New series of 1-(2-fluorobenzyl)piperazine triazoles 7(a-k) have been synthesized and evaluated for anticancer activity. The molecular structures of all the compounds were established by employing 1H NMR, 13C NMR and mass spectral analysis. In vitro anticancer activity was evaluated using MTT assay against MCF7 breast cancer cell line. Compounds 7i and 7j bearing 4-fluorophenyl and 2-fluorophenyl pendant from triazole substituent phenyl ring exhibited the highest anticancer efficacy with IC50 values of 12.09 µg/mL and 15.12 µg/mL, respectively. A molecular docking study conducted on human HER2 complexed with hercepatin fab was acquired from Protein Data Bank (PDB ID: 1N8Z). Molecular docking studies demonstrated Leu443, Gly442 and Leu27 as key residues interacting with active compounds.

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 center dot center dot center dot N and N-H center dot center dot center dot O hydrogen bonds forming a centrosymmetric tetramer stabilized by pi-pi 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.

The low-temperature crystal structures of four organic salts of the anti-spasmodic drug trihexyphenidyl are presented.

Syntheses and X-ray crystal structures of four 4-(4-meth-oxy-phen-yl)piperazin-1-ium (MeOPP) salts, with 2,2,2-tri-fluoro-acetate, C11H17N2O+·C2F3O2 - (I), 2,3,4,5,6-penta-fluoro-benzoate, C11H17N2O+·C7F5O2 -·H2O (II), 4-iodo-benzoate C11H17N2O+·C7H4IO2 -·H2O (III), and 4-methyl-benzoate, C11H17N2O+·C8H7O2 -·H2O (IV) anions are presented. The salts form directly from equimolar qu-anti-ties of N-(4-meth-oxy-phen-yl)piperazine and the corresponding organic acid in methanol and crystallize from 1:1 methanol/ethyl acetate. Salt I is anhydrous whereas II, III, and IV are all monohydrates. In all cases, the MeOPP cation conformation is determined by the torsion about the N-C bond between the piperazinium and 4-meth-oxy-benzene rings. Crystal packing in each structure is largely dictated by N-H⋯O and (in II, III, and IV) O-H⋯O hydrogen bonds, although each also features weak C-H⋯O-type hydrogen bonds. Salt II also has π-π-stacking inter-actions between cation and anion arene rings, and III exhibits I⋯I close contacts.

The synthesis and crystal structure of C3HF3N2OS, systematic name 5-(trifluoromethyl)-1,3,4-thiadiazol-2(3H)-one (5-TMD-2-one), a compound containing the pharmacologically important heterocycle 1,3,4-thiadiazole, is presented. The asymmetric unit comprises six independent molecules (Z′ = 6), all of which are planar. The r.m.s. deviations from each mean plane range from 0.0063 to 0.0381 Å, not including the CF3 fluorine atoms. Within the crystal, two of the molecules form hydrogen-bonded dimers that in turn combine with inversion-related copies to form tetrameric constructs. Similar tetramers, but lacking inversion symmetry, are formed by the remaining four molecules. The tetramers are linked into tape-like motifs by S...O and O...O close contacts. The environments of each symmetry-independent molecule were compared via a Hirshfeld surface analysis. The most abundant atom–atom contacts are between fluorine atoms, while the strongest result from N—H...O hydrogen bonds.

The syntheses and crystal structures are presented for four organic salts of the 4-(4-nitro-phen-yl)piperazinium cation, namely, 4-(4-nitro-phen-yl)piperazinium hydrogen succinate, C10H14N3O2+·C4H5O4- (I), 4-(4-nitro-phen-yl)piperazinium 4-amino-benzoate monohydrate, C10H14N3O2+·C7H6NO2-·H2O (II), 4-(4-nitro-phen-yl)piperazinium 2-(4-chloro-phen-yl)acetate, C10H14N3O2+·C8H6ClO2- (III) and 4-(4-nitro-phen-yl)piperazinium 2,3,4,5,6-penta-fluoro-benzoate, C10H14N3O2+·C7F5O2- (IV). The salts form from mixtures of N-(4-nitro-phen-yl)piperazine and the corresponding acid [succinic acid (I), 4-amino-benzoic acid (II), 2-(4-chloro-phen-yl)acetic acid (III) and 2,3,4,5,6-penta-fluoro-benzoic 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-nitro-phenyl 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 inter-action between inversion-related 4-nitro-phenyl groups.

The crystal structure of ethiprole {systematic name: 5-amino-1-[2,6-di-chloro-4-(tri-fluoro-meth-yl)phen-yl]-4-ethane-sulfinyl-1H-imidazole-3-carbo-nitrile}, C13H9Cl2F3N4OS, a phenyl-pyrazole-based insecticide, is presented. The pyrazole ring carries four substituents: an N-bound 2,6-di-chloro-4-tri-fluoro-methyl-phenyl ring and C-bound amine, ethane-sulfinyl, and cyano groups. The sulfur atom of the ethane-sulfinyl group is trigonal-pyramidal and stereogenic. The structure exhibits whole-mol-ecule configurational disorder due to superposition of enanti-omers. The crystal packing is dominated by strong N-H⋯O and N-H⋯N hydrogen bonds, which form R 4 4(18) and R 2 2(12) ring motifs. Since the ethiprole mol-ecule 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 mol-ecule. To this end, a step-by-step 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.

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.

The syntheses and crystal structures of four salts of amitriptynol (C20H25NO) with different carb-oxy-lic acids are described. The salts formed directly from solutions of amitriptyline (which first hydrolysed to amitriptynol) and the cor-responding acid in aceto-nitrile to form amitriptynolium [sys-tem-atic name: (3-{2-hy-droxy-tri-cy-clo[9.4.0.03,8]penta-deca-1(11),3,5,7,12,14-hexa-en-2-yl}pro-pyl)di-methyl-az-an-ium] 4-meth-oxy-benzoate monohydrate, C20H26NO+·C8H7O3 -·H2O, (I), ami-triptynolium 3,4-di-meth-oxy-benzoate trihydrate, C20H26NO+·C9H9O4 -·3H2O, (II), amitriptynolium 2-chloro-benzoate, C20H26NO+·C7H4ClO2 -, (III), and amitriptynolium thio-phene-2-carboxyl-ate monohydrate, C20H26NO+·C5H3O2S-·H2O, (IV). Compound (III) crystallizes with two cations, two anions and six water mol-ecules in the asymmetric unit. The different conformations of the amitriptynolium cations are determined by the torsion angles in the di-methyl-amino-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.

The synthesis and crystal structure of the title compound, C12H16FNO3S, which is related to the herbicide flufenacet, are presented. The dihedral angle between the amide group and the fluorinated benzene ring is 87.30 (5)° and the N—C—C—S torsion angle defining the orientation of the methylsulfonyl substituent relative to the amide group is 106.91 (11)°. In the crystal, inversion-related molecules form dimers as a result of pairwise C—H...O hydrogen bonds, which appear to be reinforced by short O...π contacts [O...Cg = 3.0643 (11) Å]. A Hirshfeld surface analysis was used to quantify the various types of intermolecular contacts, which are dominated by H atoms.

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 Å), 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 π–π overlap of aromatic rings.

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.

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 edge-fused 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.

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-hy-droxy-benzaldehyde or 5-bromo-2-hy-droxy-benzaldehyde 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). Mol-ecular conformations in each structure are similar, and both structures feature strong intra-molecular 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.

The structure of the title compound, C18H13NO4, shows that the whole molecule is almost planar but with a dihedral angle between the two phenyl rings of 19.22 (5)°. The molecules are linked by C—H...O interactions, forming sheets in the (21\overline{1}) plane.

We report a simple and efficient silicon wet etchant HNA (Hydrofluoric acid, Nitric acid, Acetic acid) for the stiction free release of silicon nitride/metal micro/nanomechanical structures. The HNA concentration was varied with the aim of developing a slow etch rate, which could be utilized to suspend the micron and sub-micron cantilever and fixed beam structures. The etch rate was found to decrease with decrease in HF and increase in HNO3 concentrations. Smooth surface and high selectivity are obtained in case of high HNO3 content. The obtained etchant with a slow etch rate of 440 nm/minute was successfully utilized for the release of silicon nitride cantilevers and fixed beam structures of 500 nm, 2 mu m and 5 mu m widths with varying lengths. The resonance frequency of suspended cantilevers characterized by Laser Doppler Vibrometer is in close agreement with the COMSOL simulated resonating frequencies proving that the etching process has been precise without changes to cantilever dimensions. In addition, the generated etchant was successfully used in releasing chrome/gold nanobeams as well without any damage to the metal layers. (C) 2020 Elsevier Ltd. All rights reserved.

A highly efficient technique for the generation of dense and homogeneous Au-nanodroplets using Anodic Aluminium Oxide template (AAO) for the fabrication of single crystal gold encrusted array of silicon nanowires (SiNWs) was successfully developed. In interest of extending AAO's practical applicability, the Au-thin film sandwiched between Si-substrate and AAO was torn-up into small nanodroplets at annealing temperature followed by removal of AAO template before VLS growth instead of growing SiNWs directly in presence of AAO template. It's observed that smaller Au-nanodmplets are mandatory to yield dense array of SiNWs, further, size of formed Au-droplets is directly relied on AAO pore-size. Thus, construction of desired pore diameter on AAO was critically controlled by the application of voltage in presence of different etchants (sulfuric acid (SA), oxalic acid (OA) and phosphoric acid (PA)). Among the different etchants used SA demonstrated smaller AAO-pore size at a specific voltage and concentration. Further, obtained smaller Au-nanodmplets (from SA etched AAO) exhibited a denser array of SiNWs on VLS growth at particular set of experimental conditions. Characterization by advanced techniques such as UV-Vis spectroscopy, Micro-Raman spectroscopy, Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), High-Angle Angular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM) and Energy Dispersive X-ray Spectroscopy (EDX) revealed that the formed SiNWs were of 199 +/- 43 nm diameter with well-decorated gold nano encrustations on the surface and at the tip. The formed SiNWs were in resemblance with SiNWs obtained from high precision e-beam Lithography, evidencing the superiority of the current method.

Cobalt(II) chloride catalyses the conversion of a variety of aldoximes, including salicylaldoxime and substituted salicylaldoximes, into corresponding nitriles in the presence of an inorganic base in acetonitrile. The reaction proceeds under mild conditions and the yields are generally very good to excellent.

A new highly efficient catalytic procedure for the Friedel–Crafts acylation of electron rich aromatics is reported. Cobalt(II) acetylacetonate catalyses the acylation of anisole, thioanisole, and toluene with a variety of acyl chlorides in nitromethane and acetonitrile under mild conditions. The catalyst is found to be reusable and the acylation is regioselective, and affords exclusively C-4 acylated products in excellent yields.