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Two new Hg(II) and Cd(II) one-dimensional coordination polymers have been constructed from metal iodide and a N, N′-Bis-pyridin-4-ylmethylene-naphthalene-1,5-diamine ligand using conventional methods. The effects of the ligand geometry and the coordination modes of iodide on the structures of the coordination polymers have been discussed in detail. In order to clarify the effect of experimental conditions on the morphology and size of [Cd(L)I2]n (1) and [Hg(L)I2]n particles, we have systematically investigated the influence of concentration and sonication power on the size of the resulting products for the aim of realizing controllable synthesis. The results indicated that the concentration and sonication power directly influenced the final size of nanostructures of these coordination polymers. The prepared nanocrystals of these two coordination polymers were analyzed using scanning electron microscopy, infrared spectroscopy and X-ray powder diffraction.

The compound (E)-N-(2,4-difluorophenyl)-1-(4-pyridinyl)methanimine monohydrate (1) was synthesized, characterized spectroscopically and by X-ray crystallography. 1 crystallizes in the non-centrosymmetric C2 space group with Z=4 (two organic molecules, 1a and 1b, and two water molecules). The crystal structure presents O–H···N, non-classical C–H···X hydrogen-bonds, and π–π stacking interactions. Hirshfeld Surface studies confirmed these interactions. The main intermolecular interactions are the π–π between the pyridine and the fluorinated ring of molecules stacking in columns (1a with 1a and 1b with 1b) and the O–H···N H-bonds. The imine acts as a H-bond-donor to the water molecules and a H-bond-acceptor of the water molecule's hydrogen atoms. The energy frameworks show significant interactions between molecules that are not easy to identify by geometric parameters, indicating the convenience of energy calculations to understand crystal structures better.

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 structural modification of natural products has shown to be a remarkable tool in the generation of novel bioactive molecules. Herein, the synthesis, structural analysis and anticancer activity of the novel triterpenoid thiazole 3 is reported. The synthesis was carried out through the bromination of ochraceolide A (1) and the subsequent heterocyclic condensation with thiourea (overall yield of 80%). The bromination reaction of 1 led to obtain a diastereomeric mixture of 2α- and 2β-bromo ochraceolide A in a ratio of 6:4 (2a and 2b, respectively). Compound 3 was fully characterized by 1D and 2D NMR spectroscopy, FT-IR, HR-MS and single-crystal X-ray diffraction analysis. The triterpenoid thiazole crystallized as an ethyl acetate hemisolvate in the orthorhombic space group P212121 with one molecule of 3 in the asymmetric unit. In the crystal, the molecules interact mainly through N–H⋯N and N–H⋯S hydrogen bonds via a R22 (8) synthon. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (69.5%), H⋯O/O⋯H (16.4%), H⋯C/C⋯H (5.5%), H⋯S/S⋯H (4.6%) and H⋯N/N⋯H (3.5%) interactions. The cytotoxicity and antiproliferative activity of 1, the diastereomeric mixture of 2-bromo ochraceolide A (2a and 2b) and 3 against three cancer cell lines (MCF-7, MDA-MB-231 and SiHa) were investigated. The novel thiazole derivative 3 exhibited significant cytotoxicity and antiproliferative activity against the three cancer cells.

Copper(II) complexes of three chiral enantiomeric pairs of o-hydroxy Schiff bases derived from (R)-(−)-secbutylamine and (S)-(+)-secbutylamine, were prepared and characterized by i.r., electronic, cd, epr and mass spectra. Some X-ray crystal structures were obtained. The X-ray study of five complexes shows that the geometry around the metal atom is pseudotetrahedral. Additionally, epr studies of all these complexes in dmf solution at 77 K suggest that their geometry in liquid phase is slightly different to that observed in solid state by X-ray crystallography. Even though, cd spectra only show charge transfer absorptions, the data confirm the enantiomeric pair character of the obtained complexes.

The complex [RuCl 2 (CO)(DMF)(PPh 3 ) 2 ], was easily synthesized in high yield from [RuCl 2 (PPh 3 ) 3 ] and DMF as source of CO. The carbonylated specie has been characterized by X-ray structural analysis.

In solution, allyl palladium homobimetallic complexes bridged by fluorinated benzenethiolates, [{Pd(μ-SR)(η3-C3H5)}2] where R=C6F5, 1; C6HF4-4, 2; C6H4F-2, 3; C6H4F-3, 4 and C6H4F-4, 5, are found as a mixture of syn/anti and cis/trans isomers. The variable temperature 1H and 19F NMR study of these compounds show that the four isomers undergo interconversion through two probable mechanisms, allyl rotation assisted by the solvent and inversion of the configuration at the sulphur atoms. The X-ray crystal structure determination of [{Pd(μ-SC6F5)(η3-C3H5)}2] and [{Pd(μ-S C6HF4-4)(η3-C3H5)}2] shown both complexes to be bimetallic with the metal centres found in a slightly distorted square planar environments.

The title ethylene ketal 1, C23H23F2NO2, has a tricyclic azaadamantane cage with aryl rings (4-fluorophenyl) substituted at the 2 and 9 positions. Rings A (C11–C16) and B (C17–C22) are attached to atoms C2 and C9 in axial and equatorial positions, respectively; and the presence of the five-membered 1,3-dioxolane ring attached to atom C4. The structural analysis of the title was carried out by experimental (single crystal X-ray diffraction and NMR) and confirmed by theoretical calculations (ab initio RHF, DFT and NMR-DFT-GIAO).

The synthesis of dimethyl {2-[3-(4-nitrophenyl)-1 H -pyrazol-5-yl]ethyl}malonate monohydrate 1 , C 16 H 17 N 3 O 6 ·H 2 O was performed and the molecular structure has been studied by using NMR, single crystal X-ray diffraction and ab initio calculations. The title compound presents a pyrazole ring (N1 to C5), a phenyl ring (C1″ to C6″) attached to C3 and the ethylene dimethyl malonate frame (C1′ to C7′) attached to C5. The torsion angle defined by N2C3C1″C2″ (−12.26°) showed that pyrazole and phenyl rings are not in the same plane. Monohydration in ( 1 ) is present in the structure by a NH⋯OH 2 hydrogen bonding, with a bond length of 1.782 A. Experimental and theoretical evidences indicated the preference of the 3-tautomer over the corresponding 5-tautomer in the titled pyrazole.

N-2-(3-picolyl)-N′-phenylthiourea, 3PicTuPh, monoclinic, P21/n, a=7.617(2) b=7.197(5), c=22.889(5) A, β=94.63(4)°, V=1250.7(1) A3 and Z=4; N-2-(4-picolyl)-N′-phenylthiourea, 4PicTuPh, triclinic, P-1, a=7.3960(5), b=7.9660(12), c=21.600(3) A, α=86.401(4), β=84.899(8), γ=77.769(8)°, V=1237.5(3) A3 and Z=4; N-2-(5-picolyl)-N′-phenylthiourea, 5PicTuPh, monoclinic, P21/c, a=14.201(1), b=4.905(3), c=17.689(3) A, β=91.38(1)°, V=1231.8(7) A3 and Z=4; N-2-(6-picolyl)-N′-phenylthiourea, 6PicTuPh, monoclinic, C2/c2, a=14.713(1), b=9.367(1), c=18.227(1) A, β=92.88(1)°, V=2515.5(1) A3 and Z=8 and N-2-(4,6-lutidyl)-N′-phenylthiourea, 4,6LutTuPh, monoclinic, C2/c, a=11.107(2), b=11.793(2), c=20.084(4) A, β=96.10(3)°, V=2616(1) A3 and Z=8. Intramolecular hydrogen bonding between N′H and the pyridyl nitrogen and intermolecular hydrogen bonding involving the thione sulfur are affected by substitution of the pyridine ring, as is the planarity of the molecule. 1H NMR studies in CDCl3 show the NH′ hydrogen resonance considerably downfield from other resonances in the spectrum for each thiourea.

Three copper(II) complexes derived from bulky ortho-hydroxy Schiff base ligands, (1)–(3), were synthesized and characterized by chemical analysis, UV–Vis, IR, μeff and mass spectrometry. The solid state structures of compounds (1)–(3) were determined. The solid state X-ray diffraction studies of these compounds show that the geometry is intermediate between square planar and tetrahedral. Moreover, EPR studies in DMF solution at 77 K suggest that the geometry of these complexes in solution is different from that observed in the solid state by X-ray crystallography. Furthermore, cyclic voltammetry studies performed for (1)–(3), indicate a dependence of the cathodic potentials upon conformational and electronic effects.

The crystal structure of 2,4,6,8-tetra-t-Bu-phenothiazine 0.5C6H6 (Pnma space group, a=11.685, b=25.593, c=10.339) shows short intermolecular t-Bu(CH3)⋯Ph and CH3⋯CH3 contacts which allow the formation of well defined channels along the a direction. These channels host one benzene molecule for each pair of phenothiazine molecules. AM1 molecular orbital calculations suggest that there is a strong coupling of the t-Bu groups rotations and the folding of the ring and this in turn makes the phenothiazine skeleton to be less folded than expected from the presence of four electron donating substituents.

N -(2-pyridylethyl)- N ′-phenylthiourea, triclinic, P-1, a=8.616(1) A , b=9.663(1) A , c=9.761(1) A , α =102.05(1)°, β =102.36(1)°, and γ =116.17(1)°, V=668.5(1) A 3 , Z =2, μ=2.022 mm −1 , N -(2-pyridylethyl)- N ′- p -tolylthiourea, triclinic, P-1, a=8.804(3) A , b=9.951(2) A , c=10.255(2) A , α =115.03(2)°, β =105.93(2)°, γ =104.04(2)°, V=713.43(1) A 3 , Z =2, μ=2.173 mm −1 , N -(2-pyridyl-ethyl)- N ′- p -bromophenylthiourea, triclinic, P-1, a=9.536(1) A , b=9.809(1) A , c=10.042(2) A , α =115.88(1)°, β =96.80(1)°, and γ =110.44(1)°, V=750.0(6) A 3 , Z =2, μ=28.73 mm −1 , N -(2-pyridyl-ethyl)- N ′- p -nitrophenylthiourea, triclinic, P-1, a=8.046(2) A , b=8.602(3) A , c=10.938(3) A , α =80.74(3)°, β =89.77(2)°, γ =77.00(3)°, V=727.6(6) A 3 , Z =2, μ=2.325 mm −1 and N -(2-pyridylethyl)- N ′- p -methoxyphenylthiourea, monoclinic, P2 1 /n, a=11.526(2) A , b=9.723(2) A , c=13.460(2) A , β =100.49(2)°, V=1483.3(2) A 3 , Z =4, μ=1.929 mm −1 . All five molecules possess an intramolecular hydrogen bond between NH and the pyridyl nitrogen, as well as intermolecular hydrogen bonding between N′H and a thione sulfur of a second molecule to form centrosymmetric dimers. Solution 1 H NMR studies (CDCl 3 ) show the N′H resonance downfield for each thiourea and its shift, as well as that of NH, is affected by substituents on the phenyl ring.

1-phenyl-1,2-propanedione bis{N(4)-methyl- and {N(4)-ethylthiosemicarbazone}, H2Pm4M and H2Pm4E, respectively, have been prepared, studied spectroscopically (1H NMR, ultraviolet and infrared) and their crystal structures solved. Intermoiety hydrogen bonding does not occur in H2Pm4M and H2Pm4E, in contrast to the analogous bis{N(4)-thiosemicarbazones} prepared from 1-phenylglyoxal. The two thiosemicarbazone moieties are on the opposite side of the carbon–carbon backbone, but the N(4)Hs intramolecularly hydrogen bond to the imine nitrogen for each moiety.

N-(2-pyridyl)-N′- o -tolylthiourea, monoclinic, P2 1 /c, a =5.127(1), b =19.854(2), c=12.077(2) A , β =94.96(1)°, V=1224.7(2) A 3 , Z =4, μ=2.177 mm −1 , N-(2-pyridyl)-N′-m-tolylthiourea, triclinic, P−1, a =9.811(2), b =9.887(4), c=13.595(3) A , α =74.91(3), β =83.58(2), γ =76.27(2)°, V=1235.(7) A , Z =4, m=2.469 mm −1 and N-(2-pyridyl)-N′-p-tolylthiourea, triclinic,P−1, a =9.935(2), b =11.488(2), c=12.569(2) A , α =63.91(2), β =88.60(2), γ =75.04(2)°, V=1238.1(2) A 3 , Z =4, μ=2.154 mm −1 all have an intramolecular hydrogen bond between N′H and the pyridyl nitrogen, as well as intermolecular hydrogen bonding between NH and a thione sulfur of a second molecule to form centrosymmetric dimers. Solution 1 H NMR studies (CDCI 3 ) show the N′H resonance considerably downfield for each thiourea and its position, as well as that of NH, are affected by substituents on the phenyl ring.