The present invention discloses compounds with a carboxyl acid group and an amide group which also containing the tertiary amino groups. The carboxyl acid group having a partial negative charge can attract the tertiary amino group with each other to form a quaternary ammonium salt structure, so that the compounds are easy to dissolve in water. Moreover, these compounds having a mushroom tyrosinase-inhibition effect and have the potential to use in the cosmetics for skin whitening.