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The ruthenium(II) compounds cis-[Ru(bpy)2(4-bzpy)(CO)](PF6)2 (I) and cis-[Ru(bpy)2(4-bzpy)(Cl)](PF6) (II) (4-bzpy=4-benzoylpyridine, bpy=2,2'-bipyridine) were synthesized and characterized by spectroscopic and electrochemical techniques. The crystal structure of II was determined by X-ray diffraction. The photochemical behavior of I in aqueous solution shows that irradiation with ultraviolet light (365nm) releases both CO and 4-bzpy leading to the formation of the cis-[Ru(bpy)2(H2O)2]2+ ion as identified by NMR and electronic spectroscopy. Carbon monoxide release was confirmed with the myoglobin method and by gas chromatographic analysis of the headspace. CO release was not observed when aqueous I was irradiated with blue light (453nm). Changes in the electronic and 1H NMR spectra indicate that I undergoes photoaquation of 4-bzpy to form cis-[Ru(bpy)2(CO)(H2O)]2+. Blue light irradiation of aqueous II released the coordinated 4-bzpy to give the cis-[Ru(bpy)2(H2O)(Cl)]2+ ion. When the latter reaction was carried out in the presence of the nucleobase guanine, Ru-guanine adducts were formed, indicating that the metal containing photoproduct may also participate in biologically relevant reactions. The photochemical behavior of I indicates that it can release either CO or 4-bzpy depending on the wavelength chosen, a feature that may have therapeutic application.

The synthesis and structural characterization of three families of coordination complexes synthesized from 4′‐phenyl‐2,2′:6′,2′′‐terpyridine (8, Ph‐TPY), 4′‐(4‐chlorophenyl)‐2,2′:6′,2′′‐terpyridine (9, ClPh‐TPY) and 4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine (10, MeOPh‐TPY) ligands with the divalent metals Co2+, Fe2+, Mn2+ and Ni2+ are reported. The compounds were synthesized from a 1:2 mixture of the metal and ligand, resulting in a series of complexes with the general formula [M(R‐TPY)2](ClO4)2 (where M = Co2+, Fe2+, Mn2+ and Ni2+, and R‐TPY = Ph‐TPY, ClPh‐TPY and MeOPh‐TPY). The general formula and structural and supramolecular features were determinated by single‐crystal X‐ray diffraction for bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)nickel(II) bis(perchlorate), [Ni(C21H15N3)2](ClO4)2 or [Ni(Ph‐TPY)2](ClO4)2, bis[4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine]manganese(II) bis(perchlorate), [Mn(C22H17N3O)2](ClO4)2 or [Mn(MeOPh‐TPY)2](ClO4)2, and bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)manganese(II) bis(perchlorate), [Mn(C21H15N3)2](ClO4)2 or [Mn(Ph‐TPY)2](ClO4)2. In all three cases, the complexes present distorted octahedral coordination polyhedra and the crystal packing is determined mainly by weak C—H...π interactions. All the compounds (except for the Ni derivatives, for which FT–IR, UV–Vis and thermal analysis are reported) were fully characterized by spectroscopic (FT–IR, UV–Vis and NMR spectroscopy) and thermal (TGA–DSC, thermogravimetric analysis–differential scanning calorimetry) methods. [ABSTRACT FROM AUTHOR]

The chemical reaction of 4-bromo-benzoyl-chloride and 2-amino-thia-zole in the presence of potassium thio-cyanate yielded a white solid formulated as C15H10BrN3OS2, which consists of 4-bromo-benzamido and 2-benzo-thia-zolyl moieties connected by a thio-urea group. The 4-bromo-benzamido and 2-benzo-thia-zolyl moieties are in a trans conformtion (sometimes also called s-trans due to the single bond) with respect to the N-C bond. The dihedral angle between the mean planes of the 4-bromo-phenyl and the 2-benzo-thia-zolyl units is 10.45 (11)°. The thio-urea moiety, -C-NH-C(=S) -NH- fragment forms a dihedral angle of 8.64 (12)° with the 4-bromo-phenyl ring and is almost coplanar with the 2-benzo-thia-zolyl moiety, with a dihedral angle of 1.94 (11)°. The mol-ecular structure is stabilized by intra-molecular N-H⋯O hydrogen bonds, resulting in the formation of an S(6) ring. In the crystal, pairs of adjacent mol-ecules inter-act via inter-molecular hydrogen bonds of type C-H⋯N, C-H⋯S and N-H⋯S, resulting in mol-ecular layers parallel to the ac plane. [ABSTRACT FROM AUTHOR]

This study reports on the synthesis and characterization of two new coordination compounds of the active pharmaceutical ingredient metformin and transition metals. The cobalt compound with the formula [Co(Met)3][CoCl4]Cl·3H2O is a complex salt formed by a cationic Co(III) octahedral and anionic Co(II) tetrahedral subunits. The Cu(II) complex is represented by the formula [(Cu(Met)Cl)2-μ-Cl2] and is a dimeric compound with two chloride anions acting as a bridge, forming shared-edge square pyramidal units. Both compounds were characterized by single crystal X-ray diffraction, FT-IR spectroscopy and thermal analysis. [ABSTRACT FROM AUTHOR]

Herein, we report on the synthesis and characterization of ruthenium compounds with the general formula [RuCl(AA-H)(NO)(dppb]PF6, where AA = glycine (1), L-alanine (2), L-phenylalanine (3) and L-valine (4), and dppb = 1,4-bis(diphenylphosphine)butane. The complexes were characterized using elemental analysis, UV/Vis and infrared spectroscopies, 1H, 13C, 31P NMR techniques, and cyclic voltammetry. Furthermore, the structures of the compounds (1) and (3) were determined using single-crystal X-ray diffraction. In vitro evaluation of the Ru(II)/nitrosyl/amino acid complexes revealed their cytotoxic activities against triple-negative MDA-MB-231 breast cancer cells, and against the non-tumor murine fibroblast cells. All the compounds decreased the percentage of viable cells, inducing cell death by apoptosis. Additionally, the Ru(II) complexes inhibited the migration of MDA-MB-231 cells at concentrations lower than 35 µM, after 48 h of exposure. Thus, these complexes may be promising agents for the treatment of triple-negative MDA-MB-231 breast cancer. [ABSTRACT FROM AUTHOR]

Reaction of Li(P3C2Bu t2 ) with BrCH(SiMe3)2 results in a novel organophosphorus compound with the formula, P6C4Bu t4 CHSiMe3 (1). Compound 1 was fully characterised spectroscopically and its unique molecular structure determined by single crystal X-ray diffraction. Another isomer (2) with a saturated structure was also fully characterised.

Three principal factors may influence the final structure of coordination polymers (CPs): (i) the nature of the ligand, (ii) the type and coordination number of the metal center, and (iii) the reaction conditions. Further, flexible carboxylate aliphatic ligands have been widely employed as building blocks for designing and synthesizing CPs, resulting in a diverse array of materials with exciting architectures, porosities, dimensionalities, and topologies as well as an increasing number of properties and applications. These ligands show different structural features, such as torsion angles, carbon backbone number, and coordination modes, which affect the desired products and so enable the generation of polymorphs or crystalline phases. Additionally, due to their large coordination numbers, using 4f and 5f metals as coordination centers combined with aliphatic ligands increases the possibility of obtaining different crystal phases. Additionally, by varying the synthetic conditions, we may control the production of a specific solid phase by understanding the thermodynamic and kinetic factors that influence the self-assembly process. This revision highlights the relationship between the structural variety of CPs based on flexible carboxylate aliphatic ligands and f-elements (lanthanide and actinides) and their outstanding luminescent properties such as solid-state emissions, sensing, and photocatalysis. In this sense, we present a structural analysis of the CPs reported with the oxalate ligand, as the one rigid ligand of the family, and other flexible dicarboxylate linkers with –CH2– spacers. Additionally, the nature of the luminescence properties of the 4f or 5f-CPs is analyzed, and finally, we present a novel set of CPs using a glutarate-derived ligand and samarium, with the formula [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2]•(2,2′-bipy) (α-Sm) and [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2] (β-Sm). [ABSTRACT FROM AUTHOR]

Menezesite, ideally [Ba.sub.2]Mg[Zr.sub.4]([Ba[Nb.sub.12][O.sub.42]) *12[H.sub.2]O, occurs as a rug mineral in the contact zone between dolomite carbonatite and 'jacupirangite' (=a pyroxenite) at the Jacupiranga mine, in Cajati county, Sao Paulo state, Brazil, associated with dolomite, calcite, magnetite, clinohumite, phlogopite, ancylite-(Ce), strontianite, pyrite, and tochilinite. This is also the type locality for quintinite-2H. The mineral forms rhombododecahedra up to 1 mm, isolated or in aggregates. Menezesite is transparent and displays a vitreous luster; it is reddish brown with a white streak. It is non-fluorescent. Mohs hardness is about 4. Calculated density derived from the empirical formula is 4.181 g/[cm.sup.3]. It is isotropic, [n.sub.means]> 1.93(1) (white light); [n.sub.calc] = 2.034. Menezesite exhibits weak anomalous birefringence. The empirical formula is [([Ba.sub.147][K.sub.0.53][Ca.sub.0.31][Ce.sub.0.17] [Nd.sub.0.10][Na.sub.0.06][La.sub.0.02]).sub.[SIGMA]2.66] [([Mg.sub.0.94][Mn.sub.0.23][Fe.sub.0.3] [Al.sub.0.03]).sub.[SIGMA]1.43]([[Zr.sub.2.75] [Ti.sub.0.96][Th.sub.0.29).sub.[SIGMA]4.00 [[([Ba.sub.0.72][Th.sub.0.26][U.sub.0.02]).sub.[SIGMA]1.00] [([Nb.sub.9.23][Ti.sub.2.29][Ta.sub.0.36] [Si.sub.0.12]).sub.[SIGMA]12.00][O.sub.42]*12[H.sub.2]O. The mineral is cubic, space group Im [bar.3] (204), a = 13.017(1) [Angstrom], V = 2206(1) [[Angstrom].sup.3] Z = 2. Menezesite is isostructural with the synthetic compound [Mg.sub.7][Mg[W.sub.12][O.sub.42]][(OH).sub.4]*8[H.sub.2]O. The mineral was named in honor of Luiz Alberto Dias Menezes Filho (born 1950), mining engineer, mineral collector and merchant. Both the description and the name were approved by the CNMMN-IMA (Nomenclature Proposal 2005-023). Menezesite is the first natural heteropolyniobate. Heteropolyanions have been employed in a range of applications that include virus-binding inorganic drugs (including the AIDs virus), homogeneous and heterogeneous catalysts, electro-optic and electrochromic materials, metal and protein binding, and as building blocks for nanostructuring of materials. Keywords: Menezesite, new mineral, polyoxometalates, heteropolyniobate, heteropolyanions, crystal structure, chemical composition, Jacupiranga mine, Cajati, Brazil

Matioliite, ideally NaMg[Al.sub.5][(P[O.sub.4]).sub.4][(OH).sub.6] x 2[H.sub.2]O, occurs as a secondary hydrothermal mineral in the Gentil mine granite pegmatite, Mendes Pimentel Co., Minas Gerais, Brazil. Some crystals are zoned to more Fe-rich compositions with an [Fe.sup.2+]:Mg ratio of approximately 1:1, corresponding to an intermediate member of the burangaite-matioliite solid-solution series. Matioliite is intimately associated with fluorapatite, crandallite, and zoned gormanite-souzalite cystals. The mineral forms prismatic to tabular crystals, up to 1 mm long. Matioliite is transparent and displays a vitreous luster; it is blue to colorless with a white streak. It is non-fluorescent. Mohs hardness is about 5. Calculated density is 2.948 g/[cm.sup.3]. Matioliite is biaxial negative, [[eta].sub.[alpha]] = 1.597(2), [[eta].sub.[beta]] = 1.627(2), [[eta].sub.[gamma]] = 1.632(1) (white light), 2V (meas.) = 43(2)[degrees], 2V (calc.) = 44[degrees], dispersion r > v, orientation X = b, Z ^ c = 6[degrees]. Pleochroism is Y > X > Z, X = light blue to colorless, Y = blue, Z = colorless. The empirical formula is [([Na.sub.0.94][Ca.sub.0.01]).sub.[summation]0.95 [([Mg.sub.0.88][Fe.sup.2+.sub.0.11][Mn.sub.0.01].sub.[summation]1.00] [([Al.sub.4.84][Fe.sup.3+.sub.0.13]).sub.[summation]4.97] [(P[O.sub.4]).sub.4.03][(OH).sub.5.76] x 2[H.sub.2]O. The mineral is monoclinic, space group C2/c, a = 25.075(1) [Angstrom], b = 5.0470(3) [Angstrom], c = 13.4370(7) [Angstrom], [beta] = 110.97(3)[degrees], V = 1587.9(4) [[Angstrom].sup.3], Z = 4. Crystal-structure determination was carried out and showed it is isostructural with burangaite, dufrenite, and natrodufrenite. Both the description and the name were approved by the CNMMN-IMA (Nomenclature Proposal 2005-011). The 'magnesium analog of burangaite' described from the Gold Quarry mine, Carlin-trend, Eureka County, Nevada; 'burangaite' from Hochgosch, Millstatter See-Rucken, Karnten, Austria; and 'burangaite' described from Corrego Pomarolli, Linopolis, Divino das Laranjeiras, Minas Gerais, Brazil, are probably matioliite. Keywords: Matioliite, new mineral, crystal structure, burangaite, chemical composition, Gentil mine, Mendes Pimentel, Brazil

Described are the synthesis and characterization of Ru(II) complexes of the type Ru[Cl.sub.2][L.sub.2](N-O), where [L.sub.2] is either 1,4-bis (diphenylphosphino)butane (dppb) or [(P[Ph.sub.3]).sub.2], and N-O represents chelated 2-benzoylpyridine (2-bzpy) or 2-acetylpyridine (2-acpy); the Ru presursors used were [Ru[Cl.sub.2][(dppb)].sub.2] ([mu]-dppb) or Ru[Cl.sub.2][(P[Ph.sub.3]).sub.3]. The crystal structure of cis-Ru[C1.sub.2](dppb)(2-bzpy) is presented, and three other Ru[Cl.sub.2][L.sub.2](N-O) complexes with cis-chlorines are isolated and characterized spectroscopically; of the trans-dichloro species, Ru[Cl.sub.2][(P[Ph.sub.3]).sub.2](N-O) complexes are isolated, while the corresponding dppb species are characterized in situ. In all cases, thermodynamically stable cis-complexes are formed from initially formed trans-species. Key words: ruthenium, phosphines, 2-benzoylpyridine, 2-acetylpyridine, X-ray structures.

The ruthenium(II) complex, [Ru[Cl.sub.2](NO)L] (I), (L = [[(2-py).sub.2]P[C.sub.2][H.sub.4]P[O.sub.2](2-py)]-) was obtained from recrystallization of Ru[Cl.sub.3]NO(d2pype) (d2pype = [(2-py).sub.2]P[C.sub.2][H.sub.4]P[(2-py).sub.2]) in the presence of HN[O.sub.3], crystallizing in the monoclinic space group [P2.sub.1] (no. 4), with a = 8.012(4) [Angstrom], b = 14.454(4) [Angstrom], c = 9.353(3) [Angstrom], [beta] = 105.77(3)[degrees], and Z = 2. Crystals of the DMSO solvate of the complex (II) were obtained from [(C[D.sub.3]).sub.2]SO solution, crystallizing in the monoclinic space group [P2.sub.1]/c (no.14) with a = 9.7080(2) [Angstrom], b = 22.2920(5) [Angstrom], c = 11.5230(3) [Angstrom], [beta] = 92.0450(10)[degrees], and Z = 4. In both complexes, the geometry about the ruthenium atom is a distorted octahedron mainly as a result of the tridentate [P,N,O]-bonding mode of L. The v (NO) bands at 1875 [cm.sup-1] in both complexes are consistent with the linear disposition of the NO group and the Ru atom as is observed in the X-ray crystal structure (Ru-N1-O1 angle = 178.5(4)[degrees]). Key words: pyridylphosphine, nitrosyl, ruthenium complex, X-ray structure.