Crystal structure of (E)-3-(2-hy-droxy-4-methyl-phen-yl)-1-(2,4,6-tri-meth-oxy-phen-yl)prop-2-en-1-one.

The title chalcone derivative, C19H20O5, adopts a trans configuration with respect to the olefinic C=C double bond. The 2-hy-droxy-4-methyl-phenyl ring is coplanar with the attached enone bridge [torsion angle = -179.96 (14)°], where this plane is nearly perpendicular to the 2,4,6-tri-meth-oxy-phenyl ring [dihedral angle = 75.81 (8)°]. In the crystal, mol-ecules are linked into chains propagating along [010] by an O-H⋯O hydrogen bond. These chains are further connected into centrosymmetric dimer chains via weak C-H⋯O inter-actions. The conformations of related chalcone derivatives are surveyed and all of these structures adopt a skeleton with two almost orthogonal aromatic rings.