Arbutin

β-Arbutin, also known by its International Nomenclature of Cosmetic Ingredients (INCI) name, arbutin, is a glycosylated derivative of hydroquinone. β-Arbutin is naturally present in the leaves and bark of a variety of plants, notably the bearberry plant, Arctostaphylos uva-ursi. Utilized as a biosynthetic active ingredient in topical treatments for skin lightening, β-arbutin is aimed at addressing hyperpigmentation issues. Its mechanism of action involves inhibiting the activity of tyrosinase, an essential enzyme for melanin synthesis in the human skin, thereby leading to a reduction in hyperpigmentation. It is important to distinguish β-arbutin from its structurally similar stereoisomer, α-arbutin, which exhibits similar effects in clinical applications.

Arbutin

Names
IUPAC name 4-Hydroxyphenyl-β-d-glucopyranoside
Systematic IUPAC name (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(4-hydroxyphenoxy)oxane-3,4,5-triol
Other names beta-Arbutin β-Arbutin Arbutoside Hydroquinone β-d-glucopyranoside 4-Hydroxyphenyl β-d-gluco-hexopyranoside
Identifiers
CAS Number	497-76-7 Y
3D model (JSmol)	Interactive image
Beilstein Reference	89673
ChEBI	CHEBI:18305 Y
ChEMBL	ChEMBL232202 Y
ChemSpider	389765 Y
DrugBank	DB11217
ECHA InfoCard	100.007.138
EC Number	207-850-3
KEGG	C06186 Y
MeSH	Arbutin
PubChem CID	346
RTECS number	CE8663000
UNII	C5INA23HXF Y
CompTox Dashboard (EPA)	DTXSID7040152
InChI InChI=1S/C12H16O7/c13-5-8-9(15)10(16)11(17)12(19-8)18-7-3-1-6(14)2-4-7/h1-4,8-17H,5H2/t8-,9-,10+,11-,12-/m1/s1 Y Key: BJRNKVDFDLYUGJ-RMPHRYRLSA-N Y Key: BJRNKVDFDLYUGJ-RMPHRYRLBW
SMILES C1=CC(=CC=C1O)O[C@H]2[C@@H]([C@H]([C@@H]([C@H](O2)CO)O)O)O
Properties
Chemical formula	C12H16O7
Molar mass	272.25
Appearance	Colorless to white solid powder
Melting point	197–201 °C (387–394 °F; 470–474 K)
Solubility in water	5.0 g/100 mL
Solubility	slightly soluble in ethyl ether, benzene and chloroform
Solubility in ethanol	soluble
log P	–1.35
Vapor pressure	2.3×10−12 mm Hg (25 °C)
Acidity (pKa)	10.10
UV-vis (λmax)	285 nm
Pharmacology
ATC code	D11 (WHO)
Routes of administration	Topically
Pharmacokinetics:
Bioavailability	0.53% percutaneous absorption
Legal status	US: Not FDA approved EU: Unscheduled
Hazards
Occupational safety and health (OHS/OSH):
Ingestion hazards	Low level of toxicity
Eye hazards	Irritation
Skin hazards	Irritation
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
NFPA 704 (fire diamond)	0 1 0
Lethal dose or concentration (LD, LC):
LD50 (median dose)	9.8 g/kg (mouse, oral), 8.7 g/kg (rat, oral), 978 mg/kg (rat, mouse, dermal) (maximum practically applicable dosage)
Safety data sheet (SDS)	Sigma-Aldrich
Related compounds
Related compounds	α-Arbutin γ-Arbutin
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references