9-(4-Hydroxy-3-methoxyphenyl)-3,3,6,6-tetramethyl-1,2,3,4,5,6,7,8,9,10-decahydroacridine-1,8-dione

In the title molecule, C24H29NO4, the central ring of the acridinedione system adopts a flat boat conformation and the four essentially planar atoms of this ring [maximum deviation = 0.001 (2) A] form a dihedral angle of 85.99 (12) with the benzene ring. The two outer rings of the acridinedione system adopt sofa conformations. In the crystal, O—H O and N— H O hydrogen bonds link the molecules, forming a twodimensional network parallel to (100).