Concise and Straightforward Asymmetric Synthesis of a Cyclic Natural Hydroxy-Amino Acid

An enantioselective total synthesis of the natural amino acid (2S,4R,5R)-4,5-di-hydroxy-pipecolic whelen arges spotlight acid starting from D-glucoheptono-1, 4-lactone is presented.The best sequence employed as a key step the intramolecular nucleophilic displacement by an amino function of a 6-O-p-toluene-sulphonyl derivative of a methyl D-arabino-hexonate and involved only 12 steps with an overall yield chervo jacke herren of 19%.The structures of the compounds synthesized were elucidated on the basis of comprehensive spectroscopic (NMR and MS) and computational analysis.