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Search Results: 1 - 10 of 31011 matches for " Thomas Gelbrich "
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Butallylonal 1,4-dioxane hemisolvate
Thomas Gelbrich,Denise Rossi,Ulrich J. Griesser
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810038651
Abstract: The asymmetric unit of the title compound [systematic name: 5-(1-bromoprop-2-en-1-yl)-5-sec-butylpyrimidine-2,4,6-trione 1,4-dioxane hemisolvate], C11H15BrN2O3·0.5C4H8O2, contains one half-molecule of 1,4-dioxane and one molecule of butallylonal, with an almost planar barbiturate ring [largest deviation from the mean plane = 0.049 (5) ]. The centrosymmetric dioxane molecule adopts a nearly ideal chair conformation. The barbiturate molecules are linked together by an N—H...O hydrogen bond, giving a single-stranded chain. Additionally, each dioxane molecule acts as a bridge between two antiparallel strands of hydrogen-bonded barbiturate molecules via two hydrogen bonds, N—H...O(dioxane)O...H—N. Thus, a ladder structure is obtained, with the connected barbiturate molecules forming the `stiles' and the bridging dioxane molecules the `rungs'.
5,5-Dihydroxybarbituric acid 1,4-dioxane hemisolvate
Thomas Gelbrich,Denise Rossi,Ulrich J. Griesser
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810015321
Abstract: The asymmetric unit of the title compound,, C4H4N2O5·0.5C4H8O2, contains one molecule of 5,5-dihydroxybarbituric acid with a nearly planar barbiturate ring and half a molecule of 1,4-dioxane. The geometry of the centrosymmetric dioxane molecule is close to an ideal chair conformation. The crystal structure exhibits a complex three-dimensional hydrogen-bonded network. Barbiturate molecules are connected to one another via N—H...O=C, O—H...O=C and N—H...O(hydroxy) interactions, while the barbituric acid molecule is linked to dioxane by an O—H...O contact.
Tetragonal polymorph of 5,5-dichlorobarbituric acid
Thomas Gelbrich,Denise Rossi,Ulrich J. Griesser
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536811054626
Abstract: The tetragonal polymorph of 5,5-dichlorobarbituric acid (m.p. 478 K), C4H2Cl2N2O3, forms an N—H...O hydrogen-bonded tape structure along [001]. Two tapes related by a twofold rotation axis are associated via Cl...O contacts [3.201 (1) ], and four such chain pairs are arranged around a fourfold roto-inversion axis. The crystal structures of the monoclinic and orthorhombic polymorphs have been reported previously [Gelbrich et al. (2011). CrystEngComm, 13, 5502–5509].
Thomas Gelbrich,Mairi F. Haddow,Ulrich J. Griesser
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810022105
Abstract: The crystal structure of the title compound, C11H13ClF3N3O4S3 (systematic name: 6-chloro-2-methyl-3-{[(2,2,2-trifluoroethyl)sulfanyl]methyl}-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide; CRN: 346–18–9), exhibits a two-dimensional network of hydrogen-bonded molecules parallel to (overline{1}01). The NH and NH2 groups act as donor sites and the sulfonyl O atoms as acceptor sites in N—H...O hydrogen bonds, and a C—H...O interaction also occurs. The thiadiazine ring adopts an envelope conformation with the N atom bonded to sulfur at the tip of the flap, and the methyl substituent is in an axial position.
Morphine hydrochloride anhydrateCAS number: 52–26–6.
Thomas Gelbrich,Doris E. Braun,Ulrich J. Griesser
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812046405
Abstract: In the title molecular salt [systematic name: (5α,6α)-7,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol hydrochloride], C17H20NO3+·Cl , the conformation of the morphinium ion is in agreement with the characteristics of the previously reported morphine forms [for example, Gylbert (1973). Acta Cryst. B29, 1630–1635]. In the crystal, the cations and chloride anions are linked into a helical chain propagating parallel to the b-axis direction by N—H...Cl and O—H...Cl hydrogen bonds. The title salt and the morphine monohydrate [Bye (1976) Acta Chem. Scand. 30, 549–554] display very similar one-dimensional packing modes of their morphine components.
Stable polymorph of morphineCAS number: 57–27–2.
Thomas Gelbrich,Doris E. Braun,Ulrich J. Griesser
Acta Crystallographica Section E , 2013, DOI: 10.1107/s1600536812048945
Abstract: In the stable polymorph of the title compound, C17H19NO3 [systematic name: (5α,6α)-7,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol], the molecular conformation is in agreement with the characteristics of previously reported morphine forms. The molecule displays the typical T-shape and its piperidine ring adopts a slightly distorted chair conformation. Intermolecular O—H...O hydrogen bonds link the molecules into helical chains parallel to the b axis. Intramolecular O—H...O hydrogen bonds are also observed.
Thomas Gelbrich,Mairi F. Haddow,Ulrich J. Griesser
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811019490
Abstract: The crystal of the title compound [systematic name: 4-(benzylamino)benzenesulfonamide], C13H14N2O2S, displays a hydrogen-bonded framework structure. Molecules are doubly N—H...O hydrogen bonded to one another via their NH2 groups and sulfonyl O atoms. These interactions generate a hydrogen-bonded ladder structure parallel to the a axis, which contains fused R22(8) rings. The NH group serves as the hydrogen-bond donor for a second set of intermolecular N—H...O=S interactions.
Thomas Gelbrich,Mairi F. Haddow,Ulrich J. Griesser
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811016680
Abstract: The title compound {systematic name: N-cyclohexylcarbamoyl-4-[2-(7-methoxy-4,4-dimethyl-1,3-dioxo-1,2,3,4-tetrahydroisoquinolin-2-yl)ethyl]benzenesulfonamide}, C27H33N3O6S, displays an intramolecular N—H...O=S interaction, as well as intermolecular N—H...O=C hydrogen bonds. The latter interactions lead to the formation of hydrogen-bonded chains parallel to the c axis. The conformation of the sulfonylurea fragment is in agreement with a recent theoretical study [Kasetti et al. (2010). J. Phys. Chem. B, 114, 11603–11610].
Polymorphic form II of 4,4′-methylenebis(benzenesulfonamide)
Thomas Gelbrich,Mairi F. Haddow,Ulrich J. Griesser
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810021409
Abstract: In the title compound, C13H14N2O4S2 (alternative names: diphenylmethane-4,4′-disulfonamide, nirexon, CRN: 535–66-0), the two benzene rings form a dihedral angle of 70.8 (1)°. There are two sets of shorter (H...O < 2.1 ) and longer (H...O > 2.4 ) N—H...O hydrogen bonds per sulfonamide NH2 group, which together result in hydrogen-bonded sheets parallel (102). Adjacent sheets are connected to one another by an additional N—H...N interaction so that a three-dimensional network of hydrogen-bonded molecules is formed. The investigated polymorph is identical with the form II previously described by Kuhnert-Brandst tter & Moser [(1981). Mikrochim. Acta, 75, 421–440].
An Alkali Activated Binder for High Chemical Resistant Self-Leveling Mortar  [PDF]
Henrik L. Funke, Sandra Gelbrich, Lothar Kroll
Open Journal of Composite Materials (OJCM) , 2016, DOI: 10.4236/ojcm.2016.64013
Abstract: This paper reports the development of an Alkali Activated Binder (AAB) with an emphasis on the performance and the durability of the AAB-matrix. For the development of the matrix, the reactive components granulated slag and coal fly ash were used, which were alkali activated with a mixture of sodium hydroxide (2 - 10 mol/l) and aqueous sodium silicate solution (SiO2/Na2O molar ratio: 2.1) at ambient temperature. A sodium hydroxide concentration of 5.5 mol/l revealed the best compromise between setting time and mechanical strengths of the AAB. With this sodium hydroxide concentration, the compressive and the 3-point bending tensile strength of the hardened AAB were 53.4 and 5.5 MPa respectively after 14 days. As a result of the investigation of the acid resistance, the AAB-matrix showed a very high acid resistance in comparison to ordinary Portland cement concrete. In addition, the AAB had a high frost resistance, which had been validated by the capillary suction, internal damage and freeze thaw test with a relative dynamic E-Modulus of 93% and a total amount of scaled material of 30 g/m2 after 28 freeze-thaw cycles (exposure class: XF3).
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