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This study presents the synthesis, crystal structure, and a Hirshfeld-surface analysis of the bioactive compound 5-methyl-1H-pyrazol-3-yl 4-nitro­benzene­sulfonate­(C10H9N3O5S), a pyrazole derivative with pharmacological potential. Pyrazoles are known for diverse bioactivities, and recent research emphasizes their role as a ‘privileged structure’ in drug design. Here, the asymmetric unit of the title compound contains two distinct mol­ecules, A and B, exhibiting differences in conformation resulting from variation in key torsion angles. These distinctions influence the mol­ecular orientation and inter­molecular inter­actions, with strong N—H⋯N and N—H⋯O hydrogen bonds forming a centrosymmetric tetra­mer stabilized by π–π stacking. Hirshfeld surface analysis readily confirms differing inter­molecular contacts for A and B, primarily involving hydrogen atoms and differences in their close contacts to nitro­gen and oxygen. This study offers further insight into the mol­ecular architecture and potential inter­actions of pyrazole-based drug candidates. [ABSTRACT FROM AUTHOR]

The etoxazole metabolite R13, systematic name 4-(4-tert-butyl-2-eth­oxy­phen­yl)-2-(2,6-di­fluoro­phen­yl)oxazole (C21H21F2NO2), results from the oxidation of etoxazole, a chitin synthesis inhibitor belonging to the oxazoline class, widely used as an insecticide/acaricide since 1998. The structure of R13 features a central oxazole ring with attached 2,6-di­fluoro­phenyl and 4-t-butyl-2-eth­oxy­phenyl moieties. The overall conformation gives dihedral angles between these rings and the oxazole of 24.91 (5)° (with di­fluoro­phen­yl) and 15.30 (6)° (with t-butyl-eth­oxy­phen­yl), indicating an overall deviation from planarity. Additionally, torsion angles of the eth­oxy and t-butyl groups define the orientation of these substituents relative to their benzene ring. In the crystal packing, no significant hydrogen bonds are present, but a Hirshfeld surface analysis highlights weak inter­molecular contacts leading to π–π-stacked dimers linked by weak C—H⋯N contacts. The packing analysis confirms that most inter­molecular inter­actions involve hydrogen atoms. [ABSTRACT FROM AUTHOR]

This study presents the synthesis, crystal structure, and a Hirshfeld-surface analysis of the bioactive compound 5-methyl-1H-pyrazol-3-yl 4-nitro­benzene­sulfonate­(C10H9N3O5S), a pyrazole derivative with pharmacological potential. Pyrazoles are known for diverse bioactivities, and recent research emphasizes their role as a ‘privileged structure’ in drug design. Here, the asymmetric unit of the title compound contains two distinct mol­ecules, A and B, exhibiting differences in conformation resulting from variation in key torsion angles. These distinctions influence the mol­ecular orientation and inter­molecular inter­actions, with strong N—H⋯N and N—H⋯O hydrogen bonds forming a centrosymmetric tetra­mer stabilized by π–π stacking. Hirshfeld surface analysis readily confirms differing inter­molecular contacts for A and B, primarily involving hydrogen atoms and differences in their close contacts to nitro­gen and oxygen. This study offers further insight into the mol­ecular architecture and potential inter­actions of pyrazole-based drug candidates. [ABSTRACT FROM AUTHOR]

The crystal structure and a Hirshfeld surface analysis of the substituted anilinium salt 4-(dimethylazaniumyl)-2-hydroxyanilinium dichloride monohydrate, C8H14N2O+·2Cl- ·H2O, at low temperature (90 K) are presented. The organic cation is essentially planar: the r.m.s. deviation of its non-hydrogen atoms (aside from the two methyl groups) is 0.0045 A °. The methyl carbons are 1.3125 (12) A ° and 1.1278 (12) A ° either side of the mean plane. The crystal packing involves extensive hydrogen bonding of types O--H...Cl, N--H...Cl, N--H...OW, and OW--HW...Cl (where W = water), which arrange into chains of R2 4(12) motifs that combine to form corrugated layers parallel to (101). Atom-atom contacts for the cation primarily involve hydrogen, leading to the most abundant coverage percentages being 51.3% (H...H), 23.0% (H...Cl), 12.9% (H....O), and 9.7% (C...H). [ABSTRACT FROM AUTHOR]

The synthesis and crystal structure of a monoclinic polymorph of 2-amino-5-chlorobenzophenone oxime, C13H11ClN2O, are presented. The molecular conformation results from twisting of the phenyl and 2-amino-5-chloro benzene rings attached to the oxime group, which subtend a dihedral angle of 80.53 (4)°. In the crystal, centrosymmetric dimers are formed as a result of pairs of strong O--H--N hydrogen bonds. A comparison is made to a previously known triclinic polymorph, including differences in atom-atom contacts obtained via a Hirshfeld-surface analysis. [ABSTRACT FROM AUTHOR]

The synthesis, crystal structure and spectroscopic analysis of (E)-1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-3-(4-chlorophenyl)prop-2-en-1-one (C17H13ClO3), a substituted chalcone, are described. The overall geometry of the molecule is largely planar (r.m.s. deviation = 0.1742 JA), but slightly kinked, leading to a dihedral angle between the planes of the benzene rings at either side of the molecule of 8.31 (9)°. In the crystal, only weak interactions determine the packing motifs. These include C--H--O and C--H--Cl hydrogen bonds and n-n overlap of aromatic rings. [ABSTRACT FROM AUTHOR]

The synthesis and crystal structure of a monoclinic polymorph of 2-amino-5-chlorobenzophenone oxime, C13H11ClN2O, are presented. The molecular conformation results from twisting of the phenyl and 2-amino-5-chloro benzene rings attached to the oxime group, which subtend a dihedral angle of 80.53 (4)°. In the crystal, centrosymmetric dimers are formed as a result of pairs of strong O--H⋯N hydrogen bonds. A comparison is made to a previously known triclinic polymorph, including differences in atom-atom contacts obtained via a Hirshfeld-surface analysis. [ABSTRACT FROM AUTHOR]

The syntheses and crystal structures of four salts of amitriptynol (C20H25NO) with different carboxylic acids are described. The salts formed directly from solutions of amitriptyline (which first hydrolysed to amitriptynol) and the corresponding acid in acetonitrile to form amitriptynolium [systematic name: (3-{2-hydroxytricyclo[9.4.0.03,8]pentadeca-1(11),3,5,7,12,14-hexaen-2-yl}propyl)dimethylazanium] 4-methoxybenzoate monohydrate, C20H26NO+C8H7O3 -H2O, (I), amitriptynolium 3,4-dimethoxybenzoate trihydrate, C20H26NO+·C9H9O4 -3H2O, (II), amitriptynolium 2-chlorobenzoate, C20H26NO+·C7H4ClO2 -, (III), and amitriptynolium thiophene-2-carboxylate monohydrate, C20H26NO+·C5S-H2S-H2O, (IV). Compound (III) crystallizes with two cations, two anions and six water molecules in the asymmetric unit. The different conformations of the amitriptynolium cations are determined by the torsion angles in the dimethylamino-propyl chains and the -CH2-CH2- bridge between the benzene rings in the tricyclic ring system, and are complicated by disorder of the bridging unit in II and III. The packing in all four salts is dominated by N-H...O and O- H...O hydrogen bonds. Hirshfeld surface analyses show that the amitriptynolium cations make similar inter-species contacts, despite the distinctly different packing in each salt. [ABSTRACT FROM AUTHOR]

The crystal structures and Hirshfeld surface analyses of three salts of 1-(4-nitrophenyl)piperazine with 2-chlorobenzoic acid, 2-bromobenzoic acid and 2-iodobenzoic acid are reported. The chlorobenzoate salt, C10H14N3O2 +- C7H4ClO2- contains whole-ion-disordered cations and anions, which were modeled with two equivalent conformations with occupancies of 0.745 (10)/0.255 (10) and 0.563 (13)/0.437 (13), respectively. The bromobenzoate and iodobenzoate derivatives are isomorphous and crystallize as hemihydrates, viz. C10H14N3O2 +-C7H4BrO2 -0.5H2O and C10H14N3O2 +-C7H4IO2 -0.5H2O, respectively [the water molecule is disordered over two locations with occupancies of 0.276 (3)/0.223 (3) for the iodobenzoate derivative]. In the extended structures, all three salts feature an R4 4(12) loop of two anions and two cations linked by N-H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Syntheses and X-ray crystal structures of four 4-(4-methoxyphenyl)piperazin-1-ium (MeOPP) salts, with 2,2,2-trifluoroacetate, C11H17N2O+πC2F3O2- (I), 2,3,4,5,6-pentafluorobenzoate, C11H17N2O+πC7F5O2-πH2O (II), 4-iodobenzoate C11H17N2O+πC7H4IO2-πH2O (III), and 4-methylbenzoate, C11H17N2O+π- C8H7O2-πH2O (IV) anions are presented. The salts form directly from equimolar quantities of N-(4-methoxyphenyl)piperazine and the corresponding organic acid in methanol and crystallize from 1:1 methanol/ethyl acetate. Salt I is anhydrous whereas II, III, and IVare all monohydrates. In all cases, the MeOPP cation conformation is determined by the torsion about the N--C bond between the piperazinium and 4-methoxybenzene rings. Crystal packing in each structure is largely dictated by N--Hπ π πO and (in II, III, and IV) O--Hπ π πO hydrogen bonds, although each also features weak C--Hπ π πO-type hydrogen bonds. Salt II also has π-π-stacking interactions between cation and anion arene rings, and III exhibits Iπ π πI close contacts. [ABSTRACT FROM AUTHOR]

The structures and Hirshfeld surface analysis of three salts of 1-(4-nitrophenyl)- piperazine are discussed. In 4-(4-nitrophenyl)piperazin-1-ium salicylate (C10H14N3O2 +·C7H5O3-), there are strong hydrogen bonds between cation and anion and the 4-nitrophenyl substituent occupies an equatorial position in the piperazinium ring. The cation and anion are linked together by supramolecular interactions [graph-set notation of hydrogen bonding C²2(6) propagating in the a-axis direction]. Additionally, there is π-π stacking involving the salicylate anion and the piperazinium cation in adjacent asymmetric units as well as a C--H· · ·π interaction between a hydrogen atom on the piperazine ring and the phenyl ring within the salicyclate anion. In bis[4-(4-nitrophenyl)piperazin-1-ium] bis(4-fluorobenzoate) trihydrate (2C10H14N3O2 +·2C7H4FO2-·3H2O), there are two cations, two anions, and three water molecules of solvation in the asymmetric unit, all linked by hydrogen bonds [graph-set notation of hydrogen bonding R²2(20) between adjacent cations and R³3(9) between a cation and its adjacent anion]. In the anion, the 4-nitrophenyl ring occupies an axial substitution position in the piperazinium ring, which is relatively rare. Within the asymmetric unit, the phenyl groups in the cations show an offset π-π interaction. Additionally, there is a C--H· · ·π interaction between a hydrogen atom on the phenyl ring within a cation and the phenyl ring within an anion. In 4-(4-nitrophenyl)piperazin-1-ium 3,5-dinitrobenzoate (C10H14N3O2 +·C7H4N2O6-), there is a strong N--H· · ·O hydrogen bond linking the cation and anion and the 4-nitrophenyl ring occupies an axial substitution position in the piperazinium ring, as seen in the previous structure. In the crystal, the cation and the anion form a complex threedimensional hydrogen-bonded array involving R²2(8), R44(12) and R44(20) rings propogating in the a-axis direction. The nitrophenyl group is disordered with occupancies of 0.806 (10) and 0.194 (10). [ABSTRACT FROM AUTHOR]

The syntheses and crystal structures are presented for four organic salts of the 4-(4-nitrophenyl)piperazinium cation, namely, 4-(4-nitrophenyl)piperazinium hydrogen succinate, C10H14N3O2+·C4H5O4- (I), 4-(4-nitrophenyl)piperazinium 4-aminobenzoate monohydrate, C10H14N3O2+·C7H6NO2-·H2O (II), 4-(4-nitrophenyl)piperazinium 2-(4-chlorophenyl)acetate, C10H14N3O2+·C8H6ClO2- (III) and 4-(4-nitrophenyl)piperazinium 2,3,4,5,6-pentafluorobenzoate, C10H14N3O2+·C7F5O2- (IV). The salts form from mixtures of N-(4-nitrophenyl)piperazine and the corresponding acid [succinic acid (I), 4-aminobenzoic acid (II), 2-(4-chlorophenyl)acetic acid (III) and 2,3,4,5,6-pentafluorobenzoic acid (IV)] in mixed solvents of methanol and ethyl acetate. Salts I, III, and IV are anhydrous, whereas II is a monohydrate. In each structure, the overall conformation of the cation is determined by the disposition of the exocyclic N--C bond of the piperazine ring (either axial or equatorial) and twists about the N--C bond between the piperazine ring and its attached 4-nitrophenyl ring. The packing motifs in each structure are quite different, though all are dominated by strong N--H⋯O hydrogen bonds, which are augmented in I and II by O--H⋯O hydrogen bonds, and in III by a π-π stacking interaction between inversion-related 4-nitrophenyl groups. [ABSTRACT FROM AUTHOR]

C29H30N6O6, monoclinic, P21/c (no. 14), a = 12.3134(3) Å, b = 21.2095(4) Å, c = 10.8503(2) Å, β = 100.549(1)°, V = 2785.8 Å3, Z = 4, Rgt(F) = 0.0422, wRref(F2) = 0.1205, T = 200 K

The crystal structure of ethiprole {systematic name: 5-amino-1-[2,6-dichloro- 4-(trifluoromethyl)phenyl]-4-ethanesulfinyl-1H-imidazole-3-carbonitrile}, C13H9Cl2F3N4OS, a phenylpyrazole-based insecticide, is presented. The pyrazole ring carries four substituents: an N-bound 2,6-dichloro-4-trifluoromethylphenyl ring and C-bound amine, ethanesulfinyl, and cyano groups. The sulfur atom of the ethanesulfinyl group is trigonal--pyramidal and stereogenic. The structure exhibits whole-molecule configurational disorder due to superposition of enantiomers. The crystal packing is dominated by strong N--H • • • O and N--H • • • N hydrogen bonds, which form R44(18) and R2 2(12) ring motifs. Since the ethiprole molecule is quite small, and structure solution and refinement were straightforward, the structure presents a convenient instructional example for modelling whole-body disorder of a non-rigid molecule. To this end, a step-bystep overview of the model-building and refinement process is also given. The structure could form the basis of a useful classroom, practical, or workshop-style example. [ABSTRACT FROM AUTHOR]

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]

Three organic salts of sparfloxacin, a difluorinated third-generation fluoroquinolone antibiotic, have been synthesized and their crystal structures determined. The salts, sparfloxacinium 4-nitrobenzoate dihydrate, C19H23F2N4O3 +·C7H4NO4 -·2H2O (I), sparfloxacinium 2-phenylacetate, C19H23F2N4O3 +·C8H7O2- (II), and sparfloxacinium 4-methylbenzoate trihydrate, C19H23F2N4O3 +·C8H7O2 -·3H2O (III), exhibit similar inter-species packing interactions. The overall crystal structures each, however, have their own distinct characteristics, which are described here along with a Hirshfeld surface analysis of the various atom-atom contacts involving the sparfloxacinium cations. In the crystal structure of III, an extended supramolecular tape of edgefused hydrogen-bonded water pentagons was found. These pentagonal water and tape motifs are compared to related constructs in a broad selection of structure types, ranging from macromolecules to small molecules, clathrates, and exotic 'ice' formations on clean metal surfaces. [ABSTRACT FROM AUTHOR]

The crystal structures of three salts, namely N-(4-methoxyphenyl)piperazin-1-ium ethoxybenzoate monohydrate (I), N-(4-methoxyphenyl)piperazin-1-ium methoxybenzoate monohydrate (II) and N-(4-methoxyphenyl)piperazin-1-ium hydroxybenzoate monohydrate (III), have been determined and compared. In each of them, the ionic components and the water molecules are linked by a combination of N—H···O and O—H···O hydrogen bonds to form infinite chains of edge-fused centrosymmetric rings running parallel to the [100] direction. The C—H···O, C—H···π(arene) interactions and O—H···O in (III) are responsible for the further propagation of the aforementioned chains into di-periodic layers or tri-periodic networks. From an energetic point of view, all structures are primarily di-periodic; the very strong ionic interactions determine the periodicity. For comparison purposes, quantum chemical calculations were performed to show the difference between the ionic and neutral components. The energy of the hydrogen-bonded ring motifs was also estimated. [ABSTRACT FROM AUTHOR]

The structure of 2-chloro-1-(3-hydroxyphenyl)ethanone, C8H7ClO2, an α-haloketone is described. The molecule is planar (r.m.s. deviation = 0.0164 A °) and in the crystal, inversion-symmetric dimers are formed as a result of pairs of strong O--H···O and weak C--H···O hydrogen bonds. A brief comparison is made with structurally related compounds deposited in the CSD. In addition, the synthesis and some spectroscopic details are presented. [ABSTRACT FROM AUTHOR]

The structure of the title compound, C15H8N4Cl2F6OS, a phenylpyrazole-based insecticide related to ethiprole, fipronil, and derivatives thereof is presented. The pyrazole ring has four chemically diverse substituents, namely a nitrogenbound 2,6-dichloro-4-trifluoromethylphenyl and carbon-bound cyano, ethylsulfanyl, and 2,2,2-trifluoroacetamide groups. The pyrazole and phenyl rings are perpendicular, subtending a dihedral angle of 89.80 (5)°. In the crystal, strong N--H···O hydrogen bonds link the molecules into chains that extend parallel to the a-axis. [ABSTRACT FROM AUTHOR]

Benzyl N'-[(E)-2-hydroxybenzylidene]hydrazinecarboxylate, C15H14N2O3 (I) and benzyl N'-[(E)-5-bromo-2-hydroxybenzylidene]hydrazinecarboxylate (II), C15H13BrN2O3, have been synthesized by the reaction of either 2-hydroxybenzaldehyde or 5-bromo-2-hydroxybenzaldehyde with benzyl carbazate, respectively. Both the compounds crystallize in the monoclinic crystal system with space groups Pn (Z' = 1, I) and P21/c (Z' = 2, II). Molecular conformations in each structure are similar, and both structures feature strong intramolecular O--H--N hydrogen bonds, which form S(6) ring motifs. There are also strong N--H--O and weak C--H--O hydrogen bonds in both structures, but their modes of packing within their respective crystals are markedly different. Some comparisons are made with the structures of a few related compounds. [ABSTRACT FROM AUTHOR]

The low (90 K) and room (298 K) temperature crystal structures of topiramate azidosulfate [systematic name 2,3:4,5-bis-O-(1-methylethylidene)-ß-D-fructopyranose azidosulfate], C12H19N3O8S, an intermediate in the synthesis of the anti-convulsant drug topiramate, are described. Topiramate azidosulfate (I) finds use as a reference impurity standard for topiramate. A modified synthesis and some spectroscopic details are also presented. [ABSTRACT FROM AUTHOR]

The structure of ebastinium hydrogen fumarate {systematic name: 1-[4-(4-tertbutylphenyl)-4-oxobutyl]-4-(diphenylmethoxy)piperidin-1-ium (E)-3-carboxy-1-hydroxyprop-2-en-1-olate}, C32H40NO2 +⋅C4H3O4, 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. In the crystal, cation-anion pairs are linked by a strong N--H⋅ ⋅ ⋅O hydrogen bond [N⋅ ⋅ ⋅O = 2.697 (11) A ° ]. These units interact via weaker C--H⋅ ⋅ ⋅O and C--H⋅ ⋅ ⋅⋅ contacts to form layers lying parallel to the bc plane. The hydrogen fumarate anions are linked by a very short O--H⋅ ⋅ ⋅O hydrogen bond [O⋅ ⋅ ⋅O = 2.5402 (17) A ° ], augmented by weak C--H⋅ ⋅ ⋅O contacts into pairs of R2 2(6) ring motifs to form chains that extend parallel to the b-axis direction. Comparisons to similar crystal structures are presented. [ABSTRACT FROM AUTHOR]

Crystal structures are reported for two mol­ecular salts containing the 4-(4-nitro­phen­yl)piperazin-1-ium cation. Co-crystallization from methanol/ethyl acetate solution of N-(4-nitro­phen­yl)piperazine with benzoic acid gives the benzoate salt, which crystallizes as a monohydrate, C10H14N3O2·C7H5O2·H2O, (I), and similar co-crystallization with 3,5-di­nitro­salicylic acid yields the 2-carb­oxy-4,6-di­nitro­phenolate salt, C10H14N3O2·C7H3N2O7, (II). In the structure of (I), a combination of O--H...O, N--H...O and C--H...O hydrogen bonds links the components into sheets, while in the structure of (II), the supra­molecular assembly, generated by hydrogen bonds of the same types as in (I), is three dimensional. Comparisons are made with the structures of some related compounds. [ABSTRACT FROM AUTHOR]