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The synthesis and crystal structures of the molecular salts of 4-(4-nitrophenyl) piperazine with trifluoroacetate, namely, 4-(4-nitrophenyl)piperazin-1-ium trifluoroacetate, C10H14N3O2+·C2F3O2- (I), and with trichloroacetate, namely, 4-(4-nitrophenyl)piperazin-1-ium trichloroacetate, C10H14N3O2+·C2Cl3O2-, (II), are reported and compared. A partial positional disorder of the anions was found. In both structures, the piperazine rings adopt a chair conformation, whereas the positions of the nitrophenyl group on the piperazine ring differ from bisectional in (I) to equatorial in (II). In both structures, the supramolecular assemblies are mono-periodic on the basis of the chain-of-rings motifs supported by aromatic π-π interactions. Hirshfeld surface analysis was used to explore the intermolecular close contacts in both crystals. The most dominant contacts of the Hirshfeld surface of the cation-anion pairs of the asymmetric units are O...H/H...O, and those with a contribution of halogen atoms: F...H/H...F in (I) and Cl...H/H...Cl in (II), respectively. [ABSTRACT FROM AUTHOR]

Two new 1-(thiazol-2-yl)-4,5-dihydropyrazoles have been synthesized from simple precursors, and characterized both spectroscopically and structurally. In addition, two intermediates in the reaction pathway have been isolated and characterized, one of them structurally. The molecules of the intermediate (E)- 1-(4-methoxyphenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C19H16O3 (I), are linked by a combination of C—HO and C—H(arene) hydrogen bonds to form ribbons. The products (RS)-5-(4-methoxyphenyl)-1-(4- phenythiazol-2-yl)-3-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydro-1H-pyrazole, C28H23N3O2S (II), and (RS)-5-(4-methoxyphenyl)-1-[4-(4-methylphenyl)thiazol-2- yl]-3-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydro-1H-pyrazole, C29H25N3O2S (III), are closely related – differing only by presence or absence of a methyl group at the arylthiazolyl substituent – and crystallize in an isomorphous setting. Both molecules contain an effectively planar dihydro-pyrazole ring, and possess an overall T-shaped structure, which is a characteristic of triaryl-substituted 4,5-dihydro-1-(thiazol-2-yl)pyrazole compounds. The crystal packing is characterized by intermolecular C—HS and C—H (aryl/alkyne) interactions. A combination of two C—H(arene) hydrogen bonds links the product molecules into sheets. [ABSTRACT FROM AUTHOR]

Chalcones of type 4-XC6H4C(O)CH=CHC6H4(OCH2CCH)-4, where X = Cl, Br or MeO, have been converted to the corresponding 4,5-dihydropyrazole-1-carbothioamides using a cyclocondensation reaction with thiosemicarbazide. The chalcones 1-(4-chlorophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13ClO2, (I), and 1-(4-bromophenyl)-3-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C18H13BrO2, (II), are isomorphous, and their molecules are linked into sheets by two independent C-H···π(arene) interactions, both involving the same aryl ring with one C-H donor approaching each face. In each of the products (RS)-3-(4-chlorophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16ClN3OS, (IV), (RS)-3-(4-bromophenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C19H16BrN3OS, (V), and (RS)-3-(4-methoxyphenyl)-5-[4-(prop-2-ynyloxy)phenyl]-4,5-dihydropyrazole-1-carbothioamide, C20H19N3O2S, (VI), the reduced pyrazole ring adopts an envelope conformation with the C atom bearing the 4-prop-2-ynyloxy)phenyl substituent, which occupies the axial site, displaced from the plane of the four ring atoms. Compounds (IV) and (V) are isomorphous and their molecules are linked into chains of edge-fused rings by a combination of N-H···S and C-H···S hydrogen bonds. The molecules of (VI) are linked into sheets by a combination of N-H···S, N-H···N and C-H···π(arene) hydrogen bonds. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Six new 1-aroyl-4-(4-methoxyphenyl)piperazines have been prepared, using coupling reactions between benzoic acids and N-(4-methoxyphenyl)piperazine. There are no significant hydrogen bonds in the structure of 1-benzoyl-4-(4-methoxyphenyl)piperazine, C18H20N2O2, (I). The molecules of 1-(2-fluorobenzoyl)-4-(4-methoxyphenyl)piperazine, C18H19FN2O2, (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 interaction. 1-(2-Chlorobenzoyl)-4-(4-methoxyphenyl) piperazine, C18H19ClN2O2, (III), 1-(2-bromobenzoyl)-4-(4-methoxyphenyl) piperazine, C18H19BrN2O2, (IV), and 1-(2-iodobenzoyl)-4-(4-methoxyphenyl) piperazine, C18H19IN2O2, (V), are isomorphous, but in (III) the aroyl ring is disordered over two sets of atomic sites having occupancies of 0.942 (2) and 0.058 (2). In each of (III)-(V), a combination of two C--H···π(arene) hydrogen bonds links the molecules into sheets. A single O--H···O hydrogen bond links the molecules of 1-(2-hydroxybenzoyl)-4-(4-methoxyphenyl) piperazine, C18H20N2O3, (VI), into simple chains. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

Structures are reported for eight Schiff bases derived from various salicylaldehydes: five are newly synthesized and re‐investigations are reported for three previously reported structures, leading, in each case, to some revision of previous conclusions. In (E)‐N‐(3,4‐dimethylisoxazol‐5‐yl)‐4‐[(2‐hydroxybenzylidene)amino]benzenesulfonamide, C18H17N3O4S, (I), and (E)‐4‐[(5‐bromo‐2‐hydroxy‐3‐methoxybenzylidene)amino]‐N‐(3,4‐dimethylisoxazol‐5‐yl)benzenesulfonamide. C19H18BrN3O5S, (II), the isoxazole rings adopt different orientations relative to the rest of the molecules, despite the additional substituents in (II) being in the aryl ring remote from the isoxazole unit. The molecules of both (E)‐4‐bromo‐2‐[(2‐hydroxyphenylimino)methyl]‐6‐methoxyphenol, C14H12BrNO3, (III), and (E)‐4‐bromo‐2‐methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H14BrNO3, (IV), are both effectively planar; while (III) adopts the phenol–imine constitution, (IV) adopts the keto–amine constitution. (E)‐2‐Methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H15NO3, (V), which was determined previously using powder X‐ray data assuming the phenol–imine constitution, has now been refined from single‐crystal X‐ray data, confirming the phenol–imine constitution. In (E)‐3‐benzoyl‐2‐[(5‐fluoro‐2‐hydroxybenzylidene)amino]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H18FNO2S, (VI), the fused carbocyclic ring exhibits conformational disorder; both disorder components, having populations of 0.705 (4) and 0.295 (4), adopt half‐chair conformations. The isostructural (E)‐3‐benzoyl‐2‐[(2‐hydroxybenzylidene)amino)]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H19NO2S, (VII), which was originally reported as having a fully ordered structure [Kaur et al. (2014). Acta Cryst. E70, o476–o477], has been rerefined using the original data set and found to exhibit the same type of disorder as found in (VI), with disordered populations having occupancies of 0.851 (3) and 0.149 (3). The triclinic polymorph of (E)‐[(2‐hydroxyphenylimino)methyl]phenol, C13H11NO2, (VIII), which crystallizes with Z′ = 2 in the space group P , has been described variously as occurring as the keto–amine tautomer [Maciejewska et al. (1999). J. Phys. Org. Chem.12, 875–880] and as the phenol–imine tautomer [Tunç et al. (2009). J. Chem. Crystallogr.39, 672–676]. Rerefinement of this structure using one of the original data sets shows that both of the independent molecules exist in the keto–amine form. In the structures of compounds (I), (VI), (VII) and (VIII), hydrogen bonds generate simple chains, while a chain of rings is formed in (V). Sheets are formed by hydrogen bonds in both (II) and (III), while in (IV), the sheet structure is built from aromatic π–π stacking interactions. [ABSTRACT FROM AUTHOR]

Ebastine, 4-(benzhydryloxy)-1-[4-(4-tert-butylphenyl)-4-oxobutyl]piperidine, reacts with 3,5-dinitro-benzoic acid in methanol solution to give the title 1:1 salt, ebastinium 3,5-dinitrobenzoate, C32H40NO2+⋅C7H3N2O6-. In the cation, the disubstituted aryl ring exhibits orientational disorder over two sets of atomic sites having occupancies 0.706 (4) and 0.294 (6), with a dihedral angle of 41.2 (5)° between the two orientations: the bulky Ph2CH--O-- substituent occupies an axial site on the piperidine ring. The two ions in the selected asymmetric unit are linked by a nearly linear N--H⋯O hydrogen bond and this, in combination with two C--H⋯O hydrogen bonds, links the ions into complex sheets. [ABSTRACT FROM AUTHOR]

In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C21H19F4N3O2S, (I), 1-(4-chlorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C21H19ClF3N3O2S, (II), and 1-(3-methylphenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1 H-pyrazolo[4,3- c]pyridine, C22H22F3N3O2S, (III), the reduced pyridine ring adopts a half-chair conformation with the methylsulfonyl substituent occupying an equatorial site. Although compounds (I) and (II) are not isostructural, having the space groups Pbca and P212121, respectively, their molecular conformations are very similar, but the conformation of compound (III) differs from those of (I) and (II) in the relative orientation of the N-benzyl and methylsulfonyl substituents. In compounds (II) and (III), but not in (I), the trifluoromethyl groups are disordered over two sets of atomic sites. Molecules of (I) are linked into centrosymmetric dimers by C-H...π(arene) hydrogen bonds, molecules of (II) are linked by two C-H...O hydrogen bonds to form ribbons of R33(18) rings, which are themselves further linked by a C-Cl...π(arene) interaction, and a combination of C-H...O and C-H...π(arene) hydrogen bonds links the molecules of (III) into sheets. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]

In the crystal of 2-(4-chlorophenyl)-N-(2-iodophenyl)acetamide, C14H11ClINO, molecules are linked by a combination of N-H...O and C-H...O hydrogen bonds to form a C(4)C(4)[R2 1(7)] chain of rings and chains of this type are linked by a combination of C-Cl...π(arene) and C-I...π(arene) interactions to form deeply puckered twofold interwoven sheets. In the crystal of 2-(4-chlorophenyl)-N-(pyrazin-2-yl)acetamide, C12H10ClN3O, molecules are linked into complex sheets by N-H...N, C-H...N and C-H...O hydrogen bonds, and by C-H...π(arene) interactions. [ABSTRACT FROM AUTHOR]

4-Antipyrine [4-amino-1,5-dimethyl-2-phenyl-1 H-pyrazol-3(2 H)-one] and its derivatives exhibit a range of biological activities, including analgesic, antibacterial and anti-inflammatory, and new examples are always of potential interest and value. 2-(4-Chlorophenyl)- N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1 H-pyrazol-4-yl)acetamide, C19H18ClN3O2, (I), crystallizes with Z′ = 2 in the space group P, whereas its positional isomer 2-(2-chlorophenyl)- N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1 H-pyrazol-4-yl)acetamide, (II), crystallizes with Z′ = 1 in the space group C2/ c; the molecules of (II) are disordered over two sets of atomic sites having occupancies of 0.6020 (18) and 0.3980 (18). The two independent molecules of (I) adopt different molecular conformations, as do the two disorder components in (II), where the 2-chlorophenyl substituents adopt different orientations. The molecules of (I) are linked by a combination of N-H...O and C-H...O hydrogen bonds to form centrosymmetric four-molecule aggregates, while those of (II) are linked by the same types of hydrogen bonds forming sheets. The related compound N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1 H-pyrazol-4-yl)-2-(3-methoxyphenyl)acetamide, C20H21N3O3, (III), is isomorphous with (I) but not strictly isostructural; again the two independent molecules adopt different molecular conformations, and the molecules are linked by N-H...O and C-H...O hydrogen bonds to form ribbons. Comparisons are made with some related structures, indicating that a hydrogen-bonded R22(10) ring is the common structural motif. [ABSTRACT FROM AUTHOR]

In the crystal of compound (I), C14H11ClOS, molecules are linked by C-H⋯O hydrogen bonds to form simple C(5) chains. Compound (II), C26H22O, crystallizes with Z' = 2 in space group P1; one of the molecules is fully ordered but the other is disordered over two sets of atomic sites having occupancies 0.644 (3) and 0.356 (3). The two disordered components differ from one another in the orientation of the isopropyl substituents, and both differ from the ordered molecules in the arrangement of the central propenone spacer unit, so that the crystal of (II) contains three distinct conformers. The ordered and disordered conformers each form a C(8) chain built from a single type of C-H-⋯O hydrogen bond but those formed by the disordered conformers differ from that formed by the ordered form. [ABSTRACT FROM AUTHOR]

Syntheses and structures are described for some alkylidene-substituted dihydrooxazolones and dihydroimidazoles derived from simple acylglycines. A second, triclinic, polymorph of 4-benzylidene-2-(4-methylphenyl)-1,3-oxazol-5(4 H)-one, C17H13NO2, (I), has been identified and the structure of 2-methyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4 H)-one, C9H7NO2S, (II), has been rerefined taking into account the orientational disorder of the thienyl group in each of the two independent molecules. The reactions of phenylhydrazine with 2-phenyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4 H)-one or 2-(4-methylphenyl)-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4 H)-one yield, respectively, 3-anilino-2-phenyl-5-[(thiophen-2-yl)methylidene]-3,5-dihydro-4 H-imidazol-4-one, C10H15N3OS, (III), and 3-anilino-2-(4-methylphenyl)-5-[(thiophen-2-yl)methylidene]-3,5-dihydro-4 H-imidazol-4-one, C21H17N3OS, (IV), which both exhibit orientational disorder in their thienyl groups. The reactions of 2-phenyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4 H)-one with hydrazine hydrate or with water yield, respectively, N-[3-hydrazinyl-3-oxo-1-(thiophen-2-yl)prop-1-en-2-yl]benzamide and 2-(benzoylamino)-3-(thiophen-2-yl)prop-2-enoic acid, which in turn react, respectively, with thiophene-2-carbaldehyde to form 2-phenyl-5-[(thiophen-2-yl)methylidene]-3-{[( E)-(thiophen-2-yl)methylidene]amino}-3,5-dihydro-4 H-imidazol-4-one, C19H13N3OS2, (V), which exhibits orientational disorder in only one of its thienyl groups, and with methanol to give methyl (2 Z)-2-(benzoylamino)-3-(thiophen-2-yl)prop-2-enoate, C15H13NO3S, (VI). There are no direction-specific intermolecular interactions in the crystal structure of the triclinic polymorph of (I), but the molecules of (II) are linked by two independent C-H...O hydrogen bonds to form C22(14) chains. Compounds (III) and (IV) both form centrosymmetric R22(10) dimers built from N-H...O hydrogen bonds, while compound (V) forms a centrosymmetric R22(10) dimer built from C-H...O hydrogen bonds. In the structure of compound (VI), a combination of N-H...O and C-H...π(arene) hydrogen bonds links the molecules into sheets. Comparisons are made with some similar compounds. [ABSTRACT FROM AUTHOR]

Three highly-substituted cyclohexanol derivatives have been prepared from 2-acetylpyridine and 4-halogenobenzaldehydes under mild conditions. (1 RS,2 SR,3 SR,4 RS,5 RS)-3,5-Bis(4-fluorophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol, C35H27F2N3O3, (I), (1 RS,2 SR,3 SR,4 RS,5 RS)-3,5-bis(4-chlorophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol acetone 0.951-solvate, C35H27Cl2N3O3·0.951C3H6O, (II), and (1 RS,2 SR,3 SR,4 RS,5 RS)-3,5-bis(4-bromophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol, C35H27Br2N3O3, (III), all crystallize in different space groups, viz. Pbca, Fdd2 and P, respectively. In compound (II), the acetone molecule is disordered over two sets of atomic sites having occupancies of 0.690 (13) and 0.261 (13). Each of the cyclohexanol molecules contains an intramolecular O-H...N hydrogen bond and their overall molecular conformations are fairly similar. The molecules of (I) are linked by two independent C-H...O hydrogen bonds to form a C(5) C(10)[ R22(15)] chain of rings, and those of (III) are linked by a combination of C-H...O and C-H...N hydrogen bonds, forming a chain of alternating R22(16) and R22(18) rings. The cyclohexanol molecules in (II) are linked by a single C-H...N hydrogen bond to form simple C(4) chains and these chains are linked by a π-π stacking interaction to form sheets, to which the disordered acetone molecules are weakly linked via a number of C-H...O contacts. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of the title compounds, ethyl 4-(4-hydroxyphenyl)-6-(6-methoxy-2-naphthyl)-2-oxocyclohex-3-ene-1-carboxylate (I) and ethyl 4-(3-bromophenyl)-6-(6-methoxy-2-naphthyl)-2-oxocyclohex-3-ene-1-carboxylate (II), are reported and confirmed by single crystal X-ray diffraction data. Compound (I), C26H24O5, crystallizes from a methanol solution in the monoclinic C2/c space group with eight molecules in the unit cell. The unit cell parameters are: a = 25.4114(5) Å, b = 8.47440(10) Å, c = 20.6921(4) Å, ß = 108.328(2)° and V = 4229.92(13) ų. Disorder is observed throughout the entire molecule with an occupancy ratio 0.690(2):0.310(2). Compound (II), C26H23O4Br, crystallizes from an ethyl acetate solution in the monoclinic P21/c spacegroup with four molecules in the unit cell. The unit cell parameters are α = 17.8991(9) Å, b = 11.4369(6) Å, c = 10.8507(5) Å, β = 92.428(4)° and V = 2219.25(19) ų. Disorder is observed in the cyclohexenone ring and the carboxylate group with an occupancy ratio 0.830(6):0.170(6). Weak O--H⋯O (I) or C--H⋯O (II) intermolecular interactions are observed which influence crystal packing stability. These chalcone derivative types of molecules are important in their ability to act as activated unsaturated systems in conjugated addition reactions of carbanions in the presence of basic catalysts which exhibit a multitude of biological activities. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of two 2-aminothiophene derivatives, potential allosteric enhancers at the human A1 adenosine receptor, are reported. (2-Amino-4,5,6,7-tetrahydro-1-benzothiophen-3-yl)(phenyl)methanone (1) crystallizes in the orthorhombic space group Pna21 (a = 9.2080(4) Å, b = 14.0485(7) Å, c = 10.3826(6) Å), and (2-amino-5-ethylthiophen-3-yl)(2-chlorophenyl)methanone (2) crystalizes in the monoclinic P21/c space group with unit cell parameters a = 10.6092(8) Å, b = 10.8355(8) Å, c = 11.1346(9) Å, β = 98.643(6)Å. In both molecules the intramolecular N--H⋯O=C hydrogen bonds close six-membered planar rings and significantly influence the molecular conformation. Intermolecular N--H⋯O bonds connect the molecules in infinite chains along a in case of 1, and along b in 2; in each case the appropriate unit cell axis is approximately 10 Å long. [ABSTRACT FROM AUTHOR]

The structure of the title compound, C15H13NO, has six independent mol­ecules in the asymmetric unit; in each case, the seven-membered ring adopts a boat conformation and the overall molecular shape is that of a butterfly. All mol­ecules display N—H⋯C=C close contacts, instead of N—H⋯O interactions. The intramolecular dihedral angles between the benzene rings are within the range 43.7 (1)–46.4 (1)° for the six mol­ecules. [ABSTRACT FROM AUTHOR]

The structure of the title compound, C6H13ClNO+·Cl−, comprises a cation with the morpholine ring in the chair conformation, and a single hydrogen-bonding association between the morpholinium NH group and the Cl− anion. [ABSTRACT FROM AUTHOR]

Molecules of the title compound, C9H15NO3, form a two-dimensional hydrogen-bonded network, via O—H·O and N—H·O interactions, which runs parallel to the bc plane. In this structure, neither the carboxyl­ic acid groups nor the carbamoyl groups are involved in dimer formations. [ABSTRACT FROM AUTHOR]

The title compound, C10H8N2O4S, serves as a starting material for the synthesis of antihyperglycemic pharmaceuticals. The nearly planar thia­zolidine-2,4-dione ring is almost perpendic­ular to the nitro­phenyl ring. [ABSTRACT FROM AUTHOR]

The title compound, C9H13NO, is the key intermediate for the synthesis of the antidiabetic drug pioglitazone and it is used as a versatile intermediate in the synthesis of a number of biologically active novel heterocycles. Both side-chains are located on the same side of the aromatic ring. The mol­ecules are connected by O—H⋯N hydrogen bonds into ribbons which show a herring-bone-like pattern. [ABSTRACT FROM AUTHOR]