Synthesis and Stabilization of Crystal Hydrate Modification SrSO4⋅0.5H2O

The reactivity of the organosamarium(II) indenyl complex (C9H7)2Sm(THF)x, 1, has been compared with that of (C5Me5)2Sm(THF)2, 2, and (C5Me5)2Sm, 3, by examination of characteristic organosamarium(II) reactions which form trivalent oxide, iodide, cyclo‐octatetraenyl and azobenzene complexes. Complex 1 reacts with excess N2O to form [(C9H7)2Sm(THF)]2(μ‐O), 4, and (C9H7)3Sm(THF), 5, as the major products. Two equivalents of 1 react with one equivalent of 1,2‐di‐iodoethane in THF to give (C9H7)SmI2(THF)2, 6, as well as 5. Complex 1 reacts with 1,3,5,7‐cyclo‐octatetraene in a 2:1 ratio in THF to form 5 and (C9H7)Sm(C8H8)(THF)x, 7, which has been fully characterized as the 2,2′‐bipyridine adduct (C9H7)Sm(C8H8)(C10H8N2), 7a. The reaction of 1 with azobenzene in a 2:1 ratio forms [(C9H7)Sm(N2Ph2)(THF)]x, 8, and 5. Complexes 4–6 and 7a have been definitively identified by X‐ray crystallography.Complex 4 crystallizes from THF in space group P1― [C; No. 2] with unit cell parameters at 163 K of a = 8.072(2) Å, b = 9.502(2) Å, c = 12.250(3) Å, α = 101.42(2)°, β = 90.71(2)°, γ = 102.50(2)°, V = 897.7(4) Å3 and Z = 1 for Dcalcd = 1.704 Mgm−3. Least‐squares refinement of the model based on 3924 reflections (|F0|)>3.0 σ (|F0|)) converged to a final RF=2.4%. The geometry around each Sm atom is a distorted tetrahedron and the Sm–O–Sm angle is 180°.Complex 5 crystallizes from THF/hexanes at −35°C in space group P63 [C; No. 173] with unit cell parameters at 163 K of a = 11.7370(14) Å, c = 10.1994(12) Å, V = 1216.8(3) Å3 and Z = 2 for Dcalcd = 1.550 Mg m−3. Least‐squares refinement of the model based on 976 reflections (|F0|> 3.0σ (|F0|) converged to a final RF = 2.3%. The three ring centroids and the THF oxygen atom define a distorted tetrahedron around samarium with a (ring centroid)–Sm–(ring centroid) angle of 116.0°.Complex 6 crystallizes from THF/hexanes as the trisolvate (C9H7)SmI2(THF)3, 6a, in space group P21/n [C; No. 14] with unit cell parameters at 163 K of a = 8.3969(12) Å, b = 17.165(5) Å, c = 33.592(7) Å, β = 96.468(15)°, V = 4811(2) Å3 and Z = 8 for Dcalcd = 2.031 Mg m−3. Least‐squares refinement of the model based on 5664 reflections (|F0|> 2.0 σ (|F0|)) converged to a final RF = 3.3%. The six ligands around Sm in 6a describe a distorted octahedron. The iodide ligands are trans to each other with a 153.8(1)° I–Sm–I angle.Adduct 7a crystallizes from hot THF/toluene in space group P1 [C; No. 2] with a unit cell parameters at 163 K of a = 7.886(7) Å, b = 16.72(2) Å, c = 17.48(2) Å, α = 62.96(7)°, β = 85.17(7)°, γ = 85.23(9)°, V = 2042(3) Å3 and Z = 4. The cyclooctateraenyl and indenyl ligands generate a bent metallocene structure for 7a which contains a chelating bipyridyl group in the plane bisecting the two rings.

The rare minerals, inesite, Ca2Mn2+7Si10O28(OH)2·5H2O, hubeite, Ca2Mn2+Fe3+Si4O12(OH)·2H2O, and ruizite, Ca2Mn3+Si4O11(OH)4·2H2O, were determined, for the first time, by optical and XRD analyses, at Cavnic (Baia Mare Neogene metallogenetic district, Eastern Carpathians, Romania) in a gold-bearing, base metal deposit. Inesite was refined as triclinic, in space group P1 (2), and has the following unit-cell parameters (refined from X-ray powder diffraction data): a = 8.927(7) Å, b = 9.245(8) Å, c = 11.954(9) Å; α = 91.80(2)°, β = 132.60(1)°, γ = 94.37(3)°, V = 719.45(12)Å3. Hubeite was also refined as triclinic, in space group P1, and has as unit-cell parameters: a = 9.960(7) Å, b = 13.870(9) Å, c = 6.562(4) Å, V = 601.19(17) Å3; α = 133.19(5)°, β =101.50(3)°, γ = 66.27(4)°. Ruizite was refined on a monoclinic cell, space group A2 (5) and has the following unit-cell parameters: a = 11.974(9)Å, b = 6.175(5)Å, c = 9.052(7)Å, V = 669.12 (9)Å3; β = 91.34(3)°. Apophyllite, KCa4Si8O20(F,OH)·8H2O, is tetragonal, space group P4/mnc (128), and has a = 8.960(3) Å, c = 15.767(7) Å and V = 1265.80(11) Å3. The terms identified represent a solid solutions series between the two end-members, fluorapophyllite and hydroxyapophyllite. Manganoan ilvaite, CaFe2+Fe3+(Fe2+, Mn)(Si2O7)(O)(OH), crystallizes in the space group Pnam (62), and has as unit-cell parameters: a = 13.008(7) Å; b = 8.865(5) Å; c = 5.845(3) Å, V = 674.02(9) Å3. The textural relations of inesite /hubeite/ruizite /apophyllite/manganoan ilvaite assemblage show that the oldest mineral is manganoan ilvaite, as inesite and hubeite overgrow and engulf this mineral. Hubeite is indicative for mildly oxidizing crystallization, conditions. Both hubeite and ruizite are Ca-Mn hydrated silicates. However, all Mn is divalent in hubeite and trivalent in ruizite. In addition, ruizite is Fe-free, whereas hubeite contains significant Fe3+. Ruizite Ca2Mn3+Si4O11(OH)4.2H2O was formed under higher oxidizing conditions as compared with hubeite. Sudoite and specularite also occurs in this oxidized assemblage. Sudoite, Mg2(Al.Fe3+)3Si3O10(OH)8, is monoclinic and has as space group C2m (12) and as unit-cell parameters a = 5.237(2) Å, b = 9.070(5) Å, c = 14.285(8), β = 97.00, V = 673.47(14) Å3. The carbonate closely associated to this assemblage is a Mn- and Ca-bearing siderite, which crystallizes in space group R-3c (167), having as unit-cell parameters: a = 4.694(1) Å; c = 15.386(5) Å, and V = 293.53(13) Å3. The secondary minerals occurring in this assemblage as determined by X-ray powder diffraction are: gold, sphalerite, pyrite, and galena. The origin of vein assemblage inesite /hubeite /ruizite /apophyllite is hydrothermal (epithermal); there exist indications of a genesis at low temperature, around 200°C. The assemblage indicated before is grown on manganoan ilvaite, which is the oldest mineral in this association. There are no signs of the genesis of manganoan ilvaite /inesite /hubeite /ruizite assemblage at the expense of higher T anhydrous manganese minerals such as rhodonite or johannsenite.

The ccd toxin-antitoxin module from the Escherichia coli F plasmid has a homologue on the Vibrio fischeri integron. The homologue of the toxin (CcdB(Vfi)) was crystallized in two different crystal forms. The first form belongs to space group I23 or I2(1)3, with unit-cell parameter a = 84.5 A, and diffracts to 1.5 A resolution. The second crystal form belongs to space group C2, with unit-cell parameters a = 58.5, b = 43.6, c = 37.5 A, beta = 110.0 degrees, and diffracts to 1.7 A resolution. The complex of CcdB(Vfi) with the GyrA14(Vfi) fragment of V. fischeri gyrase crystallizes in space group P2(1)2(1)2(1), with unit-cell parameters a = 53.5, b = 94.6, c = 58.1 A, and diffracts to 2.2 A resolution. The corresponding mixed complex with E. coli GyrA14(Ec) crystallizes in space group C2, with unit-cell parameters a = 130.1, b = 90.8, c = 58.1 A, beta = 102.6 degrees, and diffracts to 1.95 A. Finally, a complex between CcdB(Vfi) and part of the F-plasmid antitoxin CcdA(F) crystallizes in space group P2(1)2(1)2(1), with unit-cell parameters a = 46.9, b = 62.6, c = 82.0 A, and diffracts to 1.9 A resolution.

La(UO2)V2O7][(UO2)(VO4)] the first lanthanum uranyl-vanadate with structure built from two types of sheets based upon the uranophane anion-topology

The syntheses, structural characterization, and magnetic behavior of five new 2D manganese(II) complexes with empirical formulas [Mn(N(3))(2)(2,6-DiMepyz)(H(2)O)](n)() (1), [Mn(N(3))(2)(Etpyz)(H(2)O)](n)() (2), [Mn(N(3))(2)(H(2)O)(2)](n)()(2,3-DiMepyz)(n)() (3), [Mn(N(3))(2)(Clpyz)(2)](n)() (4), and [Mn(N(3))(2)(Ipyz)(2)](n)() (5) (pyz = pyrazine (1,4-diazine)) are reported. 1 crystallizes in the monoclinic system, space group P2(1)/c, with unit cell parameters a = 7.513(4) A, b = 17.438(7) A, c = 8.404(4) A, beta = 94.53(4) degrees , and Z = 4. 2 crystallizes in the triclinic system, space group P, with unit cell parameters a = 7.386(2) A, b = 8.434(2) A, c = 9.442(3) A, alpha = 71.82(2) degrees , beta = 72.08(2) degrees , gamma = 88.54(2) degrees , and Z = 2. 3 crystallizes in the monoclinic system, space group C2/c, with unit cell parameters a = 20.438(7) A, b = 7.711(2) A, c = 7.457(2) A, beta = 93.76(3) degrees , and Z = 4. 4 crystallizes in the orthorhombic system, space group Pbca, with unit cell parameters a = 8.600(2) A, b = 13.440(4) A, c = 24.083(7) A, and Z = 8. 5 crystallizes in the orthorhombic system, space group Pbca, with unit cell parameters a = 8.521(2) A, b = 13.787(3) A, c = 26.237(5) A, and Z = 8. The compounds 1-5 have only azido bridging ligands. In 1-3 each manganese atom is linked to the four nearest neighbors by only end-to-end azido bridges, forming square layers. 4 and 5 show alternating end-to-end and end-on azido bridges between manganese atoms. The magnetic properties of 1-5 are reported. At high temperatures the plots of chi(M) or chi(M)T vs T for the 1-3 compounds can be fitted as homogeneous 2D systems with J = -4.9, -4.4, and -3.9 cm(-)(1) for 1-3, respectively. For 1, 3, and 5 magnetic ordering and spontaneous magnetizations is achieved below T(c) = 35, 29, and 22 K, respectively, whereas 2 and 4 do not show spontaneous magnetization up to 2 K.

Crystal structures and structural relationships of KFe2(SeO2OH)(SeO3)3 and SrCo2(SeO2OH)2(SeO3)2

Crystals of lutetium disilicate (Lu2Si2O7) have been synthesized at 4 GPa and 1200 °C, using a piston-cylinder type high-pressure apparatus. Systematic single-crystal X-ray structure analysis shows that Lu2Si2O7, type X is enantiomorphic in space groups P41212 (structure 1) and P43212 (structure 2). Unit cell parameters are a = 6.5620(2), c = 11.9535(4) A (1, space group P41212) and a = 6.5621(9), c = 11.954(2) A (2, space group P43212), respectively. The crystal structures of the two enantiomers are based on helical chains of Lu cations linked by [Si2O7]6− groups, which are parallel to each other and possess the same chirality, being right-handed for structure 1 and left-handed for structure 2. More interesting is that we have directly observed the helical chain under high-resolution transmission electron microscopy (HRTEM).

The N-terminal type II cohesin from the cellulosomal ScaB subunit of Acetivibrio cellulolyticus was crystallized in two different crystal systems: orthorhombic (space group P2(1)2(1)2(1)), with unit-cell parameters a = 37.455, b = 55.780, c = 87.912 A, and trigonal (space group P3(1)21), with unit-cell parameters a = 55.088, b = 55.088, c = 112.553 A. The two crystals diffracted to 1.2 and 1.9 A, respectively. A selenomethionine derivative was also crystallized and exhibited trigonal symmetry (space group P3(1)21), with unit-cell parameters a = 55.281, b = 55.281, c = 112.449 A and a diffraction limit of 1.97 A. Initial phasing of the trigonal crystals was successfully performed by the SIRAS method using Cu Kalpha radiation with the selenomethionine derivative as a heavy-atom derivative. The structure of the orthorhombic crystal form was solved by molecular replacement using the coordinates of the trigonal form.

S100A12 is a member of the S100 family of EF-hand calcium-modulated proteins. Together with S100A8 and S100A9, it belongs to the calgranulin subfamily, i.e. it is mainly expressed in granulocytes, although there is an increasing body of evidence of expression in keratinocytes and psoriatic lesions. As well as being linked to inflammation, allergy and neuritogenesis, S100A12 is involved in host-parasite response, as are the other two calgranulins. Recent data suggest that the function of the S100-family proteins is modulated not only by calcium, but also by other metals such as zinc and copper. Previously, the structure of human S100A12 in low-calcium and high-calcium structural forms, crystallized in space groups R3 and P2(1), respectively, has been reported. Here, the structure of S100A12 in complex with copper (space group P2(1)2(1)2; unit-cell parameters a = 70.6, b = 119.0, c = 90.2 A) refined at 2.19 A resolution is reported. Comparison of anomalous difference electron-density maps calculated with data collected with radiation of wavelengths 1.37 and 1.65 A shows that each monomer binds a single copper ion. The copper binds at an equivalent site to that at which another S100 protein, S100A7, binds zinc. The results suggest that copper binding may be essential for the functional role of S100A12 and probably the other calgranulins in the early immune response.

The title compound, 2-amino-4,6-dimethylpyrimidine 2-hydroxybenzoate was studied by X-ray diffraction methods. This compound crystallized in a monoclinic system; space group P2(1)/n with the unit cell parameters a = 7.5380(14) A, b = 20.246(4) A, c = 9.2029(17) A, β = 108.594(3), V = 1331.2(4), Z = 4. The hydroxybenzoic acid group has been protonated by the aminopyrimidine moiety. The neighbouring two pyrimidine are bridged by N3–H3A···N2 hydrogen bonds, and the constituting dimers are linked together to form a discrete unit, these units, in turn, are linked together by C–H···O interactions. The protonated N1 atom is attached to the carboxyl group (O2) of the neighbouring phenyl by a hydrogen bond, together with the N3–H3B···O3 hydrogen bond to form a eight-membered ring with graph-set notation R 2 1 (8). The C5 and O1 through hydrogen bond forms a supramolecular chain along the b-axis, which is further strengthened by O1–H1···O3 hydrogen bond, bridging the hydroxide radical and carboxyl via hydrogen bonded rings, R 1 1 (6). A novel compound, 2-amino-4,6-dimethylpyrimidium 2-hydroxybenzoate was obtained and its structure was studied by single crystal X-ray diffraction. This compound crystallized in a monoclinic system; space group P2(1)/n with the unit cell parameters a = 7.5380(14) A, b = 20.246(4) A, c = 9.2029(17) A, β = 108.594(3), V = 1331.2(4), Z = 4.

Synthesis and structure of chloro(ligand)bis(diphenylglyoximato)cobalt(III) complexes

Crystal structures of NTDIOO derivatives

X-Ray diffraction studies and energy-minimization calculations were carried out on two dipeptides, N-tosyl-L-Ser-Gly-OMe monohydrate (C13H18N2O6S.H2O, compound A) and N-tosyl-L-Thr-Gly-OMe (C14H20N2O6, compound B). Compound A crystallized in the monoclinic system, space group P2(1) with unit cell parameters a = 4.915(1), b = 15.625(4), c = 11.003(1) A, beta = 91.28(1) degrees, V = 844.8 A3. M(r) = 348.4, d = 1.37(2) g cm-3, Z = 2, lambda(Cu K alpha) = 1.5418 A, mu = 1.99 mm-1, T = 293 K. R = 0.032 for 1451 unique reflections with I > 2 sigma(I). Compound B crystallized in the orthorhombic system, space group P2(1)2(1)2(1), with unit cell parameters a = 5.050(2), b = 16.483(3), c = 20.769(5) A, V = 1729.3 A3, Z = 4. M(r) = 344.4, d = 1.32(2) g cm-3, mu(Cu K alpha) = 1.90 mm-1. R = 0.040 for 1060 unique reflections with I > 2 sigma(I). The major difference in the backbone conformation of the two compounds is in their glycine residues, with the glycine residue in compound A adopting an extended conformation with phi = -132.6(3) degrees and psi = 175.3(3) degrees and that in compound B having a folded conformation with phi = -56.3(6) degrees and psi = -42.6(7) degrees. In compound A the oxygen atom of the Ser side-chain and the carbonyl oxygen atom of glycine are bridged by the water of crystallization through O--H ... O hydrogen bonds, resulting in the relatively rare trans conformation [chi = -175.7(2) degrees] for this side-chain.(ABSTRACT TRUNCATED AT 250 WORDS)

Baloxavir marboxil (BXM) is a new blockbuster FDA-approved anti-influenza virus agent. However, its poor solubility has limited its oral bioavailability. In this study, BXM was crystallized from several organic solvents, obtaining three polymorphs, and their dissolution behaviors were studied. Detailed crystallographic examination revealed that Form I is monoclinic, space group P21, with unit cell parameters a = 7.1159 (3) Å, b = 20.1967 (8) Å, c = 9.4878 (4) Å, β = 109.033 (1)°, V = 1289.02 (9) Å3, and Z = 2, and Form II is monoclinic, space group P21, with unit cell parameters a = 7.1002 (14) Å, b = 39.310 (7) Å, c = 9.7808 (18) Å, β = 110.966 (5)°, V = 2549.2 (8) Å3, and Z = 4. Form I has a rectangular three-dimensional energy frameworks net, while Form II has a two-dimensional net. On the other hand, Form II has a much larger percentage of its surface area of exposed hydrogen bond acceptors than Form I. These crystallographic features offered increased solubility and dissolution rate to Form II. The results of stability and solubility experiments suggest that Form II may be preferred in the solid form used for the industrial preparation of BXM medicinal products.

The direct-method program MULTAN88 has been applied to solve a known protein, pseudoazurin, space group P6(5), unit-cell parameters a = b = 50.0 (1), c = 98.5 (3) A, with 917 protein atoms, a Cu atom and 93 solvent water molecules in the asymmetric unit (>6,000 non-H atoms in the unit cell) and data at 1.55 A resolution. One of several trials with sets of initially random phases yielded phase estimates for 1,000 reflections with a mean phase error of 68.3 degrees that was recognized as the best available solution by the figure of merit being used. Phase extension to 2,000 largest Es showed a distorted tetrahedral geometry around the Cu site. Density modification was applied to improve the phases and the quality of the maps, starting with phases calculated from the atomic positions indicated by the first map.