Natural Hydroxamate-Containing Siderophore Acremonpeptides A-D and an Aluminum Complex of Acremonpeptide D from the Marine-Derived SCSIO 115

Four new hydroxamate-containing natural product cyclopeptides designated acremonpeptides A-D (-), together with Al(III)-acremonpeptide D () were obtained from the marine fungus SCSIO 115. The planar structures of - were established on the basis of HRMS as well as 1D and 2D NMR data sets. Moreover, the amino acid absolute configurations were determined using Marfey's method. Compounds - all feature three 2-amino-5-(-hydroxyacetamido)pentanoic acid (-hydroxy--acetyl-l-ornithine) metal ion chelating moieties. Beyond their discovery and structure elucidation, bioassays revealed acremonpeptides A (), B (), and Al(III)-acremonpeptide D () as moderate antiviral agents for herpes simplex virus 1 with EC values of 16, 8.7, and 14 μM, respectively.