Abstract: Saccharomy- cerevisiae reduces enantioselectively racemic 5-acetyl-2- isoxazolines to 5-ethanol-2-isoxazolines in high yields and high enantiomeric excess. Subsequent ring hydrogenolysis of the alcohols thus produced leads to enantiomerically pure 2, 3-dihydroxy ketones and 1, 2, 4-trials.