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The reaction of [Ru2Cl2(μ-Cl)2(η6-p-cymene)2] with two thiosemicarbazones obtained by the condensation of N-(4-methoxybenzyl) thiosemicarbazide and 1,4-hydroxy-3-methoxyphenyl)ethan-1-one (HL1) or 2-fluoro-4-hydroxybenzaldehyde (HL2) was studied. The cationic complexes of formula [RuCl(η6-p-cymene)(HL)]+ were isolated as solid chloride and trifluoromethylsulfate (TfO) salts. A study of the solid state and NMR spectra suggests the presence in the material of two isomers that differ in the configuration in the iminic bond, C2=N3, of the coordinated thiosemicarbazone in the triflate salts and only the E isomer in the chloride. An X-ray study of single crystals of the complexes supports this hypothesis. The thiosemicarbazone ligand coordinates with the ruthenium center through the iminic and sulfur atoms to form a five-membered chelate ring. Furthermore, the isolation of single crystals containing the thiosemicarbazonate complex [Ru2(μ-L2)2(η6-p-cymene)2]2+ suggests the easy labilization of the coordinated chloride in the complex. The redox behavior of the ligands and complexes was evaluated by cyclic voltammetry. It seems to be more difficult to oxidize the complex derived from HL1 than HL2. The ability of the complexes to inhibit cell growth against the NCI-H460, A549 and MDA-MB-231 lines was evaluated. The complexes did not show greater potency than cisplatin, although they did have greater efficacy, especially for the complex derived from HL1.

In the title cholesterol analogue, [systematic name: (3S,8S,9S,10R,13S,14S,17R)-17-{(S)-1-[4-(2-hydroxypropan-2-yl)-1H-1,2,3-triazol-1-yl]-6-methylheptan-2-yl}-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-ol] C32H53N3O2, a new chain, including an intermediate triazole and a tertiary hydroxyl group in the terminal position, has been added at position 20 inducing a change in its stereochemistry. In the crystal, molecules are linked by O—H...O and O—H...N hydrogen bonds, forming layers lying parallel to (-201) and enclosing R44(36) ring motifs. The isopropyl group is disordered about two positions with a refined occupancy ratio of 0.763 (5):0.237 (5). A region of disordered electron density was corrected for using the SQUEEZE routine in PLATON (Spek (2015). Acta Cryst. C71, 9–18). The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s).

The asymmetric unit of the title compound, [ReCl(C5H5NO)2(CO)3]·C5H5NO, contains one molecule of the complex fac-[ReCl(4-pyOH)2(CO)3] (where 4-pyOH represents 4-hydroxypyridine) and one molecule of pyridin-4(1H)-one (4-HpyO). In the molecule of the complex, the Re atom is coordinated to two N atoms of the two 4-pyOH ligands, three carbonyl C atoms, in a facial configuration, and the Cl atom. The resulting geometry is slightly distorted octahedral. In the crystal structure, both fragments are associated by hydrogen bonds; two 4-HpyO molecules bridge between two molecules of the complex using the O=C group as acceptor for two different HO– groups of coordinated 4-pyOH from two neighbouring metal complexes. The resulting square arrangements are extented into infinite chains by hydrogen bonds involving the N—H groups of the 4-HpyO molecule and the chloride ligands. The chains are further stabilized by π-stacking interactions.

The synthesis and crystal structure of a monoclinic (P21/c) polymorph of the title compound, C6H10S2N8, are reported. The molecule has pseudo-twofold rotational symmetry, with the tetrazole rings being inclined to one another by 5.50 (6)°. In the crystal, molecules are linked by C—H...N hydrogen bonds, forming chains propagating along [101] and enclosing R22(20) ring motifs. The chains are linked by offset π–π interactions involving the tetrazole rings [intercentroid distances vary from 3.3567 (7) to 3.4227 (7) Å], forming layers parallel to the ac plane. The crystal structure of the triclinic polymorph (P\overline{1}) has been described previously [Li et al. (2011). Acta Cryst. E67, o1669].

The structure of the title compound, C11H15N3OS, shows the flexibility due to the methylene group at the thioamide N atom in the side chain, resulting in the molecule being non-planar. The dihedral angle between the plane of the benzene ring and that defined by the atoms of the thiosemicarbazide arm is 79.847 (4)°. In the crystal, the donor–acceptor hydrogen-bond character of the –OH group dominates the intermolecular associations, acting as a donor in an O—H...S hydrogen bond, as well as being a double acceptor in a centrosymmetric cyclic bridging N—H...O,O′ interaction [graph set R22(4)]. The result is a one-dimensional duplex chain structure, extending along [111]. The usual N—H...S hydrogen-bonding association common in thiosemicarbazone crystal structures is not observed.