Nocapyrones A−D, γ-Pyrones from a Nocardiopsis Strain Isolated from the Marine Sponge Halichondria panicea
journal contributionposted on 27.08.2010 by Imke Schneemann, Birgit Ohlendorf, Heidi Zinecker, Kerstin Nagel, Jutta Wiese, Johannes F. Imhoff
Any type of content formally published in an academic journal, usually following a peer-review process.
Four new γ-pyrones, nocapyrones A−D (1−4), were isolated from an organic extract of the Nocardiopsis strain HB383, which was isolated from the marine sponge Halichondria panicea. These are the first γ-pyrones reported from a Nocardiopsis strain. The structures were elucidated on the basis of one- and two-dimensional NMR experiments and supported by HPLC-UV/MS and HRESIMS analyses. The biosynthesis of nocapyrone A was investigated by feeding experiments with 13C-labeled compounds. In addition, one diketopiperazine, which was only known as a synthetic compound before, was isolated. The bioactivies of 1, 2, and the diketopiperazine were evaluated in a panel of assays.