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991.
M. A. Bruce D. R. St. Laurent G. S. Poindexter I. Monkovic S. Huang N. Balasubramanian 《合成通讯》2013,43(17):2673-2684
The resolution of N-t-Boc-piperazine carboxamide 5 proceeded smoothly in the presence of leucine aminopeptidase to produce acid (S)-1 and amide (R)-5 with good optical purity. Sequential alkylation and functional group manipulation of carboxamide (S)-5 provided the known nucleoside transport blocker draflazine (-) 2. 相似文献
992.
Bruce C. Gilbert Chris I. Lindsay P. Terry McGrail Andrew F. Parsons David T. E. Whittaker 《合成通讯》2013,43(15):2711-2718
Wurtz-type radical coupling of a variety of allylic and benzylic bromides was observed on irradiation with dimanganese decacarbonyl in excellent yield (77-99%). Efficient cross-coupling of two different bromides was also readily achieved. 相似文献
993.
994.
André C. Silva Alan Arroyo R. Bruce Richter Orlando Lee 《Discrete Mathematics》2019,342(11):3201-3207
The crossing number of a graph is the least number of crossings over all possible drawings of . We present a structural characterization of graphs with crossing number one. 相似文献
995.
John Tyman Shoreh Ghorbanian M. Muir Vasiliki Tychopoulous Ian Bruce Ian Fisher 《合成通讯》2013,43(1-2):179-188
The nucleophilic displacement reactions of 2- and 4- halogenonaphthalic-1,8, anhydrides and the N-imides, of 4,7- dichloroquinolines, the alkylation of lithio alkynes, the methylation of ethyl or methyl diacetylacetate and a variety of related reactions are greatly facilitated in N-methylpyrrolidinone as aprotic solvent. 相似文献
996.
997.
C. Dennis Hall Bruce R. Tweedy Nicholas Lowther 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):341-358
Abstract The kinetics and mechanism of the reaction of tricoordinate phosphorus compounds, ArnP(OCH2CF3)3-n with arylsulfenate esters, ArSOCH2CF3, are reported. Product analysis, kinetic order, activation parameters, Hammett data and solvent effects are the criteria used to elucidate the two step mechanism involving arylthiophosphoranes as intermediates. 相似文献
998.
Dr. Patrick L. Higgs Jordan L. Appleton Prof. Dr. W. Bruce Turnbull Dr. David A. Fulton 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17647-17654
There is growing interest in developing methods to ‘wrap’ nano- and micron-sized biological objects within films that may offer protection, enhance their stability or improve performance. We describe the successful ‘wrapping’ of lectin-decorated microspheres, which serve as appealing model micron-sized objects, within cross-linked polymer film. This approach utilizes polymer chains able to undergo a structural metamorphosis, from being intramolecularly cross-linked to intermolecularly cross-linked, a process that is triggered by polymer concentration upon the particle surface. Experiments demonstrate that both complementary molecular recognition and the dynamic covalent nature of the crosslinker are required for successful ‘wrapping’ to occur. This work is significant as it suggests that nano- and micron-sized biological objects such as virus-like particles, bacteria or mammalian cells—all of which may benefit from additional environmental protection or stabilization in emerging applications—may also be ‘wrapped’ by this approach. 相似文献
999.
1000.