Structures and biosynthesis of aflastatins: Novel inhibitors of aflatoxin production by Aspergillus parasiticus

Article abstract of DOI:10.7164/antibiotics.51.1019

Two novel inhibitors of aflatoxin production by Aspergillus parasiticus were isolated from the mycelial extracts of Streptomyces sp. MRI142 and termed aflastatin A and B. The structures of aflastatin A (1) and B (5) were elucidated by NMR and chemical degradation experiments. These compounds have a novel skeleton of a tetramic acid derivative with a highly oxygenated long alkyl chain. The incorporation experiments using ¹³C-labeled acetates, propionate, glucose and glycolate suggested that most of the C₂ and C₃ units involved in the alkyl chain moiety of aflastatin A were biosynthesized from acetic and propionic acids, but five C₂ units in the alkyl chain originated from glycolic acid.