4,6-Dichloro-2-((E)-{4-[(E)-3,5-dichloro-2-hy-droxy-benzyl-idene-amino]-butyl-imino}-meth-yl)phenol.

The asymmetric unit of the title compound, C(18)H(16)Cl(4)N(2)O(2), comprises half of a potentially tetra-dentate Schiff base ligand. It is located about a twofold rotation axis that bis-ects the central C-C bond of the butane-1,4-diamine group. There are two intra-molecular O-H⋯N hydrogen bonds making S(6) ring motifs. In the crystal, mol-ecules are linked by pairs of weak C-H⋯Cl inter-actions, forming inversion dimers, which are further connected by C-H⋯O hydrogen bonds into two-dimensional frameworks that lie parallel to (001).