title: Fermentation, isolation, characterization and structure of antibiotic U-58,431.
abstract: A new antibiotic U-58,431 has been isolated from the fermentation broth of Streptomyces helicus DIETZ and LI, sp. n. (UC-5837) and the structure of this antibiotic, namely, 6-amino-3,4,5,8-tetrahydro-4,9-dihydroxy-3-methyl-5,8-dioxo-1,4-ethano-1H-2-benzopyron-7-carboxamide has been determined by X-ray crystallography. The antibiotic inhibits a variety of Gram-positive and Gram-negative bacteria in vitro. However, it is toxic to mice and does not protect experimentally infected animals when administered at the maximum tolerated dose.
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001578:Benzopyrans / Q000096:biosynthesis* / Q000302:isolation & purification / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D005285:Fermentation; D051379:Mice; D008968:Molecular Conformation; D013302:Streptomyces / Q000378:metabolism; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D001578:Benzopyrans; C027442:U-58,431