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1.
IUCrdata ; 9(Pt 4): x240345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38721002

RESUMO

In the title compound, {(C6H8N)[Zn2(HPO3)2(H2PO3)]}n, the constituent ZnO4, HPO3 and H2PO3 polyhedra of the inorganic component are linked into (010) sheets by Zn-O-P bonds (mean angle = 134.4°) and the layers are reinforced by O-H⋯O hydrogen bonds. The protonated templates are anchored to the inorganic sheets via bifurcated N-H⋯(O,O) hydrogen bonds.

2.
Int J Mol Sci ; 25(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38673898

RESUMO

The absolute configuration and stability of two thianthrene chiral sulfoxides has been determined by means of X-ray single-crystal structure determinations. The analyses and configurations allow verification that the diastereomeric sulfoxides are stable in solution and are not interconverting, which has been suggested in some studies of sulfoxides. The two thianthrene sulfoxides have slightly different Rf values, which allowed their separation using flash chromatography on silica. The spots run back-to-back, which posed a challenge for their separation. The pure, separated compounds in solution remain as separate, single spots on a Thin Layer Chromatography (TLC) plate.


Assuntos
Sulfóxidos , Estereoisomerismo , Sulfóxidos/química , Cristalografia por Raios X/métodos , Modelos Moleculares , Cromatografia em Camada Fina/métodos , Fenantrenos/química , Estrutura Molecular
3.
ACS Omega ; 8(46): 44163-44171, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38027375

RESUMO

The reaction of either 2-aminophenol or 2-(N-methylamino)phenol with 1,2-difluoro-4,5-dinitrobenzene and sodium carbonate in EtOH gives 2,3-dinitrophenoxazines. One nitro group, conjugated to the aryl ether, was displaced from 2,3-dinitro-10-methylphenoxazine with different nucleophiles: BuNH2, KOEt, and KOH. The reaction of 2-aminothiophenol with 1,2-difluoro-4,5-dinitrobenzene under the same conditions gives 2,3-dinitrophenothiazine. This reacted with BuNH2 forming 2-butylamino-3-nitrophenothiazine. The dihedral angles of the different compounds are compared.

4.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834130

RESUMO

A porous structure formed from sheets with cavities and two close packed structures were crystallised from building blocks prepared from 2,4-difluoronitrobenzene, a diamine linker and n-butylamine. The porous structure crystallised from a flexible building block prepared using 1,4-diaminobutane as linker. The close packed structures were prepared using either piperazine or 1,4-bis(aminomethyl)benzene as a linker and have less conformational freedom.


Assuntos
Porosidade , Conformação Molecular
6.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 4): 272-279, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057029

RESUMO

The syntheses and crystal structures of four hydro-thermally prepared organo-zinc phosphites, viz. poly[[(2-amino-3-methyl-pyridine)-µ3-phospho-nato-zinc] hemihydrate], {[Zn(HPO3)(C6H8N2)]·0.5H2O} n , (I), poly[(2-amino-4-methyl-pyridine)-µ3-phospho-nato-zinc], [Zn(HPO3)(C6H8N2)] n , (II), poly[(2-amino-5-methyl-pyridine)-µ3-phospho-nato-zinc], [Zn(HPO3)(C6H8N2)] n , (III), and poly[bis-(2-amino-4-methyl-pyridinium) [tetra-µ3-phospho-nato-trizinc] monohydrate], {(C6H9N2)2[Zn3(HPO3)4]·H2O} n , (IV), are described. Compounds (I)-(III) are constructed from vertex-sharing ZnO3N tetra-hedra (the organic mol-ecule acting as a ligand) and HPO3 pseudo pyramids in a 1:1 ratio to generate the same motif of infinite 4-ring 'ladder' chains propagating in the [010], [101] and [100] directions, respectively, whereas (IV) consists of (010) layers of vertex-sharing ZnO4 and HPO3 units in a 3:4 ratio with the protonated organic mol-ecule acting as a template. When an excess of HCl is used in the synthesis, the simple hydrated mol-ecular salt, bis-(2-amino-3-methyl-pyridinium) tetra-chloro-zincate monohydrate, (C6H8N2)2[ZnCl4]·H2O, (V), arises. Com-pounds (I)-(V) feature extensive networks of hydrogen bonds, both classical (N-H⋯O, N-H⋯Cl, O-H⋯O) and non-classical (C-H⋯O, C-H⋯Cl) in nature, which help to consolidate the extended structures.

7.
ChemistryOpen ; 12(2): e202300007, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36782392

RESUMO

Oxidative condensation of three p-phenylenediamines with 3-hydroxy-2-methyl-N-(phenylamino)benzene gives new coloured aposafranones. 2-Methylresorcinol is easy to convert into the asymmetric building block 3-hydroxy-2-methyl-N-(phenylamino)benzene with aniline. The aposafranones are sterically crowded because of the 1-methyl and N-phenyl groups. The UV/Vis absorption maxima are in the range 530-545 nm.

8.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 6): 619-624, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36072151

RESUMO

The crystal structures of four thio-phene-carbohydrazide-pyridine derivatives, viz. N'-[(E)-pyridin-3-yl-methyl-idene]thio-phene-2-carbohydrazide, C11H9N3OS, (I), N'-[(E)-pyridin-2-yl-methyl-idene]thio-phene-2-carbohydrazide, C11H9N3OS, (II), N-methyl-N'-[(E)-pyridin-2-yl-methyl-idene]thio-phene-2-carbohydrazide, C12H11N3OS, (III) and N'-[(E)-pyridin-2-yl-methyl-idene]-2-(thio-phen-2-yl)ethano-hydrazide, C12H11N3OS, (IV) are described. The dihedral angles between the thio-phene ring and the pyridine ring are 21.4 (2), 15.42 (14), 4.97 (8) and 83.52 (13)° for (I)-(IV), respectively. The thio-phene ring in (IV) is disordered over two orientations in a 0.851 (2):0.149 (2) ratio. Key features of the packing include N-H⋯Np (p = pyridine) hydrogen bonds in (I), which generate C(7) chains propagating in the [001] direction; N-H⋯Np links also feature in (II), but in this case they lead to C(6) [001] chains; in (IV), classical amide (C4) N-H⋯O links result in [010] chains; in every case adjacent mol-ecules in the chains are related by 21 screw axes. There are no classical hydrogen bonds in the extended structure of (III). Various weak C-H⋯X (X = O, N, S) inter-actions occur in each structure, but no aromatic π-π stacking is evident. The Hirshfeld surfaces and fingerprint plots for (I)-(IV) are compared.

9.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 7): 737-741, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35855358

RESUMO

The isostructural compounds caesium deca-sodium tetra-zirconium nona-arsenate, CsNa10Zr4(AsO4)9, and caesium deca-sodium tetra-hafnium nona-arsenate, CsNa10Hf4(AsO4)9, arose as unexpected single-crystal products from the reactions of Na2CO3, MO2 (M = Zr, Hf) and As2O5 in a eutectic flux of NaCl and CsCl. They consist of MO6 octa-hedra and AsO4 tetra-hedra sharing vertices to generate three-dimensional polyhedral networks encapsulating the caesium and sodium ions. The MO6 groups share all their vertices with adjacent As atoms but the As atoms have one or two 'terminal' O atoms not bonded to Zr or Hf. The Cs+ ion adopts a squashed octa-hedral geometry and the coordination polyhedra of the partially occupied sodium ions are variously trigonal bipyramidal, tetra-hedral, square pyramidal and trigonal pyramidal. Site symmetries: Cs ; M 3; As 1 and 2; O 1; Na 1, 2 and 3. The M = Zr crystal was refined as an obverse/reverse rhombohedral twin.

10.
ChemistryOpen ; 11(6): e202200092, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35674450

RESUMO

Studies have been performed aimed at the synthesis of N-heteroacenes via substitution reactions of 4,5-difluoro-1,2-dinitrobenzene with a diamine. The fluorine atoms are displaced first, followed by an activated nitro group. Two intermediates have been characterised by X-ray single-crystal structure determinations. Their intermolecular interactions were examined by Hirshfeld surfaces to assess their suitability for organic molecular electronics. The high reactivity of the phenazine, which is prone to oxidise and rearrange, as are displacement products prepared from it, is explained by the formation of a cis-aci-nitro form from the secondary amine of the phenazine and a nitro group.


Assuntos
Diaminas , Flúor , Cristalografia por Raios X , Diaminas/química , Flúor/química , Estrutura Molecular , Fenazinas
11.
ChemistryOpen ; 11(3): e202100150, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34432942

RESUMO

A new method for the synthesis of substituted 1,4-dihydrophenazines is reported and the structure of N-butyl-5-methyl-3-nitro-5,10-dihydrophenazine is proven by an X-ray single-crystal structure determination.

12.
Radiat Res ; 197(3): 0, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724704

RESUMO

Delayed radiation myelopathy is a rare, but significant late side effect from radiation therapy that can lead to paralysis. The cellular and molecular mechanisms leading to delayed radiation myelopathy are not completely understood but may be a consequence of damage to oligodendrocyte progenitor cells and vascular endothelial cells. Here, we aimed to determine the contribution of endothelial cell damage to the development of radiation-induced spinal cord injury using a genetically defined mouse model in which endothelial cells are sensitized to radiation due to loss of the tumor suppressor p53. Tie2Cre; p53FL/+ and Tie2Cre; p53FL/- mice, which lack one and both alleles of p53 in endothelial cells, respectively, were treated with focal irradiation that specifically targeted the lumbosacral region of the spinal cord. The development of hindlimb paralysis was followed for up to 18 weeks after either a 26.7 Gy or 28.4 Gy dose of radiation. During 18 weeks of follow-up, 83% and 100% of Tie2Cre; p53FL/- mice developed hindlimb paralysis after 26.7 and 28.4 Gy, respectively. In contrast, during this period only 8% of Tie2Cre; p53FL/+ mice exhibited paralysis after 28.4 Gy. In addition, 8 weeks after 28.4 Gy the irradiated spinal cord from Tie2Cre; p53FL/- mice showed a significantly higher fractional area positive for the neurological injury marker glial fibrillary acidic protein (GFAP) compared with the irradiated spinal cord from Tie2Cre; p53FL/+ mice. Together, our findings show that deletion of p53 in endothelial cells sensitizes mice to the development of delayed radiation myelopathy indicating that endothelial cells are a critical cellular target of radiation that regulates myelopathy.


Assuntos
Traumatismos da Medula Espinal/radioterapia , Animais , Relação Dose-Resposta à Radiação , Células Endoteliais , Feminino , Proteína Glial Fibrilar Ácida/efeitos da radiação , Humanos , Masculino , Camundongos , Lesões Experimentais por Radiação , Radiação Ionizante , Medula Espinal/efeitos dos fármacos , Fatores de Tempo , Proteína Supressora de Tumor p53/efeitos da radiação
13.
Molecules ; 26(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34500794

RESUMO

In this study, treatment of anhydrous trazodone powder with ammonium carbamate in warm water crystallised two new polymorphs or dihydrates of trazodone after 5 h, whose structures were determined by X-ray single crystal diffraction. Each dihydrate contains infinite zigzag hydrogen-bonded chains of water molecules, which are stabilised by the N4 acceptor atom of the piperazine ring and the pendant carbonyl O1 atom of the triazole ring, as well as other water molecules. The strong dipole moment expected for the O1 atom makes it a good hydrogen bond acceptor for stabilising the chains of water molecules. Each molecule of trazodone has a similar conformation in both hydrates, except for the propyl chains, which adopt different conformations: anti-gauche in the ß hydrate (triazole N-C-C-C and C-C-C-piperazine N) and anti-anti in the γ hydrate. Both piperazine rings adopt chair conformations, and the exocyclic N-C bonds are in equatorial orientations. The Hirshfeld surfaces and two-dimensional fingerprint plots for the polymorphs were calculated using CrystalExplorer17, which indicated contacts significantly shorter than the sum of the van der Waals radii in the vicinity of the piperazine N4 and triazole O1 atoms corresponding to the strong hydrogen bonds accepted by these atoms.

16.
Phys Chem Chem Phys ; 23(22): 12600-12611, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34047739

RESUMO

A number of liquid crystal dimers have been synthesised and characterised containing secondary or tertiary (N-methyl) benzanilide-based mesogenic groups. The secondary amides all form nematic phases, and we present the first example of an amide to show the twist-bend nematic (NTB) phase. Only two of the corresponding N-methylated dimers formed a nematic phase and with greatly reduced nematic-isotropic transition temperatures. Characterisation using 2D ROESY NMR experiments, DFT geometry optimisation and X-ray diffraction reveal that there is a change in the preferred conformation of the benzanilide core on methylation, from Z to E. The rotational barrier around the N-C(O) bond has been measured using variable temperature 1H NMR spectroscopy. This dramatic change in shape accounts for the remarkable difference in liquid crystalline behaviour between these secondary and tertiary amide-based materials.

17.
Am J Forensic Med Pathol ; 42(2): 174-177, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33590987

RESUMO

ABSTRACT: Acute myeloid leukemia can rarely cause sudden, unexpected death in children. Presentation may be non-specific and death may occur in children with no prior medical history. Herein we present the case of a previously healthy 2-year and 2 month-old White girl, who on autopsy, was found to have acute myeloid leukemia with KMT2A rearrangement extensively involving all major thoracic and abdominal organs. This case is presented to the forensic community to discuss the presentation and findings in sudden death caused by acute leukemia. The case highlights when acute leukemia should enter the differential as a potential cause of death, as well as potential resources available in the postmortem workup of acute leukemias.


Assuntos
Morte Súbita/etiologia , Leucemia Mieloide Aguda/diagnóstico , Acidose/etiologia , Anemia/etiologia , Pré-Escolar , Feminino , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Humanos , Hiperpotassemia/etiologia , Hipoglicemia/etiologia , Ácido Láctico/sangue , Leucemia Mieloide Aguda/complicações , Leucocitose/etiologia , Proteína de Leucina Linfoide-Mieloide/genética , Trombocitopenia/etiologia
19.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 6): 909-913, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32523762

RESUMO

The hydro-thermal synthesis and crystal structure of the title two-dimensional coordination polymer, poly[bis-(µ3-3,4-di-amino-benzoato-κ3 N 3,O,O')manganese(II)], [Mn(C7H7N2O2)2] n , are described. The Mn2+ cation (site symmetry ) adopts a tetra-gonally elongated trans-MnN2O4 octa-hedral coordination geometry and the µ3-N,O,O' ligand (bonding from both carboxyl-ate O atoms and the meta-N atom) links the metal ions into infinite (10) layers. The packing is consolidated by intra-layer N-H⋯O and inter-layer N-H⋯N hydrogen bonds. The structure of the title compound is compared with other complexes containing the C7H7N2O2 - anion and those of the related M(C8H8NO2)2 (M = Mn, Co, Ni, Zn) family, where C8H8NO2 - is the 3-amino-4-methyl-benzoate anion.

20.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 4): 527-533, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32280498

RESUMO

The syntheses and crystal structures of three mol-ecular salts of protonated 3,4-di-amino-benzoic acid, viz. 2-amino-5-carb-oxy-anilinium chloride, C7H9N2O2 +·Cl-, (I), 2-amino-5-carb-oxy-anilinium bromide, C7H9N2O2 +·Br-, (II), and 2-amino-5-carb-oxy-anilinium nitrate monohydrate, C7H9N2O2 +·NO3 -·H2O, (III), are described. The cation is protonated at the meta-N atom (with respect to the carb-oxy group) in each case. In the crystal of (I), carb-oxy-lic acid inversion dimers linked by pairwise O-H⋯O hydrogen bonds are seen and each N-H group forms a hydrogen bond to a chloride ion to result in (100) undulating layers of chloride ions bridged by the inversion dimers into a three-dimensional network. The extended structure of (II) features O-H⋯Br, N-H⋯Br and N-H⋯O hydrogen bonds: the last of these generates C(7) chains of cations. Overall, the packing in (II) features undulating (100) sheets of bromide ions alternating with the organic cations. Inter-molecular inter-actions in the crystal of (III) include O-H⋯O, O-H⋯(O,O), N-H⋯O, N-H⋯N and O-H⋯N links. The cations are linked into (001) sheets, and the nitrate ions and water mol-ecules form undulating chains. Taken together, alternating (001) slabs of organic cations plus anions/water mol-ecules result. Hirshfeld surfaces and fingerprint plots were generated to give further insight into the inter-molecular inter-actions in these structures. The crystal used for the data collection of (II) was twinned by rotation about [100] in reciprocal space in a 0.4896 (15):0.5104 (15) ratio.

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