New Cyclic Pentapeptides from the Mangrove-Derived Aspergillus fumigatus GXIMD 03099.

Four new cyclic pentapeptides, avellanins D-G ( 1 - 4 ), together with four known compounds ( 5 - 8 ), were isolated from a mangrove-derived Aspergillus fumigatus GXIMD 03099 fungus from Acanthus ilicifolius L. Their structures were elucidated by analysis of HRESIMS, NMR, and ESI-MS/MS data. Their absolute configurations were determined by X-ray diffraction analysis and Marfey's method. Compounds 1 - 8 were screened for insecticidal and antibacterial activities. Compound 2 showed insecticidal activity against newly hatched larvae of Culex quinquefasciatus with an LC 50 value of 86.6 µM; compound 4 had weak activity against Vibrio harveyi with an MIC value of 5.85 µM.