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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]

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]

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.

In the title compound, [AgBr(C(7)H(10)N(2))](n), adjacent Ag(I) atoms are bridged by bidentate CNCH(2)C(CH(3))(2)CH(2)NC ligands via the NC groups, forming [Ag{CNCH(2)C(CH(3))(2)CH(2)NC}](n) chains with the metal atom in a distorted tetrahedral coordination. The bromide counter-anions cross-link the Ag(I) atoms of the chains, forming a two-dimensional polymeric network {[Ag(I)(CNCH(2)C(CH(3))(2)CH(2)NC)]Br}(n) extend-ing parallel to (010). The polymeric structure is similar to that of the very recently reported Cl(-), I(-) and NO(3) (-) analogues. This gives a strong indication that 2,2-dimethyl-propane-1,3-diyl diisocyanide is a potential ligand for giving polymeric structures on treatment with AgX (X = Cl(-), Br(-), I(-) or NO(3) (-)) regardless of the counter-anion used.

In order to investigate the effect of counter-anions on the polymeric structure of (2,2-dimethylpropane-1,3-diyl diisocyanide)silver(I) complexes, the novel title polymeric compound, [Ag(NO(3))(C(7)H(10)N(2))](n), has been synthesized. The crystal structure was determined by simulated annealing from X-ray powder diffraction data collected at room temperature. The current structure is similar to the recently reported structure of the analogue with chloride replacing nitrate. This study illustrates that both the chloride and nitrate complexes crystallize in the orthorhombic system in the Pbca space group with one monomer in the asymmetric unit, and also gives a strong indication that the counter-anion does not have a considerable effect on the polymeric structure of the complex. The Ag centre lies in a distorted tetrahedral environment and is bonded to two 2,2-dimethylpropane-1,3-diyl diisocyanide ligands to form chains. The nitrate anions crosslink the Ag centres of the chains to form a two-dimensional polymeric network structure.

Several independent synthetic routes are described leading to the formation of a novel unsaturated tetracyclic phosphorus carbon cage compound tBu4C4P6 (1), which undergoes a light-induced valence isomerization to produce the first hexaphosphapentaprismane cage tBu4C4P6 (2). A second unsaturated isomer tBu4C4P6 (9) of 1 and the bis-[W(CO)5] complex 13 of 1 are stable towards similar isomerization reactions. Another starting material for the synthesis of the hexaphosphapentaprismane cage tBu4C4P6 (2) is the trimeric mercury complex [(tBu4C4P6)Hg]3 (11), which undergoes elimination of mercury to afford the title compound 2. Single-crystal X-ray structural determinations have been carried out on compounds 1, 2, 9, 11, and 13.