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We leveraged the recent increase in synthetic accessibility of SF5 Cl and Ar-SF4 Cl compounds to combine chemistry of the SF5 and SF4 Ar groups with strain-release functionalization. By effectively adding SF5 and SF4 Ar radicals across [1.1.1]propellane, we accessed structurally unique bicyclopentanes, bearing two distinct elements of bioisosterism. Upon evaluating these "hybrid isostere" motifs in the solid state, we measured exceptionally short transannular distances; in one case, the distance rivals the shortest nonbonding C⋅⋅⋅C contact reported to date. This prompted SC-XRD and DFT analyses that support the notion that a donor-acceptor interaction involving the "wing" C-C bonds is playing an important role in stabilization. Thus, these heretofore unknown structures expand the palette for highly coveted three-dimensional fluorinated building blocks and provide insight to a more general effect observed in bicyclopentanes.

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]

Traditionally, the teaching role has been one of nurturing and developing students' potential. However, teachers' work today comprises a complex mix of various factors that include teaching; learning new information and skills; keeping abreast of technological innovations and dealing with students, parents and the community. These are demanding roles and there are growing concerns about teacher well-being and competence. In particular, teachers are experiencing increasing levels of attrition, stress and burnout. This study investigated the relationship between burnout and competence for a sample of mid-career teachers in primary and secondary schools in Queensland. The results break new ground in reporting a negative association between the MBI subscale Depersonalization and competence that may be attributed to a distancing mechanism in difficult human interactions. Overall, the findings of this study hold implications for teacher training courses and the well-being and competence of teachers.

This study investigated the impact that holding a second university degree has on levels of burnout that is reported by beginning teachers during their first year of employment. This research formed part of an ongoing investigation that aims to identify important elements relating to teacher well-being during the transition from university to a teaching career. One hundred and twenty three teachers responded to a mail survey six weeks after they commenced full-time teaching (T1) and again six months later (T2). On both occasions the survey included the Educators Survey version of the Maslach Burnout Inventory (MBI: Maslach, Jackson, & Leiter, 1996). Forty five percent of respondents indicated that they held a second university degree in addition to their Bachelor of Education qualification when they registered as a teacher. A between-subjects MANOVA indicated that there were no significant differences in burnout scores between those respondents holding an additional university degree and those who only held the Bachelor of associated with the manifestation of debilitating symptoms which, over time, lead to significant reductions in the health and well-being of individuals who experience this phenomenon (Cordes & Dougherty, 1993; Kahill, 1988). Thirdly, the detrimental impact that burnout has upon individual workers significantly Education degree at T1. However, at T2, a similar analysis indicated that the group of respondents with a second degree had significantly higher burnout levels on two of the three MBI dimensions. These results suggest systematic differences may exist between the two categories of graduates and that these differences may impact on the rate at which burnout develops during the first year of a teaching career.

This paper examines the decline of the fraternity of St. George in Nottingham between 1459 and 1546. It uses the guild's accounts in conjunction with Nottingham's rich surviving documentary materials to investigate the financial management of the fraternity by its officers. It argues that the officers were adept at negotiating shifting economic conditions by switching between various revenue streams. However, this adroit management did not stem the tide of membership decline. It discusses the role of religious reform in the guild's ultimate demise. It investigates why the decline in membership started long before any moves towards state-sponsored religious reform in the 1540s. It examines the impact of key individuals upon the guild's history. It argues that, for a more nuanced view of the decline of fraternal organizations in this period, a recognition of individuals' impact upon institutions needs to be incorporated into our understanding of institutions' influences upon the economy. [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]

The title compound, C15H15F3N2O3S, crystallizes in the monoclinic system, space group I2/a, with Z = 8. As expected, the nine-membered heterobicyclic system is virtually planar and the cyclo­hexyl group adopts a chair conformation. There is structural evidence for intra­molecular N—SO chalcogen bonding between the benziso­thia­zolinone S atom and one O atom of the nitro group, approximately aligned along the extension of the covalent N—S bond [N—SO = 162.7 (1)°]. In the crystal, the mol­ecules form centrosymmetric dimers through C—HO weak hydrogen bonding between a C—H group of the electron-deficient benzene ring and the benzo­thia­zolinone carbonyl O atom with an R²2(10) motif. In contrast to the previously described N-acyl 7-nitro-5-(tri­fluoro­meth­yl)benzo[d]iso­thia­zol-3(2H)-ones, the title N-cyclo­hexyl­methyl analogue does not inhibit growth of Mycobacterium aurum and Mycobacterium smegmatis in vitro. [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]