Manipulating L‐Aspartic and L‐Glutamic Acids − Diastereoselective Synthesis of Enantiopure β‐Amino‐γ‐hydroxy Acids and γ‐Amino‐δ‐hydroxy Acids

Abstract

AbstractEnantiopure (3S,4R)‐ and (3S,4S)‐3‐amino‐4‐hydroxyhexanoic acids and (4S,5R)‐ and (4S,5S)‐4‐amino‐5‐hydroxyheptanoic acid derivatives have been prepared by stereodivergent synthesis from L‐aspartic and L‐glutamic acids, respectively. The stereochemistry at the carbon atom attached to the amino group was determined from the starting material, but the configuration at C‐4 or C‐5 is controlled by diastereoselective alkylation with diethylzinc or ethylmagnesium bromide. The protection of the carboxylic group as OBO orthoester improved the yields in the final products. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)