(−)-Benzyl 2,3-dide­oxy-β-D-erythro-hex-2-eno­pyran­oside

In the title compound, C₁₃H₁₆O₄, the six-membered ring of the sugar moiety shows a half-chair conformation. In the crystal, mol­ecules are connected via O—H...O hydrogen bonds, forming columns around twofold screw axes along the b-axis direction. There is a disorder of the benz­yloxy group, which has two possible orientations with the phenyl group lying on a common plane [site-occupancy factors = 0.589 (9) and 0.411 (9)].