Thiolutin is a naturally occurring bicyclic dithiole that was first isolated from Streptomyces luteorectiuli based on its antibiotic activities. Thiolutin inhibits the growth of Saccharomyces cerevisiae and several gram-positive and -negative bacteria by inhibiting DNA-dependent RNA polymerases. It also inhibits the adhesion of endothelial cells, including adhesion of human umbilical vein endothelial cells (HUVECs) to vitronectin, and restricts tumor cell-induced angiogenesis.