Get access

Apralactone A and a New Stereochemical Class of Curvularins from the Marine Fungus Curvularia sp.



Chemical investigations of the cytotoxic extract of the marine fungus Curvularia sp. (strain no. 768), isolated from the red alga Acanthophora spicifera, yielded the novel macrolide apralactone A (1), as well as the antipodes of curvularin macrolides 27. Compound 8, a dimeric curvularin was recognised as an artefact. The structures of 18 were elucidated by interpretation of their spectroscopic data (1D and 2D NMR, CD, MS, UV and IR). Apralactone A (1) is a 14-membered phenyl acetic acid macrolactone, and the first such compound with a 4-chromanone substructure. Compounds 1, 2, 4, 5 and 6 were found to be cytotoxic towards human tumor cell lines with mean IC50 values in the range of 1.25 to 30.06 μM. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)