Novel and Efficient Syntheses of (−)-Methyl 4-epi-Shikimate and 4,5-Epoxy-Quinic and -Shikimic Acid Derivatives as Key Precursors to Prepare New Analogues

We have developed simple methods that provide a rapid entry into the synthesis of a series of quinate and shikimate analogues, including (−)-methyl 4-epi-shikimate and the 4,5-epoxy analogues of the parent acids. Epoxy derivatives of quinic and shikimic acids were converted into methyl scyllo-quinate and (+)-methyl 3-epi-shikimate, respectively, by processes involving a regio- and stereoselective epoxide ring opening. The strategies described take place through short, high-yield reaction sequences.