JP2003012667A - Antimicrobial agent having quinolin carboxamide skelton - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compound having excellent antimicrobial activities against gram-positive bacteria and resistant gram-positive bacteria, and further having a quinolin carboxamide skeleton. SOLUTION: This compound having the quinolin carboxamide skeleton is represented by the formula (wherein, R1 is a pyridyl group, a pyrazyl group, a pyrazole group, a quinolyl group, or a isoquinolyl group; R2 , R3 , R4 , and R5 are each independently a hydrogen atom, a halogen atom, a nitro group or a hydroxy group; R6 is a lower alkyl group, a lower alkenyl group or an aralkyl group; R5 and R6 can form a heterocycle by bonding to each other in combination with a carbon atom and a nitrogen atom bonded thereto; and R7 is independently a hydrogen atom or a benzoyl group).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a compound having a novel quinolinecarboxamide skeleton, which exhibits excellent antibacterial activity.

[0002]

2. Description of the Related Art Resistant Gram-positive bacteria such as MRSA (methicillin-resistant Staphylococcus aureus) and VRE (vancomycin-resistant enterococcus) are resistant to treatment with existing antibacterial agents. Therefore, development of an antibacterial agent having a strong antibacterial activity against such resistant Gram-positive bacteria is desired. So far
Although antibacterial compounds having various chemical structures are known, antibacterial compounds having a quinolinecarboxamide skeleton have not been known so far.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel antibacterial agent having a quinolinecarboxamide skeleton.

[0004]

The present invention relates to a compound having a quinolinecarboxamide skeleton represented by the following formula (I) or a salt thereof.

[0005]

[Chemical 4]

(Wherein R ₁ is a pyridyl group, a pyrazyl group,
A pyrazole group, a quinolyl group, or an isoquinolyl group, R ₂ , R ₃ , R ₄ and R _{5 each} independently represent a hydrogen atom, a halogen atom, a nitro group or a hydroxyl group;
₆ is a lower alkyl group, a lower alkenyl group, or an aralkyl group, or R ₅ and R ₆ together form a heterocycle with the carbon atom and the nitrogen atom to which they are bonded. Often, R ₇ is independently a hydrogen atom or a benzoyl group, provided that when R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₇ are hydrogen atoms, R ₆ is methyl. Not a group, ethyl, butyl or propyl. )

The present invention also relates to a pharmaceutical composition such as an antibacterial agent characterized by containing a compound having a quinolinecarboxamide skeleton represented by the following formula (I) or a salt thereof.

[Chemical 5] (In the formula, R ₁ is a pyridyl group, a pyrazyl group, a pyrazole group, a quinolyl group, or an isoquinolyl group, and R ₂ ,
R ₃ , R ₄ and R ₅ are independently a hydrogen atom, a halogen atom, a nitro group or a hydroxyl group, R ₆ is a lower alkyl group, a lower alkenyl group or an aralkyl group, or R ₅ and , R _{6 taken} together may form a heterocycle with the carbon atom and the nitrogen atom to which they are attached, and R ₇ is independently a hydrogen atom or a benzoyl group. )

The present invention also provides a method for producing a compound having a quinolinecarboxamide skeleton or a salt thereof, which comprises the following formula (II):

[0009]

[Chemical 6]

(Wherein R is a lower alkyl group,
R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are as defined above. ) Is reacted with a compound represented by the following formula (III), R ₁ —NH ₂ (III) (wherein R ₁ is as defined above). And on how to.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
A compound having a quinolinecarboxamide skeleton of the present invention or a salt thereof (hereinafter, simply referred to as "compound of the present invention")
Is a compound having a novel chemical structure. The compounds of the present invention can form salts such as sodium salts. The compounds of the present invention show strong antibacterial activity against Gram-positive bacteria. Further, the present invention shows strong antibacterial activity against resistant Gram-positive bacteria. Unless otherwise stated herein, the following terms have the following meanings. The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. The pyridyl group, pyrazyl group, pyrazole group, quinolyl group, or isoquinolyl group may be substituted with any substituent as long as it does not affect the antibacterial properties of the compound. Examples of such a substituent include a lower alkyl group and
A halogen atom, a cyano group, etc. are included.

The lower alkyl group is a saturated alkyl group having 1 to 8, preferably 1 to 5, and more preferably 1 to 3 carbon atoms, which may be linear or branched. Good. Specifically, as the lower alkyl group, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert
-Lower alkyl groups such as butyl group and pentyl group are preferred. The lower alkyl group may be substituted with any substituent as long as it does not affect the antibacterial properties of the compound. Examples of such a substituent include a halogen atom.

The lower alkenyl group corresponds to a lower alkyl group, contains one double bond, and is an unsaturated aliphatic group. As such a lower alkenyl group, 1 to 8
An alkenyl group having 1 to 5, preferably 1 to 5 and more preferably 1 to 3 carbon atoms, which may be linear or branched. Specifically, examples of the lower alkenyl group include a vinyl group, a lower alkenyl group such as an n-propenyl group, an isopropenyl group, an n-butenyl group, an isobutenyl group, a sec-butenyl group, a tert-butenyl group or a pentenyl group. A group is preferably mentioned. The lower alkenyl group may be substituted with any substituent as long as it does not affect the antibacterial properties of the compound. Examples of such a substituent include a halogen atom.

The aralkyl group is an arylalkyl group, which is an alkyl group substituted with an aryl group. Here, the aryl group is, for example, a phenyl group, a naphthyl group, or the like. The alkyl group is as described above.
Specific examples of the aralkyl group include a benzyl group and the like. The aralkyl group, in the aryl group, within a range that does not affect the antibacterial property of the compound,
It may be substituted with any substituent. Examples of such a substituent include a halogen atom, an alkyl group, a lower alkoxy group, and the like.

The benzoyl group may be substituted with an alkanoyl group, a halogen atom, a lower alkoxy group or the like. The benzene ring may be substituted with any substituent as long as it does not affect the antibacterial properties of the compound. Examples of such a substituent include a halogen atom, an alkyl group, a lower alkoxy group, and the like.

The alkanoyl group is an acyl group derived from alkanoic acid. The alkyl group bonded to the carbonyl group includes a linear or branched alkyl group. Examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group or a lower alkyl group such as a pentyl group. In addition, decyl group and higher alkyl groups such as dodecyl group, tridecyl group and undecyl group are included. In addition, such an alkyl group may be substituted with an arbitrary substituent within a range that does not affect the antibacterial property of the compound. Examples of such a substituent include a halogen atom.

A lower alkoxy group is an alkoxy group consisting of an oxygen atom bonded to a lower alkyl group. The lower alkyl group constituting the lower alkoxy group is the same as the above lower alkyl group. As a lower alkoxy group,
For example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-
Examples thereof include linear or branched lower alkoxy groups such as butoxy group, tert-butoxy group and pentyloxy group. In addition, the lower alkyl group constituting the lower alkoxy group may be substituted with an arbitrary substituent as described above, as long as it does not affect the antibacterial property of the compound. Examples of such a substituent include a halogen atom.

R ₅ and R ₆ may be taken together to form, together with the carbon atom and the nitrogen atom to which these substituents are bonded, a heterocycle containing the carbon atom and the nitrogen atom. Such heterocycles include those with 5 or 6 membered rings,
It may contain a double bond. Examples of such a heterocycle include a 6-membered heterocycle, specifically, a pyridyl group, a dihydropyridyl group, a tetrahydropyridyl group and the like. In other words, R ₅ and R ₆ are taken together to form, for example, an aliphatic group which may have a double bond, and both ends of which are the carbon atom to which R ₅ and R ₆ are bonded, or It may combine with a nitrogen atom to form a heterocycle. Examples of the divalent group formed by R ₅ and R ₆ together include a propylene group. This propylene group is bonded to the carbon atom and the nitrogen atom to which R ₅ and R ₆ are bonded to form a dihydropyridine ring as a condensed ring.

The compound (I) of the present invention is basically prepared according to J.
Org. Chem. 41, 825 (1976), J. Heterocyclic Ch
It can be synthesized according to the synthetic method described in em. Volume 16, 1605 (1979), Volume 18, 917 (1981). For example, it can be synthesized according to the following scheme 1.

[0020]

Embedded image Scheme 1

Explaining in accordance with Scheme 1, for example,
Compound (IV) is dissolved in a solvent such as DMSO or DMF, treated with a base such as sodium hydride, and then R ₆ -X
(X represents iodine or a halogen atom such as a bromine atom)
The compound (V) in which the nitrogen atom is alkylated (R ₆ ) can be obtained by reacting with such an alkyl halide, alkenyl halide or aralkyl halide.

The compound (V) is then added to a reaction solution obtained by treating diethyl malonate with sodium hydride or the like in a solvent such as DMF, and heating at about 110 ° C.
A compound (II) having a 2-quinolone-3-carboxylate skeleton can be obtained. This compound (II) is then mixed with an amine such as R ₁ —NH ₂ (III) and heated, for example, at around 150 ° C. to convert the compound (I) of the present invention into a crystalline compound. Obtainable.

In Scheme 1 above, the starting compound, compound (I), is a known compound and is easily available on the market or can be synthesized. Specific examples of the compound of the present invention are shown in Table 1 below.

[0024]

[Table 1] Table 1 Compound number R ₁ R ₂ R ₃ R ₄ R ₅ R ₆ R ₇ 1 2-Py H H H H -CH ₂ CH = CH ₂ H 2 2-Py H H H H -CH ₂ CH = CH ₂ H (sodium salt) 3 2-Py H H H H -CH ₂ CH = CH ₂ H (potassium salt) 4 2-Py H H H H Me H 5 2-Py H H H H Et H 62 -Py H H H H n-Pro H 7 2-Py H H H H n-Bu H 8 2-Py H H H H iso-Pro H 9 2-Py H F H H -CH ₂ CH = CH ₂ H 10 2-Py H F F H -CH ₂ CH = CH ₂ H 11 2-Py H NO ₂ H H -CH ₂ CH = CH ₂ H 12 2-Py H H H H -CH ₂ CH = C (CH ₃ ) ₂ H 13 3-Py H H H H -CH ₂ CH = CH ₂ H 14 4-Py H H H H -CH ₂ CH = CH ₂ H 15 2-Py H H H H benzyl group H 16 3- ( _{2-chloro) H H H H -CH 2 CH} = CH 2 H Py 17 3- (2- _{chloro) H H H H -CH 2 CH} = CH 2 H -5- triflic Oro Methyl) Py 18 2-Pr H H H H -CH ₂ CH = CH ₂ H 19 2-Pr H F H H -CH ₂ CH = CH ₂ H 20 2-Pr H F F H -CH ₂ CH = CH ₂ H 21 2-Pr H Cl H H -CH 2 CH = CH 2 H 22 2-Pr H OH H H -CH 2 CH = CH 2 H 23 2-Pr H NO 2 H H -CH 2 CH = CH 2 H 24 2-Pr H Cl H ----- A ----- H 25 1-Iq H H H H -CH ₂ CH = CH ₂ H 26 3-Pz H H H H -CH ₂ CH = CH ₂ H 27 3- _{(4-cyano) H H H H -CH 2 CH} = CH 2 H -Pz 28 2-Pr H H H H -CH 2 CH = CH 2 benzoyl group

Here, Py represents a pyridyl group, and Pr
Represents a pyrazyl group, Pz represents a pyrazole group,
Iq represents an isoquinolyl group, Me represents a methyl group, Et represents an ethyl group, Pro represents a propyl group, and Bu represents a butyl group. Also, A is -CH ₂ CH = C
A divalent group represented by H- is shown. Regarding the compounds of the above specific examples, NMR data of the obtained compounds are shown in Tables 2 and 3 below.

[0026]

[Table 2] Table 2 Compound name ¹ H NMR (CDCl ₃ ) δ value 1 4.97 (2H), 5.23 (1H), 5.27 (1H), 6.00 (1H), 7.10 (1H), 7.26-7.41 (3H), 7.60-7.78 (2H), 8.15-8.40 (2H), 8.41 (1H), 12.97 (1H) 4 3.75 (3H), 7.08 (1H), 7.26-7.42 (3H), 7.65-7.82 (2H), 8.15- 8.32 (2H), 8.41 (1H), 13.02 (1H) 5 1.38 (3H), 4.39 (2H), 7.07 (1H), 7.26-7.43 (3H), 7.68-7.70 (2H), 8.20-8.41 (2H) , 8.42 (1H), 13.09 (1H) 6 1.04 (3H), 1,73-1.87 (2H), 4.28 (2H), 7.08 (1H), 7.26-7.40 (4H), 7.73 (1H), 8.28 (1H ), 8.72 (2H), 13.54 (1H) 7 1.02 (3H), 1.44-1.69 (2H), 1.69-1.81 (2H), 4.31 (2H), 7.08 (1H), 7.26-7.41 (4H), 7.73 ( 1H), 8.28 (1H), 8.72 (2H), 13.54 (1H) 8 1.67 (3H), 1.69 (3H), 5.56 (1H), 7.08 (1H), 7.26-7.34 (3H), 7.56-7.73 (2H ), 8.29 (1H), 8.72 (2H), 13.56 (1H) 9 4.96-4.97 (2H), 5.12 (1H), 5.26 (1H), 5.95 (1H), 7.09 (1H), 7.25-7.46 (3H) , 7.75 (1H), 7.93 (1H), 8.22 (1H), 8.41 (1H), 12.94 (1H) 10 4.89-4.92 (2H), 5.14 (1H), 5.29 (1H), 5.94 (1H), 7.06- 7.18 (2H), 7.26 (1H), 7.75 (1H), 8.03 (1H), 8.20 (1H), 8.40 (1H), 12.78 (1H) 11 5.00-5.03 (2H), 5.15 (1H), 5.31 (1H ), 5.97 (1H), 7.12 (1H), 7.26 (1H), 7.45 (1H), 7.80 (1H), 8.22 (1H), 8.42 (1H), 8.49 (1H), 12.60 (1H) 12 1.74 (3H), 1.91 (3H), 4.94-4.97 (2H), 5.15 (1H), 7.07 (1H ), 7.26-7.36 (4H), 7.65-7.77 (2H), 8.20-8.28 (2H), 8.41 (1H), 13.03 (1H) 13 4.97-4.99 (2H), 5.11 (1H), 5.28 (1H), 6.00 (1H), 7.26-7.38 (5H), 7.70 (1H), 8.20-8.30 (2H), 8.83 (1H), 12.65 (1H) 14 4.96-4.98 (2H), 5.10 (1H), 5.28 (1H) , 6.01 (1H), 7.26-7.39 (3H), 7.63-7.75 (3H), 8.29 (1H), 8.55-8.57 (2H), 12.79 (1H) 15 5.58 (2H), 7.08 (1H), 7.23-7.34 (8H), 7.58 (1H), 7.74 (1H), 8.21-8.39 (2H), 8.40 (1H), 13.00 (1H) 16 4.99-5.09 (2H), 5.15 (1H), 5.26 (1H), 5.98 ( 1H), 7.26-7.38 (4H), 7.69 (1H), 8.16 (1H), 8.26 (1H), 8.81 (1H), 13.04 (1H) 17 4.99-5.01 (2H), 5.13 (1H), 5.27 (1H) ), 5.99 (1H), 7.26-7.38 (3H), 7.72 (1H), 8.01 (1H), 8.29 (1H), 8.72 (1H), 13.68 (1H) 18 4.97-4.99 (2H), 5.13 (1H) , 5.26 (1H), 5.98 (1H), 7.26-7.38 (4H), 7.70 (1H), 8.28 (1H), 8.35-8.38 (2H), 9.56 (1H), 13.09 (1H) 19 4.96-4.98 (2H ), 5.12 (1H), 5.28 (1H), 5.97 (1H), 7.26-7.37 (2H), 7.42 (1H), 7.92 (1H), 8.35-8.39 (2H), 9.56 (1H), 13.05 (1H) 20 4.90-4.92 (2H), 5.14 (1H), 5.31 (1H), 5.92 (1H), 7. 16 (1H), 7.27 (1H), 8.05 (1H), 8.36-8.40 (2H), 9.55 (1H), 12.89 (1H) 21 4.95-4.97 (2H), 5.11 (1H), 5.27 (1H), 5.96 (1H), 7.26-7.32 (4H), 7.63 (1H), 8.24 (1H), 8.35-8.40 (2H), 9.56 (1H), 12.98 (1H) 23 5.01-5.03 (2H), 5.15 (1H), 5.32 (1H), 5.93 (1H), 7.47 (1H), 8.38 (1H), 8.42 (1H), 8.52 (1H), 9.16 (1H), 9.57 (1H), 12.70 (1H) 24 1.52 (3H), 1.54 (3H), 6.24 (1H), 6.35 (1H), 7.33 (1H), 7.60 (1H), 8.21 (1H), 8.35-8.39 (2H), 9.55 (1H), 12.83 (1H) 25 5.03-5.05 (2H), 5.16 (1H), 5.29 (1H), 6.00 (1H), 7.26-7.40 (3H), 7.55 (1H), 7.67-7.77 (3H), 7.86 (1H), 8.29-8.34 (2H), 8.50 (1H), 13.61 (1H) 26 4.96 (2H), 5.10 (1H), 5.31 (1H), 5.97 (1H), 6.52 (1H), 7.23-7.36 (3H), 7.55 (1H), 7.68 (1H) ), 8.26 (1H), 12.82 (1H) 28 4.77-4.90 (2H), 5.00 (1H), 5.18 (1H), 5.83 (1H), 7.22-7.40 (2H), 7.46-7.79 (7H), 8.22- 8.33 (3H), 8.83 (1H)

[0027]

[Table 3] Table 3 Compound name Melting point (° C) ¹ H NMR (DMSO-d ₆ ) δ value 22 4.92-5.18 (4H), 5.94 (1H), 7.28 (1H), 7.43 (2H), 8.46 (2H) , 9.41 (1H), 9.96 (1H), 13.25 (1H) 27 4.97-5.18 (5H), 5.97 (1H), 7.42 (1H), 7.59 (1H), 7.83 (1H), 8.15-8.18 (2H), 8.62 (1H), 12.60 (1H), 13.69 (1H)

The compounds of the present invention can be used as salts. Such salts include, for example, salts of alkali metals (such as sodium and potassium) and alkaline earth metals (such as calcium and magnesium). The compound of the present invention is an antibacterial agent useful for treating local infections of humans and animals caused by gram-positive bacteria, resistant gram-positive bacteria and the like, and systemic infections. Examples of Gram-positive bacteria include Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Enterococcus faecium, Streptococcus pyogenes, and the like. The compound of the present invention is also effective against these resistant bacteria such as mesicillin-resistant Staphylococcus aureus.

The compound of the present invention may be used alone or in combination with a pharmaceutically acceptable adjuvant, diluent, binder, etc.
For example, it can be used in the form of general pharmaceutical compositions such as tablets, dragees, capsules, injections, creams, ointments, solutions, powders and the like. The compounds of the present invention can be used alone or as a mixture of a plurality of different compounds. In the case of injectables, solubilizers or solubilizers (eg, distilled water for injection, physiological saline, propylene glycol, etc.) that can form an aqueous or in-use dissolution type dosage form, pH adjusters (eg, inorganic or Pharmaceutical components such as organic acids or bases), isotonicity agents (eg, salt, glucose, glycerin, etc.), stabilizers and the like are used.

In the case of oral agents, excipients (eg lactose, D-mannitol, corn starch, crystalline cellulose etc.), disintegrants (eg carboxymethyl cellulose, carboxymethyl cellulose calcium etc.), binders (eg hydroxy) Propylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone etc.), lubricants (eg magnesium stearate, talc etc.), coating agents (eg hydroxypropylmethylcellulose, sucrose, titanium oxide etc.), plasticizers (eg polyethylene glycol etc.) ), A base (for example, polyethylene glycol, hard fat, etc.) and the like, are used. In addition, for external preparations, for example, ointments, creams, and formulation components suitable for patches (eg, white petrolatum, macrogol, glycerin, liquid paraffin, cotton cloth, etc.) are used.

The compound of the present invention varies depending on, for example, symptoms, age, body weight, etc., but in the case of systemic administration, it is usually
0.1 to 100 mg, preferably 0.5 to 30 mg can be administered. On the other hand, the concentration of the active ingredient in topical treatment is, for example, 0.1 to 20% by mass, and preferably,
The optimum amount is 0.5 to 10% by mass. Of course, the compounds of the invention can be used as germicides. In such a case, the compound of the present invention is, for example, 0.01 to 10% by mass in a medium such as water or ethanol.
Preferably, it can be used in an amount of 0.05 to 5% by mass. The compound of the present invention can be used not only in the medical field but also in the field of agricultural chemicals.

The present invention will be described in more detail with reference to Examples and Reference Examples, but the scope of the present invention is not limited to these Examples and Reference Examples.

Synthesis Example 1

[0034]

[Chemical 8]

Sodium hydride washed with 15 ml of n-hexane-60% DMF (1.35 g) in mineral oil (125 m
l) To the suspension, 1-bromopropene (6.49 ml) was added, and the mixture was stirred at room temperature for 30 minutes, then benzoxazinedione (5
g) was added, and the mixture was further stirred at room temperature for 2 hours. The solvent was evaporated under reduced pressure, water was added to the residue, and the mixture was extracted 3 times with chloroform. After the chloroform layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure. Ethanol was added to the residue, and the resulting crystalline powder was collected by filtration to obtain 5.67 g of benzoxazine-2,4- (1-allyl) -dione. Synthesis example 2

[0036]

[Chemical 9]

Sodium hydride washed with 25 ml n-hexane-60% DMF (2.23 g) in mineral oil (140 ml)
Diethyl malonate (8.47 ml) was added to the suspension under ice cooling,
Benzoxazine-2,4- (1-allyl) -dione (5.67g) was then added. The reaction mixture was stirred at 110 ° C. for 2 hours, the solvent was evaporated under reduced pressure, ice water and then chloroform were added to the residue for extraction. The aqueous layer was separated, acidified with concentrated hydrochloric acid and then extracted with chloroform. The organic layer was washed with water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Diisopropyl ether was added to the residue, the resulting crystalline powder was collected by filtration, and 5.9 g of ethyl 1-allyl-
1,2-dihydro-4-hydroxy-2-oxo-3-
Quinoline carboxylate was obtained. Example 1

[0038]

[Chemical 10]

Ethyl 1-allyl-1,2-dihydro-
4-hydroxy-2-oxo-3-quinolinecarboxylate (104 mg) and 2-aminopyridine (37 m
The mixture with g) was stirred at 150 ° C. for 30 minutes. The resulting crystals were recrystallized from chloroform to obtain 94 mg of 1-allyl-1,2-dihydro-4-hydroxy-2-oxo-N-pyridyl-3-quinolinecarboxamide.
The compounds of the present invention described in Table 1 above were synthesized according to the above Synthesis Examples and Examples.

Test Example 1 Antibacterial Test Method (Measurement of Minimum Inhibitory Concentration, MIC) Japanese Society of Chemotherapy Standard Method [Chemotherapy 38: 102 (1990)]
According to the above, MIC (unit: μg / ml) was measured after culturing for 20 hours at 35 ° C. by a trace amount liquid dilution method using a Mueller Hinton medium to which calcium ions and magnesium ions were added. The results are shown in Table 4 below. The compound numbers used are as described in Table 1 above.

[0041]

[Table 4] Table 4

As can be seen from the data shown in Table 4 above, the compounds of the present invention have excellent antibacterial activity against Gram-positive bacteria as well as resistant Gram-positive bacteria.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yutaka Maeda             3-14, Masuo, Kashiwa City, Chiba Prefecture (72) Inventor Toshio Yoshida             4-6-3 Koshiba, Ryugasaki City, Ibaraki Prefecture             Room 301 (72) Inventor Mitsuko Nakajima             2-10 Sanuki, 3-10 Sanuki, Ryugasaki City, Ibaraki Prefecture             Room E (72) Inventor Hiroto Hara             1-17-1 Kannondai, Tsukuba City, Ibaraki Prefecture             Room 206 (72) Inventor Kazuki Yokose             Chiba Prefecture Urayasu City Negomi 3-chome 19-16 F-term (reference) 4C063 AA01 BB09 CC14 CC15 CC22                       CC34 DD12 DD14 EE01                 4C086 AA01 AA02 AA03 AA04 BC28                       BC30 BC35 BC48 GA07 GA08                       MA01 MA04 NA14 ZB35

Claims (4)

[Claims] 1. A compound having a quinolinecarboxamide skeleton represented by the following formula (I) or a salt thereof. [Chemical 1] (In the formula, R ₁ is a pyridyl group, a pyrazyl group, a pyrazole group, a quinolyl group, or an isoquinolyl group, and R ₂ , R ₃ , R _4, and R ₅ are independently a hydrogen atom, a halogen atom, or a nitro group. Or a hydroxyl group, R ₆ is a lower alkyl group, a lower alkenyl group, or an aralkyl group, or R ₅ and R ₆ together form a carbon atom and a nitrogen atom to which they are bonded, A heterocycle may be formed, and R ₇ is independently a hydrogen atom or a benzoyl group, provided that R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₇ are hydrogen atoms. R ₆ is a methyl group, an ethyl group, a butyl group,
And not a propyl group. ) 2. A pharmaceutical composition comprising a compound having a quinolinecarboxamide skeleton represented by the following formula (I) or a salt thereof. [Chemical 2] (In the formula, R ₁ is a pyridyl group, a pyrazyl group, a pyrazole group, a quinolyl group, or an isoquinolyl group, and R ₂ , R ₃ , R _4, and R ₅ are independently a hydrogen atom, a halogen atom, or a nitro group. Or a hydroxyl group, R ₆ is a lower alkyl group, a lower alkenyl group, or an aralkyl group, or R ₅ and R ₆ together form a carbon atom and a nitrogen atom to which they are bonded, A heterocycle may be formed, and R ₇ is independently a hydrogen atom or a benzoyl group.) 3. The pharmaceutical composition according to claim 2, which is an antibacterial agent. 4. A method for producing a compound having a quinolinecarboxamide skeleton or a salt thereof according to claim 1, which comprises the following formula (II): (Wherein R is a lower alkyl group, and R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are as defined above), and the compound (II) represented by the following formula (III ), R ₁ —NH ₂ (III) (wherein R ₁ is as defined above).