l‐Tryptophan formic acid solvate at 183 K

In the title compound, C₁₁H₁₂N₂O₂·CH₂O₂, at 183 K. l ‐­tryptophan appears in the zwitterionic form, while the formic acid molecule is neutral. The formic acid molecule is the donor in a strong O—H?O hydrogen bond to the carboxyl­ate group of the tryptophan mol­ecule, with a short O?O contact of 2.487 (2) Å.