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41.
A concise total synthesis of 11-O-methyldebenzoyltashironin is reported in which oxidative dearomatization-IMDA-RCM triad constitutes the key ring forming steps, while an unorthodox DIBAL-H mediated stereo- and regioselective reductive epoxide openings and implementation of the vinyl bromide-carbonyl equivalency concept were pivotal to the success of this endeavor. 相似文献
42.
Kalyanmoy Jana Somnath Das Tithi Maity Maidul Hossain Subhas Chandra Debnath 《Journal of Coordination Chemistry》2018,71(10):1497-1509
A new Co(II) complex of general formula [Co(L)2] has been synthesized from a NNO tridentate Schiff base ligand, 2-[(piperidin-2-ylmethylimino)-methyl]-phenol (L). The title complex is characterized by elemental, spectroscopic, antibacterial, and single crystal X-ray structural studies. X-Ray crystallography reveals that the complex shows a distorted octahedral geometry around the Co(II) ion. The complex was tested against several bacteria and shows good antibacterial activities against almost all of the bacteria. The interactions of the title complex with calf thymus deoxyribonucleic acid (CT-DNA) have been investigated by electronic absorption and fluorescence spectroscopy, showing that the complex interacts with CT-DNA via partial intercalation. Thermogravimetric analysis (TGA) of the complex has also been reported and the result shows that the complex is thermally stable up to 134 °C. 相似文献
43.
Ambarish Ray Dipankar Maity Anup Pramanik Kalyan K. Das Mahasweta Nandi Asim Bhaumik M. Nethaji Swastik Mondal Monika Mukherjee Mahammad Ali 《Polyhedron》2009,28(17):3659-3666
Two new copper(II) complexes, [Cu2(L1)2](ClO4)2 (1) and [Cu(L2)(ClO4)] (2), of the highly unsymmetrical tetradentate (N3O) Schiff base ligands HL1 and HL2 (where HL1 = N-(2-hydroxyacetophenone)-bis-3-aminopropylamine and HL2 = N-(salicyldehydine)-bis-3-aminopropylamine) have been synthesised using a template method. Their single crystal X-ray structures show that in complex 1 two independent copper(II) centers are doubly bridged through phenoxo-O atoms (O1A and O1B) of the two ligands and each copper atom is five-coordinated with a distorted square pyramidal geometry. The asymmetric unit of complex 2 consists of two crystallographically independent N-(salicylidene)-bis(aminopropyl)amine-copper(II) molecules, A and B, with similar square pyramidal geometries. Cryomagnetic susceptibility measurements (5–300 K) on complex 1 reveal a distinct antiferromagnetic interaction with J = ?23.6 cm?1, which is substantiated by a DFT calculation (J = ?27.6 cm?1) using the B3LYP functional. Complex 1, immobilized over highly ordered hexagonal mesoporous silica, shows moderate catalytic activity for the epoxidation of cyclohexene and styrene in the presence of TBHP as an oxidant. 相似文献
44.
Subhendu Naskar Priyankar Paira Rupankar Paira Shyamal Mondal Arindam Maity Abhijit Hazra Krishnendu B. Sahu Pritam Saha Sukdeb Banerjee Peter Luger Manuela Webe Nirup B. Mondal 《Tetrahedron》2010,66(27-28):5196-5203
An environmentally benign protocol has been described for the synthesis of novel 2-(1′,3′-dihydro-1H-[2,3′]biindolyl-2′-ylidene)-indan-1,3-diones/bis-indolylindane-1,3-diones from ninhydrin and 3-substituted/unsubstituted indoles. It uses montmorillonite K-10 as catalyst in a solvent-free condition under microwave irradiation. The method was also used for the synthesis of novel bisindolylindeno[1,2-b]quinoxaline derivatives. 相似文献
45.
Arijit Das Eric Soehnlen Stephan Woods Ravi Hegde Amanda Henry Arne Gericke Soumitra Basu 《Journal of nanoparticle research》2011,13(12):6283-6290
We report a novel gold nanobioconjugate system that achieves targeted delivery of the small molecule drug doxorubicin to endothelial
cells using anti-VEGFR-2 antibody conjugated gold nanoparticles (GNPs). The reported nanobioconjugate system combines the
inherent ability of GNPs to undergo high levels of derivatization with the precision of antibody recognition of a cell surface
antigen. Transmission electron microscopy (TEM) and surface-enhanced Raman spectroscopy (SERS) confirmed intracellular presence
of the GNPs. Using a VEGFR-2 expressing cell line and a cell line that is negative for the receptor, in combination with competition
assay we established the cell specific targeted delivery of the nanobioconjugate. The nanobioconjugate system described here
may have potential drug delivery applications for antiangiogenic cancer therapy. 相似文献
46.
We propose a gravity dual for the holographic superconductor with multi-band carriers. Moreover, the currents of these carriers are unified under a global flavored SO(3) symmetry, which is dual to the bulk SO(3) gauge symmetry. We study the phase diagram of our model, and find it qualitatively agrees with the one for the realistic 2-band superconductor, such as MgB2. We also identify the bulk field dual to the electromagnetic UEM(1) current, which should be invariant under the global flavored SO(3) rotation. We then evaluate the corresponding holographic conductivity and find the expected mean field like behaviors. 相似文献
47.
48.
Estimation of distribution coefficient of polonium in geological matrices around uranium mining site 总被引:1,自引:0,他引:1
Sukanta Maity S. Mishra S. Bhalke G. G. Pandit V. D. Puranik H. S. Kushwaha 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(1):75-79
In case of ground (groundwater) contamination or contaminants release from the disposal modules (facilities) to the geo-environment,
the fate of contaminant transport is mainly governed by the parameter called distribution (partition) coefficient, K
d. It is a measure of sorption of contaminants to soils. For that the sorption of polonium in soil were carried out using laboratory
batch method in different soil samples collected from different places around Turamdih uranium mining site. The kinetics of
polonium sorption were also carried out at different time intervals which clearly indicates that sorption equilibrium for
polonium achieved at around 72 h. The K
d for polonium varies from 1,443 to 7,501.3 L/kg in soil samples. Chemical characterization of soil and ground water samples
were carried out to know the effect of various chemical parameters with distribution coefficient of polonium. 相似文献
49.
We consider the problem of testing for a constant nonparametric effect in a general semiparametric regression model when there is a potential for interaction between the parametrically and nonparametrically modeled variables. The work was originally motivated by a unique testing problem in genetic epidemiology (Chatterjee et al., 2006) that involved a typical generalized linear model but with an additional term reminiscent of the Tukey 1-degree-of-freedom formulation, and their interest was in testing for main effects of the genetic variables, while gaining statistical power by allowing for a possible interaction between genes and the environment. Later work (Maity et al., 2009) involved the possibility of modeling the environmental variable nonparametrically, but they focused on whether there was a parametric main effect for the genetic variables. In this paper, we consider the complementary problem, where the interest is in testing for the main effect of the nonparametrically modeled environmental variable. We derive a generalized likelihood ratio test for this hypothesis, show how to implement it, and provide evidence that our method can improve statistical power when compared to standard partially linear models with main effects only. We use the method for the primary purpose of analyzing data from a case-control study of colorectal adenoma. 相似文献
50.
Maity P Tsunoyama H Yamauchi M Xie S Tsukuda T 《Journal of the American Chemical Society》2011,133(50):20123-20125
A new class of monolayer-protected Au clusters with Au-C covalent bonds (organogold clusters) was synthesized by ligating phenylacetylene (PhC≡CH) to PVP-stabilized Au clusters. Matrix-assisted laser desorption ionization mass spectrometry revealed for the first time a series of stable compositions of the organogold (Au:C(2)Ph) clusters. 相似文献