Synthesis and structure of (±)-4-O-methanesulfonyl-myo-inositol 1,3,5-orthoformate

Racemic 4-O-methanesulfonyl-myo-inositol 1,3,5-orthoformate was prepared by methanolysis of racemic 2,4-di-O-benzoyl-4-O-methanesulfonyl-myo-inositol 1,3,5-orthoformate, in the presence of triethylamine. The diol crystallizes in space group P2₁2₁2₁ with cell dimensions a = 6.094(1), b = 6.502(2), c = 25.947(3) Å, V = 1028.1(4) Å, Z = 4. The molecular crystals show both intra- and intermolecular O—H···O short contacts. The methine and the methyl hydrogens are involved in several C—H···O interactions.     

Identification of a new family of diphosphate compounds, AI2BII3(P2O7)2: Structures of Ag2Co3(P2O7)2, Ag2Mn3(P2O7)2, and Na2Cd3(P2O7)2

Syntheses and single-crystal X-ray structural results are reported for three new mixed diphosphates of the family A^I ₂B^II ₃(P₂O₇)₂; Ag₂Co₃(P₂O₇)₂ (I), Ag₂Mn₃(P₂O₇)₂ (II), and Na₂Cd₃(P₂O₇)₂ (III). All crystallize in the triclinic system, space group P1 bar: (I) a = 5.351(4), b = 6.375(4), c = 16.532(4) Å, = 80.83(6) = 81.45(4), = 72.87(5)°, V = 528.9(6) ų, Z = 2, D _calc = 4.649 mg/m³, R/Rw = 0.0428/0.0548 for 3949 obs. reflns; (II) a = 5.432(7), b = 6.619(6), c = 16.51(3) Å, = 80.78(8) = 82.43(9), = 72.82(7)°, V = 557.7(13) ų, Z = 2, D _calc = 4.338 mg/m³, R/Rw = 0.0679/0.1303 for 2100 obs. reflns and (III) a = 5.67(3), b = 7.08(4), c = 7.90(4) Å, = 77.0(2), = 82.5(2), = 67.8(2)°, V = 286(3) ų, Z = 2, D _calc = 4.249 mg/m³, R/Rw = 0.0307/0.0342 for 1945 obs. reflns. (I) and (II) are isostructural but (III) is of a different type. All three structures are characterized by layers of P₂O₇ groups alternating with layers of mixed metal atoms. Differences are seen in the conglomerate bonding patterns of B atoms and in the irregular geometry of Ag in (I) and (II) compared to the octahedral bonding seen for Na in (III). The differences in structure may be understood in terms of the ratios of the ionic radii of A and B atoms.     

X-ray structure of 2,6-dimethoxy-7-methylpurine

The title compound (C₈H₁₀N₄O₂) is monoclinic, with a = 7.740(2), b = 17.044(7), c = 6.992(3) Å, = 100.60(1)°, and space group P2₁/c. Two O-methyl groups are coplanar with the pyrimidine ring. Whereas, the O(6)-methyl group is directed away from the imidazole ring toward the N(1) atom, the O(2)-methyl is pointed away from the N(1) atom toward the N(3) atom. Two intermolecular hydrogen bonds H(8)···N(1) and H(711)···O(2) of 2.48(2) and 2.58(3) Å make a linear arrangement of the molecules. The conformation of the O-methyl groups explains some results of thermal rearrangement of 2,6-dialkoxy-7-methylpurines and differences in alkylations of 2,4-dialkoxypyrimidines and 2,6-dialkoxy-7-methylpurines.     

Preparation,spectral studies and X-ray crystal structure of 1,3,5-triphenyl-1,5-pentanedione,C23H20O2

1,3,5-triphenyl-1,5-pentanedione, C₂₃H₂₀O₂, has been prepared and characterized by spectroscopic methods and single crystal X-ray analysis. Crystals are monoclinic, space groupP2₁/n, a=28.124(4),b=5.997(1),c=10.434(1)Å, -98.42(1)Å,Z=4. The structure has been refined to a finalR-value of 0.040 for 1625 reflections withF _o>3(F _o). The compound contains the two carbonyl groups in a mutuallycis arrangement.     

The crystal and molecular structure of bis(melamine)silver(I) perchlorate, Ag(C3H6N6)2ClO4

The crystal structure of the title compound, Ag(mela)₂ClO₄ (mela = melamine), has been investigated by X-ray diffraction techniques, the crystals are triclinic, space group P1¯, with a = 5.236(2), b = 7.5385(9) c = 19.063(3) Å, = 99.91(1), = 90.53(2), = 108.32(2)° and Z = 2. The Ag atom has a coordination geometry with two strong bonds (2.162(2) and 2.179(4) Å) to the nitrogen of the melamines and two weak bonds (2.776(4) and 2.785(4) Å) to oxygen atoms of the ClO^– ₄anions. The N—Ag—N vector is markedly nonlinear (angle at Ag 167.7(2)°).     

Synthesis and crystal structure of 2-benzoyl-4-methyl phenyl benzoate

The crystal structure of the title compound, C₂₁H₁₆O₃, has been determined. The compound crystallizes in triclinic space group PĪ with cell parameters a = 9.2240(9) Å, b = 9.8050(8) Å, c = 10.1610(11) Å, α = 94.749(6)^∘, β = 112.544(4)^∘, γ = 102.145(6)^∘ and Z = 2. The structure exhibits both intra and intermolecular interactions of the type C–H ⋅s O. The intermolecular interaction between the molecules form centrosymmetric dimers.     

Synthesis and structure of 4,7,13,16-tetraoxa-1,10-diaza-5,6-benzocyclooctadeca-11,18-dione monohydrate

4,7,13,16-tetraoxa-1,10-diaza-5,6-benzocyclooctadeca-11,18-dione, C₁₆H₂₂N₂O₆·H₂O, (3) was synthesized under thermal conditions, starting from ,-diamine (1) and ,-diester (2). The hydrate of compound (3) was investigated in the solid state by X-ray structural analysis. Crystal data: monoclinic system, space group P2₁/c,a=12.342(4) Å,b=15.978(7) Å,c=8.960(3) Å, =96.72(3)°,Z=4. The structure was solved by direct methods and refined to finalR=0.056,R _w=0.069 for 1962 observed reflections. The structure exhibits internal hydrogen bonds between the etheral O(16) atom and the neighboring amide group. The water molecule connects diamide molecules by one strong hydrogen bond with carbonyl oxygen, and four weak hydrogen bonds with the amide groups and etheral oxygen atoms.     

O-benzyl-N-(2-furoyl)thiocarbamate

The O-benzyl-N-(2-furoyl)thiocarbamate (1) was obtained by direct reaction between furoyl isothiocyanate and benzyl alcohol. The X-ray diffraction analysis of 1 showed an orthorhombic system, with a = 7.811(4) Å, b = 9.685(4) Å, c = 33.562(15) Å, and space group P2₁2₁2₁. This compound showed two different arrays of structure, corresponding to two conformers in the same crystal unit. In one conformer the carbonyl and thiocarbonyl groups are in a syn arrangement while in the other the groups are anti. Both structures present a non-restricted conformation and show NH—OC hydrogen bonding between them.     

Crystal structure of two brom containing aza-tetracyclic fused-ring N-heterocycles including isoxazolidine ring

Crystal structure of two brom containing aza-tetracyclic fused N-heterocycles including isoxazolidine ring compounds have been determined in single-crystal X-ray diffraction studies. The compound, C₁₄H₁₉BrN₂O₃, (1), and C₁₂H₁₅BrN₂O₃, (2), were obtained from a stereospecific[3+2] 1,3-cycloaddition of oxime based tandem nitrone generation reactions. The envelope conformation of the isoxazolidine rings are different, leading the substituents to be pseudoaxial in (1) and pseudoequatorial in (2). The stereochemistry of these fused compounds are exo- and endo-stereoisomer geometry contributed by exo and endo transition state of nitrone 1,3-dipolar cycloaddition reactions. The title compound (1) crystallizes in the monoclinic space group P2 ₁/n with a = 12.6221(5)Å, b = 7.5917(4) Å, c = 16.2350(9) Å, = 112.254(5)°, V = 1439.81(12) ų, and D _calc = 1.583 Mg/m³ for Z = 4 and compound (2) crystallizes in the monoclinic space group P2 ₁/c with a = 11.6906(9) Å, b = 6.4255(7) Å, c = 17.2070(10) Å, = 109.264(5)°, V = 1220.2(2) ų, and D _calc = 1.716 Mg/m³ for Z = 4. The antibacterial activity of both compounds were investigated for three Gram (+) and two Gram (–) bacteria by employing broth microdilution method and subsequently inhibitory activity against yeast-like fungi was also determined.     

Synthesis and crystal structure of trans-bis(O, O′-diisopropylthiophosphoryl-1H-imidazole-N3) bis(O,O′-diisopropyldithiophosphato) nickel(II) complex: Ni[N3-ImSP(OiPr)2]2[S2P(OiPr)2]2 (Im = imidazole; iPr = isopropyl)

The mononuclear complex, Ni[N³-ImSP(OiPr)₂]₂[S₂P(OiPr)₂]₂ (Im = imidazole; iPr = isopropyl), was unexpectedly obtained in a reaction of bis(O,O-diisopropyl-dithiophosphato) nickel(II) complex with imidazole ligand, and its structure was determined by X-ray crystallography. It crystallizes in the triclinic system, space group P , with lattice parameters a = 12.437(3) Å, b = 13.181(3) Å, c = 8.4580(17) Å, = 93.16(3)°, = 101.93(3)°, = 65.26(3)°, and Z = 1. The Ni atom has almost perfect octahedral coordination geometry and is coordinated by two N atoms of imidazole from two O,O-diisopropylthiophosphoryl-1H-imidazole ligands in axial positions and four S atoms from two (O,O-diisopropyldithiophosphato) anions which act as bidentate ligands forming a four-membered chelate ring in the equatorial plane. The Ni—S bond distances are 2.469(1) and 2.507(1) Å, and the Ni—N bond distances are 2.097(2) Å. The IR spectra data are in agreement with the structural data.     

Synthesis and crystal structure of charge-transfer salt (BEDT-TTF) [Pt(mnt)2]

The synthesis and crystal structure of the title organic charge-transfer salt (BEDT-TTF)[Pt(mnt)₂] (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene; mnt = cis-3,4-dimercapto-2-butenedinitrile) is described. The salt crystallizes in the P1 space group with a = 6.728(2) Å, b = 7.371(2) Å, c = 13.596(4) Å, = 97.904(5)°, = 90.114(5)°, and =108.147(5)°. The stoichiometry between BEDT-TTF and [Pt(mnt)₂] is 1:1. The bond length of the central C=C bond in a BEDT-TTF ion is 1.398 (16) Å, indicating an oxidation state of +1 in BEDT-TTF ion. The structure consists of layers of BEDT-TTF and Pt(mnt)₂ along the c axis. Within each layer, both BEDT-TTF and Pt(mnt)₂ ions form segregated stacks. The stacking is not in a face-to-face manner, but instead, is through a side-by-side arrangement along the a axis, with closest SS contacts of 3.461(3) Å between neighboring BEDT-TTF ions. The structure is consistent with the semiconducting behavior found in the solid.     

Dalspinin, an isoflavone from Dalbergia spinosa roots

The X-ray crystal structure of the plant isoflavone dalspinin from Dalbergia spinosa is determined. The compound, C₁₇H₁₂O₇, is monoclinic in P2₁/n with a = 3.970(1), b = 23.607(5), c = 14.633(3) Å, = 94.46(3)°, V = 1367.2(5) ų, D _calc = 1.595 g cm^–1 and Z = 4. The molecular structure is characterized by a short intramolecular O–H···O=C hydrogen bond, and a large tilt angle of the two rigid ring systems with respect to each other. The intermolecular interactions in the crystal are discussed.     

Separation of 4-aminobenzoic acid by cocrystallization: Crystal structure of the complex of 4-aminobenzoic acid with (2R,3R)-tartaric acid

4-Aminobenzoic acid (PABA) has been successfully separated from a mixture containing 2-aminobenzoic acid and (2R,3R)-tartaric acid. X-ray structure analysis confirms the separating result. The molecular complex formed by PABA and tartaric acid in 1:1 molar ratio crystallizes in the orthorhombic space group P2₁2₁2₁ with cell dimensions of a = 7.329(1) Å, b = 12.095(2) Å, c = 15.231(3) Å, V = 1350.1(4) ų, Z = 4. The crystal structure comprises protonated PABA, monoanion of tartaric acid, and crystalline water. The extensive H-bonding network exists in the crystal structure. H bonding between tartaric acid and both terminal groups on para position of PABA is considered as a possible reason for the successful separation.     

Crystal structures of the cis and trans isomers of a tetrathia[3.3.3.3]cyclophane

Both the cis and trans isomers of 3,11,18,26-tetrathiatricyclo[26.2.2.1^5,9.2^13,16.1^20,24] hexatriaconta-5,7,9,20,22,24-hexene have been prepared and structurally characterized. Each of these centrosymmetric tetrathia dimers includes two cyclohexane rings in chair conformations with either 1,4-cis or 1,4-trans bonding and two meta-substituted benzene rings. The cis isomer packs into the monoclinic space group P2₁/a with a = 10.485(3)Å, b = 10.3956(18)Å, c = 14.1343(10)Å, = 105.200(13)°, Z = 2 and refined to an R factor of 0.046. The trans isomer crystallizes in the monoclinic space group P2₁/c with a = 10.7217(12)Å, b = 5.6797(7)Å, c = 25.415(5)Å, = 96.001(12)°, Z = 2 and refined to an R factor of 0.043. In the cis structure each benzene ring faces a cyclohexane ring while in the trans structure the cyclohexane rings face one another.     

Redetermination of the crystal structure of [Na4(H2O)14]SnS4: a compound containing a novel chain of aquated sodium ions

[Na₄(H₂O)₁₄]SnS₄ is obtained by the reaction of Na₂S·9H₂O with SnCl₄·5H₂O in aqueous solution at 21°C. It crystallizes in the space group Cc with a = 8.621(2) Å, b = 23.543(5) Å, c = 11.358(2) Å, = 110.58(3)° and V = 2158.2 ų with Z = 2. Refinement of 3826 unique reflections from a racemically twinned crystal yielded a final value of R₁ = 0.0464 (|F| > 4) and wR₂ = 0.104 and a goodness of fit of 1.125. The structure consists of a Na⁺/H₂O network supporting the tetrahedral SnS₄ ^4– anions. Water molecules or sulfide ions octahedrally coordinate each of the four crystallographically independent Na⁺ ions. The dominant feature of the structure is the existence of zigzag chains of edgeshared Na octahedra. These chains are tied together into a three-dimensional network by bridging Na(H₂O)₆ octahedra and individual H₂O molecules.     

An X-ray diffraction study of mesoionic 1-thia-2,3,4-triazolo-5-aminidine and some of its derivatives

X-ray diffraction data are presented for the title mesoionic compound (I), its hydrochloride salt (II) and methylated derivative (III). The crystal of (I) is orthorombic, space group P2₁2₁2₁, with cell dimensions: a = 5.857(1) Å, b = 12.494(2) Å, c = 16.328(3) Å, with four molecules per unit cell. The crystal of (II) is monoclinic, space group P2₁/n, with cell dimensions: a = 5.5720(10) Å, b = 21.5770(4) Å, c = 11.2330(2) Å, beta = 95.15(3)°, with four molecules per unit cell. The crystal of (III) is monoclinic, space group P2₁/n, with cell dimensions: a = 12.0886(5) Å, b = 7.9103(4), c = 104.29(1) Å, beta = 104.29(1)°, with four molecules per unit cell. Of particular interest is the fact that the C5–N6 bond appears to have a high double bond character in all three of the compounds studied. In addition, it is found that the exocyclic N-phenyl group changes from being in the cis conformation with respect to sulfur in compounds (I) and (III) to the trans conformation in the hydrochloric salt (II).     

Crystal structure of 5-(p-methoxyphenylamino)indane and AM1 calculations on N-arylamines derivatives, precursors of phenothiazine drugs

The structural determination by X-ray crystallography of the titled N-arylamine 4a, as well as AM₁ calculations on a series of derivatives (4b–c, 5a–c), are reported. The compound 4a is monoclinic P2₁/c with a = 7.656(3), b = 23.655(5), c = 7.686(9) Å, = 112.59(6)°, V = 1285.2(2) ų and Z = 4. This structure has been used as a template for the building of some others derivatives used for AM₁ calculations. The results show that the cyclization position on the aromatic rings, which can lead to two regioisomers, depends on the nature of the benzylic substituants.     

Crystal structure and spectroscopy of a new dmg2−-bridged dinuclear cobalt(III) compound

A new dinuclear complex of formula [Co₂(dien)₂(dmg)₂](ClO₄)₂4.5H₂O (dien = diethlyenetriamine, dmg^2– = dianion of dimethylglyoxime) has been synthesized and characterized by single crystal X-ray diffraction analysis. It crystallizes in the monoclinic space group c2/c, with a = 20.868(7) Å, b = 11.408(4) Å, c = 15.816(4) Å, = 116.97(2), V = 3355.8(17) ų, Z = 4, F(000) = 1732. The structure consists of a dmg^2–-bridged Co(III) dimer. The coordination environments of two Co(III) ions are identical. Each cobalt(III) ion is coordinated by five nitrogen of one dien molecule and one dmg^2– ligand, and the coordination sphere is completed by an oxygen atom of the bridging dmg^2–. The compound is characterized by means of room temperature magnetic susceptibility measurement and infrared spectroscopy.     

X-ray crystal and molecular structure of 2,3-dideoxy-4-thio-d-arabino-heptonic acid 1,4-lactone: a key intermediate for syntheses of 2′, 3′-dideoxy-4′-thio-l-nucleosides

The structure of 2,3-dideoxy-4-thio-d-arabino-heptonic acid 1,4-lactone has been determined by X-ray diffraction. Crystals of the compound are orthorhombic, space groupP2₁2₁2₁, with cell dimensionsa=11.555(5),b=10.451(5),c=9.604(5) Å, andZ=4. The diffraction experiment has allowed to assign the absolute configuration (4R, 5R, 6R) to the chiral centers of the molecule.     

Crystal structure of 1,7-dihydroxyxanthone from <Emphasis Type="Italic">Weddellina squamulosa</Emphasis> Tul

1,7-dihydroxyxanthone was isolated from Weddellina squamulosa Tul. (Podostemaceae) and the crystal structure has been determined (C₁₃H₈O₄), Mr = 228.19, a = 4.902(1), b = 13.593(4), c = 14.740(2) Å, space group P2₁2₁2₁, Z = 4, and V = 982.2(4) ų. The 1,7-dihydroxyxanthone molecule is planar with a strong intramolecular H-bond O–HsO [2.607(4) Å]. The molecular packing is done through hydrogen bonds O–HsO [2.786(4) Å], forming channels along the direction parallel to the a-axis.