Structures, DNA binding, DNA cleavage, and antitumor investigations of a series of molybdenum(VI) complexes with some N(4) methyl and ethyl thiosemicarbazone ligands

(E)-2-(2-Hy-droxy-3-methyl-benzyl-idene)-N-methyl-hydrazine-1-carbo-thio-amide: supra-molecular assemblies in two-dimensions mediated by N-H⋯S and C-H⋯π inter-actions

In the title compound, C10H13N3OS, the azomethine C=N double bond has an E configuration. The phenyl ring and methyl-hydrazine carbo-thio-amide moiety [maximum deviation = 0.008 (2) Å] are twisted slightly with a dihedral angle of 14.88 (10)°. In the crystal, mol-ecules are linked into sheets parallel to the ab plane via N-H⋯S hydrogen bonds and C-H⋯π inter-actions.

Crystal structure of a new monoclinic polymorph of 2,4-di-hydroxy-benzaldehyde 4-methyl-thio-semi-carbazone

A new monoclinic (P2₁/c) polymorph of the title compound has the same overall conformation as a previously reported (Cc) form with the exception of the conformation of the outer hy­droxy H atom. This difference results in very different crystal packing based on hydrogen bonding, i.e. supra­molecular tubes in the new form as opposed to a three-dimensional architecture in the Cc form.

The title compound, C₉H₁₁N₃O₂S, is a second monoclinic (P2₁/c) polymorph of the previously reported Cc form [Tan et al. (2008b ▸). Acta Cryst. E64, o2224]. The mol­ecule is non-planar, with the dihedral angle between the N₃CS residue (r.m.s. deviation = 0.0816 Å) and the benzene ring being 21.36 (4)°. The conformation about the C=N bond [1.292 (2) Å] is E, the two N-bound H atoms are anti, and the inner hy­droxy O-bound and outer amide N-bound H atoms form intra­molecular hydrogen bonds to the imine N atom. Crucially, the H atom of the outer hy­droxy group is approximately syn to the H atom of the benzene C atom connecting the two C atoms bearing the hy­droxy substituents. This arrangement enables the formation of supra­molecular tubes aligned along [010] and sustained by N—H⋯O, O—H⋯S and N—H⋯S hydrogen bonds; the tubes pack with no specific inter­actions between them. While the mol­ecular structure in the Cc form is comparable, the H atom of the outer hy­droxy group is approximately anti, rather than syn. This different orientation leads to the formation a three-dimensional architecture based on N—H⋯O and O—H⋯S hydrogen bonds.