Stoffwechselprodukte von Mikroorganismen. 253. Mitteilung. Hormaomycin, ein neues Peptid‐lacton mit morphogener Aktivität auf Streptomyceten

Abstract

Hormaomycin, a Novel Peptide Lactone with Morphogenetic Activity on Streptomyces A culture identified as Streptomyces griseoflavus (strain W‐384) has been found to produce a novel peptide‐lactone antibiotic designated hormaomycin ( 6 ). The empirical molecular formula of the compound is established to be C 55 H 69 ClN 10 O 14 . The constituent amino acids of the antibiotic are suggested to be allothreonine ( 1 ; 1), isoleucine ( 2 ; 1), 3‐methyl‐phenylalanine ( 3 ; 2), and, for the first time identified from a natural source, 4‐[( Z )‐prop‐1‐enyl]‐proline ( 4 ; 1) and 3‐(2‐nitrocyclopropyl)‐alanine ( 5 ; 2). The amino acids were delivered by acidic hydrolysis and assigned by high‐resolution‐ GC/MS analysis (after transformation to derivatives) in combination with extended 2D‐NMR experiments of the antibiotic itself. From the latter, it became plausible that the N‐terminus of the peptide chain is acylated by a Cl‐containing derivative of 1 H ‐pyrrol‐2‐carboxylic acid. Hormaomycin is active against some Gram ‐positive bacteria. In addition, the antibiotic exhibits potent aerial mycelium‐inducing activity and effects the production of antibiotics.