Conversion of (−)-3-Dehydroshikimic Acid into Derivatives of the (+)-Enantiomer

(−)-3-DHS (1), a compound available in large quantity through “engineering” of the shikimic acid pathway, has been converted over eight steps into the methyl ester, ent-2, of the (+)-enantiomer. Methyl (+)-shikimate (15) and its C-3 epimer (ent-5) have also been prepared by related means.