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81.
Pooja Rani Heena Niharika Pundir Gauri Dr. Ahmad Husain Dr. K. K. Bhasin Dr. Girijesh Kumar 《欧洲无机化学杂志》2023,26(8):e202200654
A doubly interpenetrated Cu(II)-organic framework with formula [{Cu2( L )2(4,4′-bpdc)2(H2O)2} ⋅ 8H2O ⋅ CH3OH]α ( 1 ) (where, L =N2, N6-di(pyridin-4-yl)naphthalene-2,6-dicarboxamide and 4,4′-bpdc=[1,1′-biphenyl]-4,4′-dicarboxylate ion) has been synthesized and characterized with the help of several spectroscopic and analytical techniques including single crystal X-ray analysis. A single crystal X-ray analysis reveals that 1 exhibit interpenetrated two-dimensional sheet-like structure containing elongated channels of cross-section 11.09×31.22 Å2 along the a-axis. Finally, 1 has been exploited as a heterogeneous catalyst for the ipso-hydroxylation of arylboronic acids yielding up to 99 % of the respective phenolic product. Importantly, the catalyst can be reused for five successive cycles without having a significant loss in its catalytic efficiency. 相似文献
82.
Megan M. Wancura Quinn Anex‐Ries Anna L. Carroll Ana Paola Garcia Pooja Hindocha Maren E. Buck 《Journal of polymer science. Part A, Polymer chemistry》2017,55(19):3185-3194
The work reported here demonstrates an approach to the fabrication of chemically reactive and topographically patterned hydrogels using the azlactone‐functionalized polymer poly(2‐vinyl‐4,4'‐dimethylazlactone) (PVDMA) and the hydrophilic diamine Jeffamine®. Gels were initially assembled in DMSO but can be subsequently transferred into aqueous media to form hydrogels. Spectroscopic characterization of assembled gels demonstrated that variation in the stoichiometric ratio of azlactones to amines during gel synthesis permits control over the extent of crosslinking in the gels. Residual azlactones not consumed during crosslinking can be exploited to further functionalize these gels with hydrophobic, hydrophilic, and macromolecular amines that influence the physicochemical properties of these materials in aqueous solvents. The surface and bulk of these gels can be differentially functionalized (i.e., different functional groups on the gel surface relative to the bulk) by taking advantage of different rates of diffusion of macromolecular amines versus small molecule amines into assembled gels. Finally, these azlactone‐functionalized gels can be topographically patterned with microwell arrays using a replica molding technique and chemically modified postfabrication with amine nucleophiles. This reactive approach to the fabrication of topographically patterned and chemically functionalized hydrogels offers a straightforward method for the rapid synthesis of micropatterned scaffolds of interest in a broad range of applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3185–3194 相似文献
83.
Molecular Diversity - A regioselective three-component reaction of α,β-unsaturated aldehydes, cyclic 1,3-dicarbonyls and 6-aminouracils in the presence of FeCl3·6H2O as catalyst... 相似文献
84.
Pooja R. Kumar G. Kumar R. Kumar Anil Kumar 《International journal of quantum chemistry》2016,116(19):1413-1418
In this work, the position and momentum space information densities of the Eckart potential are graphically demonstrated and their properties are studied. The position space information densities have quite an asymmetric shape depending on the values of quantum numbers. The information entropy is obtained and Bialynicki‐Birula and Mycielski inequality is numerically saturated for some parameters of the potential. It is shown that the inequality is saturated with increasing potential depth. 相似文献
85.
86.
The solution and solid state conformations of a designed β-hairpin containing functionalizable α,β-unsaturated γ-amino acids at the antiparallel β-strands and a single step transformation to its saturated γ-peptide analogue are studied. 相似文献
87.
Arora P Venkataswamy MM Baena A Bricard G Li Q Veerapen N Ndonye R Park JJ Lee JH Seo KC Howell AR Chang YT Illarionov PA Besra GS Chung SK Porcelli SA 《Journal of the American Chemical Society》2011,133(14):5198-5201
Structural variants of α-galactosylceramide (αGC) that activate invariant natural killer T cells (iNKT cells) are being developed as potential immunomodulatory agents for a variety of applications. Identification of specific forms of these glycolipids that bias responses to favor production of proinflammatory vs anti-inflammatory cytokines is central to current efforts, but this goal has been hampered by the lack of in vitro screening assays that reliably predict the in vivo biological activity of these compounds. Here we describe a fluorescence-based assay to identify functionally distinct αGC analogues. Our assay is based on recent findings showing that presentation of glycolipid antigens by CD1d molecules localized to plasma membrane detergent-resistant microdomains (lipid rafts) is correlated with induction of interferon-γ secretion and Th1-biased cytokine responses. Using an assay that measures lipid raft residency of CD1d molecules loaded with αGC, we screened a library of ~200 synthetic αGC analogues and identified 19 agonists with potential Th1-biasing activity. Analysis of a subset of these novel candidate Th1 type agonists in vivo in mice confirmed their ability to induce systemic cytokine responses consistent with a Th1 type bias. These results demonstrate the predictive value of this novel in vitro assay for assessing the in vivo functionality of glycolipid agonists and provide the basis for a relatively simple high-throughput assay for identification and functional classification of iNKT cell activating glycolipids. 相似文献
88.
In situ generated aza-diene, from N-[methyl-N-(trimethylsilyl)methyl]aniline in the presence of a catalytic amount of molecular iodine undergoes smooth [4+2] cycloaddition with electron-rich enol ethers, such as 3,4-dihydro-2H-pyran and 2,3-dihydrofuran under mild and neutral conditions to afford the corresponding hexahydropyrano- and furo[3,2-c]quinoline derivatives, respectively, in good yields with cis-selectivity. 相似文献
89.
Sunil Singh Chouhan Pooja Soni Gitanjali Pagare S.P. Sanyal M. Rajagopalan 《Physica B: Condensed Matter》2011,406(3):339-344
A theoretical study of structural, electronic, elastic, thermal and mechanical properties of nonmagnetic intermetallics YM (M=Cu, Zn and Ag), which crystallize in CsCl-type structure, is performed using first principles density functional theory based on full potential linearized augmented plane wave (FP-LAPW) method. The calculations are carried out within the generalized gradient approximation (GGA) for the exchange correlation potential. The calculated ground state properties such as lattice constants, bulk modulus and elastic constants agree well with the experiment. From energy dispersion curves, it is found that these compounds are metallic in nature. The ductility of these intermetallics is determined by calculating the bulk to shear ratio B/GH. The calculated results indicate that YAg is the most ductile amongst the present YM compounds. The results obtained are compared with the available experimental and theoretical results. The mechanical and thermal properties are predicted from the calculated values of elastic constants. 相似文献
90.
Resonant soft X-ray reflectivity measurements at and near the L3 absorption edge of sulphur have been performed on mechanically polished zinc sulphide using Indus-1 synchrotron source. A sulphur rich surface (∼15 nm thick) consisting of two layers with gradient electron density distribution was uniquely determined. As compared to bulk ZnS, the top layer has ∼30-50% less electron density whereas, the intermediate layer has ∼10-18% less electron density. Conventional hard X-ray reflectivity measurement at Cu Kα wavelength also indicates low electron density (sulphur rich) surface of ZnS but the technique was found insensitive for unique determination of electron density distribution. Optical constants of ZnS in the soft X-ray region (100-250 eV) have been reported for the first time and were in good agreement with the theoretically reported values. 相似文献