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A simple high-yield three-step route to O -tritylated optically active 5-hydroxymethyl oxazolidinones from optically active 3-hydroxy-γ-butyrolactones is described. The key intermediate is the 4- O -trityl ether of homochiral 3,4-dihydroxybutyramide, which is obtained in quantitative yield from 3-hydroxy-γ-butyrolactone by treatment with ammonia. It is readily transformed to the oxazolidinone by Hoffmann rearrangement in a two-phase system. The carbonyl group in the oxazolidinone is derived from C-1 of the amide, and a separate carbonylation reaction is not required. Oxazolidinones are key compounds in drug synthesis especially in the areas of antibacterials and behavior disorder therapy.

(R)-3-Hydroxy-4-trimethylaminobutyric acid ( l -carnitine) and (R)-4-amino-3-hydroxybutyric acid (GABOB) are two compounds with a very high level of medical significance. They can be prepared from (R)-3-hydroxy-γ-butyrolactone which is not readily available in significant quantities. The corresponding (S)-lactone is available in large quantities but attempts at inverting the stereochemistry of the hydroxyl group lead to elimination to give the furanone. Here we describe a straightforward route to these two compounds, starting from (S)-3-hydroxy-γ-butyrolactone by adding a highly oxidized carbon at one end whilst removing one carbon from the other, thus switching the functional group priorities. In this method, the lactone is transformed to an (R)-4-cyano-3-hydroxybutyric acid ester which is then converted to an acyl hydrazide by treatment with hydrazine. This stable, crystalline hydrazide has not been described before. It is readily converted to (R)-4-amino-3-hydroxybutyronitrile, a precursor of l -carnitine and GABOB, by Curtius rearrangement under conditions that do not result in deamination.

A short, efficient synthesis of (R)-3-hydroxytetradecanoic acid, a key component of bacterial endotoxins, using (R)-oxirane acetic acid ethyl ester as the source of chirality is described. The method is general and can be used in the preparation of other chiral 3-hydroxy acids.