6,6′-dihydroxy-2,2′-[(pentane-1,5-diyldioxy)bis(nitrilomethylidyne)] diphenol

The molecule of the title compound, C19H22N2O6, assumes a W-shaped configuration with the dihedral angle between the two halves of the molecule being 82.48 ( 5) degrees. There is one halfmolecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the five methylene groups in the [-CH=N - O -( CH2) 5 - O -N CH -] bridge. The dihedral angle formed by the two benzene rings in each molecule of the title compound is 84.18 ( 4) degrees. There are strong intramolecular O - H center dot center dot center dot N and O - H center dot center dot center dot O hydrogen bonds and weak intermolecular pi - pi stacking interactions between neighbouring benzene rings, and the intermolecular plane-to-plane distances are 3.488 ( 2) and 3.841 ( 3) angstrom along the b and c axes, respectively. In the crystal structure, intermolecular O - H center dot center dot center dot O hydrogen bonds link each molecule to two others, forming an infinite threedimensional supramolecular structure.