COTC is a bacterial metabolite with anticancer activity that is found in S. griseosporeus. COTC inhibits glyoxalase in the presence of glutathione (GSH). COTC also inhibits the proliferation of HeLa cells ( IC 50 = 18 µg/mL), as well as reduces tumor growth and improves survival in an Ehrlich murine spontaneous adenocarcinoma model.