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Mol-ecules of the title compound, [Zn(8)(C(6)F(5))(8)O(4)(C(4)H(10)O)(4)], are located on a special position of site symmetry [Formula: see text]. As a result, there is just one quarter-mol-ecule in the asymmetric unit. The title compound features a Zn(4)O(4) cube. Each Zn atom in the cube carries a pentafluorophenyl substituent. Each O atom is bonded to a further Zn atom, which is connected to a pentafluorophenyl substituent and the O atom of a diethyl ether mol-ecule. All ether C atoms are disordered over two sets of sites with a site occupation factor of 0.51 (2) for the major occupied site.
In the title compound, C40H76Si, the Si atom is located on a special position of site symmetry -4. Thus, there is just a quarter of a molecule in the asymmetric unit. The C=C double bonds exhibit a trans configuration. The Si atom and the tert-butyl group are located on the same side of the plane formed by the C=C double bond and its four substituents. The crystal packing shows no short contacts between the molecules and despite the low crystal density (0.980 Mg m−3), there are no significant voids in the structure.
The crystal structure of the title salt, [Li(CH3CN)4][B(NCS)4], is composed of discrete cations and anions. Both the Li and B atoms show a tetrahedral coordination by four equal ligands. The acetonitrile and isothiocyanate ligands are linear. The bond angles at the B atom are close to the ideal tetrahedral value [108.92 (18)–109.94 (16)°], but the bond angles at the Li atom show larger deviations [106.15 (17)–113.70 (17)°].
The title compound, [Li4O4(C12H8BO)4(C4H10O)4], features a Li4O4 cube. Each Li atom in the cube is additionally coordinated by a diethyl ether molecule and each O atom in the cube carries a 9-oxa-10-boraanthracene residue. The crystal studied was a non-merohedral twin [twin law (-1 0 0 / 0 0 1 / 0 1 0); the contribution of the major twin component refined to 0.553 (3)] emulating apparent tetragonal symmetry, whereas the actual crystal system is just orthorhombic.
The title compound, [Tl4(C4H9O)4], featuring a (Tl—O)4 cube, crystallizes with a quarter-molecule (located on a special position of site symmetry An external file that holds a picture, illustration, etc. Object name is e-66-m1621-efi1.jpg..) and a half-molecule (located on a special position of site symmetry 23.) in the asymmetric unit. The Tl—O bond distances range from 2.463 (12) to 2.506 (12) Å. All O—Tl—O bond angles are smaller than 90° whereas the Tl—O—Tl angles are wider than a rectangular angle.
Synthesis and crystal structure of 2-(2-hydroxyphenyl)-1,3-bis(4-methoxybenzyl)-1,3-diazinan-5-ol
(2022)
The redetermined structure of 2-(2-hydroxyphenyl)-1,3-bis(4-methoxybenzyl)-1,3-diazinan-5-ol, C26H30N2O4, at 173 K has orthorhombic (Pbca) symmetry. It was previously described by Bolte et al. [ Private Communication (refcode EWICEV). CCDC, Cambridge, England]. The title compound resulted from the condensation reaction between 1,3-bis{[(4-methoxyphenyl)methyl]amino}propan-2-ol and 2-hydroxybenzaldehyde in CH3OH. The structure exhibits disorder. One of the 4-methoxybenzyl groups, the hydroxy group bonded to the 1,3-diazinan ring, and the methyl group of the methoxy residue are disordered over two orientations, with occupancies of 0.807 (3)/0.193 (3), 0.642 (5)/0.358 (5), and 0.82 (4)/0.18 (4), respectively. The dihedral angles between the mean planes of the central 1,3-diazinan-5-ol and the 4-methoxyphenyl rings (both occupancy components of the disordered ring) are 88.65 (13), 85.79 (14) and 83.4 (7)°. The crystal packing is sustained by C—H...O and O—H...π interactions, giving rise to infinite chains running along the b-axis direction.
The title thiourea was synthesized by reaction of 3,4,5-trimethoxybenzoyl isothiocyante with 3-fluoroaniline. The 3,4,5-trimethoxybenzoyl isothiocyante was produced in situ by reaction of 3,4,5-trimethoxybenzoyl chloride with ammonium thiocyanate in dry acetonitrile. The structure was confirmed by the spectroscopic, elemental analysis and single crystal X-ray diffraction data. It crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 13.0966(9), b = 16.6460(13), c = 7.8448(5), β = 106.721(5)°, V 1637.9(2) ų, Z = 4.
The respiratory chain of Escherichia coli contains two different types of terminal oxidase that are differentially regulated as a response to changing environmental conditions. These oxidoreductases catalyze the reduction of molecular oxygen to water and contribute to the proton motive force. The cytochrome bo3 oxidase (cyt bo3) acts as the primary terminal oxidase under atmospheric oxygen levels, whereas the bd‐type oxidase is most abundant under microaerobic conditions. In E. coli, both types of respiratory terminal oxidase (HCO and bd‐type) use ubiquinol‐8 as electron donor. Here, we assess the inhibitory potential of newly designed and synthesized 3‐alkylated Lawson derivatives through L‐proline‐catalyzed three‐component reductive alkylation (TCRA). The inhibitory effects of these Lawson derivatives on the terminal oxidases of E. coli (cyt bo3 and cyt bd‐I) were tested potentiometrically. Four compounds were able to reduce the oxidoreductase activity of cyt bo3 by more than 50 % without affecting the cyt bd‐I activity. Moreover, two inhibitors for both cyt bo3 and cyt bd‐I oxidase could be identified. Based on molecular‐docking simulations, we propose binding modes of the new Lawson inhibitors. The molecular fragment benzyl enhances the inhibitory potential and selectivity for cyt bo3, whereas heterocycles reduce this effect. This work extends the library of 3‐alkylated Lawson derivatives as selective inhibitors for respiratory oxidases and provides molecular probes for detailed investigations of the mechanisms of respiratory‐chain enzymes of E. coli.
To examine their luminescence behavior, two air-stable BN addition compounds were synthesized by the reaction of 5-fluoro-2-(2′-pyridyl)indole with 1,4- and 1,3-bis(bromo(methyl)boryl)benzene, respectively. Both BN adducts are luminescent. Their emission maxima (1,3-substituted BN adduct: 495 nm; 1,4-substituted BN adduct: 497 nm) are comparable with the value (490 nm) of the related mono-borylated benzene species, which is composed of a BPh2 fragment and a 5-fluoro-2-(2′-pyridyl) indole unit. The starting materials 1,4- and 1,3-bis(bromo(methyl)boryl)benzene were accessible by treatment of 1,4- or 1,3-bis(dibromoboryl)benzene with two equivalents of SnMe4. In addition, the results of the X-ray structure analyses of the B,B′-bis-5-fluoro-2-(2′-pyridyl)indolyl-complexed meta-bismethylborylbenzene fragment (9, triclinic, P1̅) as well as of 5-chloro-2-(2′-pyridyl)indole (2, monoclinic, P21/c) and 5-fluoro-2-(2′-pyridyl)indole (1, orthorhombic, Pca21) are reported. The pyridylindole derivatives of this approach were synthesized by an optimized two-step procedure from 2-acetylpyridine and 4-fluoro- or 4-chlorophenylhydrazine hydrochloride.