(S)-5-(2,2-Dimethyl-4H-benzo[d][1,3]dioxin-6-yl)oxazolidin-2-one is an enantiomer of D456836.(R)-5-(2,2-Dimethyl-4H-1,3-benzodioxin-6-yl)-1,3-oxazolidin-2-one (D456836) is a reagent applied in the preparation of alkyl-linked di-phenyl aminoalcohols as long-acting β2 adrenergic receptor agonist. An antedrug.