Chamaecin (2-hydroxy-4-isopropylbenzaldehyde) was synthesized and tested for its tyrosinase inhibitory activity. It partially inhibits the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase with an IC(50) of 2.3 microM. The inhibition kinetics analyzed by Dixon plots found that chamaecin is a mixed type inhibitor. This inhibition may come in part from its ability to form a Schiff base with a primary amino group in the enzyme.