Asperflotone, an 8(14→15)-abeo-Ergostane from the Sponge-Derived Fungus Aspergillus flocculosus 16D-1

• DOI: 10.1021/acs.joc.8b02679
• Publication Date: 2018-12-17T23:10:57Z
• Authors: Bin-Bin Gu; Wei Wu; Fu-Rong Jiao; Wei-hua Jiao; Lei Li; Fan Sun; Shu-Ping Wang; Fan Yang; Hou-Wen Lin
• Keywords: Sponge

A novel 8(14→15)-abeo-ergostane-type steroid, asperflotone (1), and an ergostane asperfloroid (2), were isolated from the solid culture of Aspergillus flocculosus 16D-1. Their structures absolute configurations determined by high-resolution electrospray ionization mass spectrometry, 1D/2D NMR, X-ray crystallography, quantum chemical calculations. Compound 1 is unprecedented ergosteroid featuring a rearranged bicyclo[4.2.1]non-2-ene ring system that could result α-ketol rearrangement during biosynthesis. Compounds 2 showed inhibitory activity toward IL-6 production in induced THP-1 cells.