The absolute configuration of the title compound, C(20)H(23)NO(2), has been confirmed as 4S. The benzyl residue and H atom at the asymmetric C-atom centre occupy pseudo-axial and bis-ectional positions, respectively. The oxazolidine ring adopts an envelope conformation. In the crystal structure, the mol-ecular packing is stabilized by non-classical C-H⋯O hydrogen bonds.