ~ C ₄ Linear or pulverized alkyl, trifluoromethyl, hydroxy, amino, C ₁ to C ₄ It may be substituted with any one or more substituents selected from the group consisting of alkoxy and 5 to 10 membered heterocycle containing 1-2 oxygen or nitrogen,
The heteroaryl group is a mono or bicyclic heteroaryl ring, and the heteroaryl ring is unsubstituted or halogen, C ₅ -C ₁₀ aryl, nitro, amino group, C ₁ -C ₄ straight or crushed alkyl group and C May be substituted with any one or more substituents consisting of ₁ to C ₄ alkoxy groups,
The heterocycloalkyl group is a novel imidazole pyrazine derivative or a pharmaceutically acceptable salt thereof, characterized in that it may be substituted with unsubstituted, straight chain or pulverized C ₁ ~ C ₄ alkoxy.
The method of claim 1, wherein the aminopyrazine derivative
(1) 4- (3-benzylamino-imidazo [1,2- a ] pyrazin-2-yl) -2,6-dichloro-phenol;
(2) 5- (3-cyclopentylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol;
(3) 3- (3- (cyclopentylamino) imidazo [1,2-a] pyrazin-2-yl) phenol;
(4) 2-ethoxy-4- (3-(((tetrahydrofuran-2-yl) methyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenol;
(5) 5- (3-((2-hydroxyethyl) amino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol;
(6) N- (furan-2-ylmethyl) -2- (2-methoxyphenyl) imidazo [1,2-a] pyrazin-3-amine;
(7) N- (methoxymethyl) -2- (4- (pyrrolidin-1-yl) phenyl) imidazo [1,2-a] pyrazin-3-amine;
(8) 2- (4- (diethylamino) phenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine;
(9) (5- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenyl) methanol;
(10) N-benzyl-2- (1,5-dimethyl-1H-pyrazol-4-yl) imidazo [1,2-a] pyrazin-3-amine;
(11) N-cyclopentyl-2- (2- (dimethylamino) pyrimidin-5-yl) imidazo [1,2-a] pyrazin-3-amine;
(12) N- (benzo [d] [1,3] dioxol-5-ylmethyl) -2- (thiophen-2-yl) imidazo [1,2-a] pyrazin-3-amine;
(13) 2- (2- (dimethylamino) pyrimidin-5-yl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine;
(14) 4- (3-(((tetrahydrofuran-2-yl) methyl) amino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol;
(15) 4- (3- (benzylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol;
(16) N- (tert-butyl) -2- (furan-2-yl) imidazo [1,2-a] pyrazin-3-amine;
(17) 2- (3,4-dimethoxyphenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine;
(18) 4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,2-diol;
(19) 4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,3-diol;
(20) 2-ethoxy-4- (3-((thiophen-2-ylmethyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenol;
(21) 2- (4- (ethyloxy) -3-methoxyphenyl) -N- (thiophen-2-ylmethyl) imidazo [1,2-a] pyrazin-3-amine;
(22) 4- (3- (cyclohexylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol;
(23) 2- (4-bromothiophen-2-yl) -N- (2-methoxyethyl) imidazo [1,2-a] pyrazin-3-amine;
(24) 4- (3-((4-methoxybenzyl) amino) imidazo [1,2-a] pyrazin-2-yl) benzene-1,3-diol;
(25) N-((tetrahydrofuran-2-yl) methyl) -2- (2,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine;
(26) 2- (6-chlorobenzo [d] [1,3] dioxol-5-yl) -N- (4-fluorobenzyl) imidazo [1,2-a] pyrazin-3-amine;
(27) 2- (4- (pyrrolidin-1-yl) phenyl) -N-((tetrahydrofuran-2-yl) methyl) imidazo [1,2-a] pyrazin-3-amine;
(28) N-cyclopentyl-2- (3,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine;
(29) (2-methoxy-5- (3-((thiophen-2-ylmethyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenyl) methanol;
(30) 2- (1,5-dimethyl-1H-pyrazol-4-yl) -N- (thiophen-2-ylmethyl) imidazo [1,2-a] pyrazin-3-amine;
(31) N- (tert-butyl) -2- (2,4,5-trimethoxyphenyl) imidazo [1,2-a] pyrazin-3-amine;
(32) 5- (3- (benzylamino) imidazo [1,2-a] pyrazin-2-yl) -2-methoxyphenol;
(33) N- (benzo [d] [1,3] dioxol-5-ylmethyl) -2- (3-methoxyphenyl) imidazo [1,2-a] pyrazin-3-amine;
(34) (2-methoxy-5- (3-((4-methylbenzyl) amino) imidazo [1,2-a] pyrazin-2-yl) phenyl) methanol; And
(35) A novel aminopyrazine, characterized in that it is selected from the group consisting of N- (tert-butyl) -2- (2,4-dimethoxyphenyl) imidazo [1,2-a] pyrazine-3-amine. Derivatives or pharmaceutically acceptable salts thereof.
As shown in Scheme 1 below,
A method of preparing an aminopyrazine derivative comprising coupling a compound of Formula 2, a compound of Formula 3, and a compound of Formula 4 under a solvent to produce a compound of Formula 1:
<Scheme 1>

(In Scheme 1, n, R1 and R2 are as defined in formula 1 of claim 1).
5. The method of claim 4, wherein the solvent is a mixed solvent of methanol and methylene chloride 1: 3 (v / v).
A pharmaceutical composition for antiviral therapy comprising the aminopyrazine derivative of claim 1 or a pharmaceutically acceptable salt thereof as an active ingredient.
The pharmaceutical composition of claim 6, wherein the virus is a flu virus.
The pharmaceutical composition of claim 6, wherein the aminopyrazine derivative of Formula 1 or a pharmaceutically acceptable salt thereof inhibits the proliferation of the influenza virus.