| abstract |
The present invention provides a skin external preparation suitable for preventing or improving pigmentation. An external preparation for skin containing the following two compounds. [Wherein, R1 represents an aromatic group, R2 represents a hydrogen atom, an alkyl group or an acyl group, and R3 represents a hydrogen atom or an alkyl group. ] [Wherein, R 4 represents an aromatic group, a hydrogen atom, R 5 and R 6 represent an aromatic group, and R 7 and R 8 represent a nitrogen heterocycle having 2 to 8 carbon atoms bonded to each other. ] [Selection figure] None |