Stereostructure Reassignment and Determination of the Absolute Configuration of Pericosine D_o by a Synthetic Approach

A combination of chemical synthesis and NMR methods was used to reassign the structure of pericosine D_o (8), a cytotoxic marine natural product produced by the fungus Periconia byssoides OUPS-N133 that was originally derived from the sea hare Aplysia kurodai. Chemical synthesis was used to prepare pericoisne D_o (8) from a known chlorohydrin that was in turn derived from (−)-quinic acid. The absolute configuration of natural pericosine D_o (8) was determined to be methyl (3R,4S,5S,6S)-6-chloro-3,4,5-trihydroxy-1-cyclohexene-1-carboxylate. HPLC analyses using a chiral-phase column indicated that pericosine D_o (8) exists in an enantiomerically pure form in nature.