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The molecular and crystal structures of tetrakis (2-propoxy isobutyl isonitrile) copper(I) tetrafluoroborate [Cu(PIBI)4]BF4 were confirmed by powder X-ray diffraction study. The preparation and spectroscopic identification were previously reported. The molecular structure displays the distinctive cation [Cu(PIBI)4]+ and anion [BF4]-. The Cu(I) center of [Cu(PIBI)4]+ unit is surrounded by four 2-propoxy isobutyl isonitrile ligands (each via its isonitrile C atom) asumming a typical tetrahedral geometry. The isontrile C atoms are covalently bonded to Cu center with a mean bond disntance of 1.963(7) Å and C-Cu-C angle of 109.4(4)?. The mean C=N distance (1.138(9) Å) and rather linear of Cu-C=N angles (the largest Cu-C-N angle is 177.8(6)? and the smallest angle is 173.9(0)? give a strong indication that the C=N bond order of 3 in the complex [Cu(PIBI)4]BF4. The counter-ion BF4 - has almost an ideal tetrahedral geometry with an average B-F bond distance of 1.350(4) Å. The crystal packing is achieved by C--H·· ·F short contacts, where each individual [BF4]-anion is involved symmetrically by its four F atoms with four different surrounding [Cu(PIBI)4]+ cations to form supramolecular three-dimensional network. A Hirshfeld surface analysis was carried out to investigate the intermolecular interactions. [ABSTRACT FROM AUTHOR]

Purpose. To synthesize new isoindole-1,3(2H)-dione derivatives by molecular hybridization of gabapentin and pregabalin with phthalic anhydride derivatives and to evaluate their biological activity as promising antioxidant, antimicrobial, and anticancer agents. Method. Molecular hybridization was successfully achieved by two procedures; synthesized compounds were characterized using analytical and spectral methods. The free radical scavenging properties of synthesized compounds were evaluated using the DPPH method. The antibacterial activity of synthesized compounds and parent compounds was evaluated against two microbial Gram-positive and Gram-negative strains by the well diffusion method. Furthermore, we have studied the effect of compounds on proliferation, cell cycle, and cell death in two human cancer cell lines (Caco-2 and HCT-116). Results. Compounds 1, 3, and 4 exhibited a good free radical scavenging effect, and compound 3 is the most effective with IC50 value of 2.525 μmol/mL. All compounds showed antibacterial activity against Escherichia coli and Staphylococcus aureus related to concentration, while parent drugs did not exhibit any antibacterial effect. Compounds 1 and 2 showed a good zone of inhibition against E. coli at micromolar concentrations, and they are more effective than Gentamicin Sulfate. Treatment with the studied compounds suppresses proliferation, arrests progress throughout the cell cycle, and induces apoptosis in Caco-2 and HCT-116 cancer cells. Compound 2 is highly effective against Caco-2 cells and more effective than thalidomide, with IC50 value less than 1 μmol/L. Conclusion. Our results showed that molecular hybridization of gabapentin and pregabalin in the isoindole-1,3(2H)-dione moiety results in promising anticancer and antimicrobial molecules. Results of this preliminary study show that halogenation of the isoindole-1,3(2H)-dione moiety improves antimicrobial and anticancer activity and that tetra-brominated derivatives are comparable to or more effective than related tetra-chlorinated derivatives. [ABSTRACT FROM AUTHOR]

The novel organic–inorganic hybrid salt [(C5H5N)2CH2][Hg2Cl6] was synthesized, isolated as pure white powder and fully characterized by FTIR, multinuclear NMR, UV–Vis spectroscopy and powder-X-ray diffraction studies. The molecular structure displays organic dicaions [(C5H5N)2CH2]2+ and distinctive dimeric anions [Hg2Cl6]2−. Within any indivisual [Hg2Cl6]2− unit, each Hg center is souronded by four Cl atoms (two terminal and two bridging Cl ones) adopting a distorted tetrahedral geometry. The terminal Cl atoms are covalently bonded to Hg with an average bond disntance of 2.32(5) Å and Cl–Hg–Cl angle of 138.14(5)°. In contrast the two bridging Cl ligands to Hg centers have relatively longer mean bond length of 2.51(5) Å and smaller Cl–Hg–Cl bond angle of 93.68(5)°. The edge Cl–Cl are shared by the two roughly tetrahedra to form the dimeric [Hg2Cl6]2−. The relatively large mean Cl–Hg–Cl angle of the terminal Cl atoms (138.14°) and small angle of the bridging ligands (93.68°) indicate a considerable deviation from the ideal tetrahedral geometry. Noteworthy, within each [Hg2Cl6]2− unit, the Hg1...Hg2 distance [3.41(3) Å] is slightly shorter than the sum of the van der Waals radii for Hg(II) indicating a rather weak mercurophilic interaction. The novel organic-inorganic hybrid salt [(C5H5N)2CH2][Hg2Cl6] was synthesized, isolated as pure white powder and fully characterized by FTIR, multinuclear NMR, UV-vis spectroscopy and powder-X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

The design of new organic-inorganic hybrid ionic materials is of interest for various applications, particularly in the areas of crystal engineering, supramolecular chemistry and materials science. The monohalogenated intermediates 1-(2-chloroethyl)pyridinium chloride, C5H5NCH2CH2Cl+·Cl−, (I′), and 1-(2-bromoethyl)pyridinium bromide, C5H5NCH2CH2Br+·Br−, (II′), and the ionic disubstituted products 1,1′-(ethylene-1,2-diyl)dipyridinium dichloride dihydrate, C12H14N22+·2Cl−·2H2O, (I), and 1,1′-(ethylene-1,2-diyl)dipyridinium dibromide, C12H14N22+·2Br−, (II), have been isolated as powders from the reactions of pyridine with the appropriate 1,2-dihaloethanes. The monohalogenated intermediates (I′) and (II′) were characterized by multinuclear NMR spectroscopy, while (I) and (II) were structurally characterized using powder X-ray diffraction. Both (I) and (II) crystallize with half the empirical formula in the asymmetric unit in the triclinic space group P. The organic 1,1′-(ethylene-1,2-diyl)dipyridinium dications, which display approximate C2 h symmetry in both structures, are situated on inversion centres. The components in (I) are linked via intermolecular O-H...Cl, C-H...Cl and C-H...O hydrogen bonds into a three-dimensional framework, while for (II), they are connected via weak intermolecular C-H...Br hydrogen bonds into one-dimensional chains in the [110] direction. The nucleophilic substitution reactions of 1,2-dichloroethane and 1,2-dibromoethane with pyridine have been investigated by ab initio quantum chemical calculations using the 6-31G** basis. In both cases, the reactions occur in two exothermic stages involving consecutive SN2 nucleophilic substitutions. The isolation of the monosubstituted intermediate in each case is strong evidence that the second step is not fast relative to the first. [ABSTRACT FROM AUTHOR]

Marine algae are prolific sources of sulfated polysaccharides, which may explain the low incidence of certain cancers in countries that traditionally consume marine food. Breast cancer is one of the most common types of non-skin cancer in females. In this study, extracted sulfated carrageenan (ESC), predominantly consisting of ι-carrageenan extracted from the red alga Laurencia papillosa, was characterized using Fourier transform infrared spectrometry. The biological effects of the identified extract were investigated and its potential cytotoxic activity was tested against the MDA-MB-231 cancer cell line. The biological biometer of the inhibitory concentration of the polysaccharide-treated MDA-MB-231 cells was determined as 50 μM. Treatment with 50 μM ESC inhibited cell proliferation and promptly induced cell death through nuclear condensation and DNA fragmentation. Characterization of polysaccharide-treated MDA-MB-231 cell death revealed that induction of apoptosis occurred via the activation of the extrinsic apoptotic caspase-8 gene. The apoptotic signaling pathway was regulated through caspase-3, caspase-9, p53, Bax and Bcl-2 genes. These findings suggest that ESC may serve as a potential therapeutic agent to target breast cancer via prompting apoptosis. [ABSTRACT FROM AUTHOR]

The highly insoluble organic-inorganic hybrid ionic compounds N,N′-methylenedipyridinium tetrachloroplatinate(II) [(CHN)CH] · [PtCl] and N,N′-methylenedipyridinium hexachloroplatinate(IV) [(CHN)CH] · [PtCl] were obtained by the treatment of N,N′-methylenedipyridinium dichloride monohydrate [(CHN)CH]Cl · HO with K[PtCl] or (NH)[PtCl], respectively, in an aqueous solution. Both complexes were isolated, purified, characterised by elemental analysis, and their molecular structures were confirmed by powder X-ray diffraction. The crystal structure of both compounds consists of separated discrete dications [(CHN)CH] and anions [PtCl] ( n = 4 or 6). As anticipated, the dications formed a butterfly shape consisting of two pyridine rings bound to the methylene group via their N atoms, while the Pt centre had a square planar geometry in [(CHN)CH] · [PtCl] and an octahedral coordination in [(CHN)CH] · [PtCl]. Interestingly, both crystal structures are stabilised by intermolecular C-H...Cl non-standard hydrogen bonds, π- π ring interactions between two pyridine rings of adjacent dications, and also by Cl- π interactions. [ABSTRACT FROM AUTHOR]

In order to explore the potential propensity of the 1,1′-methylenedipyridinium dication to form organic-inorganic hybrid ionic compounds by reaction with the appropriate halide metal salt, the organic-inorganic hybrid salts 1,1′-methylenedipyridinium tetrachloridocuprate(II), (C11H12N2)[CuCl4], (I), and 1,1′-methylenedipyridinium bis[tetrachloridoaurate(III)], (C11H12N2)[AuCl4]2, (II), were obtained by treatment of 1,1′-methylenedipyridinium dichloride with CuCl2 and Na[AuCl4], respectively. Both hybrid salts were isolated as pure compounds, fully characterized by multinuclear NMR spectroscopy and their molecular structures confirmed by powder X-ray diffraction studies. The crystal structures consist of discrete 1,1′-methylenedipyridinium dications and [CuCl4]2− and [AuCl4]− anions for (I) and (II), respectively. As expected, the dications form a butterfly shape; the CuII centre of [CuCl4]2− has a distorted tetrahedral configuration and the AuIII centre of [AuCl4]− shows a square-planar coordination. The ionic species of (I) and the dication of (II) each have twofold axial symmetry, while the two [AuCl4]− anions are located on a mirror-plane site. Both crystal structures are stabilized by intermolecular C-H...Cl hydrogen bonds and also by Cl...π interactions. It is noteworthy that, while the average intermolecular centroid-centroid pyridinium ring distance in (I) is 3.643 (8) Å, giving strong evidence for noncovalent π-π ring interactions, for (II), the shortest centroid-centroid distance between pyridinium rings of 5.502 (9) Å is too long for any significant π-π ring interactions, which might be due to the bulk of the two [AuCl4]− anions. [ABSTRACT FROM AUTHOR]

Treatment of N,N′-methylenedipyridinium dichloride [CHN-CH-NCH]Cl with MCl (M = Zn or Cd) in aqueous solution gives the organic-inorganic hybrid ionic compounds [CHN-CH-NCH] · [MCl]. Both complex salts were fully characterised by multinuclear NMR spectroscopy, elemental analysis, and their molecular structures confirmed by powder X-ray diffraction studies. The most striking feature in both solid state structures was the presence of the C...Cl-M short contacts between the organic [CHN-CH-NCH] dication and inorganic [MCl] anion, which led to different crystal packing. For [CHN-CH-NCH]·[ZnCl], the C...Cl-Zn interactions led to the alternating arrangement of [CHN-CH-NCH][ZnCl] to form 1-D chains in the direction [010], and each individual chain had a two-fold rotational axis along the b axis, while for [CHN-CH-NCH] · [CdCl] the C...Cl-Cd associations gave 2-D network. In both solid state structures, the presence of Cl-ring centroid distances gave a strong indication of some form of Cl- π interactions. [ABSTRACT FROM AUTHOR]

The article describes the structures of 2-(benzoylsulfanyl)acetic acid and 2,5-dioxopyrrolidin-1-yl 2-(benzoyl-sulfanyl)acetate determined via powder X-ray diffraction. The crystal packing of the first compound consists of a weak carbon (C) -- hydrogen (H) ⋯ oxygen (O) hydrogen bond between an aromatic C--H group and a carboxylic acid O atom to form a 2-dimensional network. The second compound consists of weak C--H⋯O hydrogen bonds between the H atoms of the methylene groups and carbonyl O atoms to form a 3-dimensional network.

The article reports on the synthesis and crystallization of meso-hexamethyl propylene amine oxime through powder X-ray diffraction. The direct-space method with the parallel tempering algorithm was used in crystallization. Intermolecular hydrogen-bonding interactions between the two O-H oxime groups dominate the crystal packing of the two phases. The geometry of hydrogen bond and selected geometric parameters are presented in tables.

The article presents a powder study of poly[µ2-2,2-dimethylpropane-1,3-diyl diisocyanide)-µ2-iodido-silver(I)]. In this study, the researchers showed that the bidentate ligand forms similar polymeric structures on treatment with AgX, regardless of the nature of the counter-ion X-. They also presented a strong tendency to form polymeric complexes rather than dimeric or trimeric ones.

2-Methyl-2-propoxypropyl isocyanide [CNCH2C(OPr)(CH3)2] and its Cu(I) tetrafluoroborate complex [Cu{CNCH2C(OPr)(CH3)2}4]BF4 were prepared in good yields and purities. Both compounds were fully characterized by IR and NMR spectroscopy. [ABSTRACT FROM AUTHOR]