catena-Poly[bis-(sulfamethoxazolium) [[trichloridocadmate(II)]-µ-chlorido] monohydrate].

In the title compound, {(C(10)H(12)N(3)O(3)S)(2)[CdCl(4)]·H(2)O}(n), the Cd(II) atom is five-coordinate with a distorted trigonal-bipyramidal geometry formed by chloride ions. The Cd atom and two of the Cl atoms lie on a mirror plane. The cation is protonated on the amino group N atom; it is not coordinated to cadmium, but is hydrogen bonded to the chlorido ligands. Each water mol-ecule bridges two chlorido ligands, generating ring motifs along the -Cd-Cl-Cd- chains. The isoxazole unit and the amide groups are linked through a pair of N-H⋯N hydrogen bonds. The crystal structure is stabilized by N-H⋯O, O-H⋯Cl, C-H⋯N, N-H⋯Cl and C-H⋯O hydrogen bonds.

Unusual cyclolanostanes from leaves of Pandanus boninensis.

Two unusual triterpenoids, (24S)-24-methyl-25,32-cyclo-5alpha-lanosta-9(11)-en-3beta-ol and (24S)-24-methyl-25,32-cyclo-cycloartane-3beta-ol, were isolated from leaves of Pandanus boninensis along with known triterpenoids and lignans. Their structures were established on the basis of spectroscopic methods and X-ray analysis.

Stereoselective Synthesis of Optically Active 2-Hydroxymandelic Acids and Esters via Friedel-Crafts Coordinated Reaction: Crystal Structure of Chiral Dichloro[2-(1-oxido-1-menthoxy- carbonylmethyl)-4-methoxyphenoxido-O,O,O]titanium.

Highly diastereoselective hydroxyalkylation of phenols with chiral glyoxylates was performed. Hydrolysis or reduction of the esters 3 afforded 2-hydroxymandelic acids 6 and diols 5 in high yields and enantiomeric pure form. Mechanistic evidence of chelation-controlled reaction comes from the crystal structure determination of titanium phenoxide complex 8.

Hierarchy of hydrogen bonding in bis(1,4,7-trioxa-10-azoniacyclododecane) bis(4-aminobenzoate) trihydrate.

In the title compound, 2C8H18NO3+.2C7H6NO2-.3H2O, proton transfer occurs from the carboxylic acid group of the 4-aminobenzoic acid (PABA) molecule to the amine group of the macrocycle, resulting in the formation of a salt-like adduct. The anions are combined into helical chains which are further bound by the water molecules into sheets. The macrocyclic cations are situated between these layers and are bound to the anions both directly and via bridging water molecules. The structure exhibits a diverse system of hydrogen bonding.

N-acetyl-4-[(2-hydroxybenzylidene)amino]benzenesulfonamide monohydrate and N-acetyl-4-[(5-bromo-2-hydroxybenzylidene)amino]benzenesulfonamide monohydrate.

Molecules of the title compounds, C15H14N2O4S.H2O and C15H13BrN2O4S.H2O, adopt an E configuration about the azomethine C=N double bond. In both molecules, the two benzene rings and the azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving the hydroxy O atom and azomethine N atom. The angular disposition of the bonds about the S atom deviates significantly from that of a regular tetrahedron. In the crystal structures, both compounds form two-dimensional layers parallel to the (100) plane.

2,4-dithiouracil: the reproducible H-bonded structural motifs in the complexes with 18-membered crown ethers.

2,4-dithiouracil (DTU) forms in the crystals the H-bonded monohydrates of a 1:1:1 ratio with 18-crown-6 (18C6) 1, cis,syn,cis-isomer of dicyclohexano-18-crown-6 (DCH6A) 2, and benzo-18-crown-6 (B18C6) 3, while the anhydrous adduct with cis,anti,cis-isomer of dicyclohexano-18-crown-6 (DCH6B) 4 is of a 2:1 ratio. In 1-3 the components reproducibly alternate in the chains, while in 4 the chains are built of the alternative centrosymmetric dimers of 2,4-dithiouracil and the molecules of the cis,anti,cis-isomer of dicyclohexano-18-crown-6.

Hydrogen-bonded supramolecular motifs in 4,4'-bipyridinium 8-hydroxy-7-iodoquinoline-5-sulfonate dihydrate.

In the title compound, C(10)H(9)N(2)(+).C(9)H(5)INO(4)S(-).2H(2)O, the 4,4'-bipyridine molecule is protonated at one of the pyridine N atoms. These moieties self-assemble into a supramolecular chain along the a axis through N-H.N hydrogen bonds. The quinolinol OH group acts as a donor with respect to a sulfonate O atom [O-H.O(sulfonate)] and acts as an acceptor with respect to a C-H group of ferron [C-H.O(hydroxy)], forming a supramolecular chain along the b axis. These two types of supramolecular chains (one type made up of bipyridine motifs and the other made up of sulfoxine motifs) interact via pi-pi stacking, generating a three-dimensional framework. These chains are further crosslinked by C-H.O hydrogen bonds and O-H.O hydrogen bonds involving water molecules.

The monoclinic polymorph of rac-5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazoniacyclotetradecane bis(hexafluorogermanate) tetrahydrate.

X-ray data were obtained for the monoclinic polymorph of rac-5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazoniacyclotetradecane bis(hexafluorogermanate) tetrahydrate, (C(16)H(40)N(4))[GeF(6)](2).4H(2)O. The tetraaza-macrocyclic cations lie across inversion centers in space group P2(1)/c. Water molecules and [GeF(6)](2-) anions form zigzag chains, which alternate in a three-dimensional network with the macrocyclic cations. The structure is sustained by multiple hydrogen bonds.