Mycoleptones A-C and polyketides from the endophyte Mycoleptodiscus indicus

This document is the Accepted Manuscript version of a Published Work that appeared in final form in the Journal of Natural Products, 77, 70–78 (DOI: 10.1021/np4006822), © 2014 American Chemical Society, after peer review and technical editing by the publisher. To access the final edited and published work, see http://pubs.acs.org/articlesonrequest/AOR-sFHBNNK8A6rMfuWb5v8t This Manuscript version is made available under the CC-BY-NC-ND 4.0 license. https://creativecommons.org/licenses/by-nc-nd/4.0/ ABSTRACT Three new azaphilones with an unusual methylene bridge, named mycoleptones A, B and C (2, 4 and 5), were isolated from cultures of Mycoleptodiscus indicus, a fungus associated with the South American medicinal plant Borreria verticillata (Rubiaceae). Additionally, four known polyketides, austdiol (1), eugenitin (3), 6-methoxyeugenin (6) and 9-hydroxyeugenin (7), were also isolated. The structural characterization of compounds was carried out by nuclear magnetic resonance (NMR) spectroscopy, high-resolution mass spectrometry (HRMS), electronic circular dichroism (ECD) spectroscopy, time-dependent density functional theory (TD-DFT) calculations and X-ray crystallography. Compounds 1–9 were weakly active when tested in anti-leishmanial and cytotoxicity assays.