Synthesis and Spectroscopic Characterization of Mixed Diamidophosphoric Acid Esters: X-Ray Crystal Structure of [(CH3)2N]-[p-H3C-C6H4-O]P(O)X (X = NHC(CH3)3 and p-H3C-C6H4-NH)

2009 ◽  
Vol 64 (5) ◽  
pp. 565-569 ◽  
Author(s):  
Saied Ghadimi ◽  
Mehrdad Pourayoubi ◽  
Ali Asghar Ebrahimi Valmoozi

Mixed diamidophosphoric acid esters [(CH3)2N][p-H3C-C6H4-O]P(O)X, where X = NH(CH3) (1), NHCH(CH3)2 (2), NHC(CH3)3 (3) and p-H3C-C6H4-NH (4) were synthesized and characterized by 31P, 31P{1H}, 13C, 1H NMR, and IR spectroscopy and mass spectrometry, and single crystal X-ray diffraction analysis for the compounds 3 and 4. Compound 3 crystallizes in the monoclinic, space group P21/c with unit cell parameters a = 9.006(3), b = 16.286(5), c = 10.319(3) A° , β = 99.633(6)◦, V = 1492.2(8) °A3, Z = 4. The final R value is 0.0622 for 2074 reflections [I ≥ 2σ (I)]. Compound 4 crystallizes in the orthorhombic, space group Pna21 with unit cell parameters a = 7.0459(14), b = 20.934(4), c = 10.436(2) ° A, V = 1539.3(5) °A3, Z = 4. The final R value is 0.0530 for 3025 reflections [I ≥ 2σ (I)].

1999 ◽  
Vol 55 (11) ◽  
pp. 1928-1929 ◽  
Author(s):  
Junichi Komoto ◽  
Yafei Huang ◽  
Yongbo Hu ◽  
Yoshimi Takata ◽  
Kiyoshi Konishi ◽  
...  

Guanidinoacetate methyltransferase is the enzyme which catalyzes the last step of creatine biosynthesis. The enzyme is found ubiquitously and in abundance in the livers of all vertebrates. Recombinant rat-liver guanidinoacetate methyltransferase has been crystallized with guanidinoacetate and S-adenosylhomocysteine. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 54.8, b = 162.5, c = 56.1 Å, β = 96.8 (1)° at 93 K, and typically diffract beyond 2.8 Å.


Author(s):  
Analio Dugarte-Dugarte ◽  
Nahum Ramírez Pineda ◽  
Luis Nieves ◽  
José Antonio Henao ◽  
Graciela Díaz de Delgado ◽  
...  

Almost 50 years after the initial report, the crystal structure of Cu2GeSe3, a I2-IV-VI3 semiconductor, has been revised using modern single-crystal X-ray diffraction data. The structure of this material can be properly described in the monoclinic space group Cc (No. 9) with unit-cell parameters a = 6.7703 (4) Å, b = 11.8624 (5) Å, c = 6.7705 (4) Å, β = 108.512 (6)°, V = 515.62 (5) Å3, Z = 4, rather than in the orthorhombic space group Imm2 (No. 44) with unit-cell parameters a = 11.860 (3), b = 3.960 (1), c = 5.485 (2) Å, V = 257.61 Å3, Z = 2, as originally proposed [Parthé & Garín (1971). Monatsh. Chem. 102, 1197–1208]. Contrary to what was observed in the orthorhombic structure, the distortions of the tetrahedra in the monoclinic structure are consistent with the distortions expected from considerations derived from the bond valence model. A brief revision of the structures reported for the I2-IV-VI3 family of semiconducting compounds (I: Cu, Ag; IV: Si, Ge, Sn; and VI: S, Se, Te) is also presented.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Akhmatkhodja N. Yunuskhodjayev ◽  
Shokhista F. Iskandarova ◽  
Vahobjon Kh. Sabirov

Abstract The crystal structure of a copper(II) complex of protonated sildenafil, CuCl3C22H31N6O4S⋅2H2O was studied by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 15.4292(2), b = 9.06735(12), c = 21.1752(2) Å, V = 2945.48(7) Å3, Z = 4. The Cu atom is coordinated by the sildenafil ligand via the N2 atom of the pyrazolopyrimidine ring and by three chloride anions. Sildenafil is protonated at the methylated N6 atom of the piperazine ring and it is cation ligand with a 1+ charge.


2014 ◽  
Vol 70 (10) ◽  
pp. 1389-1393 ◽  
Author(s):  
Mulu Y. Lubula ◽  
Amanda Poplawaski ◽  
Karen C. Glass

The bromodomain-PHD finger protein 1 (BRPF1) is an essential subunit of the monocytic leukemia zinc (MOZ) histone acetyltransferase (HAT) complex and is required for complex formation and enzymatic activation. BRPF1 contains a structurally conserved bromodomain, which recognizes specific acetyllysine residues on histone proteins. The MOZ HAT plays a direct role in hematopoiesis, and deregulation of its activity is linked to the development of acute myeloid leukemia. However, the molecular mechanism of histone-ligand recognition by the BRPF1 bromodomain is currently unknown. The 117-amino-acid BRPF1 bromodomain was overexpressed inEscherichia coliand purified to homogeneity. Crystallization experiments of the BRPF1 bromodomain in complex with its H4K12ac and H2AK5ac histone ligands yielded crystals that were suitable for high-resolution X-ray diffraction analysis. The BRPF1 bromodomain–H4K12ac crystals belonged to the tetragonal space groupP43212, with unit-cell parametersa= 75.1,b= 75.1,c= 86.3 Å, and diffracted to a resolution of 1.94 Å. The BRPF1 bromodomain–H2AK5ac crystals grew in the monoclinic space groupP21, with unit-cell parametersa= 60.9,b= 55.6,c= 82.1 Å, β = 93.6°, and diffracted to a resolution of 1.80 Å. Complete data sets were collected from both crystal forms using synchrotron radiation on beamline X29 at Brookhaven National Laboratory (BNL).


1994 ◽  
Vol 9 (2) ◽  
pp. 98-104
Author(s):  
Jaakko Leppä-aho ◽  
Jussi Valkonen

X-ray powder diffraction data are reported for a series of isomorphous compounds of [Ln2(CrO4)3(H2O)5]·2H2O, where Ln=La, Pr, Nd, Sm, or Eu. The compounds crystallize in monoclinic space group P21/c (No: 14) with Z=4. Refined unit cell parameters and indexed powder diffraction patterns are given.


1987 ◽  
Vol 2 (1) ◽  
pp. 2-4 ◽  
Author(s):  
John L. Jambor ◽  
Andrew C. Roberts ◽  
Joel D. Grice

AbstractTabular untwinned crystals of colorless transparent armstrongite from the Strange Lake Alkalic Complex, on the Quebec – Labrador boundary, Canada are monoclinic, space group choices I2/m, I2, Im (diffraction aspect I*/*), with refined unit-cell parameters a = 13.599 (9), b = 14.114(9), c = 7.833 (4) Å, β = 103.41 (5)°, V = 1462.4 (±3.0) Å3. a:b:c = 0.9635:1:0.5550, Z = 4 and D(x) = 2.696 g/cm3. A fully indexed X-ray powder pattern is presented. Averaged electron-microprobe analyses suggest a theoretical formula of CaZrSi6O15 · 3 H2O. The Strange Lake armstrongite is biaxial negative, α = 1.567 (1), β = 1.576 (1), γ = 1.577 (1), 2V (meas.) = 39 (1)°, 2V (calc.) = 37°, Z∥b, X Λc = +4°, with no absorption and weak dispersion r < v.


1999 ◽  
Vol 14 (1) ◽  
pp. 49-52
Author(s):  
Hongxiang Wu ◽  
Lidun Ma

X-ray powder data are given for cobalt tris-ethylenediamine bromide trihydrate, [Co(en)3]Br3·3H2O, and cobalt tris-ethylenediamine iodide hemihydrate, [Co(en)3]I3·0.5H2O. Refined unit-cell parameters for [Co(en)3]Br3·3H2O are a=11.6949(4) Å and c=16.0640(12) Å in trigonal space group P3¯c1(165) or P3c1(158); volume =1902.72 Å3; figures of merit: M20=29, F30=55 (0.0138, 40). Refined unit-cell parameters for [Co(en)3]I3·0.5H2O are a=23.3580(14) Å, b=13.4739(4) Å, and c=11.5421(5) Å in orthorhombic space group Pca21(29) or Pcam(57); volume =3632.57 Å3; figures of merit: M20=37, F30=81 (0.0058, 64).


Author(s):  
Xavier Kubiak ◽  
Benjamin Pluvinage ◽  
Inès Li de la Sierra-Gallay ◽  
Patrick Weber ◽  
Ahmed Haouz ◽  
...  

ArylamineN-acetyltransferases (NATs) are xenobiotic metabolizing enzymes (XMEs) that catalyze the acetylation of arylamines. All functional NATs described to date possess a strictly conserved Cys-His-Asp catalytic triad. Here, the purification, crystallization and preliminary X-ray characterization ofBacillus cereusarylamineN-acetyltransferase 3 [(BACCR)NAT3], a putative NAT isoenzyme that possesses a unique catalytic triad containing a glutamate residue, is reported. The crystal diffracted to 2.42 Å resolution and belonged to the monoclinic space groupC121, with unit-cell parametersa= 90.44,b= 44.52,c = 132.98 Å, β = 103.8°.


1999 ◽  
Vol 55 (4) ◽  
pp. 904-906 ◽  
Author(s):  
Hanspeter Lauble ◽  
Klaas Decanniere ◽  
Harald Wajant ◽  
Siegfried Förster ◽  
Franz Effenberger

Hydroxynitrile lyase from M. esculenta (cassava) was crystallized in two different crystal forms by the hanging-drop vapour-diffusion method. Crystals of form I were obtained from a mixture of polyethylene glycol 8000 and 2-methyl-2,4-pentanediol, and belong to the tetragonal space group P41212 or its enantiomorph P43212, with unit-cell parameters a  =  b  =  105.9, c  =  188.9 Å and with two molecules in the asymmetric unit. These crystals diffract to 2.9 Å with conventional X-ray sources and beyond 2.1 Å resolution with synchrotron radiation. The crystals are relatively sensitive to radiation damage and conditions for flash-cooling the crystals have been established. A complete native data set has been collected up to 2.2 Å resolution. Crystal form II has been obtained at pH 5.6 using lithium sulfate as a precipitant. The crystals apparently belong to the orthorhombic space group P21212, with unit-cell parameters a = 117.52, b = 127.09 and c = 78.08 Å, have two molecules in the asymmetric unit and diffract to beyond 2.0 Å resolution. A complete native data set has been collected to 2.2 Å resolution.


2019 ◽  
Vol 10 (3) ◽  
pp. 201-208
Author(s):  
Pokpa Haba ◽  
Adama Sy ◽  
Farba Bouyagui Tamboura ◽  
Mamour Sarr ◽  
Ibrahima Elhadji Thiam ◽  
...  

Reactions of the Schiff base N,N-dimethyl-N'-((5-methyl-1H-imidazol-4-yl)methylene) ethane-1,2-diamine (HL), synthesised in situ, with chloride or thiocyanate copper (II) salt; afforded two new mononuclear complexes, [Cu(HL)Cl2]·H2O (1) and [Cu(HL)(SCN)2] (2). These compounds have been studied and characterized by elemental analysis, IR and UV-Vis spectroscopies, electrochemistry, molar conductivity and room temperature magnetic measurements. Single crystal X-ray structure determination of the complexes revealed the presence of neutral moieties in the asymmetric unit. The mononuclear (1) crystallises in the monoclinic space group P21/c with the following unit cell parameters a = 7.4355(3) Å, b = 7.2952(3) Å, c = 26.2729(11) Å, β = 93.461(4)°, V = 1422.52(10) Å3, Z = 4, R1 = 0.033 and wR2 = 0.082 and the mononuclear complex (2) crystallises in the monoclinic space group C2/c with the following unit cell parameters a = 26.2578(7) Å, b = 7.4334(2) Å, c = 16.6237(5) Å, β = 99.089(3)°, V = 3203.95(16) Å3, Z = 8, R1 = 0.037 and wR2 = 0.104. In both complexes the ligand acts in tridentate fashion and the coordination environment of the copper atom can be described as distorted square pyramidal. The crystal lattice of the complex 1 is stabilized by electrostatic forces of attraction and O–H···Cl, C–H···O, N–H···Cl, and C–H···Cl, hydrogen bonding interactions while the crystal lattice of the complex 2 is stabilized by N–H···S and C–H···N.


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