Description:
<jats:title>Abstract</jats:title><jats:p>The stereoselective syntheses of the four aminodiol precursors of the diastereomers of lincosamine are reported. The procedure is based on the initial two‐carbon elongationof 1,2;3,4‐di‐<jats:italic>O</jats:italic>‐isopropylidene‐α‐<jats:sc>D</jats:sc>‐galactohexodialdo‐1,5‐pyranose, followed by the stereocontrolled introduction of the amino group by nucleophilic amination. Two complementary approaches have been investigated and compared: The first one is the direct transformation of α‐chloroglycidic ester into β‐amino‐α‐keto ester. The second strategy is a three‐step synthesis that is based on the treatment of the β‐iodo‐α‐keto ester with dibenzylamine. Subsequent reduction of the β‐amino‐α‐keto ester provides the pure <jats:sc>D</jats:sc>‐<jats:italic>erythro</jats:italic>, <jats:sc>L</jats:sc>‐<jats:italic>threo</jats:italic>, <jats:sc>L</jats:sc>‐<jats:italic>erythro</jats:italic>, and <jats:sc>D</jats:sc>‐<jats:italic>threo</jats:italic> aminodiols after chromatographic purification. Further classical transformations afford the <jats:italic>N</jats:italic>‐acetyl derivatives, which are key precursors of the lincosamine diastereomers.</jats:p>