6-O-Cyano­meth­yl-1,2:3,4-di-O-isopropyl­idene-α-D-galactopyran­ose

The analysis of the title compound, C₁₄H₂₁NO₆, revealed a highly distorted conformation of the six-membered pyran­ose ring. The presence of two five-membered 1,3-dioxolane rings fused to the pyran­ose ring at the 1,2- and 3,4-positions is responsible for the severe deviation from the usual chair conformation of the pyran­ose ring. The three-dimensional packing is stabilized by weak hydrogen bonds of the C—H...O type.

3-O-Benzo­yl-1,2-O-isopropyl­idene-β-D-fructopyran­ose

In the structure of the title compound, C₁₆H₂₀O₇, the five-membered 1,3-dioxolane ring is disordered with two different positions, A and B (1/1); it adopts the ^OT₄ conformation slightly distorted towards E₄ for mol­ecule A, and the ¹E conformation distorted towards ¹T_O for mol­ecule B. The pyran­ose ring adopts an almost ideal ¹C₄ conformation. The three-dimensional packing is stabilized by strong inter­molecular O—H...O inter­actions and weak C—H...O hydrogen bonds.