JPH11255711A - Naphthylpropenoic acid derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound free from harmful action such as toxicity or irritation, excellent in ultraviolet light absorbing property, stability and persistency of effect, especially solubility to nonpolar oil bases, and having extremely high ultraviolet light protecting effect when used for skin, hair, or the like. SOLUTION: This compound is represented by the formula NAP-CH=CHCO2 R<1> (NAP is naphthyl; R<1> is a 6-12C straight-chain or branched chain alkyl), e.g. 2-ethylhexyl 6-methoxy-2-naphthylpropenoate. The compound is obtained by condensing, e.g. a naphthoaldehyde derivative of the formula NAP-CHO with an acetate derivative of the formula CH3 COR<1> in the presence of an alkali such as pyridine. The reaction is preferably carried out under heating. Furthermore, when the compound is used as ultraviolet light absorbent for skin or hair, the compound is preferably carried on a support. The compound is preferably formulated at a ratio of 0.5-10 wt.% in the case of skin preparation for external use, 0.001-5 wt.% in the case of shampoo, or the like and 0.1-20 wt.% in the case of rinse, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention has an excellent ultraviolet absorbing effect, has excellent solubility in non-polar bases, has an excellent ultraviolet protection effect when applied to the skin, and is easy to manufacture. The present invention relates to a naphthylpropenoic acid derivative, an ultraviolet absorbent, a skin external preparation and a hair cosmetic containing such a naphthylpropenoic acid derivative.

[0002]

2. Description of the Related Art As the effects of ultraviolet rays on human skin and hair become evident, compounds that absorb UV-A and UV-B (ultraviolet absorbers) in order to prevent this have been clarified. Is being developed. For example, as a UV-A absorber, those containing derivatives such as benzophenone and benzoylmethane are known,
UV-B absorbers include cinnamic acid, benzophenone,
Those containing derivatives such as 4-aminobenzoic acid and salicylic acid are known.

However, these are all (a) U
Absorb VA and UV-B as much as possible; (b)
It is stable against light and heat, (c) has no toxicity, irritation, and other harmful effects to the skin, (d) maintains its effect, and (e) has excellent solubility in cosmetic bases. It does not satisfy all of the properties required as a UV absorber for protecting the skin and hair, such as the fact that it is protected. In particular, it is known that conventional ultraviolet absorbers have insufficient stability to light (ultraviolet light) among these properties, and decomposition and reaction by ultraviolet light occur [for example,
Int. J. Cosmetic Science, 1
0, 53 (1988)]. Such decomposition of the UV absorber not only causes a reduction in the duration of the effect, but also does not disregard the effect on the skin of the decomposed product itself or the product of the reaction between the decomposed product and the compound [Fragrance Journal, 84, 32 (1987)].

[0004] In addition, since skin external preparations and hair cosmetics containing an ultraviolet absorber are frequently used in hot summers, there is an increasing need for prevention of runoff due to sweat or a water bath and enhancement of sustainability. ing. Therefore, in recent years, as a base for skin external preparations and hair cosmetics, excellent water resistance,
In addition, various non-polar oil bases such as silicone oil and squalane which are excellent in usability have been widely used. However, most conventional UV absorbers are
There is a problem that the solubility in these non-polar oil bases is extremely low and it is difficult to use them in combination.

Accordingly, the present invention has excellent solubility in non-polar oil bases such as silicone oil and squalane, which have been inadequate in the past, particularly in the above-mentioned conditions (a) to (e) required for an ultraviolet absorber, It is an object of the present invention to provide a substance having an extremely high ultraviolet ray protective effect when actually used on the skin and the hair, and an ultraviolet absorbent for skin or hair, an external preparation for the skin and a hair cosmetic containing such a substance. .

[0006]

Means for Solving the Problems The present inventors have found that a naphthylpropenoic acid derivative represented by the following general formula (2) meets this purpose. Furthermore, they have found that a naphthylpropenoic acid derivative represented by the following general formula (1) is a novel substance, and have completed the present invention.

That is, the present invention provides the following general formula (1)

[0008]

NAP-CH = CHCO ₂ R ¹ (1)

(Wherein NAP represents a naphthyl group which may have a substituent, and R ¹ represents a linear or branched alkyl group having 6 to 12 carbon atoms). An acid derivative is provided. The present invention also provides the following general formula (2)

[0010]

Embedded image NAP-CH = CHCO ₂ R ² (2)

Wherein NAP represents a naphthyl group which may have a substituent, and R ² represents a linear or branched alkyl group having 1 to 12 carbon atoms. An ultraviolet absorber containing an acid derivative is provided. The present invention also provides a skin external preparation containing a naphthylpropenoic acid derivative represented by the general formula (2). The present invention also provides a hair cosmetic containing a naphthylpropenoic acid derivative represented by the general formula (2).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formula (1), -CH = CHCO
Naphthyl group represented by the _{NAP 2} R ¹ is attached, a 1-naphthyl group may be either a 2-naphthyl group. Further, they may have the same or different one or more substituents. Such substituent may be bonded to any carbon atom other than a carbon atom -CH = CHCO ₂ R ¹ is attached. These substituents are not particularly limited, and examples thereof include a linear or branched alkyl group having 1 to 5 carbon atoms, a hydroxyl group, and a linear or branched alkoxyl group having 1 to 5 carbon atoms. An alkoxyl group is preferable, and a methoxy group is particularly preferable, in view of the magnitude of the ultraviolet absorbing action and the availability of raw materials.

In the general formula (1), R ¹ has 6 to 6 carbon atoms.
It represents 12 linear or branched alkyl groups. Among these, an alkyl group having 6 to 12 carbon atoms is preferable from the viewpoint of solubility in a nonpolar oil base and high UV protection effect when used for skin or hair, and 2-ethylhexyl group and 3,
The 5,5-trimethylhexyl group is particularly preferred.

The naphthylpropenoic acid derivative has cis and trans isomers. In the present invention, either one of the isomers or a mixture of any ratio may be used.

The method for producing the naphthylpropenoic acid derivative represented by the general formula (1) of the present invention is not particularly limited, but can be produced, for example, by the following method.

[0016]

Embedded image

Wherein NAP and R ¹ are the same as above. That is, it can be obtained by condensing a naphthaldehyde derivative (3) and an acetate derivative (4) with an alkali without a solvent or in a solvent.

The solvent used in this reaction is not particularly limited as long as it does not inhibit the reaction, and hexane, cyclohexane, benzene, toluene, xylene, tetrahydrofuran, 1,4-dioxane, alcohols and the like can be mentioned. . As the alkali, piperidine,
Examples thereof include amines such as pyridine, sodium hydride, sodium alkoxide, sodium hydroxide, and the like, and these can be used in appropriate combination. This reaction is preferably performed while heating.

The naphthylpropenoic acid derivative of the present invention can be obtained by subjecting a naphthylpropenoic acid derivative having a different ester chain length to a transesterification reaction using an alkali or acid catalyst.

The ultraviolet absorbent for skin or hair of the present invention comprises:
It contains a naphthylpropenoic acid derivative represented by the general formula (2). By blending such Nafuchirupuropen acid derivative, it shows the ultraviolet radiation protection effect for skin or hair ultraviolet absorber excellent, of which R ² is wherein the carbon number of Nafuchirupuropen acid derivative having from 6 to 12 However, the solubility in a non-polar oil base is particularly excellent, and thus it is preferable.

The ultraviolet absorbent for skin or hair of the present invention comprises:
Although the naphthylpropenoic acid derivative represented by the general formula (2) may be used as it is, it is preferable that the naphthylpropenoic acid derivative is supported on a suitable carrier. The carrier used here is not particularly limited as long as it is inactive with respect to the naphthylpropenoic acid derivative represented by the general formula (2), and may be in any form such as a solid, a liquid, a milk, and a gel. . The naphthylpropenoic acid derivative represented by the general formula (2) may be used alone or in combination of two or more.

Further, the ultraviolet absorbent for skin or hair of the present invention may optionally contain other ultraviolet absorbents. Other examples of the ultraviolet absorber include 4-methoxycinnamic acid ester. Further, if necessary, for example, an antioxidant, a preservative, a fragrance, a coloring agent, a surfactant and the like can be added. The ultraviolet absorbent for skin or hair of the present invention can be produced by mixing a naphthylpropenoic acid derivative represented by the general formula (2) and other components according to a conventional method.

The external preparation for skin and the cosmetic for hair of the present invention comprise one or more of naphthylpropenoic acid derivatives represented by the general formula (2), and a base generally used for an external preparation for skin or a hair cosmetic. And other components.

External preparations for skin are roughly classified into external preparations for medical use and skin cosmetics. Examples of the medicated skin external preparation include oily bases, oil-in-water or water-in-oil emulsifying bases, water-soluble bases, ointments based on suspending bases, lotions and aerosols. And various medicinal ingredients are compounded.
Examples of skin cosmetics include oil-in-water or water-in-oil type emulsified cosmetics, creams, emulsions, lotions, oily cosmetics, lipsticks, foundations, skin cleansers, and the like.

Examples of hair cosmetics include dosage forms such as aqueous solutions, ethanol solutions, emulsions, suspensions, gels, solids, aerosols, and powders. Shampoos, rinses, treatments, conditioners, hair liquids, hair tonics, hair restorers, Examples include a hair restorer and a hair spray.

Further, the external preparation for skin and the cosmetic for hair of the present invention may contain, in accordance with their respective purposes, an ultraviolet absorber other than the naphthylpropenoic acid derivative represented by the general formula (2), a medicinal component, a surfactant, W / O or O / W type emulsifier, emulsifier for silicone oil agent, emulsion stabilizer, chelating agent, thickener, whitening agent, pH adjuster, antioxidant, preservative, humectant,
Dyes, fragrances and the like can be appropriately blended.

The content of the naphthylpropenoic acid derivative represented by the general formula (2) in the external preparation for skin and the hair cosmetic of the present invention is not particularly limited. Although it can be appropriately determined depending on the degree, in general, 0.1 to 2 for a skin external preparation.
0% by weight, particularly preferably 0.5 to 10% by weight, 0.001 to 5% by weight for hair cosmetics in shampoos and the like, and 0.1 to 20% by weight in rinses, treatments, conditioners and the like , Hair liquid, hair tonic, etc., is preferably 0.01 to 10% by weight. The skin external preparation and the hair cosmetic of the present invention can be synthesized according to a conventional method by mixing a naphthylpropenoic acid derivative represented by the general formula (2) and other components.

[0028]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Example 1 Synthesis of 2-ethylhexyl 6-methoxy-2-naphthylpropenoate (1-1)

[0030]

Embedded image

300 ml with magnetic stirrer and reflux condenser
1.15 g of sodium hydride (50
mmol), 6-methoxy-2-naphthaldehyde (1-
3) 5.59 g (30 mmol) and 10.34 g (60 mmol) of 2-ethylhexyl acetate (1-4) in 20 ml of THF
Added. This was heated and stirred at 70 ° C. for 3 hours. After cooling, 50 ml of a 1N aqueous hydrochloric acid solution was added, extracted with 50 ml of ethyl acetate, and washed once with water. After the organic layer was dried over anhydrous magnesium sulfate, the solvent was distilled off to obtain a yellow oil. This oily product was purified by silica gel column chromatography using hexane-ethyl acetate (50: 1) as a developing solvent, and the target compound (1-1) as white crystals was obtained.
2.53 g (yield 25%) was obtained. The resulting compound (1
Physical properties of -1) are as follows.

Melting point 38 ° C. ¹ H-NMR (CDCl ₃ , δ) 0.81-1.11 (m, 6H), 1.21-
1.75 (m, 9H), 3.93 (s, 3H), 4.14 (d, 2H, J = 5.8Hz), 6.51 (d,
1H, J = 15.9Hz), 7.10-7.22 (m, 2H), 7.59-7.90 (m, 4H), 7.8
1 (d, 1H, J = 15.9Hz) IR (ν _KBr, cm ^-1 ) 2965, 1710, 1630, 1605, 1485, 146
5, 1395, 1265, 1170, 1030, 850 UV (EtOH, λ _max (ε)) 325 nm (24,900)

Example 2 Synthesis of 2-ethylhexyl 1-naphthylpropenoate (2-1)

[0034]

Embedded image

The reaction was carried out in the same manner as in Example 1 except that 1-naphthaldehyde was used instead of 6-methoxy-2-naphthaldehyde, and the target compound (2-
1) was obtained as a pale yellow oil (yield 42%). Physical properties of compound (2-1) obtained are as described below.

¹ H-NMR (CDCl ₃ , δ) 0.88-1.12
(m, 6H), 1.25-1.78 (m, 9H), 4.18 (d, 2H, J = 5.8Hz), 6.54
(d, 1H, J = 15.8Hz), 7.45-7.62 (m, 3H), 7.76-7.92 (m, 3H),
8.17-8.21 (m, 1H), 8.53 (d, 1H, J = 15.8Hz) IR (ν _neat, cm ^-1 ) 2965, 2935, 2870, 1715, 1635, 1
465, 1305, 1240, 1170, 980, 775 UV (EtOH, λ _max (ε)) 324 nm (12,000)

Test Example 1 Ultraviolet absorbing action Compounds (1-1) and (2-1) obtained in Examples 1 and 2
And 2-hydroxy-4-methoxybenzophenone (comparative product 1) and 2-ethylhexyl 4-methoxycinnamate (comparative product 2), which are currently widely used UV absorbers for skin or hair The ultraviolet absorption effect (absorbance) was measured by the following method. Table 1 shows the results
Shown in

(Measurement method) Each UV absorber was dissolved in ethanol (99.5% special reagent), and 2.5 × 10 ⁻⁵ mo
A solution having a l / l concentration was prepared, and this was placed in a quartz cell (1 × 1c).
m), a self-recording spectrophotometer (U-341 manufactured by Hitachi, Ltd.)
(0 type).

[0039]

[Table 1]

As is evident from Table 1, the ultraviolet absorbent of the present invention exhibited an equal or higher absorption effect even when compared with Comparative Examples 1 and 2. This tendency was remarkable in the compound (1-1) when the wavelength was 320 nm or more.

Test Example 2 Solubility test Compounds (1-1) and (2-1) obtained in Examples 1 and 2
Was dissolved in a non-polar oil base using an ultraviolet absorber composed of butyl-methoxydibenzoylmethane (Comparative Product 3). Table 2 shows the results.

(Evaluation method) When 3% and 10% by weight of each ultraviolet absorber is added to octamethylcyclotetrasiloxane (silicone oil) which is a non-polar oil base, and 5% and 10% by weight are added to squalane. Was observed for its solubility.

[0043]

[Table 2]

As is clear from Table 2, the ultraviolet absorber of the present invention had higher solubility in any non-polar oil base than the comparative product. In addition, the ultraviolet absorber of the present invention also showed good solubility in ethanol.

Formulation Examples 1 and 2 An external preparation for skin (W / O type cream) having the following composition was obtained by a conventional method.

[0046]

[Table 3]

Further, a W / O type cream was produced with the same composition except that the compound (2-1) was used instead of the compound (1-1).

Formulation Examples 3 and 4 A skin external preparation (foundation) having the following composition was prepared by a conventional method.

[0049]

[Table 4]

Further, a foundation was produced with the same composition except that the compound (1-1) was used instead of the compound (2-1).

Formulation Examples 5 and 6 A hair conditioner having the following composition was produced by a conventional method.

[0052]

[Table 5]

Further, a hair conditioner was produced with the same composition except that the compound (2-1) was used instead of the compound (1-1).

[0054]

The naphthylpropenoic acid derivative represented by the general formula (1) has an excellent ultraviolet absorbing effect, and has excellent solubility in non-polar oil bases and other bases. It is excellent in compoundability and formulation stability in preparations and hair cosmetics, and exhibits an extremely high ultraviolet protection effect when actually used on skin or hair and has high safety to skin and hair. Further, the naphthylpropenoic acid derivative represented by the general formula (2) has an excellent ultraviolet absorbing effect, has excellent solubility in a non-polar oil base and other bases, and contains an ultraviolet absorber containing the same. In addition, the external preparation for skin and the hair cosmetic can exhibit an excellent ultraviolet protection effect with a long duration and an excellent feeling upon use.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI A61K 31/215 ADA A61K 31/215 ADA C09K 3/00 104 C09K 3/00 104Z (72) Inventor Yoshiaki Fujikura Shellfish in Haga-gun, Tochigi Prefecture 2606 Akabane-cho Kao Corporation Research Laboratory

Claims (4)

[Claims] 1. The following general formula (1): NAP-CH = CHCO ₂ R ¹ (1) (wherein, NAP represents a naphthyl group which may have a substituent, and R ¹ is A naphthylpropenoic acid derivative represented by a linear or branched alkyl group having 6 to 12 carbon atoms). 2. The following general formula (2): NAP-CH = CHCO ₂ R ² (2) (wherein NAP represents a naphthyl group which may have a substituent, and R ² represents A linear or branched alkyl group having 1 to 12 carbon atoms), which contains a naphthylpropenoic acid derivative. 3. The following general formula (2): NAP-CH = CHCO ₂ R ² (2) (wherein NAP represents a naphthyl group which may have a substituent, and R ² represents An external preparation for skin containing a naphthylpropenoic acid derivative represented by the formula: which represents a linear or branched alkyl group having 1 to 12 carbon atoms. 4. The following general formula (2): NAP-CH = CHCO ₂ R ² (2) (wherein NAP represents a naphthyl group which may have a substituent, and R ² represents And a linear or branched alkyl group having 1 to 12 carbon atoms).