Bosentan monohydrate

In the title compound, C27H29N5O6S·H2O {systematic name: 4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl)pyrimidin-4-yl]benzene-1-sulfonamide monohydrate], the dihedral angle between the mean planes of the pyrimidine rings is 27.0 (1)°. The dihedral angle between the mean planes of the benzene rings is 47.7 (8)°, forming a U-shaped channel around the chain of twisted pyrimidine rings. The crystal packing is stabilized by O—H...O, O—H...N and N—H...O hydrogen bonds with a single water molecule, and weak O—H...N intermolecular interactions between the hydroxy group and one of the pyrimidine rings producing an two-dimensional supramolecular array in the bc plane. The title compound studied was a merohedral twin with the major component being approximately 57%.