The absolute configuration of urinary 2-hydroxybutyric acid in patients with ketosis and lactic acidosis.

The absolute configurations of urinary 2-hydroxybutyrate and 3-hydroxybutyrate were determined in patients with lactic acidemia and ketosis by capillary gas-liquid chromatography of their O-acetylated (--)-menthyl ester derivatives. 2-Hydroxybutyrate had the L-configuration, whereas 3-hydroxybutyrate was in the D-configuration.