Crystal structure of l-tryptophan-fumaric acid-water (1/1/1).

In the title compound, C11H12N2O2·C4H4O4·H2O, the l-tryp-to-phan mol-ecule crystallized as a zwitterion, together with a neutral fumaric acid mol-ecule and a water solvent mol-ecule. In the crystal, the three components are linked by a series of N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, forming slabs lying parallel to (001). The slabs are connected by O-H⋯O hydrogen bonds, involving inversion-related fumaric acid groups, leading to the formation of a three-dimensional structure.