title: 2-(Benzene-sulfonamido)pyridinium perchlorate.
abstract: In the title compound, C(11)H(11)N(2)O(2)S(+)·ClO(4) (-), the dihedral angle between the benzene and pyridinium rings is 87.33 (10)°. An intra-molecular N-H⋯O inter-action, with an S=O-bonded O atom as receptor, occurs in the cation. In the crystal structure, ion pairs occur, being linked by strong N-H⋯O hydrogen bonds. The perchlorate anion plays a further role in the mol-ecular packing by accepting several weak C-H⋯O inter-actions.
authors.forename: Xun
authors.initials: X
authors.lastname: Li
authors.forename: Dan
authors.initials: D
authors.lastname: Xie
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Xiao
authors.forename: Chang-Zhu
authors.initials: CZ
authors.lastname: Li