Preferred conformation and dynamics of the glycerol backbone in phospholipids. An NMR and x-ray single-crystal analysis

Biochemistry ◽  
1988 ◽  
Vol 27 (26) ◽  
pp. 9166-9174 ◽  
Author(s):  
H. Hauser ◽  
I. Pascher ◽  
S. Sundell
Keyword(s):  
Single Crystal ◽  
Glycerol Backbone ◽  
X Ray ◽  
Single Crystal Analysis

The modulated structure of the calcium aluminate Ca6(AlO2)12·Bi2O3

2010 ◽  
Vol 66 (6) ◽  
pp. 585-593 ◽  
Author(s):  
O. Pérez ◽  
S. Malo ◽  
M. Hervieu
Keyword(s):  
Single Crystal ◽  
Calcium Aluminate ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
Electron Pairs ◽  
Modulated Structure ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Superspace Formalism ◽  
Single Crystal Analysis

Bismuth calcium aluminate, Bi2Ca6Al12O27, has been prepared as a ceramic and a single crystal. Analysis of reciprocal space using both electron and X-ray diffraction show an R-centred hexagonal unit cell: a = b = 17.3892 (4), c = 6.986 (1) Å. Additional weak reflections are observed; they require the introduction of a modulation wavevector q = 0.0453 (2)c* for indexing. The modulated structure has been solved using the superspace formalism [superspace group X\overline{3}(00\gamma)0]. A framework of corner-sharing AlO4 tetrahedra forms corrugated sixfold rings and uncommon triple rings. The Ca2+ cations exhibit an eightfold coordination sphere; edge-sharing CaO8 polyhedra form intertwinned zigzagging rows along c creating a three-dimensional net. Bi atoms are located in large hexagonal tunnels parallel to c and form Bi2O3 pairs, which adopt a trigonal bipyramidal configuration. The 6s 2 lone-electron pairs (Lp) point along c, in the opposite direction to the three Bi—O strong bonds to form two BiO3Lp tetrahedra with a common base. Different orientations of the Bi2O3Lp2 pairs, rotated by 60° around c, are observed. Their stacking modes in each of the hexagonal tunnels are described. The sequence of the stacking varies along c in each of the tunnels.

X-ray single crystal analysis of the phase transitions in NH4MnCl3. Some Mossbauer-X-ray spectra relations

1978 ◽  
Vol 19 (1) ◽  
pp. 123-130 ◽  
Author(s):  
J. D. Tornero ◽  
F. H. Cano ◽  
J. Payos ◽  
M. Martinez-Ripoll
Keyword(s):  
Phase Transitions ◽  
Single Crystal ◽  
X Ray ◽  
Single Crystal Analysis

scholarly journals X-Ray Single Crystal Analysis of Oligo(oxymethylene) Diacetates

1993 ◽  
Vol 25 (12) ◽  
pp. 1275-1281 ◽  
Author(s):  
Koichi Ute ◽  
Takehito Takahashi ◽  
Ken-ichi Matsui ◽  
Koichi Hatada
Keyword(s):  
Single Crystal ◽  
X Ray ◽  
Single Crystal Analysis

The Preparation of 1,2-Bis(2,2′:6′,2′′-Terpyridin-4′yl)Ethanone: The First Example of 4′-Terpyridyls Unsymmetrically Linked by a Functionalized Two-Carbon Chain

2004 ◽  
Vol 57 (7) ◽  
pp. 689 ◽  
Author(s):  
Zhi-Long Chen ◽  
Ronald N. Warrener ◽  
Douglas N. Butler
Keyword(s):  
Sulfuric Acid ◽  
Hydrochloric Acid ◽  
Single Crystal ◽  
Coupling Reaction ◽  
Carbon Chain ◽  
Sodium Cyanide ◽  
Starting Material ◽  
X Ray ◽  
Concentrated Sulfuric Acid ◽  
Single Crystal Analysis

1,2-Bis(2,2′:6′,2′′-terpyridin-4′yl)ethanone 7, an unsymmetrically linked bis-tridentatate ligand, was prepared by treatment of 4′-cyanomethylterpyridine 10 (RT, overnight) or 4′-(methoxycarbonylmethyl)terpyridine 11 (60°C, 7 h) with concentrated hydrochloric acid. These conversions, which involved an unprecedented homo-coupling reaction, are discussed with the structure of 7 being confirmed by X-ray single crystal analysis. The nitrile starting material 10 was prepared by reaction of the mesylate 9, derived from the known 4′-hydroxymethylterpyridine 8 with sodium cyanide, while ester 11 was prepared by reaction of 10 with methanol in the presence of concentrated sulfuric acid.

5-Allyl-9-oxobenzomorphans. Part 2. The Crystal and Molecular Structure of an Unusual Product of Dequaternization of 5-Allyl-9-oxobenzomorphan Methobromide

1975 ◽  
Vol 53 (21) ◽  
pp. 3276-3284 ◽  
Author(s):  
Farid R. Ahmed ◽  
Michel Saucier ◽  
Ivo Monković
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Methoxy Derivative ◽  
X Ray ◽  
Unusual Product ◽  
Single Crystal Analysis

The synthesis of 5-allyl-2'-methoxy-9-oxo-6,7-benzomorphan (5b) is described. The 10-hydroxy-2-methyl-1,11-propano-9H-indeno-1,2,10,11-tetrahydro[2,1-c]pyridine (7a) and the corresponding 6-methoxy derivative (7b) are unexpected products of pyrolysis of 5-allyl-2-methyl-9-oxobenzomorphan methobromide (4a) and 5-allyl-2′-methoxy-2-methyl-9-oxobenzomorphan methobromide (4b) respectively. The molecular structure of 7a (C16H19NO) has been determined from spectral and microanalytical data, and confirmed by X-ray single crystal analysis on its hydrobromide salt using the heavy atom technique. The crystals of [C16H20NO]+Br− are monoclinic, P21/a, with a = 13.724(2), b = 14.022(3), c = 7.495(2) Å, β = 97.33(5)°, and Z = 4. The crystal structure has been refined by block-diagonal least-squares calculations to R and Rw = 0.036 for the 2197 observed reflections. The N atom has planar trigonal coordination, and forms one double and two single C—N bonds of lengths 1.273(4), 1.465(4), and 1.474(4) Å, respectively. The Br is hydrogen-bonded to O. The N and O atoms are trans.

scholarly journals Synthesis of mesomeric betaine compounds with imidazolium-enolate structure

2012 ◽  
Vol 8 ◽  
pp. 390-397 ◽  
Author(s):  
Nina Gonsior ◽  
Fabian Mohr ◽  
Helmut Ritter
Keyword(s):  
Ir Spectroscopy ◽  
Single Crystal ◽  
Inclusion Complexes ◽  
Polymer Networks ◽  
Reaction Conditions ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Single Crystal Analysis

The synthesis of a heterocyclic mesomeric betaine by quaternization reaction of 1-butylimidazole and tetrabromo-1,4-benzoquinone is presented. The structure was verified by means of X-ray single-crystal analysis, NMR and IR spectroscopy. Inclusion complexes of the heterocyclic mesomeric betaine with randomly methylated (1.8) β-cyclodextrin were investigated by UV–vis spectroscopy. Furthermore, the reaction conditions were applied to poly(vinylimidazole) and 1,4-bis(1H-imidazol-1-yl)butane to obtain functionalized polymer networks and condensate polymers, respectively.

Fe(III)–azido complex with tetragonally compressed octahedral FeN6 geometry: synthesis, spectroscopic and X-ray single crystal analysis of [Fe(cyclam)(N3)2](ClO4)

Polyhedron ◽  
1999 ◽  
Vol 18 (16) ◽  
pp. 2201-2204 ◽  
Author(s):  
Subratanath Koner ◽  
Seiichiro Iijima ◽  
Fumio Mizutani ◽  
Kazuaki Harata ◽  
Masanobu Watanabe ◽  
...  
Keyword(s):  
Single Crystal ◽  
X Ray ◽  
Single Crystal Analysis

scholarly journals X-ray Single-Crystal Analysis of Na2H[(P0.52As0.48)O4]·7H2O

2011 ◽  
Vol 27 ◽  
pp. 29-30
Author(s):  
Nasreddine ENNACEUR ◽  
Khaled JARRAYA ◽  
Isabelle LEDOUX-RAK ◽  
Nicolas GUIBLIN ◽  
Tahar MHIRI
Keyword(s):  
Single Crystal ◽  
X Ray ◽  
Single Crystal Analysis
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