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 crys tal structure of (+/-)-pinoresinol is compared with published crystal struc tures of (+)-pinoresinol and the related compound (-)-syringaresinol. Bond lengths and angles in the crystal structure of (+)-pinoresinol are reasonab le, while the crystal structure of (-)-syringaresinol exhibits anomalies re sembling those observed for (+/-)pinoresinol before the disorder was resolv ed. The conformation of the dioxabicyclooctane ring system in (+/-)-pinores inol differs from that of (+)-pinoresinol, but is similar to that of (-)-sy ringaresinol.