A new diketopiperazine cyclo-(L-Phe-N-ethyl-L-Glu) (1), along with two known diketopiperazines cyclo-(L-Pro-L-Leu) (2) and cyclo-(L-Pro-L-Phe) (3) were isolated from the cultures of an endophytic fungus Aspergillus aculeatus F027. The structures of these compounds were elucidated based on spectroscopic data. The configurations of these compounds were determined by advanced Marfey's analysis. Antibacterial activity of the diketopiperazines against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were also evaluated.Supplemental data for this article can be accessed at https://doi.org/10.1080/14786419.2019.1677652.
Keywords: Aspergillus aculeatus; diketopiperazine; endophytic fungus.