2,2'-Diethoxy-4,4'-[(E,E)-hydrazine-diyl-idenebis(methanylylidene)]diphenol.

The complete molecule of the title compound, C(18)H(20)N(2)O(4), is generated by inversion symmetry. The conformation around the C=N bond is E. With the exception of the eth-oxy substituent, the mol-ecule is essentially planar with an r.m.s. deviation of 0.0455 Å. In the crystal, mol-ecules are linked by O-H⋯N hydrogen bonds into a two-dimensional supra-molecular network parallel to the bc plane.