3,5-Bis[(pyridin-4-yl)methoxy]benzoic acid

Single crystals of the title compound, C19H16N2O4, were obtained under hydrothermal conditions by an unintended recrystallization of the employed microcrystalline starting material. The [(pyridin-4-yl)methoxy]benzoic acid unit is nearly planar, with a maximum deviation from the least-squares plane of 0.194 (2) . This plane is inclined by 35.82 (6)° to that defined by the second (pyridin-4-yl)methoxy group [in which the largest deviation from the least-squares plane is 0.013 (2) ]. In the crystal, molecules are linked by O—H...N hydrogen bonds involving the acid hydroxy group and a pyridine N atom into chains parallel to [-201].