JPH0570458A - Pyrroloquinoline quinone derivative - Google Patents

Abstract

PURPOSE:To obtain a new compound useful as medicines and agricultural chemicals. CONSTITUTION:A compound, e.g. 2,9-dimethoxycarbonyl-7-carboxy-4,5-dihydro-4,5- dioxo-1H-pyrrolo[2,3-f]quinoline expressed by formula I (R1 and R2 are H or methyl, except when both are simultaneously H and methyl). The compound expressed by formula I is obtained by partially hydrolyzing a compound expressed by formula II with, e.g. trifluoroacetic acid at 10-100 deg.C under acidic conditions for 1-24hr. The compound expressed by formula II is trimethyl ester of 4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f] quinol ine-2,7,9-tricarboxylic acid which is a coenzyme of methanol dehydrogenase. The compound expressed by formula II is used at a concentration within the range of 0.0001-10mM.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a novel pyrroloquinoline quinone (4,5-dihydro-4,5-dioxo-1H-
Pyrrolo [2,3-f] quinoline-2,7,9-tricarboxylic acid) dimethyl ester and salts thereof.

[0002]

2. Description of the Prior Art Methano
4,5-dihydro-4,5-dioxo-1H-, which was found as a coenzyme of methanol dehydrogenase of the assimilating bacterium
Pyrrolo [2,3-f] quinoline-2,7,9-tricarboxylic acid (or methoxatin, hereinafter referred to as PQQ) is
Since then, it has been found that not only bacteria but also fungi and yeasts of eukaryotes play an important role as coenzymes. Further, its physiological action is not limited to the action as a coenzyme, and is useful for microorganisms, plants and animals. For example, cell proliferation action (JP-A-61-58).
No. 584, No. 63-233783), anti-cataract action (Japanese Patent Laid-Open No. 63-41421, No. 63-48).
215, 64-29313), liver disease preventive and therapeutic action (JP-A-63-192717),
Wound healing action (JP-A-63-152309), anti-allergic action (JP-A-63-17493), reverse transcriptase inhibitory action (JP-A-63-156724),
JP-A-1-29313) and glyoxalase 1 inhibitory activity-anticancer activity (JP-A-63-215628, JP-A-1-29313) and the like are known.

However, PQQ has nephrotoxicity (Watanabe et al., Hioshima J. Med. Sci., Vol. 38, No. 1, 49-5).
, 1989), and its poor absorbability in vivo, there are difficulties in using it as a drug, and an agent to replace it is required. On the other hand, of the 7 possible compounds as a simple methyl ester form of PQQ, trimethyl ester (Du
ine et al., Eur. J. Biochem., 1980, 108, 187), a monoester in which only the carboxyl group at the 2-position is methylated (Oshiro et al., Chem. Exp., 1, 315, 1986) and positions 7 and 9 There are only three known dimethyl esters (JP-A-2-262581) in which the carboxyl group at the position is methylated.

[0004]

Means for Solving the Problems In view of the above circumstances, the present inventors have conducted various studies to obtain a novel methyl ester of PQQ, and as a result, the 2-position and the carboxyl group at the 7-position or 9-position have The present invention has been completed by finding that a novel methylated dimethyl ester compound can be efficiently synthesized. That is, the present invention relates to a novel pyrroloquinoline quinone derivative represented by Chemical formula 1 and a salt thereof.

[0005]

[Chemical 1] [However, in Chemical formula 1, R ₁ and R ₂ represent a hydrogen atom or a methyl group. However, the case where both are a hydrogen atom or a methyl group is excluded. More specifically, 2,9-dimethoxycarbonyl-7-carboxy-4,5-dihydro-4,
5-dioxo-1H-pyrrolo [2,3-f] quinoline (Compound No. 1) and 2,7-dimethoxycarbonyl-
It relates to 9-carboxy-4,5-dihydro-4,5-dioxo-1H-pyrrolo [2,3-f] quinoline (Compound No. 2), and salts thereof. Examples of such salts include alkali metal salts, alkaline earth metal salts and ammonium salts. The production method of the above compound is shown below. As shown in Chemical Formula 2 below, Compound 1 has a known PQ.
It can be produced by partially hydrolyzing Q trimethyl ester (Compound A) under acidic conditions.

[0006]

[Chemical 2]

The concentration range of PQQ trimethyl ester in this reaction is not particularly limited and is usually 0.0001.
A concentration range of 10 mM is preferred. As the acid to be used, an organic acid such as trifluoroacetic acid, trichloroacetic acid, trifluoromethylsulfonic acid, methylsulfonic acid or a mineral acid can be used, and trifluoroacetic acid is particularly effective. The amount of water used at the same time is 0.0 with respect to the acid.
It is used in a volume range of 1 to 10 times, and for example, when trifluoroacetic acid is used, about 0.5 times volume is effective. The reaction temperature and reaction time are important in this reaction, usually the reaction temperature is in the range of 10 to 100 ° C., and the reaction time is 1 to
It is carried out in 24 hours, and it is necessary to appropriately select a reaction time suitable for the reaction temperature.

The compound 1 obtained in the present reaction can be separated and purified from the reaction mixture by, for example, appropriately adopting operations such as concentration, extraction, column chromatography and recrystallization. Compound 2 is prepared by first converting PQQ trimethyl ester (Compound A) into a monomethyl ester (Compound B) by a partial hydrolysis reaction under basic conditions as shown in Chemical Formula 3 below, and then converting it to Chemical Formula 4 As described above, it can be produced by selectively methylating this monomethyl ester.

[0009]

[Chemical 3]

[0010]

[Chemical 4]

The conversion of compound A to compound B can be carried out by the method described in the literature (Oshiro et al., Chem. Exp., 1, 315, 1986). The method of separating and purifying the compound B obtained in this reaction from the reaction mixture can be carried out by appropriately adopting operations such as concentration, extraction, column chromatography and recrystallization. For example, after the reaction, the mixture is adjusted to pH 1 with hydrochloric acid, the aqueous layer is extracted with ethyl acetate, dried and concentrated, and the obtained solid is washed with ether to obtain a highly pure compound B.

In the reaction from compound B to compound 2,
The concentration range of Compound B is not particularly limited and is usually 0.0
A concentration range of 01-10 mM is preferred. A mineral acid such as sulfuric acid may be used as the acid. The amount of the methanol used at the same time is not particularly limited, but the compound B is used.
The range of 1 to 10 times the molar amount relative to the compound is preferable.
The reaction temperature is in the range of 10 to 100 ° C, and the reaction time is 1 to 2
It is carried out in 4 hours, and it is necessary to appropriately select a reaction time suitable for the reaction temperature. The method of separating and purifying Compound 2 obtained in this reaction from the reaction mixture can be carried out by appropriately adopting operations such as concentration, extraction, column chromatography, recrystallization and drying.

[0013]

EXAMPLES The present invention will be described more specifically by way of examples, but the present invention is not limited to these examples. Example 1 2,9-dimethoxycarbonyl-7-carboxy-4,
5-dihydro-4,5-dioxo-1H-pyrrolo [2,
Synthesis of 3-f] quinoline (Compound 1) PQQ trimethyl ester 100 mg (0.269 mm
was dissolved in 5 ml of a mixed solvent of trifluoroacetic acid-water (trifluoroacetic acid / water = 3/1), and this was heated at 60 ° C. for 12 hours. After cooling, 15 ml of water was added and extracted with chloroform. After drying with sodium sulfate,
The solvent was distilled off and the obtained orange solid was thoroughly washed with ether. After drying under reduced pressure, 64 mg (yield 67%) of the title compound was obtained as orange-red crystals.

The physical properties of this compound are as follows. Melting point 219 to 221 ° C infrared absorption spectrum (KBr method); νmax = 3236, 175
2, 1718, 1690cm ^-1 Hydrogen nuclear magnetic resonance spectrum (heavy dimethyl sulfoxide,
Tetramethylsilane internal standard); δ = 3.89 (s, 3H), 4.
05 (s, 3H), 7.28 (s, 1H), 8.56 (s, 1H), 12.52 (s, 1H) pp
m. Carbon nuclear magnetic resonance spectrum (heavy dimethyl sulfoxide,
Tetramethylsilane internal standard); δ = 52.3, 54.2, 11
3.9, 124.8, 126.3, 126.4, 128.5, 133.7, 134.1, 14
7.0, 148.9, 159.8, 164.7, 166.7, 173.3, 177.3ppm UV-visible absorption spectrum; λmax = 258 (ε = 23,700),
357 (12,900) nm. Mass spectrum (EImass); m / e = 360 (M ⁺ +2, 20
%), 358 (M ⁺ , 35%), 254 (100%).

Example 2 2,7-Dimethoxycarbonyl-9-carboxy-4,
5-dihydro-4,5-dioxo-1H-pyrrolo [2,
Synthesis of 3-f] quinoline (Compound 2) It was synthesized from PQQ trimethyl ester in two steps as follows. 1) 2-methoxycarbonyl-7,9-dicarboxy-
4,5-dihydro-4,5-dioxo-1H-pyrrolo
Synthesis of [2,3-f] quinoline (Compound B) PQQ trimethyl ester 150 mg (0.403 mm
ol) with 75 ml of acetonitrile and 75 ml of 0.1
Dissolve in a mixed solvent of M potassium carbonate aqueous solution and add 2
The mixture was stirred at 5 ° C for 4 hours. PH of the reaction mixture with concentrated hydrochloric acid
It was adjusted to 1 and extracted with ethyl acetate. After drying over sodium sulfate, the solvent was distilled off and the obtained orange solid was thoroughly washed with ether. After drying under reduced pressure, 98 mg (yield 64
%) Of the title compound as red crystals. The physical properties of this compound were as follows. Melting point> 300 ° C (decomposition) Infrared absorption spectrum (KBr method); νmax = 3288, 171
6, 1654cm ^-1 Hydrogen nuclear magnetic resonance spectrum (deuterated dimethyl sulfoxide,
Tetramethylsilane internal standard); δ = 3.88 (s, 3H), 7.
27 (s, 1H), 8.61 (s, 1H), 13.49 (s, 1H) ppm. Carbon nuclear magnetic resonance spectrum (deuterium dimethyl sulfoxide,
Tetramethylsilane internal standard); δ = 52.3, 113.8, 1
24.5, 125.9, 126.2, 129.1, 134.4, 136.1, 147.0, 14
8.8, 159.8, 164.9, 166.7, 173.3, 177.7ppm Mass spectrum (FAB mass); positive 347 (M ⁺
+ 2 + 1, 5%), negative 345 (M ⁺ + 2-1, 6%).

2) 2,7-dimethoxycarbonyl-9-
Carboxy-4,5-dihydro-4,5-dioxo-1
Synthesis of H-pyrrolo [2,3-f] quinoline (Compound 2) 85 mg (0.247 mol) of Compound B was dissolved in 15 ml of methanol, and 0.3 ml of concentrated sulfuric acid was added dropwise to the mixture, and the mixture was mixed with 60 Heat at 4 ° C. for 4 hours. After completion of the reaction, the pH was adjusted to 5 with 0.1M potassium carbonate, and the mixture was extracted with ethyl acetate. After drying over sodium sulfate, the solvent was distilled off and the obtained red solid was purified by silica gel chromatography (developing solvent, ethyl acetate / acetic acid = 1/2) and then recrystallized from ethyl acetate to give 36 mg (yield). rate
41%) of the title compound was obtained as red crystals. The physical properties of this compound were as follows. Melting point 243-244 ° C infrared absorption spectrum (KBr method); νmax = 3460, 170
8, 1654cm ^-1 Hydrogen nuclear magnetic resonance spectrum (deuterated dimethyl sulfoxide,
Tetramethylsilane internal standard); δ = 3.87 (s, 3H),
3.95 (s, 3H), 7.27 (s, 1H), 8.63 (s, 1H), 14.52 (s, 1H)
ppm. Mass spectrum (FAB mass); positive 361 (M ⁺ + 2 + 1, 10%), 360 (M ⁺ +2, 11%). negative 359 (M ⁺ + 2-1, 23%). UV-visible Absorption spectrum; λ max = 258 (ε = 23,500),
354 (12,600) nm.

[0017]

INDUSTRIAL APPLICABILITY The novel compound of the present invention is a novel pyrroloquinoline quinone and its salt, and is expected to be used as a new physiologically active substance as a medicine or an agricultural chemical.

Claims (1)

[Claims] 1. A novel pyrroloquinoline quinone derivative represented by Chemical formula 1 and a salt thereof. [Chemical 1] [However, in Chemical formula 1, R ₁ and R ₂ represent a hydrogen atom or a methyl group. However, the case where both are a hydrogen atom or a methyl group is excluded. ]