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The structures of six benzene and three naphthalene derivatives involving bromo, bromomethyl and dibromomethyl substituents, namely, 1,3‐dibromo‐5‐(dibromomethyl)benzene, C7H4Br4, 1,4‐dibromo‐2,5‐bis(bromomethyl)benzene, C8H4Br6, 1,4‐dibromo‐2‐(dibromomethyl)benzene, C7H4Br4, 1,2‐bis(dibromomethyl)benzene, C8H6Br4, 1‐(bromomethyl)‐2‐(dibromomethyl)benzene, C8H7Br3, 2‐(bromomethyl)‐3‐(dibromomethyl)naphthalene, C12H9Br3, 2,3‐bis(dibromomethyl)naphthalene, C12H8Br4, 1‐(bromomethyl)‐2‐(dibromomethyl)naphthalene, C12H9Br3, and 1,3‐bis(dibromomethyl)benzene, C8H6Br4, are presented. The packing patterns of these compounds are dominated by Br...Br contacts and C—H...Br hydrogen bonds. The Br...Br contacts, shorter than twice the van der Waals radius of bromine (3.7 Å), seem to play a crucial role in the crystal packing of all these compounds. The occurrence of Type I and Type II interactions is also discussed briefly, considering the effective atomic radius of bromine, as is their impact on the packing of molecules in the individual structures. [ABSTRACT FROM AUTHOR]

Introduction. In order to improve the efficacy of intravoxel incoherent motion (IVIM) parameters in characterising specific tissues, a new concept is introduced: the perfusion–diffusion ratio (PDR), which expresses the relationship between the signal S b decline rate as a result of IVIM and the rate of signal S b decline due to diffusion. The aim of this study was to investigate this novel approach in the differentiation of solid primary liver lesions. Material and Methods. Eighty-three patients referred for liver MRI between August 2017 and January 2020 with a suspected liver tumour were prospectively examined with the standard liver MRI protocol extended by DWI-IVIM sequence. Patients with no liver lesions, haemangiomas, or metastases were excluded. The final study population consisted of 34 patients with primary solid liver masses, 9 with FNH, 4 with regenerative nodules, 10 with HCC, and 11 with CCC. The PDR coefficient was introduced, defined as the ratio of the rate of signal S b decrease due to the IVIM effect to the rate of signal S b decrease due to the diffusion process, for b = 0. Results. No significant differences were found between benign and malignant lesions in the case of IVIM parameters (f , D , or D ∗ ) and ADC. Significant differences were observed only for PDR, with lower values for malignant lesions (p = 0.03). The ROC analysis yielded an AUC value for PDR equal to 0.74, with a cut-off value of 5.06, sensitivity of 81%, specificity of 77%, and accuracy of 79%. Conclusion. PDR proved to be more effective than IVIM parameters and ADC in the differentiation of solid benign and malignant primary liver lesions. [ABSTRACT FROM AUTHOR]

Cathinones belong to a group of compounds of great interest in the new psychoactive substances (NPS) market. Constant changes to the chemical structure made by the producers of these compounds require a quick reaction from analytical laboratories in ascertaining their characteristics. In this article, three cathinone derivatives were characterized by X‐ray crystallography. The investigated compounds were confirmed as: 1‐[1‐(4‐methylphenyl)‐1‐oxohexan‐2‐yl]pyrrolidin‐1‐ium chloride (1, C17H26NO+·Cl−, the hydrochloride of 4‐MPHP), 1‐(4‐methyl‐1‐oxo‐1‐phenylpentan‐2‐yl)pyrrolidin‐1‐ium chloride (2; C16H24NO+·Cl−, the hydrochloride of α‐PiHP) and methyl[1‐(4‐methylphenyl)‐1‐oxopentan‐2‐yl]azanium chloride (3; C13H20NO+·Cl−, the hydrochloride of 4‐MPD). All the salts crystallize in a monoclinic space group: 1 and 2 in P21/c, and 3 in P21/n. To the best of our knowledge, this study provides the first detailed and comprehensive crystallographic data on salts 1–3. [ABSTRACT FROM AUTHOR]

During the last decade, a substantial growth in new psychoactive substances (NPS) has been recorded. Within this group, a considerably fast-growing sub-group is represented by the opioids, which are based on modifications of the fentanyl structure. In this study, identification and analytical characterization of a new fentanyl derivative, 4-fluorobutyrfentanyl (1-((4-fluorophenyl)(1-phenethylpiperidin-4-yl)amino)butan-1-one, 4-FBF), is described. Apart from the seized powder, 4-FBF was also identified in the e-cigarette liquid secured in Case 1. The concentration of the compound in the liquid was 35 mg/mL. The main component of the liquid was glycerol, and nicotine was also present. This substance was detected in seized material that originated from the illegal drug market in Poland. To the best of the authors' knowledge, this report presents the first two analytically confirmed cases of fatal intoxication associated with 4-FBF. Case 1 was a 26-year-old male drug user who was found dead at home. Case 2 was a 25-year-old female, occasional user of NPS and drugs, who was also found dead at home. The concentrations of 4-FBF in blood were 91 and 112 ng/mL and in urine 200 and 414 ng/mL. The concentrations of 4-FBF in liver and kidney were 902 and 411 ng/g, and 136 and 197 ng/g, for Case 1 and Case 2, respectively. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article discusses the crystal structures of the organic compound, N,N'-bis[4-(diethylamino)phenyl]-terephthaldiamide. It also examines the two concomitant polymorphs of the compound. It cites that each molecules of the compound is connected to four neighbouring molecules, two lower and two higher, to form a crosslinked three-dimensional pattern rather than the standard ladder.

The article describes a new polymorph of 1,4-dibromo-2,5-dimethylbenzene: H···Br and Br···¶ which is the same as the known polymorph (Ia) but with Z=2, an imposed inversion symmetry rather than Z=4. The polymer was made from research on secondary interactions in brominated aromatic hydrocarbons like "weak" C-H···Br hydrogen bonds, Br···Br halogen bonds, ¶-¶ stacking, and H···¶ and Br···¶ contacts.

The title compound, C9H7NS, crystallizes as the thione tautomer with Z′ = 8 (four independent dimers with local inversion symmetry via two N—H…S=C hydrogen-bond systems). The dimers are arranged in chains parallel to [&1macr;10], each chain being crystallographically independent. These chains are associated into layers via stacking of ring systems. The Z′ value can be rationalized in terms of a factor 2 for dimer formation without crystallographic symmetry and an additional factor 4 for differing stacking environments. [ABSTRACT FROM AUTHOR]

The mol­ecule of the title compound, C20H16Br2, displays crystallographic inversion symmetry. Two C—H⋯Br inter­actions link the mol­ecules into layers parallel to ( 11). The shortest Br⋯Br contact is 4.1599 (4) Å. [ABSTRACT FROM AUTHOR]

The title compound, C22H22, displays no crystallographic symmetry. The central benzene ring subtends inter­planar angles of 63.00 (6) and 66.09 (6)° (in opposite senses) to the outer rings. The crystal packing involves two short C—H⋯π contacts. [ABSTRACT FROM AUTHOR]

The title compound, C24H20S2, adopts an anti conformation with approximately parallel ring systems; the interplanar angle is 5.57 (8)°. Apart from the outer ring of the meta naphthalene, the molecule displays approximate mirror symmetry. [ABSTRACT FROM AUTHOR]

The title compound, C24H24N2O2, crystallizes as a triclinic polymorph from dimethyl­formamide and a monoclinic polymorph from ethanol. In both forms, the mol­ecule displays crystallographic inversion symmetry, and the packing involves translationally related `ladders' of mol­ecules connected by N—H⋯O=C hydrogen bonds. Differences between the structures can be rationalized in terms of weak C—H⋯O contacts. Powder and differential scanning calorimetry investigations of new samples gave no evidence for the triclinic form, and it seems to represent a disappearing polymorph. [ABSTRACT FROM AUTHOR]

In the title compound, C(48)H(38)N(4)O(8)·C(3)H(6)O(2), the porphyrin mol-ecule is centrosymmetric. The propionic acid solvent mol-ecule is disordered over two sets of sites with equal occupancy factors. The porphyrin central core is almost planar, with an r.m.s. deviation of the fitted atoms of 0.045 Å. The substituent benzene rings make dihedral angles of 70.37 (4) and 66.95 (4)° with respect to the porphyrin core plane. The crystal structure is stabilized by an inter-esting network of hydrogen bonds. Porphyrin mol-ecules are connected by O-H⋯O hydrogen bonds creating ribbons running along the [101] direction. Weak C-H⋯O hydrogen bonds connect separate mol-ecular ribbons in the [110] direction, creating (-111) layers. Intra-molecular N-H⋯N hydrogen bonds also occur. The propionic acid molecules are connected by pairs of -H⋯O hydrogen bonds, creating dimers.

In the title compound, C(14)H(12)Br(2), the Br atoms lie on opposite sides of their ring plane. The biphenyl inter-planar angle is 53.52 (8)°. The packing is characterized by several H⋯Br contacts to each Br atom, but at long distances of 3.07-3.43 Å.

In the title compound, C(13)H(18)O(5)S, the five-membered ring has an envelope conformation. The packing involves four C-H⋯O inter-actions, three of which combine to form layers of mol-ecules parallel to the bc plane.

In the title compound, C(10)H(16)O(6), the five-membered ring has an envelope conformation. The packing involves hydrogen-bonded carboxylic acid inversion dimers and three C-H⋯O inter-actions.

In 2',5'-dimethyl-p-terphenyl, C20H18, which displays pseudosymmetry (the true space group is Pna2(1), but less satisfactory refinement can also be achieved in Pbcn), the molecules are linked into chains by two short C-H...pi interactions to the centroid of the central ring. In 2',5'-bis(bromomethyl)-p-terphenyl, C20H16Br2, the polar CH2Br groups cause molecules to aggregate via C-H...Br and Br...Br interactions, forming a layer structure, in which the phenyl rings project outwards from the central, more polar, region.