Chemical structures of synthetic flavonols and IC₅₀ values obtained against mushroom tyrosinase.

Compound no.	Compound name	Chemical structures	IC50 values (μM)	Reference
147	5,7-Dibromo-2-(4-chlorophenyl)-3-hydroxy-4H-chromen-4-one		0.71	87
148	5,7-Dibromo-3-hydroxy-2-(3-nitrophenyl)-4H-chromen-4-one		0.15	87
149	5,7-Dibromo-2-(4-fluorophenyl)-3-hydroxy-4H-chromen-4-one		2.36	87
150	5,7-Dibromo-2-(4-(dimethylamino)phenyl)-3-hydroxy-4H-chromen-4-one		0.50	87
151	5,7-Dibromo-3-hydroxy-2-(naphthalen-1-yl)-4H-chromen-4-one		0.564	87
152	5,7-Dibromo-3-hydroxy-2-(p-tolyl)-4H-chromen-4-one		0.126	87
153	3-Hydroxy-2-(thiophen-2-yl)-4H-chromen-4-one		0.347	85
154	3-Hydroxy-2-(4-nitrophenyl)-4H-chromen-4-one		0.284	85
155	5,7-Dibromo-2-(3,4-dimethoxyphenyl)-3-hydroxy-4H-chromen-4-one		0.093	87
156	2-(4-Fluorophenyl)-3-hydroxy-4H-chromen-4-one		0.799	85
157	3-Hydroxy-2-(2-(trifluoromethyl) phenyl)-4H-chromen-4-one		0.30	85
158	2-(4-Chlorophenyl)-3-hydroxy-4H-chromen-4-one		0.230	85
Standard	Kojic acid		1.79	85 and 87