JPH0234324B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to antibacterial agents, more specifically, 7-(3
-amino-1-pyrrolidinyl)-1-(2,4-difluorophenyl)-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3
- An antibacterial agent comprising a carboxylic acid (hereinafter referred to as compound A) or an acid addition salt thereof and an organic acid having 2 to 6 carbon atoms. [Prior Art] Compound A or its acid addition salt is a novel compound that has a strong antibacterial effect against Gram-positive bacteria and Gram-negative bacteria, especially against antibiotic-resistant bacteria. JP-A No. 60-228479 discloses that no antibacterial agent is known which is composed of Compound A or its acid addition salt and an organic acid having 2 to 6 carbon atoms. [Problems to be Solved by the Invention] An object of the present invention is to provide an antibacterial agent that improves the absorption of Compound A or its acid addition salt upon oral administration. [Means for Solving the Problems] As a result of intensive research to achieve the above object, the present inventors decided to blend an organic acid having 2 to 6 carbon atoms into Compound A or its acid addition salt. As a result, the inventors have discovered that the absorption of Compound A or its acid addition salt after oral administration is significantly improved, leading to the completion of the present invention. The present invention will be explained in detail below. The acid addition salt of Compound A can be used without particular limitation as long as it is a pharmaceutically acceptable salt; for example, hydrochloric acid, sulfuric acid, nitric acid,
Salts with mineral acids such as phosphoric acid, malonic acid, malic acid,
Examples include salts with carboxylic acids such as tartaric acid and citric acid, and salts with fulphonic acids such as methanesulfonic acid and p-toluenesulfonic acid. As the organic acid having 2 to 6 carbon atoms, any organic acid that can be used as a medicine can be used without particular limitation. Such examples include preferably dicarboxylic acids such as malonic acid, fumaric acid, oxycarboxylic acids such as glycolic acid, gluconic acid, tartaric acid, malic acid, citric acid, amino acids such as aspartic acid, glutamic acid, and ascorbic acid. Examples include acids. In addition, for organic acids having 2 to 6 carbon atoms, optical isomers,
Isomers such as racemates and geometric isomers may exist, and any of them are included in the present invention. The amount of the organic acid having 2 to 6 carbon atoms is not particularly limited, but usually 0.1 to 10 times the amount of compound A or its acid addition salt (in terms of weight) is sufficient. Also,
Two or more types of organic acids having 2 to 6 carbon atoms can also be blended. The present invention is carried out by uniformly mixing Compound A or its acid addition salt and an organic acid having 2 to 6 carbon atoms. The antibacterial agent of the present invention is used by formulating it into dosage forms commonly known for oral administration, such as tablets, capsules, granules, pills, fine granules, and powders. During formulation, commonly used additives such as excipients, surfactants, fillers, disintegrants, lubricants, and binders can be added as appropriate. In addition, the administration method, dosage, and frequency of administration of the antibacterial agent of the present invention can be appropriately selected depending on the patient's disease. Normally, for adults, 0.1 to 100 mg/Kg/day in terms of compound A is administered orally. It may be administered in one to several divided doses. Compound A or its acid addition salt used in the present invention can be produced, for example, according to the following production route. That is, 2,6-dichloro-5-fluoronicotinoyl acetic acid ethyl ester [V] obtained by reacting acid chloride of 2,6-dichloro-5-fluoronicotinic acid with diethyl ethoxymagnesium malonate and N,N- Reacting dimethylformamide dimethyl acetal and 2,4-difluoroaniline to produce 2-(2,6-dichloro-5-fluoronicotinoyl)-3-(2,4-difluorophenylamino)acrylic acid ethyl ester []
get. By heating the obtained compound of formula [] in the presence of a base such as sodium hydrogen carbonate, 7-chloro-6-fluoro-1-(2,4-
difluorophenyl)-1,4-dihydro-4-
Oxo-1,8-naphthyridine-3-carboxylic acid ethyl ester [ ] is obtained. The obtained compound of formula [ ] was reacted with 3-acetylaminopyrrolidine to give 7-(3-acetylamino-1-pyrrolidinyl)-1-(2,4-difluorophenyl)-6.
-Fluoro-1,4-dihydro-4-oxo-
1,8-naphthyridine-3-carboxylic acid ethyl ester [] is obtained, and then hydrolyzed to obtain 7-(3-amino-1-pyrrolidinyl)-1-(2,4-difluorophenyl) represented by the formula []. )−
6-Fluoro-1,4-dihydro-4-oxo-
1,8-naphthyridine-3-carboxylic acid (compound A) is obtained. The acid addition salt of Compound A can then be obtained by reacting with an acid to obtain precipitated crystals. [Effects of the Invention] Next, the antibacterial activity and acute toxicity of Compound A or its acid addition salt, as well as the dissolution test results and urinary recovery rate of the antibacterial agent of the present invention after oral administration, will be shown. (i) Antibacterial activity Test method Japanese Society of Chemotherapy Standard Method [CHEMOTHERAPY] Vol. 29 No. 1 No. 76-79
(1981)], a bacterial suspension cultured at 37°C for 20 hours in Heart Infusion broth (manufactured by Eiken Kagaku Co., Ltd.) was mixed with Heart Infusion broth containing the hydrochloride of compound A.
After inoculating agar (Heart Infusion agar) medium (manufactured by Eiken Chemical Co., Ltd.) and culturing at 37°C for 20 hours,
The presence or absence of bacterial growth was observed, and the minimum concentration at which bacterial growth was inhibited was defined as the MIC (μg/ml).
However, the amount of contact bacteria is 10 ⁴ pieces/plate (10 ⁶ pieces/plate)
ml). The results are shown below. The symbols used in the table have the meanings below. ※ Penicillinase-producing bacteria ※※ Cephalosporinase-producing bacteria

[Table] (ii) Acute toxicity test of the test compound described in (i) in mice (ICR type,
Male, weight 18-24 g) LD ₅₀ for intravenous administration
The value was over 200 mg/Kg. (iii) Dissolution test Powder or capsule contents equivalent to 100 mg of Compound A were added to 50 ml of water at 37°C with stirring (approx.
300 rpm) and eluted into water over time, Compound A was measured by high performance liquid chromatography (HPLC) under the conditions described below. The results are shown in Table-1. [HPCL measurement conditions Γ model: Shimazu LC-3A Γ column: Nucleosil ₁₀ C ₁₈ (250 mm) Γ column temperature: 35°C Γ measurement wavelength: 340 mm Γ mobile phase: acetonitrile: 0.2M citric acid 2
Sodium salt aqueous solution: water: 10% methanesulfonic acid-triethylamine aqueous solution = 5:6:
7:2 Γ flow rate: 1.5 ml/min Retention time of Γ compound A: approximately 6 minutes]

[Table] (iv) Initial dissolution test Compound A or its salt and anhydrous citric acid were each ground, and 20 mg of the same amount was physically mixed in 100 meshes, and 5 ml of 0.001N hydrochloric acid (PH3.0) and 1/15M phosphate buffer (PH
6.5) Add each to 5 ml and vertically
After mixing for 2 minutes with a mixer (Vortical mixer), it was filtered through a membrane filter with a pore size of 0.3 μm, and the compound A or its salt eluted in the solution was subjected to high performance liquid chromatography (HPLC) in the same manner as in (iii). It was measured with Table 2 shows the results.
Shown below.

【table】

[Table] (v) Urinary recovery rate 1 group of 3 female beagles weighing 8.0 to 9.7 kg
As a head, use the formulation shown in the formulation example (in the case of powder)
It was suspended in a 0.5% methylcellulose aqueous solution and administered orally using a sonde (or as it is in the case of capsules). The dose is 100 per animal as compound A.
mg. After administration, the animals are placed in a cage, water is given ad libitum, and urine is collected for up to 24 hours. Quantification of Compound A in urine was performed using Escherichia coli (E.coli).
The amount of Compound A excreted into the urine was determined from urea and the urea concentration, and the urinary recovery rate relative to the dose was calculated. The results are shown in Table 3.

[Table] As is clear from Tables 1 to 3, the antibacterial agent of the present invention significantly improves the oral absorption of Compound A. [Examples] Next, formulation examples and reference examples of the present invention will be described, but the present invention is not limited thereto. Formulation example 1 10g of citrate of compound A and 10g of anhydrous citric acid
Mix and pass through a 42-mesh standard sieve to remove the powder.
Obtain 19.5g. Formulation Example 2 Mix 10 g of citrate of compound A and 10 g of fumaric acid, pass through a 42 mesh standard sieve, and obtain 19.0 g of powder.
get. Formulation Example 3 50 g of p-toluenesulfonate of Compound A and 50 g of anhydrous citric acid are mixed, passed through a 24-mesh standard sieve, and further mixed with 1 g of magnesium stearate. This was placed in No. 4 capsules (manufactured by Nippon Elanco) with 100 mg per capsule (containing 50 mg of p-toluenesulfonate of compound A).
Fill it to obtain about 980 No. 4 capsules. Formulation Example 4 100 g of p-toluenesulfonate of Compound A and 100 g of fumaric acid are mixed and passed through a 24-mesh standard sieve. This was placed in No. 3 capsules (manufactured by Nippon Elanco) with approximately 200 mg per capsule (p-
Contains 100mg of toluene sulfonate),
Obtain 960 capsules of No. 3 capsules. Formulation example 5 p-toluenesulfonate of compound A 10g and L
- Mix with 10 g of glutamic acid and pass through a 42-mesh standard sieve to obtain 19.0 g of powder. Formulation Example 6 10 g of p-toluenesulfonate of Compound A and 10 g of tartaric acid were mixed and passed through a 42 mesh standard sieve to obtain 18.5 g of powder. Formulation Example 7 10 g of p-toluenesulfonate of Compound A and 10 g of malonic acid were mixed and passed through a 42-mesh standard sieve to obtain 19.5 g of powder. Formulation Example 8 10 g of p-toluenesulfonate of Compound A and 10 g of ascorbic acid were mixed and passed through a 42-mesh standard sieve to obtain 20 g of a powder. Formulation example 9 Mix 10 g of compound A and 10 g of anhydrous citric acid,
Pulverize the entire product in a mortar so that it can pass through a 100-mesh standard sieve and use it as a tablet powder. One tablet per tablet
Compress 600 mg using a flat punch with a diameter of 15 mm at a main pressure of 3 tons to obtain 20 tablets. The obtained tablets were passed through a 42-mesh standard sieve in a mortar to obtain 18 g of powder. Formulation example 10 p-toluenesulfonate of compound A 50g, L
- 25 g of aspartic acid, 5.5 g of cornstarch and 6.8 g of Avicel PH102 [manufactured by Asahi Kasei Industries, Ltd.]
After mixing for 30 minutes using a mold mixer, the mixture is kneaded with a 7% aqueous solution of hydroxypropyl methyl cellulose [manufactured by Shin-Etsu Chemical Co., Ltd.] [HPC-SL] using a kneader. Then, the mixture was dried by blowing air at 40°C overnight. After drying, the particles were sized using a power mill (Okada Seiko 20 mesh) and Ad Solider 02 (SiO ₂ : Freund) 5
g, cornstarch 17.5 and Avicel PH302
Add 7.5 g [manufactured by Asahi Kasei Industries, Ltd.] and mix for 30 minutes using a V-type mixer. Furthermore, 1.2 g of magnesium stearate is added and mixed for 2 minutes to form a tablet powder. The tablets were compressed at 120 mg per tablet (containing 50 mg of p-toluenesulfonate of compound A) using a flat punch with a diameter of 6.5 mm and a main pressure of 1.45 tons.
Get 800 tablets. Properties of the obtained tablet Hardness: 8 to 10 kg Disintegration (water): 1 minute to 1 minute 30 seconds Weight: 117 to 124 mg/Tablet Formulation Example 11 300 g of compressed tablet powder similar to Formulation Example 10 was placed in a capsule filling machine (Robert GKF-120 (manufactured by Botsuyu Co., Ltd.) was used to fill No. 5 capsules (manufactured by Nippon Elanco) with 120 mg per capsule to obtain about 2,000 capsules in No. 5 capsules. Disintegration of properties of the obtained capsules (pharmacopoeia first liquid): 2 to 3 minutes Weight (capsule weight included): 148 to 155 mg/capsule reference example 1 (1) 2,6-dichloro-5-fluoronicotinic acid
21 g was dissolved in 210 ml of chloroform, 23.8 g of thionyl chloride and 0.1 g of N,N-dimethylformamide were added, and the mixture was reacted at 70°C for 2 hours.
The solvent and excess thionyl chloride were distilled off under reduced pressure, and the resulting residue was dissolved in 21 ml of tetrahydrofuran.
Dissolve in. Ethoxymagnesium diethyl malonate prepared from 2.67g of magnesium 25.1
Dissolve g in 110 ml of tetrahydrofuran, -40
Cool to ~-30°C. Add the previously prepared tetrahydrofuran solution of 2,6-dichloro-55-fluoronicotinic acid chloride to this solution at the same temperature.
It takes 30 minutes to drip. After stirring this mixed solution at the same temperature for 1 hour, the temperature is gradually raised to room temperature. The solvent was distilled off under reduced pressure, and 200 ml of chloroform and 100 ml of water were added to the resulting residue to give 6N-
Adjust the pH to 1 with hydrochloric acid. Separate the organic layer and add 50% water
ml, 50 ml of 5% aqueous sodium bicarbonate solution, and 50 ml of saturated saline solution, and then dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, 50 ml of water and 0.15 g of p-toluenesulfonic acid were added to the obtained oil, and the mixture was reacted at 100°C for 2 hours with vigorous stirring.
Extract with 100ml. The organic layer was washed with 50 ml of saturated brine, dried over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure, and the resulting residue was subjected to column chromatography (Wako silica gel C-
200, eluent; toluene), the melting point
23.5 g of 2,6-dichloro-5-fluoronicotinoylacetic acid ethyl ester having a temperature of 64-65°C is obtained. IR (KBr) cm ^-1 ; ν _C=0 1650, 1630, 1620 NMR (CDCl ₃ ); δ value 1.25 (1.29H, t, J=7Hz), 1.33 (1.71H,
t, J=7Hz), 4.07 (1.14H, s), 4.28
(2H, q, J=7Hz), 5.82 (0.43H, s),
7.80 (1H, d, J = 7 Hz), 12.62 (0.43, s) (2) Dissolve 8.8 g of 2,6-dichloro-5-fluoronicotinoyl acetic acid ethyl ester in 40 ml of benzene, and dissolve N,N-dimethylformamide. Add 4.5 g of dimethyl acetal and react at 70°C for 1.5 hours. Next, 4.1 g of 2,4-difluoroaniline was added to this reaction solution, and the mixture was reacted at room temperature for 4 hours, and then the solvent was distilled off under reduced pressure. The resulting residue was subjected to column chromatography (Wako silica gel C-200, eluent: chloroform)
2-(2,
6-dichloro-5-fluoronicotinoyl)-
9.0 g of 3-(2,4-difluorophenylamino)acrylic acid ethyl ester are obtained. IR (KBr) cm ^-1 ; ν _C=0 1690 NMR (CDCl ₃ ); δ value 1.08 (3H, t, J=7Hz), 4.10 (2H, q,
J=7Hz), 6.77-7.40 (4H, m), 8.50 (1H,
d, J = 13Hz), 12.70 (1H, d, J = 13Hz) (3) 2-(2,6-dichloro-5-fluoronicotinoyl)-3-(2,4-difluorophenylamino)acrylic acid 9.0g of ethyl ester in N,
Dissolve in 90 ml of N-dimethylformamide, add 3.6 g of sodium hydrogen carbonate, and react at 120°C for 20 minutes. Then, the solvent is distilled off under reduced pressure, and the resulting residue is dissolved in 50 ml of chloroform. Mix this reaction solution with 30ml of water and saturated saline.
After sequentially washing with 30 ml, dry with anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting crystalline material was washed with 30 ml of diethyl ether to give 7-chloro-6-, which had a melting point of 220-222°C.
Fluoro-1-(2,4-difluorophenyl)-
1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid ethyl ester 7.0
get g. IR (KBr) cm ^- ₁ ; ν _C=0 1730, 1690 NMR (CDCl ₃ ); δ value 1.36 (3H, t, J=7Hz), 6.30 (2H, q,
J=7Hz), 6.80-7.60 (3H, m), 8.27 (1H,
d, J = 7Hz), 8.42 (1H, s) (4) 7-chloro-6-fluoro-1-(2,4-
difluorophenyl)-1,4-dihydro-4
-0.50 g of oxo-1,8-naphthyridine-3-carboxylic acid ethyl ester in 5 ml of chloroform.
0.20 g of 3-acetylaminopyrrolidine and 0.15 g of tolylethylamine were added thereto, and the mixture was reacted at 60°C for 1 hour. Then, the solvent was distilled off under reduced pressure, and the resulting residue was subjected to column chromatography [Wako Silica Gel C-200,
Eluent; chloroform:ethanol = 30:1
(volume ratio)], 7-(3-acetylamino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4- dihydro-4-oxo-
0.50 g of 1,8-naphthyridine-3-carboxylic acid ethyl ester is obtained. IR (KBr) cm ^-1 ; ν _C=0 1725, 1700 NMR (CDCl ₃ ); δ value 1.32 (3H, t, J=7Hz), 1.77~2.27 (m) 2.08 (S) (5H), 3.12~ 3.74 (4H, m), 4.02 ~ 4.74 (m) 4.29 (q, J = 7Hz) (3H), 6.75 ~ 7.60 (4H, m), 7.93 (1H, d, J = 8Hz),
8.24 (1H, s) (5) 7-(3-acetylamino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4-dihydro-4-oxo-
0.25 g of 1,8-naphthyridine-3-carboxylic acid ethyl ester is dissolved in 2.5 ml of 6N hydrochloric acid and reacted under reflux for 2 hours. Then, the reaction solution was cooled to room temperature, adjusted to pH 12 with 1N aqueous sodium hydroxide solution, and then adjusted to pH 6.5 with acetic acid. The precipitated crystals are collected, washed with 2 ml of water, and dried to give 7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4- dihydro-4-
0.18 g of oxo-1,8-naphthyridine-3-carboxylic acid is obtained. NMR (TFA-d ₁ ); δ value 2.25-2.85 (2H, m), 3.37-4.69 (5H,
m), 6.93-7.81 (3H, m), 8.22 (1H, d,
J=11Hz), 9.16 (1H, s) Reference example 2 7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-
After dissolving 2.0 g of 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid in 20 ml of concentrated hydrochloric acid, 200 ml of ethanol was added at room temperature.
Stir for a minute. Remove the precipitated crystals and add 40ml of ethanol.
If washed with
-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4
1.4 g of hydrochloride of -dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid are obtained. IR (KBr) cm ^-4 ; ν _C=0 1730 Reference example 3 7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-
10.0 g of 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid was added to 5 ml of ethanol.
and suspend in 75 ml of water. To this was added 5.2 g of p-toluenesulfonic acid monohydrate at 40°C, and the mixture was stirred at the same temperature for 30 minutes. Then, after cooling the reaction solution to 15°C, the precipitated crystals are collected and washed with a mixed solvent of 5 ml of ethanol and 5 ml of water, resulting in a melting point of 258~
7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4-dihydro-4-oxo-1, which exhibits a temperature of 260°C.
12.8 g of p-toluenesulfonate monohydrate of 8-naphthyridine-3-carboxylic acid is obtained. IR (KBr) cm ^-1 ; ν _C=0 1735 In the same manner, the acid addition salt of Compound A shown in Table 4 is obtained.

【table】

Claims (1)

[Claims] 1 7-(3-amino-1-pyrrolidinyl)-1-
(2,4-difluorophenyl)-6-fluoro-
An antibacterial agent containing 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid or an acid addition salt thereof and an organic acid having 2 to 6 carbon atoms. 2. The antibacterial agent according to claim 1, wherein the organic acid is a dicarboxylic acid. 3. The antibacterial agent according to claim 1, wherein the organic acid is an oxycarboxylic acid. 4 Claim 1 in which the organic acid is an amino acid
Antibacterial agents listed in section.