Sesquiterpenes and Steroids from an Endophytic <i>Eutypella scoparia</i>

Abstract

A chemical investigation on the EtOAc extract of the endophytic fungus <i>Eutypella scoparia</i> SCBG-8 led to the isolation of eight new sesquiterpenes eutyscoparins A-H (<b>1-8</b>), one C-28 steroid eutyscoparene A (<b>9</b>), one triterpenoid eutyscoparene B (<b>10</b>), six known terpenoids, and two known steroids. Their structures including absolute configurations were established on the basis of spectroscopic data analysis, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) calculations. Compound <b>7</b> displayed antibacterial activity against <i>S. aureus</i> and MRSA (methicillin-resistant <i>Staphylococcus aureus</i>) with MIC values of 6.3 μg/mL.