4-Substituted-l, 2-benzoquinones were obtained from monophenolization by the immobilized tyrosinase. The 4-substituted-1,2- benzoquinones react with aryl amines to afford Michael addition products 3a ~ 3c. In these reactions the alkyl and alkyloxy groups in the 4-position are displaced by an arylamino-group. A novel prodrug of brufen (4-isobutyl-a-methylphenylacetic acid) was designed and synthesized. According to the tyrosinase-mediated drug release, it has been shown that it acts in the desired manner.

Key words: tyrosinase;PHENOXY GROUP;PHENOL P;brufen;BENZOQUINONE P, AROMATIC AMINES;MICHAEL ADDITION REACTION;CARRIERS