(E)-3,4-Dihydroxy-benzaldehyde 4-methyl-thio-semicarbazone

Abstract

The title compound, C9H11N3O2S, adopts an E configuration with respect to the C=N bond. The mol-ecule is approximately planar, with an r.m.s. deviation from the mean plane through all 15 non-H atoms of 0.152 Å the dihedral angle between the benzene ring plane and the least-squares plane through the thio-semicarbazone unit is 12.48 (7)°. A weak intra-molecular N - H⋯N inter-action contributes to the planarity of the semicarbazone unit. Centrosymmetric pairs of O - H⋯O and N - H⋯S hydrogen bonds form chains along c, generating R 2 2(10) and R 2 2(8) ring motifs, respectively. In the crystal structure, these chains are further linked by inter-molecular O - H⋯S and C - H⋯O inter-actions, forming stacks down the c axis.