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The present study demonstrated the synthesis of porous coordination polymers (CPs), which built from piperazine (P) and benzen-1,2,4,5 tetracarboxylic acid (BTCA) with different metal ions, copper and cadmium. CPs were magnetized with iron oxide nanoparticles and were successfully synthesized BTCA-P-Cu-MCP and BTCA-P-Cd-MCP. The influence of framework metal ions on the adsorption behaviour of cationic methylene blue (MB) and anionic Chicago Sky Blue (CSB) textile dyes towards both magnetized CPs was investigated. Fourier transform infrared, X-ray diffraction, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy, CHN, and Brunauer–Emmett–Teller analysis were used to characterize the synthesized adsorbents. The surface area and the pore size of BTCA-P-Cu-MCP and BTCA-P-Cd-MCP were 10.68 and 5.45 m2 g−1, 174.00 and 291.97 Å, respectively. BTCA-P-Cd-MCP more selective towards anionic CSB than cationic MB, while BTCA-P-Cu-MCP has the same selectivity for both dyes. The effect of adsorbent dosage, pH and contact time on the adsorption experiment was investigated. Adsorption isotherm, kinetic, and thermodynamic studies were applied for evaluation of the adsorption process. BTCA-P-Cu-MCP exhibited higher adsorption capacity of 130.0 and 64.6 mg g−1compared to BTCA-P-Cd-MCP with adsorption capacity of 29.7 and 3.6 mg g−1 for CSB and MB adsorption, respectively. The adsorption kinetic of both dyes followed pseudo-second-order reaction kinetic. The adsorption of dyes on MCPs was spontaneous, feasible, and exothermic, as shown in the thermodynamic results study. Most significantly, the results prove the influence of framework metal ion (Cu2+ and Cd2+) on the adsorbent surface charge and properties that critically affects the dye removal properties including capacity and adsorption rate. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of two homoleptic morpholine-derived dithiocarbamates of zinc, binuclear {Zn[S2CN(CH2CH2)2O)2]2}2 (1), and cadmium, one-dimensional coordination polymer {Cd[S2CN(CH2CH2)2O)2]2}2 (2), are described. In 1, a centrosymmetric binuclear molecule is found as there are equal numbers of chelating and bidentate bridging dithiocarbamate ligands; weak transannular Zn···S interactions are found within the resultant eight-membered {···SCSZn}2 ring which has the form of a chair. The resultant 4+1 S5 donor set is highly distorted with the geometry tending towards a square-pyramid. By contrast, a square-planar geometry is found in centrosymmetric 2 defined by symmetrically chelating dithiocarbamate ligands. The presence of Cd···S secondary bonding in the crystal of 2 leads to a distorted 4+2 S6 octahedron and a linear coordination polymer, which is unprecedented in the structural chemistry of cadmium dithiocarbamates. The analyses of the Hirshfeld surfaces for 1 and 2 show the dominance of H···H, S···H/H···S and O···H/H···O contacts to the surface, i.e. contributing around 90 and 80%, respectively. [ABSTRACT FROM AUTHOR]

Background. Peperomia belongs to the family of Piperaceae. It has different uses in folk medicine and contains rare compounds that have led to increased interest in this genus. Peperomia blanda (Jacq.) Kunth is used as an injury disinfectant by Yemeni people. In addition, the majority of Yemen's population still depend on the traditional remedy for serious diseases such as cancer, inflammation and infection. Currently, there is a deficiency of scientific evidence with regards to the medicinal plants from Yemen. Therefore, this study was performed to assess the chemical profile and in vitro antioxidant and cytotoxic activities of P. blanda. Methods. Chemical profiling of P. blanda was carried out using gas chromatography mass spectrometry (GCMS) followed by isolation of bioactive compounds by column chromatography. DPPH· and FRAP assays were used to evaluate antioxidant activity and the MTT assay was performed to estimate the cytotoxicity activity against three cancer cell lines, namely MCF-7, HL-60 and WEHI-3, and three normal cell lines, MCF10A, WRL-68 and HDFa. Results. X-ray crystallographic data for peperomin A is reported for the first time here and N,N0-diphenethyloxamide was isolated for the first time from Peperomia blanda. Methanol and dichloromethane extracts showed high radical scavenging activity with an IC50 of 36.81 ± 0.09 µg/mL, followed by the dichloromethane extract at 61.78 ± 0.02 µg/mL, whereas the weak ferric reducing activity of P. blanda extracts ranging from 162.2 ± 0.80 to 381.5 ± 1.31 µg/mL were recorded. In addition, petroleum ether crude extract exhibited the highest cytotoxic activity against all the tested cancer cell lines with IC50 values of 9.54 ± 0.30, 4.30 ± 0.90 and 5.39 ± 0.34 µg/mL, respectively. Peperomin A and the isolated mixture of phytosterol (stigmasterol and β-sitosterol) exhibited cytotoxic activity against MCF-7 and WE-HI cell lines with an IC50 of (5.58 ± 0.47, 4.62 ± 0.03 µg/mL) and (8.94 ± 0.05, 9.84 ± 0.61 µg/mL), respectively, compared to a standard drug, taxol, that has IC50 values of 3.56 ± 0.34 and 1.90 ± 0.9 µg/mL, respectively. Conclusion. The activities of P. blanda extracts and isolated compounds recorded in this study underlines the potential that makes this plant a valuable source for further study on anticancer and antioxidant activities. [ABSTRACT FROM AUTHOR]

The full molecule of the binuclear title compound, [Cd2Cl2(C6H8O4)(C6H8N2)2- (H2O)2], is generated by the application of a centre of inversion located at the middle of the central CH2--CH2 bond of the adipate dianion; the latter chelates a CdII atom at each end. Along with two carboxylate-O atoms, the CdII ion is coordinated by the two N atoms of the chelating benzene-1,2-diamine ligand, a Cl- anion and an aqua ligand to define a distorted octahedral CdClN2O3 coordination geometry with the monodentate ligands being mutually cis. The disparity in the Cd--N bond lengths is related to the relative trans effect exerted by the Cd--O bonds formed by the carboxylate-O and aqua-O atoms. The packing features water-O--H ... O(carboxylate) and benzene-1,2-diamine-N--H ... Cl hydrogen bonds, leading to layers that stack along the a-axis direction. The lack of directional interactions between the layers is confirmed by a Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

The crystallographic structures of 12 palladium xanthates, Pd(S2COR)2 (R = alkyl) show a uniform adoption of square-planar PdS4 geometries. Supramolecular aggregation in 1 (R = Me), 2 (Et) and 3 (n-Pr) is based on secondary Pd…S interactions, which are “turned off” when the bulk of R increases. In 4 (i-Pr), C–H…S hydrogen bonding is present. In each of 2–4, C–H…π(PdS2C) interactions are incorporated within the architecture, stabilised by Pd…S secondary- or C–H…S hydrogen-bonding. In 5–12 (R = n-Bu, i-Bu, n-Pent, i-Pent, neoPent, n-Hex, i-Hex, neoHex), varying numbers of stand-alone C–H…π(PdS2C) interactions involving different hydrogen donors uniformly stabilise supramolecular chains in their crystal structures. In order to determine the relative importance of the various intermolecular interactions and packing effects, a computational study using dispersion-corrected density-functional theory was performed on 3 (R = n-Pr). The results showed that the most significant contributors to the stability of the crystal structure are Pd…S interactions followed closely by C–H…π(PdS2C) interactions. Two non-specific hydrophobic interactions also contribute to the overall packing to a lesser extent. The utility of Pd(S2COR)2 to function as synthetic precursors for PdS nanoparticles and thin films was also investigated. Aerosol-assisted-CVD on representative examples generated PdS films with either matted, needle-like or granular morphologies depending on temperature and substrate. Solvothermal (ethylene glycol) decomposition generated sulphur-rich PdS nanoparticles with diameters 120 nm (7 and 10)–400 nm (8). When dodecanethiol was employed as a capping agent, PdS1.75 nanoparticles ＜10 nm were generated from 1. [ABSTRACT FROM AUTHOR]

Crystallization of Cd[S2CN(iPr)CH2CH2OH]2 from ethanol yields the coordination polymer [{Cd[S2CN(iPr) CH2CH2OH]2}·EtOH]∞(1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S2CN(iPr)CH2CH2OH]2}2·2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ2k2-tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ2k2-tridentate as for 1 but the other two being k2-chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S2CN(iPr) CH2CH2OH]2}3·MeCN] and binuclear {Cd[S2CN(iPr)CH2CH 2 OH] 2}2·2H2O·2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S2CN(iPr)CH2CH2OH]2}2:2[3-(propan- 2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPr NH2(CH2CH2OH)] 4 [SO4] 2{Cd[S2CN(iPr)CH2CH2OH]2}2 (4) and the salt [iPrNH2(CH2CH2OH)]{Cd[S2CN(iPr)CH2CH2OH] 3} (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S2CN(iPr)CH2CH2OH]2}2 SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title salt, C14H16N4O22+.2C9H5O6-, comprises half a dication, being located about a centre of inversion, and one anion, in a general position. The central C4N2O2 group of atoms in the dication are almost planar (r.m.s. deviation = 0.009 Å), and the carbonyl groups lie in an anti disposition to enable the formation of intramolecular amide-N--H···O(carbonyl) hydrogen bonds. To a first approximation, the pyridinium and amide N atoms lie to the same side of the molecule [Npy--C--C--Namide torsion angle = 34.8 (2)°], and the anti pyridinium rings are approximately perpendicular to the central part of the molecule [dihedral angle = 68.21 (8)°]. In the anion, one carboxylate group is almost coplanar with the ring to which it is connected [Cben--Cben--Cq--O torsion angle = 2.0 (3)°], whereas the other carboxylate and carboxylic acid groups are twisted out of the plane [torsion angles = 16.4 (3) and 15.3 (3)°, respectively]. In the crystal, anions assemble into layers parallel to (104) via hydroxy-O--H···O(carbonyl) and charge-assisted hydroxy-O -- H···O(carboxylate) hydrogen bonds. The dications are linked into supramolecular tapes by amide-N--H···O(amide) hydrogen bonds, and thread through the voids in the anionic layers, being connected by charge-assisted pyridinium-N--O(carboxylate) hydrogen bonds, so that a three-dimensional architecture ensues. An analysis of the Hirshfeld surface points to the importance of O--H···O hydrogen bonding in the crystal structure. [ABSTRACT FROM AUTHOR]

The common feature of the title compounds, [Zn(C5H10NO2S2)2(C10H8N2)]-- 2H2O, (I), and [Zn(C6H12NOS2)2(C10H8N2)], (II), is the location of the Znn atoms on a twofold rotation axis. Further, each ZnII atom is chelated by two symmetry-equivalent and symmetrically coordinating dithiocarbamate ligands and a 2,20-bipyridine ligand. The resulting N2S4 coordination geometry is based on a highly distorted octahedron in each case. In the molecular packing of (I), supramolecular ladders mediated by O--H···O hydrogen bonding are found whereby the uprights are defined by {···HO(water)···HO(hydroxy)···}n chains parallel to the a axis and with the rungs defined by 'Zn[S2CN(CH2CH2)2]2'. The water molecules connect the ladders into a supramolecular layer parallel to the ab plane via water-O--H···S and pyridyl-C--H···O(water) interactions, with the connections between layers being of the type pyridyl-C--H···S. In (II), supramolecular layers parallel to the ab plane are sustained by hydroxy-O -- H···S hydrogen bonds with connections between layers being of the type pyridyl-C--H···S. [ABSTRACT FROM AUTHOR]

The title compound, [Cd(C6H12NOS2)2(C4H10N2)], features a distorted squarepyramidal coordination geometry about the central Cdn atom. The dithiocarbamate ligands are chelating, forming similar Cd--S bond lengths and define the approximate basal plane. One of the N atoms of the piperazine molecule, which adopts a chair conformation, occupies the apical site. In the crystal, supramolecular layers propagating in the ac plane are formed via hydroxy-O -- H···O(hydroxy), hydroxy-O--H···N(terminal-piperazine) and coordinatedpiperazine- N--H···O(hydroxy) hydrogen bonds; the layers also feature methine-C--H···S interactions and S···S [3.3714 (10)Å] short contacts. The layers stack along the b-axis direction with very weak terminal-piperazine-N -- H···O(hydroxy) interactions between them. An evaluation of the Hirshfeld surfaces confirms the importance of intermolecular interactions involving oxygen and sulfur atoms. [ABSTRACT FROM AUTHOR]

The title 2:1 co-crystal, 2C7H5NO4⋅C14H14N4O2, in which the complete diamide molecule is generated by crystallographic inversion symmetry, features a three-molecule aggregate sustained by hydroxyl-O--H⋯N(pyridyl) hydrogen bonds. The p-nitrobenzoic acid molecule is non-planar, exhibiting twists of both the carboxylic acid and nitro groups, which form dihedral angles of 10.16 (9) and 4.24 (4)°, respectively, with the benzene ring. The diamide molecule has a conformation approximating to a Z shape, with the pyridyl rings lying to either side of the central, almost planar diamide residue (r.m.s. deviation of the eight atoms being 0.025 Å), and forming dihedral angles of 77.22 (6)° with it. In the crystal, three-molecule aggregates are linked into a linear supramolecular ladder sustained by amide-N--H⋯O(nitro) hydrogen bonds and orientated along [104]. The ladders are connected into a double layer via pyridyl- and benzene-C--H⋯O(amide) interactions, which, in turn, are connected into a three-dimensional architecture via it-it stacking interactions between pyridyl and benzene rings [inter-centroid distance = 3.6947 (8) Å]. An evaluation of the Hirshfeld surfaces confirm the importance of intermolecular interactions involving oxygen atoms as well as the it-it interactions. [ABSTRACT FROM AUTHOR]

Eleven compounds: goniomicin A (1), goniomicin B (2), goniomicin C (3), goniomicin D (4), tapisoidin (5), goniothalamin (6), 9-deoxygoniopypyrone (7), pterodondiol (8), liriodenine (9), benzamide (10) and cinnamic acid (11), were isolated from the stem bark of Goniothalamus tapisoides. All compounds were identified by spectroscopic analysis and, for known compounds, by comparison with published data. Goniothalamin (6) exhibited mild cytotoxic activity towards a colon cancer cell line (HT-29), with an IC50 value of 64.17 ± 5.60 μM. Goniomicin B (2) give the highest antioxidant activity in the DPPH assay among all compounds tested, with an IC50 of 0.207 μM. [ABSTRACT FROM AUTHOR]

Evidence for C-H...π(CuCl...HNCS) interactions, i.e. C-H...π(quasichelate ring) where a six-membered quasi-chelate ring is closed by an N-H...Cl hydrogen bond, is presented based on crystal structure analyses of (Ph3P)2Cu[ROC(=S)N(H)Ph]Cl. Similar intramolecular interactions are identified in related literature structures. Calculations suggest that the energy of attraction provided by such interactions approximates 3.5 kcal mol-1. [ABSTRACT FROM AUTHOR]

C10H22BiClN2O3S4, orthorhombic, Pca21 (no. 29), a = 8.1121(4) Å, b = 10.8634(5) Å, c = 20.7900(9) Å, V = 1832.1 ų, Z = 4, Rgt(F) = 0.0278, wRref(F²) = 0.0574, T = 100 K. [ABSTRACT FROM AUTHOR]

C26H37ClN2S4Sn, monoclinic, C2/c (no. 15), a = 29.2206(11) Å, b = 10.6749(4) Å, c = 19.6877(7) Å, β = 104.411(4)°, V = 5947.9 ų, Z = 8, Rgt(F) = 0.0235, wRref(F²) = 0.0545, T = 100 K. [ABSTRACT FROM AUTHOR]

The article discusses the crystal structure of 3-(propan-2-yl)-1,3-oxazolidine-2-thione, whose chemical formulae is C6H11NOS. Topics discussed include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters. It is noted that functionalised dithiocarbamate ligands offer opportunities in crystal engineering.

The article discusses the crystal structure of tris[N,N-bis(2-hydroxyethyl)-dithiocarbamato-κ2S,S']-chromium(III), whose chemical formulae is C15H30CrN3O6S6. Topics discussed, include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters.