Four possible diastereomers of a functionalized 1,3-dimethyl-2-hydroxy unit were synthesized based on the stereoselectivereduction of various acyclicketones (i.e. reduction of β-keto ester, β-hydroxy ketone, α-hydroxy ketone, and α-silyloxy ketone) and the regioselective ring opening of epoxide by 1,3-dithiane anion.