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Tadeusz Lis

Publications and source records attributed to Tadeusz Lis.

27 records · Page 2Linked to original sources
PubMed2004

Crystal structures of dihydroxyacetone and its derivatives.

The crystal and molecular structures of three crystalline forms of the dihydroxyacetone dimer, C6H12O6, DHA-dimer: alpha (1a), beta (1b), and gamma (1c), the hydrated calcium chloride complex of dihydroxyacetone monomer, CaCl2(C3H6O3)(2) x H2O, CaCl2(DHA)2 x H2O (2a), the tetrahydrated calcium chloride complex of dihydroxyacetone monomer, CaCl2(C3H6O3) x 4H2O, CaCl2(DHA) x 4H2O (2b), the dihydroxyacetone monomer, C3H6O3, DHA (2c), and dihydroxyacetone dimethyl acetal, C5H12O4, (MeO)2DHA (3) are described. Compounds 1a and 2b crystallize in the triclinic system, and 1b,c, 2a,c, and 3 are monoclinic. Molecules of all forms of dihydroxyacetone dimer 1a,b, and 1c are the trans isomers, with the 1,4-dioxane ring in the chair conformation and the hydroxyl and hydroxymethyl groups in axial and equatorial dispositions, respectively. The Ca2+ ions in 2a and 2b are bridged by the carbonyl O atoms from two symmetry-related DHA molecules to form centrosymmetric dimers with Ca...Ca distance of 4.307(2)A in 2a and 4.330(2) and 4.305(2)A in two crystallographically independent dimers in 2b. DHA molecules coordinate to the Ca2+ ions by hydroxyl and carbonyl oxygen atoms. The eight-coordinate polyhedra of Ca2+ are completed by water molecule and Cl- ion in 2a and by four water molecules in 2b. The dihydroxyacetone molecules in 2a,b, and 2c are in an extended conformation, with both hydroxyl groups being synperiplanar (sp) to the carbonyl O atom. All hydroxyl groups in 2c (along with water molecules in 2a and 2b) are involved as donors in medium strong and weak intermolecular O-H...O hydrogen bonding. Some of them, as well as carbonyl O atoms or Cl- ions in 2a and 2b, act as acceptors in C-H...O (and C-H...Cl) hydrogen interactions.

Crystallography, X-Ray↗
PubMed2004

Potassium p-nitrophenyl sulfate.

The crystal structure of the title compound, K+.C6H4NO6S-, is built up from p-nitrophenyl sulfate anions and potassium cations. Adjacent anions form dimers, which are linked together in a three-dimensional network via short C-H...O contacts. The coordination sphere of the K+ ions may be described as a distorted square antiprism. The crystal structure is further stabilized by pi-pi stacking interactions between the aryl rings.

Crystallography, X-Ray↗
PubMed2004

5,5-Dimethoxy-2-phenoxy-1,3,2-dioxaphosphorinane 2-oxide.

In the title compound, C(11)H(15)O(6)P, the six-membered dioxaphosphorinane ring of the cyclic phosphate triester exists in a distorted chair conformation, with the phenoxy group in an axial position. The phenyl ring and both methoxy groups are in a trans-gauche orientation with respect to the 1,3,2-dioxaphosphorinane ring. In the phosphate group, a significant deformation from the ideal tetrahedral shape is observed. The crystal structure is stabilized by a three-dimensional network of C-H...O interactions.

Journal Article↗
PubMed2004

Polymeric sodium 3,5-dicarboxybenzenesulfonate-urea-water (1/1/1).

In the title compound, poly[sodium-mu(4)-3,5-dicarboxybenzenesulfonato-kappa4O:O':O":O"'-mu(2)-urea-kappa2O:N] monohydrate], [[Na(C8H5O7S)(CH4N2O)] x H2O]n, the organic anions are arranged almost vertically within (001) monolayers, with the sulfonate and carboxylic acid groups pointing into the interlayer region. The inversion-related aromatic rings of the anions inside the layers are arrayed via offset face-to-face interactions into molecular stacks along the crystallographic a axis. The 'up' and 'down' arrangement of the aromatic portions makes both faces of the layers ionic and hydrophilic, whereas the interiors of the layers are primarily hydrophobic. The interleaving of the anions is such that the carboxylic acid groups are oriented more toward the interior than are the sulfonate groups. The aromatic rings in neighbouring layers are arranged in a herring-bone fashion. The coordination sphere of the Na+ ions contains two sulfonate and two carboxylic acid O atoms, from a total of four different acid anions belonging to two neighbouring anionic monolayers. The urea molecules are positioned between translation-related anionic stacks inside the (001) layers, serving a triple function, viz. they fill in the large meshes (empty cavities) formed within the anionic-cationic network, and they provide additional Na+ coordination and hydrogen-bond sites.

Journal Article↗
PubMed2003

New rhodium(III) and ruthenium(II) water-soluble complexes with 3,5-diaza-1-methyl-1-azonia-7-phosphatricyclo[3.3.1.1(3,7)]decane.

The new water-soluble phosphine complexes of rhodium(III), [RhI(4)(mtpa)(2)]I (1), and ruthenium(II), [RuI(4)(mtpa)(2)].2H(2)O (2) and [RuI(2)(mtpa)(3)(H(2)O)]I(3).2H(2)O (3) (mtpa = 3,5-diaza-1-methyl-1-azonia-7-phosphatricyclo[3.3.1.1(3,7)]decane cation), have been prepared in the reactions of RhCl(3).3H(2)O and RuCl(3).3H(2)O in water in the presence of phosphine and potassium iodide. Properties and reactivity of the complexes have been investigated using (1)H and (31)P NMR and IR spectroscopies. The complexes have also been structurally characterized by single crystal X-ray diffraction studies. The compounds [RhI(4)(mtpa)(2)]I and [RuI(4)(mtpa)(2)].2H(2)O are zwitterionic octahedral complexes. The compounds were tested as catalysts for two-phase hydroformylation of 1-hexene and hydrogenation of cinnamaldehyde. Complex 1 is a selective catalyst for reduction of the C=C bond while complexes 2 and 3 selectively hydrogenate the C=O bond.

Journal Article↗
PubMed2003

Polymeric bis(phosphonomethylcarboxylato)calcium(II) at 85 K.

In the crystal structure of the title compond, alternatively called poly[calcium(II)-di-mu-carboxymethylphosphonato], [Ca(C(2)H(4)O(5)P)(2)](n) or [Ca(H(2)AP)(2)](n), one of the phosphonate O atoms of the phosphonocarboxylate monoanion lies nearly antiperiplanar (ap) to the carboxylic acid C atom. The phosphonate P atom is located -sc and +ac relative to the carboxylic acid O atoms. The overall structure has a layered architecture. The Ca(2+) cations lie on a twofold axis and are bridged by the phosphonate O atoms to form chains along the c axis, giving layers parallel to (100). There are medium-strength O-H...O and C-H...O hydrogen-bonding interactions stabilizing the layers, and O-H...O hydrogen bonds connect adjacent layers.

Journal Article↗
PubMed2002

Synthesis and X-ray structures of sulfate esters of fructose and its isopropylidene derivatives. Part 1: 2,3:4,5-di-O-isopropylidene-beta-D-fructopyranose 1-sulfate and 4,5-O-isopropylidene-beta-D-fructopyranose 1-sulfate.

2,3:4,5-Di-O-isopropylidene-beta-D-fructopyranose 1-sulfate have been synthesized by treatment of 2,3:4,5-di-O-isopropylidene-beta-D-fructopyranose with pyridine-sulfur trioxide complex. Direct hydrolysis of the isopropylidene group at C-4, C-5 gave 2,3-O-isopropylidene-beta-D-fructopyranose 1-sulfate. The crystal and molecular structures of ammonium (1a) and potassium (1b) salts of diisopropylidene derivative and ammonium (2) salt of monoisopropylidene derivative were determined by X-ray crystallography. Data for 1a and 1b were collected in 120 K and in 150 K for 2. All salts crystallized in P2(1)2(1)2(1) space group. There are three independent anions in asymmetric unit in 1b. Pyranose rings in the diisopropylidene derivative salts studied adopt 2S(0) twist boat conformation, whereas in the monoisopropylidene exists in a slightly distorted chair conformation (4C(1)). A staggered conformation is preferred by the sulfate group as indicated by values of C-(ester)-S-O(terminal) torsion angles: -173.2(4) degrees in 1a, 175.1(6) degrees in anion A of 1b, 170.8(6) degrees in anion C of 1b and 177.9(2) degrees in 2. However, strong interactions such as potassium-oxygen and H-bonds may affect the geometry: in anion B of 1b the value of the torsion angle is 139.4(6) degrees.

Alkenes↗
PubMed2002

Investigations on the synthesis and pharmacological properties of 4-alkoxy-2-[2-hydroxy-3-(4-aryl-1-piperazinyl)propyl]-6-methyl-1H-pyrrolo[3,4-c]pyridine-1,3(2H)-diones.

Synthesis of 2-[2-hydroxy-3-(4-aryl-1-piperazinyl)propyl] derivatives of 4-alkoxy-6-methyl-1H-pyrrolo[3,4-c]pyridine-1,3(2H)-diones (8-12) is described. The chlorides used in the above synthesis can exist in two isomeric forms: chain (18-20) and cyclic (19a, 20a). The compounds 8-12 exhibited potent analgesic activity which was superior than that of acetylsalicylic acid in two different tests. Most of the investigated imides suppressed significantly spontaneous locomotor activity in mice.

Analgesics, Non-Narcotic↗