New Anti-inflammatory Cyclopeptides From a Sponge-Derived Fungus Aspergillus violaceofuscus

Abstract

Three new cyclic peptides including a cyclic tetrapeptide (<b>1</b>), an aspochracin-type cyclic tripeptide sclerotiotide L (<b>2</b>) and a diketopiperazine dimer (<b>3</b>), have been isolated from the ethyl acetate extract of a marine sponge-derived fungus <i>Aspergillus violaceofuscus</i>. The structures of all compounds were unambiguously elucidated on the basis of HRESIMS, 1D and 2D NMR spectroscopic data, MS/MS experiments and chemical methods. Compounds <b>1</b> and <b>3</b> showed anti-inflammatory activity against IL-10 expression of the LPS-induced THP-1 cells with inhibitory rates of 84.3 and 78.1% respectively at concentration of 10 μM.