X-Ray Crystal Structure of Betulin–DMSO Solvate

Abstract  

Betulin is a lupane triterpenoid [lup-20(29)-ene-3β,28-diol, C₃₀H₅₀O₂] showing high biological activity. This activity is supposed to be strongly affected by the molecular structure of its polymorphic forms. Different solvate polymorphic forms of betulin have aroused increasing interest as the possible anticancer agents of natural origin. X-ray diffraction was used to investigate crystal structure of (1:1) betulin–DMSO solvate. Title compound crystallizes in the orthorhombic P2₁2₁2₁ space group. Unit cell parameters are as follows: a = 7.0006(2) ?, b = 12.1623(3) ?, c = 33.6991(8) ?, Z = 4. Crystal packing and selected geometric parameters are described. It has been found that the hydrogen bonding and the dipole–dipole interaction between DMSO molecules play the major role in the formation of the crystal structure.     

Synthesis,Crystal Structure,Antioxidant, and α-Glucosidase Inhibitory Activities of Methoxy-substituted Benzohydrazide Derivatives

Eight methoxy substituted at the benzylidene moiety benzohydrazide derivatives [R = 2-OCH₃ (1), 3-OCH₃ (2), 4-OCH₃ (3), 2,3-(OCH₃)₂ (4), 3,4-(OCH₃)₂ (5), 2,4,5-(OCH₃)₃ (6), 2,4,6-(OCH₃)₃ (7), and 3,4,5-(OCH₃)₃ (8)] were synthesized and characterized by ¹H NMR, FT-IR and UV-Vis spectroscopy. The crystal structure of 4 was determined by single crystal X-ray diffraction (sp. gr. Pbca, Z = 8). The molecule is slightly twisted with the dihedral angle between the two phenyl rings being 9.33(14)°. The methoxy group at the ortho position is twisted [C–O–C–C angle is–109.2(3)°] whereas the other at meta position is co-planar with the attached benzene ring. In the crystal packing, the molecules are linked into two-dimensional network parallel to the (001) plane by O–H···O, O–H···N, and N–H···O hydrogen bonds. Compounds 1–8 were evaluated for an antioxidant and α-glucosidase inhibitory activities and the results suggested that the ?OCH₃ substituent was ineffective for bioactivity enhancement.     

Synthesis and Crystal Structure Analysis of 9-Phenyl-β-carboline

An efficient method is described for the synthesis of 9-phenyl-9H-pyrido[3,4-b]indole and 9-(4-chlorophenyl)-9H-pyrido[3,4-b]indole by employing a catalytic amount of CuI (10 mole%) without any ligand. The single crystal of 9-phenyl-9H-pyrido[3,4-b]indole was produced by crystallization from hexane and ethyl acetate mixture that was investigated by single X-ray diffraction (XRD). The compound crystallizes in monoclinic P21/c space group with unit cell dimensions a = 11.3132(5) Å, b = 12.0061(5) Å, c = 9.2498(4) Å, α = 90°, β = 103.187(3)°, γ = 90°. ¹H and ¹³C NMR, IR, and mass spectroscopic methods of the compounds are also discussed.     

Synthesis,Crystal Structure and Characterization of (Z)-2-N′-hydroxyisonicotinamidine

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by ¹H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C₆H₇N₃O is crystallized in the orthorhombic crystal system with the space group Pna2₁ and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.     

Synthesis and Crystal Structure of 3-Quinuclidinyl α-(Cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate

Abstract The title compound 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane. Its structure was characterized by ¹H, ¹³C NMR, MS and X-ray single-crystal diffraction techniques: C₂₀H₂₅NO₃, M _r = 327.41, orthorhombic, space group P2₁2₁2₁ with a = 8.547(2), b = 11.428(4), c = 18.288(5) ?, V = 1786.3(9) ?³, Z = 4. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds. Index Abstract The title compound, 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane and its crystal structure determined. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds.      

Synthesis and Crystal Structure of the Salt [PPN+]2[Cu2I2Cl2]2−

Abstract The synthesis of the PPN (PPN=Ph₃P=N=PPh₃) salt of di-μ-iodo-dichlorocuprate (I) anion [Cu₂I₂Cl₂]²⁻ is described and the crystal and molecular structures of this compound are reported. It was found that the compound has the formula [PPN]₂[Cu₂I₂Cl₂]_0.7[Cu₂I₄]_0.3 (3). Compound 3 crystallizes in an orthorhombic crystal system, space group Pbca, with a = 19.654(3), b = 16.130(2), c = 20.108(3) ?, V = 6374.3(16) ?³ and Z = 4. The crystal contains 70% [Cu₂I₂Cl₂]²⁻ anions and 30% [Cu₂I₄]²⁻ anions. This was also confirmed by MSES spectroscopy. The anion [Cu₂I₂Cl₂]²⁻ is planar and the Cu atoms have a trigonal planar configuration. Graphical abstract Synthesis and Crystal Structure of the Salt [PPN ⁺ ] ₂ [Cu ₂ I ₂ Cl ₂ ] ²⁻ Andrey A. Yakovenko, Tatiana V. Timofeeva and Mikhail Yu. Antipin The title compound was synthesized and structurally investigated. The crystal contains 70% [Cu₂I₂Cl₂]²⁻ anions and 30% [Cu₂I₄]²⁻ anions. This was confirmed by MS ES spectroscopy.      

Crystal structure of the low-temperature modification of α-RbB3O5

The crystal structure of α-RbB₃O₅ was refined by the Rietveld method with due regard for anisotropic vibrations of rubidium atoms to R _p = 2.93, R _wp = 3.80, R _B = 2.53, R _F = 2.84, and s = 1.54. The compound is isostructural to CsB₃O₅: it is orthorhombic, sp. gr. P2₁2₁2₁, a = 8.209(1), b = 10.092(1), c = 5.382(1) Å, and V = 445.9 Å 3. The framework structure is formed by the boron-oxygen [B ₂ ^III B^IVO₅] ^? rings consisting of two [BO₃]-triangles and a [BO₄]-tetrahedron. The rings are linked to form systems of helical chains running along the twofold screw axes parallel 2₁ to the a-and b-axes and infinite channels parallel to the a-and c-axes, which accommodate Rb atoms. The data were collected on an ADP-2 diffractometer [CuK _α radiation, Ni-filter, 12.00° < 2θ < 110.00°, a step in 2θ equal to 0.02°, count time 8 s per step, and 711 reflections α₁ + α₂)]. All the calculations were performed using version 3.3 of the WYRIET program. The comparison of the structures of α-and β-RbB₃O₅ and CsB₃O₅ revealed that the type of deformations in the framework structures of alkali-metal borates due to the changes of the temperature or the substitution of cations is determined by the role played by metal atoms, and especially, by large and heavy ions.     

Crystal structure of the meta hydroxyl phenyl analog of α(+)-prodine

The meta hydroxyphenyl analog of -prodine (1,3-dimethyl-(4-meta-hydroxy phenyl)-4-propionyloxypiperidine) free base crystallizes in the orthorhombic space group P2₁2₁2₁. The relative configuration of the compound shows the piperidine ring is in a chair conformation, the phenyl ring, the 3-methyl, and the N-methyl are equatorial, and the 4-propionyloxy group is axial. The molecular structure is similar to that of racemic -prodine and the potent opioid agonist, ketobemidone. There is a hydrogen bond between N(1) ... O(1) 2.79 Å.     

Synthesis and Crystal Structure of γ-Type Octamolybdates Coordinated by Alanines

Abstract  

The acidification of aqueous solutions containing Na₂MoO₄·2H₂O and KCl in the presence of alanine ligand gives an octamolybdate coordinated by two alanine ligands, K₄[Mo₈O₂₆(CH₃CH(NH₃)CO₂)₂]·4H₂O (1), which crystallizes with triclinic symmetry in the space group P[`1] P\overline{1} , the cell parameters being a = 9.0622(10) ?, b = 9.9652(11) ?, c = 10.6322(12) ?, α = 90.021(2)°, β = 100.656(2)°, γ = 106.271 (2)°, V = 904.42(17) ?³, Z = 1, D _c  = 2.920 g cm⁻³ and final R indices (I > 2σ(I)) R ₁ = 0.0257, wR ₂ = 0.0682, S = 1.115. The alanine ligands are coordinated via their carboxylate–oxygen as a monodentate ligand to γ-[Mo₈O₂₆]⁴⁻ anion.     

Crystal Structure of 2-Thiophenecarboxamide: A One-dimensional Tubular Structure Formed by N–H···O Hydrogen Bonds

Abstract  The crystal structure of 2-thoiphenecarboxamide is described. The compound crystallizes in the orthorhombic Pna2₁ space group with unit cell parameters a = 10.044 (3) ?, b = 14.203 (4) ? and c = 15.941 (3) ?; V = 2,274.1 (10) ?³. The asymmetric unit contains four independent molecules which are linked by N–H···O hydrogen bonds. The asymmetric unit at (x, y, z) is connected with another one, produced by the a-glide plane at 0.75 along the b-axis, that lies at (x + 0.5, −y + 1.5, z) by two N–H···O hydrogen bonds and by a C–H···O weak hydrogen bond to form a one-dimensional tube. Adjacent tubes are linked by C–H···pi interactions to form a three-dimensional framework. Graphical Abstract  The crystal structure of 2-thiophenecarboxamide, contains four crystallographically independent molecular components in the asymmetric unit linked by four N–H···O hydrogen bonds and a weak C–H···O hydrogen bond and form a one-dimensional tube. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal Structure and Synthesis of 17α-Acetoxy-pregn-4,6-diene-3,20-dione

Abstract  

17α-Acetoxy-pregn-4,6-diene-3,20-dione (1), C₂₃H₃₀O₄, was synthesized from the commercially available 17α-acetoxyprogesterone. X-ray diffraction analysis of (1) demonstrated that it consists of four rings, three six-membered rings (A, B and C) and one-five-membered ring (D). A, B, C and D rings occur in an envelope; half chair and chair; and half chair conformations, respectively. The crystal of 17α-acetoxy-pregn-4,6-diene-3,20-dione is in orthorhombic crystal system with space group P2₁2₁2₁, lattice constants: a = 10.843(1), b = 11.744(1), c = 15.815(2)?, V = 2013.9(4)?³, Dx = 1.222 g/cm³ and Z = 4. The molecules in the crystal are stabilized by C–H···O interactions and van der Waals forces.     

Search for Helices of Atomic Electron Density As a Structural Basis of Optical Activity in α-TeO2 Crystal

Crystallography Reports - An X-ray diffraction study of the atomic structure of paratellurite (α-TeO2) crystal in the temperature range of 86–500 K has been performed. Regions of atomic...     

Crystal and Molecular Structure of the Nematogenic Compound 4′-Cyanophenyl-4-n-Pentoxybenzoate

The title compound with the formula C₅H₁₁O-C₆H₄-COO-C₆H₄-CN (CPPOB) crystallizes in the orthorhombic space group Pnam with a = 16.465 Å, b = 13.577 Å, c = 7. 621 Å and four molecules per unit cell. The structure has been solved by direct methods and refined to a final R value of 0.050. The CPPOB molecules have exact C_s symmetry as a consequence of their location on crystallographic mirror symmetry planes, the benzene ring to which the cyano group is attatched has a perpendicular orientation to the other ring in the plane. The molecules adopt a nearly optimal stretched form, neighbouring molecules make an angle of 35.2°. The results are discussed in relation to the mesomorphic behaviour of CPPOB.     

Crystal Structure of 3β-Hydroxy-16α-methylpregn-5-en-20-one

Abstract  

The crystal structure of the title compound, 3β-hydroxy-16α-methylpregn-5-en-20-one, C₂₂H₃₄O₂, was determined by direct methods using single crystal X-ray diffraction data. The compound crystallizes in the triclinic space group P1 with unit-cell parameters: a = 6.235(1) ?, b = 6.282(1) ?, c = 12.877(3) ?, α = 96.672(4)°, β = 98.746(4)°, γ = 106.838(4)°, Z = 1. The structure was refined by full-matrix least-squares to R = 0.0573 for 2,196 observed reflections. Rings A and C of the compound are in chair conformation whereas ring B is in half-chair conformation. Ring D is in envelope conformation. The A/B ring junction is quasi-trans, while ring systems B/C and C/D are trans fused about the C8–C9 and C13–C14 bonds, respectively. The steroid nucleus has a small twist, as shown by the C19–C10···C13–C18 pseudo-torsion angle of 8.0°. Molecules are connected via C–H···O hydrogen bonds to form straight chains along the c-axis of the unit cell. The straight chains are packed together to form layers.     

Synthesis and Crystal Structure of a New Heterotrinuclear Schiff-Base Zn–Gd Complex

Abstract  

A heterotrinuclear Zn–Gd complex [GdZn₂L₂(OAc)₂](CF₃SO₃) (1) based on the salphen Schiff-base ligand bis(3-methoxysalicylidene)-1,2-phenylenediamine (H₂L) was synthesized and characterized by single crystal X-ray diffraction. The structure was solved in the triclinic space group P − 1 with a = 9.4743(19), b = 16.333(3), c = 19.291(4) ?, α = 88.89(3), β = 78.16(2), γ = 76.69(3)°, V = 2842.0(10) ?³, Z = 2, D _c  = 1.610 g/cm³, F (000) = 1,386, R ₁ = 0.0458, and wR ₂ = 0.1239. In the solid state short intermolecular O···H–C hydrogen bonding, π–π stacking, and H···π interactions between neighboring [GdZn₂L₂(OAc)₂]⁺ moieties generate a porous 3D-framework architecture with extended channels running along the a-axis.