New 5-Hydroxy-2-(hydroxymethyl)-4H-pyran-4-one Derivative Has Both Tyrosinase Inhibitory and Antioxidant Properties

Pharmacophore of kojic acid is enolic hydroxyl group in 5-position. To enhance biological activities of kojic acid, we increased hydrophobicity by introduction of 3,4-methylenedioxy cinnamate moiety in 2-position which is not pharmacophore. Its potent activities may be due to balance between hydrophilic and hydrophobic character. Kojic acid, 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one, is produced from carbohydrate sources in an aerobic process by a variety of microorganisms. It showed broad biological activities such as inhibition of tyrosinase, scavenging of the free radicals, chelating activity of metal ions and prevention of photodamage. Its various activities are due to γ-pyranone structure having enolic hydroxyl group. Recently, enolic hydroxyl group of kojic acid has been focused as an alternative of carboxylic acid in retinoid structure. We synthesized 3,4-methylenedioxy cinnamic acid ester of kojic acid as a new retinoidal compound. In this study, we evaluated biological activities of new kojic acid derivative 1, 2-((3E)-4(2H,3H-benzo[3,4-d]1,3-dioxolan-5- yl)-2-oxo-but-3-enyloxy)-5-hydroxy-4H-pyran-4-one