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1

Digitale Medien

Crystal structure of [Mn2(III)(salpa)2Cl2(H2O)2] (H2salpa = 1-(salicylaldeneamino)-3-hydroxypropane) (1999)

Zhang, Cun-Gen ; Sun, Jie ; Kong, Xiang-Fu ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 203-206

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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

Molecular structure of ThBr4(DME)2 (DME = 1,2-dimethoxyethane) (1999)

Rabinovich, Daniel ; Scott, Brian L. ; Nielsen, Jon B. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 243-246

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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

Synthesis and crystal structure of the copper(II) complex with novel Schiff base ligand: Cu(C8H7O2N)2(OH2) (1999)

Kong, Deyuan ; Xie, Yuli ; Xie, Yuyuan ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 295-298

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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

Synthesis and crystal structures of quadruply carboxylate-bridged dimeric lanthanide(III) complexes of betaine (1999)

Yang, Guang ; Chen, Hui-An ; Zhou, Zhong-Yuan ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 309-316

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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

Copper, a chemical Janus: two copper(II) complexes with different ligand in one single crystal (1999)

Yan, Shiping ; Li, Chunhui ; Cheng, Peng ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1085-1088

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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

Molecular gears: Structures of (9,10-triptyceno) crown ethers (1999)

Bryan, Jeffrey C. ; Sachleben, Richard A. ; Gakh, Andrei A. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 513-521

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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

The structure of bis(trimethylammonium) undecachlorotriantimonate(III) [(CH3)3NH]2Sb3Cl11 containing a novel antimony(III) anion (1999)

Bujak, Maciej ; Zaleski, Jacek

Springer

Journal of chemical crystallography 29 (1999), S. 555-560

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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

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)

Hueso-Ureña, Francisco ; Jiménez-Pulido, Sonia B. ; Moreno-Carretero, Miguel N. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 571-574

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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

Synthesis and characterization of the dodecanuclear heterobimetallic Mo—Cu—S cage cluster: (Ph4P)2[{Mo2Cu2O2S2(S2)2}3(μ6-S)] (1999)

Lin, Ping ; Wu, Xintao ; Chen, Ling ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 581-586

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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

Crystal and molecular structure of five coordinate copper(II) complex with 2,6-bis[1-(methoxycarbonylmethyl–hydrazono)ethyl] pyridine (1999)

Andjelković, K. ; Tellgren, R. ; Niketić, S.R. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 575-580

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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

Synthesis and crystal structure of the heterometallic square-chain polythiometalate: {[W4Ag5S16]2 · [La(DEF)2(DMF)6][La(DEF)4(DMF)4]}n (1999)

Ling, Chen ; Xintao, Wu ; Ping, Lin

Springer

Journal of chemical crystallography 29 (1999), S. 629-633

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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

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)

Churchill, Melvyn Rowen ; Churchill, David George ; Ahmed, Gulzar ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 707-711

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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

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)

Churchill, Melvyn Rowen ; Churchill, David George ; Ahmed, Gulzar ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 713-717

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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

Synthesis and crystal structure of 1,1′-di(ethylpropionato)-2,2′-biimidazole, a macromolecular precursor (1999)

Barnett, W. Mark ; Baughman, Russell G. ; Collier, Harvest L. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 765-768

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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

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)

Casas, José S. ; Castellano, Eduardo E. ; Ellena, Javier ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 831-836

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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

Generation and intermolecular trapping of a cage-annulated cycloalkylidenecarbene (1999)

Bott, Simon G. ; Marchand, Alan P. ; Dong, Eric Zhiming

Springer

Journal of chemical crystallography 29 (1999), S. 329-333

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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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Crystal structure of the addition compound of N,N′-bi(2-pyridylmethyl)-oxamide and complex of manganese with 1,10-phenanthroline (1999)

Liu, Bin ; Wang, Hong-Mei ; Yan, Shi-Ping ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 623-627

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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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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)

Churchill, Melvyn Rowen ; Churchill, David George ; Huynh, My Hang Vo ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 659-665

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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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Synthesis and crystal structure of 4,5-(cis-cyclohexylenedithio)-1,3-dithiole-2-one (1999)

Bai, Jun-Feng ; Zuo, Jing-Lin ; Shi, Fa-Nian ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 719-723

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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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The crystal and molecular structure of 2-S-methylthiouracil (1999)

Casas, J.S. ; Castellano, E.E. ; García-Tasende, M.S. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 725-727

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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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Crystal structure and emission study of [(PPh3)2Cu(dmp)-O-(dmp)Cu(PPh3)2]2+ (dmp = 2,9-dimethyl-1,10-phenanthroline) (1999)

Lu, Juan ; Whittlesey, Bruce ; Casadonte, Dominick J.

Springer

Journal of chemical crystallography 29 (1999), S. 797-802

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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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Structural analysis of tris(tetra-n-butylammonium) hexakisisothiocyanatoyttrate(III) (1999)

Kautz, Jason A. ; Mullica, Donald F. ; Farmer, J. Matt

Springer

Journal of chemical crystallography 29 (1999), S. 729-733

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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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Synthesis and structure of bis(dibenzoylmethane)copper(II) (1999)

Ma, Bao-Qing ; Gao, Song ; Wang, Zhe-Ming ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 793-796

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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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Crystal structure of [WBr2(CO)(PPh2Cy)2(η2-MeC2Me)]·CH2Cl2 (Cy = cyclohexyl) (1999)

Baker, Paul K. ; Drew, Michael G.B. ; Meehan, Margaret M.

Springer

Journal of chemical crystallography 29 (1999), S. 809-812

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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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1-(Ethoxymethyl)-6-(phenylselenyl)-5-ethyl uracil: a nucleoside analog (1999)

Mazumder, G. ; De, M. ; Mukhopadhyay, A. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 837-839

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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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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)

Freire, Eleonora ; Baggio, Sergio ; Baggio, Ricardo ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 825-830

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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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Synthesis and crystal structure of [WI(CO)(cis-dppen) η2-MeC2Me)2]I·CH2Cl2 {cis-dppen = bis(diphenylphosphino)ethene} (1999)

Baker, Paul K. ; Drew, Michael G.B. ; Latif, Latifah A.

Springer

Journal of chemical crystallography 29 (1999), S. 907-911

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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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4-(1,4-Dimethoxy-2-naphthyl)-4- hydroxycyclohexanone and its ethylene ketal (1999)

Wiedenfeld, David ; Xiao, Wu ; Gravelle, Philip W.

Springer

Journal of chemical crystallography 29 (1999), S. 955-959

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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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Crystal structure and physical characterization of neotame methanol solvate (1999)

Dong, Zedong ; Young, Victor G. ; Padden, Brian E. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 967-975

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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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A study of two geometric isomers of 1,1′-bi-3-cyanocyclohex-2-enylidene (1999)

Wang, Yonghui ; Doering, W.v.E. ; Staples, Richard J.

Springer

Journal of chemical crystallography 29 (1999), S. 977-982

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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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X-ray crystal structure of tetraaquabis (xanthosinato)nickel(II) hexahydrate (1999)

Barrios, Francisca ; Salas, Juan M. ; Sánchez, M. Purificación ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1009-1013

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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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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)

Islam, Manwarul ; Johns, Caroline A. ; Kabir, Shariff E. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1001-1007

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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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Crystal structure of 1,3-di-2-[(4-methoxyphenyl)-1-diazenyl]imidazolidine (1999)

Biradha, Kumar ; Jenkins, Hilary ; Peori, M. Brad ; [weitere]

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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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)

Moers, Frans G. ; Nayak, Sandip K. ; de Gelder, René ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1053-1056

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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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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)

Churchill, Melvyn Rowen ; Churchill, David George ; Matasi, Julius J. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1061-1066

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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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Crystal structure of [Co(bipy)(maleato) (H2O)3]·H2O (bipy = 2,2′-bipyridine) (1999)

Zhang, Cun-Gen ; Leng, Yong-Jun ; Ma, Zi-Feng ; [weitere]

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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Crystal and molecular structure determination, TGA, DTA, and infrared and Raman spectra of rubidium nitroprusside monohydrate, Rb2[Fe(CN)5NO]·H2O (1999)

Soria, D.B. ; Piro, O.E. ; Castellano, E.E. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 75-80

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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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Crystal structure of methyl trans-3-[(2-(methoxycarbonyl)phenyl)sulfinyl]acrylate: a product resulting from trapping of a sulfenic acid by methyl propiolate (1999)

Mitra, Kaushik ; Barnes, Charles L. ; Gates, Kent S.

Springer

Journal of chemical crystallography 29 (1999), S. 1133-1136

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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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9[1-(2-Hydroxy ethoxy)-3-hydroxy propyl] guanine: a nucleoside analog (1999)

Mazumder, G. ; De, M. ; Mukhopadhyay, A. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1137-1139

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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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Structure, thermal behavior, and IR investigation of a new organic sulfate (1999)

Guerfel, Taha ; Bdiri, Mohamed ; Jouini, Amor

Springer

Journal of chemical crystallography 29 (1999), S. 1205-1210

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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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Structure of de-oxy corticosterone-21-hemisuccinate (1999)

Dey, Raja ; Roychowdhury, Sandhya ; Roychowdhury, P.

Springer

Journal of chemical crystallography 29 (1999), S. 1265-1269

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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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Synthesis and crystal structure of 1-phenyl-3-methylthio-4-imino-5-allyl-pyrazolo[3,4-d]pyrimidine (1999)

Chen, Weiqiang ; Weng, Linhong ; Jin, Guiyu

Springer

Journal of chemical crystallography 29 (1999), S. 1291-1293

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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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Crystal structure of [Mn(II)(phen)(ClCH2COO)2]n (phen = 1,10−phenanthroline) (1999)

Zhang, Cun-Gen ; Sun, Jie ; Kong, Xiang-Fu ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 199-201

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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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Synthesis of a new dibenzo-14-crown-4 lariat ether and structure of its sodium perrhenate complex (1999)

Bryan, Jeffrey C. ; Sachleben, Richard A.

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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Structure of de-oxy corticosterone (4-pregnen-21-ol-3,20-dione) (1999)

Dey, Raja ; Roychowdhury, Sandhya ; Roychowdhury, P. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1271-1275

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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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Polymeric copper(II)-orotato complexes, [(C5H2N2O4)Cu(H2O)2]n (1999)

Ha, Tam T.B. ; Larsonneur-Galibert, Anne Marie ; Castan, Paule ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 565-569

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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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X-ray crystal structure and spectroscopy of a pseudo-square pyramidal Cu(II) complex, trans-dinitratotetrakis (trans-4-styrylpyridine)copper(II) (1999)

Karunakaran, Chandran ; Thomas, K.R. Justin ; Shunmugasundaram, Arunachalam ; [weitere]

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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Molecular structure of 1-phenyl-1-dimethylamino-4,4-bis(trimethylsilyl)-2-aza-3λ3-phosphabutadiene-1,3 (1999)

Chernega, Alexander N. ; Rusanov, Eduard B. ; Povolotskii, Mark I.

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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Synthesis and crystal structure of 1-(4-bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane (1999)

Løiten, Marianne Sveaas ; Gløgård, Christian ; Klaveness, Jo ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 493-496

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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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Structure refinement and Raman spectrum of silver azide (1999)

Guo, Guo-Cong ; Wang, Quan-Ming ; Mak, Thomas C.W.

Springer

Journal of chemical crystallography 29 (1999), S. 561-564

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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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Structure of adamantan-1-ammonium 1-adamantanecarboxylate (1999)

Mullica, Donald F. ; Scott, T. Gordon ; Farmer, J. Matt ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 845-848

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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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Structural characterization of a series of cyclohexaphosphates: M0.5((C6H5CH2)2NH2)5P6O18·H2O (M = Co, Cu, Cd) (1999)

Abid, S. ; Rzaigui, M. ; Bagieu-Beucher, M.

Springer

Journal of chemical crystallography 29 (1999), S. 891-899

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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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The structural characterization of YbI2(DME)3 (1999)

Hibbs, David E. ; Jones, Cameron ; Richards, Anne F.

Springer

Journal of chemical crystallography 29 (1999), S. 1107-1110

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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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Crystal structure of phenyl-substituted cyclopentenes (1999)

Benetollo, Franco ; Busetti, Vilma ; Marcuzzi, Franco

Springer

Journal of chemical crystallography 29 (1999), S. 1127-1132

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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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Self-assembly in transition metal complexes: structural characterization of a copper histamine nitrate [Cu(II)(him)2(NO3)2] (1999)

Zhang, Cun-Gen ; Duan, Chun-Ying ; Hu, Qiao ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1153-1155

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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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14-Hydroxy-14-phenyldibenzo[a,j]xanthene as a lattice host: crystal and molecular structure of its (1:1) complex with diethyl ether (1999)

Barton, Benita ; Caira, Mino R. ; McCleland, Cedric W. ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 1179-1186

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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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Digitale Medien

Synthesis, crystal structure and properties of square-planar acetato{[(4-methylimidazol-5-yl)methylene]histamine} copper(II) perchlorate (1999)

Long, La-Sheng ; Tong, Ye-Xiang ; Chen, Xiao-Ming ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 409-412

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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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Crystal and molecular structure of the symmetrical bidentate ligand 3,3-di(1-pyrazolyl)pentane, CH3CH2C(C3H3N2)2CH2CH3 (1999)

Churchill, Melvyn Rowen ; Churchill, David George ; Huynh, My Hang Vo ; [weitere]

Springer

Journal of chemical crystallography 29 (1999), S. 463-467

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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

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Crystal structure and conformation of frentizole, [1-(6-methoxy-2-benzothiazolyl)-3-phenylurea, an antiviral agent and an immunosuppressive drug (1999)

Rooth, Walter ; Srikrishnan, Thamarapu

Springer

Journal of chemical crystallography 29 (1999), S. 1187-1192

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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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Crystal structure of quinestrol hemiethanolate (1999)

Steiner, Thomas

Springer

Journal of chemical crystallography 29 (1999), S. 355-358

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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

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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)

Kang, Bei-Sheng ; Wen, Ting-Bin ; Yu, Xiang-Yang ; [weitere]

Springer

Journal of cluster science 10 (1999), S. 429-443

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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

Thermal Decomposition Mechanism and Thermodynamic Properties of [Cd(NTO)4Cd(H2O)6]·4H2O (1999)

Song, J. ; Hu, R. ; Kang, B. ; [weitere]

Springer

Journal of thermal analysis and calorimetry 55 (1999), S. 797-806

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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

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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)

Bachechi, Fiorella ; Polcaro, Chiara

Springer

Structural chemistry 10 (1999), S. 135-148

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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

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Survey of Chalcogenide Superconductors (1999)

Nagata, S. ; Atake, T.

Springer

Journal of thermal analysis and calorimetry 57 (1999), S. 807-821

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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

Thermal Decomposition Mechanism, Thermodynamical and Quantum Chemical of Properties [Pb(NTO)2⋅(H2O)] (1999)

Jirong, S. ; Zhaxou, C. ; Rongzu, Hu ; [weitere]

Springer

Journal of thermal analysis and calorimetry 58 (1999), S. 257-267

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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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Synthesis of a Novel Nickel(II) Complex with Dithiocarbimate from Sulfonamide (1999)

Oliveira, Marcelo R. L. ; Graúdo, José E. J. C. ; Speziali, Nivaldo L. ; [weitere]

Springer

Structural chemistry 10 (1999), S. 41-45

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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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4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone, a Nicotine-derived Carcinogenic Nitrosaminoketone (NNK): Three-dimensional Structure (1999)

Katz, Amy K. ; Carrell, H. L. ; Afshar, Carol E. ; [weitere]

Springer

Structural chemistry 10 (1999), S. 439-443

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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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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)

Mentzafos, D. ; Mavridis, I.M. ; Yannakopoulou, K.

Springer

Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 321-330

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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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Recent advances in the structure and function of isopenicillin N synthase (1999)

Kreisberg-Zakarin, Rachel ; Borovok, Ilya ; Yanko, Michaela ; [weitere]

Springer

Antonie van Leeuwenhoek 75 (1999), S. 33-39

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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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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)

Zhu, Naijue ; Harrison, Allen ; Trudell, Mark L. ; [weitere]

Springer

Structural chemistry 10 (1999), S. 91-103

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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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Crystal Structures of Cs+-Crown Ether Complexes Containing Polynuclear Mercury Iodide Anions (1999)

Zhou, Zhixian ; Han, Hongna ; Li, Tiesheng ; [weitere]

Springer

Structural chemistry 10 (1999), S. 177-185

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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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Studies on (Hg0.7Mo0.3)Sr2(Sr1−xLax)Cu2Oz with a Wide Range of Doping State (1999)

Kandyel, Elsayed

Springer

Journal of superconductivity 12 (1999), S. 403-408

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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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X-Ray Crystal Structure of Four Inclusion Complexes of the Novel Host Gossindane: An Oxidation Product of Gossypol (1999)

Talipov, S.A. ; Ibragimov, B.T.

Springer

Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 27-38

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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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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)

Yang, Xinhao ; Craig, Donald C. ; Kumar, Aresh ; [weitere]

Springer

Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 135-148

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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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Ditopic Calixcrowns with Inequivalent Crown Loops: Synthesis and Structural Characterisation of an Unsymmetrical Calix[4]arene biscrown-6 (1999)

Asfari, Zouhair ; Nicolle, Xavier ; Vicens, Jacques ; [weitere]

Springer

Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 251-262

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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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Crown Ether-Dinitrile Interaction: An X-ray Study (1999)

Dalley, N. Kent ; Lamb, John D. ; Nazarenko, Alexander Y.

Springer

Journal of inclusion phenomena and macrocyclic chemistry 33 (1999), S. 331-338

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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

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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)

Zhou, Zhixian ; Xing, Yanjun ; Wu, Yangjie

Springer

Journal of inclusion phenomena and macrocyclic chemistry 34 (1999), S. 221-233

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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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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)

Jones, Peter G. ; Kuś, Piotr

Springer

Journal of inclusion phenomena and macrocyclic chemistry 34 (1999), S. 267-276

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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

Structural Study of C-undecylcalix[4]resorcinarene Solvate with Dioxane (1999)

Borowia, Teresa ; Mączyński, Marek ; Pietraszkiewicz, Marek ; [weitere]

Springer

Journal of inclusion phenomena and macrocyclic chemistry 35 (1999), S. 131-138

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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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An investigation of the nervous system as a possible factor in the regulation of ciliary activity of the lamellibranch gill (1931)

Lucas, Alfred M.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 147-193

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Certain variations of ciliary activity in the lamellibranch gill occur which are an intrinsic part of the gill tissue and which are due to causes other than environmental changes. Experimental and morphological evidence indicates that the central nervous system is not involved in the production of these variations.A comparative study of laterofrontal and lateral ciliated cells leads to the conclusion that the coordination impulse passes through the cytoplasm of the cell and that the velocity of the propagation wave is influenced by the number of cell walls per unit length through which it passes. It is suggested that the ciliary rootlets in the laterfrontal cells, due to their arrangement bring the impulse simultaneously to both rows of cilia within a single cell.

Zusätzliches Material: 5 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510104

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81

Digitale Medien

The spermiogenesis of Succinea ovalis say, with special reference to the components of the sperm (1931)

Hickman, Cleveland P.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 243-289

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: An investigation of the spermiogenesis of Succinea ovalis Say, a small terrestrial pulmonate, has revealed: 1) The germ cells are differentiated from indifferent germinal epithelial cells. In this form the germinal epithelium is a true epithelium, and not a syncytium. 2) Forty chromosomes are found in the spermatogonial divisions and twenty in the maturation divisions. 3) Early in spermiogenesis the proximal centriole penetrates through the spermatid nucleus and, with the oxychromatin, forms an intranuclear rod similar to that reported for certain prosobranches. The homology and significance of the rod are discussed. 4) Of the cytoplasmic structures, the mitochondria and the Golgi apparatus were followed through all stages of spermatogenesis. 5) At the maturation divisions the mitochondria are grouped into peculiar. thread-like structures. Some of the mitochondria take part in the formation of the sheath around the axial filament of the spermatozoon, while the remainder are sloughed off with the cytoplasmic remnant. 6) The Golgi apparatus consists of a number of banana-shaped rods closely grouped around the idiosome. Three to five Golgi rods are found in the spermatid stages. A portion of the Golgi apparatus and idisome (acroblast) forms the acrosome, and the Golgi remnant is discarded at the end of spermatogenesis. 7) In mature sperm both head and tail have a spiral structure. The origin and nature of the spirals are pointed out.

Zusätzliches Material: 2 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510107

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82

Digitale Medien

Blood formation in the african lungfish, under normal conditions and under conditions of prolonged estivation and recoveryThis paper was awarded the Virginia Academy of Science research prize for 1930. (1931)

Jordan, H. E. ; Speidel, C. C.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 319-371

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The blood cells of the African lungfish, Protopterus ethiopicus, are very large and resemble those of urodeles. Leucocytes are especially plentiful and rich in variety, including eosinophils, special eosinophils, [meta-eosinophils] with atypical granules, monocytes, thrombocytes, lymphocytes, and basophils.The chief hemocytopoietic organs are the spleen, intestine, and kidneys. The lungfish spleen, embedded in the wall of the stomach, represents an intermediate phylogenetic stage between the disperse intra-enteral type of the hagfish and the compact extra-enteral type of other vertebrates.Erythrocytes are formed in the spleen pulp, granulocytes in the granulocytopoietic organ of the intestine and in the capsules of kidneys, gonads, and spleen. Thrombocytes and monocytes are differentiated in the spleen and general circulation. Basophils arise in the spleen and intestine. Lymphoid cells of all types arise in the spleen. Evidence is presented bearing upon the hemocytopoietic capacity of the various types. Cells with [Russell bodies] also occur in the spleen.In lungfishes subjected to long periods of dry estivation, erythrocytopoiesis practically ceases. Granulocytes, however, appear to play an important rǒle, possibly in fat metabolism. The large variety of meta-eosinophils, a unique feature of the lungfish, appears to be associated with the habit of estivation.Recovery from estivation may show numerous amitoses of erythrocytes in the general circulation. Other cells which divide in this manner are young thrombocytes, granulocytes, monocytes, and lymphoid hemoblasts.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510203

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83

Digitale Medien

Notes on the postnuclear, acrosome-seat granules, and ‘vacuome’ in Desmognathus fusca spermatogenesis (1931)

Gatenby, J. Brontë

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 597-612

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The acrosome in Desmognathus, Spelerpes, Plethodon, salamander, Amphiuma, etc., is attached to the nucleus in connection with an acrosome seat, which forms a shallow cup, traced back to a number of granules in the early spermatid. A postnuclear plate is present in the above-mentioned urodeles, and is derived from a small number of minute granules which assemble in the spermatid and become fixed onto the nuclear membrane. The centrosomes of the spermatid are visible intravitam. The ‘vacuome’ is formed of minute neutral-red-staining globules embedded in the idiozome. No connection appears to exist between mitochondria and Golgi bodies, as is postulated by the vacuome-chondriome hypothesis (Parat).

Zusätzliches Material: 15 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510209

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84

Digitale Medien

Studies on the comparative histology of the digestive tube of certain teleost fishes II. A minnow (Campostoma anomalum)Studies from the Department of Zoölogy, The University of Nebraska, no. 168. (1931)

Rogick, Mary Dora

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 1-25

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: This paper presents a study of the normal histology of the digestive tract of an herbivorous teleost, the minnow Campostoma anomalum (Raflnesque). The tunics of the buccal cavity, pharynx, esophagus, and intestine are described; particular attention is given to the mucosa because of the specializations occurring in that coat, such as taste buds, goblet cells, callous pad, etc. Because of the very decided anatomical and histological differences existing between the anterior and posterior regions of the pharynx, due to the presence of a callous pad and pharyngeal teeth, it has been deemed advisable to consider the pharynx as divisible into an anterior and a posterior region. Thyroid tissue was found in the submucosa of the anterior pharynx. No gastric epithelium was demonstrated, the ‘intestinal bulb,’ the only enlargement of the coelomic portion of the digestive tube, being lined with epithelium presenting only minor differences from that found in the coiled tubular intestine.

Zusätzliches Material: 6 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520102

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85

Digitale Medien

The history of the germ cells in the viviparous teleost platypoecilus maculatus (1931)

Wolf, Louis E.

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 115-153

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: This study is based upon a series of ontogenetic stages from just before coelom formation to maturity.Primordial germ ceils are first seen at the outer edge of the lateral mesoderm and are traced from there to a position in the genital analagen. Counts indicate that most of them succeed in reaching the genital anlagen, where they from definitive reproductive cells in both sexes.The evidence seems to show that there is some transformation of somatic cells into germ cells in the immature female, but that this transformation is not extensive. In the male the primordial germ cells are the sole source of the definitive elements.

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520106

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86

Digitale Medien

The development of the carp, cyprinus carpio. I. The larval life of the carp, with special reference to the development of the intestinal canal (1931)

Smallwood, W. M. ; Smallwood, Mary Lovett

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 217-231

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The detailed spawning habits and hatching period are described. The larval period is divided into the inactive, when the yolk is the source of food, and the active period, when food is captured. The rate of growth and transformation of the larvae into fry is described.The cell formation passes into a syncytial period, when there are produced many nuclei without cytoplasm.c division. Around these nuclei, the cytoplasm collects to give rise to more cells. The method by which mucous cells are produced is described and also the presence of secretion masses in both the mucous cells and the syncytium of the mucosa.

Zusätzliches Material: 7 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520110

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87

Digitale Medien

The development and the regeneration of the color pattern in brachydanio rerio (1931)

Goodrich, H. B. ; Nichols, Rowena

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 513-523

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The teleost fish Brachydanio rerio is strikingly marked with longitudinal black stripes, which extend into the caudal fin and across the anal fin. Removal of the anal fin is followed by complete regeneration of the fin and of its normal color pattern. Microphotographic studies show that melanophores are at first uniformly distributed in the regenerating tissue and that later the melanophores disintegrate in the zone of the future light stripe and increase in the region of the future dark stripe. Observations on the normal development of the fin where the history of the individual melanophores has been followed show the same mode of formation of the stripes.

Zusätzliches Material: 2 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520207

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88

Digitale Medien

Masthead (1931)

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931)

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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.1050510101

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89

Digitale Medien

History of the germ cells in Sphaerium striatinum (Lam.) (1931)

Woods, Farris H.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 545-595

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Study of living and sectioned material throughout the life cycle shows the germ-cell history from fertilized egg to sexual maturity. This can be divided into the following five periods with definite limits: Original appearance during cleavage, period of inactivity, period of multiplication, maturation, and fertilization. Primordial germ cells of characteristic structure can be recognized just before gastrulation, when there is one large germ cell in the mass of mesoderm on either side of the blastocoel. After one division in each of these two cells, the four daughter cells remain inactive, while the remainder of the mesoderm differentiates, until division is resumed in the developing gonad. An indefinite number of gametes is produced. All are direct descendants of the two original primordial germ cells. Transformation of somatic cells into germ cells does not occur nor do germ cells become somatic cells. Cell lineage shows the two primordial germ cells to be derived from the third division of the paired mesoderm cells which have arisen by an equal division of the fourth micromere produced by cell D of the four-cell stage. Details of meiosis have not been ascertained, because of the small size of the chromosomes, their large number, and the difficulty of fixation. Nothing forecasts which primordial germ cells will become ova and which spermatozoa.

Zusätzliches Material: 54 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510208

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90

Digitale Medien

Cytoplasmic structures in binucleate opalinids, with special reference to the Golgi apparatusThis investigation was carried out with the aid of the Cancer Research and Treatment Fund. (1931)

Richardson, K. C. ; Horning, E. S.

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 27-45

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Three types of cell inclusions are demonstrated within the general protoplasm of the binucleated Protoplina, parasites of Hyla aurea. These are considered to represent mitochondria, together with associated, synthesized vegetative granules and Golgi bodies, as evidenced by their behavior, morphology, and staining reactions.The Golgi material is shown to consist of irregularly twisted rods and granules scattered at random in the cytoplasm, but possessing a very distinctive morphology and reaction to different techniques when compared with the mitochondria. No relationship could be detected between these vegetative structures and the cilia, as has been previously described.These observations have also been extended to a similar study of the cytoplasmic organs of Nyctotherus cordiformis, and it has been possible to demonstrate Golgi bodies of a similar appearance within this organism as well as to show again the nature of the basal granules and their relationship to the cilia.The procedure of identifying the mitochondria elements with great care is recommended as a preliminary means of studying the Golgi apparatus of Protozoa, particularly where osmication techniques are used exclusively.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520103

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91

Digitale Medien

The intranuclear deutoplsmThe terms deutoplasm and yolk are used in this paper, as they seem to be generally used by turbellarian workers, to denote material that is used as food material by the developing organism and which, with ordinary stains and technique, reacts like yolk. It should be understood that no specific chemical tests for yolk have been empolyed in this work. and the origin of gametes in the turbellarian Prorhynchus applanatus Kennel (1931)

Jones, E. Ruffin

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 233-247

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: It is shown that in Prorhynchus applanatus there exists a type of yolk elaboration which has hitherto not been reported. Formation is within the nucleus through the growth and fusion of nucleoli, but the yolk globule becomes larger than the original nucleolus. The developing individual utilizes the food material contained in the yolk cells in the following order: (1) cytoplasm of the yolk cell, (2) yolk bodies contained in this cytoplasm, (3) intranuclear yolk, (4) nucleoplasm. It is also shown that the germ cells in this form arise from the endoderm by diapedesis, but that the yolk cells are mesenchymal in origin. The sequence of formation of male and female gametes precludes the possibility of the presence of sex hormones such as are found in higher forms.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520111

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92

Digitale Medien

A comparative study of the chromosomes of rodentsContribution from the Department of Zoölogy, University of Texas. This work was done under the direction of Dr. T. S. Painter, to whom the writer wishes to express his obligation and appreciation. (1931)

Cross, James Cecil

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 373-401

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: A comparative study has been made of fifteen species and subspecies of rodents to determine the range in number and variation in morphology of their chromosomes. The number range is between 40 and 86±, with an average number for known species of 52. In the family of Cricetidae there is little variation in chromosome number and a general similarity of the chromosomes. In the Muridae the range for known species is 40 to 42, but the chromosome morphology even of subspecies may be quite different. In Sciuridae a range of 48 to 62 has been found in different species. The greatest range in number is found in the Heteromyidae, 44 and 86± chromosomes having been found in two species. It is concluded that the stem number for rodents is close to 48 and that fragmentation and fusion account for variation in numbers, and these affect the morphology of the chromosomes. The evidence also indicates that variations in morphology are due to translocations and inversions, and possibly deletions accompanied by translocations.

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520203

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93

Digitale Medien

The distribution of sperm-forming materials in scorpions (1931)

Wilson, Edmund B.

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 429-483

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: There are in scorpions two sharply contrasting types in respect to the mode of distribution of the chondriosomes to the sperm cells. In one of these the chondriosomes, spheroidal in form and nearly definite in number, are sorted out whole without division during the spermatocyte divisions, their number being thus reduced successively to one-half and one-fourth. This type occurs in Opisthacanthus, Hadrurus, Vejovis, Euscorpius, and Palamnaeus. In the other, as yet known only in Centrurus, all the chondriosomes fuse during the spermatocyte growth period to form a single ring-shaped body; and this, during the two ensuing mitoses, is accurately divided into two, four, and eight equal parts, of which each spermatid receives two. In both types alike the chondrioma is thus distributed very nearly equally to the sperm cells, but by widely contrasting processes; and in both types the spermatid chondriosomes are drawn out to form the sheath of the axial filament in the sperm tail. In Opisthacanthus there are indications of a definite process of dictyokinesis during the spermatocyte divisions.These facts are discussed in the light of the general history of the chondriosomes in other animals, with especial reference to more general problems of cell division. The present vagueness and uncertainty of our knowledge of cell division and differentiation are emphasized.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520205

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94

Digitale Medien

Polymorphism among the subgenera of nasutitermes (1931)

Hare, L.

New York, NY : Wiley-Blackwell

Journal of Morphology 52 (1931), S. 593-607

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: This study is concerned with the interrelationship existing among the polymorphie soldier castes of six representative subgenera of the genus Nasutitermes. By measurements of anatomical parts and camera-lucida drawings, an attempt has been made to compare these particular subgenera on a basis of gradual divergence of certain structures. For this purpose a series of tables was compiled in which apparently unstable structures were compared to a relatively stable figure in all available species of the selected subgenera.According to my findings, it was concluded that there is no strict correspondence between the major, intermediate, and minor castes of different subgenera of the genus Nasutitermes. Particular reference is made to the work of N. Holmgren ('12) and to that of J. S. Huxley on heterogonic growth.

Zusätzliches Material: 4 Tab.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050520211

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95

Digitale Medien

The distribution of the branchial nerve in Mytilus edulis and its relation to the problem of nervous control of ciliary activity (1931)

Lucas, Alfred M.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 195-205

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Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The branchial nerve of Mytilus edulis, traced by means of serial sections, has been found to be limited entirely to the epithelial and connective tissues bordering the axis of the gills. Most of the numerous branches which originate from the branchial nerve extend posteriorly and lie close to the interfibrillar matrix of the connective tissue which supports the epithelium of this region. Fibers of these nerves have been traced to this epithelium.The chitinous supporting structures of the gills lie in close proximity to these nerves, yet neither nerves nor nerve fibers have been observed to penetrate them. Moreover, a careful study of the gill tissues fails to reveal the presence of structures which might be interpreted as nerves or nerve fibers.Since no innervation of the gills has been demonstrated, it seems probable that the ciliary activity of the gill epithelium is not regulated by means of fibers connected with the central nervous system.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510105

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96

Digitale Medien

The morphology of Spironympha, with a description of a new species from reticulitermes hesperus Banks (1931)

Brown, George V. E.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 291-307

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Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Spironympha is discussed as valid genus. It was described by Koidzumi ('16); later it was redescribed by the same author as Microspironympha ('21). Therefore, according to the rules of nomenclature, it is Spironympha.The genus is compared with the related genera: Spirotrichonympha, Holomastigotes, and Microjoenia.Spironympha is characterized by four flagellar bands which are spirally wound around the anterior part of the body; these bands occur only in the anterior end, whereas in Spirotrichonympha they extend almost to the posterior end. The parabasals are few in number, and they are attached to the basal granules of the flagellar bands; the anterior end is clear and almost free from cytoplasmic granules; and there are twenty to thirty anterior flagella which are attached to the base of the centroblepharoplast or to the basal granules of the flagellar bands. An axostyle is present.No centrosome occurs within the nucleus, but the centroblepharoplast has this kinetic function.Spironympha ovalis is described as a new species. It is ovoid; the average size is 38 μ to 44 μ. An axostyle is present. The host is Reticulitermes hesperus Banks.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510108

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97

Digitale Medien

The embryogeny of the Polyctenid, Hesperoctenes fumarius Westwood, with reference to viviparity in insects (1931)

Hagan, Harold R.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 1-117

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Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Four functional types of viviparity are recognized, and the last, pseudoplacento viviparity, is illustrated by a review of the embryogeny of a species of Polyctenidae. This insect normally has ten embryos in the reproductive tract in successive stages of development. The problem of fertilization is discussed, for there seems to be no spermatheca and spermatic clumps are present in the haemocoel. No organ of Berlese can be found. One, apparently a nymph, when sectioned revealed spermatozoa in even greater abundance than the mature females. Four to six of her offspring would seem to be paedogenetic.Females liberate ova that are yolk-free, and no chorion is secreted about them. Blastomeres are distinct, the embryonic envelopes are formed as usual, and hemipteran embryology occurs. The trophserosa functions until blastokinesis takes place, when the pleuropodial extensions evaginate and encompass the embryo which now lies in a pleuropodial cavity. The pleuropodia function as Lutrient organs, or psedoplacenta, until shortly before birth. At birth the embryo is a little more than one-third the adult body length and bears strongly developed setae.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510102

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Digitale Medien

The labyrinth of bufo vulgaris japonicus larva. Especially, upon the morphologic study of the perilymphatic space, in connection with the membranous labyrinth and auditory capsule (1931)

Amano, Kageyas W.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 207-242

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: A morphologic study of the labyrinth, especially on the perilymphatic space with its physiologic aspect, is presented in this paper. The perilymphatic space starts its development with the chondrification of the auditory capsule, and is completed by the end of the first third of metamorphosis. The author divides the whole spatium into two parts: the ductus perilymphaticus et diverticula and the pars spongiosa spati perilymphatici. The ductus perilymphaticus et diverticula may play an important rǒle in carrying out the functions of both equilibrium and audition. The pars spongiosa serves not only to fasten the membranous labyrinth to the capsular wall, but acts as a safeguard for the functions of both the membranous labyrinth and the ductus perilymphaticus et diverticula. The ductus system may have more important physiologic relations than does the membranous labyrinth in connection with the cranial cavity and spinal cord, as to the change of pressure, the transmission of vibrations, the osmosis of fluids, etc. A number of microscopic and schematic figures are shown with reference to the anatomic and morphologic relations of the membranous labyrinth, auditory capsule, and spatium perilymphaticum.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510106

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99

Digitale Medien

Observations on the ‘renal-portal’ perfusion in etherized birds (1931)

Das, B. K.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 309-318

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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 made to demonstrate the direction of the current of a perfusing fluid (hence that of blood in nature) inside the so-called [renal-portal] vein of birds and to determine if this vein has any fine capillaries in the kidney substance. A domesticated male duck was anaesthetized with ether, and a warm saline (mixed with a little urea and urine) was passed through the aorta. The [renal-portal] vein was also perfused with the same fluid through the left internal iliac vein. At first the kidneys actively secreted semisolid urine, but gradually the strength of the latter varied from a milky to a watery fluid.Later, a warm carmine solution was perfused through the left internal iliac vein, and the path of the dye could be easily traced along the whole length of the left renal afferent (left [renal-portal] vein) and its final exit through the postcaval vein. The posterior lobe of the left kidney was partially tinged with red, probably due to diffusion, since the kidney substance should have taken a uniform red hue if there was any definite capillary system. The coccygeomesenteric vein contained no dye.These results (coupled with actual caliber measurements of the two [renal-portal] veins in duck and pigeon examined, the calibers of these veins increasing gradually posteroanteriorly) indicate that: 1) blood flows anteriorly in the [renal-portal] vein; 2) this vein does not break up into capillaries in the kidney substance, but receives larger affluent veins; 3) there is no [renal-portal] system in birds; 4) the urine secreted by birds is always semisolid.

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510202

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100

Digitale Medien

Life cycle, sex differentiation, and testis development in Melanoplus differentialis (Acrididae, Orthoptera) (1931)

Nelsen, Olin E.

New York, NY : Wiley-Blackwell

Journal of Morphology 51 (1931), S. 467-525

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ISSN: 0362-2525

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: The general morphological and histological evidence accumulated by this study suggests the following facts: 1Under out-of-door conditions, in the vicinity of Philadelphia, Pennsylvania, embryonic development begins at deposition and continues to the middle or late spring, when hatching occurs. The postembryonic development is completed during the summer. Copulation and oviposition occur in the late summer and early fall.2The embryonic development may be divided as follows: aThe prerevolution period, in which the rudiments of organs and systems are formed.bThe early-revolution period, during which the direction of the embryo in the egg is reversed.cThe late-revolation period, or time of yolk circumcrescence and completion of the dorsal wall of the embryo.dThe postrevolution period. comprising development from yolk engulfment to hatching.3The sexes are differentiated during the early- and late-revolution periods.4In the differentiation of the genital rudiments, a) the germ cells are segregated into groups; b) and indifferent mesodermal element grows in among the germ cells of such a group; c) the processes of this cell (the apical cell) form intimate connections with the processes of connective-tissue elements surrounding the germ-cell group; and, d) the covering membrane of the genital rudiment grows in between the various germ-connective-tissue cell groups, completing the rudiment of the follicle.5When the adult condition is reached the testis is functionally differentiated.

Zusätzliches Material: 2 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jmor.1050510206

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