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Luminescence is observed in three novel macropolyhedral nineteen- and eighteen-vertex chalcogenaboranes: Se 2 B 17 H 17 (1), SeB 17 H 19 (3) and SeB 18 H 20 (4). This led us to the recognition that previously published macropolyhedral heteroborane species might also exhibit luminescence. Thus, the known nineteen- and eighteen-vertex dithiaboranes S 2 B 17 H 17 (2), n-S 2 B 16 H 16 (5) and i-S 2 B 16 H 16 (6) were synthesised and also found to exhibit a range of luminescent properties. These macropolyhedral species are very different from the previously unique fluorescent binary borane B 18 H 22 in terms of their structural architectures, by the presence of borane cluster hetero atoms, and, as in the cases of 5 and 6, that their synthetic origins are not derived simply through the modification of B 18 H 22 itself. They consequently greatly expand the possibilities of finding new luminescent inorganic borane species., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The chemistry and physics of macropolyhedral B 18 H 22 clusters have attracted significant attention due to the interesting photophysical properties of anti -B 18 H 22 (blue emission, laser properties) and related potential applications. We have focused our attention on the "forgotten" syn -B 18 H 22 isomer, which has received very little attention since its discovery compared to its anti -B 18 H 22 isomer, presumably because numerous studies have reported this isomer as nonluminescent. In our study, we show that in crystalline form, syn -B 18 H 22 exhibits blue fluorescence and becomes phosphorescent when substituted at various positions on the cluster, associated with peculiar microstructural-dependent effects. This work is a combined theoretical and experimental investigation that includes the synthesis, separation, structural characterization, and first elucidation of the photophysical properties of three different monothiol-substituted cluster isomers, [1-HS- syn -B 18 H 21 ] 1 , [3-HS- syn -B 18 H 21 ] 3 , and [4-HS- syn -B 18 H 21 ] 4 , of which isomers 1 and 4 have been proved to exist in two different polymorphic forms. All of these newly substituted macropolyhedral cluster derivatives ( 1 , 3 , and 4 ) have been fully characterized by NMR spectroscopy, mass spectrometry, single-crystal X-ray diffraction, IR spectroscopy, and luminescence spectroscopy. This study also presents the first report on the mechanochromic shift in the luminescence of a borane cluster and generally enriches the area of rather rare boron-based luminescent materials. In addition, we present the first results proving that they are useful constituents of carbon-free self-assembled monolayers.

The title Schiff base compounds, C 22 H 26 N 4 O ( I ) and C 18 H 16 FN 3 O ( II ), were each synthesized by a single-step condensation reaction. The substituted benzyl-idene ring is inclined to the pyrazole ring mean planes by 22.92 (7)° in I and 12.70 (9)° in II . The phenyl ring of the 4-amino-anti-pyrine unit is inclined to the pyrazole ring mean plane by 54.87 (7)° in I and by 60.44 (8)° in II . In the crystal of I , the mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions to form layers lying parallel to (001). In the crystal of II , the mol-ecules are linked by C-H⋯O and C-H⋯F hydrogen bonds and C-H⋯π inter-actions, thereby forming layers lying parallel to (010). Hirshfeld surface analysis was employed to further qu-antify the inter-atomic inter-actions in the crystals of both compounds., (© Shankar et al. 2023.)

A single-crystal structure determination of the cubic phase of CsNO 3 based on data collected at 439 K up to sinθ max /λ = 0.995000 Å -1 , i.e. to an unprecedentedly high-θ value, is reported. The structure has been refined in Pm3m (Z = 1). Analysis of the difference electron-density maps revealed that the most appropriate model is the twelve-orientation model with the Cs, N, O1 and O2 atoms situated on the Wyckoff positions 1a, 6f, 6f and 24l, respectively, rather than the eight-orientation aragonite model with the Cs, N and O atoms situated on the Wyckoff positions 1a, 8g and 24m, respectively. Both models, however, show close similarities if the large anisotropic displacement parameters of the O atoms in the eight-orientation aragonite model are taken into account. The reason for this is shown to lie in the smeared electron density around the positions of the disordered [NO 3 ] - anion.

The conformational flexibilities are studied in two new organotin(IV) complexes, namely, trans-dichloridodimethylbis[N,N',N''-tris(2-chlorobenzyl)phosphoric triamide]tin(IV), [Sn(CH 3 ) 2 (C 21 H 21 Cl 3 N 3 OP) 2 Cl 2 ] or Sn(CH 3 ) 2 Cl 2 {OP[NHCH 2 C 6 H 4 (2-Cl)] 3 } 2 , (I), and bis(dipropylammonium) tetrachloridodimethylstannate(IV), [(CH 3 CH 2 CH 2 ) 2 NH 2 ] 2 [Sn(CH 3 ) 2 Cl 4 ], (II), and their analogous structures from the Cambridge Structural Database (CSD). The conformations are considered based on the N-P=O-Sn torsion angles for (I) and the C-C-C-N, C-C-N-C, C-N-C-C and N-C-C-C torsion angles for the two symmetry-independent [CH 3 CH 2 CH 2 NH 2 CH 2 CH 2 CH 3 ] + cations in (II), and the ±ac±sp±ac (ac = anticlinal and sp = synperiplanar) and ±ap±ap±ap±ap (ap = antiperiplanar) conformations are observed, respectively. In both structures, the four atoms in the corners of the square-planar segment of the octahedral shape around the Sn atom participate in normal hydrogen-bonding interactions as acceptors, which include two O and two Cl atoms for (I), and four Cl atoms for (II). However, the phosphoric triamide ligands block the environment around the Sn atom and limit the hydrogen-bond pattern to form a supramolecular ribbon assembly, while in the presence of small organic cations in (II), a two-dimensional hydrogen-bonded architecture is achieved. The weak interactions π-π, C-H...π and C-Cl...π in (I), and C-H...Cl in (II) do not change the dimensionality of the hydrogen-bond pattern. The 62 CSD structures analogous to (I), i.e. with an SnOPN 3 segment (including 83 entries) fall into four categories of conformations based on the N-P=O-Sn torsion angles. The 132 [(CH 3 CH 2 CH 2 ) 2 NH 2 ] + cations from 85 CSD structures are classified into seven groups based on the torsion angles noted for (II). Most of the CSD structures adopt the same associated conformations noted for (I) and (II). 15 [Sn(CH 3 ) 2 Cl 4 ] 2- anions extracted from the CSD are compared with the structure of (II).

Two new N-oxide compounds, namely glycinium 2-carboxy-1-(λ 1 -oxidaneyl)-1λ 4 -pyridine-6-carboxylate-glycine-water (1/1/1), C 2 H 6 NO 2 + ·C 7 H 4 NO 5 - ·C 2 H 5 NO 2 ·H 2 O or [(2,6-HpydcO)(HGLY)(GLY)(H 2 O)], 1, and methyl 6-carboxy-1-(λ 1 -oxidaneyl)-1λ 4 -pyridine-2-carboxylate, C 8 H 7 NO 5 or 2,6-HMepydcO, 2, were prepared and identified by elemental analysis, FT-IR, Raman spectroscopy and single-crystal X-ray diffraction. The X-ray analysis of 1 revealed an ionic compound containing a 2,6-HpydcO - anion, a glycinium cation, a neutral glycine molecule and a water molecule. Compound 2 is a neutral compound with two independent units in its crystal structure. In addition to the hydrogen bonds, the crystal network is stabilized by π-π stacking interactions of the types pyridine-carboxylate and carboxylate-carboxylate. The thermodynamic stability and charge-distribution patterns for isolated molecules of 2,6-H 2 pydcO and 2,6-HMepydcO, and their two similar derivatives, pyridine-2,6-dicarboxylic acid (2,6-H 2 pydc) and dimethyl 1-(λ 1 -oxidaneyl)-1λ 4 -pyridine-2,6-dicarboxylate (2,6-Me 2 pydcO), were studied by density functional theory (DFT) and natural bond orbital (NBO) analysis, respectively. The ability of these compounds and their analogues to interact with nine selected biomacromolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS and Top II) was investigated using docking calculations.

We report a complex study on the crystal structures, electronic properties, reactivity and dynamics of three polyoxometalate compounds (C6NH8)4[H2P2Mo5O23]·5H2O (1), (C2H8N)5[HP2Mo5O23]·(C3H9NO2)0.5·(H2O)1.5 (2) and (C2H8N)3[PMo12O40]·(H2O)0.34 (3). These compounds were synthesized using a solution method and characterized by single-crystal X-ray diffraction. Crystallography confirmed three distinct symmetries P1[combining macron], P21/c and R3[combining macron]c for 1, 2, and 3, respectively, and unit cell constants a = 12.5609(2) Å, b = 13.2470(2) Å, c = 14.0353(2) Å, α = 107.1568(14)°, β = 101.2854(13)°, γ = 92.1445(14)° for 1, a = 15.8583(6) Å, b = 17.3578(5) Å, c = 14.8499 (4) Å, β = 114.933(3)° for 2, and a = 16.3798(3) Å, c = 50.2781(5) Å for 3. Semi-empirical calculations applied on the compounds provided information about their reactivity and electronic structures. In this context, several discussions concerning the frontier molecular orbitals, molecular electrostatic potential, thermodynamic properties and local ionization potential were mentioned. We also conducted molecular dynamics analysis in order to elucidate the dynamics of cations and anions and their energy variation.

Thrombophilia is a risk factor for thrombosis. The hematologists have come under pressure to initiate thrombophilia testing on an increasing number of patients. This article summarized practical aspects, with focus on whom to test, why to test, what to test, what not to test and clinical management consequences for individuals having been identified with a thrombophilia.Key words: thrombophilia - thrombosis.

Hirshfeld surfaces and two-dimensional fingerprint plots are used to analyse the intermolecular interactions in two new phosphorothioic triamide structures, namely N,N',N''-tris(3,4-dimethylphenyl)phosphorothioic triamide acetonitrile hemisolvate, P(S)[NHC6H3-3,4-(CH3)2]3·0.5CH3CN or C24H30N3PS·0.5CH3CN, (I), and N,N',N''-tris(4-methylphenyl)phosphorothioic triamide-3-methylpiperidinium chloride (1/1), P(S)[NHC6H4(4-CH3)]3·[3-CH3-C5H9NH2](+)·Cl(-) or C21H24N3PS·C6H14N(+)·Cl(-), (II). The asymmetric unit of (I) consists of two independent phosphorothioic triamide molecules and one acetonitrile solvent molecule, whereas for (II), the asymmetric unit is composed of three components (molecule, cation and anion). In the structure of (I), the different components are organized into a six-molecule aggregate through N-H···S and N-H···N hydrogen bonds. The components of (II) are aggregated into a two-dimensional array through N-H···S and N-H···Cl hydrogen bonds. Moreover, interesting features of packing arise in this structure due to the presence of a double hydrogen-bond acceptor (the S atom of the phosphorothioic triamide molecule) and of a double hydrogen-bond donor (the N-H unit of the cation). For both (I) and (II), the full fingerprint plot of each component is asymmetric as a consequence of the presence of three fragments. These analyses reveal that H···H interactions [67.7 and 64.3% for the two symmetry-independent phosphorothioic triamide molecules of (I), 30.7% for the acetonitrile solvent of (I), 63.8% in the phosphorothioic triamide molecule of (II) and 62.9% in the 3-methylpiperidinium cation of (II)] outnumber the other contacts for all the components in both structures, except for the chloride anion of (II), which only receives the Cl···H contact. The phosphorothioic triamide molecules of both structures include unsaturated C atoms, thus presenting C···H/H···C interactions: 17.6 and 21% for the two symmetry-independent phosphorothioic triamide molecules in (I), and 22.7% for the phosphorothioic triamide molecule of (II). Furthermore, the N-H···S hydrogen bonds in both (I) and (II), and the N-H...Cl hydrogen bonds in (II), are the most prominent interactions, appearing as large red spots on the Hirshfeld surface maps. The N···H/H···N contacts in structure (I) are considerable, whereas for (II), they give a negligible contribution to the total interactions in the system.