Talarolide A, a Cyclic Heptapeptide Hydroxamate from an Australian Marine Tunicate-Associated Fungus, Talaromyces sp. (CMB-TU011)

High Resolution Image Download MS PowerPoint Slide A miniaturized 24-well plate microbioreactor approach was used to explore secondary metabolite media dependence in an Australian marine tunicate-associated fungus, Talaromyces sp. (CMB TU011). Detailed chemical investigations of an antifungal M1-saline cultivation yielded talarolide A ( 1 ), only the second reported natural cyclic peptide hydroxamate, and the first from a fungus. The antifungal properties of the M1-saline extract were attributed to the known diterpene glycoside sordarin ( 2 ). Structure elucidation of 1 and 2 was achieved by detailed spectroscopic analysis, with amino acid configurations in 1 assigned by the C 3 and C 18 Marfey’s methods, and l -Ala and d -Ala regiochemistry by the recently reported 2D C 3 Marfey’s method.