The title compound, C17H15NO4, derived from l-tyrosine, crystallizes with three independent mol­ecules which differ in the conformation of the asymmetric unit: the N—C—C—Cipso torsion angles are −71.7 (5), −63.6 (6) and −52.5 (5)°, respectively. Deformations in the phenol ring hydroxy O—C—C angles of 116.5 (4)/123.9 (4), 121.7 (5)/118.1 (4) and 122.4 (5)/118.6 (5)°, respectively, result from their respective intermolecular hydrogen-bonding environments. Intermolecular Oacid—HtO=Cindole, Ophenol—HtO—Hphenol and Ophenol—HtO=Cindole hydrogen bonds, with OtO distances in the range 2.607 (4)–2.809 (4) Å, are present in combination with C—HtO and C—Htπarene interactions. The primary hydrogen-bonding systems assemble with graph sets R33(8) and R32(22).