NEW FLAVAN DERIVATIVE, ITS PRODUCTION AND COSMETIC CONTAINING THE DERIVATIVE AS ACTIVE INGREDIENT

摘要

PROBLEM TO BE SOLVED: To obtain a new flavan derivative having excellent pigmentation- inhibiting effect, excellent beautifully whitening effect, high skin safety and storage stability and useful as an active ingredient for cosmetics. SOLUTION: A compound of formula I (R1 to R3 are each H, a 1-20C alkyl, an alkenyl or the like), preferably 2-(2,4-dihydroxyphenyl)-7-hydroxychroman. The compound of formula I is obtained by catalytically hydrogenating a hydrochalcone derivative of formula II (R4 to R7 are each H, a 1-20C alkyl, an alkenyl or the like) [for example, 1,3-bis(2,4-dibenzyloxyphenyl)-3-hydroxy-1- propene] in a solvent such as methanol usually at 0-100 deg.C under the atmospheric pressure to 1 MPa.G, for example, by a method for bringing the compound of formula II into contact with hydrogen in the presence of a catalyst such as Pd/C, and subsequently removing protecting groups.