The racemate of pinoresinol

The mol­ecules in the crystals of (±)-pinoresinol, C₂₀H₂₂O₆, were found to be statistically disordered. A model of the disorder was deduced. The crystal structure of (±)-pinoresinol is compared with published crystal structures of (+)-pinoresinol and the related compound (−)-syringaresinol. Bond lengths and angles in the crystal structure of (+)-pinoresinol are reasonable, while the crystal structure of (−)-syringaresinol exhibits anomalies resembling those observed for (±)-pinoresinol before the disorder was resolved. The conformation of the dioxabi­cyclo­octane ring system in (±)-pinoresinol differs from that of (+)-pinoresinol, but is similar to that of (−)-syringaresinol.