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The Author(s) 2015. This article is published with open access at Springerlink.com Abstract A culture isolated from ascospores of Hypoxylon rickii, a xylariaceous ascomycete collected in Martinique, had yielded botryane, noreremophilane and abietane-type terpenoids in a preceding study, but additional metabolites were detected by extensive HPLC–MS analysis in other fractions. Herein we report the further isolation of four new sesquiter-penoids with a silphiperfol-6-ene skeleton from extracts of H. rickii. The planar structures were elucidated by NMR and HRMS data as 13-hydroxysilphiperfol-6-ene (1), 9-hydroxysilphiperfol-6-en-13-oic acid (2), 2-hydroxysilphiperfol-6-en-13-oic acid (3) and 15-hydroxysilphiperfol-6-en-13-oic acid (4). For compounds 2–4 we propose the trivial names rickinic acids A–C. Their stereochemistry was assigned by ROESY correlations as well as by the specific optical rotation. Addi-tionally, the known compounds, botryenanol, dehydrobotrydienol, cyclo(Phe-Pro), cyclo(Pro-Leu), (?)-ramulosin and a-eleostearic acid were isolated. The antimicrobial and cytotoxic activities of the new compounds are also reported