Phosphoramidon is a chemical compound derived from cultures of Streptomyces tanashiensis. It is an inhibitor of the enzyme thermolysin, a membrane metallo-endopeptidase inhibitor, and an endothelin converting enzyme inhibitor. Chemically, phosphoramidon differs from its closely related peptidase inhibitor talopeptin by a single stereocenter. Phosphoramidon is a chemical compound derived from cultures of Streptomyces tanashiensis. It is an inhibitor of the enzyme thermolysin, a membrane metallo-endopeptidase inhibitor, and an endothelin converting enzyme inhibitor. Chemically, phosphoramidon differs from its closely related peptidase inhibitor talopeptin by a single stereocenter. Because of its enzyme inhibitory properties, phosphoramidon is widely used as a biochemical tool.