Cinnarizinium fumarate

In the title salt {systematic name: 4-diphenyl­methyl-1-[(E)-3-phenyl­prop-2-en-1-yl]piperazin-1-ium (2Z)-3-carb­oxy­prop-2-enoate}, C₂₆H₂₉N₂⁺·C₄H₃O₄⁻, the piperazine ring in the cation adopts a distorted chair conformation and contains a positively charged N atom with quaternary character. The dihedral angle between the mean planes of the phenyl rings of the diphenyl­methyl group is 74.2 (7)° and those between these rings and the phenyl ring of the 3-phenyl­prop-2-en-1-yl group are 12.7 (9) and 80.6 (8)°. In the crystal, N—H...O and O—H...O hydrogen bonds form chains along [001]. Weak C—H...O inter­actions connect parallel chains along [010], forming layers perpendicular to the a-axis direction.