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Moumita Maiti Kaustab Ghosh Tania M. Mendonça Thierry Stora Susanta Lahiri 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):1003-1011
This is the first report on the inventory of radionuclides produced in 1.4 GeV proton induced reaction on Lead–Bismuth Eutectic (LBE) targets. LBE targets of 6 mm diameter and 1 to 8 mm lengths were irradiated with 1.4 GeV protons. The radionuclides ranging from 7Be (53.12 days) to 207Po (5.8 h) were identified in the samples with the help of time resolved γ-ray spectroscopy. However, there is no signature of formation of At radioisotopes, which can be produced by the interaction of secondary particles, typical for thick targets. 相似文献
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Pabitra Kumar Kalita Susanta Kumar Borthakur Runumi Das Chandan Jyoti Choudhury 《合成通讯》2013,43(21):2444-2453
This paper describes a general method for the synthesis of homoallylic alcohols and amines by nucleophilic addition reaction of allyltributylstannane to carbonyl compounds and aldimines where iodine acts as a catalyst in H2O/acetic acid (1:1) medium. Only 10 mol% of I2 is required for various organic transformations. By using this process, various homoallylic alcohols and amines are produced in good to excellent yields. 相似文献
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Supriti Sen Snehasis Banerjee Susanta S. Adhikari Anuradha Moirangthem Anupam Basu 《合成通讯》2014,44(6):847-857
A systematic study of the reaction of 1,4-dihydrazinophthalazine (DHPH) with 1,3-dicarbonyls [viz., acetylacetone (acac), dibenzoylmethane (bzbz), and 1-benzoylacetone (bzac)] varying the reaction conditions was carried out to obtain the phthalazine derivatives (1–4). One-pot reaction of DHPH with acac led to the formation of two compounds 1 and 2, with various factors such as the presence of the acid or base, amount of the acac, time of reflux, and the temperature. The reaction conditions of DHPH with bzbz or bzac are sort of different to isolate the products 3 and 4, respectively. The derivatives (1–4) have been characterized by elemental analyses, 1H NMR, and electrospray ionization–mass spectrometry (ESIMS) and the cytotoxic activity of the compounds 1–4 was evaluated on HeLa cell line.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
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Suresh Kumar Mondal Susanta Kumar Manna Arabinda Mandal Shubhankar Samanta Jayanta K. Ray 《Tetrahedron letters》2014
A convenient and efficient procedure has been developed for the synthesis of a new ring system, pyrrolo[1,2-b]pyrazolone, via two-component coupling reaction followed by base mediated intramolecular cyclization. Single-pot synthesis replacing the two step process has also been successfully carried out. A series of polycyclic pyrrolo[1,2-b]pyrazolone derivatives have been obtained by employing the procedure along with some fused pyrrol-1-ylamine system. The products were formed very rapidly in catalyst free condition in a good yield (up to 75%) and also it had tolerance to a wide scope of substrates. 相似文献
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Somnath Roy Tarak Nath Mandal Anil Kumar Barik Samik Gupta Ray J. Butcher Munirathinam Nethaji Susanta Kumar Kar 《Polyhedron》2008
Two pyrimidine based NNS tridentate Schiff base ligands S-methyl-3-((2-S-methyl-6-methyl-4-pyrimidyl)methyl)dithiocarbazate [HL1] and S-benzyl-3-((2-S-methyl-6-methyl-4-pyrimidyl)methyl)dithiocarbazate [HL2] have been synthesised by 1:1 condensation of 2-S-methylmercapto-6-methylpyrimidine-4-carbaldehyde and S-methyl/S-benzyl dithiocarbazate. One Co(III) and one Mn(II) complex of HL1 and one Mn(II) complex of HL2 have been prepared and characterized by elemental analyses, molar conductivities, magnetic susceptibilities and spectroscopic studies. All the bis-chelate complexes have a distorted octahedral arrangement with an N4S2 chromophore around the central metal ion. Each ligand molecule binds the metal ion using pyrimidyl nitrogen, azomethine nitrogen and the thiolato sulfur atoms. In the free ligand moieties, the pyrimidine nitrogen atoms, azomethine nitrogen atoms and thione sulfur atoms are in EEE orientation to each other. During chelation, all the donor sites of the ligands are reoriented to ZEZ configuration in order to facilitate the chelation process. In all the complexes, the respective ligand molecule functions as the monoanionic tridentate one. All complexes were analyzed by single crystal X-ray diffraction and significant differences concerning the distortion from octahedral geometry of the coordination environment were observed. 相似文献
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The synthesis, molecular and supramolecular structure, spectroscopy and electrochemistry of a dialkoxo-bridged diuranyl(VI) compound [(UO2)2(L)2(dimethylformamide)2] (1) derived from the Schiff base ligand H2L, obtained on condensation of 3-methoxysalicylaldehyde with 2-aminoethanol, have been described. The compound has been characterized by IR, UV–Vis, NMR and mass spectra, as well as by single crystal X-ray structure determination. The title compound crystallizes in the monoclinic P21/n space group with the following unit cell parameters a = 10.5713(2) Å, b = 11.9895(2) Å, c = 12.9372(2) Å, β = 102.773(3)° and Z = 2. The structure of 1 reveals that it is a dialkoxo-bridged dinuclear compound of uranium(VI) containing two deprotonated ligands, [L]2−, two dimethylformamide (dmf) molecules and two UO22+ centers. The coordination geometry around the uranium(VI) center is distorted pentagonal bipyramidal; two uranyl oxygens occupy the axial positions, while the basal pentagonal plane is defined by a phenoxo oxygen, two bridging alkoxo oxygens, one imine nitrogen, and one dmf oxygen. Three C–H?O type hydrogen bonds involving one uranyl oxygen, two dmf hydrogens and the imine hydrogen link the dinuclear units into a two-dimensional network. The ESI-MS spectrum of 1 in dimethylsulfoxide exhibits two peaks at m/z = 464.17 and 927.26, which are assignable to [(UO2)2L2H]+ (60%) and [(UO2)2LH]+ (100%) cations, respectively. Cyclic voltammetric measurements of 1 reveal that the uranium(VI) center is reduced quasireversibly at E1/2 = −1112 mV with ΔEP = 97 mV. 相似文献
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