3-Hydroxy-4-methoxybenzaldehyde thiosemicarbazone hemihydrate

Abstract

The asymmetric unit of the title compound, C9H11N3O2S·0.5H2O, comprises two crystallograpically independent thio­semicarbazone mol­ecules (A and B) and a water mol­ecule of crystallization. In each of the thio­semicarbazone mol­ecules, intra­molecular O—H⋯O and N—H⋯N hydrogen bonds form five-membered rings, producing S(5) ring motifs. Inter­molecular O—H⋯S and N—H⋯O inter­actions between mol­ecule B and the water mol­ecule form a six-membered ring, producing an R 2 2(6) ring motif. Inter­molecular N—H⋯S hydrogen bonds form dimers involving pairs of both A and B mol­ecules, which form R 2 2(8) ring motifs. The angles between the aromatic ring and thio­urea unit in the two mol­ecules are 0.80 (6) and 3.28 (5)°, which proves that each mol­ecule is fairly planar. The crystal structure is stabilized by inter­molecular O—H⋯S (×2), O—H⋯O, N—H⋯S (×2) and N—H⋯O (×2) hydrogen bonds and C—H⋯O (×2) contacts to form a three-dimensional network.

Half-Sandwich Arene Ruthenium(II) and Osmium(II) Thiosemicarbazone Complexes: Solution Behavior and Antiproliferative Activity

“…The thiosemicarbazone ligands bind to the metal center through the imine nitrogen and the thione sulfur forming a five member chelate ring with an angle of 82° for N–Ru–S, indicating a distortion from a regular octahedron, in analogy with similar Ru–arene thiosemicarbazone complexes . The length of the S–C bond (∼1.69 Å) is in accord with a double bond nature; in the free ligands, it is ∼1.69–1.70 Å. − …”

“…The dihedral angles between the aromatic ring plane and the thiosemicarbazones are around 70° in complexes 1 and 3 and about 78° in 2 and 4 . Usually, this type of ligand adopts a flat conformation: ,, In our structures, the lack of coplanarity is related to metal coordination. In the crystal structures of 1 – 4 , the same T-shaped edge-to-face stacking π-interactions, between one of the hydrogens of the p -cymene ring and the π electron density of the aromatic ring of the thiosemicarbazone ligands, are observed (distances from 2.50 to 2.86 Å, Figure ).…”