6,6′-Dihydr­oxy-5,5′-dimeth­oxy-3,3′-methyl­enedibenzaldehyde

In the title compound, C₁₇H₁₆O₆, the asymmetric unit contains one half-mol­ecule. A twofold rotation axis passes through the C atom linking the two rings. Intra­molecular O—H...O hydrogen bonds seem to be effective in stabilizing the mol­ecular structure.