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Fluoride is one of the drinking water contaminants regulated by the World Health Organization. The reduction of fluoride concentration to a safe range is of paramount importance to human life. Moreover, the fast and high-capacity removal of radioactive 18F wastes is still challenging. Metal organic frameworks (MOFs) are a hybrid class of materials that can diminish such contaminants via both adsorption and catalysis processes. In this work, we synthesize three different MOFs and study their adsorption behavior towards fluoride ion removal. The synthesized materials were characterized using X-ray diffraction, FT-IR and scanning electron microscopy. Following investigation we showed that the assynthetized materials were highly stable and had significantly effective fluoride adsorption performance What is more, the activity of fluoride captured by the material Al-Fu MOF is 603 µCi in 40 mg of this material, i.e., the removal efficiency is about 98%. [ABSTRACT FROM AUTHOR]

A novel bisphosphonate derivative (1-aminoethane-1,1-diyl)diphosphonic acid (AEDP) has been prepared and successfully labeled with 99mTc at high labeling yields. The in vivo biodistribution of 99mTc-AEDP has been investigated and compared with two reference compounds Tc-99m methylene diphosphonate (99mTc-MDP) and Tc-99m (1-hydroxyethylidene) diphosphonate (99mTc-HEDP). The biodistribution studies have demonstrated a high uptake of the radiotracer 99mTc-AEDP in the bone and a rapid clearance from the blood (such as the two technetium-labeled bone imaging agents in current use: 99mTc-MDP and 99mTc-HEDP). Additionally, the scintigraphic images of 99mTc-AEDP in normal rats have revealed high selective skeletal uptake.

The title two-dimensional coordination polymer, [Na(C2H8NO6P2)] n, was characterized using powder X-ray diffraction data and its structure refined using the Rietveld method. The asymmetric unit contains one Na+ cation and one (1-azaniumylethane-1,1-diyl)bis(hydrogen phosphonate) anion. The central Na+ cation exhibits distorted octahedral coordination geometry involving two deprotonated O atoms, two hydroxy O atoms and two double-bonded O atoms of the bisphosphonate anion. Pairs of sodium-centred octahedra share edges and the pairs are in turn connected to each other by the biphosphonate anion to form a two-dimensional network parallel to the (001) plane. The polymeric layers are connected by strong O-H...O hydrogen bonding between the hydroxy group and one of the free O atoms of the bisphosphonate anion to generate a three-dimensional network. Further stabilization of the crystal structure is achived by N-H...O and O-H...O hydrogen bonding. [ABSTRACT FROM AUTHOR]

The structure of the title benzovesamicol analogue, C21H27N3O2, an important compound for the diagnosis of Alzheimer's disease, has been determined by X-ray powder diffraction. The title compound was firstly synthesized and characterized by spectroscopic methods (FT-IR, and 13C and 1H NMR). The compound is a racemic mixture of enantiomers which crystallizes in the monoclinic system in a centrosymmetric space group ( P21/ c). Crystallography, in particular powder X-ray diffraction, was pivotal in revealing that the enantio-resolution did not succeed. The piperazine ring is in a chair conformation, while the cyclohexene ring assumes a half-chair conformation. The crystal packing is dominated by intermolecular O-H...N hydrogen bonding which links molecules along the c direction. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis and crystallization of 2,2,2-trifluoro-N-(1a,2,7,7a-tetra-hydronaphtho[2,3-b]oxiren-3-yl)-acetamide through X-ray powder diffraction. A figure showing the molecular structure with the atomic numbering scheme and displacement ellipsoids is presented. Three stages of crystal structure determination from diffraction include unit-cell determination and space-group assignment, structure solution and structure refinement. The geometry of hydrogen bond and selected geometric parameters are presented in tables.

In the title compound, [CdL 2(H2O)4]·2H2O [L = (1-ammonio-1-phosphono-eth-yl)phospho-nate, C2H8NO6P2 (-)], the Cd(II) ion is situated on an inversion centre being coordinated by four aqua mol-ecules in the equatorial plane and two phosphonate O atoms from two deprotonated L ligands in the axial positions in a distorted octa-hedral geometry. The asymmetric unit contains one-half of the complex mol-ecule and one lattice water mol-ecule. The ligand L exists in a zwitterionic form, with a positive charge on the NH3 group and a negative charge on the O atom of the non-coordinating phospho-nate group, and with an intra-molecular O-H⋯O inter-action forming an S(6) ring motif and two intra-molecular N-H⋯O inter-actions each generating an S(5) ring motif. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the complex mol-ecules into a three-dimensional network in which the voids of 38 Å(3) are filled with ordered lattice water mol-ecules, which are also involved in O-H⋯O hydrogen bonding.

The title compound, [Na(2)(C(2)H(8)NO(6)P(2))Cl(H(2)O)(2)](n), has a polymeric two-dimensional structure extending parallel to (001). The asymmetric unit contains two Na(+) cations located on a centre of symmetry and on a mirror plane, respectively, one half of a bis-phospho-nate anion (the entire anion is completed by mirror symmetry), one chloride anion on a mirror plane and one water mol-ecule in general positions. The two Na(+) cations exhibit distorted octa-hedral NaCl(2)O(4) coordination polyhedra, each consisting of two deprotonated O atoms of the bis-phospho-nate anion, of two water mol-ecules and of two chloride anions. Strong O-H⋯O hydrogen bonds between the -OH group and one of the free O atoms of the bis-phospho-nate anion connect adjacent layers along [100], supported by N-H⋯Cl inter-actions. Intra-layer O-H⋯O and N-H⋯O hydrogen bonds are also observed.