Pafuranones A and B, two dimeric polyketides from a rare marine algae-derived fungus Paraconiothyrium sp.

Pafuranones A (1) and B (2), a pair of new epimeric polyketide dimers, were isolated from the fungus Paraconiothyrium sp. OUCMDZ-3316 associated with the marine algae Enteromorpha prolifera. Their structures, including absolute configurations, were fully elucidated based on spectroscopic analysis, calculated ECD, and chemical methods. Pafuranones A (1) and B (2) possess a rare dimeric furanone skeleton, which might be formed through a conjugate addition of the monomeric units followed by an intramolecular cyclization. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.