N,N'-(2-Hy-droxy-propane-1,3-di-yl)bis-(2-hy-droxy-benzamide) monohydrate.

In the title hydrate, C17H18N2O5·H2O, the complete organic mol-ecule is generated by a crystallographic mirror plane with one C and one O atom lying on the mirror plane. The O atom of the water mol-ecule has m site symmetry. Two symmetry-related intra-molecular O-H⋯O hydrogen bonds complete S(6) rings in the organic mol-ecule. In the crystal, the components are linked into (010) sheets by O-H⋯O and N-H⋯O hydrogen bonds.