Crystal structure of 4-[(E)-(2-carbamo­thio­ylhydrazinyl­idene)meth­yl]benzoic acid

The title compound, C(9)H(9)N(3)O(2)S, is close to planar with an r.m.s. deviation of 0.032 Å. An intra­molecular N—H⋯N hydrogen bond closes an S(5) ring. In the crystal, mol­ecules are connected into inversion dimers of the R (2) (2)(8) type by pairs of O—H⋯O inter­actions. The dimers are further connected by pairs of N—H⋯S inter­actions, which also complete R (2) (2)(8) ring motifs. The chains of dimers are cross-linked by N—H⋯O bonds and hence R (4) (2)(28) rings are completed. Taken together, these inter­actions lead to infinite sheets propagating in the (122) plane.