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The present study was undertaken in normotensive anaesthetized male rats that received a continuous perfusion of a chrysin glucoside isolated from the flowers and leaves of Calycotome villosa subsp intermedia at a dose of 2.5 mg/kg, or furosemide (control diuretic) at a dose of 0.5 mg/kg. Compared with the control rats receiving NaCl (0.9%), the urine flow, glomerular filtration and electrolyte excretion (Na+, K+) increased significantly in rats treated with chrysin glucoside ( p < 0.001). A similar effect was observed in the rats perfused with furosemide. Intravenous injections of bolus doses (1-3 mg/kg) of the chrysin glucoside to anaesthetized rats elicited an immediate and dose-dependent decrease in mean arterial blood pressure (MABP). Pretreatment of the rats with the nitric oxide synthase inhibitor, l-NOArg (10 mg/kg), reduced partially, but significantly ( p < 0.01), the maximal decrease in MABP elicited by chrysin glucoside. In the rat isolated aorta preparation, chrysin glucoside (10-100 µ m) inhibited in a concentration-dependent manner the noradrenaline (1 µ m) induced contractions (IC50 = 52 µ m). This relaxant activity of chrysin glucoside was significantly reduced by incubation of the endothelium-intact rings with l-NOArg (100 µ m), (80 ± 4.7% vs 48 ± 5.06% in the absence of l-NOArg). In conclusion, these results demonstrate a diuretic and hypotensive action of a chrysin glucoside from Calycotome villosa in anaesthetized rats and indicating an action on renal function, and an active vascular relaxation mediated partially through nitric oxide release. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title mol-ecular salt [systematic name: 1,4,8,11-tetraazacyclotetradecane-1,8-diium bis(3-carboxy-prop-2-enoate)], C10H26N4 (2+)·2C4H3O4 (-), contains two half-cations (both completed by crystallographic inversion symmetry) and two maleate anions. The cyclam macrocycles adopt trans-III conformations, supported by two intra-molecular N-H⋯O hydrogen bonds. The O-bonded H atom of each maleate ion is disordered over two positions with an occupancy ratio of 0.61 (5):0.39 (5): each one generates an intra-molecular O-H⋯O hydrogen bond. In the crystal, the cations are linked to the anions by N-H⋯O hydrogen bonds, generating [001] chains.

The asymmetric unit of the title compound, C(12)H(17)NO(3), contains two mol-ecules with different conformations. It is a polymorph of the monoclinic form [El Antri et al. (2004 ▶). Mol-ecules, 9, 650-657]; the samples were crystallized at different temperatures from the same solvent. In both structures, mol-ecules are linked by O-H⋯N hydrogen bonds, forming chains. The conformations of the chains and their packing differ markedly in the two polymorphs.

The crystal structure of the title compound, C(7)H(10)N(+)·H(2)PO(3) (-), has been reported previously by Sabounchei & Naghipour [Asian J. Chem. (2003) ▶, 15, 1677-1686]. A new look at this compound has revealed doubling of the unit cell. The asymmetric unit consists of two 4-methyl-anilinium cations and two dihydrogen phosphite anions. The crystal structure is built upon alternating layers of organic cations and dihydrogen phosphite anions stacked along c. The organic layer is stabilized by C-H⋯π interactions. Weak aromatic π-π stacking interactions with centroid-centroid distances of 4.6147 (12), 4.6917 (12), 4.6932 (13) and 4.8366 (13) Å are also observed in the structure. The dihydrogen phosphite anions are linked by O-H⋯O hydrogen bonds into chains running parallel to the a-axis direction. These chains are connected to the cation layer by N-H⋯O hydrogen bonds.

In the title compound, Pb(2)(HPO(3))(NO(3))(2), the two distinct Pb(2+) ions (both with site symmetry m) adopt irregular PbO(10) coordination polyhedra. The structure is completed by two distinct nitrate groups (in which one O atom and the N atom have m site symmetry for both ions) and an HPO(3) (2-) anion (in which one O atom and the P and H atoms have m site symmetry). The connectivity of the PbO(10), NO(3) and HPO(3) units in the crystal structure results in a three-dimensional network.

The title compound, Cs(2)Mg(H(2)P(2)O(7))(2)·2H(2)O, is isostructural with the related known isoformular phosphates. The crystal framework consists of corner-sharing MgO(6) and H(2)P(2)O(7) polyhedra, leading to tunnels parallel to the b-axis direction in which Cs(+) ions are located. The H(2)P(2)O(7) unit shows a bent eclipsed conformation. The Mg(2+) ion lies on an inversion center. The water molecules form hydrogen bonds to O atoms of two different dihydrogenphosphate ions, which are further hydrogen bonded to symmetry-equivalent dihydrogenphosphate ions.

The crystal structures of three isotypic orthorhombic dihydrogendiphosphates, namely dipotassium copper(II)/nickel(II)/zinc(II) bis(dihydrogendiphosphate) dihydrate, K2M(H2P2O7)2.2H2O (M = Cu, Ni and Zn), have been refined from single-crystal data. The M2+ and K+ cations are located at sites of m symmetry, and the P atoms occupy general positions. These compounds also exist in triclinic forms with very similar structural features. The structures of both forms are compared, as well as the geometry of the MO6 octahedron, which is considerably elongated towards the water molecules for M = Ni and Cu. Such elongation has not been observed among the other representatives of the family. A Raman study of the whole series K2M(H2P2O7)2.2H2O (M = Mn, Co, Ni, Cu, Zn and Mg) is reported.

The title compound, [Ag(C(3)H(5)OS(2))](n), is polymeric in the solid state and adopts a layered structure in which each Ag atom is five-coordinated in a distorted trigonal-bipyramidal geometry defined by four S atoms belonging to four different xanthate groups and by a neigbouring Ag atom [Ag.Ag = 3.0540 (8) A]. Each S atom is three-coordinated to one C and two Ag atoms. The structure can be envisaged as being formed by Ag(2)(S(2)COEt)(2) units in which every S atom is bonded to another Ag atom from a different unit and the Ag atoms are also bonded to two different S atoms of two other units. The result is a two-dimensional network of condensed metallacycles of six or eight atoms.

The Pd atom in the title compound, [Pd(C(3)H(5)OS(2))(2)], lies on an inversion center and adopts a square-planar coordination geometry defined by the four S atoms of the two dithiocarbonate (xanthate) ligands. In the solid state, the molecules aggregate into layers in which the rows of molecules alternate their orientation to allow each Pd atom to interact with two symmetry-equivalent S atoms of the xanthate ligands of adjacent molecules, generating a pseudo-octahedral environment around each Pd atom. This weak interaction of 3.3579 (7) A can be classified as a closed-shell electrostatic intermolecular interaction.

A new triclinic polymorphic modification of the title compound, [Ag(C(3)H(5)OS(2))(C(18)H(15)P)(2)], has been found and compared with the previously known orthorhombic modification [Tiekink (1988). Coord. Chem. 17, 239-243]. The two polymorphs have the same molecular shape, viz. a distorted tetrahedral geometry, with a chelating dithiocarbonate (xanthate) and two PPh(3) ligands bonded to the Ag atom. However, in this new polymorph, the xanthate ligand is bonded asymmetrically to the Ag atom, with Ag-S distances of 2.5489 (6) and 2.8055 (7) A, while for the orthorhombic polymorph these distances are 2.686 (4) and 2.601 (4) A. The Ag-P distances are similar in both structures.