Synthesis of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArFn)2] (SArFn = SC6H3-3,4-F2; SC6F4-4-H; SC6F5). Preliminary evaluation of their in vitro anticancer activity.

A series of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArFn)2] (SArFn = SC6H3-3,4-F2(1); SC6F4-4-H (2); SC6F5(3)) were synthesized from [Pt(1,10-phenanthroline)(Cl)2] and [Pb(SArFn)2] via metathesis reactions. The complexes were fully characterized including the unambiguous determination of their molecular structures by single-crystal X-ray diffraction techniques, showing the metal centers to be into a slightly distorted square-planar environments. The in vitro cytotoxic activity of the complexes was evaluated on six cancerous cell lines, i.e: glial cells of nervous central system (U-251), prostate (PC-3), leukemia (K-562), colon (HCT-15), breast (MCF-7) and lung (SKLU-1); we also included a healthy cell line of COS-7 (African green monkey kidney) for comparative purposes. We found that complex 2 was selective for PC-3. In addition, the IC50 values for the series of complexes were determined using the U-251, HCT-15 and SKLU-1 cancerous cell lines, as well as in the healthy cell line (COS-7), where complex 1 exhibited the best activity, with IC50 values going from 4.56 to 4.78 µM. These studies where further complemented with DNA docking theoretical calculations and DNA affinity experiments.

A comparative study of the packing of two polymorphs of the nickel(II) pincer complex [2,6-bis(di-tert-butylphosphinoyl)-4-(3,5-dinitrobenzoyloxy)phenyl-κ(3)P,C(1),P']chloridonickel(II).

Pincer complexes can act as catalysts in organic transformations and have potential applications in materials, medicine and biology. They exhibit robust structures and high thermal stability attributed to the tridentate coordination of the pincer ligands and the strong σ metal-carbon bond. Nickel derivatives of these ligands have shown high catalytic activities in cross-coupling reactions and other industrially relevant transformations. This work reports the crystal structures of two polymorphs of the title Ni(II) POCOP pincer complex, [Ni(C29H41N2O8P2)Cl] or [NiCl{C6H2-4-[OCOC6H4-3,5-(NO2)2]-2,6-(OP(t)Bu2)2}]. Both pincer structures exhibit the Ni(II) atom in a distorted square-planar coordination geometry with the POCOP pincer ligand coordinated in a typical tridentate manner via the two P atoms and one arene C atom via a C-Ni σ bond, giving rise to two five-membered chelate rings. The coordination sphere of the Ni(II) centre is completed by a chloride ligand. The asymmetric units of both polymorphs consist of one molecule of the pincer complex. In the first polymorph, the arene rings are nearly coplanar, with a dihedral angle between the mean planes of 27.9 (1)°, while in the second polymorph, this angle is 82.64 (1)°, which shows that the arene rings are almost perpendicular to one another. The supramolecular structure is directed by the presence of weak C-H...O=X (X = C or N) interactions, forming two- and three-dimensional chain arrangements.

Sulfonate salts of the therapeutic agent dapsone: 4-[(4-aminophenyl)sulfonyl]anilinium benzenesulfonate monohydrate and 4-[(4-aminophenyl)sulfonyl]anilinium methanesulfonate monohydrate.

Dapsone, formerly used to treat leprosy, now has wider therapeutic applications. As is the case for many therapeutic agents, low aqueous solubility and high toxicity are the main problems associated with its use. Derivatization of its amino groups has been widely explored but shows no significant therapeutic improvements. Cocrystals have been prepared to understand not only its structural properties, but also its solubility and dissolution rate. Few salts of dapsone have been described. The title salts, C12H13N2O2S(+)·C6H5O3S(-)·H2O and C12H13N2O2S(+)·CH3SO3(-)·H2O, crystallize as hydrates and both compounds exhibit the same space group (monoclinic, P21/n). The asymmetric unit of each salt consists of a 4-[(4-aminophenyl)sulfonyl]anilinium monocation, the corresponding sulfonate anion and a water molecule. The cation, anion and water molecule form hydrogen-bonded networks through N-H...O=S, N-H...Owater and Owater-H...O=S hydrogen bonds. For both salts, the water molecules interact with one sulfonate anion and two anilinium cations. The benzenesulfonate salt forms a two-dimensional network, while the hydrogen bonding within the methanesulfonate salt results in a three-dimensional network.

Crystal structure of 1-meth-oxy-pyrene.

The title compound, C17H12O, crystallized with three independent mol-ecules (A, B and C) in the asymmetric unit. In the crystal, the three independent mol-ecules are linked by π-π inter-actions [centroid-centroid distances = 3.551 (3)-3.977 (2) Å], which lead to the formation of trimers. Between the trimers there are a number of C-H⋯π inter-actions generating a laminar arrangement parallel to (010). The meth-oxy-methyl group in mol-ecule A is disordered over two sets of sites, with an occupancy ratio of 0.56 (9):0.44 (9).

Exo conformers of N-(pyridin-2-yl)- and N-(pyridin-3-yl)norbornene-5,6-dicarboximide crystals.

Two isomeric pyridine-substituted norbornenedicarboximide derivatives, namely N-(pyridin-2-yl)-exo-norbornene-5,6-dicarboximide, (I), and N-(pyridin-3-yl)-exo-norbornene-5,6-dicarboximide, (II), both C(14)H(12)N(2)O(4), have been crystallized and their structures unequivocally determined by single-crystal X-ray diffraction. The molecules consist of norbornene moieties fused to a dicarboximide ring substituted at the N atom by either pyridin-2-yl or pyridin-3-yl in an anti configuration with respect to the double bond, thus affording exo isomers. In both compounds, the asymmetric unit consists of two independent molecules (Z' = 2). In compound (I), the pyridine rings of the two independent molecules adopt different conformations, i.e. syn and anti, with respect to the methylene bridge. The intermolecular contacts of (I) are dominated by C-H...O interactions. In contrast, in compound (II), the pyridine rings of both molecules have an anti conformation and the two independent molecules are linked by carbonyl-carbonyl interactions, as well as by C-H...O and C-H...N contacts.

Crystal structure of 2-(thio-phen-3-yl)ethyl pyrene-1-carboxyl-ate.

In the title compound, C23H16O2S, the thio-phene group is rotationally disordered into two fractions almost parallel to each other, with occupation factors of 0.523 (7) and 0.477 (7), and subtending dihedral angles of 10.5 (5) and 9.3 (5)°, respectively, to the thio-phene group. The mol-ecules are held together by weak C-H⋯O and C-H⋯π hydrogen bonds, producing a laminar arrangement, which are further connected in a perpendicular fashion by S⋯π contacts [S⋯centroid = 3.539 (8) and 3.497 (8) Å]. In spite of the presence of the entended pyrene group, the structure does not present any parallel π-π stacking inter-actions. The structure was refined as an inversion twin.

Bis(2-amino-4-phenyl-1,3-thia-zol-3-ium) tetra-chlorido-palladate(II).

The title compound, (C9H9N2S)2[PdCl4], consists of two monoprotonated 2-amino-4-phenyl-1,3-thia-zole molecules and one tetra-chlorido-palladate anion. The organic molecules exhibit a dihedral angle between the main rings planes of 31.82 (9)°. In the anion, the Pd(II) atom is located on a crystallographic centre of symmetry with a square-planar geometry. In the crystal, the anions and cations are connected through bifurcated N-H⋯Cl hydrogen bonds, and these inter-actions lead to hydrogen-bonded tapes of cations and anions along [100].

Di-chlorido-(4,4'-di-tert-butyl-2,2'-bi-pyridine-κ(2) N,N')palladium(II) dimethyl sulfoxide monosolvate monohydrate.

The title compound, [PdCl2(C18H24N2)]·(CH3)2SO·H2O, the Pd(II) ion is in a distorted square-planar geometry. The Pd-N bond distances are 2.022 (2) and 2.027 (2) Å, the Pd-Cl bond distances are 2.2880 (7) and 2.2833 (7) Å, and the ligand bite angle is 80.07 (9)°. The dimethyl sulfoxide and water mol-ecules form linear chains along [100] by O-H⋯O and O-H⋯S hydrogen bonds, generating eight- and 12-membered rings. C-H⋯Cl inter-actions link the chains, forming a three-dimensional arrangement. In addition, the 4,4-di-tert-butyl-2,2'-bi-pyridine ligand exhibits π-π stacking inter-actions [centroid-centroid distances = 3.8741 (15) and 3.8353 (15) Å]. The DMSO solvent is disordered and was refined with an occupancy ratio of 0.866 (3):0.134 (3).

Bis(2,3-di-chloro-phen-yl) di-sulfide.

The title compound, C12H6Cl4S2, features an S-S bond [2.0252 (8) Å] that bridges two 2,3-di-chloro-phenyl rings with a C-S-S-C torsion angle of 88.35 (11)°. The benzene rings are normal one to the other with a dihedral angle of 89.83 (11)°. The crystal structure features inter-molecular Cl⋯Cl [3.4763 (11) Å] and π-π stacking inter-actions [centroid-centroid distances = 3.696 (1) and 3.641 (2) Å]. Intra-molecular C-H⋯S inter-actions are also observed.

trans-Chlorido-(4-fluoro-benzene-thiol-ato-κS)bis-(tri-phenyl-phosphane-κP)palladium(II) methanol hemisolvate.

The title compound, [Pd(SC6H4F-p)Cl(PPh3)2]·0.5CH3OH, features a Pd(II) complex with two tri-phenyl-phosphane (PPh3) ligands arranged in a trans conformation, with one chloride and one 4-fluoro-benzene-thiol-ate ligand completing the coordination sphere, giving rise to a slightly distorted square-planar geometry of the Pd(II) ion. The methanol solvent mol-ecule is disordered about an inversion centre with an occupancy of 0.25 for each molecule. In the crystal, weak C-H⋯Cl hydrogen-bonding inter-actions between the complex mol-ecules generate chain frameworks parallel to [010].

4-Methyl-N-(4-methyl-phenyl-sulfon-yl)-N-[4-(4-methyl-phen-yl)-1,3-thia-zol-2-yl]benzene-sulfonamide.

There are two independent mol-ecules in the asymmetric unit of the title compound, C24H22N2O4S3. In each, the sulfonamide N atoms reveal nearly a trigonal-planar geometry with two S atoms of the O=S=O groups and one C atom of the thia-zole ring; the angles around the N atoms are between 117.00 (13) and 123.86 (9)°. The methyl-phenyl-sulfonyl groups are in anti conformations, forming dihedral angles of 78.00 (7)/72.53 (5) and 77.09 (6)/71.50 (7)° with the trigonal S-N-S planes in the two mol-ecules. The thia-zole groups are rotated around the C-N bonds and are almost perpendicular to the S-N-S plane [dihedral angles of 78.00 (7)/72.53 (5) and 77.09 (6)/71.50 (7)°]. In the crystal, pairs of C-H⋯O inter-actions, with the O atoms of the sulfonamide groups as acceptors, link each of the independent mol-ecules into inversion dimers.

trans-Bis(µ-benzene-thiol-ato-κ(2) S:S)bis[chlorido-(tri-phenyl-phosphane-κP)palladium(II)] chloro-form disolvate.

The title compound, [Pd2Cl2(C6H5S)2(C18H15P)2]·2CHCl3, contains a centrosymmetric dinuclear palladium complex with the Pd(II) cation in a slightly distorted square-planar coordination environment. The Pd(II) cations are bridged by the S atoms of two benzene-thiol-ate ligands with different Pd-S distances [2.2970 (11) and 2.3676 (11) Å]. The coordination of the metal atom is completed by a chloride anion [2.3383 (11) Å] and a tri-phenyl-phosphane ligand [2.2787 (11) Å]. Weak C-H⋯Cl inter-actions are present between complex mol-ecules and the CHCl3 solvent mol-ecule. The latter is disordered over two positions in a 0.792 (8):0.208 (8) ratio. The crystal under investigation was found to be twinned by nonmerohedry, with a fraction of 73.4 (1)% for the major twin component.

cis-Bis(O-methyl-dithio-carbonato-κ(2) S,S')bis-(tri-phenyl-phosphane-κP)ruthenium(II).

In the title compound, [Ru(CH3OCS2)2(C18H15P)2], the Ru(II) atom is in a distorted octa-hedral coordination by two xanthate anions (CH3OCS2) and two tri-phenyl-phosphane (PPh3) ligands. Both bidentate xanthate ligands coordinate the Ru(II) atom with two slightly different Ru-S bond lengths but with virtually equal bite angles [71.57 (4) and 71.58 (3)°]. The packing of the complexes is assured by C-H⋯O and C-H⋯π inter-actions.

N-{1,2-Bis(pyridin-3-yl)-2-[(E)-(pyridin-3-yl)methyl-idene-amino]-eth-yl}nicotinamide.

In the title compound, C24H20N6O, the pyridin-3-yl groups on the ethyl-ene fragment are found in a trans conformation with a C(py)-C(e)-C(e)-C(py) (py = pyridine, e = ethylene) torsion angle of 179.2 (3)°. The dihedral angle between the pyridine rings is 3.5 (1)°. In the crystal, N-H⋯N and C-H⋯O=C inter-actions form a layer arrangement parallel to the bc plane. The compound displays disorder of the ethyl-ene fragment over two positions with an occupancy ratio of 0.676 (7) to 0.324 (7) that extends into the amide section of the nicotinamide moiety.

A second monoclinic polymorph of (E)-phen-yl(pyridin-2-yl)methanone oxime.

The title compound, C(12)H(10)N(2)O, a second monoclinic poly-morph of (E)-phen-yl(pyridin-2-yl)methanone oxime crystallizes in the space group P2(1)/n (Z = 4). The previously reported polymorph [Taga et al. (1990 ▶). Acta Cryst. C46, 2241-2243] occurs in the space group C2/c (Z = 8). In the crystal, pairs of bifurcated O-H⋯(N,O) hydrogen bonds link the mol-ecules into inversion dimers. The dimers are linked by C-H⋯π inter-actions, forming a linear arrangement. The dihedral angle between the pyridine and phenyl rings is 67.70 (8)°.

N-Benzyl-2-hy-droxy-ethanaminium cyanurate.

In the cation of the title compound C9H14ON(+)·C3H2O3N3 (-), the benzyl-amine C-N bond subtends a dihedral angle of 78.3 (2)° with the phenyl ring. The cyanurate anion is in the usual keto-form and shows an r.m.s. deviation from planarity of 0.010 Å. In the crystal, the cyanurate anions form N-H⋯O hydrogen-bonded zigzag ribbons along [001]. These ribbons are crosslinked by the organocations via O-H⋯N and N-H⋯O hydrogen bonds, forming bilayers parallel to (010) which are held together along [010] by slipped π-π inter-actions between pairs of cyanurate anions [shortest contact distances C⋯C = 3.479 (2), O⋯N = 3.400 (2); centroid-centroid distance= 4.5946 (9) Å] and between cyanurate and phenyl rings [centroid-centroid distance = 3.7924 (12) Å, ring-ring angle = 11.99 (10)°].

3-[1-(3-Hy-droxy-benz-yl)-1H-benzimid-azol-2-yl]phenol dimethyl sulfoxide monosolvate.

Crystals of the title compound were obtained as a 1:1 dimethyl sulfoxide solvate, C(20)H(16)N(2)O(2)·C(2)H(6)O. The mol-ecular conformation of the organic mol-ecule is similar to that in the previously reported unsolvated structure [Eltayeb et al. (2009 ▶). Acta Cryst. E65, o1374-o1375]. Thus, the dihedral angles formed by the benzimidazole moiety with the two benzene rings are 57.54 (4) and 76.22 (5)°, and the dihedral angle between the benzene rings is 89.23 (5)°. In the crystal, a three-dimensional network features O-H⋯O, O-H⋯N and O-H⋯S hydrogen bonds, as well as C-H⋯O and C-H⋯π inter-actions.

1-Ethenyl-4-[(phenylsulfanyl)methyl]-benzene.

The dihedral angle between the aromatic rings in the title compound, C(15)H(14)S, is 72.38 (7)°. In the crystal, the mol-ecules are connected by C-H⋯π inter-actions.

Bis(methyl xanthato)-κS;κS:S'-(triphenyl-phosphane-κP)palladium(II).

The title compound, [Pd(C(2)H(3)OS(2))(2)(C(18)H(15)P)], features a palladium complex with a triphenyl-phosphane ligand and two xanthate ligands, one of them coordinates in a bidentate and the other in a monodentate fashion, giving rise to a slightly distorted square-planar coordination of the Pd(II) ion. As a result of this difference in the coordination modes, the C-S bond lengths are different, viz. 1.687 (2) and 1.692 (2) Šin the bidentate ligand and 1.723 (2) Šin the monodentate ligand, whereas the non-coordinating S atom has a C-S distance of 1.649 (2) Å. The crystal packing is stabilized by C-H⋯O inter-actions.

Synthesis and in vitro trichomonicidal, giardicidal and amebicidal activity of N-acetamide(sulfonamide)-2-methyl-4-nitro-1H-imidazoles.

Two new series of imidazole derivatives (acetamides: 1-8 and sulfonamides: 9-15) were synthesized using a short synthetic route. Compound 1 as well as the intermediate 16g were characterized by X-ray crystallography. Imidazole derivatives 1-15 were tested in vitro against three unicellular parasites (Giardia intestinalis, Trichomonas vaginalis and Entamoeba histolytica) in comparison with benznidazole (Bzn) and metronidazole. Compound 1 [N-benzyl-2-(2-methyl-4-nitro-1H-imidazol-1-yl)acetamide] was 2 times more active than Bzn against T. vaginalis and G. intestinalis and it was as active as Bzn against E. histolytica. Sulfonamides showed selective toxicity against E. histolytica over the other parasites. Toxicity assay showed that all compounds are non-cytotoxic against MDCK cell line. The results revealed that compounds 1-15 have antiparasitic bioactivity in the micromolar range against the parasites tested, and could be considered as benznidazole bioisosteres.