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101.
Very productive Grignard-type addition of sugar alkynes to imines via C–H activation using Cu–Ru catalyst was achieved under microwave conditions. The resulting glyco-conjugates are attractive for future evaluation as potential drug-like molecules. 相似文献
102.
Santosh SinghPankaj Singh Vijai K. Rai Ritu KapoorLal Dhar S. Yadav 《Tetrahedron letters》2011,52(1):125-128
The first example of N-heterocyclic carbene (NHC)-promoted intermolecular acylation of α-haloketones with aldehydes and α,β-unsaturated aldehydes (enals) is reported. The protocol involves carbonyl umpolung reactivity of aldehydes and enals in which the carbonyl carbon attacks nucleophilically on electrophilic terminal of α-haloketones to afford 1,3-diketones and α,β-unsaturated 1,3-diketones, respectively. Short reaction time, ambient temperature, operational simplicity, and high yields are the salient features of the present procedure. 相似文献
103.
Gita Seth Vijaya Kabra Jasvinder Kaur Ritu Mathur Priti Kaushik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1001-1010
New tetracoordinated complexes of Zn (II) have been synthesized by the reaction between zinc chloride and 3-methyl-2-benzothiazolylidenamido-thiophosphoryl dichloride (L1), (3-methyl-2-benzothiazolylidenamido)-bis-(diethylamido)thiophosphate (L2), 3-benzyl-2-benzothiazolylidenamido thiophosphoryl dichloride (L3), and (3-benzyl-2-benzothiazolylidenamido)-bis-(diethyl-amido) thiophosphate (L4) in a 1:1 ratio. The complexes have been isolated and characterized by elemental analysis, electrical conductivity, and mass and IR spectral studies. The stability constants of these complexes also have been determined in aqueous solution by spectrophotometric methods. 相似文献
104.
105.
Pandya P Gupta SP Pandav K Barthwal R Jayaram B Kumar S 《Natural product communications》2012,7(3):305-309
Fluorescence studies on the indole alkaloids vinblastine sulfate, vincristine sulfate, vincamine and catharanthine have demonstrated the DNA binding ability of these molecules. The binding mode of these molecules in the minor groove of DNA is non-specific. A new parameter of the purine-pyrimidine base sequence specificty was observed in order to define the non-specific DNA binding of ligands. Catharanthine had shown 'same' pattern of 'Pu-Py' specificity while evaluating its DNA binding profile. The proton resonances of a DNA decamer duplex were assigned. The models of the drug:DNA complexes were analyzed for DNA binding features. The effect of temperature on the DNA binding was also evaluated. 相似文献
106.
Chiral conducting polymers prepared by electropolymerising PEDOT in the presence of chiral anions such as hyaluronic acid and anionic collagen or in a chiral nematic phase (hydroxypropyl cellulose, HPC) show excellent chiral acid recognition. This paper demonstrates the enantioselective recognition and transfer of protonated mandelic acid and protons using chiral PEDOTs. Discrimination between (R)-(-)- and (S)-(+)-mandelic acid was observed using cyclic voltammetry and square-wave voltammetry. 相似文献
107.
Crystallized 4,7‐diphyenyl‐1,10‐phenanthroline (BPhen) films deposited by convenient vacuum thermal evaporation technique have been found to be an efficient means to extract the substrate wave guided light in organic light emitting diodes (OLEDs). The optimized BPhen film working as organic scattering layer was successfully used with OLEDs for light outcoupling efficiency improvement. Enhancement of 26%, 15% and 6% in efficiency of the blue, green and red OLEDs were obtained, respectively. The achievement was found to be advantageous in terms of simplicity of fabrication method and feasibility for large area OLED applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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109.
This paper presents an interactive fuzzy goal programming (FGP) approach for bilevel programming problems with the characteristics of dynamic programming (DP). 相似文献
110.
Ritu Bala Raj Pal Sharma Paloth Venugopalan William T.A. Harrison 《Journal of Molecular Structure》2007,830(1-3):8-13
In an effort to utilize the [Co(NH3)6]3+ cation as a new anion receptor (binding agent) for dihydroxy dicarboxylate anion i.e., tartrate, orange single crystals of hexaamminecobalt(III) chloride (R,R)-tartrate monohydrate, [Co(NH3)6]Cl(C4H4O6)·H2O, were obtained by reacting hexaamminecobalt(III) chloride with potassium–sodium tartrate tetrahydrate in a 1:1 molar ratio in hot water. The single crystal X-ray structure determination of [Co(NH3)6]Cl(C4H4O6)·H2O revealed that a distinctive network of hydrogen bonding interactions (N–HO, N–HCl−, O–HO) stabilize the crystal lattice. This is the first complex salt of hexaamminecobalt(III) with dihydroxy dicarboxylate anion i.e., tartrate. 相似文献