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El objetivo del estudio fue detectar la presencia de Adenovirus entéricos en muestras de heces de infantes menores de cinco años con enfermedad diarreica aguda (EDA) en la ciudad de Chihuahua, México, en el período de 2004 a 2008 y 2012. Se analizaron un total de 236 muestras de heces diarreicas provenientes de infantes hospitalizados con EDA de la ciudad de Chihuahua, México, con la técnica PCR utilizando los iniciadores Hex1deg y Hex2deg. Se determinaron los serotipos entéricos, en las muestras positivas para Adenovirus, mediante el patrón de las enzimas de restricción HaeIII y Hinfl obtenidos de los productos de PCR. Los resultados obtenidos revelaron que el 24 %, de las 236 muestras analizadas fueron positivas para Adenovirus entéricos, de las cuales 22.3 % correspondieron al serotipo 41 y 1.7 % al serotipo 40, con una mayor cantidad de casos en el período invernal. Con este estudio se detectó la presencia de Adenovirus entérico como agente etiológico de EDA en infantes menores de cinco años en la ciudad de Chihuahua, México, en el periodo 2004-2008, además se encontró la presencia de Adenovirus no entéricos sugiriendo su atención en el futuro como agentes causales de EDA.

Reactions of group 10 transition metals with the ditopic ligand dipicolyldithiocarbamate (DPDTC) were performed. Thus, 1:2 reactions of [Ni(CH3COO)2], [Pd(COD)Cl2] or [Pt(COD)Cl2] with DPDTC produced monomeric complexes of the type [M(κ2-SCS-DPDTC)2, M = Ni (1), Pd (2) or Pt (3)] with the dithiocarbamate ligand (DTC) coordinated in a typical chelate κ2-SCS fashion. Interestingly, the reaction of [NiCl2] with DPDTC, under similar conditions, afforded the organic compound 2-(pyridin-2-ylmethyl)imidazo[1,5-a]pyri-dine-3(2 H)-thione (4) as unique product. In order to prove the ditopic nature of the ligand DPDTC, complex [Pd(κ2-SCS-DPDTC)2] (2) was further reacted with [ZnCl2] in a 1:2 M ratio to yield the trinuclear complex [Cl2Zn(κ2-NN-DPDTC-SCS-κ2)Pd(κ2-SCS-DPDTC-NN-κ2)ZnCl2] (5). The molecular structures of all compounds were determinate by typical analytical techniques including the unequivocal determination of all structures by single crystal X-ray diffraction analysis. As expected, complexes 1–3 are isostructural, and the metal centres exhibiting slightly distorted square-planar geometries. While in 5, the trinuclear nature of the complex in confirmed exhibiting a nice combination of tetrahedral-square planar-tetrahedral geometries for the Zn-Pd-Zn centres respectively. Keywords: Dithiocarbamate, Metal-sulphur complexes, Trinuclear complexes, Ditopic ligands, Hetero-aromatic compound, Di-(2-picolyl)amine cyclization

Chitosan–carboxymethylcellulose/flavylium salt (Ch–CMC/FS) films were obtained at different flavylium salt (FS) concentrations under acidic conditions in order to maintain de benzopyrylium form of the flavylium organic cation. Films were characterized by Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, UV–Vis diffuse reflectance (DRUV) and emission spectroscopy. Thermal properties were also recorded by means of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. FTIR and Raman spectra showed shifting of the carbonyl vibrations after addition of flavylium salt compound. Thermal stability prevailed even after addition of FS as was determined by TGA and DSC analysis. Ch–CMC/FS showed strong absorption in the visible part of the electromagnetic spectrum centred around λ = 450 nm. Luminescence profile after excitation at λ = 450 nm showed an emission centred around λ = 507 nm. FS appears to be chemically stabilized by the interaction with polyelectrolyte chains.

Nanotechnology is focused on the development and application of novel nanomaterials with particular physicochemical properties. Palladium nanoparticles (PdNPs) have been used as antimicrobials, antifungals, and photochemicals and for catalytic activity in dye reduction. In the present investigation, we developed and characterized PdNPs as a carrier of quercetin and initiated a study of its effects in colorectal cancer cells. PdNPs were first functionalized with polyvinylpyrrolidone (PVP) and then coupled to quercetin (PdNPs-PVP-Q). Our results showed that quercetin was efficiently incorporated to PdNPs-PVP, as demonstrated using UV/Vis and FT-IR spectroscopy. Using transmission electron microscopy, we demonstrated a reduction in size from 3–14.47 nm of PdNPs alone to 1.8–7.4 nm of PdNPs-PVP and to 2.12–3.14 of PdNPs-PVP-Q, indicating an increase in superficial area in functionalized PdNPs-Q. Moreover, hydrodynamic size studies using dynamic light scattering showed a reduction in size from 2120.33 nm ± 112.53 with PdNPs alone to 129.96 nm ± 6.23 for PdNPs-PVP-Q, suggesting a major reactivity when quercetin is coupled to nanoparticles. X-ray diffraction assays show that the addition of PVP or quercetin to PdNPs does not influence the crystallinity state. Catalytic activity assays of PdNPs-PVP-Q evidenced the chemical reduction of 4-nitrophenol, methyl orange, and methyl blue, thus confirming an electron acceptor capacity of nanoparticles. Finally, biological activity studies using MTT assays showed a significant inhibition (p &lt, 0.05) of cell proliferation of HCT-15 colorectal cancer cells exposed to PdNPs-PVP-Q in comparison to untreated cells. Moreover, treatment with PdNPs-PVP-Q resulted in the apoptosis activation of HCT-15 cells. In conclusion, here we show for the first time the development of PdNPs-PVP-Q and evidence its biological activities through the inhibition of cell proliferation and apoptosis activation in colorectal cancer cells in vitro.

A series of Pt(II) complexes of the type [Pt(1,10-phenanthroline)(SArF

A series of non-symmetric Pd(II)-POCOP pincer complexes were synthesized in a facile manner from the commercially available starting material 2′,4′-dihydroxyacetophenone. The preparation of the complexes was carried out in a single step affording the corresponding ketone-functionalized pincer complexes. The molecular structures of two complexes were unambiguously determined by single crystal X-ray diffraction analysis. As expected, the metal fragments exhibited a slightly distorted square planar geometry. In addition, the complexes were used as catalysts in Suzuki-Miyaura couplings under microwave irradiation, showing complex 4 to be the best catalyst for a series of para-substituted bromobenzenes.

Pyridylthiother-ligated Pd(II) complexes have been synthesized and efficiently applied in Suzuki-Miyaura couplings using microwave irradiation in DMF and water. The pyridylthioether NS (NS1 and NS2) and pyridyldithiother (SNS) ligands and their corresponding palladium complexes Pd-NS1, Pd-NS2, Pd-SNS were easily synthesized and fully characterized by various analytical techniques. The molecular structures of the ligand SNS and the Pd(II) complexes Pd-NS2, Pd-SNS were unequivocally determined by single crystal X-ray diffraction analysis. From these compounds, complex Pd-SNS exhibits the ligand SNS coordinated in a N,N-bidentated rather than the typical SNS-pincer manner in the solid state, giving place to a seven membered palladacycle whereas in solution it behaves as a typical SNS-pincer complex. This compound was also found to be the most efficient catalyst of the series of complexes in Suzuki-Miyaura couplings with different p-substituted aryl bromides.

A series of Ni(II) and Pt(II) complexes with DTC ligands including a hydrophilic ethanol moiety [N-(R)ethanolamine (R = Me(1), Et(2), iPr(3), Bn (4))] have been prepared and fully characterized. The antitumor activity of the Pt(II) derivatives has been evaluated against different cancer cell lines, showing complex 4-Pt (including N-(benzyl)ethanolamine DTC ligand DTC-4) to be the most active of the series, exhibiting 100% inhibition on glial cells of nervous central system (U251), leukaemia (K562), colon (HCT-15), breast (MCF-7) and lung (SKLU-1). Finally, the Ni(II) derivatives were explored as catalyst in Suzuki-Miyaura couplings, however only decomposition of the complexes was observed with null conversions to biphenyls.

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 NiIIPOCOP pincer complex, [Ni(C29H41N2O8P2)Cl] or [NiCl{C6H2-4-[OCOC6H4-3,5-(NO2)2]-2,6-(OPtBu2)2}]. Both pincer structures exhibit the NiIIatom in a distorted square-planar coordination geometry with the POCOP pincer ligand coordinated in a typical tridentate mannerviathe two P atoms and one arene C atomviaa C—Ni σ bond, giving rise to two five-membered chelate rings. The coordination sphere of the NiIIcentre 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.

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...Owaterand 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.

A series of N-arylfluorinated hydroxylated-Schiff bases were synthesized in a facile and high yield manner. The compounds were fully characterized including the unequivocal determination of the structure of two derivatives (2 and 4) by single crystal X-ray diffraction analysis. Preliminary in vitro antiparasitic activity against an endemic Trypanosoma cruzi strains in Mexico (NINOA) showed these compunds to have better trypanocidal activity compared to the reference drugs Nifurtimox (Nfx) and Benznidazole (Bnz).

The facile and simple synthesis and structural characterization of a Pd(II) complex derived from the ligand N1-(1-(pyridin-2-yl)ethylidene)propane-1,3-diamine (L1) is described. The Pd(II) species [Pd(L1)Cl][BF4] (PdL1) has been fully characterized and its structure unequivocally determined by single crystal X-ray diffraction techniques. The molecular structure of PdL1 shows the ligand L1 coordinated in a κ3-N,N,N-tridentate fashion thus affording a slightly distorted square planar compound. This species was employed as catalyst in Suzuki–Miyaura couplings affording good to excellent yields. Furthermore, in the solid state this compound exhibited extended hydrogen-bond networks.

The synthesis and structural characterization of Ni(II) complexes derived from N1,N4-bis(pyridin-2-ylmethylene)butane-1,4-diamine ( L1 ) and N1,N4-bis(1-(pyridin-2-yl)ethylidene)butane-1,4-diamine ( L2 ) is described. The paramagnetic Ni(II) complexes NiL1 and NiL2 were fully characterized and their structures unequivocally determined by single crystal X-ray diffraction techniques. The molecular structures of NiL1 and NiL2 exhibited the ligands L1 and L2 coordinated in a κ 4 - N,N,N,N -tetradentate fashion. The subtle changes in the ligands defines the ionic o neutral nature of the complexes. Furthermore, in the solid state both complexes exhibit extended hydrogen-bond networks.

A series of group 10 transition metal complexes based on 2-(2-hydroxyphenyl)benzoxazole (HPBO) and 2-(2-hydroxyphenyl)benzothiazole (HPBT) have been prepared. Reactions of nickel or palladium acetates with HPBT and HPBO produce chelate N–O coordinated compounds respectively. Whilst reaction of [K2PtCl4] with HPBT affords organometallic species product of a C–H bond activation of the phenolic moiety at room temperature. The molecular structures of the three complexes were unambiguously determined by means of single crystal X-ray diffraction analyses. The nickel compound [{Ni(κ2-N,O-HPBT)}2(μ2-O-HPBT)2(μ2-OOCCH3)] (1) showing to be binuclear with the nickel ions found in six-coordinated distorted octahedral environments. Conversely, compound [Pd(κ2-N,O-HPBO)2] (2) is a tetracoordinated monomer with the Pd center having a slightly distorted square planar geometry. Similarly, platinacycle [Pt(κ1-N-HPBT)(κ2-N,C-HPBT)Cl] (3) shows the Pt center into a slightly distorted square planar geometry, exhibiting ligand HPBT in two different coordination modes, as single κ1-N coordinated and as κ2-N-C metalated chelate bidentate ligand, completing the coordination sphere with a chloride ligand. The catalytic activity of the palladium complex (2) was evaluated in Suzuki–Miyaura cross couplings, showing good activity.

A series of fluorinated imines of the type [C6H4-1-(OH)-3-(CH NArF)]; ArF C6H4-4-F (1), C6H3-2,3-F2 (2), C6H3-3,5-F2 (3), C6H2-2,4,6-F3 (4), C6H4-3-CF3 (5), C6H3-3,5-(CF3)2 (6), were synthesized and fully characterized including single crystal X-ray diffraction analyses of compounds [C6H4-1-(OH)-3-(CH NC6H4-4-F)] (1), [C6H4-1-(OH)-3-(CH NC6H3-3,5-F2)] (3), [C6H4-1-(OH)-3-(CH NC6H4-3-CF3)] (5). Further analyses of these results allowed the identification of the predominant non-covalent interactions and supramolecular arrangements in the solid state. Exploration of the anti-bacterial activity against both gram-positive and gram-negative bacteria showed those compounds including F or CF3 substituents at the meta positions i.e. [C6H4-1-(OH)-3-(CH NC6H3-3,5-F2)] (3), [C6H4-1-(OH)-3-(CH NC6H4-3-CF3)] (5), [C6H4-1-(OH)-3-(CH NC6H3-3,5-(CF3)2)] (6), to be the best when their activity is compared versus ampicillin.

Two isomeric pyridine-substituted norbornenedicarboximide derivatives, namelyN-(pyridin-2-yl)-exo-norbornene-5,6-dicarboximide, (I), andN-(pyridin-3-yl)-exo-norbornene-5,6-dicarboximide, (II), both C14H12N2O4, 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 ananticonfiguration with respect to the double bond, thus affordingexoisomers. 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. synandanti, 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 ananticonformation and the two independent molecules are linked by carbonyl–carbonyl interactions, as well as by C—H...O and C—H...N contacts.

Four new diorganotin(IV) complexes, R2SnL (L = La: R = Me 1, Ph 2; L = Lb: R = Me 3, and Ph 4), have been synthesized by reaction of hydrazone ONO donors, 5-bromo-2-hydroxybenzaldehyde furan-2-carbohydrazone (H2La) and 2-hydroxynaphthaldehyde furan-2-carbohydrazone (H2Lb) with diorganotin(IV) dichloride in the presence of a base. The compounds have been investigated by elemental analysis and IR, 1H NMR, and 119Sn NMR spectroscopies. Spectroscopic studies show that the hydrazone is a tridentate dianionic ligand, coordinating via the imine nitrogen and phenolic and enolic oxygens. The structures of H2Lb and 3 have also been confirmed by X-ray crystallography. The results show that the structure of 3 is a distorted square pyramid with imine nitrogen in apical position. The in vitro antibacterial activities of ligands and complexes have been evaluated against gram-positive (Bacillus cereus and Staphylococcus aureus) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. H2La and H2Lb show n...

Seven dinuclear macrocyclic palladium(II) dithiocarbamates have been prepared from a homologous series of aliphatic 1,x-diamines (x = 4–10); the objective was to vary systematically the size of the cavity. The resulting complexes were characterized by IR and NMR (1H, 13C) spectroscopy, high-resolution FAB mass spectrometry, and in one case additionally by single-crystal X-ray diffraction analysis. Geometry-optimizations using the B3LYP functional in combination with the def2-SVP basis set were performed for the complete series of 22- to 36-membered macrocycles and showed that these can be divided into two classes. Palladium(II) dithiocarbamates with an even number of methylene spacer groups yield macrocycles of rectangular shape with overall dimensions that vary from 6.0 × 14.5 × 12.7 to 6.0 × 15.7 × 19.9 A3, whereas an odd number generates hexagon-shaped assemblies with overall dimensions in the range 5.0 × 16.3 × 13.0 to 6.0 × 21.1 × 18.7 A3. The computational analysis ruled out the possibility that monomeric structures had formed and indicated that for the creation of strain-free mononuclear macrocyclic structures at least 14 methylene groups are required in the spacer.

Two series of di and trinuclear chlorodiorganotin(IV) complexes derived from bis- and tris-dithiocarbamate ligands have been prepared and structurally characterized. The dinuclear complexes 1–2 of the composition {(R2SnCl)2(bis-dtc)} (1, R = Me; 2, R = nBu) have been obtained from R2SnCl2 (R = Me, nBu) and the triethylammonium salt of N,N′-dibenzyl-1,2-ethylene-bis(dithiocarbamate). The trinuclear complexes 3–9 with the general formula {(R2SnCl)3(tris-dtc)} 3, R = Me, tris-dtc = tris-dtc-Me; 4, R = Me, tris-dtc = tris-dtc-iPr; 5, R = Me, tris-dtc = tris-dtc-Bn; 6, R = nBu, tris-dtc = tris-dtc-Me; 7, R = nBu, tris-dtc = tris-dtc- iPr; 8, R = nBu, tris-dtc = tris-dtc-Bn; 9, R = tBu, tris-dtc = tris-dtc-Me) were prepared from R2SnCl2 (R = Me, nBu, tBu) and the potassium dithiocarbamate salts of (tris[2-(methylamino)ethyl]amine) (tris-dtc-Me), (tris[2-(isopropylamino)ethyl]amine) (=tris-dtc-iPr) and (tris[2-(benzylamino)ethyl]amine) (=tris-dtc-Bn). Compounds 1–9 have been analyzed as far as possible by elemental analysis, FAB+ mass spectrometry, IR and NMR (1H, 13C, 119Sn) spectroscopy, and single-crystal X-ray diffraction analysis. The solid state and solution studies showed that the dtc ligands are coordinated to the tin atoms in the anisobidentate manner. In all cases the metal centers are five-coordinate. The coordination geometry is intermediate between square-pyramidal and trigonal-bipyramidal coordination polyhedra with τ-values in the range of 0.32–0.53. For the members of each series characterized in the solid state by X-ray diffraction analysis, different molecular conformations were found. The crystal structures show the presence of C–H⋯Cl, C–H⋯S, C–H⋯π, S⋯Cl, S⋯S, Cl⋯Sn and S⋯Sn contacts.

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.

The reactivity of N-(2-aminophenyl)-d-glycero-d-gulo-heptonamide (adgha), with the group 12 cations, Zn(II), Cd(II), and Hg(II), was studied in DMSO-d(6) solution. The studied system showed a selective coordination to Hg(II), and the products formed were characterized by (1)H and (13)C NMR in DMSO-d(6) solution and fast atom bombardment (FAB(+)) mass spectra. The expected coordination compounds, [Hg(adgha)](NO(3))(2) and [Hg(adgha)(2)](NO(3))(2), were observed as unstable intermediates that decompose to bis-[2-(d-glycero-d-gulo-hexahydroxyhexyl)-benzimidazole-κN]mercury(II) dinitrate, [Hg(ghbz)(2)](NO(3))(2). The chemical transformation of the complexes was followed by NMR experiments, and the nature of the species formed is sustained by a theoretical study done using DFT methodology. From this study, we propose the structure of the complexes formed in solution, the relative stability of the species formed, and the possible role of the solvent in the observed transformations.

Two new dinuclear diorganotin(IV) dithiocarbamate (dtc) macrocycles, [Me2Sn(dtc)]2 (1) and [nBu2Sn(dtc)]2 (2), have been synthesized from R2SnCl2 (R = Me, nBu) and the bis(dithiocarbamate) derivative of N,N -dibenzylhexamethylene-1,6-diamine. These complexes have been characterized by elemental analysis, FAB mass spectrometry, IR and NMR (H, C, Sn) spectroscopy, as well as single crystal X-ray crystallography. The dtc ligands are coordinated to the tin atoms in the anisobidentate manner, both in solution and the solid state. The metal centers are hexacoordinated and the coordination polyhedron of the tin atoms can be described as bicapped tetrahedron or skew trapezoidal bipyramid. The cavities of the 26-membered macrocycles are hydrophobic with four sulfur atoms directed into the interior and have an inner diameter of approximately 4.1 x 5.6 A. The crystal structure of [Me2Sn(dtc)]2 (1) is stabilized by the presence of two chloroform molecules per asymmetric unit, which participate in intermolecular C-H⋅⋅⋅S, C-H⋅⋅⋅Cl hydrogen bonding and S⋅⋅⋅Cl donor acceptor interactions. On the other hand, the crystal structure of [nBu2Sn(dtc]2 (2) is stabilized additionally by intermolecular C-H⋅⋅⋅π interactions.

In the title compound, C23H16O2S, the thiophene 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 thiophene group. The molecules 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 interactions. The structure was refined as an inversion twin.

The title compound, C12H6Cl4S2, features an S—S bond [2.0252 (8) Å] that bridges two 2,3-dichlorophenyl 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 intermolecular Cl...Cl [3.4763 (11) Å] and π–π stacking interactions [centroid–centroid distances = 3.696 (1) and 3.641 (2) Å]. Intramolecular C—H...S interactions are also observed.