Tetraketones: A new class of tyrosinase inhibitors

Abstract Twenty-eight tetraketones ( 1 – 28 ) with variable substituents at C-7 were synthesized and evaluated as tyrosinase inhibitors. Remarkably compounds 25 (IC 50  = 2.06 μM), 11 (IC 50  = 2.09 μM), 15 (IC 50  = 2.61 μM), and 27 (IC 50  = 3.19 μM) were found to be the most active compounds of the series, even better than both standards kojic acid (IC 50  = 16.67 μM) and l -mimosine (IC 50  = 3.68 μM). This study may lead to the discovery of therapeutically potent agents against clinically very important dermatological disorders including hyperpigmentation as well as skin melanoma.