5-deazaflavin compound-containing emulsion and method for producing same

Abstract

The problem addressed by the present invention is to provide a 5-deazaflavin compound-containing emulsion and a method for producing the same. As a solution, a 5-deazaflavin compound-containing emulsion according to the present invention contains at least (1) a 5-deazaflavin compound, (2) benzyl alcohol and / or phenoxyethanol, (3) polysorbate and lecithin, (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid, (5) a fat / oil, and (6) an aqueous medium as constituent components.

Description

5-deazaflavin compound-containing emulsion and method for producing same

[0001] The present invention relates to an emulsion containing a 5-deazaflavin compound and a method for producing the same.

[0002] In recent years, attention has been focused on methods for preventing and treating diseases caused by a functional decline in intracellular energy production, such as Alzheimer's disease, Parkinson's disease, neurodegenerative diseases associated with cerebral hemorrhage or cerebral infarction, and depression, as well as for anti-aging care, by improving the functional decline in intracellular energy production. Therefore, active ingredients for improving the functional decline in intracellular energy production have been actively searched for, and a 5-deazaflavin compound has been reported as one such active ingredient in Patent Document 1.

[0003] The 5-deazaflavin compound reported in Patent Document 1 has an excellent activating effect on the production of adenosine triphosphate (ATP) in cells, and is therefore highly anticipated as an active ingredient for improving the functional decline of energy production in cells. However, since the 5-deazaflavin compound is a condensed polycyclic aromatic heterocyclic compound, it is poorly soluble in both water and oil (oils and fats), making it difficult to formulate into a liquid formulation.

[0004] Patent No. 6717989

[0005] Therefore, an object of the present invention is to provide an emulsion containing a 5-deazaflavin compound and a method for producing the same.

[0006] As a result of intensive investigations conducted by the present inventors in light of the above points, they found that an emulsion containing a 5-deazaflavin compound can be produced by dissolving a 5-deazaflavin compound in benzyl alcohol or phenoxyethanol and emulsifying the compound by appropriately selecting constituent components.

[0007] The 5-deazaflavin compound-containing emulsion of the present invention, developed based on the above findings, comprises at least the following constituent components as set forth in claim 1: (1) a 5-deazaflavin compound, (2) benzyl alcohol and / or phenoxyethanol, (3) polysorbate and lecithin, (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid, (5) an oil or fat, and (6) an aqueous medium. The 5-deazaflavin compound-containing emulsion of claim 2 comprises the 5-deazaflavin compound-containing emulsion of claim 1, further comprising (7) an aromatic carboxylic acid as a constituent component. The 5-deazaflavin compound-containing emulsion of claim 3 comprises the 5-deazaflavin compound-containing emulsion of claim 1, wherein the 5-deazaflavin compound is a compound represented by the following general formula (I):

[0008]

[0009] [In the formula, R １ represents a hydrogen atom, a lower alkyl group, or an optionally substituted phenyl group. ２ represents a lower alkyl group, a lower cycloalkyl group, or an optionally substituted phenyl group. ３ and R ４ are the same or different and represent any one of a hydrogen atom, a halogen atom, a hydroxy group, a nitro group, a cyano group, a lower alkyl group, a lower alkoxy group, a lower alkylamino group, and a lower alkylsulfonyl group.] Furthermore, the method for producing a 5-deazaflavin compound-containing emulsion of the present invention, as described in claim 4, comprises emulsifying components comprising at least: (1) a 5-deazaflavin compound, (2) benzyl alcohol and / or phenoxyethanol, (3) polysorbate and lecithin, (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid, (5) an oil or fat, and (6) an aqueous medium.

[0010] According to the present invention, it is possible to provide an emulsion containing a 5-deazaflavin compound and a method for producing the same.

[0011] The 5-deazaflavin compound-containing emulsion of the present invention comprises at least the following components: (1) a 5-deazaflavin compound; (2) benzyl alcohol and / or phenoxyethanol; (3) polysorbate and lecithin; (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid; (5) an oil or fat; and (6) an aqueous medium.

[0012] In the present invention, a 5-deazaflavin compound means a compound having a 5-deazaflavin skeleton (a skeleton in which the nitrogen atom at the 5-position of the flavin skeleton is replaced with a carbon atom), and specific examples thereof include the compound represented by the following general formula (I) described in Patent Document 1:

[0013]

[0014] [In the formula, R １ represents a hydrogen atom, a lower alkyl group, or an optionally substituted phenyl group. ２ represents a lower alkyl group, a lower cycloalkyl group, or an optionally substituted phenyl group. ３ and R ４ are the same or different and represent any one of a hydrogen atom, a halogen atom, a hydroxy group, a nitro group, a cyano group, a lower alkyl group, a lower alkoxy group, a lower alkylamino group, and a lower alkylsulfonyl group.

[0015] Here, the term "lower alkyl group" refers to a straight-chain or branched-chain alkyl group having 1 to 6 carbon atoms, and specific examples thereof include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and tert-butyl groups. The term "lower cycloalkyl group" refers to a cycloalkyl group having 3 to 7 carbon atoms, and specific examples thereof include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. The term "lower alkoxy group" refers to a straight-chain or branched-chain alkoxy group having 1 to 6 carbon atoms, and specific examples thereof include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, and tert-butoxy groups. The term "lower alkylamino group" refers to an alkylamino group whose lower alkyl moiety is as defined above, and specific examples thereof include methylamino, ethylamino, and propylamino groups. The term "lower alkylsulfonyl group" refers to an alkylsulfonyl group whose lower alkyl moiety is as defined above, and specific examples include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, etc. Examples of substituents that the optionally substituted phenyl group may have include a halogen atom, a hydroxy group, a nitro group, a cyano group, a carboxyl group, an amino group, a lower alkyl group, a lower alkoxy group, a lower alkylamino group, etc. The lower alkyl group, the lower alkoxy group, and the lower alkylamino group have the same meanings as defined above.

[0016] The reason why benzyl alcohol and / or phenoxyethanol are used in the present invention is that these are liquids that are poorly soluble in aqueous media and can dissolve a 5-deazaflavin compound, and therefore these dissolved 5-deazaflavin compounds are present in the emulsion as droplets of the dissolved 5-deazaflavin compound (corresponding to fat particles in which a drug is dissolved in a drug-containing fat emulsion).

[0017] In the present invention, polysorbate (polyoxyethylene sorbitan fatty acid ester) and lecithin serve as emulsifiers for dispersing droplets of the 5-deazaflavin compound dissolved in benzyl alcohol and / or phenoxyethanol in the emulsion. It is essential to use a mixture of polysorbate and lecithin. Using either of these alone would prevent the production of a stable 5-deazaflavin compound-containing emulsion (the emulsion would separate into two phases immediately after production, or precipitates or sediments would form in the emulsion). Examples of polysorbates that can be used include polysorbate 20, 40, 60, 65, and 80 (these may be used alone or in a mixture of two or more). Examples of lecithins that can be used include egg yolk lecithin, soybean lecithin, hydrogenated egg yolk lecithin, and hydrogenated soybean lecithin (these may be used alone or in a mixture of two or more).

[0018] In the present invention, specific examples of pharmaceutically acceptable salts of aromatic carboxylic acids include pharmaceutically acceptable salts of benzoic acid, salicylic acid, phthalic acid, isophthalic acid, and terephthalic acid, for example, alkali metal salts such as sodium salts and potassium salts, and alkaline earth metal salts such as magnesium salts and calcium salts (these may be used alone or in combination of two or more).

[0019] In the present invention, specific examples of fats and oils include vegetable oils such as soybean oil, corn oil, coconut oil, safflower oil, perilla oil, olive oil, castor oil, and cottonseed oil, as well as known fats and oils that can be used as fats and oils, such as animal oils such as lanolin, egg yolk oil, fish oil, mineral oils such as liquid paraffin, medium-chain fatty acid triglycerides, chemically synthesized triglycerides, and gelled hydrocarbons (these may be used alone or in combination of two or more).

[0020] In the present invention, specific examples of aqueous media include water (pure water, purified water, water for injection, etc.), as well as acetic acid-sodium acetate, boric acid-sodium carbonate, boric acid-sodium tetraborate, hydrochloric acid-sodium tetraborate, phosphoric acid-sodium phosphate, sodium dihydrogen phosphate-disodium hydrogen phosphate, citric acid-sodium hydroxide, hydrochloric acid-potassium hydrogen phthalate, sodium hydroxide-potassium hydrogen phthalate, citric acid-disodium hydrogen phosphate, succinic acid-sodium tetraborate, ammonia-ammonium chloride, potassium dihydrogen phosphate-disodium hydrogen phosphate-phosphoric acid, and potassium dihydrogen phosphate-phosphoric acid water. Examples of such buffer solutions include those prepared by adding trisodium citrate-sodium hydroxide, potassium dihydrogen phosphate-disodium hydrogen phosphate, potassium dihydrogen phosphate-sodium hydroxide, disodium hydrogen phosphate-sodium hydroxide, Tris (abbreviation for trishydroxymethylaminomethane, the same applies hereinafter)-hydrochloric acid, Tris-EDTA, Tris-acetate-EDTA, trisodium citrate-sodium hydroxide-sodium chloride, sodium dihydrogen phosphate-EDTA-sodium chloride, or the like to water, to adjust the pH to a predetermined range, for example, 3.5 to 9.0, preferably 5.0 to 8.5, and more preferably 6.5 to 8.0.

[0021] The 5-deazaflavin compound-containing emulsion of the present invention may further contain an aromatic carboxylic acid. By further containing an aromatic carboxylic acid, the dissolving power of the 5-deazaflavin compound in benzyl alcohol and / or phenoxyethanol can be increased. Specific examples of aromatic carboxylic acids include benzoic acid, salicylic acid, phthalic acid, isophthalic acid, and terephthalic acid (these may be used alone or in combination of two or more).

[0022] The content of the 5-deazaflavin compound in the 5-deazaflavin compound-containing emulsion of the present invention may be, for example, 0.01 to 30 mg / g (the upper limit is preferably 20 mg / g, more preferably 10 mg / g). The content of benzyl alcohol and / or phenoxyethanol is preferably at least 5 times the content of the 5-deazaflavin compound, more preferably at least 10 times. If the content is less than 5 times, even if an aromatic carboxylic acid is further added to increase the dissolving power of the 5-deazaflavin compound in the emulsion, it may be impossible to dissolve the entire amount of the 5-deazaflavin compound. However, the upper limit is preferably 250 mg / g, more preferably 150 mg / g, and even more preferably 100 mg / g. The total content of polysorbate and lecithin is preferably 0.5 to 5 times the content of benzyl alcohol and / or phenoxyethanol. If the content is less than 0.5 times, emulsification may be difficult. However, the upper limit is preferably 200 mg / g, more preferably 150 mg / g. The proportion of polysorbate in the total content of polysorbate and lecithin is, for example, 5 to 96%. As the proportion of polysorbate in the total content of polysorbate and lecithin increases, the viscosity of the 5-deazaflavin compound-containing emulsion produced decreases. The content of the pharmaceutically acceptable salt of aromatic carboxylic acid is preferably 0.5 to 5 times the content of benzyl alcohol and / or phenoxyethanol. However, the upper limit is preferably 200 mg / g, more preferably 150 mg / g, and even more preferably 100 mg / g. The content of oils and fats is preferably 0.01 to 1 times the content of benzyl alcohol and / or phenoxyethanol. Because oils and fats are miscible with benzyl alcohol and / or phenoxyethanol, a high content of oils and fats may hinder the dissolution of the 5-deazaflavin compound by benzyl alcohol and / or phenoxyethanol. When an aromatic carboxylic acid is further contained, the upper limit of its content is preferably 0.5 times the content of benzyl alcohol and / or phenoxyethanol.

[0023] The method for producing the 5-deazaflavin compound-containing emulsion of the present invention is not particularly limited, and examples include a method in which the contents of the 5-deazaflavin compound, benzyl alcohol and / or phenoxyethanol, polysorbate and lecithin, pharmaceutically acceptable salt of aromatic carboxylic acid, oil and fat, and aromatic carboxylic acid (if further included) are set within the above-mentioned numerical ranges, and the 5-deazaflavin compound, oil and fat, and aromatic carboxylic acid (if further included) are dissolved in benzyl alcohol and / or phenoxyethanol to prepare an oil phase component, and the polysorbate, lecithin, and pharmaceutically acceptable salt of aromatic carboxylic acid are dissolved in an aqueous medium to prepare an aqueous phase component, and then the mixture is mixed and emulsified. The mixture of the oil phase component and the aqueous phase component can be emulsified by manual shaking or using a device such as a stirrer (mixer), ultrasonic emulsifier, or ultrasonic cleaner. The emulsification time may be, for example, 1 to 30 minutes. The droplets of benzyl alcohol and / or phenoxyethanol having a 5-deazaflavin compound dissolved therein (when an aromatic carboxylic acid is further contained, the aromatic carboxylic acid is also contained in the droplets) preferably have an average particle size of 300 nm or less, more preferably 200 nm or less, and even more preferably 100 nm or less. The lower limit is, for example, 1 nm (this can be adjusted, for example, by adjusting the emulsification conditions).

[0024] The 5-deazaflavin compound-containing emulsion of the present invention can be easily sterilized by filtration by reducing the average droplet size of the droplets to, for example, 200 nm or less, and can also be subjected to autoclaving. Autoclaving can be carried out by filling the 5-deazaflavin compound-containing emulsion of the present invention into a glass ampoule, a synthetic resin container, or the like, and then performing the autoclaving under general conditions (e.g., 120 to 122°C x 10 to 15 minutes).

[0025] The 5-deazaflavin compound-containing emulsion of the present invention may have its pH adjusted (for example, 3.5 to 9.0) or its osmotic pressure adjusted by adding a known pH adjuster or osmotic pressure adjuster. Furthermore, the 5-deazaflavin compound-containing emulsion of the present invention may also contain known preservatives, antioxidants, stabilizers, etc., as needed.

[0026] The 5-deazaflavin compound-containing emulsion of the present invention has excellent stability and can be stored at room temperature (e.g., 5 to 30°C). Furthermore, the 5-deazaflavin compound-containing emulsion of the present invention has transparency (turbidity of 0.5 or less), which facilitates visual confirmation of deterioration, foreign matter contamination, and formulation changes, and also provides a sense of security to patients receiving the emulsion. These effects are particularly effective when the 5-deazaflavin compound-containing emulsion of the present invention is used as a liquid preparation such as an injection, oral preparation, lotion, eye drop, nasal drop, ear drop, or inhalant (which may be diluted with an aqueous medium before use, if necessary).

[0027] The present invention will be described in detail below with reference to examples, but the present invention should not be construed as being limited to the following description.

[0028] Examples and Comparative Examples: The contents of test tubes containing predetermined amounts of four components (1) a 5-deazaflavin compound, (2) benzyl alcohol or phenoxyethanol, (5) an oil or fat, and (7) an aromatic carboxylic acid were dissolved in a 50°C water-filled ultrasonic cleaner (ASU-30) manufactured by AS ONE Corporation (operating time: 15 minutes) until homogeneous (oil phase component). The contents of test tubes containing predetermined amounts of three components (3) polysorbate and lecithin, (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid, and (6) an aqueous medium were dissolved in a 5-minute ultrasonic emulsifier (UH-50) manufactured by SMT Corporation (operating time: 5 minutes) until homogeneous (aqueous phase component). The aqueous phase component was added to the test tube containing the oil phase component, mixed, and emulsified for 5 minutes using an AS ONE Corporation test tube stirrer (HM-10) to produce a 5-deazaflavin compound-containing emulsion. The types and amounts of the seven components are shown in Table 1. In Table 1, (1) T-MAC used as the 5-deazaflavin compound is 10-ethyl-3-methylpyrimido[4,5-b]quinoline-2,4(3H,10H)-dione (in general formula (I), R １ = methyl group, R ２ = ethyl group, R ３ =R ４= hydrogen atom), and TN1160 is 8-chloro-3-methyl-10-phenylpyrimido[4,5-b]quinoline-2,4(3H,10H)-dione (in general formula (I), R １ = methyl group, R ２ = phenyl group, R ３ = hydrogen atom, R ４ = a compound containing a chlorine atom) (all of which are compounds described in Patent Document 1). (3) Polysorbates 20, 60, and 80 manufactured by NOF Corporation were used. Egg yolk lecithin used was PL-100M manufactured by Kewpie Corporation. (5) MCT (medium-chain triglyceride) was MCT oil manufactured by Nisshin Oillio Group. Soybean oil was manufactured by Croda. (6) The aqueous medium was pure water (1 mL = 1000 mg). "None" means that it was not used as a constituent component. "Polysorbate ratio" indicates the ratio of polysorbate content to the total content of polysorbate and lecithin.

[0029]

[0030] The average particle size of droplets contained in the 5-deazaflavin compound-containing emulsions immediately after production was measured using a particle size analyzer (Zetasizer Nano ZS) manufactured by Malvern Instruments using photon correlation spectroscopy. Furthermore, the test tubes containing the 5-deazaflavin compound-containing emulsions were capped and left to stand in a room for 12 hours, after which the properties of the emulsions were visually evaluated. The results are shown in Table 2. As is clear from Table 2, the 5-deazaflavin compound-containing emulsions produced in Examples 1 to 10, 14, and 19 to 23 had a polysorbate ratio (the proportion of polysorbate content in the total content of polysorbate and lecithin) of more than 60%, and therefore were emulsions with low viscosity. Therefore, it was possible to measure the average particle size of droplets contained in the emulsions, and the average particle size in all cases was 100 nm or less. The 5-deazaflavin compound-containing emulsions produced in Examples 11 to 13 and 15 to 18 had a polysorbate ratio of 60% or less, and therefore were highly viscous emulsions. Therefore, the average particle size of the droplets contained in the emulsions could not be measured using a particle size measurement device using a photon correlation method. However, the average particle size of the droplets could be measured by diluting the emulsions five times with pure water. The 5-deazaflavin compound-containing emulsions produced in all Examples were stable, transparent or pale yellow liquids that did not separate into two phases or produce precipitates or sediments even 12 hours after production, and no visible changes in properties were observed even after being left indoors for more than one month. The turbidity of the 5-deazaflavin compound-containing emulsions prepared in Examples 1 to 10, 14, and 19 to 23 was measured immediately after preparation using an ultraviolet spectrophotometer (UV1800) manufactured by Shimadzu Corporation, with the samples placed in measuring cells with a cell width of 1 cm and a wavelength of λ=620 nm (pure water used as the blank). Most of the emulsions had a turbidity of 0.1 or less, and even if they exceeded 0.1, they were 0.2 or less. The turbidity of the 5-deazaflavin compound-containing emulsions prepared in Examples 11 to 13 and 15 to 18 was often 0.3 to 0.4, and even if they exceeded 0.4, they were 0.5 or less (the turbidity decreased when diluted).

[0031] Furthermore, it was found that the inclusion of an aromatic carboxylic acid such as benzoic acid or salicylic acid as an additional constituent of the emulsion increases the solubility of the 5-deazaflavin compound in benzyl alcohol or the like, making it possible to dissolve the same amount of 5-deazaflavin compound in a smaller amount of benzyl alcohol or the like (comparison between Example 19 and Example 22, comparison between Example 21 and Example 23), or to dissolve a larger amount of 5-deazaflavin compound in the same amount of benzyl alcohol or the like (comparison between Example 2 and Example 19, comparison between Example 20 and Example 21).

[0032] The 5-deazaflavin compound-containing emulsions produced in all Comparative Examples underwent phase separation or the formation of precipitates or sediments immediately after production, and therefore the average particle size of the droplets contained in the emulsions was not measured. The poor stability of the 5-deazaflavin compound-containing emulsions produced in Comparative Examples was thought to be due to the fact that polysorbate and lecithin were not used as constituents (emulsifiers) of the emulsions, that pharmaceutically acceptable salts of aromatic carboxylic acids such as sodium salicylate and sodium benzoate were not used as constituents of the emulsions, and that fats and oils such as MCT and soybean oil were not used as constituents of the emulsions.

[0033]

[0034] Furthermore, emulsions containing the 5-deazaflavin compounds of the present invention were prepared using the types and amounts of constituent components shown in Table 3, and their stability and transparency were confirmed.

[0035]

[0036] The present invention has industrial applicability in that it can provide an emulsion containing a 5-deazaflavin compound and a method for producing the same.

Claims

1. A 5-deazaflavin compound-containing emulsion comprising at least the following components: (1) a 5-deazaflavin compound; (2) benzyl alcohol and / or phenoxyethanol; (3) polysorbate and lecithin; (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid; (5) an oil or fat; and (6) an aqueous medium.

2. The 5-deazaflavin compound-containing emulsion according to claim 1, further comprising (7) an aromatic carboxylic acid as a constituent.

3. The emulsion containing a 5-deazaflavin compound according to claim 1, wherein the 5-deazaflavin compound is a compound represented by the following general formula (I): [In the formula, R １ represents a hydrogen atom, a lower alkyl group, or an optionally substituted phenyl group. ２ represents a lower alkyl group, a lower cycloalkyl group, or an optionally substituted phenyl group. ３ and R ４ are the same or different and represent any one of a hydrogen atom, a halogen atom, a hydroxy group, a nitro group, a cyano group, a lower alkyl group, a lower alkoxy group, a lower alkylamino group, and a lower alkylsulfonyl group.

4. A method for producing an emulsion containing a 5-deazaflavin compound by emulsifying components comprising at least: (1) a 5-deazaflavin compound; (2) benzyl alcohol and / or phenoxyethanol; (3) polysorbate and lecithin; (4) a pharmaceutically acceptable salt of an aromatic carboxylic acid; (5) an oil or fat; and (6) an aqueous medium.

Images