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排序方式: 共有266条查询结果,搜索用时 31 毫秒
41.
42.
Vijay S. Parmar Dr. David P. Mills Prof. Richard E. P. Winpenny 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(28):7625-7645
Recent studies have shown that mononuclear lanthanide (Ln) complexes can be high-performing single-molecule magnets (SMMs). Recently, there has been an influx of mononuclear Ln alkoxide and aryloxide SMMs, which have provided the necessary geometrical control to improve SMM properties and to allow the intricate relaxation dynamics of Ln SMMs to be studied in detail. Here non-aqueous Ln alkoxide and aryloxide chemistry applied to the synthesis of low-coordinate mononuclear Ln SMMs are reviewed. The focus is on mononuclear DyIII alkoxide and aryloxide SMMs with coordination numbers up to eight, covering synthesis, solid-state structures and magnetic attributes. Brief overviews are also provided of mononuclear TbIII, HoIII, ErIII and YbIII alkoxide and aryloxide SMMs. 相似文献
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44.
Virinder S Parmar Kirpal S Bisht Amarjit Singh Amitabh Jha 《Journal of Chemical Sciences》1996,108(6):575-583
Enantioselection effected by commercially available hydrolytic enzymes reported in recent years from our own laboratory and
those published by other groups is described. The discussion is confined to enantioselection in symmetric diols, amino acids
and benzopyran derivatives only. The paper describes a variety of substrates accepted by these hydrolytic enzymes to produce
compounds in high enantiomeric excess which can be used as chiral building blocks for the synthesis of compounds of pharmaceutical
and synthetic interest. 相似文献
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47.
Two-dimensional electrophoresis of cereal prolamins: applications to biochemical and genetic analyses 总被引:1,自引:0,他引:1
Three complementary two-dimensional systems for the analysis of cereal prolamins are described. These are electrophoresis at pH 3.1 followed by electrophoresis at pH 9.2, isoelectric focusing (IEF) followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and SDS-PAGE under non-reducing conditions followed by SDS-PAGE with reduction. They together give information on the pIs, Mrs and charge properties of the individual prolamin components, and on their interactions to form oligomers stabilized by inter-chain disulphide bonds. The three systems are then compared for their effectiveness in analysing unreduced prolamin I fractions from wheat and rye, and the IEF/SDS-PAGE system for analysing reduced and pyridylethylated prolamin fractions from all the major cereals. Finally, applications of the systems in biochemical and genetic studies are discussed and illustrated with three examples: analysis of the structural relationships of the S-rich prolamins (B hordeins and gamma-type hordeins) of barley, determination of the interactions of wheat and rye prolamin subunits in a 2RS/2BL translocation line, and the mapping of genes for alpha-type prolamins in the wild grass Haynaldia villosa. 相似文献
48.
The kinetics of RuVI-catalysed oxidation of ethane-1,2-diol, propane-1,3-diol, butane-1,3-diol, butane-1,4-diol and 2-butoxyethanol by hexacyanoferrate(III) ion in an aqueous alkaline medium at constant ionic strength shows zeroth order dependence on hexacyanoferrate(III) and first order dependence on RuVI and substrate. The results suggest that a complex is formed, between RuVI and the diol, which slowly decomposes to a reduced form of ruthenium, which is reoxidized to RuVI in a fast step by alkaline hexacyanoferrate(III). A plausible reaction mechanism is proposed. 相似文献
49.
R. S. Misra C. Dwivedi S. S. Parmar S. P. Singh 《Journal of heterocyclic chemistry》1978,15(4):681-682
Six 1-(N-acetylpiperidino)-4-aryl semicarbazides were synthesized from ethyl-N-piperidino-aeetatc which on treatment with hydrazine hydrate was converted into N-piperidinoacethydrazide. The resulting hydrazide on treatment with the appropriate arylisoeyanales formed l -(N-acelyl-piperidino)-4-aryl semicarbazides. Amongst these piperidinosemicarbazides, three compound possessed low anticonvulsanl activity and provided 20-40% protection against pentylenetetrazol-induced convulsions in mice. All piperidino semicarbazides (0.1 mM) possessed antihemolytic activity (13-35%) and caused 40-72% inhibition of monoamine oxidase activity of rat brain homogenates at a final concentration of 0.3 mM. 相似文献
50.
Suman Mehrotra Jayanti P. Barthwal Bhagwan R. Pandey Krishna P. Bhargava Surendra S. Parmar 《Journal of heterocyclic chemistry》1980,17(6):1213-1214
Several 2-aryl substituted thiosemicarbazido-4-methyl-6-methoxyquinolines and 2-aryl substituted semi-carbazido 4-methyl-6-methoxyquinolines were synthesized and evaluated for their antimalarial activity in mice infected with Plasmodium berghei. Two of these substituted quinolines were found to exhibit 50% clearance in a dose of 500 mg./kg. administered intraperitoneally for 5 days. 相似文献