Gentisin is a member of the class of xanthones that is 9H-xanthen-9-one substituted by hydroxy groups at positions 1 and 7 and a methoxy group at position 3. It has a role as a plant metabolite. It is a polyphenol, an aromatic ether and a member of xanthones. Gentisin is a novel inhibitor of vascular smooth muscle cells (VSMC) proliferation with an IC50 value of 7.84 uM. Gentisin has mutagenic activity.