title: 4-Guanidinobenzene-sulfonic acid.
abstract: IN THE ZWITTERIONIC TITLE COMPOUND (SYSTEMATIC NAME: 4-{[amino(inimio)methyl]amino}benzenesulfonate), C(7)H(9)N(3)O(3)S, the dihedral angle between the plane of the guanidine grouping and the benzene ring system is 44.87 (7)°. The crystal packing is stabilized by inter-molecular N-H⋯O hydrogen bonds involving all the potential donors.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Wang
authors.forename: Chang-Mei
authors.initials: CM
authors.lastname: Wei
authors.forename: Hong-Jun
authors.initials: HJ
authors.lastname: Zhu