0000000000398096

AUTHOR

Mikelis V. Veidis

Bis(N,N′-diphenylbenzamidinium) fumarate

The crystal structure of the title compound, 2C(19)H(17)N(2) (+)·C(4)H(2)O(4) (2-), consists of centrosymmetric trimers built up of two crystallographically independent N,N'-diphenyl-benzamid-in-ium cations and one fumarate dianion, which is located on a centre of inversion. The components of the trimers are linked by N-H⋯O hydrogen bonding. In the cation, the outer rings make dihedral angles of 53.66 (5) and 78.38 (5)° with the central ring. The two outer rings make a dihdral angle of 81.49 (5)°.

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Dipotassium 4,4′-(hexane-3,4-diyl)bis(benzenesulfonate) dihydrate

The anion of the title compound, also called sygethin dihydrate, 2K+·C18H20O6S22−·2H2O, has crystallographic inversion symmetry. The K+ cation is surrounded by eight O atoms in a distorted cubic coordination geometry, forming extended K—O—S networks. There are also O—H...O hydrogen bonds.

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Conformation of the umifenovir cation in the molecular and crystal structures of four carboxylic acid salts

The umifenovir salts of maleic, salicylic, glutaric, and gentisic acid as well as the chloroform solvate of the salicylate were prepared. Single crystals of the five compounds were obtained and their molecular and crystal structures determined by X-ray diffraction. In each structure the conformation of phenyl ring with respect to the indole group of the umifenovir moiety is different. The water solubility and melting points of the studied umifenovir salts have been determined.

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Bis(N,N′-diphenylbenzamidinium) fumarate

The crystal structure of the title compound, 2C19H17N2+·C4H2O42−, consists of centrosymmetric trimers built up of two crystallographically independent N,N′-diphenylbenzamidinium cations and one fumarate dianion, which is located on a centre of inversion. The components of the trimers are linked by N—H...O hydrogen bonding. In the cation, the outer rings make dihedral angles of 53.66 (5) and 78.38 (5)° with the central ring. The two outer rings make a dihdral angle of 81.49 (5)°.

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Crystal and Molecular Structure and Stability of Isoniazid Cocrystals with Selected Carboxylic Acids

Reaction of isoniazid with benzoic acid, sebacic acid, suberic acid, and cinnamic acid results in formation of cocrystals. Two polymorphs of isoniazid–suberic acid and two polymorphs of isoniazid–cinnamic acid cocrystals were isolated. Crystal structure analysis shows the presence of a pyridine–carboxylic acid synthon in the studied cocrystals. The hydrazide group of isoniazid participates in N–H···O and N–H···N hydrogen bond formation, producing different supramolecular synthons. The stability study of isoniazid cocrystals has been performed over a 22 week period. A comparison of melting points of isoniazid–dicarboxylic acid 2:1 cocrystals shows the decrease of melting point with an increa…

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The effect of pH on polymorph formation of the pharmaceutically active compound tianeptine.

The anti-depressant pharmaceutical tianeptine has been investigated to determine the dynamics of polymorph formation under various pH conditions. By varying the pH two crystalline polymorphs were isolated. The molecular and crystal structures have been determined to identify the two polymorphs. One polymorph is an amino carboxylic acid and the other polymorph is a zwitterion. In the solid state the tianeptine moieties are bonded through hydrogen bonds. The zwitterion was found to be less stable and transformed to the acid form. During this investigation an amorphous form was identified.

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Dipotassium 4,4'-(hexane-3,4-di-yl)bis-(benzene-sulfonate) dihydrate.

The anion of the title compound, also called sygethin dihydrate, 2K(+)·C(18)H(20)O(6)S(2) (2-)·2H(2)O, has crystallographic inversion symmetry. The K(+) cation is surrounded by eight O atoms in a distorted cubic coordination geometry, forming extended K-O-S networks. There are also O-H⋯O hydrogen bonds.

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Spontaneous cocrystal hydrate formation in the solid state: crystal structure aspects and kinetics

Kinetics of anhydrous cocrystal hydration and that of cocrystal monohydrate formation from starting compounds in the solid state are studied as a function of RH and time. The propensity of the anhydrate to hydration is related to the crystal structures of anhydrous and hydrated forms.

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Nicotinamide fumaric acid supramolecular cocrystals: diversity of stoichiometry

Synthesis of nicotinamide and fumaric acid supramolecular cocrystals with 1 : 1 and 2 : 1 amide to acid stoichiometries results in the formation of an amide–acid heterosynthon (1 : 1 stoichiometry) and an amide–amide homosynthon (2 : 1 stoichiometry) and different conformations of the fumaric acid moieties.

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The conformation of pyrogallol as a result of cocrystallization with N-heterocyclic bases

Structural analysis of the supramolecular cocrystals formed by pyrogallol with acridine, 4,4′-bipyridine, and 1,10-phenanthroline shows that the studied cocrystals are assembled via the hydroxyl–pyridine heterosynthon. In the crystal and molecular structures of these cocrystals in order to form the maximum number of hydrogen bonds, taking into consideration steric effects, the pyrogallol moiety in the supramolecular arrangement has the following conformations: with acridine - syn1, 4,4′-bipyridine - anti, and 1,10-phenanthroline - syn2. Discrete supramolecular complexes are formed by acridine–pyrogallol and the 1,10-phenanthroline–pyrogallol polymorph I. The 1,10-phenanthroline–pyrogallol p…

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N-(2,6-Dimethylanilino)-5,6-dihydro-4H-1,3-thiazin-3-ium chloride monohydrate

In the title compound, alternatively called xylazine hydro-chloride monohydrate, C(12)H(17)N(2)S(+)·Cl(-)·H(2)O, the six-membered thia-zine ring is in a half-chair conformation. In the crystal structure, six component centrosymmetric clusters are formed via inter-molecular O-H⋯Cl, N-H⋯O and N-H⋯Cl hydrogen bonds involving xylazine cations, chloride anions and water mol-ecules.

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CCDC 931509: Experimental Crystal Structure Determination

Related Article: Liana Orola, Inese Sarcevica, Artis Kons, Andris Actins, Mikelis V. Veidis|2014|J.Mol.Struct.|1056|63|doi:10.1016/j.molstruc.2013.10.010

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CCDC 931507: Experimental Crystal Structure Determination

Related Article: Liana Orola, Inese Sarcevica, Artis Kons, Andris Actins, Mikelis V. Veidis|2014|J.Mol.Struct.|1056|63|doi:10.1016/j.molstruc.2013.10.010

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CCDC 931511: Experimental Crystal Structure Determination

Related Article: Liana Orola, Inese Sarcevica, Artis Kons, Andris Actins, Mikelis V. Veidis|2014|J.Mol.Struct.|1056|63|doi:10.1016/j.molstruc.2013.10.010

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CCDC 890182: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Mikelis V.Veidis, Anton Podjava, and Sergey Belyakov|2013|Cryst.Growth Des.|13|1082|doi:10.1021/cg301356h

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CCDC 931510: Experimental Crystal Structure Determination

Related Article: Liana Orola, Inese Sarcevica, Artis Kons, Andris Actins, Mikelis V. Veidis|2014|J.Mol.Struct.|1056|63|doi:10.1016/j.molstruc.2013.10.010

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CCDC 890184: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Mikelis V.Veidis, Anton Podjava, and Sergey Belyakov|2013|Cryst.Growth Des.|13|1082|doi:10.1021/cg301356h

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CCDC 890181: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Mikelis V.Veidis, Anton Podjava, and Sergey Belyakov|2013|Cryst.Growth Des.|13|1082|doi:10.1021/cg301356h

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CCDC 890180: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Mikelis V.Veidis, Anton Podjava, and Sergey Belyakov|2013|Cryst.Growth Des.|13|1082|doi:10.1021/cg301356h

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CCDC 890183: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Mikelis V.Veidis, Anton Podjava, and Sergey Belyakov|2013|Cryst.Growth Des.|13|1082|doi:10.1021/cg301356h

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CCDC 933429: Experimental Crystal Structure Determination

Related Article: Inese Sarcevica, Liana Orola, Sergey Belyakov, Mikelis V. Veidis|2013|New J.Chem.|37|2978|doi:10.1039/C3NJ00489A

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CCDC 931508: Experimental Crystal Structure Determination

Related Article: Liana Orola, Inese Sarcevica, Artis Kons, Andris Actins, Mikelis V. Veidis|2014|J.Mol.Struct.|1056|63|doi:10.1016/j.molstruc.2013.10.010

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