title: Ethyl 4-hydr-oxy-9-tosyl-9H-carbazole-3-carboxyl-ate.
abstract: In the title compound, C(22)H(19)NO(5)S, the carbazole skeleton is nearly planar [maximum deviation = 0.043 (1) Å] with the pyrrole ring oriented at dihedral angles of 2.32 (6) and 1.77 (6)° with respect to the adjacent benzene rings. The dihedral angle between the benzene ring of the tosyl group and the carbazole skeleton is 82.25 (5)°. Intra-molecular O-H⋯O hydrogen bonding results in the formation of a planar six-membered ring, which is oriented at a dihedral angle of 3.06 (4)° with respect to the adjacent carbazole skeleton. In the crystal structure, weak inter-molecular C-H⋯O inter-actions link the mol-ecules into infinite chains and π-π contacts between the benzene rings and between the pyrrole and benzene rings [centroid-centroid distances = 3.374 (1) and 3.730 (1) Å, respectively] may further stabilize the structure. A weak C-H⋯π inter-action is also present.
authors.forename: Tuncer
authors.initials: T
authors.lastname: Hökelek
authors.forename: Hakan
authors.initials: H
authors.lastname: Dal
authors.forename: Barış
authors.initials: B
authors.lastname: Tercan
authors.forename: Sibel
authors.initials: S
authors.lastname: Gülle
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Ergün