Syntheses, crystal structures and Hirshfeld surface analysis of three salts of 1-(4-nitro-phenyl)-piperazine.

The structures and Hirshfeld surface analysis of three salts of 1-(4-nitro-phenyl)-piperazine are discussed. In 4-(4-nitro-phen-yl)piperazin-1-ium salicylate (CHNO ·CHO ), there are strong hydrogen bonds between cation and anion and the 4-nitro-phenyl substituent occupies an equatorial position in the piperazinium ring. The cation and anion are linked together by supra-molecular inter-actions [graph-set notation of hydrogen bonding (6) propagating in the -axis direction].

Isopropyl 4-amino-benzoate.

The title compound, CHNO, crystallizes with two mol-ecules ( and ) in the asymmetric unit. For , the dihedral angle between the plane of the phenyl ring and the -propyl substituent is 65.4 (3)° while for this angle is 67.

The structures of eleven (4-phen-yl)piperazinium salts containing organic anions.

Eleven (4-phen-yl)piperazinium salts containing organic anions have been prepared and structurally characterized, namely, 4-phenyl-piperazin-1-ium 4-fluoro-benzoate monohydrate, CHN ·CHFO ·HO, ; 4-phenyl-piperazin-1-ium 4-bromo-benzoate monohydrate, CHN ·CHBrO ·HO, ; 4-phenyl-piperazin-1-ium 4-iodo-benzoate, CHN ·CHIO , ; 4-phenyl-piperazin-1-ium 4-nitro-benzoate, CHN ·CHNO , ; 4-phenyl-piperazin-1-ium 3,5-di-nitro-salicylate, CHN ·CHNO , ; 4-phenyl-piperazin-1-ium 3,5-di-nitro-benzoate, CHN ·CHNO , ; 4-phenyl-piperazin-1-ium picrate, CHN ·CHNO , ; 4-phenyl-piperazin-1-ium benzoate monohydrate, CHN ·CHO ·HO, ; 4-phenyl-piperazin-1-ium -toluene-sulfonate, CHN ·CHOS, ; 4-phenyl-piperazin-1-ium tartarate monohydrate, CHN ·CHO ·HO, ; and 4-phenyl-piperazin-1-ium fumarate, CHN ·CHO , . Compounds and - are all 1:1 salts with the acid proton transferred to the phenyl-piperaizine basic N atom (the secondary amine) with the exception of where there is disorder in the proton position with it being 68% attached to the base and 32% attached to the acid. Of the structures with similar stoichiometries only and are isomorphous.

Synthesis and crystal structures of 1-benzoyl-4-(4-nitro-phen-yl)piperazine and 1-(4-bromo-benzo-yl)-4-phenyl-piperazine at 90 K.

Synthesis and crystal structures of 1-benzoyl-4-(4-nitro-phen-yl)piperazine, CHNO, () and 1-(4-bromo-benzo-yl)-4-phenyl-piperazine, CHBrNO, () are described. Compounds and crystallize in the ortho-rhom-bic and monoclinic crystal systems with space groups 2 (' = 2, ) and 2 (' = 1, ), respectively. The crystal of was a two-component aggregate, treated as a 'twin' for data-acquisition purposes.

Synthesis and crystal structure of topiramate azido-sulfate at 90 K and 298 K.

The low (90 K) and room (298 K) temperature crystal structures of topiramate azido-sulfate [systematic name 2,3:4,5-bis--(1-methyl-ethyl-idene)-β-d-fructo-pyran-ose azido-sulfate], CHNOS, an inter-mediate in the synthesis of the anti-convulsant drug topiramate, are described. Topiramate azido-sulfate () finds use as a reference impurity standard for topiramate. A modified synthesis and some spectroscopic details are also presented.

Synthesis and crystal structure of ebastinium hydrogen fumarate.

The structure of ebastinium hydrogen fumarate {systematic name: 1-[4-(4--butyl-phen-yl)-4-oxobut-yl]-4-(di-phenyl-meth-oxy)piperidin-1-ium ()-3-carb-oxy-1-hy-droxy-prop-2-en-1-olate}, CHNO ·CHO , a 1:1 salt formed in the reaction between ebastine and fumaric acid is presented. All examined crystals were found to be twinned by pseudo-merohedry. The structure is extensively disordered, with over half (20 out of 35) its non-hydrogen atoms modelled as lying over two sets of sites.

Crystal-structure studies of 4-phenyl-piperazin-1-ium 4-eth-oxy-benzoate monohydrate, 4-phenyl-piperazin-1-ium 4-meth-oxy-benzoate monohydrate, 4-phenyl-piperazin-1-ium 4-methyl-benzoate monohydrate and 4-phenyl-piperazin-1-ium tri-fluoro-acetate 0.12-hydrate.

In this study, four new piperazinium salts, namely, 4-phenyl-piperazin-1-ium 4-eth-oxy-benzoate monohydrate, CHO·CHN·HO (); 4-phenyl-piperazin-1-ium 4-meth-oxy-benzoate monohydrate, CHN·CHO·HO (); 4-phenyl-piperazin-1-ium 4-methyl-benzoate monohydrate, CHN·CHO·HO (); and 4-phenyl-piperazin-1-ium tri-fluoro-acetate 0.12 hydrate, CHN·CFO·0.12HO (), have been synthesized.

Crystal structures of six 4-(4-nitro-phenyl)-piperazin-1-ium salts.

Six piperazinium salts, namely 4-(4-nitro-phenyl)-piperazin-1-ium 4-bromo-ben-zo-ate dihydrate, CHNO ·CHBrO ·2HO, (I), 4-(4-nitro-phenyl)-pi-per-a-zin-1-ium 4-iodo-benzoate dihydrate, CHNO ·CHIO ·2HO, (II), 4-(4-nitro-phenyl)-piperazin-1-ium 4-hy-droxy-benzoate monohydrate, CHNO ·CHO ·HO, (III), 4-(4-nitro-phenyl)-piperazin-1-ium 4-methyl-benzoate monohydrate, CHNO ·CHO ·HO, (IV), 4-(4-nitro-phenyl)-piperazin-1-ium 4-meth-oxy-benzoate hemihydrate, 2CHNO ·2CHO ·HO, (V), and 4-(4-nitro-phenyl)-piperazin-1-ium 4-eth-oxy-benzoate, 2CHNO ·2CHO , (VI), have been synthesized and their crystal structures solved by single-crystal X-ray diffraction, revealing that all of them crystallize in the triclinic space group except for (V), which crystallizes in the monoclinic space group 2/ and has a disordered nitro group. Compounds (I) and (II) are isostructural. The crystal packing of (I)-(V) is constructed from organic chains formed by a combination of hydrogen bonds of type N-H⋯O and/or O-H⋯O and other weak inter-actions of type C-H⋯O and/or C-H⋯π, forming sheets, whereas (VI) shows a cationic and anionic-based layer structure.

Crystal structure studies of 4-ethyl-piperazin-1-ium 3,5-di-nitro-benzoate, 4-methyl-piperazin-1-ium 3,5-di-nitro-benzoate and 4-methyl-piperazin-1-ium 4-iodo-benzoate.

As part of our ongoing investigation on the chemical and biological properties of piperazinium salts, we synthesized three novel compounds: 1-ethyl-piperazinium 3,5-di-nitro-benzoate (I), 1-methyl-piperazinium 3,5-di-nitro-benzoate (II) and 1-methyl-piperazinium 4-iodo-benzoate (III). The crystal structures of these compounds are built up of organic layers formed by the strong connection between the mol-ecules by hydrogen bonds of type N-H⋯O. These layers are linked through N-H⋯O hydrogen bonds and C-H⋯O inter-actions or C-I⋯N halogen bonding, leading to the formation of a three-dimensional network.

Functionalized 3-(5-ar-yloxy-3-methyl-1-phenyl-1-pyrazol-4-yl)-1-(4-substituted-phen-yl)prop-2-en-1-ones: synthetic pathway, and the structures of six examples.

Five examples each of 3-(5-ar-yloxy-3-methyl-1-phenyl-1-pyrazol-4-yl)-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-ones and the corresponding 1-(4-azido-phen-yl)-3-(5-ar-yloxy-3-methyl-1-phenyl-1-pyrazol-4-yl)prop-2-en-1-ones have been synthesized in a highly efficient manner, starting from a common source precursor, and structures have been determined for three examples of each type. In each of 3-[5-(2-chloro-phen-oxy)-3-methyl-1-phenyl-1-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-one, CHClNO, (Ib), the isomeric 3-[5-(2-chloro-phen-oxy)-3-methyl-1-phenyl-1-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yl-oxy)phen-yl]prop-2-en-1-one, (Ic), and 3-[3-methyl-5-(naphthalen-2-yl-oxy)-1-phenyl-1-pyrazol-4-yl]-1-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, CHNO, (Ie), the mol-ecules are linked into chains of rings, formed by two independent C-H⋯O hydrogen bonds in (Ib) and by a combination of C-H⋯O and C-H⋯π(arene) hydrogen bonds in each of (Ic) and (Ie). There are no direction-specific inter-molecular inter-actions in the structure of 1-(4-azido-phen-yl)-3-[3-methyl-5-(2-methyl-phen-oxy)-1-phenyl-1-pyrazol-4-yl]prop-2-en-1-one, CHNO, (IIa).

Crystal structures of the recreational drug -(4-meth-oxy-phen-yl)piperazine (MeOPP) and three of its salts.

Crystal structures are reported for -(4-meth-oxy-phen-yl)piperazine (MeOPP), (I), and for its 3,5-di-nitro-benzoate, 2,4,6-tri-nitro-phenolate (picrate) and 4-amino-benzoate salts, (II)-(IV), the last of which crystallizes as a monohydrate. In MeOPP, CHNO, (I), the 4-meth-oxy-phenyl group is nearly planar and it occupies an equatorial site on the piperazine ring: the mol-ecules are linked into simple (10) chains by N-H⋯O hydrogen bonds. In each of the salts, , CHNO·CHNO , (II), CHNO·CHNO , (III), and CHNO·CHNO ·HO, (IV), the effectively planar 4-meth-oxy-phenyl substituent again occupies an equatorial site on the piperazine ring.

Crystal structures of three 6-aryl-2-(4-chloro-benz-yl)-5-[(1-indol-3-yl)meth-yl]imidazo[2,1-][1,3,4]thia-diazo-les.

Three title compounds, namely, 2-(4-chloro-benz-yl)-5-[(1-indol-3-yl)meth-yl]-6-phenyl-imidazo[2,1-][1,3,4]thia-diazole, CHClNS, (I), 2-(4-chloro-benz-yl)-6-(4-fluoro-phen-yl)-5-[(1-indol-3-yl)meth-yl]imidazo[2,1-][1,3,4]thia-diazole, CHClFNS, (II), and 6-(4-bromo-phen-yl)-2-(4-chloro-benz-yl)-5-[(1-indol-3-yl)meth-yl]imidazo[2,1-][1,3,4]thia-diazole, CHBrClNS, (III), have been prepared using a reductive condensation of indole with the corresponding 6-aryl-2-(4-chloro-benz-yl)imidazo[2,1-][1,3,4]thia-diazole-5-carbaldehydes (aryl = phenyl, 4-fluoro-phenyl or 4-bromo-phen-yl), and their crystal structures have been determined. The asymmetric unit of compound (I) consists of two independent mol-ecules and one of the mol-ecules exhibits disorder of the 4-chloro-benzyl substituent with occupancies 0.6289 (17) and 0.

Twelve 4-(4-meth-oxy-phen-yl)piperazin-1-ium salts containing organic anions: supra-molecular assembly in one, two and three dimensions.

Twelve 4-(4-meth-oxy-phen-yl)piperazin-1-ium salts containing organic anions have been prepared and structurally characterized. The monohydrated benzoate, 4-fluoro-benzoate, 4-chloro-benzoate and 4-bromo-benzoate salts, CHNO·CHO ·HO (I), CHNO·CHFO ·HO (II), CHNO·CHClO ·HO (III), and CHNO·CHBrO ·HO (IV), respectively, are isomorphous and all exhibit disorder in the 4-meth-oxy-phenyl unit: the components are linked by N-H⋯O and O-H⋯O hydrogen bond to form chains of rings. The unsolvated 2-hy-droxy-benzoate, pyridine-3-carboxyl-ate and 2-hy-droxy-3,5-di-nitro-benzoate salts, CHNO·CHO (V), CHNO·CHNO (VI) and CHNO·CHNO (VII), respectively, are all fully ordered: the components of (V) are linked by multiple N-H⋯O hydrogen bonds to form a chain of rings; those of (VI) are linked into a three-dimensional framework by a combination of N-H⋯O, C-H⋯O and C-H⋯N hydrogen bonds and those of (VII), where the anion has a structure reminiscent of the picrate anion, are linked into a three-dimensional array by N-H⋯O and C-H⋯O hydrogen bonds.

Six 1-aroyl-4-(4-meth-oxy-phen-yl)piperazines: similar mol-ecular structures but different patterns of supra-molecular assembly.

Six new 1-aroyl-4-(4-meth-oxy-phen-yl)piperazines have been prepared, using coupling reactions between benzoic acids and -(4-meth-oxy-phen-yl)piperazine. There are no significant hydrogen bonds in the structure of 1-benzoyl-4-(4-meth-oxy-phen-yl)piperazine, CHNO, (I). The mol-ecules of 1-(2-fluoro-benzo-yl)-4-(4-meth-oxy-phen-yl)piperazine, CHFNO, (II), are linked by two C-H⋯O hydrogen bonds to form chains of rings, which are linked into sheets by an aromatic π-π stacking inter-action.

Conversion of substituted 5-aryloxypyrazolecarbaldehydes into reduced 3,4'-bipyrazoles: synthesis and characterization, and the structures of four precursors and two products, and their supramolecular assembly in zero, one and two dimensions.

The reaction of 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde with phenols under basic conditions yields the corresponding 5-aryloxy derivatives; the subsequent reaction of these carbaldehydes with substituted acetophenones yields the corresponding chalcones, which in turn undergo cyclocondensation reactions with hydrazine in the presence of acetic acid to form N-acetylated reduced bipyrazoles. Structures are reported for three 5-aryloxycarbaldehydes and the 5-piperidino analogue, and for two reduced bipyrazole products. 5-(2-Chlorophenoxy)-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde, CHClNO, (II), which crystallizes with Z' = 2 in the space group P-1, exhibits orientational disorder of the carbaldehyde group in each of the two independent molecules.