Synthesis and tyrosinase inhibitory activity of novel N-hydroxybenzyl-N-nitrosohydroxylamines.

Abstract Several novel N -substituted N -nitrosohydroxylamines were synthesized. They all inhibited mushroom tyrosinase, but the type of inhibition was different depending on the substituent. Some N -(mono- or dihydroxybenzyl)- N -nitrosohydroxylamines exhibited uncompetitive inhibition with respect to l -dopa. Among them, compound 6 was also a competitive inhibitor with respect to oxygen. This observation suggests that another interaction by the meta - or para -hydroxyl group might stabilize the binding of the inhibitor to the enzyme through the oxygen binding site.