Expanding the structural landscape of niclosamide: a highZ′ polymorph, two new solvates and monohydrate HA

2015 ◽  
Vol 71 (5) ◽  
pp. 394-401 ◽  
Author(s):  
Ioana Sovago ◽  
Andrew D. Bond
Keyword(s):  
Hydrogen Bonds ◽  
Short Axis ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Complete Structure ◽  
Acta Cryst ◽  
Oh Groups ◽  
X Ray ◽  
Face To Face ◽  
Solvent Molecules

Three new crystalline phases are reported for the drug niclosamide [5-chloro-N-(2-chloro-4-nitrophenyl)-2-hydroxybenzamide], C13H8Cl2N2O4. A new high-Z′ polymorph (denoted Form II) is described, with four molecules in the asymmetric unit in the space groupP2/n. The structure exhibits pseudosymmetry, including local translations and screw-type operations. The niclosamide molecules are linked by O—H...O hydrogen bonds into chains, and the chains are packed so that the molecules form face-to-face (stacking) and end-to-end interactions within layers perpendicular to the chains. There are two different layer arrangements, giving a structure that is relatively complex. In the acetone and acetonitrile solvates, the incorporated solvent molecules accept hydrogen bonds from the OH groups of niclosamide, and the niclosamide molecules are stacked in a face-to-face manner. In the acetone solvate, C13H8Cl2N2O4·C3H6O, V-shaped arrangements are formed in which the nitrobenzene ends of the niclosamide molecules are brought into face-to-face contact. In the acetonitrile solvate, C13H8Cl2N2O4·CH3CN, stacking occurs by translation along a short axis (ca3.8 Å) and the crystals are frequently observed to be twinned by twofold rotation around that axis. The acetonitrile molecules occupy channels in the structure. A complete structure is provided for niclosamide monohydrate, C13H8Cl2N2O4·H2O, polymorph HA, obtained by Rietveld refinement against laboratory powder X-ray diffraction data. It has been suggested that this compound is related to the methanol solvate of niclosamide [Harriss, Wilson & Radosevljevic Evans (2014).Acta Cryst.C70, 758–763], but it is found that the two are not fully isostructural: they contain isostructural two-dimensional layers, but the layers are arranged differently in the two structures. This suggests that HAmay have the potential for polytypism, and features in the Rietveld difference curve indicate that a polytype fully isostructural with the methanol solvate might be present.

A new polymorph of bis(2-aminopyridinium) fumarate–fumaric acid (1/1) from powder X-ray diffraction

2013 ◽  
Vol 69 (8) ◽  
pp. 896-900 ◽  
Author(s):  
Shuichao Dong ◽  
Yaqiu Tao ◽  
Xiaodong Shen ◽  
Zhigang Pan
Keyword(s):  
Hydrogen Bonds ◽  
Fumaric Acid ◽  
Diffraction Method ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Acta Cryst ◽  
Space Group ◽  
X Ray ◽  
Hydrogen Bonded

A new polymorph of bis(2-aminopyridinium) fumarate–fumaric acid (1/1), 2C5H7N2+·C4H2O42−·C4H4O4, was obtained and its crystal structure determined by powder X-ray diffraction. The new polymorph (form II) crystallizes in the triclinic system (space groupP\overline{1}), while the previous reported polymorph [form I; Ballabh, Trivedi, Dastidar & Suresh (2002).CrystEngComm,4, 135–142; Büyükgüngör, Odabaşoğlu, Albayrak & Lönnecke (2004).Acta Cryst.C60, o470–o472] is monoclinic (space groupP21/c). In both forms I and II, the asymmetric unit consists of one 2-aminopyridinium cation, half a fumaric acid molecule and half a fumarate dianion. The fumarate dianion is involved in hydrogen bonding with two neighbouring 2-aminopyridinium cations to form a hydrogen-bonded trimer in both forms. In form II, the hydrogen-bonded trimers are interlinked across centres of inversionviapairs of N—H...O hydrogen bonds, whereas such trimers are joinedviasingle N—H...O hydrogen bonds in form I, leading to different packing modes for forms I and II. The results demonstrate the relevance and application of the powder diffraction method in the study of polymorphism of organic molecular materials.

scholarly journals Crystal structure of 5-amino-5′-chloro-6-(4-chlorobenzoyl)-8-nitro-2,3-dihydro-1H-spiro[imidazo[1,2-a]pyridine-7,3′-indolin]-2′-one including an unknown solvent molecule

2014 ◽  
Vol 70 (9) ◽  
pp. o971-o972
Author(s):  
R. A. Nagalakshmi ◽  
J. Suresh ◽  
S. Sivakumar ◽  
R. Ranjith Kumar ◽  
P. L. Nilantha Lakshman
Keyword(s):  
Hydrogen Bonds ◽  
Solvent Molecule ◽  
Asymmetric Unit ◽  
Acta Cryst ◽  
Compound C ◽  
Benzoyl Group ◽  
Independent Molecules ◽  
Solvent Molecules ◽  
Intramolecular Hydrogen ◽  
Ring Motif

The asymmetric unit of the title compound, C21H15Cl2N5O4, contains two independent molecules (AandB) having similar conformations. The amine (NH2) group forms an intramolecular hydrogen bond with the benzoyl group, giving anS(6) ring motif in both molecules. The central six-membered rings adopt sofa conformations and the imidazole rings are planar (r.m.s deviations = 0.0150 and 0.0166 Å). The pyridine and imidazole rings are inclined to one another by 3.54 (1) and 3.03 (1)° in moleculesAandB, respectively. In the crystal, molecules are linked by N—H...O hydrogen bonds, forming chains along theaaxis which encloseR22(16) ring motifs. The rings are linked by weak N—H...O and C—H...O hydrogen bonds and C—H...π interactions forming sheets lying parallel to (001). A region of disordered electron density, most probably disordered solvent molecules, occupying voids ofca753 Å3for an electron count of 260, was treated using the SQUEEZE routine inPLATON[Spek (2009).Acta Cryst.D65, 148–155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

scholarly journals Crystal structure, synthesis and thermal properties of bis(4-benzoylpyridine-κN)bis(isothiocyanato-κN)bis(methanol-κN)iron(II)

2020 ◽  
Vol 76 (2) ◽  
pp. 276-280
Author(s):  
Carsten Wellm ◽  
Christian Näther
Keyword(s):  
Crystal Structure ◽  
Thermal Properties ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Aged Sample ◽  
X Ray Diffraction ◽  
Pure Sample ◽  
X Ray ◽  
Structure Synthesis ◽  
Solvent Molecules

In the crystal structure of the title compound, [Fe(NCS)2(C12H9NO)2(CH4O)2], the FeII cations are octahedrally coordinated by two N atoms of 4-benzoylpyridine ligands, two N atoms of two terminal isothiocyanate anions and two methanol molecules into discrete complexes that are located on centres of inversion. These complexes are linked via intermolecular O—H...O hydrogen bonds between the methanol O—H H atoms and the carbonyl O atoms of the 4-benzoylpyridine ligands, forming layers parallel to (101). Powder X-ray diffraction proved that a pure sample was obtained but that this compound is unstable and transforms into an unknown crystalline phase within several weeks. However, the solvent molecules can be removed by heating in a thermobalance, which for the aged sample as well as the title compound leads to the formation of a compound with the composition Fe(NCS)2(4-benzoylpyridine)2, which exhibits a powder pattern that is similar to that of Mn(NCS)2(4-benzoylpyridine)2.

scholarly journals Crystal structures of 5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane cobalt(III) mono-phenylacetylide and bis-phenylacetylide

2018 ◽  
Vol 74 (4) ◽  
pp. 522-529 ◽  
Author(s):  
Benjamin M. Oxley ◽  
Brandon Mash ◽  
Matthias Zeller ◽  
Susannah Banziger ◽  
Tong Ren
Keyword(s):  
Crystal Structures ◽  
Symmetry Operator ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Weak Base ◽  
Monoclinic Symmetry ◽  
X Ray ◽  
Independent Molecules ◽  
Solvent Molecules ◽  
Occupancy Rates

Reported in this contribution are the synthesis and crystal structures of new mono- and bis-phenylacetylides based on CoIII(DMC) (DMC is 5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane). Chlorido(5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane)(phenylethynyl)cobalt(III) chloride–acetonitrile–methanol (1/1/1), [Co(C8H5)Cl(C12H28N4)]Cl·CH3CN·CH3OH, 1, and (5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane)bis(phenylethynyl)cobalt(III) trifluoromethanesulfonate–dichloromethane (2/1), [Co(C8H5)2(C12H28N4)]2(CF3SO3)2·CH2Cl2, 2, were prepared under weak-base conditions in satisfactory yields. Single-crystal X-ray diffraction studies revealed that both 1 and 2 adopt a pseudo-octahedral symmetry in which the Cl—Co—C angles of 1 and C—Co—C of 2 range from 177.7 (2) to 178.0 (2)° and from 177.67 (9) to 179.67 (9)°, respectively. In both structures, the CoIII metal center is coordinated in the equatorial plane by four N atoms, in which the N—Co—N angles range from 85.6 (3) to 94.4 (3)°. The structure of 1 features two crystallographically independent molecules in its triclinic cell (Z′ = 2), which are related to each other by pseudo-monoclinic symmetry. The crystal investigated was twinned by a symmetry operator of the approximate double-volume C-centered cell (180° rotation around [201] of the actual triclinic cell), with a refined twin ratio of 0.798 (3) to 0.202 (3). Both methanol solvent molecules in 1 are disordered, the major occupancy rates refined to 0.643 (16) and 0.357 (16). Compound 2 also contains two molecules in the asymmetric unit, together with two trifluoromethanesulfonate anions [of which one is disordered; occupancy values of 0.503 (16) and 0.497 (16)] and a disordered dichloromethane [occupancy values of 0.545 (12) and 0.455 (12)].

scholarly journals Crystal structure of an unknown solvate of {2,2′-[ethane-1,2-diylbis(nitrilomethanylylidene)]diphenolato-κ4O,N,N′,O′}(N-ferrocenylisonicotinamide-κN1)cobalt(II): a CoII–salen complex that forms hydrogen-bonded dimers

2015 ◽  
Vol 71 (9) ◽  
pp. 1100-1104
Author(s):  
Bryan Brautigam ◽  
Chelsea Herholdt ◽  
William Farnsworth ◽  
Ellen Brudi ◽  
Eric McDonald ◽  
...  
Keyword(s):  
Ring Structure ◽  
X Ray Diffraction ◽  
Acta Cryst ◽  
X Ray ◽  
Pyramidal Geometry ◽  
Salen Complex ◽  
Hydrogen Bonding Interactions ◽  
Solvent Molecules ◽  
Square Pyramidal Geometry ◽  
Hydrogen Bonded

The title compound, [CoFe(C5H5)(C16H14N2O2)(C11H9N2O)], was prepared as an air-stable red–brown solid by mixing equimolar amounts of {2,2′-[ethane-1,2-diylbis(nitrilomethanylylidene)]diphenolato}cobalt(II) andN-ferrocenylisonicotinamide in dry dichloromethane under nitrogen and was characterized by ESI–MS, IR, and single-crystal X-ray diffraction. The structure at 100 K has triclinic (P-1) symmetry and indicates that the complex crystallizes as a mixture of λ and δ conformers. It exhibits the expected square pyramidal geometry about Co, and forms hydrogen-bonded dimers through amide N—H groups and phenolate O atoms on an adjacent molecule. The involvement of only half of the salen ring structure in hydrogen-bonding interactions results in slight folding of the salen ring away from the pyridine coordination site in the δ conformer with an inter-salicylidene fold angle of 9.9 (7)°. In contrast, the λ conformer is nearly planar. The dimers pack into an open structure containing channels filled with highly disordered solvent molecules. These solvent molecules' contributions to the intensity data were removed with the SQUEEZE procedure [Spek (2015).Acta Cryst.C71, 9–18] available inPLATON.

scholarly journals Crystal structure of 7′-(4-chlorophenyl)-2′′-(4-methoxyphenyl)-7′,7a',7′′,8′′-tetrahydro-1′H,3′H,5′′H-dispiro[indoline-3,5′-pyrrolo[1,2-c]thiazole-6′,6′′-quinoline]-2,5′′-dione and an unknown solvent

2019 ◽  
Vol 75 (2) ◽  
pp. 189-193
Author(s):  
R. Vishnupriya ◽  
M. Venkateshan ◽  
J. Suresh ◽  
R. V. Sumesh ◽  
R. Ranjith Kumar ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Chair Conformation ◽  
Ring System ◽  
Supramolecular Framework ◽  
Asymmetric Unit ◽  
Acta Cryst ◽  
Π Interactions ◽  
Compound C ◽  
Independent Molecules ◽  
Solvent Molecules

The asymmetric unit of the title compound, C34H28ClN3O3S, contains two independent molecules (A and B). They differ essentially in the orientation of the 4-methoxyphenyl ring with respect to the pyridine ring of the quinoline moiety; this dihedral angle is 37.01 (18)° in molecule A but only 7.06 (17)° in molecule B. In both molecules, the cyclohexanone ring of the isoquinoline unit has a half-chair conformation. In the pyrrolothiazole ring system, the pyrrolo ring in molecule A has a twisted conformation on the N—C fused bond and an envelope conformation in molecule B with the N atom as the flap. The thiazole rings of both molecules have twisted conformations on the N—C fused bond. In the crystal, the A molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif. These dimers are linked to the B molecules by an N—H...N hydrogen bond and a series of C—H...O hydrogen bonds, forming layers lying parallel to the (101) plane. The layers are linked by C—H...π interactions and offset π–π interactions [intercentroid distance = 3.427 (1) Å], forming a supramolecular framework. The contribution to the scattering from a region of highly disordered solvent molecules was removed with the SQUEEZE routine in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. The solvent formula mass and unit-cell characteristics were not taken into account during refinement.

Synthesis, structure and biological activity of four new picolinohydrazonamide derivatives

2020 ◽  
Vol 76 (7) ◽  
pp. 673-680
Author(s):  
Małgorzata Szczesio ◽  
Katarzyna Gobis ◽  
Izabela Korona-Głowniak ◽  
Ida Mazerant-Politowicz ◽  
Dagmara Ziembicka ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Biological Activity ◽  
Nmr Spectroscopy ◽  
Low Temperature ◽  
Hydrogen Bonds ◽  
Essential Role ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zwitterionic Form ◽  
Solvent Molecules

Four new picolinohydrazonamide derivatives, namely, 6-methyl-N′-(morpholine-4-carbonothioyl)picolinohydrazonamide, C12H17N5OS, 6-chloro-N′-(morpholine-4-carbonothioyl)picolinohydrazonamide methanol monosolvate, C11H14ClN5OS·CH3OH, 6-chloro-N′-(4-phenylpiperazine-1-carbonothioyl)picolinohydrazonamide, C17H19ClN6S, and 6-chloropicolinohydrazonamide, C6H7ClN4, have been synthesized and characterized by NMR spectroscopy and single-crystal low-temperature X-ray diffraction. In addition, their antibacterial and anti-yeast activities have been determined. The first three compounds adopt the zwitterionic form in the crystal structure regardless of the presence or absence of solvent molecules in the structure. They also adopt the same symmetry, i.e. P21/c (P21/n), unlike the fourth structure which is chiral and has the space group P212121. For all the studied cases, intermolecular N—H...O and N—H...N hydrogen bonds play an essential role in the formation of the structures.

scholarly journals Structural and Computational Studies of 1-Methyl-2-thiocytosine and its Coordination Mode in a Dinuclear Platinum(IV) Complex [(PtMe3)2(μ-1-MeSCy-1κN3,1:2κ2S)2][BF4]2

2010 ◽  
Vol 65 (5) ◽  
pp. 578-s590
Author(s):  
Cornelia Vetter ◽  
Christoph Wagner ◽  
Ralph Kluge ◽  
Dirk Steinborn
Keyword(s):  
Hydrogen Bonds ◽  
Diffraction Analysis ◽  
Coordination Mode ◽  
Complex Cation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Face To Face ◽  
Dinuclear Platinum ◽  
Network Of Hydrogen Bonds ◽  
Equilibrium Structures

X-Ray diffraction analysis of 1-methyl-2-thiocytosine (1-MeSCy, 1) revealed that its crystals contain two structurally very similar independent molecules (A, B). These molecules are connected through a complex network of hydrogen bonds. Centrosymmetric di- and tetrameric units AAʹ and BAAʹBʹ, respectively, are formed through N-H...N hydrogen bonds (N4a...N3aʹ 3.019(4) Å , AAʹ; N4a...N3b 2.988(4) Å, BAAʹBʹ), and the tetrameric units are connected through N-H...S hydrogen bonds. The arrangement of A and B molecules found in crystals of 1 was confirmed by DFT calculations up to tetrameric BAAʹBʹ units, yielding similar equilibrium structures, and the energies of the N-H...N hydrogen bonds between A and Aʹ and A and B were calculated to be about 10 kcal mol−1. Reaction of 1-MeSCy (1) with [PtMe3(Me2CO)3][BF4] (2) led to the formation of the ionic dinuclear complex [(PtMe3)2(μ-1-MeSCy-1κN3,1:2κ2S)2][BF4]2 (3) which was fully characterized by NMR (1H, 13C, 195Pt) and IR spectroscopy, ESI mass spectrometry and microanalysis. A singlecrystal X-ray diffraction analysis of 3 confirmed the dinuclear structure of the complex. The complex cation consists of a central [Pt2(μ-S)2] core having bound the 1-methyl-2-thiocytosine ligands in a 1κN3,1:2κ2S coordination mode in a face-to-face arrangement, the thionucleobase ligands being present as the amino-thione tautomer.

scholarly journals Molecular and crystal structure of gossypol tetramethyl ether with an unknown solvate

2015 ◽  
Vol 71 (2) ◽  
pp. 184-187 ◽  
Author(s):  
Muhabbat Honkeldieva ◽  
Samat Talipov ◽  
Rustam Mardanov ◽  
Bakhtiyar Ibragimov
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Rotation Axis ◽  
Dimethyl Sulfate ◽  
Asymmetric Unit ◽  
Acta Cryst ◽  
Compound C ◽  
Scattering Contribution ◽  
Solvent Molecules ◽  
Hydroxy Groups

The title compound, C34H38O8(systematic name: 5,5′-diisopropyl-2,2′,3,3′-tetramethoxy-7,7′-dimethyl-2H,2′H-8,8′-bi[naphtho[1,8-bc]furan]-4,4′-diol), has been obtained from a gossypol solution in a mixture of dimethyl sulfate and methanol. The molecule is situated on a twofold rotation axis, so the asymmetric unit contains one half-molecule. In the molecule, the hydroxy groups are involved in intramolecular O—H...O hydrogen bonds, and the two naphthyl fragments are inclined each to other by 83.8 (1)°. In the crystal, weak C—H...O and C—H...π interactions consolidate the packing, which exhibits channels with an approximate diameter of 6 Å extending along thec-axis direction. These channels are filled with highly disordered solvent molecules, so their estimated scattering contribution was subtracted from the observed diffraction data using the SQUEEZE option inPLATON[Spek, A. L. (2015).Acta Cryst. C71, 9–18].

Synthesis and Structural Studies of 5, 11, 17, 23-Tetrahydroxyresorc[4]arenes

2001 ◽  
Vol 56 (10) ◽  
pp. 1063-1073 ◽  
Author(s):  
Thorsten Gerkensmeier ◽  
Ceno Agena ◽  
Waldemar Iwanek ◽  
Roland Fröhlich ◽  
Sirpa Kotila ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Single Crystal ◽  
Double Layers ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Molecules

Hydroxyresorc[4]arenes are bowl-shaped calixarene compounds. Herein we report the synthesis and the results of X-ray diffraction examinations of six hydroxyresorc[4]arenes, one of them could be crystallized in two conformations. All compounds co-crystallize with different solvent molecules, linked together by hydrogen bonds. It is known that hydroxyresorc[4]arenes are capable of forming large aggregates, a number of different compounds have been prepared, some of them could be crystallized and investigated by single crystal methods. Most of the compounds tend to form polarity-induced double layers.

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