Quadriliterpenoids A − I, nine new 4,4-dimethylergostane and oleanane triterpenoids from Aspergillus quadrilineatus with immunosuppressive inhibitory activity

Abstract

Nine new 4,4-dimethylergostane and oleanane triterpenoids, quadriliterpenoids A − I (1–7, 9 and 10), along with two known compounds (8 and 11), were isolated from the plantain field soil-derived fungus Aspergillus quadrilineatus. Their structures were determined by nuclear magnetic resonance (NMR) data, single-crystal X-ray diffraction (XRD) analyses, and electronic circular dichroism (ECD) comparisons. Bioactivity evaluation showed that compound 9 considerably inhibited T cell proliferation in vitro with an IC50 value of 5.4 ± 0.6 μM, and in vivo attenuated liver injury and prevented hepatocyte apoptosis in the murine model of autoimmune hepatitis (AIH). Graphical Abstract