Molecular design to mimic the copper(II) transport site of human albumin. The crystal and molecular structure of copper(II) – glycylglycyl-L-histidine-N-methyl amide monoaquo complex

1976 ◽  
Vol 54 (8) ◽  
pp. 1309-1316 ◽  
Author(s):  
Norman Camerman ◽  
Arthur Camerman ◽  
Bibudhendra Sarkar
Keyword(s):  
Molecular Structure ◽  
Molecular Design ◽  
Crystal And Molecular Structure ◽  
Human Albumin ◽  
Water Molecules ◽  
Copper Binding ◽  
Amino Terminal ◽  
Square Planar ◽  
Cell Dimensions ◽  
Transport Site

Glycylglycyl-L-histidine-N-methyl amide is a copper-binding tripeptide designed and synthesized to mimic the copper-transport site of human albumin. Reddish-purple crystals of the copper-tripeptide amide complex (Cu–GGHa), grown at physiological pH, are triclinic, with cell dimensions a = 9.990, b = 9.986, c = 7.682 Å, α = 107.40, β = 91.72, γ = 96.49°, space group P1, Z = two units of Cu–GGHa and two water molecules per cell. The structure was solved by interpretation of a Cu–phased Fourier map containing a great deal of false symmetry, after multiple attempts with direct phasing methods failed. Refinement proceeded to R = 0.036. The conformations of the two Cu–GGHa units are virtually identical. Each copper is tetradentate chelated by the amino terminal nitrogen, the next two peptide nitrogens, and a histidyl nitrogen of a single tripeptide molecule in a mildly distorted square planar arrangement. The Cu…N distances range between 1.90–2.05 Å, with N…Cu…N angles of 165 and 176°. An oxygen atom provides a fifth position weaker interaction in each case, with Cu…O distances of 2.61 and 2.88 Å.

3-Methylpyridine complexes of cobalt(II) and nickel(II) hexafluorophosphate and hexafluoroarsenate. Crystal and molecular structure of Ni(H2O)2(3-CH3C5H4N)6(PF6)2

1983 ◽  
Vol 61 (7) ◽  
pp. 1651-1658 ◽  
Author(s):  
Raymond M. Morrison ◽  
Robert C. Thompson ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Hydrogen Atom ◽  
Water Molecule ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Water Molecules ◽  
Magnetic Studies ◽  
Full Matrix ◽  
Mild Conditions ◽  
Square Planar

Reaction of aqueous solutions containing CO2+ or Ni2+ and PF6−, or AsF6− with excess 3-methylpyridine yields crystals of compounds of composition M(H2O)2(3mpy)6(EF6)2. Blue crystals of diaquohexakis(3-methylpyridine)nickel(II) hexafluorophosphate, C36H46F12NiN6O2P2, are monoclinic, a = 10.497(1), b = 20.074(3), c = 21.836(5) Å, β = 103.93(2)°, Z = 4, space group Cc. The structure was determined with MoKα CAD4 diffractometer data by direct methods, and refined by full-matrix least-squares procedures to R = 0.048 for 2723 reflections with I ≥ 3σ(I). The structure consists of {Ni(3mpy)4[(OH2)(3mpy)]2}2+ cations and PF6− anions. The cation contains a NiN4O2 chromophore with water molecules occupying trans positions of a distorted octahedron about nickel. One additional 3-methylpyridine molecule is H-bonded to each of the water molecules with [Formula: see text] distances of 2.717(11) and 2.719(11) Å. Weak interaction of each water molecule via its second hydrogen atom with a PF6− ion is indicated by the positioning of the anions. The [Formula: see text] distances are 2.958(11) and 2.959(11) Å. Two other complexes of this type, where M is Ni and E is As and where M is Co and E is P, are reported here and on the basis of spectroscopic and magnetic studies are assigned structures similar to the Ni/P complex.Decomposition of the aquo complexes under mild conditions yields compounds of composition M(3mpy)4(EF6)2. Ni(3mpy)4(PF6)2 is assigned a square planar structure with weakly interacting PF6−, anions in axial positions. Both Co(3mpy)4(EF6)2 complexes, where E is P or As, have tetrahedral [Co(3mpy)4]2+ cations and non-coordinated anions.

The crystal and molecular structure of streptomycin oxime selenate tetrahydrate

1978 ◽  
Vol 359 (1698) ◽  
pp. 365-388 ◽  
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Hydrogen Atoms ◽  
Glycosidic Bonds ◽  
Compound C ◽  
Cell Dimensions ◽  
Network Of Hydrogen Bonds

The crystal and molecular structure and absolute configuration of the antibiotic streptomycin have been determined by an X-ray study of the hydrated oxime selenate. The compound (C 21 H 40 N 8 O 12 . 1 1/2 H 2 SeO 4 .4H 2 O) crystallizes in the monoclinic space group C 2, with cell dimensions a = 17.10(1), b = 14.36(1), c = 16.13(1)Å∥, β = 108.0(2)°; Z = 4 The structure was solved by the heavy-atom method, by using 3236 visually-estimated intensities, and refined to a conventional R of 0.086. The analysis has confirmed that streptomycin consists of three fragments, an N -methyl- α-L-glucosamine ring, an α-L-streptose and a streptidine ring, linked together by two glycosidic bonds. The crystal structure contains an elaborate network of hydrogen bonds linking selenate and streptomycin oxime ions and water molecules, analysis of which, though somewhat hampered by inability to observe the hydrogen atoms experimentally, reveals a disordered hydrogen bond occurring between two diad-related water molecules.

scholarly journals The Crystal and Molecular Structure of Diazido-2,2′-bipyridinecopper(II)

1974 ◽  
Vol 52 (17) ◽  
pp. 3125-3133 ◽  
Author(s):  
Gordon W. Bushnell ◽  
Masood A. Khan
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bond Lengths ◽  
Square Planar ◽  
Copper Coordination ◽  
Cell Dimensions ◽  
Coordinate Bond

The crystal and molecular structure of diazido-2,2′-bipyridinecopper(II), C10H8N2(N3)2Cu, is determined by single crystal X-ray diffraction, and refined to an R value of 0.067. The cell dimensions are a = 664.9(2), b = 843.3(1), c = 1082.0(2) pm, α = 86.99(2)°, β = 87.77(3)°, γ = 78.59(2)°. The space group is [Formula: see text] (No. 2) with 2 molecules per unit cell and the measured density is 1.71(2) g cm−3. The copper coordination is square planar with two additional longer bonds. The coordinate bond lengths in pm to the bipyridine ligand are: Cu—N(1), 201.6(6); Cu—N(2), 201.9(6). The coordinate bonds to the azido ligands are: Cu—N(3), 194.9(6); Cu—N(6), 196.6(6). The longer bonds are: Cu—N(3)″, 268.0(8), Cu—N(6)′ 268.2(8). The N—N bond lengths within each azido ligand are unequal: N(3)—N(4), 118.2(10); N(4)—N(5), 115.4(11); N(6)—N(7), 119.2(9); N(7)—N(8), 114.8(9). The angles at N(3) and N(6) are both 130° and at N(4) and N(7) the angles are both 175(1)°. Each azide takes part in asymmetric bridging through a single nitrogen atom. The results are compared with other structural studies on azido complexes and to a nitrate complex of Ag(II) which is structurally similar.

The crystal and molecular structure of trans-chloro(3-hydroxypropyl-N,N-dimethylaininocarbene)-bis(dimethylphenylphosphine)platinum(II) hexafluorophosphate

1978 ◽  
Vol 56 (12) ◽  
pp. 1602-1609 ◽  
Author(s):  
Robert F. Stepaniak ◽  
Nicholas C. Payne
Keyword(s):  
Molecular Structure ◽  
Bond Length ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
R Factor ◽  
Square Planar ◽  
Cell Dimensions ◽  
Cation Coordination

The crystal and molecular structure of trans-chloro(3-hydroxypropyl-N,N-dimethylaminocarbene)bis(dimethylphenylphosphine)platinum(II) hexafluorophosphate has been determined from three-dimensional X-ray data collected on an automated four circle diffractometer using CuKα radiation. The compound crystallizes in the orthorhombic space group Pna21, with Z = 4, and cell dimensions a = 14.403(2), b = 12.631(2), and c = 16.151(2) Å. Full matrix least-squares refinement on F gave a final conventional R factor of 0.047 for 3442 observations with I > 3σ(I). The cation coordination geometry is square planar, with the carbene ligand lying approximately perpendicular to the plane. The Pt—Cl bond length is 2.356(4) Å and the Pt—C(carbene) distance is 1.978(12) Å. The C(carbene)—N bond length is 1.293(16) Å. These dimensions are discussed in terms of the trans influences of the carbene and chloride ligands and the bonding in the carbene species.

The crystal and molecular structure of tris(pentamethylenedithiocarbamate) chromium(III)-chloroform (1 : 2)

1981 ◽  
Vol 46 (1) ◽  
pp. 6-19 ◽  
Author(s):  
Viktor Kettman ◽  
Ján Garaj ◽  
Jaroslav Majer
Keyword(s):  
Molecular Structure ◽  
Structural Analysis ◽  
Crystal And Molecular Structure ◽  
Analysis Method ◽  
Complex Molecules ◽  
Coordination Polyhedra ◽  
X Ray ◽  
Cell Dimensions ◽  
Crustal Density ◽  
Unit Cell Dimensions

The crystal and molecular structure of [Cr(S2CN(CH2)5)3].2 CHCl3 was found by the X-ray structural analysis method. The value R 0.090 was found for 1 131 observed independent reflections. The substance crystallizes in a space group of symmetry P212121 with the following unit cell dimensions: a = 0.8675 (6), b = 1.815(2), c = 2.155(3) nm. The experimentally observed crustal density was 1.48 Mgm-3 and the value calculated for Z = 4 was 1.51 Mgm-3. The CrS6 coordination polyhedron has the shape of a trigonally distorted octahedron, where the D3 symmetry is a approximately retained. The degree of trigonal distortion expressed as the projection of the chelate S-Cr-S angle onto the plane perpendicular to the C3 pseudo axis is Φ = 41.7° (Φ = 60° for an octahedron). The skeleton of the structure formed by the complex molecules contains channels filled with chloroform molecules. The specific type of complex-chloroform interaction consists of the formation of hydrogen bonds of the chloroform protons with the fully occupied pπ-orbitals of the sulphur atoms in the coordination polyhedra. The low stability and crystal decomposition can be explained by loss of chloroform from the channels.

scholarly journals The crystal and molecular structure of the bis(N,N,N′,N′-tetramethylethanediamine) adduct of I(Br)InInBr2, In2Br3I•2C6H16N2, an indium–indium bonded molecule

1984 ◽  
Vol 62 (3) ◽  
pp. 601-605 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Orthorhombic Space Group ◽  
Trigonal Bipyramidal ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Distorted Trigonal Bipyramidal

The crystal structure of the title compound has been determined by the heavy atom method. The crystals are orthorhombic, space group Pbca, with unit cell dimensions a = 22.795(3) Å, b = 17.518(2) Å, c = 12.396(3) Å, Z = 8; R = 0.0409 for 1527 unique "observed" reflections. The structure is disordered, with each halogen site (X) occupied by 75% Br, 25% I. The molecule consists of two X2(tmen)In units (tmen = N,N,N′,N′-tetramethylethanediamine) with distorted trigonal bipyramidal geometry, joined by an In—In bond 2.775(2) Å in length.

scholarly journals The Crystal and Molecular Structure of a trans Square-Planar Complex of Tellurium Dimethanethiosulphonate with Thiourea.

1965 ◽  
Vol 19 ◽  
pp. 2361-2368 ◽  
Author(s):  
Olav Foss ◽  
Kjartan Marøy ◽  
Steinar Husebye ◽  
Svein Solheimsnes ◽  
Brita Swan ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Planar Complex ◽  
Square Planar

scholarly journals The Crystal and Molecular Structure of a trans Square-Planar Complex of Tellurium Dibenzenethiosulphonate with Trimethylenethiourea.

1969 ◽  
Vol 23 ◽  
pp. 3206-3216 ◽  
Author(s):  
Kjell Åse ◽  
Georg Lundgren ◽  
Wanda Mark ◽  
Hans Lundström ◽  
Gunner Borch ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Planar Complex ◽  
Square Planar

Stereochemical basis of anticonvulsant drug action. VI. Crystal and molecular structure of diphenylsilanediol

1977 ◽  
Vol 55 (20) ◽  
pp. 3631-3635 ◽  
Author(s):  
J. Keith Fawcett ◽  
Norman Camerman ◽  
Arthur Camerman
Keyword(s):  
Molecular Structure ◽  
Phenyl Ring ◽  
Anticonvulsant Activity ◽  
Crystal And Molecular Structure ◽  
Anticonvulsant Drug ◽  
Drug Action ◽  
Asymmetric Unit ◽  
Triclinic Space Group ◽  
Fourier Methods ◽  
Cell Dimensions

The crystal and molecular structure of diphenylsilanediol, a compound with recently demonstrated anticonvulsant activity, has been determined and its stereochemistry compared with other antiepileptics. Crystals of diphenylsilanediol are triclinic, space group [Formula: see text] with cell dimensions a = 9.912, b = 15.048, c = 14.519 Å, α = 120.83,β = 99.95, γ = 100.84°, Z = 6 molecules per cell (3 molecules per asymmetric unit). The structure was determined by Patterson and Fourier methods and refined to a final discrepancy value R = 0.034. The phenyl ring planes in the molecule are rotated by 80° with respect to each other, and the hydroxyl oxygen atoms are 2.66 Å apart. The molecular parameters help to delineate limits of stereochemical variation in these molecules with retention of anticonvulsant activity.

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