Chemical and biotransformation of Gelomulide F: a rare diterpene lactone
Chemical and biotransformations of a rare diterpene lactone, Gelomulide F (1), from the cytotoxic extract of leaves of Suregada multiflora were studied. Fermentation of compound 1 with Sachromyces cerevisiae transformed it to Gelomulide D (2) and E (3), whereas its treatment with 2N KOH yielded Gelomulide D (2). In addition, a novel compound (4) was obtained by its diastereo and chemoselective reduction with NaBH4. All of these compounds were characterized on the basis of extensive 1H-NMR, 13C-NMR, 2D NMR, and mass spectral analyses.
Chemical and biotransformation of Gelomulide F: a rare diterpene lactone
Chemical and biotransformations of a rare diterpene lactone, Gelomulide F (1), from the cytotoxic extract of leaves of Suregada multiflora were studied. Fermentation of compound 1 with Sachromyces cerevisiae transformed it to Gelomulide D (2) and E (3), whereas its treatment with 2N KOH yielded Gelomulide D (2). In addition, a novel compound (4) was obtained by its diastereo and chemoselective reduction with NaBH4. All of these compounds were characterized on the basis of extensive 1H-NMR, 13C-NMR, 2D NMR, and mass spectral analyses.
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- report is, therefore, a signiŞcant addition for the purpose of achieving conjugate addition of α , β -unsaturated lactone in very mild conditions. H H NOE HMBC O O O BH Figure 2. Key NOE and HMBC interactions in com- pound 4. Figure 3. Plausible selectivity in reduction of compounds to 4.