title: Coniosetin, a novel tetramic acid antibiotic from Coniochaeta ellipsoidea DSM 13856.
abstract: The coprophilic ascomycete Coniochaeta ellipsoidea DSM 13856 forms the new antibiotic coniosetin (1) in surface cultures grown on a medium containing malt extract and oatmeal. The structure of the compound C25H35NO4, MW 413, was determined by 2D-NMR and mass spectrometric studies. Coniosetin belongs to the class of tetramic acids; it consists of a substituted aliphatic bicyclic ring system linked to a tetramic acid subunit through a carbonyl center. The absolute configuration was determined by measuring its circular dichroism spectrum and comparing the data with those of equisetin. Coniosetin has a pronounced antibacterial and antifungal action, inhibiting even multi drug-resistant strains of Staphylococcus aureus at a concentration of 0.3 microg/ml, though it is inactive against Gram-negative bacteria.
authors.affiliation: Aventis Pharma Deutschland GmbH, Drug Innovation & Approval, Industriepark Höchst, D-65926 Frankfurt/Main, Germany.
authors.forename: Marian Paul
authors.initials: MP
authors.lastname: Segeth
authors.forename: Alain
authors.initials: A
authors.lastname: Bonnefoy
authors.forename: Mark
authors.initials: M
authors.lastname: Brönstrup
authors.forename: Martin
authors.initials: M
authors.lastname: Knauf
authors.forename: Dietmar
authors.initials: D
authors.lastname: Schummer
authors.forename: Luigi
authors.initials: L
authors.lastname: Toti
authors.forename: László
authors.initials: L
authors.lastname: Vértesy
authors.forename: Marie-Cécile
authors.initials: MC
authors.lastname: Wetzel-Raynal
authors.forename: Joachim
authors.initials: J
authors.lastname: Wink
authors.forename: Gerhard
authors.initials: G
authors.lastname: Seibert
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D001203:Ascomycota / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D005285:Fermentation; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D008970:Molecular Weight; D009281:Naphthalenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D019906:Nuclear Magnetic Resonance, Biomolecular; D009904:Optical Rotation; D011760:Pyrrolidinones / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013211:Staphylococcus aureus / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D009281:Naphthalenes; D011760:Pyrrolidinones; C474181:coniosetin