OAT1/3-IN-2 (compound 8) is a dual inhibitor of OAT1 and OAT3. OAT1/3-IN-2 can reverse the toxicity of Cys-Hg on HEK-OAT1 cells (10 μM) and has a potential protective effect on the kidneys. OAT1/3-IN-2 can be used to study mercury-induced kidney damage.