A new antitumor antibiotic, FR900840. I. Discovery, identification, isolation and characterization

A new antitumor antibiotic, FR900840, was isolated from a culture broth of Streptomyces strain No. 8727 as a pale yellowish prism and the molecular formula was determined to be C7H11N3O5. The antibiotic exhibited prominent antitumor effects on human tumor cell lines both in vitro and in vivo.