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81.
The intramolecular protective group (benzylidene acetal) assisted syn-1,3-diol synthesis has been efficiently utilized in a short synthesis of 6-epiprelactone-V starting from (S)-malic acid.  相似文献   
82.
A combination of "chiron" and "asymmetric" approaches is utilized to construct the southern (C 9-C 25) region of marine natural product spirastrellolide B. The key functionalities are derived from d-glucose and Sharpless asymmetric epoxidation and dihydroxylation.  相似文献   
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Sakram  B.  Ravi  D.  Ashok  K.  Rambabu  S.  Sonyanaik  B.  Kurumanna  A. 《Russian Journal of General Chemistry》2018,88(4):780-788
Russian Journal of General Chemistry - The Buchwald–Hartwig amination reaction between 2-chloro-3-aryl-1,8-naphthyridines and 2-(4-aminophenyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione in the...  相似文献   
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Summary The oxidation of selenium(IV) by permanganate has been studied kinetically in acid, neutral and alkaline media. The reaction exhibits unit-order dependence on selenium(IV) and permanganate in all the three media. Manganese(VI) retards the reaction in alkaline medium. The rate-limiting step is the same in all the three media, but the stoichiometry is different, being 2:1 in alkaline medium, 2:3 in neutral medium and 2:5 in acid medium. Evidence has been obtained for a one electron-transfer in the rate-determining step.  相似文献   
86.
A series of novel bivalent metal complexes M(L1)2 and M(L2)2 where M = Cu(II), Ni(II), Co(II) and L1 = 2-((benzo [d] thiazol-6-ylimino)methyl)-4-bromophenol [BTEMBP], L2 = 1-((benzo [d] thiazol-6-ylimino)methyl) naphthalen-2-ol [BTEMNAPP] were synthesized. All the compounds have been characterized by elemental analysis, SEM, Mass, 1H NMR, 13C NMR, UV–Vis, IR, ESR, spectral data and magnetic susceptibility measurements. Based on the analytical and spectral data four-coordinated square planar geometry is assigned to all the complexes. DNA binding properties of these complexes have been investigated by electronic absorption spectroscopy, fluorescence and viscosity measurements. It is observed that these binary complexes strongly bind to calf thymus DNA by an intercalation mode. DNA cleavage efficacy of these complexes was tested in presence of H2O2 and UV light by gel electrophoresis and found that all the complexes showed better nuclease activity. Finally the compounds were screened for antibacterial activity against few pathogens and found that the complexes have potent biocidal activity than their free ligands.  相似文献   
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New self-assembled material (Ru@SC) with ruthenium nanoparticles (Ru NPs) and 4-sulfocalix[4]arene (SC) is synthesized in water at room temperature. Ru@SC is characterized by thermal gravimetric analysis, FT-IR, powder x-ray diffraction, TEM and SEM analysis. The size of Ru nanoparticles in the self-assembly is approximately 5 nm. The self-assembled material Ru@SC shows an efficient catalytic reduction of toxic ‘brilliant yellow’ (BY) azo dye. The reduced amine products were successfully separated and confirmed by single-crystal XRD, NMR and UV-Vis spectroscopy. Ru@SC showed a better catalytic activity in comparison with commercial catalysts Ru/C (ruthenium on charcoal 5 %) and Pd/C (palladium on charcoal 5 and 10 %). The catalyst also showed a promising recyclability and heterogeneous nature as a catalyst for reduction of ‘BY’ azo dye.
Graphical abstract ?
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Ultrasonic sound velocities and densities of binary mixtures of 1-bromobutane with propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol, heptan-1-ol and octan-l-ol have been experimentally determined at 303·15 K. Isentropic compressibilities (K s) and deviations in isentropic compressibilities (ΔK S) have been calculated from the results. The values of ΔKS are almost positive over the entire range of composition in all six binary liquid mixtures. The experimental results are explained in terms of depolymerisation of hydrogen-bonded alcohol aggregates, decrease in dipolar association and weak hydrogen-bonding interaction of the type Br---H-O between unlike molecules.  相似文献   
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