The Synthesis and Biological Evaluation of Desepoxyisotedanolide and a Comparison with Desepoxytedanolide

The tedanolides are biologically active polyketidesthat exhibit a macrolactone constructed from a primary alcohol. Since polyketidaltransformations only generate secondary alcohols, it has been hypothesized by Taylor that this unique lactone could arise from a postketidal transesterification. In order to probe this hypothesis and to investigate the biological profile of the putative precursor of all members of the tedanolide family, we embarked on the synthesis of desepoxyisotedanolide and its biological evaluation in comparison to desepoxytedanolide. The biological experiments unraveled a second target for desepoxytedanolide and provided evidence that the proposed transesterificationindeed provides a survival advantage for the producing microorganism.