and Ancient tsunami may have struck Falkland Islands - BBC News By www.bbc.com Published On :: Mon, 16 Mar 2020 07:00:00 GMT Ancient tsunami may have struck Falkland Islands BBC News Full Article
and Expert confirms true impact of earthquakes in Devon and Cornwall - Devon Live By www.devonlive.com Published On :: Sat, 07 Dec 2019 08:00:00 GMT Expert confirms true impact of earthquakes in Devon and Cornwall Devon Live Full Article
and Two earthquakes felt by residents in Lochaber - Press and Journal By www.pressandjournal.co.uk Published On :: Thu, 14 Nov 2019 08:00:00 GMT Two earthquakes felt by residents in Lochaber Press and Journal Full Article
and Coronavirus shock: Pandemic lockdowns have changed how the planet SOUNDS and vibrates - Express.co.uk By www.express.co.uk Published On :: Wed, 01 Apr 2020 07:00:00 GMT Coronavirus shock: Pandemic lockdowns have changed how the planet SOUNDS and vibrates Express.co.uk Full Article
and Impacts on groundwater quality from abandoned hydrocarbon wells - GOV.UK By www.gov.uk Published On :: Tue, 22 Oct 2019 07:00:00 GMT Impacts on groundwater quality from abandoned hydrocarbon wells GOV.UK Full Article
and What is a sinkhole and are they caused by bad weather? - expressandstar.com By www.expressandstar.com Published On :: Mon, 10 Feb 2020 08:00:00 GMT What is a sinkhole and are they caused by bad weather? expressandstar.com Full Article
and Holderness coast: Major cliff landslides 'every six years' - BBC News By www.bbc.com Published On :: Fri, 24 May 2019 07:00:00 GMT Holderness coast: Major cliff landslides 'every six years' BBC News Full Article
and Northampton's first ever earthquake...but did anyone even notice? - Northampton Chronicle and Echo By www.northamptonchron.co.uk Published On :: Mon, 03 Feb 2020 08:00:00 GMT Northampton's first ever earthquake...but did anyone even notice? Northampton Chronicle and Echo Full Article
and Scottish researchers win £12m CCUS funding from European pot - News for the Oil and Gas Sector - Energy Voice By www.energyvoice.com Published On :: Mon, 02 Dec 2019 08:00:00 GMT Scottish researchers win £12m CCUS funding from European pot - News for the Oil and Gas Sector Energy Voice Full Article
and Scottish Highlands hit by earthquake with magnitude measuring 2.3 - The Scottish Sun By www.thescottishsun.co.uk Published On :: Tue, 07 Jan 2020 08:00:00 GMT Scottish Highlands hit by earthquake with magnitude measuring 2.3 The Scottish Sun Full Article
and Earthquake strikes the west Highlands - Press and Journal By www.pressandjournal.co.uk Published On :: Wed, 08 Jan 2020 08:00:00 GMT Earthquake strikes the west Highlands Press and Journal Full Article
and Second earthquake recorded this year in Northamptonshire - Northampton Chronicle and Echo By www.northamptonchron.co.uk Published On :: Sat, 04 Apr 2020 07:00:00 GMT Second earthquake recorded this year in Northamptonshire Northampton Chronicle and Echo Full Article
and Geologists discover hundreds of buried valleys throughout Britain - Press and Journal By www.pressandjournal.co.uk Published On :: Thu, 04 Jul 2019 07:00:00 GMT Geologists discover hundreds of buried valleys throughout Britain Press and Journal Full Article
and Kendalian Dr Kent Brooks trained new director of British Geological Survey - The Westmorland Gazette By www.thewestmorlandgazette.co.uk Published On :: Fri, 19 Jul 2019 07:00:00 GMT Kendalian Dr Kent Brooks trained new director of British Geological Survey The Westmorland Gazette Full Article
and Ancient underwater landslides help Brit scientists predict tsunamis - Metro.co.uk By metro.co.uk Published On :: Fri, 24 Apr 2020 07:16:08 GMT Ancient underwater landslides help Brit scientists predict tsunamis Metro.co.uk Full Article
and Climate change and urbanisation 'threaten groundwater', say scientists - ENDS Report By www.endsreport.com Published On :: Mon, 20 Apr 2020 07:00:00 GMT Climate change and urbanisation 'threaten groundwater', say scientists ENDS Report Full Article
and Ancient underwater landslides help predict tsunami risk - Aberdeen Evening Express By www.eveningexpress.co.uk Published On :: Thu, 23 Apr 2020 07:00:00 GMT Ancient underwater landslides help predict tsunami risk Aberdeen Evening Express Full Article
and Characterization of the Pseudomonas aeruginosa T6SS PldB immunity proteins PA5086, PA5087 and PA5088 explains a novel stockpiling mechanism By scripts.iucr.org Published On :: 2020-04-28 The bacterial type VI secretion system (T6SS) secretes many toxic effectors to gain advantage in interbacterial competition and for eukaryotic host infection. The cognate immunity proteins of these effectors protect bacteria from their own effectors. PldB is a T6SS trans-kingdom effector in Pseudomonas aeruginosa that can infect both prokaryotic and eukaryotic cells. Three proteins, PA5086, PA5087 and PA5088, are employed to suppress the toxicity of PldB-family proteins. The structures of PA5087 and PA5088 have previously been reported, but the identification of further distinctions between these immunity proteins is needed. Here, the crystal structure of PA5086 is reported at 1.90 Å resolution. A structural comparison of the three PldB immunity proteins showed vast divergences in their electrostatic potential surfaces. This interesting phenomenon provides an explanation of the stockpiling mechanism of T6SS immunity proteins. Full Article text
and Crystallographic snapshots of the EF-hand protein MCFD2 complexed with the intracellular lectin ERGIC-53 involved in glycoprotein transport By scripts.iucr.org Published On :: 2020-04-29 The transmembrane intracellular lectin ER–Golgi intermediate compartment protein 53 (ERGIC-53) and the soluble EF-hand multiple coagulation factor deficiency protein 2 (MCFD2) form a complex that functions as a cargo receptor, trafficking various glycoproteins between the endoplasmic reticulum (ER) and the Golgi apparatus. It has been demonstrated that the carbohydrate-recognition domain (CRD) of ERGIC-53 (ERGIC-53CRD) interacts with N-linked glycans on cargo glycoproteins, whereas MCFD2 recognizes polypeptide segments of cargo glycoproteins. Crystal structures of ERGIC-53CRD complexed with MCFD2 and mannosyl oligosaccharides have revealed protein–protein and protein–sugar binding modes. In contrast, the polypeptide-recognition mechanism of MCFD2 remains largely unknown. Here, a 1.60 Å resolution crystal structure of the ERGIC-53CRD–MCFD2 complex is reported, along with three other crystal forms. Comparison of these structures with those previously reported reveal that MCFD2, but not ERGIC-53–CRD, exhibits significant conformational plasticity that may be relevant to its accommodation of various polypeptide ligands. Full Article text
and Structure of the 4-hydroxy-tetrahydrodipicolinate synthase from the thermoacidophilic methanotroph Methylacidiphilum fumariolicum SolV and the phylogeny of the aminotransferase pathway By scripts.iucr.org Published On :: 2020-04-28 The enzyme 4-hydroxy-tetrahydrodipicolinate synthase (DapA) is involved in the production of lysine and precursor molecules for peptidoglycan synthesis. In a multistep reaction, DapA converts pyruvate and l-aspartate-4-semialdehyde to 4-hydroxy-2,3,4,5-tetrahydrodipicolinic acid. In many organisms, lysine binds allosterically to DapA, causing negative feedback, thus making the enzyme an important regulatory component of the pathway. Here, the 2.1 Å resolution crystal structure of DapA from the thermoacidophilic methanotroph Methylacidiphilum fumariolicum SolV is reported. The enzyme crystallized as a contaminant of a protein preparation from native biomass. Genome analysis reveals that M. fumariolicum SolV utilizes the recently discovered aminotransferase pathway for lysine biosynthesis. Phylogenetic analyses of the genes involved in this pathway shed new light on the distribution of this pathway across the three domains of life. Full Article text
and Chirality in Biological Nanospaces: Reactions in Active Sites. By Nilashis Nandi. Pp. 209. CRC Press, 2011. Price £79.99. ISBN 9781439840023. By journals.iucr.org Published On :: Full Article text
and Visualization Bench for the screening of crystallization assays and the automation of in situ experiments By journals.iucr.org Published On :: Full Article text
and Solution structure and assembly of β-amylase 2 from Arabidopsis thaliana By journals.iucr.org Published On :: Solution structure of β-amylase 2 from Arabidopsis thaliana shows the role of the conserved N-terminus in enzyme tetramer formation. Full Article text
and Industrial cryo-EM facility setup and management By journals.iucr.org Published On :: The setup and operation of an industrial cryo-EM laboratory is described. Full Article text
and Sample deposition onto cryo-EM grids: from sprays to jets and back By journals.iucr.org Published On :: Sample preparation within single-particle cryo-electron microscopy can still be a significant bottleneck, with issues in reproducibility, ice quality and sample loss. New approaches have recently been reported that use spraying or pin printing instead of the traditional blotting approach. Here, experience in the use of different nozzle designs and spraying regimes is reported together with their influence on the resulting spray and grid quality. Full Article text
and Scaling diffraction data in the DIALS software package: algorithms and new approaches for multi-crystal scaling By journals.iucr.org Published On :: A new scaling program is presented with new features to support multi-sweep workflows and analysis within the DIALS software package. Full Article text
and Development of basic building blocks for cryo-EM: the emcore and emvis software libraries By journals.iucr.org Published On :: This article presents an overview of the development of two basic software libraries for image manipulation and data visualization in cryo-EM: emcore and emvis. Full Article text
and Crystal and solution structures of fragments of the human leucocyte common antigen-related protein By journals.iucr.org Published On :: The crystal and solution SAXS structures of a fragment of human leucocyte common antigen-related protein show that it is less flexible than the homologous proteins tyrosine phosphatase receptors δ and σ. Full Article text
and Structural and thermodynamic analysis of interactions between death-associated protein kinase 1 and anthraquinones By journals.iucr.org Published On :: Death-associated protein kinase 1 (DAPK1) was found to form a complex with purpurin and the crystal structure of the complex was determined. Purpurin may be a good lead compound for for the discovery of inhibitors of DAPK1. Full Article text
and Structure of Thermococcus litoralis Δ1-pyrroline-2-carboxylate reductase in complex with NADH and L-proline By journals.iucr.org Published On :: The paper reports the structure of a Δ1-pyrroline-2-carboxylate reductase from the archaeon Thermococcus litoralis, a key enzyme involved in the second step of trans-4-Hydroxy-L-proline metabolism, conserved in archaea, bacteria and humans. Full Article text
and Crystal structure of a salt with a protonated sugar cation and a cobalt(II) complex anion: (GlcN–H, K)[Co(NCS)4]·2H2O By scripts.iucr.org Published On :: 2019-09-06 The title compound, d-(+)-glucosammonium potassium tetrathiocyanatocobaltate(II) dihydrate, K(C6H14NO5)[Co(NCS)4]·2H2O or (GlcNH)(K)[Co(NCS)4]·2H2O, has been obtained as a side product of an incomplete salt metathesis reaction of d-(+)-glucosamine hydrochloride (GlcN·HCl) and K2[Co(NCS)4]. The asymmetric unit contains a d-(+)-glucosammonium cation, a potassium cation, a tetraisothiocyanatocobalt(II) complex anion and two water molecules. The water molecules coordinate to the potassium cation, which is further coordinated via three short K+⋯SCN− contacts involving three [Co(NCS)4]2− complex anions and via three O atoms of two d-(+)-glucosammonium cations, leading to an overall eightfold coordination around the potassium cation. Hydrogen-bonding interactions between the building blocks consolidate the three-dimensional arrangement. Full Article text
and 1:1 Co-crystal of 3-ethyl-4-methyl-3-pyrrolin-2-one and 3-ethyl-4-methyl-3-pyrroline-2,5-dione By scripts.iucr.org Published On :: 2019-09-10 Crystallization from a 20-year-old commercial source of 3-ethyl-4-methyl-3-pyrrolin-2-one afforded 1:1 co-crystals of this compound (C7H11NO) with its oxidized derivative, 3-ethyl-4-methyl-3-pyrroline-2,5-dione (C7H9NO2). The compound crystallizes in the space group Poverline{1}, with two molecules of each species in the asymmetric unit. These four molecules form a hydrogen-bonded tetramer with a dimer of 3-ethyl-4-methyl-3-pyrrolin-2-one as the core flanked by one molecule of the dione on each side. Full Article text
and Synthesis and crystal structure of [Cs([2.2.2]crypt)]2[Mo(CO)5] By scripts.iucr.org Published On :: 2019-09-12 Reduction of the heteroleptic metal carbonyl complex Mo(CO)3(η5-Cp)H with the metallic salt Cs5Bi4 in the presence of [2.2.2]crypt (= 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) in liquid ammonia led to single crystals of bis[(4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane)caesium] pentacarbonylmolybdate, [Cs(C18H36N2O6)]2[Mo(CO)5] or [Cs([2.2.2]crypt)]2[Mo(CO)5]. The twofold negatively charged anionic complex corresponds to the 18 valence electron rule. It consists of an Mo atom coordinated by five carbonyl ligands in a shape intermediate between trigonal–bipyramidal and square-pyramidal. The Mo—C distances range from 1.961 (3) to 2.017 (3) Å, and the C≡O distances from 1.164 (3) to 1.180 (4) Å. Full Article text
and Open-access and free articles in IUCrData By journals.iucr.org Published On :: Full Article Still image
and Crystal structure and DFT study of (E)-2-chloro-4-{[2-(2,4-dinitrophenyl)hydrazin-1-ylidene]methyl}phenol acetonitrile hemisolvate By scripts.iucr.org Published On :: 2019-05-10 The title Schiff base compound, C13H9ClN4O5·0.5CH3CN, crystallizes as an acetonitrile hemisolvate; the solvent molecule being located on a twofold rotation axis. The molecule is nearly planar, with a dihedral angle between the two benzene rings of 3.7 (2)°. The configuration about the C=N bond is E, and there is an intramolecular N—H⋯Onitro hydrogen bond present forming an S(6) ring motif. In the crystal, molecules are linked by O—H⋯O and N—H⋯O hydrogen bonds, forming layers lying parallel to (10overline{1}). The layers are linked by C—H⋯Cl hydrogen bonds, forming a supramolecular framework. Within the framework there are offset π–π stacking interactions [intercentroid distance = 3.833 (2) Å] present involving inversion-related molecules. The DFT study shows that the HOMO and LUMO are localized in the plane extending from the phenol ring to the 2,4-dinitrobenzene ring, and the HOMO–LUMO gap is found to be 0.13061 a.u. Full Article text
and Crystal structure and Hirshfeld surface analysis of 4-[4-(1H-benzo[d]imidazol-2-yl)phenoxy]phthalonitrile dimethyl sulfoxide monosolvate By scripts.iucr.org Published On :: 2019-05-10 This work presents the synthesis and structural characterization of [4-(1H-benzo[d]imidazol-2-yl)phenoxy]phthalonitrile, a phthalonitrile derivative carrying a benzimidazole moiety. The compound crystallizes as its dimethyl sulfoxide monosolvate, C21H12N4O·(CH3)2SO. The dihedral angle between the two fused rings in the heterocyclic ring system is 2.11 (1)°, while the phenyl ring attached to the imidazole moiety is inclined by 20.7 (1)° to the latter. In the crystal structure, adjacent molecules are connected by pairs of weak intermolecular C—H⋯N hydrogen bonds into inversion dimers. N—H⋯O and C—H⋯O hydrogen bonds with R21(7) graph-set motifs are also formed between the organic molecule and the disordered dimethyl sulfoxide solvent [occupancy ratio of 0.623 (5):0.377 (5) for the two sites of the sulfur atom]. Hirshfeld surface analysis and fingerprint plots were used to investigate the intermolecular interactions in the crystalline state. Full Article text
and Crystal structure, Hirshfeld surface analysis and HOMO–LUMO analysis of (E)-N'-(3-hydroxy-4-methoxybenzylidene)nicotinohydrazide monohydrate By scripts.iucr.org Published On :: 2019-05-14 The molecule of the title Schiff base compound, C14H13N3O3·H2O, displays a trans configuration with respect to the C=N bond. The dihedral angle between the benzene and pyridine rings is 29.63 (7)°. The crystal structure features intermolecular N—H⋯O, C—H⋯O, O—H⋯O and O—H⋯N hydrogen-bonding interactions, leading to the formation of a supramolecular framework. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (37.0%), O⋯H/H⋯O (23.7%)), C⋯H/H⋯C (17.6%) and N⋯H/H⋯N (11.9%) interactions. The title compound has also been characterized by frontier molecular orbital analysis. Full Article text
and Crystal structure and Hirshfeld surface analysis of a conformationally unsymmetrical bischalcone: (1E,4E)-1,5-bis(4-bromophenyl)penta-1,4-dien-3-one By scripts.iucr.org Published On :: 2019-05-10 In the title bischalcone, C17H12Br2O, the olefinic double bonds are almost coplanar with their attached 4-bromophenyl rings [torsion angles = −10.2 (4) and −6.2 (4)°], while the carbonyl double bond is in an s-trans conformation with with respect to one of the C=C bonds and an s-cis conformation with respect to the other [C=C—C=O = 160.7 (3) and −15.2 (4)°, respectively]. The dihedral angle between the 4-bromophenyl rings is 51.56 (2)°. In the crystal, molecules are linked into a zigzag chain propagating along [001] by weak C—H⋯π interactions. The conformations of related bischalcones are surveyed and a Hirshfeld surface analysis is used to investigate and quantify the intermolecular contacts. Full Article text
and N-[2-(Trifluoromethyl)phenyl]maleamic acid: crystal structure and Hirshfeld surface analysis By scripts.iucr.org Published On :: 2019-05-10 The title molecule, C11H8F3NO3, adopts a cis configuration across the –C=C– double bond in the side chain and the dihedral angle between the phenyl ring and side chain is 47.35 (1)°. The –COOH group adopts a syn conformation (O=C—O—H = 0°), unlike the anti conformation observed in related maleamic acids. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds are connected via N—H⋯O hydrogen bonds and C—H⋯O interactions into (100) sheets, which are cross-linked by another C—H⋯O interaction to result in a three-dimensional network. The Hirshfeld surface fingerprint plots show that the highest contribution to surface contacts arises from O⋯H/H⋯O contacts (26.5%) followed by H⋯F/F⋯H (23.4%) and H⋯H (17.3%). Full Article text
and Crystal structure and Hirshfeld surface analysis of (Z)-6-[(2-hydroxy-4-methylanilino)methylidene]-4-methylcyclohexa-2,4-dien-1-one By scripts.iucr.org Published On :: 2019-05-14 The title compound, C15H15NO2, is a Schiff base that exists in the keto–enamine tautomeric form and adopts a Z configuration. The molecule is almost planar, with the two phenyl rings twisted relative to each other by 9.60 (18)°. There is an intramolecular N—H⋯O hydrogen bond present forming an S(6) ring motif. In the crystal, pairs of O—H⋯O hydrogen bonds link adjacent molecules into inversion dimers with an R22(18) ring motif. The dimers are linked by very weak π–π interactions, forming layers parallel to (overline{2}01). Hirshfeld surface analysis, two-dimensional fingerprint plots and the molecular electrostatic potential surfaces were used to analyse the intermolecular interactions, indicating that the most important contributions for the crystal packing are from H⋯H (55.2%), C⋯H/H⋯C (22.3%) and O⋯H/H⋯O (13.6%) interactions. Full Article text
and Crystal structures and Hirshfeld surface analyses of 4,4'-{[1,3-phenylenebis(methylene)]bis(oxy)}bis(3-methoxybenzaldehyde) and 4,4'-{[(1,4-phenylenebis(methylene)]bis(oxy)}bis( By scripts.iucr.org Published On :: 2019-05-24 The title compounds, C24H22O6 (I) and C24H22O6 (II), each crystallize with half a molecule in the asymmetric unit. The whole molecule of compound (I) is generated by twofold rotation symmetry, the twofold axis bisecting the central benzene ring. The whole molecule of compound (II) is generated by inversion symmetry, the central benzene ring being located on an inversion center. In (I), the outer benzene rings are inclined to each other by 59.96 (10)° and by 36.74 (9)° to the central benzene ring. The corresponding dihedral angles in (II) are 0.0 and 89.87 (12)°. In the crystal of (I), molecules are linked by C—H⋯O hydrogen bonds and C—H⋯π interactions, forming ribbons propagating along the [10overline{1}] direction. In the crystal of (II), molecules are linked by C—H⋯O hydrogen bonds, forming a supramolecular framework. The Hirshfeld surface analyses indicate that for both compounds the H⋯H contacts are the most significant, followed by O⋯H/H⋯O and C⋯H/H⋯C contacts. Full Article text
and Crystal structure and Hirshfeld surface analysis of (Z)-6-[(2-hydroxy-5-nitroanilino)methylidene]-4-methylcyclohexa-2,4-dien-1-one By scripts.iucr.org Published On :: 2019-05-17 The title compound, C14H12N2O4, is a Schiff base that exists in the keto–enamine tautomeric form and adopts a Z configuration. The molecule is almost planar, the rings making a dihedral angle of 4.99 (7)°. The molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond forming an S(6) ring motif. In the crystal, inversion-related molecules are linked by pairs of O—H⋯O hydrogen bonds, forming dimers with an R22(18) ring motif. The dimers are linked by pairs of C—H⋯O contacts with an R22(10) ring motif, forming ribbons extended along the [2overline{1}0] direction. Hirshfeld surface analysis, two-dimensional fingerprint plots and the molecular electrostatic potential surfaces were used to analyse the intermolecular interactions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯H (33.9%), O⋯H/H⋯O (29.8%) and C⋯H/H⋯C (17.3%) interactions. Full Article text
and 2-[(4-Bromophenyl)sulfanyl]-2-methoxy-1-phenylethan-1-one: crystal structure, Hirshfeld surface analysis and computational chemistry By scripts.iucr.org Published On :: 2019-05-17 The title compound, C15H13BrO2S, comprises three different substituents bound to a central (and chiral) methine-C atom, i.e. (4-bromophenyl)sulfanyl, benzaldehyde and methoxy residues: crystal symmetry generates a racemic mixture. A twist in the molecule is evident about the methine-C—C(carbonyl) bond as evidenced by the O—C—C—O torsion angle of −20.8 (7)°. The dihedral angle between the bromobenzene and phenyl rings is 43.2 (2)°, with the former disposed to lie over the oxygen atoms. The most prominent feature of the packing is the formation of helical supramolecular chains as a result of methyl- and methine-C—H⋯O(carbonyl) interactions. The chains assemble into a three-dimensional architecture without directional interactions between them. The nature of the weak points of contacts has been probed by a combination of Hirshfeld surface analysis, non-covalent interaction plots and interaction energy calculations. These point to the importance of weaker H⋯H and C—H⋯C interactions in the consolidation of the structure. Full Article text
and Crystal structure and Hirshfeld surface analysis of new polymorph of racemic 2-phenylbutyramide By scripts.iucr.org Published On :: 2019-05-21 A new polymorph of the title compound, C10H13NO, was obtained by recrystallization of the commercial product from a water/ethanol mixture (1:1 v/v). Crystals of the previously reported racemic and homochiral forms of 2-phenylbutyramide were grown from water–acetonitrile solution in 1:1 volume ratio [Khrustalev et al. (2014). Cryst. Growth Des. 14, 3360–3369]. While the previously reported racemic and enantiopure forms of the title compound adopt very similar supramolecular structures (hydrogen-bonded ribbons), the new racemic polymorph is stabilized by a single N—H⋯O hydrogen bond that links molecules into chains along the c-axis direction with an antiparallel (centrosymmetric) packing in the crystal. Hirshfeld molecular surface analysis was employed to compare the intermolecular interactions in the polymorphs of the title compound. Full Article text
and Hirshfeld surface analysis and crystal structure of N-(2-methoxyphenyl)acetamide By scripts.iucr.org Published On :: 2019-05-21 The title compound, C9H11NO2, was obtained as unexpected product from the reaction of (4-{2-benzyloxy-5-[(E)-(3-chloro-4-methylphenyl)diazenyl]benzylidene}-2-phenyloxazol-5(4H)-one) with 2-methoxyaniline in the presence of acetic acid as solvent. The amide group is not coplanar with the benzene ring, as shown by the C—N—C—O and C—N—C—C torsion angles of −2.5 (3) and 176.54 (19)°, respectively. Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the most important contributions to the crystal packing are from H⋯H (53.9%), C⋯H/H⋯C (21.4%), O⋯H/H⋯O (21.4%) and N⋯H/H⋯N (1.7%) interactions. Full Article text
and Crystal structure and Hirshfeld surface analysis of tris(2,2'-bipyridine)nickel(II) bis(1,1,3,3-tetracyano-2-ethoxypropenide) dihydrate By scripts.iucr.org Published On :: 2019-05-24 The title compound, [Ni(C10H8N2)3](C9H5N4O)2·2H2O, crystallizes as a racemic mixture in the monoclinic space group C2/c. In the crystal, the 1,1,3,3-tetracyano-2-ethoxypropenide anions and the water molecules are linked by O—H⋯N hydrogen bonds, forming chains running along the [010] direction. The bpy ligands of the cation are linked to the chain via C—H⋯π(cation) interactions involving the CH3 group. The intermolecular interactions were investigated by Hirshfeld surface analysis and two-dimensional fingerprint plots. Full Article text
and Bis[μ-bis(2,6-diisopropylphenyl) phosphato-κ2O:O']bis[(2,2'-bipyridine-κ2N,N')lithium] toluene disolvate and its catalytic activity in ring-opening polymerization of ∊-caprolactone and l-dilactide By scripts.iucr.org Published On :: 2019-05-21 The solvated centrosymmmtric title compound, [Li2(C24H34O4P)2(C10H8N2)2]·2C7H8, was formed in the reaction between {Li[(2,6-iPr2C6H3-O)2POO](MeOH)3}(MeOH) and 2,2'-bipyridine (bipy) in toluene. The structure has monoclinic (P21/n) symmetry at 120 K and the asymmetric unit consists of half a complex molecule and one molecule of toluene solvent. The diaryl phosphate ligand demonstrates a μ-κO:κO'-bridging coordination mode and the 2,2'-bipyridine ligand is chelating to the Li+ cation, generating a distorted tetrahedral LiN2O2 coordination polyhedron. The complex exhibits a unique dimeric Li2O4P2 core. One isopropyl group is disordered over two orientations in a 0.621 (4):0.379 (4) ratio. In the crystal, weak C—H⋯O and C—H⋯π interactions help to consolidate the packing. Catalytic systems based on the title complex and on the closely related complex {Li[(2,6-iPr2C6H3-O)2POO](MeOH)3}(MeOH) display activity in the ring-opening polymerization of ∊-caprolactone and l-dilactide. Full Article text
and Crystal structure of zymonic acid and a redetermination of its precursor, pyruvic acid By scripts.iucr.org Published On :: 2019-05-24 The structure of zymonic acid (systematic name: 4-hydroxy-2-methyl-5-oxo-2,5-dihydrofuran-2-carboxylic acid), C6H6O5, which had previously eluded crystallographic determination, is presented here for the first time. It forms by intramolecular condensation of parapyruvic acid, which is the product of aldol condensation of pyruvic acid. A redetermination of the crystal structure of pyruvic acid (systematic name: 2-oxopropanoic acid), C3H4O3, at low temperature (90 K) and with increased precision, is also presented [for the previous structure, see: Harata et al. (1977). Acta Cryst. B33, 210–212]. In zymonic acid, the hydroxylactone ring is close to planar (r.m.s. deviation = 0.0108 Å) and the dihedral angle between the ring and the plane formed by the bonds of the methyl and carboxylic acid carbon atoms to the ring is 88.68 (7)°. The torsion angle of the carboxylic acid group relative to the ring is 12.04 (16)°. The pyruvic acid molecule is almost planar, having a dihedral angle between the carboxylic acid and methyl-ketone groups of 3.95 (6)°. Intermolecular interactions in both crystal structures are dominated by hydrogen bonding. The common R22(8) hydrogen-bonding motif links carboxylic acid groups on adjacent molecules in both structures. In zymonic acid, this results in dimers about a crystallographic twofold of space group C2/c, which forces the carboxylic acid group to be disordered exactly 50:50, which scrambles the carbonyl and hydroxyl groups and gives an apparent equalization of the C—O bond lengths [1.2568 (16) and 1.2602 (16) Å]. The other hydrogen bonds in zymonic acid (O—H⋯O and weak C—H⋯O), link molecules across a 21-screw axis, and generate an R22(9) motif. These hydrogen-bonding interactions propagate to form extended pleated sheets in the ab plane. Stacking of these zigzag sheets along c involves only van der Waals contacts. In pyruvic acid, inversion-related molecules are linked into R22(8) dimers, with van der Waals interactions between dimers as the only other intermolecular contacts. Full Article text
and Crystal structures of butyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate and 2-methoxyethyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate By scripts.iucr.org Published On :: 2019-05-24 The title benzofuran derivatives 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate (BF1), C19H18N2O6, and 2-methoxyethyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate (BF2), C18H16N2O7, recently attracted attention because of their promising antitumoral activity. BF1 crystallizes in the space group Poverline{1}. BF2 in the space group P21/c. The nitrophenyl group is inclined to benzofuran moiety with a dihedral angle between their mean planes of 69.2 (2)° in BF1 and 60.20 (6)° in BF2. A common feature in the molecular structures of BF1 and BF2 is the intramolecular N—H⋯Ocarbonyl hydrogen bond. In the crystal of BF1, the molecules are linked head-to-tail into a one-dimensional hydrogen-bonding pattern along the a-axis direction. In BF2, pairs of head-to-tail hydrogen-bonded chains of molecules along the b-axis direction are linked by O—H⋯Omethoxy hydrogen bonds. In BF1, the butyl group is disordered over two orientations with occupancies of 0.557 (13) and 0.443 (13). Full Article text
and Crystal structure and Hirshfeld surface analysis of ethyl 2-[5-(3-chlorobenzyl)-6-oxo-3-phenyl-1,6-dihydropyridazin-1-yl]acetate By scripts.iucr.org Published On :: 2019-05-24 The title pyridazinone derivative, C21H19ClN2O3, is not planar. The unsubstituted phenyl ring and the pyridazine ring are inclined to each other, making a dihedral angle of 17.41 (13)° whereas the Cl-substituted phenyl ring is nearly orthogonal to the pyridazine ring [88.19 (13)°]. In the crystal, C—H⋯O hydrogen bonds generate dimers with R22(10) and R22(24) ring motifs which are linked by C—H⋯O interactions, forming chains extending parallel to the c-axis direction. The intermolecular interactions were investigated using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing that the most significant contributions to the crystal packing are from H⋯H (44.5%), C⋯H/H⋯C (18.5%), H⋯O/H⋯O (15.6%), Cl⋯H/H⋯Cl (10.6%) and C⋯C (2.8%) contacts. Full Article text