2-(Phenyl­carbonothio­ylsulfan­yl)acetic acid

The title compound, C9H8O2S2, can be used as a chain transfer agent and may be used to control the behavior of polymerization reactions. O—H⋯O hydrogen bonds of moderate character link the mol­ecules into dimers. In the crystal, the dimers are linked into sheets by C—H⋯O inter­actions, forming R 4 2(12) and R 2 2(8) edge-fused rings running parallel to [101]. There are no inter­molecular inter­actions involving the S atoms

Weak C-H...Cl-Pd interactions toward conformational polymorphism in trans-dichloridobis (triphenylphosphane) palladium (II)

A new triclinic polymorph of the title compound, [PdCl2(C18H15P)2], has two independent mol­ecules in the unit cell, with the Pd atoms located on inversion centres. One mol­ecule has an eclipsed conformation, whereas the second mol­ecule adopts a gauche conformation. The mol­ecules with a gauche conformation are involved in weak inter­molecular C-H...Cl-Pd inter­actions with symmetry-related mol­ecules. It is suggested that C-H...Cl-Pd inter­actions are mainly responsible for the existence of conformational differences, which contribute to the polymorph formation. In the crystal, there are layers of eclipsed and gauche mol­ecules separated by normal van der Waals inter­actions.FAPESP (09/08131-1)CNPqCAPESPROE

Rational Design of a Famotidine-Ibuprofen Coamorphous System: An Experimental and Theoretical Study

Famotidine (FMT) and ibuprofen (IBU) were used as model drugs to obtain coamorphous systems, where the guanidine moiety of the antacid and the carboxylic group of the nonsteroidal anti-inflammatory drug could potentially participate in H-bonds leading to a given structural motif. The systems were prepared in 3:7, 1:1, and 7:3 FMT and IBU molar ratios, respectively. The latter two became amorphous after 180 min of comilling. FMT-IBU (1:1) exhibited a higher physical stability in assays at 4, 25, and 40 °C up to 60 days. Fourier transform infrared spectroscopy accounted for important modifications in the vibrational behavior of those functional groups, allowing us to ascribe the skill of 1:1 FMT-IBU for remaining amorphous to equimolar interactions between both components. Density functional theory calculations followed by quantum theory of atoms in molecules analysis were then conducted to support the presence of the expected FMT-IBU heterodimer with consequent formation of a R28 structural motif. The electron density (ρ) and its Laplacian (2 ρ) values suggested a high strength of the specific intermolecular interactions. Molecular dynamics simulations to build an amorphous assembly, followed by radial distribution function analysis on the modeled phase were further employed. The results demonstrate that it is a feasible rational design of a coamorphous system, satisfactorily stabilized by molecular-level interactions leading to the expected motif.Fil: Russo, Marcos Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Baldoni, Hector Armando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Davila, Yamina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Brusau, Elena Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Ellena, Javier A.. Universidade de Sao Paulo; BrasilFil: Narda, Griselda Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin

4-Methyl­phenyl 4-bromo­benzoate

In the title compound, C14H11BrO2, an ester formed from the reaction of 4-methyl­phenol with 4-bromo­benzoyl­chloride, the dihedral angle between the benzene rings is 54.43 (7)°, indicating a twist in the mol­ecule. In the crystal, weak C—H⋯O inter­actions link the mol­ecules into supra­molecular layers in the bc plane, and these are connected along the a axis by Br⋯Br contacts [3.6328 (5) Å]

4-formyl-2-nitrophenyl 2-chlorobenzoate

In the title compound, C14H8ClNO5, the benzene rings form a dihedral angle of 19.55 (9)° . The mean plane of the central ester group [r.m.s. deviation = 0.024 A] forms dihedral angles of 53.28 (13) and 36.93 (16)°, respectively, with the nitro- and chloro-substituted rings. The nitro group forms a dihedral angle of 19.24 (19)° with the benzene ring to which it is attached. In the crystal, molecules are linked by weak C- H...O hydrogen bonds, forming C(7) chains, which run along [100]

4-formyl-2-nitrophenyl 4-bromobenzoate

In the title compound, C14H8BrNO5, the benzene rings form a dihedral angle of 62.90 (7)° . The central ester group is twisted away from the nitro-substituted and bromo-substituted rings by 71.67 (7) and 8.78 (15)° , respectively. The nitro group forms a dihedral angle of 7.77 (16)° with the benzene ring to which it is attached. In the crystal, molecules are linked by weak C-H O interactions, forming C(12) chains which run along [001]. Halogen–halogen interactions [Br Br = 3.523 (3) Å] within the chains stabilized by C-H O interactions are observed

cis-Bis[1,1-dibenzyl-3-(furan-2-yl­carbonyl)thio­ureato-κ2 O,S]copper(II)

In the title compound, [Cu(C20H17N2O2S)2], the CuII atom is coordinated by the S and O atoms of two 1,1-dibenzyl-3-(furan-2-ylcarbon­yl)thio­ureate ligands in a distorted square-planar geometry. The two O and two S atoms are mutually cis to each other. The Cu—S and Cu—O bond lengths lie within the ranges of those found in related structures. The dihedral angle between the planes of the two chelating rings is 26.15 (6)°

Synthesis, structural characterization and conformational aspects of nostoclide analogues

The synthesis and structural analysis of a set of nostoclide analogues with potential herbicide activity is described. The influence of intra- and intermolecular hydrogen bonding, as well as other interactions on the conformation and packing of the compounds is thoroughly described using DFT calculations and single crystal X-ray diffraction analyses. All lactones exhibited the Z configuration as confirmed by NOESY experiments and by single crystal X-ray diffraction measurementsCNPQFAPEMI

Experimental and theoretical investigation of molecular structure and conformation of the 4-isopropylthioxanthone

In this study, the molecular structure and conformational analyses of the 4-isopropylthioxanthone (4-ITX) are reported according to experimental and theoretical results. The compound crystallizes in the centrosymmetric PView the MathML source space group with only one molecule in the asymmetric unit, presenting the most stable conformation, in which the three fused-rings adopt a planar geometry, and the isopropyl group assumes a torsional angle with less sterical hindrance. The structural and conformational analyses were performed using theoretical calculations such as Hartree–Fock (HF), DFT method in combination with 6-311G(d,p) and 6-31++G(d,p) and the results were compared with infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The supramolecular assembly of 4-ITX is kept by non-classical C-H⋯O hydrogen bonds and weak interactions such as π-π stacking. 4-ITX was also studied by 1H and 13C NMR spectroscopy. UV-Vis absorption spectroscopic properties of the 4-ITX showed the long-wavelength maximum shifts towards high energy when the solvent polarity increases.FAPESP (09/08131-1)CNPqCAPES/PROE

On an accidental degeneracy in the 31P{¹H} NMR chemical shifts in ruthenium diphosphine complexes

The [RuCl(bipy)(dppb)(4-pic)]PF6 complex was prepared and fully characterized. The X-ray crystal structure of this complex was determined in order to make an unambiguous distinction between the two possible positions of the 4-methylpyridine ligand (4-pic) in the compound: trans to phosphorus atom or trans to nitrogen atom. The [RuCl(bipy)(dppb)(4-pic)]PF6 complex exhibits an unusual temperature-dependent accidental degeneracy of the 31P chemical shifts in its solution NMR spectrum