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Propane-1,3-diaminium squarate dihydrate, C3H12N22+·C4O42−·2H2O, results from the proton-transfer reaction of propane-1,3-di amine with squaric acid and subsequent crystallization from aqueous medium. The title compound crystallizes in the tetragonal crystal system (space group P4bm) with Z = 2. The squarate dianion belongs to the point group D4h and contains a crystallographic fourfold axis. The propane-1,3-diaminium dication exhibits a C2v-symmetric all-anti conformation and resides on a special position with mm2 site symmetry. The orientation of the propane-1,3-diaminium ions makes the crystal structure polar in the c-axis direction. The solid-state supramolecular structure features a triperiodic network of strong hydrogen bonds of the N—H⋯O and O—H⋯O types. [ABSTRACT FROM AUTHOR]

In view of the rise of drug-resistant tuberculosis and difficult-to-treat related diseases caused by non-tuberculous mycobacteria, there is an urgent need for antimycobacterial drug discovery. Nα-aroyl-N-aryl-phenylalanine amides (AAPs) have been identified as antimycobacterial agents and are subject to lead optimization. The aim of the present study is to evaluate the impact of N-aryl ortho cyano substitution in a lead compound on the crystal and molecular structure and its in vitro activity against Mycobacterium abscessus. The title AAP can be conveniently synthesized from N-Boc-protected d-phenylalanine in two amide coupling steps using a previously established racemization-free method. Two polymorphic forms in the solid-state are described, as discovered by X-ray and electron diffraction. The introduction of a cyano group in the ortho position of the AAP N-aryl ring, however, leads to loss of in vitro activity against M. abscessus subsp. abscessus. [ABSTRACT FROM AUTHOR]

The title compound, 3‐[(benzo‐1,3‐dioxol‐5‐yl)amino]‐4‐methoxycyclobut‐3‐ene‐1,2‐dione, C12H9NO5 (3), is a precursor to an antimycobacterial squaramide. Block‐shaped crystals of a monoclinic form (3‐I, space group P21/c, Z = 8, Z′ = 2) and needle‐shaped crystals of a triclinic form (3‐II, space group P‐1, Z = 4, Z′ = 2) were found to crystallize concomitantly. In both crystal forms, R22(10) dimers assemble through N—H...O=C hydrogen bonds. These dimers are formed from crystallographically unique molecules in 3‐I, but exhibit crystallographic Ci symmetry in 3‐II. Twinning by pseudomerohedry was encountered in the crystals of 3‐II. The conformations of 3 in the solid forms 3‐I and 3‐II are different from one another but are similar for the unique molecules in each polymorph. Density functional theory (DFT) calculations on the free molecule of 3 indicate that a nearly planar conformation is preferred. [ABSTRACT FROM AUTHOR]

4-(4-nitrophenyl)thiomorpholine, the title compound, has been used as a precursor for the corresponding 4-thiomorpholinoaniline, which is a useful building block in medicinal chemistry. The crystal and molecular structures of the title compound, however, have not been described thus far. We synthesized the title compound by means of a nucleophilic aromatic substitution reaction of 4-fluoronitrobenzene and thiomorpholine and structurally characterized it by X-ray crystallography, DFT calculations, and Hirshfeld surface analysis. In the crystal, the molecule exhibits an approximately CS-symmetric structure, with the nitrogen-bound 4-nitrophenyl group in a quasi axial position on the six-membered thiomorpholine ring in a low-energy chair conformation. The solid-state structure of the title compound is markedly different from that of its morpholine analogue. This can be ascribed to the formation of centrosymmetric dimers through intermolecular C–H···O weak hydrogen bonds involving the methylene groups adjacent to the sulfur atom and face-to-face aromatic stacking. [ABSTRACT FROM AUTHOR]

Trehalose conjugates of 3-hydroxychromone (3HC) dyes have previously been utilized as fluorescence labels to detect metabolically active mycobacteria with a view to facilitating point-of-care detection of mycobacterial pathogens, especially Mycobacterium tuberculosis. We subjected the 3HC dye 2-(6-(diethylamino)benzofuran-2-yl)-3-hydroxy-4H-chromen-4-one (3HC-2) to a combined X-ray crystallography and density functional theory (DFT) study, and conducted preliminary fluorescence labelling experiments with the model organism Mycobacterium aurum. In the crystal, 3HC-2 exhibits an s-cis conformation of the chromone and the benzofuran moieties about the central C–C bond. According to DFT calculations, the s-cis conformer is about 1.8 kcal mol−1 lower in energy than the s-trans conformer. The solid-state supramolecular structure features hydrogen-bonded dimers and π...π stacking. Fluorescence microscopy revealed fluorescence of M. aurum cells treated with the dye trehalose conjugate 3HC-2-Tre in the GFP channel. It was concluded that s-cis is the preferred conformation of 3HC-2 and that the generally considered non-pathogenic M. aurum can be labelled with the fluorescence probe 3HC-2-Tre for convenient in vitro drug screening of new antimycobacterial agents. [ABSTRACT FROM AUTHOR]

C10H8Cl2N2S2Zn, monoclinic, C2/c (no. 15), a = 12.317(2) Å, b = 9.868(2) Å, c = 10.947(2) Å, β = 92.37(2)°, V = 1329.3 Å3, Z = 4, Rgt(F) = 0.036, wRref(F2) = 0.132, T = 110 K.

The synthesis of ethyl 2-[(4-methyl­pyridin-2-yl)amino)-4-(pyridin-2-yl)thia­zole- 5-carboxyl­ate via the Hantzsch reaction and partial in situ transesterification during recrystallization from methanol-d4 to the d3-methyl ester, resulting in the title solid solution, ethyl 2-[(4-methyl­pyridin-2-yl)amino)-4-(pyridin-2-yl)thia­zole-5-carboxyl­ate–d3-methyl 2-[(4-methyl­pyridin-2-yl)amino)-4-(pyridin-2-yl)thia­zole-5-carboxyl­ate (0.88/0.12), 0.88C17H16N4O2S·0.12C16D3H11N4O2S, is reported. The refined ratio of ethyl to d3-methyl ester in the crystal is 0.880 (6):0.120 (6). The pyridine ring is significantly twisted out of the plane of the approximately planar picoline thia­zole ester moiety. N—H...N hydrogen bonds between the secondary amino group and the pyridine nitro­gen atom of an adjacent symmetry-related mol­ecule link the mol­ecules into polymeric hydrogen-bonded zigzag tapes extending by glide symmetry in the [001] direction. There is structural evidence for intra­molecular NS chalcogen bonding and inter­molecular weak C—H...O hydrogen bonds between adjacent zigzag tapes. [ABSTRACT FROM AUTHOR]

The title compound, [HgI2(C10H8N2O2S2)]n, a one-dimensional coordination polymer with HgI2 units and 2,2′-di­thio­bis­(pyridine N-oxide) spacer ligands in an alternating fashion, forms helical chains running along the b axis in the crystal. Within a single coordination polymer strand, the axially chiral 2,2′-di­thio­bis­(pyridine N-oxide) ligands are homochiral, but the enanti­omeric conformation is present in adjacent strands. Within a coordination polymer strand, the iodido ligands point towards the centroids of the aromatic rings of the pyridine N-oxide moieties in the coordination sphere of HgII. Moreover, intra-strand C—HO and C—HI inter­actions, and inter-strand short SI and SO contacts are observed. [ABSTRACT FROM AUTHOR]

Porphyrin assemblies display interesting photophysical properties and a relatively high thermal stability. Moreover, meso-functionalized porphyrins with virtually fourfold symmetry can be relatively readily synthesized from pyrrole and the appropriate aldehyde. A number of metallo derivatives of 5,10,15,20-tetrakis(4-cyanophenyl)porphyrin, where the N atom of the linear cyano group can act both as a donor for coordination bonds or as an acceptor for hydrogen bonds, have been structurally characterized by single-crystal X-ray analysis. The supramolecular and structural chemistry of the corresponding 2- and 3-cyanophenyl isomers of the parent porphyrin, however, has remained largely unexplored. The crystal structure of [5,10,15,20-tetrakis(3-cyanophenyl)porphyrinato]copper(II) (CuTCNPP) nitrobenzene trisolvate, [Cu(C48H24N8)]·3C6H5NO2, has been determined at 80 K by synchrotron single-crystal X-ray diffraction. CuTCNPP exhibits a C2 h-symmetric ααββ conformation, despite an unsymmetrical crystal environment, and is situated on a crystallographic centre of symmetry. The CuII ion adopts a genuine square-planar coordination by the four pyrrole N atoms. The 24-membered porphyrin ring system shows no marked deviation from planarity. In the crystal, the CuTCNPP molecules and two nitrobenzene molecules are face-to-face stacked in an alternating fashion, resulting in corrugated layers. The remaining nitrobenzene guest molecule per CuTCNPP resides in the region between four neighbouring columnar stacks of CuTCNPP and sandwiched nitrobenzene molecules, and is disordered over four positions about a centre of symmetry. [ABSTRACT FROM AUTHOR]