(2,4,6-Tri-tert-butylphenylimino)thioxo-and -selenoxophosphoranes. Synthesis and structural characterization

A series of stable imino(chalcogeno)phosphoranes R  P( X)  NAr, RPh, 2, 4, 6-Me₃C₆H₂, 2, 4, 6-i-Pr₃C₆H₂; Ar 2, 4, 6-t-Bu₃C₆H₂; X  S, Se ( 5bd, 6b,c ), has been prepared by the oxidation of λ³-imino-phosphines R  P  N  Ar ( 4b-d ) with sulfur and selenium. When P  (tert-butyl)iminophosphine, t-Bu  P  N-  Ar ( 4a ), was reacted with S₈ and Se_iv the corresponding oligomeric metaphosphonimidates 7, 8 were obtained. All new compounds are characterized by their NMR spectra. The constitution of the imino(thioxo)phosphorane 5d is proved by X-ray crystal structure determination.     

Bioactive Nitrosylated and Nitrated N-(2-hydroxyphenyl)acetamides and Derived Oligomers: An Alternative Pathway to 2-Amidophenol-Derived Phytotoxic Metabolites

Incubation of Aminobacter aminovorans, Paenibacillus polymyxa, and Arthrobacter MPI764 with the microbial 2-benzoxazolinone (BOA)-degradation-product 2-acetamido-phenol, produced from 2-aminophenol, led to the recently identified N-(2-hydroxy-5-nitrophenyl) acetamide, to the hitherto unknown N-(2-hydroxy-5-nitrosophenyl)acetamide, and to N-(2-hydroxy-3-nitrophenyl)acetamide. As an alternative to the formation of phenoxazinone derived from aminophenol, dimers- and trimers-transformation products have been found. Identification of the compounds was carried out by LC/HRMS and MS/MS and, for the new structure N-(2-hydroxy-5-nitrosophenyl)acetamide, additionally by 1D- and 2D-NMR. Incubation of microorganisms, such as the soil bacteria Pseudomonas laurentiana, Arthrobacter MPI763, the yeast Papiliotrema baii and Pantoea ananatis, and the plants Brassica oleracea var. gongylodes L. (kohlrabi) and Arabidopsis thaliana Col-0, with N-(2-hydroxy-5-nitrophenyl) acetamide, led to its glucoside derivative as a prominent detoxification product; in the case of Pantoea ananatis, this was together with the corresponding glucoside succinic acid ester. In contrast, Actinomucor elegans consortium synthesized 2-acetamido-4-nitrophenyl sulfate. 1 mM bioactive N-(2-hydroxy-5-nitrophenyl) acetamide elicits alterations in the Arabidopsis thaliana expression profile of several genes. The most responsive upregulated gene was pathogen-inducible terpene synthase TPS04. The bioactivity of the compound is rapidly annihilated by glucosylation.     

Tailoring Heterometallic Cluster Functional Building Blocks: Synthesis,Separation, Structural and DFT Studies of [Re6−xMoxSe8(CN)6]n−

Influence of the metal core composition and geometry on the structure, spectroscopic properties and redox potentials was investigated for the first time for heterometallic (Re/Mo)₆ octahedral clusters. The discrete anionic clusters [Re_6-xMo_xSe₈(CN)₆]ⁿ⁻ (x=2, 3; n=4, 5) were obtained as individual salts. Their isomeric composition and bond-length distribution were inspected using a combination of single-crystal X-ray structure analysis, NMR, EXAFS, and DFT calculations.     

Photonuclear production and radiochemical separation of medically relevant radionuclides: 67Cu

Journal of Radioanalytical and Nuclear Chemistry - Production of medical radionuclide 67Cu by the irradiation of Zn of natural isotopic composition by bremsstrahlung photons of maximum energy of...     

Characteristics of a High-Resolution Mass Spectrum of an Adduct of 2-(Diethylamino)Ethylthiol with a Dipeptide (Cys–Pro)

Journal of Analytical Chemistry -     

Thiourea assisted recyclization of 1-(chloromethyl)dihydroisoquinolines: a convenient route to β-(o-thiazolylaryl)ethylamines

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Nonsymmetric [Pt(C^N*N′^C′)] Complexes: Aggregation-Induced Emission in the Solid State and in Nanoparticles Tuned by Ligand Structure

Five square-planar [Pt(C^N*N′^C′)] complexes ( Pt1 – Pt5 ) with novel nonsymmetric tetradentate ligands ( L1 – L5 ) were synthesized and characterized. Varying the structure of the metalating aromatic systems result in substantial changes in photophysical properties and intermolecular interaction mode of the complexes in solution and in solid state. The complexes are strongly emissive in tetrahydrofuran solution, with the band maxima ranging from 560 to 690 nm. Three of these complexes ( Pt1 , Pt2 , Pt4 ) afford nanospecies upon injection of their solution into water, which show aggregation-induced emission (AIE) with a strong red shift of emission bands. In the solid state, crystalline samples of these complexes demonstrate mechanochromism upon grinding with a bathochromic shift of the emission. DFT and TD-DFT computational analysis of monomeric Pt1 – Pt5 in solution and model dimeric emitters formed through intermolecular interaction of Pt1 , Pt2 , Pt4 molecules allowed assignment of observed AIE to the ³MMLCT excited states of Pt-Pt bonded aggregates of these complexes.     

Influence of Spatial Losses of the Signal Detected by a Single-Pixel Detector on the Quality of Object Image Reconstruction

Radiophysics and Quantum Electronics - The reconstruction methods, which are based on compressed sensing (CS), make it possible to record and reconstruct information basing on its sparse or...     

Large-Scale Asymmetric Synthesis of Fmoc-(S)-2-Amino-6,6,6-Trifluorohexanoic Acid

Here we report the first large-scale synthesis of Fmoc-(S)-2-amino-6,6,6-trifluorohexanoic acid via asymmetric alkylation of chiral Ni(II)-complex of glycine Schiff base with CF₃(CH₂)₃I. The synthesis was performed on over 100 g scale and can be recommended as the most advanced procedure for reliable preparation of large amounts of enantiomerically pure Fmoc-(S)-2-amino-6,6,6-trifluorohexanoic acid for protein engineering and drug design. Chiral auxiliary used in this protocol can be >90 % recovered and reused.     

DFT and experimental study of triallylborane-mediated isomerization of α-allylated azaheterocycles

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