CN110540544B - Preparation of alopecurone and application of alopecurone in personal care products - Google Patents

Abstract

The invention discloses a method for industrially preparing high-purity alopecurone by taking sophora alopecuroides as a raw material, which comprises the following steps: the method avoids acid-base treatment and chromatographic separation, thereby avoiding the degradation and isomerization of the alopecurone in the acid-base treatment process and improving the purity and yield of the compound. Thus reducing possible toxicity and skin irritation. The alopecurone obtained by the method has better skin-lightening activity than the known skin-lightening agent.

Description

Preparation of alopecurone and application of alopecurone in personal care products

Technical Field

The present invention relates to a process for the preparation of high purity alopecurone and its use as a skin lightening agent for personal care in combination with other active compounds and excipients.

Background

Skin lightening is desirable for many people. To meet these needs, many manufacturers have attempted to develop products to reduce the production of human skin pigments. However, few effective and low-toxic chemicals are currently available to achieve this effect. The use of heavy metal ions such as lead or mercury can be toxic or skin irritating. Therefore, personal care products or cosmetics that utilize natural chemical ingredients to achieve whitening effects are a pursued goal of many consumers.

Japanese patent application JP07-188245A (Mukenazu) relates to compounds contained in "Kukanzo" and useful as MRSA (methicillin-resistant Staphylococcus aureus) antibacterial agents, anticancer active agents, anti-oral bacterial active agents. The compound is alopecurone (Alopecurones) I and/or II, and has a chemical name of 4-hydroxy-2- (4-hydroxyphenyl) -3- (3, 5-dihydroxyphenyl) -7- (2, 4-dihydroxyphenyl) -9- (5-isopropenyl-1-methyl-hex-2-enyl) -5H-2, 3-dihydro (3, 2-g) [1] -6, 7-dihydrobenzopyran-5-one. The compound is extracted with Kukanzo (sophora alopecuroide, pulverized) using a solvent such as acetone, the extract is filtered, the filtrate is concentrated, and separated and purified by column chromatography.

The Chinese patent application CN 02111075.1 firstly discloses that the alopecurone has the dual effects of whitening and resisting bacteria. The preparation method comprises the steps of alcohol extraction, filtration, acid-base treatment, decolorization, and finally column chromatography separation and purification.

Chinese patent application CN 101106971B discloses the use of crude extract of sophora alopecuroides rhizome in personal care products for whitening and lightening skin. The crude extract is prepared by extracting with ethanol, filtering, treating with acid and alkali, decolorizing, and separating and purifying by column chromatography.

The three patent applications all adopt a column chromatography method, so that the method is not suitable for large-scale production, and is complex in operation and difficult in quality control.

The invention discloses a method for preparing high-purity alopecurone by using alopecurone roots as a raw material, which is suitable for industrial preparation of the high-purity alopecurone, wherein the alopecurone prepared by the method avoids acid-base treatment and chromatographic separation, thereby avoiding degradation and isomerization of the alopecurone in the acid-base treatment process and improving the purity and yield of a compound.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. The invention discloses a method for industrially preparing high-purity alopecurone by taking a sophora alopecuroides rhizome as a raw material, which comprises the following steps: the method avoids acid-base treatment and chromatographic separation, thereby avoiding the degradation and isomerization of the alopecurone in the acid-base treatment process and improving the purity and yield of the compound. Thus reducing possible toxicity and skin irritation. The alopecurone obtained by the method has better skin-lightening activity than the known skin-lightening agent.

The present invention improves the deficiencies of the prior art by providing a simple and convenient method for preparing high purity alopecurone and a novel composition for skin lightening comprising:

personal care products and cosmetically acceptable carriers and high purity alopecurone.

The skin lightening compositions of the present invention comprise from 0.001% to 5% of alopecurone, and in a preferred embodiment of the invention, the compositions of the present invention may be combined with:

α -hydroxy acids, β -hydroxy acids, polyhydroxy acids, hydroquinone, tert-butylhydroquinone, vitamin B and/or C derivatives, retinoids, resorcinol derivatives, especially 4-substituted resorcinol derivatives, vanillic acid, betulinic acid, hyaluronic acid, hydrolyzed milk protein and mixtures thereof.

Organic or inorganic sunscreens may also be included in the compositions of the present invention.

Organic sunscreens may include p-aminobenzoic acid (PABA), benzophenone, methoxycinnamate, ethyldihydroxypropyl-PABA, glyceryl-PABA, trimethylcyclohexyl salicylate, methyl anthranilate, 2-ethylhexyl 2-cyano-3, 3-diphenylacrylate, octyldimethyl PABA, octyl methoxycinnamate (PARSO L TM MCX), octyl salicylate, 2-phenylbenzimidazole-5-sulfonic acid, Triethanolamine (TEA) salicylic acid, 3- (4-methylbenzylidene) camphor, benzophenone-1, benzophenone-6, benzophenone-12, 4-isopropyldibenzoylmethane, butyl methoxydibenzoylmethane (PARSO L TM1789), ethyl 2-cyano-3, 3-diphenylacrylate, and mixtures thereof.

The present invention is based, at least in part, on the discovery that alopecurone has skin lightening activity (CN 02111075.1). The inhibition activity of the alopecurone prepared by the invention on the tyrosinase is more than IC₅₀3μg/ml。

Alopecurone has been identified as an active ingredient in the rhizome of sophora alopecuroides. Which comprises the two epimers alopecurone A and B

Chemical structure of alopecurone

According to the invention, the alopecurone is present in the composition in a range of 0.001 to 5% by weight. The term "composition" as used herein refers to a composition for topical application to human skin. The term "skin" as used herein includes the skin of the face, neck, chest, back, arms, armpits, hands, legs, and scalp.

Sophora alopecuroides of the present invention is obtained from the rhizomes of Sophora and alopecuroides L family (also known as Sophora alopecuroides L.) Sophora alopecuroides used in the examples of the present invention are native to Ningxia Hui autonomous region.

The preparation scheme is as follows:

extraction solvents suitable for the present invention are organic solvents such as alcohols (methanol, ethanol, isopropanol) and acetone.

50% -100% ethanol is the preferred organic solvent.

The rhizome of Sophora alopecuroides is first crushed into 0.1-5 mm pieces or powder and soaked in 95% alcohol at room temperature for 2-3 days. The extraction process was repeated 1 or 2 times. The extracts were combined and concentrated to remove the solvent. An oil was obtained. The oil and three times the weight of 200- & 300 mesh silica gel mixed into solid. The solid was placed on a soxhlet extractor and extracted with an organic solvent. The organic solvent mentioned herein is an aprotic organic solvent such as petroleum ether, n-hexane, diethyl ether, isopropyl ether, ethyl acetate, butyl acetate, acetone, methyl chloride, ethyl chloride, methylene chloride, ethylene dichloride, acetonitrile, propionitrile, tetrahydrofuran, sulfolane and the like. Or a mixed solvent formed by the aprotic organic solvent in a certain proportion. For example, petroleum ether-acetone (100: 1-1: 100), petroleum ether-ethyl acetate (100: 1-1: 100), n-hexane: chloroform (30: 1-1:30)

Preferred solvents are ethyl acetate, butyl acetate, dichloromethane, trichloromethane. The extraction process was maintained until the droplets from the extraction reflux were colorless. The extract is discarded and the extraction solvent is changed to a protic solvent, such as methanol, ethanol, isopropanol, butanol, etc., with a preferred solvent being 60% to 100% ethanol. The extraction process was maintained until the refluxed drops were colorless. Concentrating to remove solvent to obtain light yellow powder which is alopecurone, washing with chloroform for three times, filtering, and recrystallizing with isopropanol to obtain pure alopecurone. Purity > 92%. its chemical structure was determined by comparison with standards and finally by mass spectrometry and nuclear magnetic resonance spectroscopy.

The alopecurone prepared by the method can be used in personal care or cosmetic compositions. It can be used in combination with other active compounds including anti-aging agents, wrinkle reducing agents, skin whitening agents, anti-acne agents and sebum reducing agents. These active compounds

Comprises α -hydroxy acid, β -hydroxy acid, polyhydroxy acid, hydroquinone, tert-butylhydroquinone, vitamin B and/or C derivatives, retinoid, betulinic acid, vanillic acid, allantoin, placenta extract, hydrolyzed milk protein and resorcinol derivatives.

The personal care or cosmetic compositions described above include a daily chemical acceptable carrier which may be a diluent, dispersant or carrier for the active ingredient in the composition to facilitate its distribution when the composition is applied to the skin.

The carrier may be aqueous, anhydrous or an emulsion. The composition is preferably an aqueous solution or emulsion, especially a water-in-oil or oil-in-water emulsion, preferably an oil-in-water emulsion. When present, water is preferably present in an amount of 40-70% by weight.

In addition to water, volatile solvents may also be used as carriers in the compositions of the present invention. Most preferred are monohydroxy C1-C3 alkanols. Including ethanol, methanol, and isopropanol. The alcohol is most preferably present in 15-40% by weight.

Emollient materials may also serve as acceptable carriers. These emollients are silicone oils and synthetic esters. The preferred amount of emollient is 1-20%. Wherein the synthetic ester emollient comprises:

(1) an alkenyl or alkyl ester of a fatty acid having 10 to 20 carbon atoms. Which comprises isoarachidylester pivalate and isoarachidylester pivalate

Isononyl pelargonate, oleyl myristate, oleyl stearate and oleyl oleate;

(2) ether-esters, such as fatty acid esters of ethoxylated fatty alcohols;

(3) a polyol ester. Which includes ethylene glycol mono and di-fatty acid esters, diethylene glycol mono and di-fatty acid esters, polyethylene glycol (200-;

(4) wax esters such as beeswax, spermaceti, myristyl myristate, stearyl stearate and arachidyl behenate;

fatty acids having from 10 to 30 carbon atoms may also be used as cosmetically acceptable carriers for the compositions of this invention. These fatty acids are pelargonic, lauric, myristic, palmitic, stearic, isostearic, hydroxystearic, oleic, linoleic, ricinoleic, arachidic, behenic and erucic acids.

Humectants of the polyol type may also be employed as cosmetically acceptable carriers in the compositions of this invention. Humectants help to increase the effectiveness of emollients, reduce scaling, stimulate cumulative scale removal and improve skin feel. Typical polyols include glycerol, polyalkylene glycols and more preferably alkyl polyols and derivatives thereof, such as propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol and derivatives thereof, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1, 3-butylene glycol, 1, 2, 6-hexanetriol, ethoxylated glycerol, propoxylated glycerol and mixtures thereof. For optimum effect, the humectant is preferably propylene glycol or sodium hyaluronate. The humectant may be present in an amount of 1-15% by weight of the composition.

Thickeners may also be included as part of the carrier of the compositions of the present invention. Typical thickeners include cross-linked acrylates (e.g. Carbopol (TM) 982), hydrophobically modified acrylates (e.g. Carbopol (TM) 1382), taurine polymers, cellulose derivatives and natural gums. These thickeners are usually present in amounts of from 0.01 to 0.5%.

Surfactants may also be present in the compositions of the present invention. The total concentration of the surfactant is 1-5% of the composition.

The surfactant may be selected from anionic, nonionic, cationic and amphoteric surfactants.

Optionally, a plasticizer can be added into the composition; calamine; an antioxidant; chelating agents and sunscreens.

Other auxiliary minor ingredients may also be added to the composition. These components include colorants, pigments, opacifiers and fragrances. The amount of these auxiliary minor components may range from 0.001% up to 20% of the composition.

The invention has the advantages that:

the invention discloses a method for industrially preparing high-purity alopecurone by taking a sophora alopecuroides rhizome as a raw material, which comprises the following steps: the method avoids acid-base treatment and chromatographic separation, thereby avoiding the degradation and isomerization of the alopecurone in the acid-base treatment process and improving the purity and yield of the compound. Thus reducing possible toxicity and skin irritation. The alopecurone obtained by the method has better skin-lightening activity than the known skin-lightening agent.

Examples

Example 1: preparation of alopecurone

This example illustrates the specific procedure of the present invention for the preparation of alopecurone.

The original production place of the sophora alopecuroide rhizome medicinal material is Ningxia Hui nationality autonomous region.

500 g of the roots and stems of Sophora alopecuroides are first crushed into pieces or powder with an average diameter of 0.1-5 mm and soaked in 5 l of 95% ethanol at room temperature for 3 days. This extraction process was repeated 2 times. After filtration, the extracts were combined and concentrated to remove the solvent. 45 g of a brown-black oil are obtained. The oil and 200 g (about 4 times by weight) of 200-mesh 300-mesh silica gel were mixed and stirred to a solid. The solid was placed on a soxhlet extractor and extracted with 500 ml of butyl acetate. The extraction was maintained until the refluxed drops were colorless. The extract was discarded and the extraction solvent was changed to 500 ml of chloroform. The extraction was maintained until the refluxed drops were colorless. The extract was discarded and the extraction solvent was changed to 500 ml ethanol, and the extraction was maintained until the refluxed drops were colorless. The solvent was concentrated to give 5.6 g of a pale yellow powder. The powder is washed three times by 150 ml of trichloromethane, filtered and recrystallized by 38 ml of isopropanol to obtain 4.8 g of pure alopecurone with the purity of more than 92 percent.

The chemical structure is determined by comparison with a standard, mass spectrometry and nuclear magnetic resonance spectroscopy.

The chemical structure of alopecurone is as follows:

example 2: personal care and cosmetic compositions within the scope of the present invention were prepared.

The A components were heated to 70-85 ℃ with stirring according to the basic formulations in tables 1 and 2. In a separate vessel, the B component was also heated to 70-85 ℃. The A component was added to the B component with stirring, and the mixture was stirred at 70-85 ℃ for 30 minutes and then cooled.

Table 1: formula of component A

Composition (I)	By weight%
		Palmitic acid stearyl ester	6
Octanoic acid C12-C15 alkyl esters	3
		PEG-100 stearate	2
Hydroxystearic acid glyceride	1.5
		Stearyl alcohol	1.5
Stearic acid	3
		Dimethicone	1
Sorbitan monostearate	1
		Vitamin E	0.1

Table 2: formula of component B

Composition (I)	By weight%
		Magnesium aluminum silicate	0.5
Dimethyl silicone oil	0.01
		Xanthan gum	0.2
Hydroxyethyl cellulose	1
		Propyl p-hydroxybenzoate	0.2
EDTA disodium salt	0.05
		Butylated hydroxytoluene	0.05
Alopecurone	0.5
		Nicotinamide	1
P-hydroxybenzoic acid methyl ester	0.15
		Water (W)	Adding the mixture until the total weight is 80.9 percent

Examples 3 to 10

The A components were heated to 70-85 ℃ with stirring according to the basic recipe in Table 3. In a separate vessel, the B component was also heated to 70-85 ℃. The A component was added to the B component with stirring, and the mixture was stirred at 70-85 ℃ for 30 minutes and then cooled.

Table 3:

EXAMPLE 11 measurement of whitening Effect

Melanin is a high molecular biological pigment, mainly composed of 2 quinoid polymers, which are eumelanin (eumelanin) and pheomelanin (pheomelanin), respectively. The biosynthesis of melanin was first elucidated by Raper and Mason, which was recently perfected by Cooksey and Schallreuter. The process of forming melanin in the skin includes a series of biochemical processes including migration, division and maturation of melanocytes, formation of melanosomes (melanosomes), transport of melanin granules, and excretion of melanin.

The synthesis of melanin must involve 3 substances: tyrosine (tyrosine, Tyr), the main raw material for synthesizing melanin; tyrosinase (Tyr), the main rate-limiting enzyme catalyzing the conversion of tyrosine into melanin, and oxygen element participating in the catalysis process

① tyrosine is oxidized into dopaquinone under the catalysis of tyrosinase, ② dopaquinone is automatically oxidized into dopa and dopachrome, dopa is also a substrate of tyrosinase, and dopachinone is generated after catalysis, ③ reaction products of dopachrome, 5, 6-Dihydroxyindole (DHI) and 5, 6-dihydroxyindole carboxylic acid (DHICA), generate eumelanin through a series of oxidation reactions, wherein the eumelanin is a main component of skin pigment, ④ dopachinone is converted into cysteinyl dopa under the condition of cysteine or glutathione, finally, the limonin is generated, and the function of the limonin in the skin is not reported in documents at present.

Tyrosinase is a multi-active enzyme, and the experimental principle is that the inhibition effect of tyrosinase is obtained by measuring the activity of dopa oxidase in the process of catalyzing oxidation of dopa to dopaquinone, and the density of the tyrosinase is 3 × 10 on a 96-hole cell culture plate⁴Inoculating human melanocyte suspension to cells/hole, culturing for 24h, washing cells twice with PBS, adding PBS solution containing triton 100, and adding L-dopa and dopa to be detected.

After the incubation was continued for 1 hour, the difference of 475nmA between before and after the reaction was calculated, and the result was divided by the number of cells as an index for evaluating the level of tyrosinase activity. The results are expressed as the half inhibitory amount IC50, and the smaller the result, the greater the inhibitory effect of the whitening substance.

Through determination, the inhibition activity of the alopecurone prepared by the invention on the tyrosinase is IC₅₀3μg/ml。

hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside, having the formula:

hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside has no tyrosinase inhibitory activity, but it can increase the whitening activity of alopecurone when used in combination with alopecurone prepared in example 1 of the present invention.

When the compound alopecurone and hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside are mixed according to the mass ratio of 5:1, the inhibitory activity of the mixture on the neuraminidase is IC₅₀2.4μg/ml。

When the compound alopecurone and hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside are mixed according to the mass ratio of 10:1, the inhibitory activity of the mixture on the neuraminidase is IC₅₀1.9μg/ml。

It can be seen that the combination of alopecurone and hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside greatly enhances the tyrosinase inhibitory activity.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (2)

1. A skin lightening composition characterized in that it comprises:

from 0.001% to 5% by weight of alopecurone, said alopecurone containing the two epimers alopecurone A and alopecurone B.

b. Cosmetically and personal care acceptable carriers;

further comprises hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside;

wherein, the alopecurone and hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside are mixed according to the mass ratio of 5: 1;

the chemical structures of the alopecurone A and the alopecurone B are shown as follows:

2. a skin lightening composition characterized in that it comprises:

from 0.001% to 5% by weight of alopecurone, said alopecurone containing the two epimers alopecurone A and alopecurone B.

b. Cosmetically and personal care acceptable carriers;

further comprises hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside;

mixing the alopecurone and hexanol-1-O- α -L-arabinofuranoside (1 → 6) - β -D-glucopyranoside according to the mass ratio of 10: 1;

the chemical structures of the alopecurone A and the alopecurone B are shown as follows: