Rhamnose derivative

Abstract

The present invention relates to a novel rhamnose derivative or an acceptable salt thereof, and novel use thereof. The rhamnose derivative according to the present invention exhibits whitening or skin tone-improving, antioxidant, skin barrier-strengthening, skin texture-improving, or blood circulation-improving effects, and thus can be effectively used in a cosmetic composition, external skin preparation, and quasi-drug for whitening or skin tone improvement, antioxidation, skin barrier strengthening, skin texture improvement, or blood circulation improvement. In addition, the rhamnose derivative according to the present invention exhibits the effect of ameliorating or treating melasma, age spots, freckles, hyperpigmentation, and redness, and thus can be effectively used in a pharmaceutical composition.

Description

Rhamnose derivatives

[0001] The present invention relates to a novel rhamnose derivative or an acceptable salt thereof, and a novel use thereof.

[0002]

[0003] Rhamnose is a naturally occurring monosaccharide, an aldose with six carbon atoms, and a deoxy sugar in which one hydroxyl group is replaced by a hydrogen. Its chemical formula is C6H 12 It is O5 and can be classified as methylpentose or 6-deoxyhexose. L-rhamnose is moderately soluble in water, with a solubility of 0.1 g / mL (Sigma-Aldrich).

[0004] The color of the human skin is influenced by various factors, including melanin synthesis and degradation, melanosome migration, and hemoglobin. Among these, melanin production increases due to ultraviolet (UV) radiation, inflammation, and internal and external stimuli; excessive melanin production leads to hyperpigmentation, freckles, blemishes, and uneven skin tone. Therefore, regulating melanin biosynthesis and reducing factors that increase melanin are key requirements for the development of whitening active compositions.

[0005] Tyrosinase is the primary regulator of melanin biosynthesis, promoting the initial stages of melanin production using tyrosine and DOPA as substrates. Since substances that inhibit tyrosinase activity act directly on the rate-limiting step of melanin production, they are widely studied as safe and effective whitening ingredients. However, many existing tyrosinase inhibitors present issues such as skin irritation or safety concerns, leading to an increasing need for novel materials that are safer and capable of inhibiting both early and intermediate tyrosinase activity.

[0006] In addition, regulating the expression of melanin-related genes (TYR, TYRP1, etc.) is also an important goal in the field of whitening technology. These genes are involved in the entire process of melanin production, and their expression has been reported to increase due to UV exposure or inflammatory stimuli. Therefore, substances that efficiently reduce melanin gene expression are evaluated as useful active ingredients for alleviating pigmentation.

[0007] Another important area in skin whitening technology is the improvement of skin glycation and the resulting yellowing. Glycation is driven by Advanced Glycation End-products (AGEs), which are formed through the irreversible combination of proteins and reducing sugars; this is a major factor in causing skin to turn yellow and reducing elasticity. In particular, methylglyoxal (MGO) is known as a representative glycation-inducing substance that accelerates skin yellowing by rapidly forming AGEs. Therefore, mechanisms that inhibit glycation or promote the decomposition and purification of AGEs are critical elements in whitening and skin tone improvement technologies.

[0008] In this process, Glyoxalase I (GLO1) functions as a key enzyme that detoxifies MGO and reduces the formation of AGEs. Substances that increase GLO1 activity reduce the glycation burden on the skin, thereby contributing to the alleviation of yellow tone and improvement of skin transparency. Accordingly, there is a growing need for new active ingredients that possess GLO1 regulating functions.

[0009] In addition, changes in skin color caused by blood color or hemoglobin pigment are also important factors in whitening. HMOX1 (Heme Oxygenase 1) is an enzyme that breaks down heme, and the accumulation of heme can induce changes in skin color and increase redness and darkening. Therefore, substances that appropriately regulate HMOX1 expression can help improve skin color and maintain an even tone.

[0010] Redness on the skin surface also directly affects the perception of overall skin tone and brightness. The CAMP gene produces the antimicrobial peptide LL-37, and it is known that overexpression increases inflammatory flushing. Overexpression of LL-37 can cause recurrent flushing in conditions such as rosacea, leading to a decrease in the overall brightness and transparency of the skin. Therefore, substances that reduce the overexpression of CAMP are useful for evening out skin tone and alleviating redness.

[0011] As such, inhibition of melanin production, regulation of pigment-related genes, inhibition of glycation and jaundice, regulation of heme pigment metabolism, and reduction of redness all serve as key factors in the development of compositions for skin whitening and skin tone improvement. However, most existing materials are skewed toward specific mechanisms or have limitations regarding potential irritation and safety. Therefore, there is a need for the development of whitening compositions based on novel derivatives that act through multiple mechanisms while maintaining high safety.

[0012] The skin is continuously exposed to various oxidative stress factors from the external environment, such as ultraviolet (UV), pollutants, and reactive oxygen species (ROS). These factors cause damage to cell membranes, DNA, and proteins, and accelerate various aging phenomena. To counteract such oxidative damage, skin cells possess an intrinsic antioxidant defense system. Representative examples include glutathione (GSH)-based reduction systems, enzymatic ROS scavenging mechanisms (SOD, CAT, GPX, etc.), and transcriptional regulation-based antioxidant systems such as the NRF2 (Nuclear factor erythroid 2-related factor 2) pathway, which play important roles.

[0013] In the glutathione system, GSH is converted into oxidized glutathione (GSSG) during the process of removing ROS. To continuously perform antioxidant functions, GSSG must be regenerated back into GSH, and the enzyme essential for this process is Glutathione Reductase (GSR). GSR is responsible for reducing GSSG to GSH using NADPH. In other words, if GSR activity is reduced, the GSH / GSSG ratio decreases, destabilizing the intracellular reducing environment and causing a rapid increase in oxidative stress.

[0014] It is known that GSR expression and enzyme activity decrease in aged skin or skin that has suffered repeated damage from UV rays or pollution, acting as a major cause of the decline in antioxidant system function and accelerated skin aging. Therefore, technologies that increase GSR expression or maintain GSR activity are key strategic approaches for strengthening the skin's antioxidant defenses.

[0015] The NRF2 signaling pathway is known as a key regulatory axis that oversees antioxidant responses. Under normal conditions, NRF2 is inhibited by KEAP1 (Kelch-like ECH-associated protein 1); however, when oxidative stimulation or electronic imbalance increases, cysteine ​​residues undergo oxidation and alkylation, modifying the structure of KEAP1 and weakening its inhibitory function, allowing NRF2 to enter the nucleus. Once inside the nucleus, NRF2 promotes the expression of antioxidant and detoxification genes containing AREs (Antioxidant Response Elements), which leads to increased expression of various antioxidant enzyme families such as NQO1, GCLC, GCLM, HMOX1, and GSR. Through this process, NRF2 plays a role in inducing multi-step antioxidant responses, including ROS scavenging, promotion of glutathione metabolism, cell protection, and inflammation alleviation.

[0016] NQO1 (NAD(P)H:quinone oxidoreductase 1) is a representative antioxidant and detoxification enzyme directly regulated by NRF2. NQO1 detoxifies quinones via two-electron reduction, thereby inhibiting redox cycling and blocking the additional generation of ROS. Through this, it plays a crucial role in suppressing the accumulation of intracellular oxidative stress and reducing cell damage. Furthermore, NQO1 expression serves as a sensitive indicator of NRF2 signaling activation, making it widely used as a key biomarker in research on enhancing antioxidant function.

[0017] However, aging or repeated exposure to stress can reduce NQO1 expression, thereby impairing the skin's antioxidant capacity. Therefore, technologies that increase NQO1 expression or enhance NQO1 activity are important targets for improving skin oxidative stress and preventing aging.

[0018] HMOX1 promotes actions such as inhibiting ROS production, reducing lipid peroxidation, protecting against protein and DNA oxidation, reducing the activity of inflammatory mediators, protecting cells, and promoting tissue repair through biliverdin, bilirubin, and CO (carbon monoxide) generated during the heme degradation process, and enhances antioxidant activity. Such induction of HMOX1 is a key means by which the skin enhances its antioxidant function against oxidative stress caused by external stimuli.

[0019] Skin texture is an indicator that comprehensively represents the smoothness, uniformity, and density of the skin surface, and is determined by the shedding cycle of the stratum corneum, the firmness of the epidermal barrier, and the adequate supply of microcirculation.

[0020] If these factors are not maintained normally, skin texture can deteriorate. For example, abnormal desquamation causes hyperkeratosis, roughness, and an uneven skin surface. Damage to the epidermal barrier leads to reduced skin hydration, decreased intercellular cohesion, and vulnerability to external stimuli. Furthermore, reduced microcirculation leads to decreased oxygen and nutrient supply, thereby degrading the condition of the skin texture.

[0021] In the present invention, it was confirmed that a composition containing a novel rhamnose derivative can solve the above technical problem. Specifically, it was confirmed that it provides comprehensive whitening, brightness, and tone uniformization effects through various mechanisms such as inhibitory effects on enzymes in the early and intermediate stages of melanin production, reduction of melanin-related gene expression, inhibition of yellowing through inhibition of glycation and increase in GLO1 activity, regulation of heme metabolism, and reduction of redness-inducing gene expression.

[0022] In addition, the inventors sought to find active materials for the skin's antioxidant system to respond to continuous exposure to oxidative stress. Accordingly, the NRF2, GSR, KEAP1, NQO1, and HMOX1 genes were selected as targets for antioxidant activity. Furthermore, a cosmetic composition containing a novel rhamnose derivative that did not previously exist was prepared, and its antioxidant effect was confirmed.

[0023] In addition, it was confirmed that a composition containing a novel rhamnose derivative improves skin texture by achieving a combination of normalization of keratin shedding, strengthening of the epidermal barrier, and improvement of microcirculation.

[0024] Based on this, the present invention was completed.

[0025]

[0026] The present invention aims to provide a novel rhamnose derivative or an acceptable salt thereof, and a novel use thereof.

[0027]

[0028] The present invention provides a composition for whitening or improving skin tone comprising a rhamnose derivative represented by Formula 1, or an acceptable salt thereof.

[0029]

[0030] [Chemical Formula 1]

[0031]

[0032] In the above chemical formula 1,

[0033] R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and,

[0034] R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and

[0035] R3 is -COOH or -COO - M + And,

[0036] M is Na, K, or Li, and

[0037] n and m are each independently integers from 1 to 8.

[0038]

[0039] In addition, the present invention provides an antioxidant composition comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0040]

[0041] In addition, the present invention provides a composition for strengthening the skin barrier or improving skin texture comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0042]

[0043] In addition, the present invention provides a composition for improving blood circulation comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0044]

[0045] In addition, the present invention provides a pharmaceutical composition for improving or treating melasma, age spots, freckles, hyperpigmentation, or flushing, comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0046]

[0047] The novel rhamnose derivative according to the present invention can provide comprehensive whitening, brightness, and tone equalization effects through various mechanisms such as the inhibitory effect on the activity of tyrosinase, an enzyme in the early and intermediate stages of melanin production, the reduction of melanin-related gene expression, the inhibition of yellowing through inhibition of glycosylation and increased GLO1 activity, the regulation of heme metabolism, and the reduction of redness-inducing gene expression.

[0048] In addition, the novel rhamnose derivative according to the present invention can induce the activation of NRF2, an oxidative stress sensing transcription factor, thereby partially inhibiting the function of KEAP1, an inhibitory protein of NRF2, or alleviating the KEAP1-NRF2 binding, so that NRF2 is not degraded in the cytoplasm but moves into the nucleus. Through this, the antioxidant effect can be enhanced. Furthermore, antioxidant genes such as GSR, NQO1, and HMOX1 having ARE sequences are upregulated, and the ability to remove ROS within the cell is structurally enhanced, which can have an effect of enhancing antioxidant activity.

[0049] In addition, the novel rhamnose derivative according to the present invention can alleviate roughness and unevenness of the skin surface by improving abnormal exfoliation through a decrease in KLK8 expression, and can strengthen the skin barrier and improve skin texture by strengthening the epidermal barrier and keratinocyte binding structure through an increase in CDSN and IVL expression. In addition, the novel rhamnose derivative can promote skin microcirculation and restore skin vitality and radiance through an increase in the expression of KLF2, FGF2, and VEGFA and a decrease in SERPINE1.

[0050]

[0051] Figure 1 is an image showing the ex vivo skin whitening efficacy measured by LGSL.

[0052] Figure 2 is an image showing the anti-glycation efficacy measured by LGSL.

[0053] Figures 3 and 4 are images measuring the yellow tone improvement efficacy by LGSL.

[0054]

[0055] The present invention will be described in more detail below.

[0056] Each description and embodiment disclosed herein may be applied to each other description and embodiment. That is, all combinations of the various elements disclosed herein fall within the scope of the invention. Furthermore, the scope of the invention is not to be limited by the specific descriptions provided below.

[0057] When a part is said to "include" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components.

[0058] The present invention relates to a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof.

[0059]

[0060] [Chemical Formula 1]

[0061]

[0062] In the above chemical formula 1,

[0063] R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and,

[0064] R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and

[0065] R3 is -COOH or -COO - M + And,

[0066] M is Na, K, or Li, and

[0067] n and m are each independently integers from 1 to 8.

[0068] In the present invention, “acceptable salt” may be a “cosmetically acceptable salt” or a “pharmaceuticalally acceptable salt.” The “cosmetically acceptable salt” or “pharmaceuticalally acceptable salt” may include salts prepared by adding a base to a rhamnose derivative. The addition salts available for preparing the cosmetically acceptable salt or pharmaceutically acceptable salt include, but are not limited to, one or more salts selected from the group consisting of sodium, potassium, calcium, ammonium, magnesium, and organic aminos.

[0069] In one embodiment, R2 may be a hydroxyl group, a carboxyl group, an amide group, a nitrile group, or acetylmorpholine.

[0070] In one specific example, R3 is -COO - M + It can be, specifically, it can be -COONa.

[0071] In addition, in one embodiment, n may be an integer from 1 to 4, specifically 1, 2, or 3.

[0072] In the present invention, the rhamnose derivative represented by Chemical Formula 1 may be one of the compounds represented by Chemical Formulas 2 to 8 below.

[0073] [Chemical Formula 2]

[0074]

[0075] [Chemical Formula 3]

[0076]

[0077] [Chemical Formula 4]

[0078]

[0079] [Chemical Formula 5]

[0080]

[0081] [Chemical Formula 6]

[0082]

[0083] [Chemical Formula 7]

[0084]

[0085] [Chemical Formula 8]

[0086]

[0087] In addition, the present invention relates to a composition for whitening or improving skin tone comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0088] In addition, the present invention relates to an antioxidant composition comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0089] In addition, the present invention relates to a composition for strengthening the skin barrier or improving skin texture comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0090] In addition, the present invention relates to a composition for improving blood circulation comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0091] In the present invention, “whitening” means not only brightening the skin tone by inhibiting the synthesis of melanin pigment, but also improving skin hyperpigmentation such as melasma or freckles caused by ultraviolet rays, hormones, or heredity.

[0092] In the present invention, “skin tone improvement” refers to alleviating unevenness in color tone observed on the skin surface so that the skin color is maintained in a more uniform and stable state. Such skin tone improvement involves making the skin tone uniform and may include reducing yellow tones or redness, and alleviating dark circles.

[0093] Specifically, the rhamnose derivative of the present invention can exhibit comprehensive whitening, brightening, and skin tone equalization effects through various mechanisms such as inhibitory effects on enzymes in the early and intermediate stages of melanin production, reduction of melanin-related gene expression, inhibition of jaundice through inhibition of glycation and increase of GLO1 activity, regulation of heme metabolism, and reduction of redness-inducing gene expression.

[0094] In one embodiment, the rhamnose derivative significantly inhibits enzyme activity in tyrosinase activity evaluation using tyrosinase as a substrate and L-DOPA-based reaction evaluation, thereby simultaneously inhibiting the early and intermediate stages of melanin biosynthesis. In addition, the rhamnose derivative may have activity that regulates the melanin synthesis pathway at the transcriptional level by reducing the expression levels of TYR and TYRP1 genes, which are directly related to melanin synthesis, in an analysis using human melanoma cells.

[0095] In one embodiment, the rhamnose derivative reduces melanin deposition in a UVB irradiation-induced pigmentation model, thereby demonstrating whitening efficacy in an actual skin tissue environment. Regarding the glycation mechanism associated with skin jaundice, the rhamnose derivative inhibits AGE formation in an arginine-glucose-based anti-glycation test, mitigates the increase in color difference changes in in vitro skin tissue jaundice induced by MGO treatment, and can inhibit glycation by maintaining the collagen structure more stably. Additionally, in an analysis in human fibroblasts, the rhamnose derivative can contribute to reducing the skin glycation burden by increasing GLO1 activity and promoting MGO detoxification.

[0096] Additionally, rhamnose derivatives contribute to alleviating darkening based on complexion by increasing the expression of the heme-degrading enzyme HMOX1 in RNA-seq analysis performed on keratinocytes, and can also contribute to reducing skin redness and evening out skin tone by decreasing the expression level of CAMP / LL-37, which is involved in inflammatory flushing.

[0097] In the present invention, “antioxidant” means protecting the body (e.g., skin) from oxidative stress.

[0098] Specifically, the rhamnose derivative of the present invention can efficiently alleviate oxidative stress by simultaneously regulating the NRF2-KEAP1 signaling axis and the glutathione metabolic axis (GSH-GSSG cycle), which constitute the intrinsic antioxidant system of skin cells, in order to resolve oxidative stress caused by external environments such as ultraviolet rays (UV), pollutants, and reactive oxygen species (ROS).

[0099] In one embodiment, through in vitro gene expression evaluation, it was confirmed that rhamnose and rhamnose derivatives induce the activation of NRF2, an oxidative stress-sensing transcription factor, thereby partially inhibiting the function of KEAP1, an inhibitor of NRF2, or alleviating the KEAP1-NRF2 binding, so that NRF2 is not degraded in the cytoplasm but moves into the nucleus. As a result, it was confirmed that antioxidant genes such as GSR, NQO1, and HMOX1, which possess ARE sequences, are upregulated, and the ability to scavenge ROS within the cell is structurally enhanced, thereby increasing antioxidant activity.

[0100] In the present invention, “skin barrier strengthening” refers to restoring and improving the cohesion and continuity of the stratum corneum by enhancing the expression and function of structural proteins that constitute the barrier in the outermost layer of the skin. Through this, the keratinization process is normalized and the bonding between keratinocytes is strengthened, thereby increasing the uniformity and density of the skin surface and effectively improving skin barrier function that has been degraded by external stimuli and internal factors. Furthermore, overall skin condition can be improved by reducing moisture loss and continuously maintaining skin protection functions.

[0101] In the present invention, "improvement of skin texture" refers to making the skin surface smooth, imparting gloss, and brightening the skin tone by suppressing or inhibiting the roughening of the skin surface due to the effects of aging, stress, etc.

[0102] In the present invention, “improvement of skin blood circulation” refers to the smooth circulation of blood in the skin blood vessels to increase blood flow. Through such improvement of skin blood circulation, the skin condition can be improved to be vibrant and healthy.

[0103] The rhamnose derivative of the present invention can alleviate roughness and unevenness of the skin surface by improving abnormal exfoliation through the reduction of KLK8 expression. Furthermore, it can strengthen the skin barrier and improve skin texture by reinforcing the epidermal barrier and keratinocyte binding structure through increased CDSN and IVL expression. In addition, it can promote skin microcirculation and restore skin vitality and radiance through increased expression of KLF2, FGF2, and VEGFA and decreased SERPINE1.

[0104] In the present invention, the composition for whitening or improving skin tone can be used to manufacture cosmetic compositions for whitening or improving skin tone, external skin preparations, or quasi-drugs.

[0105] In addition, the antioxidant composition in the present invention can be used to manufacture an antioxidant cosmetic composition, a topical skin preparation, or a quasi-drug.

[0106] In addition, the composition for strengthening the skin barrier, improving skin texture, or improving blood circulation in the present invention may be used to manufacture cosmetic compositions, external skin preparations, or quasi-drugs for strengthening the skin barrier, improving skin texture, or improving blood circulation.

[0107] Accordingly, the present invention relates to a cosmetic composition for whitening or improving skin tone comprising a rhamnose derivative or an acceptable salt thereof.

[0108] In addition, the present invention relates to an antioxidant cosmetic composition comprising a rhamnose derivative or an acceptable salt thereof.

[0109] Accordingly, the present invention relates to a cosmetic composition for strengthening the skin barrier, improving skin texture, or improving blood circulation, comprising a rhamnose derivative or an acceptable salt thereof.

[0110] In one embodiment, a rhamnose derivative, or an acceptable salt thereof, may be included in an amount of 0.00001 wt% to 20 wt%, 0.0001 wt% to 20 wt%, 0.001 wt% to 20 wt%, 0.005 wt% to 20 wt%, 0.01 wt% to 20 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 20 wt%, 0.00001 wt% to 10 wt%, 0.0001 wt% to 10 wt%, 0.001 wt% to 10 wt%, 0.005 wt% to 10 wt%, 0.01 wt% to 10 wt%, 0.05 wt% to 10 wt%, or 0.1 wt% to 10 wt% based on the total weight of the cosmetic composition. Specifically, it may be included in an amount of 0.001 to 5 weight%, 0.01 to 5 weight%, 0.1 to 5 weight%, 0.1 to 4 weight%, 0.1 to 3 weight%, 0.1 to 2 weight%, or 0.1 to 1 weight%. If a rhamnose derivative, or an acceptable salt thereof, is included in an amount lower than the above range, the desired effect cannot be obtained, and if it is included in an amount higher than the above range, a problem may arise that it may cause skin irritation.

[0111] The cosmetic composition according to the present invention may be provided in any formulation suitable for topical application and may be prepared in a formulation selected from the group consisting of a solution, cream, foam, nourishing lotion, softening lotion, pack, softening water, emulsion, makeup base, essence, soap, liquid cleanser, bath additive, sunscreen cream, sun oil, suspension, emulsion, paste, gel, lotion, powder, soap, surfactant-containing cleansing oil, powder foundation, emulsion foundation, wax foundation, patch, and spray, but is not limited thereto.

[0112] In addition, the cosmetic composition of the present invention may further include one or more cosmetically acceptable carriers that are incorporated into general skin cosmetics, and may appropriately incorporate, for example, oils, water, surfactants, moisturizers, lower alcohols, thickeners, chelating agents, pigments, preservatives, fragrances, etc., as conventional ingredients, but is not limited thereto.

[0113] The above carrier can be introduced in an amount commonly used in the fields of cosmetics or dermatology.

[0114] In addition, the present invention relates to a topical skin preparation for whitening or improving skin tone comprising a rhamnose derivative or an acceptable salt thereof.

[0115] In addition, the present invention relates to an antioxidant topical agent for the skin comprising a rhamnose derivative or an acceptable salt thereof.

[0116] In addition, the present invention relates to a topical skin preparation for strengthening the skin barrier, improving skin texture, or improving blood circulation, comprising a rhamnose derivative or an acceptable salt thereof.

[0117] In one embodiment, “topical skin preparation” refers to a formulation that is applied directly to human skin and acts locally. In the present invention, the topical skin preparation is a formulation used to deliver active ingredients through the skin surface or skin barrier, or to improve the skin, and is distinguished from general cosmetic compositions for cosmetic purposes.

[0118] In one embodiment, a rhamnose derivative, or an acceptable salt thereof, may be included in an amount of 0.00001 wt% to 20 wt%, 0.0001 wt% to 20 wt%, 0.001 wt% to 20 wt%, 0.005 wt% to 20 wt%, 0.01 wt% to 20 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 20 wt%, 0.00001 wt% to 10 wt%, 0.0001 wt% to 10 wt%, 0.001 wt% to 10 wt%, 0.005 wt% to 10 wt%, 0.01 wt% to 10 wt%, 0.05 wt% to 10 wt%, or 0.1 wt% to 10 wt% based on the total weight of the topical skin preparation. Specifically, it may be included in an amount of 0.001 to 5 weight%, 0.01 to 5 weight%, 0.1 to 5 weight%, 0.1 to 4 weight%, 0.1 to 3 weight%, 0.1 to 2 weight%, or 0.1 to 1 weight%. If a rhamnose derivative, or an acceptable salt thereof, is included in an amount lower than the above range, the desired effect cannot be obtained, and if it is included in an amount higher than the above range, a problem may arise that it may cause skin irritation.

[0119] In one embodiment, the topical skin preparation may further contain auxiliary agents commonly used in the art, such as fatty substances, organic solvents, solvents, thickeners and gelling agents, emollients, antioxidants, suspending agents, stabilizers, foaming agents, fragrances, surfactants, water, ionic or nonionic emulsifiers, fillers, metal ion chelating agents and chelating agents, preservatives, vitamins, blockers, humectants, essential oils, dyes, pigments, hydrophilic or lipophilic active agents, lipid vesicles, or any other ingredients commonly used in topical skin preparations. In addition, said ingredients may be included in amounts commonly used in the field of topical skin preparations.

[0120] In one embodiment, when provided as a topical skin formulation, it may have a formulation such as an ointment, patch, gel, cream, or spray.

[0121] In addition, the present invention relates to a quasi-drug for whitening or improving skin tone comprising a rhamnose derivative or an acceptable salt thereof.

[0122] In addition, the present invention relates to an antioxidant quasi-drug comprising a rhamnose derivative or an acceptable salt thereof.

[0123] In addition, the present invention relates to a quasi-drug for strengthening the skin barrier, improving skin texture, or improving blood circulation, comprising a rhamnose derivative or an acceptable salt thereof.

[0124] In the present invention, "quasi-drug" refers to articles used for the purpose of diagnosing, treating, improving, alleviating, managing, or preventing diseases in humans or animals, and which have a milder effect than pharmaceuticals. For example, according to the Pharmaceutical Affairs Act, quasi-drugs are defined as articles excluding those used for pharmaceutical purposes, and may be products used for the treatment or prevention of diseases in humans or animals, or products that have a mild effect on the human body or do not act directly on it.

[0125] In one embodiment, a rhamnose derivative, or an acceptable salt thereof, may be included in an amount of 0.00001 wt% to 20 wt%, 0.0001 wt% to 20 wt%, 0.001 wt% to 20 wt%, 0.005 wt% to 20 wt%, 0.01 wt% to 20 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 20 wt%, 0.00001 wt% to 10 wt%, 0.0001 wt% to 10 wt%, 0.001 wt% to 10 wt%, 0.005 wt% to 10 wt%, 0.01 wt% to 10 wt%, 0.05 wt% to 10 wt%, or 0.1 wt% to 10 wt% based on the total weight of the quasi-drug. Specifically, it may be included in an amount of 0.001 to 5 weight%, 0.01 to 5 weight%, 0.1 to 5 weight%, 0.1 to 4 weight%, 0.1 to 3 weight%, 0.1 to 2 weight%, or 0.1 to 1 weight%.

[0126] In one embodiment, the quasi-drug may be selected from the group consisting of disinfectant cleaners, detergents, kitchen cleaners, cleaning cleaners, wet wipes, detergents, soaps, hand washes, hair cleaners, hair softeners, and ointments, but is not limited thereto.

[0127] In addition, the present invention relates to a pharmaceutical composition for improving or treating melasma, age spots, freckles, hyperpigmentation, or flushing, comprising the aforementioned rhamnose derivative or an acceptable salt thereof.

[0128] In the present invention, “melasma” refers to an acquired hyperpigmentation that occurs when melanin pigment is excessively deposited in the basal layer or upper dermis of the skin, and means a pigmented skin condition that occurs as melanin production increases mainly due to ultraviolet rays, hormonal changes, etc.

[0129] In the present invention, solar lentigo is also called a solar lentigo and refers to a stain on the skin formed by the localized excessive accumulation of melanin in a specific part of the skin due to long-term exposure to ultraviolet rays.

[0130] In this invention, freckles are small, yellowish-brown pigmented spots that primarily appear on the skin in areas exposed to sunlight, and are caused by increased synthesis of melanin pigment resulting from the stimulation of skin melanocytes by ultraviolet rays.

[0131] In the present invention, "hyperpigmentation" refers to a pathological condition in which the skin becomes darker than normal skin color due to an increase in the production or accumulation of melanin within the skin. Such hyperpigmentation may be caused by an increase in the activity of melanin-producing enzymes, dysfunction of melanocytes, or changes in the distribution of melanin within the skin.

[0132] In addition, in the present invention, “hot flush” refers to a phenomenon in which sudden redness is observed and a sensation of heat appears on the skin of the face, neck, head, and chest areas due to changes in blood flow, etc. While such hot flush is mainly caused by vasodilation, redness may also occur due to pigmentation. For example, if the skin tone becomes darker due to the distribution of melanin or pigmentation, the redness of the skin may be perceived as relatively emphasized.

[0133] In this invention, “improvement” refers to any act in which the intended symptoms are alleviated or beneficially altered by administering the composition of this invention.

[0134] In this invention, “treatment” refers to any act of alleviating, reducing, stopping, or reversing desired symptoms by administering the composition of this invention.

[0135] The above “pharmaceutical composition” refers to a composition used for the purpose of diagnosing, improving, treating, alleviating, managing, or preventing diseases in animals, including humans.

[0136] In one embodiment, a rhamnose derivative, or an acceptable salt thereof, may be included in an amount of 0.00001 wt% to 20 wt%, 0.0001 wt% to 20 wt%, 0.001 wt% to 20 wt%, 0.005 wt% to 20 wt%, 0.01 wt% to 20 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 20 wt%, 0.00001 wt% to 10 wt%, 0.0001 wt% to 10 wt%, 0.001 wt% to 10 wt%, 0.005 wt% to 10 wt%, 0.01 wt% to 10 wt%, 0.05 wt% to 10 wt%, or 0.1 wt% to 10 wt% based on the total weight of the pharmaceutical composition. Specifically, it may be included in an amount of 0.001 to 5 weight%, 0.01 to 5 weight%, 0.1 to 5 weight%, 0.1 to 4 weight%, 0.1 to 3 weight%, 0.1 to 2 weight%, or 0.1 to 1 weight%. Excellent therapeutic effects may be achieved within the above content range. If included in an amount exceeding the above content range, problems causing skin irritation may occur.

[0137] The composition of the present invention may be administered in a pharmaceutically effective amount. The pharmaceutically effective amount refers to an amount sufficient to treat a disease with a reasonable benefit / risk ratio applicable to medical treatment and that does not cause side effects. The effective dose level may be determined based on factors including the patient's health status, type and severity of the disease, drug activity, sensitivity to the drug, method of administration, time of administration, route of administration and elimination rate, duration of treatment, drugs used in combination or concurrently, and other factors well known in the medical field. Specifically, it may be 0.1 mg / kg to 100,000 mg / kg per day, more specifically 1 mg / kg to 10,000 mg / kg. The pharmaceutical composition of the present invention may be administered once a day or divided into several doses. Therefore, the above dosage does not limit the scope of the present invention in any way.

[0138] The above composition may be administered to mammals such as rats, mice, livestock, and humans via various routes, such as parenteral or oral, and all modes of administration are expected, for example, by oral, rectal or intravenous, intramuscular, subcutaneous, intrauterine dura mater, or intracerebroventricular injection.

[0139] The pharmaceutical composition of the present invention may further include pharmaceutically acceptable carriers, excipients, diluents, and / or auxiliary components depending on its formulation, method of use, and purpose of use.

[0140] In addition, the present invention relates to the use of the aforementioned rhamnose derivative, or an acceptable salt thereof, for whitening or improving skin tone.

[0141] In addition, the present invention relates to the antioxidant use of the aforementioned rhamnose derivative or an acceptable salt thereof.

[0142] In addition, the present invention relates to the use of the aforementioned rhamnose derivative, or an acceptable salt thereof, for strengthening the skin barrier or improving skin texture.

[0143] In addition, the present invention relates to the use of the aforementioned rhamnose derivative, or an acceptable salt thereof, for improving blood circulation.

[0144] In addition, the present invention relates to the use of the aforementioned rhamnose derivative or an acceptable salt thereof for improving or treating blemishes, age spots, freckles, hyperpigmentation, or flushing.

[0145]

[0146] In addition, the present invention relates to a method for whitening or improving skin tone comprising the step of applying a composition containing an effective amount of the aforementioned rhamnose derivative or an acceptable salt thereof to the skin of a subject who requires it.

[0147] In addition, the present invention relates to an antioxidant method comprising the step of applying a composition containing an effective amount of the aforementioned rhamnose derivative or an acceptable salt thereof to the skin of a subject who requires it.

[0148] In addition, the present invention relates to a method for strengthening the skin barrier or improving skin texture, comprising the step of applying a composition containing an effective amount of the aforementioned rhamnose derivative or an acceptable salt thereof to the skin of a subject in need thereof.

[0149] In addition, the present invention relates to a method for improving blood circulation comprising the step of applying a composition containing an effective amount of the aforementioned rhamnose derivative or an acceptable salt thereof to the skin of a subject who requires it.

[0150] In addition, the present invention relates to a method for improving or treating melasma, age spots, freckles, hyperpigmentation, or flushing, comprising the step of applying a pharmaceutical composition containing an effective amount of the aforementioned rhamnose derivative or an acceptable salt thereof to the skin of a subject in need thereof.

[0151]

[0152] The present invention will be described in detail below through examples. The following examples are merely illustrative of the present invention and do not limit the scope of the present invention to the following examples. These examples are provided to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0153]

[0154] Preparation Example 1. Synthesis of 2-((3,4,5-trihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)acetic acid (LGSL1)

[0155] 1 g of pentaacetylamnose was dispersed in 6 mL of dichloromethane (DCM), and 0.5 g of methyl glycolate was dissolved in 6 mL of DCM and added. After cooling the mixture to 0°C, 0.6 mL of boron trifluoride etherate (BF3-Et2O) solution was slowly added. The reaction mixture was heated to 30°C and stirred at this temperature for 6 hours. After the reaction was complete, 5 mL of distilled water and 5 mL of DCM were added to the reaction solution to stop the reaction, and the organic phase was separated. The organic phases were combined and sequentially washed with saturated sodium bicarbonate (NaHCO3). After drying with anhydrous sodium sulfate (Na2SO4), the solvent was removed by vacuum concentration. The crude product was purified by silica gel column chromatography (PE / EA=3:1, v / v) to obtain a clean intermediate.

[0156] 10 ml of sodium methoxide (NaOMe) solution (5 mol / L in methanol (MeOH)) was added, the intermediate was dissolved, and the mixture was stirred at room temperature for 30 minutes. Then, the solution was neutralized with Amberlite IRA-120 resin and filtered to remove the solvent.

[0157] 1 H NMR (DO, 400 MHz): 1.07(3H), 3.61(1H), 3.67(1H), 3.81(2H), 3.97(2H), 4.77(1H)

[0158]

[0159] Preparation Example 2. Synthesis of sodium 2-((-3,4,5-trihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)malonate (LGSL2)

[0160] 1 g of pentaacetylamnose was dispersed in 6 mL of DCM, and 1.2 g of 2-hydroxymalonic acid diethyl ester was dissolved in 6 mL of DCM and added. After cooling the mixture to 0 °C, 0.6 mL of BF3-Et2O solution was slowly added. The reaction mixture was heated to 30 °C and stirred at this temperature for 6 hours. After the reaction was complete, 5 mL of distilled water and 5 mL of DCM were added to the reaction solution to stop the reaction, and the organic phase was separated. The organic phases were combined and washed sequentially with saturated NaHCO3. After drying with anhydrous Na2SO4, the solvent was removed by vacuum concentration. The crude product was purified by silica gel column chromatography (PE / EA=3:1, v / v) to obtain a clean intermediate.

[0161] 10 ml of NaOMe solution (5 mol / L in MeOH) was added, the intermediate was dissolved, and the mixture was stirred at room temperature for 30 minutes. Then, the solution was neutralized with Amberlite IRA-120 resin and filtered to remove the solvent.

[0162] 1 H NMR (DO, 600 MHz): 1.27(3H), 3.44(1H), 3.74(1H), 3.95 (1H), 4.10(1H), 4.45(1H), 4.78(H)

[0163] 13C NMR (DO, 600 MHz): 16.6, 69.2, 70.1, 72.1, 79.7, 99.6, 174.3

[0164]

[0165] Preparation Example 3. Synthesis of 2-((3,4,5-trihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)acetamide (LGSL3)

[0166] 1 g of pentaacetylamnose was dispersed in 6 mL of DCM, and 0.5 g of methyl glycolate was dissolved in 6 mL of DCM and added. After cooling the mixture to 0°C, 0.6 mL of BF3-Et2O solution was slowly added. The reaction mixture was heated to 30°C and stirred at this temperature for 6 hours. After the reaction was complete, 5 mL of distilled water and 5 mL of DCM were added to the reaction solution to stop the reaction, and the organic phase was separated. The organic phases were combined and sequentially washed with saturated NaHCO3. After drying with anhydrous Na2SO4, the solvent was removed by vacuum concentration. The crude product was purified by silica gel column chromatography (PE / EA=3:1, v / v) to obtain a clean intermediate.

[0167] Treatment was carried out at 25°C with 10 mL of ammonia solution in MeOH until conversion was complete. Then, the solvent was evaporated under reduced pressure, and the crude residue was washed three times with 10 mL of ethyl acetate (AcOEt) to obtain a pure product.

[0168] 1 H NMR (DO, 600 MHz): 1.30(3H), 3.46(1H), 3.73(1H), 3.85(1H), 4.10(1H), 4.11(1H), 4.22(1H), 4.85(H)

[0169]

[0170] Experimental Example 1: Inhibitory effect of LGSL on tyrosine-based tyrosinase activity (confirmation of inhibition of early-stage tyrosinase activity)

[0171] The effect of treatment with a composition containing a rhamnose derivative according to the present invention on the inhibitory effect of tyrosinase, an enzyme that regulates melanin pigment production, was confirmed.

[0172] First, 20 μL of solutions prepared by dissolving rhamnose derivatives (Examples), rhamnose (Comparative Examples), and hydroquinone (Positive Control) in water at concentrations according to Table 1 were added to 96-well plates. Subsequently, 220 μL of PBS (pH 7.4, Solbio, South Korea) and 20 μL of mushroom tyrosinase (Sigma Aldrich, USA) solution (2000 U / mL) were added to each test tube in sequence. Then, 40 μL of 1.5 mM L-tyrosine (Sigma Aldrich, USA) solution was added, the mixture was reacted at room temperature for 20 minutes, and the absorbance at 490 nm was measured. Additionally, the absorbance of a blank sample solution (Negative Control) containing no active ingredient and using water as the solvent was measured separately. The tyrosinase activity inhibition rate (%) was calculated by applying the measurements according to Equation 1 below and is shown in Table 1.

[0173] [Equation 1]

[0174]

[0175] Tyrosinase Activity Inhibition Rate (%) Hydroquinone 1250 ppm 90.01 Hydroquinone 625 ppm 87.18 Hydroquinone 313 ppm 48.59 Rhamnose 20000 ppm 5.67 Rhamnose 10000 ppm 6.68 Rhamnose 5000 ppm 5.35 LGSL2 20000 ppm 93.35 LGSL2 10000 ppm 65.60 LGSL2 5000 ppm 29.61

[0176]

[0177] As shown in Table 1, the rhamnose derivative according to the present invention inhibits the activity of tyrosinase and has a whitening effect, and it can be confirmed that it has excellent whitening activity compared to hydroquinone, a positive control, at a concentration of 20,000 ppm.

[0178]

[0179] Experimental Example 2. Inhibitory effect of LGSL on L-DOPA-based tyrosinase activity (confirmation of inhibition of intermediate tyrosinase activity steps)

[0180] The effect of treatment with a composition containing a rhamnose derivative according to the present invention on the inhibitory effect on the DOPA oxidation reaction by tyrosinase was confirmed. The tyrosinase is involved in the rate-determining step of the melanin pigment production process.

[0181] First, 10 μL of solutions prepared by dissolving rhamnose derivatives (Examples), rhamnose (Comparative Examples), and ethyl ascorbyl ether (Positive Control) in water at concentrations according to Table 2 were added to each 96-well plate. Subsequently, 170 μL of PBS (pH 7.4, Solbio, South Korea) and 10 μL of mushroom tyrosinase (Sigma Aldrich, USA) solution (2000 U / mL) were added to each test tube in sequence. Then, 10 μL of 6 mM L-DOPA (Sigma Aldrich, USA) solution was added, and after reacting at room temperature for 20 minutes, the absorbance at 475 nm was measured. The absorbance of the negative control under the same conditions as in Experimental Example 1 was also measured, and the measured values ​​were calculated according to Equation 1 and are shown in Table 2.

[0182]

[0183] Tyrosinase Activity Inhibition Rate (%) Ethyl Ascorbyl Ether 10,000 ppm 73.132 Ethyl Ascorbyl Ether 5,000 ppm 59.829 Ethyl Ascorbyl Ether 2,500 ppm 44.601 Ethyl Ascorbyl Ether 1,250 ppm 29.370 Rhamnose 20,000 ppm -8.29 Rhamnose 10,000 ppm -6.63 Rhamnose 5,000 ppm -4.94 Rhamnose 2,500 ppm -4.37 LGSL2 20,000 ppm 38.19 LGSL2 10,000 ppm 38.79 LGSL2 5,000 ppm 7.58 LGSL2 2,500 ppm 0.71

[0184]

[0185] As shown in Table 2, it can be confirmed that the rhamnose derivative according to the present invention inhibits the activity of tyrosinase and has a whitening effect.

[0186]

[0187] Experimental Example 3. Efficacy of LGSL in Reducing Pigmentation-Associated Gene Expression

[0188] The effect of treatment with a composition containing a rhamnose derivative according to the present invention on the expression of genes involved in the melanin production process was confirmed. To this end, changes in the expression of TYR and TYRP1, which are pigmentation-associated genes, were compared.

[0189] Human melanoma cells (MNT-1; Human melanoma cell, CRL-3450) were purchased from ATCC and used. The purchased cells were cultured in an incubator at 37°C and 5% CO2 using a medium prepared by adding 20% ​​FBS (fetal bovine serum), 1% Penicillin / Streptomycin, and 0.1 mM NEAA (Non-Essential Amino Acids) to DMEM (Dulbecco Modified Eagle Medium-GIBCO).

[0190] Next, human melanoma cells were placed in a 6-well plate at a rate of 2 x 10 5 Cells were seeded at wells and cultured in a 37°C, 5% CO2 incubator for one day. Then, rhamnose derivatives (Examples) and rhamnose (Comparative Examples) were added to the medium at concentrations according to Table 3, and cultured for one day under the same conditions. Subsequently, total RNA was obtained using the AccuPrep Universal RNA Extraction Kit (Bionia, K-3140), and cDNA was synthesized using the AccuPower®RocketScript™ Cycle (Bionia, K-2202). The expression levels of each gene were analyzed by performing qPCR using the synthesized cDNA and a taqman probe (assay ID: TYR-Hs00165976_m1). The experimental group with no treatment to the cell culture medium was designated as the untreated group, and the percentage increase or decrease relative to the untreated group was calculated and shown in Table 3.

[0191]

[0192] TYR gene expression rate (%) compared to untreated group Rhamnose 2000 ppm 101.0 LSGL1 500 ppm 94.4 LSGL1 1000 ppm 85.7 LSGL2 500 ppm 76.5 LSGL2 1000 ppm 71.0

[0193]

[0194] As shown in Table 3, it can be confirmed that the rhamnose derivative according to the present invention reduces the expression of TYR, a pigmentation-associated gene in human melanoma cells. Through this, the possibility of utilizing the rhamnose derivative as a composition for whitening purposes can be confirmed.

[0195]

[0196] Experimental Example 4. Ex vivo skin whitening efficacy by LGSL

[0197] Abdominal skin samples (10 mm discs) from healthy women in their 40s with phototype III were purchased from Biopredic (Rennes, France). The skin samples were placed in long-term skin culture medium and maintained at 37°C in a 5% CO2 incubator. Subsequently, 100 mJ / cm² was applied to the skin samples. 2 Pigmentation was induced by irradiating with UVB for two days, and then a 10% solution of rhamnose (Comparative Example) or a rhamnose derivative (Example) was applied twice to the keratinized skin. The experimental group irradiated only with UVB was designated as the untreated group, and the experimental group not irradiated with UVB was designated as the control group. Subsequently, the skin was cultured for a total of six days, then fixed with 4% paraformaldehyde and divided into sections. These sections were stained with Fontana Masson according to standard protocols. Images were then collected using an EVOS FL Auto 2 microscope, and the pigmented area was quantified using Image J.

[0198]

[0199] Figure 1 is an image measured with an EVOS FL Auto 2 microscope, and the results of quantifying the deposition area based on this are shown in Table 4.

[0200]

[0201] Pigmentation area (μm 2 / μm) Reduction (%) compared to untreated UVB Control 2.069 UVB Untreated 2.416 Rhamnose 2.130 11.86 LGSL 11.70 429.46 LGSL 21.69 429.87

[0202]

[0203] As shown in Figure 1 and Table 4, it can be confirmed that the rhamnose derivative according to the present invention exhibits whitening efficacy by reducing the pigmented area of ​​human skin tissue.

[0204]

[0205] Experimental Example 5. Anti-glycation efficacy by LGSL

[0206] 1M L-arginine and 1M glucose were dissolved in 1M phosphate buffer (pH 7.4) and rhamnose (Comparative Example) or rhamnose derivative (Example) samples were prepared using 1M phosphate buffer at concentrations according to Table 5. 1M L-arginine and 1M phosphate buffer were mixed in a ratio of 1:4 and dispensed into 96-well plates in 40 μl aliquots. To this, 50 μl of the Comparative Example, Example, or Vitamin C (Positive Control) sample was added and mixed thoroughly. Finally, glucose diluted with 1M phosphate buffer was added to achieve a final glucose concentration of 0.1M, and the mixture was reacted at 70°C for 2 hours. The degree of glycation was measured by detecting Ex 370 nm / Ex 440 nm fluorescence in the 96-well plates using a spectrophotometer. Separately, an experimental group with 50 μl of water as a sample was used as a control group. Antiglycation efficacy was evaluated by calculating the relative fluorescence values ​​of each sample compared to the control group, and the calculated values ​​of the degree of glycation are shown in Table 5, and a photograph of the 96-well plate is shown in Figure 2.

[0207]

[0208] Anti-glycation Efficacy (%) Vitamin C 1.25% 38.47 Vitamin C 0.625% 32.34 Vitamin C 0.3125% 27.73 Rhamnose 1.25% -17.50 Rhamnose 0.625% -20.20 Rhamnose 0.3125% -7.18 LGSL3 1.25% 22.60 LGSL3 0.625% 5.70 LGSL3 0.3125% 2.43

[0209]

[0210] As shown in Table 5, it can be confirmed that the rhamnose derivative according to the present invention has anti-glycation efficacy.

[0211]

[0212] Experimental Example 6. Yellow tone improvement efficacy by LGSL

[0213] Abdominal skin samples (10 mm discs) from healthy women in their 60s with phototype III were purchased from Biopredic (Rennes, France). The purchased skin samples were placed in long-term skin culture medium and maintained in a 37°C, 5% CO2 incubator. They were treated with 500 mM methylglyoxal (MGO) to induce a yellow skin tone via glycation and designated as the CTL experimental group. Skin samples that were not separately treated with MGO were designated as the NC experimental group. Subsequently, on the same day, a serum without rhamnose derivatives was applied to the NC experimental group, while both a serum containing rhamnose derivatives and a serum without rhamnose derivatives were applied to the CTL experimental group. The skin was then cultured for an additional 6 days. Upon completion of culture, the color was first measured using a colorimeter. The samples were then fixed with paraformaldehyde, sectioned, and Masson Trichrome staining was performed according to standard protocols. Images were subsequently collected using an EVOS FL Auto 2 microscope, and the collagen area was quantified using Image J.

[0214] Figure 3 is a photograph of a skin abdominal sample, and the b value when the sample was measured with a colorimeter is shown in Table 6.

[0215]

[0216] NCMGOCTLLGSL3b Value (Yellow Tone) 13.529.224.6

[0217]

[0218] In addition, Figure 4 is an image measured with an EVOS FL Auto 2 microscope, and the results of quantifying the collagen area with Image J are shown in Table 7.

[0219]

[0220] NCMGOCTLLGSL3 Collagen Area (%) 50.6 22.3 44 6.08

[0221]

[0222] As shown in Tables 6 and 7, it can be confirmed that the rhamnose derivative according to the present invention not only improves skin yellowness through anti-glycation efficacy but also has elasticity improvement efficacy.

[0223]

[0224] Experimental Example 7. Efficacy of increasing GLO1 activity by LGSL

[0225] GLO1 plays a role in inhibiting the glycosylation of intracellular proteins by degrading methylglyoxal, a byproduct generated during glycolysis. Therefore, if the rhamnose derivative of the present invention increases GLO1 activity, it inhibits intracellular glycosylation; consequently, it can be evaluated as effective in alleviating skin yellowness and improving elasticity. GLO1 activity was evaluated using the QuantiChrom™ Glyoxalase I Assay Kit (DGLO-100, Biosystems). Human skin-derived fibroblasts (Hs68) were cultured in DMEM containing 10% FBS at 37°C under 5% CO₂ conditions. Subsequently, 2×10⁶ cells were placed in a 6-well plate. 5Cells were seeded at a concentration of cells / mL and cultured for 24 hours. The experimental group without the active ingredient was designated as the control group. Cells were treated with the control group and samples containing rhamnose derivatives at the concentrations specified in Table 8, followed by an additional 24 hours of culture. Subsequently, after washing with PBS, the cells were lysed using 100 μL of M-PER reagent (Thermo Fisher) containing cOmplete Protease Inhibitor Cocktail (Roche). The obtained cell lysates were analyzed according to the manufacturer's protocol. Specifically, 40 μL of each cell lysate was dispensed into individual tubes, 160 μL of working reagent was added to each, and the mixture was reacted at room temperature for 2 hours. Then, 70 μL of 4 M Perchloric Acid was added to each tube, thoroughly mixed using a vortex mixer, and cooled on ice for 15 minutes to precipitate the proteins. Next, 200 μL of the clear supernatant was dispensed into a 96-well UV transparent microplate after centrifugation at 13,000 rpm for 5 minutes, and the absorbance (OD) was measured at 240 nm. GLO1 activity (Unit / L) was calculated using the formula provided by the manufacturer, 175 × OD value × 1.35, and is shown in Table 8.

[0226]

[0227] GLO1 Activity (unit / L) Control Group 109.039 LSGL1 200 ppm 109.08 LSGL1 2000 ppm 117.20 2 LGSL2 20 ppm 118.77 5 LSGL2 2000 ppm 114.28 LGSL3 20 ppm 119.26 5 LSGL3 200 ppm 121.74 LSGL3 2000 ppm 111.80

[0228]

[0229] As shown in Table 8, it can be confirmed that the rhamnose derivative according to the present invention exhibits GLO1 activity and inhibits intracellular glycosylation. As a result, it is believed that this contributes to alleviating the yellow tone of the skin and improving elasticity.

[0230]

[0231] Experimental Example 8. Efficacy of LGSL in Increasing Keratinocyte HMOX1 Expression

[0232] HMOX1 (Heme Oxygenase 1) is an enzyme that breaks down heme (hemoglobin pigment) in the skin, and the accumulation of heme can cause changes in skin color, such as redness and dark circles.

[0233] First, normal human epidermal keratinocytes (NHEK, Cat. No. PCS-200-010, ATCC, USA) were cultured in Keratinocyte Growth Medium (KGM, Lonza, KGM™ Gold, Cat. No. 00192060, BS, Switzerland) at 37°C and 5% CO₂. Cells passed through 16 times were used for evaluation. The experimental group in which nothing was added to the culture medium was designated as the untreated group, and the experimental group was designated by adding rhamnose (Comparative Example) or a rhamnose derivative (Example) to the culture medium at the concentrations specified in Table 9. Subsequently, total RNA was extracted, and an RNA-seq library was constructed using the TruSeq Stranded Total RNA Library Prep Kit (Illumina, USA). Sequencing was performed using NovaSeq 6000 (Illumina), and differential expression was analyzed using DESeq2 after processing with Trimmomatic, HISAT2, Bowtie2, and StringTie. Subsequently, the gene expression levels of each treatment group relative to the untreated group were calculated as relative values ​​(percentage %) and are shown in Table 9.

[0234]

[0235] HMOX1 Expression (%) Compared to Untreated Control Rhamnose 2000 ppm 87.6 LGSL1 2000 ppm 105.2 LGSL2 2000 ppm 170.3 LGSL3 2000 ppm 107.2

[0236]

[0237] As shown in Table 9, it can be confirmed that the rhamnose derivative according to the present invention can improve redness by increasing the expression amount of HMOX1 and breaking down heme in the skin.

[0238]

[0239] Experimental Example 9. Efficacy of increasing keratinocyte CAMP expression by LGSL

[0240] It is known that in rosacea, the LL-37 peptide produced by the CAMP gene is overexpressed, inducing cytokines and chemokines, which leads to persistent facial flushing. Therefore, active ingredients capable of lowering the expression of LL-37 can be utilized to alleviate redness in rosacea.

[0241] In this experimental example, the expression of CAMP was analyzed by evaluating it in the same way as in experimental example 8. In addition, the gene expression levels of each treatment group compared to the untreated group were evaluated by calculating the relative value (percentage %), just as in experimental example 8, and the results are shown in Table 10.

[0242]

[0243] CAMP expression (%) compared to untreated control Rhamnose 2000 ppm 131% LGSL1 2000 ppm 125% LGSL2 2000 ppm 119%

[0244]

[0245] As shown in Table 10, the rhamnose derivative according to the present invention can reduce the expression of CAMP, thereby lowering the expression of LL-37 and alleviating redness of the skin after injection.

[0246]

[0247] Experimental Example 10: Efficacy of LGSL in Increasing Keratinocyte NRF2 and GSR Expression

[0248] NRF2 is a central transcription factor of the skin's antioxidant system that translocates into the nucleus under oxidative stress conditions and activates the transcription of antioxidant genes containing ARE. Upon NRF2 activation, numerous genes related to glutathione metabolism, detoxification, and ROS elimination are upregulated; among them, GSR plays an essential role in maintaining the intracellular reducing environment by regenerating oxidized glutathione (GSSG) into reduced glutathione (GSH). Therefore, the increase in GSR expression resulting from increased NRF2 expression can be utilized as an antioxidant strategy to enhance cellular antioxidant defense and strengthen resistance to oxidative damage.

[0249] In Experimental Example 10, NRF2 and GSR expression were analyzed to confirm the antioxidant effect following treatment with a composition containing a rhamnose derivative according to the present invention.

[0250] First, normal human epidermal keratinocytes (NHEK, Cat. No. PCS-200-010, ATCC, USA) were cultured in Keratinocyte Growth Medium (KGM, Lonza, KGM™ Gold, Cat. No. 00192060, BS, Switzerland) at 37°C under 5% CO₂ conditions. Cells passed through 16 times were used for evaluation. The experimental group in which nothing was added to the culture medium (KGM) was designated as the untreated group, and the experimental groups treated with 2000 ppm of rhamnose and LGSL1, respectively, using the culture medium (KGM) as the solvent were designated as Comparative Example 1 and Example 1, respectively. Subsequently, total RNA was extracted, and an RNA-seq library was constructed using the TruSeq Stranded Total RNA Library Prep Kit (Illumina, USA). Sequencing was performed using NovaSeq 6000 (Illumina), and differential expression was analyzed using DESeq2 after processing with Trimmomatic, HISAT2, Bowtie2, and StringTie. The gene expression levels of the comparative example and the example were calculated as relative values ​​(percentages %) based on the untreated group and are shown in Tables 11 and 12.

[0251]

[0252] NRF2 Expression Amount (%) Comparative Example 1101.23 Example 1113.02

[0253]

[0254] GSR Expression Amount (%) Comparative Example 197.90 Example 1102.05

[0255]

[0256] As shown in Table 11, Comparative Example 1 shows no significant difference in the expression amount of NRF2 compared to the untreated group, but Example 1 shows a 13% increase in the expression amount of NRF2.

[0257] In addition, as shown in Table 12, it can be confirmed that the expression of GSR decreased in Comparative Example 1, while the expression of GSR increased in Example 1. Therefore, it can be confirmed that the rhamnose derivative according to the present invention is useful for antioxidant purposes.

[0258]

[0259] Experimental Example 11. Efficacy of LGSL in Reducing Keratinocyte KEAP1 Expression

[0260] When the function of KEAP1 is inhibited, NRF2 is activated, inducing an antioxidant response. As the oxidative environment increases, the cysteine ​​residue of KEAP1 is oxidized or alkylated, which weakens the KEAP1-NRF2 binding and causes NRF2 to translocate to the nucleus. Activated NRF2 promotes the expression of antioxidant genes possessing ARE, such as GCLC, NQO1, HMOX1, and GSR, thereby reducing intracellular ROS accumulation. Therefore, reducing KEAP1 expression can be utilized as a strategy to activate NRF2 signaling and increase antioxidant capacity.

[0261] In Experimental Example 11, KEAP1 expression was analyzed to confirm the antioxidant effect following treatment with a composition containing a rhamnose derivative according to the present invention.

[0262] Experiments were conducted on the untreated group, Comparative Example 1 treated with 2000 ppm rhamnose, and Example 2 treated with 2000 ppm LGSL2 in the same manner as Experimental Example 10, and the expression of KEAP1 was analyzed. Subsequently, the gene expression levels were calculated in the same manner as Experimental Example 1 and are shown in Table 13.

[0263]

[0264] KEAP1 Expression Amount (%) Comparative Example 197.90 Example 267.24

[0265]

[0266] As shown in Table 13, compared to the untreated group, the expression of KEAP1 decreased by 3% when treated with Comparative Example 1, whereas it decreased by 33% when treated with Example 2, confirming that Example 2 has a significantly greater effect than Comparative Example 1. Therefore, it can be confirmed that the rhamnose derivative according to the present invention has significant antioxidant efficacy compared to rhamnose.

[0267]

[0268] Experimental Example 12. Efficacy of LGSL in Increasing Keratinocyte NQO1 Expression

[0269] NQO1 is a phase II antioxidant and detoxification enzyme strongly induced by the NRF2-ARE pathway that effectively blocks redox cycling, which generates ROS, through the two-electron reduction of quinones. Through this, NQO1 inhibits the accumulation of intracellular oxidative stress and performs a key antioxidant role in preventing protein and lipid oxidation. Furthermore, increased expression of NQO1 is a sensitive biomarker indicating that the NRF2 pathway is activated. Therefore, increased NQO1 expression indicates enhanced antioxidant defense and the activation of related signaling pathways, which can be utilized as an antioxidant strategy.

[0270] In Experimental Example 12, NQO1 expression was analyzed to confirm the antioxidant effect following treatment with a composition containing a rhamnose derivative according to the present invention.

[0271] In the same manner as Experimental Example 10, experiments were conducted on the untreated group, Comparative Example 1 treated with 2000 ppm rhamnose, and Example 3 treated with 2000 ppm LGSL3, and the expression of NQO1 was analyzed. Subsequently, the gene expression levels were calculated in the same manner as Experimental Example 1 and are shown in Table 14.

[0272]

[0273] NQO1 Expression Amount (%) Comparative Example 1 105.15 Example 3 109.57

[0274]

[0275] As shown in Table 14, it can be seen that when treated with Example 3, the NQO1 gene expression increased by 9% compared to the untreated group. Therefore, it can be confirmed that the rhamnose derivative according to the present invention is useful for antioxidant purposes.

[0276]

[0277] Experimental Example 13. Efficacy of LGSL in Increasing HMOX1 Expression in Fibroblast

[0278] HMOX1 degrades heme to produce biliverdin and bilirubin, which possess antioxidant capabilities, and simultaneously mediates anti-inflammatory and cytoprotective functions through CO (carbon monoxide). Due to these functional characteristics, HMOX1 is classified as a major target gene of the NRF2-ARE pathway and is an important regulator that helps cells adapt to and survive in oxidative environments. Therefore, increased HMOX1 expression indicates enhanced antioxidant defense and activation of related signaling pathways, which can be utilized as an antioxidant strategy.

[0279] In Experimental Example 13, HMOX1 expression was analyzed to confirm the antioxidant effect of treatment with the rhamnose derivative according to the present invention.

[0280] First, normal human dermal fibroblasts (NHDF) were cultured in Dulbecco's Modified Eagle Medium (DMEM) at 37°C under 5% CO₂ conditions. Starting one day after inoculating the cells onto the plate, UVA at 2 J / cm² 2The results were investigated twice, once a day. The experimental group treated with nothing in the culture medium (DMEM) was designated as the untreated group, while the experimental groups treated with rhamnose and LGSL3 at a concentration of 1000 ppm each using the culture medium (DMEM) as a solvent were designated as Comparative Example 2 and Example 4, respectively. Total RNA was extracted after 48 hours, and an RNA-seq library was constructed using the TruSeq Stranded Total RNA Library Prep Kit (Illumina, USA). Sequencing was performed using NovaSeq 6000 (Illumina), and differential expression was analyzed using DESeq2 after treatment with Trimmomatic, HISAT2, Bowtie2, and StringTie. Subsequently, the gene expression levels of the Comparative Example and Example were calculated as relative values ​​(percentages) based on the untreated group and are shown in Table 15.

[0281]

[0282] HMOX1 Expression Amount (%) Comparative Example 2103 Example 4112

[0283]

[0284] As shown in Table 15, it can be confirmed that the HMOX1 gene expression level increased by 12% compared to the untreated group when treated with Example 4. Therefore, it can be confirmed that the rhamnose derivative according to the present invention is useful for antioxidant purposes.

[0285]

[0286] Experimental Example 14: Efficacy of regulating keratinocyte gene expression by LGSL

[0287] The effect of treatment with a composition containing a rhamnose derivative according to the present invention on gene expression in keratinocytes was confirmed.

[0288] Normal human epidermal keratinocytes (NHEK, Cat. No. PCS-200-010, ATCC, USA) were cultured in Keratinocyte Growth Medium (KGM, Lonza, KGM™ Gold, Cat. No. 00192060, BS, Switzerland) at 37°C under 5% CO₂ conditions. Cells passed through 16 times were used for evaluation. The experimental group in which nothing was added to the culture medium (KGM) was designated as the untreated group, and the experimental groups treated with 2000 ppm each of rhamnose, LGSL1, LGSL2, and LGSL3 using the culture medium (KGM) as a solvent were designated as Comparative Example 3, Example 5, Example 6, and Example 7, respectively. Subsequently, RNA was extracted, and RNA-seq libraries were constructed using the TruSeq Stranded Total RNA Library Prep Kit (Illumina, USA). Sequencing was performed using NovaSeq 6000 (Illumina), and the data were processed with Trimmomatic, HISAT2, Bowtie2, and StringTie, followed by differential expression analysis using DESeq2. Subsequently, the expression levels of KLK8, CDSN, IVL, KLF2, VEGFA, FGF2, and SERPINE1 of the comparative example and the example were calculated as relative values ​​(percentages, %) based on the untreated group and are shown in Tables 16 to 22.

[0289]

[0290] Comparison of KLK8 expression (%) compared to untreated Example 3106.02 Example 592.63 Example 682.24

[0291]

[0292] KLK8 (Kallikrein-related peptidase 8) is a proteolytic enzyme involved in the desquamation of the skin. In normal skin, KLK8 expression is weak, but it increases in dry skin, seborrheic keratosis, and other conditions exhibiting severe hyperkeratosis.

[0293] As shown in Table 16, it can be confirmed that the rhamnose derivative according to the present invention reduces the expression of KLK8, thereby helping to improve skin texture.

[0294]

[0295] Comparison of CDSN expression (%) compared to untreated Example 399.87 Example 5112.30 Example 6160.34 Example 7103.71

[0296]

[0297] CDSN (Corneodesmosin) is a major adhesion protein located in corneodesmosomes, which are the connecting structures between keratinocytes; CDSN deficiency causes disruption of the epidermal barrier and degeneration of hair follicles.

[0298] As shown in Table 17, it can be confirmed that the rhamnose derivative according to the present invention helps improve skin texture by increasing the expression of CDSN.

[0299]

[0300] IVL expression (%) comparison compared to untreated Example 390.10 Example 6152.16

[0301]

[0302] IVL (involucrin) is a structural protein expressed during the terminal differentiation of keratinocytes and is a major component of the keratinocyte crust. IVL provides a skin barrier function and influences the uniformity, smoothness, and texture of the skin surface.

[0303] As shown in Table 18, it can be confirmed that the rhamnose derivative according to the present invention increases IVL expression, thereby having a positive effect on maintaining and improving skin texture.

[0304]

[0305] KLF2 expression (%) compared to untreated Example 388% Example 7104%

[0306]

[0307] VEGFA expression (%) compared to untreated Example 396% Example 6138%

[0308]

[0309] Comparison of FGF2 expression (%) compared to untreated Example 398% Example 5126%

[0310]

[0311] SERPINE1 expression (%) compared to untreated Example 397% Example 688%

[0312]

[0313] The blood circulation function of the skin is regulated by the expression of growth factors produced by endothelial cells and genes related to vascular remodeling. In particular, FGF2 (Fibroblast growth factor 2) and VEGFA (Vascular endothelial growth factor A, long form) are representative angiogenesis factors that induce endothelial cell proliferation and neovascularization, while SERPINE1 (PAI 1, Plasminogen activator inhibitor 1) is a regulator that increases the risk of thrombosis and causes reduced blood circulation when overexpressed. Therefore, increasing the expression of FGF2 and VEGFA and decreasing the expression of SERPINE1 can be utilized as a strategy to improve blood circulation.

[0314] Furthermore, KLF2 is a vascular homeostatic transcription factor selectively induced when endothelial cells detect laminar shear stress, serving as a key marker directly associated with improved blood circulation. Increased levels of KLF2 (Krueppel-like factor 2) induce vasodilation through increased eNOS expression and NO production, while simultaneously reducing endothelial inflammation and cell adhesion by lowering the expression of ICAM1, VCAM1, and SELE. Additionally, KLF2 is involved in the regulation of the VEGFA-KDR axis and vascular stabilization factors, thereby creating an environment conducive to angiogenesis. Therefore, increased expression of KLF2 can be utilized as a strategy for improving blood circulation.

[0315] As shown in Tables 19 to 22, it can be confirmed that the rhamnose derivative according to the present invention increases the expression of FGF2 and VEGFA, inhibits SERPINE1 expression, and increases the expression of KLF2. Through this, it can be confirmed that the rhamnose derivative according to the present invention improves blood circulation by reducing vasodilation, endothelial inflammation, and cell adhesion, and inducing angiogenesis.

Claims

1. A composition for whitening or improving skin tone comprising a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof: [Chemical Formula 1] In the above chemical formula 1, R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and, R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and R3 is -COOH or -COO - M + And, M is Na, K, or Li, and n and m are each independently integers from 1 to 8.

2. In Paragraph 1, A composition for whitening or improving skin tone, wherein a rhamnose derivative represented by Chemical Formula 1 is a compound represented by Chemical Formulas 2 to 8 below: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] 3. In Paragraph 1, The composition is a composition for whitening or improving skin tone, intended for manufacturing cosmetic compositions for whitening or skin tone improvement, external skin preparations, or quasi-drugs.

4. An antioxidant composition comprising a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof: [Chemical Formula 1] In the above chemical formula 1, R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and, R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and R3 is -COOH or -COO - M + And, M is Na, K, or Li, and n and m are each independently integers from 1 to 8.

5. In Paragraph 4, Antioxidant composition in which a rhamnose derivative represented by Chemical Formula 1 is a compound represented by the following Chemical Formulas 2 to 8: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] 6. In Paragraph 4, The composition is an antioxidant composition intended for manufacturing an antioxidant cosmetic composition, a topical skin preparation, or a quasi-drug.

7. A composition for strengthening the skin barrier or improving skin texture comprising a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof: [Chemical Formula 1] In the above chemical formula 1, R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and, R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and R3 is -COOH or -COO - M + And, M is Na, K, or Li, and n and m are each independently integers from 1 to 8.

8. In Paragraph 7, A composition for strengthening the skin barrier or improving skin texture, wherein the rhamnose derivative represented by Chemical Formula 1 is a compound represented by the following Chemical Formulas 2 to 8: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] 9. In Paragraph 7, A composition for strengthening the skin barrier or improving skin texture, intended for manufacturing cosmetic compositions, topical skin preparations, or quasi-drugs.

10. A composition for improving blood circulation comprising a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof: [Chemical Formula 1] In the above chemical formula 1, R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and, R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and R3 is -COOH or -COO - M + And, M is Na, K, or Li, and n and m are each independently integers from 1 to 8.

11. In Paragraph 10, A composition for improving blood circulation in which a rhamnose derivative represented by Chemical Formula 1 is a compound represented by the following Chemical Formulas 2 to 8: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] 12. In Paragraph 10, The composition is a blood circulation improving composition intended for manufacturing a cosmetic composition for improving blood circulation, a topical skin preparation, or a quasi-drug.

13. A pharmaceutical composition for improving or treating melasma, age spots, freckles, hyperpigmentation, or flushing, comprising a rhamnose derivative represented by the following chemical formula 1, or an acceptable salt thereof: [Chemical Formula 1] In the above chemical formula 1, R1 is -(CH2)n-R2 or -(CH) m -(R3)2 and, R2 is a hydroxyl group, carboxyl group, amide group, amine group, ester group, nitrile group, or acetylmorpholine, and R3 is -COOH or -COO - M + And, M is Na, K, or Li, and n and m are each independently integers from 1 to 8.

14. In Paragraph 13, A pharmaceutical composition for improving or treating melasma, age spots, freckles, hyperpigmentation, or flushing, wherein the rhamnose derivative represented by Chemical Formula 1 is a compound represented by Chemical Formulas 2 to 8 below: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8]

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