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151.
152.
Ridaphun Nongrum George Kupar Kharmawlong Jims World Star Rani Noimur Rahman Arup Dutta Rishanlang Nongkhlaw 《Journal of heterocyclic chemistry》2019,56(10):2873.-2883
The development of a metal‐free protocol for transformations in organic synthesis offers a significant potential environmental benefit. This article reports the exploration of meglumine, a nontoxic and biodegradable amino sugar, as an organocatalyst for the synthesis of biologically active 1H‐dibenzo[b,e][1,4]diazepin‐1‐ones, highly regioselective benzimidazole derivatives and derivatives of quinoxalines. Operational simplicity, mild reaction conditions, shorter reaction times, and use of green solvents are the highlights of this protocol. The advantage of ultrasonic irradiation has been significantly explored for the synthesis of the aforesaid compounds. Furthermore, the multifaceted use of o‐phenylenediamine has also been accentuated in the study. 相似文献
153.
Shubham Dutta Rajendra K. Mallick Rangu Prasad Vincent Gandon Akhila K. Sahoo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2311-2316
Ynamides are typically more reactive than simple alkynes and olefins. However, a serendipitous observation revealed a rare case where the reactivity of simple alkynes exceeds that of ynamides. This led to the development of a unique sulfur‐radical‐triggered cyclization of yne‐tethered ynamides, which involves attack of the alkyne by a thiyl radical followed by cyclization with the ynamide. A wide range of novel 4‐thioaryl pyrroles that could tolerate common functional moieties and N‐protecting groups were expediently constructed by this strategy. The current method contrasts with the typical cyclization of yne‐ynamides, which involves the attack of the alkyne moiety by the ynamide core. Control experiments and DFT calculations supported the participation of the sulfur radical in the reaction and the regioselective cyclization. The synthetic potential of the substituted pyrroles is also discussed. 相似文献
154.
We study the creation of solitons from particles, using the lambdaphi(4) model as a prototype. We consider the scattering of small, identical, wave pulses, which are equivalent to a sequence of particles, and find that kink-antikink pairs are created for a large region in parameter space. We also find that scattering at low velocities is favorable for creating solitons that have large energy compared to the mass of a particle. 相似文献
155.
Solvignon P Liyanage N Chen JP Choi S Aniol K Averett T Boeglin W Camsonne A Cates GD Chang CC Chudakov E Craver B Cusanno F Deur A Dutta D Ent R Feuerbach R Frullani S Gao H Garibaldi F Gilman R Glashausser C Gorbenko V Hansen O Higinbotham DW Ibrahim H Jiang X Jones M Kelleher A Kelly J Keppel C Kim W Korsch W Kramer K Kumbartzki G Lerose JJ Lindgren R Ma B Margaziotis DJ Markowitz P McCormick K Meziani ZE Michaels R Moffit B Monaghan P Munoz Camacho C Paschke K Reitz B Saha A Sheyor R 《Physical review letters》2008,101(18):182502
We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_{1} of the neutron and 3He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c);{2}. Global duality is observed for the spin-structure function g_{1} down to at least Q;{2}=1.8 (GeV/c);{2} in both targets. We have also formed the photon-nucleon asymmetry A1 in the resonance region for 3He and found no strong Q2 dependence above 2.2 (GeV/c);{2}. 相似文献
156.
H. Mkrtchyan P.E. Bosted G.S. Adams A. Ahmidouch T. Angelescu J. Arrington R. Asaturyan O.K. Baker N. Benmouna C. Bertoncini H.P. Blok W.U. Boeglin H. Breuer M.E. Christy S.H. Connell Y. Cui M.M. Dalton S. Danagoulian D. Day T. Dodario J.A. Dunne D. Dutta N. El Khayari R. Ent H.C. Fenker V.V. Frolov L. Gan D. Gaskell K. Hafidi W. Hinton R.J. Holt T. Horn G.M. Huber E. Hungerford X. Jiang M. Jones K. Joo N. Kalantarians J.J. Kelly C.E. Keppel V. Kubarovsky Y. Li Y. Liang S. Malace P. Markowitz E. McGrath P. McKee D.G. Meekins B. Moziak T. Navasardyan 《Physics letters. [Part B]》2008
157.
Manas Mahapatra Arnab Dutta Joy Sankar Deb Roy Ujjal Das Dr. Snehasis Banerjee Prof. Sanjit Dey Dr. Pijush Kanti Chattopadhyay Prof. Dilip K. Maiti Dr. Nayan Ranjan Singha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(2):502-516
To circumvent costly fluorescent labeling, five nonconventional, multifunctional, intrinsically fluorescent aliphatic terpolymers ( 1 – 5 ) have been synthesized by C−C/C−N-coupled, solution polymerization of two non-emissive monomers with protrusions of fluorophore monomers generated in situ. These scalable terpolymers were suitable for sensing and high-performance exclusion of CuII, logic function, and bioimaging. The structures of the terpolymers, in situ attachment of fluorescent monomers, aggregation-induced enhanced emission, bioimaging ability, and super adsorption were investigated by 1H and 13C NMR, EPR, FTIR, X-ray photoelectron, UV/Vis, and atomic absorption spectroscopy, thermogravimetric analysis, high-resolution transmission electron microscopy, dynamic light scattering, solid-state fluorescence, fluorescence imaging, and fluorescence lifetime measurements, as well as by isotherm, kinetics, and thermodynamic studies. The geometries and electronic structures of the fluorophores and the absorption and emission properties of the terpolymers were examined by DFT, time-dependent DFT, and natural transition orbital analyses. For 1 , 2 , and 5 , the limits of detection were determined to be 1.03×10−7, 1.65×10−7, and 1.77×10−7 m , respectively, and the maximum adsorption capacities are 1575.21, 1433.70, and 1472.21 mg g−1, respectively. 相似文献
158.
In this article, we have studied the bound anionic states of DNA and RNA nucleobases using the newly developed bt-PNO-EOM-CCSD method and extended basis sets. All of the five nucleobases have a single bound anionic state, which is dipole bound in nature. The electron affinity corresponding to the dipole-bound state is found to be extremely sensitive to the used basis set, and a proper agreement with the available experimental data requires a large basis set with a sufficient number of diffuse functions. Electron correlation plays a major role in stabilizing the bound anionic states of nucleobases. No valence-bound anionic states are observed for any of the nucleobases. 相似文献
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