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  • 2020-2024
  • 1995-1999  (79)
  • 1930-1934  (236)
  • 1920-1924
  • 1999  (79)
  • 1933  (236)
  • Cell & Developmental Biology  (236)
  • crystal structure  (79)
Datenquelle
Materialart
Erscheinungszeitraum
  • 2020-2024
  • 1995-1999  (79)
  • 1930-1934  (236)
  • 1920-1924
Jahr
Schlagwörter
  • 1
    Digitale Medien
    Digitale Medien
    Crystal structure of [Mn2(III)(salpa)2Cl2(H2O)2] (H2salpa = 1-(salicylaldeneamino)-3-hydroxypropane) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 203-206 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Manganese(III) ; Schiff base ; hydrogen bonding ; crystal structure ; Jahn-Teller distortion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The manganese complex, (Mn2(III)(salpa)2Cl2(H2O)2], has been prepared and its structure determined using x-ray crystallography. The dimer is a di-μ2-alkoxo complex which is a six-coordinate manganese dimer with unsupported alkoxide bridges and a rare example of a chloride- and water-containing manganese dimer. The complex crystallizes in the monoclinic space group P21/c with a = 9.315(5), b = 11.130(4), c = 11.637(5) Å, β = 104.33(3)°, V = 1169.0(9) Å3, and Z = 2. The structure comprises discrete binuclear clusters in which the metal atoms are bridged by two alkoxo oxygens of the salpa2− ligands. The Mn—O and Mn—N distances are in good agreement with those found for other manganese(III) Schiff base complexes. The Mn—Cl and Mn—O3 distances are 2.585(2) and 2.371(2) Å, respectively, and the Mn ··· Mn distance is 3.001(1) Å. In the crystal, there are two types of hydrogen bonding between the H2O molecule and the Cl atom with Cl ··· H(H2O) distance of 2.33(6) (intramolecule: −1 + x, y, −1 + z) and 2.68(6) Å (intermolecule: −1 + x, 0.5−y, −0.5 + z).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009526312170
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  • 2
    Digitale Medien
    Digitale Medien
    Molecular structure of ThBr4(DME)2 (DME = 1,2-dimethoxyethane) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 243-246 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Thorium ; dimethoxyethane ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The molecular structure of ThBr4(DME)2 (DME = 1,2-dimethoxyethane), the first structurally characterized thorium complex containing a simple bidentate ether ligand, is described. The eight-coordinate complex presents a distorted dodecahedral geometry, with Th—Br and Th—O bond lengths in the ranges 2.8516(13)–2.8712(13) Å and 2.564(8)–2.620(8) Å, respectively. ThBr4(DME)2 is monoclinic, space group P21/n, a = 7.672(1), b = 14.581(1), c = 15.847(2) Å, β = 102.24(1)°, V = 1732.4(3) Å3, and Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009542715804
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  • 3
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of the copper(II) complex with novel Schiff base ligand: Cu(C8H7O2N)2(OH2) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 295-298 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Copper ; crystal structure ; synthesis ; Schiff base ligand
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title complex Cu(C8H7O2N)2(OH2) crystallized in the orthorhombic space group, Pbca with unit cell parameters: a = 15.242(2), b = 11.782(4), c = 17.946(4) Å, and Z = 8. Two nitrogen atoms, two phenolic oxygen atoms of the ligand, and one water molecule are coordinated with copper to form a distorted tetragonal pyramidal polyhedron.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009569701034
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  • 4
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structures of quadruply carboxylate-bridged dimeric lanthanide(III) complexes of betaine (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 309-316 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Europium ; terbium ; betaine ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Three dimeric lanthanide(III) complexes, [Eu2(bet)8(H2O)4](CIO4)6 (1), [Tb2(bet)8(H2O)4](ClO4)6 (2), and [Eu2(bet)4(H2O)8] Cl6·6H2O (3) (bet = Me3N+CH2COO−, trimethyl-aminoacetate), have been prepared and structurally characterized by X-ray crystallography. Complex 1 crystallizes in the monoclinic space group P21/c, with a = 11.7807(8), b = 27.757(5), c = 11.7980(8) Å, β = 99.500(4)°, V = 3805.1(8) Å3, and Z = 2. Complex 2 is isomorphous to complex 1, crystallizing in the monoclinic space group P21/c, with a = 11.7769(14), b = 27.725(3), c = 11.795(5) Å, β = 99.668(14)°, V = 3797(2) Å3, and Z = 2. Complex 3 crystallizes in the orthorhombic space group Pbca, with a = 12.5664(8), b = 17.8645(9), c = 22.2573(8) Å, V = 4996.6(4) Å3 and Z = 4. Both complexes 1 and 2 comprise quadruply carboxylate-O,O′-bridged [M2(bet)4]6+ dimeric cores (M = Eu, Tb), and each metal ion is further coordinated by two terminal aqua ligands and two monodentate bet carboxylates to form a distorted square-antiprismatic coordination geometry. Complex 3 also has a [Eu2(bet)4]6+ core, in which two bet ligands act in the η1:η1:μ2 bridging fashion, and the other two bet ligands in the less common η2:η1:μ2 bridging fashion, namely bridging-chelate mode. Each europium(III) ion in complex 3 is further coordinated by four water molecules to complete a monocapped square antiprism.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009573801943
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  • 5
    Digitale Medien
    Digitale Medien
    Copper, a chemical Janus: two copper(II) complexes with different ligand in one single crystal (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1085-1088 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; copper(II) complexes ; dinuclear complexes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract A chemical Janus, binuclear copper(II) complexes, {[Cu(TPA)Cl][Cu(BPA)Cl]}(ClO4)2 (TPA = Tris(2-pyridylmethyl) amine, BPA = bis-(2-pyridylmethyl)amine) containing two different ligands has been synthesized and characterized by X-ray single crystal analysis. Crystal data: triclinic, space group P1$sm, a = 12.529(3), b = 12.655(3), c = 13.458(3) Å, α = 70.48(3), β = 67.40(3), γ = 75.81(3)°, D x = 1.648 mg m−3, and Z = 2. The molecular structure shows that the binuclear copper complex consists of two positive cation and two perchlorate anions. The positive cations moieties have different ligands. Cu(1) is coordinated by four nitrogen atoms from TPA and one chloride atom, forming a square-pyramidal geometry, whereas the coordinate number of Cu(2) is four, three of which are from BPA, one from chloride. There are two weak bonds between the Cl(2a) ion and the Cu(2) ion (2.844 Å) and the distance of Cu(2)=O(13) is 2.750(9) Å.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009549506565
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  • 6
    Digitale Medien
    Digitale Medien
    Molecular gears: Structures of (9,10-triptyceno) crown ethers (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 513-521 
    Details
    ISSN: 1572-8854
    Schlagwort(e): nanotechnology ; molecular devices ; triptycene ; crown ether ; crystal structure ; thallium
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The incorporation of 9,10-triptycene unit in a crown ether is examined from a structural perspective. Insertion of a triptycene group into 18-crown-6 stretches the crown into an ellipse, as seen in structures presented here of 9,10-triptyceno-22-crown-6 and its thallium complex. Symmetric addition of two triptycene groups into 18-crown-6 results in the sterically congested bis(9,10-triptyceno)-26-crown-6, whose crown cavity is filled with the π-clouds of two arene groups. The larger bis(9,10-triptyceno)-32-crown-8 is more sterically relaxed. The structures of these bis(triptyceno)crown ether molecules are the first with two triptycene groups simultaneously linked through their 9 and 10 positions, thereby forming a simple molecular gearing mechanism. The compound 9,10-triptyceno-22-crown-6 (1) crystallizes in the orthorhombic space group Pbca with a = 10.7962(7), b = 15.826(3), c = 31.147(5) Å, V = 5321.8(12) Å3, and Z = 8; its complex with TlNO3 (Tl-1) crystallizes in the monoclinic space group P21/c with a = 8.1884(14), b = 19.552(2), c = 20.575(4) Å, β = 97.062(8)°, V = 3269.2(9) Å3, and Z = 4; bis(9,10-triptyceno)-26-crown-6 (2) crystallizes in the triclinic space group P $$\bar 1$$ with a = 8.6488(11), b = 10.7718(12), c = 12.3324(12) Å, α = 111.58(1), β = 100.55(1), γ = 106.43(1)°, V = 970.3(5) Å3, and Z = 1; and bis(9,10-triptyceno)-32-crown-8 (3) crystallizes in the orthorhombic space group Pna21 with a = 20.186(3), b = 8.558(2), c = 25.623(2) Å, V = 4426.2(14) Å3, and Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009535632237
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  • 7
    Digitale Medien
    Digitale Medien
    The structure of bis(trimethylammonium) undecachlorotriantimonate(III) [(CH3)3NH]2Sb3Cl11 containing a novel antimony(III) anion (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 555-560 
    Details
    ISSN: 1572-8854
    Schlagwort(e): alkylammonium chloroantimonates(III) ; hydrogen bonds ; disorder ; lone electron pair ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The structure of [(CH3)3NH]2Sb3Cl11 (space group P21/n; a = 10.374(2), b = 23.723(5), c = 11.884(2) Å, β = 113.46(3)°; V = 2682.9(9) Å3) consists of a structurally novel [Sb3Cl2− 11] anion and two crystallographically nonequivalent trimethylammonium cations. The anion is composed of three deformed octahedra in the asymmetric part of the unit cell. The octahedra are connected with each other by edges and corners forming a characteristic polyanionic layer. Trimethylammonium cations, one ordered and one disordered, are connected to the inorganic sublattice by N—H· · ·Cl hydrogen bonds.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009592618124
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  • 8
    Digitale Medien
    Digitale Medien
    Crystal structure of the Λ-[4M] enantiomer of cis-diaqua-bis(1,3-dimethylpteridine-2,4(1H,3H)-dione-N5,O4) copper(II) perchlorate monohydrate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 571-574 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; complexes ; pteridine ; lumazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Single-crystal X-ray diffraction studies have been performed on the complex cis-diaqua-bis(1,3-dimethylpteridine-2,4(1H,3H)-dione-O4,N5) copper(II) perchlorate monohydrate, [Cu(DLM)2(H2O)2](ClO4)2 · H2O. This compound crystallizes in the orthorhombic system, P212121 space group, Z = 4 with a = 8.749(1) Å, b = 14.213(1) Å, c = 21.200(2) Å, and V = 2636.2(4) Å3. The metal ion is surrounded in octahedral geometry by two mutually quasi-perpendicular N5,O4-coordinated lumazine chelators with the O4 atoms trans and the N5 atoms cis. The polyhedron is completed by two cis-coordinated water molecules. The absolute configuration of the complex can be described, following Bailar's nomenclature, as the enantiomer Λ of the stereoisomer 4M. A three-dimensional hydrogen-bond network is defined by water molecules, perchlorate anions, and the O2 of the pteridine A.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009548803103
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  • 9
    Digitale Medien
    Digitale Medien
    Synthesis and characterization of the dodecanuclear heterobimetallic Mo—Cu—S cage cluster: (Ph4P)2[{Mo2Cu2O2S2(S2)2}3(μ6-S)] (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 581-586 
    Details
    ISSN: 1572-8854
    Schlagwort(e): dodecanuclear heterobimetallic ; molybdenum-copper cluster ; cage ; μ6-S ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The complex (Ph4P)2[Mo2S2O2(S2)(S4)] reacts with CuBr to give the dodecanuclear heterobimetallic Mo—Cu—S cage cluster: (Ph4P)2[{Mo2Cu2O2S2(S2)2}3(μ6-S)] (1), which crystallizes in the triclinic space group P1¯, a = 14.445(5), b = 15.396(5), c = 18.858(5) Å, α = 103.12(3), β = 101.93(2), γ = 113.92(3)°, and V = 3517(2) Å3 for Z = 2. The anion 1 can be described as a cage with S2− at the center binding to six Cu atoms; the cage has two big windows each composed of a puckered Cu3S6 9-membered ring.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009552904012
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  • 10
    Digitale Medien
    Digitale Medien
    Crystal and molecular structure of five coordinate copper(II) complex with 2,6-bis[1-(methoxycarbonylmethyl–hydrazono)ethyl] pyridine (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 575-580 
    Details
    ISSN: 1572-8854
    Schlagwort(e): copper(II) complexes ; 2,6-diacetylpyridine derivative ; open-chain ligand ; crystal structure ; trigonal-bipyramidal geometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title compound was obtained by a template synthesis from 2,6-diacetylpyridine, ethylhydrazinoacetate and CuCl2·2H2O (molar ratio 1:2:1, in methanol), and its structure has been determined by single-crystal X-ray diffraction: monoclinic space group P21/c, a = 13.906(5), b = 18.199(6), c = 16.641(6) Å, β = 107.18(3)°, and z = 4. The ligand was found to be tridentate in a trigonal-bipyramidal coordination geometry with two chloride ligands. There are two independent complex molecules, one of which is hydrogen bonded to the water of crystallization.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009500919942
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  • 11
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of the heterometallic square-chain polythiometalate: {[W4Ag5S16]2 · [La(DEF)2(DMF)6][La(DEF)4(DMF)4]}n (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 629-633 
    Details
    ISSN: 1572-8854
    Schlagwort(e): heterometallic polymeric cluster ; polythiometalate ; synthesis ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The complex (NH4)2 WS4 reacts with AgNO3 and La(NO3)3 · 6H2O in a mixture of DEF/DMF (DEF—N,N′-diethylformamide), to give a new heterometallic square-chain polythiometalate {[W4Ag5S16]2 · [La(DEF)2(DMF)6] · [La(DEF)4(DMF)4]}n (1). 1 crystallizes in the monoclinic space group P2/c, a = 19.5534(8), b = 16.9552(6), c = 22.3479(9) Å, β = 106.053(1)°, V = 7120.1(5) Å3, and Z = 2. The anion polymeric chain of 1 can be regarded as an octanuclear cyclic cluster of [W4Ag4S16]4− fragments linked through Ag+ ions. The polymeric chain is extended through the parallel edges of the square unit. The mean W—Ag distance is 2.963(16) Å. The La3+ cations are coordinated by different solvent molecules, the average La—O bond of these large trivalent cations is 2.47(1) Å.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009517423576
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  • 12
    Digitale Medien
    Digitale Medien
    Absolute configuration of C23H34O8Si, the product of an asymmetric synthesis involving the Rh(II) catalyzed reaction of a chiral vinyldiazomethane with methyl-2-methyl-3-furoate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 707-711 
    Details
    ISSN: 1572-8854
    Schlagwort(e): oxabicyclo[3.2.1]octadiene ; absolute configuration ; asymmetric synthesis ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The compound under investigation crystallizes in the noncentrosymmetric orthorhombic space group P212121 with a = 7.9358(11), b = 11.0532(13), c = 29.2425(43) Å, volume = 2565.0(6) Å3, and Z = 4. The C23H34O8Si molecule contains three chiral centers (one of which is of known configuration, based upon an (R)-pantolactone auxillary group). We have determined the absolute configuration of this species (via the anomalous dispersion of Si relative to C and O) and show that it is consistent with the known configuration of the (R)-pantolactone moiety.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009532106081
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  • 13
    Digitale Medien
    Digitale Medien
    Absolute configuration of C20H30O6Si, a species with a (1R,5R)-8-oxabicyclo[3.2.1]octa-2,6-diene core produced selectivity by the rhodium(II) octanoate catalyzed decomposition of a chiral vinyldiazomethane in the presence of furan (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 713-717 
    Details
    ISSN: 1572-8854
    Schlagwort(e): oxabicyclo[3.2.1]octadiene ; absolute configuration ; asymmetric synthesis ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The compound under investigation crystallizes in the noncentrosymmetric monoclinic space group P21 with a = 9.1798(23), b = 6.6606(18), c = 17.6591(41) Å, β = 94.342(20)° and Z = 2. The C20H30O6Si molecule contains three chiral centers (one of which is of known configuration, based upon an (R)-pantolactone auxiliary group). We have determined the absolute configuration of this species (via the anomalous dispersion of Si relative to C and O) and show that it is consistent with the known configuration of the (R)-pantolactone moiety
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009584122919
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  • 14
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of 1,1′-di(ethylpropionato)-2,2′-biimidazole, a macromolecular precursor (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 765-768 
    Details
    ISSN: 1572-8854
    Schlagwort(e): 2,2′-biimidazole ; diester ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract 1,1,′-Di(ethylpropionato)-2,2′-biimidazole, C16H22N4O4, crystallizes from ice-cold ethanol in the space group P $$\bar 1$$ , with a = 4.6742(9), b = 9.1119(13), c = 10.175(2) Å, α = 96.22(1), β = 96.29(2), γ = 97.53(1)°, and Z = 1. The molecule crystallizes with coplanar rings and the substituents assume a trans conformation with a center of inversion between the bridging carbon atoms.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009535501461
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  • 15
    Digitale Medien
    Digitale Medien
    The crystal and molecular structure of mercury(II) bis(isopropyl)dithiophosphate, Hg[S2P(OPri)2]2, revisited: new comments about its supramolecular self-organization (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 831-836 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Hg coordination ; crystal structure ; organomercury derivatives
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal structure of the title compound, Hg[S2P(OPri)2]2, has been determined by single-crystal X-ray diffraction. The compound crystallizes in the centrosymmetric P21/c space group with a = 11.800(1), b = 8.925(2), c = 22.167(2) Å, β = 94.988(7)°, and Z = 4. The same compound has been previously reported but the structure is described there in the space group C2/c. In both cases, one phosphorodithioate moiety acts as a chelating group and the other as a bridging group between neighboring mercury atoms (related to one another by the twofold screw axis), giving rise to an infinite polymer along the direction of the b axis. It turns out that in spite of the difference in space group symmetry, the structures are remarkable similar in that they are formed from infinite polymers of similar geometry. The coordination around the Hg ion shows, however, significant differences, mainly for the bridging Hg—S(4) bond length, which is 0.16 Å smaller than that previously reported.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009508122842
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  • 16
    Digitale Medien
    Digitale Medien
    Generation and intermolecular trapping of a cage-annulated cycloalkylidenecarbene (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 329-333 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Carbene ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Base-promoted reaction of 11-methylenepentacyclo[5.4.0.02,6.03,10.05, 9]undecan-8-one (5) with diethyl diazomethylphosphonate when performed in the presence of excess cyclohexene, resulted in the formation of the corresponding cycloalkylidenecarbene, 6, which subsequently was trapped in situ to afford 8-methylene-11-(7′-bicyclo[4.1.0]heptylidene)pentacyclo-[5.4.0.02, 6.03, 10.05, 9]undecane (7, obtained in 44% yield as a mixture of exo, endo isomers). Subsequent reaction of 7 with dichlorocarbene (generated under phase transfer catalytic conditions) produced the corresponding mono- and di-:CCl2 adducts [i.e., 8 (64% yield) and 9 (5% yield), respectively]. The structure of 9 was established unequivocally via application of single crystal X-ray analysis: Triclinic, P1¯, a = 6.276(2), b = 8.700(2), c = 18.550(3) Å, α = 76.52(3), β = 87.59(3), γ = 70.88(4)° Z = 2; D calc 1.486 g cm−3.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009530019690
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  • 17
    Digitale Medien
    Digitale Medien
    Crystal structure of the addition compound of N,N′-bi(2-pyridylmethyl)-oxamide and complex of manganese with 1,10-phenanthroline (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 623-627 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; manganese complex ; disubsituted oxamide ; addition compound
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The structure of the addition compound, Mn(phen)3(PMoxdH2)(ClO4)2 was established by X-ray crystallography, where PMoxdH2 is N,N′-bi(2-pyridylmethyl)-oxamide. Six nitrogen atoms of the three 1,10-phenanthroline bind to the manganese ion and the oxygen atom of PMoxdH2 is uncoordinated. The addition compound crystallizes in the monoclinic space group C2/c, with lattice parameters a = 23.780(6), b = 11.948(5), c = 18.466(6) Å, β = 117.38(3)°, V = 4659(3) Å3, and Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009565306738
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  • 18
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structures of two potential gem-di(pyrazolyl)cycloalkane ligands, 1,1-di(pyrazol-1-yl)cyclohexane [C6H10(C3N2H3)2] and 1,1-di(pyrazol-1-yl)cyclopentane [C5H8(C3N2H3)2] (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 659-665 
    Details
    ISSN: 1572-8854
    Schlagwort(e): pyrazolyl derivative ; substituted cyclopentane ; substituted cyclohexane ; crystal structure ; bidentate ligand
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The species 1,1-di(pyrazol-1-yl)cyclohexane, C12H16N4, crystallizes in the monoclinic space group P21/c with a = 8.340(2), b = 14.281(5), c = 10.153(3) Å, β = 106.86(2)°, and Z = 4. The cyclohexane moiety has the chair conformation. The congener, 1,1-di(pyrazol-1-yl)cyclopentane, C11H14N4, while not isomorphous, also crystallizes in space group P21/c with a = 14.350(2), b = 6.776(1), c = 11.043(2) Å, β = 100.68(1)°, and Z = 4. The cyclopentane ring has a conformation in which four carbon atoms are essentially coplanar, while the fifth (that with the two pyrazolyl substituents) lies 0.63 Å from this plane, resulting in a bend of 41.3° across the C(2)···C(5) vector. The hydrogen atoms in each structure were located directly and their coordinates refined.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009515602446
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  • 19
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of 4,5-(cis-cyclohexylenedithio)-1,3-dithiole-2-one (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 719-723 
    Details
    ISSN: 1572-8854
    Schlagwort(e): synthesis ; crystal structure ; independent molecules
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The x-ray crystal structure of 4,5-(cis-cyclohexylenedithio)-1,3-dithiole-2-one has been determined. Yellow block shaped crystals of C9H10OS4 crystallize in the space group P $${\bar 1}$$ with cell dimensions a = 8.872(4), b = 9.330(8), c = 14.333(12) Å, α = 95.23(7), β = 91.09(5), γ = 107.60(5)°, V = 1124.8(14) Å3, and Z = 4. This compound has two S---S contacts [3.574, 3.610 Å] shorter than 3.70 Å and the usual disordered ethylene moiety [C(3)—C(8)] of the six-membered ring is fixed by the cis-cyclohexylene subsitituent. This means that it may be a new precursor for conducting and strong near-IR absorbing nickel-dithiolenes. Also, it provides the first example of polymorphism of the dmit derivatives and contains two independent molecules I and II in the asymmetric unit.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009536206989
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  • 20
    Digitale Medien
    Digitale Medien
    The crystal and molecular structure of 2-S-methylthiouracil (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 725-727 
    Details
    ISSN: 1572-8854
    Schlagwort(e): 2-thiouracil derivatives ; crystal structure ; S-methyl-thiouracil ; hydrogen bonding ; structural methylation and metallation effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract 2-S-Methylthiouracil crystallizes in the triclinic space group P $${\bar 1}$$ with unit cell dimensions a = 5.508(4), b = 7.175(3), c = 8.522(2) Å, α = 80.83(2), β = 80.43(3), γ = 76.86(3)°, and Z = 2. The molecule exists in the crystal in the lactam form and is essentially planar. The molecular packing consists of molecules linked in centrosymmetric hydrogen-bonded pairs. The effects of methylation and subsequent metallation on the 2-thiouracil structure are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009588223827
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  • 21
    Digitale Medien
    Digitale Medien
    Crystal structure and emission study of [(PPh3)2Cu(dmp)-O-(dmp)Cu(PPh3)2]2+ (dmp = 2,9-dimethyl-1,10-phenanthroline) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 797-802 
    Details
    ISSN: 1572-8854
    Schlagwort(e): synthesis ; crystal structure ; Cu(I) complex ; μ-oxo-bis(2,9-dimethyl-1,10-phenanthroline) ; luminescence
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The synthesis and crystal structure of a luminescent dinuclear Cu(I) complex as the BF− 4 salt from toluene and methanol containing triphenylphosphine and μ-oxo-bis(2,9-dimethyl-1,10-phenanthroline) is described. The coordination geometry about the Cu(I) center is distorted tetrahedral. An unusual feature of the structure is a pseudo-inversion center located near the oxygen atom at approximately 0.51, 0.26, 0.25, such that all of the atoms except for the oxygen are related by a pseudo-inversion center to another atom in the same molecule, as well as by crystallographic inversion to the other molecule in the unit cell. The complex displays luminescence from an MLCT band in fluid solution and emission from both a metal-centered charge-transfer and intraligand (phenanthroline) state at 77K in a chloroform snow. Crystal data: triclinic, P $$\bar 1$$ , a = 15.163(2), b = 16.985(2), c = 18.731(2) Å, α = 106.458(9), β = 91.416(8), γ = 102.557(9)°, V = 4496(1) Å3, and Z = 2.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009595720117
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  • 22
    Digitale Medien
    Digitale Medien
    Structural analysis of tris(tetra-n-butylammonium) hexakisisothiocyanatoyttrate(III) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 729-733 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; yttrium complexes ; isothiocyanate complexes ; octahedral coordination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The structural analysis of [(n-C4H9)4N]3[Y(NCS)6] (I) using single-crystal diffraction data and full-matrix least squares refinement has been carried out. The hexaisothiocyanate complex crystallizes in the centrosymmetric triclinic space group P $${\bar 1}$$ (No. 2) with unit cell constants of a = 12.431(1), b = 12.866(1), c = 22.750(2) Å, α = 90.78(1), β = 92.05(1), γ = 96.67(1)°, and Z = 2. The molecular unit consists of three separate cationic tetra-n-butylammonium groups and an independent hexakisisothiocyanatoyttrate anionic group in which the six thiocyanate ligands are octahedrally coordinated through the N atom to the Y central ion. Selected bond distances and angles are presented as well as the synthesis and peripheral studies of (I).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009540307898
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  • 23
    Digitale Medien
    Digitale Medien
    Synthesis and structure of bis(dibenzoylmethane)copper(II) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 793-796 
    Details
    ISSN: 1572-8854
    Schlagwort(e): copper complex ; crystal structure ; dibenzoylmethane complex
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Bis(dibenzoylmethane)copper Cu(dbm)2 has been synthesized and its structure determined by x-ray diffraction. It crystallizes in the monoclinic system, space group C2/c, with a = 25.936(3), b = 5.9806(8), c = 16.4908(16) Å, β = 114.998(8)°, Z = 4, and V = 2318.3(4) Å3. The Cu atom is located at a symmetry center and surrounded by four O atoms from two dbm molecules to form a plane square coordination environment. On the a–c plane the molecules are orderly arranged to result in a layered structure, and parallel to crystallographic b-axis they form a molecular column due to the effect of aromatic stacking.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009543703278
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  • 24
    Digitale Medien
    Digitale Medien
    Crystal structure of [WBr2(CO)(PPh2Cy)2(η2-MeC2Me)]·CH2Cl2 (Cy = cyclohexyl) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 809-812 
    Details
    ISSN: 1572-8854
    Schlagwort(e): tungsten(II) ; dibromo ; carbonyl ; diphenylcyclohexylphosphine ; but-2-yne ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract [WBr2(Co)(PPh2Cy)2(η2-MeC2Me)]·CH2Cl2 (Cy = cyclohexyl) crystallizes in the monoclinic space group, P21/n, with a = 10.606(12), b = 23.11(3), c = 18.19(2) Å, β = 106.070(10) Dcalc = 1.610g cm−3 for Z = 4. The tungsten coordination geometry can best be considered as a distorted octahedron, with the but-2-yne ligand occupying one coordination site, which has a trans-Br(2) group. The equatorial plane is made up of trans-PPh2Cy groups, with the bromo and carbonyl ligands occupying the other two sites.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009599821025
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  • 25
    Digitale Medien
    Digitale Medien
    1-(Ethoxymethyl)-6-(phenylselenyl)-5-ethyl uracil: a nucleoside analog (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 837-839 
    Details
    ISSN: 1572-8854
    Schlagwort(e): acyclonucleoside analog ; 6-(phenyl selenyl) uracil derivative ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The compound, 1-(ethoxymethyl)-6-(phenylselenyl)-5-ethyl uracil, crystallizes in the monoclinic space group P21/n with unit cell parameters a = 5.304(1), b = 21.261(4), c = 13.996(4) Å, β = 94.30(2)°, and Z = 4. The acyclic chain C1′, O4′, C4′, C5′ is in fully extended form and nearly perpendicular to the uracil base. The molecules are held together by van der Waal's forces.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009560106913
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  • 26
    Digitale Medien
    Digitale Medien
    Mercury(II) halide complexes with N-donor organic ligands: crystal and molecular structure of HgI2R, R = 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline, bipyridine (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 825-830 
    Details
    ISSN: 1572-8854
    Schlagwort(e): mercury halides ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The synthesis, characterization and single crystal X-ray structure of three compounds of general formula HgI2R (R = phen[1], dmph [2] and bpy[3]) are presented. The crystal data for the three compounds are: [1], triclinic, space group P $$\bar 1$$ (#2) a = 7.902(2), b = 9.479(2), c = 10.002(2) Å, α = 91.45(2), β = 111.34(2), γ = 100.82(2)° [2]: monoclinic, space group C2/c (#15) a = 15.670(3), b = 11.640(2), c = 9.730(2) Å, β = 114.57(3)° [3]: triclinic, space group P1¯ (#2) a = 9.472(1), b = 9.507(1), c = 9.023(1) Å, α = 98.46(1), β = 102.89(1), γ = 119.62(1)°. Compounds [1] and [2] are monomers, with highly distorted tetrahedral environments around Hg. In [3], instead, there is a significant intermolecular I···Hg interaction leading to the formation of softly bound dimers linking two pentacoordinated cations. The structure is compared with related ones in the literature.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009556006004
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  • 27
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of [WI(CO)(cis-dppen) η2-MeC2Me)2]I·CH2Cl2 {cis-dppen = bis(diphenylphosphino)ethene} (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 907-911 
    Details
    ISSN: 1572-8854
    Schlagwort(e): tungsten(II) ; Iodo ; carbonyl ; cis-bis(diphenylphosphino)ethene ; but-2-yne ; cationic ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The complex [WI(CO)(cis-dppen)(η2-MeC2Me)2]I·CH2Cl2(1) is prepared as a by-product from the reaction of equimolar quantities of [WI2(CO)(NCMe)(η2-MeC2Me)2] and cisdppen {dppen = bis(diphenylphosphino)ethene}. Complex 1, [WI(CO)(cis-dppen)(η2-MeC2Me)2]I·CH2Cl2 crystallizes in the triclinic space group $${\text{P}}\bar 1$$ with a = 11.189(13), b = 12.331(14), c = 15.395(17) Å, α = 83.61(1), β = 86.06(1), γ = 64.48(1)°, U = 1904 Å3, and Z = 2. The metal environment in the cation can best be considered as a distorted octahedron with the two but-2-yne groups taking up individual sites trans to phosphorus atoms of the dppen ligand. The coordination sphere is completed by mutually trans-carbonyl and iodide groups.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009526012075
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  • 28
    Digitale Medien
    Digitale Medien
    4-(1,4-Dimethoxy-2-naphthyl)-4- hydroxycyclohexanone and its ethylene ketal (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 955-959 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; intramolecular hydrogen bond ; 4-(1,4-dimethoxy-2-naphthyl)-4-hydroxycyclohexanone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Intramolecular hydrogen bonding in the solid state is reported for the title compound and its ethylene ketal. The title compound crystallizes in the triclinic space group, $$P\bar 1$$ with a = 9.590(3), b = 9.620(3), c = 9.844(2) Å, α = 97.67(2), β = 105.25(2), γ = 115.47(2), and Z = 2. The ethylene ketal crystallizes in the monoclinic space group, P21/c, with a = 7.230(2), b = 22.639(3), c = 10.839(2) Å, β = 101.47(2), and Z = 4. The intramolecular hydrogen bond length of 1.79 Å is the same for the ketone and ketal, but the O—H---O valence angle is 144° for the ketone and 165° for the ketal.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009538414801
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  • 29
    Digitale Medien
    Digitale Medien
    Crystal structure and physical characterization of neotame methanol solvate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 967-975 
    Details
    ISSN: 1572-8854
    Schlagwort(e): neotame ; crystal structure ; methanol solvate ; thermal analysis ; powder X-ray diffractometry ; 13C solid-state nuclear magnetic resonance spectroscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal structure of the methanol solvate (empirical formula: 2C20H30N2O5·3CH3OH) of a new dipeptide sweetener, neotame (N-(3,3-dimethylbutyl)-L-α-aspartyl-L-phenylalanine 1-methyl ester), has been determined. Crystal data: a = 9.8989(1), b = 18.1331(1), c = 27.5725(1) Å, orthorhombic, space group P212121, with Z = 4. Each unit cell includes 8 neotame and 12 methanol molecules. Disorder exists in one neotame molecule and one methanol molecule. The crystals were characterized by the following techniques: hot-stage microscopy (HSM), Karl-Fischer titrimetry (KFT), powder X-ray diffractometry (PXRD), differential scanning calorimetry (DSC), thermogravimetry (TGA), 13C solid-state nuclear magnetic resonance (SSNMR) spectroscopy. Under HSM at a heating rate of 10°C/min in silicone oil, the sample melts at 64–84°C and liberates bubbles at 71–86°C. DSC in open pans shows two overlapping endotherms at 56 and 71°C, probably due to melting and desolvation, respectively. TGA in open pans shows 5.9% weight loss due to desolvation below 70°C. Under house vacuum (23 mm Hg) over phosphorus pentoxide at 23°C, the methanol solvate produces pure amorphous anhydrate, which converts to crystalline neotame monohydrate in the presence of moisture.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009542515709
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  • 30
    Digitale Medien
    Digitale Medien
    A study of two geometric isomers of 1,1′-bi-3-cyanocyclohex-2-enylidene (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 977-982 
    Details
    ISSN: 1572-8854
    Schlagwort(e): cyano allyl radical ; thermal arrangement ; crystal structure ; isomer ; NMR, MM2
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The preparation, separation, crystal structure and 1H NMR spectra are reported for the two geometrical isomers of 1,1′-bi-3-cyanocyclohex-2-enylidene. The E-isomer crystallized as thin plates in the monoclinic space group P21/n with a = 5.3980(5), b = 7.0757(7), c = 15.300(2) Å, β = 94.571(2)°, and Z = 2. The structure has symmetry C2h. The Z-isomer crystallized as needles in the triclinic space group P1¯ with a = 7.0790(6), b = 11.3155(9),c = 15.386(1) Å, α = 104.943° β = 90.164(2)°, γ = 99.494(2)°, and Z = 4. The compound crystallized with two molecules per asymmetric unit. In C6D6, 1H NMR signals of the 2-vinyl protons appear almost identical. However, in a mixture of C6D6 and pyridine-d 5, the 2-vinyl protons can be distinguished. The structures compare favorably with MM2 calculations.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009594532547
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  • 31
    Digitale Medien
    Digitale Medien
    X-ray crystal structure of tetraaquabis (xanthosinato)nickel(II) hexahydrate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1009-1013 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; nickel complex ; xanthosine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The complex [Ni(XsH−1)2(H2O)4]·6H2O (XsH−1: xanthosinate) was isolated from the reaction of nickel carbonate with xanthosine in aqueous solution. The octahedral coordination is supported by the reflectance measurements. Single-crystal X-ray diffraction studies show that the crystals belong to the triclinic P1 space group, with a = 7.152(1), b = 8.830(1),c = 13.783(1) Å, α = 82.024(1)°, β = 86.155(1)°, γ = 70.900(1)°, and D = 1.643 mg/m3, forZ = 1. Nickel is six coordinate with four water molecules, and two N7 atoms from xanthosinato ligands. A complicated hydrogen-bonding network is present, all possible donors taking part in it.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009568616134
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  • 32
    Digitale Medien
    Digitale Medien
    Reactions of [Mn2(μ-pyS)2(CO)6] (pySH=pyridine-2-thiol) with triphenylphosphine (PPh3), diphenylphosphine (PHPh2) and bis(diphenylphosphino)methane (dppm): X-ray crystal structure of [Mn(pyS)(η1-dppm)2(CO)2] (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1001-1007 
    Details
    ISSN: 1572-8854
    Schlagwort(e): manganese ; pyridine-2-thiolate ; bis(diphenylphosphino)methane ; carbonyl ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The dimeric complex [Mn2(μ-pyS)2(CO)6] (1) reacted with 2 M equivalents of both PPh3 and PHPh2 to give the respective monomeric phosphine complexes [Mn(pyS)(L)(CO)3][L = PPh3 (2) and PHPh2 (3)]; with 4 M equivalents of dppm, it yielded the complex [Mn(pyS)(η1-dppm)2(CO)2](4). An X-ray structure determination of 4 shows that it crystallizes in the monoclinic space group P21/n with a = 11.027(3), b = 24.984(7), c = 18.379(5) Å, β = 99.870(8)°, V = 4988(2) Å3, and Z = 4. The complex has an octahedral geometry with the chelating pyS ligand and two CO groups occupying the equatorial sites and the two monodentate dppm ligands lying in the trans positions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009516632064
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  • 33
    Digitale Medien
    Digitale Medien
    Crystal structure of 1,3-di-2-[(4-methoxyphenyl)-1-diazenyl]imidazolidine (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1037-1041 
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    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; imidazolidine ; triazene ; bis-triazene ; methoxy substituent ; π-π stacking
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal and molecular structure of 1,3-di-2-[(4-methoxyphenyl)-1-diazenyl]imidazolidine (1) has been determined by single crystal X-ray diffraction analysis. This novel bis-triazene assumes a close-to planar structure with the aryltriazene moieties aligned in diametrically opposed directions, unlike many other previously reported bis-triazenes, which assume a folded structure. The structure of 1 is compared with the closely related, non-cyclic bis-triazene analogue (2), and also compared with the structure of the simple mono-triazene (3). Crystal data: 1 C17H20N6O2, monoclinic, space group C2/c, a = 34.948(3), b = 5.925(5), c = 8.1225(6) Å, β = 100.8420(10)°, and V = 1652.0(2) Å3, for Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009529002022
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  • 34
    Digitale Medien
    Digitale Medien
    Crystal structure of 2-{(R)-1-hydroxy-1-[(2S)-1-tritylaziridin-2-yl] methyl}acrylate and spectroscopic properties of the (R,S) and (S,S) stereoisomers (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1053-1056 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; tritylaziridine ; acrylate ; spectroscopic features
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal and molecular structure of 2-{(R)-1-Hydroxy-1-[(2S)-1-tritylaziridin-2-y1] methy1}acrylate is described. Crystal data: C26H25NO3, orthorhombic, space group P212121, a = 9.6954(5), b = 13.1458(5), c = 16.7885(7) Å, V = 2139.8(2) Å3, Z = 4. The (R,S) diastereomer shows an intramolecular hydrogen bonding N···H—O under formation of a five-membered ring with N···O distance of 2.664 Å. IR, 1H NMR and 13C NMR data are discussed. The 1H NMR of the (R,S) diastereomer shows a singlet- whereas the (S,S) diastereomer exhibits a doublet-pattern for the hydroxyl proton.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009585119769
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  • 35
    Digitale Medien
    Digitale Medien
    Absolute configuration of C27H41NO8Si, the diastereoselective product of the rhodium(II) octanoate catalyzed decomposition of a chiral vinyldiazomethane in the presence of 2-acetylpyrrole: A structural study rendered difficult by disorder of a “heavy” atom (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1061-1066 
    Details
    ISSN: 1572-8854
    Schlagwort(e): absolute configuration ; asymmetric synthesis ; azabicyclo[3.2.1]octadiene ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title compound crystallized in space group P21 with a = 12.647(8), b = 14.542(4), c = 17.077(16) Å, β = 97.51(6)°, and D calc = 1.143 mg/m3 for Z = 4. There are two chemically-equivalent C27H41NO8Si molecules in the crystallographic asymmetric unit. Each contains three chiral centers, one of known absolute configuration based upon the (R)-pantolactone,—CH*—CMe2—CH2—O—CO—, moiety. The structural study was greatly complicated by disorder of an —OSiMe2(t-Bu) group in one molecule.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009589220678
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  • 36
    Digitale Medien
    Digitale Medien
    Crystal structure of [Co(bipy)(maleato) (H2O)3]·H2O (bipy = 2,2′-bipyridine) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1081-1084 
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    ISSN: 1572-8854
    Schlagwort(e): cobalt(II) ; bipyridine ; maleato ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Preparation of the mononuclear cobalt(II) complex, [Co(bipy)(maleato) (H2O)3]·H2O (1) where bipy = 2,2′-bipyridine, were accomplished by reaction of an aqueous solution containing sodium maleate and an ethanolic solution of Co(NO3)2·6H2O and bipy. The crystal structure of complex (1) was determined by X-ray crystallography. The complex crystallizes in the monoclinic space group P21/n with a = 9.477(3), b = 7.660(2), c =23.526 (3) Å, β = 97.64(2)°, V = 1692.6(6) Å3, and Z = 4. The structure consists of discrete mononuclear cobalt molecules. The cobalt atom is six-coordinate and presents a slightly distorted octahedral geometry, which consists of the two imine N atoms of bipy, a terminal carboxylate O atom from maleato ligand, and a water O atom in the basal plane with Co—N bond distances of 2.116(2) and 2.124(3) Å and Co—O distances of 2.075(2) and 2.088(2) Å, respectively. The relatively shorter Co—O distances are due to the trans effect of the bipy ligand. The octahedral coordination is completed the other two water molecules. The coordinate and the lattice water molecules were identified by TG study.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009597422495
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  • 37
    Digitale Medien
    Digitale Medien
    Crystal and molecular structure determination, TGA, DTA, and infrared and Raman spectra of rubidium nitroprusside monohydrate, Rb2[Fe(CN)5NO]·H2O (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 75-80 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Rubidium nitroprusside monohydrate ; crystal structure ; properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal structure of rubidium nitroprusside monohydrate, Rb2[Fe(CN)5NO] · H2O, has been determined from X-ray diffraction data and refined using direct and Fourier methods to R = 0.066 and Rw = 0.075, employing 1894 independent reflections with I 〉 3 (I). The substance crystallizes in the monoclinic space group C2/c (C 6 2h), with a = 13.987(2), b = 10.241(1), c = 18.151(1) Å, β = 110.94°, and Z = 8. Anions are located at C 1 sites, one per asymmetric unit, and are slightly distorted octahedra. TGA, DTA, FTIR, and FTIR Raman results were interpreted on the basis of the formula of the compound, its crystal structure, and the behavior of other nitroprussides.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009575415668
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  • 38
    Digitale Medien
    Digitale Medien
    Crystal structure of methyl trans-3-[(2-(methoxycarbonyl)phenyl)sulfinyl]acrylate: a product resulting from trapping of a sulfenic acid by methyl propiolate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1133-1136 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; methyl propiolate ; sulfenic acid ; vinyl sulfoxide ; leinamycin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Evidence for the formation of unstable sulfenic acids (RSOH) as reaction intermediates is commonly provided by trapping these compounds with methyl propiolate. The crystal structure of a vinyl sulfoxide derived from the trapping of a sulfenic acid with methyl propiolate is reported here. The title compound C12H12O5S crystallized in the triclinic space group,P1¯ with unit cell parameters: a = 6.1600(4), b = 9.7286(7), c = 11.3698(8) Å, α = 112.024(1), β = 94.662(1), γ = 95.429(1)°, and Z = 2.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009518127038
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  • 39
    Digitale Medien
    Digitale Medien
    9[1-(2-Hydroxy ethoxy)-3-hydroxy propyl] guanine: a nucleoside analog (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1137-1139 
    Details
    ISSN: 1572-8854
    Schlagwort(e): acyclic nucleoside analog ; acyclovir ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The compound 9[1-(2-hydroxy ethoxy)-3-hydroxy propyl] guanine crystalizes in the tetragonal system, space group P41212 with a = 11.106 (1), c = 20.558 (2) Å, and Z = 8. The acyclic chain C1′¯O1′¯C4′¯C5′¯O5′ is in the extended configuration and the glycosidic torsion angle (C4¯N9¯C1′¯O1′) is 125.1 (8)°. The molecules are held together by Van der Waal's forces.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009570111108
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  • 40
    Digitale Medien
    Digitale Medien
    Structure, thermal behavior, and IR investigation of a new organic sulfate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1205-1210 
    Details
    ISSN: 1572-8854
    Schlagwort(e): organic sulfate ; crystal structure ; DTA/TG/DSC ; vibrational spectra
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract [1-(2-ammoniumethyl) piperazinium] sulfate denoted PIPS has a monoclinic unit cell. The parameters are: a = 6.6521(3), b = 7.8756(5), c = 19.197(1) Å, β = 94.43(1)° and the space group is P21/n. The preparation, thermal analysis, and IR spectrometric investigation are described. The PIPS structure exhibits a complex three-dimensional network of H-bonds connecting all its components.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009559718165
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  • 41
    Digitale Medien
    Digitale Medien
    Structure of de-oxy corticosterone-21-hemisuccinate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1265-1269 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; corticosteroid ; de-oxy corticosterone-21-hemisuccinate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Synthetic glucocorticoid de-oxy corticosterone-21-hemisuccinate crystallizes in the monoclinic space group C2, with a = 21.896(2), b = 7.596(3) and c = 14.291(3) Å, Z = 4. Ring A is a distorted half chair, ring B and C are in the chair configuration and ring D is in the 14α-half chair configuration. The ring junctions B/C and C/D are both trans. The molecule as a whole is slightly convex towards the β-side, with an angle of 18.4(2)° between the C(10)--C(19) and C(13)--C(18) vectors. In addition to packing and stacking interaction, intermolecular hydrogen bonding plays an important role in structural association. The X-ray structure determination of the title compound was undertaken to study its high binding affinity to serum protein like globulin.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009504923424
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  • 42
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of 1-phenyl-3-methylthio-4-imino-5-allyl-pyrazolo[3,4-d]pyrimidine (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1291-1293 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; pyrazolo[3,4-d]pyrimidine ; fungicidal activity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title compound 1-phenyl-3-methylthio-4-imino-5-allyl-pyrazolo[3,4-d]pyrimidine, C15H15N5S, has been synthesized and characterized by x-ray diffraction: orthorhombic, space group Pbca, with a = 17.3480(9), b = 8.5022(5), c = 19.8132(11) Å. Z = 8, V = 2922.4(3) Å3. The compound shows a fully delocalized pyrazolo[3,4-d]pyrimidine system with a sp2 hybridization of the N(4) atom.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009565209312
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  • 43
    Digitale Medien
    Digitale Medien
    Crystal structure of [Mn(II)(phen)(ClCH2COO)2]n (phen = 1,10−phenanthroline) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 199-201 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Manganese (II) ; phenanthroline ; polymeric complex ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract A new polymeric manganese(II) complex, [Mn(II)(phen)(ClCH2COO)2]n, was obtained from the reaction of Mn(ClCH2COO)2 with phen and its structure was determined by x-ray crystallography. The complex crystallizes in the monoclinic system, space group C2/c with a = 19.706(4), b = 11.381(3), c = 7.482(3) Å, β = 94.01(3)°, V = 1674.0(8) Å3, and Z = 4. The structure consists of an infinite chain. The manganese atom is located on a twofold axis and presents a distorted octahedral coordination sphere, which consists of the two N atoms of a phen ligand (Mn—N = 2.304(2) Å) and four carboxylato ligands. The Mn···Mn distance within the chain is 4.53 Å, and the carboxylato bridges present a syn-anti conformation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009574128099
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  • 44
    Digitale Medien
    Digitale Medien
    Synthesis of a new dibenzo-14-crown-4 lariat ether and structure of its sodium perrhenate complex (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1255-1259 
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    ISSN: 1572-8854
    Schlagwort(e): crown ether ; crystal structure ; lariat ; sodium
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract A dibenzo-14-crown-4 ether with a novel monooxyacetone sidearm is prepared and its structure with sodium perrhenate is determined. The structure crystallizes in P21/c with cell dimensions: a = 8.107(2) Å, b = 28.138(3) Å, c = 10.293(2) Å, and β = 104.173(9)°; giving a volume of 2276.6(7) Å3. This structure is compared to other sodium complexes of dibenzo-14-crown-4 lariat ethers and is found to be the only one with intramolecular bonding between the sidearm and the cation. Possible reasons for this observation are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009552806586
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  • 45
    Digitale Medien
    Digitale Medien
    Structure of de-oxy corticosterone (4-pregnen-21-ol-3,20-dione) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1271-1275 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; pregnen ; progestin ; 4-pregnen-21-ol-3,20-dione
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Synthetic steroid de-oxy corticosterone (4-pregnen-21-ol-3,20-dione) crystallizes in the monoclinic space group P21, with a = 11.706(2); b = 11.171(3), c = 13.966(3) Å, and β = 100.94(2)°, Z = 4. Ring A tends to acquire the conformation of a half-boat, rings B and C are in the chair configuration, and ring D is a 13β, 14α-half-chair. The ring junctions B/C and C/D are both trans, whereas the ring junction A/B is quasi-trans. The molecule as a whole is slightly convex toward the β-side, with an angle of 16.01(0.36)° between the C10--C19 and C13--C18 vectors. Molecular packing and stacking interactions play the major role in structural association. Cohesion of the crystal is due to van der Waals interactions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009556907495
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  • 46
    Digitale Medien
    Digitale Medien
    Polymeric copper(II)-orotato complexes, [(C5H2N2O4)Cu(H2O)2]n (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 565-569 
    Details
    ISSN: 1572-8854
    Schlagwort(e): orotic acid complex ; crystal structure ; copper(II) complex
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The compound [(C5H2N2O4)Cu(H2O)2]n has been synthesized and its structure determined at room temperature. The primary coordination sphere at the Cu ion is square planar with the orotate dianion coordinating at the metal through heterocyclic nitrogen atom and adjacent oxygen of the carboxylate group, the remaining coordination sites are occupied by two water molecules. The orotate dianion is tricoordinated to one copper via N1 and one oxygen of the carboxylato group and to another copper atom via the other oxygen of the carboxylato group. The coordination at copper is extended to five by the other oxygen of the carboxylate group of another orotate molecule. Thus, the molecules are associated to form chains, the carboxylato group acting as a bridge between the metal ions, the orotato-group being tridentate. The title compound crystallizes in the monoclinic space group. P21/n1 with a = 9.515(5), b = 6.925(2), c = 11.861(6) Å, β = 95.285(9)°, D calc = 2.17 g cm−3, and z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009596719033
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  • 47
    Digitale Medien
    Digitale Medien
    X-ray crystal structure and spectroscopy of a pseudo-square pyramidal Cu(II) complex, trans-dinitratotetrakis (trans-4-styrylpyridine)copper(II) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 413-420 
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    ISSN: 1572-8854
    Schlagwort(e): pseudo-square pyramidal Cu(II) complex ; trans-4-styrylpyridine ; crystal structure ; IR, electronic, and EPR spectra
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Single crystals of the title Cu(II) complex, [Cu(stpy)4(ONO2)(ONO2)′] [stpy = trans-4-styryl-pyridine] have been prepared and characterized by elemental and thermal analyses, IR, electronic and EPR spectral measurements, and X-ray crystal structure determination. The complex crystallizes in the monoclinic space group P21/c with unit-cell parameters, a = 12.985(2), b = 22.865(8), c = 17.024(10) Å, β = 112.29(3)°, and Z = 4. The structure consists of discrete monomeric units of [Cu(stpy)4(ONO2)(ONO2)′]. The equatorial positions of the Cu(II) polyhedron are occupied by nitrogen atoms of the four stpy ligands and the axial positions by the oxygens of two unidentate nitrate anions. One of these oxygens is at rather longer distance [2.609(3) Å] and may be considered to be semicoordinated. If this semibond is ignored, the coordination geometry lies closer to an idealized square pyramid than to the trigonal bipyramid geometry. IR spectra reveal nitrogen coordination from stpy and asymmetry in the monodentate oxygen binding of the two nitrate ligands. The optical reflectance band at 600 nm suggests pseudo-square-based pyramidal geometry around Cu(II). Well-resolved Cu(II) hyperfine features in the EPR spectra reveal the absence of exchange interactions between adjacent copper centers. Optical and EPR spectra of a methanolic solution of the complex indicate solvent interactions. Thermogravimetric analysis shows the complex to be stable up to 175°C.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009510910121
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  • 48
    Digitale Medien
    Digitale Medien
    Molecular structure of 1-phenyl-1-dimethylamino-4,4-bis(trimethylsilyl)-2-aza-3λ3-phosphabutadiene-1,3 (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 475-480 
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    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; ab initio calculations ; conjugation ; phosphabutadienes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal and molecular structure of 1-phenyl-1-dimethylamino-4,4-bis(trimethylsilyl)-2-aza-3λ3-phosphabutadiene-1,3, Me2N(Ph)C=N—P=C(SiMe3)2 (1), has been determined. Crystal data: triclinic, P1¯, a = 8.975(4), b = 10.001(5), c = 12.440(6) Å, α = 79.04(4), β = 77.98(4), γ = 73.07(4)°, V = 1034.7 Å3, Z = 2, and D c = 1.08 g cm−3. The main geometrical parameters of 1 as well as ab initio (HF/6-31+G**) calculations of the model systems show no clear evidence of high efficiency of the π(C=N)—π (P=C) conjugation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009527413755
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  • 49
    Digitale Medien
    Digitale Medien
    Synthesis and crystal structure of 1-(4-bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 493-496 
    Details
    ISSN: 1572-8854
    Schlagwort(e): contrast agents ; crystal structure ; ortho ester
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract 1-(4-Bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane, C13H15BrO3, has been synthesized from 4-bromophenylacetic acid chloride via the oxetan ester (3-methyl-3-oxetanyl)methyl-2-(4-bromophenyl)acetate. The crystal structure of the title compound has been determined at low temperature (120 K), by X-ray diffraction methods. This compound crystallizes in the monoclinic space group P21/n (No. 14), Z = 4, with lattice parametersa = 6.019(5), b = 20.990(5), c = 9.915(2) Å, and β = 101.29(1)°.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009531514664
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  • 50
    Digitale Medien
    Digitale Medien
    Structure refinement and Raman spectrum of silver azide (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 561-564 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; Raman spectrum ; silver azide ; azide
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Silver nitrate reacts with sodium azide to give white powdery silver azide, which can be crystallized in aqueous ammonia. The compound belongs to orthorhombic space group Ibam with a = 5.600(1), b = 5.980(6), c = 5.998(1) Å, and Z = 4. The layer-type structure is constructed from edge-sharing regular rectangles, each composed of silver atoms at its vertices with an enclosed azide anion in a tilted orientation. The linear and asymmetrical structure of the azide anion in crystalline silver azide has been confirmed by its Raman spectrum.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009544702195
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  • 51
    Digitale Medien
    Digitale Medien
    Structure of adamantan-1-ammonium 1-adamantanecarboxylate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 845-848 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; centrosymmetric ; aminoadamantane derivative ; antiviral ; dispiro compound
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Adamantan-1-ammonium 1-adamantanecarboxylate, C21H33NO2 (I) is a novel dispiro-type compound. Aminoadamantane derivatives, in which the spiro carbon atoms are part of heterocyclic rings, are of potential interest as biological active substances and antiviral agents. Complex (I) crystallizes in the centrosymmetric space group C2/c (No. 15) with eight molecules in the unit cell with a = 25.227(4), b = 6.527(1), c = 22.489(4) Å, and β = 90.75(1)°. The two spiro units are a 1-adamantylammonium cation and a 1-adamantane carbonyloxy anion. The complex units are stabilized by a network of intermolecular carbonyloxy-to-amine hydrogen bonding and van der Waals cohesive forces. Germane bond lengths are: C—N = 1.479(9) and C—O (mean) = 1.25(2) Å.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009564307821
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  • 52
    Digitale Medien
    Digitale Medien
    Structural characterization of a series of cyclohexaphosphates: M0.5((C6H5CH2)2NH2)5P6O18·H2O (M = Co, Cu, Cd) (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 891-899 
    Details
    ISSN: 1572-8854
    Schlagwort(e): cyclohexaphosphates ; organometallic compound ; crystal growth ; X-ray diffraction ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Three new cyclohexaphosphates with general formula M0.5((C6H5CH2)2NH2)5P6O18·H2O (M=Co, Cu, Cd) are reported. They crystallize with monoclinic unit-cells and are isotropic. We have determined their structure from the salt M=Co. This later exhibits the following unit-cell parameters: a = 22.739(5), b = 17.682(3), c = 18.342(3) Å, β = 91.22(1)°, Z = 4,P21/n, V = 7373 Å3, and Dx = 1.373 g cm−3. The atomic arrangement can be described as layers containing P6O18 ring anions and CoO6 octahedra spreading in the (101) planes and intercalated by the dibenzylammonium groups and the water molecules. Synthesis and characterization by X-ray diffraction, IR absorption, and TA are described.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009521911166
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  • 53
    Digitale Medien
    Digitale Medien
    The structural characterization of YbI2(DME)3 (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1107-1110 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; ytterbium ; lanthanide ; coordination complex
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The preparation and structural characterization of [YbI2(DME)2] are reported. The complex crystallizes in the triclinic space group P 1¯: a = 13.0094 (10), b=14.504(3), c = 14.668 (3) Å, α = 115.281(10) β = 106.74(2), γ = 105.97(2)°. The metal center of the complex exhibits a distorted pentagonal bipyramidal coordination geometry which involves a rare example of a monodentate DME ligand.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009557708382
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  • 54
    Digitale Medien
    Digitale Medien
    Crystal structure of phenyl-substituted cyclopentenes (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1127-1132 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; phenyl-substituted cyclopentenes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The crystal structures of two stereoisomers of tetraphenyl- and pentaphenyl-substituted cyclopentenes 1 and 2 have been determined by X-ray analysis. An envelope conformation 1E has been ascertained for the cis isomer 1a, whereas the cis, cis isomer 2a, which crystallizes in two different space groups, P1¯ and P21/n, displays a twisted 2T1 conformation. The phenyl substituents are all tilted with respect to the cyclopentene ring in both structures. Compound 1a crystallizes in the space group P21/a with a = 18.553(3), b = 6.006(2), c = 19.355(5), β = 102.67(4)°, and V = 2104.2(g) Å3 for Z = 4; compound 2a I crystallizes in P21/n with a = 10.064(2), b = 20.756(5), c = 12.245(3) Å, β = 95.21(2)°, and V = 2547(1) Å3 for Z = 4; compound 2aII crystallizes in P1¯ with a = 10.117(3), b = 11.750(2), c = 12.359(2) Å, α = 111.25(2), β = 94.84(2), γ = 108.78(2)°, and V = 1262.3(6) Å3 for Z = 2.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009566010200
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  • 55
    Digitale Medien
    Digitale Medien
    Self-assembly in transition metal complexes: structural characterization of a copper histamine nitrate [Cu(II)(him)2(NO3)2] (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1153-1155 
    Details
    ISSN: 1572-8854
    Schlagwort(e): copper (II) ; histamine ; self-assembly ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract A new monomeric copper (II) complex with histamine (him), [Cu(II)(him)2(No3)2], has been prepared by the reaction of Cu(NO3)2 with histaminium dichloride and its structure was determined by x-ray crystallography. The complex crystallizes in the triclinic system, space group $$P\bar 1$$ with a = 5.7238(4), b = 8.7094(7), c = 9.2481(11) Å, α = 69.693(8), β = 73.242(7), γ = 71.050(7)°, V = 400.84(6) Å3, and Z = 1. The structure consists of discrete [Cu(II)(him)2(NO3)2] molecules in which the metal atom is centrosymmetrically coordinated by two histamine ligands forming an equatorial plane with Cu–N(imidazole ring) being 2.032(2) and Cu–N(NH2 group) being 2.023(2) Å. Two O atoms from nitrate anions coordinate on the elongated axial positions with Cu–O being 2.549(2) Å. In the crystal structure, the molecules are organized by hydrogen bonds forming a two-dimensional network.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009574230460
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  • 56
    Digitale Medien
    Digitale Medien
    14-Hydroxy-14-phenyldibenzo[a,j]xanthene as a lattice host: crystal and molecular structure of its (1:1) complex with diethyl ether (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1179-1186 
    Details
    ISSN: 1572-8854
    Schlagwort(e): xanthenol ; complex ; crystal structure ; H-bonding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title compound 14-hydroxy-14-phenyldibenzo[a,j]xanthene 1 formed a (1:1) complex with diethyl ether. 1,4-Dioxane was also enclathrated, but with a variable stoichiometric ratio. Single crystal X-ray crystallography was used to elucidate the crystal structure of the 1·diethyl ether complex. Crystals are orthorhombic with space group P212121, a = 8.532(3), b = 15.040(4), c = 18.491(5) Å, V = 2373(1) Å3, d c = 1.256 g/cm3, and Z = 4. Host and guest molecules were found to associate via hydrogen bonds, with the guest molecules residing in undulating channels lined by host molecules.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009599432277
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  • 57
    Digitale Medien
    Digitale Medien
    Synthesis, crystal structure and properties of square-planar acetato{[(4-methylimidazol-5-yl)methylene]histamine} copper(II) perchlorate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 409-412 
    Details
    ISSN: 1572-8854
    Schlagwort(e): copper(II) ; Schiff base ; polymidazole ; crystal structure ; properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The square-planar complex [Cu(MIMH)(CH3CO2)](ClO4) (1) (MIMH = [(4-methylimidazol-5-yl)methylene]histamine) was prepared and structurally characterized. Complex 1 crystallizes in the monoclinic space group P21/n with a = 10.5331(10), b = 12.6177(10), c = 12.9773(10) Å, β = 107.710(10)°, V = 1643.0(2) Å3, and Z = 4. Single-crystal X-ray analysis reveals that the copper(II) atom in 1 has a distorted square-planar environment defined by three nitrogen atoms from the Schiff base ligand and one oxygen atom from the acetate group. The Cu—N bond lengths range from 1.950(3) to 2.015(3) Å and the Cu—O(1) bond length is 1.952(2) Å. The electronic spectra of 1 in aqueous solutions indicates that 1 forms adducts of square-pyramidal geometry with H2O. Cyclic voltammetry of 1 in DMF solution shows that there is some degradation of 1 upon reduction.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009558826050
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  • 58
    Digitale Medien
    Digitale Medien
    Crystal and molecular structure of the symmetrical bidentate ligand 3,3-di(1-pyrazolyl)pentane, CH3CH2C(C3H3N2)2CH2CH3 (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 463-467 
    Details
    ISSN: 1572-8854
    Schlagwort(e): pyrazolyl derivative ; substituted pentane ; crystal structure ; bidentate ligand
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The title compound crystallizes in the centrosymmetric space group C2/c with a = 14.4005(23), b = 7.0494(12), c = 11.2462(20) Å, β = 101.572(13)° and Z = 4; the molecule lies on a crystallographic C 2 axis. Hydrogen atoms were both located and refined.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009523312846
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  • 59
    Digitale Medien
    Digitale Medien
    Crystal structure and conformation of frentizole, [1-(6-methoxy-2-benzothiazolyl)-3-phenylurea, an antiviral agent and an immunosuppressive drug (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 1187-1192 
    Details
    ISSN: 1572-8854
    Schlagwort(e): crystal structure ; Frentizole ; immunomodulator ; structure-function relationship
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract Crystals of Frentizole (from ethanol/water) are monoclinic, space group P21/c, with a = 11.187(4), b = 7.392(2), c = 32.727(6) Å, β = 92.77(2)°, Z = 8, D o = 1.47 g/cm3, and D c = 1.472 g/cm3. There are two independent molecules in the crystallographic asymmetric unit with very different conformations. In molecule A the urea group is in the plane of the benzothiazole ring (0.9°) whereas in molecule B the dihedral angle between them is 4.4°. The dihedral angle between the planes of the phenyl group and the benzothiazole ring are ±157° and ±12°, respectively, in the two molecules. The molecules are linked by a pair of N–H···N hydrogen bonds involving the urea nitrogen and two other N–H···N bonds involving the urea nitrogen and the nitrogen of the benzothiazole group.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009551516348
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  • 60
    Digitale Medien
    Digitale Medien
    Crystal structure of quinestrol hemiethanolate (1999)
    Springer
    Journal of chemical crystallography 29 (1999), S. 355-358 
    Details
    ISSN: 1572-8854
    Schlagwort(e): Quinestrol ; sex steroid ; alkyne ; crystal structure ; solvent inclusion ; hydrogen bonding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geologie und Paläontologie , Physik
    Notizen: Abstract The X-ray crystal structure of the synthetic sex steroid quinestrol (3-O-cyclopentyl-17α-ethynylestradiol) as crystallized from ethanolic solution is determined. The asymmetric unit contains two steroid and one ethanol molecules. The conformation of the two steroid molecules differs in the orientation of the cyclopentane ring. The cocrystallized ethanol molecule facilitates formation of cooperative O—H···O hydrogen bonding. The title compound crystallizes in the monoclinic space group P21, with a = 13.950(6), b = 6.5945(8), c = 25.403(8) Å, β = 104.78(4)°, and D calc = 1.136 g cm−1 for Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009590305578
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  • 61
    Digitale Medien
    Digitale Medien
    Integrity and Structural Characteristics of the M6E8 (E=S, Se, Te) Cluster Core: Syntheses and Structures of [Co6S8(PR3)6] n+ (R=Me2Ph, n=1; R=OMe, n=0) (1999)
    Springer
    Journal of cluster science 10 (1999), S. 429-443 
    Details
    ISSN: 1572-8862
    Schlagwort(e): Cluster core M6E8 ; structural characteristics ; crystal structure ; hexacobalt cluster complex ; phosphine ; sulfide bridging
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract Two new members of the hexanuclear series [Co6S8(PR3)6] n+, complexes [Co6S8(PMe2Ph)6](ClO4) (1) and [Co6S8P(OMe)3 6] (2), have been synthesizes and characterized by X-ray diffraction analyses. Their formation process was postulated to go through trinuclear μ3--S bridged moieties. The structural characteristics of the M6E8P6 skeleton of a whole series of [M6E8(PR3)6] n+ (M=Co, Cr, Fe, Mo; E=S, Se, Te) complexes are presented in terms of atomic distances and core volumes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022681127451
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  • 62
    Digitale Medien
    Digitale Medien
    Thermal Decomposition Mechanism and Thermodynamic Properties of [Cd(NTO)4Cd(H2O)6]·4H2O (1999)
    Springer
    Journal of thermal analysis and calorimetry 55 (1999), S. 797-806 
    Details
    ISSN: 1572-8943
    Schlagwort(e): cadmium coordination ; crystal structure ; enthalpy of solution ; lattice energy ; lattice enthalpy ; NTO salt ; preparation ; standard enthalpy of dehydration ; standard enthalpy of formation ; thermal decomposition mechanism
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract [Cd(NTO)4Cd(H2O)6]·4H2O was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one and cadmium carbonate in excess. The single crystal structure was determined by a four-circle X-ray diffractometer. The crystal is monoclinic, space group C2/c with crystal parameters of a=2.1229(3) nm, b=0.6261(8) nm, c=2.1165(3) nm, β=90.602(7)°, V=2.977(6) nm3, Z=4, Dc=2.055 g·cm−3, μ=15.45 cm−1, F(000)=1824, λ(MoKα)=0.071073 nm. The final R is 0.0282. Based on the results of thermal analysis, the thermal decomposition mechanism of [Cd(NTO)4Cd(H2O)6]·4H2O was derived. From measurements of the enthalpy of solution of [Cd(NTO)4Cd(H2O)6]·4H2O in water at 298.15 K, the standard enthalpy of formation, lattice energy, lattice enthalpy and standard enthalpy of dehydration have been determined as -(1747.8±4.8), -2394, -2414 and 313.6 kJ mol−1 respectively.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1010121514909
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  • 63
    Digitale Medien
    Digitale Medien
    Crystal Structures of trans-Tetrahydrotetrols of Benzo[a]pyrene and Chrysene: A Possible Structure-Activity Relationship in Quasi-Planar Bay-Region Polycyclic Aromatic Hydrocarbons (1999)
    Springer
    Structural chemistry 10 (1999), S. 135-148 
    Details
    ISSN: 1572-9001
    Schlagwort(e): Tetrahydrotetrol ; polycyclic aromatic hydrocarbon derivative ; carcinogen ; crystal structure ; structure-activity relationship
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The molecular structures of two racemic trans-tetrahydrotetrols formed by hydrolysis of the (±)anti-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydro derivatives of the strong carcinogen benzo[a]pyrene and the weak carcinogen chrysene have been determined by X-ray crystallographic methods.3 Focusing on the (+)isomers, the stereochemical features of the two tetrols are discussed in detail to determine structural differences, which can be related to the different biological activity of their parent hydrocarbons, since they provide a model for the hydrocarbon moiety in the major PAH-DNA adduct. As a result of this study, a tentative correlation can be stated between biological activity of quasi-planar bay-region PAHs and the presence of structural features, which can decrease the steric hindrance of the aromatic skeleton and the other hydroxy groups on the pseudo-axial O4, which mimics the position of the covalent bond to DNA. The significant structural features seem to be an out-of-plane distortion with a negative torsion angle at the bay region and a half chair conformation of the saturated ring distorted toward the envelope with C8 at the tip as in BPT, in addition to the axial and pseudo-axial conformations of the hydroxy groups at C9 and C10 due to the near bay region. They may be considered generated by trans-opening of the oxirane ring in an anti-diol epoxide biologically active because it is highly strained. The strains, derived from the activation of bay-region PAHs with a negative torsion angle, seem greater in an anti-diol epoxide relative to the syn-isomer. Thus, when the strains are released, the derived trans-tetrol occurs with structural features, which seem to better fit the target. As a consequence, the presence of a methyl group at a bay region should increase the biological activity of a PAH, imposing greater strains to the structure of the anti-diol epoxide.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022037431181
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  • 64
    Digitale Medien
    Digitale Medien
    Survey of Chalcogenide Superconductors (1999)
    Springer
    Journal of thermal analysis and calorimetry 57 (1999), S. 807-821 
    Details
    ISSN: 1572-8943
    Schlagwort(e): bibliography ; critical temperature ; crystal structure ; CuRh2S4 ; CuRh2Se4 ; survey of chalcogenide superconductors
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The thread that runs through all research in the field of superconductivity is new physics through discovery of new materials. The knowledge of superconducting materials has become voluminous and complex. The comprehensive review of the superconducting materials is of particular importance. The main purpose of this report is to present the results of classification for chalcogenide superconductors. Superconducting critical temperature Tc, crystal-structure type and the references proper to these compounds are summarized. Brief survey of the superconductivity in chalcogen elements is also given. Furthermore, as representative sulfide and selenide, superconducting characteristics of CuRh2S4 and CuRh2Se4 will be shown.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1010142225299
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  • 65
    Digitale Medien
    Digitale Medien
    Thermal Decomposition Mechanism, Thermodynamical and Quantum Chemical of Properties [Pb(NTO)2⋅(H2O)] (1999)
    Springer
    Journal of thermal analysis and calorimetry 58 (1999), S. 257-267 
    Details
    ISSN: 1572-8943
    Schlagwort(e): crystal structure ; lattice energy ; lattice enthalpy ; lead salt of NTO ; preparation ; quantum chemical calculation ; thermal decomposition mechanism
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The single crystal of lead salt of 3-nitro-1,2,4-triazol-5-one (NTO), [Pb(NTO)2(H2O)] was prepared and its structure was determined by a four-circle X-ray diffractometer. The crystal is monoclinic, its space group is P21/n with crystal parameters of a=0.7262(1) nm, b=1.2129(2) nm, c=1.2268(3) nm, β=90.38(2)°, V=1.0806(2) nm3, Z=4, Dc=2.97 g cm−3, µ=157.83cm−1, F(000)=888. The final R is 0.027. By using SCF-PM3-MO method we obtained optimized geometry for [Pb(NTO)2⋅H2O] and particularly positions for hydrogen atoms. Through the analyses of MO levels and bond orders it is found that Pb atom bond to ligands mainly with its 6pz and 6py AOs. The thermal decomposition experiments are elucidated when [Pb(NTO)2⋅H2O] is heated, ligand water is dissociated first and NO2 group has priority of leaving. Based on the thermal analysis, the thermal decomposition mechanism of [Pb(NTO)2⋅H2O] has been derived. The lattice enthalpy and its lattice energy were also estimated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1010190811770
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  • 66
    Digitale Medien
    Digitale Medien
    Synthesis of a Novel Nickel(II) Complex with Dithiocarbimate from Sulfonamide (1999)
    Springer
    Structural chemistry 10 (1999), S. 41-45 
    Details
    ISSN: 1572-9001
    Schlagwort(e): Nickel complex ; dithiocarbimate ; sulfonamide ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Potassium N-4-methylphenylsulfonyldithiocarbimate, K2(4-CH3C6H4SO2N=CS2), reacted with nickel(II) chloride hexahydrate and tetrabutylammonium bromide to form the bis(N-4-methylphenylsulfonyldithiocarbimate)nickelate(II) tetrabutylammonium salt (Bu4N)2[Ni(4-CH3C6H4S2C=NSO2)2]. The elemental analyses, IR and UV-Vis data obtained were consistent with the formation of a $${\text{nickel}}{\kern 1pt} - {\kern 1pt} {\text{sulfur}}$$ diamagnetic planar complex. The 1H NMR and the 13C NMR spectra showed the expected signals for the dithiocarbimate moiety and the tetrabutylammonium cation. The single-crystal structure analysis showed that this substance crystallizes in the triclinic $${P\bar 1}$$ space group with a = 10.474(3) Å, b = 10.767(3) Å, c = 13.657(3) Å and α = 81.54(2)°, β = 80.44(2)°, γ = 67.63(2)°, V = 1398.5(8) Å3, and Z = 2. The nickel atom is coordinated to four sulfur atoms.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022018028224
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  • 67
    Digitale Medien
    Digitale Medien
    4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone, a Nicotine-derived Carcinogenic Nitrosaminoketone (NNK): Three-dimensional Structure (1999)
    Springer
    Structural chemistry 10 (1999), S. 439-443 
    Details
    ISSN: 1572-9001
    Schlagwort(e): Nicotine-derived nitrosaminoketone ; nitrosamine ; crystal structure ; molecular dimensions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The three-dimensional structure of the carcinogenic nicotine-derived nitrosaminoketone, 4-(methyl-nitrosamino)-l-(3-pyridyl)-l-butanone, has been determined by X-ray crystallographic techniques. The molecule is essentially planar except for the methylnitrosamine group which is oriented at a dihedral angle of 68.7° to the pyridine ring. Molecules pack by way of —H⋯O interactions that involve the —NNO group.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022431223064
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  • 68
    Digitale Medien
    Digitale Medien
    Structure of the 1 : 1 Complex of Hexakis(2,3,6-tri- O-methyl) α-Cyclodextrin with ( R)-(-)-1,7-Dioxaspiro[5.5]undecane (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 321-330 
    Details
    ISSN: 1573-1111
    Schlagwort(e): crystal structure ; hexakis(2,3,6-triO-methyl)- α-cyclodextrin ; (R)-(-)-1,7-dioxaspiro ; {}[5.5]undecane ; chiral recognition
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The crystal structure of the 1 : 1 inclusion complex of hexakis(2,3,6-tri-O-methyl)- α-cyclodextrin (TM αCD) with 1,7-dioxaspiro[5.5]undecane (spiroacetal) is orthorhombic, space group C2221, with a = 24.002(2), b = 14.812(1), c = 21.792(2) Å V = 7747.3(11) Å3 and Z = 8. The molecular six-fold axis of TM αCD coincides with the a two-fold crystallographic axis and the guest is located at the secondary methoxy group side, disordered over two positions related by that axis. The guest model used during the refinement is that of the (R)-enantiomer alone because trials to either refine a 1 : 1 mixture of (R)- and (S)-enantiomers or the (S)-enantiomer alone failed. The crystallographic evidence of enantioselectivity towards the (R)-enantiomer of spiroacetal was confirmed by independent experiments and may be attributed to numerous non bonding interactions between host and guest involving non conventional H-bonds.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008091718896
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  • 69
    Digitale Medien
    Digitale Medien
    Recent advances in the structure and function of isopenicillin N synthase (1999)
    Springer
    Antonie van Leeuwenhoek 75 (1999), S. 33-39 
    Details
    ISSN: 1572-9699
    Schlagwort(e): active site ; crystal structure ; iron binding motif ; isopenicillin N synthase ; mechanism of action
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Isopenicillin N synthase is a key enzyme in the biosynthesis of penicillin and cephalosporin antibiotics, catalyzing the oxidative ring closure of δ-(L-α-aminoadipoyl)-L-cysteinyl-D-valine to form isopenicillin N. Recent advances in our understanding of the unique chemistry of this enzyme have come through the combined application of spectroscopic, molecular genetic and crystallographic approaches and led to important new insights into the structure and function of this enzyme. Here we review new information on the nature of the endogenous ligands that constitute the ferrous iron active site, sequence evidence for a novel structural motif involved in iron binding in this and related non-heme iron dependent dioxygenases, crystal structure studies on the enzyme and its substrate complex and the impact of these and site-directed mutagenesis studies for unraveling the mechanism of the isopenicillin N synthase reaction.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1001723202234
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  • 70
    Digitale Medien
    Digitale Medien
    QSAR and CoMFA Study of Cocaine Analogs: Crystal and Molecular Structure of (–)-Cocaine Hydrochloride and N-Methyl-3β-(p-Fluorophenyl)Tropane-2β-Carboxylic Acid Methyl Ester (1999)
    Springer
    Structural chemistry 10 (1999), S. 91-103 
    Details
    ISSN: 1572-9001
    Schlagwort(e): x-ray ; crystal structure ; cocaine ; analogs ; QSAR ; CoMFA
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract A QSAR and CoMFA study including 78 cocaine analogs has been completed. These analogs have varied functional groups on the 2β and 3β positions of the tropane ring and include various stereoisomers. The CoMFA program was used to calculate the steric and electrostatic interaction energies as a probe atom or probe charge interacts with the molecules. Shaded contour maps show regions of the cocaine analogs where an increase in bulky substituents is desirable for increased pharmacological activity. The maps also show that small electronegative substituents on the phenyl ring are favored for enhanced activity. The X-ray crystal structures of (–)-cocaine hydrochloride (1) and N-methyl-3β-(p-fluorophenyl)tropane-2β-carboxylic acid methyl ester (2) are reported. These molecules are mostly rigid except for some rotational flexibility in the orientation of the phenyl and benzoyl functional groups. Crystallographic data: (1) C17H21NO4·HCl, orthorhombic space group P212121, a = 7.622(1)Å, b = 10.285(1)Å, c = 21.428(3)Å, Z = 4, final R = 0.035 for 960 observed reflections (I〉3σ(I)). (2) C16H20FNO2, monoclinic space group C2, a = 22.572(7)Å, b = 5.810(1)Å, c = 15.752(4)Å, β = 133.65(2)°, Z = 4, final R = 0.059 for 1511 observed reflections (I〉3σ(I)).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022029129364
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  • 71
    Digitale Medien
    Digitale Medien
    Crystal Structures of Cs+-Crown Ether Complexes Containing Polynuclear Mercury Iodide Anions (1999)
    Springer
    Structural chemistry 10 (1999), S. 177-185 
    Details
    ISSN: 1572-9001
    Schlagwort(e): Cesium complexes ; crown ethers ; mercuric iodide ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Reactions of CsI and HgI2 with benzo-15-crown-5 (B15C5) and 15-crown-5 (15C5) in an ethanol-acetone mixture produced [Cs(B15C5)2]2[Hg2I6] (1) and {[Cs(15C5)]2[Hg2I6]}n (2), respectively. The structures of the two complexes are quite different. Molar ratios of Cs+ : crown ether are 1 : 2 in 1 and 1 : 1 in 2. Complex 1 consists of two Cs(B15C5) 2 + cations and a Hg2I 6 2- anion. Cs+ lies between the two crown-5 ligands, resulting in a sandwich-type cation. Cationic Cs(B15C5) 2 + and anionic Hg2I 6 2- are linked together by electrostatic interactions and the complex 1 is an ion pair compound. Complex 2 consists of infinite [Cs(15C5)]2[Hg2I6] units. Each structural unit contains two Cs(15C5)+ cations and a Hg2I 6 2- anion. Cs+ is coordinated by five oxygen atoms of 15C5, three iodine atoms of Hg2I 6 2- , and an iodine atom of Hg2I 6 2- in an adjacent structural unit. The interactions between the Cs+ of Cs(15C5)+ and an I− in Hg2I 6 2- from adjacent structural units polymerize the complex 2, resulting in a one-dimensional network structure. The anions of Hg2I 6 2- in both complexes are similar. The two mercury atoms are linked through two bridging iodine atoms and each mercury is also coordinated by two terminal iodines. Crystal data for 1: space group P21/c (No. 14), a = 12.253(4), b = 20.945(7), c = 16.110(6) Å, β = 111.0(1)°, V = 3860 Å3, Z = 4, R = 0.082 (R w = 0.089). Crystal data for 2: space group P21/c (No. 14), a = 12.157(4), b = 8.546(4), c = 20.666(6) Å, β = 91.54(3)°, V = 2146 Å3, Z = 4, R = 0.034 (R w = 0.048).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1021832412700
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  • 72
    Digitale Medien
    Digitale Medien
    Studies on (Hg0.7Mo0.3)Sr2(Sr1−xLax)Cu2Oz with a Wide Range of Doping State (1999)
    Springer
    Journal of superconductivity 12 (1999), S. 403-408 
    Details
    ISSN: 1572-9605
    Schlagwort(e): Superconductivity ; crystal structure ; Hg-based cuprate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik , Physik
    Notizen: Abstract The single-phased series of Sr-bearing Hg-1212 superconducting cuprate,(Hg0.7Mo0.3)Sr2(Sr1−x La x )Cu2O z has been prepared. X-ray diffraction showed that, the obtained samples belong to the 1212-structure with tetragonal space group P4/mmm, similar to that of (Hg, Mo)Sr2(Ca, Y)Cu2Oz, and stabilized in a wide compositional range of 0.25≤x≤0.75. Refinements of the structure are carried out in which the oxygen atoms at the (Hg, Mo) layer is shifted from high-symmetry position (0.5, 0.5, 0) to (x, x, 0). Magnetization and electrical resistivity measurements show that the as-prepared samples exhibit evidence for superconductivity and their superconducting properties were improved after O2 annealing with T onset c as high as 92 K.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007765718878
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  • 73
    Digitale Medien
    Digitale Medien
    X-Ray Crystal Structure of Four Inclusion Complexes of the Novel Host Gossindane: An Oxidation Product of Gossypol (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 27-38 
    Details
    ISSN: 1573-1111
    Schlagwort(e): X-ray crystallography ; gossindane ; inclusion complexes ; H-bond ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Gossindane, the oxidation product of gossypol, demonstrates inclusion properties towards four solvents chosen accidentally. The crystal data of these complexes with ethanol (I), ethylacetate (II), dichloromethane (III) and water (IV) are: (I): C26H30O6· 2C2H5OH, monoclinic, P2/c, a = 8.687(2) Å, b = 10.986(3) Å, c = 14.778(3) Å β = 110.94° V = 1317 Å3, Z = 2, R = 0.069, N = 1368; (II): C26H30O6· 0.5C4H8O2, monoclinic, P21/c, a = 8.960(2) Å, b = 21.937(5) Å, c = 14.712(3) Å, β = 111.98(2)°, V = 2681 Å3, Z = 4, R = 0.083, N = 2653; (III): C26H30O6· CH2Cl2, monoclinic, P21/c, a = 8.886(2) Å, b = 21.778(6) Å, c = 14.996(4) Å, β = 111.31(3)°, V = 2704 Å3, Z = 4, R = 0.131, N = 1580; (IV): C26H30O6·2H2O, monoclinic, C2/c, a = 29.422(9) Å, b = 6.720(2) Å, c = 27.525(9) Å, β = 117.43(2)°, V = 4830 Å3, Z = 8. R = 0.096, N = 2240. In the solvates H-bonded host molecules form bilayers with very similar structures and a nearly hydrophobic surface. Guest molecules are placed in channels formed between these bilayers and may be H- bonded to host molecules (ethanol). In the hydrate two water molecules using their H-bonding capacity incorporate gossindane molecules into bilayers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008054114773
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  • 74
    Digitale Medien
    Digitale Medien
    Synthesis of Tetra-N-substituted 1,10-dioxa-4,7,13,16- tetraazacyclooctadecanes and their Application as Lead (II) Selective Electrodes. X-ray Crystal Structure of 4,7,13,16-tetrathenoyl-1,10- dioxa-4,7,13,16-tetraazacyclooctadecane (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 135-148 
    Details
    ISSN: 1573-1111
    Schlagwort(e): ion-selective membrane electrodes ; ionophores ; crystal structure ; tetraazacrown ethers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Tetra-N-substituted 1,10-dioxa-4,7,13,16-tetraazacyclooctadecanes (tetraazacrown ethers) (1-5) have been synthesised. Each compound was incorporated in a PVC membrane that provided the basis for a lead-selective potentiometric electrode. The electrode based on the 4,7,13,16-tetrathenoyl-1,10-dioxa-4,7,13,16- tetraazacyclooctadecane (5) ionophore bearing four thenoyl functional subunits exhibited excellent lead (II) ion selectivity with only Ag+ and Hg2+ significantly interfering. The crystal structure of this host (5) has been determined by single crystal X-ray analysis. Crystal data. C32H36N4O6S4, M 700.9, monoclinic, space group P21/c, a, 10.315(4), b, 13.635(2), c, 14.357(6)Å, β 124.63(2)°, V 1661.6(9)Å3, Dc 1.40 g cm-3, Z 2, μ Cu 29.90 cm-1. Final residuals R, Rw were 0.054, 0.082 for the observed data.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008080423071
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  • 75
    Digitale Medien
    Digitale Medien
    Ditopic Calixcrowns with Inequivalent Crown Loops: Synthesis and Structural Characterisation of an Unsymmetrical Calix[4]arene biscrown-6 (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 251-262 
    Details
    ISSN: 1573-1111
    Schlagwort(e): unsymmetrical ditopic calixcrown ; synthesis ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Consecutive base-catalysed reactions of calix[4]arene with the ditosylates of two different polyetherdiols result in the relatively efficient production of an unsymmetrical calix biscrown-6 which, after reduction of an ethoxycarbonyl substituent to an hydroxymethyl group, has been characterised structurally by a room-temperature, single crystal X-ray study of its chloroform solvate. Crystals of ( 4), C53H62O13... ∼0.57CHCl3, are triclinic, P¯1, a 18.95(3), b 12.394(9), c 11.756(7) Å α 106.93(5), β 101.77(8), γ 94.63(8)°, Z = 2; R was 0.088 for 2231 ’observed' (I 〉 3σ(I)) diffractometer data.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008062510582
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  • 76
    Digitale Medien
    Digitale Medien
    Crown Ether-Dinitrile Interaction: An X-ray Study (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 331-338 
    Details
    ISSN: 1573-1111
    Schlagwort(e): dicyclohexano-18-crown-6 ; succinonitrile ; glutaronitrile ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Formation of the host-guest compounds between isomers of dicyclohexano-18-crown-6 as hosts (DC18C6) and various dinitriles as guests has been observed. The structures of two representative compounds (cis-anti-cis-DC18C6...2(NCCH2CH2CN) ( I) and (cis-syn-cis-DC18C6...(NCCH2CH2CH2CN) ( II) were obtained using X-ray diffractometry. Crystal data: ( I) P=¯1, a = 8.586(3), b = 9.324(3), c = 10.714(4) Å α = 72.47(3)°, β = 73.57(3)°, γ = 72.37(3), R1 = 0.034, GooF 1.08, Z = 1; ( II) Pbca, a = 12.881(5), b = 17.887(8), c = 23.042(13) Å, R1 = 0.049, GooF 1.02, Z = 8. Both structures show weak C–-H...O interactions between α-methylene protons of dinitrile guest molecules and oxygen atoms of the macrocyclic host ring.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008092602058
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  • 77
    Digitale Medien
    Digitale Medien
    Solvent Extraction of Perrhenate with 25,26,27,28-Tetrakis[(ethoxycarbonyl)methoxy]-p- tert-Butylcalix[4]arene and Crystal Structure of the Extracted Complex (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 34 (1999), S. 221-233 
    Details
    ISSN: 1573-1111
    Schlagwort(e): extraction ; perrhenate ; calix[4]arene ; crystal structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The extraction of perrhenate with 25,26,27,28-tetrakis[(ethoxycarbonyl)methoxy]-p-tert-butylcali x[4]arene ( L) into 1,2-dichloroethane was investigated. The presence of Na+ in the aqueous phase is necessary for the extraction. The extraction equilibrium has been established and the thermodynamic quantities ΔH°, TΔS° and log Kex are -61.3 kJ/mol, -41.4 kJ/mol and 3.69, respectively. The effect of diverse ions on the extraction of ReO4- was studied. The corresponding extracted complex [Na L]ReO4.H2O was prepared and characterized by EA, IR and X-ray structure analysis. The complex crystallizes in the tetragonal space group P4ncc with a = b = 14.735(3), c = 29.094(3) Å, V = 6316(2) Å3, Z = 4.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008041507177
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  • 78
    Digitale Medien
    Digitale Medien
    Structure of an Inclusion Compound of 28,28,35,35-Tetramethyl-11-oxo-1,4,18,21-tetraoxa[4,1,4,1,1]paracycloph ane with para-Xylene (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 34 (1999), S. 267-276 
    Details
    ISSN: 1573-1111
    Schlagwort(e): tetraoxaparacyclophane complex ; preparation ; crystal structure ; clathrate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The structure of the 2:3 complex between cyclophane 1 and para-xylene has been determined by a single crystal X-ray diffraction study at 143 K. One para-xylene molecule is enclosed within the cavity formed by two molecules of the host cyclophane; this ensemble displays crystallographic inversion symmetry. The other independent para-xylene molecule is located on a general position in the intermolecular cavities of the crystal lattice. The complex crystallizes in the triclinic space group P(-1) with a = 10β = 89.51(3), γ = 87.26(2)°, and Z = 1. Refinement based on 7539 unique reflections led to a final R(F) value of 0.0609.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008085829837
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  • 79
    Digitale Medien
    Digitale Medien
    Structural Study of C-undecylcalix[4]resorcinarene Solvate with Dioxane (1999)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 35 (1999), S. 131-138 
    Details
    ISSN: 1573-1111
    Schlagwort(e): C-undecylcalix[4]resorcinarene ; crystal structure ; dioxane solvation ; exo molecular complex
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The crystal structure of the molecular complex of C-undecylcalix[4]resorcinarene with dioxane has been determined by X-ray analysis. The asymmetric unit contains one host and four guest molecules. The calix[4]resorcinarene moiety adopts a bowl conformation with C4v symmetry. Four undecyl chains are axially oriented. Calix molecules are packed in a bowl-to-bowl fashion with alternating hydrophilic and hydrophobic layers. One of the ‘hydrophilic’ dioxane molecules is located at the rim of the calix moiety and is hydrogen bonded to the other one. There is no interaction to attract, or direct the dioxane molecule into the interior of the cavity. There is an exo complex formed. The dioxane molecules – located in the hydrophobic part – are highly disordered.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008115002434
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  • 80
    Digitale Medien
    Digitale Medien
    The structure of the testis and movement of sperms in chortophaga viridifasciata as demonstrated by intravitam techniqueA dissertation presented to the Faculty of Kansas University in partial fulfillment of the requirements for the Degree of Doctor of Philosophy.I wish to express sincere gratitude to my major professor, Dr. W. J. Baumgartner, for his continual assistance and efficient direction during the development of this work. His helpful encouragement and invaluable suggestions, as well as the kindly interest manifested by other members of the faculty, will keep me ever a debtor to the University of Kansas. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 321-345 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: By means of the ‘intravitam technic’ developed by Baumgartner and Payne (1931), the mature or maturing sperm of Chortophaga viridifasciata have been traced from the follicle of the testes in the male to the locus of fertilization in the female. The sperm aggregated into bundles, and held tight by a hyaline cytoplasmic cap, spiral up the follicle, turn and spiral back to the vas deferens by means of a periodic lashing and writhing of the sperm tails.The genital tract is described briefly. In the vasa deferentia and storage tubules, the sperm bundles are usually in a quiescent state, having been inactivated most probably by secretions from the tubules.Peristalsis and currents in the fluid contents of the tubules move the inactivated sperm from the vesicles of the male to the seminal receptacle of the female, where the cytoplasmic caps gradually disintegrate. This permits individual sperm to pass down the seminal duct and fertilize the ovum just before oviposition.Single photomicrographs and a series of photomicrographs show the sperm in various parts of the genital system and making actual progress up a follicle. A stained preparation was used for only one of the photos. The other nineteen are from living unstained tissue. The intravitam observations are, most probably, more ‘vital’ than any heretofore recorded.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540205
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  • 81
    Digitale Medien
    Digitale Medien
    Masthead (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540201
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  • 82
    Digitale Medien
    Digitale Medien
    A study of the Golgi elementsSubmitted from the Department of Zoology in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of the University of Missouri, 1931. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 259-301 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: This investigation was undertaken to determine some of the variables involved in the demonstration of the Golgi elements. Gland cells of vertebrates were studied vitally, after impregnation by osmic acid methods, and after autolysis.The duration of the staining period and the concentration of the stain condition the results obtained by vital staining with neutral red. The success of impregnation of Golgi elements with osmic acid varies with,(1) the type of tissue, (2) the time of initial fixation in relation to the time of the death of the animal, (3) the position of the cell in the piece of tissue, and, (4) the temperature of incubation with osmic acid. Stages in the impregnation of Golgi elements can be followed by examining preparations of the same tissue at frequent intervals during the incubation period. An increase in the amount of material which reduces osmic acid and which may form Golgi elements occurs in the cells during autolysis.The results are interpreted as indicating that Golgi elements are visible products of chemical reactions that occur in cells. They represent localized regions containing particular classes of chemical compounds which may be present, as such, in living cells or result from transformations in the cells during incubation. It is suggested that for the cells under consideration these substances may be unsaturated fatty acids.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540203
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  • 83
    Digitale Medien
    Digitale Medien
    The architecture of the pectoral appendage of the dogfish (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 399-413 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The m. trapezius, with both brachial and branchial functions, is in seeming series with the mm. interarcuales laterales. The intrinsic muscles of the fin occur as a dorsal extensor sheet and three (or four) ventral flexor components. The spinal nerves, uncomplicated by extensive anastomoses, which supply the fin, clearly show that in the dogfish the fin muscles are derived not from dorsal and ventral elements, but from anterior and posterior, or protractor and retractor elements. The nerves prove that from the original protractor musculature only the anterior portion of the present flexor group is derived, while the original retractor musculature has become all of the extensor and the posterior part of the flexor series. Faradic stimulation of the live animal is satisfactory, although there is much variation in the sensitivity, particularly of different muscles.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540209
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  • 84
    Digitale Medien
    Digitale Medien
    Observations on spermiogenesis in sciara coprophila (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 477-491 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The mitochondria in the male germ cells of Sciara exhibit peculiarities as regards both morphological characteristics and distribution. In form. they show superficial similarity with those of some of the scorpions, while their distribution may be peculiar to the genus and depend on unusual meiotic divisions.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540305
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  • 85
    Digitale Medien
    Digitale Medien
    The anatomy and blood supply of the urogenital system of lepidosteus platystomus rafinesque (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 459-475 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: A description of the urogenital system in both sexes of Lepidosteus platystomus Rafinesque, and new observations on the blood supply to this system as well as to the rest of the viscera is given.The testes resemble the true piscine type. The sperm are carried by numerous vasa efferentia to the kidney tubules, through the mesonephros to the wolffian duct, and to the exterior as in the elasmobranchs and amphibians. The most anterior of the vasa efferentia are non-functional. The ovaries are simple sac-like structures continuous with their ducts. The oviducts transverse the ventro-lateral surface of the mesonephros, and enter into the dilated portions of the wolffian ducts, where they join, directly anterior to the urogenital aperture. There are no ducts in the male homologous with the oviducts of the female. The kidneys fused posteriorly, appear to extend the entire length of the body cavity, but the anterior third is non-urinary.By injection methods, the celiaco-mesenteric artery is shown to be crowded to the posterior end of the body cavity by the complicated swim-bladder, and runs anteriorly to supply the entire viscera. Its anterior portion is incorporated in the liver.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540304
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  • 86
    Digitale Medien
    Digitale Medien
    Masthead (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550101
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  • 87
    Digitale Medien
    Digitale Medien
    Musculature of the lacewing (chrysopa plorabunda) neuroptera (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 29-51 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: This article is an account of the complete musculature of an adult Neuropteran insect, Chrysopa plorabunda. Previous anatomical discussions on this order of insects include only a few of the muscles of the head and thoracic regions, while those of the abdomen are entirely lacking. The muscles here described include those of the head, thorax, and abdomen. The origin, insertion, and function of each muscle is given. The boundaries of several of the sclerites, especially those of the labium, are located by the observations on the musculature of these parts. The meso- and metathoracic wings are of the same size and for that reason the muscles of these regions are very much alike. The prothorax is greatly elonated, causing the muscles of that region to differ to a greater or less degree from the ‘general rule’ in insects. The abdominal muscles may be arranged in the several groups generally found in insects. In several cases, however, both the origin and insertion of the muscle have been shifted to accompany changes which have taken place in the abdominal segmentation. All of the muscles are shown in the four plates containing nineteen figures which accompany the text.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550104
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  • 88
    Digitale Medien
    Digitale Medien
    Some ultraviolet photomicrographs made with different wave lengths (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 131-135 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Photomicrographs have been made of grasshopper spermatocytes using ultraviolet light of several wave lengths. For studying chromosomes this wave length should be between ca 2800 A and ca 2500 A. With higher frequencies the entire cell becomes strongly absorbing and relatively little detail is to be seen. All cell structures, including the chromosomes, are as transparent to λ = 3500 A and to longer ultraviolet waves as they are to visible light. The present experiments do not indicate the exact point between λ = 3500 A and λ = 2800 A at which the selective chromatin absorption commences.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550108
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  • 89
    Digitale Medien
    Digitale Medien
    An embryological study of a special strain of deformed x-rayed mice, with special reference to the etiology and morphogenesis of the abnormalitiesContribution from the Zoölogical Laboratory of the University of Michigan. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 151-183 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: This investigation consists of an extensive histological study of a special strain of abnormal x-rayed mice, in an attempt to determine the embryonic origin and development of certain congenital abnormalities that are hereditary.The study shows that development of the x-rayed strain is normal up to the thirteenth day after insemination, after which pathological structures appear in the form of blebs, hematomas, and thrombi. As a result of the formation of the blebs and hematomas a general condition is set up within the embryo which resembles that of thrombosis. The thrombi when formed exert a mechanical effect by crowding out the normal tissue. A chemical effect is also produced by the blood cells and fluid extravasated from the thrombus which penetrate into the forming tissues resulting in their perverted development. Thus the thrombi are the immediate factors causing the various regions of the body to be deformed.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550110
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  • 90
    Digitale Medien
    Digitale Medien
    Viviparity superimposed upon ovo-viviparity in the goodeidae, a family of cyprinodont teleost fishes of the Mexican Plateau (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 207-251 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The Goodeidae are a family of cyprinodonts containing about nine genera and twenty-six species. They are confined exclusively to the Mexican Plateau and to streams in the immediate vicinity. All are viviparous. Fertilization is internal. The eggs are extremely small and contain very little yolk. The embryos are retained in the ovarian follicles until the yolk is practically absorbed, in the meantime developing unique absorptive organs in the form of extensive ribbon-shaped proctodaeal processes. The embryos are evacuated into the intra-ovarian cavity where they are retained for several weeks, during which time the proctodaeal processes become extended. The ovary becomes a nutritive organ and produces secretions which are discharged into the intra-ovarian cavity and absorbed by the embryo through their unique processes. The processes differ in form, number, and histological structure, but are specific in their peculiarities for each species. These specific differences, together with marked differences in the ovary, will furnish a basis for a re-classification of the genera and species of the family. A comparison in made between this family and the other ovo-viviparous and viviparous cyprinodonts, on the basis of which it is concluded that the Goodeidae have arisen separately from an ovo-viviparous ancestor, which in turn was derived from an ovo-viviparous type. A comparison is also made between the peculiarities of reproduction in this family and those of other viviparous teleosts.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550202
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  • 91
    Digitale Medien
    Digitale Medien
    An experimental study of hemopoiesis in necturus: Effects of lead poisoning on normal and splenectomized animals (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 349-385 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Lead poisoning causes a selective destruction of mature erythrocytes, thereby depleting the spleen and stimulating differentiation and proliferation of erythrocytes in the blood. In conjunction with splenectomy, this intravascular erythropoiesis is markedly accelerated.During the progressive anemia and subsequent regeneration of erythrocytes in simple lead poisoning the major hemopoietic loci, spleen, mesonephros, liver, and epicardium were observed. The spleen is most rapidly affected. The red cell progenitor first present in the circulation is the hemoblast, but later numerous lymphocytes enter the blood stream and are transformed into erythrocytes.Following simple splenectomy the blood shows relatively little change. A mild regenerative activity of both erythrocytes and thrombocytes ensues. In lead poisoning after splenectomy the blood picture resembles that of simple lead poisoning. The anemia is produced more rapidly and the regeneration of erythrocytes is delayed.This study emphasizes the importance of the blood stream of Necturus as a site of red cell differentiation and proliferation, and shows that the lymphocyte may be a possible progenitor of erythrocytes and thrombocytes. Under normal conditions the hemoblast suffices as a source for red cells, but under abnormal or experimental conditions, where the demand for new cells is excessive and prolonged, the lymphocyte plays a major role.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550206
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  • 92
    Digitale Medien
    Digitale Medien
    Morphogenesis of the brain (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 233-258 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The fundamental structure of the brain stem is uniform throughout the vertebrate series, not essentially because it expresses an architypical pattern, but because of the constancy of peripheral connections and their internal relationships, both of which are parts of an apparatus of adjustment to environment which is common to vertebrates. Other parts of the brain are more variable because, with complication of the behavior pattern in higher forms, more elaborate and diversified mechanisms of correlation and integration are requisite.The brain stem between the olfactory bulb and other primary sensory centers is plastic tissue not dominated by any single sensory-motor system; it is the meeting place of descending and ascending sensory paths. Here the chief apparatus of correlation and integration is elaborated. From it emerge the complex thalamic and cortical adjustors. The pallium is not a primary constituent of the vertebrate brain. The pallial type of organization gradually emerged from the more ancient subpallial type and comes to mature expression in the cerebral cortex. Several instructive stages in the progressive differentiation of cortical structure and connections are seen in the amphibian forebrain, but the process is not consummated. Amphibia have no cerebral cortex, though cortical primordia are evident here and in various fishes. Static concepts of architypes and the dialectic of ‘form-analytic’ argumentation are replaced by a more dynamic treatment of morphogenesis.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540202
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  • 93
    Digitale Medien
    Digitale Medien
    The inheritance of cataract in man, pedigree and interpretation (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 347-363 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: From a mating of first-cousins, of whom the female had cataract, there issued in four generations a progeny of 138 individuals, 33 of whom had cataract (23.8 per cent). Discounting the last generation, about which little is known, also discounting other unknown members, there were 29 known unaffected, 30 known affected, i.e., 50.8 per cent had cataract. The pedigree by generations shows that cataract is inherited as an autosomal (Mendelian) dominant. However, the mode of inheritance is atypical in that the defective gene for cataract may be borne, and is so borne because transmitted, without producing in the bearer its characteristic defect. In the second generation there were four of a family of nine with cataract; of the five without cataract two produced cataractous offspring and three did not marry. The literature is replete with pedigrees in which cataract is inherited as a typical autosomal dominant; there are a few pedigrees (four are reproduced) in which the mode of inheritance, while distinctly that of an autosomal dominant, resembles the present pedigree in being atypical. It is concluded that cataract is inherited as an autosomal dominant, but that in some cases it is produced only under certain conditions. These conditions are as yet not definitely known. Clinical writers seem to favor the view that nutritional and endocrine disturbances predispose to the realization of the defect.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540206
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  • 94
    Digitale Medien
    Digitale Medien
    An anatomical study of the furless condition in rabbits (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 365-388 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: A histological study of Hammond's simple recessive ‘furless’ rabbits was made from many series of sections taken from the skin of both the normal and furless rabbits of several pertinent ages.It was found that the external absence of under-hair or fur exists because of a failure of the hairs of these follicles to erupt. This failure is due to a premature keratinization which first affects the sebaceous glands and then the inner epithelial sheath. The resulting abnormal channel allows an erratic escape, especially of the regenerating hair above the incomplete inner sheath into the surrounding connective tissue, where the escaped part of the hair atrophies. The final condition shows an inflammatory reaction in the areolar tissue here. There is no check on the growth from the bulb of the root. Other elements of the skin verify this excessive keratinization.The cause of the abnormal metabolic changes conceivably lies in an inadequate tissue supply of oxygen or nutrition. The regulator may be the sympathetic system directly or indirectly (by hormone action), or it may be an inhibitor resident in the integument itself.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540207
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  • 95
    Digitale Medien
    Digitale Medien
    Histology of the fresh-water mussel heart with reference to its physiological reactionsThe writer wishes to express his obligation to the United States Bureau of Fisheries for the material used in these studies, and his indebtedness to Dr. M. M. Ellis for the helpful advice given during the course of these investigations. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 415-427 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The anatomical isolation of the auricles from the ventricle in hearts of fresh-water mussels representing nine North American species has been confirmed. The muscle fibers in these hearts without exceptions were found to be of the smooth, unstriated type. Bundles of these fibers loosely interwoven, form the thin, delicate, heart wall, which contains many sinus-like spaces. The outside portion of the heart wall exposed to the pericardial fluid is covered with a definite epicardium composed of a single, dense layer of epithelial and scattering mucous cells. The inside of the heart cavity has no endocardium, the muscle fibers being in direct contact with the blood. No special conduction tissue, nerves or ganglia were found in the heart wall. Correlations of these anatomical and histological findings with the physiological reactions of the living heart in situ are made, and the mechanical and chemical control of the heart discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540210
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  • 96
    Digitale Medien
    Digitale Medien
    The effects of X-rays on anterior regeneration in tubifex tubifexThis study was made during 1931-32 at the zoölogical laboratories of the University of Missouri and the University of Pennsylvania, while on appointment as a National Research Council Fellow. It is in continuation of previous work at the University of Missouri supported in part by the Committee on Radiation of the National Research Council. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 303-320 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Observations of earlier workers concerning the limited region from which anterior regeneration will occur in Tubifex and the reduced number of segments formed were confirmed in control worms used in these experiments. Only three anterior segments are replaced when as many as twelve are removed. Regeneration is completed within 18 days.Removal of anterior segments from worms that have received 9000 (r) units exposure to x-rays is not followed by regeneration. The wound heals rapidly and worms have been kept in laboratory 70 days without further change. Longitudinal sect ons of injured ends show that the epidermis and muscle layers extend across the wound surface to completely close the body cavity. The intestine retracts slightly and heals to form a blind tube. No mitotic figures appear in cells of this region and there is no evidence of regeneration.In control worms material for formation of the cerebral ganglia and new epidermis arises by proliferation of epidermal cells. The new pharynx arises from the region of the old intestine adjacent to the wound surface. The muscle layers of the body wall and pharynx in new segments are apparently formed by migration of cells from the old muscle elements about the margin of the wound area. No neoblasts were observed in anterior migration or in the process of formation upon adjacent septa in any of the worms.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540204
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  • 97
    Digitale Medien
    Digitale Medien
    Masthead (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540301
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  • 98
    Digitale Medien
    Digitale Medien
    The rudimentary copulatory organ of the domestic fowl (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 429-449 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The rudimentary copulatory organ of chickens was first observed as a phallic knob in 6-day embryos. This phallic knob enlarged similarly in both male and female embryos up to the twelfth day: from the twelfth to the seventeenth day it was distinguished by a large process in the males and a diminishing process in the females. Further differentiation took place from the eighteenth to the twenty-first days: some females lacked the porcess, others retained a smaller process than that of the male. As growth advance, fewer females retained the process until at 12 weeks of age it had entirely disappeared. The process was found in all males and showed no retrogression, whereas the few capons examined lacked it. A ridge-shaped ‘pseudo’ process developed at about 1 week in some females and was present up to 3 weeks of age. Histologically and embryologically, the process was seen to possess some characteristics of a penis. The cloacal method of sex determination might be used with an average maximum accuracy of about 90 per cent in living day-old chicks.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540302
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  • 99
    Digitale Medien
    Digitale Medien
    Sex cycles and other cyclic phenomena in a chimpanzee during adolescence, maturity, and pregnancy (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 54 (1933), S. 521-547 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The sex cycles of a chimpanzee were studied for 18 months, during which the animal matured, menstruated four times, conceived, and delivered.Pronounced swelling of the ano-genital region appeared periodically prior to the first menstruation. During menstrual cycles the swelling endured during most of the period between flows. Genital swelling was always accompanied by estrus; copulation and insemination never occurred during its absence.The animal was alert and active when in estrus, demonstrated non-sexual affection for the male just prior to the flow, and appeared to be physically distressed during the first days of each flow.There were periodic weight changes coordinated with the animal's menstrual cycles.During pregnancy menstruation ceased, but genital swelling, with accompanying sexual receptivity, continued in irregular cycles.Cyclic changes in the desquamation of the vaginal epithelium occurred during menstrual cycles, were absent during pregnancy.The gestation period was approximately 246 days. At death from puerperal sepsis, 15 days after delivery, the ovaries were in a restin stage, one of them bearing a degenerating corpus luteum.The evidence given indicates that sex-skin swelling and estrus are similarly controlled, but may occur independently of menstruation, cornification of the vaginal epithelium, or ovulation.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050540307
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  • 100
    Digitale Medien
    Digitale Medien
    The genitalia of the Indian mollusk Indoplanorbis exustusContribution from the Museum of Natural History, University of Illinois, No. 71. (1933)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 55 (1933), S. 1-13 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The molluscan genus Indoplanorbis is shown to differ markedly from all other members of the family Planorbidae in the generative complex, the vas deferens being encased in a long, flexible tube in which it is freely movable. The preputium of the male complex is shown to be completely evertible from the male opening and to act as a male copulatory organ. The presence of a single, heavy penial retractor innervated by an equally strong nerve is indicated. Comparisons are made with the genitalia of the European Coretus and the American Helisoma showing fundamental differences in the generative apparatus of the three groups. Indoplanorbis is most closely related to Coretus, the vas deferens of that group being also encased in a tube. Helisoma differs from both of these genera, the vas deferens not being encased in a tube and is of the same diameter throughout its length.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1050550102
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